Deprotonation and Subsequent Functionalization of Methyl Groups in Cationic Ruthenium Triple-decker Complexes

The cationic complex [(η-C₅Me₅)Ru(μ,η-C₅Me₅)Ru(η-C₅Me₅)]⁺ undergoes deprotonation of the terminal ring methyl groups on treatment with BuⁿLi-Bu’OK at – 78°C in tetrahydrofuran; subsequent treatment with EX reagents gives rise to functionalized complexes [(η-C₅Me₅)Ru(μ,η-C₅Me₅)Ru(η-C₅Me₄CH₂E)]⁺ (E = Me, Me₃Si, EtS).