Three-Component Ring-Expansion Reaction of Indoles Leading to Synthesis of Pyrrolo[2,3-<i>c</i>]quinolines

Abstract

Herein, we have developed an atom- and step-economic three-component cascade reaction that enables a modular platform for the synthesis of pyrrolo[2,3-<i>c</i>]quinoline compounds through ring-expansion/cyclization by way of novel N1-C2 cleavage of indoles. The metal-free catalytic system exhibits a broad functional group tolerance.