Perfluorooxosulfate Salts as SOF <sub>4</sub> ‐Gas‐Free Precursors to Multidimensional SuFEx Electrophiles
Armir Zogu, Karim Ullah, Stefanos Spanopoulos, Ermal Ismalaj, Wim M. De Borggraeve, Joachim Demaerel
Abstract
Abstract Sulfur(VI) Fluoride Exchange (SuFEx) chemistry stands as a well‐established method for swiftly constructing complex molecules in a modular fashion. An especially promising segment of this toolbox is reserved for multidimensional SuFEx hubs: three or more substituents pluggable into a singular S VI centre to make ‘beyond‐linear’ clicked constructions. Sulfurimidoyl difluorides (RNSOF 2 ) stand out as the prime example of this, however their preparation from the scarcely available thionyl tetrafluoride (SOF 4 ) limits this chemistry to only a few laboratories with access to this gas. In this work, we identify silver pentafluorooxosulfate (AgOSF 5 ) as a viable SuFEx hub with reactivity equal to SOF 4 . The AgF 2 ‐mediated oxidation of SOCl 2 gives rise to the hexacoordinate AgOSF 5 adduct, which in contact with primary amines produces the sulfurimidoyl fluorides in high yields. In addition, we have found this workflow to be fully extendable to the trifluoromethyl homologue, AgOSF 4 CF 3 , and we propose the use of AgOSF 4 X salts as a general route to azasulfur SuFEx electrophiles from commercial starting materials.