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1.
The crystal structure of (E)-2-[(2-Bromophenylimino)methyl]-5-methoxyphenol is determined by using X-ray diffraction and then the molecular structure is investigated with density functional theory (DFT). X-Ray study shows that the title compound has a strong intramolecular O-H…N hydrogen bond and three dimensional crystal structure is primarily determined by C-H…π and weak van der Waals interactions. The strong O-H…N bond is an evidence of the preference for the phenol-imine tautomeric form in the solid state. Optimized molecular geometry is calculated with DFT at the B3LYP/6-31G(d,p) level. The IR spectra of compound were recorded experimentally and calculated to compare with each other. The results from both experiment and theoretical calculations are compared in this study.  相似文献   

2.

Abstract  

1-(2-Chlorobenzyl)-2-methylthio-1H-benzimidazole compound has been synthesized and characterized by elemental analysis, IR and 1H-NMR spectroscopy and single crystal X-ray diffraction. The compound crystallizes in the triclinic space group P-1 with unit cell parameters a = 17.201 ?, b = 5.873 ?, c = 24.791 ?, α = 67.410(10)°, β = 74.083(11)°, γ = 81.858(12)°. In the crystal packing, no classic hydrogen bonds are founded, but C–H···π interactions are being between the molecules. The molecular geometry and vibrational frequencies of (C15H13ClN2S) in the ground state have been calculated by using Hartree–Fock (HF) and Density Functional Method (DFT/B3LYP) with 6-31G(d) basis set. The optimized geometric bond lengths and bond angles obtained by using HF and DFT (B3LYP) show the best agreement with the experimental data.  相似文献   

3.
  The molecular and crystal structures of the title compound, C22H16N4O2, were determined by single crystal X-ray diffraction technique. The title compound crystallizes in monoclinic space group P1 2 1 /n1, with a=12.7811(9) ?, b=8.2002(4) ?, c=17.8772(14) ?, Z=4, D calc=1.3112(1) g/cm3, μ (Mo-Kα)=0.087 mm−1. The structure was solved by direct methods and refined to a final R=0.056 for 1891 reflections with I > 2σ (I). The asymmetric unit in the crystal structure contains only one neutral molecule. The positions of nitrogen atoms in the azo groups were disordered. There is no classic hydrogen bond in the crystal structure. The molecules in the crystal structure are stacked by π–π stacking and one edge-to-face interactions. In order to determine conformational flexibility and crystal packing effects on the molecules, molecular energy profile of the title compound was obtained with respect to the selected torsion angle, which is varied from −180° to +180° in every 10° via PM3 semi-empirical method.  相似文献   

4.

Abstract  

A new compound of (C27H25N3S) has been synthesized and characterized by 1H NMR, 13C NMR, IR, UV-Visible spectroscopy, and single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/c and crystals of (I) were found approximately 0.5:0.5 ratio to be twinned. The crystal structure is stabilized by N–H···N inter molecular hydrogen bonding. In addition to the molecular geometry and dimeric structure from X-ray experiment, the optimized molecular geometry for monomer and dimer, vibrational frequencies, atomic charges distribution, and total energies of the title compound in the ground state have been calculated using ab initio method. Density Functional Theory (B3LYP) and Hartree-Fock (HF) methods with basis sets 6-31G(d, p) and 3-21G were used in the calculations. Calculated frequencies are in good agreement with the corresponding experimental data. UV-Vis absorption spectra of the compound have been ascribed to their corresponding molecular structure and electrons orbital transitions.  相似文献   

5.
Abstract  The title compound, [Cu(C3H4N2)4(COO–(CH2)4–COOH)2] is a neutral complex and exist as a monomeric unit. The Cu atom occupies at the center of symmetry (0, 0.5, 0) with a distorted octahedral geometry. Imidazole nitrogens N1 and N6 (Cu1–N1 = 1.993(3) ?; Cu1–N6 = 2.008(3) ?) from two different imidazole group which are symmetrically disposed provides the square base and the long carboxylate oxygens (Cu1–O2 = 2.582(3) ?) from the protonated end of symmetrically oriented dibasic acid at the trans axial position. The adipate monoanion is in weak coordination with the metal center via monodentate fashion. The strong carboxylate-carboxylic acid intermolecular O–H…O interaction between the adjacent molecules is present in this structure as observed in the crystal structure of hexanedioic acid is noteworthy. In addition to the O–H…O H-bonding other molecular interactions such as N–H…O and C–H…O in packing generates a 3-D hydrogen bond network. Graphical Abstract  The title compound tetrakis imidazole Cu(II) diadipate is a neutral complex and exist as a monomeric unit with the metal atom occupies at the center of symmetry. Strong inter and intramolecular H-bonding interactions such as O–H…O, N–H…O and C–H…O in packing generates a 3-D hydrogen bond network.  相似文献   

