Synthesis of some hetrocyclic radicals of the iminoxyl class

Kokhanov, Yu. V.; Rozantsev, É. G.; Ntkolenko, L. N.; Максимова, Л. А.

doi:10.1007/bf00481109

Cited by 3 publications

(4 citation statements)

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“…The educt 4-amino-2,2,6,6-tetramethyl-1-piperidinyloxyl and the precursor 4-[(2-chloroacetyl)amino]-2,2,6,6-tetramethyl-1-piperidinyloxyl were synthesized using standard literature procedures. [13][14][15] The second and third steps of the reaction were prepared as follows. The ion exchange intercalation was carried out by stirring the clay in an aqueous solution of the radical salts for 4 hours at room temperature.…”

Section: Materials and Synthesismentioning

confidence: 99%

Synthesis and characterization of inorganic–organic hybrid materials based on the intercalation of stable organic radicals into a fluoromica clay

et al. 2013

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Hybrid materials, in which stable organic radical cations are intercalated into layered inorganic host materials, can be successfully synthesized via an ion exchange reaction in a layered fluoromica clay, to yield recyclable heterogeneous catalysts for oxidation of various alcohols. We have conducted systematic synthetic and structural studies on the intercalation of the radical cations 4-(diethylmethylammonium)-2,2,6,6-tetramethylpiperidin-1-oxyl (DEMTEP), 1-[2-(4-amino-2,2,6,6-tetramethyl-1-piperidinyloxyl)-2-oxoethyl]-1'-methyl-4,4'-bipyridinium (VIOTEP), and 2-(3-N-methylpyridinium)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-1-oxyl-3-N-oxide (m-MPYNN) into a synthetic fluoromica clay named Somasif® ME 100, Na(2x)Mg(3.0-x)Si4O10(F(y)OH(1-y))2 (x = 0.33, y = 0.98). The guest-host interactions in these intercalation compounds have been characterized by X-ray powder diffraction and solid-state NMR of the constituent nuclei ((23)Na, (19)F, and (29)Si) of the Somasif structure. The intercalation process can be conveniently monitored using (23)Na MAS-NMR. Guest-guest interactions have been probed by magnetic susceptibility measurements as well as EPR and (1)H MAS NMR experiments. The (1)H MAS-NMR line widths and chemical shifts probe modifications in the electron spin density distributions and/or intermolecular interactions between the electron spins of the guest species. Despite these indications of weakly interacting spins, magnetic susceptibility measurements are consistent with the near-absence of cooperative magnetism. The VIOTEP and DEMTEP inclusion compounds demonstrate catalytic activity for the oxidation of benzyl alcohol, using NaOCl as a co-oxidant. Although the radical ion species is partially leached out under these conditions (ionic exchange with Na(+) in solution) the catalytic activity remains for up to 40 subsequent cycles. Fully leached materials can be regenerated by catalyst re-loading and this process can be conveniently monitored by X-band EPR spectroscopy.

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Section: Materials and Synthesismentioning

confidence: 99%

Synthesis and characterization of inorganic–organic hybrid materials based on the intercalation of stable organic radicals into a fluoromica clay

et al. 2013

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“…The anodic reaction occurring in this process was the slow oxidation of graphite surface to C COOH, CO and CO 2 . Kokhanov [25] and Krishtalik and co-workers [26] studied the kinetic aspects of these reactions. Their investigations were carried out mostly in phosphate electrolytes where intercalation effects were small and the water (or hydroxyl ion) oxidation reaction predominated.…”

Section: Influence Of Impuritiesmentioning

confidence: 99%

“…The corrosion of carbon was studied by many authors [20][21][22][23][24][25][26][27][28]. Kinoshita and Bett [20,21] reported that the formation of a surface oxide and evolution of carbon dioxide (CO 2 ) occurred during the electrochemical oxidation of different carbons in H 3 PO 4 solution at temperatures up to 135 • C. A protective oxide (graphite oxide) and a surface oxide were found to form when the anodic current was imposed during the electrolysis of carbon electrodes in HCl [22].…”

Section: Introductionmentioning

confidence: 99%

Classic and local analysis of corrosion behaviour of graphite and stainless steels in polluted phosphoric acid

Iken¹,

Basseguy

Guenbour³

et al. 2007

Electrochimica Acta

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In phosphoric acid solution (40% H 3 PO 4 ), the corrosion behaviour of graphite and stainless steels was studied by the use of different electrochemical methods, namely polarization curve analysis, electrochemical impedance spectroscopy (EIS) and scanning vibrating electrode technique (SVET). The combined effect of chemical impurities and the increase of medium temperature was studied to approach the real conditions in the process of phosphoric acid manufacturing. It was found that the current density measured by polarization curves increased with the presence of chloride and sulphate ions in the acid solution whatever the tested material. Compared to stainless steels, graphite had the best corrosion resistance in polluted phosphoric acid. However, for graphite the increase of temperature from 20 to 80• C induced an increase of the corrosion rate and potential and a decrease of the resistance confirmed by EIS results. Subsequently, local currents were detected at the surface of the sample by using the scanning vibrating electrode technique. From the data obtained, graphite surface manifested a distinctive behaviour from that of stainless steels. A generalized corrosion was occurred on graphite whereas a localized corrosion was observed for stainless steels. These results show a clear interest of graphite as component material in some of the equipments of the phosphoric acid industry.

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“…The design of organometallic derivatives of nitroxide radicals [ 1 , 2 , 3 ] has a high potential for the development of new organic synthesis principles and the study of the mechanisms of catalytic reactions [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ] as well as for the creation of polyfunctional magnetoactive materials exhibiting diverse intra- and intermolecular interactions and spin-exchange coupling [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ,…”

Section: Introductionmentioning

confidence: 99%

2-Imidazoline Nitroxide Derivatives of Cymantrene

et al. 2022

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The 2-imidazoline nitroxide derivatives of cymantrene—2-(η5-cyclopentadienyl)tricarbonylmanganese(I)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl (NNMn) and 2-(η5-cyclopentadienyl)tricarbonylmanganese(I)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-1-oxyl (INMn) were synthesized. It was shown that NNMn and INMn exhibit a sufficiently high kinetic stability both in solids and in solutions under normal conditions. Their structural characteristics, magnetic properties and electrochemical behavior are close to Re(I) analogs. This opens the prospect of using paramagnetic cymantrenes as prototypes in the design of Re(I) half-sandwiched derivatives for theranostics, where therapy is combined with diagnostics by magnetic resonance imaging due to the contrast properties of nitroxide radicals.

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Synthesis of some hetrocyclic radicals of the iminoxyl class

Cited by 3 publications

References 0 publications

Synthesis and characterization of inorganic–organic hybrid materials based on the intercalation of stable organic radicals into a fluoromica clay

Synthesis and characterization of inorganic–organic hybrid materials based on the intercalation of stable organic radicals into a fluoromica clay

Classic and local analysis of corrosion behaviour of graphite and stainless steels in polluted phosphoric acid

2-Imidazoline Nitroxide Derivatives of Cymantrene

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