Understanding the solvation process and solute-solvent interactions of imidazole compounds in three different solvents through solution calorimetry and 1H NMR

Abstract

The enthalpies of solvation of imidazole, 2-methyl-, 2-ethyl- and 2-isopropyl-imidazole in water, methanol and acetonitrile were determined through thermochemical measurements of the corresponding enthalpies of sublimation and solution. The Pierotti equation, which incorporates the enthalpy of cavity formation and the solvent reorganization for each solute in each solvent, was used to obtain the corresponding enthalpies of interaction. Additionally, the 1H NMR spectra of all solutes, in the corresponding deuterated solvents, were also obtained. The discussion of the solvation process and enthalpies of interaction of the imidazole compounds is based on the specific intermolecular interactions, like hydrogen bonds, H − π and non-specific interactions from London forces nature, supported by the features of the 1H NMR spectra of each solute in each solvent.