In the field of radical chemistry, N-radicals are a class of versatile intermediates, and have found wide applications for construction of various C-N bonds, especially the N-heterocycles. However, because of the high bond dissociation free energy of the N-H bond, the generation of N-radicals from N-H bonds and their synthetic potential are still underexplored.

   In fact, in nature, the generation of radicals are always enabled at very mild conditions. For example, the BLUF domain is a small, light-sensitive protein, and it can activate the phenol moiety by H-bonding and transform O-H bond into oxygen-radical at room temperature under visible light irradiation. Inspired by this catalytic mode, we proposed an idea of oxidative deprotonation electron transfer to generate N-radicals. Compared to the traditional methods, we hope that this approach would lower the activation free energy.

   By employing this method, we developed a series of radical cyclization reactions for construction of five- and six-membered N-heterocycles.