Dynamic kinetic resolution of secondary diols via coupled ruthenium and enzyme catalysis

Enzymatic acylation of secondary symmetrical diols (as meso/dl mixtures) in combination with ruthenium-catalyzed isomerization of the diol led to effi cient dynamic kinetic resolution. In this way, a meso/dl mixture of the dio l was transformed to enantiomerically pure (R,R)-diacetate, making efficien t use of all the diol material. For some of the flexible substrates, substa ntial amounts of meso-diacetates were formed as side products. The results indicate that the major part of the meso product is formed via an intramole cular acyl-transfer pathway.