Crystal Structure of Potentially Mesomorphic 4-Nonyloxyphenyl-4'-Metacryloyloxy-Benzoate CH2=C(CH3)–COO–C6H4–COO–C6H4–O–С9Н19

Crystallography Reports - The crystal structure of 4,4'-substituted phenyl benzoate CH2=C(CH3)–COO–C6H4–COO–C6H4–O–С9Н19 has been investigated by...     

Crystal Packing of Potentially Mesomorphic Azobenezene Derivatives R1–C6H4–N=N–C6H4–R2 (R1, R2 = CH3COO,C2H5O; CH2=C(CH3)COO,C2H5; C6H13COO,C2H5O)

Crystallography Reports - The structure and thermal properties of azobenzene derivatives R1–C6H4–N=N–C6H4–R2, where R1/R2 = CH3COO/C2H5O (I), CH2=C(CH3)COO/C2H5 (II), or...     

C–H...O,C–H...π and π–π stacking interactions in 3-(2,4-dimethylphenyloxymethyl)-3,4-dihydroisocoumarin

3-(2,4-Dimethylphenyloxymethyl)-3,4-dihydroisocoumarin (C₁₈H₁₈O₃) was prepared by the alkylation of o-lithio N-methyl benzamide with 2-(2,4-dimethylphenoxy)methyl oxirane, followed by alkaline hydrolysis. The compound crystallizes in the orthorhombic space group Pbca with unit cell parameters : a = 8.239(2) Å, b = 14.918(5) Å, c = 24.831(9) Å, Z = 8. The crystal structure was solved by direct methods and refined to R = 0.0514 for 1564 observed reflections. The heterocyclic ring adopts a distorted half-chair conformation. Molecules are connected by π–π interactions between phenyl rings of the isocoumarin nucleus forming dimers. Dimers are connected via C–H...O hydrogen bonds forming chains. Further intermolecular C–H...π hydrogen bonds link the dimer chains to form supramolecular structure.     

The structure and conformation of the tryptophanyl diketopiperazines cyclo(Trp–Trp)·C2H6SO and cyclo(Trp–Pro)

The structure and conformation of the cyclic dipeptides [cyclo(L-Trp–L-Trp)·C₂H₆SO] and cyclo(L-Trp–L-Pro) have been investigated with X-ray crystallographic and spectroscopic methods. Cyclo(L-tryptophanyl-L-tryptophanyl)·DMSO solvate crystallized in the space group P2 ₁2₁2₁ with cell dimensions a = 6.193(2), b = 11.545(3), c = 31.117(4) Å. The crystal structure is stabilized by four hydrogen bonds (three intermolecular hydrogen bonds and one intramolecular bond). The first intermolecular bond is between the oxygen of DMSO and the nitrogen of indole ring 2, in contrast to the second intramolecular hydrogen bond between the nitrogen of indole ring 1 and the oxygen of DMSO. The two remaining intermolecular hydrogen bonds are between the nitrogens of the DKP ring and the carbonyl oxygens of the DKP ring. The values of ^1A ₁ (–45.764) and ^1A ₂ (67.437) indicate an extended side chain conformation for Trp residue 1 (E_N) and a folded conformation for Trp residue 2. The DKP ring is more planar than in other cyclic dipeptide compounds (₁ = 11.414, ₁ = –7.516, ₂ = 12.471, and ₂ = –8.256). In cyclo(L-Trp–L-Trp) the C resonance of L-tryptophan (29.88 ppm) is shifted upfield 0.82 ppm when compared with the same resonance in cyclo(L-Trp–L-Gly) (30.7 ppm) and cyclo(L-Leu–L-Trp) (30.7 ppm). Two conformations of cyclo(Trp–Pro) crystallized in the space group P1 with cell dimensions a = 5.422(1), b = 9.902(1), c = 13.443(2) Å, = 80.42(1), = 78.61(1), and = 89.13(1)°. The conformation of the backbone and the orientation of the aromatic side chains for these conformers are very similar. The DKP rings for both conformers adopt a typical boat conformation in contrast to the flattened chair conformation observed for cyclo(Tyr–Pro) and cyclo(Phe–F-Pro). The tryptophan side chains of these conformers are folded towards the diketopiperazine (DKP) ring. The pyrrolidine ring for conformer 1 can be described as an envelope (Cs–C-endo) conformation in contrast to the pyrrolidine ring symmetry for conformer 2 which is an intermediate between C_s and C₂ rather than pure C_s for the proline ring with C-endo and C-exo with respect to C. The two prolyl rings are puckered at the -carbon atoms which deviate from the best planes defined by the four remaining atoms. The crystal structures are stabilized by four intermolecular hydrogens bonds. An intermolecular bond between the nitrogen of the indole ring (conformer 1) and the carbonyl oxygen of the DKP ring (conformer 2) was observed. The second hydrogen bond is between the nitrogen of the indole ring (conformer 2) and the carbonyl oxygen of the DKP ring (conformer 1). The last two hydrogens involve the carbonyl oxygens of the DKP rings and the nitrogens of the DKP rings [carbonyl oxygen of DKP ring (conformer 1)––––nitrogen of DKP ring (conformer 2); nitrogen of DKP ring (conformer 1)––––––carbonyl oxygen of DKP ring (conformer 2)].     

