Molecular Features and Transport Properties of Dbu Based Protic Ionic Liquids

Abstract

High vapor pressure and flammability are some disadvantages of organic solvents currently used in chemical processes. In this scenario, protic ionic liquids (PILs) became a promising alternative to replace conventional solvents due to their interesting physicochemical properties. Understanding the charge transport and molecular features governing PILs is still required to allow their implementation in current and new technologies. Thus, the present work reports the study of PILs based on the 1,8-diazabicyclo-[5,4,0]-undec-7-ene (DBU) cation and two anions obtained from strong acids, trifluoromethylsulfonate (TFO-) and bis(trifluoromethylsulfonyl)imide (TFSI-) using different NMR techniques. 1H NMR spectra confirm that the high acidity of the PILs constituents is a determinant factor governing their features. Moreover, information on the transport properties of the PILs is obtained by diffusion NMR. The results show a peculiar behavior of the acidic proton, indicative of a different mechanism of charge transport in these systems.