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1.
Abstract A new substituted pyrrole, a precursor of meso-free-porphyrins, has been synthesised and characterised by single-crystal X-ray diffraction: monoclinic, P21/c with a = 14.607(9) ?, b = 5.136(2) ?, c = 25.832(17) ?, β = 108.14(5)°, Mr = 349.41, V = 1841.6(18) ?3, Z = 4. The molecules are assembled in centrosymmetric dimers via strong N–H...O hydrogen bonds. The dimers are gathered into chains via C–H...π intermolecular interactions. Graphical abstract The molecules in 4-benzyl-5-methoxymethyl-3-methyl-1H-pyrrole-2-carboxylic acid benzyl ester are joined in dimmers by strong hydrogen bonds. The dimmers are aggregated in chains running along the b axis through C-H...?€ intermoleculear interactions. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

2.
Abstract Crystal structure of diphenylacetic acid has been solved by X-ray diffraction. The crystals are monoclinic, space group P21/c, with a = 12.254(4) ?, b = 7.2260(8) ?, c = 17.521(4) ?, β = 133.38(1)°, Mr = 212.24, V = 1127.6(5) ?3, Z = 4 and R = 0.045. A strong hydrogen bond links the molecules in dimers. The dimers are connected by weaker C–H···π and π···π interactions. A calculation was performed for the isolated molecule and for the dimer within the Hartree-Fock (HF) level with a 6-311G(d) basis set. In both calculations, the minimum of the energy is achieved with the phenyl rings assuming a more symmetric arrangement around the central carboxylic plane than is experimentally observed. Graphical Abstract In diphenylacetic acid the molecules are coupled in dimers by a strong hydrogen bonds. Weaker intermolecular interactions involving the aromatic ring π systems join the dimers together. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

3.
Abstract The crystal and molecular structure of trans-1,2-bis(2-benzothiazolyl)ethene is reported. Crystal data for 1: monoclinic, space group C 2/c, a = 24.926(3) ?, b = 4.843(1) ?, c = 11.164(1) ?, β = 105.274(5) °, V = 1300.0(3) ?3, and D c = 1.50 g/cm3 for Z = 4 and R = 0.028. The molecule crystallizes in the form of a colorless plate and forms one-dimensional slipped π-stacks. Graphical Abstract The title compound crystallizes to form 1D slipped π-stacks in the solid state. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

4.
Abstract A new pyrazine compound, has been synthesised and characterised by single-crystal X-ray diffraction: monoclinic, P21/c with a = 11.0707(3) ?, b = 5.23700(10) ?, c = 16.6997(5) ?, β = 103.5385(16)°, Mr = 376.40, V = 941.30(4) ?3, Z = 2. Each molecule possesses C i symmetry with the two halves of the molecule related by an inversion centre. C–H···π and C=O···π interactions held the molecules together. Index Abstract C–H···π and C=O···π intermolecular interactions in dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate Joana A. Silva, Ana C. Santos, Ana T. Marques, Manuela Ramos Silva, Ana Matos Beja, Abílio J. F. N. Sobrala In dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate, each molecule possesses C i symmetry. The molecules are assembled in chains via carbonyl···π interactions. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.  相似文献   

5.
Abstract The title compound containing two metal centers each complexes to one enantiopure chiral norephedrine-derived pyridyl-(bis) oxazoline (pybox) ligand and linked by two hydroxide bridges, crystallizes to give rodlike form in the space group P21(# 4). Cell Parameters are a = 10.2344(18) ?, b = 13.952(3) ?, c = 23.371(4) ?, β = 94.586(4)°, V = 3326.6(10) ?3. The metal-hydroxide motif forms a square plane at the center of the structure with the scandium centers exhibiting a distorted pentagonal bipyramid coordination sphere consisting of the chelating ligand and two additional triflouromethyl sulfonyloxy species positioned anti to each other. Graphical abstract The complex contains two metal centers each complexes to one enantiopure chiral norephedrine-derived pyridyl-(bis) oxazoline (pybox) ligand and linked by two hydroxide bridges. Structural report for Sc[(R,R)-norephedrine-pybox](OTf)3 dimeric complex Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

