Polyfluorosulfonamido amine and intermediate

Abstract

Current methods for making polyfluorosulfonamido amines, which involve the use of a diamine reactant, provide low yields and produce an undesirable fluorine containing bis-sulfonamide by-product representing an economic loss. The bis-sulfonamide by-product is particularly undesirable because it shares very similar physical properties with the desired monoamine product thus making isolation of the desired polyfluorosulfonamido amine product difficult and costly. Furthermore, instead of the efficient incorporation of fluorine to make the desired polyfluorosulfonamido amine product, the bis-sulfonamide by-product constitutes a substantial loss of costly fluorinated starting material. The bis-sulfonamide by-product also constitutes an undesirable impurity that can worsen surfactancy, repellency, or other performance characteristics of the desired polyfluorosulfonamido amine product. The present invention provides a method of making a polyfluorosulfonamido amine without the production of a bis-sulfonamide by-product by reacting a polyfluoroalkylsulfonic compound with a monoamino amide rather than with a diamine reactant as in previously known methods.