Process for producing fluorinated alcohols
View Patent ↗The present invention is directed to a process for preparation of fluorinated alcohols of Formula (I) R f CH 2 CH 2 OH (I) by contacting a fluorinated iodide with an alkyl vinyl ether in the presence of an initiator and a base to generate an intermediate hemi-acetal or aldehyde or a mixture thereof, followed by hydrogenation of the hemi-acetal of Formula (II) R f CH 2 CH(OC x H 2x+1 ) m (OH) p (II) or aldehyde of Formula (III) R f CH 2 CHO (III) or a mixture thereof, to yield a compound of Formula (I).
1. A process for preparation of a compound of Formula (I)
R f CH 2 CH 2 OH (I)
wherein
R f is linear or branched C n F 2n+1 optionally interrupted by at least one oxygen, CH 2 , CH 2 CH 2 , or CH 2 CF 2 ; and
n is 1 to 10;
comprising
a) contacting a compound of formula R f I, wherein R f is defined as above, with an alkyl vinyl ether containing 1 to 4 carbons in the alkyl, in the presence of an initiator and a base to generate a mixture of intermediates comprising an hemi-acetal of Formula (II) and an aldehyde of Formula (III)
R f CH 2 CH(OC x H 2x+1 ) m (OH) p (II)
R f CH 2 CHO (III)
wherein R f is defined as above, m is 0 to 1; and p is 1 to 2; provided that m+p is 2; and x is 1 to 4; and
b) hydrogenating, under acidic conditions, the mixture comprising the hemi-acetal of Formula (II) and aldehyde of Formula (III) to yield a compound of Formula (I).
2. The process of claim 1 wherein the ratio of alkyl vinyl ether to R f I is from about 1:1 to about 2:1.
3. The process of claim 1 wherein the alkyl vinyl ether is of the formula CH 2 ═CHOC x H 2x+1 wherein x is 1 to 4.
4. The process of claim 1 wherein the alkyl vinyl ether is selected from the group consisting of methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, i-propyl vinyl ether, n-butyl vinyl ether, sec-butyl ether, tert-butyl vinyl ether, and isobutyl vinyl ether.
5. The process of claim 1 wherein the initiator is an oxide, sulfite, sulfinate or nitrate.
6. The process of claim 1 wherein the initiator is selected from the group consisting of benzoyl peroxide, sodium hydrosulfite, thiourea dioxide, sodium metabisulfite, sodium hydroxymethanesulfinate, ammonium cerium(IV) nitrate and potassium ferricyanide.
7. The process of claim 1 wherein the base is an oxide, hydroxide, carbonate, sulfite or phosphate.
8. The process of claim 7 wherein the base is selected from the group consisting of sodium bicarbonate, sodium bisulfite, calcium oxide, sodium carbonate, potassium carbonate, sodium pyrophosphate, potassium hydroxide, and sodium hydroxide.
9. The process of claim 1 wherein the contacting of R f I with an alkyl vinyl ether is conducted at ambient temperature.
10. The process of claim 1 wherein the contacting of R f I with an alkyl vinyl ether is in a solvent selected from the group consisting of tetrahydrofuran, tetrahydropyran, and glyme.
11. The process of claim 1 wherein the hydrogenating of the mixture of intermediates comprising the hemi-acetal of Formula (II) and aldehyde of Formula (III) is in the presence of 1) an aqueous acid and 2) a catalyst selected from the group consisting of ruthenium, platinum, copper, and combinations thereof.
12. The process of claim 1 wherein the hydrogenating of the mixture of intermediates comprising the hemi-acetal of Formula (II) and aldehyde of Formula (III) is in the presence of a catalyst selected from the group consisting of ruthenium, platinum, copper, and combinations thereof.
13. The process of claim 11 wherein the ruthenium or platinum catalyst is supported on carbon or aluminum oxide, and wherein the copper catalyst is supported on zinc oxide or chromium oxide.
14. The process of claim 12 wherein the ruthenium or platinum catalyst is supported on carbon or aluminum oxide, and wherein the copper catalyst is supported on zinc oxide or chromium oxide.
15. The process of claim 11 wherein the aqueous acid is selected from the group consisting of sulfuric acid and phosphoric acid.
16. The process of claim 11 conducted at a temperature ranging from about 25° C. to about 200° C., and a pressure at from about atmospheric to about 600 psi (4.14 MPa).
17. The process of claim 12 conducted at a temperature ranging from about 25° C. to about 200° C., and a pressure at from about atmospheric to about 600 psi (4.14 MPa).
18. The process of claim 1 wherein for R f , n is 1 to 6.
19. The process of claim 1 wherein R f is interrupted by 1 or 2 oxygen atoms.
20. The process of claim 1 wherein the alcohol of Formula (I) is generated with an overall yield of the whole process of greater than 75%.