Patent US3884979A successfully refreshed from Google Patents.
US3884979A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Synthesis of unsaturated diketones
Assignee: F Hoffmann La Roche AG
•
Filing: 1971-06-29
•
Granted: 1975-05-20
•
Expires: 1991-06-29
Abstract
Abstract This invention relates to a process for the preparation of 2alkenyl-4-hydroxy-3-methyl-2-cyclopenten-1-ones from the reaction product of 2,4-pentane dione and a 2-propen-or 2-propyn-1-ol derivative including intermediates therein.
Inventors
- 👤 George Buchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 17:38
CPC Classifications
C; C07; C07D; C07D303/00; C07D303/02; C07D303/08; C07C; C07C45/00; C07C45/61; C07C45/62; C07C45/67; C07C45/673; C07C45/68; C07C45/70; C07D303/48
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
9 words
A PROCESS FOR PREPARING A COMPOUND OF THE FORMULA:
Claim 2
Dependent Claim
9 words
A PROCESS FOR PREPARING A COMPOUND OF THE FORMULA:
References Cited (Backward Citations)
US2839579A
Cited
US3493619A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-19 | 1978-11-18 | 1979-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-19 | 1982-11-18 | 1983-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-19 | 1986-11-18 | 1987-05-20 | $7700.00 | Window Closed / Lapsed |