Synthesis, Characterization , Thermal Studies and Antioxidant Activities of Transition Metal Complexes with Azo Dye ligand

Abstract

Diazotization reaction between 1-(2,4,6-Trihydroxy-phenyl)-ethanone and diazonium salts was carried out resulting in ligand 4-(3-Acetyl-2,4,6-trihydroxy-phenylazo)-N-(5-methyl-isoxazol-3-yl)-benzenesulfonamide, this in turn reacted with the next metal ions (V⁴⁺ , Cr³⁺ , Mn²⁺ and Cu²⁺) forming stable complexes with unique geometries such as (Octahedral for both Cr³⁺ , Mn²⁺ and Cu²⁺ ,squar pyramidal for V⁴⁺). The creation of such complexes was detected by employing spectroscopic means involving ultraviolet-visible which proved the obtained geometries, fourier transfer proved the formation of azo group and and the coordination with metal ion through it. Pyrolysis (TGA & DSC) studies proved the coordination of water residues with metal ions inside the coordination sphere as well as chlorine atoms. Moreover, element micro-analysis and AAS that gave corresponding outcome with theoretically counting outcome. (¹H &¹³C-NMR) and magnetic quantifications can also indicate the formation of ligand-H₃L and occurrence of coordination. The thermodynamic constants (∆H, ∆S and ∆G) were calculated. The DPPH radical scavenging method will be used to assess the antioxidant activities of the compounds the compounds showed antioxidant abilities to scavenge free radical.

Received 14/01/2023

Revised 31/03/2023

Accepted 02/04/2023

Published Online First 20/10/2023