TG-MS and TG-FTIR studies of imidazole-substituted coordination compounds: Co(II) and Ni(II)-complexes of bis(1-methylimidazol-2-yl)ketone

Co(II) and Ni(II) coordination compounds with bis(1-methylimidazol-2-yl)ketone (BIK) of general formula M(BIK)(2)X-2 (M = Co or Ni: X = Cl or NO3) were synthesized and characterized by elemental analysis, by UV-vis and FTIR spectroscopies. Following our previous thermoanalytical studies on imidazole-substituted coordination compounds, the thermal behavior of the synthesized complexes was investigated by TG and DTG techniques: the thermal profile is always characterized by three substantial consecutive releasing steps for all the three complexes and the releasing supposed behavior is confirmed by EGA analysis (TG-MS and TG-FTIR). In particular, the first step is ascribed to the release of the two anions, followed by the loss of four methyl groups (side chains of the ligand) and two bridge-carbonyl groups. The residual Cobalt or Nickel tetra-imidazole complex decomposes in a final step to give the metal oxide as the final residue. (C) 2012 Elsevier B.V. All rights reserved.