Multifaceted ion exchange resin-supported hydrogen fluoride: a path to flow hydrofluorination

A solid anhydrous hydrogen fluoride equivalent was prepared by mixing HF gas with an inexpensive anion exchange resin (A26-HF, HF content 30% wt/wt). This reagent is capable of hydrofluorinating alkenes, of ring-opening aziridines to give fluoroamines, and of yielding fluorotetrahydropyrans through a fluoro-Prins reaction, all with high selectivity under mild conditions. Our ion exchange resin supported HF reagent could be easily packed into a plastic column and used in flow fluorinations.