Polynuclear Copper(I) Complexes with Chelating Bis- and Tris-N-Heterocyclic Carbene Ligands: Catalytic Activity in Nitrene and Carbene Transfer Reactions

Di- and trinuclear complexes of copper(I) bearing bis- or tris-N-heterocyclic carbene ligands have been prepared and evaluated as catalysts in nitrene transfer reactions from PhI=NTs to unsaturated and saturated substrates (olefin aziridination and C–H bond amidation) and carbene transfer reactions from diazo compounds to olefins. The complexes exhibited moderate-to-high catalytic activity in both processes. The tosylamidation of C–H bonds, previously unreported with a NHC-containing copper catalyst, was promoted by the dinuclear complexes.