Hydrothermal synthesis of a dinuclear copper(II) complex with 2-aminopyrimidine and bridging oxalate ligands: in situ degradation of tartaric acid to oxalate and thermal decomposition to CuO nanoparticles

A new binuclear copper complex formulated as µ-(C2O4)-bis([Cu(amp)(NO3)(H2O)2] .H2O) (1) has been hydrothermally synthesized by the reaction of Cu(NO3)2 .3H2O with tartaric acid and 2-aminopyrimidine in molar ratio 1:1:1 in water solution. Elemental analyses, spectroscopic methods (IR, UV/Vis), thermal analysis and X-ray diffraction (XRD) studies have been used for characterization of compound 1. An important aspect of the preparation of 1 was in situ degradation of tartaric acid to oxalate. The oxalate ion is bridged between two copper(II) ions and every Cu(II) atom is six coordinated by an O,O′-bidentate oxalate ion, two water molecules, and a nitrogen atom from 2-aminopyrimide. Thermal decomposition of 1 in the presence of polyethylene glycol led to nano-particles of CuO. Powder XRD and scanning electron microscopy (SEM) were used to characterize the structure and morphology of the synthesized powder. The XRD pattern confirmed the formation of CuO tenorite in monoclinic symmetry.