6.
The titled compound (1), has been synthesized and characterized by IR and 1H-NMR spectroscopy, and single crystal X-ray diffraction. The compound crystallizes in the triclinic space group P-1. The crystal structure is stabilized by C-H…π and aromatic π-π interactions. There are also intramolecular N-H…N and C-H…N hydrogen bonds in the molecule. The use of quantum chemical calculations to characterise and optimise the choice of material is illustrated by ab initio treatments. Vibrational frequencies and LUMO-HOMO energy difference of 1 have also been investigated by Density functional theory (DFT) and Hartree-Fock (HF) calculations. Calculated frequencies are in good agreement with the corresponding experimental data.  相似文献   

7.
The title molecule, (Z)-2-(1H-imidazol-1-yl)-1-(3-methyl-3-mesitylcyclo-butyl)ethanone oxime (C19 H25 N3 O), was prepared and characterized by1H-Nuclear magnetic resonance (NMR), 13C-NMR, infrared spectroscopic methods, and X-ray single-crystal determination. The compound crystallizes in the orthorhombic space group P c c n with a = 31.4660(17) Å, b = 11.2140(7) Å, and c = 10.0710(8) Å. In addition to molecular geometry from X-ray determination, vibrational frequencies and gauge, including atomic orbital, 1H- and 13C-NMR chemical shift values of the title compound in the ground state, were calculated using the density functional method with the 6-31G(d) basis set. The calculated results show that the optimized geometries can well reproduce the crystal structure. Besides, the theoretical vibrational frequencies and chemical shift values show good agreement with experimental values. The predicted nonlinear optical properties of the title compound are greater than those of urea. Density functional theory calculations of molecular electrostatic potentials, frontier molecular orbitals, and thermodynamic properties of the title compound were carried out at the B3LYP/6-31G(d) level of theory.  相似文献   

8.

Abstract  

The molecular and crystal structure of the title compound, C14H11Cl2NO, has been determined by X-ray single crystal diffraction technique. The compound crystallizes in the orthorhombic, space group Pbca with unit cell dimensions a = 7.5537(10) ?, b = 11.5518(13) ?, c = 29.760(4) ?, M r  = 280.14, V = 2596.8(6) ?3, Z = 8, R 1 = 0.065 and wR 2 = 0.191. The title compound exists in the enol–imine tautomeric form with a strong intramolecular O–H···N hydrogen bond. The dihedral angle between the two benzene rings is 37.66(15)°. The asymmetric unit in the crystal structure contains only one neutral molecule. Calculational studies were performed by using AM1, PM3, PM6 semi-empirical and DFT methods. Geometry optimizations of compound have been carried out by using three semi-empirical methods and DFT method and bond lengths, bond and torsion angles of title compound have been determined. Dipole moments (Debye) and the energy parameters of compound (kcal/mol) were calculated by using above mentioned calculation methods. Atomic charge distribution has been obtained from AM1, PM3, PM6 and DFT. In order to determine conformational flexibility on the molecule, molecular energy profile of the title compound was obtained with respect to the selected torsion angle T(N1–C7–C1–C2), which is varied from −180° to +180° in every 10 via PM3 semi-empirical method.  相似文献   

9.
The molecular and crystal structures of the title compound, C19H22N2O4S, were determined by single crystal X-ray diffraction technique. The title compound crystallizes in space group F d d 2, with a = 30.785(3) ?, b = 10.6455(9) ?, c = 11.0036(8) ?, Z = 8, D calc = 1.379(2) g cm−3, μ(Mo-Kα) = 0.207 mm−1, and its crystal system is orthorhombic. The structure was solved by direct methods and refined to a final R = 0.042 for 1530 reflections with I > 2σ (I). There is a half-independent molecule in the asymmetric unit. The title molecule has twofold rotational symmetry along with the C–S bond. Classically no hydrogen bond is found in the crystal structure. The crystal structure is stabilized by π–π stacking and edge to face (C–H…π-ring) interactions. To elucidate conformational features and steric hindrances of the title molecule, selected torsion angle is varied from −180° to +180° in every 10° and thus molecular energy profile is calculated by PM3 semi-empirical method.Supplementary materials CCDC 261789 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, by emailing data_request@ccdc.cam.ac.uk, or by contacting The Cambridge Crystallographic Data Centre, 12, Union Road, Cambridge CB2 1EZ, UK; fax: $+$44 1223 336033.  相似文献   

