Patent US4874901A successfully refreshed from Google Patents.
US4874901A
Expired / Lapsed
US
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Process for the production of polyfluorinated ethers
Assignee: Datex Ohmeda Inc
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Filing: 1988-05-06
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Granted: 1989-10-17
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Expires: 2008-05-06
Abstract
Abstract Sodium or potassium fluoride has been found to efficiently fluorinate the chloro atom adjacent the ether oxygen in chloro-fluoro organic ethers. The reaction proceeds efficiently without added solvent at an elevated temperature and pressure.
Inventors
- 👤 Donald F. Halpern
- 👤 Mark L. Robin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:13
CPC Classifications
C; C07; C07C; C07C41/00; C07C41/01; C07C41/18; C07C41/22; A; A61; A61P; A61P23/00; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/582
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
83 words
A method for the fluorination of a compound of the formula: ##STR2## wherein X 1 , X 2 and X 3 are hydrogen, chloro, or fluoro, with the proviso that at least one is chloro and R 1 and R 2 are either hydrogen or halo lower alkyl with the proviso that at least one is halo lower alkyl, said method comprising reacting sodium fluoride or potassium fluoride with said compound at an elevated temperature and pressure in the absence of added solvent.
Claim 2
Independent Claim
83 words
A method for the fluorination of a compound of the formula: ##STR2## wherein X 1 , X 2 and X 3 are hydrogen, chloro, or fluoro, with the proviso that at least one is chloro and R 1 and R 2 are either hydrogen or halo lower alkyl with the proviso that at least one is halo lower alkyl, said method comprising reacting sodium fluoride or potassium fluoride with said compound at an elevated temperature and pressure in the absence of added solvent.
Claim 3
Dependent Claim
26 words
A method according to claim 1, wherein R 1 and R 2 are either hydrogen or trifluoromethyl with the proviso that at least one is trifluoromethyl.
Claim 4
Dependent Claim
11 words
A method according to claim 1, wherein said compound is isoflurane.
Claim 5
Dependent Claim
24 words
A method according to claim 1, wherein said compound is (CF 3 ) 2 CHOCHCl 2 or (CF 3 ) 2 CHOCH 2 Cl.
Claim 6
Dependent Claim
24 words
A method according to claim 1, wherein the sodium fluoride or potassium fluoride is neither dried nor activated prior to use in the reaction.
Claim 7
Dependent Claim
12 words
A method according to claim 3, wherein isoflurane is converted to 2-(difluoromethoxy)-1,1,1,2-tetrafluoroethane.
Claim 8
Dependent Claim
13 words
A method according to claim 4, wherein said compound is converted to sevoflurane.
Claim 9
Dependent Claim
18 words
A method according to claim 1, wherein the temperature is in the range of 100° to 300° C.
Claim 10
Dependent Claim
18 words
A method according to claim 8, wherein the temperature is in the range of 150° to 250° C.
Claim 11
Dependent Claim
18 words
A method according to claim 1, wherein the pressure is in the range of 15 to 1100 psig.
Claim 12
Dependent Claim
17 words
A method according to claim 10, wherein the pressure is in the range 40 to 600 psig.
Claim 13
Dependent Claim
23 words
A method according to claim 1, wherein the molar ratio of said sodium fluoride or potassium fluoride to said compound is about 1:1.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-16 | 1993-04-17 | 1993-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-16 | 1997-04-17 | 1997-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-16 | 2001-04-17 | 2001-10-17 | $7700.00 | Window Closed / Lapsed |