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1.
The crystal structure of 3, 3-diphenylnaphtho[1, 2-c]furan-1(3H)-one 2 was determined by X-ray diffraction analysis. It possesses P212121 (#19) space group symmetry, with a = 11.922(2), b = 17.142(4), c = 8.429(2) Å, and D calc = 1.297 mg/m3 for Z = 4.  相似文献   

2.
3.
X-ray diffraction data are presented for the title mesoionic compound (I), its hydrochloride salt (II) and methylated derivative (III). The crystal of (I) is orthorombic, space group P212121, with cell dimensions: a = 5.857(1) Å, b = 12.494(2) Å, c = 16.328(3) Å, with four molecules per unit cell. The crystal of (II) is monoclinic, space group P21/n, with cell dimensions: a = 5.5720(10) Å, b = 21.5770(4) Å, c = 11.2330(2) Å, beta = 95.15(3)°, with four molecules per unit cell. The crystal of (III) is monoclinic, space group P21/n, with cell dimensions: a = 12.0886(5) Å, b = 7.9103(4), c = 104.29(1) Å, beta = 104.29(1)°, with four molecules per unit cell. Of particular interest is the fact that the C5–N6 bond appears to have a high double bond character in all three of the compounds studied. In addition, it is found that the exocyclic N-phenyl group changes from being in the cis conformation with respect to sulfur in compounds (I) and (III) to the trans conformation in the hydrochloric salt (II).  相似文献   

4.
Eight sesquiterpene lactones, two coumarins, and two flavonoid derivatives were isolated from Tanacetum cadmeum (Boiss.) Heywood ssp. cadmeum. All compounds have been found previously in other plant species. The crystal structures of artesin and taurin are reported. Crystals of artesin (C15H22O3) belong to the monoclinic space group P21: a = 8.300(1), b = 6.304(1), c = 13.118(2) Å, = 101.836(3)°, V = 671.8(2), Z = 2, R 1 = 0.0291. Crystals of taurin belong to the monoclinic space group P21: a = 5.722(1), b = 8.279(2), c = 14.503(3) Å, = 90.025(1)° , V = 687.0(3), Z = 2, R 1 = 0.0493. An investigation of the space group indicated a monoclinic system rather than orthorhombic.  相似文献   

5.
The crystal structure of the 1:1 adduct hydrate of strychnine with 1,7-Cleve's acid (8-amino-2-naphthalenesulfonic acid), namely strychnine-8-ammonio-2-naphthalenesulfonate-water (1/1/3.5) has been determined and provides a unique example of a neutral association involving strychnine and an achiral zwitterionic acid species, previously unobserved in the structures of either strychnine or brucine addition compounds. Crystals are orthorhombic, space group P212121, with Z=4 in a cell with dimensions a=10.4484(8), b=30.850(3), c=9.4998(11) ?. Hydrogen bonding involving all available proton-donor and acceptor sites on all species gives rise to a three-dimensional framework polymer structure. The crystallographic literature for strychnine and brucine and their compounds is also reviewed.  相似文献   

6.
Three adducts SF4·BF3, SF4·AsF5, and SF4·SbF5 were studied in this work, in gas phase, DFT method was performed to study their molecular structures and thermodynamic properties. The heat of formation was studied at the high level DFT levels.

Crystal structures were predicted using the Dreiding force field and refined by DFT-GGA-RPBE method. All the obtained crystal structures belong to the P21/c space group. The lattice energies were predicted to be located between ?91.86 and ?693.73 kJ/mol at the GGA-RPBE level. Based on the optimized crystal structures, the band gap (ΔEg) and density of state (DOS) were predicted and the calculations indicate that they are semiconductors with the band gap between 2.22 and 2.43 ev.  相似文献   

