Abstract: In preparing a fluoroalkylsulfonate RfSO.sub.3 M, where Rf is a perfluoroalkyl gruop having not more than 6 carbon atoms and M is an alkali metal, by neutralization reaction between a fluoroalkylsulfonic acid RfSO.sub.3 H and an alkali metal carbonate or hydroxide, the reaction is carried out under acidic conditions such that at the end of the reaction pH of the reaction liquid is lower than 6, and preferably not higher than 3. By so maintaining the reaction liquid acidic, the obtained RfSO.sub.3 M becomes very low in the concentrations of anionic impurities such as free fluorine, free chlorine and carbonate radical and, besides becomes low in moisture absorbency.

Abstract: Water soluble, substantially nontoxic salts of compounds of the formula:CF.sub.3 Rwherein R is --SO.sub.3 H, --SO.sub.2 NH.sub.2 or --PO.sub.3 H.sub.2, are useful for obtaining fluorine magnetic resonance images of body organs and tissues. Illustrative salts of such compounds include sodium trifluoromethane sulfonate, N-methylglucaminium trifluoromethanesulfonate and N-methylglucaminium trifluoromethanesulfonamide.

Abstract: A process for the preparation of perhaloalkanesulfinic and -sulfonic acids and derivatives of these acids. A perhaloalkanesulfinic acid salt is prepared by contacting a metal hydroxymethanesulfinate (preferably, a sodium, zinc or copper hydroxymethanesulfinate) with a perhaloalkyl halide group, in a polar solvent. Optionally, the perhaloalkanesulfinic acid salt is then converted to a perhaloalkanesulfinic or -sulfonic acid or a derivative of either of these acids.