The effect of anion fluorination in ionic liquids—physical properties of a range of bis(methanesulfonyl)amide salts

Abstract

The bis(trifluoromethanesulfonyl)amide, TFSA, anion is widely used in the genesis of room temperature ionic liquids as it is non-spherical, fluorinated and has a particularly diffuse charge. However, the extent to which each of these structural features is responsible for the low melting point, fluidity and excellent stability of the resultant ionic liquids has yet to be described. We present the synthesis and analysis of a range of analogous, non-fluorinated species containing the bis(methanesulfonyl)amide, NMes 2 À , ligand. Utilisation of this anion produces ionic liquids that are hydrophilic and extremely low melting, but with decreased thermal and electrical stability and significantly increased viscosity. The crystal structures of the dimethyl pyrrolidinium bis(methanesulfonyl)amide and TFSA species are compared, and the number of close contacts within each is assessed. Comparison of these structural and physical properties provides new insight into the effect of anion fluorination on these ionic liquids.

Ionic Liquids for the Synthesis and Stabilization of Metal Nanoparticles

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Stabilization of native penicillin G acylase by ionic liquids

“…8 In this sense, ILs could be an alternative to organic solvents, because of their lack of vapour pressure, their chemical and thermal stability 9 and their widely tunable properties with regard to polarity, hydrophobicity and solvent miscibility behavior through appropiate modification of the cation and anion. 10,11 They are therefore often referred to as designer solvents. The most commonly used ILs are based on dialkylimidazolium and tetraalkyl ammonium cations combined with anions having a strongly delocalized negative charge (e.g.…”

Imidazolium-Based Ionic Liquid Binary Solvent System as an Extraction Medium in Enhancing the Rotenone Yield Extracted from Derris elliptica Roots

“…The density (ρ) of ionic liquids (ILs) decreases with the increase in organic cation bulkiness and anion selection affects ILs' density. Normally, the density of ILs varies in the range of 1.05-1.36 g/cm 3 at ambient temperature [43,44]. In terms of ILs' thermal stability, a research conducted had observed that thermal stability was dependent on both the cation and the anion of ILs.…”