7.
Abstract

Four novel anthracene-based chalcone derivatives, (E)-1-(anthracen-9-yl)-3-(4-nitrophenyl)prop-2-en-1-one 1, (E)-1-(anthracen-9-yl)-3-(3-chlorophenyl)prop-2-en-1-one 2, (E)-1-(anthracen-9-yl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one 3, and (E)-1-(anthracen-9-yl)-3-(pyridin-4-yl)prop-2-en-1-one four were synthesized and their structures were solved by single crystal X-ray diffraction methods. The anthracenyl chalcone 1 crystallizes in the centrosymmetric monoclinic P21/c space group. The crystal structure analysis shows that the molecules of one form two dimensional (2D) corrugated layer structure. The anthracenyl chalcone 2 crystallizes in the centrosymmetric triclinic P-1 space group and forms one dimensional (1D) tape like structure in the crystal. Compound 3 crystallizes in the centrosymmetric monoclinic P21/n space group. Anthracenyl chalcone 4 crystallizes in the centrosymmetric triclinic P-1 space group.  相似文献   

8.
The title compound 14-hydroxy-14-phenyldibenzo[a,j]xanthene 1 formed a (1:1) complex with diethyl ether. 1,4-Dioxane was also enclathrated, but with a variable stoichiometric ratio. Single crystal X-ray crystallography was used to elucidate the crystal structure of the 1·diethyl ether complex. Crystals are orthorhombic with space group P212121, a = 8.532(3), b = 15.040(4), c = 18.491(5) Å, V = 2373(1) Å3, d c = 1.256 g/cm3, and Z = 4. Host and guest molecules were found to associate via hydrogen bonds, with the guest molecules residing in undulating channels lined by host molecules.  相似文献   

9.
The molecular and crystal structure of the title compound2, prepared in racemic form by addition of phenylmagnesium bromide to 6-exo-methyl-6-endo-nitrobicyclo[2.2.1]heptan-2-one (1) in the presence of cerium(III) chloride, were determined by single-crystal X-ray diffraction. The crystal selected for analysis was found to belong to the chiral orthorhombic space group P212121, witha=6.685(3),b=10.0788(5),c=18.581(1) Å. In the crystal, molecules of2 are associated by intermolecular hydrogen bonds between hydroxy and nitro groups (OH...O2N=0.82 Å).Nitrobicyclo[2. 2. 1]heptanes. Part 10. Part 9: Michael, Maqutu and Denner (1991).  相似文献   

10.
Single crystals of Ca2FeO3Cl have been obtained as a by product during single crystal growth experiments of calcium ferrates from a CaCl2 flux. The reddish‐brown optically uni‐axial crystals adopt the tetragonal space group P4/nmm with a = 3.8381(4) Å and c = 13.685(2) Å and Z = 2 formula units per cell. The structure has been determined from a single crystal diffraction data set collected at room conditions and refined to final residual R(|F|) = 0.053 for 163 observed independent reflections with I > 2σ(I). Ca2FeO3Cl belongs to the structure family of the Ruddlesden‐Popper series with n = 1, which is also referred to as the K2NiF4‐type. Main building units are layers of perovskite type corner connected FeO5Cl‐octahedra perpendicular to [001]. The two crystallographically independent calcium ions are located between the octahedral layers and are coordinated by nine ligands each: Ca1 (4×O + 5×Cl) and Ca2 (9×O). Following prior studies Ca2FeO3Cl crystallizes in space group P4. However, the present investigation shows clearly that this assignment is incorrect and that the compound has been described in an unnecessarily low symmetry.  相似文献   

11.
The crystal and molecular structure of 5-(4-ethylcyclohexyl)-2-(4-cyanophenyl)pyrimidine (ECCPP), C19H18N3, has been determined at room temperature by means of direct methods. The crystals belong to the monoclinic space group P21/n, a = 15.959(2), b = 33.469(3), c = 6.210(3) Å β = 90.335(7)° with 8 molecules in the unit cell. Refinement converged to an R value of 0.086. One of the two independent molecules in the unit cell exhibits disorder in the cyclohexane ring. The molecules extend roughly in the [010] direction and form a rather complicated structure in which dipolar interactions play a role.  相似文献   

