Structural features of selected protic ionic liquids based on a super-strong base.

Protic Ionic Liquids (PIL) prepared from super-strong base 1,7-diazabicyclo[5.4.0]undec-7-ene (DBU) and super-strong acids, trifluoromethane sulfonic acid (TfOH) and (trifluoromethanesulfonyl)-(nonafluorobutylsulfonyl)imide, (IM14H), have been prepared ([DBUH][TfO] and [DBUH][IM14], respectively; the latter for the first time) and their chemical physical properties and structural features been explored using a synergy of experimental and computational tools. The short range order in neat DBU, as well as the long range structural correlations induced by charge correlation and hydrogen bonding interactions in the ionic liquids, have been explored at ambient conditions, where these compounds are proposed for a variety of applications. Similarly to other [DBUH]-based PILs, the probed ones behave as good ionic liquids. Molecular Dynamics-rationalised X-ray diffraction patterns show the major role played by hydrogen bonding in affecting morphology in these systems. Additionally we find further evidence of the existence of fluorous domains in [DBUH][IM14], thus potentially extending the range of applications for these PILs.