Oxidative addition leaving group reactivity order

Therefore, the mechanism must be concerted. However, in contrast to the concerted oxidative addition of H2, the addition of vinyl and phenyl C-X bonds occurs more rapidly with complexes than with d complexes. The reactions are still second order, and the normal order for leaving group reactivity is foimd. 

The hydroxyl proton in the intermediate 3 can migrate intramolecularly only with acylperoxo-type oxidants. Hence, acylperoxo-type oxidants are more effective than allq lperoxo oxidants. Additionally, it was observed that the presence of electron-withdrawing substituents on the peroxy acid increased the reaction rate because they made the conjugate base a better leaving group. Therefore, the reactivity of oxidants follows this order CF3CO3H > monopermaleic... 

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