Highly enantioselective dynamic kinetic resolution of 1,2-diarylethanols by a lipase-ruthenium couple

A practical procedure has been developed for the dynamic kinetic resolution of 1,2-diarylethanols. This procedure employs a highly enantioselective lipase from Pseudomonas stutzeri (trade name, lipase TL) as the resolution catalyst and a ruthenium complex as the racemization catalyst. Sixteen 1,2-diarylethanols have been efficiently resolved to provide their acetyl derivatives with good yields (95-97%) and high enantiomeric excesses (96-99%).