Amine-Ligated Boryl Radical Enabled Hydrofunctionalization of Styrenes via Halogen-Atom Transfer of Alkyl and Aryl Bromides

Abstract Herein, we demonstrate an amine-ligated boryl radical mediated halogen-atom transfer (XAT) strategy with alkyl and aryl bromides to construct C(sp 3)–C(sp 3) and C(sp 3)–C(sp 2) bonds, respectively. The first step involves the photocatalytic and decarboxylative generation of amine-ligated boryl radicals from a carboxylic acid containing amine-ligated borane. The resulting amine-ligated boryl radical undergoes XAT with organobromides to generate carbon-centered radicals, which react with styrenes to afford hydrofunctionalized products. Furthermore, this photocatalytic XAT strategy can be applied to synthesize gem-difluorostyrene and 1,1-disubstituted cyclopropane through a radical-polar crossover mechanism.