JP2017178808A - Method for manufacturing trans-1,4-cyclohexanedicarboxylic acid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple method for manufacturing trans-1,4-cyclohexanedicarboxylic acid from 1,4,-cyclohexanedicarboxylic acid at high purity and high yield.SOLUTION: A manufacturing method includes isomerizing 1,4-cyclohexanedicarboxylic acid into trans-1,4-cyclohexanedicarboxylic acid by heating 1,4-cyclohexanedicarboxylic acid in a non proton-based polar solvent in the presence of a basic compound.SELECTED DRAWING: None

Description

The present invention relates to a process for producing trans-1,4-cyclohexanedicarboxylic acid.

Trans-1,4-cyclohexanedicarboxylic acid (hereinafter referred to as “t-CHDA”) is a useful compound as a raw material for pharmaceuticals, synthetic resins, synthetic fibers, and liquid crystal materials.

At present, 1,4-cyclohexanedicarboxylic acid (hereinafter referred to as “CHDA”) is (1) a method in which terephthalate is hydrogenated and then neutralized, and (2) terephthalate is hydrogenated and then hydrolyzed. It is manufactured by the method.

The CHDA obtained by the above method is usually a mixture of cis-1,4-cyclohexanedicarboxylic acid (hereinafter referred to as “c-CHDA”) 60 to 80% and t-CHDA 20 to 40%. .

As a method for obtaining high-purity t-CHDA from CHDA, c-CHDA is heated in a solvent and thermally isomerized to t-CHDA (Patent Documents 1 and 2), c-CHDA and t-CHDA, A method of selectively separating only t-CHDA using the difference in melting point (Patent Document 3), and only t-CHDA using the difference in easiness of forming a salt between c-CHDA and t-CHDA. A method for selectively separating the two is known (Patent Document 4).

In Patent Document 1, since the isomerization reaction is performed at a high temperature of 240 ° C., it is extremely difficult in terms of apparatus and operation, and the obtained t-CHDA has a purity as low as 99.0% or less. There was a problem.

In Patent Document 2, since the isomerization reaction is performed in an aqueous solution at a high temperature of 320 ° C. and a high pressure, there is a problem that it is very difficult in terms of the apparatus and operation.

In Patent Document 3, it is necessary to perform the operation at a high temperature of 230 ° C. or higher, which is very difficult in terms of the apparatus and operation, and the t-CHDA obtained has a purity of 97.0% or less. There was a problem of low.

In Patent Document 4, since there is no isomerization reaction, there is a problem that the yield of t-CHDA is low when the trans-isomer content of CHDA is small.

JP 2008-063311 A JP-A 56-120636 JP 2004-043426 A JP 2002-363126 A

As described above, the method of obtaining t-CHDA from CHDA requires an anti-corrosion device and a high-pressure device on the device side in order to carry out the isomerization reaction at a high temperature, and also requires a complicated operation on the operation surface. Therefore, there is a problem that the production cost is high, and there is a problem that the purity of the obtained t-CHDA is low.

Further, in the method of obtaining t-CHDA from CHDA, when no isomerization reaction is involved, there is a problem that the yield of t-CHDA is reduced if the content of t-CHDA in the raw material CHDA is small.

The present invention has been invented to solve the above-mentioned problems, and an object of the present invention is to provide a method for easily producing t-CHDA with high purity and high yield.

As a result of intensive studies to achieve the above-mentioned problems, the present inventor has a step of isomerizing CHDA into t-CHDA by heating in the presence of a basic compound in an aprotic polar solvent, The inventors have found that t-CHDA can be obtained with high purity and high yield, and have completed the present invention.

That is, the present invention is as follows.

[Claim 1]
A step of isomerizing 1,4-cyclohexanedicarboxylic acid containing cis-1,4-cyclohexanedicarboxylic acid into a trans isomer by heating in the presence of a basic compound in an aprotic polar solvent; A process for producing trans-1,4-cyclohexanedicarboxylic acid.

