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Chinese Journal of Structural chemistry 2007年第11期26卷 1337-1340页

作者：魏亦军王凤武朱其永 department of chemistry Huainan Normal College

The title mononuclear Schiffbase nickel（Ⅱ） complex [Ni（CIIHI4Br2N20）2（H2O）2]·2NOa·2C2H3N was prepared and characterized by elemental analysis, IR spectrum, and singlecrystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/n with a = 15.534（2）, b = 7.647（1）, c = 16.435（2）A, β = 103.252（2）°, V = 1900.3（4）A3, Z = 2, Dc = 1.750 g/cm^3, Mr = 1000.99, 2（MoKa） = 0.71073A,μ= 4.776 mm^-1, F（000） = 996, the fmal R = 0.0368 and wR = 0.0724. A total of 3988 unique reflections were collected, of which 2764 with Ⅰ 〉 2σ（Ⅰ） were observed. The complex consists of a mononuclear [Ni（Cl IHlaBr2N2O）2（H2O）2]2＋ cation, two nitrate anions and two acetonitrile molecules. The Ni atom, lying on the inversion centre, is sixcoordinated by two Schiff bases and two water molecules to assume an octahedral coordination geometry. The molecules in the crystal are linked through intermolecular hydrogen bonds of N-H…O, N-H…Br, O--H…O, O-H…N and C-H…O to form layers.

关键词： Schiff base nickel complex crystal structure hydrogen bonds

Synthesis and Crystal Structure of Bis{2-bromo-4-chloro-6-[(2-isopropylammonioethylimino)-methyl]phenolato}bisthiocyanatozinc(Ⅱ)

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Chinese Journal of Structural chemistry 2007年第11期26卷 1327-1331页

作者：王凤武魏亦军朱其永 department of chemistry Huainan Normal College

A Schiff base zinc（Ⅱ） complex [Zn（C12H16BrCIN2O）2（NCS）2] was prepared and characterized by elemental analysis, IR and single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 8.414（1）, b = 9.124（1）, c = 22.212（3） A, α= 79.177（2）, β = 86.296（2）, γ = 89.899（2）°, V= 1671.3（4） A3, Z = 2, Dc = 1.631 g/cm^3, Mr = 820.79, λ（MoKα） = 0.71073 A,μ= 3.444 mm^-1, F（000） = 824, R = 0.0646 and wR = 0.1179. A total of 7371 unique reflections were collected, of which 3904 with I 〉 2σ（Ⅰ） were observed. The complex crystallizes with two half-molecules per asymmetric unit and each mononuclear molecule is centrosymmetric. The Zn atom lying at the inversion centre is six-coordinated in a slightly distorted octahedral geometry by two phenolate O atoms and two inaine N atoms from two Schiffbase ligands, as well as two N atoms from two thiocyanate anions. In flae crystal structure, the combination of re-re stacking interactions and intermolecular hydrogen bonds （N-H…Br, N-H…O, N-H…N, C-H…O, C-H…S and C-H…CI） leads to a three-dimensional network.

关键词： Schiff base zinc complex crystal structure hydrogen bonds

Synthesis and Crystal Structure of 5(R)-(1R,2S,5R)-Menthoxy-4(R)-N-cyclohexylaminobutyrolactone

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Chinese Journal of Structural chemistry 2006年第12期25卷 1497-1501页

作者：郁兆莲李森兰陈庆华 department of chemistry Luoyang Normal College

The title compound, 5（R）-（1R,2S,5R）-menthoxy-4（R）-N-cyclohexylaminobutyrolactone 1, has been synthesized via the asymmetric Micheal addition reaction of 5（R）-menthoxy- 2（5H）-furanone 4 with cyclohexylamine 5, and structurally determined by single-crystal X-ray diffraction. Crystal data： C20H36NO3, Mr = 337.49, monoclinic system, space group P21, a = 9.8677（7）, b = 9.7737（7）, c=11.0204（8） A, β= 103.7820（10）°, V= 1032.25（13） A^3, Z = 2, Dc= 1.086 g/cm^3, 2（MoKα） = 0.071073 nm,μ= 0.071 mm^-1 and F（000） = 372. The structure was refined to R = 0.0328 and wR = 0.0864 for 4203 observed reflections （I 〉 2σ（I））. The crystallographic results of molecule 1 show that the functionalized N-cyclohexylamino group is linked in the 4-position of butyrolactone to form the novel chiral optically active compound.

