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Phosphorescence autoxidations

Beside the phosphorescence of the carbonyl compounds produced in autoxidation reactions, there is some additional luminescence by singlet oxygen 14,43) it js sometimes difficult to differentiate between emission and the longer-wavelength part of the ketone phosphorescence 38>. [Pg.76]

Radical 80 has been prepared as its perchlorate salt by anodic oxidation in ethyl acetate in the presence of hthium perchlorate. The reactivity toward nucleophiles of material so prepared was investigated nitrite and nitrate ions give 2-nitrodibenzo[l,4]dioxin although the mechanisms of the reactions are not clear. Pyridine gives 7V-(2-dibenzo[l,4]dioxinyl)pyridinium ion (84). Other nucleophiles acted as electron donors and largely reduced 80 back to the parent heterocycle they included amines, cyanide ion and water. In an earlier study, the reaction of 80 with water had been examined and the ultimate formation of catechol via dibenzo[l,4]dioxin-2,3-dione was inferred. The cation-radical (80) has been found to accelerate the anisylation of thianthrene cation-radical (Section lII,C,4,b) it has been found to participate in an electrochemiluminescence system with benzo-phenone involving phosphorescence of the latter in a fluid system, and it has been used in a study of relative diffusion coefficients of aromatic cations which shows that it is justified to equate voltammetric potentials for these species with formal thermodynamic redox potentials. The dibenzo[l,4]dioxin semiquinone 85 has been found to result from the alkaline autoxidation of catechol the same species may well be in-... [Pg.66]

In polymers undergoing autoxidation, chemiluminescence is the weak, spontaneous emission of light dependent on sample heating. Fluorescence is radiation caused be a transition in an atom from absorption of light. Fluorescence is characterized differently than phosphorescence in that the transidon is from a higher energy level to the ground state. [Pg.2962]


See other pages where Phosphorescence autoxidations is mentioned: [Pg.104]    [Pg.75]    [Pg.710]    [Pg.66]    [Pg.358]    [Pg.54]    [Pg.182]   
See also in sourсe #XX -- [ Pg.24 ]




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