Phenyl Ring Orientations in Two Tetracyclone Adducts; X-Ray Crystal Structures of exo-and endo-1,7,8,9-Tetraphenyltricyclo-[5.2.1.02,6]deca-3,8-dien-10-ones

1985 ◽  
Vol 38 (8) ◽  
pp. 1223
Author(s):  
JM Coxon ◽  
MJ O'Connell ◽  
PJ Steel
Keyword(s):  
Crystal Structures ◽  
Phenyl Ring ◽  
X Ray ◽  
Phenyl Rings

The crystal structures of exo- and endo- 1,7,8,9- tetraphenyltricyclo [5.2.1.02,6]deca-3,8-dien-10-one (8) and (9) are reported. Crystals of the exo adduct (8) are triclinic: Pī , a 9.863(2), b 10.738(2), c 13.634(2) Ǻ, α 82.90(1), β 68.87(1), γ 66.87(1)°, Z 2; crystals of the endo adduct (9) are monoclinic: P21/c, a 11.610(1), b 7.862(2), c 27.675(3) Ǻ, β 100.223(9)°, Z 4. The structures were refined to R 0.039 and 0.049 respectively. The relative orientations of the four phenyl rings in the two structures are similar.

Structure and Molecular Motions in Rubidium Tetraphenylborate

2002 ◽  
Vol 57 (11) ◽  
pp. 847-853 ◽  
Author(s):  
A. Pajzderska ◽  
H. Małuszyńska ◽  
J. Wa̡sicki
Keyword(s):  
Potential Energy ◽  
Small Angle ◽  
Phenyl Ring ◽  
Unit Cell ◽  
Molecular Motions ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Ring Rotation ◽  
Phenyl Rings

By X-ray diffraction it was found that at 293 K the crystals of rubidium tetraphenylborate are tetragonal, space group I42m, a = b = 11.212(2) Å, c = 8.098(2) Å , with 2 molecules of Rb+[C24H20B]- in the unit cell. The molecular reorientations as functions of temperature were studied by 1H NMR. Two types of motions were detected: an anisotropic reorientation of the tetraphenylborate anions about their mass centres, and small-angle reorientations / oscillations of the phenyl rings. The dependence of the potential energy of the anion in the crystal on the angle of the phenyl ring rotation about the B-Ph bond was obtained on the basis of atom-atom calculations. The dynamics of this compound was compared to that of tetraphenyltin.

scholarly journals NMR and X-ray Studies Concerning Structure of 6,6’-(Oxybis(4,1-phenylene))bis-(2-allylpyridazin- 3(2H)-one)

2014 ◽  
Vol 22 (1) ◽  
pp. 25-38 ◽  
Author(s):  
Vasilichia Antoci ◽  
Mircea Apostu ◽  
Catalina Ciobanu ◽  
Dorina Mantu
Keyword(s):  
Phenyl Ring ◽  
Room Temperature ◽  
Heterocyclic System ◽  
Crystal Packing ◽  
Diphenyl Ether ◽  
The Novel ◽  
X Ray ◽  
Pyridazine Ring ◽  
Phenyl Rings ◽  
C Nmr

Abstract The structural NMR and X-ray studies of 6,6’-(Oxybis(4,1- phenylene))bis-(2-allylpyridazin-3(2H)-one), a bis-pyridazine derivative heterocycle, are reported in this study. Both 1H- and 13C- NMR confirm the proposed structure of compound. In order to establish unequivocally the structure of compound, the X-ray data analysis was performed. The compound crystallizes in the triclinic P-1(2) space group with a = 10.3699(7) Å, b = 10.6972(6) Å, c = 11.0449(4) Å, α = 87.941(5)°, β = 75.564(5)°, γ = 72.055(5)°, V= 1127.68 (12) Å3 and Z = 2. Molecular and crystal packing parameters for the novel heterocyclic system were obtained from intensity data collected at room temperature. The two phenyl rings (from the diphenyl ether moiety) are perpendicular one to each other and, on its turn, each phenyl ring is almost coplanar with the pyridazine ring

Structural Investigation of Two 4-AryIhexahydro-1H,3H-pyrido[1,2-c]pyrimidine-1,3-diones

