Optical resolution of 2,2,2-trifluoro-1-(9-phenanthryl)ethanol via enzymatic alcoholysis of its activated ester

Practical lipase LIP (Pseudomonas aeruginosa)-catalyzed optical resolution of 2,2,2-trifluoro-1-(9-phenanthryl)ethanol (TFPE), which is a sterically hindered secondary alcohol, has been performed. The method was used effectively for the first enzymatic preparation of both enantiomers of TFPE via lipase-catalyzed enantioselective alcoholysis of its chloroacetate ester. A simple procedure was developed for separating the S-alcohol product from the unreactive R-chloroacetate ester and for hydrolyzing the latter to obtain the R-alcohol. Using a similar procedure, the optical resolution of 2,2,2-trifluoro-1-(1-naphthyl)ethanol (TFNE) was achieved as well.