Synthesis of Gem-Dichlorocyclopropane Allylcarveol and Their Effect in Protecting Against Corrosion of Mild Steel in 1.0 M HCl

In this work, the gem-dichlorocyclopropane allylcarveols Carb_8-Carb_10 namely: 1-allyl-5-(2,2-dichloro-1-methylcyclopropyl-2-methylcyclohex-2-en-1-ol, 1-(but-3-en-2-yl)-5-(2,2-dichloro-1-methylcyclopropyl)-2-methylcyclohex-2-en-1-ol and 5-(2,2dichloro-1-methyl cyclopropyl)-1-((2,2-dichloro-1-methylcyclopropyl)methyl)-2 methylcyclohex-2-en-1-ol were synthesized from R-(-)-Carvone (the major constituent of spearmint oil) derivatives. In this synthesis, we used the technique of liquid-liquid phase transfer catalysis. These compounds were evaluated as corrosion inhibitors of steel in 1 M HCl by gravimetric methods. The acquired results prove that the inhibitory efficiency increases with concentration. The temperature effect on the corrosion behavior of steel in 1 M HCl in the presence and absence of inhibitors at 1×10-2 mol/l was studied in the temperature range of 313–343 K, the activation parameters of the corrosion reaction were calculated using the Arrhenius equation, and the transition state equation. The adsorption of this compound on Mild Steel surface obeys Freundlich’s adsorption isotherm. In the theoretical computations, we used the Density Functional Theory (DFT) and Monte Carlo simulations to find the best spatial configuration of inhibitors on the steel surface.