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1.
Ralf Giernoth Priv.‐Doz. Dr. 《Angewandte Chemie (International ed. in English)》2010,49(16):2834-2839
In recent years, ionic liquids have attracted the attention of many chemists as a result of their unique properties as solvents for chemical transformations. The focus of this Minireview is on applications of so‐called “task‐specific” ionic liquids, whereby the role of the ionic liquid goes beyond that of a solvent. Such ionic liquids find application in a wide range of areas, including catalysis, synthesis, gas absorption, and analysis. 相似文献
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Copper(II)‐Specific Fluorogenic Task‐Specific Ionic Liquids as Selective Fluorescence Probes and Recyclable Extractants 下载免费PDF全文
Sobhan Chatterjee Hardipsinh Gohil Dr. E. Suresh Dr. Alok Ranjan Paital 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(40):13943-13948
The designed synthesis of a series of copper(II) specific fluorogenic hydrophobic task‐specific ionic liquids (TSILs) from a new naphthalene‐based tetradentate ligand is reported. Absorption and fluorescence spectral studies reveal both the ligand and its derivative TSILs show exclusive selectivity towards copper(II) ions. The Stern–Volmer method for calculation of the detection limit for ligand and TSIL1–3 shows values of 0.12, 20, 17, and 15 μM , respectively. Extraction and striping studies by doping these TSILs in [bmim][NTf2] demonstrated that these TSILs are recyclable extractants for the selective recovery of CuII ions from a mixture of 14 relevant metal chloride aqueous solutions in biphasic liquid–liquid extraction with approximately 95 % recovery. 相似文献
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Dr. Prasanta K. Mohapatra Arijit Sengupta Mudassir Iqbal Dr. Jurriaan Huskens Dr. Willem Verboom 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(9):3230-3238
Two new diglycolamide‐based task‐specific ionic liquids (DGA? TSILs) were evaluated for the extraction of actinides and lanthanides from acidic feed solutions. These DGA? TSILs were capable of exceptionally high extraction of trivalent actinide ions, such as Am3+, and even higher extraction of the lanthanide ion, Eu3+ (about 5–10 fold). Dilution of the DGA? TSILs in an ionic liquid, C4mim+ ? NTf2?, afforded reasonably high extraction ability, faster mass transfer, and more efficient stripping of the metal ion. The nature of the extracted species was studied by slope analysis, which showed that the extracted species contained one NO3? anion, along with the participation of two DGA? TSIL molecules. Time‐resolved laser fluorescence spectroscopy (TRLFS) analysis showed a strong complexation with no inner‐sphere water molecule in the EuIII? DGA? TSIL complexes in the presence and absence of C4mim+ ? NTf2? as the diluent. The very high radiolytic stability of DGA? TSIL 6 makes it one of the most‐efficient solvent systems for the extraction of actinides under acidic feed conditions. 相似文献
4.
Massimo Fabris Dr. Vittorio Lucchini Prof. Marco Noè Dr. Alvise Perosa Dr. Maurizio Selva Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(45):12273-12282
This article describes 1) a methodology for the green synthesis of a class of methylammonium and methylphosphonium ionic liquids (ILs), 2) how to tune their acid–base properties by anion exchange, 3) complete neat‐phase NMR spectroscopic characterisation of these materials and 4) their application as active organocatalysts for base‐promoted carbon–carbon bond‐forming reactions. Methylation of tertiary amines or phosphines with dimethyl carbonate leads to the formation of the halogen‐free methyl‐onium methyl carbonate salts, and these can be easily anion‐exchanged to yield a range of derivatives with different melting points, solubility, acid–base properties, stability and viscosity. Treatment with water, in particular, yields bicarbonate‐exchanged liquid onium salts. These proved strongly basic, enough to efficiently catalyse the Michael reaction; experiments suggest that in these systems the bicarbonate basicity is boosted by two orders of magnitude with respect to inorganic bicarbonate salts. These basic ionic liquids used in catalytic amounts are better even than traditional strong organic bases. The present work also introduces neat NMR spectroscopy of the ionic liquids as a probe for solute–solvent interactions as well as a tool for characterisation. Our studies show that high catalytic efficacy of functional ionic liquids can be achieved by integrating their green synthesis, along with a fine‐tuning of their structure. Demonstrating that ionic liquid solvents can be made by a truly green procedure, and that their properties and reactivity can be tailored to the point of bridging the gap between their use as solvents and as catalysts. 相似文献
5.
