JPH09241227A - New optical resolution agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new optically active carboxylic acid derivative useful as an optical resolution, agent of a racemic amine derived from a trans-1,2- cyclohexane-1,2-dicarboxylic acid anhydride as a starting raw material. SOLUTION: This optical resolution agent is an optically active 2- aminocyclohexane carboxylic acid derivative of formula I (R is an alkyl, aralkyl or arylsulfonyl capable of having a substituted group or a cyclic aliphatic acyl capable of having a substituted group; * exhibits an unsaturated carbon atom), e.g. trans-2-acetamide cyclohexane carboxylic acid. The compound of the formula I is obtained by affecting a concentrated ammonium to a trans-1,2- cyclohexane dicarboxylic acid anhydride, reacting with sodium hydroxide to form a compound of formula II, reacting with sodium hypochlorite to form a compound of formula III, further reacting with an acid anhydride or an acid chloride to form a compound of formula IV, then neutralizing with hydrochloric acid to form a compound of formula V and at last subjecting to optical resolution.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an optically active 2-aminocyclohexanecarboxylic acid derivative and an optical resolution method for racemic amines using the derivative as an optical resolution agent.

[0002]

2. Description of the Related Art Optically active carboxylic acids are useful substances as optical resolving agents, but only 2-racemic form of 2-aminocyclohexanecarboxylic acid derivative is known.
So far, no examples of producing an optically active substance and an attempt to utilize it as an optical resolving agent have been found.

Optically active amines such as optically active α-amino-ε-caprolactam are compounds useful as an optical resolving agent or as a pharmaceutical intermediate. Racemic α easily synthesized industrially from synthetic raw materials such as nylon
For the optical resolution of -amino-ε-caprolactam,
Already (i) a method using a diastereomeric salt with tartaric acid (Japanese Patent Publication No. 59-44358), and (ii) a method using a diastereomeric salt with Np-nitrobenzoylglutamic acid (Japanese Patent Publication No. 48-3635). Gazette), (iii) a method using a diastereomeric salt with N-carbamoyl-valine (French Patent No. 1559885), (iv) a method using preferential crystallization of a magnesium salt (US Patent No. 40).
No. 62839), (v) Method using preferential crystallization of nickel salt (J. Org. Chem., 44 (26), 484).
1-7, (1979)), (vi) a method using a diastereomeric salt with N-benzoylmethionine (JP-B-62-62)
No. 114969), (vii) a method using a diastereomeric salt with N-benzoylalanine (Japanese Patent Publication No. 62-62-
114968), (viii) a method using a diastereomeric salt with N-acetylindoline-2-carboxylic acid (Japanese Patent Publication No. 61-24573), and the like. As another method using yeast, (ix) using L-α-amino-ε-caprolactam-assimilating yeast, D-α-
Method for producing amino-ε-caprolactam (Japanese Patent Publication No. Sho 5)
No. 8-155096) and the like are known.

However, these methods are not only difficult to separate and recover the respective components from the crystallized hardly soluble salt, but also have drawbacks such as low optical purity and low yield.

[0005]

The object of the present invention is to provide a novel optically active carboxylic acid derivative useful as an optical resolving agent for racemic amines, and to provide racemic α-amino-
An object of the present invention is to provide an optical resolution method for racemic amines such as ε-caprolactam.

[0006]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventor found that trans-1, 2
-Starting from cyclohexane-1,2-dicarboxylic acid anhydride as a starting material, it was found that a novel optically active 2-aminocyclohexanecarboxylic acid derivative obtained via a series of reaction steps described later is well suited to the above purpose, The present invention has been completed.

That is, the present invention has the general formula (I)

[0008]

Embedded image (In the formula, R is an alkyl, aralkyl or arylsulfonyl group having 1 to 10 carbon atoms which may have a substituent, or a straight chain, branched chain or cyclic group having 1 to 7 carbon atoms which may have a substituent. A novel optically active 2-aminocyclohexanecarboxylic acid derivative represented by an aliphatic acyl group, * represents an asymmetric carbon atom) and a racemic amine using the derivative as an optical resolving agent, particularly a racemic α-amino-ε- An optical resolution method of caprolactam.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Optical activity 2 represented by the above general formula (I)
-Trans-1,2-cyclohexanedicarboxylic acid anhydride, which is a starting material of an aminocyclohexanecarboxylic acid derivative, is, for example, cis- which is industrially easily available.
By heating and refluxing 1,2-cyclohexanedicarboxylic acid anhydride and sulfuric acid, trans-1,2-cyclohexanedicarboxylic acid is obtained, and by further heating and refluxing with acetyl chloride, it can be easily synthesized in a high yield. Yes [Journal of Organic Chemistry, 34 (1), 55, (197
6)].

