Mechanism of toluene oxidation with CrO3

What is the mechanism for the following oxidation of toluene with $\ce{CrO3}$ in acetic anhydride?



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> Use of chromic oxide ($\ce{CrO3}$): Toluene or substituted toluene is converted to benzylidene diacetate on treating with chromic oxide in acetic anhydride. The benzylidene diacetate can be hydrloyzed to corresponding benzaldehyde with aqueuous acid.
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[![enter image description here](https://i.stack.imgur.com/HizIn.png)](https://i.stack.imgur.com/HizIn.png)




The following mechanism is based on the findings made in *The Mechanism of the Etard Reaction[[1]](https://doi.org/10.1016/s0040-4020(01)98572-2)*.




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[![Etard like reaction](https://i.stack.imgur.com/K4tnI.jpg)](https://i.stack.imgur.com/K4tnI.jpg)




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**Reference:**


[(1)](https://doi.org/10.1016/s0040-4020(01)98572-2) Necsoiu, I.; Balaban, A. T.; Pascaru, I.; Sliam, E.; Elian, M.; Nenitzescu, C. D. The Mechanism of the Etard Reaction. *Tetrahedron* **1963**, *19* (7), 1133–1142.


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