Production of chiral alcohols from prochiral ketones by microalgal photo-biocatalytic asymmetric reduction reaction.
Microalgal photo-biocatalysis is a green technique for asymmetric synthesis. Asymmetric reduction of nonnatural prochiral ketones to produce chiral alcohols by microalgal photo-biocatalysis was studied in this work. Acetophenone (ACP) and ethyl acetoacetate (EAA) were chosen as model substrates for aromatic ketones and β-ketoesters, respectively. Two prokaryotic cyanophyta and two eukaryotic chlorophyta were selected as photo-biocatalysts. The results proved that nonnatural prochiral ketones can be reduced by microalgal photo-biocatalysis with high enantioselectivity. Illumination is indispensable to the photo-biocatalysis. For aromatic ketone, cyanophyta are eligible biocatalysts. For ACP asymmetric reduction reaction, about 45% yield and 97% e.e. can be achieved by the photo-biocatalysis reaction with Spirulina platensis as biocatalyst. On the contrary, chlorophyta are efficient biocatalysts for β-ketoester asymmetric reduction reaction among the four tested algae. For EAA asymmetric reduction reaction, about 70% yield and 90% e.e. can be achieved with Scenedesmus obliquus as biocatalyst. The microalgae used in this study outperformed other characterized biocatalysts such as microbial and plant cells.
College of Chemical Engineering and Technology, Wuhan University of Science and Technology, No. 154 Postal Box, Wuhan 430081, China. yangzh@wust.edu.cn
Zhong-Hua
ZH
Yang
Li
L
Luo
Xu
X
Chang
Wei
W
Zhou
Geng-Hua
GH
Chen
Yan
Y
Zhao
Ya-Jun
YJ
Wang
D000090:Acetoacetates / Q000378:metabolism; D000098:Acetophenones / Q000378:metabolism; D000438:Alcohols / Q000138:chemical synthesis*; D055162:Biocatalysis; D000460:Chlorophyta / Q000378:metabolism*; D000458:Cyanobacteria / Q000378:metabolism*; D007218:Industrial Microbiology; D007659:Ketones / Q000378:metabolism; D058086:Microalgae / Q000378:metabolism*; D055668:Photochemical Processes
D000090:Acetoacetates; D000098:Acetophenones; D000438:Alcohols; D007659:Ketones; C024840:ethyl acetoacetate; C038699:acetophenone