Asymmetric Synthesis of(S)-3-Chloro-1-phenylpropanol with Immobilized Acetobacter sp. CCTCC M209061 Cells in a Monophasic System

Optically pure 3-chloro-1-phenyl-1-propanol is an important intermediate for the synthesis of drugs for treating depression. In the present study, biocatalytic asymmetric reduction of 3-chloropropiophenone to(S)-3-chloro-1-phenyl-1-propanol with immobilized Acetobacter sp. CCTCC M209061 cells was successfully conducted in a monophasic aqueous system with high efficiency and selectivity. The immobilized Acetobacter sp. CCTCC M209061 cells exhibited higher stabilities(thermal, p H, and operational stability) than the free cells. In addition, the immobilized microbial cells exhibited a relatively good recyclability; the relative activity of immobilized cells remained over 80%, while that of the free cells under the same condition was less than 20%. In the studied system, glucose was the best co-substrate at an optimum concentration of 50 mmol/L. The optimum buffer p H, reaction temperature, and substrate concentration in this reaction system were 5.5, 30 ℃, and 3.0 mmol/L, respectively. Under the optimized reaction conditions, the initial reaction rate, yield, and product e.e. were 1.77 m M/h, 88.9%, and above 99.0%, respectively.