Synthesis, characterization and anti-corrosion study of Ni(II) and Cu(II) complexes with Schiff base based on 3,5-dichlorosalicylaldehyde and 2-aminobenzenethiol

Schiff base ligand derived from 3,5-dichlorosalsyldehyde and 2-aminobenzethiol was synthesized by mixing the two compounds in a condensation reaction in 1:1 molar ratio. Nickel(II) and copper(II) complexes of this ligand were also synthesized by refluxing the ligand with both mentioned metal chloride salts. The synthesized compounds were characterized by the available characterization methods such as 1HMNR, 13CNMR, mass spectroscopy, FTIR, UV-Vis and molar conductivity. Based on these characterization methods, the proposed structures of both complexes adopt an octahedral geometry, where the ligand coordinates through the azomethine, hydroxyl, and thione functional groups. The anti-corrosion activities of the synthesized compounds were investigated under two temperatures (298 K and 308 K) and two concentrations (0.01 and 0.05M). The Cu(II) complex exhibited superior anti-corrosion activity (94%) compared to the free ligand and the Ni(II) complex. KEY WORDS: 3,5-Dichlorosalicylaldehyde, 2-Aminobenzenethiol, Schiff base, Cu(II) and Ni(II) complexes, Anticorrosion activity Bull. Chem. Soc. Ethiop. 2025, 39(10), 1937-1948. DOI: https://dx.doi.org/10.4314/bcse.v39i10.5