Method for preparing polyunsaturated perfluorinated compounds

Patent metadata

Field	Value
Publication number	US-10351493-B2
Application number	US-201716090857-A
Country	US
Kind code	B2
Filing date	Mar 20, 2017
Priority date	Apr 4, 2016
Publication date	Jul 16, 2019
Grant date	Jul 16, 2019

Abstract

The present invention relates to a method for preparing a polyinsaturated perfluorinated compound B from a polyinsaturated perhalogenated compound D having the formula C n X 2(n−m+1) , in which X is independently selected from one of the halogens, F, Cl, Br or I, provided at least one X is not fluorine; n is the number of carbon atoms and is at least higher than or equal to 4, m is the number of double carbon-carbon bonds and is higher than or equal to 2, wherein the method comprises a step in which compound D is fluorinated in the presence of a fluorinating agent of general formula AF p , in which A is hydrogen, an alkali metal or an alkaline earth metal, and p is 1 or 2, and in the presence of an aprotic organic polar solvent; the method being carried out with a molar ratio of AF p to compound D of less than 1.45*2(n−m+1).

First claim

The invention claimed is:

1. A process for preparing a polyunsaturated perfluorinated compound B from a polyunsaturated perhalogenated compound D of formula C n X 2(n−m+1 ) wherein
X is chosen independently from a halogen F, CI, Br or I, provided that at least one X is not a fluorine;
n is the number of carbon atoms and is at least greater than or equal to 4;
m is the number of carbon-carbon double bonds and is greater than or equal to 2;
said process comprising the step of fluorinating the compound D in the presence of a fluorinating agent of general formula AF p wherein A is hydrogen, an alkali metal or an alkaline-earth metal, and p is 1 or 2; and in the presence of an aprotic polar organic solvent; said process being carried out with an AF p /compound D molar ratio of less than 1.30*2(n−m+1).

2. The process as claimed in claim 1 , wherein the compound D is a polyunsaturated perchlorinated compound of formula C n Cl 2(n−m+1 ).

3. The process as claimed in claim 1 , wherein the compound D is hexachlorobutadiene.

4. The process as claimed in claim 1 , wherein the compound B is hexafluorobutadiene.

5. The process as claimed in claim 1 , wherein the AF p /compound D molar ratio is less than 1.15*2(n−m+1).

6. The process as claimed in claim 1 , wherein the fluorinating agent is LiF, KF, NaF, MgF 2 or CaF 2 .

7. The process as claimed in claim 1 , wherein the aprotic polar organic solvent is chosen from the group consisting of an ether, an amide, an amine, a sulfoxide, a ketone, a nitrile and an ester.

8. The process as claimed in claim 1 , wherein the aprotic polar organic solvent is chosen from the group consisting of 1,3-dioxane, 1,4-dioxane, 1,3,5-trioxane, tetrahydrofuran, 1,2-dimethoxyethane, dimethyl sulfoxide, diethyl sulfoxide, N-methylpyrrolidone, dimethylformamide, dimethylacetamide, ethyl acetate, acetone, propanone, 2-pentanone, butanone, n-butyl acetate, triethylamine, pyridine and acetonitrile.

9. The process as claimed in claim 1 , wherein a first stream comprising the compound B, coproducts of the fluorination reaction and optionally of the unreacted compound D is recovered and separated by distillation so as to form a second stream comprising the coproducts of the reaction and the unreacted compound D and a third stream comprising the compound B.

10. The process as claimed in claim 1 , wherein a first stream comprising the compound B, coproducts of the fluorination reaction and unreacted compound D is recovered, and wherein a compound of formula AX p is formed and the unreacted compound D is separated from the compound of formula AX p .

Assignees

• Arkema France

Inventors

• Schmidt Grégory
• Teissier Rémy

Classifications

• C07C17/208 Primary

  the other compound being MX · CPC title

• C07C21/20

  Halogenated butadienes · CPC title

• C07C17/206

  the other compound being HX · CPC title

• C07C21/18

  containing fluorine · CPC title