SHORT CHEMOENZYMATIC SYNTHESIS OF S-ENANTIOMERS OF 2 SYSTEMIC FUNGICIDES

2-Methyl-(4'-tert-butyl)cinnamaldehyde (1) was reduced by Saccharamyce s cerevisiae (baker's yeast) to S-3-(4'-tert-butyl)-phenyl-2-propanol (4) in high chemical and very high optical yield (e.e. greater than or equal to 99%). Chlorination of 4 to 5, and alkylation of the correspo nding cyclic amines complete this short enantioselective synthesis of peridino)-2-methyl-3-(4'tert-butyl)-phenyl-propane (6) and pholino)-2- methyl-3-(4'-tert-butyl)-phenyl-propane (7), the S-enantiomers of fenp ropidine and fenpropimorph, commercialy important systemic fungicides.