Mechanistic insights into photocatalytic nitrene transfer reactions of benzoyl azide in the presence of phosphoric acid

Abstract

Computational studies were carried out to shed light on the mechanism of photocatalytic nitrene transfer reactions of benzoyl azide in the presence of phosphoric acid. The formed H-bonding complex of benzoyl azide with H₃PO₄ would readily undergo single electron reduction with the excited *Ru(II) photocatalyst, followed by sequential proton transfer and N₂ dissociation to give a key N-centered radical. The energy transfer mechanistic pathway leading to a protonated nitrenium species, however, might not be feasible. The formed N-radical underwent different types of reactions with N-methylpyrrole and alkene, respectively, which was also rationalized.