Reagent‐Free C−H/N−H Cross‐Coupling: Regioselective Synthesis of N‐Heteroaromatics from Biaryl Aldehydes and NH3

Abstract An unprecedented synthesis of N‐heteroaromatics from biaryl aldehydes and NH 3 through reagent‐free C−H/N−H cross‐coupling has been developed. The electrosynthesis uses NH 3 as an inexpensive and atom‐economic nitrogen donor, requires no oxidizing agents, and allows efficient and regioselective access to a wide range of phenanthridines and structurally related polycyclic N‐heteroaromatic products.