10.
Abstract  The crystal structure of C14H12ClNO2 was determined by X-ray analysis. It crystallizes in the triclinic space group Pc with a = 12.5346(10) ?, = 4.5101(3) ?, = 12.0534(11) ?, α = 90.00o, β = 113.669(6)o, γ = 90.00o, = 2, Dx = 1.393 mg/m3, μ (MoKα) = 0.298 mm−1. The title compound is photochromic and molecule is non-planar. It adopts a phenol–imine tautomeric form with a strong intramolecular O–H···N hydrogen bond and a strong intermolecular C–H···O hydrogen bond. Minimum energy conformations AM1 were calculated as a function of the three torsion angles θ1(C10–C9–N1–C8), θ2(C9–N1–C8–C1) and θ3(N1–C8–C1–C6), varied every 10°. As in the X-ray experiment results, molecule has an angle that makes it non-planar between two aromatic rings in AM1 optimized geometry. Graphical Abstract  Molecular and crystal structure of [(E)-2-[(3-chlorophenylimino)methy])-4-methoxyphenol], C14H12ClNO2, have been determined by single crystal X-ray diffraction study, and conformational analysis of the title molecule with respect to the selected torsion angle has been achieved by AM1 semi-empirical calculations.   相似文献   

11.

Abstract  

The title compound, C25H21BrN2O3, was synthesized and structurally characterized by elemental analysis, IR, MS, 1H NMR and single crystal X-ray diffraction. The crystal is of orthorhombic system, space group Pbca with a = 11.706(2) ?, b = 18.038(4) ?, c = 20.369(4) ?, α = 90.00°, β = 90.00°, γ = 90.00°, V = 4301.0(15) ?3, Z = 8, Dc = 1.474 g/cm3, F (000) = 1952.0, μ(MoKα) = 1.941 mm−1, the final R 1 = 0.0670 and wR 2 = 0.2319 for reflections with I > 2σ(I). The crystal structure is stabilized by un-classical hydrogen-bonding C–H···O forming a three-dimensional network. The optimized geometric bond lengths and bond angles obtained by using density functional theory have been compared with X-ray diffraction values. In addition, the preliminary biological test showed that the title compound had anti-Mycobacterium phlei 1180 activity.  相似文献   

12.
The title compound crystallizes in the monoclinic space group P21/c with unit cell parameters a = 15.6239(15) ?, b = 14.0537(14) ?, c = 5.8396(5) ?, β = 92.666(3)°, V = 1280.8 (2) ?3, and Z = 4. The final reliability index is 0.0538 for 2921 observed reflections. Two phenyl rings of the title molecule are not coplanar, with a dihedral angle of 46.3(0)°. The molecular planarity of this substituted chalcone is strongly affected by the 4′-bromo group. The crystal cohesion is accentuated by π···π, C–H···Br interactions and R3 1 (11) hydrogen bond.  相似文献   

13.
10-(2-Benzothiazolylazo)-9-phenanthrol (L) is prepared by a reaction of 2-hydrazinobenzothiazol with 9,10-phenanthrenequinone. The crystal and molecular structure of the L·CHCl3 solvate is determined by X-ray diffraction. The data of the X-ray diffraction study, as well as IR, 1H NMR, and electronic absorption spectra, indicate that in the crystal state and solutions the L molecule exists in the form of a quinohydrazone tautomer (b) (s-trans, cis) stabilized by the intramolecular N2-HN2…O1 hydrogen bond. The “mobile” H atom is located at the N2 atom of the azo group. The benzothiazolyl and phenanthrenequinone fragments are nearly coplanar. Spectroscopic criteria for the state of L in various media are determined based on the data of IR, 1H NMR, and electronic absorption spectroscopy and the results of the Pariser-Parr-Pople quantum-chemical calculations.  相似文献   

