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1.
Rhombic single crystals of bariumchromate were grown in silica gels up to 1.5 mm in size. The influence of the initial pH-value of the gel and the kind and concentration of reactants are studied. The crystal structure has been determined. The compound crystallizes in space group Pnma, with cell dimensions a = 9.113(4) Å, b = 5.528(3) Å, c = 7.336(4) Å and Z = 4. The structure was refined to R = 0.062 on the basis of 364 reflections. Every barium atome, centered in a distorted archimedian antiprism, is coordinated to 8 oxygen atoms each belonging to a chromate tetrahedron. Interatomic distances and bond angles were calculated.  相似文献   

2.
Crystallography Reports - A novel Schiff base compound was synthesized and characterized by IR spectroscopy and X-ray diffraction method. The compound crystallizes in monoclinic space group P21/c...  相似文献   

3.
The crystal structures of methyl and ethyl N-(2,3-dimethoxybenzyl)-N-(p-toluenesulfonyl)-2-phenylglycinates 4a and 4b respectively, have been determined by X-ray diffraction analysis. The presence of different alkyl ester groups in both molecules does not affect the geometry retaining a synclinal conformation for the N atom and the O atom of the C=O group [N—C17—C18—O5 38.1(5)° for 4a and 33.3(4)° for 4b ].  相似文献   

4.
The title compound C20H16N2S is crystallized in the monoclinic space groupP21/c with cell parametersa=10.663(4),b=17.585(9),c=9.418(5)Å,=115.23°(4),V=1598(3)Å3,Z=4. The structure was refined by full-matrix least-squares methods using X-ray data set collected at room temperature. A finalR F =0.033 andR w =0.048 for 2225 unique reflections withI> 3(I) and 272 variables was obtained. The X-ray crystallographic study establishes theZ stereochemistry of the title compound.  相似文献   

5.
The crystal structure ofN-(2-morpholinoethyl)-2-oximato-1-phenylpropan-1-iminechloropalladium(II), [Pd(L)Cl], has been determined from X-ray data collected by counter methods. The compound crystallizes in the orthorhombic space groupPna21 with four molecules per unit cell, the dimensions of which area=9.602(2),b=8.150(1),c=21.181(4) Å. Full matrix least-squares refinement gave a finalR value of 0.042 for the 3218 independent observed reflections. The oxime ligand is deprotonated and is acting as a tridentate ligand coordinating to the palladium through the oxime nitrogen, the imine nitrogen, and the tertiary amine nitrogen of the morpholine moiety. To complete four-coordination about the palladium atom, a chloride ion is also attached to the central metal atom. The donor atoms plus the palladium atom are planar.  相似文献   

6.
Abstract  The crystal structure of N-(tert-butyl)-1-(3,5-dioxo-2-phenyltetrahydro-4-isoxazolyl)-cyclohexane-carboxamide 1 has been determined. The title compound crystallized in the orthorhombic space group pbca with cell parameters, a = 10.6556(6) ?, b = 18.0132(11) ?, c = 19.5513(12) ?, v = 3752.7(4) ?3, Z = 8, D cal = 1.269 Mg/m3 at T = 120 K. The structure refined by full-matrix least-squares procedures to find R 1 = 0.0463 and wR 2 = 0.0937 for 3059 reflections. The soxazole ring isn’t coplanar with the phenyl ring. Index Abstract  The crystal structure of N-(tert-butyl)-1-(3,5-dioxo-2-phenyltetrahydro-4-isoxazolyl)-cyclohexane-carboxamide 1 has been studied.   相似文献   

7.
Nitrate (1): C14H17N2O+·NO 3 , orthorhombic, Pbca,Z=8,a=9.6924(4),b=27.664(2) andc=10.8589(6)Å.Hydrogen tartrate dihydrate (2): C14H17N2O+·C4H5O 6 ·2H2O, orthorhombic, P212121,Z=4,a=7.6703(5),b=7.9368(4) andc=31.953(2)Å. In the solid state, cation conformation differ due to molecular flexibility, very different anionic environments, and resultant hydrogen bonding patterns. Despite these differences, the two structures maintain the same separations (about 7.35 Å) of the two most distant potential pharmacophoric groups, i.e., the aromatic ring and the protonated amine group.  相似文献   

8.

