• Title/Summary/Keyword: Imidazolium

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Peroxopolyoxotungsten-based Ionic Hybrid as a Highly Efficient Recyclable Catalyst for Epoxidation of Vegetable oil with H2O2

  • Wu, Jianghao;Jiang, Pingping;Qin, Xiaojie;Ye, Yuanyuan;Leng, Yan
    • Bulletin of the Korean Chemical Society
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    • v.35 no.6
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    • pp.1675-1680
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    • 2014
  • A peroxopolyoxotungsten-based ionic hybrid was synthesized by anion-change of peroxopolyoxometalate (POM) $PW_4O{_{24}}^{3-}$ with dicationic long-chain alkyl imidazolium ionic liquids. The characterization was conducted by FT-IR, TGA, $^1H$-NMR and CHN Elemental analyses. Its catalytic performance was evaluated by the epoxidation of soybean oil with $H_2O_2$ under solvent-free condition, including testing of organic cations influence, catalytic reusability and reaction conditions. The catalyst was proved to be a highly efficient recyclable catalyst for epoxidation of various vegetable oils with $H_2O_2$, showing high $H_2O_2$ utilization efficiency, high catalytic activity, convenient recovery and good reuse ability.

Imidazolium Chloride-LiCl Melts as Efficient Solvents for Cellulose

  • Agarwal, Shalu;Hossain, Anwar Md.;Choi, Young-Seop;Cheong, Minserk;Jang, Ho Gyeom;Lee, Je Seung
    • Bulletin of the Korean Chemical Society
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    • v.34 no.12
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    • pp.3771-3776
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    • 2013
  • 1-Alkyl-3-methylimidazolium chloride-LiCl melts were prepared from the reaction of 1-alkyl-3-methylimidazolium chloride ([RMIm]Cl; R=allyl or n-butyl) and lithium chloride, and their ability to dissolve cellulose was evaluated. The solubility of cellulose was greatly increased to 320% when [RMIm]Cl was replaced by [RMIm][$LiCl_2$]. Dissolved cellulose in LiCl/[RMIm]Cl melts was successfully regenerated by adding water and LiCl/[RMIm]Cl melts were easily recovered by removing water. As supported by the computational results, the higher solubility of cellulose in [RMIm][$LiCl_2$] can be ascribed to the increased bond distance between anion and C(2)-H of the imidazolium ring compared with that in [RMIm]Cl, thereby resulting in the increased interaction between $[LiCl_2]^-$ and the hydroxyl groups of cellulose.

Electrochemical Characterization of Lithium Polyelectrolyte Based on Ionic Liquid

  • Cha, E.-H.;Lim, S.-A.;Kim, D.-W.;Choi, N.-S.
    • Journal of the Korean Electrochemical Society
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    • v.12 no.3
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    • pp.271-275
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    • 2009
  • Five novel lithium polyelectrolyte-ionic liquid systems, using poly (lithium 2-acrylamido-2-methyl propanesulfonate; PAMPSLi) were prepared and their electrochemical properties were measured. The ionic conductivity of the PAMPSLi/1-ethyl-3-methylimidazolium tricyano methanide (emImTCM) system was exhibited high conductivity (1.28 $\times$ $10^{-3}$ $S/cm^{-1}$). The high conductivity and low viscosity of PAMPSLi/emImTCM system is due to the high flexibility of imidazolium cation and dissociation of lithium cation from the polymer chains. The PAMPSLi/N,N-dimethyl-N-propyl-Nbutylammonium tricyanomethanide ($N_{1134}TCM$) and PAMPSLi/N, N-dimethyl-N-propyl-N-butylammonium dicyanamide ($N_{1134}DCA$) systems showed fairly high conductivity (6.3 $\times$ $10^{-4}$ $S/cm^{-1}$, 6.0 $\times$ 10.4 S/cm.1). PAMPSLi/Trihexyl (tetradecyl) phosphonium bis (trifluoromethane sulfonyl) amide ($P_{66614}TFSA$) exhibited low conductivity (2.22 $\times$ $10^{-5}$ $Scm^{-1}$) and thermally stable over 400$^{\circ}C$.

Syntheses and Surface Active Properties of Amphoteric Surfactant(4);Syntheses of Sulfonated or Sulfated Derivatives from Imidazoline (양쪽성계면활성제의 유도체합성 및 계면성에 관한 연구(제4보);이미다졸린으로부터 유도된 술폰화 또는 황산화 유도체의 합성)

  • Ro, Y.C.;Kang, Y.S.;Nam, K.D.
    • Journal of the Korean Applied Science and Technology
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    • v.11 no.2
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    • pp.121-127
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    • 1994
  • 1-(2-hydroxyethyl)-2-undecyl-2-imidazoline[I] was converted into various types of sulfonated or sulfated amphoteric surfactants as following. 1-(2-hydroxyethyl)-1-(3-sulfonatedpropyl)-2-undecyl-2-imidazolium[III] 1-(2-sulfatedethyl)-1-methyl-2-undecyl-2-imidazolium[IV] 1-dioxylethylene methyl sulfonated-1-methyl-2-undecyl-2-imidazoliun[V] N-[N'-(2-hydroxyethyl)-N-(3-sulfonatedpropylammonio]ethyl dodecanoyl amide[VI] Mono sodium N-[N'-(2-hydroxyethyl)-N'-disulfonatedpropylammonio]ethyl dodecanoyl amide[VII] N-[N'-(2-hydroxyethyl-N'-(2-hydroxypropl-N'(3-sulfonatedpropyl)ammonio] ethyl dodecanoyl amide[VIII] The alkylimidazolines could be readily hydrolyzed to give amidoamines, but by quaternerization, hydrolysis stability of imidazoline and amide type amphoteric surfactantes were increased in the alkali and acid conditions. Also, at least three carbon chains introduce to the main group, water solubility was sparingly increased.

