Dinuclear platinum(II) sulfide–thiolate complexes [Pt₂(μ-S)(μ-SR)(PPh₃)₄]⁺ containing fluorinated substituents and the identification of a SC₆F₅ π interaction in the crystal structure of [Pt₂(μ-S)(μ-SCH₂C₆F₅)(PPh₃)₄]BPh₄•2C₆H₆

Abstract

Reactions of the platinum(II) sulfido complex [Pt₂(μ-S)₂(PPh₃)₄] with the alkyl iodides ICH₂CH₂(CF₂)nCF₃ (n = 3, 7) gives good yields of the monoalkylated products [Pt₂(μ-S){μ-SCH₂CH₂(CF₂)nCF₃}(PPh₃)₄]⁺, which were isolated as PF₆⁺or BPH₄⁻ salts, and characterised by ESI mass spectrometry, NMR spectroscopy and elemental analysis. The complex [Pt₂(μ-S){μ-SCH₂CH₂(CF₂)nCF₃}(PPh₃)₄]⁺ appears to have normal reactivity for this type of complex, namely reaction with Ph₃PAuCl to give [Pt₂(μ-SAuPPh₃){μ-SCH₂CH₂(CF₂)nCF₃}(PPh₃)₄]₂⁺, and reaction with Me₂SO₄ to give [Pt₂(μ-SMe){μ-SCH₂CH₂(CF₂)nCF₃}(PPh₃)₄]₂⁺. Reaction of [Pt₂(μ-S)₂(PPh₃)₄] with C₆F₅CH₂Br gave [Pt₂(μ-S)(μ-SCH₂C₆F₅)(PPh₃)₄]⁺, isolated as BPh₄⁻ its salt, and characterised by NMR spectroscopy and a single-crystal X-ray structure determination. The C₆F₅ group lies above the {Pt₂S₂} core of the complex as a result of a SC₆F₅ π interaction, in contrast to the published structure of [Pt₂(μ-S)(μ-SCH₂C₆H₅)(PPh₃)₄]PF₆, where the C₆H₅ group projects away from the {Pt₂S₂} core.