General Cascade Esterification-Pentafluorosulfanyloxylation of Carboxylic Acids with Cyclic Ethers using Silver...

As the analog of the trifluoromethoxy (OCF₃) group, the pentafluorosulfanyloxy group (OSF₅) exhibits comparable electronic properties and unique geometry. Previous research has primarily focused on pentafluorosulfanyloxylation of aryl-based substrates; however, a similar transformation in alkyl substrates is exceedingly rare. In this work, we report the first cascade esterification of carboxylic acids with cyclic ethers to achieve the selective synthesis of alkyl-OSF₅ products. In this transformation, AgOSF₅ serves as the pentafluorosulfanyloxide source, cyclic ethers act as the coupling partners, and the acyl bromide is generated from carboxylic acids. This method tolerates a broad range of carboxylic acids and cyclic ethers, delivering excellent functional group compatibility and consistently high yields.