Electron transfer processes oxidative fluorination

The proposed mechanism of oxidative fluorination of unsaturated compounds by halogen fluorides [84-86] and VF5 [33] includes electron transfer from substrate to halogen fluoride or VF5 as a first step, followed by addition of F" to a radical-cation, leading to formation of a radical and its further oxidation to carbocation (see Eq. 12, pathways A,B). It should be pointed out that this is not the only direction, and the actual mechanism may depend strongly on the substrates and reaction conditions. Other mechanisms, such as a radical process (pathway C), cannot be ruled out. 

It is now reasonably well established that cobalt trifluoride fluorinations proceed via a one-electron transfer oxidative process [74, 75] as outlined in Figure 2.17. 

Fluorine is the more electronegative element, so in HF it has an oxidation number of-1 and hydrogen has an oxidation number of +1. This is a redox process where electrons are transferred from H2 to F2 to create HF. 

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