ChemInform Abstract: NUCLEOPHILIC SUBSTITUTION IN ORGANOMERCURY HALIDES BY A FREE-RADICAL CHAIN PROCESS (SRN1)

1979 ◽  
Vol 10 (22) ◽  
Author(s):  
G. A. RUSSELL ◽  
J. HERSHBERGER ◽  
K. OWENS
Keyword(s):  
Free Radical ◽  
Nucleophilic Substitution ◽  
Chain Process ◽  
Radical Chain ◽  
Radical Chain Process

The First Polycondensation through a Free Radical Chain Process

1997 ◽  
Vol 119 (37) ◽  
pp. 8718-8719 ◽  
Author(s):  
Takeshi Endo ◽  
Nobuo Torii ◽  
Toshikazu Takata ◽  
Tsutomu Yokozawa ◽  
Toshio Koizumi
Keyword(s):  
Free Radical ◽  
Chain Process ◽  
Radical Chain ◽  
Radical Chain Process

On the electron transfer and hydrogen atom abstraction mechanism for 1-benzyl-1,4-dihydronicotinamide reduction of benzoquinones

1990 ◽  
Vol 68 (10) ◽  
pp. 1662-1667 ◽  
Author(s):  
Dennis D. Tanner ◽  
Abdelmajid Kharrat ◽  
H. Oumar-Mahamat
Keyword(s):  
Electron Transfer ◽  
Free Radical ◽  
Hydrogen Atom ◽  
Hydrogen Atom Transfer ◽  
Chain Process ◽  
Single Electron Transfer ◽  
Second Order Reaction ◽  
Radical Chain ◽  
Radical Reduction ◽  
Radical Chain Process

The reduction of p-benzoquinone (BQ) by 1-benzyl-1,4-dihydronicotinamide (BNAH) proceeds by a free-radical chain mechanism initiated by single electron transfer (SET). In dry deoxygenated acetonitrile, the chain, whose propagation steps contain a SET–hydrogen atom transfer sequence, could be inhibited by dinitrobenzene and initiated by di-tert-butylperoxyoxalate. The reduction does not follow second-order reaction kinetics. The fractional order of each reactant was found to be 0.80 and 1.36 for BNAH and BQ, respectively. The AG0 values for both the initiation and the propagation steps were evaluated electro-chemically (CV) and were found to be of a reasonable magnitude to sustain a free-radical chain process. Keywords: 1-benzyl-1,4-dihydronicotinamide, p-benzoquinone, free radical, reduction.

Free Radical Bromination of Saturated Hydrocarbons using Bromine and Mercuric Oxide

1972 ◽  
Vol 50 (19) ◽  
pp. 3109-3116 ◽  
Author(s):  
N. J. Bunce
Keyword(s):  
Free Radical ◽  
Hydrogen Abstraction ◽  
Chain Process ◽  
Mercuric Oxide ◽  
Saturated Hydrocarbons ◽  
Radical Chain ◽  
Radical Bromination ◽  
Mercury Oxide ◽  
Alkyl Bromides ◽  
Radical Chain Process

The reaction of alkanes with a mixture of bromine and mercuric oxide gives alkyl bromides in preparatively useful yields. The reagent is significantly more reactive than elemental bromine, and it is believed that bromine monoxide, formed insitu by the interaction of bromine and mercury oxide, is the reactive intermediate. Bromination by bromine monoxide is a free radical chain process in which hydrogen abstraction is carried out predominantly by bromoxy (BrO•) radicals, and to a lesser extent by bromine atoms.

Reactivity of substituted styrenes in the catalytic addition reaction with the trichloromethyl radical

1990 ◽  
Vol 55 (12) ◽  
pp. 2949-2955 ◽  
Author(s):  
Milan Hájek ◽  
Přemysl Šilhavý ◽  
Božena Špirková
Keyword(s):  
Free Radical ◽  
Double Bond ◽  
Benzene Ring ◽  
Addition Reaction ◽  
Chain Process ◽  
Hammett Equation ◽  
Radical Chain ◽  
Catalytic Addition ◽  
Radical Chain Process ◽  
Trichloromethyl Radical

Relative reactivities have been investigated in the catalytic addition of tetrachloromethane to substituted styrenes by the competitive method. The polar effects of substituents on benzene ring were correlated with Hammett equation for a copper and ruthenium catalyst, giving ρ values equal to -0.39 and -0.18 respectively. The results indicate that in contrast to classical additions the catalytic addition of tetrachloromethane is not a free radical chain process but that the trichloromethyl radical, presumably coordinated, reacts with the carbon-carbon double bond via innersphere pathways.

Sign in / Sign up

Export Citation Format

Share Document