Carbon–hydrogen and carbon–phosphorus bond cleavage in a triruthenium cluster complex containing dppm: The crystal and molecular structures of Ru3(CO)6{μ 3-OPPh2 C2H(C6H4)PPhCH2PPh}(μ 3-OPPh2)Ph and Ru3(CO)6 {μ-OPPh2C2H(C6H4)PPhO}(μ-PPh2)(μ-PPh2O)

The crystal and molecular structures of Ru₃(CO)₆{μ ₃-OPPh₂C₂H(C₆H₄)PPhCH₂PPh}-(μ ₃-OPPh₂)Ph (1) and Ru₃(CO)₆{μ-OPPh₂C₂H(C₆H₄)PPhO}(μ-PPh₂)(μ-PPh₂O) (2) have been determined by single crystal X-ray diffraction. Both complexes contain oxygen atoms oxidatively inserted into phosphorus–ruthenium bonds, and unique σ/π multidentate ligands formed from C $---{\text{H}}$ H and C $--$ P bond cleavage in bis(diphenylphosphino)acetylene and bis(diphenylphosphino)methane. Complex 1 crystallized in the triclinic space group ${\bar 1}$ , with lattice parameters a = 11.642(4) Å, b = 15.018(5) Å, c =16.587(5) Å, α = 2.48(3)°, β = 76.47(2)°, γ = 70.35(3)°, V = 2651.1(15) ų, Z = 2. Complex 2 crystallized in the centered monoclinic space group, C2/c, with lattice parameters a = 34.467(4) Å, b = 14.274(2) Å, c = 23.258(3) Å, β = 5.29(1)°, V = 11394(3) ų, Z = 8.     

配合物[Cu2(C6H2Cl2OC=N-C3H6COO)2(H2O)2]·3H2O合成与晶体结构

本文以苏氨酸,3,5-二溴水杨醛以及醋酸铜为原料合成了新型配合物[Cu2(C6H2Cl2OC=N-C3H6COO)2(H2O)2]·3H2O,并对其晶体结构经元素分析,红外光谱及X射线单晶衍射表征.结果表明:该晶体属单斜晶体结构,晶胞参数分别为:a=0.6985(2) nm, b=1.0789(2) nm, c=1.9639(3) nm, β=92.182(3) °, Mr=797.34, V=1.4789(6) nm3 , Z=2, Dc=1.790 g/cm3, μ(MoKa) =1.867 mm-1, F(000)=808, R=0.0321, wR= 0.0566.Cu(II)与一个N原子,两个O原子以及一个水分子构成三齿链状席夫碱.不对称单元结构包含两个配合物分子及三个由氢键链接的水分子.     

Metal-hydroxycarboxylate interactions: syntheses and structures of K2[VO2(C6H6O7)]2·4H2O and (NH4)2[VO2(C6H6O7)]2·2H2O

Potassium and ammonium dimeric (citrato)dioxovanadium(V) hydrate K₂[VO₂(H₂cit)]₂·4H₂O1 and (NH₄)₂[VO₂(H₂cit)]₂·2H₂O2 (H₄cit=citric acid) have been prepared and characterized by X-ray structure analyses. Vanadate1 crystallizes in the monoclinic space groupP2₁/n (No. 14) with unit cell parameters:a=9.304(2),b=11.756(2),c=11.911(2)Å, =111.72(3)°, andD _c=1.911 g/cm³,Z=2; Vanadate2 also crystallizes in the monoclinic space groupP2₁/n with unit cell parameters:a=9.719(2),b=11.111(3),c=11.294(2)Å, =109.03(2)°, andD _c=1.781 g/cm³,Z=2. Each dimer contains a centro-symmetric planar four-member V₂O₂ ring with two exocyclic citrate entities coordinated by the oxygen atoms of the hydroxy-and -carboxylate ligands, while the other two -carboxylate groups remain uncomplexed. Principal dimensions of the V–O bonds are 1.986(4)_av (hydroxy) and 1.980(3)Å(-carboxyl) for vanadate1, 1.988(2)_av (hydroxy) and 1.974(3)Å(-carboxyl) for vanadate2.     

