1- perfluoropropene, hydrolysis

Sodium nitrite in dimethylformamide acts as a nucleophile and reacts with perfluoropropene to generate a perfluoroalkyl nitrite anion The intermediate carbanion undergoes intramolecular nitrosation with loss of carbonyl difluoride to give tnfluoroacetic acid upon hydrolysis [5] (equation 6)... 

The cydo-adducts (80) may be intermediates in u.v.-induced reactions between sulphur dioxide and tetrafluoroethylene or perfluoropropene described recently . Formation of the final products, perfluoro-l-fluorocar-bonylalkanesulphinyl fluorides (81), is readily envisioned to occur via fluoride-initiated ring-opening of these cyclo-adducts (80), small amounts of fluoride ion being generated initially through hydrolysis of the adducts by adventitious moisture. 

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