CHARACTERIZATION AND ELECTROCHEMICAL PROPERTIES OF PYRINE-4-AZO-2-(5,5-DIMETHYL-1,3-CYCLOHEXANEDIONE) COMPLEXES OF PALLADIUM(II), IRON(III)AND RUTHENIUM(III)

Palladium(II), iron(III) and ruthenium(III) chloride complexes of anti pyrine-4-azo-2(5,5-dimethyl-1 ,3-cyclohexanedione) (HL) were prepared and characterized using analytical, spectral and magnetic measurements . The analytical and spectral data show that the reactions of K2PdCl4 (1 mol) in distilled water, FeCl3 . 6H(2)O and RuCl3 . 3H(2)O (1 mol) in ethanol with HL (1 mol) in ethanol produce 1:1 metal complexes. The studies reveal also that the ligand behaves as a neutral bidentate in its hydrate form when reacting with palladium(II) and as a monobasic tridentate in its azo form when reacting with trivalent iron and ruthe nium. The magnetic susceptibility shows that the palladium complex is diamagnetic, iron(III) is consistent with a high spin d(5) configurati on and ruthenium(III) is a low spin d(5). Cyclic voltammetry of tile c omplexes in acetonitrile at a platinum electrode has been performed. T he iron and ruthenium complexes show quasi reversible waves correspond ing to Fe-III/Fe-IV and Ru-III/Ru-IV redox processes respectively.