METHOD FOR PRODUCING OPTICALLY ACTIVE (4E)-5-CHLORO-2-ISOPROPYL-4-PENTENOIC ACID OR BASIC AMINO ACID SALT THEREOF

摘要

To provide a method for producing an optically active (4E)-5-chloro-2-isopropyl-4-pentenoic acid, a basic amino acid salt thereof or an optically active (4E)-5-chloro-2-isopropyl-4-pentenoic acid ester with high yield and high optical purity by simple operation. An optically active (4E)-5-chloro-2-isopropyl-4-pentenoic acid is obtained by precipitating a basic amino acid salt of optically active (4E)-5-chloro-2-isopropyl-4-pentenoic acid from a solvent solution containing an optical isomer mixture of (4E)-5-chloro-2-isopropyl-4-pentenoic acid and an optically active basic amino acid or a salt thereof, and then the basic amino acid salt of optically active (4E)-5-chloro-2-isopropyl-4-pentenoic acid is subjected to a desalting reaction. Further, an esterification reaction is carried out to obtain an optically active (4E)-5-chloro-2-isopropyl-4-pentenoic acid ester.