Oxidation of some prochiral 3-substituted cyclobutanones using monooxygenase enzymes: a single-step method for the synthesis of optically enriched 3-substituted γ-lactones

Oxidation of the prochiral cyclobutanones 1–5 using Acinetobacter calcoaceticus NCIMB 9871 and Pseudomonas putida NCIMB 10007 monooxygenases (MO1 and MO2) furnishes the corresponding lactones 6–10 in moderate to excellent yield and enantiomeric purity. These enzymes show enantiocomplementarity in all but one case.