Supramolecular structures in [Ag(dppf)] complexes [dppf = 1,1′-bis(diphenylphosphanyl)ferrocene] stabilized by coordinatively versatile trifluoroacetate (TFA) ligands

Abstract

The interaction of silver(I) trifluoroacetate and dppf in different molar equivalents has led to the isolation of dinuclear complexes [Ag 2(μ-O2CCF3)2(μ-dppf)] (1) and [Ag2(η1-O2CCF3) 2(dppf)2] (2). Treatment of 1 with excess dppf gave a coordination polymeric compound [Ag(η2-O2CCF 3)(dppf)]n (3). Reaction of 1 with PMe2Ph in MeOH in the presence of NH4PF6 led to displacement of trifluoroacetate, forming the mononuclear compound [Ag(PMe2Ph) 2(η2-dppf)]PF6 (4). All compounds have been characterized by microanalytical and spectroscopic analyses [IR, MS and NMR (1H, 19F and 31P{1H})] as well as X-ray diffraction studies. Molecular structures of the solvates of 1, viz. 1A (1·0.5THF) and 1B (1·0.5CH2Cl2), 2 and 3 show that they contain trifluoroacetate in bridging, monodentate and bidentate bonding modes, respectively, with dppf as a bridging co-ligand. Compound 3 is an infinite linear [-dppf-Ag-dppf-Ag-dppf-Ag-]n coordination polymer. Interestingly, 1A and 1B form two different supramolecular network structures through C-H⋯F and C-H⋯O hydrogen-bonding interactions. Such secondary bonding interactions also lead to the formation of a 3D supramolecular structure in 3. © Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.