Synthesis and properties of protic hydroxylic ionic liquids with two types of basic centers in their composition

1-((3-(1H-imidazol-1-yl)propyl)amino)-3-butoxypropan-2-ol with two types of nitrogenous centers and variable basicity was synthesized by reaction of butyl glycidyl ether with 1-(3-aminopropyl)imidazole. Ethanesulfonic acid was used for equimolar and complete neutralization of the obtained compound to produce hydroxylic ionic liquids. N-acetyl derivatives of the given liquid with ethanesulfonate and acetate counterions were also synthesized. According to 1H NMR spectroscopy, equimolarly neutralized compounds are characterized by a rapid migration of protons between the basic centers using the mechanisms of intermolecular and intramolecular transfer with a predominance of the latter at higher temperatures. Fully protonated ionic liquids are characterized by a low glass transition temperature (− 60.9 °С) and a high conductivity 5.45·10− 4 S/cm at 20 °C under anhydrous conditions. Notably, there is an absence of determined correlation between the glass transition temperature or conductivity and the value of the viscosity of the ILs.