US3781313A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sulfone intermediates for the synthesis of vitamin a
Assignee: Rhone Poulenc SA
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Filing: 1971-01-20
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Granted: 1973-12-25
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Expires: 1991-01-20
Abstract
Abstract VITAMIN A ACID AND ITS ESTERS, WHICH ARE KNOWN INTERMEDIATES FOR THE PRODUCTION OF VITAMIN A, ARE MADE BY THE ACTION OF ALKALI ON SULPHONES OF THE FORMULA: 1,1,3-TRI(CH3-),2-(Q-OOC-CH=C(-CH3)-CH2-CH(-SO2-R)-CH= C(-CH3)-CH=CH-)CYCLOHEX-2-ENE WHERE R IS AN ARYL RADICAL AND Q IS HYDROGEN OR AN ORGANIC RADICAL, THEMSELVES MADE BY REACTION OF $HALOGENOSENECIOATES ON SULPHONES OF FORMULA: 1,1,3-TRI(CH3-),2-(R-SO2-CH2-CH=C(-CH3)-CH=CH-)CYCLOHEX- 2-ENE WHICH IN TURN ARE MADE BY THE ACTION OF AN ARYL SULPHINATE ON VINYL-B-IONOL.
Inventors
- 👤 M Julia
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 01:58
CPC Classifications
C; C07; C07C; C07C403/00; C07C403/22; C07C403/04; C07C403/06; C07C403/08; C07C403/20; C07C2601/00; C07C2601/12; C07C2601/16
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-24 | 1977-06-25 | 1977-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-24 | 1981-06-25 | 1981-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-24 | 1985-06-25 | 1985-12-25 | $7700.00 | Window Closed / Lapsed |