JP4648066B2 - Method for producing tertiary alcohol - Google Patents

Description

  The present invention relates to a method for producing a high-purity tertiary alcohol, and more particularly, to a method for producing a tertiary alcohol with reduced contamination of lead as an impurity mixed in the production process.

  Tertiary alcohols are themselves widely used as solvents or as raw materials for various compounds, and in particular, as synthetic raw materials for (meth) acrylic acid esters. (Meth) acrylic acid esters are used in various fields because of their ease of compositional composition with various monomers, but in recent years the use of resist materials for electronics as synthetic raw materials has increased in the semiconductor manufacturing field. ing. In the pattern transfer process, which is the first process of manufacturing microprocessors, DRAMs, and other semiconductors, an electronic resist material is applied onto a semiconductor substrate, and a fine circuit pattern is formed by monochromatic light or an electron beam that is irradiated through a photomask. Is transferred (exposed). Fine circuits formed through subsequent development, plasma etching, resist removal and other processes are formed with a very narrow and dense line width. Therefore, contamination of impurities, especially metal components, is a short circuit. Can cause problems. If there is a defect in one part of a circuit composed of a large number of integrated transistors, the semiconductor product becomes defective and directly leads to a decrease in the yield of the product. Therefore, in semiconductor manufacturing, it is mixed throughout the entire process. Efforts are constantly being made to reduce impurities.

  For this reason, the reduction of impurities is also strongly required for resists for electronics and resist monomers as raw materials thereof, and particularly, the metal content is required to be reduced to the ppb order level. On the other hand, among metals that can be mixed into the resist monomer, alkali metals such as sodium and potassium, alkaline earth metals such as calcium and magnesium, iron, zinc, and copper are distilled from resist monomers, or nitric acid and oxalic acid. It is effectively removed by acid washing with a chelating agent or the like.

  However, in resist monomers such as (meth) acrylic acid esters manufactured through a manufacturing process using an organometallic compound, lead inevitably mixed in the organometallic compound, or lead presumed to be an organic lead compound Since it contains a compound, it distills simultaneously with the resist monomer even if it is distilled, and it cannot be removed effectively by acid cleaning. Even if it can be considerably removed by repeated purification by these methods, the resist monomer product must be very expensive due to a significant decrease in yield and an increase in cost due to an increase in the process. For this reason, such a resist monomer has a problem that it cannot actually be used as a resist for electronics.

  On the other hand, a method of reducing the lead content in the resist monomer by bringing a resist monomer containing lead or a lead compound as an impurity into contact with chlorine, bromine or iodine has been proposed (see Patent Document 1). According to this method, it is described that the lead content in a resist monomer containing 105 ppb of lead can be reduced to a concentration of 3 to 9 ppb. However, resist monomers are inherently rich in reactivity, and particularly easily react with chlorine, bromine or iodine used in light, and when the reaction occurs, the quality of the resist monomer is lowered. For this reason, the treatment with chlorine or the like for reducing lead has to be performed under light shielding, which is inconvenient in process management and still has a concern about the quality deterioration of the resist monomer.

On the other hand, tertiary alcohol, which is a raw material for synthesizing (meth) acrylic acid ester, has a typical production method based on the reaction of an organometallic compound and a ketone, and is industrially mass-produced by this method. . A typical example of the organometallic compound is a Grignard reagent that is an organomagnesium compound (see, for example, Non-Patent Documents 1 and 2). However, trace metal components such as lead or organic lead compounds are inevitably mixed in the Grignard reagent. Since it is extremely difficult to remove this, the Grignard reagent is used as it is, but as a result, the trace alcohol components are also mixed in the tertiary alcohol produced, which is still distilled, acid washed, chelating agent. It was difficult to remove by ordinary means such as washing with the use of.
JP 2003-128630 A Org. Synth. II, 602 (1943) Org. Synth. II, 402 (1943)

  Under the background described above, the present inventor has found that a mixture of lead and / or a lead compound (hereinafter also referred to as “lead” or the like) in a monomer (meth) acrylate in a resist for electronics is (meta. ) If it is derived from lead mixed in the tertiary alcohol used in the production of acrylic acid and a tertiary alcohol substantially free of lead as an impurity can be produced, it will be synthesized from this. We focused on solving the problem of lead contamination in electronics resist monomers. That is, an object of the present invention is to provide a method for producing a tertiary alcohol in which the content of lead or the like as an impurity is reduced to a level of several ppb.

