42473-26-7Relevant articles and documents
The chain-breaking antioxidant activity of phenolic compounds with different numbers of O-H groups as determined during the oxidation of styrene
Tikhonov, Ivan,Roginsky, Vitaly,Pliss, Evgeny
experimental part, p. 92 - 100 (2009/06/28)
The technique based on monitoring oxygen, consumption was applied to test 18 polyphenols (PP) and model phenolics as a chain-breaking antioxidant during the oxidation of styrene initiated by 2,2′-azobis(2,4- dimethylvaleronitril) at 37°C. The chain-breaking capability of PP was characterized by two parameters: the rate constant k1 for the reaction of antioxidants with the peroxy radical produced from styrene and the stoichiometric coefficient of inhibition, f, which shows how many kinetic chains are terminated by one molecule of PP. Rate constants k1 × 105 (in M-1 s-1) were found to be 10 (catechol), 27 (pyrogallol), 34 (3,6-di-tert-Bucatechol), 4.3 (protocatechic acid), 12 (gallic acid), 15 (caffeic acid), 1 increases when going from one to two and three adjacent O-H groups in a benzene ring (catechol and pyrogallol derivatives, respectively). At the same time, two O-H. groups in metaposition in a A-ring of flavonoids actually do not participate in the inhibition. For the majority of PP, f is near to 2 independent of the number of OH groups. The correlation of k1 with the structure of PP and the O-H bond dissociation enthalpy has been discussed.
ESR ANALYSIS OF THE KINETIC ALKALINITY OF PSEUDOEPHEDRINE
Masalimov, A. S.,Nikol'skii, S. N.,Abdykarimova, A. P.,Prokof'ev, A. I.,Muldakhmetov, Z. M.
, p. 1559 - 1562 (2007/10/02)
The kinetics of protonation of pseudoephedrine by 3,6-di-tert-butyl-2-hydroxyphenoxyl have been analyzed by the ESR technique.It was shown that protolysis of the radical produced closed ionic pairs with the pseudoephedrine cation in a dimer state. Keywords: ESR, pseudoephedrine, 3,6-di-tert-butyl-2-hydroxyphenoxyl, ion pairs.
MECHANISM OF THE DEHYDROGENATION OF HYDRAZOBENZENE
Kibizova, A. Yu.,Klimov, E. S.,Bereberova, N. T.,Okhlobystin, O. Yu.
, p. 1037 - 1041 (2007/10/02)
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