Copper‐Catalyzed Trifluoromethylalkynylation via Radical‐Mediated Multicomponent Process

Multicomponent reactions (MCRs) are powerful tools for the rapid construction of complex molecules, as they enable the assembly of diverse functional fragments into a single skeleton. Herein, we report an efficient and practical copper-catalyzed multicomponent radical process that couples readily available Togni's reagent II, alkenes, and alkynes to afford β-trifluoromethyl propynes with high regioselectivity. Under mild copper-catalyzed conditions, this strategy enables chemoselective and regioselective radical trifluoromethylalkynylation of alkenes while suppressing undesired copper-catalyzed or radical-mediated side reactions. The method exhibits a broad substrate scope for both alkenes and alkynes, with excellent functional group compatibility.