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A highly efficient and facile procedure for the one‐pot three‐component synthesis of 3,4‐dihydropyrimidin‐2‐(1H )ones/thiones from the one‐pot condensation of aldehyde, β‐dicarbonyl compound and urea/thiourea was developed. The methodology is applicable to a wide range of substrates with high yield in the presence of (C5H6N4O)(C5H5N4O)3(C5H4N4O)[Bi2Cl11]Cl2. The complex is an air‐stable, environmentally friendly and recoverable catalyst and can efficiently catalyze the Biginelli reaction. The catalyst has high catalytic efficiency with low catalyst loading, and can be recycled ten times with only a small loss of activity.  相似文献   

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The reaction of VO(acac)2 with 2-hydroxyl-1-naphthaldehyde isonicotinyl hydrazone and amines (ethylenediamine or diethylenetriamine) in CH3OH yields crystals of novel vanadium compounds characterized by IR, NMR spectroscopic methods and X-ray single-crystal structure determination. Two different vanadium units exist in the crystal cell of [VO2(C17H11N3O2)][VO- (C4H13N3)(C6H5N3O)](C2H5OH) which crystallizes in the triclinic system, space group P1 with a = 8.0104(17), b = 13.898(3), c = 14.955(3)A, α = 89.103(4), β = 79.551(4), γ = 78.352(4)°, V = 1603.3(6)A^3, Mr = 723.54, Dc = 1.499 g/cm^3, Z = 2, λ(MoKα) = 0.71073 ]A,μ= 0.644 mm^-1, F(000) = 748, the final R = 0.0547 and wR = 0.0997 for 8920 observed reflections with I 〉 2σ(I). According to structure analysis, two different molecules are arranged in the lattice and the two vanadium atoms adopt octahedral and square pyramidal coordination geometries, respectively. The interactions between DNA and vanadium complexes have been investigated by UV-Vis absorption spectro- photometry.  相似文献   

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Ag(Ⅰ)配合物的几何构型多变,最常见的是配位数为2的线性构型和配位数为4的四面体构型。前者如Ag(NH_3)_2~+及Ag(CN)_2,后者如[Ag(SC(CH_3)NH_2)_4]Cl、[(Ph_3)Ag(Cl)]和[(Ph_3MeP)_3Ag(BH_4]等。配位数为4的平面四方构型却罕见,只在当有一定刚性的四氮杂环十四烷和Ag(Ⅰ)生成配合物时才是平面四方构型。 本文报道一种新型异三核含银配合物的合成及其晶体结构,其中Ag是平面四方构型。  相似文献   

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合成了4个新型的稀土化合物(C26H40N2O4)[Ln(NO3)5H2O](Ln=Pr,Nd,Sm,Eu),采用元素分析和红外光谱表征,用四圆衍射仪测定了其中(C26H40N2O4)[Eu(NO3)5H2O]的晶体结构,属三斜晶系,P1空间群,晶胞参数:α=0.9100(4)nm,b=1.3560(3)nm,c=1.6463(4)nm;α=68.62(2)°,β=74.84(3)°,γ=87.50(2)°;Z=2.中心铕离子由5个硝酸根的10个氧原子和1个水分子中的氧原子配位,配位数是11.1,7,10,16-四氧-4,13-二氮杂-N,N'-二苄基环十八烷(N,N'-二苄基穴醚(2,2))未参与配位.  相似文献   

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The scandium(III) cations in the structures of pentaaqua(biuret‐κ2O,O′)scandium(III) trichloride monohydrate, [Sc(C2H5N3O2)(H2O)5]Cl3·H2O, (I), and tetrakis(biuret‐κ2O,O′)scandium(III) trinitrate, [Sc(C2H5N3O2)4](NO3)3, (II), are found to adopt very different coordinations with the same biuret ligand. The roles of hydrogen bonding and the counter‐ion in the establishment of the structures are described. In (I), the Sc3+ cation adopts a fairly regular pentagonal bipyramidal coordination geometry arising from one O,O′‐bidentate biuret molecule and five water molecules. A dense network of N—H...Cl, O—H...O and O—H...Cl hydrogen bonds help to establish the packing, resulting in dimeric associations of two cations and two water molecules. In (II), the Sc3+ cation (site symmetry 2) adopts a slightly squashed square‐antiprismatic geometry arising from four O,O′‐bidentate biuret molecules. A network of N—H...O hydrogen bonds help to establish the packing, which features [010] chains of cations. One of the nitrate ions is disordered about an inversion centre. Both structures form three‐dimensional hydrogen‐bond networks.  相似文献   

