Synthesis, characterisation, antimicrobial studies and corrosion inhibition potential of 1,8-dimethyl-1,3,6,8,10,13- Hexaazacyclotetradecane

Abstract

The synthesis of 1 ,8-dimethyl- 1,3,6,8,10,1 3-hexaazacyclotetradecane ligand was carried out by the demetallation of the prepared 1,8-dimethyl-1,3,6,8,10,13.. hexaazacyclotetradecanenickel(Il) complex. The characterization of the ligand and the nickel (II) complex was carried out using the UV-Vis, FT-IR, EDX, MS, NMR and TGA techniques. The structure was confirmed by the methods used and the TGA showed the mode of thermal stability and decomposition. The ligand displayed three steps losses upon dynamic heating at 1200 °C. The biological activity of the ligand against two bacterial strains namely Staphylococcus aureus and Enterococcus species was also studied. The result shows the ligand to be potentially active towards the bacterial strains. The corrosion inhibition potential of the ligand was studied using Potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The PDP and EIS showed that the %IE increases as the concentration increased. The CV provided insight into the kinetics and the effect of scan rate on peak currents. The ligand was found to be a mixed-type inhibitor. The phenomenon of chemisorption mechanism was proposed from the thermodynamic parameters obtained. The experimental result fits the Langmuir adsorption isotherm.