Copper-Catalyzed Three-Component Cascade Annulation for Divergent Syntheses of Imidazoles and Dihydroimidazoles

The first example of divergent N-heterocycle syntheses through a copper-catalyzed three-component reaction of α,β-unsaturated ketoximes, paraformaldehyde, and amines has been documented. In particular, this divergent synthetic strategy was achieved by controlling the reaction conditions to afford the corresponding imidazoles and dihydroimidazoles in moderate to good yields with a broad substrate scope and good functional group compatibility.