Radiation-induced Rearrangement of Ethylene Glycol in Aqueous Solution

1971 ◽  
Vol 49 (14) ◽  
pp. 2382-2389 ◽  
Author(s):  
C. E. Burchill ◽  
K. M. Perron
Keyword(s):  
Hydrogen Peroxide ◽  
Ethylene Glycol ◽  
Aqueous Solutions ◽  
Transfer Reaction ◽  
Major Product ◽  
Hydrogen Atom Transfer ◽  
Γ Irradiation ◽  
Radical Chain ◽  
Radiation Induced ◽  
A Chain

Under γ-irradiation, aqueous solutions of ethylene glycol containing hydrogen peroxide form acetaldehyde as a major product via a free-radical chain rearrangement. The yield of acetaldehyde is essentially unchanged when hydrogen peroxide is replaced by N2O or HClO4. A mechanism is proposed in which the glycol radical, ĊOHCH2OH, rearranges to the acetaldehyde precursor, ĊH2CHO, followed by the hydrogen atom transfer reaction;[Formula: see text]thus propagating a chain reaction.2The rearrangement is also induced by the photo-dissociation of H2O2 in aqueous solutions of ethylene glycol.

Studies of radiation-induced reactions of ethylene in aqueous solution II. Reactions in the presence of oxygen as studied by pulse radiolysis and γ -irradiation techniques

1967 ◽  
Vol 300 (1463) ◽  
pp. 443-454 ◽  
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Peroxide ◽  
Rate Constants ◽  
Pulse Radiolysis ◽  
Major Product ◽  
Peroxy Radicals ◽  
Ferrous Ions ◽  
Constant Composition ◽  
Γ Irradiation ◽  
Radiation Induced

The radiolysis of dilute aqueous solutions containing ethylene and oxygen has been investigated. Pulse radiolysis was used to measure the rate constants for the addition of hydroxyl radicals to ethylene, the binary decomposition of the resulting hydroxyethyl radicals and their addition to ethylene and reaction with oxygen to yield peroxy radicals. The rate constants have also been determined for the mutual interaction of the peroxy radicals and their reaction with ferrous ions. The principal products of γ -irradiation were aldehydes and organic hydroperoxides. Hydrogen peroxide was found in yields close to the molecular yield from water. The polymer produced in the absence of oxygen was not formed, and glycollaldehyde, reported as a major product by previous workers, could not be detected. At constant composition of the gas mixtures, product yields were unaffected by total pressure in the range up to 40 atm, but were strongly dependent on the proportion of oxygen. Aldehyde yields were markedly greater at pH 1.2 than in neutral solution. The influence of ferrous ions an d of added hydrogen peroxide has been determined. The pulse radiolysis and γ -irradiation experiments complement one another and show that the radiation-induced oxidation of ethylene in aqueous solution involves the same primary reactions as occur in the absence of oxygen, followed by the formation and further reactions of peroxy radicals.

Radiation-induced oxidation of 2-propanol by hydrogen peroxide in aqueous solutions

1970 ◽  
Vol 48 (8) ◽  
pp. 1232-1238 ◽  
Author(s):  
C. E. Burchill ◽  
I. S. Ginns
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Peroxide ◽  
Aqueous Solutions ◽  
Lower Limit ◽  
Alcohol Concentration ◽  
Chain Mechanism ◽  
Radiation Induced ◽  
A Chain ◽  
High Yields ◽  
Radical Conversion

The radiation-induced oxidation of 2-propanol by hydrogen peroxide in neutral deaerated aqueous solution has been investigated. 2-Propanol is oxidized to acetone, and hydrogen peroxide reduced in stoichiometrically equivalent high yields. The yields are independent of hydrogen peroxide concentration in the range 5 × 10−2 to 10−3 M and linearly dependent on alcohol concentration in the range 0.13 to 1.05 M. The reaction yields increased with decreasing dose rate.The results are explained by a chain mechanism in which initiation occurs via H-atom abstraction from 2-propanol to form either (CH3)2ĊOH (1) or CH3 CHOH ĊH2 (2). 1 reacts with H2O2 in a chain propagating reaction[Formula: see text]2 may abstract the α hydrogen from the parent alcohol[Formula: see text]or undergo bimolecular termination. A lower limit of 53 ± 101mole−1 s−1 is estimated for the rate constant for this radical conversion reaction.

Free-Radical Reductions of Arenediazonium Ions in Aqueous Solution. VI. On Iododediazoniation

1985 ◽  
Vol 38 (6) ◽  
pp. 991 ◽  
Author(s):  
JE Packer ◽  
RER Taylor
Keyword(s):  
Aqueous Solution ◽  
Free Radical ◽  
Aqueous Solutions ◽  
Major Product ◽  
Chain Reaction ◽  
Γ Irradiation ◽  
A Chain

γ-Irradiation of aqueous solutions of p-ClC6H4N2+BF4- and KI initiates a chain reaction in which dichloroazobenzene is the major product. When iodine is also present the chain reaction is longer and the major product is chloroiodobenzene . The reaction � ������������������������� I2-·+ArN2+ → I2+Ar·+N2 is suggested to be propagation step in both reactions, with Ar · reacting with I3- in the presence of iodine and with ArN2+ in its absence. The relevance of these reactions to iododediazoniation is discussed.

