Synthesis, spectroscopic, thermal and structural properties of Cu(II) complexes of unsaturated carboxylic acids

In this work, [Cu(aa)2(2-Meim)2] (1), [Cu(maa)2(2-Meim)2] (2), [Cu(aa)2(2-IPim)2] (3) and [Cu(maa)2(2-IPim)2] (4) complexes were synthesized by using methacrylic acid (MaaH) and acrylic acid (aaH) as the anionic ligand, 2-methylimidazole (2-Meim) and 2-isopropylimidazole (2-IPim) as neutral ligand. Compositions of complexes were determined by elemental analysis. Spectroscopic (UV-VIS, IR), magnetic and thermal properties were investigated. Structures of 2, 3 and 4 complexes were illuminated by X-ray single crystal diffraction method. The spin magnetic moments were calculated from the magnetic susceptibility measurements of the complexes at the room temperature. All Cu (II) complexes were paramagnetic because they had a single electron unmatched in the d9 structure. The thermal degradation behaviors of the complexes were investigated by TG, DTG and DTA techniques. According to the thermal analysis datas it has been observed that imidazole and aqua ligands removed in the first degradation step of the complexes, then the anionic ligands removed and the metal oxides are formed as final decomposition products. X-ray single crystal datas of the synthesized complexes [Cu(maa)2(2-Meim)2], [Cu(aa)2(2-IPim)2] and [Cu(maa)2(2-IPim)2] show that the coordination geometries of the central atoms are square plane, octahedral and distorted octahedral respectively.