  As a result of repeated studies for the above-mentioned purpose, the present inventor produced a tertiary alcohol by a Grignard reaction of a ketone, and brought it into contact with halogen in an organic solvent to react with lead (or a lead compound). The present inventors have found that a tertiary alcohol having a reduced lead (or lead compound) content of several ppb can be obtained by removing it from the system and washing away excess halogen, thereby completing the present invention.

That is, the present invention provides the following.
(1) A crude tertiary alcohol containing lead and / or a lead compound as an impurity, a halogen selected from the group consisting of iodine, bromine and chlorine in a mole number equal to or greater than the mole number of the impurity in terms of lead After making it contact, the manufacturing method of the tertiary alcohol including wash | cleaning with water or aqueous solution.
(2) The production method according to 1 above, wherein the contact with the halogen is by mixing the crude tertiary alcohol and an aqueous solution containing a halogen.
(3) The method according to 1 or 2 above, wherein the crude tertiary alcohol is brought into contact with the halogen in a state dissolved in an organic solvent.
(4) The production method according to 3 above, wherein the halogen-containing aqueous solution is produced by a reaction between an alkali metal salt of monooxohalogenic acid and an acid in the aqueous solution.
(5) The method according to any one of 1 to 4 above, wherein the washing includes washing with an aqueous solution containing a reducing agent capable of reducing the halogen to a corresponding halogen ion.
(6) The production method according to any one of 1 to 5 above, wherein the crude tertiary alcohol is produced by a reaction between a ketone and a Grignard reagent.

  According to the present invention, it is possible to produce a tertiary alcohol in which lead and / or lead compounds are reduced to several ppb level. The tertiary alcohol thus obtained can further reduce the impurity content (ppb) in the monomer of the electronic resist synthesized using the tertiary alcohol. In addition, since tertiary alcohol is more stable than resist monomers such as (meth) acrylic acid esters, the treatment for removing lead and / or lead compounds causes deterioration of the quality of the resist monomer. There is no fear.

  In the present invention, the crude tertiary alcohol is obtained by a reaction (Grignard reaction) of an organometallic compound containing lead as an impurity, such as a Grignard reagent, with a ketone. That is, it can be obtained by reacting an organometallic compound corresponding to any hydrocarbon group bonded to the carbon at the 1-position of a tertiary alcohol with a ketone having an oxo group (═O) on the same carbon. it can. The reaction conditions and other details are well known to those skilled in the art.

In the present invention, the tertiary alcohol is not particularly limited except that it is produced by a reaction with an organometallic compound such as a Grignard reagent. Particularly useful for the purposes of the present invention are tertiary alcohols having 4 to 15 carbon atoms, but other alcohols may be used. Such a tertiary alcohol may have not only a straight chain but also a cyclic hydrocarbon moiety, and may have an aromatic ring such as a benzene ring or a naphthalene ring. Further, the tertiary alcohol includes those further having a substituent such as a hydroxyl group. Examples of typical tertiary alcohol in the present invention, 1-ethyl-cyclopentanol, 1-methyl cyclopentanol, 1-ethyl-cyclohexanol, 1-methylcyclohexanol, 1-propyl Le cyclohexanol, 1- Unsubstituted such as propylcyclopentanol, 2-methyl-2-adamantanol, 2-ethyl-2-adamantanol, tert-butanol, 1,1-diethyl-1-propanol, 1,1-dimethyl-1-propanol 2-phenyl-2-propanol, 3-phenyl-3-pentanol, 2-phenyl-2-butanol, 2-methyl-1-phenyl-2-propanol, 2-methyl-1-phenyl-2- Butanol, 3-benzyl-3-hexanol, 2-α-naphthyl-2-propanol, 2 An unsubstituted aromatic ring-containing tertiary alcohol such as methyl-1-β-naphthyl-2-propanol; and a hydroxyl group such as 2-hydroxy-1,1-dimethylethanol and 2-hydroxy-1,1-dimethylpropanol Substituted alkanols; 1-hydroxy-2-phenyl-2-propanol, 1-hydroxy-3-phenyl-3-pentanol, 1-hydroxy-2-phenyl-2-butanol, 1-hydroxy-2-methyl- 3-phenyl-2-propanol, 1-hydroxy-2-methyl-3-phenyl-2-butanol, 1-hydroxy-3-benzyl-3-hexanol, 1-hydroxy-2-α-naphthyl-2-propanol, 2-hydroxymethyl-1-β-naphthyl-2-propanol or the like substituted with a hydroxyl group Ring-containing tertiary alcohols include, but are not limited to.

