Process for obtaining active L-.alpha.-amino carboxylic acids from corresponding racemic d, L-.alpha.-amino carboxylic acids

US6114163A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Karlheinz Drauz · Alzenau, DE
• Andreas Bommarius · Frankfurt, DE
• Michael Karrenbauer · Radolfzell, DE
• Gunter Knaup · Bruchköbel, DE

Key dates

• Filing date: Jun 16, 1998
• Grant date: Sep 5, 2000
• Expiry date: Jun 16, 2018

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C12P13/04
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The disclosure relates to a process for obtaining optically active L-.alpha.-aminocarboxylic acids from the corresponding racemic D,L,.alpha.-aminocarboxylic acids. The following steps are involved: (a) the D,L,.alpha.-aminocarboxylic acids are acetylated; (b) the N-acetyl-L-.alpha.-aminocarboxylic acid present in the mixture of N-acetyl-D,L,.alpha.-aminocarboxylic acids thus obtained is broken down enzymatically into the L-.alpha.-aminocarboxylic acid; (c) the L-.alpha.-aminocarboxylic acid is separated from the mixture, a quantity of a solution of N-acetyl-D(L)-.alpha.-aminocarboxylic acids and a quantity of acetate equivalent to the L-.alpha.-aminocarboxylic acid being retained; and (d) the N-acetyl-D(L)-.alpha.-aminocarboxylic acid is racemized and recycled for enzymatic breakdown. Known extraction processes involving steps (a) to (d) have the disadvantage of producing large quantities of salt. Specifically, the processes are far removed from the ideal equation, according to which one hundred percent of the acetic anhydride and the D,L,.alpha.-aminocarboxylic acids are converted to L-.alpha.-aminocarboxylic acids and acetic acid. Adjusting the retained solution from step (c) in…