Pyridinium ionic liquids（ILs, 1-ethyl acetate pyridinium hexfluorophosphate [EAPy][PF6] and 1-ethyl acetate-3-methyl pyridinium hexfluorophosphate [EAMPy][PF6]）, were synthesized by a two-step process involving intr...Pyridinium ionic liquids（ILs, 1-ethyl acetate pyridinium hexfluorophosphate [EAPy][PF6] and 1-ethyl acetate-3-methyl pyridinium hexfluorophosphate [EAMPy][PF6]）, were synthesized by a two-step process involving introduction of one ethyl acetate group and anion metathesis. Colorless single crystals of the two ILs were initially obtained using the solvent-evaporation method in mixed solvents. Single-crystal X-ray diffraction was used to deter- mine the crystal structures. [EAPy][PF6] crystallizes in the monoclinic space group C2/c with a-2.2748（16） nm, b=0.6204（4） nm, c=1.8552（12） nm and Z-8, whereas [EAMPy][PF6] crystallizes in the orthorhombic space group P212121 with a=0.7126（17） nm, b=1.2792（3） nm, c=1.5327（3） nm and Z-4. The structure of [EAPy][PF6] contains double zigzag chains formed by alternately pairing large organic cations with the octahedral anions of [P1F6]- or [P2F6] . The [P1F6] and [P2F6]- anions occupy respectively two distinct crystallographic sites in crystal packing models. The structure of [EAMPy][PF6] includes ladder-type chains constructed through pairing pyridinium cations with inorganic anions of [PF6]-. The [PF6]- anion in [EAMPy][PF6] shows a distorted octahedron structure and is sandwiched by ethyl acetate groups in crystallographic stacking. This study reveals the influence of chemical modification involving the methyl group（CH3） onto crystallographic structure of pyridinium ILs. Thermal analysis indicates that the difficult crystallization of the two 1Ls is related to the low void filling of ion pairs in crystal structure, leading to relatively low melting point and evident supercooling during the cooling process. Additionally, the experimental results indicate that the two ILs have electrochemical activity. The ethyl acetate group also allows downward shifting of electrochemical windows to less negative positions and the ionic conductivities of the two ILs follow an Arrhenius-type behavior.展开更多
In this paper, CuO, CuO/Cu2O, Cu2O, Cu2O/Cu and Cu microcrystals were synthesized via a hydrothermal method by mixing Cu（NO3）2·3H2O and NaOH together in the presence of an ionic liquid l-butyl-3-methylimidazoli...In this paper, CuO, CuO/Cu2O, Cu2O, Cu2O/Cu and Cu microcrystals were synthesized via a hydrothermal method by mixing Cu（NO3）2·3H2O and NaOH together in the presence of an ionic liquid l-butyl-3-methylimidazolium tetrafluoroborate（[BMIM]BF4） or 1-butyl-3-methylimidazolium chloride（[BMIM]Cl）. The structures and the morphologies of the obtained products were characterized by means of X-ray diffractometer（XRD）, field-emission scanning electron microscopy/energy-dispersive spectroscopy（FESEM/EDS）, transmission electron microscopy/selected area electron diffraction（TEM/SAED） and Raman spectroscopy. The result of XRD indicates that Cu2O and Cu microcrystals are cubic phase and the Raman spectra confirm the presence of carbon. The results of FESEM and TEM images show Cu2O microcrystals as rule cubes of 2μm in length and Cu particles of 5 μm in diameter. According to the difference between crystal structures, bi-eomponent and single component products were synthesized by adjusting the reaction conditions. A possible formation mechanism of Cu2O and Cu was proposed in [BMIM]BF4.展开更多
