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1.
The crystal structure of 3β-acetoxy-17α-iodo-Δ5-androstene (C21H31O2I) has been determined from three-dimensional X-ray data and refined to a final reliability index of R = 5.1% for the 2352 observed reflexions. Crystals grown from methylene chloride/methanol are orthorhombic, space group P212121, with cell constants a = 6.430, b = 10.563, c = 29.369 Å.  相似文献   

2.
The Ni complex [C6H5O2P(S)N(C3H72]2Ni is monoclinic, space group P21/n with a = 8.890(3), b = 21.692(5), c = 11.670(4) Å, β = 108.35(5)°, V = 2136(1) Å3, F(000) = 916, Mr = 534.01, Z = 2, Dm = 1.318, Dx = 1.358 Mg m?3, graphite monochromatized MoKα ? radiation, π = 0.7107 Å, μ = 0.76 mm?1, T = 293 K. The structure was solved by a heavy atom method and refined to R = 0.044 for 3095 independent reflexions. The Ni atom lies in the centre of symmetry and is coordinated by four S atoms of the two molecules of the ligand in a planar arrangement. Ni? S bond lengths are 2.205 and 2.226 Å resp., the angles S? Ni? S are 97.65 and 82.35° resp.  相似文献   

3.
The crystal structure of the antibiotic hedamycin ( 1 ) has been solved by direct method and refined by least squares techniques to R = 0.091 for 2289 of 2643 independent reflexions. Crystals of C41H50N2O11 are orthorhombic, space group P212121 with lattice parameters a = 24.239 (12), b = 21.440 (10), c = 7.369 (4) Å, Z = 4. The structural features of hedamycin derived earlier by chemical and spectroscopical means are confirmed. Optical rotation and circular dichroism indicate that hedamycin ( 1 ) has the absolute configuration of the related antibiotic kidamycin ( 3 ). The conformation of ring F is a chair form with the aryl substituent almost axial. The bioxirane part of the antibiotic is in a synclinal conformation.  相似文献   

4.
The crystal structure of [C6H4(OCOC2H5)2TiCl4], which in the presence of activators is a good catalyst for olefin polymerization, has been determined by X-ray diffraction methods and refined by full-matrix least-squares techniques to R = 0.045 for 2000 independent non-zero reflexions. Crystals are orthorhombic, space group Pnma, with four molecules in a cell of dimensions: a 11.45(1), b 14.07(1), c 10.56(1) Å. The structure consists of discrete molecules possessing crystallographic m (Cs) point symmetry. The Ti atoms are octahedrally coordinated by four chlorine atoms and two carbonyl oxygen atoms of diethylphthalate. The chelating ligand atoms together with the titanium atom form a seven-membered ring with the Cl and Ti atoms located above the benzene ring.  相似文献   

5.
Preparation and Crystal Structure of Lead(II) Monoglycerolate Crystals of lead(II) monoglycerolate, of a quality suitable for diffraction studies, have been prepared from an alkaline plumbate solution and an excess of glycerol. The compound crystallizes in the monoclinic space group P21/c with a = 5.617(6) Å, b = 9.471(8) Å, c = 9.726(7) Å, β = 102.65(11)°. The structure was refined by full matrix least-squares techniques to an R value (1026 F0) of 0.078. The compound to which the formula Pb(C3H6O3) could be assigned, is polymeric in one direction. The lead and a part of the oxygen atoms built up a zig-zag chain parallel to the aaxis. The oxygen form a distorted tetragonal pyramid with lead at the apex. A decomposition temperature of 235°C has been determined.  相似文献   

6.
At room temperature, dibenzoyl peroxide undergoes oxidative addition reaction with metallic copper powder and pyridine N-oxide (triphenylphosphine oxide or 2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolin) which affords the last products as binuclear copper(II) complexes, [Cu(C5H5NO)-(C6H5COO)2]2(1), [Cu(OPPh3)(C6H5COO)2]2(2) and [Cu(C6H5COO)(C26H2oN2)](3, C26H2oN2 is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolin). The structure of the complexes were characterized by elemental analyses, IR spectra, TG-DTA and magnetic property. Crystals(1) are triclinic, space group P1,a=0.92617(36),b=1.06973(17), c=1.08813(29) nm, a=59.60(2)°, β=74.83(3)°,γ=72.80(2)°, V=0.880 nm3, Dc=1.520 g/cm3, Z=1, R=0.044, Rw=0.048, Mr=805.78, 3477 reflections with I > 3σ(I). Each copper(Ⅱ) ion is coordinated by two bridging bidentate benzoate ligands and one pyridine N-oxide or triphenylphosphine oxide to form dimeric binuclear molecules. The structure of the compound(1) shows a clear centre of symmetry.  相似文献   

