JP2973033B2 - Synthetic lubricant - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a synthetic lubricating oil based on a cyclic ketal or a cyclic acetal compound having a specific structure as a base oil.
Further, the present invention relates to a refrigerator working fluid composition using the synthetic lubricating oil.

Further, the present invention relates to cyclic oils useful as polar oils, organic solvents, lubricants, synthetic lubricating oils, refrigerating machine oils, etc., and intermediates for producing surfactants, organic solvents, polar oils, synthetic lubricating oils, refrigerating machine oils, etc. The present invention relates to an acetal and a method for producing the acetal.

2. Description of the Related Art In recent years, the demand for lubricating oil has become more severe with the demand for longer oil refining periods and energy savings, as well as higher performance and smaller size of mechanical devices, and especially thermal stability. In addition, there is a strong demand for lubricating oils having excellent oxidation stability. Moreover, global warming due to the destruction and carbon dioxide, methane ozone layer by CFCs, deforestation sulfur dioxide and NO _x in exhaust gas, contamination of soil and lake due to leakage of chemicals, closes the environmental pollution It is being improved, and lubricating oil is also required to respond.

Ethers such as polyalkylene glycols and esters such as aliphatic diesters and hindered esters have been developed to meet the demand for improved thermal and oxidative stability. Engine oils, hydraulic oils, grease base oils, gear oils, rolling Used for oil, precision machine oil, etc.

However, ethers such as polyalkylene glycols have disadvantages such as high hygroscopicity and insolubility of conventionally used additives because they have too high a polarity compared to conventionally used mineral oils. As an ether having not much higher polarity than this polyalkylene glycol, there is an ether synthesized from an alkyl halide and a polyol described in Japanese Patent Publication No. 1-29240, but a small amount of halogen remains in the generated ether, There is a possibility that thermal stability and thermalization stability are deteriorated.

Ester also has the advantage of producing a carboxylic acid by hydrolysis to corrode the metal, and has the advantage of lowering the coefficient of friction due to its excellent adsorptivity to metal. And the like, which has the disadvantage of inhibiting the effects of

Therefore, there is a demand for a synthetic lubricating oil which is not so high in polarity, has excellent thermal stability and oxidative stability, does not generate carboxylic acid due to hydrolysis or the like, and has low hygroscopicity.

Meanwhile, the use of dichlorodifluoromethane (CFC12), which is used in refrigerators and car coolers to protect the ozone layer from the perspective of the global environment, has been regulated, and it has been decided that use will be banned at the end of 1995. In addition, the use of chlorodifluoromethane (HCFC22), which is used in room air conditioners, is being regulated. Therefore, this CFC12 and H
As an alternative to CFC22, hydrofluorocarbons that do not destroy the ozone layer, such as 1,1,1,2-tetrafluoroethane (HFC134a) and difluoromethane (HFC32)
And pentafluoroethane (HFC125) have been developed.

However, hydrofluorocarbons are CFC12 and HCFC22
Because the polarity is higher than that, if a lubricating oil such as naphthenic mineral oil or poly-α-olefin, alkylbenzene, etc., which has been generally used as a refrigerating machine oil, the compatibility between these lubricating oils and hydrofluorocarbons is poor,
Causes two-phase separation at low temperatures. When two layers are separated,
Oil return deteriorates, a thick oil film adheres near a condenser or evaporator as a heat exchanger, hinders heat transfer, and causes important defects such as poor lubrication and foaming at startup. Therefore, the conventional refrigerating machine oil cannot be used as a refrigerating machine oil under these new refrigerant atmospheres. Therefore, a lubricating oil having good compatibility with hydrofluorocarbon is required.

In terms of lubricity, in CFC12 and HCFC22,
It partially decomposes to generate hydrogen chloride, which has the effect of reacting with the friction surface to form a chloride film and improving lubricity. However, since such effects cannot be expected for hydrofluorocarbons containing no chlorine atom, lubricating oils that are more excellent in lubricity than conventional oils are required for refrigerating machine oils used with hydrofluorocarbons.

Further, the refrigerating machine oil used together with the hydrofluorocarbon needs to have good thermal stability in the presence of the hydrofluorocarbon.

In addition, since compression-type refrigerators such as electric refrigerators and room air conditioners contain organic materials used for motors such as insulating materials and enameled wires, a working fluid composed of hydrofluorocarbon and refrigerator oil is not available. It is necessary that these organic materials have no adverse effect and that the electrical insulation be good.

Examples of the refrigerating machine oil that can be used together with a hydrofluorocarbon, for example, 1,1,1,2-tetrafluoroethane (HFC134a) include U.S. Pat. (EP 377122) and JP-A-2-182780 (WO
No. 90/05172) discloses a polyalkylene glycol compound.

Since the polyalkylene glycol compound has a higher polarity than the naphthenic mineral oil, its compatibility with HFC134a at low temperatures is certainly good. However, U.S. Pat.
As described in the specification of Patent No. 6, polyalkylene glycol-based compounds have a problem that when the temperature rises, two-layer separation occurs. The polyalkylene glycol-based compound also has some other problems. One is that the electrical insulation is poor. This is a very big problem and cannot be used for refrigerators for electric refrigerators and air conditioners in which the motor is built into the compressor. These compounds have been suggested for use in car air conditioner applications without such concerns.
Another problem is high hygroscopicity. Due to the moisture in the polyalkylene glycol-based compound, HFC134a
Thermal stability in the presence of
The T film and the like are hydrolyzed. By reducing the number of ether bonds per unit weight, the electrical insulation can be improved and the hygroscopicity can be reduced, but the compatibility with the hydrofluorocarbon deteriorates. As described above, ether compounds such as polyalkylene glycol cannot achieve both compatibility with hydrofluorocarbons, electrical insulation properties, and hygroscopic properties.

Ester-based compounds and carbonate-based compounds have been developed in order to improve the problems of the polyalkylene glycol-based compounds such as electric insulation and hygroscopicity. For example, refrigeration oils that can be used with 1,1,1,2-tetrafluoroethane (HFC134a) include U.S. Pat. No. 4,851,144.
JP-A-2-276894 and JP-A-2-1586
No. 93 discloses a mixed oil of a polyalkylene glycol compound and an ester oil.
/ 12849), JP-A-3-128991, JP-A-3-1289
No. 92, JP-A-3-88892, JP-A-3-179909
Discloses an ester oil. In addition, Japanese Unexamined Patent Publication
JP-A-132178, JP-A-3-149295 and EP-A-421,298 disclose carbonate oils.

Ester-based compounds and carbonate-based compounds have excellent compatibility with hydrofluorocarbons and also have excellent thermal stability in the presence of hydrofluorocarbons. Compared to polyalkylene glycol-based compounds, they have extremely excellent electrical insulation properties, and have considerably low hygroscopicity. However, compared to the conventional working fluid CFC12-mineral oil system, hydrofluorocarbon-ester oil system and hydrofluorocarbon-carbonate oil system have CFC,
Both oils are highly polar and tend to contain water. Therefore, there is a problem that the ester is hydrolyzed to generate a carboxylic acid, and the generated carboxylic acid corrodes the metal and causes abrasion. In addition, there is a problem that the carbonate oil undergoes hydrolysis, generates non-condensable carbon dioxide, and lowers the refrigerating capacity.

In particular, in the case of a room air conditioner, since the on-site charging of the refrigerant is performed exclusively, it is almost impossible to prevent the incorporation of moisture different from the case of the refrigerator in which the industrial filling is performed. Then, the reliability of the room air conditioner is worried.

WO93 / 24435 discloses a polyvinyl ether compound as a polyether compound in which the problem of the electrical insulation of polyalkylene glycol is improved. This polyvinyl ether-based compound is obtained by polymerizing a vinyl ether-based monomer and hydrogenating it. It is disclosed that this compound has good compatibility with hydrofluorocarbon and good electric insulation. . However, polyvinyl ether compounds are synthesized by a polymerization method, and the product has a variation in molecular weight distribution. May worsen. Further, the post-treatment method is complicated, or an unstable vinyl ether-based monomer is used as a raw material, and it cannot be said that a good yield is always obtained. In particular, those having a low polymerization degree (near the polymerization degree of 6) have a disadvantage that the yield is low. Further, depending on the structure, it is difficult to obtain a raw material of a vinyl ether-based monomer, and it is expensive.

On the other hand, examples of using a cyclic ketal or a cyclic acetal as a working fluid for a refrigerator are disclosed in JP-A-4-320498 and JP-A-6-320498.
No. 57243. The former is a ketal or an acetal obtained from a monohydric alcohol or a dihydric alcohol and a ketone or an aldehyde, and is described as being used by being blended with an ester or a polyalkylene glycol-based synthetic lubricating oil. And glycerin, trimethylolethane, trimethylolpropane, pentaerythritol esters and carbonate derivatives containing a ketal or acetal group. The former acetals and ketals have the drawback that they have low molecular weight, low boiling points and low flash points, and the latter acetals and ketals have the drawback that they are expensive because they undergo two or more reaction steps in production. Also, some have the disadvantage that they are difficult to obtain with high purity. Further, the latter specifically disclosed as an acetal and a ketal have a problem that two or more ether bonds are contained in a molecule and the electric insulation property is not sufficiently improved.

As described above, the hydrofluorocarbon-polyalkylene glycols developed so far have a problem of hygroscopicity and electric insulation, and the hydrofluorocarbon-esters and the hydrofluorocarbon-carbonate have a problem of hydrolysis resistance. The system also contains water more easily than the conventional CFC12-mineral oil system, causing a decrease in thermal stability, deterioration of organic materials, corrosion and wear of metals, etc., and is not satisfactory as a working fluid for a refrigerator. Further, the polyvinyl ether-based compound has a molecular weight distribution, and therefore contains a part of a high molecular compound, which has a disadvantage of lowering the compatibility, has a disadvantage that the kind of raw material is limited, and it becomes expensive. Further, ketals and acetals which have been reported so far have the disadvantages of low molecular weight and high price.

By the way, heretofore, cyclic acetal has often been used as a protecting group in the field of synthesizing sugars and polyols, mainly using acetone as a ketone. Recently, 1,3-- synthesized from formaldehyde and ethylene glycol
Dioxolan is marketed as an organic solvent.

On the other hand, as a cyclic acetal synthesized from sorbitol and benzaldehyde, dibenzylidene sorbitol is known as a gelling agent, and a cyclic acetal synthesized from unsaturated aldehyde and sorbitol is used as a polymer raw material.

Also, sorbitol and acetone, formaldehyde,
Cyclic acetals synthesized from acetaldehyde or butyraldehyde are known, but no linear or branched one having a longer chain length is known. Further, a cyclic acetal synthesized from sorbitol and isobutyraldehyde is not known.

Examples of the use of cyclic acetals include the above-mentioned solvents such as organic solvents, inks, and paints, additives or gelling agents, polymer raw materials, and absorbents for absorption refrigerators (Japanese Patent Application Laid-Open No. 59-25892). Gazettes) and dehydrating agents for refrigeration oils (JP-A-4-320498, JP-A-6-57243).

To date, cyclic ketals with acetone have been synthesized to protect compounds such as sorbitol and mannitol, which are hexahydric alcohols, or to determine the structure, which have a high melting point, polar oils, It has been difficult to use it for applications requiring liquid properties near room temperature, such as synthetic lubricating oils and refrigerator oils. Further, those having an unsaturated alkyl chain have a feature that the melting point is lowered, but they have a disadvantage that they lack stability. Further, those having an aromatic ring such as a phenyl group are characterized by gelling, and are not suitable for applications such as polar oils, synthetic lubricating oils and refrigerating machine oils. On the other hand, cyclic acetals using an alcohol having a low valency, such as ethylene glycol, have a low viscosity and are not suitable for applications such as synthetic lubricating oils and refrigerating machine oils.

DISCLOSURE OF THE INVENTION Accordingly, an object of the present invention is to provide a synthetic lubricating oil which is excellent in heat stability, oxidation stability, does not generate carboxylic acid due to hydrolysis and the like, has low hygroscopicity, and is inexpensive. Another object of the present invention is to provide an inexpensive composition for a working fluid of a refrigerator, which is excellent in performance such as compatibility with a hydrofluorocarbon, electric insulation, hygroscopicity and the like, does not generate carboxylic acid due to hydrolysis or the like, and is inexpensive.

Another object of the present invention is to provide a novel cyclic acetal which is particularly suitable for applications such as synthetic lubricating oil and refrigerator oil. Still another object of the present invention is to provide a production method for obtaining the novel cyclic acetal in a high yield by a simple method.

The present inventors have conducted intensive studies to solve the above problems, and as a result, focused on ether compounds as a structure that does not generate carboxylic acid or carbon dioxide, and ketal or acetal compound having a specific structure has extremely high electrical insulation. The present inventors have found that they have compatibility, and succeeded in achieving both compatibility with hydrofluorocarbon, electrical insulation, and hygroscopicity, which were not compatible with conventional ether compounds, and completed the present invention.

That is, the gist of the present invention is to provide (1) at least one kind of polyhydric alcohol having an even number of valences of 4 to 10 and having no ether bond, and at least one kind of the following compound A or B: A ketalization reaction, an acetalization reaction, a transketalization reaction or a transacetalization reaction, wherein the number of unreacted hydroxyl groups present in the cyclic ketal or the cyclic acetal is a raw material. A synthetic lubricating oil comprising a compound having 2% or less of the number of hydroxyl groups of the polyhydric alcohol, Compound A: a carbonyl compound represented by the general formula (I) (In the formula, R ¹ represents a linear, branched, or cyclic alkyl group having 1 to 18 carbon hydrogen or C, R ² is 1 to the number of carbon atoms
Indicate 18 linear, branched or cyclic alkyl groups. Alternatively, R ¹ and R ² together represent an alkylene group having 2 to 36 carbon atoms. Compound B: ketal or acetal obtained from a carbonyl compound represented by the general formula (I) and a lower alcohol having 1 to 6 carbon atoms, (2) selected from the group consisting of diglycerin, ditrimethylolethane and ditrimethylolpropane One or more polyhydric alcohols and one of the following compounds A or B
With a species or more, a ketal compound, an acetalization reaction, a transketalization reaction or a transacetalization reaction, which is a cyclic ketal or a cyclic acetal obtained by the unreacted hydroxyl group present in the cyclic ketal or the cyclic acetal. A synthetic lubricating oil comprising a compound whose number is 2% or less based on the number of hydroxyl groups of the polyhydric alcohol as a raw material, compound A: a carbonyl compound represented by the general formula (I) (In the formula, R ¹ represents a linear, branched, or cyclic alkyl group having 1 to 18 carbon hydrogen or C, R ² is 1 to the number of carbon atoms
Indicate 18 linear, branched or cyclic alkyl groups. Alternatively, R ¹ and R ² together represent an alkylene group having 2 to 36 carbon atoms. Compound B: a ketal or acetal obtained from a carbonyl compound represented by the general formula (I) and a lower alcohol having 1 to 6 carbon atoms, (3) a valence of not less than 4 and not more than 8 having no ether bond. A cyclic ketal or a cyclic compound obtained by subjecting at least one of the even-numbered polyhydric alcohols to at least one of the following compounds C or D by a ketalization reaction, an acetalization reaction, a transketalization reaction, or a transcasetalization reaction; A synthesis comprising an acetal, wherein the cyclic ketal or the compound in which the number of unreacted hydroxyl groups present in the cyclic acetal is 2% or less with respect to the number of hydroxyl groups of the starting polyhydric alcohol. Lubricating oil, Compound C: carbonyl compound represented by general formula (II) (Wherein, R ³ represents a hydrogen atom or a straight-chain having 1 to 12 carbon atoms, branched, or cyclic alkyl group, R ⁴ is 1 to carbon atoms
Shows 12 linear, branched, or cyclic alkyl groups. Alternatively, R ³ and R ⁴ together represent an alkylene group having 2 to 13 carbon atoms. The total carbon number of R ³ and R ⁴ is 1 to 13. Compound D: ketal or acetal obtained from a carbonyl compound represented by the general formula (II) and a lower alcohol having 1 to 6 carbon atoms, (4) selected from the group consisting of diglycerin, ditrimethylolethane and ditrimethylolpropane One or more polyhydric alcohols and one of the following compounds C or D
A cyclic ketal or a cyclic acetal obtained by performing a ketalization reaction, an acetalization reaction, a transketalization reaction or a transacetalization reaction with at least one species, and an unreacted hydroxyl group present in the cyclic ketal or the cyclic acetal A compound having 2% or less of the number of hydroxyl groups of the raw material polyhydric alcohol, a compound lubricating oil characterized by the following formula: Compound C: carbonyl compound represented by the general formula (II) (Wherein, R ³ represents a hydrogen atom or a straight-chain having 1 to 12 carbon atoms, branched, or cyclic alkyl group, R ⁴ is 1 to carbon atoms
Shows 12 linear, branched, or cyclic alkyl groups. Alternatively, R ³ and R ⁴ together represent an alkylene group having 2 to 13 carbon atoms. The total carbon number of R ³ and R ⁴ is 1 to 13. Compound D: a ketal or acetal obtained from a carbonyl compound represented by the general formula (II) and a lower alcohol having 1 to 6 carbon atoms, (5) a cyclic ketal or a cyclic acetal having 1,3-
The synthetic lubricating oil according to any one of the above (1) to (4), which comprises a dioxolane structure and / or a 1,3-dioxane structure, (6) a formula (IIIa), (IIIb), (IVa) or ( IV
one of the cyclic ketal or cyclic acetal represented by b)
A synthetic lubricating oil characterized by containing at least one species, (Wherein, R ³ represents a hydrogen atom or a straight-chain having 1 to 12 carbon atoms, branched, or cyclic alkyl group, R ⁴ is 1 to carbon atoms
Shows 12 linear, branched, or cyclic alkyl groups. Alternatively, R ³ and R ⁴ together represent an alkylene group having 2 to 13 carbon atoms. The total carbon number of R ³ and R ⁴ is 1 to 13. (7) A synthetic lubricating oil comprising at least one of a cyclic ketal or a cyclic acetal represented by the formula (V) or (VI): (Wherein, R ³ represents a hydrogen atom or a straight-chain having 1 to 12 carbon atoms, branched, or cyclic alkyl group, R ⁴ is 1 to carbon atoms
Shows 12 linear, branched, or cyclic alkyl groups. Alternatively, R ³ and R ⁴ together represent an alkylene group having 2 to 13 carbon atoms. The total carbon number of R ³ and R ⁴ is 1 to 13. (8) a refrigerating machine working fluid composition containing a refrigerating machine oil containing a cyclic ketal or a cyclic acetal according to any one of the above (2) to (7) and a hydrofluorocarbon, (9) a hydrofluorocarbon and a refrigerating machine oil, Refrigerator working fluid composition according to the above (8), containing fluorocarbon / refrigeration oil = 50/1 to 1/20 (weight ratio), (10) the following general formula (i) or (ii) (Wherein, R ⁵ represents a hydrogen atom, in which case R ⁶ has 3 carbon atoms)
Or a linear or branched alkyl group having 4 to 21 carbon atoms. Alternatively, R ⁵ represents a linear or branched alkyl group having 1 to 21 carbon atoms, in which case R ⁶ represents a linear or branched alkyl group having 2 to 21 carbon atoms. Cyclic acetals represented by), (11) R ⁵ is a linear or branched alkyl group having a branched alkyl group or 4 to 12 carbon atoms R ⁶ is 3 carbon hydrogen atom or R ⁵ 1 carbon atoms, wherein R ⁶ in 12 linear or branched alkyl group is a linear or branched alkyl group having 2 to 12 carbon atoms (10) cyclic acetals according, R ⁶ in (12) R ⁵ is a hydrogen atom Is a branched alkyl group having 3 to 12 carbon atoms, or R ⁵ is a linear or branched alkyl group having 1 to 12 carbon atoms, and R ⁶ is a linear or branched alkyl group having 2 to 12 carbon atoms. (13) The cyclic acetal according to any one of the above (10) to (12), wherein the hexahydric alcohol residue is provided by sorbitol, (14) the following cyclic formula (iii): And a general formula (iv) (Wherein, R ⁵ represents a hydrogen atom, in which case R ⁶ has 3 carbon atoms)
Or a linear or branched alkyl group having 4 to 21 carbon atoms. Alternatively, R ⁵ represents a linear or branched alkyl group having 1 to 21 carbon atoms, in which case R ⁶ represents a linear or branched alkyl group having 2 to 21 carbon atoms. The cyclic acetal according to the above (10), represented by the general formula (i) or (ii), wherein the carbonyl compound represented by the formula (1) or a reactive derivative thereof (ketal or acetal) is reacted under an acid catalyst. (15) The method according to (14), wherein the hexahydric alcohol is sorbitol.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to a synthetic lubricating oil containing a specific cyclic ketal or cyclic acetal, and a refrigerator working fluid composition, and a specific structure among these cyclic ketals or cyclic acetals. And those relating to novel compounds. In this specification, for convenience,
The former is referred to as a first invention and the latter is referred to as a second invention, and each of the inventions will be described below. First, the first invention will be described.

