Synthesis of new imidazole derivatives, characterization and determination of their protonation constants

Synthesis of New İmidazole Derivatives, Characterization and Determination of Their Protonation ConstantsIn the first stage of this work which was planned in two stages, two compounds containing imidazole ring were synthesized and characterized. In the characterization, instrumental techniques such as IR, 1H-NMR and 13C-NMR were used. In the second stage, protonation constants of the compounds were determined by potentiometric titration method in %70 dimethyl sulfoxide-%30 water media at 25 ± 0.1oC under nitrogen atmosphere and at constant ionic strength of 0.1 M. Obtained data from the titrations 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 potentiometric and analytical studies, it has been observed that the imidazoles ligands titrated which containing acetamide group here have two protonation constants. On the other hand, protonation constant of the substents dealing with hydrazone moiety have not been observed due to its less solubility.Key Words:İmidazole, Potentiometric Titrations, Protonation Constants