Abstract: | Using P. T. C. or cosolvents, both perfluoroalkyl iodides such as Cl(CF2),nI (n=2, 4, 6, 1a-1c), H(CF2)8I (1d), CF3(CF2)nI (n=3, 5, 7, 1e-1g), and α. ω-perfluoroalkylene diiodides such as (ICF2CF2)2O (4a), I (CF2)nI (n=6, 8, 10, 4b-4d) reacted smoothly with sodium dithionite in aqueous solution under mild conditions to give the corresponding perfluoroalkanesulfinates Cl(CF2)nSO2Na (n=2, 4, 6, 2a-2c), H(CF2)8SO2Na (2d), CF3(CF2)nSO2Na (n=3, 5, 7, 2e-2g), α, ω-perfluoroalky-lenedisulfinates O (CF2CF2SO2K)2 (5a), and KO2S(CF2)nSO3K (n=6, 8, 10, 6b-6d) in moderate to high yields. These sulfinates were converted to the corresponding sulfonyl chlorides by reacting with chlorine in the usual way. Thus the discovery of the new reagent renders sulfinatodeiodination a practical method for the synthesis of perfluorosulfinic and perfluorosulfonic acids and their derivatives from the corresponding perfluoroalkyl iodides. |