Abstract A process of highly stereoselective reduction of ethyl 4-chloro-3-oxobutanoate (ECOB) to ethyl (S)-4-chloro-3-hydroxy butanoate [(S)-ECHB] with Baker's yeast was established. The influence of volumetric phase ratio, substrate concentration, the amount of dried yeast cells and glucose on the yield of ethyl (S)-4-chloro-3-hydroxybutanoate and the enantiomeric excess (ee)(S) value were also investigated. A high yield and ee of ethyl (S)- ...
