Recoil ³⁸CI Reactions with Halobenzenes: Substituent Effects

Abstract

Reactions of recoil 3 8 CI atoms with substituted halobenzenes have been investigated. The organic yields in all the investigated systems were enhanced when the samples were exposed to a relatively high accompanying gamma dose. The results suggest that the substituent F on the benzene ring has no effect on the reactions of recoil 3, C1 atoms. I 2 had no effect on the yields measured with o-and p-C 6 H 4 FCH,Cl compounds, suggesting the absence of thermal reactions. However, both the total organic and parent yields were considerably reduced in o-and p-C 6 H 4 C1CF 3 compounds when I 2 was added. The lower 38 C1-for-Cl substitution yield in o-C"H 4 C1CFJ than that in para isomer was attributed to steric effects. Relative reactivities of recoil CI in mixtures of some of the investigated compounds were evaluated using the model developed by KONTIS and URCH.