Metal‐Free Dehydrogenation of N‐Heterocycles by Ternary h‐BCN Nanosheets with Visible Light

Abstract An efficient metal‐free catalytic system has been developed based on hexagonal boron carbon nitride ( h ‐BCN) nanosheets for the dehydrogenation of N‐heterocycles with visible light; hydrogen gas is released in the process, and thus no proton acceptor is needed. This acceptorless dehydrogenation of hydroquinolines, hydroisoquinolines, and indolines to the corresponding aromatic N‐heterocycles occurred in excellent yield under visible‐light irradiation at ambient temperature. With h ‐BCN as the photocatalyst and water as the solvent, this environmentally benign protocol shows broad substitution tolerance and high efficiency.