Patent ID: 7375253

Claim:
A process for the synthesis of (per)fluorinated mono-functional carbonyl compounds having the following formula: F-A-R F —B—C(O)X 1 (I) wherein: X 1 =F, CF 3 ; A, B equal to or different from each other, are independently C 1 -C 5 (per)fluoroalkylene groups or linear or branched C 1 -C 5 (per)fluorooxyalkylene groups, optionally containing one or more Cl and/or H atoms; R F is selected from the following groups: —ORf 1 O— wherein Rf 1 =C 1 -C 20 perfluoroalkylene; —ORf 2 —, wherein Rf 2 is a perfluorooxyalkylene chain containing one or more of the following units statistically distributed along the backbone: (C 3 F 6 O), selected between (CF 2 CF(CF 3 )O) or (CF—(CF 3 )CF 2 O); (CFX 1 O) wherein X 1 is F or CF 3 ; (C 2 F 4 O); (CF 2 (CF 2 ) x′ CF 2 O) wherein x′ is an integer equal to 1 or 2; (CR 4 R 5 CF 2 CF 2 O) wherein R 4 and R 5 are equal to or different from each other and selected between H, Cl, and wherein one fluorine atom of the perfluoromethylene unit is optionally substitued with H, Cl or (per)fluoroalkyl, having from 1 to 4 carbon atoms; said process comprising the following steps: A) obtainment of the mono-hypofluorite of formula: FO—CFX 2 -A-R F —B—C(O)X 1 (II) by partial fluorination with elemental fluorine of the carbonyl groups of the following (per)fluorinated di-functional carbonyl compound of formula: X 2 (O)C-A-R F —B—C(O)X 1 (III) wherein: X 1 , R F , A and B have the above meanings; X 2 , equal to or different from X 1 , has the same meanings as X 1 ; in the presence of a catalyst based on metal fluorides having formula MeF y , wherein: Me is an alkaline or alkaline-earth metal or Ag; y=1 or 2; B) thermal decomposition of the mono-hypofluorite of formula (II) to give (per)fluorinated mono-functional carbonyl compounds (I), according to the reaction: FO—CFX 2 -A-R F —B—C(O)X 1 (II)- - - →F-A-R F —B—C(O)X 1 (I)+(O)CFX 2 .