Conversion of trifluoromethyls into esters along with polyether upcycling via cation-transfer-catalyzed C-O/C-F...

Ester and trifluoromethyl groups play crucial roles in chemistry and drug design. However, the implementation of interconversion from a trifluoromethyl into an ester under wide conditions is not an easy task, because the C-F bond of the trifluoromethyl group possesses high bond energy and is extremely difficult to break. Herein, we present for the first time a silylium-ion-initiated method for intermolecular C-F/C-O metathesis, enabling selective activation of inert C(sp³)-F and C(sp³)-O bonds. This approach facilitates the defluoroalkoxylation of trifluoromethyl-substituted substrates and polyfluoroalkanes when combined with ethers or polyethers, thus building a bridge to convert trifluoromethyl groups into ester/ketone groups, along with polyether upcycling. We provide crystallographic evidence that clearly confirms that this reaction involves the formation of silyloxonium ions and Meerwein-type salt intermediates, followed by cationic ligand transformations.