The effect of co-ligands and hydrogen bonds on the structural topology of copper-based complexes: Synthesis and structural characterizations

In order to investigate the influence of intermolecular hydrogen bonds and the co-ligands [WS4]2− and Imt on the structures of copper complexes, two new compounds, [WS4Cu3I(tdmpp)]4·2CH3CN (1) and [CuCl(Imt)·0.5tdmpp]2·2(CH3)2CO (2), have been synthesized in one pot reactions. The reaction of CuI and (NH4)2WS4 with tdmpp (1,1,3,3-tetrakis(3,5-dimethyl-1-pyrazole)propane) (molar ratio = 3:1:1) in DMF/CH3CN (1:4; v/v) led to the formation of complex 1, while treatment of Imt (imidazolidine-2-thione) and CuCl with tdmpp (molar ratio = 2:2:1) in acetone formed complex 2. These complexes have been structurally characterized by X-ray crystallography, infrared spectroscopy and elemental analyses. Thermal analysis and UV–Vis spectroscopic analysis of complex 1 have also been undertaken. Complex 1 has a tetrameric structure which forms intermolecular C–H⋯S and C–H⋯I hydrogen bonds, resulting in a 2D polymeric structure. In this complex, the copper(I) atoms have two different geometries: trigonal planar (CuS2I) and distorted tetrahedral (CuS2N2). In contrast, complex 2 has a dimeric structure in which the copper atoms are four-coordinate with a distorted tetrahedral CuN2SCl geometry. The dimeric molecules link to the oxygen atoms of uncoordinated acetone molecules through N–H⋯O hydrogen bonds.

Graphical abstractTwo new copper(I) based complexes, namely [WS4Cu3I(tdmpp)]4·2CH3CN (1) and [CuCl(Imt)·0.5tdmpp]2·2(CH3)2CO (2), have been synthesized by a one pot reaction. Complex 1 displays a tetramer framework in which the copper(I) atoms have two different geometries: trigonal planar and distorted tetrahedral. Complex 2 has a dimeric structure in which the copper atoms are four-coordinate with a distorted tetrahedral geometry.Figure optionsDownload full-size imageDownload as PowerPoint slide