1-butyl-3-methylimidazolium perchlorate([BMIM]ClO4) was synthesized by two steps with N-methylimidazolium.Some physico-chemical properties,such as density,surface tension,viscosity,electrical conductivity as well as e...1-butyl-3-methylimidazolium perchlorate([BMIM]ClO4) was synthesized by two steps with N-methylimidazolium.Some physico-chemical properties,such as density,surface tension,viscosity,electrical conductivity as well as electrochemical window,were investigated and solvent performance was also studied.The results show that this kind of ionic liquid is an excellent electrolyte with low viscosity,high electrical conductivity and wide electrochemical window.In addition,[BMIM]ClO4 is soluble in most conventional solvents and some metal oxides have high solubility in it,which lays the foundation of direct electrolysis of metal oxides in this ionic liquid.展开更多
Poly[ 2, 2-（m.phenylene） -5, 5-bibenzimidazole] （mPBI） were synthesized by mixing 3, 3＇, 4, 4＇-tetraaminobiphenyl and isophthallc acid in 1 -butyl-3 -methyUmidazolinm chloride （ E BMIM] CI）. Intrinsic viscosit...Poly[ 2, 2-（m.phenylene） -5, 5-bibenzimidazole] （mPBI） were synthesized by mixing 3, 3＇, 4, 4＇-tetraaminobiphenyl and isophthallc acid in 1 -butyl-3 -methyUmidazolinm chloride （ E BMIM] CI）. Intrinsic viscosity of mPBI polymers was 0.67 dL/g which was measured in 96% sulfuric acid. The polymer was characterized by Fourier transform infrared spectroscopy （FTIR）, nuclear magnetic resonance （ 1H-NMR ）, and thermogravimetric analysis （TGA）. The effects of polymerization conditions on the intrinsic viscosity of mPBI were investigated. It showed that the molecular weight of polymer mainly depended on pre-reaction time and reaction temperature. Comparison of structure and properties of mPBI synthesized in ionic liquids（ILs） and polyphosphoric acid was also reported. It indicates that the ionic liquids are a kind of good solvents in synthesis process of m_PBI and ionic liquids mainly affect molecular weight of mPBL展开更多
The geometries of reactant, product and transition state of the title reaction have been optimized by using density functional theory (DFT) at the B3LYP/6-31G(d,p) and B3LYP/6- 311++G(d,p) levels. The variations of th...The geometries of reactant, product and transition state of the title reaction have been optimized by using density functional theory (DFT) at the B3LYP/6-31G(d,p) and B3LYP/6- 311++G(d,p) levels. The variations of the bond parameters in the course of reaction were analyzed. The zero point energy corrections were performed by vibrational analysis. The equilibrium states and the transition state were verified according to the number of virtue frequency of geometry. The intrinsic reaction coordinates (IRC) were calculated from the transition state. The calculated results show that the double bond rearrangement of butene catalyzed by 1-butyl-3-methyl-imidazolium cation is a one-step reaction. The forward energy barrier of isomerization from 1-butene to 2- butene is about 193 kJ·mol-1 and the reverse energy barrier about 209 kJ·mol-1 at the B3LYP/6- 31G(d,p) level, which means that the reaction is easy to proceed at or above room temperature.展开更多
The density functional theory （DFT） has been employed to investigate the electronic structures ofEMIM^＋（1-ethyl-3-methylimidazolium＋）, CuCl2^-, Cu2Cl3^- and EMIM^＋-CuCl2^-, EMIM^＋-Cu2Cl3^- pairs. Full optimiza...The density functional theory （DFT） has been employed to investigate the electronic structures ofEMIM^＋（1-ethyl-3-methylimidazolium＋）, CuCl2^-, Cu2Cl3^- and EMIM^＋-CuCl2^-, EMIM^＋-Cu2Cl3^- pairs. Full optimization and frequency analyses of EMIM^＋, CuCl2^-, Cu2Cl3^-, eight initial EMIM^＋-CuCl2^-, and six initial EMIM^＋-Cu2Cl3^- geometries have been carried out using Gaussian-94 software-package at 6-3 I＋G （d, p） basis set level for hydrogen, carbon, nitrogen, chlorine atoms and the Hay-Wadt effective core potential for copper atoms. The electronic structures of the lowest energy of EMIM^＋-CuCl2^-, EMIM^＋-Cu2Cl3^- pairs, single EMIM^＋, CuCl2^-, and Cu2Cl3^- have been comparatively studied. The calculated results showed that the optimized EMIM^＋-CuCl2^- pair conformer of the lowest energy was five ring moiety parallel to CuCl2^- plane with a distance of around 3.5,A, while EMIM^＋-Cu2Cl3^- pair conformer of the lowest energy was five ring moiety of EMIM^＋ perpendicular to Cu2Cl3^- plane with a distance of around 3.0 ,A between terminal chlorine atoms and 5-ring plane of EMIM^＋. The cohesion between cation and anion is electrostatic interaction and C-H---Cl hydrogen bonds are reinforced by charge assistance. The frequency analyses suggested that all stationary points are minimum points because of absence of imaginary frequency. The low energy of interaction caused by bulky asymmetry of EMIM^＋, and charge dispersion of cation and anion give rise to low melting point of ionic liquids EMIM^＋-CuCl2^-, and EMIM^＋-Cu2Cl3^- . The interaction energy caused by the distance between cations and anions was investigated by single point energy scan.展开更多