The optically active 2-aminocyclohexanecarboxylic acid derivative (I) of the present invention can be produced from trans-1,2-cyclohexanedicarboxylic acid anhydride according to the following series of reaction routes.

[0011]

Embedded image R in the formula is, for example, methanesulfonyl, trifluoromethanesulfonyl, ethanesulfonyl, cyclohexanesulfonyl, toluenesulfonyl, benzenesulfonyl, nitrobenzenesulfonyl, chlorobenzenesulfonyl, naphthalenesulfonyl, or the like having 1 to 1 carbon atoms.
Alkyl, aralkyl or arylsulfonyl groups of 0, or linear, branched or cyclic aliphatic acyl groups having 1 to 7 carbon atoms such as acetyl, trifluoroacetyl, chloroacetyl, propionyl, pivaloyl or cyclohexanecarbonyl.

That is, the trans-1,2-cyclohexanedicarboxylic acid anhydride (A) is reacted with concentrated ammonia water under ice cooling to cause a ring-opening reaction, and then with a sodium hydroxide aqueous solution to act trans-2-. It is designated as carbamoylcyclohexanecarboxylic acid sodium salt (B). Without isolating this, the reaction solution was subsequently concentrated under reduced pressure, and sodium hypochlorite aqueous solution was added in the presence of sodium hydroxide aqueous solution to carry out heating reaction.
2-Aminocyclohexanecarboxylate sodium (C) is produced, and an acid anhydride or acid chloride represented by the general formula R ₂ O or RCl is allowed to act on it to give a corresponding t
The trans-2-substituted aminocyclohexacarboxylic acid sodium salt (D) is prepared, and then neutralized with hydrochloric acid to obtain the trans-2-substituted aminocyclohexanecarboxylic acid (E).

The optical resolution of the trans-2-substituted aminocyclohexanecarboxylic acid (E) in the final step is carried out by using a suitable optically active amine such as optically active α-methylbenzylamine, optically active solvent in ethanol, water or a mixed solvent thereof. α-Amino-ε-caprolactam and the like are allowed to act to obtain crystals of a diastereomeric salt, which are subsequently dissolved in an alkaline aqueous solution such as an aqueous solution of sodium hydroxide and the like, and the amine is removed by solvent extraction, followed by medium extraction with hydrochloric acid or the like. It is carried out by crystallization. As shown in Examples below, for example, an optically active α-amino-ε-caprolactam is used as an optical resolving agent for trans-2-acetamidocyclohexanecarboxylic acid, and an optical resolving agent for trans-2-benzenesulfonamidocyclohexanecarboxylic acid. Can be efficiently achieved by using an optically active α-methylbenzylamine as.

The optically active 2-aminocyclohexanecarboxylic acid derivative of the present invention includes racemic amines such as racemic α-amino-ε-caprolactam, racemic amino acid esters such as racemic t-leucine methyl ester and racemic β. -Cyclohexylalanine methyl ester, racemic leucine methyl ester, racemic proline methyl ester, racemic pipecolic acid methyl ester and the like are preferably used as optical resolving agents.

Racemic α-amino-ε-using the optically active 2-aminocyclohexanecarboxylic acid derivative of the present invention
Optical resolution of caprolactam is performed under the following procedure and conditions.

First, in a solvent, racemic α-amino-ε
-0.1 to 20 mol, preferably 0.5 to 1.0 mol, of an optically active 2-aminocyclohexanecarboxylic acid derivative is brought into contact with 1 mol of caprolactam, and the solution is cooled or concentrated. Then, a sparingly soluble diastereomeric salt crystallizes out. The temperature at which the sparingly soluble salt is precipitated from the splitting solvent may be in the range from the freezing point to the boiling point of the solvent used, and may be appropriately determined depending on the purpose, but is usually 0 to 80 ° C.
Is sufficient.

The solvent used in the present invention is not particularly limited as long as it does not adversely affect the reaction, the raw materials are dissolved to the extent necessary for the reaction, and the diastereomeric salt can be obtained. , Water, methanol, ethanol,
Examples include lower alcohols such as propanol, acetone, acetic acid, ethyl acetate, tetrahydrofuran, and mixed solvents thereof. The amount of these solvents used is not particularly limited as long as the reaction liquid can be efficiently stirred, but is usually 1 to 100 times by volume, preferably the volume of the racemic α-amino-ε-caprolactam as a raw material, Is 5-5
It is 0 times the capacity.

