Trifluoroacetoxy anion

This is an Sk2 displacement of a trifluoroacetoxy anion by a fluoride anion. The related Sk2 mechanism is not favored because of steric factors. Specifically, the trifluoroacetate resides at a tertiary center. Please note that the fluoride anion is... 

Aryl-A3-iodanes bearing an electron-deficient alkyl ligand such as aryl(sul-fonylmethyl)-A3-iodanes (Section 3.2.7) and aryl(perfluoroalkyl)-A3-iodanes are relatively stable. A series of (perfluoroalkyl)phenyl-A3-iodanes 96 were synthesized in good yields by treating bis(trifluoroacetoxy)-A3-iodanes with benzene in the presence of triflic acid [47]. The AModanes 96 transfer the perfluoroalkyl groups to a variety of nucleophiles with reductive elimination of iodobenzene. The nucleophiles involve Grignard reagents, alkyllithiums, enolate anions, alkenes, alkynes, trimethylsilyl enol ethers, arenes, phenols, and thiols. In these reactions, the AModane 96 serves as a source of the perfluoroalkyl cation and, in... 

Recyclable [bis(trifluoroacetoxy)iodo]arenes 66 and 70 are excellent reagents for oxidative coupling of thiophenes or pyrroles [79] and for direct oxidative cyanation of heteroaromatic compounds using Me3SiCN as source of cyanide anion [80,81]. 

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