Determination of the pKa value of some 1,2,4-triazol derivatives in forty seven different solvents using semi-empirical quantum methods (PM7, PM6, PM6-DH2, RM1, PM3, AM1, and MNDO) by MOPAC computer program

Abstract In this study, we calculated the enthalpy (Δ H , kcal/mol), entropy (∆ S cal/K·mol) and free energy G kcal/mol) thermodynamic values of each molecule for forty-seven different solvent media according to semi-empirical quantum methods (PM7, PM6, PM6-DH2, RM1, PM3, AM1, MNDO) using MOPAC computer program. The theoretical pKa were by placing these in cycle. It was determined that triazole derivative molecules examined study showed a very high acidity trifluoroacetic acid low cyclohexane. fifth (pKa :1.2457) RM1 method. On other hand, it fourth : 69.5668) cyclohexane