Synthesis of some organophosphorus compounds: a study of the electron spin resonance spectra of the free radical anions formed by the reactions of 4,4′-bis(diphenylphosphine)biphenyl with alkali metals

1969 ◽  
Vol 47 (24) ◽  
pp. 4679-4684 ◽  
Author(s):  
Mahdy H. Hnoosh ◽  
Ralph A. Zingaro
Keyword(s):  
Electron Spin Resonance ◽  
Electron Spin ◽  
Alkali Metals ◽  
Organophosphorus Compounds ◽  
Reaction Conditions ◽  
Sodium Potassium ◽  
Spin Resonance ◽  
Different Temperatures ◽  
Oxygenated Products

By the halogen–lithium interconversion method, 4,4′-bis(diphenylphosphine)biphenyl (1) was prepared. Under different reaction conditions, mono- and di-oxygenated products were obtained. An attempt to prepare 1 by the Grignard reagent method failed to give the expected product but[Formula: see text]was obtained. Bis(diphenylamine)phenylphosphine was also prepared. Tetraphenyldiphosphine monoxide resulted from an attempt to prepare N-diphenylaminodiphenylphosphine. The mechanism of this reaction is discussed. Infrared spectroscopy, elemental analysis, and activation analysis for the determination of oxygen content were performed for the identification of the above compounds.Reactions of 1 with sodium–potassium alloy in tetrahydrofuran (THF) and 1,2-dimethoxyethane (DME) gave a radical anion which was identified by its electron spin resonance spectra at different temperatures.

Nitroxides as reaction intermediates

1982 ◽  
Vol 60 (12) ◽  
pp. 1414-1420 ◽  
Author(s):  
Hans Gunter Aurich
Keyword(s):  
Electron Spin Resonance ◽  
Electron Spin ◽  
Isopropyl Alcohol ◽  
High Reactivity ◽  
Reaction Intermediates ◽  
Reaction Products ◽  
Nitronyl Nitroxide ◽  
Reaction Conditions ◽  
Spin Resonance ◽  
Secondary Reactions

Vinyl nitroxides 4 are obtained by oxidation of the nitrones 3, as was shown by esr studies and by identification of the reaction products. The formation of 4d–f is even observed in oxidation of the hydroxylamines 1d–f, nitroxides 2d–f and nitrones 3d–f being the intermediates. The high reactivity of the vinyl nitroxides 4 at their β-position is illustrated by the reactions of 4a with various compounds affording the nitroxides 7–10, respectively. Compound 4c reacts with its precursor 3c to give 11, 12, or 13, depending on the reaction conditions. From oxidation of 3a, c, and e the dimerization products 5a, c, and e, respectively, could be isolated. Whereas further oxidation of 5d yields 6d, the acyl nitroxides 14a and c are formed in the oxidation of 5a and c, respectively.The formation of quinone 23 in the reaction of 2-methyl-2-nitrosopropane with potassium tert-butoxide in isopropyl alcohol in the presence of oxygen is discussed. The nitroxide 20 has been detected in the reaction mixture. Imines 24 react with nitrosobenzene giving nitroxides 26. These are further oxidized by nitrosobenzene to afford nitrones 27. Whereas 27a and b could be isolated, 27c and d undergo further reaction yielding the diimines 30c and d along with dinitrone 29.The formation and reactions of imino nitroxides 31 and of the nitronyl nitroxide 41 are discussed. Electron spin resonance studies revealed the high reactivity of the imidazolyl-1,3-dioxides 46 and the imidazolyl-1-oxides 50, which easily form radicals 47–49 and 51, respectively, which are derived from secondary reactions.

Electron-spin-resonance determination of the internal field within the superconductorYBa2Cu3O7

1990 ◽  
Vol 41 (4) ◽  
pp. 2046-2048 ◽  
Author(s):  
Horacio A. Farach ◽  
Eduardo Quagliata ◽  
Taha Mzoughi ◽  
Manuel A. Mesa ◽  
Charles P. Poole ◽  
...  
Keyword(s):  
Electron Spin Resonance ◽  
Electron Spin ◽  
Internal Field ◽  
Spin Resonance

Stable free-radical complexing reagents in applications of electron spin resonance to the determination of metals

1981 ◽  
Vol 128 ◽  
pp. 85-99 ◽  
Author(s):  
V.Yu. Nagy ◽  
M.V. Evstiferov ◽  
O.M. Petrukhin ◽  
L.B. Volodarskii ◽  
Yu.A. Zolotov
Keyword(s):  
Electron Spin Resonance ◽  
Free Radical ◽  
Electron Spin ◽  
Stable Free Radical ◽  
Spin Resonance
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