14.
Abstract  The title compound, C18H18BrN3O3S, a derivative of 1,3,4-oxadiazole, crystallizes in the triclinic space group P-1 with unit cell parameters a = 6.8731(3), b = 8.9994(4), c = 15.7099(6) ?, α = 92.779(3)°, β = 130.575(3)°, γ = 107.868(4)°, Z = 2. The dihedral angle between the mean planes of the planar naphthyl and morpholine (chair) rings with the planar oxadiazol ring is 50.1(8) and 76.8(6)°, respectively. The planar naphthyl ring is twisted 52.2(5)° with the mean plane of the morpholine ring. A group of four intermolecular close contacts are observed between a bromine atom and hydrogen atoms from the closely packed naphthyl, morpholine and oxy–methyl groups in the unit cell. These molecular interactions in concert with an additional series of π–π stacking interactions that occur between the center of gravity of the two 6-membered rings of the naphthalene group influence the twist angles of each of these three groups. A MOPAC AM1 calculation of the conformation energy of the crystal structure [226.0128(9) kcal] compared to that of the minimum energy structure after geometry optimization [29.9744(1) kcal] reveals a significantly reduced value. The twist angles of the three groups above also change after the AM1 calculation giving support to the influence of both intermolecular C–H···Br short-range interactions and Cg π–π stacking interactions on these angles which therefore play a role in stabilizing crystal packing. Graphical Abstract  Crystal structure of 5-{[(6-bromonaphthalen-2-yl)oxy]methyl}-3-(morpholin-4-ylmethyl)-1,3,4-oxadiazole-2(3H)-thione, C18H18BrN3O3S, is reported and its geometric and packing parameters described and compared to a MOPAC computational calculation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

15.
The crystal structure of 2-amino-3-cyano-4,6-dihydro-4-(3-nitrophenyl)-5H-pyrano[3,2-c]quinolin-5-one N,N-dimethylformamide solvate monohydrate is determined by room temperature X-ray diffraction. The title compound 1, C22H21N5O6, is triclinic, space group P-1, a=9.109(2) ?, b=11.340(2) ?, c=12.485(2) ?, α=70.02(1)°, β=69.36(1)°, γ=67.32(1)°, Z=2, V=1081.4(4) ?3. It is interesting that a bridge-like hydrogen bond O–H···O is formed between the title compound and solvent molecules of water with molecular ratio of 2:2 building a bi-layer framework. In addition, there are two other types of classical hydrogen bonds N–H···N and N–H···O in the crystal structure.Supplementary material Crystallographic data for the structure reported in this paper have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication no. CCDC-275001. Copies of available material can be obtained, free of charge, on application to the Director, 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 single crystal X-ray diffraction analysis of the title compound, C14H20N2O3, reveals that the structure is adapted to its zwitterionic form and centrosymmetric dimers are formed by N+–H···O type ionic weak hydrogen bonds in the crystal structure. The title compound crystallizes in the triclinic space group P−1 with a = 5.9255(13) ?, b = 9.853(3) ?, c = 12.248(3) ?, α = 101.793(19)°, β = 94.941(17)°, γ = 104.36(2)°, Z = 2, Dx = 1.308 g/cm3, μ (Mo-Kα) = 0.092 mm−1. The structure was solved by direct methods and refined to a final R = 0.0371 for 2183 reflections with I > 2σ (I). The crystal structure is stabilized by N+–H···O type intra-molecular hydrogen bonds and N+–H···O type packing interactions referred to as weak hydrogen bonds. To elucidate conformational flexibility of the title molecule, the selected torsion angle is varied from −180° to +180° in every 10° separately and then molecular energy profile is calculated and construed. In addition, charge-population analysis of the crystallographically observed structure confirms its zwitterionic form.  相似文献   