The polyhydric alcohol used in the first invention is a polyhydric alcohol having an even valence of 4 to 10 valences. When the valency of the polyhydric alcohol is odd, unreacted hydroxyl groups always remain,
It is not preferable because the viscosity increases. In addition, when used for a refrigerator working fluid, if the hydroxyl groups remain, the compatibility with the hydrofluorocarbon deteriorates, which is not preferable. By converting an unreacted hydroxyl group into an ether structure by an alkylation reaction, the viscosity and compatibility with the hydrofluorocarbon can be improved, but this is not preferable because the number of reaction steps in production increases. In addition, it becomes difficult to obtain a high-purity product. Specifically, erythritol, diglycerin, arabinose, ribose, sorbitol, mannitol,
Galactitol, iditol, talitol, allitol, 4,7-dioxadecane-1,2,9,10-tetraol,
5-methyl-4,7-dioxadecane-1,2,9,10-tetraol, 4,7,10-trioxatridecane-1,2,12,13-
Polyhydric alcohols such as tetraol, 1,6-dimethoxyhexane-2,3,4,5-tetraol, 3,4-diethoxyhexane-1,2,5,6-tetraol and pentaerythritol,
Ditrimethylolethane, ditrimethylolpropane,
Dipentaerythritol, tripentaerythritol,
2,9-diethyl-2,9-dihydroxymethyl-4,7-dioxadecane-1,10-diol, 2,12-diethyl-2,12-
Hindered alcohols such as dihydroxymethyl-5,8-dimethyl-4,7,10-trioxatridecane-1,13-diol. Of these, 4,7-dioxadecane-1,2,9,1
0-tetraol, 5-methyl-4,7-dioxadecane-
1,2,9,10-tetraol, 4,7,10-trioxatridecane-1,2,12,13-tetraol, 1,6-dimethoxyhexane-2,3,4,5-tetraol , 3,4-diethoxyhexane-1,2,5,6-tetraol, 2,9-diethyl-2,9-dihydroxymethyl-4,7-dioxadecane-1,10-diol, 2,12-diethyl -2,12-dihydroxymethyl-5,8
Polyhydric alcohols having two or more ether bonds, such as dimethyl-4,7,10-trioxatridecane-1,13-diol, are not easily available industrially and require several steps in the structure, so they are expensive. Is not preferred.

The polyhydric alcohol used in the first invention has a valence of 4
Valence, hexavalent, octavalent, or pentavalent, preferably tetravalent,
Hexavalent or octavalent, more preferably tetravalent or hexavalent. If the valence is more than 10, the viscosity of the obtained cyclic ketal or cyclic acetal becomes too high. On the other hand, if it is less than tetravalent, the molecular weight becomes too low, and the boiling point and the flash point become undesirably low.

The polyhydric alcohol used in the first invention has 4 carbon atoms.
~ 25, preferably 4-20. When the number of carbon atoms exceeds 25, the viscosity of the obtained cyclic ketal or cyclic acetal becomes too high. In addition, carbon number 4
If it is smaller, the molecular weight is too low, and the boiling point and the flash point are undesirably low.

The polyhydric alcohol used in the first invention is a saturated aliphatic alcohol. It is not preferable to have an unsaturated bond because thermal stability is deteriorated.

The polyhydric alcohol used in the first invention is most preferably one having no ether bond in the molecule, from the viewpoint of having good electric insulating properties. Further, one having an ether bond is preferable. If you have two or more,
When the cyclic ketal or the cyclic acetal of the first invention is used for an electric insulating oil, a working fluid of a refrigerator, or the like, it is not preferable because electric insulation is deteriorated. Specific examples of the polyhydric alcohol having no ether bond in the molecule are erythritol, sorbitol, mannitol, galactitol, iditol, talitol, allitol, pentaerythritol, etc. Specific examples of the polyhydric alcohol having one ether bond are: , Diglycerin, ditrimethylolpropane, ditrimethylolethane, and the like.

When the cyclic ketal or the cyclic acetal of the first invention is used for a refrigerator working fluid, the valency of the polyhydric alcohol is preferably tetravalent, hexavalent, or octavalent, and more preferably tetravalent or hexavalent. It is. If the valency of the polyhydric alcohol is larger than 8, the viscosity becomes too high, and the compatibility with the hydrofluorocarbon deteriorates. On the other hand, if the valency of the polyhydric alcohol is less than 4, the molecular weight becomes too low, and the boiling point and the flash point become low. Also, the carbon number is preferably 4 to 20, more preferably 4 to 20.
15, particularly preferably 4 to 10. If the number of carbon atoms is larger than 20, the compatibility with the hydrofluorocarbon becomes poor, which is not preferable. On the other hand, if the number of carbon atoms is smaller than 4, the molecular weight is too low, and the melting point and the flash point are undesirably low.
In addition, when a highly symmetric alcohol such as pentaerythritol is used, the obtained cyclic ketal or cyclic acetal has a high melting point, which is not preferable as a working fluid for a refrigerator.

The carbonyl compound used in the first invention is a ketone or aldehyde represented by the general formula (I).

The ketone or aldehyde represented by the general formula (I) has 2 to 37 carbon atoms, preferably 2 to 25 carbon atoms, and more preferably 2 to 17 carbon atoms. If the number of carbon atoms exceeds 37, the viscosity of the obtained cyclic ketal or cyclic acetal becomes too high, which is not preferable.

R ¹ represents a hydrogen atom or a linear, branched, or cyclic alkyl group having 1 to 18 carbon atoms, preferably a hydrogen atom or a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms, Preferably a hydrogen atom or carbon number 1
8 represents a linear, branched or cyclic alkyl group. R ²
Represents a linear, branched, or cyclic alkyl group having 1 to 18 carbon atoms, preferably represents a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms, and more preferably has 1 to 8 carbon atoms. Indicates a linear, branched, or cyclic alkyl group. Alternatively, R ¹ and R ² together have ^{2 to} 36 carbon atoms, preferably 2 to 24 carbon atoms, and more preferably 2 to 16 carbon atoms.
Represents an alkylene group. Further, R ¹ and R ² may be the same or different.

When the carbon number of R ¹ or R ² exceeds 18, the viscosity of the obtained cyclic ketal or cyclic acetal becomes too high,
Not preferred. On the other hand, when the number of carbon atoms of the alkylene group formed by combining R ¹ and R ² exceeds 36, the viscosity of the obtained cyclic ketal or cyclic acetal becomes too high, which is not preferable.

Specifically, as a ketone wherein R ¹ and R ² are alkyl groups, acetone, methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl isopropyl ketone, methyl butyl ketone, ethyl propyl ketone, methyl-se
c-butyl ketone, methyl isobutyl ketone, ethyl isopropyl ketone, methyl tert-butyl ketone, methyl amyl ketone, ethyl butyl ketone, diisopropyl ketone, methyl isoamyl ketone, dipropyl ketone,
Isopropyl propyl ketone, methyl neopentyl ketone, ethyl-tert-butyl ketone, methylhexyl ketone, ethyl pentyl ketone, 6-methyl-2-heptanone, 4-methyl-3-heptanone, 2-methyl-3-heptanone, 5-methyl -3-heptanone, methylcyclohexyl ketone, methylheptyl ketone, ethylhexyl ketone, dibutyl ketone, diisobutyl ketone, methyl octyl ketone, methyl nonyl ketone, dipentyl ketone, methyl decyl ketone, methyl undecyl ketone,
Dihexyl ketone, 5- (2 ', 2', 5'-trimethylcyclohexyl) -2-pentanone, 6,10-dimethyl-2
-Undecane, methyl tridecyl ketone, diheptyl ketone, methyl tetradecyl ketone, dioctyl ketone, methyl pentadecyl ketone, diisooctyl ketone, methyl hexadecyl ketone, 6,10,14-trimethyl-2-pentadecanone, dinonyl ketone, methyl Heptadecyl ketone, methyl octadecyl ketone, didecyl ketone and the like can be mentioned.

Examples of the ketone in which R ¹ and R ² together form an alkylene group include cyclopropanone, cyclobutanone,
Cyclopentanone, cyclohexanone, 2-methylcyclopentanone, 3-methylcyclopentanone, 2-methylcyclohexanone, 3-methylcyclohexanone,
-Methylcyclohexanone, cycloheptanone, 2,4-
Dimethylcyclohexanone, 2,6-dimethylcyclohexanone, cyclooctanone, 2-ethylcyclohexanone, 3-ethylcyclohexanone, 4-ethylcyclohexanone, 3,5,5-trimethylcyclohexanone, 2-
tert-butylcyclohexanone, 4-tert-butylcyclohexanone, 2-isopropyl-4-methylcyclohexanone, cyclodecanone, cyclododecanone and the like.

Examples of the aldehyde in which R ¹ is a hydrogen atom include acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, valeraldehyde, isovaleraldehyde, 2-methylbutyraldehyde, caproaldehyde, 2-methylpentanal, and 3-methyl Pentanal, 4-methylpentanal, 2-ethylbutanal, 2,3-dimethylbutanal, 3,3-dimethylbutanal, cyclopentylacetaldehyde, heptanal, 2-methylhexanal, 3-methylhexanal, 4-methylhexanal , 5-methylhexanal, 2-ethylpentanal, cyclohexylacetaldehyde, octanal, 2-methylheptanal, 2
-Ethylhexanal, 2-propylpentanal, 2,
4,4-trimethylpentanal, nonylaldehyde, 3,
5,5-trimethylhexanal, decylaldehyde, isodecylaldehyde, 3,7-dimethyloctanal, 2
-Isopropyl-5-methylhexanal, undecanal, dodecanal, tridecylaldehyde, isotridecylaldehyde, hexadecanal, isooctadecanal, octadecanal, 2-methyloctadecanal and the like.

Further, when the cyclic ketal or the cyclic acetal of the first invention is used as a base oil for a refrigerator working fluid, the ketone or aldehyde represented by the general formula (II) of the general formula (I) is more preferable.

The ketone or aldehyde represented by the general formula (II) has 2 to 25 carbon atoms, preferably 2 to 17 carbon atoms, and more preferably 2 to 11 carbon atoms. When the number of carbon atoms exceeds 25, the compatibility of the obtained cyclic ketal or cyclic acetal with the hydrofluorocarbon is unfavorably deteriorated.

R ³ represents a hydrogen atom or a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms, preferably a hydrogen atom or a linear, branched, or cyclic alkyl group having 1 to 8 carbon atoms, Preferably a hydrogen atom or carbon number 1
5 represents a linear, branched, or cyclic alkyl group. R ⁴
Represents a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms, preferably represents a linear, branched, or cyclic alkyl group having 1 to 8 carbon atoms, and more preferably has 1 to 5 carbon atoms. Indicates a linear, branched, or cyclic alkyl group. Alternatively, R ³ and R ⁴ together represent an alkylene group having 2 to 13 carbon atoms, preferably an alkylene group having 4 to 10 carbon atoms, and more preferably an alkylene group having 4 to 5 carbon atoms. The total number of carbon atoms of R ³ and R ⁴ is 1 to 13, preferably 1 to 10, and more preferably 1 to 5.

If the carbon number of R ³ or R ⁴ exceeds 12, the compatibility of the resulting cyclic ketal or cyclic acetal with the hydrofluorocarbon is undesirably reduced. Also,
The carbon number of the alkylene group formed by R ³ and R ⁴ together is
If it exceeds 13, the compatibility of the obtained cyclic ketal or cyclic acetal with the hydrofluorocarbon becomes poor, which is not preferable. On the other hand, if the total number of carbon atoms of R ³ and R ⁴ exceeds 13, the compatibility of the resulting cyclic ketal or cyclic acetal with hydrofluorocarbons is unfavorably deteriorated.

Further, from the compatibility of the resulting cyclic ketal or cyclic acetal with the hydrofluorocarbon, the alkyl group of R ³ and R ⁴ is preferably a branched or cyclic structure rather than a linear structure,
Further, it is preferable that R ³ and R ⁴ not form together rather than form an alkylene group.

The ketones represented by the general formulas (I) and (II) used in the first invention can be obtained by subjecting a fatty acid to a high-temperature decarboxylation dimerization reaction, an olefin catalytic oxidation reaction (Wacker method), a secondary alcohol oxidation, dehydrogenation, or the like. It can be easily obtained by oxidation of cycloalkane. In the case of the Wacker method, the obtained ketone can be separated and purified into a single product by precision distillation. Also, the first
The aldehydes represented by the general formulas (I) and (II) used in the invention of the invention include, for example, dehydrogenation of fatty alcohols, hydroformylation of olefins (oxo method), Rosemund reduction of fatty acid chlorides and direct hydrogenation of fatty acids. Etc. can be easily obtained. In the case of the oxo method, a linear product and a branched product are produced, but they can be separated and purified into single products by precision distillation.

The reactive derivative of the carbonyl compound used in the first invention includes the above-described ketal and acetal which are easily synthesized from the above-mentioned ketone, aldehyde and lower alcohol having 1 to 6 carbon atoms by an acid catalyst. Carbon number 1
Specific examples of the lower alcohols of Nos. To 6 include methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, tert-butanol, amyl alcohol, isoamyl alcohol, neopentyl alcohol, 1-methylbutanol, 1,1- Dimethylpropanol, 1-ethylpropanol, hexanol, isohexanol, 2-ethylbutanol,
-Methylamyl alcohol, 1,3-dimethylbutanol, 1-ethylbutanol and the like.

The cyclic ketal and the cyclic acetal of the first invention can be obtained as follows. The reaction between the polyhydric alcohol and the above ketone is a ketalization reaction, and this reaction is performed using p-toluenesulfonic acid, methanesulfonic acid,
An acid catalyst such as sulfuric acid is used in an amount of 0.1 to 10 mol%, preferably 1.0 to 7.0 mol%, more preferably 1.
This is performed using 0 to 5.0 mol%. This reaction is carried out in the absence of a solvent, or in an inert solvent such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, ligroin, or petroleum ether, or in a mixed solution thereof, with the boiling point of the ketone used. It is preferably carried out at a temperature of from 40 to 130 ° C., preferably from 60 to 100 ° C. while removing generated water. In some cases, it is effective to carry out the reaction under reduced pressure. If the temperature is lower than this, the reaction does not proceed. Further, under a nitrogen flow condition, any of a nitrogen atmosphere and a dry air atmosphere may be used. The reaction time can vary depending on various conditions, but is usually preferably 5 to 200 hours. The resulting cyclic ketal is neutralized, filtered,
Pretreatment such as washing is performed, and then purification can be performed by operations such as clay treatment, crystallization, and distillation.

