Lewis acid catalyzed formation of tetrahydroquinolines via an intramolecular redox process

Abstract

Polycyclic tetrahydroquinolines were prepared by an efficient Lewis acid catalyzed 1,5-hydride shift, ring closure sequence. Gadolinium triflate was identified as a catalyst that is superior to scandium triflate as well as other Lewis acids. An approach toward a catalytic enantioselective variant is also described.