PREPARATION AND STUDY OF SOME COMPLEXES OF TRANSITION ELEMENTS WITH POLYDENTATE LIGANDS

Abstract: This research includes the preparation of ligands with large cyclic molecules and their interaction with chromium (III), manganese (II), iron (III), cobalt (II), nickel (II), and copper (II). These complexes were characterized using the techniques of elemental microanalysis, electrical molar conductivity, magnetic measurement, infrared spectra, and electronic spectra. From these measurements, it was found that the expected chemical composition of the complexes is [M(L)Cl₂], where M = (Mn, Co, Ni, Cu) and L = (L_2,3py, L_2,6py), and [M(L)Cl₂]Cl, where M = (Cr, Fe) and L = (L_2,3py, L_2,6py), and that all the complexes have an octahedral structure. The effect of the obtained ligands on the growth of bacteria, namely, strains of Staphylococcus aureus and Klebsiella pneumoniae, was studied. The results indicate that the cobalt (II), nickel (II), and copper (II) complexes of ligand L_2,3 have a greater effect on different types of bacteria compared to the composite of ligand L_2,6, which gave a lower rate of effectiveness.