On the stereochemistry of 7-[1(2-carbomethoxyanilino)-1-(pyridyl)-methyl]-quinolin-8-ol (CMAP-oxine)

C₂₃H₁₉N₃O₃, P1 , a = 11,683(3), b = 7.740(2), c = 14.445(3) Å, α = 131.02(8), β = 95.43(8), γ = 95.02(8)°, D_x = 1.328 Mg · m⁻³, V = 0.9614 · 10⁻²⁷ m³, Final R = 0.059 for 2905 symmetrically independent reflections (|F₀| ≧ 3σ(F₀)). The intensities were measured with an automatic diffractometer. There are two molecules in the unit cell. The substance is not tridentat in potentially coordination behaviour; coordination takes place (twodentat) on the oxine group.     

Crystal and Molecular Structure of 1-Ethyl-3-[tris(trimethylsiloxanyl)silyl]pyrrolinium Hydrochloride

The crystal and molecular structure of 1-Ethyl-3[tris(trimethylsiloxyl)silyl]pyrrolinium hydro-chloride (C₁₅H₃₈N⁺O₃Si₄ · C¹⁻) has been determined by direct methods. The title compound crystallizes in the monoclinic space group C2/c with a = 20.640(3), b = 19.494(2), c = 27.34(3) Å, β = 90.60(4)°, V = 11000(13) ų, Z = 16, D_x = 1.034 Mg m⁻³. There are two molecules with different conformations in the crystal. The pyrroline rings are non-planar.-The Si O Si angles range from 149(1)° to 163(1)°. Two of the SiMe₃ groups are disordered. All molecules are connected by C¹⁻ – N⁺ contacts and C¹⁻ - HN⁺ hydrogen bonds to form double chains.     

Structures of azomethine imines of the pyrazolid-3-one-type (V). The structure of 1-[pyrenyl-(1)-methylene]-5,5-dimethyl-pyrazolid-3-one-betaine.

C₂₂H₁₈N₂O, P2₁, a = 7.473(2), b = 13.563(3), c = 18.264(3) Å, β = 115.49(4)°, Z = 4, U = 1670.9(6) ų, D_x = 1.295 Mg m⁻³, μ(MoKα) = 0.855 cm⁻¹, crystal size: 0.3 × 0.2 × 0.2 mm, colour: yellow. Final R = 0.086 for 1973 independent reflections excluding those with |F₀ < 3σ(F₀). The intensities were measured with an automatic diffractometer. There are two symmetrically independent molecules in the unit cell. The azomethine imine parts of the molecules are similar to those of four other relevant structures determined by X-ray analysis. A polymethinic part of a molecule is linked with an aromatic part via the bond C(4)–C(5). The mean pyrenyl plains and the mean plains of the five membered rings include dihedral angles of 29.6° for molecule A and 23.7° for molecule B.     

Syntheses,characterization and crystal structures of two structurally similar Schiff bases isonicotinic acid [1-(3-methoxy-2-hydroxyphenyl)methylidene]hydrazide and isonicotinic acid [1-(4-dimethylaminophenyl)methylidene]hydrazide monohydrate

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.     

Crystal and Molecular structure of 3,3-Diethyl–2,4,6–[1 H,3 H,5 H] Pyrimidine Trione

C₈H₁₂O₃N₂, M_r = 184.19, Trigonal, R3 (hexagonal axes) a = b = 26.800(1) Å, c = 6.828(3) Å, α = β = 90°, γ = 120°, V = 4247.11 ų, Z = 18, D_m = 1.297 Mg m⁻³, D_c = 1.296 Mg m⁻³, mu = 0.79 mm⁻¹, F(000) = 1764, T = 293 K, final R = 0.080 for 1205 observed reflections. There are two crystallographically independent molecules in the unit cell of the title compound.     

