Synthesis, characterization and determination of protonation constants by potentiometric titration method of new 3-mercapto-1,2,4-triazole derivatives

In the first stage of this work which was planned in two stages, four compounds containing 3-mercapto-1,2,4-triazole were synthesized and characterized. In the characterization, instrumental techniques such as IR, 1H NMR, 13C NMR and DSC were used. In the second stage, protonation constants at compounds which were synthesized here were determined by potentiometric titration method in %60 dioxane-%40 water media at 25 ± 0.1 ºC under nitrogen atmosphere and at a constant ionic strength of 0.1 M. Obtained data were evaluated by a computer programme, BEST. After that, by using potentiometric titrations values, the distribution diagrams which are indicating the changes of concentrations of the emerging species were plotted as a function of pH by using computer program SPEXY-C.As a result of the study, it has been observed that K1, K2 and K4 compounds have two different protonation constants, but K3 compound has three different protonation constants.