INTERACTIONS OF SQUARIC AND CROCONIC ACIDS WITH [PTL4](2+) COMPLEXES (L = NH3, L2 = ETHYLENEDIAMINE) - OXIDATIVE PROPERTIES OF OXOCARBON ACIDS AND CRYSTAL-STRUCTURE DETERMINATIONS

Squaric (H2Sq) and croconic (H2Croc) acid (H2A) react with [PtL4]2+ (L = ammonia or L2 = ethylenediamine) to yield complexes formulating as [PtL4](HA)2. The crystal structure of the complexes [Pt(en)2](HSq)2 and [Pt(en)2](HCroc)2 have been determined using X-ray diffraction techniques. Oxidation of platinum occurred in the course of the same reaction and complexes of [PtL4Cl2]A were obtained. The X-ray determination of the structure of [Pt(NH3)4Cl2]Sq is reported. Electrochemical measurements have been performed in the solid state to support the results obtained during the oxidation process.