In this paper, the effect of ionic liquids on the CaCO3 crystal growth has been studied for the first time. The obtained CaCO3 crystals were charactered by the X-ray diffraction and scanning electron micrographs. The ...In this paper, the effect of ionic liquids on the CaCO3 crystal growth has been studied for the first time. The obtained CaCO3 crystals were charactered by the X-ray diffraction and scanning electron micrographs. The results showed that the control ability of ionic liquids for CaCO3 crystals growth was dependent on the counter anion very much.展开更多
A 1-butyl-3-methylimidazolium chloride-salt aqueous two-phase system was studied on extraction of abused drugs. The effects of sorts of salts, temperature, concentration of salt and drugs on system were investigated s...A 1-butyl-3-methylimidazolium chloride-salt aqueous two-phase system was studied on extraction of abused drugs. The effects of sorts of salts, temperature, concentration of salt and drugs on system were investigated systematically. A satisfactory extraction efficiency of 93% was obtained for papaverine while that of morphine was 65%. The extraction mechanism was primarily discussed.展开更多
A single-drop liquid phase micro-extraction procedure using 1-butyl-3-methylimidazolium hexafluorophosphate （[C4MIM][PF6]） was demonstrated for the sensitive determination of four phenols in water samples. Under the...A single-drop liquid phase micro-extraction procedure using 1-butyl-3-methylimidazolium hexafluorophosphate （[C4MIM][PF6]） was demonstrated for the sensitive determination of four phenols in water samples. Under the optimized conditions, the linear range of proposed method was excellent in the range of 0.5-100 μg·L^-1, the reproducibility （RSD, n=6） were in the range 5.4%-8.9% and detection limits （S/N=3） were 0.3, 0.3, 0.5 and 0.5 μg·L^-1 for 2, 4-dichlorophenol, 2-naphthol, 2-nitrophenol and 4-chlorophenol, respectively. The experimental results indicated that the effect of complex matrices natural water samples could be resolved with addition of sodium ethylene diamine tetracetate （EDTA） into the samples. Excellent spiked recoveries were achieved for these four phenols ranged from 86.2%-114.9 %. All these facts demonstrated that the proposed method with merits of low cost, simplicity and easy operating would be a competitive alternative procedure for the determination of such compounds at trace level.展开更多
The effects of N-methylimidazole cation [Cnmim] with different alkyl chain lengths, the types of cations and anions of ionic liquids and the reaction parameters on the catalytic activity and the selectivity for 4,4′-...The effects of N-methylimidazole cation [Cnmim] with different alkyl chain lengths, the types of cations and anions of ionic liquids and the reaction parameters on the catalytic activity and the selectivity for 4,4′-bisphenol F were investigated. The hydrogen bonding between the hydroxyl of phenol and the C2-position hydrogen of imidazole moiety in hydrophilic imidazole-based ionic liquid has important influence on the selectivity for 4,4′-bisphenol F, and under the conditions of the molar ratio of phenol/[C4mim][HSO4] 1:1, reaction temperature65 °C and the theoretical molar ratio of phenol/formaldehyde 2:1, the selectivity for 4,4′-bisphenol F reached69.1%. Compared with the high phenol/formaldehyde ratio reported in literatures, the low molar ratio of phenol/formaldehyde and the low reaction temperature can greatly reduce energy consumption, and has important significance for industrial application.展开更多
A new transition metal complex, [Cu（N-MeIm）4（BF4）2]（N-MeIm=N-methylated imidazoles, BF4= tetrafluoroborate）, was synthesized via the solvothermal method in ionic liquid. The ionic liquid acts as thermal decompos...A new transition metal complex, [Cu（N-MeIm）4（BF4）2]（N-MeIm=N-methylated imidazoles, BF4= tetrafluoroborate）, was synthesized via the solvothermal method in ionic liquid. The ionic liquid acts as thermal decomposition reaction medium, soft temple agent and ligand compound. The central Cu（Ⅱ） ion is coordinated by four N atoms from four N-methylated imidazole ligands, and the four N-methylated imidazole rings are perpendicular to each other. The crystal structure of [Cu（N-MeIm）4（BF4）2] was determined by single crystal X-ray diffraction. The results of thermogravimetry（TG） and Fourier transform infrared spectrometry（FTIR） analyses were in accordance with that of crystal structure. The complex showed strong ligand-based absorbance with maximum wavelength at 208 and 231 nm, which are attributed to π-π＊ transition of the N-methylated imidazole ligands.展开更多
基金Project(50574031) supported by the National Natural Science Foundation of China
文摘1-butyl-3-methylimidazolium perchlorate([BMIM]ClO4) was synthesized by two steps with N-methylimidazolium.Some physico-chemical properties,such as density,surface tension,viscosity,electrical conductivity as well as electrochemical window,were investigated and solvent performance was also studied.The results show that this kind of ionic liquid is an excellent electrolyte with low viscosity,high electrical conductivity and wide electrochemical window.In addition,[BMIM]ClO4 is soluble in most conventional solvents and some metal oxides have high solubility in it,which lays the foundation of direct electrolysis of metal oxides in this ionic liquid.
