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1.
<正> INTRODUCTION. Ipohardine is an alkaloid which can be dissolved in water. It was obtained by Reineckate method from the aqueous solution of Ipomoea Hardwickii Hemsl. In the previous paper we have reported the crystal and molecular structure of Ipohardine Picrate. The structure determination of the title compound is described here. The structure analysis shows that the structure of the title compound is slightly different from the former.  相似文献   

2.
<正> INTRODUCTION. The five-coordinated silicon atoms in the 1-aryloxy derivatives of the silatrane series are surrounded by four oxygen atoms (three in equatorial- and one in apical position). The only known crystal structure of the 1-aryloxy silatrane derivatives is that of 1-m-chlorophenoxysilatrane and we performed the structure determination of the title compound to throw light upon the effect of the phenyl ring substituent on the Si←N dative bond.  相似文献   

3.
<正> The title compound, cyclooctadienyl potassium tetrahydrofuranate was prepared by the reaction of cycloocta-1,5-diene with metallic potassium in tetrahydrof u-ran(THF) in the presence of triethylamine. Its crystal structure was determined by a low temperature X-ray diffraction analysis method. The crystal is monoclinic with space group Pc,a=6. 192(3),b=9. 444(8),c=14. 543(1) A ,β=94. 92(5)°,V = 847. 24 A3,Z = 2,DC= 1. 14 g/cm3 and μ(MoKa) = 5. 58cm-1. The structure was solved by heavy-atom methods and refined by least-squares to a final R value of 0. 049. The potassium cations, each with two complex THF molecules attached,are linked by bridging cyclooctadienyl an-ions,while the anions are connected to the bridging cations to form a puckered chain.  相似文献   

4.
Crystal and molecular structure of [C6H2(COO)4Zn2(H2O)5]·2H2O has been determined by X-ray diffraction technique, Mr = 507. 0,monoclinic,space group P21/n,a = 5. 925(1), 6 = 23. 613(9) ,c= 11. 790(5) A ,β= 96. 36 (3)°, V=1639. 3 (1. 0) A3,Z=4,DC = 2. 05g/cm3,λ=0. 71069 A,μ(MoKa) = 30. 9/cm-1,F(000) = 1024e. The structure was solved by Patterson and Fourier techniques and refined by least-squares method to a final conventional R value of 0. 055(Re = 0. 059)for 1557(I>3σ(I))reflections. Both atoms Zn(1) and Zn(2) are bridged by the Z,E-type of the car-boxyl group, in addition, Zn (1) is monodentate-bonded to the three remaining carboxyl and Zn(2) is bonded to five water molecules. The crystal structure shows a 2-dimensional polymeric network along(010)face. The Zn(l) -O distances are in the range of 1. 94~ 2. 01 A (average 1. 98 A ). The Zn(2) -O distances are in the range of 2. 06~2. 21 A (average 2. 12A).  相似文献   

5.
<正> Introduction. Tertiary diphosphine-cyclopentadienyl-nickel(Ⅱ) complexes were first synthesized by Sato (Sato, et al., 1971), and their boronhydrides were prepared by Zhang (Zhang, et al., 1983). Here we report the crystal structure of the title compound in Order to correlate the reactivity of this type of compounds with their structures and bondings.  相似文献   

6.
<正> The electronic absorption spectra of the'crystal of Cu(CtfH505) g-2H20 were measured. The experimental results were discussed quantitatively by using the ligand field theory and the radial wave function of nonfree copper(II). The electronic structure of the compound is in agreement with its crystal structure.  相似文献   

7.
<正> The crystal and molecular structure of the title compound was determined by single crystal X-ray diffraction method. The complex crystallizes in the mono-clinic space group P21/n with a = 10. 306 ( 3) , b = 10. 161 (2), c = 14. 798 ( 4) A . β= 108. 52(2)°, V= 1469. 4(6)A3,Z= 4. The structure was solved by direct methods. Least-squares refinement converged to a final value of R = 0. 043 and Rw= 0. 040 for 1237 reflections. The molybdenum (Ⅵ) ion is bonded to two chlorine atoms, two oxo atoms and two oxygen atoms from two monodentately and weakly coordinated carboxyl groups of molecules C4H3OCOOH, forming a octahedron. The Mo-O distances are in the range 1. 66 - 2. 39A ,the Mo-Cl distances fall in the range 2. 33-2. 34A.  相似文献   

8.
The structure of Na_2H_2[H_2V_2W_(18)O_(62)]12H_2O has been determined by x-rayanalysis.The crystals are trigonal,space group R3m,with cell parametersa=37.613(11),c=12.972(7)A,V=15901(13)A~3,and Z=9.The structure model wasrefined by full-matrix least square to R=0.065 for 1702 reflections with F>4σ(F).The existence of the[H_2V_2W_(18)O_(62)]~(4-)heteropolyanion in the crystals has beenconfirmed.It is composed of two VO_4 tetrahedra and eighteen WO_6 octahedralinked to gve the Dawson-type structure.  相似文献   

