Di- and tetracarboxylic aromatic acids with silane spacers and their copper complexes: Synthesis, structural characterization and properties evaluation

Two polycarboxylic acids, bis(p-carboxyphenyl)diphenylsilane and bis(3,4-dicarboxyphenyl)dimethylsilane, were prepared according to published procedures and characterized, besides elemental and spectral analysis, for the first time by X-ray single crystal diffraction. Their copper(II) complexes were obtained in the presence of 1,10-phenantroline as co-ligand, the crystallographic data revealing the formation of 2D structures through hydrogen bonds. The hydrogen bond dynamics of the copper complexes was studied by FTIR-ATR spectrometry. The thermal stability of the acids and derived copper complexes was evaluated by thermogravimetrical analysis. The moisture uptake capacity and porosity of the complexes were estimated on the basis of the water vapour sorption measurements in dynamic regime. Magnetic measurements performed on the two metal complexes correspond to not interacting copper(II) with S - 1/2 and g factor equal to 2.14 and 2.19 being consistent with pentacoordinated Cu(II) paramagnetic centres. (C) 2014 Elsevier B.V. All rights reserved.