Chemistry and crystal structures of tetrabenzoylethylene, its photolysis product and tetraacetylethylene

1978 ◽  
Vol 31 (6) ◽  
pp. 1265 ◽  
Author(s):  
JR Cannon ◽  
VA Patrick ◽  
CL Raston ◽  
AH White
Keyword(s):  
Solid State ◽  
Crystal Structures ◽  
Molecular Conformation ◽  
Crystallographic Analysis ◽  
Stable Form ◽  
Photolysis Product ◽  
Molecular Conformations ◽  
X Ray ◽  
The Difference ◽  
The Stability

X-ray crystallographic analysis has revealed that the light-sensitive form (A) and the light-stable form (A') of tetrabenzoylethylene are not valence tautomers but are two crystalline modifications of the same substance. The difference in the stability of these forms to light appears to be a consequence of their different molecular conformations and packing in the solid state. The molecular conformation of the A form is represented by (8) and that of the A' form by (9). The related tetraacetylethylene has the conformation (10) in the solid state. X-ray crystallographic analysis has also revealed that the photolysis product (B) of tetrabenzoylethylene is 4-phenoxy-3,4,6-triphenyl-1H,4H-furo[3,4-c]-furan-1-one (11). ��� The crystal structures of (8), (9), (10) and (11) were determined by X-ray diffraction: diffractometer data at 295 K were refined by least-squares techniques to residuals of 0.064 (2161 'observed' reflections) for (8), 0.057 (1310) for (9), 0.049 (1295) for (10) and 0.061 (1639) for (11). Crystals of (8) are monoclinic, P21/n, a 8.775(5), b 17.352(9), c 30.985(8)Ǻ, β 93.01(3)°, Z 8. Crystals of (9) which contain carbon disulfide are monoclinic, A2/a, a 21.21(2), b 6.181(4), c 20.35(2) Ǻ, β 102.77(7)°, Z 4. Crystals of (10) are monoclinic, P21/n, a 7.540(2), b 4.392(2), c 14.770(4) Ǻ, β 96.29(2)°, Z 2. Crystals of (11) are monoclinic, P1/n, a 14.820(4), b 15.000(3), c 10.819(4)Ǻ, β 106.02(2)°, Z 4.

Crystal structures of a solvated and unsolvated sulfone cyclic oligomer

1999 ◽  
Vol 32 (1) ◽  
pp. 15-20 ◽  
Author(s):  
J. A. Kaduk ◽  
P. J. Cahill ◽  
L. N. Venkateshwaran
Keyword(s):  
Molecular Weight ◽  
Solid State ◽  
Bisphenol A ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Molecular Conformation ◽  
Stacking Interactions ◽  
Powder Diffraction Data ◽  
Molecular Conformations ◽  
X Ray

The structure of the DMSO (dimethyl sulfoxide) solvate of the macrocyclic [2+2] dimer, 17,17,37,37-tetramethyl-2,12,22,32-tetraoxa-7,27-dithianonacyclo[36.2.2.2^{3,6}.-2^{8,11}.2^{13,16} .2^{18,21} .2^{23,26} .2^{28,31} .2^{33,36} ]hexapentaconta-3,5,8,-10,13,15,18,20,23,25,28,30,33,35,38,40,41,43,45,47,49,51,53,55-tetracosaene 7,7,27,27-tetraoxide, formed from 4,\!4'-dichlorodiphenyl sulfone and bisphenol-A has been determined by single-crystal techniques and the structure of the unsolvated dimer refined using X-ray powder diffraction data. The molecular conformations are similar and phenyl–phenyl stacking interactions are apparently important in determining the molecular conformation in the solid state. {\rm C_{54}H_{44}O_8S_2} .{\rm C_2H_6OS} (1)cyclo-[p\hbox{-}{\rm C_6H_4)SO_2(}p\hbox{-}{\rm C_6H_4)O(}p{\rm \hbox{-}C_6H_4){\rm C(CH_3)_2(}p{\rm \hbox{-} {\rm C_6H_4)O]_2}.{\rm C_2H_6OS}: molecular weight 963.2, monoclinic, P2_1/c,a=9.702  (2), b=18.623  (3), c=13.676  (2) Å, \beta =91.18 (1)^\circ , V=2470.5  (7) Å^3,Z=2 .{\rm C_{54}H_{44}O_8S_2} (2),cyclo-[(p{\rm \hbox{-} C_6H_4)SO_2(}p{\rm \hbox{-} {\rm C_6H_4)O(}p{\rm \hbox{-} C_6H_4)C(CH_3)_2(}p{\rm \hbox{-} {\rm C_6H_4)O]_2} : molecular weight 885.06, monoclinic, P2_1/c , a=9.5703  (15), b=18.7582  (18), c=13.3945  (12) Å, \beta =92.684 (11)^\circ , V=2402.0  (5) Å^3,Z=2 .