6.
Abstract The chemical preparation and crystal structure for a 4,4′-azodi(phenylcyanamide) salt) in the solid state are reported. This compound crystallizes in the triclinic space group P with the following unit cell parameters: a = 9.759(3) ?, b = 11.237(4) ?, c = 11.919(4) ?, α = 95.54(3)°, β = 98.50(3)°, γ = 109.39(2)°, Z = 1 and V = 1204.4(7) ?3. The 4,4′-azodi(phenylcyanamide) dianion, azodicyd2−, is approximately planar, with the cyanamide groups (–N=C=N) in an anti conformation relative to each other and the azo group (–N=N–) adopting the more thermodynamically stable trans conformation. The crystal X-ray analysis shows that there are one azo molecule cation, two tetrabutylammonium cations and one water molecule in unit cell. Intermolecular O–H···N hydrogen bonds may be effective in the stabilization of the crystal structure of this compound and to form linear chain structure in the packing. Index Abstract Synthesis and crystal structure of Bis (Tetrabutylammonium)(4,4′-Azodi(phenylcyanamide)) salt . [(n-Bu)4N]2[Azodicyd2-] · H2O Davar M. Boghaei 1*, Fatemeh Behzadian-Asl 1 and Hamid Reza Khavasi2 1 Department of Chemistry, Sharif University of Technology, P.O. Box 11155-9616, Tehran, Iran 2 Department of Chemistry, Shahid Beheshti University, Evin, Tehran 1983963113, Iran Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

7.
Abstract A new compound 1-phenyl-3-methyl-4-(salicylidene hydrazide)-phenylethylene-pyrazolone-5 (PMPeP-SHZ) has been synthesized and characterized by elemental analysis, IR spectrum, MS and single crystal X-ray diffraction. The compound crystallizes in a monoclinic, space group P2(1)/c with cell parameters: a = 10.8275(19) ?, b = 24.689(4) ?, c = 9.7167(16) ? and β = 95.127(4)°, Z = 4, S = 1.097. In the crystal structure, the compound presents in the diketo form. The structure exhibits both intra- and intermolecular hydrogen bonding and the molecules are interlinked through hydrogen bonds forming an infinite 2D network. The fluorescent result shows blue emission at room temperature in solid state. Graphical Abstract Synthesis, Characterization and Crystal Structure of 1-Phenyl-3- methyl-4-(salicylidene hydrazide)-phenylethylene-pyrazolone-5 Li Zhang, Guan-Cheng Xu, Lang Liu, Guang-Fei Liu, and Dian-Zeng Jia* Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

8.
Abstract A new 3D coordination polymer, [Cd(pzdc)(bpy)]n (1) (pzdc = pyrazine-2,3-dicarboxylic acid, bpy = 2,2′-bipyridine), has been hydrothermally synthesized and characterized by the elemental analyses, IR spectrum and single crystal X-ray diffraction. X-ray diffraction analysis reveals that 1 (C16H10CdN4O4) crystallizes in monoclinic space group P21/c, features an interesting 3D zipper-like networks constructed by 2D layers via strong π–π packing interactions. Cell unit parameter for 1: a = 9.767(1), b = 14.022(2), c = 13.719(2) ?, β = 100.86(1)o, and Z = 4. Graphical Abstract A new 3D coordination polymer, [Cd(pzdc)(bpy)]n (pzdc = pyrazine-2,3-dicarboxylic acid, bpy = 2,2′-bipyridine), has been hydrothermally synthesized and characterized by the elemental analyses, IR spectrum and single crystal X-ray diffraction. X-ray diffraction analysis reveals that [Cd(pzdc)(bpy)]n features an interesting 3D zipper-like networks constructed by 2D layers via strong π–π packing interactions.   相似文献   

9.
Abstract By inclusion complexation with the chiral host compound (R)-(+)-4,4′,6,6′-tetrachloro-2,2′-bis(hydroxydiphenylmethyl)-1,1′-biphenyl, racemic 3-methyl-2-pyrrolidinone was resolved and its (S)-(−)-enantiomer was isolated as a 1:1 inclusion complex, which crystallises in the orthorhombic crystal system in the space group P212121 (a = 14.1163(2) ?, b = 14.7140(3) ?, c = 17.2025(3) ?). By the inclusion complexation, the keto–enol equilibrium of the guest was frozen and the keto-form was isolated in a pure form. By X-ray structural study of the complex, the guest molecule included was elucidated to be the keto-form and its absolute configuration was determined to be (S). Index Abstract By inclusion complexation with (R)-(+)-4,4′,6,6′-tetrachloro-2,2′-bis (hydroxydiphenylmethyl)-biphenyl, racemic 3-methyl-2-pyrrolidinone was resolved and its (S)-(−)-enantiomer isolated and in addition the keto–enol equilibrium of the guest was frozen and the keto-form isolated. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

