Electrogeneration of Triphenyltin Radical, Anion, and Cation. Electrochemical Initiation of Tin Hydride-Promoted Radical Chain Reactions

1996 ◽  
Vol 61 (26) ◽  
pp. 9402-9408 ◽  
Author(s):  
Hideo Tanaka ◽  
Hidenori Ogawa ◽  
Hiroaki Suga ◽  
Sigeru Torii ◽  
Anny Jutand ◽  
...  
Keyword(s):  
Radical Anion ◽  
Radical Chain ◽  
Chain Reactions

scholarly journals Protein hydroperoxides can give rise to reactive free radicals

1995 ◽  
Vol 305 (2) ◽  
pp. 643-649 ◽  
Author(s):  
M J Davies ◽  
S Fu ◽  
R T Dean
Keyword(s):  
Free Radicals ◽  
Amino Acid ◽  
Radical Anion ◽  
Similar Process ◽  
Side Chain ◽  
Radical Species ◽  
Radical Chain ◽  
Chain Reactions ◽  
Oxygen Yield ◽  
Rearrangement Processes

Proteins damaged by free-radical-generating systems in the presence of oxygen yield relatively long-lived protein hydroperoxides. These hydroperoxides have been shown by e.p.r. spectroscopy to be readily degraded to reactive free radicals on reaction with iron(II) complexes. Comparison of the observed spectra with those obtained with free amino acid hydroperoxides had allowed identification of some of the protein-derived radical species (including a number of carbon-centred radicals, alkoxyl radicals and a species believed to be the CO2 radical anion) and the elucidation of novel fragmentation and rearrangement processes involving amino acid side chains. In particular, degradation of hydroperoxide functions on the side chain of glutamic acid is shown to result in decarboxylation at the side-chain carboxy group via the formation of the CO2 radical anion; the generation of an identical radical from hydroperoxide groups on proteins suggests that a similar process occurs with these molecules. In a number of cases these fragmentation and rearrangement reactions give rise to further reactive free radicals (R., O2-./HO2., CO2-.) which may act as chain-carrying species in protein oxidations. These studies suggest that protein hydroperoxides are capable of initiating further radical chain reactions both intra- and inter-molecularly, and provide information on some of the fundamental mechanisms of protein alteration and side-chain fragmentation.

Radical Chain Reduction via Carbon Dioxide Radical Anion (CO2•–)

2021 ◽  
Author(s):  
Cecilia M. Hendy ◽  
Gavin C. Smith ◽  
Zihao Xu ◽  
Tianquan Lian ◽  
Nathan T. Jui
Keyword(s):  
Carbon Dioxide ◽  
Radical Anion ◽  
Radical Chain

ChemInform Abstract: Concise Syntheses of L-Selenomethionine and of L-Selenocystine Using Radical Chain Reactions.

ChemInform ◽  
1987 ◽  
Vol 18 (4) ◽  
Author(s):  
D. H. R. BARTON ◽  
D. BRIDON ◽  
Y. HERVE ◽  
P. POTIER ◽  
J. THIERRY ◽  
...  
Keyword(s):  
Radical Chain ◽  
Chain Reactions

scholarly journals The detection and inhibition of free radical chain reactions

1942 ◽  
Vol 180 (982) ◽  
pp. 237-256 ◽  
Keyword(s):  
Nitric Oxide ◽  
Free Radical ◽  
Chemical Analysis ◽  
Diethyl Ether ◽  
Pressure Increase ◽  
Stationary States ◽  
Decomposition Rates ◽  
Radical Chain ◽  
Chain Reactions ◽  
Limiting Values

Part I. Comparison of nitric oxide and propylene as inhibitors The reduction by propylene of the rate of pressure increase in the decomposition of propaldehyde at 550° has been shown by chemical analysis to represent a true inhibition of the reaction, and not to be due n an important degree to an induced polymerization of the propylene. With propaldehyde and with diethyl ether the limiting values to which the decomposition rates are reduced by nitric oxide and by propylene respectively are the same, although much more propylene is required to produce a given degree of inhibition. From this it is concluded that the limiting rates are more probably those of independent non-chain processes, than those characteristic of stationary states where the inhibitor starts and stops chains with equal efficiency.

Dithiocarbonate group transfer in radical chain reactions

1990 ◽  
Vol 31 (18) ◽  
pp. 2565-2568 ◽  
Author(s):  
Judith E. Forbes ◽  
Catherine Tailhan ◽  
Samir Z. Zard
Keyword(s):  
Radical Chain ◽  
Group Transfer ◽  
Chain Reactions

Resonance-stabilized hydrocarbon-radical chain reactions may explain soot inception and growth

Science ◽  
2018 ◽  
Vol 361 (6406) ◽  
pp. 997-1000 ◽  
Author(s):  
K. O. Johansson ◽  
M. P. Head-Gordon ◽  
P. E. Schrader ◽  
K. R. Wilson ◽  
H. A. Michelsen
Keyword(s):  
Interstellar Dust ◽  
Hydrogen Abstraction ◽  
Particle Formation ◽  
Reaction Pathways ◽  
Radical Chain ◽  
Carbonaceous Particle ◽  
Carbonaceous Particles ◽  
Chain Reactions ◽  
Polycyclic Aromatic ◽  
Covalently Bound

Mystery surrounds the transition from gas-phase hydrocarbon precursors to terrestrial soot and interstellar dust, which are carbonaceous particles formed under similar conditions. Although polycyclic aromatic hydrocarbons (PAHs) are known precursors to high-temperature carbonaceous-particle formation, the molecular pathways that initiate particle formation are unknown. We present experimental and theoretical evidence for rapid molecular clustering–reaction pathways involving radicals with extended conjugation. These radicals react with other hydrocarbon species to form covalently bound complexes that promote further growth and clustering by regenerating resonance-stabilized radicals through low-barrier hydrogen-abstraction and hydrogen-ejection reactions. Such radical–chain reaction pathways may lead to covalently bound clusters of PAHs and other hydrocarbons that would otherwise be too small to condense at high temperatures, thus providing the key mechanistic steps for rapid particle formation and surface growth by hydrocarbon chemisorption.

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