17.
Abstract  The title compound N-(2,3,4-trimethoxy-6-methylbenzylidene)-2-methyl-benzenamine (C18H21NO3, M r = 299.36) was synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/n, with a = 7.2804(5), b = 8.5909(9), c = 26.117(3) ?, β = 92.056(2)°, V = 1,632.4(3) ?3, Z = 4, D c = 1.218 g cm−3, λ = 0.71073 ?, μ(Mo ) = 0.083 mm−1, F(000) = 640. The final refinement gave R = 0.0497, wR(F 2) = 0.1157 for 2,879 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the dihedral angle between the two phenyl rings is 25.9 (2)°. The molecule adopts a trans configuration about the central C=N functional bond. The crystal structure is stabilized by C–H…O hydrogen bonds and ππ stacking interactions. The title compound possesses moderate antibacterial activity. Graphical Abstract  The title compound N-(2,3,4-trimethoxy-6-methylbenzylidene)-2-methyl-benzenamine (C18H21NO3, M r = 299.36) was synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/n, with a = 7.2804(5), b = 8.5909(9), c = 26.117(3) ?, β = 92.056(2)°, V = 1,632.4(3) ?3, Z = 4, D c = 1.218 g cm−3, λ = 0.71073 ?, μ(Mo ) = 0.083 mm−1, F(000) = 640. The final refinement gave R = 0.0497, wR(F 2) = 0.1157 for 2,879 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the dihedral angle between the two phenyl rings is 25.9 (2)°. The molecule adopts a trans configuration about the central C=N functional bond. The crystal structure is stabilized by C–H…O hydrogen bonds and ππ stacking interactions. The title compound possesses moderate antibacterial activity.   相似文献   

18.
The title compound 5-bromo-1-(2-cyano-pyridin-4-yl)-1H-indazole-3-carboxylic acid diethylamide, C18H16BrN5O, is prepared from 5-bromoindazole-3-carboxylic acid methylester. N 1-arylation is carried out with 4-chloro-2-cyanopyridine and the resulting product is converted to diethylamide by reacting with thionyl chloride and diethylamine. The structure is identified from its FT-IR, 1H NMR, 13C NMR spectroscopy, elemental analysis data and unambiguously confirmed by single crystal X-ray diffraction studies. There are two symmetry independent molecules in the asymmetric unit with no significant differences in bond lengths and angles. The title compound crystallizes in the triclinic system, space group \(P\bar 1\) , with a = 11.2330(2); b = 11.6130(2); c = 15.4710(3) Å, α = 92.515(1)°; β = 109.956(1)°; γ = 107.199(1)°; V = 1788.45(6)Å3 and z = 4. An intramolecular C-H…N hydrogen bond forms an S(6) ring motif in one of the unique molecules. In the crystal, two molecules are linked about a center of inversion by C-H…O hydrogen bonded dimers generating an R 2 2 (16) ring motif. The crystal packing is stabilized by C-H…N, C-H…O hydrogen bonds and π…π stacking interactions.  相似文献   

19.
The synthesis, spectroscopic studies and crystal structure of the title compound is described. The crystallographic studies showed that the p-bromophenyl group is very nearly coplanar with the 1,2,4-oxadiazole ring. The nearly planar phthalimide group makes an angle of about 98° with the bromophenyloxadiazole plane. Semi-empirical (AM1) and ab initio (STO-3G, 6-31G) molecular orbital calculations have been carried out for this compound and a comparison of bond angles, bond lengths and torsion angles has been made with the experimental values, which are remarkably close to each other. This compound crystallizes in the monoclinic space group P21/c with a = 13.6299(2),b = 13.9836(2), c = 8.4817(2) Å, = 101.9070(10)°, V = 1581.79(5) Å3, and Z = 4.  相似文献   

20.

Abstract  

The reaction of phosphorus ylide Ph3PCHC(O)C6H4–4–Br with HgCl2 in equimolar ratios using methanol as a solvent is reported. This reaction led to binuclear complex C-Coordination of ylide and trans-like structure of complex [Br–BPPY HgCl2]2·2CHCl3(1) is demonstrated by single crystal X-ray analyses and IR, 1H and 31P NMR spectroscopy. Elemental analyses indicate a 1:1 stoichiometry between the ylide and Hg(II) in the product two Hg atoms are four-coordinate in the form of a tetrahedral. The title molecule [Hg2Cl4(C26H29BrOP)2]·2CHCl3(1) has a crystallographic inversion centre at the centroid of the four-membered ring formed by the two Hg atoms and two Cl atoms, with one short Hg–Cl(2.393A°) bond, one Hg–C bond and two asymmetric bridging Hg–Cl (bonds at distances o 2.7345 and 2.2.7090A. The crystal packing is stabilized by C–H…O hydrogen bonds.  相似文献   

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