In the present invention, racemic α-amino-ε
-The method of bringing the optically active 2-aminocyclohexanecarboxylic acid derivative into contact with caprolactam is as follows: individually dissolving the racemic α-amino-ε-caprolactam and the optically active 2-aminocyclohexanecarboxylic acid derivative in the above solvent, respectively. They may be mixed, or they may be sequentially dissolved in a solvent. Alternatively, a salt prepared in advance from racemic α-amino-ε-caprolactam and an optically active 2-aminocyclohexanecarboxylic acid derivative may be added and dissolved in a solvent.

Crystals of a poorly soluble diastereomer salt can be easily separated by a usual solid-liquid separation method such as filtration or centrifugation.

On the other hand, it is also possible to separate the mother liquor from which the sparingly soluble diastereomeric salt has been separated, as it is, or to concentrate or cool it to precipitate a sparingly soluble diastereomeric salt and separate it.

The method for decomposing each diastereomeric salt thus obtained is arbitrary, and for example, treatment with an acid / alkali is performed to separate and collect each component.

The method of the present invention is the method of L-α-amino-
It is also applicable when a racemic mixture containing an excess of either ε-caprolactam or D-α-amino-ε-caprolactam is used as a raw material.

[0023]

The present invention will be described in more detail with reference to the following examples. Of course, the present invention is not limited to these.

Example 1 Synthesis of trans-2-acetamidocyclohexanecarboxylic acid 40 ml of concentrated ammonia water and 50 ml of water were added to a 300 ml eggplant-shaped flask with a slot and ice-cooled. To this, 30.803 g (0.2 mol) of trans-1,2-cyclohexanedicarboxylic acid anhydride crushed using a mortar was added little by little to completely dissolve the anhydride, and then 1
Stir slowly for 0 minutes. Sodium hydroxide 26.91
7 g (content: 93%, 0.6 mol) was dissolved in 80 ml of water and half of an ice-cooled aqueous solution was added dropwise little by little. After the dropping, the reaction solution was evaporated while keeping the bath temperature at 50 ° C. or lower, and distilled under reduced pressure until about 20 ml of water flowed out. The above reaction solution was transferred to a 500 ml three-necked flask, and half of the remaining sodium hydroxide aqueous solution was added while cooling. 120 ml of 1.5M sodium hypochlorite is stirred to about 1 with stirring.
The mixture was added dropwise over 5 minutes, and after stirring for 5 minutes, the bath temperature was changed to 86 ° C, and the temperature of the reaction solution was kept at 80 to 85 ° C for 5 minutes.
The ice bath was replaced again and the reaction solution was cooled to 10 ° C or lower. With vigorous stirring, 24.269 g of acetic anhydride (0.238 g
(mol) was added dropwise over 2 hours. After completion of dropping, the mixture was stirred for 30 minutes. About 95 ml of 6M hydrochloric acid was added to acidify Congo red, and the precipitated crystals were filtered by suction and dried with a desiccator to obtain crude crystals of trans-2-acetamidocyclohexanecarboxylic acid. Yield 23.210 g Yield 62.7% mp.198-
213 ° C

This is further added with ethyl acetate and ethanol
Recrystallized with 95 ml of (1: 2) mixed solvent and purified tran
Crystals of s-2-acetamidocyclohexanecarboxylic acid were obtained. Yield 15.366 g Yield 41.5% mp 210
211 ° C

The mother liquor was concentrated to a quarter with an evaporator, and the precipitated crystals were filtered and washed with ethyl acetate and ethanol.
After recrystallization using a mixed solvent of (1: 2), water 6
Recrystallization from 0 ml gave purified trans-2-acetamidocyclohexanecarboxylic acid crystals. Yield 3.920 g Yield 10.6% mp 210-2
11 ° C

