JPH0259832B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel polyhydric alcohol derivative and a method for producing the same. For more information, see Eq. (In the formula, R and R' are different from each other and are atoms or groups selected from a hydrogen atom, a chlorine atom, a carboxyl group, an alkyl group having 1 to 3 carbon atoms, and an alkoxy group having 1 to 3 carbon atoms in the alkyl part. , n represents an integer of 1 or 2) and a method for producing the same. According to the production method of the present invention, the benzylidene-polyhydric alcohol represented by the above formula has the following properties: (a) 0.8 to 1.2 mol per mol of polyhydric alcohol;

[Formula] (in the formula, represents an atom or group selected from a hydrogen atom, a chlorine atom, a carboxyl group, an alkyl group having 1 to 3 carbon atoms, and an alkoxy group having 1 to 3 carbon atoms in the alkyl part) as an acid catalyst in the presence of at least 40% conversion to monobenzylidene polyhydric alcohol at temperatures between 10 and 50 °C
(b) Next, per 1 part by weight of the polyhydric alcohol charged.
0.8 to 1.2 mol per mol of aqueous reaction medium and charged polyhydric alcohol of 2.5 parts by weight or more

[Formula] (Different from R, R' is an atom selected from a hydrogen atom, a chlorine atom, a carboxyl group, an alkyl group having 1 to 3 carbon atoms, and an alkoxy group having 1 to 3 carbon atoms in the alkyl moiety, or (representing a group), react in a suspended state at room temperature in the presence of an acid catalyst, and if necessary age the resulting suspension. In this specification, the term "polyhydric alcohol" is used to mean sorbitol and xylitol. Formula of the invention The substituents R and R' in the novel benzylidene polyhydric alcohol derivative are different from each other, and the alkyl groups having 1 to 3 carbon atoms that they represent include, for example, methyl group, isopropyl group, butyl group, ethyl group, etc. However, methyl and ethyl groups are preferred, and examples of alkoxy groups whose alkyl moiety has 1 to 3 carbon atoms include methoxy, ethoxy, and butoxy groups, with methoxy and ethoxy groups being preferred. Further, the substitution position of R and R' may be any of the para, ortho, and meta positions, but the para position is preferred from the viewpoint of production. Particularly preferred examples of substituents R and R' are methyl and ethyl. Also n
A polyhydric alcohol derivative with =2 is more preferred. Examples of compounds with such formulas include 1,3
- p-methylbenzylidene-2,4-p chlorobenzylidene-sorbitol, 1,3-benzylidene-2,4-p chlorobenzylidene-sorbitol, 1,3-p methylbenzylidene-2,4-p
Isopropylbenzylidene-sorbitol, 1,
3-benzylidene-2,4-p isopropylbenzylidene-sorbitol, 1,3-p methylbenzylidene-2,4-p ethylbenzylidene-sorbitol, 1,3-p chlorobenzylidene-2,
4-pmethylbenzylidene-sorbitol, 1,
3-p methoxybenzylidene-2,4-p methylbenzylidene-sorbitol, 1,3-p methylbenzylidene-2,4-benzylidene-sorbitol, 1,3-benzylidene-2,4-p ethylbenzylidene-sorbitol, 1, 3-pbenzylidene-2,4-pcarboxybenzylidene-sorbitol, 1,3-pmethylbenzylidene-
2,4-p carboxybenzylidene sorbitol, 1,3-p ethylbenzylidene-2,4-p
Carboxybenzylidene sorbitol, 1,3-
p-methylbenzylidene-2,4-pchlorobenzylidene-xylitol, 1,3-benzylidene-
2,4-p chlorobenzylidene-xylitol,
1,3-p methylbenzylidene-2,4-p isopropylbenzylidene-xylitol, 1,3-
Benzylidene-2,4-p isopropylbenzylidene-xylitol, 1,3-p methylbenzylidene-2,4-p ethylbenzylidene-xylitol, 1,3-p chlorobenzylidene-2,4-
p-methylbenzylidene-xylitol, 1,3-
pMethoxybenzylidene-2,4-pmethylbenzylidene-xylitol, 1,3-pmethylbenzylidene-2,4-benzylidene-xylitol, 1,3-benzylidene-2,4-pethylbenzylidene-xylitol, 1,3- Benzylidene-2,4-p carboxybenzylidene-xylitol, 1,3-p methylbenzylidene-2,4
-p carboxybenzylidene xylitol, 1,
Examples include 3-p ethylbenzylidene-2,4-p carboxybenzylidene xylitol. Among these polyhydric alcohol derivatives, 1,3-
pMethylbenzylidene-2,4-pchlorobenzylidene-sorbitol, 1,3-pchlorobenzylidene-2,4-pmethylbenzylidene-sorbitol, 1,3-pmethylbenzylidene-2,4
-p-ethylbenzylidene-sorbitol, 1,3
-p-Ethylbenzylidene-2,4-pmethylbenzylidene-sorbitol, 1,3-benzylidene-2,4-pmethylbenzylidene-sorbitol, 1,3-pmethylbenzylidene-2,4-benzylidene sorbitol, etc. Extremely useful as an additive for resins. It is difficult to produce the dibenzylidene polyhydric alcohol of the formula of the present invention by conventional methods for producing dibenzylidene polyhydric alcohol, where R=R' in the formula. i.e. sorbitol or xylitol,

