Addition and elimination kinetics in OH radical induced oxidation of phenol and cresols in acidic and alkaline solutions

Spectroelectrochemical studies of nuclease-active zinc(II) coordination compounds from the ligands Hpyramol and Hpyrimol

“…Similar absorption bands have previously been observed for phenoxyl radicals, and have been attributed to -* transitions [29][30][31][32][33]. It is well known that the formation of a phenoxyl radical is triggered by the attack of the phenoxyl ring by a hydroxyl • OH radical [35][36][37][38], which may take place through at least two different types of oxidation reactions with • OH. The first reaction pathway leads to an electronic transition around 320 nm, and is called the ipso attack.…”

“…Three new peaks are finally observed at 308, 387 and 326 nm. The comparison of the spectral data of this compound with those of the previous systems reveals that the electrochemical oxidation of Zn 2 (pyrimol) 2 Cl 2 yields the same benzoquinone methide-type product via the formation of a phenoxyl radical [34][35][36][37].…”

“…This signal at g = 2.098 most likely results from the formation of a phenoxyl radical [32][33][34][35][36][37]41] as depicted in Eqs. (2) and (3) (Scheme 2), which is corroborated by the spectral changes occurred during the third electron transfer, corresponding to the phenoxyl radical formation via the attack of a • OH radical.…”

Bisphenol A reactions with hydroxyl radicals: diverse pathways determined between deionized water and tertiary treated wastewater solutions

“…The typical clean water pathway for hydroxyl radical reaction with phenolic compounds involves addition of the radical to the aromatic ring to form a transient cyclohexadienyl species [31][32][33]. This transient has a lifetime on the microsecond timescale and is completely transformed to the stable hydroxylated product by 0.5 ms (Fig.…”

Role of reactive intermediates in the radiolytic degradation of Acid Red 1 in aqueous solution

“…In the reaction of two cyclohexadienyl-type radicals, as it was discussed formerly, either a dimer or a partly saturated molecule plus a new dye molecule with extra OH group forms. When the HO d radical addition takes place to the ring, which carries the hydroxyl group substituent, there is a possibility for water elimination forming phenoxyl-type radical (Roder et al, 1999). The phenoxyl-type radicals are not sensitive to oxygen.…”