JP2002030029A - Process for producing trans-dicyclohexyl-3,3'4,4'-tetracarboxylic acid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel starting material for polyimide resin, tr
A process for preparing ans-dicyclohexyl-3,3'4,4'-tetracarboxylic acid is provided. SOLUTION: The product obtained by hydrogen reduction of tetramethyl biphenyl-3,3'4,4'-tetracarboxylate is recrystallized to preferentially separate isomers having a cis structure, and this is hydrolyzed. The cis-tetracarboxylic acid obtained by decomposition is heated in water at 200 to 250 ° C. using an autoclave (1R, 1 ′S, 3R, 3 ′S, 4R, 4 ′S). Trans-dicyclohexyl-3,3'4,4'- such as -dicyclohexyl-3,3'4,4'-tetracarboxylic acid
Provided is a method for producing a tetracarboxylic acid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing trans (trans) -dicyclohexyl-3,3′4,4′-tetracarboxylic acid suitable as a polyimide precursor, and more particularly to (1R, 1 ′S, 3R, 3'S, 4
R, 4'S) -Dicyclohexyl-3,3'4,4'-
Tetracarboxylic acid, (1S, 1'S, 3S, 3'S, 4
(S, 4'S) -Dicyclohexyl-3,3'4,4'-
Tetracarboxylic acid, and / or (1R, 1′R, 3
R, 3'R, 4R, 4'R) -Dicyclohexyl-3
Trans consisting of 3'4,4'-tetracarboxylic acid
(Trans) -Dicyclohexyl-3,3'4,4'-
It relates to a method for producing tetracarboxylic acid.

[0002]

2. Description of the Related Art Tetracarboxylic acids are compounds useful as precursors of tetracarboxylic dianhydride, which is a raw material for polyimide resins having excellent heat resistance. The conversion of a benzene ring to the corresponding cyclohexane ring by hydrogen reduction is well known and is described, for example, in a synthetic command.
unication, 25 , 2079 (1995), JP-A-10-36320, JP-A-11-189568.
JP-A-11-349535, JP-A-10-204
No. 002 and Tokuhei 8-30045 have been reported.

[0003] When hydrogen reduction of tetramethyl biphenyl-3,3'4,4'-tetracarboxylate (abbreviated as BPTM), the product has six asymmetric carbons,
^Six isomers are possible. The hydrogen reduction of BPTM is also described in JP-A-7-215912 and JP-A-8-3251.
No. 96 and JP-A-8-325201 have been reported.

[0004]

These reports do not mention this isomer at all, but refer only to mixtures. The present invention has been intensively studied for the purpose of isolating a specific isomer from a mixture of many isomers.

[0005]

According to the present invention, a product obtained by hydrogen reduction of tetramethyl biphenyl-3,3'4,4'-tetracarboxylate is recrystallized to preferentially obtain cis.
Cis obtained by separating the structural isomer and hydrolyzing it
(1R, 1'S, 3R, 3'S, 4R, 4 ') wherein (cis) -tetracarboxylic acid is heated in water using an autoclave at 200 to 250 ° C. S)-
Dicyclohexyl-3,3'4,4'-tetracarboxylic acid (hereinafter sometimes abbreviated as trans-DCTA-1), (1S, 1'S, 3S, 3'S, 4S, 4 '
S) -dicyclohexyl-3,3′4,4′-tetracarboxylic acid (hereinafter sometimes abbreviated as trans-DCTA-2), and / or (1R, 1′R, 3R,
3′R, 4R, 4′R) -Dicyclohexyl-3,3 ′
4,4'-tetracarboxylic acid (hereinafter, trans-DC
TA-3) (which may be abbreviated as TA-3).
The present invention relates to a method for producing dicyclohexyl-3,3'4,4'-tetracarboxylic acid.

The starting material of the present invention (1R, 1 ')
Tetramethyl S, 3R, 3 ′S, 4S, 4′R) -dicyclohexyl-3,3′4,4′-tetracarboxylate (abbreviated as cis-DCTM-x), (1R, 1′R, 3
R, 3′R, 4S, 4 ′S) -Dicyclohexyl-3
Tetramethyl 3'4,4'-tetracarboxylate (cis
-DCTM-y) and (1S, 1'S, 3
S, 3 ′S, 4R, 4′R) -Dicyclohexyl-3
Tetramethyl 3'4,4'-tetracarboxylate (cis
-DCTM-z) has already been filed as Japanese Patent Application No. 2000-191050.