Example 2 Optical resolution of trans-2-acetamidocyclohexanecarboxylic acid In a 50 ml Erlenmeyer flask, (±) -trans-2-acetamidocyclohexanecarboxylic acid 2.778 g (15 m)
mol), ethanol and water mixed solvent (4: 1) 33m
After 1 was added, 1.923 g (15 mmol) of L-(−)-α-amino-ε-caprolactam was added and heated until completely dissolved. After cooling to 50 ° C., a small amount of seed crystals of a poorly soluble salt was added, and the mixture was left at room temperature for 30 hours. The precipitated crystals were separated by filtration, dried with a desiccator, and the sparingly soluble salt (-)-
A trans-2-acetamidocyclohexanecarboxylic acid.L-(-)-α-amino-ε-caprolactam salt was obtained. Yield 1.949 g Yield of half racemic compound as 100% 82.9% mp 209 to 212 ° C

This salt was mixed with a mixed solvent of ethanol and water (8:
1) Recrystallized with 7.8 ml and purified (-)-trans-2
-Acetamide cyclohexanecarboxylic acid L-(-)
A -α-amino-ε-caprolactam salt was obtained. Yield 1.493 g Yield with half of racemate as 100% 77.0% mp 214-216 ° C [α] 589
-12.0 ° (c1, MeOH)

A part of this salt was metathesized to obtain (-)
-Trans-2-acetamidocyclohexanecarboxylic acid was derivatized to the benzyl ester, followed by CHIRALC.
When the optical purity was assayed by high performance liquid chromatography using ELOJ, the optical purity was 99.9%.

To 1.535 g of this salt, 3.5 ml of water and 3M
1.7 ml of sodium hydroxide was added, and chloroform 2.5 was added.
The mixture was extracted 3 times with ml, the aqueous layer was acidified with about 2.5 ml of 4 M hydrochloric acid, and suction-filtered to give an optically active (-)-tr.
0.355 g of ans-2-acetamidocyclohexanecarboxylic acid was obtained. mp 170 to 171 ° C [α] 589-18.2 °
(C1, MeOH)

The filtrate was extracted three times with 2.5 ml of ethyl acetate, and 0.266 g of (-)-trans-2-acetamidocyclohexanecarboxylic acid was recovered from the organic layer. mp.175-176 ° C

Reference Example 1 Trans-2-acetamidocyclohexanecarboxylic acid optical purity assay method In a two-necked flask equipped with a 30 ml pickpocket, (±) -trans was used.
-2-acetamidocyclohexanecarboxylic acid 93 mg
(0.5 mmol) was added and suspended in 2 ml of dry methylene chloride, and then benzyl alcohol (1 mmol),
4-dimethylaminopyridine (1 mmol), and N,
N'-dicyclohexylcarbodiimide (1 mmol)
Were sequentially added, and the mixture was stirred at room temperature overnight. Next, 1m ethyl acetate
l was added and filtered, 2 ml of saturated saline was added to the filtrate, the mixture was stirred for 1 hour, the organic layer was dried over anhydrous sodium sulfate, the solvent was distilled off with an evaporator, and TLC (developing solvent: ethyl acetate / hexane, Rf = 0.3) to obtain trans-2-acetamidocyclohexanecarboxylic acid benzyl ester. The optical purity was calculated under the following conditions.

Measurement conditions: column: CHIRALCEL OJ transfer phase: 7% 2-propanol / hexane flow rate: 0.5 ml / min detection wavelength: 254 nm retention time: 31 min; (+)-trans-2-acetamidocyclohexane Carboxylic acid benzyl ester,
35 min; (-)-trans-2-acetamidocyclohexanecarboxylic acid benzyl ester

Example 3 Synthesis of trans-2-benzenesulfonamide cyclohexanecarboxylic acid To a 300 ml eggplant-shaped flask equipped with a slot, 30 ml of concentrated ammonia water and 40 ml of water were added, and the mixture was cooled with ice. 23.155 g (0.15 m) of trans-1,2-cyclohexanedicarboxylic acid anhydride crushed using a mortar
ol) was added little by little to completely dissolve the anhydride,
Stir slowly for another 10 minutes. Sodium hydroxide 1
9.202 g (content 93%, 0.45 mol) was added to water 10
Half the amount of an aqueous solution dissolved in 0 ml and cooled with ice was added dropwise little by little. After the dropping, the reaction solution was subjected to an evaporator while keeping the bath temperature at 50 ° C or lower, and distilled under reduced pressure until about 20 ml of water was distilled off. The above reaction solution was transferred to a 500 ml three-necked flask, and half of the remaining sodium hydroxide aqueous solution was added while cooling. 1.5M sodium hypochlorite under stirring 9
0 ml was added dropwise in about 10 minutes, and after stirring for 5 minutes, the bath temperature was changed to 86 ° C, and the temperature of the reaction solution was adjusted to 80 to 85 ° C at 5 ° C.
Hold for a minute. The ice bath was replaced again and the reaction solution was cooled to 10 ° C or lower. With vigorous stirring, 26.500 g (0.15 mol) of benzenesulfonyl chloride and dioxane 2
2.5 ml of the mixed solution was added dropwise over 3 hours. After completion of dropping, the mixture was stirred for 10 minutes. About 25 ml of concentrated hydrochloric acid was added to acidify Congo red, and the precipitated crystals were suction filtered and
The mixture was transferred to a 00 ml beaker, 250 ml of boiling water was added thereto, and after sufficiently stirring, suction filtration was performed while hot. The obtained crude product was recrystallized with 48 ml of 80% ethanol. Yield 22.183g Yield 52.1% mp.185-
190 ° C