7.
Structural Chemistry of PbBr2·C4H10O3 (Diethyleneglycol) Crystals of PbBr2·C4H10O3 have been synthesized and structurally characterized by single‐crystal X‐ray diffraction. PbBr2·C4H10O3 crystallizes monoclinic in space group P21/n (No. 14) with a = 9.370(1)Å, b = 10.045(1)Å, c = 21.090(1)Å, β = 98.98(1)° and Z = 8. The compound contains compact Pb—Br groups, which build colums parallel to [0 1 0] direction by Hydrogen Bonding.  相似文献   

8.
The crystal and molecular structure of 6-oxadihydrouracil (C3H4N2O3) has been determined by single crystal x-ray diffraction techniques. The compound crystallizes in the space group P21 21 21 with four molecules in a unit cell of dimensions: a = 5.106(1)Å, b = 12.461(2)Å and c = 7.112(1)Å. The structure was solved by direct methods and refined to a final value of R = 0.052. The oxauracil ring is non-planar with the C5 atom assuming tetrahedral geometry and the ring oxygen having oxazinal distances and angle (C-O = 1.432Å, N-O = 1.408Å, and CON angle of 109.0°). The usual hydrogen bonding patterns associated with the uracil ring are absent in this compound.  相似文献   

9.
The nmr and X-ray diffraction data of the novel ring system furo[3,2-e]imidazo[1,2-c]pyrimidine are reported in this paper. The crystal and molecular structure of this compound (C9H7N3O2·1/2H2O) has been solved at room temperature. Crystals are monoclinic in a space group of P2/n with cell constants a = 9.982(8), b = 13.526(9) and c = 13.981(9) Å, β = 107.44(5)°, V = 1800.9 Å3, Z = 8, Dx = 1.462 Mg·m?3. The structure was solved by full matrix least square refinement giving a final R = 0.054 (Rw = 0.069) for 1263 reflections (I>3.0σ(I)). The compound is essentially planar, existing in two slightly structural different forms, A and B. These are held in pairs with symmetry related molecules by hydrogen bonds formed with two water molecules. Then the dimeric units are stacked parallel to the c axis to form the tridimensional packing.  相似文献   

10.
The crystal and molecular structure of 2-thia-1,3,5-triaza-7-phosphaadamantane 2,2-dioxide (C5H10SPO2N3) has been determined by single crystal x-ray diffraction techniques. The compound crystallizes in the space group P21/c with four formula weights per unit cell of dimensions a = 6.129 (1) Å, b = 12.440 (2) Å, c = 14.028 (2) Å, β = 127.31 (1)°. The structure was solved by direct methods and refined to a final value of R = 0.079.  相似文献   

11.
Benzyltrimethylammonium dicitratoborate [C6H5CH2N(CH3)3][(C6H6O7)2B] · H2O (I) has been synthesized and separated out in the form of single crystals for the first time. Its crystal structure has been studied by X-ray diffraction. Crystals are triclinic with a = 10.0832(2) Å, b = 11.1232(3) Å, c = 11.9617(3) Å, α = 84.874(1)°, β = 73.520(1)°, γ = 85.550(1)°, Z = 2, space group P-1. The structure has been solved by direct methods and refined by the full-matrix least-squares technique in the anisotropic approximation up to R = 0.0485 (Bruker-Nonius KappaCCD automatic diffractometer, λMoK α). The crystal structure of compound I is based on centrosymmetric dimers that consist of complex anions and water molecules and linked by the system of hydrogen bonds into a three-dimensional framework. The crystals of compound I contains five asymmetric O-H...O hydrogen bonds. A specific feature of the structure is the formation of -COO...H...H2O hydrogen bonds, in which the carboxyl proton is considerably shifted towards the water molecule.  相似文献   

12.
Abstract

The structures of two Co(III) complexes containing N-bonded nitrite ions and one of the N4 tetradentate ligdnds R,R-picchxn (N,N'-bis(2-picolyl)-1 R,2R-diaminocyclohexane) or R-picpn (3R-methyl-1,6-bis(2-pyridyl)-2.5-diazahexane) have been determined by X-ray analyses. A-β-[Co(R,R-picchxn)(NO2)21 CLO4,.H2O is triclinic. space group P1, with a = 8.611(2), b = 9.188(1), c = 8.576(1) Å, α = 117.60(1), β = 96.40(1). γ = 73.69(1)° and Z = 1. The structure ivas refined by full-matrix least-squares methods to R = 0.035 for 2712 non-zero reflexions. δ-β-eso-[Co(R-picpn) NO2)2]CIO4,.H2O is orthorhombic, space group P212121. with a = 7.664(1). b = 15.121(3). c = 18.429(4) a and Z = 4. The structure was refined as above to R = 0.040 for 2063 non-zero reflexions. In the R.R-picchxn complex both amine nitrogen atoms of the tetradentate have the same relative configuration, Hhereds in the R-picpn diastereoisomer their relative configurations are opposite. In the latter complex this permits the exo methyl group substituent to adopt a nearly ideal equatorial position in the central chelate ring. Hydrogen bonding networks in the two structures. which link the complex cations to the perchlorate ions and lattice water molecules, are apparent.  相似文献   