The cis-dicyclohexyl-3,3 '
Preferably, each isomer of tetramethyl 4,4′-tetracarboxylate is obtained by hydrogen reduction of tetramethyl biphenyl-3,3′4,4′-tetracarboxylate (hereinafter sometimes abbreviated as BPTM). The resulting product (DCTM) can be recrystallized to preferentially separate isomers having the cis structure, which can be further obtained by isolating each isomer by a preferential crystallization method.

[0008] A reaction formula for producing an isomer by converting the BPTM into a DCTM by hydrogen reduction is shown below. (Me in the formula
Represents a methyl group. )

Embedded image

The BPTM used as the starting material is
For example, it can be easily synthesized by a method for producing a biphenyl compound by coupling dimethyl phthalate described in JP-B-60-33379 in the presence of oxygen, a palladium salt and 1,10-phenanthroline or bipyridyl.

A known method can be applied to the above-mentioned hydrogen reduction, and as a solvent, methanol, ethanol, butanol or the like can be used.
Ordinary organic solvents such as toluene, ethyl acetate and tetrahydrofuran can be used. The amount of the solvent used is not specified as long as BPTM is sufficiently dissolved, but usually, 10 g of BPT is used.
25 to 100 mL for M.

In the hydrogen reduction, 0.1 to 1 as a catalyst is used.
Ru / C (carbon), Rh / C, Pd supported 0% by weight
/ C, or an alumina carrier or a silica carrier thereof. A catalyst amount of 0.1 to 0.5 g is sufficient for 10 g of BPTM. As reaction conditions,
It proceeds at normal pressure, but in order to increase the speed, it is better to perform it under pressure, 2 to 100 atm, preferably 10 to 50 atm.
Atmospheric pressure is sufficient. The reaction is carried out at a temperature of 50 to 250 ° C, preferably 100 to 200 ° C. 1 to complete the reaction
The reaction is carried out for 10 hours. The reaction is carried out until the absorption of hydrogen is completed, and is usually completed in about 5 hours at 100 ° C.
Although not limited to the reaction method, it is preferable to continuously supply hydrogen.

After removing the catalyst from the reaction solution by an operation such as filtration, the solvent is removed to leave a viscous solid as a product.
From this product mixture, cis-dicyclohexyl-3,
Tetramethyl 3'4,4'-tetracarboxylate (cis
-DCTM) can be obtained by recrystallization in a suitable solvent or distillation under reduced pressure to collect a specific fraction. As a solvent used for the recrystallization, a usual organic solvent such as methanol, ethanol, butanol, ethyl acetate, and tetrahydrofuran can be used. The amount of this product 1
200-1000 mL per 00 g.

At this time, the cis isomer preferentially precipitates. In capillary chromatography (CGC),
Although a single peak is shown, high performance liquid chromatography (H
PLC) showed three peaks when analyzed using a Chiralcel OD column. Therefore, this cis isomer is resolved by the usual preferential crystallization method. As a solvent used for this separation, methanol, ethanol, butanol, ethyl acetate, tetrahydrofuran and the like can be used. The amount used is not limited, but 200 to 500 mL per 100 g
Crystallization can be repeated to a degree to obtain a pure isomer. In order to increase the purity of the crystal, it is preferable to perform crystallization at a temperature of about 20 to 40 ° C. The structure can be ultimately determined from X-ray analysis by growing a single crystal.

The 1R, 1'S, 3R, 3'S, 4S,
The chemical formula of 4′R) -dicyclohexyl-3,3′4,4′-tetramethyltetracarboxylate (cis-DCTM-x) is shown below.

[0015]

Embedded image

Further, (1R, 1'R, 3R, 3'R, 4
(S, 4'S) -Dicyclohexyl-3,3'4,4'-
Tetramethyl tetracarboxylate (cis-DCTM-
y) can be represented by the following chemical formula:

[0017]

Embedded image

Also, (1S, 1'S, 3S, 3'S, 4
R, 4'R) -Dicyclohexyl-3,3'4,4'-
Tetramethyl tetracarboxylate (cis-DCTM-
z) can be represented by the following chemical formula.

[0019]

Embedded image

These cis-DCTMs can be converted to the corresponding cis-tetracarboxylic acids by alkaline or acid hydrolysis. Then, these cis-tetracarboxylic acids can be converted into trans-tetracarboxylic acids by heating in water without a catalyst.

