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.

A FeCl2‐catalyzed homocoupling of α,β‐unsaturated ketoximes in batch and flow is reported. This protocol demonstrates broad substrate scope and functional group tolerance, providing an alternate route toward the synthesis of 2,4,6‐trisubstituted pyrimidines under mild conditions. Also a gram‐scale reaction has been performed to evaluate the applicability of this method.