关键词： chiral 4(R)-N-cyclohexylaminobutyrolactone optically active molecule X-raycrystailography

Synthesis and Crystal Structure of a Hydrogen-bonded Supramolecular Compound [(C_6H_5N_2O)_3·Cu_1._5]·6H_2O

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Chinese Journal of Structural chemistry 2006年第3期25卷 295-299页

作者：杜巧云辛凌云李云平曹佃省 department of chemistry Luoyang Normal College

A hydrogen-bonded supermolecular compound [（C6H5N2O）3·Cu1.5]·6H2O was synthesized from picolinamide and Cu（NO3）2·6H2O at the presence of sodium pyrophosphate decahydrate. It crystallizes in triclinic, space group P1^- with a = 1.05947（8）, b = 1.09130（8）, c = 1.11456（8） nm, a = 67.8460（10）, β= 84.497（1）, γ = 74.6210（10）°, C18H27Cu1.5N6O9, Mr = 566.77, V = 1.15077（15） nm^3, Z = 2, Dc = 1.636 g/cm^3, F（000） = 585,μ= 1.461 mm^-1, R1 = 0.0278 and wR2 = 0.0749. In the complex, the Cu（Ⅱ） ion reveals a distorted tetradentate plane-tetragonal geometry. The structure consists of neutral two-dimensional layers via hydrogen bonds O-H...O and N-H...O between the molecules, and the layers are connected by weak interactions of the Cu-Cu, Cu-N, π-π and hydrogen bonds to form a three-dimensional network structure.

关键词： picolinamide copper(Ⅱ) complex crystal structure supermolecule

Molecular Dynamics Studies of the Kinetics of Phase Changes in Clusters IV:Crystal Nucleation from Molten (NaCl)_(256) and (NaCl)_(500) Clusters

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Chinese Journal of chemistry 2003年第12期21卷 1543-1552页

作者：李小华黄锦凡 department of chemistry Nanjing Xiaozhuang College department of chemistry University of Michigan

Molecular dynamics computer simulation based on the Born-Mayer-Huggins potential function has been carried out to study the effects of cluster size and temperature on the nucleation rate of sodium chloride clusters in the temperature range of 580 K to 630 K. Clusters with 256 and 500 NaCl molecules have been studied and the results have been compared with those obtained from 108 molecule clusters. The melting point (MP) of the clusters were observed to increase with the size of the clusters and can be well described by a linear equation MP=1107(37)-1229(23)N -1/3 (N is the number of molecules in the cluster). The nucleation rate was found to decrease with increasing the cluster size or temperature. Various nucleation theories have been used to interpret the nucleation rates obtained from this molecular dynamics simulation. It is possible to use a constant diffuse interface thickness to interpret the nucleation rate from the diffuse interface theory in the temperature range of this study. However,the interfacial free energy estimated from classical nucleation theory and diffuse interface theory increases too fast with increasing the temperature while that from Gran-Gunton theory does not change with changing temperatures. The sizes of critical nuclei estimated from all the theories are smaller than those estimated from our simulations.

关键词： sodium chloride crystal nucleation rate interfacial free energy size dependence temperature dependence

SYNTHESIS AND CHARACTERIZATION OF TRIAZOLE CONTAINING LIQUID CRYSTALLINE POLYMERS THROUGH 1,3-DIPOLAR CYCLOADDITION POLYMERIZATION

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Chinese Journal of Polymer Science 2009年第6期27卷 761-770页

作者： Devamani Srividhya Sundaram Manjunathan Sivashankaran Nithyanandan Subramanan Balamurugan Sengodan Senthil department of chemistry Sona College of Technology department of chemistry Anna University

Liquid crystalline polymers containing 1,2,3-triazole units as linking groups have been synthesized from the monomers containing triad ester diazide and flexible dialkyne ester by 1,3-cycloaddition reaction and were characterized. Click reaction of azide and alkyne functionals catalyzed by Cu(I) yielded target polyesters with 1,2,3-triazole *** structure of the polymer was confirmed by spectral *** analysis reveals that the polymers have moderate molecular weight with narrow distribution.H...