In the present invention, preferably (1R, 1'S,
3R, 3'S, 4S, 4'R) -Dicyclohexyl-
3,3'4,4'-tetracarboxylic acid (cis-DCT
Ax), (1R, 1'R, 3R, 3'R, 4
(S, 4'S) -Dicyclohexyl-3,3'4,4'-
Tetracarboxylic acid (abbreviated as cis-DCTA-y), and (1S, 1'S, 3S, 3'S, 4R, 4'R)-
Dicyclohexyl-3,3′4,4′-tetracarboxylic acid (abbreviated as cis-DCTA-z) was used in an amount of 30 to 100 mL of water per 10 g, and the reaction temperature was set to 200 to 250 ° C.
When heated to a pressure of steam rises to 15 to 40 kg / c
m ² . If the reaction temperature is lower than this, the reaction does not proceed, and if it is higher than this, a decomposition reaction occurs. At this time, although the cause is not clear, conversion of the starting cis-tetracarboxylic acid to trans-tetracarboxylic acid occurs. This is considered to be a reaction unique to the cyclohexane ring system.

The reaction time requires about 1 hour to 10 hours,
After completion of the reaction, trans-DCTA precipitated from water is separated. If the amount of water is small, the purity of the product decreases, and if it is too large, the yield decreases. In particular, although not required, the reaction can be carried out under nitrogen pressure.

According to the present invention, (1R, 1 '
S, 3R, 3'S, 4R, 4'S) -Dicyclohexyl-3,3'4,4'-tetracarboxylic acid (trans-
The chemical formula of DCTA-1) is shown below.

[0024]

Embedded image

(1S, 1 ') obtained by the present invention
S, 3S, 3'S, 4S, 4'S) -Dicyclohexyl-3,3'4,4'-tetracarboxylic acid (trans-
The chemical formula of DCTA-2) is shown below.

[0026]

Embedded image

According to the present invention, (1R, 1 '
R, 3R, 3'R, 4R, 4'R) -Dicyclohexyl-3,3'4,4'-tetracarboxylic acid (trans-
The chemical formula of DCTA-3) is shown below.

[0028]

Embedded image

[0029]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples.

Capillary chromatography (CG
C) is Hitachi GC263-70, column: DB-5 (J &
W Scientific) 5% Phenyl-95%
It was measured at a methylpolysiloxane thickness of 0.25 μm, a diameter of 0.25 mm, 60 m, and a column temperature of 275 ° C. High performance liquid chromatography is Shimadzu SCL
-10 A, column: Chiralcel OD (manufactured by Daicel Chemical Industries, Ltd.) 0.46 cmφ, 25 cm, 20 ° C.,
EtOH / n-hexane (10/90), 0.5 m
It was measured at L / min. ¹ H NMR spectrum (40
0 MHz) was measured at 25 ° C., JEOL JEOL 400X, DMSO solution.

Synthesis Example 1 100 g of BPT in a 500 mL rotating autoclave
M, 2.5 g of 5% Rh / C, and 200 mL of tetrahydrofuran were charged and heated at 100 ° C. under a constant pressure of 30 kg / cm ² of hydrogen at 300 rpm for 5.5 hours (the absorption of hydrogen was completed in about 5 hours) ). After the reaction solution was filtered using No. 5c filter paper, tetrahydrofuran was distilled off to obtain 101.8 g (yield 99%) of a viscous product.
This was dissolved in 400 mL of methanol and crystallized to obtain 72 g of cis-DCTM. According to HPLC analysis, cis-DCTM-x / cis-DCTM-y /
cis-DCTM-z = 51/28/21.

10 g of this cis-DCTM is added to 500 mL
And a homogenous solution was prepared with 50 mL of n-butanol. To this was added 65 g of a 10% aqueous NaOH solution, and the mixture was refluxed for 3 hours. Thereafter, n-butanol and desorbed methanol were distilled off, and water was removed while adding 200 mL of water to remove about 200 mL. The reaction solution was filtered, and 15 mL of concentrated hydrochloric acid was added to adjust the pH to 1, whereby a precipitate was deposited. The mixture was filtered, washed with water, and washed until no Cl ion was detected. Vacuum drying at 100 ° C. yielded 6.20 g of product (72% yield). This cis-DCTA was converted to a methyl ester using trimethylsilyldiazomethane and analyzed by HPLC. cis-DCTA-x /
cis-DCTA-y / cis-DCTA-z = 54 /
26/20.

