Application of Diffusion‐Ordered Spectroscopy (DOSY) as a Solvent Signal Filter for NMR in Neat Ionic Liquids

Abstract

The use of common, that is nondeuterated, ionic liquids for NMR spectroscopic purposes as the only solvent causes large signals arising from solvent resonances. Ionic liquids (ILs) with long side chains possess signals throughout the spectral range of protons, thus rendering simple solvent signal suppression techniques ineffective. Here we present solvent signal suppression based on diffusion-ordered NMR spectroscopy (DOSY). In contrast to the well established usage of

Magnetic resonance spectroscopy in ionic liquids

“…We could show, however, that at least the removal of solvent signals from the spectrum is possible by diffusion ordered spectroscopy (DOSY) and computational removal of the solvent signals (''DOSY-editing'') [117]. Unfortunately, this technique is limited to systems without overlap in the direct dimension and does not help to reduce the dynamic range.…”

Heteronuclear NOE Spectroscopy of Ionic Liquids

“…For the last eight years our group has focussed on the establishment and application of NMR spectroscopy in neat ILs. [4][5][6][7][8] It is long established that the nuclear Overhauser effect (NOE) [9] is a powerful tool for the determination of intermolecular interactions. [10][11][12] This effect arises due to dipolar cross relaxation between two spatially neighbouring nuclear spins (typically below 5 ).…”

PGSE NMR Diffusion Overhauser Studies on [Ru(Cp*)(η6‐arene)][PF6], Plus a Variety of Transition‐Metal, Inorganic, and Organic Salts: An Overview of Ion Pairing in Dichloromethane

“…[16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] Nevertheless, one finds an increasing number of reports involving NMR data and ion pairing. [15,17,[31][32][33] Assuming that the two ions can be measured separately, inspection of the magnitudes of the NMR diffusion constants provides a direct estimate of the extent of the Abstract: PGSE diffusion, 19 F, 1 H HOESY and 13 À salts of transitionmetal, inorganic, and organic salts are compared. Taken together, these new results show that the charge distribution and the ability of the anion to approach the positively charged positions (steric effects due to molecular shape)…”