2000 ◽  
Vol 55 (11) ◽  
pp. 1089-1094 ◽  
Author(s):  
Irena Wolska ◽  
Franciszek Herold
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Crystal Structures ◽  
Structure Determination ◽  
Phenyl Ring ◽  
Structural Investigation ◽  
X Ray ◽  
Saturated Ring ◽  
Centrosymmetric Dimers

The X-ray crystal structure determination of 4-(4'-fluorophenyl)hexahydro-1H,3H-pyrido[ 1,2-c]pyrimidine-1,3-dione (5) and 4-(4'-chlorophenyl)hexahydro-1H,3H-pyrido [1,2-c]- pyrimidine-1,3-dione (8) is reported. The crystal structures show the formation of centrosymmetric dimers via intermolecular N-H···O hydrogen bonds. The saturated ring adopts a slightly distorted sofa conformation both in 5 and in 8. In either compound the planar phenyl ring is twisted with respect to the pyrimidine-1,3-dione fragment.

Röntgenstrukturanalyse von N-[3,3-Dimethyl-5,5-bis- (trifluormethyl) -1 -pyrazolinio] pentafluoranilid / X-ray Structure Analysis of N-[3,3-Dimethyl-5.5-bis(trifluoromethyl)- ] -pyrazoliniojpentafluoroanilid

1982 ◽  
Vol 37 (12) ◽  
pp. 1606-1611
Author(s):  
Alfred Gieren ◽  
Viktor Lamm
Keyword(s):  
Structure Analysis ◽  
Title Compound ◽  
Phenyl Ring ◽  
Crystal Packing ◽  
Dominant Role ◽  
Direct Methods ◽  
Ring System ◽  
Monoclinic Space Group ◽  
X Ray ◽  
Phenyl Rings

The title compound crystallizes in the monoclinic space group P21/n with a - 8.761(3), b - 9.773(5), c = 18.727(7) Å, y = 100.86(3)°, V = 1574.7.Å3, Z = 4. The structure was solved by direct methods and the refinement converged for 2030 independent reflections to an JR-value of 0.060 (Rw = 0.071). The N-N distances in the mesoionic -N⊖-N⊕(R) = Nmoiety are asymmetric with 1.304 and 1.263 Å, respectively. The almost planar heterocyclic pyrazolinium ring system and the plane of the aromatic pentafluorophenyl group include an angle of 60° caused mainly by a torsion around the N-C bond to the phenyl ring. The crystal packing contains columnar stacks of parallel phenyl rings with distances of 3.30 and 3.35 Å. Also H-F contacts play a dominant role

Chemistry and crystal structures of 1,3-Bis(4'-bromophenyl)propane- 1,2,3-trione, 3,5-Diphenyl- 1,2-dithiolylium-4-olate and 4-Hydroxy-3,5-diphenyl-1,2-dithiolium perchlorate

1978 ◽  
Vol 31 (2) ◽  
pp. 297 ◽  
Author(s):  
JR Cannon ◽  
KT Potts ◽  
CL Raston ◽  
AF Sierakowski ◽  
AH White
Keyword(s):  
Crystal Structures ◽  
Heterocyclic System ◽  
Cycloaddition Reaction ◽  
Heterocyclic Ring ◽  
Dipolar Cycloaddition ◽  
Carbonyl Groups ◽  
X Ray Diffraction ◽  
Full Matrix ◽  
X Ray ◽  
Phenyl Rings