  In the present invention, the “lead compound” includes organic and inorganic compounds having lead as a constituent element. Regarding the content of lead and / or lead compounds as impurities, “the number of moles of impurities in terms of lead” means the sum of the number of moles of lead atoms contained in lead and / or lead compounds as impurities. Say.

In the present invention, the halogen is selected from iodine, bromine or chlorine. Any of these can be used, but chlorine is particularly preferable from the viewpoint of handling convenience. In the present invention, the term “number of moles” for halogen means the number of moles in terms of a molecule (X ₂ ) composed of two halogen atoms.

  Lead halide is produced by contact between a crude tertiary alcohol containing lead and / or a lead compound as an impurity and halogen, and this may be separated and removed from the tertiary alcohol. The formation of lead halide occurs substantially stoichiometrically (1: 1) with lead and / or lead compounds. Therefore, the amount of halogen to be contacted should be equimolar with the amount of lead and / or lead compound as an impurity (lead conversion). However, in order to speed up the reaction, a larger amount of halogen may be set as appropriate, and this is preferable.

  Halogen may be added in any state of gas (chlorine gas), liquid (bromine), solution (for example, bromine water, iodine aqueous solution), or solid (iodine). From the viewpoint of processing efficiency and convenience of handling, it is preferable to add as gas or liquid, and more preferable to add as liquid. When an aqueous solution is used, it may be a saturated aqueous solution or a relatively dilute unsaturated aqueous solution, but a higher concentration enables faster processing. There is no particular limitation between the amount of the crude tertiary alcohol solution (the total amount when dissolved in an organic solvent) and the amount of the halogen-containing aqueous solution to be brought into contact with it, and it is easy to handle. The liquid volume may be used. Usually, the ratio of the liquid amounts is preferably in the range of 1:10 to 10: 1. The halogen concentration in the halogen aqueous solution may be determined according to the amount of the aqueous solution and the number of moles of halogen to be brought into contact with the number of moles of lead and / or lead compound. The contact between the crude tertiary alcohol and the halogen may be performed at room temperature.

  The amount of lead and / or lead compound (lead conversion) contained in the crude tertiary alcohol to be brought into contact with the halogen is determined by inductively coupled plasma mass spectrometry (ICP-MS) and other persons skilled in the art. It can be measured using an appropriate analysis method known in the art.

When the crude tertiary alcohol is brought into contact with the aqueous halogen solution, the aqueous solution may be prepared by an appropriate method. For example, the halogen may be dissolved as it is in water ( partially monooxohalogenic acid ( HXO ) is formed by an equilibrium reaction in an aqueous solution), and it is liberated from a halogen-containing compound in water. Also good. In the latter case, the halogen-containing compound can be produced, for example, by adding an acid to an aqueous solution of an alkali metal salt of monooxohalogenic acid. From the convenience of handling, alkali metal salts such as sodium salt and potassium salt of monooxohalogenic acid (hypoiousous acid, hypobromous acid, hypochlorous acid), hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid and other Monooxohalogenic acid can be liberated by adding an acid, preferably a strong acid, from which a halogen can be generated by an equilibrium reaction. As the acid, either inorganic or organic can be used.

  When the crude tertiary alcohol is brought into contact with the halogen, the crude tertiary alcohol can be reacted in a state dissolved in an organic solvent. The organic solvent only needs to be substantially non-reactive with the halogen used, and may be an organic solvent miscible with water or an immiscible organic solvent. Examples of organic solvents include octane, heptane, hexane, cyclohexane and other aliphatic hydrocarbons, tetrachloromethane, chloroform, dichloroethane and other halogenated hydrocarbons, benzene, toluene, xylene and other aromatic hydrocarbons, ethyl acetate, Examples include, but are not limited to, propyl acetate, butyl acetate, isobutyl acetate and other esters, ethyl ether, propyl ether, 1,4-dioxane, tetrahydrofuran and other ethers.