Yanqiang Zhang Dr. Suojiang Zhang Prof. Dr. Xingmei Lu Dr. Qing Zhou Dr. Wei Fan XiangPing Zhang Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(12):3003-3011
CO 2 is locked up : Dual amino‐functionalised phosphonium ionic liquids (ILs; see figure) have been prepared. The ILs have excellent thermal properties, such as low glass transition temperatures and high thermal decomposition temperatures. The supported CO2 absorption of four of the ILs on porous SiO2 was found to approach one mol CO2 per mol IL, a factor of two greater than that reported before.
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Shelbi Parker Radu Reit Haley Abitz Gregory Ellson Kejia Yang Benjamin Lund Walter E. Voit 《Macromolecular rapid communications》2016,37(13):1027-1032
Thiol‐click reactions lead to polymeric materials with a wide range of interesting mechanical, electrical, and optical properties. However, this reaction mechanism typically results in bulk materials with a low glass transition temperature (Tg) due to rotational flexibility around the thioether linkages found in networks such as thiol‐ene, thiol‐epoxy, and thiol‐acrylate systems. This report explores the thiol‐maleimide reaction utilized for the first time as a solvent‐free reaction system to synthesize high‐Tg thermosetting networks. Through thermomechanical characterization via dynamic mechanical analysis, the homogeneity and Tgs of thiol‐maleimide networks are compared to similarly structured thiol‐ene and thiol‐epoxy networks. While preliminary data show more heterogeneous networks for thiol‐maleimide systems, bulk materials exhibit Tgs 80 °C higher than other thiol‐click systems explored herein. Finally, hollow tubes are synthesized using each thiol‐click reaction mechanism and employed in low‐ and high‐temperature environments, demonstrating the ability to withstand a compressive radial 100 N deformation at 100 °C wherein other thiol‐click systems fail mechanically.
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Dr. Mingwei Zhao Dr. Yurong Zhao Prof. Liqiang Zheng Prof. Caili Dai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(3):1076-1081
Highly ordered supramolecular microfibers were constructed through a simple ionic self‐assembly strategy from complexes of the N‐tetradecyl‐N‐methylpyrrolidinium bromide (C14MPB) surface‐active ionic liquid and the small methyl orange (MO) dye molecule, with the aid of patent blue VF sodium salt. By using scanning electron microscopy and polarized optical microscopy, the width of these self‐assembled microfibers is observed to be about 1 to 5 μm and their length is from tens of micrometers to almost a millimeter. The 1H NMR spectra of the microfibers indicates that the supramolecular complexes are composed of C14MPB and MO in equal molar ratio. The electrostatic, hydrophobic, and π–π stacking interactions are regarded as the main driving forces for the formation of microfibers. Furthermore, through characterization by using confocal fluorescence microscopy, the microfibers were observed to show strong fluorescent properties and may find potential applications in many fields. 相似文献
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Tianyi Qin Xuying Li Dr. Jinping Chen Dr. Yi Zeng Dr. Tianjun Yu Prof. Dr. Guoqiang Yang Prof. Dr. Yi Li 《化学:亚洲杂志》2014,9(12):3641-3649
A series of dendritic ionic liquids (DILs) based on imidazolium‐modified poly(aryl ether) dendrimers IL‐Br‐Gn (n=0–3) were synthesized by a modified convergent approach and “click” chemistry. The resulting DILs exhibited high thermal resistance with decomposition temperatures up to 270 °C and low glass transition temperatures in the range of approximately ?5–0 °C. All IL‐Br‐Gn were found to be miscible with water at any ratio and could encapsulate hydrophobic molecules. The reversible phase transfer of the DILs between the aqueous and organic phases was accomplished by simple anion exchange between the hydrophilic Br? anion and the hydrophobic bis(trifluoromethylsulfonyl)amide anion (NTf2?). IL‐Br‐Gn could be used as transporters to shuttle hydrophobic molecules between the organic and aqueous phases efficiently. The present work provides a new kind of transporting materials with potential applications in substance separation, drug delivery, and biomolecule transport. 相似文献
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Liuyi Li Jinyun Wang Tao Wu Prof. Ruihu Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(25):7842-7851
