Vaporisation and thermal decomposition of dialkylimidazolium halide ion ionic liquids was written by Lovelock, Kevin R. J.;Armstrong, James P.;Licence, Peter;Jones, Robert G.. And the article was included in Physical Chemistry Chemical Physics in 2014.Quality Control of 1-Octyl-1H-imidazole This article mentions the following:
Vaporisation and liquid phase thermal decomposition, TD, of two halide ion ionic liquids, 1-octyl-3-methylimidazolium chloride, [C8C1Im]Cl, and 1-octyl-3-methylimidazolium iodide, [C8C1Im]I, are investigated using temperature programmed desorption (TPD) line of sight mass spectrometry (LOSMS) at ultra-high vacuum (UHV). The ability to use MS to distinguish between vaporization and TD allows the thermodn./kinetics of both vaporization and TD to be investigated within the same experiments Vaporisation of both halide ion ionic liquids is demonstrated. For both [C8C1Im]Cl and [C8C1Im]I the vapor is shown to be composed of neutral ion pairs (NIPs). The enthalpy of vaporization at temperature T, ΔvapHT, was exptl. determined as ΔvapH455 = 151 ± 10 kJ mol-1 for [C8C1Im]Cl and ΔvapH480 = 149 ± 8 kJ mol-1 for [C8C1Im]I. Extrapolation of ΔvapHT to the reference temperature, 298 K, gave ΔvapH298 = 166 ± 10 kJ mol-1 for [C8C1Im]Cl and ΔvapH298 = 167 ± 8 kJ mol-1 for [C8C1Im]I, higher than most ΔvapH298 values measured to date for other [C8C1Im]+-containing ionic liquids In addition, predictions of ΔvapH298 for other halide ion ionic liquids are made. Liquid phase TD is shown to proceed via nucleophilic substitution to give two sets of products: 1-octylimidazole and methylhalide, and 1-methylimidazole and 1-octyl halide. The activation energy of TD at a temperature T, Ea,TD,T, is measured for the nucleophilic substitution of [C8C1Im]I to give Me iodide; Ea,TD,480 = 136 ± 15 kJ mol-1. Ea,TD,T is measured for the nucleophilic substitution of [C8C1Im]Cl to give methylchloride; Ea,TD,455 = 132 ± 10 kJ mol-1. The fact that ΔvapHT and Ea,TD,T are the same (within error) for both ionic liquids is commented upon, and conclusions are drawn as to the thermal stability of these ionic liquids In the experiment, the researchers used many compounds, for example, 1-Octyl-1H-imidazole (cas: 21252-69-7Quality Control of 1-Octyl-1H-imidazole).
1-Octyl-1H-imidazole (cas: 21252-69-7) belongs to imidazole derivatives. Many natural products, especially alkaloids, contain the imidazole ring. These imidazoles share the 1,3-C3N2 ring but feature varied substituents. Many drugs contain an imidazole ring, such as certain antifungal drugs, the nitroimidazole series of antibiotics, and the sedative midazolam.Quality Control of 1-Octyl-1H-imidazole
Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem