Expanding the Scope of Hypervalent Iodine Reagents for Perfluoroalkylation: From Trifluoromethyl to Functionalized Perfluoroethyl
Václav Matoušek1, Jiří Václavík2,3, Peter Hájek1
1Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology, ETH Zürich, Vladimir-Prelog-Weg 2, 8093 Zürich (Switzerland).
Abstract:
A series of new hypervalent iodine reagents based on the 1,3-dihydro-3,3-dimethyl-1,2-benziodoxole and 1,2-benziodoxol-3-(1H)-one scaffolds, which contain a functionalized tetrafluoroethyl group, have been prepared, characterized, and used in synthetic applications. Their corresponding electrophilic fluoroalkylation reactions with various sulfur, oxygen, phosphorus, and carbon-centered nucleophiles afford products that feature a tetrafluoroethylene unit, which connects two functional moieties. A related λ(3) -iodane that contains a fluorophore was shown to react with a cysteine derivative under mild conditions to give a thiol-tagged product that is stable in the presence of excess thiol. Therefore, these new reagents show a significant potential for applications in chemical biology as tools for fast, irreversible, and selective thiol bioconjugation.
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