The reaction between the polyhydric alcohol and the aldehyde is an acetalization reaction.In this reaction, an acid catalyst such as paratoluenesulfonic acid, methanesulfonic acid, or sulfuric acid is used as a catalyst in an amount of 0.01 to 5.0 mol based on the polyhydric alcohol. %, Preferably 0.1 to 2.0 mol%. This method uses no solvent, or an inert solvent such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, butane, ligroin, or petroleum ether, or a mixed solvent of these solvents. 20-130 ° C, preferably 40 ° C, depending on the boiling point
It is preferred to carry out while removing the water formed at a temperature of 〜100 ° C. In some cases, it is effective to carry out the reaction under reduced pressure. When the temperature is low, the reaction does not proceed, and when the temperature is high, coloring is severe and a side reaction occurs. Further, under nitrogen flow conditions, any of a nitrogen atmosphere and a dry air atmosphere may be used. The reaction time may vary depending on various conditions, but is usually preferably 1 to 30 hours. After the obtained cyclic acetal is neutralized, it is subjected to pretreatments such as filtration and washing, and thereafter, clay treatment, crystallization,
It can be purified by an operation such as distillation.

The reaction between a polyhydric alcohol and a ketal, which is a reactive derivative of a ketone, is a transketalization reaction. for
It is carried out using 0.1 to 10 mol%, preferably 1.0 to 7.0 mol%, more preferably 1.0 to 5.0 mol%. This reaction is carried out in the absence of a solvent or in an inert solvent such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, ligroin, petroleum ether, or a mixed solvent thereof to produce a ketal. 40-150, depending on the boiling point of lower alcohol
C., preferably 70-130.degree. C., preferably while removing the lower alcohol formed. In some cases,
It is also effective to carry out the reaction under reduced pressure. If the temperature is lower than this, the reaction does not proceed. Further, under a nitrogen flow condition, any of a nitrogen atmosphere and a dry air atmosphere may be used. The reaction time can vary depending on various conditions, but is usually preferably 5 to 200 hours. After the obtained cyclic ketal is neutralized, it is subjected to pretreatments such as filtration and washing, and then purified by operations such as clay treatment, crystallization, and distillation.

The reaction between polyhydric alcohol and acetal, which is a reactive derivative of aldehyde, is a transacetalization reaction.
The reaction is carried out using an acid catalyst such as methanesulfonic acid or sulfuric acid in an amount of 0.01 to 5.0 mol%, preferably 0.1 to 2.0 mol%, based on the polyhydric alcohol. This method uses no solvent or an inert catalyst such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, butane, ligroin, petroleum ether, or an acetal used in a mixed solvent thereof. Although it depends on the boiling point of the lower alcohol to be formed, it is preferably 20 to 150 ° C, preferably 5 to
It is preferable to carry out at a temperature of 0 to 130 ° C. while removing the lower alcohol generated. In some cases, it is effective to carry out the reaction under reduced pressure. When the temperature is low, the reaction does not proceed, and when the temperature is high, coloring is severe and a side reaction occurs. Further, under nitrogen flow conditions, any of a nitrogen atmosphere and a dry air atmosphere may be used. The reaction time may vary depending on various conditions, but is usually preferably 1 to 30 hours. After the obtained cyclic acetal is neutralized, it is subjected to pretreatments such as filtration and washing, and then purified by operations such as clay treatment, crystallization, and distillation.

The ratio of the ketone to be reacted with the polyhydric alcohol or the ketal which is a reactive derivative of the ketone, or the aldehyde or the acetal which is a reactive derivative of the aldehyde (hereinafter abbreviated as a carbonyl compound) is such that the carbonyl compound is used per mole of the polyhydric alcohol. A / 2 moles (A is the valency of the polyhydric alcohol). In order to increase the reaction rate, it is also effective to carry out the reaction using a carbonyl compound in excess of A / 2 mol, and to remove the excess carbonyl compound after completion of the reaction.

The cyclic ketal or cyclic acetal of the first invention is reacted with one or more polyhydric alcohols and one or more ketones or ketals that are reactive derivatives of ketones or acetal that is a reactive derivative of aldehydes. Obtainable. Moreover, the cyclic ketal or cyclic acetal obtained individually can also be used in mixture. For example, a cyclic ketal obtained from 1 mol of sorbitol and 3 mol of methyl ethyl ketone (40
Cyclic ketal obtained from 1 mol of diglycerin and 2 mol of methyl ethyl ketone (viscosity of 63.1 mm ² / s).
69 mm ² / s) can be individually synthesized, and the two can be mixed to adjust the desired viscosity. As a specific example, a lubricating oil of VG22 can be obtained by mixing 1 mol of cyclic ketal obtained from 1 mol of sorbitol and 3 mol of methyl ethyl ketone, 1 mol of cyclic ketal obtained from 1 mol of diglycerin and 2 mol of methyl ethyl ketone. . Alternatively, the above mixture can be obtained by reacting 1 mol of sorbitol, 1 mol of diglycerin and 5 mol of methyl ethyl ketone. The cyclic ketal or cyclic acetal of the first invention can also be obtained by reacting 1 mol of sorbitol with 2 kinds of ketones or aldehydes, for example, 2 mol of 3,5,5-trimethylhexanal and 1 mol of methyl ethyl ketone.

Further, it is preferable that the obtained cyclic ketal and the cyclic acetal have a small number of unreacted hydroxyl groups in the cyclic acetal. It is preferably at most 10%, more preferably at most 5%, particularly preferably at most 3%. If unreacted hydroxyl groups exceeding 20% remain, the viscosity becomes too high and the boiling point and the flash point become too low, which is not preferable. When this cyclic ketal or cyclic acetal is used as the base oil of a refrigerator working fluid, the unreacted hydroxyl group is preferably as small as possible, particularly preferably 10% or less, and more preferably 5% or less.
Or less, more preferably 3% or less, particularly preferably 2%
Or less, most preferably 1% or less. If unreacted hydroxyl groups exceeding 10% remain, the compatibility with hydrofluorocarbons and the electrical insulation are poor, which is not preferable.

When the cyclic ketal or the cyclic acetal of the first invention is used as an electric insulating oil or a base oil of a working fluid for a refrigerator, a polyhydric alcohol having a structure having no ether bond is preferable because of its high electric insulation. Therefore, sorbitol,
Cyclic ketals and cyclic acetals obtained from hexahydric alcohols such as mannitol, galactitol, iditol, talitol, and allyl, and polyhydric alcohols such as erythritol can be obtained from alcohols having one ether bond such as diglycerin and ditrimethylolpropane. It is more preferable than the obtained cyclic ketal or cyclic acetal.

Further, when the cyclic ketal or the cyclic acetal of the first invention is used as an electric insulating oil or a base oil of a refrigerator working fluid,
Those containing a dioxolane structure and / or a 1,3-dioxane structure are preferred for increasing electrical insulation. Among them, those containing a 1,3 dioxolane structure are particularly preferable. Therefore, it is preferable to use an alcohol having a hydroxyl group at an adjacent position such as erythritol, diglycerin, sorbitol, mannitol, galactitol, iditol, talitol, and allitol. When hexahydric alcohols such as sorbitol, mannitol, galactitol, iditol, thallitol, and allitol are used, cyclic ketals and cyclic acetals represented by Formula IIIa and Formula IIIb can be obtained, but three 1,3-dioxolanes Formula IIIa having a structure is preferred because of its higher electrical insulation. In addition, when erythritol is used, cyclic ketals and cyclic acetals shown in Formula IVa and Formula IVb are obtained, but Formula IVa having two 1,3-dioxolane structures has higher electrical insulation. Therefore, it is preferable. Sorbitol, mannitol, galactitol, iditol,
Hexahydric alcohols such as talitol and allitol and erythritol can be reacted with ketones or ketals of formula III
a, the cyclic ketal of the formula IVa is easily formed, and when reacted with an aldehyde or an acetal, the cyclic acetal of the formula IIIb or the formula IVb is easily formed. Therefore, it is preferable to react these alcohols with ketones or ketals.

When the cyclic ketal or the cyclic acetal of the first invention is used as the base oil of the working fluid for the refrigerator, the cyclic ketal or the cyclic ketal of the hexahydric alcohol represented by the formula (III) among the polyhydric alcohols having an even valency may be used. Acetal, erythritol, diglycerin represented by formulas (IV) to (VI),
Cyclic ketals and cyclic acetals obtained from tetrahydric alcohols such as ditrimethylolpropane are particularly preferred because they have various physical properties such as compatibility with hydrofluorocarbons, electrical insulation, melting point and viscosity.
Even with the same tetrahydric alcohol, the formula (VIIa) or (VIIb)
Both of the cyclic ketals obtained from pentaerythritol having good symmetry are not preferable because they become solid at room temperature. Among the compounds represented by the formulas (III) to (VI), (IIIa), (IIIb), and (IV) having a 1,3-dioxolane structure
The compounds shown in a) and (V) are preferable, and among them,
(IIIa) having only 1,3-dioxolane structure (IIIa), (IV
a) and (V), among which the polyhydric alcohol moiety has no ether bond (IIIa), (IV)
The compounds shown in a) are preferred.

The melting point of the cyclic ketal or cyclic acetal of the first invention is
It is preferably at most 10 ° C, more preferably at most -10 ° C, particularly preferably at most -30 ° C. (VIIa), (VIIb)
It is not preferable to use a cyclic ketal or a cyclic acetal having a melting point of more than 10 ° C. alone as a lubricating oil, but other cyclic ketals or cyclic acetals of the first invention having a low melting point or other lubricating oils And can be used by limiting the amount added.

The cyclic ketal or cyclic acetal used in the first invention has a viscosity at 100 ° C. of preferably 1 mm ² / s or more and 100 mm ² / s or less, more preferably 1 mm ² / s or more and 50 mm ² / s or less, particularly preferably. 1 mm ² / s or more, or less 30 mm ² / s.

When the cyclic ketal or the cyclic ketal used in the first invention is used as a base oil of a refrigerator working fluid, the two-phase separation temperature with hydrofluorocarbon is desirably low, and is preferably 10 ° C. or less, more preferably 0 ° C. or less. The temperature is more preferably -10 ° C or lower, particularly preferably -30 ° C or lower.

The cyclic ketal or cyclic acetal of the first invention can be used by mixing with other lubricating oils. Other lubricating oils include mineral oils, polybutenes, polyalphaolefins, hydrocarbon synthetic oils such as alkylbenzenes, aliphatic diesters and neopentyl polyol esters, polyalkylene glycols, polyphenyl ethers, carbonates, phosphate esters, silicate esters, and silicones. Examples include oils and perfluoropolyethers, and specific examples are “New Edition Lubrication Physical Chemistry” (Koshobo) and “Basics and Applications of Lubricating Oils”.
(Corona).

The mixing ratio of the cyclic ketal or the cyclic acetal of the first invention to the other lubricating oil is such that the cyclic ketal or the cyclic acetal is 0.1% by weight or more, preferably 1.0% by weight in the mixed lubricating oil.
The content is more preferably at least 5.0% by weight, particularly preferably at least 10% by weight. The amount included
If the amount is less than 0.1% by weight, the effect of improving lubricity and the effect of preventing hydrolysis of esters, carbonates and the like cannot be sufficiently exhibited. When the cyclic ketal or cyclic acetal of the first invention is used as a base oil of a refrigerator working fluid, the other lubricating oil to be mixed is preferably one having excellent compatibility with hydrofluorocarbon, and neopentyl polyol ester or Polyalkylene glycol, carbonate and the like are preferred. However, when the compatibility of the cyclic ketal and the cyclic acetal of the first invention with the hydrofluorocarbon is sufficiently excellent, for example, when the two-phase separation temperature is -30 ° C or less, preferably -50 ° C or less, Can be mixed with a lubricating oil having inferior compatibility, such as alkylbenzene or mineral oil, in a range where the two-phase separation temperature does not exceed 10 ° C.

Since the cyclic ketal and the cyclic acetal of the first invention have excellent compatibility with hydrofluorocarbon and excellent electrical insulation, they can be used as a mixture with hydrofluorocarbon for a refrigerator operating object. Further, since it has excellent electric insulation properties, it can be used for electric insulating oil. Further, since it has a ring structure in the molecule, it can be used for traction oil. In addition, because of its excellent lubricity and heat resistance, engine oil, turbine oil, gear oil, hydraulic oil,
It can be used for bearing oil, metal working oil, compressor oil, grease base oil and the like. Further, since it has excellent lubricity, it can be used as an additive for low sulfur gas oil. Further, since the molecule further contains many oxygen atoms, it can be used as a fuel oil additive such as octane number booster.

When the cyclic ketal or cyclic acetal of the first invention is used for a refrigerator working fluid, the mixing ratio of the hydrofluorocarbon in the refrigerator working fluid composition of the present invention to the refrigerator oil containing the cyclic ketal or cyclic acetal used in the present invention is used. Is usually hydrofluorocarbon / refrigeration oil = 50/1 ~
It is 1/20 (weight ratio), preferably 10/1 to 1/5 (weight ratio). If the ratio of hydrofluorocarbon / refrigerating oil is higher than 50/1, the viscosity of the hydrofluorocarbon-refrigerating oil mixed solution becomes low, and the lubricity may deteriorate, which is not preferable. On the other hand, if the ratio of hydrofluorocarbon is lower than 1/20 of hydrofluorocarbon / refrigeration oil, the refrigerating capacity may be insufficient, which is not preferable.

The hydrofluorocarbon used in the first invention is difluoromethane (HFC32), 1,1-difluoroethane (HFC152a), 1,1,1-trifluoroethane (HFC143).
a), 1,1,1,2-tetrafluoroethane (HFC134a),
1,2,2-tetrafluoroethane (HFC134), pentafluoroethane (HFC125) and the like, particularly 1,1,1,2-tetrafluoroethane, difluoromethane, pentafluoroethane, 1,1,1-triene Fluoroethane is preferred. These hydrofluorocarbons may be used alone,
Two or three or more types of hydrofluorocarbons may be mixed and used.

The cyclic ketal and the cyclic acetal of the first invention include, as necessary, an antioxidant, an extreme pressure agent, an oiliness improver, an antifoaming agent, a cleaning dispersant, a viscosity index improver, a rust inhibitor,
Lubricating oil additives such as demulsifiers can also be added. For example, those which can be used as antioxidants are 2,6-di-
t-butylphenol, 2,6-di-t-butyl-4-methylphenol, 4,4'-methylenebis (2,6-di-t-
Phenolic antioxidants such as butylphenol), p,
p-dioctylphenylamine, monooctyldiphenylamine, phenothiazine, 3,7-dioctylphenothiazine, phenyl-1-naphthylamine, phenyl-2
Amine antioxidants such as naphthylamine, alkylphenyl-1-naphthylamine and alkylphenyl-2-naphthylamine; sulfur antioxidants such as alkyl disulfide, thiodipropionate and benzothiazole; zinc dialkyldithiophosphate And zinc diaryldithiophosphate. The addition amount is 0.05 to the lubricating oil containing a cyclic ketal or a cyclic acetal of the first invention.
~ 2.0% by weight.

Extreme pressure agents, those which can be used as an oiliness improver include, for example, zinc compounds such as zinc dialkyldithiophosphate, zinc diaryldithiophosphate, thiodipropionate, dialkylsulfide, dibenzylsulfide, dialkylpolysulfide, alkylmercaptan, and dibenzo. Sulfur compounds such as thiophene and 2,2'-dithiobis (benzothiazole); phosphorus compounds such as triaryl phosphate and triaryl phosphite; trialkyl phosphite and trialkyl phosphate; chlorinated compounds such as chlorinated paraffin; molybdenum Dithiocarbamate, molybdenum dithiophosphate, molybdenum compounds such as molybdenum disulfide, perfluoroalkyl polyether, and trifluoroethylene chloride polymer,
Fluorine compounds such as fluorinated graphite; silicon compounds such as fatty acid-modified silicone; and graphite. The addition amount is 0.05 to 10% by weight based on the lubricating oil containing the cyclic ketal or the cyclic acetal of the first invention.

Those used as antifoaming agents include silicone oils such as dimethylpolysiloxane, and organosilicones such as diethylsilicone. The amount of addition is 0.005 with respect to the lubricating oil containing the cyclic ketal or the cyclic acetal of the first invention.
05 to 1% by weight.

Those used as detergent dispersants include sulfonates, phenates, salicylates, phosphonates, polybutenylsuccinimides, polybutenylsuccinates, and the like. The addition amount is 0.05 to 10% by weight based on the lubricating oil containing the cyclic ketal or the cyclic acetal of the first invention.

When the cyclic ketal or the cyclic acetal of the first invention is used for a refrigerator working fluid, benzotriazole and / or a benzotriazole derivative for protecting a metal surface is added as an additive, or lubricity is improved. It is effective to add a triaryl phosphate and / or a triaryl phosphite, or to add a phenolic compound having a radical trapping ability for improving thermal stability or a metal deactivator having a chelating ability.

