SPIN TRAPPING BY USE OF NITROSO COMPOUNDS. III. PHENOXAZlNE-N-OXYL PRODUCED FROM THE PHENOXY RADICAL BY SPIN TRAPPING

1972 ◽  
Vol 1 (2) ◽  
pp. 115-118 ◽  
Author(s):  
Shigeru Terabe ◽  
Kazuo Kuruma ◽  
Ryusei Konaka
Keyword(s):  
Spin Trapping ◽  
Nitroso Compounds ◽  
Phenoxy Radical

Spin trapping by use of nitrosodurene and its derivatives

1982 ◽  
Vol 60 (12) ◽  
pp. 1532-1541 ◽  
Author(s):  
Ryusei Konaka ◽  
Shigeru Terabe ◽  
Taiichi Mizuta ◽  
Shigeru Sakata
Keyword(s):  
Hydrogen Peroxide ◽  
Esr Spectra ◽  
Spin Trapping ◽  
Nitroso Compounds ◽  
Spin Adduct ◽  
Spin Traps ◽  
Spectral Pattern ◽  
Alkyl Radicals ◽  
Alkyl Hydroperoxides ◽  
Tert Butyl Hydroperoxide

In spin trapping the N-methyl-N-phenylaminomethyl radical with nitrosodurene, an esr spectmm exhibiting line width alternation was observed despite the normal spectral pattern found with the use of nitroso-tert-butane. Nitrosodurene derivatives, N-duryl nitrone and methyl N-duryl nitrone, have been revealed to be other excellent spin traps for the N-, 0-, and S-centered radicals. Spin adducts of these radicals, which can be independently prepared by spin trapping with nitrosodurene, are stable and can be easily discriminated by large differences in β-hydrogen splittings or characteristic patterns. Methyl N-duryl nitrone reacted with tert-butyl hydroperoxide to give a spin adduct which could be clearly distinguished in the esr spectra from the tert-butoxy adducts prepared independently from other sources. Accordingly, it seems to be the tert-butylperoxy adduct. Similarly, hydrogen peroxide gave a different spectrum from the hydroxy adducts. Alkyl hydroperoxides caused molecule-induced homolysis with the nitroso compounds to produce alkoxy adducts of the respective nitroso compounds. Some phenyl and duryl alkoxy nitroxides undergo decomposition to give alkyl radicals which were trapped by the nitroso compounds.

Spin-trapping in early and some recent nitroso chemistry

1982 ◽  
Vol 60 (12) ◽  
pp. 1602-1609 ◽  
Author(s):  
Th. J de Boer
Keyword(s):  
Radical Reaction ◽  
Radical Scavenging ◽  
Esr Spectra ◽  
Spin Trapping ◽  
Nitroso Compounds ◽  
Organic Radical ◽  
Organometallic Reagents ◽  
Alkyl Nitrites ◽  
Radical Scavenging Properties ◽  
High Yields

The radical scavenging properties of nitroso compounds were discovered accidentally during investigations of photochemical nitrosation of hydrocarbons with alkyl nitrites. Depending on the nature of substrates and nitrosating agent, various nitroxides can be generated. Identification of these nitroxides by their esr spectra has triggered the development of the spin-trapping technique which has been useful in the elucidation of many organic radical reaction mechanisms. Recent studies have shown that the behavior of nitrosocyclopropanes and α-chloro-nitroso alkanes is unorthodox upon irradiation. Dark reactions of α-chloro-nitroso alkanes with Grignard reagents lead to nitrones by a polar mechanism and to oximes by electron transfer. In the latter case high yields of hydrocarbon dimers are sometimes obtained from the Grignard and other organometallic reagents, despite the presence of nitroso compounds. In the postulated reaction mechanism dimers and higher associates from the organometallic reagent play an essential role.

From early spin-trapping experiments to acyl nitroxide chemistry: synthesis of and spin trapping with a water-soluble nitrosopyrazole derivative

1982 ◽  
Vol 60 (12) ◽  
pp. 1587-1593 ◽  
Author(s):  
M John Perkins ◽  
Harparkash Kaur
Keyword(s):  
Spin Trap ◽  
Preliminary Investigation ◽  
Spin Trapping ◽  
Water Soluble ◽  
Nitroso Compounds ◽  
Nitroxide Radicals ◽  
Personal View ◽  
Spin Traps ◽  
Subsequent Investigation

A personal view of early experiments which led to the use of C-nitroso-compounds as spin traps is presented, and it is shown how these experiments resulted in the first isolation, and subsequent investigation, of acyl nitroxide radicals: the use of 1-methyl-4-nitroso-3,5-diphenylpyrazole as a spin trap, and the preparation and preliminary investigation of its water-soluble analogue (1) are described.

Lyoluminescence and spin trapping

1982 ◽  
Vol 60 (12) ◽  
pp. 1549-1559 ◽  
Author(s):  
Kamil V Ettinger ◽  
Alexander R Forrester ◽  
Charles H Hunter
Keyword(s):  
Spin Trap ◽  
Light Yield ◽  
Spin Trapping ◽  
Water Soluble ◽  
Peroxyl Radicals ◽  
Nitroso Compounds ◽  
Γ Irradiation ◽  
Alkyl Radicals ◽  
Emitting Species ◽  
Aromatic Nitroso Compounds

The chemical origin of lyoluminescence has been probed using spin trapping techniques. Radicals derived from amino acids and saccharides by γ-irradiation in the solid state have been identified after trapping with aliphatic and aromatic nitroso compounds. Most of the radicals trapped were secondary alkyl radicals. Reaction of peroxyl radicals derived therefrom are thought to produce the emitting species (excited carbonyl compound and/or singlet oxygen). The effect which thermal annealing of the solids after γ-irradiation has on (a) the concentration of radicals in the solid, (b) the concentration of trapped radicals, and (c) the light yield has been investigated. One new water-soluble spin trap has been prepared.

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