[Formula] and

The method of adding an acid catalyst to the mixture of [Formula] and heating it in an alcohol solution is the same as the conventional method of using cyclohexane as a solvent and removing the water produced by the reaction as an azeotrope with cyclohexane. Dibenzylidene sorbitol or dibenzylidene xylitol could not be synthesized at all. As a result of repeated research on the method for producing dibenzylidene polyhydric alcohol of the formula, the present inventors discovered a production method for producing the dibenzylidene polyhydric alcohol of the formula in a sufficiently high yield that is industrially practicable. That is, with sorbitol or xylitol in the presence of an acid catalyst.

The reaction with [Formula] is carried out at a temperature of 10 to 50°C in the absence of an organic solvent, except when R is chloro, etc. [Step (a)]. When the conversion rate to sorbitol or (R-substituted) benzylidene xylitol reaches 40% or more,

[Formula] The dibenzylidene polyhydric alcohol of the formula can be produced in high yield by adding a large amount of an aqueous reaction medium and an additional acid catalyst, and then carrying out the reaction in a slurry form at room temperature [step (B)]. It became. Another feature of the present invention is that dibenzylidene polyhydric alcohols and monobenzylidene polyhydric alcohols other than those of the formula are not produced as by-products at all. The method for producing benzylidene polyhydric alcohol of the formula of the present invention is represented by the following chemical reaction: The reaction in step (a) of the present invention involves reacting a concentrated aqueous solution (70% by weight or more) of sorbitol or xylitol with benzaldehyde at temperature in the presence of an acid catalyst to synthesize monobenzylidene sorbitol or monobenzylidene xylitol. It is.
Sorbitol or xylitol mono (R substitution)
When the conversion rate to benzylidene/derivative reaches 40% or more, a large amount of aqueous reaction medium etc. is added and the reaction proceeds to step (B).The reaction in step (a) is continued as is. This is because the reaction becomes extremely viscous due to crystals of monobenzylidene sorbitol or monobenzylidene xylitol that are produced, and the progress of the subsequent reaction is inhibited. Thus, in the production of the present invention, a large amount of aqueous reaction medium is added to the reaction system before the reaction in step (a) progresses and becomes significantly viscous. The reaction proceeds and is completed in a dispersed suspension state. Therefore, the conversion rate of sorbitol to mono(R-substituted) benzylidene sorbitol or mono(R-substituted) benzylidene xylitol in step (a) is 70%.
If the reaction progresses too far beyond this point, the reaction system will become extremely viscous and in severe cases it will solidify, making it difficult to proceed to step (B).On the other hand, if the conversion rate is less than 40%, it will be difficult to proceed to step (B). In this case, the reaction in step (b) takes a significantly long time and reduces the yield. Therefore, at the time of transition from stage (a) to stage (b), the above conversion rate is 40% higher, preferably 40 to 70%.
It is necessary that On the other hand, in the reaction at step (a), the

One of the characteristics of the production method of the present invention is that [formula] is often in a liquid state, so there is no need to add a solvent or other reaction medium. When benzaldehyde is used, it is preferable to use a solvent such as alcohol, and other inert organic solvents may be added if necessary. The reaction temperature in step (a) is 10 to 50°C, preferably 10°C.
The reaction temperature is carried out in the range of ~40°C, but if the reaction temperature is too high above 50°C, di(R-substituted) benzylidene sorbitol or di(R-substituted) benzylidene xylitol will be formed in step (a), which is undesirable. , also 10
If the temperature is too low, below .degree. C., the yield of the compound will decrease, which is not preferable. Also

The amount of [Formula] to be charged is 0.8 to 1.3 mol, preferably 0.9 to 1.2 mol, particularly preferably about 1.1 mol, per 1 mol of sorbitol or xylitol.

