On the mode of Baker's yeast reduction of enantiomeric 4-acyl butanolides

Article abstract of DOI:10.1016/S0040-4020(01)96212-X

4-acyl butanolides (R)-(1a) and (R)-(1b), bearing n-alkyl chains, on yeast treatment afford exclusively the syn reduction products (4a) and (4b), whereas the (S) enantiomers yield syn (2a) and (2b) in ca. 6:4 ratio with the anti diastereoisomers (3a) and (3b), respectively. Under the same conditions, (S)-(1c) give rise to syn and anti reduction products in ca. 1:4 ratios, respectively.