SOME APPLICATIONS OF THERMAL-ANALYSIS TO THE COORDINATION CHEMISTRY

The behaviour of complexes of the type MeD2I2 (Me = Co, D = acetylacetone or benzoylacetone, I = imidazole and derivative in the course of the stepwise thermal degradation is different. In the case of D = acetylacetone in the first step acetylacetone is split off. At D =benzoylacctone the decomposition starts with the partial elimination of the heterocyclic ligands. In beta-position unsubstituted nickelacyclic complexes from type (bipy)Ni(CH2CH2CH2COO) decompose by a reductive elimination and separating of CO2 forming a '(bipy)Ni'-intermediate. A single reductive decoupling is hindered by blocking up the beta-position. Opposite to the high thermal stability of the trimesityl aluminium the intermediates Almes2Cl and AlmesCl2 show with decreasing amounts of mesityl groups and increasing content of halogene, respectively, a significant decreasing thermal stability. The thermal degradation of nickelchelates of alkylsubstituted chinolin-8-ol starts with the dehydration followed by a different separation of the ligands as a function of the chain-length and the position of the substituents of the ligands.