10.
Abstract Two new ligands, having flexible coordination ability, 1,5-bis(quinoline-2-carbaldehyde) thiocarbohydrazone and 1,5-bis(quinoline-2-carbaldehyde) carbohydrazone were synthesized and characterized by elemental analysis, IR, and UV spectral studies. The compounds exist in the thione/ketone tautomeric forms, as evidenced by IR spectral data. The structure of bis(quinoline-2-aldehyde) thiocarbohydrazone has been solved by single crystal XRD study. The compound C21H16N6S crystallizes in triclinic form with two independent molecules in the asymmetric unit, space group , Z = 4, V = 1856.1(6) ?3 with unit cell parameters a = 11.331(2) ?, b = 11.714(2) ?, c = 15.116(3) ?, α = 100.369(4)°, β = 109.512(4)° and γ = 90.134(4)°. Both molecules exist in the thione forms and show a Z–Z configuration about both azomethine bonds, with quinoline nitrogens on opposite sides. The N–N, N–C and the C–S bond distances of the thiocarbohydrazide moiety suggest extensive electron delocalization of the whole thiocarbohydrazone moiety. Index Abstract Synthesis and spectral studies of bisthiocarbohydrazone and biscarbohydrazone of quinoline-2-carbaldehyde: Crystal structure of bis(quinoline-2-aldehyde) thiocarbohydrazone, E. Manoj, M. R. Prathapachandra Kurup, E. Suresh. Bis(quinoline-2-aldehyde) thiocarbohydrazone crystallizes in the tricliniccrystal system with two independent molecules in the asymmetric unit, and exists in the thione tautomeric form. Both molecules show a Z-Z configuration about both azomethinebonds, with quinoline nitrogens on opposite sides. The N–N, N–C and the C–S bond distances of the thiocarbohydrazide moiety suggest extensive electron delocalization of the whole thiocarbohydrazone moiety . Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

11.
Abstract The crystal structure of title compound has been determined. The compound crystallizes in the triclinic system with space group P-1, lattice parameters; a = 9.2938 (5) ?, b = 11.9992 (7) ?, c = 25.5918 (13) ?, α = 91.343 (2)°, β = 95.8360 (10)°, γ = 101.005 (2)°, V = 2784.3 (3) ?3, Z = 4, X-Ray analysis reveals that the molecular backbone consists of tricyclic system with the central seven-membered ring in twisted chair-like conformation. Graphical abstract The crystal structure of 1,5-bis(4-methoxyphenyl)-3a-(2-phenyl-2H-1,2,3-triazol-4-yl)-4,5-dihydro-3aH-benzo[b][1,2,4]oxadiazolo[4,5-d][1,4]thiazepine was first determined by single-crystal X-ray diffraction which reveals that the molecular backbone consists of a tricyclic system with the central seven-membered ring in twisted chair-like conformation .  相似文献   

12.
Index Abstract  In the dinuclear compound (HPhen)2[Sm2(Hsal)8(H2O)2] · 2H2O (Hsal = o-HOC6H4CO2 , Phen = 1,10-phenanthroline), intermolecular hydrogen bonds and π–π stacking interactions between parallel aromatic rings result in the formation of a two-dimensional supramolecular network.   相似文献   

13.
Abstract Crystal structures for the isomeric compounds benzyl-(2-chloro-6-methylpyrimidin-4-yl)amine (1), as its hemi-hydrate, and benzyl-(4-chloro-6-methylpyrimidin-2-yl)amine (2) have been determined. Conformational differences lead to multiple molecules, i.e. two and three, in their respective structures. Layers feature in each of the crystal structures and are stabilized by substantial hydrogen-bonding interactions. Compound (1) crystallizes as a hemi-hydrate in the triclinic space group P-1 with a = 8.667(5) ?, b = 11.421(7) ?, c = 12.954(8) ?, α = 78.330(10)°, β = 84.553(10)°, γ = 75.510(9)°, and Z = 4. Compound (2) crystallizes in the monoclinic space group P21/c with a = 10.740(3) ?, b = 21.487(6) ?, c = 14.914(4) ?, β = 95.014(5)°, and Z = 12. Index Abstract Substantial hydrogen-bonding interactions leading to layer structures feature in each of the crystal structures of the isomeric title compounds. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.  相似文献   

