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1.
王毅  邵华  徐为人  王建武 《结构化学》2012,31(1):110-114
The title compound ethyl 1-(2-bromoethyl)-3-(4-methoxyphenyl)-1H-pyrazole-5-carboxylate 1 has been synthesized and structurally characterized by single-crystal X-ray diffraction.The crystal is of monoclinic(C15H17BrN2O3,Mr = 353.22),space group C21 with a = 24.691(7),b = 6.7678(17),c = 17.884(5) ,β = 97.184(5)o,V = 2965.1(13) 3,Z = 8,Dc = 1.583 g.cm-3,F(000) = 1440,μ = 2.784 mm-1,the final R = 0.0260 and wR = 0.0596 for 2684 observed reflections with I > 2σ(I).All the carbon atoms in the molecule are nearly coplanar except C(15),with a large conjugated system among the carbonyl group,pyrazole ring and the benzene ring.Three non-classical intermolecular hydrogen bonds help to stabilize the crystal lattice.The regioselectivity was rationalized based on the coordination of potassium ion with the N-anion and the carbonyl oxygen atom.  相似文献   

2.
1 INTRODUCTION The significance of cobalt coordination com- pounds in biological systems is recognized[1~3]. In many instances the cobalt coordination compounds of Schiff bases have been suggested as models to describe energy transfer in naturally occurring systems. In such cases the coordination sphere about the metal ion is believed to play an important role in determining the nature of the model system[4, 5]. In order to investigate the structures of such complexes, we report herein t…  相似文献   

3.
The title mononuclear cobalt(Ⅱ) complex [Co(DENP)2(MeOH)2]·2NO3 (DENP =2-[2-(diethylamino)ethyliminomethyl]-4-nitrophenolate) was prepared and characterized by elemental analysis, IR and single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group Pī with a = 8.297(1), b = 11.075(2), c = 11.134(2) (A), α = 69.69(1),β = 70.97(2), γ =84.02(2)°, Z = 1, V = 907.0(4) (A)3, Dc = 1.424 g/cm3, Mr = 777.66, λ(MoKα) = 0.71073 (A), μ = 0.548mm-1, F(000) = 409, R = 0.0628 and wR = 0.1734. The complex consists of a [Co(DENP)2-(MeOH)2]2+ cation and two disordered nitrate anions. The Co atom, lying at the inversion centre, is six-coordinated by two DENP ligands and two MeOH molecules in an octahedral geometry. The molecules in the crystal are linked through intermolecular O-H…O, O-H…N and N-H…O hydrogen bonds, forming chains parallel to the b axis.  相似文献   

4.
On the treatment of 1-aryl-2-(2-furyl)-5-(2-thienyl)pyrroles with tetracyanoethylene, 1-aryl-2-(2-thienyl)-5-(5-tricyanoethenyl-2-furyl)pyrroles were produced. These compounds formed crystals with greenish metallic luster. In their solid-state UV-vis-NIR diffuse reflection-absorption spectra, absorption band corresponding to metallic reflection spreads in the range of 550-900 nm. Furthermore, strong absorption appeared below 520-540 nm. This absorption results in the appearance of green color. Single-crystal X-ray crystallographic analysis revealed the crystal structure of 1-(4-methoxyphenyl)-2-(2-thienyl)-5-(5-tricyanoethenyl-2-furyl)pyrrole (2c). The distinct features of the crystal structure are as follows: (1) the thiophene-pyrrole-furan-tricyanoethenyl π-system is approximately flat; (2) the conformational relation between the pyrrole ring and the furan ring is anti, that is, these rings are pointing in opposite directions and the dihedral angle of N-C-C-O=180°; (3) as a result, the tricyanoethenyl group is far from the 4-methoxyphenyl group; (4) the molecules of 2c are arranged in a ribbon structure; (5) the ribbons are assembled side-by-side to form a terraced layer; (6) the layers stack so that the π-orbitals of 2c become close to each other.  相似文献   

