Bifunctional organocatalyst for methanolytic desymmetrization of cyclic anhydrides: increasing enantioselectivity by catalyst dilution

Abstract

Highly enantioselective methanolysis of meso-cyclic anhydride was achieved with bifunctional organocatalyst containing a quinine-thiourea moiety; unusual concentration, temperature and solvent effects on the enantioselectivity can be explained in terms of a mechanism involving monomer-dimer equilibration of the catalyst.