‘Unusual Anions’ as Ionic Liquid Constituents

Synthesis, Characterization, and Physicochemical Properties of New [Emim][BF3X] Complex Anion Ionic Liquids

“…However, the preparation of these modified anions involves highly hazardous processes (F 2 fluorination, electrochemical fluorination), , with expensive reagents (AlkLi, perfluorinated hydrocarbons). , These factors make ILs based on these modified anions expensive and restrict the further development of these ILs. Until now, these ILs are still classified as “unusual anion-based ILs”, although they were synthesized 20 years ago …”

“…Until now, these ILs are still classified as "unusual anion-based ILs", although they were synthesized 20 years ago. 20 Herein, a new effective strategy by designing anions for "Task-specific" ILs was first proposed via hybrid complexing Lewis fluoroacids MF n with common ILs (Q + X − ) to obtain complex anion ILs (Q + [MF n X] − ). 21 This strategy significantly modifies the structural properties of the anion [X] − , including symmetry, donor ability, and conformational degrees of freedom, and allows one to control the strength of the Coulomb interactions, hydrogen bonding, dispersion, and dipole−dipole interactions in the ILs, 22 thus obtaining ILs with specific physicochemical properties.…”