5.
钼铁混合金属原子簇Mo_2Fe_2Te_2(CO)_7(η~5-C_5H_5)_2是Fe_3Te_2(CO)_9与Mo_2(CO)_6(η~5~C_5H_5)_2反应所得的产物之一。它的晶体属正交晶系,空间群为Pbn2_1。晶胞参数:a=12.172(5);b=13.595(2);c=12.924(4)A,V=2138.5(2)A~3。晶体结构由直接法及差值Fourier合成解出,经最小二乘法修正,最终R因子为0.030(3233个Ⅰ>26(Ⅰ)的反射)。在簇分子中,四个金属原子呈四面体构型,两个μ_8-Te原子和一个不对称的μ_8-CO分别桥连到四面体的三个三角面的金属原子上,从而构成了缺顶点的类立方烷结构。  相似文献   

6.
The adsorption structures of benzene and pyridine on Si(5 5 12)-2 x 1 were studied at 80 K by using a low-temperature scanning tunneling microscope and density functional theory calculations. These structures are different from those observed on low-index Si surfaces: benzene molecules exclusively bind to two adatoms, that is, with di-sigma bonds between carbon atoms and silicon adatoms, leading to the loss of benzene aromaticity; in contrast, pyridine molecules interact with adatom(s) through either Si-N dative bonding or di-sigma bonds. Dative bonding configurations with pyridine aromaticity are the dominant adsorption features and are more stable than di-sigma bonding configurations. Thus the dative bonding of nitrogen-containing heteroaromatic molecules provides a strategy for the controlled attachment of aromatic molecules to high-index surfaces.  相似文献   

7.
3-[5-(diethylamino)-2-formylphenoxy]phthalonitrile ( n-TY-CN ), metallophthalocyanines n-TY-Co , n-TY-Cu , and n-TY-Mn bearing [5-(diethylamino)-2-formylphenoxy] groups at nonperipheral positions were prepared for the first time. These compounds were characterized with IR, NMR (only for n-TY-CN ), mass and UV-vis (except n-TY-CN ) spectroscopy. Voltammetric characterizations of n-TY-Co , n-TY-Cu , and n-TY-Mn revealed that while n-TY-Co , n-TY-Cu , and n-TY-Mn showed characteristic Pc ring and/or metal-based reduction reaction, n-TY-Co , n-TY-Cu , and n-TY-Mn were coated on the working electrode during the oxidation processes owing to the cationic electropolymerizations of the [5-(diethylamino)-2-formylphenoxy] substituents.  相似文献   

8.
Two new mononuclear lanthanide(III) complexes Ln(pytz)3(H2O)3·(H2O)3.5[Ln=Tb(1); Eu(2); Hpytz= 5-(2-pyridyl)tetrazole] were synthesized by reacting Hpytz with the corresponding lanthanide(III) ions and characterized. The single crystal X-ray diffraction analysis reveals that complexes 1 and 2 are isostructural and the lanthanide(III) ions in both complexes 1 and 2 are nine-coordinated, with three oxygen atoms of three coordination water molecules and six nitrogen atoms of three pytz ligands, forming a monocapped square antiprism. Extensive hydrogen bonds exist, resulting in a three-dimensional supramolecular network structure by hydrogen-bonds in both complexes 1 and 2, respectively. Complex 1 exhibits typical green fluorescence of Tb(III) ion and complex 2 red fluorescence of Eu(III) ion, in solid state at room temperature.  相似文献   

9.
The crystal structures of (μ-4,4-bipyridine)-di(nitrato-1-[(2-hydroxyethylimino)methyl]naphthalen-2-olocopper (I) and catena-di(μ-4,4’-bipyridine)di(μ-4,4’-bipyridine)-di(nitrato-2-[2-(hydroxyethylimino) methyl]phenolocopper)diaquacopper(II) nitrate (II) were determined. In the crystal of I, each of the two copper atoms coordinates a singly deprotonated tridentate azomethine molecule, a nitrate ion, and bipyridine, which functions as a bridge between the central atoms. The copper coordination polyhedron is a slightly distorted tetragonal pyramid with the base formed by the imine and bipyridine nitrogen atoms and the phenol and alcohol oxygen atoms. The axial site in the pyramid is occupied by the oxygen atom of the monodentate nitrate groups. In the trinuclear structure II with C2 crystal chemical symmetry, the terminal coordination unit is composed through copper coordination of monodeprotonated 2-[2-(hydroxyethylimino)methyl]phenol, bipyridine, and the nitrate anion. In the crystal, the trinuclear molecules form infinite ribbons along the z axis in which the pyridine molecules perform the bridging function. The central copper atom has an octahedral configuration formed by the nitrogen atoms of four 4,4’-bipyridine molecules and oxygen of two water molecules.  相似文献   

