Rhodium(III)-Catalyzed <i>N</i>‑Nitroso-Directed C–H Olefination of Arenes. High-Yield, Versatile Coupling under Mild Conditions

<i>N</i>-Nitroso compounds are a versatile class of organic structures that allow expedient access to a diversity of synthetically useful architectures through demonstrated reactivities. We report herein the development of a Rh­(III)-catalyzed <i>N</i>-nitroso-directed methodology for the <i>ortho</i>-olefination of arenes. The heightened reactivity endowed by the <i>N</i>-nitroso group translates to mild reaction conditions, high reaction yields, and synthetic compatibility of otherwise elusive substrates (e.g., an unactivated olefin, 1-octene). Comprehensive mechanistic studies on the electronic effect, deuterium exchange, kinetic isotope effect, kinetic profile, and numerous Rh­(III) complexes have established [RhCp*]²⁺ as the catalyst resting state, electrophilic C–H activation as the turnover-limiting step, and a five-membered rhodacycle as a catalytically competent intermediate. The ability to elaborate the <i>N</i>-nitroso moiety to an amine functionality provides a seminal example of the innumerable synthetic possibilities offered by this transformable directing group