Enantioselective Reduction of Cyclobutenones Using Ene‐Reductases

Abstract Enantioselective reduction of cyclobutenones to optically active cyclobutanones has been achieved by using whole‐cell overexpressing Seqenzym ene‐reductases (EREDs). By using these enzymes, trans ‐cyclobutanones were isolated in good yields and with enantiomeric excesses up to 99%.