Reactivity of “Ligand-Free” Au⁺: C–H and C–C Activation versus π Coordination

[(Me₂S)Au]⁺ cations, generated from (Me₂S)AuCl and AgSbF₆ in dichloromethane at 0–20 °C, serve as sources of solvated Au⁺ (alongside unreactive [Au(SMe₂)₂]⁺), which reacts with the methyl-substituted arenes C₆Me_6–nH_n (n = 0–2) with C–H bond cleavage to give the sulfonium salts [C₆Me_5–nH_nCH₂SMe₂]⁺. There was no evidence for arene π coordination to Au⁺ or for the formation of σ-bonded Au–benzyl species. Surprisingly, the reaction of Au⁺ with CH₂Ar₂ leads to C–C bond cleavage (Ar = 2,4,6-C₆H₂Me₃). The reactions are highly selective for benzylic C–H and C–C bonds, whereas metalation of the arene ring is not observed.