Inhibition of radiation-chemical oxidation of n-octane by stable iminoxyl biradicals

Conclusions The biradicals are effective inhibitors, their inhibiting action increasing with an increase in the distance between the fragments.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 45–48, January, 1977.     

New individual iminoxyl radicals

Conclusions We synthesized a series of individual 2,2,6,6-tetramethyl-1-oxyl-4-piperidyl diamides of carboxylic acids and dicarbamates.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2148–2149, September, 1968.     

New stable iminoxyl radical with a primary hydroxyl group and some of its reactions

Russian Chemical Bulletin -     

Deactivation of electron-excited states of stable nitroxyl biradicals

Conclusions A study was made of the deactivation of the electron-excited states of pyrene and a ruthenium trisbipyridyl complex by stable nitroxyl mono- and biradicals. The deactivation rate constants were measured for nine radicals.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2616–2618, November, 1981.     

Palladium(II) chloride compounds with stable biradicals of imidazoline

Conclusions The first coordination compounds of stable nitroxyl biradical imidazolines have been synthesized. From the spectral data obtained, the paramagnetic ligand 4,4-(ethyleneiminomethyl)di-2, 2,5,5-tetramethyl-3-imidazoline-1-oxyl acts as a tetradentate bridge in a binuclear coordination compound with Pd(II), while the azine ligand 4-formyl-2,2,S,5-tetramethyl-3-imidazoline-1-oxyl acts as a bidentate bridge.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2581–2584, November, 1988.The authors thank E. G. Boguslavskii, I. M. Oglezneva, and V. A. Shipachev for help in obtaining the spectra of the compounds.     

NMR spectra of iminoxyl radicals

NMR spectra of iminoxyls and the corresponding amines are used to calculate the paramagnetic shifts in the free radicals, which are used to calculate the constants a _i for the hyperfine interactions with the protons in the radicals. The a _i for the -protons are negative, while those for the -protons are positive. The constants are discussed in relation to a simple model based on propagation of spin density via bonds by spin polarization and hyperconjugation. The spatial structure of the radicals is also discussed.     

Low-temperature NMR investigation of iminoxyl radicals

By analysis of proton magnetic resonance spectra recorded at 4.2 and 3 K, the isotropic and anisotropic constants for the coupling of the unpaired electron with all the protons were determined for two investigated radicals. On the basis of these results, conclusions were reached on the spin density distribution and on the participation of the unpaired electron in hydrogen bond formation.We express our sincere gratitude to I. F. Shchegolev for useful discussions.