Racemization of an enantomerically enriched .alpha.-aryl carboxylic acid

US5332834A · kind A · utility

Assignee

• Hoechst Celanese Corporation · US

Inventors

• Apurba Bhattacharya · Port Aransas, US
• John R. Fritch · Port Aransas, US
• Carl D. Murphy · Port Aransas, US
• Larry D. Zeagler · Port Aransas, US
• Carina Araullo-McAdams · Wilmington, US

Key dates

• Filing date: Dec 2, 1992
• Grant date: Jul 26, 1994
• Expiry date: Dec 2, 2012

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/43
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

There is disclosed and claimed a process whereby S(+)-ibuprofen L-lysinate salt is produced by selective precipitation from a mixture containing enantiomers of ibuprofen and L-lysine. The quantity of L-lysine is not more than about a molar equivalent of the quantity of S(+)-ibuprofen in the ibuprofen enantiomeric mixture. The mother liquors after separating the above salt are enriched in R-ibuprofen which is racemized by a novel thermal racemization process and may then be recycled.