9.
By the reactions of manganese(II) acetate, 2-sulfoethylphosphonic acid, 1,10-phen (1,10-phen = 1, 10-phenanthroline) or cobalt(II) acetate, 4,4'-bipy and 2-carboxyethylphosphonic acid, two novel compounds of [Mn(H2O)2(C12H8N2)(HO3PCH2CH2CO2)] (1) and[Co(H2O)4 (C10H8N2)]· (HO3PCH2CH2CO2) (2) have been synthesized and characterized by IR spectroscopy, elemental analyses and single-crystal X-ray diffraction. Compound 1 has a 0D structure. Two Mn(II) ions are linked by two 2-carboxyethylphosphonic acid ligands, forming a centrosymmetric dimer. These dimers are further interlinked into a 2D layer structure by π-π stacking interactions and hydrogen bonds. Compound 2 has a 1D chain structure. The 2-carbo- xyethylphosphonic acid remains uncoor- dinated and acts as the organic template. By the bridge of 4,4'-bipy, the [Co(4,4'-bipy)]2+ chains are formed.  相似文献   

10.
<正> Introduction. Chuanliansu(1), C_(30)H_(38)O_(11)·3H_2O, isolated from the bark of Melia toosendan S. et Z., is an active anthelimintic against ascaris (Chung, 1975; Shu, 1980). In the course-of our systematic investigation on the relationship between the structure and biological activity of its analogues (Ochi, 1976; Arnoux, 1980), we have undertaken an X-ray structural, determination of the title compound. The'molecule belongs to the triterpene group with a furan ring and a hemiacetai bridge between C(19) and C(28). Its colorless crystals have been obtained by slow evaporation of an alcohol-water solution.  相似文献   

11.
The enthalpy change of formation of the reaction of hydrous dysprosium chloride with ammonium pyrrolidinedithiocarbamate (APDC) and 1,10-phenanthroline (o-phen·H2O) in absolute ethanol at 298.15 K has been determined as (-16.12±0.05) kJ·mol-1 by a microcalor-meter. Thermodynamic parameters (the activation enthalpy, the activation entropy and the activation free energy), rate constant and kinetics parameters (the apparent activation energy, the pre-exponential constant and the reaction order) of the reaction have also been calculated. The enthalpy change of the solid-phase reaction at 298.15 K has been obtained as (53.59±0.29) kJ·mol-1 by a thermochemistry cycle. The values of the enthalpy change of formation both in liquid-phase and solid-phase reaction indicated that the complex could only be synthesized in liquid-phase reaction.  相似文献   

12.
The structural analogy of clathrate synthesized with natural zeolite framework is well known. HPF_6·6H_2O and (CH_3)_4 (OH)·5H_2O are isostructural with sodalite,melanophlogite is isostructural with the 12 cubic gas hydrate and zeolite ZSM-39 with the 17 gas hydrate. The synthesis of ZSM-39 was first reported by Brace in 1981.Schleker and Meier also obtained the crystals of ZSM-39 with size<10μm and analyzed its crystal stucture by the powder X-ray diffraction.In 1984,Gies solved the crystal structure of dodecasil 3C(ZSM-39) synthesized from an aqueous system in space group F_(ds).In the present paper,we report the framework structure of the high silica zeolite—ZSM-39 obtained from the ethylene glycol-water mixed solvent system.  相似文献   

13.
杨锐  何水样  武望婷  陈凤英  胡荣祖 《中国化学》2006,24(12):1731-1736
Europium(Ⅲ) compound with 2-oxopropionic acid salicyloyl hydrazone (C_(10)H_(10)N_2O_4,H_3L) and 1,10-phenan-throline (C_(12)H_8N_2,phen) has been prepared.A yellow prismatic crystal of the compound was obtained,and themolecule crystallized in the triclinic space group P-1.There are two 9-coordinated complex molecules in everystructure unit,where every Eu atom is coordinated by three water molecules and two tridentate C_(10)H_(10)N_2O_4 ligands,forming two stable pentacycles.The coordination polyhedron around Eu~(3+) was described as a single cap squareantiprism.In the crystal cell,there are one free 1,10-phenanthroline and four water molecules.The thermaldecomposition of the compound and its kinetics were studied by non-isothermal thermogravimetry.The Kissinger'smethod and Ozawa's method were used to calculate the activation energy value of the first-step decomposition.Thestages of the decompositions were identified by TG-DTG-DSC curve.The non-isothermal kinetic data were ana-lyzed by means of integral and differential methods.The possible reaction mechanism and the kinetic equationswere investigated by comparing the kinetic parameters.  相似文献   

14.
The title compound was synthesized and characterized by means of elemental analysis, IR, DTA-TG and UV. Its single crystal structure was solved by using direct methods. The compound crystallizes in the orthorhombic space group Pmc(?) with lattice parameters: a = 1. 7261(2), b=l. 7537(3), c=2. 4258(3) nm. V=7. 34220 nm3, F(000) = 3648, Z = 4. The structure was refined to conventional discrepancy factors of R=0. 060 for 3176 observed reflections [Ⅰ>3σ/(Ⅰ)]. The anion represents a modification of the well-known [Mo6O19]2- anion, in which a single terminal oxo group is replaced by a 2,4-dinitrophenyl hydrazine ligand while the structure integrity of the hexanuclear framework is maintained.  相似文献   

