Iodine-imine Synergistic Promoted Povarov-Type Multicomponent Reaction for the Synthesis of 2,2'-Biquinolines and Their Application to a Copper/Ligand Catalytic System.

An efficient iodine-imine synergistic promoted Povarov-type multicomponent reaction was reported for the synthesis of a practical 2,2'-biquinoline scaffold. The tandem annulation has reconciled iodination, Kornblum oxidation, and Povarov aromatization, where the methyl group of the methyl azaarenes represents uniquely reactive input in the Povarov reaction. This method has broad substrate scope and mild conditions. Furthermore, these 2,2'-biquinoline derivatives had been directly used as bidentate ligands in metal-catalyzed reactions.