Abstract  

The title compound, C17H13NO6, was synthesized and structurally characterized by elemental analysis, MS, 1H NMR and single crystal X-ray diffraction. It crystallizes in monoclinic system space group C 2/c with a = 27.981(6) ?, b = 12.996(3) ?, c = 8.0900(16) ?, β = 91.06(3)°, V = 2941.4(10) ?3, Z = 8, R 1 = 0.0675, wR 2 = 0.1626, and T = 298(2) K. The X-ray structure determination revealed that the center furanone ring is nearly coplanar with p-methoxybenzene ring and forms a dihedral angle of 87.2(1)° with the nitrobenzene ring. O–H···O Intermolecular hydrogen bonds link pairs of molecules into centrosymmetric dimers, making a graph set motif of R 22(10). The dimers are further assembled into a chain of edge-fused R 44(34) rings running along the [001] direction. The final three-dimensional supramolecular architecture is stabilized by weak π–π interactions.  相似文献   

9.
2-Amino-5-(m-nitrophenyl)-1,3,4-thiadiazole (C8H6N4O2S) is studied using IR and 1H NMR spectroscopy and X-ray diffraction (CAD4 automated diffractometer, λMoK α, graphite monochromator, 957 unique reflections, Patterson method, R = 0.0326). The crystals are monoclinic, a = 11.832 Å, b = 9.862 Å, c = 8.353 Å, β = 110.40(3)°, V = 913.6(3) Å3, d calcd = 1.212 g cm?3, μ(MoK α) = 0.253 mm?1, Z = 4, and space group P21/c. In the crystal, the C8H6N4O2S molecules form infinite layers parallel to the xz plane. Each layer contains aromatic rings with nitro groups that deviate from the layer plane on either side of the layer. In the packing, the aromatic rings with nitro groups of one layer fill spaces between aromatic rings with nitro groups of the adjacent layers.  相似文献   

10.
Crystallography Reports - N-(2-Fluorophenyl)-1-(5-nitrothiophen-2-yl)methanimine has been synthesized and characterized by single-crystal X-ray determination. Molecular geometry from X-ray...  相似文献   

11.
[2-(4-Chlorobenzoyloxy)-5-methylphenyl]-(4-methylphenyl)methanone was synthesized and characterized by spectroscopic and X-ray diffraction methods. The molecule crystallizes in the monoclinic space group P21/c with cell parameters a = 13.7530(19) Å, b = 10.0560(19) Å, c = 13.469(3) Å, β = 100.630(7)° and Z = 4. There is a large discrepancy between the carbonyl group bond lengths of ketone and the ester. The structure exhibits intermolecular hydrogen bonds of the type C–H···O.  相似文献   

12.
The crystal structures of two monoaza-15-crown-5 macrocycles substituted at the nitrogen atom are determined by X-ray diffraction. The structures of these crystals are characterized by the intramolecular and intermolecular N-H?O and C-H?O interactions. The conformation of the 15-membered rings and the specific features of the molecular packing in the crystals are discussed.  相似文献   

13.

Abstract  

Tetrabutylammonium 4-(2-bromothiophene-5-sulfanilamide)-benzoate crystallizes in C2/C lattice with a = 18.3389(17), b = 16.540(16), c = 15.8280(15) ?, β = 116.959(2), V = 4279.5(7) ?3, Z = 4, and R = 0.0560. In the structure a very short centrosymmetric hydrogen bond and C=O···Br halogen bond interactions, together with N–H···O and C–H···O hydrogen bonds give a three-dimensional network.  相似文献   

14.
The crystal structures of the title compounds have been determined as part of an investigation into the factors which may influence the solid-state reactivity of benzylidene cyclopentanones. Thep-methyl derivative, which is photoactive in the crystalline state, in monoclinic:P21/c,a=18.381(2),b=11.209(2),c=8.285(2) Å,=94.46(12)°, andz=4. The chloro derivative, which is photostable, is also monoclinic:P21/c,a=17.522(4),b=7.906(2),c=11.888(2) Å,=91.19(14)°, andz=4. The structures were solved and developed via the heavy-atom method and refined by least-squares to finalR values of 0.062 and 0.061, respectively, using 1902 and 2356 observed reflections measured using an automatic diffractometer. The conformations of the two molecules in their crystal structures are significantly different and lead to dissimilar packing arrangements, which clearly account for the different photochemical behaviors.  相似文献   

15.
The crystal and molecular structure of the title compound has been determined by X-ray diffraction techniques. It crystallizes in the orthorhombic space group Pbca with 4 formula units C24H26N4O6Pd in the unit cell. The lattice constants are a = 17.259, b = 19.070, and c = 7.480 Å. The structure was solved by the heavy atom technique and refined by least-squares calculations to the conventional R = 0.057. The coordination sphere of palladium as well as the molecular geometry of the ligands are discussed in the paper.  相似文献   

