Direct determination of kinetic coefficients

The co-oxidation or competitive oxidation of aldehydes, either among themselves or with hydrocarbons, provides interesting information on the reactivity of peracyl radicals [61]. 

In this project, co-oxidation with 1,4-cyclohexadiene was chosen since its oxidation products are easy to analyze, because they involve formation of benzene from the H02 radicals which propagate the chain, the overall stoichiometry being 

Therefore, it has been possible to determine the relative reactivities, rl (1 

The values of ri and r2 indicate that the reactivity of cyclohexadiene and aldehydes is approximately the same with regard to peracyl and hydroperoxy radicals. Nevertheless, in co-oxidation with cyclohexadiene or heptanal, benzaldehyde does not appear to be very reactive. This observation has also been made with the system butyraldehyde—benzaldehyde [47]. 

The results obtained for benzaldehyde—cyclohexene co-oxidation [51] appear to indicate that the reaction occurs with addition to the double bond, viz. 

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