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1.
Junhua Chen 《Journal of organometallic chemistry》2006,691(3):470-474
Four novel hexadentate imidazolium salts were synthesized from hexakis(bromomethyl)benzene and 1-substituted imidazole. The arylation of aldehydes with arylboronic acids was effected conveniently and in high yields by a catalyst system generated in situ from these hexadentate imidazolium salts, [Rh(COD)Cl]2 and a base. 相似文献
2.
A fluorogenic probe for bacteria imaging was reported. The binding with anionic bacterial surfaces disassembled the self-assembly probe to turn-on the fluorescence and shift pyrene monomer/excimer ratiometric signals. 相似文献
3.
氯化1-乙基-3-甲基烷基咪唑分子结构及其氢键作用能的密度泛函研究 总被引:1,自引:0,他引:1
采用量子化学密度范函方法计算研究了氯化1-乙基-3-甲基咪唑盐([EMIM]C1)正负离子间相互作用的平衡构型和Cl^-离子从不同方位与咪唑阳离子的结合能.计算发现Cl^-可在咪唑环平面上结合形成离子键,其结合能为.368.97kJ/mol,还可与环上的三个H原子形成氢键,其氢键键长和结合能分别为0.2000nm/-378.03kJ/mol、0.2339nm/-344,69kJ/mol和0.2301nm/-346,01kJ/mol.结合能包括氢键作用能和正负离子的静电作用能,后者为主要贡献.从理论上展示了该离子液体的氢键结构. 相似文献
4.
Bile acid-based acyclic receptors bearing two imidazole and benzimidazole moieties have been synthesized. Anion binding studies using 1H NMR revealed that imidazolium receptor exhibits high selectivity for chloride ion while benzimidazolium receptor showed selectivity for Y-shaped acetate ion through hydrogen bond interactions involving imidazolium C-2 and acetyl methylene hydrogens. 相似文献
5.
Thermal degradation studies of alkyl-imidazolium salts and their application in nanocomposites 总被引:1,自引:0,他引:1
Walid H Awad Jeffrey W Gilman Marc Nyden Thomas E Sutto Paul C Trulove Douglas M Fox 《Thermochimica Acta》2004,409(1):3-11
Increasing the thermal stability of organically-modified layered silicates is one of the key points in the successful technical application of polymer-layered silicate nanocomposites on the industrial scale. To circumvent the detrimental effect of the lower thermal stability of alkyl ammonium-treated montmorillonite, a series of alkyl-imidazolium molten salts were prepared and characterized by elemental analysis, thermogravimetry (TGA) and thermal desorption mass spectroscopy (TDMS). The effect of counter ion, alkyl chain length and structural isomerism on the thermal stability of the imidazolium salts was investigated. Alkyl-imidazolium-treated montmorillonite clays were prepared by ion exchange of the imidazolium salts with Na-montmorillonite. These organically-modified clays were characterized by X-ray diffraction (XRD), TDMS and thermogravimetry coupled with Fourier transform infrared spectroscopy (TGA-FTIR), and compared to the conventional quaternary alkyl ammonium montmorillonite. Results indicate that the counter ion has an effect on the thermal stability of the imidazolium salts, and that imidazolium salts with PF6−, N(SO2CF3)2− and BF4− anions are thermally more stable than the halide salts. A relationship was observed between the chain length of the alkyl group and the thermo-oxidative stability; as the chain length increased from propyl, butyl, decyl, hexadecyl, octadecyl to eicosyl, the stability decreased. The results also show that the imidazolium-treated montmorillonite has greater thermal stability compared to the imidazolium halide. Analysis of the decomposition products by FTIR provides an insight about the decomposition products which are water, carbon dioxide and hydrocarbons. 相似文献
6.
Increased paraoxon detection by acetylcholinesterase inactivation with ionic liquid additives 总被引:1,自引:0,他引:1
This is the first study using ionic liquids (ILs) as additive in the aqueous solvent medium for detection of paraoxon by acetylcholinesterase inhibition method. A systematic comparison of various ILs with organic solvents has been made. The aqueous buffer solution containing ionic liquid ethylpyridinium hexafluorophosphate [EtPy]+[PF6]− has been found to give the best results. The inhibition kinetic follows the first order model. Ionic liquids modified aqueous solutions show the potential to provide a promising and effective medium in detection of paraoxon with acetylcholinesterase. 相似文献
7.
The benzoin reaction, catalyzed by simple 1-N-alkyl-3-methylimidazolium salt-based ionic liquid via carbene intermediate, to give the α-hydroxyl ketone proceeds in CH2Cl2 under mild conditions. 相似文献
8.
Xin Wang 《Journal of organometallic chemistry》2005,690(12):2934-2940
Preparation of two imidazolium salts, two monomeric nickel(II) and one cobalt(II) complexes bearing imidazolium ligands is described, The solid-state structures of these compounds have determined by single-crystal X-ray diffraction. After activation with methylaluminoxane (MAO) the nickel complexes show moderate catalytic activities of up to 6 × 105 g PE mol−1Ni h−1 for polymerization of ethylene. Catalytic activities, molecular weights have been investigated under the various reaction conditions. 相似文献
9.
Jong-Ho Kim 《Tetrahedron letters》2004,45(30):5827-5831
A poly(imidazoliummethyl styrene)-surface grafted-polystyrene resin was prepared by suspension polymerization. This was used as the polymer-supported carbene precursor for the palladium complex, which efficiently catalyzed the Suzuki cross-coupling of aryl halides and phenylboronic acid. 相似文献
10.
Shih‐Kang Fu 《合成通讯》2013,43(14):2059-2067
A direct alkylation of a substituted imidazole to prepare the corresponding functionalized ionic liquid has been developed in excellent yields under microwave irradiation. 相似文献