SYNTHESIS, CHEMICAL CHARACTERIZATION AND THERMAL-BEHAVIOR OF 1,2-DITHIOOXALATO-S,S' COMPLEXES OF NI(II), PD(II) AND PT(II) WITH 2-AMINO-3-METHYLPYRIDINIUM

Three compounds of formula (HB)2[M(dto)2], where HB+ is 2-amino-3-meth ylpyridinium, dto2- is 1,2-dithiooxalato-S,S' ligand, and M is Ni(II), Pd(II), or Pt(II), have been synthesized and characterized by element al analysis, and infrared and UV-Vis spectroscopy. The thermal behavio ur of these complexes was studied by thermogravimetry (TG) and differe ntial thermal analysis (DTA) under argon and argon-oxygen atmospheres. The final products of the thermal decomposition were examined by elem ental analysis and X-ray powder diffractometry. The IR and UV-Vis spec tra indicate the presence of the aromatic cations and the complex anio ns. The thermal analytical data show that the starting compounds and t he surrounding atmosphere significantly influence the course of the de composition reactions, as well as the final products. In an oxidative atmosphere, a mixture of nickel(II, III) oxides and sulphides, palladi um(II) oxide and metallic platinum were obtained, whereas in an inert atmosphere, nickel sulphides, palladium(II) sulphide and platinum(0) w ere identified as the final products.