This was recrystallized with 35 ml of 80% ethanol to obtain crystals of purified trans-2-benzenesulfonamide cyclohexanecarboxylic acid. Yield 20.853 g 49.0% mp 190-
191 ° C

Example 4 Optical resolution of trans-2-benzenesulfonamide cyclohexanecarboxylic acid (±) -trans-2-benzenesulfonamide cyclohexanecarboxylic acid 2.83 in a 200 ml Erlenmeyer flask.
5 g (10 mmol) and ethanol: ethyl acetate (1: 1)
75 ml of the mixed solvent of (1) and 11.21 g (10 mmol) of (−)-α-methylbenzylamine were added, and the mixture was heated until completely dissolved. The mixture was allowed to stand at room temperature for 8 hours, the precipitated crystals were filtered off and dried, and the sparingly soluble salt (+)-trans-2-
Benzenesulfonamide cyclohexanecarboxylic acid
(−)-Α-Methylbenzylamine salt was obtained. Yield 1.251 g Yield 61.8% with half amount of racemate as 100% mp 174-178 ° C [α] 589
+ 12.4 ° (c1, MeOH)

This salt was added to ethanol and ethyl acetate (1:
Recrystallized twice with 40 ml of the mixed solvent of 1) and purified (+)-
A trans-2-benzenesulfonamide cyclohexanecarboxylic acid · (−)-α-methylbenzylamine salt was obtained. Yield 0.749 g Yield 37.0% with half of the racemate as 100% mp 185 to 187 ° C. [α] 589
+ 20.1 ° (c1, MeOH)

0.149 g (0.37 mmo) of the salt obtained
1 ml of water and 0.6 ml of 1 M sodium hydroxide were added to l), and the liberated (-)-α-methylbenzylamine was extracted with ether, and then the aqueous layer was acidified with Congo red by adding 1 M hydrochloric acid. The precipitated crystals are filtered, and (+)-tr
77 mg of ans-2-benzenesulfonamide cyclohexanecarboxylic acid was obtained. After converting this to isobutyl ester, the optical purity was assayed by high performance liquid chromatography analysis using CHIRALCEL OD-H, and it was 99.9% or more.

Reference Example 2 Assay for Optical Purity of trans-2-Benzenesulfonamidocyclohexanecarboxylic Acid trans-2-Benzenesulfonamidocyclohexanecarboxylic acid was heated to reflux with isobutyl alcohol in the presence of phosphorus oxychloride to give trans-2-. It was derivatized to the ester form of benzenesulfonamide cyclohexanecarboxylic acid. After the reaction, water was added to decompose excess phosphorus oxychloride, the remaining isobutyl alcohol and hydrochloric acid were removed by an evaporator, and the mixture was extracted with ethyl acetate. TLC (developing solvent: ethyl acetate / hexane = 1: 1, Rf = 0.6)
Was purified to give trans-2-benzenesulfonamide cyclohexanecarboxylic acid isobutyl ester. The optical purity was calculated under the following conditions.

Measurement conditions: column: CHIRALCEL OD-H transfer phase: 4% 2-propanol / hexane flow rate: 0.5 ml / min detection wavelength: 254 nm retention time: 33 min; (-)-trans-2- Benzenesulfonamide cyclohexanecarboxylic acid isobutyl ester, 38 min; (+)-trans-2-benzenesulfonamide cyclohexanecarboxylic acid isobutyl ester

