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

• Two polycarboxylic acids were obtained and for the first time structurally characterized.
• Copper(II) complexes of 1,10-phenantroline were obtained in presence of carboxylic acids.
• 2D networks were formed through hydrogen bonds as crystallographic data revealed.
• The hydrogen bond dynamics was studied by FTIR-ATR spectrometry.
• The thermal stability, moisture and magnetic behaviour of the complexes were evaluated.

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.

New copper(II) complexes were obtained by the reaction of copper salt with bis(p-carboxyphenyl)diphenylsilane or bis(3,4-dicarboxyphenyl)dimethylsilane and 1,10-phenantroline. Magnetic measurements have revealed not interacting copper(II) metal centres. Moisture sorption and thermal behaviour were studied and revealed differences between the two complexes.Figure optionsDownload as PowerPoint slide