Site-Selective Copper-Catalyzed Halogenation at an Unactivated C(sp3)–H Bond: Mechanistic Insights and Advances

Abstract Copper-catalyzed methods for the halogenation of unactivated C(sp3)–H bonds has emerged as a powerful tool in modern chemical synthesis. Their rapid and elegant development has been driven by recent advances in radical and redox chemistry. This account provides an overview of these recent efforts in copper-mediated unactivated C(sp3)–H halogenation strategies that have focused and exploited mechanistic paradigms such as inter- and intra-hydrogen-atom transfer reactions and Cu(I)/Cu(II)/Cu(III) redox cycling.