The triaryl phosphate or triaryl phosphite used in the first invention has 18 to 70 carbon atoms, and more preferably has 18 to 50 carbon atoms.
Specifically, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, xyenyl diphenyl phosphate, tris (tribromophenyl) phosphate, tris (dibromophenyl) phosphate Triaryl phosphates such as phosphate, tris (2,4-di-t-butylphenyl) phosphate, and trinonylphenyl phosphate; triphenyl phosphite, tricresyl phosphite, trixylenyl phosphite, and cresyl Diphenyl phosphite, xylenyl diphenyl phosphite, tris (2,4-di-
triarylphosphites such as t-butylphenyl) phosphite, trinonylphenylphosphite, tris (tribromophenyl) phosphite and tris (dibromophenyl) phosphite; Zyl phosphate, trixylenyl phosphate, tris (2,4-di-t-butylphenyl) phosphate, triphenyl phosphite, tricresyl phosphite, trixylenyl phosphite, tris (2,4-di -T-butylphenyl) phosphite. The amount of the triaryl phosphate and / or triaryl phosphite to be added is usually 0.1 to 5.0% by weight, preferably 0.5 to 2.0% by weight, based on the lubricating oil containing the cyclic ketal or the cyclic acetal of the first invention. is there.

The amount of the benzotriazole and / or benzotriazole derivative used in the first invention is usually 0.1% based on the lubricating oil containing a cyclic ketal or a cyclic acetal of the present invention.
001-0.1% by weight, preferably 0.003-0.03% by weight
It is. The benzotriazole and benzotriazole derivative used in the present invention have 6 to 50 carbon atoms, preferably 6 to 30 carbon atoms. Specifically, benzotriazole, 5-methyl-1H-benzotriazole, 1-dioctylaminomethylbenzotriazole,
1-dioctylaminomethyl-5-methylbenzotriazole, 2- (5'-methyl-2'-hydroxyphenyl) benzotriazole, 2- [2'-hydroxy-
3 ', 5'-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- (3', 5'-di-
t-butyl-2'-hydroxyphenyl) benzotriazole, 2- (3'-t-butyl-5'-methyl-2 '
-Hydroxyphenyl) -5-chlorobenzotriazole, 2- (3 ', 5'-di-tert-butyl-2'-hydroxyphenyl) -5-chlorobenzotriazole, 2-
(3 ', 5'-di-t-amyl-2'-hydroxyphenyl) benzotriazole, 2- (5'-t-butyl-
2'-hydroxyphenyl) benzotriazole, 2-
(2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5'-t-octylphenyl) benzotriazole, 2- [2'-hydroxy-3 '-(3 ", 4 ", 5", 6 "-tetrahydrophthalimidomethyl) -5'-methylphenyl] benzotriazole and the like, preferably benzotriazole,
5-methyl-1H-benzotriazole and the like.

The amount of the metal deactivator used in the first invention is usually 0.001 to 2.0% by weight, preferably 0.003 to 2.0% by weight based on the lubricating oil containing the cyclic ketal or the cyclic acetal of the present invention.
~ 0.5% by weight. The metal deactivator used in the present invention preferably has chelating ability and has 5 to 50 carbon atoms, preferably 5 to 20 carbon atoms. Specifically, N,
N'-disalicylidene-1,2-diaminoethane, N, N'-
Disalicylidene-1,2-diaminopropane, N-salicylidene-N'-dimethyl-1,2-diaminoethane, N, N '
-Disalicylidenehydrazine, N, N'-bis (α, 5-dimethylsalicylidene) -1,2-diaminoethane, N, N'-
Bis (α, 5-dimethylsalicylidene) -1,3-propanediamine, N, N′-bis (α, 5-dimethylsalicylidene) -1,6-hexanediamine, N, N′-bis ( α, 5-dimethylsalicylidene) -1,10-decanediamine, N, N ′
-Bis (α, 5-dimethylsalicylidene) ethylenetetramine, salicylaldoxime, 2-hydroxy-5-methylacetophenoxime, acetylacetone, ethyl acetoacetate, acetoacetate-2-ethylhexyl, dimethyl malonate, diethyl malonate 2-ethylhexyl malonate, anthranilic acid, nitrilotriacetic acid, didroxyethylglycine, hydroxyethylethylenediaminetriacetic acid, hydroxyethyliminodiacetic acid, ethylenediamine, 3-mercapto-1,2-propanediol, alizarin, quinizarin, mercaptobenzo Thiazole and the like, preferably N, N'-disalicylidene-1,2-diaminoethane, N, N'-disalicylidene-1,2-diaminopropane, acetylacetone, acetoacetate, alizarin, quinizarin and the like. You.

The amount of the phenolic compound having a radical trapping ability used in the first invention is usually 0.05 to 2.0 with respect to the lubricating oil containing the cyclic ketal or the cyclic acetal of the present invention.
%, Preferably 0.05 to 0.5% by weight. The phenolic compound used in the present invention has 6 to 6 carbon atoms.
100, preferably 10-80. Specifically, 2,6-di-t-butylphenol, 2,6-di-
t-butyl-4-methylphenol, 4,4'-methylenebis (2,6-di-t-butylphenol), 4,4'-butylidenebis (3-methyl-6-t-butylphenol), 2,2'- Methylenebis (4-ethyl-6-t-butylphenol), 2,2'-methylenebis (4-methyl-6-t-butylphenol), 4,4'-isopropylidenebisphenol, 2,4-dimethyl-6-t- Butylphenol, tetrakis [methylene-3- (3,5-di-
t-butyl-4-hydroxyphenyl) propionate] methane, 1,1,3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane, 1,3,5-trimethyl-2,4, 6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, 2,2'-dihydroxy-
3,3'-di (α-methylcyclohexyl) -5,5'-dimethyl-diphenylmethane, 2,2'-isobutylidenebis (4,6-dimethylphenol), bis [3,3-bis-
(4'-hydroxy-3'-t-butylphenyl) butyric acid glycol ester, 2,6-bis (2 '
-Hydroxy-3'-tert-butyl-5'-methylbenzyl) -4-methylphenol, 1,1'-bis (4-hydroxyphenyl) cyclohexane, 2,5-di-tert-amylhydroquinone, 2,5 -Di-t-butylhydroquinone,
1,4-dihydroxyanthraquinone, 3-t-butyl-
4-hydroxyanisole, 2-tert-butyl-4-hydroxyanisole, 2,4-dibenzoylresorcinol, 4-tert-butylcatechol, 2,6-di-tert-butyl-4-ethylphenol, 2-hydroxy- 4-methoxybenzophenone, 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,4,5-trihydroxybenzophenone, α-tocopherol, bis [2- (2-hydroxy-5-methyl -3-tert-butylbenzyl) -4-methyl-6-tert-butylphenyl] terephthalate, triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1 , 6-hexanediol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 3,9-bis [2
-(3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl]-
2,4,8,10-tetraoxaspiro [5.5] undecane and the like, preferably, 2,6-di-t-butylphenol, 2,6-di-t-butyl-4-methylphenol, 4,
4'-methylenebis (2,6-di-t-butylphenol), 4,4'-butylidenebis (3-methyl-6-t-
Butylphenol), 2,2'-methylenebis (4-ethyl-6-t-butylphenol), 2,2'-methylenebis (4-methyl-6-t-butylphenol), 4,4 '
-Isopropylidenebisphenol, 2,4-dimethyl-
6-t-butylphenol, tetrakis [methylene-3
-(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate] methane, 1,1,3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane,
1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 2,6-di-
t-butyl-4-ethylphenol, 2,6-bis (2 ′
-Hydroxy-3'-t-butyl-5'-methylbenzyl) -4-methylphenol, bis [2- (2-hydroxy-5-methyl-3-t-butylbenzyl) -4-methyl-6-t -Butylphenyl] terephthalate, triethylene glycol-bis [3- (3-t-butyl-5)
-Methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3,5-di-
t-butyl-4-hydroxyphenyl) propionate] and the like.

Further, an additive such as an organic tin compound or a boron compound for stabilizing the CFC refrigerant may be added. The amount of addition is 0.001 to 10% by weight based on the lubricating oil containing the cyclic ketal or the cyclic acetal of the first invention.

 Next, the second invention will be described.

Among the cyclic ketal and the cyclic acetal in the first invention, the compounds represented by the formulas (IIIa) and (IIIb) are novel compounds, and the cyclic acetals including these compounds (general formula (i) Or, the invention relating to the compound (ii) is described below as a second invention.
In the second invention, the cyclic ketal and the cyclic acetal referred to in the first invention are collectively indicated as "cyclic acetal".

(Wherein, R ⁵ represents a hydrogen atom, in which case R ⁶ has 3 carbon atoms)
Or a linear or branched alkyl group having 4 to 21 carbon atoms. Alternatively, R ⁵ represents a linear or branched alkyl group having 1 to 21 carbon atoms, in which case R ⁶ represents a linear or branched alkyl group having 2 to 21 carbon atoms. In the compound represented by formula (i) or (ii), specific examples of the hexahydric alcohol that gives a hexahydric alcohol residue include the following hexahydric alcohols. That is, sorbitol, mannitol, galactitol, iditol, talitol, and allitol, which are hexitols obtained by reduction of hexose.

Of these, sorbitol is most preferred in terms of availability and price.

In the general formula (i) or (ii), when R ⁵ is a hydrogen atom, R ⁶ is a branched alkyl group having 3 carbon atoms, or 4 to 4 carbon atoms.
A linear or branched alkyl group having 21 carbon atoms, preferably a branched saturated alkyl group having 3 carbon atoms or a saturated linear or branched alkyl group having 4 to 12 carbon atoms, and more preferably a branched saturated alkyl group having 3 to 12 carbon atoms. Is a saturated alkyl group.

The branched alkyl group having 3 carbon atoms represented by R ⁶ is specifically an isopropyl group.

Specific examples of the linear or branched alkyl group having 4 to 21 carbon atoms include the following.

That is, as a linear alkyl group, butyl, pentyl, hexyl, heptyl, octyl, nonyl, undecyl, tridecyl, pentadecyl,
Examples include a heptadecyl group, a nonadecyl group, and a heneicosyl group.

Examples of the α-methyl branched alkyl group include a 1-methylpropyl group, a 1-methylbutyl group, a 1-methylpentyl group, a 1-methylhexyl group, a 1-methylheptyl group,
-Methyloctyl group, 1-methylnonyl group, 1-methyldecyl group, 1-methylundecyl group, 1-methyloctadecyl group and the like.

Examples of the α-branched alkyl group include a 1-ethylpropyl group, a 1-ethylbutyl group, a 1-ethylpentyl group,
Propylbutyl group, 1-ethylhexyl group, 1-propylpentyl group, 1-ethylheptyl group, 1-propylhexyl group, 1-butylpentyl group, 1-pentylhexyl group, 1-hexylheptyl group, 1-octylnonyl group , 1-hexylundecyl group, 1-decylundecyl group and the like.

Examples of the α-multibranched alkyl group in which one or more branches exist in addition to the α-branch and the α-branch include 1,2-
Dimethylpropyl group, 1,2-dimethylbutyl group, 1,3-dimethylbutyl group, 1-ethyl-2-methylpropyl group,
Diisopropylmethyl group, 1,4-dimethylpentyl group,
1-isopropylbutyl group, 1,3,3-trimethylbutyl group, 1,5-dimethylhexyl group, 1-ethyl-2-methylpentyl group, 1-butyl-2-methylpropyl group, 1
-Ethyl-3-methylpentyl group, diisobutylmethyl group, 1,5,9-trimethyldecyl group and the like.

Examples of the β-branched alkyl group include a 2-methylpropyl group, a 2-methylbutyl group, a 2-methylpentyl group,
Examples thereof include an ethylbutyl group, a 2-methylhexyl group, a 2-ethylpentyl group, a 2-methylheptyl group, a 2-ethylhexyl group, and a 2-propylpentyl group.

As a β-multibranched alkyl group having one or more branches other than β-branch, α-branch and β-branch, 2,3-dimethylbutyl group and 2,4,4-trimethylpentyl group And 2-isopropyl-5-methylhexyl group.

Other branched alkyl groups having one or more branches other than the α-branch and β-branch include a 3-methylbutyl group, a 3-methylpentyl group, a 4-methylpentyl group, and a 3,3-dimethyl group. Butyl group, 3-methylhexyl group, 4-methylhexyl group, 5-methylhexyl group, 3,
Examples thereof include a 5,5-trimethylhexyl group, an isodecyl group, a 3,7-dimethyloctyl group, and an isoheptadecyl group.

Examples of the alkyl group in which a hydrogen atom does not exist at the α-position and the α-position has a tertiary carbon include 1,1-dimethylethyl, 1-methylcyclopropyl, and 1,1-dimethylpropyl. 1-methylcyclobutyl group, 1,1-dimethylbutyl group, 1,1,2-trimethylpropyl group, 1-methylcyclopentyl group, 1,1-dimethylpentyl group, 1-methyl-1-ethylbutyl group, 1 , 1-diethylpropyl group,
Examples thereof include a 1,1-diethylbutyl group.

Alkyl groups having no hydrogen atom at the β-position and having a tertiary carbon at the β-position include 2,2-dimethylpropyl, 2,2-dimethylbutyl, and 1,2,2- Trimethylpropyl group, 1-ethyl-2,2-dimethylpropyl group, 2,2-
Examples thereof include a dimethylpentyl group and a 2,3-dimethyl-2-isopropylbutyl group.

No hydrogen atom is present in both the α-position and β-position,
As an alkyl group having a tertiary carbon in both positions,
Examples thereof include a 1,1,2,2-tetramethylpropyl group, a 1,1,2,2-tetramethylbutyl group, and a 1,1,2,2-tetramethylhexyl group.

In the general formula (i) or (ii), when R ⁵ is a linear or branched alkyl group having 1 to 21 carbon atoms,
R ⁶ is a linear or branched alkyl group having 2 to 21 carbon atoms. Preferably, R ⁵ is a linear or branched saturated alkyl group having 1 to 12 carbon atoms, in which case, R ⁶ may be a linear or branched saturated alkyl group having 2 to 12 carbon atoms. preferable.

In the above case, as the linear or branched alkyl group having 1 to 21 carbon atoms represented by R ⁵ , specifically, in addition to the specific examples of the linear or branched alkyl group having 4 to 21 carbon atoms described above, , A methyl group, an ethyl group, a propyl group, and an isopropyl group.

As the straight-chain or branched alkyl group having 2 to 21 carbon atoms represented by R ⁶ , specifically, the above-described C 4 -C 4
In addition to the specific examples of the straight-chain or branched alkyl groups of Nos. 21 to 21, an ethyl group, a propyl group and an isopropyl group may be mentioned.

Examples of the cyclic acetal represented by the general formula (i) or (ii) as described above include the following specific examples (compound names and structural formulas), but are not limited thereto. Absent.

The above cyclic acetal can be suitably produced by the production method of the second invention, but is not limited thereto.

Further, the cyclic acetal of the second invention is used as a polar oil, an organic solvent, a lubricant, a synthetic lubricating oil, a refrigerating machine oil, etc., and a surfactant, an organic solvent, a polar oil, a synthetic lubricating oil, a refrigerating machine oil, etc. Useful as an intermediate.

Next, a method for producing a cyclic acetal of the second invention will be described.

The production method of the present invention is characterized by reacting a hexahydric alcohol with a carbonyl compound (ketone or aldehyde) or a reactive derivative thereof (ketal or acetal) under an acid catalyst.

 The reaction formula of the reaction is as follows.

(In the formula, R ⁵ and R ⁶ have the same meaning as described above. R ⁷ represents a linear or branched alkyl group having 1 to 6 carbon atoms.) That is, sorbitol represented by the formula (iii) Dehydration or dealcoholation reaction of a hexahydric alcohol such as mannitol with a carbonyl compound represented by the general formula (iv) such as a ketone or aldehyde, or a reactive derivative thereof using an acid catalyst. The cyclic acetal of the formula (i) or (ii) is obtained. When a ketone is used, general formula (i) is mainly obtained, and when an aldehyde is used, it is obtained by a mixture of general formulas (i) and (ii). Among the aldehydes, those of α-branched alkyl have a high content of the general formula (i). Further, the content of the general formula (ii) increases in a short reaction time.

The hexahydric alcohol used is represented by the above formula (ii)
Examples of i) include sorbitol, mannitol, galactitol, iditol, talitol, and allitol, which are hexitols obtained by reduction of hexol. Of these, sorbitol is most preferred in terms of availability and price.

Among the carbonyl compounds used in the method of the second invention, there are ketones and aldehydes. Of these, ketones are used for the high-temperature decarboxylation dimerization of fatty acids, the catalytic oxidation of olefins (Wacker method), and the oxidation of secondary alcohols. , Dehydrogenation or oxidation of cycloalkanes. In the case of the Wacker method, the obtained ketone has a distribution, but can be separated and purified into a single product by precision distillation. Specific examples of ketones are as follows, but are not necessarily limited thereto.

For example, methyl alkyl ketone includes methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, methyl amyl ketone, methyl hexyl ketone, methyl heptyl ketone, methyl octyl ketone, methyl nonyl ketone, methyl undecyl ketone, methyl heptadecyl ketone, and the like.

As dialkyl ketones, diethyl ketone, ethyl propyl ketone, ethyl butyl ketone, dipropyl ketone,
Ethyl pentyl ketone, ethyl hexyl ketone, dibutyl ketone, dipentyl ketone, dihexyl ketone, diundecyl ketone, diheptadecyl ketone, and the like.

