Synthesis Characterization and Biological Aspects of Fe III Co II Ni II and Zn II Complexes with some Nitrogen Donor Ligands

Abstract

The study of co-ordination compounds has emerged as one of the major center of attraction for the inorganic chemists. It covers a comprehensive range of fascinating and theoretical applications. In synthetic work they continue to provide a challenge in the laboratory. Coordination chemistry deals with intraction and stereochemical aspects between metals and different kinds of ligands. In coordination complexes metal ions are surrounded by donor atoms such as nitrogen, oxygen or sulphur in the lewis bases known as ligands. newlineMajority of the coordination compounds are those of transition elements. Among the transition elements the main transition group or d- block includes the elements that have partly filled d-orbitals either in the ground state of the free atom or in one or more of their chemically important ions. The d-orbital s project well out to the periphery of the atoms and ions so that the electrons occupying them are strongly influenced by the surroundings of the ions, and in turn are able to influence the environments very significantly. The coordination chemistry of transition metal complexes of chelating agents with sulphur-nitrogen donor sites has been an area of great interest for a number of years. The ligand system having soft sulphur and hard nitrogen atoms are chemically very versatile. In many of such complexes both nitrogen and sulphur atoms are involved in the bond formation to the metal while in some others the bond formation is either through nitrogen or through sulphur. The coordination geometry of these complexes depends upon the electronic configuration and size of the metal ions, repulsion between non-bonded atoms in different ligand arms, and the inherent rigidity due to the presence of aromatic rings, etc. newlineFor the last few decades, the coordination chemistry has gained significantly raised much importance among the various field of chemistry due to they are used as models in biological systems. Recently, Schiff base ligands and their transition metal complexes play a crucial role in br