Reaction of Hydrogen Atom with Benzene: Kinetics and Mechanism

Article abstract of DOI:10.1021/j150656a021

The rate coefficients for the reactions H + C6H6 -> products (k₁) (1), H + C6D6 -> products (k₂) (2), D + C6H6 -> products (k₃) (3), and D + C6D6 -> products (k₄) (4) have been measured in the temperature range of 298-1000 K by using the pulsed photolysis-resonance fluorescence technique.On the basis of the obtained kinetic information, it is shown that the primary path in all these reactions is addition of the atom to the benzene ring form cyclohexadienyl radical.The rate coefficient for the thermal decomposition of the cyclohexadienyl radical has also been measured.When the rate coefficients for the formation and decomposition of the cyclohexadienyl radical are used, the standard heat of formation of cyclohexadienyl radical at 298 K is calculated to be 45.7 kcal/mol.The measured values of k₁-k₄ are compared with the results of previous investigations.Most of the observed kinetic behavior in these reactions has been explained on the basis of the addition-decomposition reaction scheme.