[Formula] is used. If the amount exceeds 1.3 mol, unreacted

[Formula] remains and purification of the target compound becomes difficult, which is undesirable, and if the amount is too small (less than 0.8 mol), the yield of the target compound decreases, which is undesirable. On the other hand, the aqueous reaction medium used in the reaction in step (b) refers to an inert reaction medium containing 50% by weight or more of water, such as water, a mixed medium of water and alcohols, water and ethyl cellosolve, etc. mixed media,
A mixed medium of water and N-methyl-pyrrolidone, a mixed medium of water and dimethylformamide, etc. are used, and water is particularly preferred. Such aqueous reaction media may be added as a solvent for the acid catalyst used, such as water in hydrochloric acid. The amount of aqueous reaction medium used must be 2.5 parts by weight or more per 1 part by weight of sorbitol or xylitol. If the aqueous reaction medium is less than 2.5 parts by weight, the viscosity increases during the reaction and stirring becomes difficult, which is not preferable. Preferably, the amount of water during the reaction in step (b) (including condensed water produced by the reaction) is greater than the amount of D-sorbitol or xylitol charged at the beginning of step (b).
1 to 3 parts by weight, particularly preferably 1.5 to 3 parts by weight
Adjusted to 2.5 parts by weight. If the water content is too high, exceeding 3 parts by weight, the yield of the target compound will decrease, which is undesirable, and if it is too low, such as less than 1 part by weight, the viscosity will be high, making stirring difficult. The reaction temperature in step (b) is room temperature, preferably 15-25℃.
will be adopted. If the reaction temperature is higher than room temperature, the yield of benzylidene sorbitol or benzylidene xylitol of the formula will decrease, which is undesirable.On the other hand, if the reaction temperature is lower than room temperature, the reaction time will become longer, which is undesirable. Also

