Реферат: Kinetics and equilibrium of the acid-catalyzed disproportionation of cyclic nitroxyl radicals R 2NO• to oxoammonium cationsR 2 NO + and hydroxylamines R 2 NOH is defined by redox and acid–base properties of these compounds. In a recent work(J. Phys. Org. Chem. 2014, 27, 114-120), we showed that the kinetic stability of R2NO• in acidic media depends on the basicityof the nitroxyl group. Here, we examined the kinetics of the reverse comproportionation reaction of R2NO+ and R2NOH to R2NO•and found that increasing in –I-effects of substituents greatly reduces the overall equilibrium constant of the reaction K4. Thisoccurs because of both the increase of acidity constants of hydroxyammonium cations K3H+ and the difference between the re-duction potentials of oxoammonium cations ER2NO+/R2NO• and nitroxyl radicals ER2NO•/R2NOH. pH dependences of reduction poten-tials of nitroxyl radicals to hydroxylamines E1/3Σ and bond dissociation energies D(O–H) for hydroxylamines R2NOH in water weredetermined. For a wide variety of piperidine- and pyrrolidine-1-oxyls values of pK3H+ and ER2NO+/R2NO• correlate with each other,as well as with the equilibrium constants K4 and the inductive substituent constants σI. The correlations obtained allow predictionof the acid–base and redox characteristics of redox triads R2NO•–R2NO+–R2NOH.

Библиографическая ссылка: Sen’ V.D. , Tikhonov I.V. , Borodin L.I. , Pliss E.M. , Golubev V.A. , Syroeshkin M.A. , Rusakov A.I.
Kinetics and thermodynamics of reversible disproportionation–comproportionation in redox triad oxoammonium cations – nitroxyl radicals – hydroxylamines
Journal of Physical Organic Chemistry. 2014. V.28. N1. P.17-24. DOI: 10.1002/poc.3392 WOS Scopus OpenAlex

Идентификаторы БД:

Web of science:	WOS:000346789100003
Scopus:	2-s2.0-84920424391
OpenAlex:	W2300732104

Цитирование в БД:

БД	Цитирований
OpenAlex	51
Scopus	48
Web of science	46

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