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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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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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An X-ray diffraction study of the single crystals of (C2H7N4O)2[(UO2)2(OH)2(C2O4)(CHO2)2] was carried out. The compound crystallizes in the triclinic system, space group $P\bar 1$ , Z = 2, a = 5.5621(8) Å, b = 8.1489(10) Å, c = 11.8757(16) Å, α = 88.866(7)°, β = 82.204(6)°, γ = 87.378(6)°, V = 532.7(1) Å3, ρcalcd = 2.988 g/cm3. The main structural units in the crystal are the [(UO2)2(OH)2(C2O4)(CHO2)2)]2? chains corresponding to the crystal chemical group A2M 2 2 K02M 2 1 (A = UO 2 2+ , M2 = OH?, K02 = C2O 4 2? , M1 = CHO 2 ? ) of uranyl complexes. The chains are united into a three-dimensional framework through the electrostatic interaction and hydrogen bonds involving uranyl, oxalate, and hydroxyl groups, formate ions, and 1-carbamoylguanidinium cations.  相似文献   

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Synthetic methods for several novel phosphoramidate compounds containing the P(O)NHC(O) bifunctional group were developed. These compounds with the general formula R1C(O)NHP(O)(N(R2)(CH2C6H5))2, where R1 = CCl2H, p-ClC6H4, p-BrC6H4, o-FC6H4 and R2 = hydrogen, methyl, benzyl, were characterized by several spectroscopic methods and analytical techniques. The effects of phosphorus substituents on the rotation rate around the P–Namine bond were also investigated. 1H NMR study of the synthesized compounds demonstrated that the presence of bulky groups attached to the phosphorus center and electron withdrawing groups in the amide moiety lead to large chemical-shift non-equivalence (ΔδH) of diastereotopic methylene protons. The crystal structures of CCl2HC(O)NHP(O)(NCH3(CH2C6H5))2, p-ClC6H4C(O)NHP(O)(NCH3(CH2C6H5))2, CCl2HC(O)NHP(O)(N(CH2C6H5)2)2 and p-BrC6H4C(O)NHP(O)(N(CH2C6H5)2)2 were determined by X-ray crystallography using single crystals. The coordination around the phosphorus center in these compounds is best described as distorted tetrahedral and the P(O) and C(O) groups are anti with respect to each other. In the compound Br-C6H4C(O)NHP(O)(N(CH2C6H5)2)2 (with two independent molecules in the unit cell), two conformers are connected to each other via two different N–H?O hydrogen bonds forming a non-centrosymmetric dimer. In the crystalline lattice of other compounds, the molecules form centrosymmetric dimers via pairs of same N–H?O hydrogen bonds. The structure of CCl2HC(O)NHP(O)(N(CH2C6H5)2)2 reveals an unusual intramolecular interaction between the oxygen of CO group and amine nitrogen.  相似文献   

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Law GL  Wong KL  Zhou X  Wong WT  Tanner PA 《Inorganic chemistry》2005,44(12):4142-4144
New eight- and nine-coordinate luminescent europium(III) and terbium(III) complexes 1-4 with carbonyl group coordination have been prepared using the monodentate ligand (L) 2,4-diamino-6-hydroxy pyrimidine and characterized by X-ray and spectroscopic methods.  相似文献   

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The crystal structure of [Ni(C5H2N2O4)(2, 2?-bipy)(H2O)2]·2H2O 1 has been determined by X-ray diffraction. Crystal data: triclinic system, space group P ī with a = 7.9424(3), b = 9.9417(3), c = 12.1867(3) (A。), α = 84.771(1), β = 77.375(2), γ = 68.993(2)°, C15H18N4O8Ni, Mr = 440.7, V = 876.16(5) (A。)3, Z = 2, Dc = 1.672 g/cm3, F(000) = 456, ((MoK() = 1.162 mm-1, the final R = 0.0464 and wR = 0.1055 for 3026 observed reflections with I > 2((I). In the title compound, the nickel ion is coordinated by a nitrogen atom and an oxygen atom from the orotate ligand, two nitrogen atoms from 2, 2'-bipy and two oxygen atoms from the coordinated water molecules in a distorted octahedral geometry. The presence of intermolecular hydrogen bonding and (-( stacking interaction of aromatic rings from 2, 2'-bipy results in a 3D structure.  相似文献   

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IntroductionThesynthesisandsorptionpropertiesofopenframe worksolidssuchaszeolites1andmetalmolybdenumphos phate2 ,3withlargecavitiesprovokedenormousinterestbe causeoftheirpotentialapplicationincatalysis .One ,two andthree dimensionalsolidcompoundsconsistingo…  相似文献   

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