Oxidation of copper(II) bis(glycinate) by methyl free radicals in aqueous solutions. A pulse-radiolysis study. [Pulsed electrons]

Journal Article · Tue Dec 11 23:00:00 EST 1990 · Inorganic Chemistry; (USA)

DOI:https://doi.org/10.1021/ic00350a006· OSTI ID:5589429

Masarwa, M; Cohen, H; Glaser, R; Meyerstein, D ^[1]

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1. Ben-Gurion Univ. of the Negev, Beer-Sheva (Israel)

The reaction of {sm bullet}CH{sub 3} free radicals with Cu{sup II}(NH{sub 2}CH{sub 2}CO{sub 2}{sup {minus}}){sub 2} in aqueous solutions was studied. The formation of the unstable intermediate (NH{sub 2}CH{sub 2}CO{sub 2}{sup {minus}}){sub 2}Cu{sup III}-CH{sub 3}(aq) in this reaction was observed. This intermediate decomposes into Cu{sup III}(NH{sub 2}CH{sub 2}CO{sub 2}{sup {minus}}){sub 2}{sup +}(aq) + CH{sub 4}. The formation of Cu{sup III}(NH{sub 2}CH{sub 2}CO{sub 2}{sup {minus}}){sub 2}{sup +}(aq) is not observed, as this complex is short-lived under these conditions and decomposes via ligand oxidation. The {sm bullet}CH{sub 3} free radicals react with the transient complex (NH{sub 2}CH{sub 2}CO{sub 2}{sup {minus}}){sub 2}Cu{sup III}-CH{sub 3}(aq) to form ethane and Cu{sup II}(NH{sub 2}CH{sub 2}CO{sub 2}{sup {minus}}){sub 2}; the specific rate of this reaction approaches the diffusion-controlled limit. The results thus point out that aliphatic free radicals can oxidize copper(II) complexes to copper(III) complexes. The results suggest that the reactions of aliphatic free radicals with copper complexes might cause the reported radiosensitization by copper compounds. 18 refs., 3 figs., 3 tabs.

• OSTI ID: 5589429
• Journal Information: Inorganic Chemistry; (USA), Journal Name: Inorganic Chemistry; (USA) Vol. 29:25; ISSN 0020-1669; ISSN INOCA
• 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
ALKYL RADICALS
AMINO ACIDS
AQUEOUS SOLUTIONS
CARBOXYLIC ACIDS
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
COMPLEXES
COPPER COMPLEXES
DATA
DECOMPOSITION
DISPERSIONS
ELECTRONS
ELEMENTARY PARTICLES
EXPERIMENTAL DATA
FERMIONS
GLYCINE
INFORMATION
IRRADIATION
LEPTONS
METHYL RADICALS
MIXTURES
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
PULSED IRRADIATION
RADIATION CHEMISTRY
RADIATION EFFECTS
RADICALS
RADIOLYSIS
REDOX REACTIONS
SOLUTIONS
TRANSITION ELEMENT COMPLEXES