A series of click ionic salts 4 a – 4 n was prepared through click reaction of organic azides with alkyne‐functionalized imidazolium or 2‐methylimidazolium salts, followed by metathesis with lithium bis(trifluoromethanesulfonyl)amide or potassium hexafluorophosphate. All salts were characterized by IR, NMR, TGA, and DSC, and most of them can be classified as ionic liquids. Their steric and electronic properties can be easily tuned and modified through variation of the aromatic or aliphatic substituents at the imidazolium and/or triazolyl rings. The effect of anions and substituents at the two rings on the physicochemical properties was investigated. The charge and orbital distributions based on the optimized structures of cations in the salts were calculated. Reaction of 4 a with PdCl2 produced mononuclear click complex 4 a‐Pd , the structure of which was confirmed by single‐crystal X‐ray diffraction analysis. Suzuki–Miyaura cross‐coupling shows good catalytic stability and high recyclability in the presence of PdCl2 in 4 a . TEM and XPS analyses show formation of palladium nanoparticles after the reaction. The palladium NPs in 4 a are immobilized by the synergetic effect of coordination and electrostatic interactions with 1,2,3‐triazolyl and imidazolium, respectively. 相似文献
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Shun‐Ping Ji Meng Tang Prof. Dr. Ling He Prof. Dr. Guo‐Hong Tao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(14):4452-4461
The hexanitratolanthanate anion (La(NO3)63?) is an interesting symmetric anion suitable to construct the component of water‐free rare‐earth‐metal ionic liquids. The syntheses and structural characterization of eleven lanthanum nitrate complexes, [Cnmim]3[La(NO3)6] (n=1, 2, 4, 6, 8, 12, 14, 16, 18), including 1,3‐dimethylimidazolium hexanitratolanthanate ([C1mim]3[La(NO3)6], 1 ), 1‐ethyl‐3‐methylimidazolium hexanitratolanthanate ([C2mim]3[La(NO3)6], 2 ), 1‐butyl‐3‐methylimidazolium hexanitratolanthanate ([C4mim]3[La(NO3)6], 3 ), 1‐isobutyl‐3‐methylimidazolium hexanetratolanthanate ([isoC4mim]3[La(NO3)6], 4 ), 1‐methyl‐3‐(3′‐methylbutyl)imidazolium hexanitratolanthanate ([MC4mim]3[La(NO3)6], 5 ), 1‐hexyl‐3‐methylimidazolium hexanitratolanthanate ([C6mim]3[La(NO3)6], 6 ), 1‐methyl‐3‐octylimidazolium hexanitratolanthanate ([C8mim]3[La(NO3)6], 7 ), 1‐dodecyl‐3‐methylimidazolium hexanitratolanthanate ([C12mim]3[La(NO3)6], 8 ), 1‐methyl‐3‐tetradecylimidazolium hexanitratolanthanate ([C14mim]3[La‐(NO3)6], 9 ), 1‐hexadecyl‐3‐methylimid‐azolium hexanitratolanthanum ([C16dmim]3[La(NO3)6], 10 ), and 1‐methyl‐3‐octadecylimidazolium hexanitratolanthanate ([C18mim]3[La(NO3)6], 11 ) are reported. All new compounds were characterized by 1H and 13C NMR, and IR spectroscopy as well as elemental analysis. The crystal structure of compound 1 was determined by using single‐crystal X‐ray diffraction, giving the following crystallographic information: monoclinic; P21/c; a=15.3170 (3), b=14.2340 (2), c=13.8954(2) Å; β=94.3453(15)°, V=3020.80(9) Å3, Z=4, ρ=1.764 g cm?3. The coordination polyhedron around the lanthanum ion is rationalized by six nitrate anions with twelve oxygen atoms. No hydrogen‐bonding network or water molecule was found in 1 . The thermodynamic stability of the new complexes was investigated by using thermogravimetric analysis (TGA). The water‐free hexanitratolanthanate ionic liquids are thermal and moisture stable. Four complexes, namely complexes 8 – 11 , were found to be ionic liquid crystals by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). They all present smectic A liquid‐crystalline phase. 相似文献
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Dzmitry S. Firaha Dr. Oldamur Hollóczki Prof. Dr. Barbara Kirchner 《Angewandte Chemie (International ed. in English)》2015,54(27):7805-7809
Ionic liquids (ILs), vary strongly in their interaction with CO2. We suggest simple theoretical approach to predict the CO2 absorption behavior of ILs. Strong interaction of the CO2 with the IL anions corresponds to chemical absorption whereas weak interaction indicates physical absorption. A predictive estimate with a clear distinction between physical and chemical absorption can be simply obtained according to geometries optimized in the presence of a solvation model instead of optimizing it only in gas phase as has been done to date. The resulting Gibbs free energies compare very well with experimental values and the energies were correlated with experimental capacities. Promising anions, for ionic liquids with reversible CO2 absorption properties can be defined by a reaction Gibbs free energy of absorption in the range of ?30 to 16 kJ mol?1. 相似文献
14.
