Development of QSAR based GFA predictive model for the effective design of a new bispyrazole derivative corrosion inhibitor

Abstract

In this study, seven newly synthesized bispyrazole derivatives (PYR-1 to PYR-7) were investigated as corrosion inhibitors for 304 stainless steel (304 SS) in 1.0 M HCl solutions at different concentrations (10−13 to 10−5 M) using electrochemical frequency modulation technique (EFM). The experimental data were utilized to develop a predictive model for the anticorrosion abilities of bispyrazole ˗ based compounds. The model was developed by using the quantitative structure-activity relationship (QSAR) as a tool to relate essential molecular descriptors of bispyrazol with their experimental inhibition efficiencies. Chemical descriptors associated with frontier molecular orbitals (FMOs) were obtained using density Functional theory (DFT) calculations, while others were obtained from additional calculations performed using Material Studio 7 software. The suggested QSAR model was used to predict the corrosion inhibition efficiency of a newly synthesized bis[3‐(4`‐biphenyl)‐4‐[(4‐acetyl‐2‐(N‐phenylacetamido)‐4,5‐dihydro‐1,3,4‐thiadiazol‐5‐yl]‐1H‐pyrazol‐1‐yl]phosphineoxide,(PYR-8), another inhibitor within the same bispyrazole family. The predicted inhibition efficiency was validated by several electrochemical techniques. The predicted QSAR values for PYR-8 showed good agreement with experimental data, establishing the reliability of the model in predicting the inhibitor's performance.