Chiral bidentate bis(n-heterocyclic carbene)-based palladium complexes bearing carboxylate ligands: highly effective catalysts for the enantioselective conjugate addition of arylboronic acids to cyclic enones

Abstract

Axially chiral cis-chelated bidentate bis(N-heterocyclic carbene)-palladium(II) complexes with two weakly coordinating carboxylate ligands are effective catalysts for the asymmetric conjugate addition of arylboronic acids to cyclic enones, producing the corresponding adducts in moderate-to-high yields and with good-to-high enantioselectivities, in most cases under mild conditions.