Two novel heterometallacrowns: syntheses and crystal structures of two copper(II) complexes with malonate and o-pthalate

Abstract

Two copper(II) sodium(I) coordination compounds of formula [C 16H 12CuNa 2O 10] ( 1) and [C 6H 8CuNa 2O 10] ( 2) were prepared and their structures were characterized by single-crystal X-ray diffraction, IR spectra and thermal analyses. In complex 1, the sodium atom is six coordinated with four carboxylate oxygens from two o-pthalate ligands, another one oxygen atom from one o-pthalate and one water molecule building a distorted octahedron. All the four oxygen atoms in one o-pthalate participate in coordination, two of which bridge one sodium and one copper atoms, with another one bridging two sodium atoms and the fourth coordinating one sodium atom. As for complex 2, the sodium atom is also six-coordinated with tetrakis-monodentate malonate oxygen atoms and two water molecules building a distorted octahedron. For every malonate, three oxygens coordinate out of the total four. Every carboxylate offers an oxygen atom bridging one sodium and one copper atom with the remaining one bridging two sodium atoms. In both cases, each copper atom is in a square planar environment formed by four carboxylate-oxygens from four o-pthalates and two malonates respectively. The IR spectra also testify the structure detection. Thermal analyses of the two complexes were also carried out.