Synthesis, Characterization, Antioxidant, and Theoretical Studies of the Schiff Base Derivative of (4H-1,2,4-Triazole-3,5-Diamine) and Its Complexes With Co(II) & Cu(II) Ions

Schiff bases are widely studied for their potential biological activities, particularly as antioxidants. This study synthesized a Schiff base derivative from (4H-1,2,4-triazole-3,5-diamine) through condensation with o-vanillin and investigated its metal complexes with Co (II) and Cu (II) ions. Despite the known antioxidant properties of Schiff bases, there is limited information on their metal complexes' antioxidant and structural behaviors. The aim was to synthesize, characterize, and assess the antioxidant activity of the ligand and its metal complexes. The compounds were characterized using elemental analysis, FTIR, 1H-NMR, mass spectrometry, magnetic susceptibility, and molar conductivity. DFT calculations using B3LYP/6-31+G(d,p) were performed for geometry optimization and energy gap analysis. The ligand exhibited significant antioxidant activity, while Co (II) complexes adopted a tetrahedral geometry and Cu (II) complexes a square planar geometry. These findings highlight the Schiff base's potential in antioxidant applications and contribute to understanding metal-ligand interactions.