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US4287124A
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Process for the preparation of 4,5-perfluoro-1,3-dioxalanes
Assignee: Hoechst AG
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Filing: 1980-02-19
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Granted: 1981-09-01
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Expires: 2000-02-19
Abstract
Abstract 4,5-Perfluoro-1,3-dioxolanes prepared by the described process have an anesthetic effect.
Inventors
- 👤 Gunter Siegemund
- 👤 Herbert Muffler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:32
CPC Classifications
C; C07; C07D; C07D317/00; C07D317/08; C07D317/10; C07D317/32; C07D317/42
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
103 words
A process for the manufacture of 4,5-perfluoro-1,3-dioxolanes of the formula ##STR12## in which X and Y, independent of one another, are fluorine or trifluoromethyl and R 1 and R 2 are hydrogen or methyl, which comprises reacting a 2-(α-chloroalkoxy)-perfluorocarboxylic acid halide of the formula R.sup.1 R.sup.2 CCl--O--CXY--COZ in which X, Y, R 1 and R 2 are as defined above and Z is chlorine or fluorine, with a fluoride selected from the group consisting of potassium fluoride, cesium fluoride, ammonium fluoride and alkylammonium fluoride, under anhydrous conditions, the reaction being conducted at a temperature in the range of from 0° to 120° C.
Claim 2
Dependent Claim
103 words
A process for the manufacture of 4,5-perfluoro-1,3-dioxolanes of the formula ##STR12## in which X and Y, independent of one another, are fluorine or trifluoromethyl and R 1 and R 2 are hydrogen or methyl, which comprises reacting a 2-(α-chloroalkoxy)-perfluorocarboxylic acid halide of the formula R.sup.1 R.sup.2 CCl--O--CXY--COZ in which X, Y, R 1 and R 2 are as defined above and Z is chlorine or fluorine, with a fluoride selected from the group consisting of potassium fluoride, cesium fluoride, ammonium fluoride and alkylammonium fluoride, under anhydrous conditions, the reaction being conducted at a temperature in the range of from 0° to 120° C.
Claim 3
Dependent Claim
33 words
The process of claim 1, wherein the fluoride reacted is present in an excess of 10 to 50 mol %, calculated on the gram-atoms of chlorine present per mol of 2-(α-chloroalkoxy)-perfluorocarboxylic acid halide.
Claim 4
Dependent Claim
19 words
The process of claim 1, wherein said reaction is carried out in the presence of an aprotic polar solvent.
Claim 5
Dependent Claim
25 words
The process of claim 3, wherein said aprotic polar solvent is selected from the group consisting of nitrile, acid amide, polyether, dimethyl sulfoxide and sulfolane.
Claim 6
Dependent Claim
26 words
The process of claim 3, wherein said aprotic polar solvent is selected from the group consisting of nitrile, dimethyl formamide, dioxane and diethylene glycol dimethyl ether.
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) | 1984-08-31 | 1985-03-02 | 1985-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-31 | 1989-03-02 | 1989-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-31 | 1993-03-02 | 1993-09-01 | $7700.00 | Window Closed / Lapsed |