Sulfamides Direct Radical-Mediated Chlorination of Aliphatic C–H Bonds

2019 ◽  
Author(s):  
Melanie Short ◽  
Mina Shehata ◽  
Matthew Sanders ◽  
Jennifer Roizen
Keyword(s):  
Hydrogen Atom ◽  
Transfer Reaction ◽  
Hydrogen Atom Transfer ◽  
Chain Propagation ◽  
Propagation Mechanism ◽  
Atom Transfer ◽  
Radical Chain ◽  
Radical Intermediates ◽  
Transfer Processes ◽  
Unusual Position

Sulfamides guide intermolecular chlorine transfer to gamma-C(sp<sup>3</sup>) centers. This unusual position-selectivity arises because accessed sulfamidyl radical intermediates engage in otherwise rare 1,6-hydrogen-atom transfer processes. The disclosed chlorine-transfer reaction relies on a light-initiated radical chain-propagation mechanism to oxidize C(sp<sup>3</sup>)-H bonds.

Sulfamides Direct Radical-Mediated Chlorination of Aliphatic C–H Bonds

2019 ◽  
Author(s):  
Melanie Short ◽  
Mina Shehata ◽  
Matthew Sanders ◽  
Jennifer Roizen
Keyword(s):  
Hydrogen Atom ◽  
Transfer Reaction ◽  
Hydrogen Atom Transfer ◽  
Chain Propagation ◽  
Propagation Mechanism ◽  
Atom Transfer ◽  
Radical Chain ◽  
Radical Intermediates ◽  
Transfer Processes ◽  
Unusual Position

Sulfamides guide intermolecular chlorine transfer to gamma-C(sp<sup>3</sup>) centers. This unusual position-selectivity arises because accessed sulfamidyl radical intermediates engage in otherwise rare 1,6-hydrogen-atom transfer processes. The disclosed chlorine-transfer reaction relies on a light-initiated radical chain-propagation mechanism to oxidize C(sp<sup>3</sup>)-H bonds.

Radiation-induced oxidation of 2-propanol by hydrogen peroxide in aqueous solutions

1970 ◽  
Vol 48 (18) ◽  
pp. 2948-2948
Author(s):  
C. E. Burchill ◽  
I. S. Ginns
Keyword(s):  
Hydrogen Peroxide ◽  
Aqueous Solutions ◽  
Radiation Induced

not available

γ-RADIATION-INDUCED HYDROGEN EXCHANGE REACTION IN LIQUID CYCLOHEXANE – HYDROGEN CHLORIDE SOLUTIONS

1966 ◽  
Vol 44 (22) ◽  
pp. 2645-2649 ◽  
Author(s):  
J. W. Fletcher ◽  
G. R. Freeman
Keyword(s):  
Exchange Reaction ◽  
Hydrogen Chloride ◽  
Hydrogen Exchange ◽  
Spectroscopic Method ◽  
Exchange Reactions ◽  
Radical Chain ◽  
Chloride System ◽  
Γ Radiation ◽  
Radiation Induced ◽  
A Chain

The overall exchange reactions[Formula: see text]have been initiated by radiolysis and measured by a nuclear magnetic resonance spectroscopic method. The reactions occur by a chain mechanism, with a chain length of ~ 104 in a 1 M solution of hydrogen chloride in cyclohexane. The mechanism is complex.The exchange reaction can also be initiated by the photolysis of chlorine or of hydrogen chloride.A chain exchange reaction does not occur between c-C6H12 and DI, D2S, or ND3. These results are consistent with the suggestion that the exchange reaction in the cyclohexane – hydrogen chloride system occurs by a free radical chain mechanism.This type of exchange reaction can cause difficulties in isotopic tracer studies.

Sulfamides Direct Radical-Mediated Chlorination of Aliphatic C–H Bonds

2019 ◽  
Author(s):  
Melanie Short ◽  
Mina Shehata ◽  
Matthew Sanders ◽  
Jennifer Roizen
Keyword(s):  
Hydrogen Atom ◽  
Transfer Reaction ◽  
Hydrogen Atom Transfer ◽  
Chain Propagation ◽  
Propagation Mechanism ◽  
Atom Transfer ◽  
Radical Chain ◽  
Radical Intermediates ◽  
Transfer Processes ◽  
Unusual Position

Sulfamides guide intermolecular chlorine transfer to gamma-C(sp<sup>3</sup>) centers. This unusual position-selectivity arises because accessed sulfamidyl radical intermediates engage in otherwise rare 1,6-hydrogen-atom transfer processes. The disclosed chlorine-transfer reaction relies on a light-initiated radical chain-propagation mechanism to oxidize C(sp<sup>3</sup>)-H bonds.

Sulfamides Direct Radical-Mediated Chlorination of Aliphatic C–H Bonds

2019 ◽  
Author(s):  
Melanie Short ◽  
Mina Shehata ◽  
Matthew Sanders ◽  
Jennifer Roizen
Keyword(s):  
Hydrogen Atom ◽  
Transfer Reaction ◽  
Hydrogen Atom Transfer ◽  
Chain Propagation ◽  
Propagation Mechanism ◽  
Atom Transfer ◽  
Radical Chain ◽  
Radical Intermediates ◽  
Transfer Processes ◽  
Unusual Position

Sulfamides guide intermolecular chlorine transfer to gamma-C(sp<sup>3</sup>) centers. This unusual position-selectivity arises because accessed sulfamidyl radical intermediates engage in otherwise rare 1,6-hydrogen-atom transfer processes. The disclosed chlorine-transfer reaction relies on a light-initiated radical chain-propagation mechanism to oxidize C(sp<sup>3</sup>)-H bonds.

Sign in / Sign up

Export Citation Format

Share Document