基金Natural Science Foundation of Shanghai,China(No.09ZR1401500)
文摘Poly[ 2, 2-（m.phenylene） -5, 5-bibenzimidazole] （mPBI） were synthesized by mixing 3, 3＇, 4, 4＇-tetraaminobiphenyl and isophthallc acid in 1 -butyl-3 -methyUmidazolinm chloride （ E BMIM] CI）. Intrinsic viscosity of mPBI polymers was 0.67 dL/g which was measured in 96% sulfuric acid. The polymer was characterized by Fourier transform infrared spectroscopy （FTIR）, nuclear magnetic resonance （ 1H-NMR ）, and thermogravimetric analysis （TGA）. The effects of polymerization conditions on the intrinsic viscosity of mPBI were investigated. It showed that the molecular weight of polymer mainly depended on pre-reaction time and reaction temperature. Comparison of structure and properties of mPBI synthesized in ionic liquids（ILs） and polyphosphoric acid was also reported. It indicates that the ionic liquids are a kind of good solvents in synthesis process of m_PBI and ionic liquids mainly affect molecular weight of mPBL
基金This work was supported by the National Natural Science Key Foundation of China (20490209) and Young Teacher Foundation of Beijing Chemical Technology University (QN0308)
文摘The geometries of reactant, product and transition state of the title reaction have been optimized by using density functional theory (DFT) at the B3LYP/6-31G(d,p) and B3LYP/6- 311++G(d,p) levels. The variations of the bond parameters in the course of reaction were analyzed. The zero point energy corrections were performed by vibrational analysis. The equilibrium states and the transition state were verified according to the number of virtue frequency of geometry. The intrinsic reaction coordinates (IRC) were calculated from the transition state. The calculated results show that the double bond rearrangement of butene catalyzed by 1-butyl-3-methyl-imidazolium cation is a one-step reaction. The forward energy barrier of isomerization from 1-butene to 2- butene is about 193 kJ·mol-1 and the reverse energy barrier about 209 kJ·mol-1 at the B3LYP/6- 31G(d,p) level, which means that the reaction is easy to proceed at or above room temperature.
文摘The density functional theory （DFT） has been employed to investigate the electronic structures ofEMIM^＋（1-ethyl-3-methylimidazolium＋）, CuCl2^-, Cu2Cl3^- and EMIM^＋-CuCl2^-, EMIM^＋-Cu2Cl3^- pairs. Full optimization and frequency analyses of EMIM^＋, CuCl2^-, Cu2Cl3^-, eight initial EMIM^＋-CuCl2^-, and six initial EMIM^＋-Cu2Cl3^- geometries have been carried out using Gaussian-94 software-package at 6-3 I＋G （d, p） basis set level for hydrogen, carbon, nitrogen, chlorine atoms and the Hay-Wadt effective core potential for copper atoms. The electronic structures of the lowest energy of EMIM^＋-CuCl2^-, EMIM^＋-Cu2Cl3^- pairs, single EMIM^＋, CuCl2^-, and Cu2Cl3^- have been comparatively studied. The calculated results showed that the optimized EMIM^＋-CuCl2^- pair conformer of the lowest energy was five ring moiety parallel to CuCl2^- plane with a distance of around 3.5,A, while EMIM^＋-Cu2Cl3^- pair conformer of the lowest energy was five ring moiety of EMIM^＋ perpendicular to Cu2Cl3^- plane with a distance of around 3.0 ,A between terminal chlorine atoms and 5-ring plane of EMIM^＋. The cohesion between cation and anion is electrostatic interaction and C-H---Cl hydrogen bonds are reinforced by charge assistance. The frequency analyses suggested that all stationary points are minimum points because of absence of imaginary frequency. The low energy of interaction caused by bulky asymmetry of EMIM^＋, and charge dispersion of cation and anion give rise to low melting point of ionic liquids EMIM^＋-CuCl2^-, and EMIM^＋-Cu2Cl3^- . The interaction energy caused by the distance between cations and anions was investigated by single point energy scan.
