LIPASE-CATALYZED OPTICAL RESOLUTION OF 2,2,2-TRIFLUORO-1-(INDOLE-3-)ETHANOLS IN ORGANIC-SOLVENTS

As a result of screening 19 enzymes, lipase AK (a lipase from Pseudomonas sp.) was found to be suitable for the optical resolution of 2,2,2-trifluoro-1-(indole-3-)ethanol (TFIE). The combination of two lipase AK-catalyzed reactions gave S-(+)-TFIE and R-(-)-TFIE with 97% e.e. and 95% e.e., respectively. The conditions determined as optimum for the reactions were in octane at 45-degrees-C for 8 h, and using vinyl acetate for acetylation and using propanol for alcoholysis. In cases of TFIEs with a methyl group on the indole nucleus, the enantioselectivity of lipase AK increases when the methyl group is far from the chiral center.