[Section 2]
Aprotic polar solvents are dimethyl sulfoxide, sulfolane, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-dimethylpropionic acid amide, N, N-dimethylbutyric acid amide, N, N-dimethylisobutyric acid amide And at least one aprotic polar solvent selected from the group consisting of N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone and 1,3-dimethyl-2-imidazolidinone [Item 1] The manufacturing method as described in.

[Section 3]
[Claim 1] wherein the basic compound is at least one basic compound selected from the group consisting of Group 1A or 2A group hydroxides, carbonates and acetates, and tertiary amine compounds of the periodic table. The production method according to [Item 2].

[Claim 4]
The hydroxide of group 1A or 2A of the periodic table is at least one hydroxide selected from the group consisting of lithium hydroxide, sodium hydroxide, potassium hydroxide, magnesium hydroxide and calcium hydroxide. 3].

[Section 5]
The production method according to [Item 3], wherein the carbonate of Group 1A or Group 2A of the periodic table is at least one carbonate selected from the group consisting of lithium carbonate, sodium carbonate, potassium carbonate, magnesium carbonate, and calcium carbonate. .

[Claim 6]
The production method according to [Item 3], wherein the acetate of Group 1A or Group 2A of the periodic table is at least one acetate selected from the group consisting of lithium acetate, sodium acetate, potassium acetate, magnesium acetate, and calcium acetate. .

[Claim 7]
The tertiary amine compound is at least one selected from the group consisting of trimethylamine, methyldiethylamine, triethylamine, dimethylcyclohexylamine, dimethyloctylamine, dimethyldecylamine, dimethyldodecylamine, dimethylbenzylamine, diethylhexylamine and didodecylmethylamine. The production method according to [Item 3], which is a seed tertiary amine compound.

[Section 8]
The production method according to any one of [Item 1] to [Item 7], wherein the basic compound is 0.5 to 5 parts by weight with respect to 100 parts by weight of 1,4-cyclohexanedicarboxylic acid.

[Claim 9]
The production method according to any one of [Item 1] to [Item 4], wherein 1,4-cyclohexanedicarboxylic acid is 10 to 230 parts by weight with respect to 100 parts by weight of the aprotic polar solvent.

[Section 10]
The production method according to any one of [Item 1] to [Item 9], wherein the isomerization temperature is 150 to 200 ° C.

By the production method of the present invention, t-CHDA can be produced from CHDA with high purity and high yield, and can be produced simply. The isomerization reaction according to this production method is a relatively mild reaction condition and is a simple operation, and thus can be produced without requiring an expensive reaction apparatus. Moreover, since t-CHDA which concerns on this invention is high purity, it can be used as a raw material of a pharmaceutical, a synthetic resin, a synthetic fiber, and a liquid crystal material.

In the method for producing t-CHDA of the present invention, CHDA containing c-CHDA is heated in the presence of a basic compound in an aprotic polar solvent to thereby convert the contained c-CHDA into t-CHDA. It is a production method characterized by isomerization.

CHDA can be a commercially available product, a reagent, or one prepared by a known synthesis method. For example, as a known synthesis method of CHDA, a method of producing a neutralized terephthalic acid sodium salt after hydrogenation, or hydrogenating a terephthalic acid ester to form 1,4-cyclohexanedicarboxylic acid ester, followed by hydrolysis. The method of manufacturing is illustrated.

The ratio of c-CHDA and t-CHDA in CHDA obtained by the above production method is usually in the range of 80:20 to 60:40.

Specific examples of aprotic polar solvents include dimethyl sulfoxide, sulfolane, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-dimethylpropionic acid amide, N, N-dimethylbutyric acid amide, N, N -Dimethylisobutyric acid amide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like. Among these, N-methyl-2-pyrrolidone and 1,3-dimethyl-2-imidazolidinone are preferable, and N-methyl-2-pyrrolidone is particularly preferable.

