Hydroxyl radical induced oxidation of diethyl ether in oxygenated aqueous solution. A product and pulse radiolysis study. [Gamma radiation]
The reactions of peroxyl radicals derived from diethyl ether were investigated by product analyses and pulse-radiolytic techniques. The products and their G values (in brackets) in the ..gamma.. radiolysis of diethyl ether (10/sup -3/ M) in N/sub 2/O/O/sub 2/-saturated aqueous solutions at 0.43 W kg/sup -1/ are acetaldehyde (0.6), ethanol (0.6), ethyl acetate (2.8), ethyl formate (0.7), formaldehyde (0.4), hydrogen peroxide (2.1), 1-ethoxyethyl hydroperoxide (1.2), and 2-ethoxyacetaldehyde (approx. 0.5). Except for the latter, all products have the 1-ethoxyethylperoxy radical (I) as a precursor. It is formed as the major radical by OH abstraction of the ..cap alpha..-H atom (96%) followed by O/sub 2/ addition. Besides other bimolecular decay processes of I which are also discussed, there is an important route leading to 1-ethoxyethyloxyl radicals and O/sub 2/: 2I ..-->.. 2CH/sub 3/CH(O)OEt + O/sub 2/. The oxyl radical rearranges in aqueous solutions to the 1-ethoxy-1-hydroxyethyl radical: CH/sub 3/CH(O)OEt ..-->.. CH/sub 3/C(OH)OEt. The latter adds oxygen to give the corresponding peroxyl radical, which eliminates HO/sub 2/. in a fast spontaneous reaction to give ethyl acetate: CH/sub 3/C(OH)OEt + O/sub 2/ - HO/sub 2/. ..-->.. CH/sub 3/COOEt. Evidence for the formation of HO/sub 2/. (O/sub 2//sup -/. in neutral and basic solutions) according to the above reaction sequence was provided by pulse-spectrometric and pulse-conductometric measurements. 1-Ethoxyethyl hydroperoxide is thought to result from the reduction of I by O/sub 2//sup -/.. At much lower dose rates (0.0048 W kg/sup -1/) an intramolecular H abstraction competes with the bimolecular decay of I. This process leads to a different product distribution and to the formation of acidic products.
- Research Organization:
- Max-Planck-Institut fuer Strahlenchemie, Ruhr, Germany
- OSTI ID:
- 6846999
- Journal Information:
- J. Phys. Chem.; (United States), Vol. 86:11
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ACETALDEHYDE
G VALUE
ACETIC ACID ESTERS
CARBOXYLIC ACID ESTERS
ETHANOL
ETHYL ETHER
OXIDATION
RADIOLYSIS
FORMALDEHYDE
HYDROGEN PEROXIDE
PEROXIDES
AQUEOUS SOLUTIONS
CHEMICAL REACTION KINETICS
EXPERIMENTAL DATA
GAMMA RADIATION
HYDROXYL RADICALS
NITROUS OXIDE
OXYGEN
PEROXY RADICALS
PH VALUE
PULSED IRRADIATION
RADIATION DOSES
REACTION INTERMEDIATES
ALCOHOLS
ALDEHYDES
CHALCOGENIDES
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
DATA
DECOMPOSITION
DISPERSIONS
DOSES
ELECTROMAGNETIC RADIATION
ELEMENTS
ESTERS
ETHERS
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
INFORMATION
IONIZING RADIATIONS
IRRADIATION
KINETICS
MIXTURES
NITROGEN COMPOUNDS
NITROGEN OXIDES
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS
RADICALS
REACTION KINETICS
SOLUTIONS
400600* - Radiation Chemistry