Trifluoromethide as a Strong Base: [CF<sub>3</sub><sup>–</sup>] Mediates Dichloromethylation of Nitrones by Proton Abstraction from the Solvent

An unprecedented reactivity of CF<sub>3</sub>-TMS has been revealed, which exploits the basic character of the generated [CF<sub>3</sub><sup>–</sup>] capable of delivering dichloromethide from dichloromethane with subsequent transfer to nitrones under smooth conditions. The proton-abstraction pathway was demonstrated through isotopic labeling experiments in CD<sub>2</sub>Cl<sub>2</sub>. The same reaction was achieved in acetonitrile with the introduction of a cyanomethyl group onto the nitrones.