One-Pot Synthesis of Furo[3,4-<i>c</i>]indolo[2,1-<i>a</i>]isoquinolines through Rh(III)-Catalyzed Cascade Reactions of 2-Phenylindoles with 4-Hydroxy-2-alkynoates

Abstract

An efficient and regioselective synthesis of fused polycyclic furo[3,4-<i>c</i>]indolo[2,1-<i>a</i>]isoquinolines through Rh(III)-catalyzed cascade C-H activation/annulation/lactonization of 2-arylindoles and 4-hydroxy-2-alkynoates has been developed. This cascade reaction displays high step economy and efficiency and tolerates various functional groups. The titled polycyclic furo[3,4-<i>c</i>]indolo[2,1-<i>a</i>]isoquinolines exhibit fluorescence emission.