Process for the racemization of N-acetyl-D,L-.alpha.-aminocarboxylic acids

US4602096A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Michael Karrenbauer · Radolfzell, DE
• Axel Kleemann · Hanau, DE

Key dates

• Filing date: Aug 12, 1985
• Grant date: Jul 22, 1986
• Expiry date: Aug 12, 2005

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D209/20
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

N-acetyl-D(L)-.alpha.-aminocarboxylic acids are thermally racemized by melting, adding a small amount of acetic anhydride to the melt and heating to a temperature between the melting temperature and about 210.degree. C. and subsequently quenching the melt with an aqueous alkali metal hydroxide or ammonia solution. The residence time needed for complete racemization depends on the heating temperature of the melt in the manner that the higher the heating temperature the shorter the residence time.