Patent US4859809A successfully refreshed from Google Patents.
US2811558A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of z-methyl i
Assignee: —
•
Filing: —
•
Granted: 1957-10-29
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Expires: 1974-10-29
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 06:10
CPC Classifications
C; C07; C07C; C07C45/00; C07C45/61; C07C45/67; C07C45/68; C07C45/70; C07C45/71
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
73 words
A PROCESS FOR THE PREPARATION OF 2-METHYLCYCLOPENTANE-1:3-DIONE WHICH COMPRISES REACTING 3-METHYLCYCLOPENTANE-1:2:4-TRIONE WITH A SUBSTANTIALLY EQUIMOLECULAR QUANTITY OF A COMPOUND R-NH-NH2 (WHEREIN R REPRESENTS A MEMBER OF THE CLASS CONSISTING OF HYDROGEN AND THE GROUPS CONH2 AND CSNH2), DECOMPOSING THE PRODUCT OF REACTION BY HEATING IT IN A SOLUTION OF CAUSTIC ALKALI IN A SOLVENT HAVING A BOILING POINT OF AT LEAST 170*C. AT ATMOSPHERIC PRESSURE AND ACIDIFYING THE ALKALI METAL SALT THUS FORMED.
Claim 2
Dependent Claim
73 words
A PROCESS FOR THE PREPARATION OF 2-METHYLCYCLOPENTANE-1:3-DIONE WHICH COMPRISES REACTING 3-METHYLCYCLOPENTANE-1:2:4-TRIONE WITH A SUBSTANTIALLY EQUIMOLECULAR QUANTITY OF A COMPOUND R-NH-NH2 (WHEREIN R REPRESENTS A MEMBER OF THE CLASS CONSISTING OF HYDROGEN AND THE GROUPS CONH2 AND CSNH2), DECOMPOSING THE PRODUCT OF REACTION BY HEATING IT IN A SOLUTION OF CAUSTIC ALKALI IN A SOLVENT HAVING A BOILING POINT OF AT LEAST 170*C. AT ATMOSPHERIC PRESSURE AND ACIDIFYING THE ALKALI METAL SALT THUS FORMED.
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) | 1960-10-28 | 1961-04-29 | 1961-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-10-28 | 1965-04-29 | 1965-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-10-28 | 1969-04-29 | 1969-10-29 | $7700.00 | Window Closed / Lapsed |