15.
The title compound of Cu(C14H9O3)2(C5H5N)2(C2H5OH)2(1) was synthesized via the hy- drothermal reaction of CuCl2·2H2O and 9-hydroxy-fluorene-9-carboxylic acid(HHF) with pyridine, and characterized by elemental analysis and infrared spectra. The crystal belongs to triclinic, space group P1 with a = 8.8302(12), b = 10.1625(14), c = 12.2708(17), α = 86.207(2), β = 69.562(2), γ = 64.932(2)o, V = 930.3(2) 3, Z = 1, Mr = 764.30, Dc = 1.364 g/cm3, F(000) = 399, S = 1.059 and μ(MoKα) = 0.644 mm-1. The final R = 0.0459 and wR = 0.1274 for 3414 observed reflections with I 2σ(I). The copper atom is six-coordinated by two oxygen atoms from two different 9-hydroxy-fluorene-9-carboxylate ligands, two pyridine nitrogen atoms and two ethanol oxygen atoms, forming a distorted octahedral coordination geometry. The extensive O–H···O hydrogen bonding connects the molecules to form a one-dimensional chain structure. Between adjacent one-dimensional chains, a two-dimensional layered structure was formed by fluorene ring π-π packing interaction. Between the layers, a three-dimensional structure was formed through the π-π packing interaction of the pyridine ring. Moreover, the thermal stability and photoluminescent property of the complex has been investigated.  相似文献   

16.
<正> The crystal of (C5H9C5H4)Er4(μ2-Cl)6(μ3-Cl)(μ4-O)(THF)3 belongs to triclinic space group P1, with a = 11. 909(4), b = 15.343(5), c=15. 619 (4)(?), α=104. 18(2), β=98. 81(3), γ= 111. 06(2)°, V = 2486(1)(?)3, Z = 2, Dc = 2. 07g/cm3, λ(MoKα) = 0.71073(?), μ= 73. 4cm-1, F(000) = 1476, Mr=1549. 25. The structure was solved by Patterson and Fourier techniques and refined by block diagonel least-squares method to final R = 0. 078 and Rw = 0. 084 for 5594 reflections with I≥1. 5σ(I). The results revealed that the complex is composed of four Er atoms bridged by seven Cl and one oxygen atoms with three of the Er atoms bonded each to a cyclopentylcyclopentadienyl group, and one Er atom, bonded to three THF. The Er atoms constitute a pseudo-tetrahedron.  相似文献   

17.
<正> Artesunate, C19H28O8, is orthorhombic and crystallizes in the space group D24 -P212121 with a = 18.781(4), b = 10.528(5), c = 9.853(5) A, Z =4, V = 1948 A3, DC = 1.310 g.cm-3, Mr = 384, F(000) = 824, m.p.= 134°-5°, dD21.5= +12.5 (c:2%, CHCl3), μ(CuKd) = 0.0867mm-1, λ(CuKd) = 1.5418A, T =293K. The X-ray study was carried out to determine the stereochemistry at the four chiral centers and to compare the skeleton of the title compound with that of Qinghaosu. The structure was solved by direct methods and refined for the 1620 reflections with I > 2σ(I) to a final R factor of 0.067.  相似文献   

18.
1 INTRODUCTION There has been considerable interest of copper(II) -hydroxylate complexes in the structural chemistry and biochemistry. There are two structural types in copper(II) -hydroxylate com- plexes: mononuclear[1~6] and dinuclear structure[7~9]. The present work is a part of our study on the copper complexes of -hydroxylated acid and reports the synthesis and structure of a mononuclear copper(II) complex with 9-hydroxy- fluorene-9-carboxylato acid, [Cu(C14H8O3)(C5H13- NO)(H…  相似文献   

19.
The crystal of the title compound was prepared and its structure determined by X-ray diffraction method.1672 independent reflections were collected. The crystal is orthogonal with space group P2_12_12, and a=7.353(3),b=25.111(10), c=8.631(2), Z=8. The structure was solved by using Patterson method and modified with LSM program.The final R= 0.0795. The structural features of the title compound are:Mg(Ⅱ) is octahedral and ethyl acetate is located on trans-position.Mg atoms are connected by double chloro-bridge and form polychains.  相似文献   

20.
The intensity data of the title complex were collected at a low temperature of -90℃. Thecompound crystallizes in the monoclinic space group P2_1/n, a = 17.504(2), b = 27.323 (5),c = 21 .616(4)A, β= 104.49 (2)°, Z=4. The structure was solved by Patterson and Fouriertechniques and refined by least- squares to an R = 0.088 for 8320 independent reflections.The central Pr ion is bonded to eight oxygen atoms from two molybdosilicic heteropolyligands to form a square antiprism. The Pr- O average distance is 2.44 (2)A. Both molyb-dosilicic heteropoly ligands are of a defective α- Keggin structure.  相似文献   

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