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991.
992.
A novel ionic compound [Fe(CN)6(PhCH2NC9H7)4]·12H2O (C70H80FeN10O12, Mr = 1309.29) has been synthesized and its structure was characterized by IR, elemental analysis and X-ray diffraction. The compound crystallizes in triclinic, space group P1, with a = 10.968(7), b = 11.466(7), c = 14.077(8) , α = 87.014(7), β = 78.124(7), γ = 72.708(7)o, V = 1654.1(17) 3, Z = 1, Dc = 1.314 g·cm–3, F(000) = 692, μ = 0.298 mm–1, the final R = 0.0519 and wR = 0.1355. The building unit of the title compound consists of four (PhCH2N+C9H7) ions, one [Fe(CN)6]4– anion, and a dozen water molecules. According to the structural analysis, [Fe(CN)6]4– ions are linked together by O–H···O and O–H···N hydrogen bonds, while (PhCH2N+C9H7) and [Fe(CN)6]4– ions interact with each other by electrostatic force to form an ionic compound. 相似文献
993.
Jafar Akbari 《Tetrahedron letters》2009,50(29):4236-4238
A sulfonic acid functionalized ionic liquid is used as a Brønsted acid catalyst for the one-pot, three-component synthesis of α-aminophosphonates from aldehydes and ketones at room temperature in water. This homogeneous catalytic procedure is simple and efficient and the catalyst can be reused at least six times without any noticeable decrease in catalytic activity. 相似文献
994.
Dmitriy E. Siyutkin 《Tetrahedron》2009,65(7):1366-1979
New chiral ionic liquids bearing proline, serine or threonine moieties were synthesized. Compounds that contain 1-dodecylimidazolium or 4-(5-n-nonyl)-pyridinium cations and NTf2 or PF6 anions efficiently catalyze the asymmetric aldol reaction between aldehydes and ketones in the presence of water to generate aldols with high distereo- (up to 98:2) and enantioselectivity (up to >99% ee). 4-Hydroxyproline modified by the 4-(5-n-nonyl)-pyridinium hexafluorophosphate moiety retains its activity and selectivity over at least eight reaction cycles. 相似文献
995.
Markus Döbbelin Cristina Pozo‐Gonzalo Rebeca Marcilla Raúl Blanco José L. Segura Jose A. Pomposo David Mecerreyes 《Journal of polymer science. Part A, Polymer chemistry》2009,47(12):3010-3021
Novel poly(3,4‐ethylenedioxythiophene) (PEDOT) polymers bearing imidazolium‐ionic liquid moieties were synthesized by electrochemical polymerizations. For this purpose, new functional monomers were synthesized having an 3,4‐ethylenedioxythiophene (EDOT) unit and an imidazolium‐ionic liquid with different anions such as tetrafluoroborate (BF), bis(trifluoromethane)sulfonimide ((CF3SO2)2N?), and hexafluorophosphate (PF). Next, polymer films were obtained by electrochemical synthesis in dicholoromethane solutions. Obtained polymers were characterized, revealing the characteristics of PEDOT in terms of electrochemical and spectroelectrochemical properties, FTIR, 1H NMR, and AFM microscopy. Interestingly, the hydrophobic character of electropolymerized films could be modified depending on the anion type. The hydrophobicity followed the trend PF > (CF3SO2)2N? > BF > pure PEDOT as determined by water contact angle measurements. Furthermore, the polymers could be dissolved in a range of polar organic solvents such as dimethylformamide, propylene carbonate, and dimethyl sulfoxide making these polymers interesting candidates for wet processing methods. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3010–3021, 2009 相似文献
996.
Steven J. Craythorne Kris Anderson Dr. Fabio Lorenzini Christina McCausland Emily F. Smith Peter Licence Dr. Andrew C. Marr Dr. Patricia C. Marr Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(29):7094-7100
Molecular hydrogenation catalysts have been co‐entrapped with the ionic liquid [Bmim]NTf2 inside a silica matrix by a sol–gel method. These catalytic ionogels have been compared to simple catalyst‐doped glasses, the parent homogeneous catalysts, commercial heterogeneous catalysts, and Rh‐doped mesoporous silica. The most active ionogel has been characterised by transmission electron microscopy, X‐ray photoelectron spectroscopy, and solid state NMR before and after catalysis. The ionogel catalysts were found to be remarkably active, recyclable and resistant to chemical change. 相似文献
997.
Wenwen Tu Jianping Lei Dr. Huangxian Ju Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(3):779-784
A functional composite of single‐walled carbon nanotubes (SWNTs) with hematin, a water‐insoluble porphyrin, was first prepared in 1‐butyl‐3‐methylimidazolium hexafluorophosphate ([BMIM][PF6]) ionic liquid. The novel composite in ionic liquid was characterized by scanning electron microscopy, ultraviolet absorption spectroscopy, and electrochemical impedance spectroscopy, and showed a pair of direct redox peaks of the FeIII/FeII couple. The composite–[BMIM][PF6]‐modified glassy carbon electrode showed excellent electrocatalytic activity toward the reduction of trichloroacetic acid (TCA) in neutral media due to the synergic effect among SWNTs, [BMIM][PF6], and porphyrin, which led to a highly sensitive and stable amperometric biosensor for TCA with a linear range from 9.0×10?7 to 1.4×10?4 M . The detection limit was 3.8×10?7 M at a signal‐to‐noise ratio of 3. The TCA biosensor had good analytical performance, such as rapid response, good reproducibility, and acceptable accuracy, and could be successfully used for the detection of residual TCA in polluted water. The functional composite in ionic liquid provides a facile way to not only obtain the direct electrochemistry of water‐insoluble porphyrin, but also construct novel biosensors for monitoring analytes in real environmental samples. 相似文献
998.
David B. Cordes Dr. Marcin Smiglak Dr. C. Corey Hines Nicholas J. Bridges Dr. Meghna Dilip Dr. Geetha Srinivasan Dr. Andreas Metlen Dr. Robin D. Rogers Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(48):13441-13448
New, potentially green, and efficient synthetic routes for the remediation and/or re‐use of perchlorate‐based energetic materials have been developed. Four simple organic imidazolium‐ and phosphonium‐based perchlorate salts/ionic liquids have been synthesized by simple, inexpensive, and nonhazardous methods, using ammonium perchlorate as the perchlorate source. By appropriate choice of the cation, perchlorate can be incorporated into an ionic liquid which serves as its own electrolyte for the electrochemical reduction of the perchlorate anion, allowing for the regeneration of the chloride‐based parent ionic liquid. The electrochemical degradation of the hazardous perchlorate ion and its conversion to harmless chloride during electrolysis was studied using IR and 35Cl NMR spectroscopies. 相似文献
999.
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
1000.
David J. Heldebrant Dr. Clement R. Yonker Dr. Philip G. Jessop Dr. Lam Phan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(31):7619-7627
CO2‐binding organic liquids (CO2BOLs) are mixtures of a base (typically an amidine or guanidine) and an alcohol, and have been shown to reversibly capture and release CO2 with low reaction energies and high gravimetric CO2 capacity. We now report the ability of such liquid blends to chemically bind and release other acid gases such as CS2, COS, and SO2 analogously to CO2. These systems bind with sulfur‐containing acid gases to form colored ionic liquids with new O‐alkylxanthate, O‐alkylthiocarbonyl, and O‐alkylsulfite anions. The capture and thermal stripping of each acid gas from these systems and their applicability towards flue gas desulfurization is discussed. 相似文献