Enantioenriched Allyl Esters via Lipase-Vanadium Combo Catalysis

Significance

In this paper, the authors report the regio- and enantioconvergent transformation of racemic allylic alcohols into allylic esters using a combination of vanadium catalysts and Candida antarctica lipase B; the former continuously racemizes the substrate, whereas the latter provides chemo- and enantioselective esterification. This approach has been previously reported by this group (S. Akai et al. Angew. Chem. Int. Ed. 2006, 45, 2592); however, unsymmetrical substitution in the 3-position of allylic alcohols was not tolerated. This study reports the system which overcomes these limits. Excellent enantioselectivities (up to >99% ee) were accompanied by good to excellent yields (70-99%).