Enantioselective insertion of vinyl diazoacetates into O–H bonds of carboxylic acids

Abstract

A highly regio- and enantioselective insertion of vinyl diazoacetates into O–H bonds of carboxylic acids has been realized by cooperative catalysis of an achiral rhodium complex and a chiral phosphoric acid. The insertion reaction exhibits highly carbenic reactivity rather than vinylogous reactivity, representing a rare example towards α-acyloxyl-β,γ-unsaturated esters, and the corresponding esters were obtained in good yields with good enantioselectivities (up to 97% ee).