文摘In this paper, the effect of ionic liquids on the CaCO3 crystal growth has been studied for the first time. The obtained CaCO3 crystals were charactered by the X-ray diffraction and scanning electron micrographs. The results showed that the control ability of ionic liquids for CaCO3 crystals growth was dependent on the counter anion very much.
基金This study was jointly supported by the National Natural Science Foundation of China(20275003 and 20335010).
文摘A 1-butyl-3-methylimidazolium chloride-salt aqueous two-phase system was studied on extraction of abused drugs. The effects of sorts of salts, temperature, concentration of salt and drugs on system were investigated systematically. A satisfactory extraction efficiency of 93% was obtained for papaverine while that of morphine was 65%. The extraction mechanism was primarily discussed.
文摘A single-drop liquid phase micro-extraction procedure using 1-butyl-3-methylimidazolium hexafluorophosphate （[C4MIM][PF6]） was demonstrated for the sensitive determination of four phenols in water samples. Under the optimized conditions, the linear range of proposed method was excellent in the range of 0.5-100 μg·L^-1, the reproducibility （RSD, n=6） were in the range 5.4%-8.9% and detection limits （S/N=3） were 0.3, 0.3, 0.5 and 0.5 μg·L^-1 for 2, 4-dichlorophenol, 2-naphthol, 2-nitrophenol and 4-chlorophenol, respectively. The experimental results indicated that the effect of complex matrices natural water samples could be resolved with addition of sodium ethylene diamine tetracetate （EDTA） into the samples. Excellent spiked recoveries were achieved for these four phenols ranged from 86.2%-114.9 %. All these facts demonstrated that the proposed method with merits of low cost, simplicity and easy operating would be a competitive alternative procedure for the determination of such compounds at trace level.
基金Supported by the National Natural Science Foundation of China(21276217)
文摘The effects of N-methylimidazole cation [Cnmim] with different alkyl chain lengths, the types of cations and anions of ionic liquids and the reaction parameters on the catalytic activity and the selectivity for 4,4′-bisphenol F were investigated. The hydrogen bonding between the hydroxyl of phenol and the C2-position hydrogen of imidazole moiety in hydrophilic imidazole-based ionic liquid has important influence on the selectivity for 4,4′-bisphenol F, and under the conditions of the molar ratio of phenol/[C4mim][HSO4] 1:1, reaction temperature65 °C and the theoretical molar ratio of phenol/formaldehyde 2:1, the selectivity for 4,4′-bisphenol F reached69.1%. Compared with the high phenol/formaldehyde ratio reported in literatures, the low molar ratio of phenol/formaldehyde and the low reaction temperature can greatly reduce energy consumption, and has important significance for industrial application.
基金Supported by the National Natural Science Foundation of China（Nos. 51104050, 51301050, 51202047）, the Natural Science Foundation of Heilongjiang Province, China（No. E201413）, the Technology Foundation for Selected Overseas Chinese Scholar of Heilongjiang Province, China（No. 159150130002）, the Postdoctoral Scientific Research Developmental Fund of Heilongjiang Province, China（No.LBH-3236310448） and the Fundamental Research Funds for the Central Universities, China（No. GK2150260120）.
文摘A new transition metal complex, [Cu（N-MeIm）4（BF4）2]（N-MeIm=N-methylated imidazoles, BF4= tetrafluoroborate）, was synthesized via the solvothermal method in ionic liquid. The ionic liquid acts as thermal decomposition reaction medium, soft temple agent and ligand compound. The central Cu（Ⅱ） ion is coordinated by four N atoms from four N-methylated imidazole ligands, and the four N-methylated imidazole rings are perpendicular to each other. The crystal structure of [Cu（N-MeIm）4（BF4）2] was determined by single crystal X-ray diffraction. The results of thermogravimetry（TG） and Fourier transform infrared spectrometry（FTIR） analyses were in accordance with that of crystal structure. The complex showed strong ligand-based absorbance with maximum wavelength at 208 and 231 nm, which are attributed to π-π＊ transition of the N-methylated imidazole ligands.
