No abstract

A quantum chemical study of the efficiency of some o-, m-, and p-substituted benzohydrazides, cinnamohydrazide, and Schiff bases derived from salcylaldehyde with o-substituted anilines, psubstituted benzaldehydes with 2-aminopyridine and 2-aminopyrimidine, benzaldehyde and cinnamaldehyde with p-phenylenediamine as corrosion inhibitors of steel in the presence of 1M HCl is presented. The AM1, PM3, MINDO/3 and MNDO semi-empirical SCF molecular orbital methods were used. A possible correlation between corrosion inhibition efficiencies and structural properties was searched to reduce the number of compounds to be selected for testing from a library of compounds. Quantum parameters, total negative charge (TNC) on the molecule, energy of highest occupied molecular orbital (E HOMO ), energy of lowest unoccupied molecular orbital (E LUMO ), dipole moment (µ), total energy (TE), and linear solvation energy terms, molecular volume (Vi) and dipolar-polarization (π*) were correlated to corrosion inhibition efficiency of the studied compounds. The results were used to predict the corrosion inhibition of some related aromatic hydrazide derivatives with correlation coefficient r > 0.96.

Die Aroylazide (Ia) reagieren mit den Säurehydraziden (II) zu den Semicarbazid‐Derivaten (III); aus dem Phthalylazid (IV) wird das Benzimidazolon (V) erhalten.