α-Thiophenyl ketones are easily available by the regioselective ring-opening of 1-trifluoromethyl-epoxy ethers with phenyl sodium thiolate. Their in situ reduction with NaBH4, followed by oxidation with NaIO4 and thermal decomposition of the resultant sulphoxides, provided allylic trifluoromethyl alcohols in high overall yield.
Several microorganisms have been employed in the reduction of two α,α,α-trifluoro-α′-sulfenylketones. Some of them produce corresponding alcohols in high diastero- and enantioselection, the high conversion in a single enantiomer being secured by the racemization of starting ketones in the biotransformation conditions. Transformation of obtained sulfenyl-trifluoromethyl-alcohols into trifluoromethyl-epoxides