Ionic liquid 1-hexadecyl-3-methylimidazolium bromide [C16mim]Br was synthesized by solvent-free alkylation of N-methylimidzole with hexadecyl bromide. A large transparent single crystal of 1-hexadecyl-3-methylimidazol...Ionic liquid 1-hexadecyl-3-methylimidazolium bromide [C16mim]Br was synthesized by solvent-free alkylation of N-methylimidzole with hexadecyl bromide. A large transparent single crystal of 1-hexadecyl-3-methylimidazolium bromide monohydrate （[C16mim]Br·H2O）, 4 mm in length, was firstly obtained in the water-trichloromethane-toluene growth system （Vwater＇Vtrichloromethane＇Vtoluene = 0.1：1：2）. The crystal structure was determined by single-crystal X-ray diffraction method. It crystallizes in the triclinic system, space group P1, with a = 5.4962（15）, b = 7.839（2）, c = 27.279（8） A, α = 94.375, β = 91.500, γ = 101.999°, Z = 2, V = 1145.2（5） A3, C20H41BrN2O, Mr = 405.46, Dc = 1.176 Mg/m3, μ = 1.804 mm^-1, F（000） = 436, the final R = 0.0523 and wR = 0.1345. The 3D supramolecular structure is constructed through weak interactions between imidazolium cations, Br- anions and lattice water molecules. The long alkyl chain to the imidazolium ring and lattice water molecules play an important role in the self-assembly process. Moreover, it is proposed that [C16mim]Br in water has aggregation behavior and the possible self-assembled structure is the interdigitated pattern. Finally, thermal stability of [C16mim][Br]·H2O was also studied by DSC and TGA analysis.展开更多
Novel bent shape tenary facial amphiphilic imidazolium ILC which consist of a ^-conjugated bent aromatic cores （2,5-dithiophenylethynyl phenyl bent core）, two terminal poliphilic alkyl chains and lateral n-alky chai...Novel bent shape tenary facial amphiphilic imidazolium ILC which consist of a ^-conjugated bent aromatic cores （2,5-dithiophenylethynyl phenyl bent core）, two terminal poliphilic alkyl chains and lateral n-alky chain terminated by an imidazolium bromide unit were synthesized by using Kumada and Sonogashira coupling reactions as key steps and both their thermotropic and lyotropic mesophase behaviors were studied by POM, DSC and XRD. Columnar phases were found in these compounds, a hexagonal cylinder model with core shell structure is supposed for the columnar phase formed by compound 1/8. Our study may provide a new strategy for designing new LC functional material.展开更多
基金Supported by the Natural Science Foundation of Shaanxi Province, China（No.2013JQ6010） and the Special Research Plan of Shaanxi Provincial Department of Education for Young Talents, China（No. 12JK0457）.
文摘Pyridinium ionic liquids（ILs, 1-ethyl acetate pyridinium hexfluorophosphate [EAPy][PF6] and 1-ethyl acetate-3-methyl pyridinium hexfluorophosphate [EAMPy][PF6]）, were synthesized by a two-step process involving introduction of one ethyl acetate group and anion metathesis. Colorless single crystals of the two ILs were initially obtained using the solvent-evaporation method in mixed solvents. Single-crystal X-ray diffraction was used to deter- mine the crystal structures. [EAPy][PF6] crystallizes in the monoclinic space group C2/c with a-2.2748（16） nm, b=0.6204（4） nm, c=1.8552（12） nm and Z-8, whereas [EAMPy][PF6] crystallizes in the orthorhombic space group P212121 with a=0.7126（17） nm, b=1.2792（3） nm, c=1.5327（3） nm and Z-4. The structure of [EAPy][PF6] contains double zigzag chains formed by alternately pairing large organic cations with the octahedral anions of [P1F6]- or [P2F6] . The [P1F6] and [P2F6]- anions occupy respectively two distinct crystallographic sites in crystal packing models. The structure of [EAMPy][PF6] includes ladder-type chains constructed through pairing pyridinium cations with inorganic anions of [PF6]-. The [PF6]- anion in [EAMPy][PF6] shows a distorted octahedron structure and is sandwiched by ethyl acetate groups in crystallographic stacking. This study reveals the influence of chemical modification involving the methyl group（CH3） onto crystallographic structure of pyridinium ILs. Thermal analysis indicates that the difficult crystallization of the two 1Ls is related to the low void filling of ion pairs in crystal structure, leading to relatively low melting point and evident supercooling during the cooling process. Additionally, the experimental results indicate that the two ILs have electrochemical activity. The ethyl acetate group also allows downward shifting of electrochemical windows to less negative positions and the ionic conductivities of the two ILs follow an Arrhenius-type behavior.
