2-Hydroperfluoropropyl azide—a versatile reagent for the oxidative fluorination of organic compounds of trivalent phosphorus

2-Hydroperfluoropropyl azide CF₃CHFCF₂N₃, 1 , an inexpensive, readily available, and stable (easy to store) compound, is suggested as an effective fluorinating reagent for different classes of trivalent organophosphorus compounds in accordance with the general scheme R₃P → R₃PF₂. Generally, the reactions are performed without solvent, the highly volatile CF₃ CHFCN being the main by-product. The fluorination is usually an exothermic process, but slight heating is necessary in the case of alkyldifluorophosphites. The unusual Arbuzov rearrangement, accompanied by isomerization of an isobutyl or neopentyl group into a tert-group, ROPF₂ → t-R′POF₂, under the action of a catalytic amount of 1 , was observed.