The amount of formula [formula] to be charged is 0.8 to 1.3 mol, preferably 0.9 to 1.2 mol, particularly preferably about 1.1 mol, per mol of sorbitol or xylitol. If the amount exceeds 1.3 moles, unreacted aldehyde remains and it becomes difficult to purify the target compound, which is not preferable.
If the amount is too small, less than 0.8 mol, the yield will decrease, which is not preferable. The reaction time in step (b) generally takes about 6 to 8 hours, although it varies depending on the amount charged. As the reaction in step (b) progresses, benzylidene sorbitol or benzylidene xylitol of the formula formed becomes precipitated and suspended in the aqueous reaction medium in the form of fine powder. The suspension gradually increases and the reaction is terminated when a stable suspension state is reached. Thereafter, by neutralization, separation, washing and conversion, fine powder crystals of benzylidene sorbitol or benzylidene xylitol of the formula are easily obtained. Yields are usually about 60-65% based on sorbitol or xylitol. It is preferable to leave the suspension after completing the reaction in step (a) as it is at room temperature for about 12 hours to ripen it, and then neutralize it, separate it, wash it with water, and dry it. - The yield of sorbitol or benzylidene xylitol is improved to about 65-75%. The acid catalyst used in step (a) and step (b) is not particularly limited, and any organic or inorganic acid can be used as a catalyst. Examples of inorganic acids include hydrochloric acid and sulfuric acid; examples of organic acids include p-toluenesulfonic acid and hexahydrophthalic anhydride; p-toluenesulfonic acid, sulfuric acid, and hydrochloric acid are preferably used. The amount of acid catalyst used is 0.01 to 0.5 parts by weight, preferably 0.03 to 0.01 parts by weight, per 1 part by weight of charged sorbitol or xylitol in step (a), and an additional 0.02 to 0.5 parts by weight, preferably 0.05 parts by weight in step (b). ~0.3 part by weight is additionally added. If the entire amount of the catalyst additionally added in step (b) is added at the beginning of the reaction together with the catalyst in step (a), the reaction will proceed too much and di(R-substituted)benzylidene sorbitol or di(R-substituted) benzylidene sorbitol or di(R-substituted) benzylidene sorbitol or
Substituted) benzylidene xylitol is produced, which is not preferable. Furthermore, the acid catalysts used in the (a) and (b) stages do not necessarily have to be of the same type, and different types of acids may be used in the (a) and (b) stages. The reaction of the present invention is preferably carried out in an atmosphere of an active gas such as nitrogen, since oxidation of the aldehyde is prevented, but it can also be carried out in air, and may be carried out appropriately under normal pressure or elevated pressure. In addition, the raw materials sorbitol and xylitol are usually subjected to the reaction in the form of a concentrated aqueous solution of 70% by weight or more, but when using a solid powder, a small amount of water is appropriately added and dissolved to use the solution as a liquid. The reaction of the present invention is carried out under stirring throughout each stage, and in the reaction of stage (a), the viscosity increases as the reaction progresses. It is preferable to use this as a guideline, and in preferred embodiments of the present invention such as Example 1, the time when the torque increases to about three times the starting point of the reaction is the point at which the conversion rate of sorbitol to mono-R-substituted benzylidene sorbitol is about 40 to 45%. corresponds to This state is usually reached about 30 to 90 minutes after the reaction starts. Therefore, according to the production method of the present invention, almost no organic solvent is used, almost no mono- or non-formula dibenzylidene sorbitol (or xylitol) is produced as a by-product, and a high yield is obtained. It has become possible to obtain dibenzylidene sorbitol of the formula or dibenzylidene xylitol of the formula in the form of an easy-to-handle slurry. The novel dibenzylidene sorbitol or dibenzylidene xylitol of the formula of the present invention is useful as a gelling agent for organic liquids and as an additive for polyolefin resins, particularly when the dibenzylidene sorbitol of the formula is added to polyolefin resins. , greatly improves the transparency and dimensional stability of molded products or sheets. As such an additive for polyolefin resin, the present inventor proposed in JP-A No. 55-160041 to use a small amount of tribenzylidene sorbitol in combination with dibenzylidene sorbitol corresponding to R=R' in the formula compound. It was subsequently discovered that the molded product had the disadvantage of being slightly susceptible to staining. Dibenzylidene of the formula of the invention
Sorbitol is an excellent additive that overcomes these drawbacks, and the dibenzylidene sorbitol formula obtained by the production method of the present invention can be used as is for such purposes without any purification. It is something that can be done. EXAMPLES The present invention will be explained in more detail with reference to Examples below. Note that parts, percentages, etc. in this specification are based on weight unless otherwise specified. Example 1 (A) 120 g (1 mole) of p-methylbenzaldehyde, 270 g (1 mole) of a 70% aqueous solution of D-sorbitol, and 10 g of p-toluenesulfonic acid are placed in a reaction vessel and reacted with stirring at a temperature of 35°C. After a while, a large amount of white microcrystals precipitated in the mixture in the reactor, and after 45 minutes, it became creamy and the torque of the stirrer reached about three times that at the start of the reaction. At this point, monop-methylbenzylidene sorbitol was produced. The amount was 43% of the theoretical value. p-ethylbenzaldehyde is added to the white creamy reaction product obtained by the above one-step reaction.
Add 134g (1 mol) of hydrochloric acid as an additional catalyst.
% aqueous solution was added to proceed to the second stage. The temperature was lowered to 25°C and stirring was continued for 6 hours at this temperature.The resulting white suspension was diluted with 10% caustic soda.
