Baker’s yeast mediated asymmetric reduction of cinnamaldehyde derivatives

The enantioselective reduction of cinnamaldehyde derivatives is an attractive strategy to prepare various optically active multifunctional molecules that can be used as chiral building blocks for the synthesis of some HIV-protease inhibitors. The asymmetric reduction with pH adjusted to 5.5 of α-substituted-cinnamaldehydes (Br, N3) mediated by baker’s yeast (Saccharomyces cerevisiae) yielded α-substituted-3-phenyl-1-propanol in excellent enantiomeric excesses and yields.