Each of the above aprotic polar solvents can be used alone or in combination of two or more.

Examples of basic compounds include 1A or 2A group hydroxides, carbonates and acetates, and tertiary amine compounds of the periodic table.

Specific examples of the Group 1A or 2A group hydroxides include lithium hydroxide, sodium hydroxide, potassium hydroxide, magnesium hydroxide, and calcium hydroxide. Among these, sodium hydroxide and potassium hydroxide are preferable.

Specific examples of the Group 1A or 2A Group carbonates include lithium carbonate, sodium carbonate, potassium carbonate, magnesium carbonate, and calcium carbonate. Among these, sodium carbonate and potassium carbonate are preferable.

Specific examples of the periodic table Group 1A or Group 2A acetates include lithium acetate, sodium acetate, potassium acetate, magnesium acetate, and calcium acetate. Among these, sodium acetate and potassium acetate are preferable.

Specific examples of the tertiary amine compound include trimethylamine, methyldiethylamine, triethylamine, dimethylcyclohexylamine, dimethyloctylamine, dimethyldecylamine, dimethyldodecylamine, dimethylbenzylamine, diethylhexylamine and didodecylmethylamine. Among these, triethylamine is preferable.

The above basic compounds can be used alone or in combination of two or more.

0.5-5 weight part is preferable with respect to 100 weight part of CHDA, and, as for a basic compound, 0.5-3 weight part is especially preferable. If the amount used is less than 0.5 parts by weight, the isomerization rate tends to be slow, and even if it is used more than 5 parts by weight, it is difficult to obtain the effect of increasing the isomerization rate commensurate with the amount used.

CHDA is preferably 10 to 230 parts by weight, more preferably 30 to 150 parts by weight, and particularly preferably 45 to 100 parts by weight with respect to 100 parts by weight of the aprotic polar solvent. If the amount is less than 10 parts by weight, the production cost may be increased, which is economically disadvantageous. If the amount is more than 230 parts by weight, CHDA does not completely dissolve and the isomerization rate tends to decrease.

The isomerization reaction temperature is preferably in the range of 150 to 200 ° C, particularly preferably in the range of 170 to 200 ° C. When the reaction temperature is lower than 150 ° C., the isomerization rate tends to be slow. When the reaction temperature is higher than 200 ° C., the aprotic polar solvent is colored, and as a result, the target t-CHDA is easily colored. In addition, on the device side, a corrosion-resistant device or a high-pressure device may be required, and since a complicated operation may be required on the operation surface, the manufacturing cost may increase. It may be economically disadvantageous.

The isomerization reaction time is usually about 2 to 10 hours, preferably about 3 to 8 hours.

The isomerization reaction is preferably performed in an inert atmosphere from the viewpoint of safety and prevention of coloring of the aprotic polar solvent. The inert atmosphere means the presence of a gas (inert gas) that does not substantially react with CHDA under the isomerization reaction conditions of the present invention. Although it does not specifically limit as an inert gas, For example, it is a carbon dioxide, nitrogen, argon, or these arbitrary gas mixtures etc., and nitrogen is especially preferable for implementing industrially.

After the isomerization reaction, t-CHDA can be preferentially precipitated from the reaction solution by lowering the temperature of the reaction solution after the concentration or solvent is distilled off to adjust to a predetermined CHDA concentration. The predetermined CHAD concentration is preferably about 30 to 70% by weight. Although the rate of temperature reduction is not particularly limited, for example, cooling to room temperature at a rate of preferably 10 to 50 ° C./hr can be mentioned. The precipitated t-CHDA crystals can be separated by a method such as filtration. The separated crystals may be dried as they are, and it is recommended that the crystals be rinsed with an aprotic polar solvent or water and then dried.