Example 1 5 g of cis-DCTA obtained in Synthesis Example 1 was placed in a 300 mL locking autoclave, 25 mL of water was added, and the mixture was heated to 220 ° C. The water pressure became about 30 kg / cm ² , and the mixture was shaken for 6 hours. The precipitated crystals were collected by filtration, washed with 5 mL of water, and dried to obtain 1.78 g of a product. The filtrate and the washing solution were combined and again
C. and shaken for 6 hours. From this reaction, 1.1
7 g of the product were obtained. 2.95 g in total (59% yield).

If the filtrate is further treated in the same manner,
ns-DCTA can be obtained. trans-DC
TA was converted to the methyl ester using trimethylsilyldiazomethane and analyzed by CGC and HPLC. CG of cis-DCTA (methyl ester) used for starting
C is shown in FIG. 1a, and CGC of the reaction product (ester) is shown in FIG.
b. As a result, trans-DCTA-1 /
trans-DCTA-2 / trans-DCTA-3
Are present in a ratio of 50/25/25.

¹ HNM of cis-DCTA used for starting
The R spectrum (cyclohexane part) is shown in FIG. 2a.
Two equatorial hydrogens at the 4- and 4'-positions at 3.00 ppm and two axial hydrogens at the 3- and 3'-positions at 2.34 ppm were clearly suggested to be a cis structure. (The proton in the COOH part is 1
2.04 ppm). On the other hand, FIG. 2B shows the ¹ H NMR spectrum (cyclohexane part) of the reaction product. Four axial hydrogens at the 3,4- and 3 ', 4'-positions were observed at 2.36 and 2.29 ppm, which clearly suggested a trans structure (the proton in the COOH moiety was 12. 08 ppm).

Example 2 5 g of cis-DCTA obtained in the synthesis example was placed in a 300 mL rocking type autoclave, 30 mL of water was added, nitrogen was pressurized at 5 kg / cm ² , and the mixture was heated to 230 ° C. The pressure became approximately 37 kg / cm ² , and the mixture was shaken for 6 hours. The precipitated crystals were filtered, washed with 5 mL of water, and dried to obtain 2.58 g of a product. The filtrate and the washing solution were combined, heated again to 230 ° C., and shaken for 6 hours. The reaction yielded 1.21 g of product. A total of 3.79 g (76% yield). If the filtrate is further treated similarly, trans-DCTA can be obtained.

[0037]

The present invention provides trans-dicyclohexyl-3,3'4,4 'which is suitable as a polyimide precursor.
-Is a tetracarboxylic acid, (1R, 1'S, 3R,
3'S, 4R, 4'S) -Dicyclohexyl-3,3 '
4,4′-tetracarboxylic acid, (1S, 1 ′S, 3S,
3'S, 4S, 4'S) -Dicyclohexyl-3,3 '
4,4′-tetracarboxylic acid, and (1R, 1′R,
3R, 3'R, 4R, 4'R) -Dicyclohexyl-
A method for producing 3,3′4,4′-tetracarboxylic acid can be provided.

[Brief description of the drawings]

FIG. 1 shows the starting material c used in the examples.
is-DCTA and hydrolysis products (esterified products)
CGC.

FIG. 2 shows the starting material ci used in the examples.
s-DCTA and ¹ of cyclohexane part of reaction product
It is an HNMR spectrum.

Claims (1)

[Claims] 1. A product obtained by hydrogenating tetramethyl biphenyl-3,3'4,4'-tetracarboxylate is recrystallized to preferentially separate isomers having a cis structure. Cis-tetracarboxylic acid obtained by hydrolysis
(1R, 1'S, 3R, 3'S, 4R,
4 ′S) -dicyclohexyl-3,3′4,4′-tetracarboxylic acid, (1S, 1 ′S, 3S, 3 ′S, 4S,
4 ′S) -dicyclohexyl-3,3′4,4′-tetracarboxylic acid and / or (1R, 1′R, 3R,
3′R, 4R, 4′R) -Dicyclohexyl-3,3 ′
A method for producing trans-dicyclohexyl-3,3'4,4'-tetracarboxylic acid comprising 4,4'-tetracarboxylic acid.