Parallel copper catalysis: diastereoselective synthesis of polyfunctionalized azetidin-2-imines.

An efficient and diastereoselective synthesis of highly functionalized azetidin-2-imines has been achieved through a parallel catalysis strategy, including a copper-catalyzed azide-alkyne cycloaddition, a copper-catalyzed Csp-Csp(2) cross-coupling reaction, and an intermolecular [2 + 2] cycloaddition. The products could be conveniently converted into the structurally interesting dihydroazeto[1,2-a]benzo[e]azepin-2(4H)-imines.