ISSN:
0538-8066
Keywords:
Chemistry
;
Physical Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The kinetics and mechanism of the free-radical chain dechlorination of C2Cl6, C2Cl5H, and sym-C2Cl4H2 in Et3SiH wereinvestigated over a wide temperature range. The propagation step of the dechlorination of chloroethanes (C2Clx H6-x) proceeds by the following reactions: Analysis of the temperature dependence of product formation gave the Arrhenius expressions for k4/k3 which in turn were utilized for the estimation of the absolute Arrhenius parameters for hydrogen abstraction from Et3SiH. Our results show that the values of Eabs are lower in Et3SiH than in c-C6H12 by about 2-3 kcal/mol, while the A factors are almost equal. In competitive studies k2 was determined versus Br abstraction from n-C5H11Br. The relative Arrhenius parameters determined by this method show that variations in both A factors and activationenergies are responsible for the reactivity trends observed in the Cl transfer reactions of Et3Si radicals.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/kin.550130104
