Relative rate constants for the reaction of ground-state oxygen atoms with partly fluorinated propylenes and butenes
Abstract
The reactivity of ground-state oxygen atoms generated by mercury-sensitized decomposition of N2O has been investigated with olefins containing fluorine. Relative rate constants for the reaction with seven propylenes and butenes containing one to three fluorine atoms were measured by the competitive method at 23 ± 1 °C. The results are summarized below relative to a common reference olefin (ethylene): CH3CFCH2, 2.66 : CH2FCH
CH2, 1.12 : CH3CH
CF2, 2.4 : CF3CH
CH2, 0.057 : CH2FCH2CH
CH2, 3.30 : CF3(CH3)C
CH2, 0.45 : CH3CH2CF
CF2, 5.0. Replacement of hydrogen by fluorine at any position in the molecule decreased the reactivity of the olefin to O3P atoms. The variations in the relative rate constants are discussed in terms of the electron-withdrawing inductive effect and electron-donating mesomeric effect of the fluorine atom.