N-Heterocyclic carbene-copper(I) complexes in homogeneous catalysis

N-Heterocyclic carbenes (NHCs) have become increasingly popular as ligands for transition metals, thanks to their remarkable successes in metathesis and cross-coupling areas. Important advances have also been achieved in organocopper chemistry. To date, the reported neutral N-heterocyclic carbene-copper(I) complexes have shown outstanding catalytic activity. In this account, we describe the application of such complexes in a variety of organic transformations.