12.
The complex [Y(NO3)3(OH2)3]·(Me2-16-crown-5)·H2O has been prepared and its crystal and molecular structure determined using single crystal X-ray diffraction. The colorless crystals belong to the monoclinic space group P21/n with Z = 4. Lattice parameters are a = 10.420(1), b = 17.257(3), c = 14.646(2) Å, = 96.79(1)°, V = 2615.1(6) Å3. The yttrium(III) ion is nine-coordinate, bonded to three bidentate nitrate groups and three water molecules. The average Y–O(nitrate) and Y–O(water) distances are 2.42(3) and 2.33(1) Å, respectively. The average HO–H···O hydrogen bonded separation is 2.767Å.  相似文献   

13.
A new organic UV nonlinear optical crystal urea-(DL)tartaric acid [CO(NH2)2−(DL) C4H6O6] (abbreviated as U(DL)T) is reported. Large single crystals have been grown from aqueous solution by the cooling method. They belong to the monoclinic space group P21 and the lattice parameters are: a = 7.6973 Å, b = 23.3310 Å, c = 4.8727 Å, and β = 100.82°. The structure and some of its physical properties have been determined. The crystal is transparent from 0.24 to 1.95 μm. The efficiency of powder SHG is larger by one order of magnitude than that of KDP. Thus the crystal will be a useful NLO material.  相似文献   

14.

Abstract  

The crystal structure of 2-(2,2-dibromovinyl)-1-methyl-1H-imidazole-4,5-dicarbonitrile (C8H4Br2N4, Mr = 315.92) has been determined by single crystal X-ray diffraction analysis. The compound crystallizes in the monoclinic crystal system with space group P21/c and unit cell parameters: a = 15.144(2), b = 16.382(3), c = 8.267(1) ?, β = 95.76(2)o and Z = 8. The final reliability index is 0.0297 for 2505 observed reflections. The two molecules of 2-(2,2-dibromovinyl)-4,5-dicyano-1-methylimidazole are localized in independent part of unit cell. The crystal packing is stabilized by C–H···N hydrogen bonds and Br···N intermolecular interactions.  相似文献   

15.
The Schiff base compounds, isonicotinic acid [1-(3-methoxy-2-hydroxyphenyl) methylidene]hydrazide (C14H13N3O3, 1) and isonicotinic acid [1-(4-dimethylaminophenyl) methylidene]hydrazide monohydrate (C15H16N4O·H2O, 2) have been synthesized by the condensation of equimolar 3-methoxysalicylaldehyde or 4-dimethylaminobenzaldehyde with isonicotinic acid hydrazide in MeOH or EtOH. The compounds were characterized by elemental analysis, IR, 1HNMR spectra, and single crystal X-ray diffractions. Compound 1 crystallizes in the monoclinic space group P-1 with unit cell dimensions a = 7.662(1) ?, b = 16.249(2) , c = 10.874(2) ?, β = 110.426(3)°, V = 1268.7(3) ′3, Z = 4, R 1 = 0.0644, and wR 2 = 0.1283. Compound 2 crystallizes in the orthorhombic space group P212121 with unit cell dimensions a = 7.388(1) ?, b = 11.812(1) ?, c = 17.197(2) ?, V = 1500.7(2) ′3, Z = 4, R 1 = 0.0585, and wR 2 = 0.1143. X-ray structure determinations revealed that the molecules of both compounds display trans configurations with respect to the C=N double bonds. In the crystal structure of 1, molecules are linked through N–H···N intermolecular hydrogen bonds, forming layers parallel to the bc plane, while in the crystal structure of 2, molecules are linked through N–H···O, O–H···O, and O–H···N intermolecular hydrogen bonds, forming a network. Supplementary material CCDC-615072 and 620235 contain the supplementary crystallographic data for this paper. These data can be obtained free of charge at http://www.ccdccam. ac.uk/const/retrieving.html or from the Cambridge Crystallographic Data Centre (CCDC), 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44(0)1223–336033 or e-mail: deposit@ccdc.cam.ac.uk.  相似文献   

