Dinuclear platinum(II) complexes containing ferrocenylalkyl–thiolate and –selenolate ligands

Abstract

Alkylation reactions of [Pt₂(μ-S)₂(PPh₃)₄] with haloalkylferrocenes FcCH₂Cl, Fc(CH₂)₆Br and Fc(CH₂)₁₁Br [Fc = (η⁵-C₅H₅)Fe(η⁵-C₅H₄)] gave the cationic μ-thiolate complexes [Pt₂(μ-S){μ-S(CH₂)nFc}(PPh₃)₄]⁺ (n = 1, 6, 11), isolated as PF₆⁻ and/or BPh₄⁻ salts, and characterised by ESI mass spectrometry, NMR spectroscopy, microelemental analysis, and by an X-ray structure determination on [Pt₂(μ-S){μ-SCH₂Fc}(PPh₃)₄]PF₆. The complex contains the typical folded {Pt₂(μ-S)₂} core with an axial ferrocenylmethylthiolate ligand. The corresponding selenolate complex [Pt₂ (μ-Se){μ-SeCH₂Fc}(PPh₃)₄]⁺ was similarly obtained by alkylation of [Pt₂(μ-Se)₂ (PPh₃)₄] with FcCH₂Cl, and isolated as PF₆⁻ and BPh₄⁻ salts. The attempted liberation of FcCH₂SH from [Pt₂(μ-S){μ-SCH₂Fc}(PPh₃)₄]+ using Na₂S was not successful.