Conformational equilibrium of the thermal unimolecular decomposition reactions of substituted 4-fluorophenyl 1,2,4-trioxanes

the unimolecular fragmentations of two fluorine substituted 1,2,4-trioxanes molecules had been interpreted considering the experimental activation parameters of the thermal decomposition reactions in solution. the kinetic data can be rationalized through the postulation of conformational equilibrium of each of the cis-6-(4-fluorophenyl)-5,6-[2-(4- fluorophenyl)-propyliden-3,3-tetramethylene-1,2,4-trioxacyclohexane (i) and cis-6-(4- fluorophenyl)-5,6-[2-(4-fluorophenyl)]-3-hydroxipropyliden-3,3-tetramethylene-1,2,4- trioxacyclohexane (ii) molecules, which would originate intermediate diradicals in their thermolysis in methanol and in n-hexane solutions. the kinetics data and spectroscopic (uv) studies already reported are in close agreement with an ab-initio dft level calculation performed on those molecules.