14.
Abstract  Crystallization of tetraethylammonium chlorochromate (C2H5)4N[CrO3Cl], TEACC, with desirable particle size as a performance characteristic was used to illustrate the design procedure. Taguchi design of experiments (DOE) method has been used for to plan a minimum number of experiments and optimization of crystallization processes. Four factors, which influence the crystal size, crystal growth and nucleation, were chosen. These factors are concentration, temperature, type of solvent and method of crystallization. After optimization the results show that concentration is most effective factor that has largest percent of contribution 53.26% and type of solvent is least effective factor that has smallest percent of contribution 4.33%. The optimum conditions are vapor diffusion as method, 0.043 g/15 mL for concentration, 0 °C for temperature and acetonitrile as solvent. These conditions must be produced suitable crystals for single crystal X-ray diffraction experiment. These results confirmed by experimental data and the crystals of the optimum conditions found to have suitable properties for single crystal X-ray diffraction. These crystals had sent for single crystal X-ray diffraction and diffraction data gathered successfully. A red block crystal was mounted on a glass fiber. The X-ray data determined monoclinic system, space group C2(#5), with a = 12.023(3), b = 7.998(2), c = 14.527(4) ?, β = 114.187(4)°, V = 1274.4(6) ?3 and Z = 4. Index Abstract  The Taguchi design of experiments (DOE) method has been used for to plan a minimum number of experiments and optimization of crystallization processes. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

15.
Abstract 7,4′-bis-(hydroxyl)-8,3′,5′-tris-(hydroxymethyl)isoflavone (I) and its ester were synthesized and examined by IR, element analysis and 1H NMR. The crystal of 7,4′-bis-(acetyl oxide)-8,3′,5′-tris-(acetoxymethyl)isoflavone (II) was studied by X-ray diffraction. (II) crystallizes in the monoclinic with space group P2 1 /c. a = 17.987(3) ?, b = 17.972(3) ?, c = 8.4087(11) ?, β = 97.703(3)°, V = 2693.7(6) ?3 and Z = 4. The molecular structure of the ester consists of a benzopyranone moiety, a phenyl moiety, two acetyl oxides and three acetoxymethyl groups. Hydrogen bonds and aromatic stacking interactions link the ester into a two-dimensional structure. Index Abstract 7,4′-bis-(hydroxyl)-8,3′,5′-tris-(hydroxymethyl)isoflavone and its ester were synthesized and examined by IR, element analysis and 1H NMR. The result of the ester’s crystal structure showed that hydrogen bonding and aromatic π–π stacking assemble the ester into a two-dimensional networking structure.   相似文献   

16.
Abstract Three new isostructural coordination complexes, M(pca)3, where M = Co (1), Cr (2), or Rh (3) and 2-pyrazine-carboxylate (pca), have been synthesized solvothermally and characterized by single crystal X-ray diffraction and powder X-ray diffraction. In structures 1-3, the pca ligand chelates to the metal centers in a tris-chelating arrangement through proximal nitrogen and oxygen donor atoms. Structures 1-3 are monoclinic and crystallize in the space group C2/C. In structure 1, a = 28.066(13) ?, b = 8.036(4) ?, c = 13.577(6) ?, and β = 90.2(10)°. In structure 2 a = 28.318(3) ?, b = 8.089(4) ?, c = 13.792(12) ?, and β = 90.256(2)°. In structure 3, a = 28.679(4) ?, b = 8.051(13) ?, c=13.847(2) ?, and β = 90.585(2)°. Graphical Abstract Three new isostructural coordination complexes, M(pca)3, where M = Co, Cr, or Rh and 2-pyrazine-carboxylate (pca), have been synthesized solvothermally and characterized by single crystal X-ray diffraction and powder X-ray diffraction.   相似文献   

17.
Abstract The relation between the molar volume of metal oxides and their composition has been discussed. In order to compare molar volume of oxides with different compositions, the volume per one mole of oxygen atoms (Ma/bO) was used. It has been found that molar volumes of oxide phases of the same metal in the composition range 2 > a/b > 0.5 are linear functions of composition. This type of relationship has been proposed as an additional criterion to classify an oxide as a compact structure. Furthermore, in the case of oxides with metal ions in higher oxidation states (Mz+ > M4+) the increase of the molar volume (relative to the MO2 oxides) and the formation of framework structures have been found. Graphical Abstract Molar Volume and Composition of Oxides of the Same Metal Andrzej Stokłosa*, Barbara Laskowska Molar volumes of oxide phases of the same metal in the composition range 1>a/b>0.3 are linear functions of composition. The dependence of the effective molar volume (Veff) of the oxides Ma/bO on the composition (a/b) for the transition metal oxides and Ce oxides  相似文献   

