Rh-Catalyzed C–H Amination/Annulation of Acrylic Acids and Anthranils by Using −COOH as a Deciduous Directing Group: An Access to Diverse Quinolines

Abstract

A method for the synthesis of diverse polysubstituted quinolines from readily available acrylic acids and anthranils has been developed. The weakly coordinating -COOH directing group, which can be tracelessly removed in the cascade cyclization, is essential for this reaction. Diverse polysubstituted quinolines were obtained under mild reaction conditions with simple H₂O and CO₂ as byproducts. More importantly, 1,2,3,4-tetrahydroacridine, which is the core skeleton of tacrine (an Alzheimer's disease drug), was conveniently synthesized.