SYNTHESIS OF THREE PARTIALLY FLUORINATED ALKANESULFONIC ACIDS AS POTENTIAL FUEL-CELL ELECTROLYTES.

Article abstract of DOI:10.1021/je00025a039

The simple and effective syntheses of CH//2FCH//2SO//3H, CF//3CH//2SO//3H, AND CHF//2CF//2CH//2SO//3H have been achieved with 18. 8%, 34. 1%, and 33. 7% overall yields. The low molecuar weight partially fluorinated alkanesulfonic acids containing alpha -methylene groups can be prepared from the p-toluenesulfonates of the corresponding alcohols, via a reaction with benzyl mercaptan, followed by an oxidative chlorination of the resulting sulfides, with subsequent hydrolysis of the sulfonyl chloride. The reaction of partially fluorinated alkyl halides with sodium sulfite (Strecker's method) proved to be inefficient (very low yields) and unreliable. The sulfonate salts formed are difficult to recover and purify.