65039-07-8Relevant articles and documents
Synthesis and characterization of oligomeric and polymeric silver-imidazol-2-ylidene iodide complexes
Chen, Wanzhi,Liu, Fenghui
, p. 5 - 12 (2003)
Reaction of N,N′-dimethylimidazolium iodide with Ag2O in CH2Cl2 leads to the coordination polymer [Ag(carbene)2]2[Ag4I6] (2), which consists of the cation [Ag(carbene)2]+ and anionic infinite one-dimensional [Ag4I6] 2- chain. The cations and anionic chains are connected into two-dimensional network structure. Treatment of N-allyl-N′-methylimidazolium iodide with Ag2O yielded a tetranuclear N-heterocyclic carbene silver complex [Ag(carbene)2]2 [Ag2I4] (3). The polymeric [Ag(carbene)] [AgI2] (4) was isolated when the tetranuclear complex 3 was heated at 80 °C. The monocarbene complex 4 adopts infinite one-dimensional ribbon stair structure in which the silver atoms are held together by multiple iodide bridges and weak Ag?Ag interaction. The compounds have been fully characterized by elemental analysis, NMR spectroscopy, and X-ray crystallography.
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.
