Aniline Dearomatization and Silver-Catalyzed [3+3] Dipolar Cycloaddition: Efficient Construction of Oxocino[4,3,2-cd]indoles from 2-Alkynylanilines and 2-Alkynylbenzaldoximes

Abstract

2-Alkynylanilines are attractive starting materials in indole synthesis because of their ready availability. Herein, a one-pot stepwise procedure is reported for efficient construction of multisubstituted oxocino[4,3,2-cd]indoles from 2-alkynylanilines and 2-alkynylbenzaldoximes. The method comprises the oxidative dearomatization of 2-alkynylanilines, the silver-catalyzed [3+3] cycloaddition with 2-alkynylbenzaldoximes, and subsequent thermal radical skeletal rearrangement and aromatization.

Keywords: cycloaddition; heterocycles; rearrangements; silver; synthetic methods.