New Water-Stable Ionic Liquids Based on Tetrakis-(2,2,2-trifluoroethoxy)borate

Several new ionic liquids (ILs) were prepared from Na[B(tfe)4] (tfe=OCH2CF3) via metathesis, including one room temperature IL (RTIL). Prior to synthesis, suitable cations were chosen via predictive quantum‐chemical calculations. Nuclear magnetic resonance monitoring over almost a month showed a total stability of the anion in the presence of water. The temperature‐dependent viscosities and melting points of all the new ILs were determined. The data indicate that [B(tfe)4]− ILs may be too viscous for electrochemical applications, but are interesting candidates for lubricant research. No chance for hydrolysis: A new class of ionic liquids containing the [B(tfe)4]− anion (tfe=OCH2CF3) is synthesized and characterized. Key features of these compounds include complete stability in the presence of water as well as viscosity data indicating that they could be promising candidates for lubricant research.