Results 171 to 180 of about 10,849 (224)

Electronic Structure of Persistent Radicals:  Nitroxides

The Journal of Organic Chemistry, 2004
The molecular and electronic structures of 10 free nitroxide radicals have been investigated by HeI/HeII photoelectron spectroscopy (UPS), DFT calculations, and comparison with the spectra of related compounds. We observe that the electronic structure of the nitroxide group is unaffected by substitution except in a carbonyl derivative where nitroxide ...
Novak, I., Harrison, L.J., Kovac, B., Pratt, L.M.   +3 more
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Stereochemistry of Phenylα-Nitronyl Nitroxide Radicals

Chemistry - A European Journal, 2000
An extensive investigation of the conformations adopted by the family of phenyl alpha-nitronyl nitroxides has been carried out. A database containing 110 crystal structures was used in a statistical study of the solid-state geometries and conformations of these radicals.
Maria Minguet, David B. Amabilino, Joan Cirujeda, Klaus Wurst, Ignasi Mata, Elies Molins, Juan J. Novoa, Jaume Veciana   +7 more
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Azobenzene Derivatives Carrying a Nitroxide Radical

The Journal of Organic Chemistry, 2007
Several trans-azobenzene derivatives carrying a nitroxide (aminoxyl) radical (2a, 6a-12a) were prepared, and their photoisomerization reactions to the corresponding cis-isomers were investigated. Although no fruitful results could be obtained for the photoisomerizations of the derivatives with para-subsituents (9a-12a), the unsubstututed derivatives at
Shin'ichi, Nakatsuji, Masahiro, Fujino, Satoko, Hasegawa, Hiroki, Akutsu, Jun-ichi, Yamada, Vladimir S, Gurman, Andrey, Kh Vorobiev   +6 more
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Alkylpentacyanocobalt nitroxide and primary alkyl nitroxide radical-anions

Journal of the Chemical Society, Chemical Communications, 1972
Monomeric aliphatic nitroso-compounds react with {Co(CN)5}3– in aqueous/alcoholic solutions to give radical-anions {(NC)5Co–N(Alk)–O·}3– and/or (Alk–N–O–) which can be characterised by e.s.r.; they have lifetimes of the order of minutes.
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A convenient nitroxide radical synthesis

Journal of the Chemical Society, Chemical Communications, 1972
A number of suitably substituted δIµ-unsaturated nitroso-compounds have been prepared and cyclised to pyrrolidino-nitroxide radicals.
W. B. Motherwell, J. S. Roberts
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Electrode reactions of nitroxide radicals

Journal of Electroanalytical Chemistry, 1992
Abstract The redox reaction Nox. ← Nox+ + e− of the 8 free nitroxide radicals, which are derivatives of 2,2,6,6-tetramethylpiperidine-1-oxyl, were investigated in acetonitrile solutions (c = 2.5 × 10−4 − 1 × 10−2 mol dm−3) on a gold working electrode.
Paweł Krzyczmonik, Henryk Scholl
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Nitroxide Radical–Metal Chelate Interactions

The Journal of Chemical Physics, 1970
We have investigated the interaction of some nitroxide radicals with a series of transition-metal acetyl-acetonate complexes by monitoring the linewidth of peaks in the ESR spectra of the radicals as a function of chelate concentration. The effect of the chelates on the NMR spectra of some diamagnetic materials was also investigated. The linewidths are
David Wilbur, Robert Kreilick
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Nitroxide radicals from substituted ureas

Journal of the Chemical Society B: Physical Organic, 1969
Nitroxides with aryl and anilinocarbonyl groups are reported. Hyperfine structure due to the aryl protons and nitroxide groups only are observed, though the carbonyl group affects the redistribution of spin density when ortho-substituents sterically reduce the delocalisation on to the aromatic ring.
V. S. Griffiths, G. R. Parlett
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α-Nitronyl Nitroxide Cation Radicals

Chemistry Letters, 1991
Abstract X-Ray crystal analysis and magnetic measurements have been carried out on the first cation radical salt of α-nitronyl nitroxide, 2-(4-N-R-pyridinium)-4,4,5,5-tetrametyl-4,5-dihydro-1H-imidazol-1-oxyl 3-N-oxide iodide (with R = methyl (1) and ethyl), suggesting the separation between the spin and the charge density population ...
Kunio Awaga, Tamotsu Inabe, Umpei Nagashima, Takayoshi Nakamura, Mutsuyoshi Matsumoto, Yasujiro Kawabata, Yusei Maruyama   +6 more
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Nitroxide radicals. Part II. The oxidation of phenols to quinones by stable nitroxide radicals

Journal of the Chemical Society C: Organic, 1966
The stable radicals diphenyl- and 4,4′-dinitrodiphenyl-nitroxide, Benfield and Kenyon's radical, and porphyrexide, oxidise phenols to quinones, 4,4′-dinitrodiphenylnitroxide being of the most practical value.
A. R. Forrester, R. H. Thomson
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