Diastereo- and Enantioselective Assembly of Spirooxindole Tetrahydroquinoline Skeletons through Asymmetric Binary Acid Catalyzed Hydride Transfer–Cyclization

An efficient binary acid catalyzed asymmetric intramolecular tandem 1,5-hydride transfer/ring-closure reaction was achieved. The process is catalyzed by the combination of a chiral spirocyclic phospho­ric acid and magnesium chloride to afford structurally diverse spirooxindole tetrahydroquinolines in good yields with high diastereo- and enantioselectivities.