Formation and reactivity of phenylperoxyl radicals in aqueous solutions

Journal Article · Thu Aug 18 04:00:00 EDT 1994 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100084a017· OSTI ID:7015208

Alfassi, Z B; Marguet, S; Neta, P ^[1]

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1. National Inst. of Standards and Technology, Gaithersburg, MD (United States)

The reaction of phenyl radicals with oxygen, to produce phenylperoxyl radicals, and the reactions of several phenylperoxyl radicals with a number of organic compounds in aqueous solutions have been studied by pulse radiolysis. Phenyl radicals were produced by reduction of aryl halides with hydrated electrons. The rate constant for the reaction of 4-carboxyphenyl with O[sub 2] was determined from the rate of buildup of the peroxyl radical absorption at 520 nm as a function of [O[sub 2]] and found to be 1.6 x 10[sup 9] L mol[sup [minus]1] s[sup [minus]1]. Phenyl radicals react with 2-PrOH by H abstraction; a rate constants of 4 x 10[sup 6] L mol[sup [minus]1] s[sup [minus]1] was determined for 4-carboxyphenyl by competition with the reaction of this radical with O[sub 2]. Phenylperoxyl radicals react with 4-methoxyphenolate ions, trolox C(6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), ascorbate ions, chlorpromazine, and ABTS [2,2[prime]-azinobis(3-ethylbenzothiazoline-6-sulfonate ion)] by one-electron oxidation. The rate constants for such reactions, determined from the rate of formation of the one-electron oxidation product as a function of substrate concentration, were found to be near 10[sup 8]-10[sup 9] L mol[sup [minus]1] s[sup [minus]1]. 24 refs., 4 figs., 1 tab.

• OSTI ID: 7015208
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 98:33; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400201 -- Chemical & Physicochemical Properties
400600* -- Radiation Chemistry
ALCOHOLS
AQUEOUS SOLUTIONS
AROMATICS
ARYL RADICALS
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DECOMPOSITION
DISPERSIONS
ELECTRONS
ELEMENTARY PARTICLES
ELEMENTS
FERMIONS
HYDROXY COMPOUNDS
KINETICS
LEPTONS
MIXTURES
NONMETALS
ORGANIC COMPOUNDS
OXIDATION
OXYGEN
PHENOLS
PHENYL RADICALS
PROPANOLS
RADIATION EFFECTS
RADICALS
RADIOLYSIS
REACTION KINETICS
SOLUTIONS
SOLVATED ELECTRONS