METAL-COMPLEXES OF SOME AZO DYES DERIVED FROM 4-AMINOANTIPYRINE

Fe(III), Ni(II), Co(II), Cu(II) and UO2(VI) complexes of antipyrine-4- azo-beta-ethylcyanoacetate (HL1), antipyrine-4-azo-beta-acetylactone ( HL2) and antipyrine-4-azo-beta-ethylacetoacetate (HL3) have been prepa red and characterized by using analytical, spectral, magnetic and ther mal measurements. The analytical and i.r. spectral results show that t he ligands HL1 and HL2 behave as neutral bidentates in the hydrazone f orm when react with FeCl3, whereas the ligands behave as monobasic tri dentates in the azo form when react with NiCl2, CoCl2, CuCl2 and UO2(C H3COO)2. The analytical, spectral and magnetic data also reveal that t he Fe(III) complexes, Cu(II) complex with HL1 and Co(II) complex with HL2 are binuclear complexes involving chloride or enolic oxygen bridge s.