As hyperbranched ketones, methyl isopropyl ketone, methyl-sec-butyl ketone, methyl isobutyl ketone,
Ethyl isopropyl ketone, methyl tert-butyl ketone, diisopropyl ketone, methyl isoamyl ketone, isopropyl propyl ketone, methyl neopentyl ketone, ethyl tert-butyl ketone, 6-methyl-2
-Heptanone, 4-methyl-3-heptanone, 2-methyl-3-heptanone, 5-methyl-3-heptanone, diisobutyl ketone, 6,10-dimethyl-2-undecanone and the like.

The aldehyde used can be easily obtained by, for example, a dehydrogenation reaction of a fatty alcohol, a hydroformylation reaction of an olefin (oxo method), a Rosemund reduction of a fatty acid chloride, or a direct hydrogenation of a fatty acid. In the case of the oxo method, a linear product and a branched product are produced, but they can be separated and purified into single products by precision distillation. Specific examples of the alkyl aldehyde are as follows, but are not necessarily limited thereto.

For example, examples of linear alkyl aldehydes include valeraldehyde, caproaldehyde, heptanal, octanal, decylaldehyde, dodecanal, tetradecanal, octadecanal, beheninaldehyde and the like.

As α-branched alkyl aldehydes, isobutyl aldehyde, 2-methyl butyraldehyde, 2-methyl pentanal, 2-ethyl butanal, 2-methyl hexanal, 2-ethyl pentanal, 2-methyl heptanal, 2-ethyl hexanal, 2-propylpentanal and the like.

As the α-branched alkyl group in which one or more branches are present in addition to the α-branch in the α-branch, 2,3-dimethylbutanal, 2,4,4-trimethylpentanal,
2-isopropyl-5-methylhexanal and the like.

Other branched alkyl aldehydes having one or more branches other than the α-branch include isovaleraldehyde, 3-methylpentanal, 4-methylpentanal, 3,3-dimethylbutanal, Examples include methylhexanal, 4-methylhexanal, 5-methylhexanal, 3,5,5-trimethylhexanal, isodecylaldehyde, 3,7-dimethyloctanal, isooctadecanal and the like.

The reactive derivative of the carbonyl compound used in the second invention includes the above-mentioned ketone, aldehyde and lower alcohol having 1 to 6 carbon atoms represented by the general formula (iv ') which is easily synthesized by an acid catalyst. With the indicated ketal,
There is acetal. Specific examples of lower alcohols having 1 to 6 carbon atoms that provide the R ⁷ residue include methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, tert-butanol,
Amyl alcohol, isoamyl alcohol, neopentyl alcohol, 1-methylbutanol, 1,1-dimethylpropanol, 1-ethylpropanol, hexanol, isohexanol, 2-ethylbutanol, 1-methylamyl alcohol, 1,3-dimethylbutanol, 1
-Ethyl butanol and the like.

In the second invention, the reaction between the hexahydric alcohol represented by the formula (iii) and the ketone is a ketalization reaction, and the molar ratio of the ketone to the hexahydric alcohol represented by the formula (iii) is 1.5 to 15, preferably 2.7 to 7.5. This reaction is performed using an acid catalyst such as paratoluenesulfonic acid, methanesulfonic acid, sulfuric acid or the like as a catalyst in an amount of 0.1 to 10 mol%, preferably 1.0 to 5 mol%, based on the hexahydric alcohol represented by the formula (iii). .

This reaction is carried out without solvent or xylene, toluene, benzene, octane, isooctane, heptane, hexane,
In an inert solvent such as cyclohexane, pentane, ligroin, petroleum ether or a mixed solvent thereof, 30 to 130 ° C., preferably 6 to 130 ° C., depending on the boiling point of the ketone used.
It is preferable to carry out at a temperature of 0 to 100 ° C. while removing generated water. If the temperature is in these ranges, the reaction proceeds favorably, and coloring due to side reactions tends to be small. Further, under nitrogen flow conditions, any of a nitrogen atmosphere and a dry air atmosphere may be used. The reaction time can vary depending on various conditions, but is usually preferably 5 to 200 hours. The obtained cyclic ketal (i) or (ii) is neutralized and filtered.
After pretreatment such as washing, purification can be performed by operations such as adsorption treatment, crystallization, and distillation.

The reaction between the hexahydric alcohol represented by the formula (iii) and the aldehyde is an acetalization reaction, and the molar ratio of the aldehyde to the hexahydric alcohol represented by the formula (iii) is
It is 1.5-6, preferably 2.7-3.8. This reaction is carried out using an acid catalyst such as paratoluenesulfonic acid, methanesulfonic acid or sulfuric acid as a catalyst in an amount of 0.01 to 5 mol%, preferably 0.1 to 2 mol%, based on the hexahydric alcohol represented by the formula (iii).

This reaction is carried out without solvent or xylene, toluene, benzene, octane, isooctane, heptane, hexane,
In an inert solvent such as cyclohexane, pentane, butane, ligroin, petroleum ether or a mixture thereof, depending on the boiling point of the aldehyde used, 20 to 130 ° C.
It is preferably carried out at a temperature of 40 to 100 ° C. while removing water generated. If the temperature is in these ranges,
This is because the reaction proceeds favorably, and coloring due to side reactions tends to be small. Further, under a nitrogen flow condition, any of a nitrogen atmosphere and a dry air atmosphere may be used. The reaction time is
Although it may vary depending on various conditions, it is usually preferable to be 1 to 30 hours. The obtained cyclic acetal (i) or (ii) can be neutralized, subjected to pretreatment such as filtration and washing, and then purified by operations such as adsorption treatment, crystallization, and distillation.

The reaction between the hexahydric alcohol represented by the formula (iii) and the ketal (iv '), which is a reactive derivative of a ketone, is a transketalization reaction, and the reaction represented by the formula (iii)
The molar ratio of ketal (iv ') to polyhydric alcohol is 1.5
-15, preferably 2.7-7.5. This reaction is carried out using an acid catalyst such as paratoluenesulfonic acid, methanesulfonic acid, sulfuric acid or the like as a catalyst in an amount of 0.1 to 10 mol%, preferably 1.0 to 5 mol%, based on the hexahydric alcohol represented by the formula (iii).

This reaction is carried out without solvent or xylene, toluene, benzene, octane, isooctane, heptane, hexane,
In an inert solvent such as cyclohexane, pentane, ligroin, petroleum ether or a mixed solvent thereof, it depends on the boiling point of the ketal (iv ') and the lower alcohol to be formed, but is preferably 40 to 150 ° C, preferably 70 to 130 ° C. It is preferable to carry out the reaction while removing the lower alcohol formed at a temperature of ° C. If the temperature is in these ranges, the reaction proceeds favorably, and coloring due to side reactions tends to be small. Further, under nitrogen flow conditions, any of a nitrogen atmosphere and a dry air atmosphere may be used. The reaction time may vary depending on various conditions, but is usually preferably 5 to 200 hours. The obtained cyclic ketal (i) or (ii) can be purified by operations such as adsorption treatment, crystallization and distillation after neutralization, pretreatment such as filtration and washing.

Further, the reaction between the hexahydric alcohol represented by the formula (iii) and the acetal (iv ') which is a reactive derivative of the aldehyde is a transacetalization reaction, and the acetal to the hexahydric alcohol represented by the formula (iii) ( The molar ratio of iv ') is from 1.5 to 6, preferably from 2.7 to 3.8. This reaction is carried out using an acid catalyst such as paratoluenesulfonic acid, methanesulfonic acid or sulfuric acid as a catalyst in an amount of 0.01 to 5 mol%, preferably 0.1 to 2 mol%, based on the hexahydric alcohol represented by the formula (iii).

This reaction is carried out without solvent or xylene, toluene, benzene, octane, isooctane, heptane, hexane,
In an inert solvent such as cyclohexane, pentane, butane, ligroin, petroleum ether or a mixed solvent thereof, it depends on the acetal (iv ') used and the boiling point of the lower alcohol to be produced, but is preferably from 20 to 150C, preferably from 50 to 150C. 130
It is preferable to carry out the reaction while removing the lower alcohol formed at a temperature of ° C. If the temperature is in these ranges, the reaction proceeds favorably, and coloring due to side reactions tends to be small. Further, under a nitrogen flow condition, any of a nitrogen atmosphere and a dry air atmosphere may be used. The reaction time may vary depending on various conditions, but is usually preferably 1 to 30 hours.
The obtained cyclic acetal (i) or (ii) can be neutralized, subjected to pretreatment such as filtration and washing, and then purified by operations such as adsorption treatment, crystallization, and distillation.

In the production method of the second invention, as described above, when an aldehyde is used, a mixture of the general formulas (i) and (ii) can be obtained. The separation may be performed according to the means for separating and purifying the compound, for example, precision distillation, column chromatography, thin-layer chromatography, fractional crystallization, preparative HPLC (liquid chromatography), isolation by preparative gas chromatography, or the like. However, since both have similar physical properties, they can be used as synthetic lubricating oil, refrigerating machine oil, etc. without separating them.

According to the production method of the second invention, the aforementioned cyclic acetal can be obtained in a high yield by a simple method.

Hereinafter, Production Examples, Examples, Synthesis Examples, and Test Examples of the present invention will be described, but the present invention is not limited thereto. The production examples and examples relate to the first invention, and the synthesis examples and test examples relate to the second invention.

Production Example 1 A 3-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen blowing tube, and a dehydrating tube equipped with a condenser. D
-336.8 g (1.85 mol) of sorbitol, 800.0 g (11.1 mol) of methyl ethyl ketone, 17.6 g (0.092 mol) of paratoluenesulfonic acid monohydrate, and 200 ml of hexane were placed in the flask at atmospheric pressure under a nitrogen atmosphere. The reaction was carried out at 79 ° C. for 8 hours, and water was distilled off. After completion of the reaction, the mixture was cooled to 60 ° C., neutralized by adding 19.6 g (0.185 mol, twice equivalent of paratoluenesulfonic acid) of sodium carbonate, and stirred at 60 ° C. for 30 minutes.
200 g of water was added, and the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand, and separated. After removing the lower layer, the residue was washed with 200 g of saturated saline, and hexane and excess methyl ethyl ketone were removed under reduced pressure using a rotary evaporator. Further, distillation under reduced pressure was performed to obtain a cyclic ketal A ₁ (hydroxyl value 12.9 mgKOH / g, gas chromatography purity 97.3%). Then, further purified part of a cyclic ketal A ₁ by column chromatography to give a cyclic ketal A ₂ (hydroxyl value 0.0mgKOH / g, the gas chromatographic purity 99.8%).

Production Example 2 A 3-liter four-necked flask was equipped with a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube equipped with a condenser.
D-sorbitol 450.0 g (2.47 mol), isobutyraldehyde 588.0 g (8.15 mol), paratoluenesulfonic acid 1
4.7 g (0.025 mol) of hydrate and 400 mol of petroleum ether having a boiling point of 30 to 60 ° C. were placed in the flask. The reaction was carried out at 40 to 65 ° C. for 15 hours under normal pressure in a dry air atmosphere, and water was distilled off. After the completion of the reaction, the mixture was cooled to 60 ° C., and 5.24 g of sodium carbonate (0.049 g) was added.
mol, twice the equivalent of paratoluenesulfonic acid) and neutralized, and stirred at 60 ° C. for 30 minutes. Add 100g of water and at 60 ° C
The mixture was stirred for 30 minutes, allowed to stand, and separated. After removing the lower layer, the residue was washed with 100 g of saturated saline, petroleum ether and excess isobutyraldehyde were removed under reduced pressure using a rotary evaporator, and further distilled under reduced pressure to obtain cyclic acetal B.
(Hydroxyl value 6.0mgKOH / g, gas chromatography purity 99.
0%).

Production Example 3 A 3-liter four-necked flask was equipped with a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube with a condenser.
D-sorbitol 450.0 g (2.47 mol), n-butyraldehyde 588.0 g (8.15 mol), p-toluenesulfonic acid 1
4.7 g (0.025 mol) of hydrate and 400 mol of hexane were placed in the flask. 5 at 62-83 ° C under normal pressure in dry air atmosphere
The reaction was carried out for an hour and distilled off with water. After completion of the reaction, the mixture was cooled to 60 ° C, neutralized by adding 5.24 g (0.049 mol, twice equivalent of paratoluenesulfonic acid) of sodium carbonate, and stirred at 60 ° C for 30 minutes. 100 g of water was added, and the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand, and separated. After removing the lower layer, it was washed with 100 g of saturated saline,
Hexane and excess n-butyraldehyde were removed under reduced pressure using a rotary evaporator, followed by distillation under reduced pressure to obtain cyclic acetal C ₁ (hydroxyl value 13.1 mgKOH / g, purity 97.8% by gas chromatography). Then, further portions of cyclic acetals C ₁ was purified by column chromatography, cyclic acetal C ₂ (hydroxyl value 4.1MgKOH /
g, gas chromatography purity 99.3%).

Production Example 4 A 3-liter four-necked flask was equipped with a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube equipped with a condenser.
D-sorbitol 363.8 g (2.00 mol), methyl isobutyl ketone 1200 g (12.0 mol), paratoluenesulfonic acid 1
18.99 g (0.100 mol) of hydrate and 300 ml of hexane were placed in the flask. 93 ~ 98 ℃ at normal pressure under dry air atmosphere
The reaction was carried out for 23 hours, and water was distilled off. After completion of the reaction, the mixture was cooled to 60 ° C., neutralized by adding 21.16 g (0.200 mol, twice equivalent of paratoluenesulfonic acid) of sodium carbonate, and stirred at 60 ° C. for 30 minutes. 200 g of water was added, and the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand, and separated. After removing the lower layer, the residue was washed with 200 g of a saturated saline solution, hexane and excess methyl isobutyl ketone were removed under reduced pressure using a rotary evaporator, and low-boiling components were further removed by distillation under reduced pressure. 657.6 g of the obtained crude ketal was filtered through activated clay to obtain a cyclic ketal.
D ₁ (hydroxyl value 34.3mgKOH / g, gas chromatography purity
93.1%). Further, a part of the cyclic ketal D ₁ was purified by column chromatography, and the cyclic ketal D ₁ was purified.
₂ (hydroxyl value 0.0mgKOH / g, gas chromatography purity 9
9.6%).

Production Example 5 A 3-liter four-necked flask was equipped with a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube with a condenser.
D-sorbitol 170.8 g (0.937 mol), 3,5,5-trimethylhexanal 400.0 g (2.81 mol), paratoluenesulfonic acid monohydrate 1.78 g (0.0094 mol), and hexane 40
0 ml was placed in the flask. 7 at normal pressure under dry air atmosphere
The reaction was carried out at 9 to 81 ° C for 8 hours, and water was distilled off. After the completion of the reaction, the mixture was cooled to 70 ° C., and 1.99 g of sodium carbonate (0.019 mol,
(2 equivalents of p-toluenesulfonic acid) to neutralize,
Stirred at 70 ° C. for 30 minutes. 100 g of water was added, and the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand, and separated. After removing the lower layer, saturated saline
After washing with 100 g, hexane was removed under reduced pressure using a rotary evaporator, and low-boiling components were further removed by distillation under reduced pressure. Hexane 50 in 500.9 g of the obtained crude acetal
After 0 ml was added and the mixture was filtered through activated clay, hexane was removed under reduced pressure using a rotary evaporator to obtain cyclic acetal E (hydroxyl value 27.2 mgKOH / g, gas chromatography purity 93.2%).

Production Example 6 A 1-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen blowing tube, and a dehydrating tube with a condenser. 166.0 g (1.00 mol) of diglycerin, methyl ethyl ketone 28
8.0 g (4.00 mol), paratoluenesulfonic acid monohydrate 3.8
0 g (0.020 mol) and 100 ml of hexane were placed in the flask. The reaction was carried out at 66-81 ° C. for 15 hours under normal pressure under a nitrogen atmosphere, and water was distilled off. After the completion of the reaction, the mixture was cooled to 60 ° C., and 4.24 g of sodium carbonate (0.040 mol, 2 parts of paratoluenesulfonic acid)
And the mixture was neutralized by stirring at 60 ° C. for 30 minutes. Water 10
After adding 0 g, the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand, and separated. After removing the lower layer, the mixture was washed with 100 g of water, hexane and excess methyl ethyl ketone were removed under reduced pressure using a rotary evaporator, and low-boiling components were further removed by distillation under reduced pressure. To 223.0 g of the obtained crude ketal, activated alumina 0.6 g
Was added and stirred at 50 ° C. for 30 minutes. After filtration, cyclic ketal F ₁ (hydroxyl value 15.7 mgKOH / g, gas chromatography purity 96.7%) was obtained. And further, cyclic ketals
A part of F ₁ was purified by column chromatography,
The cyclic ketal F ₂ (hydroxyl value 0.0 mgKOH / g, gas chromatography purity 99.7%) was obtained.

Production Example 7 A 1-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen blowing tube, and a dehydrating tube equipped with a condenser. 100.0 g (0.602 mol) of glycerin, 180.8 g (1.81 mol) of methyl isobutyl ketone, 2.29 g (0.012 mol) of paratoluenesulfonic acid monohydrate, and 300 ml of toluene were placed in the flask. The reaction was carried out at 110 to 119 ° C. for 55 hours under normal pressure under a nitrogen atmosphere, and water was distilled off. After completion of the reaction, the mixture was cooled to 60 ° C., neutralized by adding 2.54 g (0.024 mol) of sodium carbonate and twice equivalent of paratoluenesulfonic acid), and stirred at 60 ° C. for 30 minutes. 100 g of water was added, and the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand, and separated. After removing the lower layer, the residue was washed with 50 g of saturated saline, toluene and excess methyl isobutyl ketone were removed under reduced pressure using a rotary evaporator, and further, distillation under reduced pressure was performed to obtain a cyclic ketal G ₁ (hydroxyl value 26.2 mgKOH / g, Gas chromatography purity 95.1%). Then, further purified part of a cyclic ketal G ₁ by column chromatography to give a cyclic ketal G ₂ (hydroxyl value 1.6 mg KOH / g, the gas chromatographic purity of 99.5%).

