Trimethylsilyl fluorosulfonyldifluoroacetate TFDA

As mentioned in the Introduction, imidazole is found in biologic systems and, as mentioned, is quite robust chemically. For example, the imidazole ring system is not readily oxidized Y-oxidation does not readily occur. Very powerful oxidizing agents are required to oxidize the imidazole ring. Chemically, this was recently reported by the use of trimethylsilyl fluorosulfonyldifluoroacetate (TFDA). Mechanistically, this proceeds similar to the acyl transfer reaction described earlier. 

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