Example 5 Optical resolution of (±) -α-amino-ε-caprolactam with optically active trans-2-acetamidocyclohexanecarboxylic acid (±) -α-amino-ε-caprolactam 0.128 g
(1 mmol) and (−)-trans-2-acetamidocyclohexanecarboxylic acid 0.185 g (1 mmol)
Were mixed, 3 ml of ethanol and 0.5 ml of water were added, and the mixture was heated and dissolved. When the temperature reached about 50 ° C., a small amount of seed crystals of a sparingly soluble salt were added and the mixture was allowed to stand at room temperature for 13 hours. The precipitated crystals were filtered by suction to obtain a sparingly soluble salt (−)-α-amino-ε-caprolactam. (−)-Trans-2-acetamidocyclohexanecarboxylic acid salt. Yield 0.121g Yield with half of racemate as 100% 77.2% mp 214-216 ° C

(-) Obtained by metathesis of a portion of this salt
After benzoylating -α-amino-ε-caprolactam, HPLC analysis using CHIRALCEL OD-H revealed that the optical purity was 99.9%.

Example 6 (±) -α-amino-ε-with optically active trans-2-benzenesulfonamide cyclohexanecarboxylic acid
Optical resolution of caprolactam (±) -α-amino-ε-caprolactam 0.256 g
(2 mmol) and (-)-trans-2-benzenesulfonamide cyclohexanecarboxylic acid 0.567 g (2
(mmol) and mixed with 10 ml of 2-propanol, and heated and dissolved. When the temperature reached about 50 ° C., a small amount of a seed crystal of a poorly soluble salt was added and the mixture was allowed to stand at room temperature for 6.5 hours. The precipitated crystals were suction filtered to give a sparingly soluble salt (-)-α-amino-
ε-caprolactam · (−)-trans-2-benzenesulfonamide cyclohexanecarboxylic acid salt was obtained. Yield 0.275 g Yield 67.0% with half of racemate as 100% mp 161 to 163 ° C

(−) Obtained by metathesis of a part of this salt
As a result of HPLC analysis using -α-amino-ε-caprolactam, the optical purity was 73.8%.

Reference Example 3 Optical purity assay method for α-amino-ε-caprolactam (±) -α-amino-ε-caprolactam 0.384 g
(3 mmol) was added with 4 ml of dry methylene chloride and cooled in an ice bath, and 0.617 g (6 m of triethylamine was added thereto.
mol), benzoyl chloride 0.843 g (6 mmol)
Was added and stirred at room temperature for 3 hours. After completion of the reaction, the solvent was removed by an evaporator and purification by TLC was performed to obtain α-benzamide-ε-caprolactam. The optical purity was calculated under the following conditions.

Measurement conditions: column: CHIRALCEL OD-H transfer phase: 10% 2-propanol / hexane flow rate: 0.5 ml / min detection wavelength: 254 nm retention time: 35 min; (-)-α-benzamide- ε
-Caprolactam, 43 min; (+)-α-benzamide-ε-caprolactam

[0047]

INDUSTRIAL APPLICABILITY According to the present invention, by using an optically active 2-aminocyclohexanecarboxylic acid derivative as an optical resolving agent, an optically active α-useful as an intermediate for pharmaceuticals and the like is obtained.
An easy and efficient production of amino-ε-caprolactam has become possible.

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Claims (6)

[Claims] 1. A compound represented by the general formula (I): (In the formula, R is an alkyl, aralkyl or arylsulfonyl group having 1 to 10 carbon atoms which may have a substituent, or a straight chain, branched chain or cyclic group having 1 to 7 carbon atoms which may have a substituent. An optically active 2-aminocyclohexanecarboxylic acid derivative represented by an aliphatic acyl group and * represents an asymmetric carbon atom. 2. The compound according to claim 1, wherein R is an acetyl group. 3. The compound according to claim 1, wherein R is a benzenesulfonyl group. 4. The compound according to claim 1, wherein the optically active 2-aminocyclohexanecarboxylic acid derivative is a trans isomer. 5. A compound represented by the general formula (I): (In the formula, R is an alkyl, aralkyl or arylsulfonyl group having 1 to 10 carbon atoms which may have a substituent, or a straight chain, branched chain or cyclic group having 1 to 7 carbon atoms which may have a substituent. An optically active 2-aminocyclohexanecarboxylic acid derivative represented by an aliphatic acyl group (* represents an asymmetric carbon atom) is allowed to act on a racemic amine as an optical resolving agent, and the difference in solubility of the produced diastereomeric salt is utilized. Optical resolution of a racemic amine, which is characterized by performing optical resolution. 6. The optical resolution method according to claim 5, wherein the racemic amine is α-amino-ε-caprolactam.