A NOVEL GENERATION OF OPTICALLY-ACTIVE ETHYL 4-CHLORO-3-HYDROXYBUTYRATE AS A C4 CHIRAL BUILDING UNIT USING MICROBIAL DECHLORINATION

A novel procedure for the generation of optically active ethyl 4-chlor o-3-hydroxybutyrate using bacterial cells was developed. Ethyl (S)-4-c hloro-3-hydroxybutyrate was prepared by Pseudomonas sp. OS-K-29, which stereoselectively assimilates 2,3-dichloro-1-propanol. The reaction w as based on its kinetic dehalogenation for both enantiomers using the resting cells. The obtained 4-chloro-3-hydroxybutyrate rate had high e nantiomeric excess of >98%, with a yield of 33% at the microbial resol ution step. Moreover, several C4 compounds having the 4-chloro-3-hydro xyl function were also resolved and gave good enantiomeric purities (> 95 %ee). Ethyl (R)-4-chloro-3-hydroxybutyrate was also obtained with h igh enantiomeric purity (>98 %ee) using the cells of Pseudomonas sp DS -K-NR818. Copyright (C) 1996 Elsevier Science Ltd