Structural,spectroscopic properties and theoretical studies of (E)-1-(4-Bromophenyl)-3-(2,3,4-trimethoxyphenyl)prop-2-en-1-one as a potential anti-oxidant agent

The new chalcone compound namely (E)-1-(4-Bromophenyl)-3-(2,3,4-trimethoxyphenyl)prop-2-en-1-one (C₁₈H₁₇BrO₄) is crystallized in the monoclinic crystal system of P2₁/c space group. The unit cell dimensions are: a = 8.0753 (10) Å, b = 21.873 (3) Å, c = 9.3362 (12) Å, α = 90°, β = 99.369 (2), γ = 90° and Z = 4. The single crystal was grown using slow evaporation solution growth technique. The newly synthesized compound was characterized by using IR, ¹H- and ¹³C-NMR, UV-Vis and single crystal X-ray diffraction analyses. Quantum chemical method of Density Functional Theory (DFT) with B3LYP/6-311++G(d,p) has been employed to study the structural and spectral properties of the compound. The electronic absorption spectrum was calculated using the time dependent functional theory (TDDFT) method. The most stable conformer of the title chalcone is identified from the computational results. Hirshfeld surface analysis with fingerprint plots has been used as a graphical tool for visualization and understanding of intermolecular interactions. Intermolecular C?H····O interaction observed stabilize the crystal structure, forming an infinite one dimensional column. The effect of this intermolecular interaction in the solid state can be seen in the difference between the experimental and the theoretically optimized geometrical parameters. The crystal is transparent in the entire visible region and absorptive in the UV region. Information about the size, shape, charge density distribution and site of chemical reactivity of the molecule has been obtained by mapping electron potential (MEP). The other molecular properties like charge transfer are explain using Mulliken population analysis. The antioxidant test indicated that the 2,3,4-trimethoxy substitution on the bromide chalcone to be one of the favorable modification to enhance its metal chelating activity.     

Crystal and Molecular Structure of Tosyl Pyrrolidine-2-Methanol (C12H17SO3N)

C₁₂H₁₇SO₃N, M_r = 255.33, Orthorhombic, P2₁2₁2₁, a = 11.703(1) Å, b = 14.797(3) Å, c = 14.971(2) Å, V = 2592.52 ų, Z = 8, D_m = 1.309 Mgm⁻³, D_c = 1.308 Mgm⁻³, mμ = 21.57 cm⁻¹, F(000) = 1088, T = 290 K, final R = 0.080 for 2416 unique reflections. There are two crystallographically independent molecules in the unit cell of the title compound.     

Crystal structure of marmesin,C14H14O4, 2-(β-hydroxyisopropyl)-2,3-dihydro-6,7-furano-coumarin

The unit cell parameters of this compound were determined by least-squares calculations from the adjusted angular setting of 25 general reflections. The crystals are monoclinic with the following crystallographic data: a = 5.718(1), b = 13.794(4), c = 7.861(1) Å, β = 100.53(2)°, Z = 2 and D_x = 1.34 g · cm⁻³. The space group according to the systematic absences is P2₁. The structure of this compound was solved by direct methods and refined by full matrix least-squares with anisotropic temperature factors to R = 0.04. The refined atomic positions indicate a considerable strain within the molecule. The structure is built up from molecules connected by H-atoms forming infinite chains along b-axis.     

Synthesis,Crystal Structure and Hydrogen-Bonding Patterns in (RS)-1-Carbamoyl Pyrrolidine-2-Carboxylic Acid

Abstract  

The title compound, N-carbamoyl-dl-proline, C₆H₁₀N₂O₃, crystallizes in the triclinic P-1 space group with unit cell parameters a = 7.610 (4) Å, b = 9.259 (5) Å, c = 11.749 (7) Å, α = 110.294 (11)°, β = 101.304 (13)°, γ = 91.391 (16)°, with two crystallographically independent molecules in the asymmetric unit. The ureido and carboxyl groups are equatorial and axial to the pyrrolidine rings, respectively. The pyrrolidine rings adopt envelope and twisted conformations in the residue A and B, respectively. The molecules are joined by N–H···O and O–H···O hydrogen bonds into cyclic structures with graph set R ₂²(8), forming infinite chains parallel to the cb plane with graph set C ₂²(14), that are further connected via N–H···O hydrogen bonds into a three-dimensional network.     