10.
制备了11种十二氢十二硼酸双(二烷基-5-氨基四唑)盐晶体, 采用X射线单晶衍射仪对其单晶结构进行了表征, 利用EXPLO5软件计算了11种化合物的爆轰性能. 结果表明, 11种化合物的密度在1.097~1.229 g/cm3之间, 当取代基位置相同时, 随着烷基取代基碳原子数的增大化合物的密度下降; 这些盐晶体的空间晶型主要受取代基位置的影响, 晶体结构有三斜晶系和单斜晶系2种; 晶胞尺寸与晶胞内分子数有关, 化合物中阳离子取代烷基中碳原子的个数对与四唑相连的C—N键长无明显影响. 对于同一取代位置的化合物, 生成热和爆热随着烷基取代基的碳原子数的增多而下降.  相似文献   

11.
The crystal structure of CuBr · (C2H5)4P2 has been determined by single crystal X-ray methods. The crystals are triclinic (space group P 1 ) with two formula units per unit cell (a) = 9,29, b = 9,92, c = 7,57 Å, α = 85,3°, β = 106,6°, γ = 109,1°. The copper atoms are tetrahedrally coordinated by two bromine and two phosphorus atoms (of different biphosphine molecules). The structure has continuous chains running parallel c, in which the copper atoms are linked together by alternating double bridges consisting of two biphosphine molecules and two bromine atoms, respectively.  相似文献   

12.
The title compound E-2-(2, 4, 6-tri-tert-butylphenylphosphinyl)-2-[ N- ( tert-butyldimethylsilyl )-N- ( p-chrolophenyl )] amino-l- ( 2, 4, 6-tri-tert-butylphenyl)phosphacthylene (C49H78NClP2Si, Mr= 806.65) was synthesized and characterized by X-ray diffraction analysis. The crystal is monoclinic, space group P 21 /n with a=10.319(3), b=23.309(5), c=21.41(1) A, β=99.64(5)°, V=5078(3)A3, Z =4, Dc=1. 05g/cm3, F(000)=1760, μ=1. 92cm-1. Due to the steric hindrance from substituents around phosphaethylene, the P = C bond length is significantly longer than those observed in its analogues. The values of the three bond angles involved in the sp2-hybridized carbon atom (C(1)) of the phosphaethylene are 133.4, 115.1 and 111.4° respectively, deviating significantly from the ideal value of 120°. In addition,although 5 sp2- hybridized atoms (C(2), P(1), C(1), N and C(44)) are sequentially bonded in this molecule, no interaction is observed among the remaining pz orbits of these atoms on the string.  相似文献   

13.
用SYNTEXP3/R3四圆衍射仪收集4-(2-吡啶偶氮)间苯二酚盐酸盐晶体的三维衍射数据。晶体属P21/c空间群,a=11.339Å,b=6.835Å,c=18.170Å,β=102.76°,Z=4。利用Patterson法及直接法测定了晶体结构。经位置坐标参数,各向异性温度因子及比例因子块矩阵最小二乘修正后,最后的R值为0.055。晶体结构分析结果表明:4-(2-吡啶偶氮)间苯二酚的分子内所有非氢原子共面并形成大的共轭体系。氯离子及二个结晶水与分子中的N,O形成氢键,起到桥联分子的作用。  相似文献   

14.
Liquid crystals incorporating in their molecular framework a seven-membered ring are still relatively rare [1]. Recently the synthesis and thermal behaviour of a series of liquid crystal materials having a tropone moiety in their mesogenic core have been reported [2-4]. These mesogens, based on a 2-(acyloxy)tropone core structure, show intramolecular migration of the acyl substituents between the two oxygen atoms at C-1 and C-2, an effect already known for simple 2-(acyloxy)tropones in their isotropic solutions [5]. This migration involves a concerted [1, 9]-sigmatropic rearrangement [2]. This rearrangement could play a major role in determining the properties of the mesophases: it has been suggested in fact that, because of this rearrangement, the mesogenic molecules acquire a mean rod-like shape which can sustain the mesophase formation [2].  相似文献   

