Chiral Rh(III)-Catalyzed Enantioselective Intramolecular Hydroarylation of Enaminone

Abstract

An enaminone has been utilized as a coupling partner in the chiral cyclopentadienyl rhodium(III)-catalyzed enantioselective synthesis of tetrahydro-β-carboline derivatives in high yield and enantioselectivity via an intramolecular hydroarylation reaction of enaminone-tethered indole derivatives. The reaction works under mild conditions with low catalyst/additive loading, demonstrates broad functional group tolerance, and offers excellent stereoselectivity independent of the enaminone’s stereochemistry. Synthetic application, preliminary mechanistic investigation, and a plausible mechanism have also been revealed.