Enzymatic resolution by CALB of organofluorine compounds under conventional condition and microwave irradiation

Abstract

Enzymatic kinetic resolution of organofluorine rac-alcohols by CALB yielded (-)-(R)-2,2,2-trifluoro-1-phenylethanol (2a), (-)-(R)-1-(3-bromophenyl)-2,2,2-trifluoroethanol (2b), (-)-(R)-1-(4-bromophenyl)-2,2,2-trifluoroethanol (2c), (-)-(S)-1-(2,4,5-trifluorophenyl)ethanol (2d), (+)-(S)-2,2,2-trifluoro-1-phenylethyl acetate (3a), (+)-(S)-1-(3-bromophenyl)-2,2,2-trifluoroethyl acetate (3b), (+)-(S)-1-(4-bromophenyl)-2,2,2-trifluoroethyl acetate (3c) and (+)-(R)-1-(2,4,5-trifluorophenyl)ethyl acetate (3d) in high enantiomeric excess (up to >99% ee). the reactions were conducted under conventional conditions (orbital shaking) and microwave irradiation in toluene and vinyl acetate as acylating agent. the CALB showed excellent selectivities and good yields in the transesterification of fluorinated aromatic compounds. (C) 2013 Elsevier B.V. All rights reserved.