15.
文珂  金钟声 《结构化学》1992,11(4):244-247
<正> Compound (η5-C5H5)GdCl2(THF)3 was successfully prepared from action of GdCl3 and NaC5H5 in tetrahydrofuran (THF). X-ray diffraction data were collected at low temperature (about 210K). Its crystal belongs to the monoclinic space group P 21/n with a = 7. 821(2), b = 17.068(1), c=15. 057(1)(?), β=94. 76 (2)°, V = 2003. 2(10)(?)3, Z = 4, Dc=1. 69g/cm3, F(000)=1012, Mr=509. 6. The structure was solved by heavy-atom method. Least-squares refinement converged to a final R value of 0. 050. The coordination number of the Gd atom is 8. The centre of the cyclopentadienyl, the two Cl atoms and the three oxygen atoms of THF molecules form a distorted octahedron about the Gd atom.  相似文献   

16.
潘兆瑞 《无机化学学报》2011,27(10):2027-2032
由溶液法合成了2个稀土配合物{[Ln(Hmtyaa)3(H2O)2].H2O}n(Ln=Nd,1;Pr,2)(Hmtyaa=2-(5-甲基-1,3,4-噻二唑)-硫乙酸),用X-射线单晶衍射仪测定了配合物的单晶结构,并对其进行了元素分析、红外光谱、热重和粉末X-射线衍射等表征。晶体结构表明:配合物1和2结构相同,都属于三斜晶系,P1空间群。配合物中金属离子均采取九配位模式,金属离子被配体桥连形成一维双链结构,该一维双链被氢键和π-π作用连接成二维层状结构。  相似文献   

17.
 Chelating resins prepared by sorption of 2-(5-bromo-2-pyridylazo)-5-(diethylamino)phenol (5-BrPADAP) on macroporous resins (Amberlite XAD-4 and XAD-7) were characterized. The adsorption properties (amount of chelating agent adsorbed per gram of resin, sorption kinetics, retention capacity, etc.) and the thermodynamic quantities of each adsorption process were determined. The retention of some rare earth elements (e.g. Er, Yb and Lu) on these chelating resins was studied in order to preconcentrate them for their determination by X-Ray fluorescence spectrometry. Received: 7 September 1995/Revised: 2 January 1996/Accepted: 10 January 1996  相似文献   

18.
[Mo_5P_2O_(23)]~(6-)[(CH_3)_2NH_2]_5~(5+)[H_3O]~+·1/2DMF·1/2H_2O(DMF=(CH_3)_2NC-HO)(M_r=1204.67)的晶体属三斜晶系,空间群P,晶胞参数a=16.438(6);b=22.22(1);c=11.325(5),α=104.25(4);β=108.97(3);γ=97.68(4)°,V=3688(3),Z=4,D_c=2.17gcm~(-1),R=0.056,R_w=0.074,晶胞中每个不对称单元含有两个[Mo_5P_2O_(23)]~(6-)[(CH_3)_2NH_2]_5~(5+)[H_3O]~+·1/2DMF·1/2H_2O,阴离子[Mo_5P_2O_(23)]~(6-)中的Mo、P原子成一个畸变五角双锥构型。有一个阴离子的所有原子(Mo、P、O)位置完全确定,而另一个阴离子有一个磷酸根的三个氧原子位置出现二重位置统计分布。化合物的阳离子为二甲胺阳离子和水合氢离子。  相似文献   

19.
邢卓  杨瑞琴 《应用化学》2015,32(9):1093-1098
研究2-(5-溴-2吡啶偶氮)-5-二乙氨基酚(5-Br-PADAP)试剂显现镀锌工具遗留印迹的方法。 考察接触时间、时间间隔、试剂浓度、是否洗手等因素对印迹强度及分辨率的影响,并对该方法的可靠性进行验证。 实验结果表明,试剂浓度1 g/L、接触时间10 s以上,间隔时间不超过4 h条件下,均能显出较好的印迹。 该方法可以灵敏地显现镀锌工具遗留印迹,对非铁金属工具遗留印迹检测进行了很好地补充。  相似文献   

20.
The syntheses of twenty 1-(2-dialkylaminoethyl)-5 (and 6)-methoxy-2-methyl (and H)-benzimidazoles in which the dialkylamino groups are dimethylamino, diethylamino, pyrrolidino, piperidino and morpholino, are presented. These compounds failed to show any significant biological activity.  相似文献   

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