The power of novel morpholinyl Mannich bases to protect N80 steel against corrosion in acidic environment: DFT and SAR investigations

Abstract

In this research article, we investigate the corrosion inhibition properties of two novel morpholinyl mannich bases namely 3-morpholino-1-phenylpropan-1-one (MB1) and 3-morpholino-1-phenyl-3-(pyridin-4-yl) propan-1-one (MB2). To establish a link between their corrosion inhibition efficacy and molecular characteristics, we employ a comprehensive approach involving the calculation of DFT-derived global and local reactivity parameters, as well as structure-activity relationship (SAR) indices. The obtained values of the global reactivity indices including dipole moment, energy gap, hardness, and softness show a positive correlation with the experimental data earlier reported. Fukui functions give a comprehensive reactive scheme exhibiting the atoms responsible for the electronic transfer. SAR parameters such as molecular volume (V), surface area (SA), and the polarizability (α) were found to be in good accordance with the experimental inhibition effectiveness order.