Catalytic oxidations using cobalt(II) complexes - Advances in Catalytic Activation of Dioxygen by Metal Complexes - page 287

4.4 Oxidative cleavage of a stilbene derivative

In the presence of the cobaloxime(II) catalyst at

room temperature and 1 atm or air,
undergoes oxidative dehydrogenation to the
corresponding stilbenequinone (StQ), and parallel oxidative cleavage at the
C=C double bond to afford 2,6-di- tert -butyl-4-hydroxybenzaldehyde (Ald,
Figure 28) 69 . The relative contribution of these two stoichiometries depends
on the degree of conversion.

In the steady state the relative rate of formation of StQ and Ald is
approximately constant throughout a given run, indicating that they are
formed in competitive reactions, via a common free-radical intermediate
(Figure 29) detected by EPR spectroscopy during the reaction.