  The reaction mixture is washed with water or an aqueous solution. In this case, if applicable, the solvent may be exchanged from a water-miscible organic solvent to an immiscible organic solvent. The lead halide formed in the reaction mixture is easily removed by washing with water or an aqueous solution. The excess of halogen used in contact with the halogen usually remains. The method for removing this is not particularly limited, and various methods known to those skilled in the art can be used. For example, the washing with water may be repeated to dissolve and remove the remaining halogen in water, or the remaining halogen may be washed and removed after being reduced to the form of halogen ions. The latter is more efficient and preferable. In order to reduce the residual halogen to a halogen ion, it may be appropriately selected from reducing agents known to those skilled in the art to have a reducing power having a strength necessary for this and added to water. Examples of such a reducing agent include, but are not limited to, sodium thiosulfate and sodium nithionite.

  By the method of the present invention, a crude tertiary alcohol can be purified to a tertiary alcohol having a lead content reduced to several ppb or less. In this specification, the term “several ppb or less” refers to a concentration of 10 ppb or less, particularly preferably 5 ppb or less, and more preferably 3 ppb or less.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not intended to be limited to the examples.

[Example 1]
Metal magnesium 118g ethyl chloride 365.3G, a tetrahydrofuran solution 1570g chloride an ethyl magnesium adjusted to a concentration of 3.0 mol / kg, under a nitrogen atmosphere, the sample inlet, equipped with a condenser, a thermometer and a stirrer A 3 L glass flask was charged. Further, 190 g of tetrahydrofuran was added and the mixture was cooled with stirring. After reaching 10 ° C. or lower, 370 g of cyclopentanone was slowly added dropwise so that the temperature in the kettle did not exceed 40 ° C., and aging was performed until the conversion rate reached 98% at the same temperature. After confirming the completion of the reaction by gas chromatography, it was cooled to 20 ° C.

  Subsequently, 870 g of water was charged in a 5 L glass flask previously equipped with a cooler, a thermometer, a pH meter, a dropping device, and a stirrer, and sufficiently cooled. The previous reaction mixture and 503 g of 35% hydrochloric acid were simultaneously added dropwise to the vessel while maintaining the pH of 3 to 6 at a temperature of 40 ° C. or less. After dripping the whole quantity, it left still and isolate | separated the lower layer. The upper layer was neutralized and washed with potassium carbonate, and tetrahydrofuran was distilled off under reduced pressure.

  The obtained crude tertiary alcohol was dissolved in 1500 g of n-hexane, and washed with 2500 g of a 0.6% aqueous sodium hypochlorite solution and 20 g of 35% hydrochloric acid. Next, the upper layer (organic layer) was washed with 2000 g of 1% sodium thiosulfate, and then washed in the order of oxalic acid, brine, and sodium bicarbonate water.

  The washed organic layer was transferred to a container equipped with a distillation tower and 0.5 g of potassium carbonate powder was added. N-Hexane was distilled off under reduced pressure, followed by distillation to obtain 278 g of 1-ethylcyclopentanol. When this was measured by ICP-MS, the content of the lead component was 2 ppb.

[Example 2]
In the same manner as in Example 1, operation was performed using cyclohexanone instead of cyclopentanone to obtain 1-ethylcyclohexanol. When this was measured by ICP-MS, the content of the lead component was 3 ppb.

[Comparative Example 1]
In the same manner as in Example 1, after the reaction between ethylmagnesium chloride and cyclopentanone and neutralization washing with potassium carbonate, the reaction mixture was transferred to a vessel equipped with a distillation column, and 0.5 g of potassium carbonate powder was added. Tetrahydrofuran was distilled off under reduced pressure, followed by distillation to obtain 1-ethylcyclopentanol. When this was measured by ICP-MS, the content of the lead component was 501 ppb.

[Comparative Example 2]
In the same manner as in Example 2, after the reaction between ethylmagnesium chloride and cyclohexanone and neutralization washing with potassium carbonate, 1-ethylcyclohexanol was obtained in the same manner as in Comparative Example 1. This was measured by ICP-M S, lead content component was 393Ppb.

[Reference Example 1]
Using the tertiary alcohol obtained in Example 1, 1-ethylcyclopentyl acrylate was synthesized by a conventional method and measured by ICP-MS. As a result, the content of the lead component was 1 ppb.

