Iron-Catalyzed Regioselective α‑C–H Alkylation of <i>N</i>‑Methylanilines: Cross-Dehydrogenative Coupling between Unactivated C(sp³)–H and C(sp³)–H Bonds via a Radical Process

The iron-catalyzed α-C–H alkylation of N-methylanilines without any directing group by cross-dehydrogenative coupling between unactivated C­(sp3)–H and C­(sp3)–H bonds has been established for the first time, which provides a good complement to C­(sp3)–H activation reactions and expands the field of Fe-catalyzed C–H functionalizations. Many different C­(sp3)–H bonds in cyclic alkanes, cyclic ethers, and toluene derivatives can be used as coupling partners. Mechanistic investigations including the radical reaction process, the main role of various reagents, and the kinetic isotope effect experiment were also described.