Rhodium-Catalyzed Annulation of Tertiary Aniline <i>N</i>‑Oxides to <i>N</i>‑Alkylindoles: Regioselective C–H Activation, Oxygen-Atom Transfer, and <i>N</i>‑Dealkylative Cyclization

[Cp*RhIII]-catalyzed annulation of tertiary aniline N-oxides with alkynes was reported to achieve the challenging ortho C–H functionalization of tertiary anilines via N–O bond acting as a traceless directing group. More significantly, this system represents the first example which integrates C–H activation, oxygen-atom transfer, and N-dealkylative cyclization in one reaction. This unprecedented coupling reaction has allowed the construction of N-alkylindole derivatives in high efficiency with broad substrate scope and good functional group tolerance.