Production Example 8 A 3-liter four-necked flask was equipped with a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube equipped with a condenser.
332.4 g (2.00 mol) of diglycerin, diisobutyl ketone 8
53.4 g (6.00 mol), paratoluenesulfonic acid monohydrate 7.
61 g (0.040 mol) and 500 ml of hexane were placed in the flask. The reaction was carried out at a normal pressure of 96 to 97 ° C for 123 hours under a stream of dry air to distill off water. After completion of the reaction, the mixture was cooled to 60 ° C., neutralized by adding 8.48 g (0.080 mol, twice equivalent of paratoluenesulfonic acid) of anthorium carbonate, and stirred at 60 ° C. for 30 minutes. 100 g of water was added, and the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand, and separated. After removing the lower layer, the mixture was washed with 100 g of saturated saline, hexane was removed under reduced pressure using a rotary evaporator, and diisobutyl ketone was removed by distillation under reduced pressure. To 666.7 g of the obtained crude ketal, 400 ml of hexane
After filtration through activated clay, hexane was removed under reduced pressure using a rotary evaporator to obtain cyclic ketal H (hydroxyl value 4.0 mgKOH / g, gas chromatography purity 98.0%).

Production Example 9 A 1-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen blowing tube, and a dehydrating tube with a condenser. 166.0 g (1.00 mol) of glycerin, 289.7 g (2.04 mol) of 3,5,5-trimethylhexanal, 1.90 g (0.010 mol) of paratoluenesulfonic acid monohydrate, and 150 mol of hexane were placed in the flask. The reaction was carried out at 75 to 92 ° C. for 8 hours under a nitrogen stream at normal pressure to distill off water. After completion of the reaction, the mixture was cooled to 60 ° C, neutralized by adding 2.12 g (0.020 mol, twice equivalent of paratoluenesulfonic acid) of sodium carbonate, and stirred at 60 ° C for 30 minutes. 100 g of water was added, and the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand, and separated. After removing the lower layer, it was washed with 100 g of saturated saline,
Hexane was removed under reduced pressure using a rotary evaporator, and low-boiling components were further removed by distillation under reduced pressure. 1.2 g of activated alumina was added to 405.5 g of the obtained crude acetal, followed by stirring at 50 ° C. for 30 minutes. After filtration, cyclic acetal I ₁ (hydroxyl value 23.1 mg KOH / g, gas chromatography purity 94.3%) was obtained. And further cyclic acetal
A part of I ₁ was purified by column chromatography,
The cyclic acetal I ₂ (hydroxyl value 2.7 mgKOH / g, gas chromatography purity 99.1%) was obtained.

Production Example 10 A 1-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen blowing tube, and a dehydrating tube with a condenser. Diglycerin 100.0 g (0.602 mol), 6-undecanone 205.
0 g (1.20 mol), 2.29 g of paratoluenesulfonic acid monohydrate
(0.012 mol) and 300 ml of toluene were placed in the flask. The reaction was carried out at a normal pressure of 122 to 124 ° C. for 48 hours under a nitrogen stream to remove water. After completion of the reaction, the mixture was cooled to 60 ° C, neutralized by adding 2.54 g (0.024 mol, twice equivalent of paratoluenesulfonic acid) of sodium carbonate, and stirred at 60 ° C for 30 minutes. 100g of water
Was added, and the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand still, and separated. After removing the lower layer, the residue was washed with 50 g of saturated saline, toluene was removed under reduced pressure using a rotary evaporator, and distillation under reduced pressure was performed to obtain a cyclic ketal J ₁ (having a hydroxyl value of 13.2 mg KO).
H / g, gas chromatography purity 96.5%). Then, a part of the cyclic ketal J ₁ is further purified by column chromatography to obtain a cyclic ketal J ₂ (having a hydroxyl value of 0.9 m).
gKOH / g, gas chromatography purity 99.9%).

Production Example 11 A 1-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen blowing tube, and a dehydrating tube equipped with a condenser. me
so-erythritol 122.0 g (1.00 mol), methyl ethyl ketone 288.0 g (4.00 mol), paratoluenesulfonic acid 1
3.80 g (0.020 mol) of hydrate and 100 ml of hexane were placed in the flask. The reaction was carried out at 63 to 78 ° C under normal pressure for 15 hours under a nitrogen atmosphere, and water was distilled off. After completion of the reaction, the reaction mixture was cooled to 60 ° C, neutralized by adding 4.24 g (0.040 mol, twice equivalent of paratoluenesulfonic acid) of sodium carbonate, and stirred at 60 ° C for 30 minutes. 100 g of water was added, and the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand, and separated. After removing the lower layer, the residue was washed with 100 g of water, hexane and excess methyl ethyl ketone were removed under reduced pressure using a rotary evaporator, and further distilled under reduced pressure to obtain a cyclic ketal K (hydroxyl value 1.0 mg KOH / g, gas chromatography). Purity 99.4%).

Production Example 12 A three-liter four-necked flask was equipped with a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube equipped with a condenser.
270.0 g (2.21 mol) of meso-erythritol, 629.0 g (4.42 mol) of 3,5,5-trimethylhexanal, 4.21 g (0.022 mol) of paratoluenesulfonic acid monohydrate, and hexane 6
00 ml was placed in the flask. At normal pressure under dry air atmosphere
The reaction was carried out at 76 to 83 ° C for 7 hours, and water was distilled off. After the completion of the reaction, the mixture was cooled to 60 ° C., and 4.68 g of sodium carbonate (0.044 mol,
(2 equivalents of p-toluenesulfonic acid) to neutralize,
Stirred at 60 ° C. for 30 minutes. 100 g of water was added, and the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand, and separated. After removing the lower layer, saturated saline
After washing with 100 g, hexane was removed under reduced pressure using a rotary evaporator, and low-boiling components were further removed by distillation under reduced pressure. Hexane 40 was added to 781.8 g of the obtained crude acetal.
After 0 ml was added and the mixture was filtered through activated clay, hexane was removed under reduced pressure using a rotary evaporator to obtain cyclic acetal L ₁ (hydroxyl value 20.2 mgKOH / g, gas chromatography purity 95.3%). Then, a part of the cyclic acetal L ₁ is further purified by column chromatography, and the cyclic acetal L ₂ (having a hydroxyl value of 5.1 mgKOH / g,
(Gas chromatography purity 98.0%).

Production Example 13 A 3-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen blowing tube, and a dehydrating tube equipped with a condenser. D
-336.8 g (1.85 mol) of mannitol, 800.0 g (11.1 mol) of methyl ethyl ketone, paratoluenesulfonic acid monohydrate 1
7.6 g (0.092 mol) and 200 ml of hexane were placed in the flask. The reaction was carried out at 68-76 ° C. for 10 hours under a nitrogen atmosphere at normal pressure, and water was distilled off. After completion of the reaction, the mixture was cooled to 60 ° C., neutralized by adding 19.6 g (0.185 mol, twice equivalent of paratoluenesulfonic acid) of sodium carbonate, and stirred at 60 ° C. for 30 minutes. water
200 g was added, and the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand, and separated.
After removing the lower layer, the residue was washed with 200 g of saturated saline, and hexane and excess methyl ethyl ketone were removed under reduced pressure using a rotary evaporator. Further, distillation under reduced pressure, purification by column chromatography, and cyclic ketal M
(Hydroxyl value 0.2mgKOH / g, gas chromatography purity 99.
6%).

Production Example 14 A 3-liter four-necked flask was equipped with a stirrer, a thermometer, and a dehydrating tube equipped with a condenser. 500 g (3.73 mol) of trimethylolpropane, 777 g of 2,2-dimethoxypropane
(7.46 mol), and paratoluenesulfonic acid monohydrate 14.
17 g (0.075 mol) was placed in the flask. The reaction was carried out under a nitrogen atmosphere at normal pressure at 60 to 70 ° C. for 2 hours, and methanol was distilled off. After completion of the reaction, the same post-treatment as in Production Example 13 was performed, and further, distillation under reduced pressure was performed to give 1,3-dioxa-5-ethyl-
2,2-dimethyl-5-cyclohexyl-methanol (N
a) 584.9 g (yield 90%, hydroxyl value 322.6 mg KOH /
g).

A 2-liter four-necked flask was equipped with a stirrer, a thermometer, a cooler, and a dropping funnel, and was purged with nitrogen. 20.0 g (0.5 mol) of sodium hydride (60% content, oily), 450 ml of 1,2-dimethoxyethane, and 150 ml of dimethyl sulfoxide were placed in the flask. Under a nitrogen atmosphere, 87.1 g (0.5 mol) of the compound (Na) obtained above was added dropwise at room temperature over 15 minutes, and the mixture was further stirred for 1 hour, and subsequently, ethylene glycol di-p-tosylate (Tokyo Kasei ( Co., Ltd.) Powder 7
7.0 g (0.208 mol) was added over 30 minutes. After stirring at 70 ° C. under a nitrogen atmosphere overnight, water (750 ml) and diethyl ether (500 ml) were added and the layers were separated.
Extracted twice with 00 ml. The combined organic layers were washed three times with 300 ml of a 5% aqueous sodium carbonate solution, and dried over a mixture of anhydrous sodium sulfate and anhydrous sodium carbonate. The solvent was removed with a rotary evaporator to obtain 115.3 g of an oily substance. This was further purified by silica gel column chromatography (developing solvent with hexane / ethyl acetate), and ethylene glycol di- [1,3-dioxa-5-ethyl-2,2-dimethyl-5-cyclohexyl] methyl ether (Nb) was used. 51
g was obtained (purity of column chromatography: 99%, hydroxyl value: 0.0 mg KOH / g).

A 1 liter four-necked flask was equipped with a stirrer, thermometer, and condenser. 50 g of the compound (Nb) obtained above
(0.13 mol), 500 ml of ethanol and 50 ml of 1N hydrochloric acid were placed in the flask. The reaction was carried out at 80 to 100 ° C. under reflux in a nitrogen atmosphere for 5 hours, cooled to room temperature, and neutralized with 1N sodium hydroxide. The solution obtained by completely distilling off the solvent under reduced pressure was dissolved in water, and after electrodialysis, water was removed, and 2,9-diethyl-2,9-dihydroxymethyl-4,7.
-Dioxadecane-1,10-diol (Nc) 37.6 g was obtained.

A 300 ml four-necked flask was equipped with a dehydrating tube equipped with a stirrer, thermometer, and condenser. 37 g (0.13 mol) of the compound (Nc) obtained above and 28.1 g (0.3
9 mol), 0.49 g (0.002 g) of paratoluenesulfonic acid monohydrate
6 mol) and 50 g of hexane were placed in the flask. The reaction was carried out at 60 to 70 ° C. for 8 hours under normal pressure under a nitrogen atmosphere, and water was distilled off. After completion of the reaction, the same post-treatment as in Production Example 13 was performed, and the solvent was removed with a rotary evaporator to obtain 52.3 g of an oily substance. This was further purified by silica gel column chromatography (hexane / ethyl acetate as a developing solvent),
45 g of ethylene glycol di- [1,3-dioxa-2,5-diethyl-2-methyl-5-cyclohexyl] methyl ether (cyclic ketal N) were obtained (column chromatography purity 98.5%; hydroxyl value 0.0 mg KOH / g). ).

Production Example 15 Trimethylolpropane 292.
1 g (2.18 mol), 474.0 g (8.17 mol) of acetone, 6.0 g (0.0315 mol) of paratoluenesulfonic acid monohydrate, and 900 ml of hexane were added, and the mixture was refluxed for 24 hours to remove generated water out of the system. After neutralizing the reaction product with aqueous sodium hydroxide,
By distilling under reduced pressure, 5-hydroxymethyl-5-
Ethyl-2,2-dimethyl-1,3-dioxane was synthesized.

Next, a 500 ml stainless steel autoclave (stirrer,
A liquid introduction tube, a gas discharge tube, and a thermometer) were used, and the above-mentioned 5-hydroxymethyl-5-ethyl-2,2-dimethyl-1,3-dioxane 17.4 g (0.1 mol), 28% by weight sodium methylate methanol solution was added. 0.19 g (0.001 mol) and 5 ml of toluene were added, and the pressure was gradually reduced from normal pressure (0.4 mm
Hg), and the low boiling components were removed from the gas discharge pipe. After sealing
58.0 g of propylene oxide (1.0 m
ol) was pressed into the autoclave over 8 hours. After cooling, the reaction mixture was added with 21.2 g (0.11 mol) of a methanol solution of 28% by weight sodium methylate and 150 ml of toluene, and heated at 110 ° C.
Reduce the pressure gradually from normal pressure over 2 hours under heating (0.4mmHg)
And the low boiling components were distilled off from the gas discharge tube.

After cooling, 15.6 g (0.11 mol) of methyl iodide was added and the mixture was sealed and heated at 60 ° C. for 3 hours and further at 90 ° C. for 5 hours. After cooling, 2.8 g of Kyoward 600 (alkali adsorbent, manufactured by Kyowa Chemical Industry Co., Ltd.) was added, and the mixture was stirred for 1 hour, followed by filtration to obtain oil fa to be used as a comparative product (gas chromatography purity: 78%). . Further, a part of fa was purified by column chromatography to obtain an oil f (purity of gas chromatography: 85%) used as a comparative product.

Example 1 Hydroxyl value (JIS K-0070) of cyclic ketal and cyclic acetal A _{1 to} N used in the product of the present invention obtained in Production Example and unreacted hydroxyl group based on the number of hydroxyl groups of raw material polyhydric alcohol obtained from this hydroxyl value , Kinematic viscosity at 40 ° C and 100 ° C (JIS K-2283), and pour point (JIS K-2269) were measured. Table 1 shows the results. Also, the oil a used for the comparative product
Kinematic viscosity (JIS K-2283) at 40 ° C and 100 ° C for
The pour point (JIS K-2269) was measured. Table 2 shows the results.

Example 2 Cyclic ketal and cyclic acetal A _{1 to} D ₂ , F _{1 to} I ₂ , K, M, N and 1,1,1,2-
Tetrafluoroethane (HFC134a) or a mixed refrigerant of 1,1,1,2-tetrafluoroethane and difluoromethane (HFC32) or 1,1,1,2-tetrafluoroethane, difluoromethane and pentafluoroethane (HFC125) The compatibility of the mixed refrigerant with was investigated.

The cyclic ketals and cyclic acetals A _{1 to} D ₂ shown in Table 3
F _{1 to} I ₂ , K, M, N and 1,1,1,2-tetrafluoroethane (HFC134a) or a mixed refrigerant of 1,1,1,, 2-tetrafluoroethane and difluoromethane (HFC32) or 1 , 1,
The oils a (naphthenic oils) used for the present invention products 1 to 20 and comparative products, which are compositions of a mixed refrigerant of 1,2-tetrafluoroethane, difluoromethane and pentafluoroethane (HFC125), and 1,1,1, The low-temperature two-phase separation temperature of Comparative Product 1, which was a composition with 2-tetrafluoroethane, was measured. Table 3 shows the results.

As is clear from Table 3, the product of the present invention is excellent in compatibility with hydrofluorocarbons at low temperatures. Among the products of the present invention, cyclic ketals and cyclic acetals A ₁ , A ₂ , B,
_{D 1, D 2, F 1} , F 2, G 2, K, composition of M is particularly excellent.
In addition, cyclic ketals A ₁ and A ₂ (products of the present invention 1 and 2), D ₁ and D ₂
(Products 6 and 7 of the present invention), cyclic acetal I ₁ and I ₂ (Products of the present invention
As can be seen by comparing 11 and 17), the smaller the unreacted hydroxyl group, the better the compatibility with the hydrofluorocarbon.

A cyclic ketal A ₂ used in the present invention product obtained in Example 3 Preparation
The compatibility of the present invention product 2, which is a composition of 1,1,1,2-tetrafluoroethane (HFC134a), at a high temperature was examined. Inner volume 372c
Ring ketal A _{2 in} autoclave with m ^{2 view} port
60.0 g and 240.0 g of HFC134a were taken, and the mixture was heated from room temperature to 100 ° C. with appropriate stirring, and the separated state of the mixed solution was visually inspected.

The product 2 of the present invention (oil concentration: 20% by weight) was uniformly dissolved from room temperature to 100 ° C., and no separated state was observed. Similarly, 20.0 g of cyclic ketal A ₂ and 380.0 g of HFC134a were taken, and the separation state was examined. The product 2 of the present invention (oil concentration 5% by weight) was uniformly dissolved from room temperature to 100 ° C., and the separation state was observed. Was not done.

Similarly, the product 2 of the present invention having an oil concentration of 10% by weight, 30% by weight, 40% by weight, and 50% by weight was more uniformly dissolved at room temperature than 100 ° C., and no separation state was observed.

Example 4 Cyclic ketal A ₁ used in the product of the present invention obtained in Production Example,
A ₂ , B, C ₂ , D ₁ , D ₂ , F ₂ , I ₂ , J ₂ , K, L ₂ , M, N and oil b (polyalkylene glycol) used for comparison products and the electrical insulation of f Examined. Also investigated the electric insulation Similarly, the mixture of oils b used in comparative with cyclic ketal A ₂ (50:50 weight ratio).

