Synthesis, Identification of Co(II), Cu(II) and Ni(II) Complexes with A Schiff Base–Azo Ligand Derived from Imidazol Derivatives, 4- Aminoacetophenon and 4- Chloroaniline and Study Their Physical Properties and Their Thermodynamic Stabilities

Aesa Farhan

doi:10.29196/jubpas.v27i3.2554

Abstract

The complexes of Co(II), Cu(II) and Ni(II) were synthesized by using schiff base – azo as a ligand, which were prepared under this study by the reaction between the Schiff base diazonium salt and the imidazole derevitive. They were characterized by element analysis, FTIR spectroscopy and UV.VIS. spectroscopy. Their electric conductivity and magnetic features were determined. Their stepwise and overall stability constants and their thermodynamic data ( , and ) were determined. The results showed that all the complexes have paramagnetic features and all of them have good conductivity. The formula of the complexes under this paper were suggested by using the mole ratio method which lead to the formation of (1 : 2) metal : ligand formula for all the complexes. In all the complexes the coordinated sites was through N atoms of the azo groups and N atom of the imidazol ring. The suggested geometrical shapes of the complexes was the octahedral shape due to the ( d2sp3 ) hybridization. Their stepwise stability constants were determined, it was found that for all the complexes they were increased toward the addition of ligand that because of the chelate effect. Their overall stability constants were determined, it was found that for all the complexes were high that because of the chelate effect. Their thermodynamic functions ( , and ) were had negative value, that refer to good stability for the complexes and these results were satisfied with the spontaneous reaction and high stability complexes.

Highlights

In 1885 Peter Griess had been showed that the aromatic amines rapidly react with nitrose acid under cooling to give easy – water solubility salts, which called diazonium salts[1], these salts have electrophilic properties so it can coupling with the high electronic density compounds such as the aromatic compounds with - NH2, NR2, - OH, - OR, groups to obtain the azo compounds[2]
There are two types of aromatic azo compounds, the first one is homogeneous azo compounds which composed of two homogeneous aromatic rings laying at the two sides of the azo group, the second type is non – homogeneous azo compounds which contain a non – homogeneous aromatic ring on one of sides of the azo group[4].Our ligand under this study belongs to the second type, the compounds of this type are more uses and important than the first one because it has active atom ( N, O, S ) which shares
The high molecular weight of a coordination complexes have a wide importance in field of clinical and analytical chemistry in recent days that because of their high stability and their wide use[6,7,8]

Summary

Introduction

In 1885 Peter Griess had been showed that the aromatic amines rapidly react with nitrose acid under cooling to give easy – water solubility salts, which called diazonium salts[1], these salts have electrophilic properties so it can coupling with the high electronic density compounds such as the aromatic compounds with - NH2 , NR2 , - OH , - OR , groups to obtain the azo compounds[2]. 2 – preparation of azo – Schiff base ligand:2.445 gm ( 0.01 mol ) of Schiff base was dissolved in 20 ml of 5 M HCl at 0O C, 0.07 gm ( 0.01 mol ) of sodium nitrite was dissolved in 10 ml of distilled water and added slowly by stirring at this temperature for 15 minute to obtain the diazonium salt.

Results

Conclusion