In connection with studies on possible mesoionic systems, syntheses of 1,3-bis(4'-bromophenyl)-propane-1,2,3-trione (5), 3,5-diphenyl-1,2-dithiolylium-4-olate (9) and 4-hydroxy-3,5-diphenyl-1,2-dithiolium perchlorate (10) have been reexamined. ��� The crystal structures of (5), (9) and (10) have been determined by X-ray diffraction from diffractometer data at 295 K and were refined by full-matrix least squares to residuals of 0.050 (1118 'observed' reflections), 0.072 (2388) and 0.087 (2000), respectively. Crystals of (5) are monoclinic, C2/c, a 18.535(4), b 7.734(2), c 12.184(3) Ǻ, β 126.60(3)°, Z 4. Crystals of (9) are orthorhombic, Pmcn, a 26.047(6), b 7.170(2), c 6.431(2) Ǻ, Z 4. Crystals of (10) are monoclinic, P21/a, a 18.601(7), b 10.636(4), c 8.152(2) Ǻ, β 102.60(3)°, Z 4. ��� In (5) π-character is localized in the phenyl rings and carbonyl groups [<C=O> 1.22(1) Ǻ] and the substance is best represented as a normal vicinal triketone. In (9) and (10) S-S bonds are present and (9) is correctly regarded as a heterocyclic system. The geometry of the heterocyclic ring in (10) agrees well with that previously found for the 1,2-dithiolium cation; <C-O> is 1.35(1) Ǻ. In (9) the heterocyclic C-C distances [1.442(2)Ǻ] are longer than in (10); this indicates diminished aromaticity on deprotonation. The C-C-C angle [111.2(2)°] in (9) is also smaller than that [118.3(8)°] in (10) and <C-O> in (9) is 1.250(3) Ǻ. ��� The behaviour of 1,3-diphenylpropane-1,2,3-trione (4) and (9) with acetylenic dipolarophiles has been studied but no evidence has been obtained that either substance undergoes a 1,3-dipolar cycloaddition reaction.

Synthesis and Crystal Structure Studies on 1N-Acetyl-3-Phenyl-5-(3,4,5-trimethoxyl-phenyl)-2-Pyrazoline

2014 ◽  
Vol 926-930 ◽  
pp. 262-265
Author(s):  
Huan Mei Guo ◽  
Yun Chen Zhang ◽  
Yu Feng Li
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Dihedral Angle ◽  
Phenyl Ring ◽  
X Ray Diffraction ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
Phenyl Rings

1N-Acetyl-3-phenyl-5-(3,4,5-trimethoxyl-phenyl)-2-pyrazoline has been synthesized and the crystal structure has been determined by means of single-crystal X-ray diffraction. The pyrazolinyl ring and the phenyl rings at 3 positions of the pyrazoline are almost coplane , with their dihedral angle to be 6.63(2) o. Phenyl ring at 5 positions and pyrazolinyl ring are almost perpendicular, the dihedral angle is 78.03(3) o.

Crystal chemistry of tetraradial species. Part 10. Tilting at windmills: conformations of the tetraphenyl species ZPh40, ±1 (Z = B, C, N)

2002 ◽  
Vol 80 (10) ◽  
pp. 1351-1366 ◽  
Author(s):  
Osvald Knop ◽  
Kathryn N Rankin ◽  
T Stanley Cameron ◽  
Russell J Boyd
Keyword(s):  
Ground State ◽  
Phenyl Ring ◽  
Free Molecule ◽  
X Ray ◽  
Benzene Rings ◽  
Phenyl Rings ◽  
Statistical Studies ◽  
The Difference ◽  
Induced Changes ◽  
Equilibrium Geometries

The equilibrium geometries of the isoelectronic ZPh40, ±1 (Z = B, C, N) molecules have been optimized, in S4 and D2d symmetries, at the HF/6-31G(d,p) and B3LYP/6-31G(d,p) levels, with the phenyl rings constrained to be planar. The ground-state conformations of all three species are shown to be of S4 symmetry, but the difference of the energies of the S4 and the D2d conformations is estimated to amount to only ~1 kcal mol–1, with a barrier to concerted rotational reorientation of the phenyl rings of ~5.0 kcal mol–1 for BPh–4, ~6.4 kcal mol–1 for CPh4, and ~7.9 kcal mol–1 for NPh+4. A redetermination of the crystal structure of CPh4 from –60°C X-ray data agrees with the results of previous determinations at ambient temperature; the CPh4 molecule in the crystal is slightly compressed along the S4 axis relative to the free molecule, otherwise the geometries of the two are essentially the same. Correlations between the optimized geometric parameters of the ZPh40, ±1 molecules have been examined and analyzed in detail, as have the substitution-induced changes in the geometry of the phenyl ring. The results confirm and strengthen the conclusions from the statistical studies by Domenicano et al. on the geometry of benzene rings monosubstituted by atoms of elements from the first row of the Periodic system.Key words: tetraphenylborate, tetraphenylmethane, tetraphenylammonium, ab initio molecular geometries.