scholarly journals Crystal Structure of Burgess Inner Salts and their Hydrolyzed Ammonium Sulfaminates

2019 ◽  
Vol 72 (11) ◽  
pp. 867 ◽  
Author(s):  
Anthony J. Arduengo III ◽  
Yosuke Uchiyama ◽  
David A. Dixon ◽  
Monica Vasiliu
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Crystal Structures ◽  
Ethyl Ester ◽  
Crystallographic Analysis ◽  
Water Soluble ◽  
X Ray ◽  
Dative Bond ◽  
Solid State Structures

The solid-state structures of the Burgess reagent, and its analogous ethyl ester reveal structures indicative of triethylamine solvated sulfonyl imides rather than the more commonly depicted triethylammonium sulfonyl amidate. The existence of a reversibly formed hydrate of Burgess reagent is not supported by present studies, but rather a hydrosylate that does not revert to the Burgess reagent with gentle warming under vacuum was isolated and characterised. Structures of the hydrosylates from both the methyl- and ethyl-amidate esters were determined from X-ray crystallographic analysis and are reported. The crystal structures of the Burgess inner salts exhibit geometries at the sulfur atoms that are intermediate between a planar O2S=NCO2R unit and tetrahedral 4-coordinate sulfur centres that would be expected from a strong single (dative) bond between the triethylamine nitrogen and sulfur. The hydrolysed ammonium sulfaminates are water soluble intermolecular salts composed of triethylammonium ions, Et3NH+, and N-(alkoxycarbonyl)sulfaminate, O(−)SO2NHCO2R {R=CH3 or C2H5}.

On the molecular geometry of 1,2-Di(9-anthryl)ethanes. Crystal structures of two crystalline modifications of 1,2-Bis(10-acetoxy-9-anthryl)ethane

1982 ◽  
Vol 35 (11) ◽  
pp. 2357 ◽  
Author(s):  
H Becker ◽  
SR Hall ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Molecular Conformation ◽  
Molecular Geometry ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
Molecular Conformations ◽  
X Ray ◽  
Β Phase ◽  
Α Phase

In order to define molecular conformations, the crystal structures of two crystalline phases of 1,2- bis(10-acetoxy-9-anthryl)ethane have been determined by single-crystal X-ray diffraction methods at 295 K. Both phases are monoclinic, P21/c. For the 'α'-phase, a 7.609(2), b 14.469(3), c 11.358(3) � β, 96.39(2)�, Z 2. The final residual was 0.034 for 1341 'observed' reflections; the molecule is centrosymmetric about a crystallographic inversion centre. For the 'β'-phase, a 31.264(15), b 5.248(3), c 15.718(6) �,β 97.84(3)�, Z 4, the final residual was 0.052 for 972 'observed' reflections. In this structure two independent, centrosymmetric molecules are found. In both α- and β-form, the molecular conformation is thus 'stretched' rather than 'eclipsed'. The packing patterns of the two modifications have been correlated with their crystal luminescence properties.

