Preparation of mixtures of (R)- and (S)-2-(4-alkanoylphenoxy)- or (R)- and (S)-2-(4-aroylphenoxy)propionic esters

US5801272A · kind A · utility

Assignee

• BASF SE

Inventors

• Wolfgang Siegel · Schifferstadt, DE
• Hubert Sauter · Mannheim, DE
• Gerhard Schaefer · Heidelberg, DE

Key dates

• Filing date: Aug 11, 1995
• Grant date: Sep 1, 1998
• Expiry date: Aug 11, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C67/293
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A mixture of (R)- and (S)-2-(4-alkanoylphenoxy)- or (R)- and (S)-2-(4-aroylphenoxy)propionic esters I ##STR1## with an enantiomeric excess of at least 90% is prepared by reacting a mixture of (R) and (S) enantiomer of a 2-phenoxypropionic ester II ##STR2## in which the appropriate (R) or (S) isomer is present in excess, with a carboxylic acid derivative of the formula III EQU R.sup.1 --CO--X III, (X=OH, halogen, R.sup.1 COO or sulfonyloxy) in the presence of a Friedel-Crafts catalyst. The (R)- or (S)-2-(4-alkanoylphenoxy)propionic esters and (R)- or (S)-2-(4-hydroxyphenoxy)propionic esters are used for preparing crop protection agents and drugs.