Photochemical cis-trans Isomerization of 2-Substituted 9-(2-Nitroethenyl)anthracenes. X-Ray Structure Analyses of (E)- and (Z)-9-(2-Nitro-2-phenylethenyl)anthracene

1989 ◽  
Vol 42 (4) ◽  
pp. 593 ◽  
Author(s):  
HD Becker ◽  
BW Skelton ◽  
H Sorensen ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Quantum Yields ◽  
X Ray Diffraction ◽  
X Ray ◽  
Photostationary State ◽  
Trans Isomerization ◽  
Photochemical Isomerization

(E)-9-(2-Nitropropeny1)anthracene and (E)-9-(2-nitro-2-phenylethenyl)anthracene have been prepared by piperidine-catalysed condensation of 9-anthraldehyde with nitroethane and nitro(phenyl)methane, respectively. The corresponding (Z)-compounds were obtained by photochemical isomerization, quantum yields of geometrical isomerlzation being measured in cyclohexane, benzene, dichloromethane and ethanol. In virtually all solvents the (Z)-isomers are favoured at the photostationary state. The structures of (E)- and (2)-942- nitro-2-phenylethenyl)anthracene have been established by single-crystal X-ray diffraction studies.

On the Reaction of ortho-Diphenoquinone Valence Isomers with Primary and Secondary Amines. X-Ray Structure Analysis of a 2,3-Dihydro-1H-azepinone and its Photochemical and Oxidative Conversion Products

1979 ◽  
Vol 32 (9) ◽  
pp. 1931 ◽  
Author(s):  
H Becker ◽  
K Gustafsson ◽  
CL Raston ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Secondary Amines ◽  
Reaction Products ◽  
Oxidative Conversion ◽  
X Ray Diffraction ◽  
X Ray ◽  
Primary And Secondary Amines ◽  
Diffraction Structure ◽  
Structure Determinations ◽  
Photochemical Isomerization

Single-crystal X-ray diffraction structure determinations are reported for three reaction products and photoisomers formed from reactions between an o-diphenoquinone valence isomer and primary and secondary amines, namely: 3,5-di-t-butyl-7-(3,5-di-t-butyl-2-hydroxyphenyl)-1-methyl-2,3-dihydro-1H-azepin-2-one (8; R1 = R2 = But, R3 = Me), its photochemical isomerization product 4,6-di-t-butyl-1-(3,5-di-t-butyl-2-hydroxyphenyl)-2-methyl-2-azabicyclo[3,2,0]hept-6-en-3-one (9; R1 = R2 = But, R3 = Me) and 4',5,7-tri-t-butyl-3'-(2,2-dimethylpropionyl)-1'-methylspiro[benzofuran-3(2H)-2'- pyrrolidinel-2,5'-dione (12; R1 = R2 = But, R3 = Me).

Molecular Topology of Linked Anthracenes: X-Ray Structure Analyses of Alkyl Di-9-anthryl-glycolates, 9-Anthryl 9-Anthrylmethyl Ethers and Their Photoisomers

1989 ◽  
Vol 42 (11) ◽  
pp. 1869 ◽  
Author(s):  
HD Becker ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Alder Reaction ◽  
Diels Alder ◽  
Molecular Structures ◽  
Molecular Topology ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diels Alder Reaction ◽  
Photochemical Isomerization ◽  
Spatial Demand

The molecular structures of ethyl di-9-anthrylglycolate (1) and methyl di-9-anthrylglycolate (2), as well as those of three isomerization products of (2), have been established by single-crystal X-ray diffraction studies. In both (1) and (2), the anthracenemoieties are characterized by marked deviations from planarity. The stereospecific course of the thermal and photochemical isomerization of (2) by Diels -Alder reaction is suggested to be governed by the spatial demand of the alkoxycarbonyl group. Base-catalysed isomerization of (2) by migration of 9-anthryl from carbon to oxygen is associated with steric relief.

Single crystal X-ray structure and optical properties of anthraquinone-based dyes

2010 ◽  
Vol 64 (5) ◽  
Author(s):  
Nurcan Kurtoglu ◽  
Mehmet Aslantaş ◽  
Huseyin Zengin ◽  
Ertan Şahin ◽  
Mukerrem Kurtoglu
Keyword(s):  
Optical Properties ◽  
Single Crystal ◽  
Uv Light ◽  
Quantum Yields ◽  
X Ray Diffraction ◽  
Monoclinic System ◽  
Characterization Methods ◽  
Light Emitting ◽  
X Ray ◽  
Anthraquinone Dyes

