Process for the preparation of chiral &agr;-hydroxycarboxylic acids

US6818423B2 · kind B2 · utility

Assignee

• DSM Fine Chemicals Austria NFG GmbH & Co KG · AT

Inventors

• Herbert Mayrhofer · Linz, AT
• Rudolf Neuhofer · Mittertreffling, AT
• Peter Poechlauer · Linz, AT
• Wolfgang Skranc · Wien, AT
• Irma Wirth · Ansfelden, AT

Key dates

• Filing date: Nov 4, 2002
• Grant date: Nov 16, 2004
• Expiry date: Dec 17, 2022

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07B2200/07
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the preparation of chiral &agr;-hydroxycarboxylic acids: in which R1 is optionally halogen substituted C1-C2-alkyl and R2 is optionally halogen substituted C2-C3-alkyl from a compound: in which R′2 is optionally halogen substituted C2-C3-alkylene, m is 0 or 1 and R is optionally substituted alkyl, aryl, heteroaryl or heterocyclyl and X can be oxygen, sulfur, sulfinyl, sulfonyl, imino, C1-C6-alkylimino, xanthate, silyl, or, if m is equal to 0, halogen,which is reacted in the presence of a cyanide group donor to give the corresponding (R)- or (S)-cyanohydrin or its racemate: which then is converted by means of acidic hydrolysis into an acid: or its racemate, and by cleavage of the group:(R)m-X  (V), andoptional resolution, whereby the desired chiral &agr;-hydroxycarboxylic acid of the formula (I) is obtained.