Patent ID: 7709665

Claim:
A process for producing a fluorosulfonyl group-containing compound (5), wherein said process comprises: fluorinating compound (3) to form a perfluorinated compound (4); and decomposing the perfluorinated compound (4) to produce the fluorosulfonyl group-containing compound (5): provided that the symbols in the formulae have the following meanings: R A : a bivalent organic group; R AF : fluorinated R A ; R B , R C , R D : each independently represent a hydrogen atom, a fluorine atom or a monovalent organic group; R BF , R CF , R DF : a fluorine atom corresponding to each R B , R C , R D that is a hydrogen atom or a fluorine atom; or a fluorinated monovalent organic group corresponding to each R B , R C , R D that is a monovalent organic group; R E : a monovalent organic group; R EF : fluorinated R E ; E: a bivalent connecting group; E F : fluorinated E; E F1 : a group formed by scission of E F ; X 1 , X 2 , X 3 : each independently represent a hydrogen atom or a fluorine atom; X 1F , X 2F , X 3F : a fluorine atom corresponding to each of X 1 , X 2 , X 3 that is a hydrogen atom or a fluorine atom; wherein at least one of R A , R B , R C , R D , R E , X 1 , X 2 , X 3 , and E is a hydrogen atom or a group having at least one hydrogen atom, and wherein R AF , R BF , R CF , R DF , R EF , X 1F , X 2F , X 3F , and E F is a fluorinated group or a fluorine atom.