AbstractThis study focuses on the preparation, single crystal X-ray diffraction, characterization, and optical properties of some anthraquinone-based dyes. The anthraquinone-based antimicrobial dye N-{2-[(9,10-dioxo-9,10-dihydroanthracen-1-yl)amino]-2-oxoethyl}-N,N-dimethylbutan-1-aminium chloride monohydrate (III) was obtained from 1-aminoanthraquinone (I) via 2-chloro-N-(9,10-dioxo-9,10-dihydroanthracen-1-yl)acetamide (II) using known preparation and characterization methods. Single crystal X-ray diffraction analysis of III revealed a monoclinic system, space group P21/n, Z = 4. Photoluminescence properties of anthraquinone dyes I–III were also investigated. These dyes gave an intense emission (λmax = 341 nm) upon the irradiation by UV light and showed photoluminescence quantum yields of 73 %, 66 %, and 61 % with long excited-state lifetimes of 6.87 ns, 6.14 ns, and 5.69 ns, respectively. These anthraquinone dyes are of interest as an organic light emitting material for electroluminescent devices.

Electron Microscopy of Shock Loaded Polycrystalline Beryllium

1974 ◽  
Vol 32 ◽  
pp. 506-507 ◽  
Author(s):  
J. M. Galbraith ◽  
L. E. Murr ◽  
A. L. Stevens
Keyword(s):  
Electron Microscopy ◽  
Wave Propagation ◽  
Structural Change ◽  
Single Crystal ◽  
Diffraction Pattern ◽  
Shock Loading ◽  
Slip Systems ◽  
Compression Tests ◽  
X Ray Diffraction ◽  
X Ray

Uniaxial compression tests and hydrostatic tests at pressures up to 27 kbars have been performed to determine operating slip systems in single crystal and polycrystal1ine beryllium. A recent study has been made of wave propagation in single crystal beryllium by shock loading to selectively activate various slip systems, and this has been followed by a study of wave propagation and spallation in textured, polycrystal1ine beryllium. An alteration in the X-ray diffraction pattern has been noted after shock loading, but this alteration has not yet been correlated with any structural change occurring during shock loading of polycrystal1ine beryllium.This study is being conducted in an effort to characterize the effects of shock loading on textured, polycrystal1ine beryllium. Samples were fabricated from a billet of Kawecki-Berylco hot pressed HP-10 beryllium.

Crystal structure of an inclusion complex between chiral monoaza-15-crown-5 and S(–)-1-phenyl-ethyl ammonium percholorate

2003 ◽  
Vol 218 (5) ◽  
Author(s):  
Süheyla Özbey ◽  
F. B. Kaynak ◽  
M. Toğrul ◽  
N. Demirel ◽  
H. Hoşgören
Keyword(s):  
Crystal Structure ◽  
Inclusion Complex ◽  
Single Crystal ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
New Type

AbstractA new type of inclusion complex, S(–)-1 phenyl ethyl ammonium percholorate complex of R-(–)-2-ethyl - N - benzyl - 4, 7, 10, 13 - tetraoxa -1- azacyclopentadecane, has been prepared and studied by NMR, IR and single crystal X-ray diffraction techniques. The compound crystallizes in space group

Single Crystal X-Ray Diffraction in Structure Elucidation of Arborinine from Glycosmis pentaphylla

2017 ◽  
Vol 7 (3) ◽  
Author(s):  
Moon Moon Das ◽  
Dibakar Chandra Deka ◽  
Ranjit Thakuria
Keyword(s):  
Single Crystal ◽  
Structure Elucidation ◽  
X Ray Diffraction ◽  
X Ray

Unusual Rearrangement of Naphthalene in the Synthesis of a Novel B8-B8-Bridged Derivative in the [(1,2-C2B9H11)2-3-Co]- Series. X-Ray Structure and 11B NMR Spectra of [8,8'-μ-(CH2-C9H6)-(1,2-C2B9H10)2-3-Co]- (CH3)4N+

1997 ◽  
Vol 62 (5) ◽  
pp. 746-751 ◽  
Author(s):  
Andreas Franken ◽  
Jaromír Plešek ◽  
Christiane Nachtigal
Keyword(s):  
Nmr Spectroscopy ◽  
Single Crystal ◽  
Nucleophilic Substitution ◽  
Nmr Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Unusual Rearrangement ◽  
Multinuclear Nmr Spectroscopy ◽  
11B Nmr ◽  
Isolated Compound

On treatment of the [(1,2-C2B9H11)2Co]- ion with naphthalene in presence of AlCl3 a remarkably bridged [8,8'-μ-(CH2-C9H6)-(1,2-C2B9H10)2-3-Co]- ion is obtained as a single isolated compound. The triatomic -CH2-C9H6- bridge is derived from the rearranged naphthalene nucleus. The mechanism of this reaction is obscure but it does resemble the "Electrophile-Induced Nucleophilic Substitution" reported earlier. The structure of the compound was established by multinuclear NMR spectroscopy and by single crystal X-ray diffraction.

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