Biomimetic complexes of divalent cobalt and zinc with N-heterocyclic dicarboxylic ligands

• Two biomimetic complexes were precipitated and the thermal behavior was studied.
• Evolved gas analysis by MS allowed to prove the supposed decomposition mechanism.
• The different influences of the reaction atmosphere were proved by the fragmentation pattern.
• On the basis of a previous paper, the compared behavior allows to suggest a thermal decomposition that is not dependent from the central metal ion.

To complete a previous characterization of complexes with a polycarboxylate ligand, imidazole-4,5-dicarboxylic acid (H2imdc), cobalt and zinc complexes with (Himdc)− ligand were synthesized. The precipitated Co(Himdc)2(H2O)2 and Zn(Himdc)2(H2O)2 complexes were characterized and their stability was studied by thermoanalytical techniques coupled to mass spectrometry, to prove their decomposition mechanism by evolved gas analysis (EGA-MS). The results confirmed that the decomposition mechanism, already proposed for the analog copper and nickel complexes, can be assumed as representative for these structures, independently from the central coordinating metal.

Figure optionsDownload as PowerPoint slide