The drying method is not particularly limited, but can be performed with an atmospheric shelf dryer, a vacuum shelf dryer, a container rotary vacuum dryer, or the like. Heating under reduced pressure and drying are preferred, and a method of heating under reduced pressure and rotating t-CHDA is particularly preferred. Examples of drying conditions include 0.13 to 1.33 kPa as a decompression condition and 100 to 200 ° C. as a drying temperature.

By the production method of the present invention, highly pure t-CHDA can be easily obtained, and t-CHDA having a purity of 99.0% or more can also be obtained.

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. Measurement methods in Examples and Comparative Examples are as follows. Further, reagents were used for the compounds not particularly mentioned.

<CHDA isomer ratio (c / t) and t-CHDA purity (GC area%)>
The CHDA isomer ratio (c / t) and t-CHDA purity (GC area%) in Examples and Comparative Examples were determined as follows. CHDA was converted to silyl ester (hereinafter abbreviated as CHDA silyl ester). Thereafter, gas chromatography (GC) analysis was performed to obtain CHDA silyl ester by area percentage method, and the corresponding values were used as CHDA isomer ratio (c / t) and t-CHDA (GC area%). . The order of the peaks of the CHDA silyl ester is c-CHDA and t-CHDA in order of decreasing retention time.

(Sample preparation of CHDA silyl ester)
30 mg of CHDA was collected and dissolved in 500 mg of pyridine, and at room temperature, BSTFA-TMCS (N, O-bis (trimethylsilyl) trifluoroacetamido-trimethylchlorosilane [99: 1], Tokyo Chemical Industry Co., Ltd.) was used as a trimethylsilylating agent. CHDA silyl ester was prepared.

(GC analysis conditions)
Device: GC-2010 Plus, manufactured by Shimadzu Corporation
Column: TC-5 (column length: 30 m, column inner diameter: 0.25 mm, film thickness: 0.25 μm, manufactured by GL Science)
Carrier gas: Helium (40 cm / sec, constant linear velocity)
Split ratio: 1/50
Injection temperature: 300 ° C
Detector: FID (325 ° C)
Injection volume: 1.5 μL
Column temperature program: 100 ° C. (2 minutes hold) to (temperature rise 10 ° C./min) to 320 ° C. (1 minute hold)

<Metal analysis (ICP emission spectroscopy)>
Device: iCAP6500Duo (Thermo Fisher SCIENTIFIC)
Metal analysis was performed by pretreatment by microwave decomposition method. Pretreatment was performed using an apparatus: Multiwave PRO (manufactured by Anton Paar), 0.2 g of a sample and 6 ml of special grade nitric acid were added, decomposed with a microwave decomposing apparatus, and about 15 g with distilled water. Thereafter, metal analysis was performed using an ICP emission spectroscopic analyzer.

[Example 1]
A 500 ml reactor (made of glass) equipped with a thermometer, a condenser, and a stirrer was charged with 60.0 g of CHDA (manufactured by Shin Nippon Chemical Co., Ltd., product name “Ricacid CHDA”, c-CHDA / t-CHDA = 75/25) 1.5 g of sodium hydroxide was added to 140.0 g of N-methyl-2-pyrrolidone (NMP) as a protonic polar solvent (reaction solvent), and the temperature was raised to 180 ° C. with stirring. The mixture was stirred for 7 hours while maintaining 180 ° C. The ratio of CHDA isomers when the reaction was stopped was analyzed by GC. Thereafter, the mixture was cooled to room temperature at a temperature drop rate of about 10 ° C./hr, and the precipitated crystals were filtered out under reduced pressure. The obtained wet crystals were dried under reduced pressure (170 ° C./3 hours / 0.27 kPa) to obtain 27.4 g of t-CHDA (yield 45.7% from CHDA). As a result of conducting a metal analysis of the obtained t-CHDA, sodium was 29 ppm. The reaction conditions are shown in Table 1, and the results of GC analysis of the obtained t-CHDA are shown in Table 2.

