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1.
The crystal structure of 11,12-dihydroxydrim-8(9)-en-7-one was determined by X-ray diffraction. The unit cell parameters are a = 7.534(3), b = 12.192(5), c = 8.067(4) Å, β = 98.01(3) Å, space group P21, and Z = 2 for C15H24O3. The structure was solved by direct methods and refined in the anisotropic approximation to R = 0.051 and R w = 0.113. The intramolecular O-H?O hydrogen bond [2.892(6) Å] between the hydroxy groups closes an additional seven-membered H-ring in the molecule. In the crystal, the intermolecular O-H?O hydrogen bond [2.857(4) Å] between the hydroxyl group and the carbonyl oxygen atom links the molecules related by the translation along the c-axis to form infinite chains.  相似文献   

2.
Hydrazine 5-amino-1-benzyl-1,2,3-triazole-4-carboxylate hexafluorosilicate trihydrate (I) is synthesized. The crystal structure of the compound synthesized is determined. Crystals I are monoclinic, a = 13.353(1) Å, b = 21.094(2) Å, c = 20.233(2) Å, β = 94.05(3)°, space group P21/c, and R = 0.0584 for 16 601 reflections with I > 2σ(I). In the asymmetric part of the unit cell, four organic cations protonated at the terminal hydrazine nitrogen atoms, two hexafluorosilicate anions, and six water molecules are linked into a three-dimensional framework through hydrogen bonds of the N-H?F, N-H?O, and O-H?F types.  相似文献   

3.
The crystal structure of 3-ammonium-4-hydroxyphenyl sulfonate hemihydrate C6H3(NH3)(OH)SO3 · 0.5H2O is determined by single-crystal X-ray diffraction. The unit cell parameters are as follows: a = 11.2395(3), b = 10.3814(3), c = 13.7509(4) Å, β = 100.326(1)°, V = 1578.49(8) Å3, space group P21/n, Z = 4. The crystal structure can be described us a succession of infinite corrugated layers parallel to ab plane. These layers consist of rings formed by four sulfonate molecules located around a center of symmetry. The rings are connected to each other and to water molecules via O-H...O hydrogen bonds. The structure is further stabilized by π-π interactions between phenyl rings of organic entities of successive layers.  相似文献   

4.
The crystal structure of p-carboxyphenylhydrazone benzoylacetone is determined. The crystals are monoclinic, a = 13.614(4) Å, b = 11.388(2) Å, c = 20.029(6) Å, β = 104.82(2)°, V = 2339(9) Å3, Z = 8, space group C2/c, and R = 0.038 for 1622 reflections with I > 2σ(I). The crystal is built of C17H14N2O4 neutral molecules that are linked by O-H?O hydrogen bonds between the carboxyl groups into centrosymmetric pseudodimers. The effect of carboxylation of the phenylhydrazone fragment and the position of the carboxyl group on the molecular packing in the crystal is determined. The N(1)-H(1N)?O(1) intramolecular hydrogen bond (N-H, 0.94 Å; H?O, 1.87 Å; N?O, 2.59 Å; and the N-H?O angle, 133°) is formed in the molecule.  相似文献   

5.
The crystal structure of 11,12-epoxydrim-8(9)-en-11β-ol-7-one is determined by X-ray diffraction. The crystal data for the C15H22O3 composition are as follows: a = 6.646(1) Å, b = 7.242(1) Å, c = 7.635(2) Å, α = 84.34(3)°, β = 84.50(3)°, γ = 69.84(3)°, space group P1, and Z = 1. The structure is solved by the direct method and refined in the anisotropic approximation to R = 0.043 and R w = 0.110. The stereochemical formula of the compound is determined. It is shown that the hydroxyl group at the C(11) atom is situated at the β position. In the crystal, the molecules related by the translation along the a-b direction of the unit cell are linked into infinite chains by intermolecular hydrogen bonds between the hydrohyl group and the carbonyl oxygen atom [O-H?O, 2.867(4) Å].  相似文献   

6.
The crystal structure of 3β-hydroxy-4-(1,4-oxazin-4-yl)-androstane (C31H54NO2) has been determined by X-ray crystallographic techniques. The compound crystallizes in the orthorhombic space group P21212 with the following unit-cell parameters: a = 7.124(1) Å, b = 10.127(1) Å, c = 40.660(1) Å, V = 2933.4(1) Å3, and Z = 4. The structure has been solved by direct methods and refined to an R factor of 0.067. Three six-membered rings, A, C, and E, exist in the chair conformation, while the ring B adopts a distorted half-chair conformation. The five-membered ring, D, has a distorted envelope conformation. The crystal structure is stabilized by strong intermolecular O-H...O hydrogen bonds.  相似文献   