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The novel copper(Ⅱ) complex with 2-oxo-propionic acid benzoyl hydrazone and pyridine ligands, Cu(C10H8N2O3)·(C5H5N)·(H2O) (C10H8N2O32- is the dinegative ion of 2-oxo-propionicacid benzoyl hydrazone), has been synthesized and characterized by elemental analysis and IR. The crystal structure of the title complex was determined by single crystal X-ray diffraction technique. Complex crystallized in the triclinic space group P1 with a = 0.729 08(10) nm, b= 1.020 01(14) nm, c= 1.126 28(15) nm, α = 71.644(2) °, β = 80.437(2) °, γ = 89.160(2)°, V= 0.78328(18) nm3, Z= 2, Dc= 1.547 Mg·m-3, μ(Mo) = 1.417 mm-1, F(000) = 374. The final R1 = 0.030 6, wR2= 0.084 2 for 2 992 observed reflections [I≥2σ(I)] out of 3357 unique reflections. In this complex, copper(Ⅱ) ion is square-pyramidally coordinated by two oxygen atoms and one nitrogen atom of tridentate C10H8N2O32- ligand, one nitrogen atom of the pyridine ligand, and one oxygen atom of water molecule with the oxygen atom of water molecule locating at the apical position. The analysis of the crystal structure indicates that the complex has a one-dimensional chain structure, which is formed by intermolecular hydrogen bonds. CCDC: 222656.  相似文献   

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Xiaoyan You  Lixia Zhu  Jia Sun 《中国化学》2010,28(11):2174-2178
A novel organically templated copper pentaborate, [Cu(C3N2H4)4][Cu(CH3COO)2(C3N2H4)2(H2O)2]‐ [B5O6(OH)4]2, was synthesized by hydrothermal reaction and characterized by elemental analysis, single‐crystal X‐ray diffraction, FT‐IR spectroscopy, Raman spectroscopy and TGA. The crystal structure of this compound consists of two copper‐centered polyhedra and two discrete [B5O6(OH)4]? pentaborate anions, which are linked together through intensive hydrogen bonding interactions, forming a 3D framework with large channels along c axis. The discrete pentaborate anions form infinite layers by hydrogen bonds. Moreover, the two crystallographically different octahedral coppers are connected by common oxygen atom to form an infinite chain.  相似文献   

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Recent work in the preparation of organically templated metal sulfates under hydrothermal conditions has been extended to include the sulfation of alpha-molybdena through the synthesis of [C(5)H(14)N(2)][(MoO(3))(3)(SO(4))].H(2)O. Single crystals were grown under hydrothermal conditions from molybdenum oxide, water, sulfuric acid, and an enantiomerically pure (R)-2-methylpiperazine source and characterized using both single-crystal X-ray diffraction and infrared spectroscopy. One-dimensional [(MoO(3))(3)(SO(4))](n)(2n-) chains, based on a neutral alpha-molybdena backbone, are connected through an extensive hydrogen-bonding network containing [C(5)H(14)N(2)](2+) cations and occluded water molecules. The direction of the hydrogen bonding is primarily dictated by the nucleophilicity of the respective oxide ligands, as determined using bond valence sums.  相似文献   

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合成了标题化合物。该化合物的分子式[Ni(C5H5N)2(C7H6O2N)2]H2O(C24H24N4NiO3),分子量475.18,采用单色的MoKα (λ = 0.71073 )射线测定,共收集7408个数据,其中独立衍射点2567个(Rint = 0.0272),I > 2s(I)可观测点数1926个,结果表明该化合物属单斜晶系, 空间群C2/c其晶胞参数为: a = 14.466(2),b = 12.193(2),c = 14.072(2) ;β = 116.229(2)°,V = 2226.6(5) 3,Z = 4,Dc = 1.418 g/cm3 ,μ = 0.905 mm-1,F(000) = 992. 2个水杨醛亚胺各提供2个配位原子参与配位,2个吡啶各提供1个配位原子参与配位,该配合物是六配位的八面体构型,同时讨论了该体系中不同配位原子的配位能力的差异。  相似文献   

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The single crystals of (C2H7N4O)2[UO2(C2O4)2(H2O)] were studied by X-ray diffraction. The crystals are monoclinic, space group Pn, Z = 2, unit cell parameters: a = 9.4123(2) Å, b = 8.4591(2) Å, c = 11.8740(3) Å, β = 105.500(10)°, V = 911.02(4) Å3. The main structural units of the crystals of I are islet complex groups [UO2(C2O4)2(H2O)]2? corresponding to the crystal chemical group AB 2 01 M1 (A = UO UO 2 2+ , B01 = C2O 4 2? , M = H2O) of uranyl complexes. Uranium-containing mononuclear complexes are connected into a three-dimensional framework through the electrostatic interactions and hydrogen bonding system involving carbamyolguanidinium ions.  相似文献   

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