Bis(1-phenyl-1-propyne) complexes of tungsten(II): crystal structures of [WI2(CO)(NCR)(η2-MeC2Ph)2] (R = Me, Et, or Ph)

2001 ◽  
Vol 79 (3) ◽  
pp. 263-271
Author(s):  
Paul K Baker ◽  
Michael GB Drew ◽  
Deborah S Evans
Keyword(s):  
Carbon Monoxide ◽  
Solid State ◽  
Crystal Structures ◽  
Octahedral Geometry ◽  
X Ray ◽  
X Ray Crystallography ◽  
Alkyne Complexes ◽  
First Time

Reaction of [WI2(CO)3(NCMe)2] with two equivalents of 1-phenyl-1-propyne (MeC2Ph) in CH2Cl2, and in the absence of light, gave the bis(1-phenyl-1-propyne) complex [WI2(CO)(NCMe)(η2-MeC2Ph)2] (1) in 77% yield. Treatment of equimolar quantities of 1 and NCR (R = Et, i-Pr, t-Bu, Ph) in CH2Cl2 afforded the nitrile-exchanged products, [WI2(CO)(NCR)(η2-MeC2Ph)2] (2-5) (R = Et (2), i-Pr (3), t-Bu (4), Ph (5)). Complexes 1, 2, and 5 were structurally characterized by X-ray crystallography. All three structures have the same pseudo-octahedral geometry, with the equatorial sites being occupied by cis and parallel alkyne groups, which are trans to the cis-iodo groups. The trans carbon monoxide and acetonitrile ligands occupy the axial sites. In structures 1 and 2, the methyl and phenyl substituents of the 1-phenyl-1-propyne ligands are cis to each other, whereas for the bulkier NCPh complex (5), the methyl and phenyl groups are trans to one another. This is the first time that this arrangement has been observed in the solid state in bis(alkyne) complexes of this type.Key words: bis(1-phenyl-1-propyne), carbonyl, nitrile, diiodo, tungsten(II), crystal structures.

scholarly journals NOTIZEN. Weitere Verbindungen vom Typ A3NO3: K3NO3 und Rb3NO3 / Further Compounds Typ A3NO3: K3NO3 and Rb3NO3

1980 ◽  
Vol 35 (2) ◽  
pp. 237-238 ◽  
Author(s):  
Martin Jansen
Keyword(s):  
Solid State ◽  
Crystal Structures ◽  
Solid State Reaction ◽  
X Ray

Abstract K3NO3 and RbsNO3 were prepared by solid state reaction of equimolar mixtures of K2O/KNO2 and Rb20/RbN02, respectively. According to X-ray powder photographs their crystal structures are derived from the perovs-kite structure. K3NO3 is isostructural with Na3NO3 (a = 521.7 pm, Z = 1), Rb3NO3 represents a tetragonally distorted variant with a = 770.5, c = 550.8 pm and Z = 2.

scholarly journals Structures of mono-unsaturated triacylglycerols. IV. The highest melting β′-2 polymorphs of trans-mono-unsaturated triacylglycerols and related saturated TAGs and their polymorphic stability

2008 ◽  
Vol 64 (2) ◽  
pp. 249-259 ◽  
Author(s):  
Jan B. van Mechelen ◽  
Rene Peschar ◽  
Henk Schenk
Keyword(s):  
Powder Diffraction Data ◽  
Asymmetric Unit ◽  
Double Chain ◽  
Molecular Conformations ◽  
X Ray ◽  
Acyl Chains ◽  
Independent Molecules ◽  
The Difference ◽  
Polymorphic Stability ◽  
Prime 2

The β_1^{\prime}-2 crystal structures of a series of mixed-chain saturated and trans-mono-unsaturated triacylglycerols containing palmitoyl, stearoyl and elaidoyl acyl chains have been solved from high-resolution powder diffraction data, from synchrotron as well as laboratory X-ray sources. The structures crystallized in the space group I2 with two independent molecules forming a dimer in the asymmetric unit, and packed in double-chain length layers. Unlike the corresponding β-2 structures the solved β_1^{\prime}-2 structures have different molecular conformations for the symmetric and the asymmetric mixed triacylglycerols, both with the sn-2 chain in a leg position of the chair-shaped conformation. A transformation to the β-2 structure with the sn-2 chain in the back position is complicated and unlikely to take place in the solid state. A novel β′-2 polymorph of PSS has been crystallized and its structure has been solved. The melting point (239 K) of this so-called β_0^{\prime}-2 polymorph is 2 K above that of the β_1^{\prime}-2 polymorph and almost equal to that of the β-2 polymorph of PSS. The difference in packing of the β_0^{\prime}-2 versus β_1^{\prime}-2 structure explains the slow β_1^{\prime}-2 to β_0^{\prime}-2 phase transition. The transition is strikingly similar to the β2-3 to β1-3 transition in cis-mono-unsaturated triacylglycerols.

