Nitroxides s. N-Oxide radicals

Nitroxides s. N-Oxide radicals Nitroxy compounds s. Bis-(trifluoromethyl)nitroxy derivatives Nitryl fluoride... 

Early publications on [VO(/3-diketonato)2] have been reviewed.355 More recently, complexes with benzoyl m-nitroacetanilide, benzoyl acetanilide545 and l,l -(l,3-phenylene)-bis(butane-1,3-dione546 have been synthesized. Other [VO(/S-dik)2] adducts have been isolated, for example [VO(acac)2] adducts with a series of pyridine N-oxides547 and several pyridine carboxamides, 48 and [VO(bzac)2] adducts with pyridine, methylamine, isoquinoline and 4-picoline.549 Equilibrium constants of 1 1 and 2 1 adducts of pyrazine with [VO(tfacac)2] have been determined (equation 38).550 In the 2 1 complex, the pyrazine bridge between two equatorial sites of adjacent vanadium atoms promotes a weak exchange interaction. The nitroxide radical 2,2,6,6-tetramethylpiperidinyl N-oxide also forms an adduct with [VO(hfacac)2] in which there is a strong interaction between the electrons on the metal and nitroxide.551... 

The rate constant for the reaction of the aminyl with ROO was reported 6 x 108 dm3 mol-1 s-1 [50], Although the rate is very high in the DPA series, it is lower than the rate of initiation of the chain oxidation. It is so because ROO attacks not only the N-centred radical 42a, but also the rings of the C-centred radicals 42b, c [60], The NO formation has been diminished by the presence of organic acids. The nitroxide arises in die yield about 80% also in ozonation of DPA or its 4,4 -dialkylderivatives [62],... 

Nelson s detailed investigation of one-electron oxidation of bicyclic amines and hydrazines continues CV studies show that /V -diacyl-hydrazines (19)30a and azabicyclooctanes (20a)30b gjVe long-lived radical cations comparison has been made between ease of electron loss and N inversion barriers in (20b) and related N-chloroamines 30c studies of the nitroxides (21) and related compounds show that ff-coupied transmission of positive charge from N to the CO in the radical cation is unimportant. 30d... 

The first fluorocarbon analogue of Fremy s radical [ 0-N(S03 )2] has been synthesized from irifluoronitrosomethane CF3 NO + M HSOs" (aq.) (M = Na or K)-> [CF3-N(0H) S03- M+] (with PbOs) CFa N(6)-S03-M+(aq.) (purple solution) -> (with Ph4As+ Cl ) CF3 N(6) SOs PI14AS+(purple solid), and numerous trifluoromethylated nitroxides have been detected by e.s.r. spectroscopy during the oxidation by trifluoronitrosomethane or potassium permanganate of hydroxylamines produced during work on ene reactions of trifluoronitrosomethane... 

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