An Ullmann N-arylation/2-amidation cascade by self-relay copper catalysis: one-pot synthesis of indolo[1,2-a]quinazolinones

We have developed a self-relay copper(I)-catalyzed Ullmann N-arylation/2-amidation cascade to form functionalized indolo[1,2-a]quinazolinones in one-pot from easily available indoles with 2-bromobenzamides. This novel transformation features a tandem process of Ullmann-type coupling, activation of indolenine, and 2-amidation in the presence of a single copper catalyst. In addition, among the substituents of indoles at the C3 position, methyl carboxylate could act as an activating group in this Ullmann N-arylation/2-amidation cascade.