Structures of the Triclinic and the Monoclinic Modification of Divascan®

Trielinic modification: C₁₂N₄O₃H₁₆. Mr = 264.26, triclinic P 1 , a = 7.702(3), b = 9.420(11),c = 10.893(8) A, α = 73.37(8), β = 82.22(5), γ = 66.30(6)°, V = 638(1) A³, Z = 2, D_m = 1.360 Mg m⁻³, D_x = 1.362 Mg m⁻³, λ(MoK_α) = 0,71062 A, μ = 0.1084 mm⁻¹, F(000) = 280, T = 296 K, final R = 0.0742, wR = 0.0758 for 1842 reflections. Monoclinic modification: C₁₂N₄O₃H₁₆·, 3/2H₂O, M_r = 291.28, monoclinic P 2₁,/c, α = 14.075(5), b = 12.631(6), c = 16.234(5) A, β = 99.25(3)°, V = 2849(1) A³,Z = 8, D_m = 1.338 Mg m⁻³, D_m = 1.359 Mg m⁻³, λ(MoK_α) = 0.71062 A, μ = 0.1134 mm⁻¹, F(000) = 1240, T = 296 K, final R = 0.0557, wR = 0.0691 for 1266 reflections. Comparison of the two independent Divascan® molecules of the monoclinic modification with the one of the triclinic modification demonstrates good agreement of related bond distances and angles in the molecules. Disorder of the hydroxyl groups of one Divascan® molecule of the monoclinic modification is announced by high vibration parameters of the related oxygen atom and a very short C O distance, which is not adequate to a real C O bond length.     

Crystal structure of 4,5-dihydro-6-(2-thienyl)-3(2H) pyridazinone azine, (C16H16N16S2)

M_r = 484, monoclinic, P 2₁/c, a = 5.567(1), b = 7.857(2), c = 19.194(10) Å, β = 99.97(3)°, V = 826.9 ų, Z′ = 2, D_x = 1.43 g · cm⁻³, F(000) = 372, MoKα, λ = 0.71069 Å, μ = 0.328 mm⁻¹, final R = 0.055 for 889 observed reflections, T = 293 K. The compound was prepared from a direct unusual reaction of 6-(2-thienyl)-2,3,4,5-tetrahydropyridazine-3-one with hydrazine hydrate. The structure was solved by direct methods and refined by full-matrix least squares. The molecule in the solid state consists of a dimer with its two equivalent halves related by a center of symmetry at the middle of the N N bond. Each molecular fragment is nearly planar and the N N bond between the two halves is 1.296(5) Å indicating that it is a partial double bond.     

Structures of Azomethine Imines of the Pyrazolidone-(3)-type, (III) The Structure of 1-[Anthryl-(9)-methylene]-pyrazolidone-(3)-betaine

C₁₈H₁₄N₂O, Pbca, a = 19.541(4) Å, b = 14.800(2) Å, c = 9.572(3) Å, Z = 8, U = 2768.3 ų, D_x = 1.32 g cm⁻³, μ(MoKα) = 0.93 cm⁻⁻¹, crystal size 0.5 × 0.2 × 0.1 mm, colourless. Final R = 0.077 for 1177 independent reflections excluded those with |F₀| < 8 σ(F₀). The intensities were measured with an automatic diffractometer. The azomethine imine unit of the molecule has a geometry in approximate agreement with a polymethinic electron structure. The conjugation of the azomethine imine unit with the anthryl unit is only small. The anthryl ring and the five membered pyrazolidone ring include a dihedral angle of 65.4°. The main intermolecular forces are C–H … N hydrogen bridges.     

Crystal structures of 3-[1-Benzenesulfonyl-3-phenylsulfanyl-1H-indol-2-yl]-1-[4-(methyl (I)/methoxy (II) phenyl)]-2-phenyl-propane-1-one

