Studies in free radical initiation

1996 ◽  
Vol 111 (1) ◽  
pp. 265-280
Author(s):  
L. H. García-Rubio
Keyword(s):  
Free Radical ◽  
Radical Initiation ◽  
Free Radical Initiation

Relative Reactivities of 1,1,1-Trichloroethane and 1,1,1-Trichlorotrifluoroethane in Competitive Addition Reactions

1992 ◽  
Vol 57 (6) ◽  
pp. 1291-1298 ◽  
Author(s):  
František Adámek ◽  
Milan Hájek ◽  
Zbyněk Janoušek
Keyword(s):  
Free Radical ◽  
Reaction Mechanism ◽  
Relative Reactivity ◽  
Addition Reactions ◽  
Radical Initiation ◽  
Amine Complexes ◽  
Free Radical Initiation ◽  
Ru Complexes ◽  
Radical Initiators

Relative reactivity of CH3CCl3 and CF3CCl3 measured in competitive addition reactions with 1-hexene in the presence of free radical initiators or Cu, Pd and Ru complexes was found to depend on the type of catalyst. The unusual course of the reaction has been found in the additions catalyzed with copper(I)-amine complexes where CH3CCl3 in competition with CF3CCl3 was completely unreactive. The results have been explained in terms of the change of reaction mechanism and compared with classical free radical initiation.

Features of mechanism of free radical initiation in polymers under exposure to nitrogen oxides

2008 ◽  
Vol 19 (6) ◽  
pp. 475-484 ◽  
Author(s):  
E. Y. Davydov ◽  
I. S. Gaponova ◽  
T. V. Pokholok ◽  
A. P. Vorotnikov ◽  
G. B. Pariiskii ◽  
...  
Keyword(s):  
Free Radical ◽  
Nitrogen Oxides ◽  
Radical Initiation ◽  
Free Radical Initiation

Mechanistic insights into the reaction of CF3CCl3 with SO3: Theory and experiment

2012 ◽  
Vol 66 (11) ◽  
Author(s):  
Zhi-Zheng Liu ◽  
Zhi-Rong Chen ◽  
Hong Yin ◽  
Shen-Feng Yuan
Keyword(s):  
Free Radical ◽  
Density Functional ◽  
Radical Initiation ◽  
Radical Chain ◽  
The Density Functional Theory ◽  
Free Radical Initiation ◽  
Control Step ◽  
Mercury Salts ◽  
Initiation Stage

AbstractReaction mechanism of 1,1,1-trifluorotrichloroethane (CF3CCl3) and sulphur trioxide (SO3) in the presence of mercury salts (Hg2SO4 and HgSO4) was studied applying the density functional theory (DFT) at the UB3LYP/6-31+G(d,p) level. It was found that this reaction occurs in the free radical chain path as follows: mercury(I) sulphate free radical is generated by heat, causing CF3CCl3 to produce the CF3CCl2 free radical which reacts with SO3 leading to the formation of CF3CCl2OSO2 decomposing into CF3COCl and SO2Cl. The SO2Cl free radical triggers CF3CCl3 to regenerate CF3CCl2 which recycles the free radical growth reaction. This elementary reaction has the highest energy barrier and it is therefore the rate control step of the whole reaction path. Experiment data can confirm the existence of the mercury(I) salt free radical and the free radical initiation stage. So, mercury salts play the role of initiators not that of catalysts. The results agree well with our hypothesis.

Sign in / Sign up

Export Citation Format

Share Document