关键词： Triazole Click chemistry Main chain polymers Azide-alkyne cycloaddition Liquid crystalline polymers

Hydrothermal Synthesis and Crystal Structure of a New Zero-dimensional Complex: [Zn(H_2BPTC)(phen)_2]_n·3nH_2O

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Chinese Journal of Structural chemistry 2007年第12期26卷 1495-1498页

作者：李秀梅董艳辉王庆伟崔运成刘博 department of chemistry Tonghua Teachers College department of Pharmacy and Food Science Tonghua Teachers College college of chemistry Jilin Normal University

A new metal-organic coordination complex [Zn（H2BPTC）（phen）2]n.3nH2O （BPTC = 3,3＇,4,4＇-benzophenone tetracarboxylate, phen = 1,10-phenanthroline） 1 has been obtained from hydrothermal reaction and characterized by elementaj analysis, IR, TG and single-crystal X-ray diffraction. In compound 1, the zinc cation is hexa-coordinated with two carboxylate oxygen atoms from one H2BPTC ligand and four nitrogen atoms from two different phen ligands, showing a slightly distorted octahedral geometry. Crystal data： C41H30N4O12Zn, Mr = 836.06, monoclinic, P21/c, a = 14.2714（9）, b = 16.9386（10）, c = 15.0151（9）A, β = 101.3420（10）^o, V= 3558.8（4）A3 Dc = 1.560 g/cm^3,μ（MoKa） = 0.766 mm^-1, F（000） = 1720, Z= 4, R = 0.0439 and wR = 0.1157 for 4123 observed reflections with I 〉 2 o（I）.

关键词： 3,3',4,4'-benzophenone tetracarboxylate crystal structure zinc(Ⅱ) complex

A mild and efficient method for the methoxymethylation and acetylation of alcohols promoted by benzyltriphenylphosphonium tribromide

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Chinese Chemical Letters 2010年第10期21卷 1187-1190页

作者： Farhad Shirini Gholam Hossein Imanzadeh Seyyed Ali Reza Mousazadeh Iraj Mohammadpoor-Baltork Masoumeh Abedin department of chemistry College of ScienceUniversity of Guilan department of chemistry College of ScienceUniversity of Mohaghegh-Ardabili department of chemistry College of ScienceIsfahan University

A mild and efficient method for the conversion of alcohols to their corresponding methoxymethyl ethers and acetates using benzyltriphenylphosphonium tribromide （BTPTB） as catalyst is described. All reactions were pe... 详细信息

关键词： Benzyltriphenylphosphonium tribromide Alcohols Methoxymethylation Acetylation Heterogeneous reaction conditions

A VERSATILE AND REGIOSELECTIVE SYNTHESIS OF VICINAL AZIDOALCOHOLS USING CROSS-LINKED POLY(4-VINYLPYRIDINE) SUPPORTED AZIDE ION UNDER SOLVENT-FREE CONDITIONS

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Chinese Journal of Polymer Science 2013年第12期31卷 1660-1669页

作者： Mohammad Ali Karimi Zarchi Ali Tarabsaz department of chemistry College of ScienceYazd University

A new polymeric reagent, cross-linked poly（4-vinylpyridine） supported azide ion, [P4-VP]N3, was introduced as polymeric reagents for efficient and regioselective conversion of epoxides to azidohydrins in the presence of cross-linked poly（4-vinylpyridine） supported sulfuric acid, [P4-VP]H2SO4, as a solid proton source and as catalyst under solvent-free conditions. The advantages of this polymeric reagent over some of those reported in the literature are easy work-up procedure and regeneration of the reagent.

关键词： Ring opening of epoxide fl-Azidoalcohols Poly(4-vinytpyridine) Solvent-free conditions Regioselectivity.

CO2-mediated bicarbonate conversion to concentrated formate in a CEM-based electrolyzer

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Journal of Energy chemistry 2025年第1期 605-611页

作者： Haocheng Xiong Donghuan Wu Haonan Li Andrew Li Qikun Hu Siyao Song Bingjun Xu Qi Lu State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University college of chemistry and Molecular Engineering Peking University Ordos Laboratory

Renewable energy-driven bicarbonate conversion to valuable chemicals presents an attractive strategy for mitigating CO2emissions,as bicarbonate can be efficiently generated from the capture of atmospheric CO2using alkaline solutions with reactive *** this work,we present a CO2-mediated bicarbonate conversion to pure formate using a cation exchange membrane-based electrolyzer with a 25 cm2electrode *** electrolysis achieved selectivities exceeding 75%for formate at a total current of 2.5 A,achieving formate concentrations up to 1.2 M and yields as high as 95%over extended *** techno-economic assessment confirmed the economic viability of the process,highlighting the potential for bicarbonate electrolysis as a sustainable method for producing valuable chemicals.

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