Ivan Guryanov Dr. Francesca Maria Toma Dr. Alejandro Montellano López Dr. Mauro Carraro Dr. Tatiana Da Ros Dr. Guido Angelini Dr. Eleonora D'Aurizio Dr. Antonella Fontana Prof. Michele Maggini Prof. Maurizio Prato Prof. Marcella Bonchio Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(46):12837-12845
The effect of microwave (MW) irradiation and ionic liquids (IL) on the cycloaddition of azomethine ylides to [60]fullerene has been investigated by screening the reaction protocol with regard to the IL medium composition, the applied MW power, and the simultaneous cooling of the system. [60]Fullerene conversion up to 98 % is achieved in 2–10 min, by using a 1:3 mixture of the IL 1‐methyl‐3‐n‐octyl imidazolium tetrafluoroborate ([omim]BF4) and o‐dichlorobenzene, and an applied power as low as 12 W. The mono‐ versus poly‐addition selectivity to [60]fullerene can be tuned as a function of fullerene concentration. The reaction scope includes aliphatic, aromatic, and fluorous‐tagged (FT) derivatives. MW irradiation of IL‐structured bucky gels is instrumental for the functionalization of single‐walled carbon nanotubes (SWNTs), yielding group coverages of up to one functional group per 60 carbon atoms of the SWNT network. An improved performance is obtained in low viscosity bucky gels, in the order [bmim]BF4> [omim]BF4> [hvim]TF2N (bmim=1‐methyl‐3‐n‐butyl imidazolium; hvim=1‐vinyl‐3‐n‐hexadecyl imidazolium). With this protocol, the introduction of fluorous‐tagged pyrrolidine moieties onto the SWNT surface (1/108 functional coverage) yields novel FT‐CNS (carbon nanostructures) with high affinity for fluorinated phases. 相似文献
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Dr. Ulrich Preiss Dr. Vladimir N. Emel'yanenko Prof. Dr. Sergey P. Verevkin Dr. Daniel Himmel Dr. Yauheni U. Paulechka Prof. Dr. Ingo Krossing 《Chemphyschem》2010,11(16):3425-3431
Modeling of the temperature‐dependent liquid entropy of ionic liquids (ILs) with great accuracy using COSMO‐RS is demonstrated. The minimum structures of eight IL ion pairs are investigated and the entropy, calculated from ion pairs, is found to differ on average only 2 % from the available experimental values (119 data points). For calculations with single ions, the average error amounts to 2.6 % and stronger‐coordinating ions tend to give higher deviations. Additionally, the first parameterization of the standard liquid entropy for ILs is presented in the context of traditional volume‐based thermodynamics (Sl0=1.585 kJ mol?1 K?1 nm?3?rm3+14.09 J mol?1 K?1), which sheds light on the statistical treatment of ionic interactions. The findings provide the first direct access to accurate predictions of liquid entropies of ILs, which are tedious and time‐consuming to measure. 相似文献
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Cedric Maton Dr. Neil R. Brooks Prof. Dr. Luc Van Meervelt Prof. Dr. Koen Binnemans Dr. Stijn Schaltin Prof. Dr. Jan Fransaer Prof. Dr. Christian V. Stevens 《Chemphyschem》2013,14(15):3503-3516
Novel peralkylated imidazolium ionic liquids bearing alkoxy and/or alkenyl side chains have been synthesized and studied. Different synthetic routes towards the imidazoles and the ionic liquids comprising bromide, iodide, methanesulfonate, bis(trifluoromethylsulfonyl)imide ([NTf2]?), and dicyanamide {[N(CN)2]?