Unlike the reaction with TMSN3, which gave oxetane azide 59 above, the reaction with the harder nucleophile NaN3 gave sulfonyl azide 101 in good yields. Cyclobutane sulfonyl fluorides also underwent the SuFEx with deprotonated amine nucleophiles (102). Phenolates (NaH deprotonation) or phenols with Cs2CO3 generated sulfonate esters in good yields (103, 104). Similarly, sodium trifluoroethanoate underwent SuFEx ( ). As such, we envisage a broad range of SuFEx chemistry is applicable to the OSF reagents when the nucleophiles are sufficiently reactive at room temperature.