13.
The crystal structure of 12,13-dibromopseurotin has been determined by single crystal X-ray analysis. The crystals belong to space group P21 with a = 16.75, b = 9.63, c = 7.42 Å, β 95.9°, Z = 2. The structure was solved by the heavy atom technique and refined to R = 0.062 with 819 significant reflexions for 299 parameters.  相似文献   

14.
Crystal and molecular structure of the ethanol solvate of 2-[bis(diphenylphosphoryl)methyl]phenol, C31H26O3P2·3/4 C2H5OH (I), was determined by X-ray diffraction analysis. Crystals I are monoclinic: a=11.896(3), b=17.207(3), c=28.421(6) Å, β=90.75(2)°, Z=8, space group P21/c. The structure of I was solved by direct methods and refined anisotropically by large-block least-squares analysis to R=0.066 (CAD-4 automatic diffractometer, λMoKα radiation, 3650 independent reflections with I≥3σ). The crystal structure of I contains two independent molecules, Ia and Ib, of the basic substance and two independent solvate molecules of ethanol. The P atoms in molecules Ia and Ib have distorted tetrahedral environments; the average bond lengths are: P=O 1.476(3), P-C(sp3)=1.833(4) and P-C(Ar)=1.809(4) Å. Molecule Ia has an approximate symmetry plane Cs. The conformation of molecule Ib differs from that of Ia in rotation of one diphenylphosphoryl substituent around the P-C(sp3) bond by an angle of ≈34°. In molecule Ia, the O=P-C-P=O fragment has the form of a chela with two nearly parallel P=O bonds. In the crystal structure of I there are O-H...O=P intermolecular H-bonds; in molecules Ia and Ib there is an intramolecular H-bond of C-H...OH type.  相似文献   

15.
Single and Double Deprotonated Maleic Acid in Praseodymium Hydrogenmaleate Octahydrate, Pr(C4O4H3)3 · 8 H2O, and Praseodymiummaleatechloride Tetrahydrate, Pr(C4O4H2)Cl · 4 H2O Single crystals of Pr(C4O4H3)3 · 8 H2O grew by slow evaporation of a solution which had been obtained by dissolving Pr(OH)3 in aqueous maleic acid. The triclinic compound (P1, Z = 2, a = 728.63(3), b = 1040.23(3), c = 1676.05(8) pm, α = 72.108(2)°, β = 87.774(2)°, γ = 70.851(2)°, Rall = 0.0261) contains Pr3+ ions in ninefold coordination of oxygen atoms which belong to two monodentate maleate ions and seven H2O molecules. There is one further non‐coordinating maleate ion and one crystal water molecule in the unit cell. Thermal treatment of Pr(C4O4H3)3 · 8 H2O leads first to the anhydrous compound which then decomposes to the respective oxide in two steps upon further heating. Evaporation of a solution of Pr(C4O4H3)3 · 8 H2O which contained additional Cl ions yielded single crystals of Pr(C4O4H2)Cl · 4 H2O. In the crystal structure (monoclinic, P21/c, Z = 4, a = 866.0(1), b = 1344.3(1), c = 896.9(1) pm, β = 94.48(2)°, Rall = 0.0227), the Pr3+ ions are surrounded by nine oxygen atoms. The latter belong to four H2O molecules and three maleate ions. Two of the latter act as bidentate ligands.  相似文献   

16.
M.F. Mackay  N.W. Isaacs 《Tetrahedron》1979,35(15):1893-1898
X-ray crystallographic analysis has established the crystal and molecular structure of the title compound, C38H38O8. The monoclinic crystals belong to the centrosymmetric space group P21/c, with a = 16.701(5), b = 8.037(2), c = 23.600(9) Å, β = 93.10(2)° and Z=4. The structure was solved by direct methods from diffractometer data measured with CuKα radiation, and refined to a final R index of 0.081 for the 2088 observed terms. The dimeric molecule has approximate two-fold symmetry and its presence in the unit cell in both chiralities forms a racemic structure. The three central bonds, C(10)-C(11), C(11)-C'(11), C'(11)-C'(10), are significantly elongated with a mean value 1.59 Å.  相似文献   