7.
The crystal structure of 2-hydroxy-3-trifluoracetylimidazo[1,2-a]pyridine hydrochloride C9H6F3ClN2O2 is determined by X-ray diffraction at 180 K. The structure is solved by the direct method and refined by the least-squares procedure to R = 0.0296. The alternation of bond lengths in the six-membered fragment of the molecule is observed. One of the specific features of the crystal structure is the formation of a system of the N-H?Cl? (N?Cl, 3.09 Å; N-H, 0.83 Å; H?Cl, 2.33 Å; and N-H?Cl, 153°) and O-H?Cl? (O?Cl, 2.87 Å; O-H, 0.95 Å; H?Cl, 1.92 Å; and O-H?Cl, 178°) hydrogen bonds in which the chlorine atoms are related to the reference atom by different symmetry transformations.  相似文献   

8.
The crystal structure of 2,3H-2-methyl-4-(4-nitrophenyl)-5-oxobenzopyrano[3,4-e]dihydropyran-2-ol is investigated using X-ray diffraction. The unit cell contains an ethanol molecule that forms hydrogen bonds with O-H and C-O groups of two molecules of the main compound and acts as a proton donor and a proton acceptor in these hydrogen bonds. Owing to these interactions, infinite chains are formed in the crystal. The crystallographic data for the structure of C19H15NO6·C2H5OH (M = 399.39) are as follows: the crystals are triclinic, space group P1, a = 5.5340(3) Å, b = 8.0109(4) Å, c = 11.0112(5) Å, α = 88.773(2)°, β = 84.788(2)°, γ = 79.958(2)°, and Z = 1.  相似文献   

9.
The crystal structure of the title compound contains eight molecules per asymmetric crystal unit, each four of the two enantiomers (Pa, a = 19.7547(3) Å, b = 17.2606(2) Å, c = 20.8149(4) Å, β = 114.2656(16)°, V = 6470.4(2) Å3, Z = 16). The independent molecules have significantly different conformations, and local pseudosymmetries are obeyed only very roughly. The oxime groups form the typical hydrogen bonded cyclic dimers, whereas the amine donors are not satisfied by any kind of hydrogen bonds.  相似文献   

10.
Dichloropicric acid is orthorhombic, space groupP212121; at 24°a=5.672(3),b=8.044(3),c=22.491(7) Å,D x=1.929(2) g-cm?3,V=1026(1) Å3,Z=4. The phenolic OH group is intramolecularly hydrogen bonded to one of theortho nitro groups with an O...O distance of 2.524(5) Å. As a consequence, this nitro group is twisted out of the plane of the benzene ring by only 20.1° in spite of crowding by the adjacent chlorine atom which is only 2.764(3) Å from the O atom in the nitro group. The two non-hydrogen bonded nitro groups have twist angles of 73.9 and 84.1°. There is no evidence of intermolecular hydrogen bonding with any adjacent dichloropicric acid molecule.  相似文献   

11.
A new organic compound with the formula C39H46Cl2N6O was synthesized from aqueous solution of 4,4′-diaminodiphenylmethane and hydrochloric acid at room temperature. This compound crystallizes in the monoclinic space group C2: a = 25.6525(16), b = 5.7107(3), c = 13.7777(8) Å, β = 118.862(2)°, V = 1767.64(22) Å3 and Z = 2, giving D x = 1.288 g cm?3. The refinement converged to R 1 = 0.027 and wR 2 = 0.0649. The structural arrangement can be described as infinite layers parallel to bc plane. In these layers cations and non protonated molecules are linked with N-H...N hydrogen bonds building [C39H44N6]2+ organic clusters. These clusters, in turn, are linked by N-H...Cl and O-H...Cl hydrogen bonds.  相似文献   

12.
A novel two-dimensional coordination polymer [Ag(μ3-hexamethylenetetramine)(H2O)](BF4) was synthesized and characterized by X-ray crystallography. It crystallized in the orthorhombic space group Pnnm with a = 15.561(7) Å, b = 10.754(5) Å, c = 6.514(3) Å, and Z = 4. Each Ag center is four-coordinated in a slightly distorted tetrahedral geometry. The structure consists of 2D wavy layers of hexagonal units; these 2D layers are further connected to form a 3D network by O-H⋯F, C-H⋯F hydrogen bonds with counter anions BF 4 in the layers. From Kristallografiya, Vol. 50, No. 4, 2005, pp. 648–650. Original English Text Copyright ? 2005 by Kong, Zhang, Sun, Okamura, Ueyama. The text was submitted by the authors in English.  相似文献   

