PyFluor (Pyridine-2-sulfonyl Fluoride)

Technical Specifications

Product Description & Scientific Applications

PyFluor (pyridine-2-sulfonyl fluoride) is an inexpensive, thermally stable deoxyfluorination reagent that converts primary and secondary alcohols to the corresponding fluorides.

Deoxyfluorination. It fluorinates a broad substrate range without the elimination byproducts that limit DAST, which keeps purification straightforward and the method scalable, and it is preferable to the explosive perfluoroalkanesulfonyl fluorides. Reactions run at room temperature in toluene or ethereal solvents with a strong amidine or guanidine base — DBU or MTBD — and tolerate phthalimides, heterocycles, and protected, tertiary and unprotected amines and anilines. The reaction proceeds through the sulfonate ester; on some substrates that ester forms but does not go on to the fluoride.

Handling. The melting point is close to ambient, so the reagent is often dispensed as a liquid and is most easily weighed after warming in a water bath. An exotherm is sometimes observed on addition of base, corresponding to sulfonate ester formation. Reaction progress is accompanied by pale yellow to dark orange precipitates.

Radiofluorination. The fluorine-18 labelled reagent enabled the first no-carrier-added deoxy-radiofluorination, reaching PET tracers directly from alcohols.

As a coupling substrate. Suzuki–Miyaura coupling with hetero(aryl) boronic acids and their pinacol esters gives 2-arylpyridines, with the sulfonyl fluoride as leaving group and tolerance of water and oxygen.

Shipping Destinations

• EU: Priority delivery, 3–5 business days.