17.
Molybdenum-nitride-trichloride-di-n -butylether [MoNCls3 · 0 (C4H9)2]4; Preparation, I.R. Spectrum, and Crystal Structure Phenyldiazonium tetrachloronitridomolybdate, C6H5N2[MoNCl4], was obtained in the form of orange-red crystals from phenyldiazonium chloride and molybdenum nitride chloride in POCl3 suspension. In boiling di-n-butylether it decomposes to chlorobenzene and the title compound which is obtained in the form of dark red crystals, sensitive to moisture. [MoNCl3 · O(C4H9)2]4 can also be obtained directly from MoNCl3 and dibutylether. It crystallizes in the monoclinic space group P21/c with two tetrameric molecules per unit cell. The lattice constants are at ?49°C a = 1 283, b = 1 170, c = 1 922 and β = 94.11°. The crystal structure was determined with the aid of X-ray diffraction data and was refined to a residual index of R = 0.047 for 1951 observed reflexions. In the [MoNCl3 · O(C4H9)2]4 molecule the Mo atoms form a square; they are linked with one another via the N atoms with alternating Mo? N distances of 165 and 215 pm, which indicate triple and single bonds, respectively. In the position trans to the shorter Mo?N bond, the ether molecule is bonded by its oxygen atom. The I.R. spectra of C6H5N2[MoNCl4], C6H5N2[MoCl6], and [MoNCl3 · O(C4H9)2]4 are recorded.  相似文献   

18.
Crystals of C24H36N6O6Cr2 are monoclinic, a 15.380(3), b 13.965(2), c 14.459(3) Å, β 92.18(1)°; Z = 4; space group P21 with two independent molecules in the asymmetric unit. The crystal structure was determined from X-ray diffractometer data by direct methods and refined by least-squares methods to R = 0.066 for 2430 independent observed reflections. It consists of discrete molecules, in which each Cr atom is surrounded by three cis carbonyl groups and three cis nitrogen atoms of three 3,3,4,4-tetramethyl-1,2-diazetine ligands, in a deformed octahedral coordination. There is no evidence of intramolecular Cr ? Cr interaction.  相似文献   

19.
Complexes of Cu(II) with the polydentate diacetylazine dioxime ligand C8H14N4O2 have been synthesized by template and non-template reactions. The crystal structure of [Cu(C8H13N4O2)]2[ClO4]2(C2H5OH)2 has been determined to establish the conformation of the ligand and the coordination of the oxime function. The structural analysis shows that the nearly planar [C8H13N4O2]? group behaves as a bridging tetradentate ligand. The distorted square-pyramidal coordination about each Cu atom includes three N donors from two oxime and azine and one O donor from the other oxime, the ethanol molecule occupying the apical position. A perchlorate anion is loosely bonded to Cu. The intramolecular Cu…Cu separation is 3.725(2) Å. The compound crystallizes in the centrosymmetric space group P1 triclinic lattice with refined lattice parameters of a = 11.963(8) Å, b = 9.784(7) Å, c = 7.501(6) Å, α = 90.69(4)°, β = 104.53(4)°, γ = 90.83(4)°, V = 849.7 Å3 and Z = 2. Full-matrix least-squares refinement of 1490 independent reflexions led to final discrepancy indices, R = 0.059, and Rw = 0.065. The Cu centres are highly coupled as indicated by the ESR spectrum. There is no evidence that the C8H14N4O2 ligand stabilizes unusual oxidation states of Cu.  相似文献   

20.
The anilinium β-octamolybdate dihydrate has been prepared in acidic aqueous solution. TG, DTG, IR and 1H NMR techniques have been used to identify the compound. It belongs to a series of molybdates of alkyl-N- and -N,N-substituted anilinium cations. Single crystals have been analyzed by X-ray diffraction. Crystal data are: (C6H8N)4[Mo8O26] · 2H2O, space group P1, Z = 1, a = 10.007(1), b = 8.014(2), c = 14.645(8)Å, α = 109.81(3), β = 108.59(2), γ = 85.44(2)°, V = 1052.9(6) Å3, Do = 2.49(1), Dx = 2.52 mg m?3, R = 0.026 and Rw = 0.031 for 5297 observed reflexions. The crystal structure consists of discrete [β-Mo8O26]4? polyanions, two crystallographically independent (C6H8N)+ cations and one independent water molecule. Polyanions are linked to the cations and to the water molecules by hydrogen bonds of types NH…O and OH…O.  相似文献   

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