Process for the optical resolution of 3-(p-chlorophenyl)-glutaramide
US6051734A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 19, 1998 |
| Grant date | Apr 18, 2000 |
| Priority date | — |
| Expiry date | Jun 19, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C211/27
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for the optical resolution of racemic 3-(p-chlorophenyl)glutaramide (GAM) into its R isomer R--COOH and its S isomer S--COOH, which process includes the steps of either: PA1 (1) reacting racemic 3-(p-chlorophenyl)-glutaramide dissolved in a suitable solvent with S-(-)-.alpha.-methylbenzylamine of the formula H.sub.2 N--S' PA1 (2) precipitating out of the solution of step (1) R--CO.sub.2.sup.-.H.sub.3.sup.+ N--S'; PA1 (3) dissolving the precipitate of step (2) in water, with the addition of a suitable acid; and PA1 (4) precipitating out of the solution of step (3) R--COOH; or PA1 (5) reacting racemic -3-(p-chlorophenyl)-glutaramide dissolved in a suitable solvent with R-(+)-.alpha.-methylbenzylamine of the formula H.sub.2 N--R'; PA1 (6) precipitating out of the solution of step (5) S--CO.sub.2.sup.-.H.sub.3.sup.+ N--R'; PA1 (7) dissolving the precipitate of step (6) in water, with the addition of a suitable acid, and PA1 (8) precipitating out of the solution of step (7) S--COOH. The R isomer of GAM may be used for the production of R-baclofen and the S isomer of GAM may be used for the production of S-baclofen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.