Metal- and photocatalyst-free benzylic C–H halogenation <i>via</i> an electron donor–acceptor complex

Here, we report a metal- and photocatalyst-free benzylic C-H halogenation (Cl, Br, F) <i>via</i> an electron donor-acceptor complex between halogenated reagents and trialkylphosphines. This light-promoted method utilizes an electron donor-acceptor complex to generate halogen radicals, and features mild conditions and broad functional group tolerance, enabling late-stage functionalization of complex molecules.