Dual Roles of tert ‐Butyl Nitrite in the Transition Metal‐ and External Oxidant‐Free Trifluoromethyloximation of Alkenes

By employing tert ‐butyl nitrite as both nitrogen source and oxidant, the trifluoromethyloximation of alkenes proceeds smoothly in a free‐radical process. The developed difunctionalization reaction enables practical and efficient synthesis of a wide range of α‐CF 3 ketoximes in moderate yields with excellent regioselectivity. This method features the use of readily available and stable alkenes as substrates and inexpensive CF 3 SO 2 Na as a CF 3 reagent, no involvement of transition metals or external oxidant, and room‐temperature conditions. Moreover, a scale‐up of the reaction, further transformation of the products into various valuable CF 3 ‐containing compounds, and removal of the trifluoromethyl group are readily achieved.