The volume resistivity at 25 ° C. was measured based on JIS C-2101. Table 4 shows the results.

As is clear from Table 4, the product of the present invention had a high volume resistivity, and had better electric insulation than Comparative Examples b and f. Further, by mixing the cyclic ketal or cyclic acetal used in the product of the present invention with the polyalkylene glycol, the electrical insulation of the polyalkylene glycol can be improved. Moreover, as can be seen when comparing the cyclic ketal A ₁ and A _2, D ₁ and D _2, has good electrical insulating properties as unreacted hydroxyl groups is small. Moreover, cyclic ketal A ₂ and cyclic acetal B, as can be seen when comparing the C _2, cyclic ketal A ₂ obtained from ketone, cyclic acetal B obtained from aldehydes, are good electrical insulating properties than C _2. NMR analysis and gas chromatography analysis, cyclic ketal A ₂ are all III a structure, cyclic acetal B, C
Has a IIIa structure / IIIb structure ratio of 56/44 and 34/66, respectively. Therefore, the more the compound has a 1,3-dioxolane structure, the better the electrical insulation. On the other hand, the cyclic ketal N having two ether bonds in the polyhydric alcohol moiety has a higher electrical insulation property than the cyclic ketal or the cyclic acetal A to M having one ether bond or no ether bond in the polyhydric alcohol moiety. Inferior.

Example 5 cyclic ketal or cyclic acetal A ₁ used in the present invention product obtained in Production _{Example, A 2, B, D 2} , F 1, G 2, K, M and 1,1,1,
2-tetrafluoroethane (HFC134a) or 1,1,1,
The product 1, 2, 3, 4 of the present invention which is a mixed refrigerant of 2-tetrafluoroethane and difluoromethane or a mixed refrigerant of 1,1,1,2-tetrafluoroethane, difluoromethane and pentafluoroethane , 7, 8, 12, 16, 1
For tubes 8 and 19, a shield tube test was performed under the following conditions to examine thermal stability.

That is, a water concentration of 10 ppm or less and an acid value of 0.03 (m
gKOH / g) Take 10 g of lubricating oil prepared below and 5 g of hydrofluorocarbon in a glass tube, and use iron, copper,
Aluminum was added and the tube was sealed. After a test at 175 ° C. for 14 days, the appearance of the composition of hydrofluorocarbon and oil and the presence or absence of precipitates were examined. The sealed tube was opened to remove the hydrofluorocarbon, and then the acid value of the oil was examined. Table 5 shows the results.

As is clear from Table 5, all of the products of the present invention have good appearance, no precipitate, and no increase in acid value.
Thermal stability was good.

Example 6 Cyclic ketal and cyclic acetal A ₁ , A ₂ , B, D ₂ , F ₁ , G ₂ , K, M, and 1,1,1, used in the product of the present invention obtained in Production Example
2-tetrafluoroethane (HFC134a) or 1,1,1,2
A product of the present invention 1, 2, 3, 4, which is a composition of a mixed refrigerant of tetrafluoroethane and difluoromethane, or a mixed refrigerant of 1,1,1,2-tetrafluoroethane, difluoromethane and pentafluoroethane. 7, 8, 12, 16, 1
Oils c and d (ester) used for 8, 19 and comparative products
About the comparative products 2 and 3, which are compositions with 1,2-tetrafluoroethane (HFC134a), a shield tube test was performed under the following conditions in order to examine thermal stability in the presence of water. Mixtures of c for use in comparative and cyclic ketal A ₁ (50:50 weight ratio) and 1,1,1,2-tetrafluoroethane (HF
The same test was carried out for the product 21 of the present invention which is a composition with C134a).

That is, a water concentration of 3000 ppm and an acid value of 0.03 (mgK
OH / g) 10 g of the lubricating oil prepared below and 5 g of nominal hydrofluorocarbon were placed in a glass tube, and iron, copper, and aluminum were added as a catalyst and the tube was sealed. After a test at 175 ° C. for 14 days, the appearance of the composition of hydrofluorocarbon and oil and the presence or absence of precipitates were examined. The sealed tube was opened to remove the hydrofluorocarbon, and then the acid value of the oil was examined. Table 6 shows the results.

As is clear from Table 6, all of the products of the present invention have good appearance, no precipitates, and no increase in oxidation.
The thermal stability in the presence of water was good. Also, the product of the present invention
As shown in 21, the hydrolysis of the ester was prevented by adding the cyclic ketal and the cyclic acetal of the present invention to the ester.

Example 7 cyclic ketal or cyclic acetal A ₁ used in the present invention product obtained in Production Example, B and a 1,1,1,2 composition of tetrafluoroethane (HFC134a) Invention Product 1 and 4 For the comparative products 3 and 4, which are compositions of oils d and e (esters) and 1,1,1,2-tetrafluoroethane (HFC134a) used for the comparative products, the abrasion resistance was determined by the Falex test. I checked.

100 ml of oil is heated to 80 ° C., and 1,1,1,2-tetrafluoroethane (HFC134a) is blown at a rate of 10 liters per hour, and 150 (lb)
The operation was carried out for 4 hours under the load described above, and the wear amount of the V block and the pin after the operation was examined. Table 7 shows the results.

As is clear from Table 7, the products of the present invention all have a small amount of abrasion and are excellent in abrasion resistance.

Oil b used in comparative with cyclic ketal A ₂ used in the present invention product obtained in Example 8 Preparation (polyalkylene glycol), c
(Ester) was examined for hygroscopicity.

In a glass tube with an inner diameter of 18 mm and an internal volume of about 10 ml,
2 g of oil adjusted to 50 ppm or less was taken and placed in a thermostat at 25 ° C. and 80% humidity. After standing for a certain time, the water concentration of the oil was measured by the Karl Fischer method (JIS K-2275). Table 8 shows the results.

As is clear from Table 8, the cyclic ketal and the cyclic acetal used in the product of the present invention have extremely low hygroscopicity as compared with the polyalkylene glycol, and are equivalent to the ester.

Example 9 Cyclic ketal A ₁ used in the product of the present invention obtained in Production Example,
For oil e (ester) used in the comparative product and A _2, was subjected to compressor tested using a commercially available rotary compressor.

A rotary compressor was charged with 170 g of oil whose water concentration had been adjusted to 20 ppm or less in advance and 60 g of 1,1,1,2-tetrafluoroethane (HFC134a).
A continuous exercise was performed at 500C for 500 hours.

After 500 hours, the cyclic ketals A ₁ and A ₂ have less coloration and no change in hydroxyl value than the oil e used as a comparative product, and also have decomposed products and no degradation in gas chromatography analysis or gel permeation chromatography analysis. No polymer was found, and the oil stability was good. Further, as shown in Table 9, the wear of the sliding portion is smaller in the cyclic ketals A ₁ and A ₂ than in the oil e used for the comparative product, and is superior in lubricity. Further, the sludge adhered state at the discharge portion is less favorable for the cyclic ketals A ₁ and A ₂ compared to the oil e used for the comparative product.

For cyclic ketal A ₂ used in the present invention product obtained in Example 10 Production Example were examined lubricity using Falex test.

50ppm cyclic ketal A ₂ to low-sulfur gas oil (S = 0.04%)
And operated under a load of 150 (lb) for 3 hours in an atmosphere of 25 ° C., and the amount of wear of the V block and the pin after the operation was examined. Table 10 shows the results.

Table 10 As is apparent, the present invention product 22 with the addition of cyclic ketal A ₂ has less abrasion amount than the comparative product 5 is not added, even more, the sulfur concentration is 0.2% light oil (comparative product 6)
Less wear and excellent lubricity.

For cyclic ketal A ₂ used in the present invention product obtained in Example 11 Production Example it was examined lubricity using Soda pendulum test.

50ppm cyclic ketal A ₂ to low-sulfur gas oil (S = 0.04%)
And the friction coefficient at 25 ° C. was measured. Table 11 shows the results.

Table 11 As is apparent, the present invention product 22 with the addition of cyclic ketal A ₂ are smaller coefficient of friction than comparative product 5 is not added, even more, the sulfur concentration of 0.2% of the gas oil (comparative product 6)
It has a lower coefficient of friction and better lubricity.

Example 12 cyclic ketal A ₂ used in the product of the present invention obtained in Production Example,
In order to investigate the electrical insulation properties of D ₂ , F ₂ , I ₂ , K, L ₂ , M and oil b (polyalkylene glycol) used as a comparative product, JI
The relative dielectric constant at 25 ° C. was measured based on SC-2101. Table 12 shows the results.

As is evident from Table 12, the products of the present invention had low relative dielectric constants, and all had good electrical insulation.

In addition, the cyclic ketals A ₂ , D ₂ , K, M, and the cyclic acetal L ₂ , which do not contain an ether bond, have a lower dielectric constant and are electrically insulating compared to the cyclic ketal F ₂ and the cyclic acetal I ₂ containing one ether bond. It was excellent.

Synthesis Example 1 1.2: 3.4: 5.6-Tri-O- (2-methylpropylidene)
Sorbitol (1) 1.3: 2.4: 5.6-Tri-O- (2-methylpropylidene)
Synthesis of a mixture of sorbitol (2): thermometer, reflux condenser, Dean-Stark trap,
In a 3 liter reaction vessel equipped with a calcium chloride tube and a stirrer, 450 g (2.470 mol) of D-sorbitol, 588 g (8.154 mol) of isobutyraldehyde, 4.70 g (0.0247 mol) of paratoluenesulfonic acid monohydrate and petroleum ether ( (bp 30-60 ° C) 400 ml was charged. The temperature was raised with stirring, the reaction was carried out at 40 to 65 ° C. for 15 hours, and the calculated amount of water was distilled off. After the completion of the reaction, the mixture was cooled to 60 ° C., and sodium carbonate (5.24 g) was added.
(0.0494 mol), stirred at 60 ° C for 30 minutes, and added water
100 g was added and the mixture was stirred at 60 ° C. for 30 minutes. After standing and separating, the lower layer was removed, washed with 100 g of saturated saline, and evaporated to obtain a mixture of the crude title compounds (1) and (2) (868.03 g). Obtained. This was distilled under reduced pressure to give the title compound (1),
800.17 g of the mixture of (2) was obtained.

Yield 94.0%, bp 137-149 ° C / 0.3-0.6 mmHg, gas chromatography purity 99.0% (title compound (1) /
Mixing ratio of (2) is 88/12 <weight ratio>), hydroxyl value 6.0mg
KOH / g (theoretical 0).

Spectrum of mixture of title compounds (1) and (2) IR (NEAT, cm^-1): 2972,2936,2884 (CH stretch), 147
6,1406,1368 (CH bending angle), 1194,1106,1038 (CO-
C expansion and contraction), 722 (CH_TwoSideways)¹H NMR (CDCl_Three, δ ppm): 0.58 to 1.49 (18H, multiple line, -CH ₃) 1.53 to 2.13 (3H, multiple lines, -CH (CH ₃)₂) 3.32 to 3.70, 4.50 to 4.97 (3H, multiple lines, (-O-)_TwoCH
−) 3.70 to 4.50 (8H, multiple lines, −CH _TwoCHCHCHCHCH
₂-) Prepare 1.0 g of a mixture of the title compounds (1) and (2)
By silica gel thin layer chromatography.
Rf value 0.6 using sun / ethyl acetate = 9/1 as developing solvent
0.63 g of the title compound (1) having an Rf value of 0.5
0.09 g of the title compound (2) was obtained as a part.

¹³ C NMR (CDCl ₃ , δ ppm) of the title compound (1): 107.7-
109.1 showed a 5-membered ring acetal structure.

¹³ C NMR (CDCl ₃ , δ ppm) of the title compound (2): 107.7-
109.1 and 104.9 showed a 5-membered acetal structure and a 6-membered ring acetal structure, respectively (the intensity ratio between the peak at 107.7 to 109.1 and the peak at 104.9 was 1: 2).

Synthesis Example 2 1.2: 3.4: 5.6-Tri-O- (3,5,5-trimethylhexylidene) sorbitol (3) 1.3: 2.4: 5.6-Tri-O- (3,5,5-trimethylhexylidene ) Synthesis of a mixture of sorbitol (4): thermometer, reflux condenser, Dean-Stark trap,
In a 3 liter reaction vessel equipped with a calcium chloride tube and a stirrer, 170.76 g (0.937 mol) of D-sorbitol, 3,5,5
400 g (2.812 mol) of trimethylhexanal, 1.78 g (0.00936 mol) of paratoluenesulfonic acid monohydrate and 400 ml of hexane were charged. Raise the temperature while stirring, 79-81
The reaction was carried out at 8 ° C. for 8 hours, and the calculated amount of water was distilled off. After completion of the reaction, the mixture was cooled to 70 ° C., neutralized by adding 1.99 g (0.0188 mol) of sodium carbonate, and stirred at 70 ° C. for 30 minutes.
After adding 0 g, the mixture was stirred at 60 ° C. for 30 minutes and allowed to stand still for separation. After removing the lower layer, the mixture was washed with 100 g of saturated saline and evaporated to obtain 529.51 g of a mixture of crude title compounds (3) and (4). This is distilled under reduced pressure (bp 27-85 ° C / 0.5-0.9mmH
500.87 g of the residue obtained by top cutting according to g) was dissolved in 500 ml of hexane, and 25.04 g of activated clay (5% by weight versus residue)
And hexane was completely evaporated from the hexane solution obtained by washing with hexane, and 501.14 g of a mixture of the title compounds (3) and (4) was obtained.
I got

Yield 96.4%, gas chromatography purity 93.2%
(The mixing ratio of the title compound (3) / (4) was 31/69 <weight ratio>), and the hydroxyl value was 27.2 mgKOH / g (theoretical value 0).

 IR (NEAT, cm^-1): 2960,2908,2876 (CH expansion and contraction), 147
6,1414,1396,1368 (CH bending angle), 1132,1098,1042 (C
-OC stretching), 714 (CH_TwoSideways)¹H NMR (CDCl_Three, δ ppm): 0.77 to 1.40 (42H, multiple lines, -CH (CH ₃) CH _TwoC (CH
₃)₃) 1.40 to 2.49 (9H, multiple lines, -CH _TwoCH(CH_Three) CH_TwoC (C
H_Three)₃) 3.38 to 3.68, 4.48 to 5.15 (3H, multiple lines, (-O-)_TwoCH
−) 3.68 to 4.42 (8H, multiple lines, −CH _TwoCHCHCHCHCH
₂-) Synthesis Example 3 1.2: 3.4: 5.6-tri-O- (1-methylpropylidene)
Synthesis of sorbitol (5): thermometer, reflux condenser, Dean-Stark trap,
3 liter reaction volume equipped with nitrogen blowing tube and stirrer
336.84 g (1.849 mol) of D-sorbitol in a vessel,
800 g (11.094 mol) of tyl ketone, p-toluene sulfone
17.58 g (0.092 mol) of acid monohydrate and 200 ml of hexane were prepared.
I was crowded. Raise the temperature while stirring, and conduct the reaction at 69-79 ° C for 8 hours.
And distilled off the calculated amount of water. Cool to 60 ° C after completion of the reaction
And add 19.60 g (0.185 mol) of sodium carbonate to neutralize
After stirring at 60 ° C for 30 minutes, add 200g of water and add
The mixture was stirred for 30 minutes and allowed to stand still. After looking down the lower layer, get bored
Wash with 200 g of Japanese NaCl solution, evaporate to give the crude title compound.
(5) 643.75 g was obtained. This is distilled under reduced pressure and is labeled
606.71 g of compound (5) were obtained.

Yield 95.3%, bp 136-140 ° C / 0.6mmHg, gas chromatography purity 97.3%, hydroxyl value 12.9mgKOH / g (theoretical value 0).

Synthesis Example 4 1.2: 3.4: 5.6-Tri-O- (1-methylpropylidene)
Synthesis of sorbitol (5): In a 2 liter reaction vessel equipped with thermometer, reflux condenser, Dean-Stark trap and stirrer, 168.4 g (0.93 mol) of D-sorbitol, 400 g of methyl ethyl ketone (5.
6 mol) 8.8 g (0.046 mol) of paratoluenesulfonic acid monohydrate and 100 g of hexane were charged. The temperature was raised with stirring under a nitrogen atmosphere, and the reaction was carried out at 65 to 72 ° C for 7 hours, and a calculated amount of water was distilled off. After completion of the reaction, the mixture was cooled to 60 ° C, neutralized by adding 9.8 g (0.09 mol) of sodium carbonate, stirred at 60 ° C for 30 minutes, then added with 100 g of water, stirred at 60 ° C for 30 minutes, and allowed to stand still. did. After removing the lower layer, it was washed with saturated saline until neutral, and dried over anhydrous sodium sulfate.
The mixture was filtered to remove hexane, and 293.5 g of the crude title compound (5) was obtained.
I got

Crude yield 92.2%, hydroxyl value 18.0 mgKOH / g (theoretical value 0).

100 g of this was dissolved in 100 ml of hexane and purified by silica gel column chromatography. Hexane /
The fraction eluted with ethyl acetate = 8/2 was collected and evaporated to obtain 95 g of the title compound (5).

Gas chromatography purity 99.7%, hydroxyl value 0m
gKOH / g (theoretical 0).

