Complexing behaviour of naphthylidene sulfamethazine schiff base ligand towards some metal ions

Mn [II], Co [II], Ni [II] and Cu [II] complexes of the Schiff base derived from 2-hydroxy-1-naphthaldehyde and sulfamethazine were prepared by both chemical and electrochemical methods. The structure of the complexes was investigated by chemical microanalysis, conductance and magnetic moment measurements as well as spectral methods. The results indicated that the Schiff base ligand behaved as tetradentate dibasic for 1:2 [L:M] complexes and bidentate monobasic for 1:1 and 2:1 [L:M] complexes. The thermal behavior of the complexes was studied using TGA and DTA. The energy of activation [Ea] for the decomposition process was calculated. The values of Ea of binuclear complexes were higher than those of the mononuclear complexes. For the 1:1 complexes, Ea increased as the ionic radii of metal ion increased

electrochemical formation of nitrosonaphthol complexes I. Spectral, magnetic and thermal studies of Fe [II], Co [II], Ni [II], Cu [II] and Cd [II] complexes

Electrochemical and chemical reaction of alpha-nitroso-beta-naphthol [HL] with some transition metals gave complexes of the type ML2nH2O and MLCl[H2O]nH2O. The mixed ligand adduct [CuL2L]2H2O was also prepared, where L=1,10-phenanthroline. The complexes have been characterized by elemental analyses and differential thermal analysis [DTA]. The thermal stability of the investigated complexes is discussed in terms of the type of metal ions and structure of the complexes. The energy of activation of the thermal decomposition is determined. The bonding of the complexes is confirmed IR spectra while, the electronic and ESR-spectra as well as magnetic measurements indicated the arrangement of the ligand groups around the central metal ions