Inert Carbon Free Radicals. 11. Synthesis and Magnetic Behavior of (4,4'-Dicarboxytridecachlorotriphenyl)methyl Radical and Related Results

1994 ◽  
Vol 59 (9) ◽  
pp. 2604-2607 ◽  
Author(s):  
V. M. Domingo ◽  
J. Castaner ◽  
J. Riera ◽  
A. Labarta
Keyword(s):  
Free Radicals ◽  
Magnetic Behavior ◽  
Methyl Radical

Reactions of free radicals with aromatic compounds in the gaseous phase. II. Kinetics of the reaction of methyl radicals with phenol

1965 ◽  
Vol 18 (1) ◽  
pp. 20 ◽  
Author(s):  
MFR Mulcahy ◽  
DJ Williams
Keyword(s):  
Free Radicals ◽  
Gaseous Phase ◽  
Hydrogen Abstraction ◽  
High Reactivity ◽  
Phenoxy Radical ◽  
Methyl Radicals ◽  
Methyl Radical ◽  
Kinetics Of Formation ◽  
Phenolic Substances ◽  
Kinetics Of

Knowledge of the reactivity of phenols towards simple free radicals is needed to throw light on the behaviour of the phenolic substances involved in the pyrolysis of coal and other organic materials. In the present investigation the reaction between methyl radicals and phenol vapour has been studied a t total pressures from 0.5 to 3 cmHg and temperatures from 445 to 547°K, the concentrations of methyl radicals and phenol being varied from 2 × 10-12 to 4 × 10-11 and 1 × 10-8 to 8 × 10-7 mole cm-3 respectively. The main products identified by gas chromatography were methane and o- and p-cresol, together with a little anisole and 2,4- and 2,6-dimethylphenol. The cresols are produced via hydrogen abstraction Diagram followed by combination of a methyl radical at a ring position of the phenoxy radical either ortho or para to the oxygen atom, e.g. in the case of the para position: Diagram The kinetics can be explained by postulating (a) that the keto forms of the cresols (methylcyclohexadienones) formed initially by reaction (6) have a finite lifetime in the gaseous phase and (b) that these molecules, which contain a tertiary hydrogen atom α to a system of a carbonyl bond and two carbon-carbon double bonds, partly undergo hydrogen abstraction by methyl radicals before they are able to enolize: CH3· + (HCH3 = C6H4 = O → CH4 + CH3C6H4O· The mechanism is consistent with the kinetics of formation of methane, the distribu- tion of the free electron in the phenoxy radical, the formation of o- and p-cresols as major products, the kinetics of formation of the cresols, and the high reactivity of the intermediate product towards methyl radicals.

ChemInform Abstract: Two Functionalized Free Radicals of the Tris(2,4,6-trichlorophenyl) methyl Radical Series. Synthesis, Stability and EPR Analysis

ChemInform ◽  
2010 ◽  
Vol 26 (4) ◽  
pp. no-no
Author(s):  
J. CARILLA ◽  
L. FAJARI ◽  
L. JULIA ◽  
J. RIERA ◽  
L. VIADEL
Keyword(s):  
Free Radicals ◽  
Methyl Radical

ChemInform Abstract: THE MAGNETIC PROPERTIES OF VERDAZYL FREE RADICALS PART 3, THE ANOMALOUS MAGNETIC BEHAVIOR OF SYMMETRICAL TRIPHENYLVERDAZYL

1973 ◽  
Vol 4 (50) ◽  
pp. no-no
Author(s):  
NAGAO AZUMA ◽  
JUN YAMAUCHI ◽  
KAZUO MUKAI ◽  
HIROAKI OHYA-NISHIGUCHI ◽  
YASUO DEGUCHI
Keyword(s):  
Magnetic Properties ◽  
Free Radicals ◽  
Magnetic Behavior

Two functionalized free radicals of the tris(2,4,6-trichlorophenyl)methyl radical series. Synthesis, stability and EPR analysis

1994 ◽  
Vol 35 (35) ◽  
pp. 6529-6532 ◽  
Author(s):  
Josep Carilla ◽  
Lluís Fajarí ◽  
Luis Juliá ◽  
Juan Riera ◽  
Lluís Viadel
Keyword(s):  
Free Radicals ◽  
Methyl Radical

Magnetic Behavior of Organic Free Radicals with Localized and Delocalized Electrons

1989 ◽  
Vol 58 (9) ◽  
pp. 3361-3370 ◽  
Author(s):  
Kazuyoshi Takeda ◽  
Hiroyuki Deguchi ◽  
Takahiro Hoshiko ◽  
Kensuke Konishi ◽  
Keita Takahashi ◽  
...  
Keyword(s):  
Free Radicals ◽  
Magnetic Behavior

Free radicals in the reaction between t-butyl hydroperoxide and titanous ion: Some observations by electron spin resonance spectrometry

1965 ◽  
Vol 18 (8) ◽  
pp. 1177 ◽  
Author(s):  
MFR Mulcahy ◽  
JR Steven ◽  
JC Ward
Keyword(s):  
Aqueous Solution ◽  
Free Radicals ◽  
Electron Spin Resonance ◽  
Electron Spin ◽  
Peroxy Radicals ◽  
Methyl Radicals ◽  
Methyl Radical ◽  
Butyl Hydroperoxide ◽  
Spin Resonance ◽  
G Value

The reaction between t-butyl hydroperoxide and titanous ion in aqueous solution produces free methyl radicals detectable by electron spin resonance spectrometry (Dixon and Norman). However, the presence of titanous ion in concentrations greater than 0.01M broadens the spectrum of the methyl radical, causing it effectively to disappear at titanous concentrations greater than 0.1M. At hydroperoxide concentrations above 0.25M t-butyl peroxy radicals (identified by a strong single-line spectrum with g-value 2.0136) are produced by the reaction ���������� R. + (CH3)3COOH → RH + (CH3)3COO. Their concentration reaches a maximum about 1 sec after the concentration of the methyl radicals has fallen to an undetectable value and their half-life (≈ 5 sec) is about ten times that of the methyl radicals.

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