Ferrocene decorated homoleptic silver(I) clusters: Synthesis, structure, and their electrochemical behaviour

Abstract Silver(I) ferrocenyl dithiophosphonato [Ag{S2P(OiPr)Fc}]n I, [Fc = Fe(η5-C5H4)(η5-C5H4)] 1D polymer was yielded via a ligand exchange reaction between silver nanocluster [Ag21(S2P(OiPr2)12)]PF6 and monoanionic [S2P(OiPr)Fc]¯ ligand. As per molecular stoichiometry of 1, a direct reaction between [Ag(CH3CN)4]PF6 and [S2P(OiPr)Fc]− was performed in methanol solvent and surprisingly, generate a tetrahedral Ag4{S2P(OiPr)Fc}4 2 cluster instead of 1. Both (1 and 2) clusters are the novel example of homoleptic Ag(I) complexes supported by ferrocenyl dithiophosphonates. Molecular structure of these clusters was unequivocally established by single crystal X-ray crystallographic analyses and supported by the ESI-MS, and 1H and 31P NMR spectroscopy. Structural elucidations reveal that compound 1 has subsequently Ag2S2 square plane and Ag2S4P2 twisted boat units to build a long chain 1D polymer. The cluster 2 exhibits with a tetrahedral Ag(I) core framed by four [S2P(OiPr)Fc]− ligands. interstingly, the [S2P(OiPr)Fc]− ligand display a trimetallic triconnective (η3; µ1, µ2) bonding pattern in both molecules. The electrochemical behaviours of both compounds (1 and 2) were studied by using cyclic voltammetry, which shows a single wave for all the peripheral ferrocenes and implies negligible electrostatic factor between all ferrocene moieties.