| 摘要 |
PURPOSE:To industrially and advantageously obtain the titled compound useful as a raw material for agricultural chemicals, etc., by asymmetrically hydrolyzing a racemic cyclopentenone ester with a microbial enzyme, converting the hydrolyzate into an optically active ester using an aliphatic carboxylic acid and asymmetrically hydrolyzing the ester with a microbial enzyme. CONSTITUTION:A racemic cyclopentenone ester expressed by formula I (R' is alkyl or alkenyl which may be substituted by halogen; R is 1-7C straight- chain alkyl, alkenyl, etc.) is asymmetrically hydrolyzed with a microbial enzyme to isolate an optically active substance containing >=90% (R) isomer of 4- hydroxycyclopentenone expressed by formula II, which is reacted with an aliphatic carboxylic acid halide or acid anhydride to afford an optically active cyclopentenone ester expressed by formula III. The resultant ester expressed by formula III is then asymmetrically hydrolyzed with a microbial enzyme to give the aimed optically active 4-hydroxycyclopentenone containing >=97% (R) isomer of the compound expressed by formula II. |