基金Research supported by Foundation of"Surpassing Project"of Jiangsu Province(QL9801)and Natural Science Founda-tion of Xuzhou Normal University(05XLB08)
基金Supported by the National Natural Science Foundation of China（Nos.51104050, 51301050, 51202047）, the Natural Science Foundation of Heilongjiang Province, China（Nos.E201413, E201419）, the Technology Foundation for Selected Overseas Chinese Scholar of Heilongjiang Province, China（No. 159150130002） and the Fundamental Research Funds for the Central Universities of China（No.HEUCF161501）.
文摘In this paper, CuO, CuO/Cu2O, Cu2O, Cu2O/Cu and Cu microcrystals were synthesized via a hydrothermal method by mixing Cu（NO3）2·3H2O and NaOH together in the presence of an ionic liquid l-butyl-3-methylimidazolium tetrafluoroborate（[BMIM]BF4） or 1-butyl-3-methylimidazolium chloride（[BMIM]Cl）. The structures and the morphologies of the obtained products were characterized by means of X-ray diffractometer（XRD）, field-emission scanning electron microscopy/energy-dispersive spectroscopy（FESEM/EDS）, transmission electron microscopy/selected area electron diffraction（TEM/SAED） and Raman spectroscopy. The result of XRD indicates that Cu2O and Cu microcrystals are cubic phase and the Raman spectra confirm the presence of carbon. The results of FESEM and TEM images show Cu2O microcrystals as rule cubes of 2μm in length and Cu particles of 5 μm in diameter. According to the difference between crystal structures, bi-eomponent and single component products were synthesized by adjusting the reaction conditions. A possible formation mechanism of Cu2O and Cu was proposed in [BMIM]BF4.
基金Supported by the Natural Science Basic Research Plan in Shaanxi Province (No.2007K071)
文摘Ionic liquid 1-hexadecyl-3-methylimidazolium bromide [C16mim]Br was synthesized by solvent-free alkylation of N-methylimidzole with hexadecyl bromide. A large transparent single crystal of 1-hexadecyl-3-methylimidazolium bromide monohydrate （[C16mim]Br·H2O）, 4 mm in length, was firstly obtained in the water-trichloromethane-toluene growth system （Vwater＇Vtrichloromethane＇Vtoluene = 0.1：1：2）. The crystal structure was determined by single-crystal X-ray diffraction method. It crystallizes in the triclinic system, space group P1, with a = 5.4962（15）, b = 7.839（2）, c = 27.279（8） A, α = 94.375, β = 91.500, γ = 101.999°, Z = 2, V = 1145.2（5） A3, C20H41BrN2O, Mr = 405.46, Dc = 1.176 Mg/m3, μ = 1.804 mm^-1, F（000） = 436, the final R = 0.0523 and wR = 0.1345. The 3D supramolecular structure is constructed through weak interactions between imidazolium cations, Br- anions and lattice water molecules. The long alkyl chain to the imidazolium ring and lattice water molecules play an important role in the self-assembly process. Moreover, it is proposed that [C16mim]Br in water has aggregation behavior and the possible self-assembled structure is the interdigitated pattern. Finally, thermal stability of [C16mim][Br]·H2O was also studied by DSC and TGA analysis.
基金the National Natural Science Foundation of China，the Yunnan Science Foundation
文摘Novel bent shape tenary facial amphiphilic imidazolium ILC which consist of a ^-conjugated bent aromatic cores （2,5-dithiophenylethynyl phenyl bent core）, two terminal poliphilic alkyl chains and lateral n-alky chain terminated by an imidazolium bromide unit were synthesized by using Kumada and Sonogashira coupling reactions as key steps and both their thermotropic and lyotropic mesophase behaviors were studied by POM, DSC and XRD. Columnar phases were found in these compounds, a hexagonal cylinder model with core shell structure is supposed for the columnar phase formed by compound 1/8. Our study may provide a new strategy for designing new LC functional material.
