US3776960A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of bis(perfluoroalkyl-sulfonyl)methanes
Assignee: 3M Co
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Filing: 1971-12-09
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Granted: 1973-12-04
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Expires: 1991-12-09
Abstract
Abstract A PROCESS IS PROVIDED FOR OBTAINING IMPROVED YIELDS OF BIS(PERFLUORALKYLSULFONYL)ETHANES Y THE REACTION OF PERFLUOROALKANESULFONYL FLUORIDES WITH METHYLMAGNESIUM HALIDE USING A NON-REACTIVE ETHER FORMING AN OXONIUM ION IN AQUEOUS SULFURIC ACID HAVING AN IONIZATION CONSTANT AS EXPRESSED BY PHA OF GREATER THAN -3.3.
Inventors
- 👤 R Koshar
- 👤 R Mitsch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:05
CPC Classifications
C; C08; C08G; C08G59/00; C08G59/18; C08G59/68; C08G59/687; C07; C07C; C07C315/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-03 | 1977-06-04 | 1977-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-03 | 1981-06-04 | 1981-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-03 | 1985-06-04 | 1985-12-04 | $7700.00 | Window Closed / Lapsed |