The catalyst was neutralized by treatment with an aqueous solution, washed separately with water using a centrifuge, and dried to obtain 223 g of 1,3p methylbenzylidene 2,4p ethylbenzylidene sorbitol with a purity of 97%, which is about 56% of the theoretical yield. The ¹³ CNMR spectrum of this product (taken by JEOL FX-100 high-resolution nuclear magnetic resonance apparatus) is shown in Figure 1. The melting point of this product was 200-204. (B) A suspension is prepared in the same manner as in the first and second stage reactions of (A) above, and this is allowed to stand at room temperature for another 12 hours to ripen, resulting in the same purity of 97% as obtained in (A). 1,
279 g (approximately 70% of the theoretical amount) of 3p methylbenzylidene 2,4p ethylbenzylidene sorbitol was obtained. Example 2 106 g (1 mol) of benzaldehyde and 270 g (1 mol) of a 70% aqueous solution of D-sorbitol and 50% sulfuric acid
Put 20g into a reaction vessel and react at 15°C with stirring. Microcrystals form in the mixture in the reactor.
After 30 minutes, the torque of the stirrer reached about three times the initial torque. At this point, the amount of monobenzylidene sorbitol produced was 24% of the theoretical value. 120 g of p-methylbenzaldehyde was added to the white creamy reaction product obtained from the first stage reaction.
(1 mol) was added, and 400 g of a 10% aqueous solution of hydrochloric acid was added as an additional catalyst to proceed to the second stage. Thereafter, 1, with a purity of 95%, was prepared in exactly the same manner as B in Example 1.
258 g (approximately 70% of the theoretical amount) of 3-benzylidene 2,4p methylbenzylidene sorbitol was obtained. The melting point was 190-193°C. ¹³ CNMR spectrum is shown in Figure 2. Example 3 106 g (1 mol) of benzaldehyde, 270 g (1 mol) of a 70% aqueous solution of D-sorbitol, and 15 g of hexahydrophthalic anhydride are placed in a reaction vessel and reacted with stirring at a temperature of 20°C. Microcrystals formed in the mixture in the reactor, and after 45 minutes, the torque of the stirrer increased to about three times the initial torque. At this point, the amount of monobenzylidene sorbitol produced was 40% of the theoretical value. 134 g of p-ethylbenzaldehyde was added to the white creamy reaction product obtained in the first stage reaction.
(1 mol) was added, and 400 g of a 10% aqueous solution of hydrochloric acid was added as an additional catalyst to proceed to the second stage. Thereafter, 1, with a purity of 96%, was prepared in exactly the same manner as B in Example 1.
302 g (about 72% of theory) of 3-benzylidene 2,4p ethylbenzylidene sorbitol was obtained. The melting point is
The temperature was 192-195℃. ¹³ CNMR spectrum is shown in Figure 3. Example 4 Add 170 g of methyl alcohol to 140 g (1 mole) of p-chlorobenzaldehyde, dissolve by heating, and put the entire amount into a reaction vessel. Next, 220g (1 mol) of a 70% aqueous solution of xylitol
Add 13 g of p-toluenesulfonic acid and react at a temperature of 35°C. Microcrystals were formed in the mixture in the reactor, and after 30 minutes it became creamy, and the torque of the stirrer reached about three times the initial torque. At this point, the amount of monop-chlorobenzylidene xylitol produced was 43% of the theoretical value. 120g of p-methylbenzaldehyde was added to the creamy reaction product obtained in the first stage reaction.
Add (1 mol) an aqueous solution of hydrochloric acid as an additional catalyst.
400g was added and transferred to the second stage. Thereafter, 1, with a purity of 93%, was prepared in exactly the same manner as B in Example 1.
3p chlorobenzylidene 2,4p methylbenzylidene xylitol 284g (approximately 70% of theoretical amount) H-
The NMR spectrum is shown in Figure 4. Example 5 136 g (1 mol) of p-methoxybenzaldehyde and a 70% aqueous solution of D-sorbitol ((1 mol) and 50%
Put 20g of sulfuric acid into a reaction vessel and react at a temperature of 40°C with stirring. After a while, white microcrystals precipitated out, and after 2 hours, the mixture turned into a pale pink cream, and when stirring was continued, the torque of the stirrer reached three times that at the start of the reaction in 2.5 hours. At this point, the amount of monop-methoxybenzylidene sorbitol produced was the theoretical value of 39
It was %. p-methylbenzaldehyde is added to the pink cream-like reaction product obtained in the first stage reaction.
120 g (1 mole) was added, and furthermore, 400 g of a 10% aqueous solution of hydrochloric acid was added as an additional catalyst to proceed to the second stage.
The temperature was lowered to 25° C. and stirring was continued at this temperature for 8 hours. The resulting pink suspension was treated with a 10-aqueous solution of caustic soda to neutralize the acid catalyst, washed with water in a centrifuge, and dried. 200 g of 1,3-p methoxybenzylidene 2,4p methylbenzylidene sorbitol with 86% purity was obtained. This is about 50% of the theoretical amount. When the reaction product was further aged at room temperature for 24 hours, the yield increased to 62%. After being thoroughly washed with water and dried, it becomes a white powder with a melting point of 218°C. ^{The 13} C-NMR spectrum is shown in Figure 5. Example 6 150 g (1 mol) of 4-carboxybenzaldehyde (p-carboxybenzaldehyde) was mixed in advance with 50 parts of isopropyl alcohol and ethyl cellosolve.
Heat and dissolve in 300 g of 50 parts of mixed solvent. After cooling, a 70% aqueous solution of D-sorbitol and p-toluenesulfonic acid were added thereto and reacted in the same manner as in Example 5 in a reaction vessel. Next, 106g of benzaldehyde
(1 mol) was added as an additional catalyst in a 10% aqueous solution of hydrochloric acid.
400g was added and moved to the second stage. After stirring for 8 hours at a temperature of 30°C, the mixture was left to mature for 24 hours, and then the catalyst was removed only by washing with water. When dried, it is 76% pure 1,3
-p Carboxybenzylidene 183g of 2,4-benzylidene sorbitol was obtained. 46% of theoretical amount
It was hot. Although the yield is somewhat poor, it is thought that it will become even better by extending the ripening time. The melting point of the product is 198°C. ^13C -NMR spectrum as 6th
As shown in the figure.

