Process for producing fluorinated compound

1. A process for producing a fluorinated compound, the process comprising:

(I) reacting a compound (1) of formula (1) and a compound (2) of formula (2) to produce a compound (3) of formula (3), wherein a fluorine content is at least 30 mass %;

(II) fluorinating the compound (3) in a liquid phase to produce a compound (4) of formula (4),

HOCH 2 —R A —CH 2 OH  (1)

X 1 C(═O)—C(R B )(R C )(R D )  (2)

(R D )(R C )(R B )C—C(═O)OCH 2 —R A —CH 2 OC(═O)—C(R B )(R C )(R D )  (3)

(R DF )(R CF )(R BF )C—C(═O)OCF 2 —R AF —CF 2 OC(═O)—C(R BF )(R CF )(R DF )  (4)

wherein

R A : a bivalent saturated hydrocarbon group or a partially halogenated bivalent saturated hydrocarbon group,

R B , R C and R D : R B is the same fluorinated monovalent organic group as R BF , a monovalent organic group to be converted to R BF by a fluorination reaction, a hydrogen atom or a halogen atom; R C is the same fluorinated monovalent organic group as R CF or a monovalent organic group to be converted to R CF by a fluorination reaction; and R D is the same fluorinated monovalent organic group as R DF or a monovalent organic group to be converted to R DF by a fluorination reaction,

X 1 : a halogen atom,

R AF : a group having all hydrogen atoms in R A substituted by fluorine atoms,

R BF : when R B is a hydrogen atom, R BF is a fluorine atom; when R B is a halogen atom, R BF is the same halogen atom as R B ; and when R B is neither a hydrogen atom nor a halogen atom, R BF is a fluorinated monovalent organic group which is the same as or different from R B , and when different, R BF is a group which is R B fluorinated,

R CF : a fluorinated monovalent organic group which is the same as or different from R C , and when different, R CF is a group which is R C fluorinated, and

R DF : a fluorinated monovalent organic group which is the same as or different from R D , and when different, R DF is a group which is R D fluorinated;

(III) subjecting the compound (4) to a cleavage reaction to obtain a compound (5) of formula (5):

FC(═O)—R AF —C(═O)F  (5); and

either performing (IVa) and (V) or performing (IVb):

(IVa) reacting the compound (5) with hexafluoropropylene oxide to obtain a compound (7) of formula (7) and

(V) heat-decomposing the compound (7) to obtain a compound (8) of formula (8):

FC(═O)—CF(CF 3 )—O—CF 2 —R AF —C(═O)F  (7)

F 2 C═CF—O-Q AF -CF═CF 2   (8)

wherein

Q AF : when the number of carbon atoms of R AF is 1, Q AF is a single bond; when the number of carbon atoms of R AF is at least 2, Q AF is a group of which the number of carbon atoms is less by 1 than R AF and wherein all hydrogen atoms in a saturated bivalent hydrocarbon group or a partially halogenated bivalent hydrocarbon group are substituted by fluorine atoms; or

(IVb) reacting the compound (5) with a compound (9) of formula (9) to obtain a compound (10) of formula (10):

HO—R  (9)

R—OC(═O)—R AF —C(═O)O—R  (10)

wherein R is a group selected from the group consisting of —CH 3 , —CH 2 CH 3 and —CH(CH 3 ) 2 .

2. The process for producing a fluorinated compound according to claim 1 , wherein

the number of carbon atoms of R A is at most 20, and

when each of R B , R C and R D is the fluorinated monovalent organic group or the monovalent organic group, the number of carbon atoms thereof is at most 10.

3. The process for producing a fluorinated compound according to claim 1 , wherein R A is (CH 2 ) n , and R AF is (CF 2 ) n , wherein n is an integer of from 1 to 10.

4. The process for producing a fluorinated compound according to claim 1 , wherein

R B and R BF are fluorine atoms,

R C and R CF are the same C 1-3 perfluoroalkyl groups, and

R D and R DF are the same C 1 perfluoroalkyl groups, the same C 2-6 perfluoroalkoxyl groups or the same C 4-8 perfluoroalkoxyl groups having one etheric oxygen atom.

5. The process for producing a fluorinated compound according to claim 1 , wherein in the fluorinating (II), the fluorination is carried out by supplying a fluorine gas diluted with an inert gas, into the liquid phase, and the proportion of the fluorine gas is from 30 to 60 vol % in the total 100 vol % of the inert gas and the fluorine gas.

6. The process for producing a fluorinated compound according to claim 1 , wherein the fluorination is carried out in the liquid phase containing a fluorination reaction solvent, and the fluorination reaction solvent is a fluorinated solvent having no C—H bond and having an etheric oxygen atom.

7. The process for producing a fluorinated compound according to claim 6 , wherein the fluorinated solvent is (R DF )(R CF )(R BF )C—C(═O)F.

8. The process for producing a fluorinated compound according to claim 1 , wherein in the fluorinating (II), the fluorination is carried out in the liquid phase containing a fluorination reaction solvent, and the fluorination reaction solvent is the compound (5).

9. The process for producing a fluorinated compound according to claim 1 , the process further comprising:

(IVa) reacting the compound (5) with hexafluoropropylene oxide to obtain the compound (7) of formula (7) and

(V) heat-decomposing the compound (7) to obtain the compound (8) of formula (8).

10. The process for producing a fluorinated compound according to claim 1 , the process comprising:

(IVb) reacting the compound (5) with the compound (9) of formula (9) to obtain the compound (10) of formula (10).

11. The process for producing a fluorinated polymer according to claim 9 , further comprising:

polymerizing the compound (8).

12. The process for producing a fluorinated compound according to claim 1 , wherein the compound (2) is selected from the group consisting of:

(CF 3 ) 2 CFC(═O)F  (2-1)

CF 3 CF 2 CF 2 OCF(CF 3 )CF 2 OCF(CF 3 )C(═O)F  (2-2)

CF 3 CF 2 CF 2 OCF(CF 3 )C(═O)F  (2-3)

CF 2 ClCFClCF 2 CF 2 OCF(CF 3 )C(═O)F  (2-4)

CF 2 BrCF 2 OCF(CF 3 )C(═O)F  (2-5)

CF 2 ClCFClCF 2 CF(CF 3 )OCF(CF 3 )C(═O)F  (2-6)

CH 3 CH 2 CH 2 OCF(CF 3 )C(═O)F  (2-7).

13. The process for producing a fluorinated compound according to claim 12 , wherein the compound (1) is:

HOCH 2 —(CH 2 ) n —CH 2 OH  (1-1),

wherein n is from 2 to 8.

14. The process for producing a fluorinated compound according to claim 1 , wherein in the reacting (I), an amount of the compound (2) per the compound (1) is from 2 to 5 times by mole.

15. The process for producing a fluorinated compound according to claim 13 , wherein in the reacting (I), an amount of the compound (2) per the compound (1) is from 2 to 5 times by mole.

16. The process for producing a fluorinated compound according to claim 1 , wherein the compound (2) is selected from the group consisting of:

(CF 3 ) 2 CFC(═O)F  (2-1)

CF 3 CF 2 CF 2 OCF(CF 3 )CF 2 OCF(CF 3 )C(═O)F  (2-2)

CF 3 CF 2 CF 2 OCF(CF 3 )C(═O)F  (2-3).