Effect of the Cation Part of Imidazolium Ionic Liquids on Synthesis of Palladium Particle (팔라듐 입자 제조에 미치는 이미다졸계 이온성액체의 양이온 효과)

  • Kim, Chang Soo;Ahn, Byoung Sung;Tae, Hyunman;Jeon, Seung Hye;Yoo, Kye Sang
    • Applied Chemistry for Engineering
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    • v.23 no.5
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    • pp.510-513
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    • 2012
  • Palladium particles were synthesized by conventional chemical reduction method with ionic liquids. The size and shape of palladium particles were significantly affected by the cation parts of ionic liquids. This is mainly attributed to the different stabilities of the ionic liquid structure formed by the physical bond between the cation parts. Among ionic liquids with [$BF_{4}$] as an anion part, the hexyl substituent in the cation parts was more effective to synthesize palladium particles with the smaller size and more uniform shape.

An Efficient One-Pot Strategies for the Synthesis of [1,3] Oxazine Derivatives ([1,3] Oxazine 유도체 합성을 위한 효율적인 One-Pot 합성)

  • Sapkal, Suryakant B.;Shelke, Kiran F.;Shingate, Bapurao B.;Shingare, Murlidhar S.
    • Journal of the Korean Chemical Society
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    • v.54 no.4
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    • pp.437-442
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    • 2010
  • Sodium hydrogen sulphate ($NaHSO_4$), n-tetra butyl ammonium bromide (TBAB) as a phase transfer catalyst (PTC) in water, and 1-butyl-3-methyl imidazolium hydrogen sulphate [bmim]$HSO_4$ as ionic liquid (IL) has been used as a mild reaction promoter for the cyclocondensation of formalin, ${\beta}$-naphthol and aromatic amines to afford respective 2,3-dihydro-2-phenyl-1H-naphtho-[1,2-e] [1,3] oxazine derivatives. The present protocols are greener, high yielding and involved the nonchromatographic isolation procedure.

Physical and Thermodynamic Properties of Imidazolium Ionic Liquids (이미다졸계 이온성 액체의 물성)

  • Oh, Sooyeoun;Kang, Jeong Won;Park, Byung Heung;Kim, Ki-Sub
    • Korean Chemical Engineering Research
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    • v.50 no.4
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    • pp.708-712
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    • 2012
  • Ionic liquids (ILs) existing as liquid state at room temperature are composed of a immense heterocyclic cation and inorganic anion which is smaller than cation's size. Thus, the species of cation and anion as well as the length of alkyl group on the cation have influence on their physical properties. Their outstanding properties such as non-volatility, thermal stability and wide range of electrochemical stability make these materials excellent candidates for green solvent which can substitute the conventional organic solvents. In this study, ILs based on imidazolium cation have been synthesized such as 1-butyl-3-methylimidazolium bromide ([BMIM][Br]), 1-butyl-3-methylimidazolium chloride ([BMIM] [Cl]), 1-butyl-3-methylimidazolium iodide ([BMIM][I]), and 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][$BF_4$]). The density, viscosity, refractive index, heat capacity and ionic conductivity of [BMIM][Br], [BMIM][I], and [BMIM] [$BF_4$] were measured over range of temperature of 293.2 to 323.2 K. The density and refractive index values of [BMIM][I] were the highest among three ILs and the viscosity values of [BMIM][Br] were the highest among three ILs. The heat capacities [BMIM][$BF_4$] were higher than those of [BMIM][Br]. The ionic conductivities of [BMIM][$BF_4$] were higher than those of [BMIM][I].

Cycloaddition of Carbon Dioxide to Allyl Glycidyl Ether Using Silica-supported Ionic Liquid as a Catalyst (실리카에 고정화된 이온성액체를 촉매로 이용한 알릴글리시딜에테르와 이산화탄소의 부가반응)

  • Shim, Hye-Lim;Lee, Mi-Kyung;Yu, Jeong-In;Park, Dae-Won
    • Clean Technology
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    • v.14 no.3
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    • pp.166-170
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    • 2008
  • In this study, imidazolium salt ionic liquid on amorphous silica was prepared and its catalytic performance in the cycloaddition of $CO_2$ with allyl glycidyl ether (AGE) to produce heterocyclic carbonate was investigated. The ionic liquid was generated on chloropropyl functionalized silica through the immobilization of imidazole. The prepared catalyst was characterized using a number of instrumental analysis including XRD, BET, $^{29}Si$ MAS-NMR and SEM. $^{29}Si$ MAS-NMR showed that the ionic liquid formed adduct with the chloropropyl groups attached to the silica surface. The immobilized ionic liquid showed very good catalytic activity for the cycloaddition of $CO_2$ with AGE, showing 55-61% of AGE conversion with over 85% of the carbonate selectivity at $80-120^{\circ}C$. Its AGE conversion and selectivity to the carbonate were even higher than the homogeneous analog, 1-n-butyl-3-methyl imidazolium bromide (BMImBr).

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