Method for producing racemate of compound

Patent metadata

Field	Value
Publication number	US-9284260-B2
Application number	US-201314439597-A
Country	US
Kind code	B2
Filing date	Oct 28, 2013
Priority date	Nov 2, 2012
Publication date	Mar 15, 2016
Grant date	Mar 15, 2016

Abstract

A method for producing a racemate of a compound represented by Formula (1), including bringing a transition metal catalyst into contact with an optically active form of the compound represented by Formula (1):

[in Formula (1),
a ring X 1 represents an aromatic ring;
R 1 represents a C 1-6 alkyl group, a C 3-8 cycloalkyl group, or a C 1-6 halo-alkyl group;
R 2 is a group different from R 1 and represents a C 1-6 alkyl group, a C 3-8 cycloalkyl group, or a C 1-6 halo-alkyl group, or R 2 and the ring X 1 are bonded to each other to form a ring;
a hydrogen atom(s) of the ring X 1 is optionally replaced with a C 1-6 alkyl group, a C 1-6 halo-alkyl group, a cyano group, a nitro group, a C 1-6 alkoxy group, or a halogen atom; and
* represents an asymmetric carbon atom].

First claim

The invention claimed is:

1. A method for producing a racemate of a compound represented by Formula (1), comprising bringing a transition metal catalyst into contact with an optically active form of the compound represented by Formula (1):

[in Formula (1),
a ring X 1 represents an aromatic ring;
R 1 represents a C 1-6 alkyl group, a C 3-8 cycloalkyl group, or a C 1-6 halo-alkyl group;
R 2 is a group different from R 1 and represents a C 1-6 alkyl group, a C 3-8 cycloalkyl group, or a C 1-6 halo-alkyl group, or R 2 and the ring X 1 are bonded to each other to form a ring;
a hydrogen atom(s) of the ring X 1 is optionally replaced with a C 1-6 alkyl group, a C 1-6 halo-alkyl group, a cyano group, a nitro group, a C 1-6 alkoxy group, or a halogen atom; and
* represents an asymmetric carbon atom].

2. The production method according to claim 1 , wherein the compound represented by Formula (1) is a compound represented by Formula (1a):

[in Formula (1 a),
A 1 , A 2 , A A 3 , and A 4 each independently represent —N═ or —C(R a )═, and R a represents a hydrogen atom, a C 1-6 alkyl group, a C 1-6 halo-alkyl group, a cyano group, a nitro group, a C 1-6 alkoxy group, or a halogen atom;
R 3 represents a C 1-6 alkyl group, a C 3-8 cycloalkyl group, or a C 1-6 halo-alkyl group;
R 4 is a group different from R 3 and represents a C 1-6 alkyl group, a C 3-8 cycloalkyl group, or a C 1-6 halo-alkyl group, or when A 1 represents —C(R a )═, R 4 and R a are optionally bonded to each other form a divalent hydrocarbon group, and hydrogen atoms of the hydrocarbon group are optionally replaced with a halogen atom, and —CH 2 — of the hydrocarbon group is optionally replaced with —O—;
two R a 's of the adjacent —C(R a )═'s are optionally bonded to each other to form a benzene ring together with a carbon atom to which each of them is bonded, and a hydrogen atom(s) of the benzene ring are optionally replaced with a C 1-6 alkyl group or a halogen atom; and
* represents an asymmetric carbon atom].

3. The production method according to claim 2 , wherein A 1 , A 2 , A 3 , and A 4 are
C(R a )═.

4. The production method according to claim 2 , wherein A 1 is
—C(R a )═, and R a and R 4 are bonded to each other to form a divalent hydrocarbon group.

5. The production method according to claim 2 , wherein the compound represented by Formula (1a) is a compound represented by Formula (2):

[in Formula (2),
A 2 , A 3 , and A 4 each independently represent —N═ or —C(R a )═, R a represents a hydrogen atom, a C 1-6 alkyl group, a C 1-6 halo-alkyl group, or a halogen atom, and R 3 represents a C 1-6 alkyl group;
R d represents a C 1-6 alkyl group, or a C 1-6 halo-alkyl group, r represents an integer of 0 to 4, and when r is an integer of 2 or more, a plurality of R d 's are optionally the same or different; and
* represents an asymmetric carbon atom].

6. The production method according to claim 2 , wherein R 3 is a C 1-6 alkyl group.

7. The production method according to claim 1 , wherein the compound represented by Formula (1) is 1,1,3-trimethyl-4-aminoindane represented by Formula (3):

8. The production method according to claim 1 , wherein the transition metal catalyst is a hydrogen-absorbing transition metal catalyst having absorbed hydrogen therein.

9. The production method according to claim 1 , wherein the transition metal catalyst is a palladium catalyst.

10. The production method according to claim 9 , wherein the palladium catalyst is
a palladium-carbon catalyst.

11. A method for racemizing a compound represented by Formula (1), comprising
bringing a transition metal catalyst into contact with an optically active form of the compound represented by Formula (1):

[in Formula (1),
a ring X 1 represents an aromatic ring;
R 1 represents a C 1-6 alkyl group, a C 3-8 cycloalkyl group, or a C 1-6 halo-alkyl group;
R 2 is a group different from R 1 and represents a C 1-6 alkyl group, a C 3-8 cycloalkyl group, or a C 1-6 halo-alkyl group, or R 2 and the ring X 1 are bonded to each other to form a ring;
a hydrogen atom(s) of the ring X 1 is optionally replaced with a C 1-6 alkyl group, a C 1-6 halo-alkyl group, a cyano group, a nitro group, a C 1-6 alkoxy group, or a halogen atom; and
* represents an asymmetric carbon atom].

Assignees

• Sumitomo Chemical Co

Inventors

• Takahashi Tomoaki
• Hirose Taro

Classifications

• C07C211/60

  containing a ring other than a six-membered aromatic ring forming part of at least one of the condensed ring systems · CPC title

• C07C209/82

  Purification; Separation; Stabilisation; Use of additives · CPC title

• C07C2102/08

  Chemistry & Metallurgy · mapped topic

• C07B2200/07

  Optical isomers · CPC title

• C07B55/00 Primary

  Racemisation; Complete or partial inversion · CPC title