Light-driven benzylic azolation

Selective activation of C(sp3)–H bonds has been reported by Musacchio et al., who developed a photoredox-catalyzed coupling between benzylic positions and azoles to afford N-benzylated products. Critically, N-alkoxypyridinium salts are used for enabling C(sp3)–H azolation via a combination of hydrogen atom transfer (HAT) and oxidative radical polar crossover (RPC). This platform has been demonstrated with a broad series of heterocycles and various benzylic coupling partners.