Abnormal Solvent Effects on Hydrogen Atom Abstraction. 3. Novel Kinetics in Sequential Proton Loss Electron Transfer Chemistry

Abstract

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Antioxidant Properties of Camelina sativa Oil and Press-Cakes

“…Most likely this was due to different reactivity of phenolate ion with free radicals. It is considered that the reaction between an antioxidant and a free radical proceeds according to the SPLET (sequential proton loss and electron transfer) mechanism; thus, formation of phenolate ion is crucial for antioxidant activity (Litwinienko and Ingold, 2005). Phenolate ions react better with free radicals, which are formed from parent molecules with low pK a : pK a of the DPPH parent molecule is around 8.5, while pK a of alcohol is 15-19 (Litwinienko and Ingold, 2003).…”

DFT/B3LYP Study to Investigate the Possible Ways for the Synthesize of Antioxidants with High Efficiency Based on Vitamin E

“…[12][13][14][15] This was named sequential proton loss electron transfer (SPLET), taking place in two steps (Eqs. 3.1 and 3.2)…”

DFT/B3LYP Study of the Substituent Effects on the Reaction Enthalpies of the Antioxidant Mechanisms of Magnolol Derivatives in the Gas-Phase and Water

“…This work also shows linear dependence between calculated enthalpies and the energy of the highest occupied molecular orbital (E HOMO ) of studied molecules in the two environments. Because SET-PT and SPLET mechanisms are of importance in solvated media, [18][19][20][21]33,41,70 it is interesting to explore how the solvent alters the reaction enthalpies of individual steps of the two mechanisms. Because Magnolol is a powerful water-soluble antioxidant, water as the main cell environment was chosen in order to assess the substituent effect on above mentioned enthalpies in solution-phase.…”