16.
The formula of the title compound is C22H30N2,M T =322.5; monoclinic:P21,a=7.569(3),b=9.381(1),c=13.684(4) Å,=105.81(2)°,Z=2,V c =933.7 Å3,D x =1.15 g cm–3,(CuK)=5.1 cm–1. The sparteine skeleton (bis-quinolizidine system) has atrans-trans configuration. RingA has an intermediate form between the sofa and half-chair conformations, ringsB andD-chair, and ringC-boat conformations, respectively. The double bond C(2)=C(3) is equal to 1.343(9) Å. The phenyl ring is planar and makes an angle with a plane through N(1), C(2), C(3), and C(4) atoms equal to 43.9°.  相似文献   

17.
Crystals of 2,3-bis(2-pyridyl)-5,8-dimethoxyquinoxaline (bpdmq) were examined using X-ray diffraction analysis: Monoclinic, space group P2 1/n with a = 6.9362(14) Å, b =17.285(4) Å, c =13.583(3) Å, =96.21(3)°, V =1619.0(6) Å3, Z = 4. The crystal structure indicates that the title compound consists of quinoxaline ring system substituted with two pyridine rings and two methoxy groups. Two pyridine rings form dihedral angles of 39.8 and 44.1° with the mean planar quinoxaline ring, and a dihedral angle of 67.1° with each other. The orientation of the pyridine rings is such that their N atoms face each other. There exist significant – interactions responsible for the formation of the stacks along the a-axis of the crystal packing.  相似文献   

18.
The crystal structures of (E)-5-hydroxypyrrolizidin-3-one (2) and (Z)-5-thioketalpyrrolizidin-3-one (3) have been determined by single-crystal x-ray diffraction techniques and refined by full-matrix least squares. Molecule2 crystallizes in the monoclinic space groupP21/a(No. 14) witha=7.887(3) Å,b=9.788(5) Å,c=9.316(4) Å,=100.6(1), andZ=4. Molecule 3 crystallizes in the monoclinic space groupP21/c witha=12.947(14) Å,b=10.553(14) Å,c=9.629(14) Å,=101.4(1), andZ=4. The calculated density for both molecules is 1.33 g cm–1. FinalR-factors were 5.1% for2 and 8.59% for3. The x-ray results showed that a change in configuration occurred in the reaction going from2 to3.  相似文献   

19.
Two complexes Cu(L)2(CH3COO)2 (1) and [Cu2(μ-CH3COO)4(L)2](L)2 (2) (L = N-(4′-methylaniline)-4-pyridinecarboxamide) have been prepared and their crystal structures have been determined by single-crystal X-ray diffraction. The complexes are obtained by using the same raw materials and reaction conditions except solvents. The presence or absence of water controls the coordination mode to give rise to different structures. The structure of 1 has a triclinic space group P-1 with a = 8.381(3) ?, b = 8.545(4) ?, c = 11.357(5) ?, α = 110.654(6)°, β = 102.388(7)°, γ = 97.889(7)°, V = 722.9(5) ?3, and Z = 1. The structure of 2 has a triclinic space group P-1 with a = 9.121(3) ?, b = 9.454(3) ?, c = 17.233(5) ?, α = 77.374(5)°, β = 89.827(6)°, γ = 74.342(6)°, V = 1393.8(7) ?3, and Z = 1. Supramolecular assemblies have also been found via noncovalent bonds such as hydrogen bonds, π–π stacking interactions.  相似文献   

20.

Abstract  

The title compound, 3-methyl-4-phenyl-5-(2-pyridyl)-1,2,4-triazole was synthesized by reaction of diphenylphosphazoanilide with N-acetyl-N′-(2-pyridoyl)hydrazine. Crystals suitable for X-ray analysis were obtained from a mixed solution of water and ethanol in a one-to-one volume ratio. The crystal is orthorhombic, space group P212121 with crystallographic parameters: a = 19.414(4) Å, b = 17.172(3) Å, c = 7.4850(15) Å, β = 90.00°, μ = 0.079 mm−1, V = 2495.3(8) Å3, Z = 8, Dc = 1.258 g/cm3, F(000) = 992, T = 295(2) K. The X-ray results showed that in the crystal structure of the title compound, the 1,2,4-triazole, pyridine and benzene rings are not coplanar.  相似文献   

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