[Example 2]
The same procedure as in Example 1 was carried out except that 2.1 g of potassium hydroxide was used instead of 1.5 g of sodium hydroxide to obtain 25.8 g of t-CHDA (43.0% yield from CHDA). As a result of conducting a metal analysis of the obtained t-CHDA, potassium was 90 ppm. The reaction conditions are shown in Table 1, and the results of GC analysis of the obtained t-CHDA are shown in Table 2.

[Example 3]
Except for using 100.0 g of CHDA and 100.0 g of N-methyl-2-pyrrolidone, the same procedure as in Example 1 was carried out to obtain 50.0 g of t-CHDA (yield 50.0% from CHDA). As a result of conducting a metal analysis of the obtained t-CHDA, sodium was 43 ppm. The reaction conditions are shown in Table 1, and the results of GC analysis of the obtained t-CHDA are shown in Table 2.

[Example 4]
Except that 100.0 g of CHDA, 100.0 g of N-methyl-2-pyrrolidone and 2.1 g of potassium hydroxide were used, the same procedure as in Example 1 was carried out, and 51.4 g of t-CHDA (yield from CHDA: 51.4% ) As a result of conducting a metal analysis of the obtained t-CHDA, potassium was 105 ppm. The reaction conditions are shown in Table 1, and the results of GC analysis of the obtained t-CHDA are shown in Table 2.

[Comparative Example 1]
Except not adding 1.5 g of sodium hydroxide, it carried out like Example 1 and obtained CHDA15.9g (yield 26.5% from CHDA). The reaction conditions are shown in Table 1, and the results of GC analysis of the obtained CHDA are shown in Table 2.

[Comparative Example 2]
The reaction was conducted in the same manner as in Example 1 except that the reaction temperature was 130 ° C., to obtain 19.8 g of CHDA (yield 33.0% from CHDA). As a result of conducting a metal analysis of the obtained t-CHDA, sodium was 54 ppm. The reaction conditions are shown in Table 1, and the results of GC analysis of the obtained CHDA are shown in Table 2.

[Comparative Example 3]
Except not adding 1.5 g of sodium hydroxide, it carried out like Example 3 and obtained CHDA 31.5g (yield 31.5% from CHDA). The reaction conditions are shown in Table 1, and the results of GC analysis of the obtained CHDA are shown in Table 2.

From Table 1 and Table 2, it is clear that according to the production method of the present invention, high yield and high purity t-CHDA can be obtained.

Since t-CHDA obtained by the present invention has high purity, it can be suitably used as a raw material for pharmaceuticals, synthetic resins, synthetic fibers, and liquid crystal materials.

Claims (6)

A step of isomerizing 1,4-cyclohexanedicarboxylic acid containing cis-1,4-cyclohexanedicarboxylic acid into a trans isomer by heating in the presence of a basic compound in an aprotic polar solvent; A process for producing trans-1,4-cyclohexanedicarboxylic acid. Aprotic polar solvents are dimethyl sulfoxide, sulfolane, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-dimethylpropionic acid amide, N, N-dimethylbutyric acid amide, N, N-dimethylisobutyric acid amide And at least one aprotic polar solvent selected from the group consisting of N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone and 1,3-dimethyl-2-imidazolidinone. The manufacturing method as described. The basic compound is at least one basic compound selected from the group consisting of 1A or 2A group hydroxides, carbonates and acetates, and tertiary amine compounds of the periodic table. Item 3. The manufacturing method according to Item 2. The manufacturing method in any one of Claims 1-3 whose basic compound is 0.5-5 weight part with respect to 100 weight part of 1, 4- cyclohexane dicarboxylic acid. The manufacturing method in any one of Claims 1-4 whose 1, 4- cyclohexane dicarboxylic acid is 10-230 weight part with respect to 100 weight part of aprotic polar solvents. The production method according to claim 1, wherein the isomerization temperature is 150 to 200 ° C.