[Brief explanation of the drawing]

1, 2, 3, 4, 5 and 6 are NMR spectra of dibenzylidene polyhydric alcohol according to the present invention.

Claims (1)

[Claims] 1 formula (In the formula, R and R' are different from each other and are atoms or groups selected from a hydrogen atom, a chlorine atom, a carboxyl group, an alkyl group having 1 to 3 carbon atoms, and an alkoxy group having 1 to 3 carbon atoms in the alkyl part. , where n is 1
or an integer of 2). 2 (a) 0.8 to 1.3 mol of [formula] per mol of polyhydric alcohol (wherein R is a hydrogen atom, a chlorine atom, a carboxyl group, a carbon number of 1 to 3
The number of carbon atoms in the alkyl group and alkyl moiety is 1 to
(representing an atom or group selected from the alkoxy groups of 3) in the presence of an acid catalyst at a temperature of 10 to 50°C until the conversion rate to monobenzylidene polyhydric alcohol reaches at least 40%. ) Then, per 1 part by weight of polyhydric alcohol
0.8 to 1.3 mol of [formula] per 2.5 parts by weight or more of aqueous reaction medium and 1 mol of charged polyhydric alcohol (wherein R' is different from the above R, and a hydrogen atom, a chlorine atom, a carboxyl group, a carbon number of 1 to 3 (representing an atom or group selected from an alkyl group and an alkoxy group whose alkyl moiety has 1 to 3 carbon atoms) is added, and the reaction is carried out in a suspended state at room temperature in the presence of an acid catalyst to produce as necessary. A formula characterized by: aging a suspension of (wherein R, R' and n have the above meanings)
A method for producing polyhydric alcohol derivatives. 3. The process according to claim 2, wherein the reaction in step (a) is carried out to a conversion rate of 40 to 70% to monobenzylidene-polyhydric alcohol. 4. The process according to claim 3, wherein the reaction in step (a) is carried out to a conversion rate of 45 to 60% to monobenzylidene-polyhydric alcohol. 5. The manufacturing method according to any one of claims 1 to 4, wherein an acid catalyst is additionally added in step (b). 6 Claims 1 to 5 in which the acid catalyst is hydrochloric acid
The manufacturing method described in any of the paragraphs. 7. The manufacturing method according to claims 1 to 6, wherein the aqueous suspension obtained as a result of the reaction in step (b) is aged. 8 The water content of the reaction system in step (b) is 1 to 3 parts by weight per 1 part by weight of D-sorbitol charged at the beginning of step (b).
The manufacturing method according to any one of claims 1 to 7, wherein the amounts are parts by weight. 9 The water content of the reaction system in step (b) is 1.5 to 1.5 parts by weight of D-sorbitol charged at the beginning of step (b).
The manufacturing method according to any one of claims 1 to 8, wherein the amount is 2.5 parts by weight. 10. The manufacturing method according to any one of claims 1 to 9, wherein the reaction temperature in step (a) is 10 to 40°C. 11. The production method according to any one of claims 1 to 10, wherein in the reaction in step (a), the conversion rate to monobenzylidene polyhydric alcohol is measured by increasing the torque of a stirrer. 12 1,3-pethylbenzylidene-2,4-
The polyhydric alcohol derivative according to claim 1, which is paramethylbenzylidene sorbitol. 13 The polyhydric alcohol derivative according to claim 1, which is 1,3-benzylidene-2,4-pmethylbenzylidene-sorbitol. 14. The polyhydric alcohol derivative according to claim 1, which is 1,3-benzylidene-2,4-pethylbenzylidene-xylitol.