FeCl3-Catalyzed Stereoselective Construction of Spirooxindole Tetrahydroquinolines via Tandem 1,5-Hydride Transfer/Ring Closure

An efficient FeCl3-catalyzed stereoselective intramolecular tandem 1,5-hydride transfer/ring closure reaction was developed. The method allows for the formation of structurally diverse spirooxindole tetrahydroquinolines in high yields (up to 98%) with good to excellent levels of diastereoselectivity (up to 99:1 dr). The catalytic enantioselective variant of this process was also investigated preliminarily with a chiral BINOL-derived phosphoric acid.