Synthesis of aza- and aza-carba-pterocarpens by electrophilic amination of arene C−H bonds

Tetracyclic fused heterocycles of the aza-pterocarpen type are attracting increasing interest due to their various biological activities. We present a novel and straightforward synthesis of representative aza- and aza-carba-pterocarpens. For the first time, the Grignard-induced electrophilic amination of arene C−H bonds starting with o-nitrobiaryls was applied to this type of compound. • Tetracyclic fused heterocycles of the aza-pterocarpen type are attracting increasing interest. • We present an efficient synthesis of representative aza- and aza-carba-pterocarpens. • The Grignard-induced electrophilic amination of arene C−H bonds starting with o-nitrobiaryls was applied to the synthesis of this type of compound.