Spectroscopic characterization, thermogravimetric and antimicrobial studies of some new metal complexes derived from4‐(4‐Isopropyl phenyl)‐2‐oxo‐6‐phenyl 1,2‐dihyropyridine‐3‐carbonitrile (L)

Abstract

A new series of Fe (III), Co (II), Zn (II), Y (III), Zr (IV) and La (III) complexes derived from the novel ligand 4‐(4‐Isopropyl phenyl)‐2‐oxo‐6‐phenyl 1,2‐dihyropyridine‐3‐carbonitrile (L) were synthesized and characterized. The mode of bonding of L and geometrical structures of their metal complexes were elucidated by different micro analytical and spectral methods (FT‐IR,UV–visible,1H NMR and Mass spectra) as well as thermal analysis (TG and DTG), and differential scanning calorimetry (DSC). The results of analytical and spectroscopic equipments revealed that L acts as bidentate through nitrogen of carbonitrile group and oxygen of keto group. The conductivity measurement results deduced that these chelates are electrolyte with 1:2 for Co (II), Zn (II), and Zr (IV) and 1:3 for Fe (III), Y (III), and La (III). The results of magnetic moment measurements supported paramagnetic for some complexes (Fe (III), Co (II) and Cu (II)) and diamagnetic phenomena for the other complexes (Y (III), Zr (IV) and La (III)). Thermodynamic parameters such as energy of activation E*, entropy ΔS*, enthalpy ΔH* and Gibss free energy ΔG* were calculated using Coats‐Redfern and Horowitz‐Metzeger methods at n = 1 or n#1. Some results of bioactivity tests for ligands and their metal complexes were recorded against Gram‐positive, Gram‐negative bacteria and antifungal. The complexes showed significant more than free ligand.