Structure of progesterone hydroquinone monohydrate (1∶1∶1), C21H30O2·C6H6O2·H2O

The crystal structure of progesterone hydroquinone monohydrate was determined by means of X-ray diffraction methods:M _r=442.6, orthorhombic,P2₁2₁2₁,a=14.680(2),b=22.725(3),c=7.334(1) Å,V _a=2446.6(6) ų,Z=4,D _x=1.190 M gm^–3, MoK radiation ,(MoK)=0.75 cm^–1,F(000)=948. The structure was solved usingMultan;R=0.059,R _w=0.059 for 2736 reflections. This progesterone molecule has the most flattenedA ring, relative to the rest of the skeleton, of all progesterone molecules studied so far. Steroid, hydroquinone, and water molecules form, by means of hydrogen bonds, two parallel chains connected with each other by hydrogen bonds.The authors thank Dr. A. Szyczewski for supplying crystals. This research was supported by the project RP.II.10 from the Polish Ministry of National Education and by PHS Grant No. DK26546.     

[Co(H2O)6](C18H15O4SO3)2·4H2O的合成和晶体结构

以芒柄花素为先导化合物,合成了水溶性的[Co(H2O)6](C18H15O4SO3)2·4H2O,并采用IR, 1H NMR, TG-DTA, XRD和单晶X射线衍射法对其结构进行了表征.单晶X射线衍射结果表明:[Co(H2O)6]2+、C18H15O4SO 3和H2O之间存在多种氢键,形成晶体结构中的亲水区.异黄酮骨架间反平行排列,面对面和边对面芳香堆积作用同时存在于其中,构成晶体结构中的疏水区.磺酸根是连接亲水区和疏水区的桥梁.氢键、芳香堆积作用以及阴阳离子之间的静电引力共同将标题化合物组装成具有三维网络结构的超分子.     

Purported “melamine cyanuric acid trihydrochloride” C3H6N6⋅C3H3N3O3⋅3HCl is actually “diprotonated-melamine cyanuric acid dichloride dihydrate” (C3H8N6)2+⋅C3H3N3O3⋅2Cl−⋅2H2O

On the basis of the published results, melamine cyanuric acid trihydrochloride (MCA3HCl) is shown to be better described as diprotonated melamine cyanuric acid dichloride dihydrate (C₃H₈N₆)²⁺C₃H₃N₃O₃2Cl^–2H₂O. Details are given of the revised hydrogen bonding scheme, which requires further elaboration.     

Synthesis and crystal structure of [Ni(H2O)6](C19H17O9S)2·2H2O

A water soluble flavonoid sulfate, [Ni(H₂O)₆](C₁₉H₁₇O₉S)₂·2H₂O was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. The crystal of it belongs to triclinic crystal system, space group P–1. The results show that the title compound consists of [Ni(H₂O)₆]²⁺, C₁₉H₁₇O₆SO₃ ⁻ and H₂O. Ni(II) is located on the symmetry center and octahedrally coordinated by six water molecules. A variety of hydrogen bonds among [Ni(H₂O)₆]²⁺, C₁₉H₁₇O₆SO₃ ⁻ and the lattice water molecules build a hydrophilic region. Aromatic π–π stacking interactions assemble isoflavone skeletons into a column and the columns form a hydrophobic region of the title compound. The sulfo-groups bridge the hydrophilic regions and the hydrophobic regions as well as the inorganic components and organic components. Hydrogen bonds, stacking interactions and the electrostatic interactions between cation [Ni(H₂O)₆]²⁺ and anion sulfonate C₁₉H₁₇O₆SO₃ ⁻ lead the moieties to a three-dimensional structure.     

