Air stable liquid clathrates: Solid state structure and hydrocarbon solubility of organic cation triiodide salts

Christie, Sean; Dubois, Raymond H.; Rogers, Robin D.; White, Peter S.; Zaworotko, Michael J.

doi:10.1007/bf01153294

Cited by 17 publications

(7 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Structures containing the same pyridinium cation were not found in the CSD . However, structures with similar pyridinium cations have been reported, containing short alkyl chains of one carbon atom and a COOH, CH 3 , COH, CONH 2 or CSeH groups. − In these structures, interactions have also been observed between the C–H pyridinium ring atoms and the respective anions, together with additional interactions between the functionalizing groups and the respective anions.…”

Section: Resultsmentioning

confidence: 77%

Nitrile-Functionalized Pyridinium, Pyrrolidinium, and Piperidinium Ionic Liquids

et al. 2011

View full text Add to dashboard Cite

Two series of 1-alkylpyridinium and N-alkyl-N-methylpiperidinium ionic liquids functionalized with a nitrile group at the end of the alkyl chain have been synthesized. Structural modifications include a change of the alkyl spacer length between the nitrile group and the heterocycle of the cationic core, as well as adding methyl or ethyl substituents on different positions of the pyridinium ring. The anions are the bromide and the bis(trifluoromethylsulfonyl)imide ion. All the bis(trifluoromethylsulfonyl)imide salts as well as the bromide salts with a long alkyl spacer were obtained as viscous liquids at room temperature, but some turned out to be supercooled liquids. In addition, pyrrolidinium and piperidinium ionic liquids with two nitrile functions attached to the heterocyclic core have been prepared. The crystal structures of seven pyridinium bis(trifluoromethylsulfonyl)imide salts are reported. Quantum chemical calculations have been performed on model cations and ion pairs with the bis(trifluoromethylsulfonyl)imide anion. A continuum model has been used to take solvation effects into account. These calculations show that the natural partial charge on the nitrogen atom of the nitrile group becomes more negative when the length of the alkyl spacer between the nitrile functional group and the heterocyclic core of the cation is increased. Methyl or methoxy substituents on the pyridinium ring slightly increase the negative charge on the nitrile nitrogen atom due to their electron-donating abilities. The position of the substituent (ortho, meta, or para) has only a very minor effect on the charge of the nitrogen atom. The (15)N NMR spectra of the bis(trifluoromethylsulfonyl)imide ionic liquids were recorded with the nitrogen-15 nucleus at its natural abundance. The chemical shift of the (15)N nucleus of the nitrile nitrogen atom could be correlated with the calculated negative partial charge on the nitrogen atom.

show abstract

Section: Resultsmentioning

confidence: 77%

Nitrile-Functionalized Pyridinium, Pyrrolidinium, and Piperidinium Ionic Liquids

et al. 2011

View full text Add to dashboard Cite

show abstract

“…The Δδ H,cation values obtained by 1 H NMR spectroscopy (Figure 12) reveal that the toluene-cation interactions have a similar strength to water-cation ones in the [C 2 mim][SCN] IL, but they are stronger in the [C 2 mim][DCA] IL and much stronger in the [C 2 mim][TCM] IL as the chemical shifts are more upfield located. Related to Δδ C,anion values obtained by 13 C NMR spectroscopy (Figure 13 Overall, these results indicate that an increase in the number of À CN groups in the anion leads to a lower water affinity (lower basicity) and a higher toluene affinity (because of the weaker cation-anion interactions), and thus, a larger aromatic hydrocarbon content in the LC.…”

Section: Water Interaction With Ilsmentioning

confidence: 85%

“…Atwood et al first described LCs as a group of nonstoichiometric compounds formed upon the interaction of aromatic molecules and certain alkylaluminum salts, characterized by having anions with angular geometry, dipole moment, and a negative charge localized on an accessible end. [11] This first study, and the knowledge that aromatic compounds are soluble in but rarely completely miscible with ILs, [12] led to a deeper investigation on LC systems [3,[13][14][15][16] till Holbrey et al established that LCs were spontaneously formed when ILs were mixed with an excess of aromatic hydrocarbons. [4] The ionic nature of the ILs and the aromaticity of the solutes are responsible for LC formation, but more complex interactions are present in these systems as well.…”

Section: Introductionmentioning

confidence: 99%

Insights into Ionic Liquid/Aromatic Systems from NMR Spectroscopy: How Water Affects Solubility and Intermolecular Interactions

et al. 2019

Self Cite

View full text Add to dashboard Cite

Hydrocarbon solubility and chemical interactions in ten imidazolium‐ and pyridinium‐based ionic liquids (ILs) with four different anions (thiocyanate [SCN]−, dicyanamide [DCA]−, tricyanomethanide [TCM]−, and bis(trifuoromethylsulfonyl)imide [NTf2]−) have been studied by 1H and 13C NMR spectroscopy. The anion structure has the main influence on the anion–aromatic chemical interaction strength; it is directly correlated to the NMR chemical shift deviations but not to the hydrocarbon solubility. The [TCM]− anion shows the largest chemical shift deviations, but the [NTf2]− anion has the highest hydrocarbon solubility due to steric effects. Higher water contents decrease the hydrocarbon solubility in ILs. Ion‐water solvation mainly occurs until 1 molwater/molIL with the saturation limit at 10 molwater/molIL. Toluene‐ion interactions are stronger than water–ion interactions in [DCA]− and [TCM]−‐based ILs, but they have a similar or even lower strength in [SCN]−‐based ILs.

show abstract

“…. These parallel chains form layers separated by 2-chloro-N-methylpyridinium cations exhibiting bonds and angles similar to those in the salts Nmethylpyridinium iodide (Lalancette et al, 1978) and Nethylpyridinium triiodide (Christie et al, 1991). The chlorine substituent in (I) shows an additional weak coordination to the triiodide anion with distances Cl2Á Á ÁI1 = 3.889 (2) and Cl2Á Á ÁI2 = 3.637 (2) A Ê .…”

Section: Commentmentioning

confidence: 89%

Bis(2-chloro-N-methylpyridinium) iodide triiodide

2000

View full text Add to dashboard Cite

show abstract

Air stable liquid clathrates: Solid state structure and hydrocarbon solubility of organic cation triiodide salts

Cited by 17 publications

References 21 publications

Nitrile-Functionalized Pyridinium, Pyrrolidinium, and Piperidinium Ionic Liquids

Nitrile-Functionalized Pyridinium, Pyrrolidinium, and Piperidinium Ionic Liquids

Insights into Ionic Liquid/Aromatic Systems from NMR Spectroscopy: How Water Affects Solubility and Intermolecular Interactions

Bis(2-chloro-N-methylpyridinium) iodide triiodide

Contact Info

Product

Resources

About