The compounds 3-(1-Benzenesulfonyl-3-phenylsulfanyl-1H-indol-2-yl)-1-[4-methyl (I)/methoxy (II)phenyl)]-2-phenyl-propane-1-one crystallize in triclinic space group P . The details are: compound I a = 11.941(6) ?, b = 12.154(7) ?, c = 13.006(7) ?, α = 63.124(8)°, β = 84.464(9)°, γ = 64.810(8)°, V = 1519.7(14) ?³, Z = 2, D _cal = 1.284 Mg m⁻³, and R = 0.0382 (wR = 0.0978); compound II a = 11.897(6) ?, b = 12.268(6) ?, c = 13.001(7) ?, α = 61.919(8)°, β = 83.480(8)°, γ = 64.676(7)°, V = 1504.0(14) ?³, Z = 2, D _cal = 1.333 Mg m⁻³, and R = 0.0422 (wR = 0.1049). The indole ring system in both the molecules I and II are not strictly planar and the dihedral angles formed by the pyrrole and benzo planes are 4.0(7)° and 3.5(8)°, respectively. The C–HO, C–Hπ and ππ types of interactions stabilize the molecules in the unit cell in addition to van der Waal's forces in I and II.     

Crystal and molecular structures of N-alkyl-N,N-dimethyl-3-(heptamethyltrisiloxan-3-yl) propylammonium bromides

C₁₆H₄₂NO₂Si₃Br: M_r = 444.76, monoclinic space group P 2₁/c, a = 23.300(8), b = 8.918(4), c = 13.403(2) Å, β = 101.69(4)°, V = 2727(1) ų, D_x = 1.08 Mgm⁻³, D_exp = 1.06 Mgm⁻³, Z = 4, F(000) = 932, λ(MoKα) = 0.71069 Å, μ = 16.3 cm⁻¹. The crystal structure was determined by direct methods and refined by least-squares procedure to the discrepancy factor R = 0.117. C₁₅H₄₀NO₂ Si₃Br: M_r = 430.34, monoclinic space group P2₁/c, a = 23.460(4), b = 8.518(2), c = 13.403(2) Å, β = 102.03(2)°, V = 2619(1) ų, D_x = 1.09 Mgm⁻³, D_exp = 1.07 Mg⁻³, Z = 4, F (000) = 920, λ(MoKα) = 0.71069 Å, μ = 33.9 cm⁻¹. The crystal structure was determined by least-squares refinement of the structure model derived from structure determination of C₁₆H₄₂NO₂·Si₃Br to the discrepancy factor R = 0.099. C₁₆H₄₂NO₂Si₃Br: Daten siehe oben. C₁₅H₄₀NO₂Si₃Br: Daten siehe oben.     

Crystal Structure of [4-(Methylsulfanyl)Phenyl]Acetic Acid

Abstract  

The title compound, C₉H₁₀O₂S, (I), crystallizes in the triclinic space group, P − 1, with unit cell parameters a = 6.2249(3), b = 7.3733(5), c = 19.5708(12), Å, α = 86.746(5)°, β = 88.682(5)°, γ = 86.988(5)°, Z = 4. The molecule consists of a methyl sulfanyl group bonded to benzyl acetic acid at the 4 position crystallizing with two molecules in the asymmetric unit. The carboxylic acid group from the acetic acid moiety in these two molecules forms a classic O–H···O hydrogen bonded dimer with O···O distances of 2.673(2) and 2.646(2) Å, in a R₂² (8) graph-set motif which link the molecules into pairs around inversion centers in the unit cell. The dihedral angles between the mean planes of the R₂² (8) graph-set motif with the mean planes of the two nearby benzyl groups within the same dimer in the unit cell are 64.1(6)° and 71.3(4)°, respectively. Within the same dimer the dihedral angle between the two benzyl groups is 45.2(1)°. The structure is supported by a weak intermolecular C–H···Cg π-ring interaction and gives support to molecular packing stability in the unit cell. Comparison to a MOPAC AM1 computational calculation provides support to these observations.     

Static Disorder in Hexagonal Crystal Structures of C60 at 100 K and 20 K

C₆₀ · 2C₈H₁₀ (100 K): hexagonal space group P6₃, a = 23.694(4), c = 10.046(2) Å, V = 4884(2) ų, D_x = 1.903 g cm⁻³, Z = 6, F(000) = 2856, γ(CuKa) = 1.54178 Å, μ = 0.84 mm⁻¹. C₆₀ · 2C₈H₁₀ (20 K): hexagonal space group P6₃, a = 23.67(1), c = 10.02(1) Å, V = 4862(6) ų, D_x = 1.912 g cm⁻³, Z = 6, F(000) = 2856, γ(CuKa) = 1.54178 Å, μ = 0.84 mm⁻¹. The structures were determined by Patterson syntheses and rigid-body refinements. The C₆₀ molecules show two orientations with one molecular centre in common. The solvent molecules are disordered too. Static disorder could not be overcome or influenced by cooling down. A coordination number of 10 was found for the fullerene molecules.     

