Metal-free graphene oxide-catalyzed aza-semipinacol rearrangement to prepare 2-(indol-2-yl)phenols and benzofuro[3,2-<i>b</i>]indolines containing quaternary carbon centers

Abstract

A metal-free, heterogeneous, inexpensive, and environmentally friendly graphene oxide-catalyzed aza-semipinacol rearrangement was developed to prepare various 2-(indol-2-yl)phenols and benzofuro[3,2-<italic>b</italic>]indolines in good to excellent yields.