Rhodium/copper-cocatalyzed coupling-cyclization of o-alkenyl arylisocyanides with vinyl azides: one-pot synthesis of α-carbolines

Abstract

A novel rhodium/copper-cocatalyzed coupling–cyclization reaction of o-alkenyl arylisocyanides with vinyl azides has been developed for the first time. In this transformation, the reactive vinyl carbodiimides generated in situ from the coupling reaction of o-alkenyl arylisocyanides with vinyl azides undergo intramolecular [4 + 2] cycloaddition and provide a new and efficient strategy for the synthesis of polysubstituted α-carbolines by the formation of two C–C bonds, one C–N bond and two aromatic rings in a single step from readily available acyclic starting materials.