New Peroxidizing Herbicides: Activity Compared with X-Ray Structure

1993 ◽  
Vol 48 (3-4) ◽  
pp. 334-338 ◽  
Author(s):  
Hitoshi Kohno ◽  
Kenji Hirai ◽  
Masahiro Hori ◽  
Yukiharu Sato ◽  
Peter Böger ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Growth Inhibition ◽  
Photosynthetic Pigments ◽  
Phenyl Ring ◽  
Molecular Size ◽  
X Ray ◽  
Phytotoxic Activity ◽  
Phenyl Rings

The crystal structure of 3-(4-chloro-5-cyclopentyloxy-2-fluorophenyl)-5-isopropylideneoxazolidine- 2,4-dione (BW -4), chlorophthalim and oxyfluorfen were determined by X -ray analysis. The molecular size of these compounds was almost the same, but the angle between the oxazolidine and the phenyl ring (BW -4), the imide and phenyl ring (chlorophthalim ) and between the two phenyl rings (oxyfluorfen) differed. The phytotoxic activities, determined by growth inhibition of Scenedesmus cells, loss of chlorophyll, and peroxidative destruction of photosynthetic pigments, were different among these compounds. The angle and length of BW-3, BW-4 and oxyfluorfen showing best phytotoxic activity were found approximately 65 -95 ° and 11 - 13 Å, respectively. These preliminary findings indicate that both angle and length of the molecule have some bearing on peroxidative activity.

scholarly journals Anion receptors containing thiazine-1,1-dioxide heterocycles as hydrogen bond donors

2010 ◽  
Vol 6 ◽  
Author(s):  
Hong-Bo Wang ◽  
James A Wisner ◽  
Michael C Jennings
Keyword(s):  
Hydrogen Bond ◽  
Crystal Structures ◽  
Anion Recognition ◽  
Anion Receptors ◽  
X Ray ◽  
Phenyl Rings ◽  
Hydrogen Bond Donors

The synthesis, X-ray crystal structures and anion recognition properties of two receptors containing thiazine-1,1-dioxide heterocycles as hydrogen bond donating subunits are reported. The newly synthesized receptors display much different anion selectivities in acetone-d 6 than N,N′-diphenyl-1,3-disulfonamidobenzene that was used as a comparison. The selectivity exhibited by one of the new receptors for chloride anions can be attributed to greater steric demand in the cleft formed, in part, by its terminal phenyl rings; an effect that is absent in the comparison receptor.

Transmission electron microscope studies in special ceramics

1978 ◽  
Vol 36 (1) ◽  
pp. 268-269
Author(s):  
A. Zangvil ◽  
L.J. Gauckler ◽  
G. Schneider ◽  
M. Rühle
Keyword(s):  
Phase Diagrams ◽  
Crystal Structures ◽  
Thin Foil ◽  
Limited Extent ◽  
Complex Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Electron Microscopes ◽  
Lattice Resolution

The use of high temperature special ceramics which are usually complex materials based on oxides, nitrides, carbides and borides of silicon and aluminum, is critically dependent on their thermomechanical and other physical properties. The investigations of the phase diagrams, crystal structures and microstructural features are essential for better understanding of the macro-properties. Phase diagrams and crystal structures have been studied mainly by X-ray diffraction (XRD). Transmission electron microscopy (TEM) has contributed to this field to a very limited extent; it has been used more extensively in the study of microstructure, phase transformations and lattice defects. Often only TEM can give solutions to numerous problems in the above fields, since the various phases exist in extremely fine grains and subgrain structures; single crystals of appreciable size are often not available. Examples with some of our experimental results from two multicomponent systems are presented here. The standard ion thinning technique was used for the preparation of thin foil samples, which were then investigated with JEOL 200A and Siemens ELMISKOP 102 (for the lattice resolution work) electron microscopes.

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