[Reference Example 2]
Using the crude tertiary alcohol obtained in Comparative Example 1, 1-ethylcyclopentyl acrylate was synthesized by a conventional method and measured by ICP-MS. As a result, the content of the lead component was 286 ppb.

[Reference Example 3]
Using the tertiary alcohol obtained in Example 2, 1-ethylcyclohexyl methacrylate was synthesized by a conventional method and measured by ICP-MS. As a result, the content of the lead component was 1 ppb.

[Reference Example 4]
Using the crude tertiary alcohol obtained in Comparative Example 2, 1-ethylcyclohexyl methacrylate was synthesized by a conventional method and measured by ICP-MS. As a result, the content of the lead component was 147 ppb.

  The above results show that according to the present invention, the content of lead (or lead compound) in tertiary alcohol obtained through a reaction using an organometallic compound such as a Grignard reagent can be extremely reduced. As a result, it is shown that the content of lead (or lead compound) in the (meth) acrylic acid ester obtained by using this can be further reduced.

The present invention can be used to produce tertiary alcohols that are based on the Grignard reaction and have very low lead (or lead compound) contamination, and as a result, lead purity that sufficiently satisfies the requirements in semiconductor manufacturing. It can be used to supply raw materials for the production of high-purity monomers that give resist.

Claims (6)

Including contacting a tertiary alcohol containing lead as an impurity with a halogen selected from the group consisting of iodine, bromine and chlorine in a mole number equal to or greater than the number of moles of lead atoms , and then washing with water or an aqueous solution. A method for producing a tertiary alcohol having a reduced lead content , wherein the tertiary alcohol is 1-ethylcyclopentanol, 1-methylcyclopentanol, 1-ethylcyclohexanol, 1-methylcyclohexanol 1-propylcyclohexanol, 1-propylcyclopentanol, 2-methyl-2-adamantanol, 2-ethyl-2-adamantanol, tert-butanol, 1,1-diethyl-1-propanol, 1,1- Dimethyl-1-propanol; 2-phenyl-2-propanol, 3-phenyl-3-pentanol, 2-phenyl 2-butanol, 2-methyl-1-phenyl-2-propanol, 2-methyl-1-phenyl-2-butanol, 3-benzyl-3-hexanol, 2-α-naphthyl-2-propanol, 2-methyl -1-β-naphthyl-2-propanol; 2-hydroxy-1,1-dimethylethanol, 2-hydroxy-1,1-dimethylpropanol; 1-hydroxy-2-phenyl-2-propanol, 1-hydroxy-3 -Phenyl-3-pentanol, 1-hydroxy-2-phenyl-2-butanol, 1-hydroxy-2-methyl-3-phenyl-2-propanol, 1-hydroxy-2-methyl-3-phenyl-2- Butanol, 1-hydroxy-3-benzyl-3-hexanol, 1-hydroxy-2-α-naphthyl-2-propanol Beauty are those selected from the group consisting of 2-hydroxymethyl--1-beta-naphthyl-2-propanol method. The process according to claim 1, wherein the contact with the halogen is by mixing a tertiary alcohol containing lead as the impurity and an aqueous solution containing halogen in the form of monooxohalogenic acid . A tertiary alcohol containing lead as the impurity is octane, heptane, hexane, cyclohexane, tetrachloromethane, chloroform, dichloroethane, benzene, toluene, xylene, ethyl acetate, propyl acetate, butyl acetate, isobutyl acetate, ethyl ether, The manufacturing method of Claim 1 or 2 which makes it contact with this halogen in the state melt | dissolved in the organic solvent chosen from the group which consists of a propyl ether, a 1, 4- dioxane, and tetrahydrofuran . The aqueous solution containing the halogen is produced by a reaction of hypoiodic acid, hypobromous acid or hypochlorous acid alkali metal salt with hydrochloric acid, sulfuric acid, nitric acid or phosphoric acid in the aqueous solution. Item 3. The production method according to Item 2 . It said cleaning state, and are not a wash with an aqueous solution containing a reducing agent capable of reducing to a halide ion corresponding to the halogen, selected from the group reducing agent is made of sodium thiosulfate and sodium dithionite it is those, either manufacturing method of claims 1 to 4. 6. The production method according to claim 1, wherein the tertiary alcohol containing lead as an impurity is produced by a reaction between a ketone and a Grignard reagent.