Preparation of alkyl (R)-(−)-3-hydroxybutyrate by acidic alcoholysis of poly-(R)-(−)-3-hydroxybutyrate

An efficient method for the preparation of optically active alkyl (R)-(−)-3-hydroxybutyrates by chemical depolymerization of biopolymer, poly-(R)-(−)-(3-hydroxybutyrate), was established. This method consists of simple recovery of poly-(R)-(−)-(3-hydroxybutyrate) from bacterial cells followed by acidic alcoholysis. When poly-(R)-(−)-(3-hydroxybutyrate) was purified by a simple digestion method that used 0.2 N sodium hydroxide, alkyl (R)-(−)-hydroxybutyrates were most efficiently produced by alcoholysis with anhydrous hydrochloric acid.