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Information × Registration Number 0220U101577, 0117U002361 , R & D reports Title The proton-coupled electron transfer in homolytic reactions of phenols in aqueous and aqueous-organic media popup.stage_title Head Shendrik Alexandr M., Доктор хімічних наук Registration Date 14-02-2020 Organization Vasyl' Stus Donetsk National University popup.description2 The reactions of hydrogen atom transfer and proton-coupled electron transport in the processes of aerobic oxidation of organic molecules have been investigated using the results of kinetic studies and quantum chemical calculations of the molecular and electronic characteristics of substrates and intermediates. A comparative study of N-hydroxyimides: 1-hydroxybenzotriazole, violuric acid and N-hydroxyphthalimide as a redox mediator by decolorization indigo carmine catalyzed by laccase from Trametes versicolor was performed. Oxidative degradation of the dye results from the coupling of two catalytic cycles. In the first catalytic cycle, the mediators are oxidized by laccase by the mechanism of proton-coupled electron transport to highly reactive radicals, which further oxidize the substrate in the non-enzymatic cycle via the proton transfer mechanism. The kinetics of the separation reactions of the hydrogen atom by phthalimide-N-oxyl radicals from the а-C-H bonds of benzyl alcohols were investigated. The reactivity of para-substituted benzyl alcohols is increasing in a number of: 4-NO2PhCH2OH, PhCH2OH, 4-Cl-PhCH2OH, 4-Ме-PhCH2OH, 4-МеО-PhCH2OH. It is shown that the rate constants of the H-atom separation reactions by N-oxyl radicals from the C-H bonds of n-substituted benzyl alcohols depend on the "sigma"+-substituent constants and the spin density distribution between the nitrogen and oxygen atoms in the >N-O radicals. Product Description popup.authors Andreev Oleksii V. Hordeeva Iryna O. Zosenko Olha O. Kushch Olha V. Levchenko Oleksii M. Lesishina Yuliya O. Serheeva Yuliia Yu. Starkova Hanna M. Tsiapalo Oleksandr S. popup.nrat_date 2020-04-02 Close