Making the SF₅ Group More Accessible: A Gas-Reagent-Free Approach to Aryl Tetrafluoro-λ⁶ -sulfanyl Chlorides

Modern pentafluorosulfanyl (SF₅ ) chemistry has an Achilles heel: synthetic accessibility. Herein, we present the first approach to aryl-SF₄ Cl compounds (key intermediates in state-of-the-art aryl-SF₅ synthesis) that overcomes the reliance on hazardous fluorinating reagents and/or gas reagents (e.g. Cl₂ ) by employing easy-to-handle trichloroisocyanuric acid, potassium fluoride, and catalytic amounts of acid. These simple, mild conditions allow direct access to aryl-SF₄ Cl intermediates that either have not been or cannot be demonstrated using previous methods. Furthermore, the same approach provides access to aryl-SF₃ and aryl-SeF₃ compounds, which extend the applications of this chemistry beyond arene SF₅ -functionalization, and demonstrate its ability to address a more general oxidative fluorination problem.