16.
The molecular packing in p-hydroxy-cinnamic acid has been determined by single-crystal x-ray analysis in order to establish the role played by hydrogen bonding in inhibiting mesophase formation. The molecules exist in the crystal as centrosymmetric hydrogen-bonded dimers whose long axes are inclined at ± 84.7° to the crystal b-axis and lie almost in the (104) crystal planes. Rows of dimers lying parallel to b are linked into infinite sheets coincident with the (104) planes by head-to-tail hydrogen bonds involving the phenolic –OH groups. These sheets are interlocked by the alternating ring orientations of neighboring molecules in adjacent sheets.

Crystals belong to the monoclinic system, space group P21/c, with a = 8.707(3), b = 5.256(2), c = 17.207(6) Å, β = 99.67(2)°, and Z = 4. The structure was solved by direct methods, and least-squares refinement gave R = 0.057 for 800 independent reflections whose intensities were measured by counter diffractometry.  相似文献   

17.
The crystal structure of 1-phenyl-3-methyl-4-(salicylaldehyde hydrazone)-propenylidene-5-pyrazolone (PMPP-SH) was characterized by the single-crystal X-ray diffraction method. The cell parameters of PMPP-SH in the monoclinic P21/c space group are a = 10.851(1) Å, b = 11.679 (1) Å, c = 14.043 (2) Å and β = 91.89 (1). Analyzing the molecular structure suggest that, in the solid state, the title compound exists mainly in enaminopyrazolone form, which is stabilized by intramolecular hydrogen bonding, rather than NH-form.  相似文献   

18.
The X-ray crystal structure of 3-mesityl-1,4-benzoquinonemonoxime is described. The structure reveals that hydrogen-bonds are formed between the oxime and keto groups to form one-dimensional hydrogen bonded ribbons. The structure (C15H15NO2) is orthorhombic with a = 8.9098(7), b = 10.6399(8), c = 13.7086(10) Å and space group P212121.  相似文献   

19.
Crystals of the hydrobromide of the alkaloid designated porantheridine, C15H27NO, isolated from the plantPoranthera corymbosa Brogn. (family Euphorbiacaea), belong to the space groupP212121, with cell dimensionsa= 10·059,b = 16·704 andc = 9·629 Å. The crystal structure was solved by the heavy-atom method and refined with 624 reflexions to a residual of 0·078. The molecule consists of three six-membered rings fused on to a common central nitrogen atom; one ring contains an oxygen atom with ann-propyl group and a methyl group substituted on the vicinal carbon atoms. The rings have thechair conformation, two being fusedtrans to each other andcis to the third. The absolute configuration was determined using the anomalous scattering power of the bromine atom.  相似文献   

20.
7,9-dideacetyl-1-deoxybaccatinVI was synthesized from 1-deoxybaccatinVI and its crystal structure was determined by X-ray crystallographic techniques. The compound (C33H42O11·2CH4O) crystallizes into monoclinic space group P21 with unit cell parameters: a=8.654(17) ?, b=16.470(5) ?, c=12.671(3) ?, β=97.63(2)°, and Z=2. The X-ray results demonstrated that the reaction of 7,9,10-Trideacetyl-1-deoxy-baccatinVI with Ac2O in tetrahydrofuran, using CeCl3 as catalyst, yielded monoacetylated product 7,9-dideacetyl-1-deoxy baccatinVI. In the structure, the six-membered A ring exhibits boat conformation, the eight-membered B ring adopts boat-chair conformation, and the six-membered C ring exhibits sofa conformation.  相似文献   

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