C-C BOND HOMOLYSIS IN (CF3S)3C-C(SCF3)3 AT ROOM-TEMPERATURE - THERMODYNAMIC, KINETIC, AND ELECTRON-SPIN RESONANCE RESULTS

In benzene solution at 10-60°C (CF3S)3C-C(SCF3)3 undergoes a reversible homolytic C-C cleavage reaction to yield (CF3S)3C radicals which were identified by ESR. From the dependence of the stationary concentration of (CF3S)3C on temperature the C-C bond dissociation energy is determined to be 13.7 kcal/mol. At 30°C the equilibrium constant for C-C homolysis is 7.5 X 10-10 M. The change in free entropy occurring on C-C homolysis corresponds to 3.6 eu. The activation energy and entropy for C-C bond cleavage are 21.0 kcal/mol and 7.5 eu, respectively. The experimental results concerning the facile C-C homolysis are interpreted essentially in terms of sterically induced destabilization of the C-C bond in (CF3S)3C-C(SCF3)3. © 1979, American Chemical Society. All rights reserved.