Highly stereoselective bioreduction and one-way isomerization of 2-alkyl-4,4,4-trichloro-2-butenals

This article describes a highly stereoselective bioreduction of 2-alkyl-4,4,4-trichloro-2-butenals (1a: Me, 1b: Et) mediated by baker's yeast (Saccharomyces cerevisiae). The E-isomers were regiospecifically converted into the saturated alcohols 2 with high enantioselectivity, whereas the Z-isomers generated in situ by a competitive one-way isomerization were reduced only into the corresponding allyl alcohols 3 during the reactions.