13.
The crystal structures of two terpene derivatives, 2,4,5,6,7,7a-hexahydro-7a-hydroxy-3,6-dimethyl-2-benzofuranone (compound I) and β-cyclolavandulic acid (compound II), were determined by single-crystal diffractometry. Compound I, C10H14O3, crystallizes in the orthorhombic space group P212121 with the unit cell parameters a = 6.715(1) Å, b = 7.043(1) Å, c = 20.292(3) Å, and Z = 4. The six-membered ring has an ideal chair conformation. The five-membered ring is planar. Compound II, C10H16O2, crystallizes in the monoclinic space group P21/n with the unit cell parameters a = 8.446(1) Å, b = 12.156(1) Å, c = 9.901(1) Å, β = 106.29(1)°, and Z = 4. The cyclohexene ring exhibits a half-chair conformation. Both the crystal structures are stabilized by intermolecular O-H?O hydrogen bonds.  相似文献   

14.
The crystal and molecular structures of diphenyl sulphone (A), 4,4′-difluorodiphenyl sulphone (B) and 3,3′-dinitro-4,4′-difluorodiphenyl sulphone (C) have been determined from three-dimensional MoKα diffractometer data. Each molecule crystallizes in the monoclinic space groupP21/c with cell dimensionsa = 12.225(4),b = 7.830(2),c = 11.328(2) Å, β = 98 °19′(2);a = 8.255(3),b= 13.062(3),c = 10.135(2) Å, β = 99 ° 31′(2) anda = 14.736 (4),b = 8.145(2),c= 14.626(3) Å, β= 129°8′(2), respectively. The structures were solved by Patterson and Fourier techniques and refined by the method of least squares toR-factors of 3.8% over 1798 reflections, 6.3% over 1834 reflections and 5.4% over 2185 reflections forA,B andC, respectively. The dimensions of the sulphone group are similar in each molecule; the S—C bond lengths range from 1.764(3) to 1.775(3) Å, and the S—O bond lengths from 1.432(3) to 1.439(3) Å. The dihedral angles between the aromatic rings and the S—S—C planes lie between 72,6 and 88.9 °, compared with the value of 90 ° predicted for maximum conjugation between the sulphone group and the aromatic ring. Intermolecular H―O contacts of 2.37 Å suggest possible C—H—O type hydrogen bonds joining the molecules of 4,4′-difluorodiphenyl sulphone into dimers and the molecules of 3,3′-dinitro-4,4′-difluorodiphenyl sulphone into chains.  相似文献   

15.
The crystal structure of title compound (Fe[(C25H21N7O4S2)] · 4(C3NOH7), where C3NOH7 is dimethylformamide, DMF) was determined by the X-ray diffraction method. This compound crystallizes in the monoclinic C2/c space group, Z = 4. Unit cell parameters are: a = 13.6080(5), b = 17.6375(7), c = 19.5571(6) Å, β = 108.753(2)°. The N-H...O and O-H...O interactions stabilize the molecules in the lattice. The structure contains also the solvent dimethylformamide molecules, which are connected with intermoleculer hydrogen bond. The O atoms of DMF molecules take place as acceptor atoms.  相似文献   

16.
The crystal structure of 2-(2′-tosylamino-5′-nitrophenyl)-4H-3,1-benzoxazin-4-one (I) is studied by X-ray diffraction at 100 K (C21H15N3O6S, a = 20.899(2) Å, b = 10.948(1) Å, c = 8.260(1) Å, V = 1889.3(1) Å3, Z = 4, and space group Pbn21). The compound exhibits an anomalous Stokes shift. Upon cooling, the oxazineaminophenyl fragment of compound I acquires a quinoid structure and the linear parameters of the intramolecular N-H?N hydrogen bond increase (the distance between the heterocyclic nitrogen atom and the hydrogen atom of the tosylamino group becomes 1.92 Å). The complete optimization of the geometry of molecules in compound I and unsubstituted 2-(2′-tosylaminophenyl)-4H-3,1-benzoxazin-4-one in the ground singlet electronic state is performed by the semiempirical method with the MOPAC program. It is shown that the oxygen atoms in the sulfo group of molecule I are nonequivalent, because one of them is involved in the intermolecular C-H?O hydrogen bond.  相似文献   

17.
The crystal structures of two host-guest molecular complexes of 18-crown-6 with 2-aminobenzoic acid hydrazide monohydrate (the ratio host: guest: H2O = 1: 2: 2) (complex I) and 5-amino-1-benzyl-1,2,3-triazole-4-carboxylic acid hydrazide (the host: guest ratio = 1: 2) (complex II) are determined by X-ray diffraction analysis. Crystals I are monoclinic, a = 8.468(2) Å, b = 17.378(3) Å, c = 10.517(2) Å, β = 96.88(3)°, space group P21/n, and R = 0.0393 for 6692 reflections. Crystals II are orthorhombic, a = 18.489(1) Å, b = 10.192(3) Å, c = 20.412(2) Å, space group Pbca, and R = 0.0540 for 3513 reflections. In both complexes, the centrosymmetric 18-crown-6 and guest molecules are joined together through the NH?O (crown) hydrogen bonds, which involve all the hydrogen atoms of the hydrazine group. The NH?O=C intramolecular hydrogen bond is observed in the guest molecule. In structure I, the water molecule serves as a bridge between the guest molecules related by the glide-reflection plane and combines the guest-host-guest complexes into layers. In structure II, the guest molecules are linked into chains through hydrogen bonds of the NH?O=C type; in turn, the chains composed of guest molecules and the crown ether molecules bonded to these chains form a layered structure.  相似文献   

