820972-34-7Relevant articles and documents
Anion Analysis of Ionic Liquids and Ionic Liquid Purity Assessment by Ion Chromatography
Rutz, Christina,Schmolke, Laura,Gvilava, Vasily,Janiak, Christoph
supporting information, p. 130 - 135 (2017/02/05)
The simultaneous determination of halide impurities (fluoride, chloride, bromide, and iodide) and ionic liquid (IL) anions (tetrafluoroborate, hexafluorophosphate, and triflimide) using ion chromatography was developed with a basic, non-gradient ion chromatography system. The non-gradient method uses the eluent Na2CO3/NaHCO3in water/acetonitrile (70:30 v:v) on the AS 22 column to enable a rapid and simultaneous analysis of different IL and halide anions within an acceptable run-time (22 min) and with good resolution R of larger than 2.4, a capacity k′ between 0.4 and 5.1, selectivities α between 1.3 and 2.1, and peak asymmetries Asof less than 1.5. Halide impurities below 1 ppm (1 mg·L–1of prepared sample solution) could be quantified. A range of ionic liquids with tetrafluoroborate [BF4]–, hexafluorophosphate [PF6]–, and bis(trifluoromethylsulfonyl)imide (triflimide) [NTf2]–anions combined with cations based on imidazole, pyridine, and tetrahydrothiophene could be analyzed for their anion purity. The IL-cations do not influence the chromatographic results. With the analysis of 18 ILs differing in their cation-anion combination we could prove the general applicability of the described method for the anion purity analysis of ionic liquids with respect to halide ions. The IL-anion purity of most ILs was above 98 wt %. The highest IL-anion purity was 99.8 wt %, implying anion impurities of only 0.2 wt %. The used halide anion from the synthesis route was the major anion impurity, yet with chloride also bromide and fluoride (potentially from hydrolysis of [BF4]–) were often detected. When iodide was used, at least chloride but sometimes also bromide and fluoride was present. However, even if the IL-anion content is above 99 wt %, it does not necessarily indicate an ionic liquid devoid of other impurities. From the IC analysis, one can also deduce a possible cation impurity if one takes into account the expected (calculated) IL-anion content. A matching experimental and theoretical IL-anion content excludes, a higher experimental content indicates the presence of residual KBF4, NH4PF6, or LiNTf2salt from the halide to IL-anion exchange.
A polyoxometalate-based PdII-coordinated ionic solid catalyst for heterogeneous aerobic oxidation of benzene to biphenyl
Zhao, Pingping,Leng, Yan,Zhang, Mingjue,Wang, Jun,Wu, Yajing,Huang, Jun
supporting information; experimental part, p. 5721 - 5723 (2012/07/28)
An ionic solid catalyst by pairing Keggin polyoxometalate-anions with PdII-coordinated nitrile-tethered ionic liquid cations was synthesized, characterized, and tested for aerobic oxidation of benzene to biphenyl. A unique heterogeneous intramolecular electron transfer mechanism is proposed to understand its high activity.
Sulphonyl-1,2,4-triazole salts
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Page/Page column 43-44, (2011/04/24)
The invention relates to triazole salts, to their preparation and to applications thereof. The salts have at least one anionic triazolium group which carries at least one chlorosulphonyl, fluorosulphonyl or alkoxyfluorosulphonyl group, each of the anionic groups being combined with a proton or a cation that has a valency of less than or equal to 4. The salts are useful as synthesis reagents, as chemical-reaction or polymerization catalysts, and as ion-conducting materials for electrochemical generators, supercapacitors and electrochromic devices.
Palladium-catalyzed desulfitative Mizoroki-Heck coupling reactions of sulfonyl chlorides with olefins in a nitrile-functionalized ionic liquid
Dubbaka, Srinivas Reddy,Zhao, Dongbin,Fei, Zhaofu,Volla, Chandra M. Rao,Dyson, Paul J.,Vogel, Pierre
, p. 3155 - 3157 (2008/02/13)
Aryl and alkenyl sulfonyl chlorides can be used in Heck-Mizoroki-type couplings with mono- and disubstituted olefins in a nitrile-functionalized ionic liquid, viz. [C3CNpy] [Tf2N]. Advantages over previously reported methods include: (1) use of a cheap catalyst source, PdCl2, (2) ability to handle the catalyst in air, (3) reduced reaction times, (4) elimination of phase-transfer catalysts due to the high solubility of the inorganic base in the ionic liquid, and (5) facile recycling of the ionic liquid-palladium catalyst. The yields of coupling products remain in the same range as the reactions conducted in organic solvents. Palladium nanoparticles, characterized using transmission electron microscopy, have been identified in the ionic liquid following the Heck-Mizoroki type coupling reactions. Georg Thieme Verlag Stuttgart.
Nitrile-functionalized pyridinium ionic liquids: Synthesis, characterization, and their application in carbon-carbon coupling reactions
Zhao, Dongbin,Fei, Zhaofu,Geldbach, Tilmann J.,Scopelliti, Rosario,Dyson, Paul J.
, p. 15876 - 15882 (2007/10/03)
A series of relatively low-cost ionic liquids, based on the N-butyronitrile pyridinium cation [C3CNpy]+, designed to improve catalyst retention, have been prepared and evaluated in Suzuki and Stille coupling reactions. Depending on the nature of the anion, these salts react with palladium chloride to form [C3CNPy]2[PdCl4] when the anion is Cl- and complexes of the formula [PdCl 2(C3CNpy)2][anion]2 when the anion is PF6-, BF4-, or N(SO 2CF3)2-. The solid-state structures of [C3CNpy]Cl and [C3CNpy]2[PdCl4] have been established by single-crystal X-ray diffraction. The catalytic activity of these palladium complexes following immobilization in both N-butylpyridinium and nitrile-functionalized ionic liquids has been evaluated in Suzuki and Stille coupling reactions. All of the palladium complexes show good catalytic activity, but recycling and reuse is considerably superior in the nitrile-functionalized ionic liquid. Inductive coupled plasma spectroscopy reveals that the presence of the coordinating nitrile moiety in the ionic liquid leads to a significant decrease in palladium leaching relative to simple N-alkylpyridinium ionic liquids. Palladium nanoparticles have been identified as the active catalyst in the Stille reaction and were characterized using transmission electron microscopy.