Preparation of (S)-Clopidogrel and related compounds
US6858734B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 23, 2003 |
| Grant date | Feb 22, 2005 |
| Priority date | — |
| Expiry date | Apr 30, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/582
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for producing enantiomerically enriched (S)-α-(2-chlorophenyl)-6,7-dihydrothieno[3,2-c]pyridine-5 (4H)-acetic acid hydrocarbyl ester, represented by the formula: Is provided, wherein R1 and R2 are hydrogens and R3 is methyl (i.e., (S)-Clopidogrel). The process includes the steps of: (a) contacting N-2-chlorobenz-aldehyde-ylidene-1-ethylamine-2(2-thiophenyl)imine and an HCN source, in the presence of a non-metallic asymmetric Strecker catalyst to form enantiomerically enriched (S)-α,α-(2-thiophenylethylamino)(2-chlorophenyl)acetonitrile; (b) contacting the enantiomerically enriched (S)-α,α-(2-thiophenylethylamino)(2-chlorophenyl)acetonitrile and a formaldehyde equivalent, in the presence of an acid catalyst to form enantiomerically enriched α-5(4,5,6,7-tetrahydro[3,2-c]thienopyridyl)(2-chlorobenzyl)-nitrile; and (c) contacting the enantiomerically enriched α-5(4,5,6,7-tetrahydro[3,2-c]thienopyridyl)(2-chlorobenzyl)-nitrile and a reagent capable of converting a cyano group into an ester group to form enantiomerically enriched hydrocarbyl ester of (S)-α-(2-chlorophenyl)-6,7-dihydrothieno-[3,2-c]pyridine-5(4H)-acetic acid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.