Recent advances in photoinduced amidyl radical-mediated remote C(sp3)–H activation via 1,5-hydrogen atom transfer

Abstract

C–H bonds are widely present in organic molecules and play a crucial role in chemical diversification. Among them, the functionalization of unactivated C(sp³)–H bonds is highly challenging. The 1,5-hydrogen atom transfer (1,5-HAT) strategy offers an avenue for the functionalization of remote inert C–H bonds with excellent regioselectivity and chemoselectivity. This review looks back at the history and mechanism of the Hofmann–Löffler–Freytag (HLF) reaction and highlights the recent advances in the functionalization of remote inert C(sp³)–H bonds triggered by nitrogen-centered radicals (NCRs) via photoinduced 1,5-hydrogen atom transfer processes.