Research on three complex compounds of divalent first-row transition metal ions having the Schiff base derived from sulfanilamide and N-acetylisatin as bidentate ligand

Abstract

The present paper aims to describe the research performed on three complex compounds formed by divalent first-row transition metal ions – namely M = Co(II), Ni(II) and Zn(II) (representing the complex kernels) with the Schiff base derived from the condensation of sulfanilamide with N-acetylisatin (which proved itself to be able to act as a bidentate ligand in all these cases). This Schiff base is N-(1-acetyl-2-oxoindolin-3-ylidene)-4-aminobenzenesulfonamide, which appears twice in each complex, but is not the only ligand in the structure, as two water molecules are also part of the coordination sphere; there also is an ionization sphere, represented by two chloride ions whose role is to equilibrate the electrical charge of the complex kernel (all the ligands being charge-free) – the general molecular formula of the complexes being thus: [ML2(H2O)2]Cl2. From the electrical point of view, we dealt with three complex compounds that all showed themselves to be electrolytes. As far as magnetic properties are concerned, two of them proved themselves to be paramagnetic, whereas the last one was found to be diamagnetic. After adding different spectral data, corroborating them with the prior information and with the elemental analysis – we have drawn the conclusion that the complexes are six-coordinated, so they all will tend to adopt an octahedral geometry.