1-Hydroxyimidazole-3-oxides (2-H, 2-Me) were alkylated with (RO) 2 SO 2 (R = Me, Et) to give the new 1,3-di(alkyloxy)imidazolium cations which were isolated as hexafluorophosphates. Ion metathesis yielded new hydrophobic ionic liquids (bis(trifluoromethanesulfonyl)imides, tris(pentafluoroethyl)trifluorophosphates). Bromination afforded 2-bromo derivatives which were converted to Ni and Pd N-heterocyclic carbene complexes by oxidative insertion. Fifteen crystal structures were determined by X-ray diffraction. The N-alkyloxy groups are twisted out of the imidazole ring plane and adopt either syn or anti conformations in the solid state.

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The potential of ionic liquids as solvents for headspace gas chromatography was investigated. Three compounds with boiling points above 200 degrees C were selected to demonstrate the feasibility of the concept described. 2-Ethylhexanoic acid, formamide, and tri-n-butylamine as examples of acidic, neutral, and basic analytes were dissolved in acidic 1-n-butyl-3-methylimidazolium hydrogen sulfate (1), neutral 1-n-butyl-2,3-dimethylimidazolium dicyanamide (2), and 2 containing 1,8-diazabicyclo[5.4.0]undec-7-ene to adjust basic conditions. All analytes could be determined with limits of detection and limits of quantification in the low-ppm concentration range.

Functionalized quaternary imidazolium salts were prepared with the intention to obtain new ionic liquids (ILs). Thus, more than forty 3-alkoxy-1-alkylimidazolium salts, 3-alkoxy-1-alkyl-2-methylimidazolium salts, 1-methylimidazole 3-oxide and 1,2-dimethylimidazole 3-oxide as well as their salts, 1,3-dihydroxyimidazolium salts and 1,3-dihydroxy-2-methylimidazolium salts were synthesized and characterized by spectroscopy and, to a limited extent, by viscosity and conductivity measurements. Results of fourteen single crystal X-ray structure determinations are reported, among them also the parent compounds 1-hydroxyimidazole 3-oxide and 1-hydroxy-2-methylimidazole 3- oxide. Selective debenzylation of 1-benzyloxy-3-methyl imidazolium salts and mono-demethoxylation of 1,3-dimethoxyimidazolium salts were achieved by hydrogenolysis. In addition, a crystalline semiperhydrate of 1,2-dimethylimidazole was characterized. Furthermore, an addition compound of 1-methylimidazole 3-oxide with tris(2-thienyl)borane and a silver carbene complex derived from 1-benzyloxy-3-methylimidazolium hexafluorophosphate was crystallized and characterized.

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