Method for producing optically active compound

Patent metadata

Field	Value
Publication number	US-2023257408-A1
Application number	US-202118005161-A
Country	US
Kind code	A1
Filing date	Jul 6, 2021
Priority date	Jul 17, 2020
Publication date	Aug 17, 2023
Grant date	—

Abstract

An object of the present invention is to provide a further more effective process for preparing a certain optically active compound including an optically active 1-acetyl-2,2,4-trimethyl-1,2,3,4-tetrahydroquinoline.The present invention provides a process for an optically active compound represented by formula (3) (wherein R5 represents a hydrogen atom etc., R6 and R7 each independently represents a hydrogen atom, etc., R8 represents a C1-C6 alkyl group, and R9, R10 and R11 each independently represents a hydrogen atom, etc. The carbon atom with a symbol of the asterisked “*” represents an asymmetric carbon atom),which comprises a reacting a compound represented by formula (2) (wherein R5, R6, R7, R8, R9, R10, and R11 has the same meanings as the above) with hydrogen in the presence of asymmetric cobalt complex.

First claim

1 . A process for preparing an optically active compound represented by formula (3):

(wherein
R 5 represents a hydrogen atom, or a C1-C6 alkyl group which may optionally have one or more substituents,
R 6 and R 7 each independently represents a hydrogen atom, or a C1-C6 alkyl group;
R 8 represents a C1-C6 alkyl group; and
R 9 , R 10 and R 11 each independently represents a hydrogen atom, a halogen atom, an amino group, a hydroxy group, a C1-C6 alkyl group which may optionally have one or more substituents, a C1-C6 alkoxy group which may optionally have one or more substituents, a C2-C7 alkylcarbonyl group which may optionally have one or more substituents, or a C6-C10 aryl group which may optionally have one or more substituents; and
the carbon atom with a symbol of the asterisked “*” represents an asymmetric carbon atom),

which comprises reacting a compound represented by formula (2):

(wherein each of R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , and R 11 has the same meanings as described above)
with hydrogen in the presence of an asymmetric cobalt complex.

2 . The process according to claim 1 wherein the asymmetric cobalt complex described in claim 1 represents a monovalent cobalt complex which is obtained by reacting an asymmetric cobalt complex represented by formula (1):

(wherein,
R 1 each independently represents a C1-C10 alkyl group which may optionally have one or more substituents, a C3-C10 cycloalkyl group which may optionally have one or more substituents, or a C6-C10 aryl group which may optionally have one or more substituents;
R 2 and R 3 each independently represents a hydrogen atom, a C1-C10 alkyl group which may optionally have one or more substituents, or a C6-C10 aryl group which may optionally have one or more substituents, or alternatively R 2 and R 3 are combined with each other together with a carbon atom to which they are attached to form a cycle;
R 4 represents a C1-C10 alkyl group which may optionally have one or more substituents, a C1-C10 alkoxy group which may optionally have one or more substituents, a C1-C10 alkylthio group which may optionally have one or more substituents, a C2-C11 alkoxycarbonyl group which may optionally have one or more substituents, a C2-C11 alkylcarbonyl group which may optionally have one or more substituents, a C6-C10 aryl group which may optionally have one or more substituents, a halogen atom, an amino group which may be optionally mono- or di-alkylated with C1-C10 alkyl group, a nitro group, a hydroxy group, a sulfo group, a C1-C10 alkylsulfonyl group, a C6-C10 arylsulfonyl group, or a halosulfonyl group;
n is 0, 1, 2 or 3;
when n is 0 or 1, a plurality of R 4 may be identical to or different from each other;
X represents a chlorine atom, a bromine atom or an iodine atom; and
the carbon atom with a symbol of the asterisked “*” represents an asymmetric carbon atom)

with a reducing agent.

3 . The process according to claim 2 wherein the reducing agent represents a hydride reducing agent, and the monovalent cobalt complex represents a hydride complex.

4 . The process according to claim 3 wherein the hydride reducing agent represents a trialkyl borohydride alkali metal salt.

5 . A process according to claim 3 wherein the reaction is carried out further in the presence of a divalent halogenated cobalt salt.

6 . The process according to claim 5 wherein an amount used of the divalent halogenated cobalt salt per 1 mole of the hydride complex is within a range of 2 moles or less.

7 . The process according to claim 3 wherein the reaction is carried out further in the presence of trialkylamine.

8 . The process according to claim 7 wherein an amount used of the trialkylamine per 1 mole of the compound represented by formula (2) is within a range of 0.5 moles to 3 moles.

9 . The process according to claim 2 wherein the reducing agent represents an alkyl lithium, and the monovalent cobalt complex represents an alkyl complex.

10 . A process for preparing an optically active compound, which comprises a step of reacting the optically active compound represented by formula (3) which is obtained in the process according to claim 1 with an acid to obtain an optically active compound represented by formula (4):

(wherein
each of R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , and R 11 has the same meanings as described above; and
the carbon atom with a symbol of the asterisked “*” represents an asymmetric carbon atom); and
further a step of reacting the obtained optically active compound represented by formula (4) with water to obtain a compound represented by formula (5):

(wherein
each of R 6 , R 7 , R 8 , R 9 , R 10 , and R 11 has the same meanings as described above; and
the carbon atom with a symbol of the asterisked “*” represents an asymmetric carbon atom).

11 . The process according to claim 10 wherein R 6 , R 7 and R 8 in the formula (5) represents a methyl group; and R 9 , R 10 and R 11 represents a hydrogen atom.

12 . A process for preparing an optically active 1,1,3-trimethyl-4-aminoindane, which comprises a step that after the optically active compound represented by formula (5) obtained in claim 11 is dissolved in a solvent, an optical resolution is carried out using the optically active tartaric acid.

13 . A process for preparing an optically active 1,1,3-trimethyl-4-aminoindane, which comprises a step that after the optically active compound represented by formula (5) obtained in claim 11 is dissolved in a solvent, a preferential crystallization is carried out by adding an acid.

14 . The process according to claim 13 wherein an acid dissociation constant (pKa) of the acid is less than 2.8.

15 . The process according to claim 12 wherein an enantiomeric ratio of the optically active compound represented by formula (5) is 70/30 or more as R-isomer/S-isomer.

16 . A process for preparing an optically active compound, which comprises further a step of reacting the optically active 1,1,3-trimethyl-4-aminoindane which is obtained by the process according to claim 12 with a compound represented by formula (6):

(wherein
R 12 and R 13 each independently represents a C1-C6 alkyl group which may be optionally substituted with one or more halogen atoms, or a hydrogen atom; and R 14 represents a halogen atom, a hydroxy group, or a C1-C6 alkoxy group which may be optionally substituted with one or more halogen atoms)

to obtain a compound represented by formula (7):

(wherein each of R 12 , R 13 and a symbol of the asterisked “*” has the same meanings as described above).

17 . An asymmetric cobalt complex represented by formula (1′):

(wherein
R 1 represents an isop

Assignees

• Sumitomo Chemical Co

Inventors

• Lutete Leopold Mpaka
• Hagiya Koji

Classifications

• C07C209/88

  Separation of optical isomers · CPC title

• C07F15/065 Primary

  without a metal-carbon linkage · CPC title

• C07C2602/08

  the other ring being five-membered, e.g. indane · CPC title

• C07B2200/07

  Optical isomers · CPC title

• B01J31/22 Primary

  Organic complexes · CPC title