18.
Abstract Two apigenin alkylation derivatives, 4′,7-dimethoxyl-5-hydroxyflavone (I) and 4′,7-diethoxyl-5-hydroxyflavone (II), have been synthesized and their crystal structures were determined by 1H NMR and single crystal X-ray diffraction study. (I) is triclinic, space group P−1 with a = 7.120(5) ?, b = 7.297(5) ?, c = 13.559(10) ?, α = 89.313(12)°, β = 86.298(12)°, γ = 83.999(13)° and Z = 2. (II) is monoclinic, space group P 21 /c with a = 16. 309(4) ?, b = 7.303(2) ?, c = 15.185(4) ?, α = 90.00°, β = 115.70(2)°, γ = 90.00° and Z = 4. They have the same flavone skeleton which is composed of a benzopyranone moiety and a phenyl moiety. Molecules of (I) are linked into a two-dimensional network by a combination of C–H···O hydrogen bond and π–π stacking interactions. (II) shows some discrepancies with (I) and the molecules are linked into a column by π–π stacking interaction. Graphical Abstract Two apigenin alkylation derivatives, 4′,7-dimethoxyl-5-hydroxyflavone (I) and 4′,7-diethoxyl-5-hydroxyflavone (II) were synthesized and their crystal structures were determined by single-crystal X-ray diffraction. Hydrogen bonding and π–π stacking interactions assemble (I) into a two-dimensional network, and in the crystal structure of (II), π–π stacking interaction leads to the formation of a column.   相似文献   

19.
Abstract  [Na(H2O)2(C18H15O6SO3)]2 was synthesized by sulfated 5-hydroxy-6,7,4′-trimethoxyisoflavone with concentrated sulfuric acid. Single-crystal X-ray diffraction study indicates that it is a dimeric centrosymmetric species. The coordination polyhedron of each Na(I) atom exhibits a distorted trigonal bipyramidal geometry. The dimeric units are linked by intermolecular hydrogen bonds C–H⋯π, C–H⋯O and O–H⋯O to result in a three-dimensional framework. Graphical Abstract  [Na(H2O)2(C18H15O6SO3)]2 was synthesized by sulfated 5-hydroxy-6,7,4′-trimethoxyisoflavone with concentrated sulfuric acid. The coordination polyhedron of each Na(I) atom exhibits a distorted trigonal bipyramidal geometry. The dimeric centrosymmetric units are linked by intermolecular hydrogen bonds C–H⋯π, C–H⋯O and O–H⋯O to result in a three-dimensional framework. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

20.
Abstract (4-Methylpiperidine-dithiocarbamato-S,S′)triphenyltin(IV) derivative of 4-methyl-1-piperidine carbodithioic acid (4-MePCDTA) have been synthesized and characterized by elemental, IR, multinuclear NMR (1H and 13C) and mass spectrometric studies. The crystal structure of the complex has been determined by X-ray single crystal analysis, which shows unsymmetrical nature of the ligand towards coordination to tin. It crystallizes in monoclinic P21/c space group with the crystal cell parameters: a = 10.1863(10) ?, b = 21.200(2) ?, c = 11.7332(11) ?, β = 111.2020(10)°, Z = 4 and V = 2,362.2(4) ?3. The tin atom is coordinated to the two sulfur atoms of the dithiocarbamate ligand and three carbon atoms of the phenyl groups are in distorted trigonal bipyramid geometry. This complex was tested for its antimicrobial activity against six different plant and human pathogens. The screening results show that the complex exhibit higher antibacterial and antifungal activity than the free ligand. Index abstract Synthesis, Spectroscopy, in vitro Biological Activity and X-Ray Structure of (4-Methylpiperidine-dithiocarbamato-S,S′)triphenyltin(IV) Saira Shahzadi, Saqib Ali and Mohammmed Fettouhi 4-Methyl-1-piperidine carbodithioic acid behaves as anisobidentate ligand and chelates the tin atom by means of sulfur atoms giving cis-trigonal bipyramid geometry around the tin atom. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

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