} as the anion were evaluated, and this led to a library of analogues, for which the melting points, viscosities, and electrochemical windows were determined. Incorporation of alkenyl moieties hindered solidification, except for cations with high symmetry. The alkoxy‐derivatized ionic liquids are often crystalline; however, room‐temperature ionic liquids (RTILs) were obtained with the weakly coordinating anions [NTf2]? and [N(CN)2]?. For the viscosities of the peralkylated RTILs, an opposite trend was found, that is, the alkoxy derivatives are less viscous than their alkenyl‐substituted analogues. Of the crystalline compounds, X‐ray diffraction data were recorded and related to their molecular properties. Upon alkoxy substitution, the electrochemical cathodic limit potential was found to be more positive, whereas the complete electrochemical window of the alkenyl‐substituted imidazolium salts was shifted to somewhat more positive potentials. 相似文献
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Peter Nockemann Dr. Ben Thijs Dr. Kyra Lunstroot Dr. Tatjana N. Parac‐Vogt Prof. Dr. Christiane Görller‐Walrand Prof. Dr. Koen Binnemans Prof. Dr. Kristof Van Hecke Dr. Luc Van Meervelt Prof. Dr. Sergey Nikitenko John Daniels Dr. Christoph Hennig Dr. Rik Van Deun Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(6):1449-1461
The dissolution process of metal complexes in ionic liquids was investigated by a multiple‐technique approach to reveal the solvate species of the metal in solution. The task‐specific ionic liquid betainium bis(trifluoromethylsulfonyl)imide ([Hbet][Tf2N]) is able to dissolve stoichiometric amounts of the oxides of the rare‐earth elements. The crystal structures of the compounds [Eu2(bet)8(H2O)4][Tf2N]6, [Eu2(bet)8(H2O)2][Tf2N]6?2H2O, and [Y2(bet)6(H2O)4][Tf2N]6 were found to consist of dimers. These rare‐earth complexes are well soluble in the ionic liquids [Hbet][Tf2N] and [C4mim][Tf2N] (C4mim=1‐butyl‐3‐methylimidazolium). The speciation of the metal complexes after dissolution in these ionic liquids was investigated by luminescence spectroscopy, 1H, 13C, and 89Y NMR spectroscopy, and by the synchrotron techniques EXAFS (extended X‐ray absorption fine structure) and HEXS (high‐energy X‐ray scattering). The combination of these complementary analytical techniques reveals that the cationic dimers decompose into monomers after dissolution of the complexes in the ionic liquids. Deeper insight into the solution processes of metal compounds is desirable for applications of ionic liquids in the field of electrochemistry, catalysis, and materials chemistry. 相似文献
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Dr. Qinghua Zhang Dr. Ping Yin Dr. Jiaheng Zhang Prof. Dr. Jean'ne M. Shreeve 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(23):6909-6914
In propellant systems, the most common bipropellants are composed of two chemicals, a fuel (or reducer) and an oxidizer. Currently, the choices for propellant fuels rely mainly on hydrazine and its methylated derivatives, even though they are extremely toxic, highly volatile, sensitive to adiabatic compression (risk of detonation), and, therefore, difficult to handle. With this background, the search for alternative green propellant fuels has been an urgent goal of space science. In this study, a new family of cyanoborohydride‐based ionic liquids (ILs) with properties and performances comparable to hydrazine derivatives were designed and synthesized. These new ILs as bipropellant fuels, have some unique advantages including negligible vapor pressure, ultra‐short ignition delay (ID) time, and reduced synthetic and storage costs, thereby showing great application potential as environmentally friendly fuels in bipropellant formulations. 相似文献