Experimental and computational structural study of two hindered aminoanthraquinones in crystals and solutions

2000 ◽  
Vol 215 (9) ◽  
Author(s):  
A.V. Yatsenko ◽  
K.A. Paseshnichenko ◽  
S.I. Popov
Keyword(s):  
Solid State ◽  
Single Crystal ◽  
Electronic Spectra ◽  
Molecular Structures ◽  
Amino Group ◽  
Single Crystal Diffraction ◽  
Molecular Conformations ◽  
X Ray ◽  
Crystal And Molecular Structures ◽  
Visible Spectra

The crystal and molecular structures of 2-methyl-1-methylamino-anthraquinone (I) and 1-methylphenylamino-anthraquinone (II) were studied by the X-ray single-crystal diffraction and the visible spectra of crystalline specimens and their solutions were recorded. The molecule I is closely planar, whereas in the molecule II the amino group is 58° rotated out of the plane of the anthraquinone skeleton. In both structures the molecules pack in stacks. The comparison of experimental and calculated (on the DFT and AM1 levels) molecular structures, together with the comparison of experimental and INDO/S-calculated electronic spectra, give the evidence that molecular conformations (especially for II) change upon transfer from the solid state to solutions, and the π-delocalisation throughout the whole molecule enhances in the solid state.

scholarly journals Ab initio computation for solid-state 31P NMR of inorganic phosphates: revisiting X-ray structures

2019 ◽  
Vol 21 (19) ◽  
pp. 10070-10074 ◽  
Author(s):  
Kartik Pilar ◽  
Zeyu Deng ◽  
Molleigh B. Preefer ◽  
Joya A. Cooley ◽  
Raphaële Clément ◽  
...  
Keyword(s):  
Solid State ◽  
Chemical Shift ◽  
Ab Initio ◽  
Crystal Structures ◽  
31P Nmr ◽  
Geometry Optimization ◽  
Chemical Shift Tensors ◽  
X Ray ◽  
Ab Initio Computation ◽  
Inorganic Phosphates

The complete 31P NMR chemical shift tensors for 22 inorganic phosphates obtained from ab initio computation are found to correspond closely to experimentally obtained parameters. The cases where correspondence is significantly improved upon geometry optimization point to the crystal structures requiring correction.

scholarly journals 1-[N-Methyl-N-(Phenyl)amino]-3- (4-Methylphenyl)Thiourea

Molbank ◽  
10.3390/m1052 ◽  
2019 ◽  
Vol 2019 (1) ◽  
pp. M1052 ◽  
Author(s):  
Chien Yeo ◽  
Edward Tiekink
Keyword(s):  
Hydrogen Bond ◽  
Solid State ◽  
Hydrogen Bonds ◽  
Single Crystal ◽  
Elemental Analysis ◽  
Title Compound ◽  
Molecular Conformation ◽  
Phenyl Hydrazine ◽  
X Ray ◽  
X Ray Crystallography

The title compound, 1-[N-methyl-N-(phenyl)amino]-3-(4-methylphenyl)thiourea (1), was synthesized by the reaction of 1-methyl-1-phenyl hydrazine and 4-tolyl isothiocyanate, and was characterized by spectroscopy (1H and 13C{1H} NMR, IR, and UV), elemental analysis as well as by single crystal X-ray crystallography. In the solid state, the molecule exists as the thioamide tautomer and features an anti-disposition of the thioamide–N–H atoms; an intramolecular N–H⋯N hydrogen bond is noted. The molecular conformation resembles that of the letter L. In the molecular packing, thioamide-N1–H⋯S1(thione) hydrogen bonds lead to centrosymmetric eight-membered {⋯HNCS}2 synthons. The dimers are assembled into a supramolecular layer in the bc-plane by phenyl- and methyl-C–H⋯π(phenyl) interactions.

Sign in / Sign up

Export Citation Format

Share Document