IR (NEAT, cm ^-1 ): 2980, 2938, 2890 (CH stretch), 147
0,1380 (CH bending angle), 1242,1194,1140,1080 (C-O-
C stretching), 717 (CH _{2 ^{roll) 1 H NMR (CDCl 3,}} δppm): 0.72~1.10 (9H, _{multiplet, -CH 2 C H 3) 1.10~1.48} (9H, multiplet, (- O- _{) 2 C (C H 3)} -) 1.48~1.90 (6H, _{multiplet, -C H 2 CH 3) 3.71~4.31} (8H, _{multiplet, -C H 2 C H C H} C H C H C H
_2- ) Synthesis Example 5 1.2: 3.4: 5.6-Tri-O- (1,3-dimethylbutylidene)
Synthesis of sorbitol (7): thermometer, reflux condenser, Dean-Stark trap,
In a 3-liter reaction vessel equipped with a calcium chloride tube and a stirrer, 363.76 g (1.997 mol) of D-sorbitol, 1200 g (11.981 mol) of methyl isobutyl ketone, 18.99 g (0.0998 mol) of paratoluenesulfonic acid monohydrate and hexane 30
0 ml was charged. The temperature was raised while stirring, and the reaction was carried out at 93 to 98 ° C. for 23 hours, and the calculated amount of water was distilled off. After reaction 60
The mixture was cooled to ℃, neutralized by adding 21.16 g (0.1996 mol) of sodium carbonate, stirred at 60 ° C for 30 minutes, then added with 200 g of water, stirred at 60 ° C for 30 minutes, and separated by standing. After removing the lower layer, the residue was washed with 200 g of saturated saline and evaporated to obtain 736.65 g of the crude title compound (7). This was top-cut by distillation under reduced pressure (bp 30.5 to 141 ° C./2 to 0.7 mmHg), and 657.62 g of the residue obtained was 33 g of activated clay (5% by weight vs. residue).
After filtration under pressure (PTFE, 0.2 μm), 637.44 g of the title compound (7) was obtained.

Yield 74.5%, gas chromatography purity 93.1
%, Hydroxyl value 34.3 mgKOH / g (theoretical value 0).

Synthesis Example 6 1.2: 3.4: 5.6-Tri-O- (1,3-dimethylbutylidene)
Synthesis of sorbitol (7): thermometer, reflux condenser, Dean-Stark trap,
127.5 g (0.7 mol) of D-sorbitol, 420.7 g (4.2 mol) of methyl isobutyl ketone, 6.7 g (0.035 mol) of paratoluenesulfonic acid monohydrate were placed in a 1 liter reaction vessel equipped with a nitrogen blowing tube and a stirrer. 100 g of toluene was charged. The temperature was raised while stirring under a nitrogen stream, and a dehydration reaction under reduced pressure was performed at 92 ° C. for 8 hours. After the completion of the reaction, the mixture was cooled to 60 ° C, and neutralized by adding 10.6 g (0.1 mol) of sodium carbonate.
After stirring for 60 minutes, 60 g of water was added, and the mixture was stirred at 60 ° C. for 30 minutes, and allowed to stand for separation. After removing the lower layer, the mixture was washed with saturated saline until neutral. The toluene was distilled off to obtain 247.2 g of the crude title compound (7).

Crude yield: 82.4%, hydroxyl value: 33.2 mgKOH / g (theoretical value: 0).

100 g of this was dissolved in 100 ml of hexane and purified by silica gel column chromatography. Hexane /
The fraction eluted with ethyl acetate = 8/2 was collected and evaporated to obtain 90 g of the title compound (7).

Gas chromatography purity 99.4%, hydroxyl value 0m
gKOH / g (theoretical 0).

IR (NEAT, cm ^-1 ): 2984,2956,2876 (CH stretch), 147
0,1378 (CH bending angle), 1242,1186,1148,1096 (CO-
C stretching), 718 (CH _{2 ^{roll) 1 H NMR (CDCl 3,}} δppm): 0.78~1.10 (18H, _{multiplet, -CH 2 CH (C H 3} ) 2) 1.22~1.47 (9H, multiplet, _{(-O-) 2 C (C H} 3) -) 1.47~1.68 (6H, _{multiplet, -C H 2 CH (CH 3} ) 2) 1.68~2.03 (3H, multiplet, -CH ₂ C H (CH _{3) 2) 3.71~4.38} (8H, _{multiplet, -C H 2 C H C H} C H C H C H
_2- ) Synthesis Example 7 1.2: 3.4: 5.6-Tri-O- (1-methylpropylidene)
Synthesis of mannitol (17): 336.84 g (1.849 mol) of D-mannitol, 800.0 g of methyl ethyl ketone in a 3 liter reaction vessel equipped with a thermometer, reflux condenser, Dean-Stark trap and stirrer
(11.094 mol), paratoluenesulfonic acid monohydrate 17.5
8 g (0.092 mol) and 200 ml of hexane were charged. The temperature was raised while stirring under a nitrogen atmosphere, and the reaction was carried out at 68 to 76 ° C. for 10 hours, and a calculated amount of water was distilled off. After completion of the reaction, the mixture was cooled to 60 ° C, neutralized by adding 19.6 g (0.185 mol) of sodium carbonate, stirred at 60 ° C for 30 minutes, and then added with 200 g of water and added at 60 ° C.
The mixture was stirred for 30 minutes and allowed to stand still. After removing the lower layer, the residue was washed with 200 g of saturated saline and evaporated to obtain 639.06 g of the crude title compound (17). This was distilled under reduced pressure to obtain 605.76 g of a partially purified title compound (17) (yield: 95.
1%).

bp 136 to 140 ° C / 0.3 mmHg, gas chromatography purity 94.2%, hydroxyl value 12.7 mgKOH / g (theoretical value 0).

Kinematic viscosity at 40 ° C. 37.65 mm ² / s, Kinematic viscosity at 100 ° C. 3.726 mm ² / s 150 g of this was dissolved in 150 ml of hexane and purified by silica gel column chromatography. Hexane /
The fraction eluted with ethyl acetate = 8/2 was collected and evaporated to obtain 135 g of the title compound (17).

Gas chromatography purity 99.6%, hydroxyl value 0.
2 mg KOH / g (theoretical 0).

IR (NEAT, cm ^-1 ): 2986, 2944, 2890 (CH stretch), 146
7,1377 (CH bending angle), 1242,1191,1137,1077 (CO-
C stretching), 708 (CH _{2 ^{roll) 1 H NMR (CDCl 3,}} δppm): 0.72~1.13 (9H, _{multiplet, -CH 2 C H 3) 1.13~1.50} (9H, multiplet, (- O- _{) 2 C (C H 3)} -) 1.50~1.90 (6H, _{multiplet, -C H 2 CH 3) 3.88~4.37} (8H, _{multiplet, -C H 2 C H C H} C H C H C H
_2- ) Test Example 1 Kinematic viscosities (JIS K-2283) and pour points (JI- ₂ ) of the cyclic acetal of the present invention obtained in the synthesis example at 40 ° C and 100 ° C.
SK-2269) was measured. Table 13 shows the results.

Test Example 2 The compatibility of the cyclic acetal of the present invention obtained in the synthesis example and the comparative product with 1,1,1,2-tetrafluoroethane (HFC134a) was measured. That is, each oil concentration is 10 vol%, 20 vol%, 30 vol%, 4 vol% with respect to 1,1,1,2-tetrafluoroethane.
The low-temperature two-phase separation temperatures at 0 vol% and 50 vol% were measured. Table 14 shows the results.

As is clear from Table 14, the product of the present invention was superior in compatibility to the comparative product.

Test Example 3 The volume resistivity (measured based on JIS C-2101) at 25 ° C. of the cyclic acetal of the present invention obtained in the synthesis example and the comparative product was measured. Table 15 shows the results.

As is clear from Table 15, the product of the present invention was superior in volume resistivity to the comparative product.

Test Example 4 The cyclic acetal of the present invention obtained in the synthesis example and 1,1,1,
A composition with 2-tetrafluoroethane (HFC134a) and a comparative ester and 1,1,1,2-tetrafluoroethane (HFC134a)
The composition with FC134a) was tested for abrasion resistance using the Falex test.

100 ml of oil is heated to 80 ° C., and 1,1,1,2-tetrafluoroethane (HFC134a) is blown at a rate of 10 liters per hour, and 150 (lb)
The operation was carried out for 4 hours under the load described above, and the wear amount of the V block and the pin after the operation was examined. Table 16 shows the results.

As is evident from Table 16, the products of the present invention all had a small amount of abrasion and were excellent in abrasion resistance.

INDUSTRIAL APPLICABILITY The present invention provides an inexpensive synthetic lubricating oil that is excellent in thermal stability and oxidative stability, does not generate carboxylic acid by hydrolysis, has low hygroscopicity, and is inexpensive. Also, by blending such a synthetic lubricating oil and hydrofluorocarbon,
It is possible to provide an inexpensive refrigerator working fluid composition which is excellent in electric insulation and hygroscopicity, does not generate carboxylic acid by hydrolysis, and is inexpensive. Further, according to the present invention, a novel cyclic acetal useful as a synthetic lubricating oil can be obtained from inexpensive raw materials in a high yield and a high purity by a simple method.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C10N 20:02 30:02 30:06 30:08 40:16 40:30 (72) Inventor Koji Taira 1019 Hara, Wakayama-shi, Wakayama No. 4 (72) Inventor Akimitsu Sakai 1450 Nishihama, Wakayama City, Wakayama Prefecture (56) References JP-A-6-57243 (JP, A) JP-A 8-104687 (JP, A) (58) Field (Int.Cl. ⁶ , DB name) C07D 317 / 18,319 / 26 C10M 105/18

Claims (15)

(57) [Claims] 1. A ketalization reaction of at least one kind of polyhydric alcohol having an even number of valences of not less than 4 and not more than 10 which does not have an ether bond with at least one kind of the following compound A or B:
An acetalization reaction, a transketalization reaction or a transacetalization reaction, wherein the number of unreacted hydroxyl groups present in the cyclic ketal or the cyclic acetal obtained in the cyclic ketal or the cyclic acetal is a A synthetic lubricating oil characterized by containing a compound that is 2% or less based on the number of hydroxyl groups, Compound A: a carbonyl compound represented by the general formula (I) (In the formula, R ¹ represents a linear, branched, or cyclic alkyl group having 1 to 18 carbon hydrogen or C, R ² is 1 to the number of carbon atoms
Indicate 18 linear, branched or cyclic alkyl groups. Alternatively, R ¹ and R ² together represent an alkylene group having 2 to 36 carbon atoms. Compound B: ketal or acetal obtained from a carbonyl compound represented by the general formula (I) and a lower alcohol having 1 to 6 carbon atoms. 2. A polyhydric alcohol selected from the group consisting of diglycerin, ditrimethylolethane and ditrimethylolpropane, and the following compound A or B:
A ketal reactant, an acetalization reaction,
A cyclic ketal or a cyclic acetal obtained by a transketalization reaction or a transacetalization reaction, wherein the number of unreacted hydroxyl groups present in the cyclic ketal or the cyclic acetal is equal to the number of hydroxyl groups of the raw material polyhydric alcohol. A synthetic lubricating oil characterized by containing a compound of not more than 2% by weight, compound A: a carbonyl compound represented by the general formula (I) (In the formula, R ¹ represents a linear, branched, or cyclic alkyl group having 1 to 18 carbon hydrogen or C, R ² is 1 to the number of carbon atoms
Indicate 18 linear, branched or cyclic alkyl groups. Alternatively, R ¹ and R ² together represent an alkylene group having 2 to 36 carbon atoms. Compound B: ketal or acetal obtained from a carbonyl compound represented by the general formula (I) and a lower alcohol having 1 to 6 carbon atoms. 3. A ketalization reaction and an acetalization reaction of at least one kind of a polyhydric alcohol having an even number of tetravalent to octavalent having no ether bond and at least one kind of the following compound C or D: A cyclic ketal or a cyclic acetal obtained by a reaction, transketalization reaction or transacetalization reaction, wherein the number of unreacted hydroxyl groups present in the cyclic ketal or the cyclic acetal is the number of hydroxyl groups of the raw material polyhydric alcohol. A synthetic lubricating oil characterized by containing a compound of not more than 2% of the number, compound C: a carbonyl compound represented by the general formula (II) (Wherein, R ³ represents a hydrogen atom or a straight-chain having 1 to 12 carbon atoms, branched, or cyclic alkyl group, R ⁴ is 1 to carbon atoms
Shows 12 linear, branched, or cyclic alkyl groups. Alternatively, R ³ and R ⁴ together represent an alkylene group having 2 to 13 carbon atoms. The total carbon number of R ³ and R ⁴ is 1 to 13. Compound D: ketal or acetal obtained from a carbonyl compound represented by the general formula (II) and a lower alcohol having 1 to 6 carbon atoms. 4. A polyhydric alcohol selected from the group consisting of diglycerin, ditrimethylolethane and ditrimethylolpropane, and the following compound C or D:
A ketalization reaction, an acetalization reaction,
A cyclic ketal or a cyclic acetal obtained by a transketalization reaction or a transacetalization reaction, wherein the number of unreacted hydroxyl groups present in the cyclic ketal or the cyclic acetal is equal to the number of hydroxyl groups of the raw material polyhydric alcohol. A synthetic lubricating oil characterized by containing a compound of not more than 2% by weight, compound C: a carbonyl compound represented by the general formula (II) (Wherein, R ³ represents a hydrogen atom or a straight-chain having 1 to 12 carbon atoms, branched, or cyclic alkyl group, R ⁴ is 1 to carbon atoms
Shows 12 linear, branched, or cyclic alkyl groups. Alternatively, R ³ and R ⁴ together represent an alkylene group having 2 to 13 carbon atoms. The total carbon number of R ³ and R ⁴ is 1 to 13. Compound D: ketal or acetal obtained from a carbonyl compound represented by the general formula (II) and a lower alcohol having 1 to 6 carbon atoms. 5. The method according to claim 1, wherein the cyclic ketal or cyclic acetal is 1,2.
The synthetic lubricating oil according to any one of claims 1 to 4, comprising a 3-dioxolane structure and / or a 1,3-dioxane structure. 6. A synthetic lubricating oil comprising at least one cyclic ketal or acetal represented by the formula (IIIa), (IIIb), (IVa) or (IVb). (Wherein, R ³ represents a hydrogen atom or a straight-chain having 1 to 12 carbon atoms, branched, or cyclic alkyl group, R ⁴ is 1 to carbon atoms
Shows 12 linear, branched, or cyclic alkyl groups. Alternatively, R ³ and R ⁴ together represent an alkylene group having 2 to 13 carbon atoms. The total carbon number of R ³ and R ⁴ is 1 to 13. ) 7. A synthetic lubricating oil comprising at least one cyclic ketal or cyclic acetal represented by the formula (V) or (VI). (Wherein, R ³ represents a hydrogen atom or a straight-chain having 1 to 12 carbon atoms, branched, or cyclic alkyl group, R ⁴ is 1 to carbon atoms
Shows 12 linear, branched, or cyclic alkyl groups. Alternatively, R ³ and R ⁴ together represent an alkylene group having 2 to 13 carbon atoms. The total carbon number of R ³ and R ⁴ is 1 to 13. ) 8. A refrigerating machine working fluid composition comprising a refrigerating machine oil containing a cyclic ketal or a cyclic acetal according to claim 2 and a hydrofluorocarbon. 9. The method of claim 1, wherein the hydrofluorocarbon and the refrigerating machine oil are hydrofluorocarbon / refrigerating machine oil = 50/1 to 1/20.
The working fluid composition for a refrigerator according to claim 8, which is contained in a (weight ratio). 10. The following general formula (i) or (ii) (Wherein, R ⁵ represents a hydrogen atom, in which case R ⁶ has 3 carbon atoms)
Or a linear or branched alkyl group having 4 to 21 carbon atoms. Alternatively, R ⁵ represents a linear or branched alkyl group having 1 to 21 carbon atoms, in which case R ⁶ represents a linear or branched alkyl group having 2 to 21 carbon atoms. ) Cyclic acetals represented by 11. R ⁵ is a hydrogen atom and R ⁶ is a branched alkyl group having 3 carbon atoms or a linear or branched alkyl group having 4 to 12 carbon atoms, or R ⁵ is a linear or branched alkyl group having 1 to 12 carbon atoms. 11. The cyclic acetal according to claim 10, wherein R ⁶ is a linear or branched alkyl group having 2 to 12 carbon atoms. 12. R ⁵ is a hydrogen atom and R ⁶ is a branched alkyl group having 3 to 12 carbon atoms, or R ⁵ is a linear or branched alkyl group having 1 to 12 carbon atoms and R ⁶ is 2 to 2 carbon atoms. 11. The cyclic acetal according to claim 10, which is 12 linear or branched alkyl groups. 13. The cyclic acetal according to claim 10, wherein the hexahydric alcohol residue is provided by sorbitol. 14. The following formula (iii): And a general formula (iv) (Wherein, R ⁵ represents a hydrogen atom, in which case R ⁶ has 3 carbon atoms)
Or a linear or branched alkyl group having 4 to 21 carbon atoms. Alternatively, R ⁵ represents a linear or branched alkyl group having 1 to 21 carbon atoms, in which case R ⁶ represents a linear or branched alkyl group having 2 to 21 carbon atoms. 11. The cyclic acetal according to claim 10, wherein the cyclic acetal represented by the general formula (i) or (ii) is obtained by reacting a carbonyl compound represented by the formula or a reactive derivative thereof (ketal or acetal) in the presence of an acid catalyst. Manufacturing method. 15. The method according to claim 14, wherein the hexahydric alcohol is sorbitol.