Database Survey of Single-and-Half Phosphorus–Oxygen Bonds in Salts with the C2PO2 Segment: Crystal Structure of [NH2C5H4NH][(C6H5)2P(O)(O)]⋅2H2O

Crystallography Reports - For structures with a C2PO2 skeleton, a comparison of “single-and-half” phosphorus–oxygen bonds with single and double phosphorus–oxygen bonds is...     

Synthesis,crystal structure and spectral studies of the complex [Ni(C3H4N2)4(H2O)2]·(C6H4COSO2N)2

The title compound has been synthesized and its crystal structure determined at room temperature.M _r =731.39, triclinic, space groupP¯1,a=9.020(3),b=11.280(7),c=7.784(2)Å,=97.05(4),=97.08(2), =105.32(4)°, U=748(1)ų,Z=1,D _calc.=1.624 g/cm³. The finalR is 0.030 for 3095 independent observed reflections withI3(I). The crystal structure consists of repeated [Ni(im)₄(H₂O)₂]²⁺ cations and noncoordinated saccharin anions. In the complex cation [Ni(im)₄(H₂O)₂]²⁺, Ni² is bonded to four N atoms from four imidazole molecules and two O atoms from two water molecules forming an approximately square octahedral stereochemistry. The d-d transition spectrum of the title compound is also reported and is explained perfectly with the scaling radial theory which was proposed by us.     

Structure of 6β-acetoxyprogesterone,C23H32O4

The X-ray crystal structure of 6-acetoxyprogesterone, C₂₃H₃₂O₄, has been determined. This compound crystallizes in space groupP2₁2₁2₁ witha=13.195(3),b=15.035(4),c=10.705(3) Å,V=2139.8(9) ų,M _r=372.5,Z=4,D _x=1.156g cm^–3; MoK radiation (=0.7107 Å),=0.72 cm^–1,F(000)=808;R=0.069, andR _w=0.052 for 1292 reflections. RingA adopts a normal 1,2-half-chair conformation. The side chain is typical for a 20-ketosteroid conformation.     

Phase Transition and Phase Diagram of Anion Radical Salts of [(C6H5)3PCH3]+ [(C6H5)3AsCH3]+ ×(TCNO)− 2 (0 ≤×≤ 1)

Abstract

Much attention has been paid to the solid anion radical salts of 7,7,8,8-tetracyanoquinodimethane (TCNQ), because of their prominent electronic properties.^1–4 In particular, the salts containing mixed cations represented by [(C₆H₅)₃PCH₃]⁺ _1–x [(C₆H₅)₃AsCH₃]⁺ _× (TCNQ)^? ₂, (0 ≤×≤ 1), are known to undergo phase transitions at 1 atm pressure in the solid state.^1–4 The phase transition of pure methyltriphenylphosphonium salt, (x = 0.00), takes place at 315.7 K. Heat-capacity measurements of this phase transition have been made by Kosaki et al. ³ The transition has thus been found to be of the first order. The enthalpy and the total entropy change associated with the phase transition were experimentally determined to be 485.18 cal/mol and 1.7206 cal/deg.mol, respectively. For the solid solutions, it was found that the transition temperature (T_c ) is increased, while the magnitude of the heat of transition (δH) is decreased, progressively with an increase in the composition parameter (x) and that pure methyltriphenylarsonium salt, (x = 1.00), has no such phase transition up to the decomposition temperature of about 480 K at 1 atm pressure.^1–3 Figure 1 shows the experimental relation between T _c and x, together with the relation between δH and x.⁴ In the present paper, we attempted to explain thermodynamically the phase diagram of Figure 1 for the solid solutions of those TCNQ anion radical salts.     

X-ray diffraction study of p-(alkoxybenzylidene)-p′-toluidines: Crystal and molecular structure of C10H21O-C6H4-CH=N-C6H4-CH3

The crystal and molecular structure of p-(decaoxybenzylidene)-p′-toluidine C₁₀H₂₁O-C₆H₄-CH=N-C₆H₄-CH₃ is studied. The molecule is nearly planar. In the crystal packing, loose regions formed by aliphatic fragments of molecules alternate with pseudostacks of aromatic fragments of molecules that are related by the centers of symmetry. The stacks are built of dimers, in which molecules are linked by π-stacking interactions between benzene rings. There are no weak directional interactions between dimers in a stack. The presence of a single structure-forming element in the crystal, namely, the π-stacking interactions in the dimers, along with the similarity of the crystal packing to that of the C₈H₁₇O-homologue, which forms a nematic mesophase on melting, indicate that the crystals under study should exhibit nematic properties.