Patent US2692898A successfully refreshed from Google Patents.
US2692898A
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Process for the preparation of tetrahydrofluorenone
Assignee: Organon NV
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Filing: 1951-11-20
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Granted: 1954-10-26
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Expires: 1971-11-20
Abstract
No abstract record available.
Inventors
- 👤 Beyerman Hugo Christiaan
- 👤 Veer Willem Louis Constantijn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:46
CPC Classifications
C; C07; C07C; C07C49/00; C07C49/587; C07C49/657; C07C49/683; C07C51/00; C07C51/58; C07C51/60
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
13 words
AS A NEW COMPOUND 1,2,3,4-TETRAHYDROFLUORENONE OF THE GENERAL FORMULA C13H12O, THE STRUCTURAL FORMULA
Claim 2
Dependent Claim
13 words
AS A NEW COMPOUND 1,2,3,4-TETRAHYDROFLUORENONE OF THE GENERAL FORMULA C13H12O, THE STRUCTURAL FORMULA
Claim 3
Dependent Claim
18 words
IN A PROCESS OF PREPARING 1,2,3,4-TETRAHYDROFLUORENONE, THE STEP COMPRISING REACTING A 2PHENYL-3,4,5,6-TETRAHYDROBENZOIC ACID COMPOUND OF THE FOLLOWING FORMULA
Claim 4
Dependent Claim
18 words
IN A PROCESS OF PREPARING 1,2,3,4-TETRAHYDROFLUORENONE, THE STEP COMPRISING REACTING A 2PHENYL-3,4,5,6-TETRAHYDROBENZOIC ACID COMPOUND OF THE FOLLOWING FORMULA
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) | 1957-10-25 | 1958-04-26 | 1958-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-10-25 | 1962-04-26 | 1962-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-10-25 | 1966-04-26 | 1966-10-26 | $7700.00 | Window Closed / Lapsed |