18.
The crystal structure of 2-amino-5-benzoyl-4-(2-nitrophenyl)-3-cyano-4,5-dihydrothiophene is determined by X-ray diffraction analysis. The unit cell parameters are as follows: a = 10.878(2) Å, b = 12.890(3) Å, c = 13.539(4) Å, α = 108.15(2)°, β = 99.26(2)°, γ = 107.13(2)°, V = 1656(2) Å3, d calcd = 1.410 g/cm3, Z = 4, and space group P1ˉ. The molecules occupy two systems of independent positions in the crystal. Similar to the compounds studied earlier in this series, the o-nitrophenyl substituent has a synperiplanar orientation relative to the hydrogen atom at the C(4) atom of the heterocycle. __________ Translated from Kristallografiya, Vol. 45, No. 2, 2000, pp. 282–285. Original Russian Text Copyright ? 2000 by Nesterov, Kuleshova, Samet, Shestopalov.  相似文献   

19.
The synthesis, variable temperature NMR spectra, and crystal structures of two crystalline forms, 2a and 2b, of the enamine 1-(N,N-diethylamino)-2,2-bis(2-nitrophenylthio)ethene have been obtained. Both forms crystallize in the monoclinic space group P21/a. The two phases have similar molecular structures but possess different intermolecular C–H······O hydrogen bonding interactions. Both forms exhibit disorder within the NEt2 fragment at 298 K: sufficient disorder persisted with 2a (orange needles) down to 100 K to make the geometric parameters pertaining to the enamine fragment unreliable. The disorder was effectively eliminated on cooling 2b down (red colored blocks) to 150 K. Cell dimensions for the 2a-phase are at 100 K: a = 11.1030(4) Å, b = 15.1325(7) Å, c = 12.4504(7) Å, β = 114.606(3)°, while for the 2b-phase at 150 K, a = 15.5206(4) Å, b = 7.6958(2) Å, c = 15.7137(3) Å, β = 92.580(7)°. The C–N bond length in the β-form at 150 K of 1.335(3) Å indicates considerable double bond character: the rotational barrier of the C–N bond in CDCl3 was calculated to be 52.4 kJ mol?1.  相似文献   

20.
The crystal structure of 1,3-dinitro-4,6-di[3-(2,2,5,5-tetramethyl)pyrrolidinyl-N-oxide] aminobenzene monohydrate has been determined by single-crystal X-ray diffraction methods using the 1793 unique reflections for which 3 ° < 2θ < 40 ° andI > 3σ(I), and refined to a conventionalR index of 0.032. Counter methods using MoKα radiation were employed. Crystals form in the triclinic space groupP¯1 (No. 2) witha = 16.160(10),b = 11.686(6),c = 7.211(5) Å, α = 95.87(5) °, β = 98.67(5) °, and γ = 107.74(4) °. All hydrogen atom positions were determined. Intramolecular hydrogen-bonding between the nitro and amino groups has, in part, caused the central 20 atoms of the molecule, counting hydrogen atoms, to lie in an approximate plane. The benzene ring is distorted by its substituents to the symmetrymm2(C 2v ). The internal angles of the benzene ring range from 116.1 ° to 124.7 ° (esd = 0.3 °), and its bonds are between 1.368 Å and 1.436 Å (esd = 0.004 Å) in length. Four of the five atoms in each pyrrolidine ring are nearly coplanar; the remaining atom, the carbon bonded to the amine nitrogen in each case, lies approximately 0.53 Å from the corresponding plane. The best four-atom planes of the two pyrrolidine rings are each near to perpendicular to the central plane, giving the molecule a lobster-like appearance; they are each rotated approximately 15 °, in opposite senses, from perpendicular. The intramolecular distance between the two pyrrolidine nitrogen atoms, to which the unpaired charges can be assigned, is 7.68 Å. One of the nitroso oxygen atoms is hydrogen-bonded by two symmetry-equivalent water molecules. The inversion center necessitates that the remaining hydrogen atoms of these water molecules both hydrogen-bond to a symmetry-equivalent nitroso oxygen atom to give a hydrogen-bonded four-oxygen ring.  相似文献   

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