X-ray structure analysis of 1-(4-bromophenyl)-3-(4-chlorophenyl)-prop-2-en-1-one

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.     

Synthesis Characterization and Crystal Structure of 2-(3,4,5-trimethoxyphenyl)-1-(4-fluorophenyl)-4,5-diphenyl-1H-imidazole

The title compound, C₃₀H₂₅FN₂O₃, was prepared from the four-component one-pot condensation reaction and the product crystallized using dimethylformamide. The structure of the compound was established by elemental analysis, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), UV-Visible, and single-crystal X-ray diffraction. The compound crystallizes in the triclinic crystal system with the space group Pī, with unit cell parameters a = 10.286(2) Å, b = 11.795(2) Å, c = 21.331(4) Å, α = 100.270(3)°, β = 90.093(3)°, γ = 90.062(3)°, and Z = 4. The crystal and molecular structure of the title molecule is stabilized by intra-molecular interactions of types C–H···N and C–H···O.     

5-Pyridine 4-yl-3H-(1,3,4) Oxadiazole-2 Thione Hydrochloride Monohydrate, (I), and 4 [5-Ethylsulfanyl)-(1,3,4) Thiadiazole-2-yl]-Pyridinium Perchlorate, (II)

Abstract  

The title compounds C₇H₈ClN₃O₂S, (I), and C₉H₁₀ClN₃O₄S_2, (II), both crystallize in monoclinic space group P2₁ /c with unit cell parameters (I) a = 7.9402(7), b = 10.6312(9), c = 11.7626(10), ?, β = 99.271(5)°, Z = 4 and (II) a = 5.1439(2), b = 9.0636(4), c = 27.1814 (7), ?, β = 95.116(2)°, Z = 4. In (I) the molecule consists of a 5-pyridine-4-yl group bonded to the carbon atom at the 5 position of (1, 3, 4) oxadiazole-2 thione hydrochloride monohydrate. The angle between the mean planes of the oxadiazole and pyridine rings is 9.6(6)°. Crystal packing in (I) is stabilized by strong N–H···O hydrogen bonds in concert with a solvent water molecule and weak O–H···Cl, O–H···S, N–H···Cl intermolecular interactions. The crystal structure of compound (II) consists of 4 [5-ethylsulfanyl)-(1, 3, 4) thiadiazole-2-yl]-pyridinium perchlorate, (C₉H₁₀N₃S₂)⁺(ClO₄)⁻, cation–anion pairs, containing strong intermolecular N–H···O hydrogen bonds and weak C–H···O and N–H···O intermolecular interactions operating between the ionic species that form a cooperative hydrogen-bonded, infinite chain O–H···O–H···O–H network which generates a sheet motif structure in the unit cell. It is also supported by weak intermolecular Cg···Cg π–π and Cl–O···Cg π-ring interactions which gives additional support to molecular packing stability in the unit cell. Geometry optimized MOPAC AM1 computational calculations on each compound provides support to the structural features in their respective crystal structures.     

Crystal and molecular structure of 1-(p-nitrophenyl)-2-acetylamino-3-brom-propen-2-on-1, C11H9BrN2O4

M_r = 313.11, orthorhombic space group Pbca, a = 8.165(1), b = 9.491(2), c = 32.207(5) Å V = 2496(1) ų, D_X = 1.667 Mgm⁻³, Z = 8, F(000) = 1248, λ(MoKα) = 0.71069 Å, μ = 32.7 mm⁻¹. The crystal structure was determined by direct methods and refined by least-squares procedure to the discrepancy factor R = 0.065. Positions of hydrogen atoms were calculated. The structure determined by x-ray analysis confirms the chemical results.