Electrochemical and theoretical studies on the corrosion inhibition performance of some synthesized d-Limonene based heterocyclic compounds

The present work focuses on the synthesis, structural characterization and electrochemical investigation of some heterocyclic compounds prepared from d -limonene. Firstly, 3-acetylisoxazoline was synthesized from d -limonene, this precursor is then converted to its thiosemicarbazone derivatives which were then cyclized to produce their corresponding thiazolidine-4-ones. The obtained compounds were characterized by FT-IR, 1H NMR, 13C NMR and mass spectrometric techniques. Further, DFT quantum chemical studies were also used to interpret the structural properties of the compounds using the B3LYP/6–311++G (d, p) basis set. The obtained results from experimental and theoretical studies were in good agreement showing that compounds bearing both isoxazoline and thiazolidine-4-one moieties act as good corrosion inhibitors for stainless steel in 1 M sulfuric acid.