Asymmetric Reduction of Ethyl 4-Chloro-3-oxobutanoate to Ethyl ( S)-4-Chloro-3-hydroxybutanoate Catalyzed by Aureobasidium pullulans in an Aqueous/Ionic Liquid Biphase System

• Published in: Chinese journal of catalysis Vol. 29; no. 6; pp. 577 - 582
• Main Authors: ZHANG, Fan, NI, Ye, SUN, Zhihao, ZHENG, Pu, LIN, Wenqing, ZHU, Po, JU, Nianfeng
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.06.2008
• Subjects: asymmetric reduction; Aureobasidium pullulans; ethyl ( S)-4-chloro-3-hydroxybutanoate; ethyl 4-chloro-3-oxobutanoate; ionic liquid; whole cell; ionic liquid; ethyl 4-chloro-3-oxobutanoate; asymmetric reduction; whole cell; ethyl ( S)-4-chloro-3-hydroxybutanoate; Aureobasidium pullulans
• ISSN: 1872-2067; 1872-2067
• DOI: 10.1016/S1872-2067(08)60051-0

The asymmetric reduction of ethyl 4-chloro-3-oxobutanoate (COBE) to ethyl ( S)-4-chloro-3-hydroxybutanoate (( S)-CHBE) catalyzed by Aureobasidium pullulans CGMCC 1244 was performed in an aqueous/ionic liquid biphase system to improve the productivity and optical purity of ( S)-CHBE. The influences of reaction parameters such as shaking rate, phase volumetric ratio, reaction temperature, initial substrate concentration, and pH were studied. In the aqueous/[bmim]PF 6 biphase system and under the optimum reaction conditions of 30 °C, pH 6.6, rotation speed 180 r/min, and reaction time of 8 h, the conversion of COBE, the enantiomeric excess, and the concentration of ( S)-CHBE were 95.6%, 98.5%, and 47.1 g/L, respectively. When the substrate was fed in batches under the condition of pH 6.6, the accumulated product concentration could reach up to 75.1 g/L.