Patent US2658910A successfully refreshed from Google Patents.
US2658910A
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Process for preparing 1, 2, 3, 4-tetrahydrophenanthrenes
Assignee: Wisconsin Alumni Research Foundation
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Filing: 1950-12-15
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Granted: 1953-11-10
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Expires: 1970-12-15
Abstract
No abstract record available.
Inventors
- 👤 William S Johnson
- 👤 Daniel L Turner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:06
CPC Classifications
C; C07; C07C; C07C69/00; C07C69/608; C07C2603/00; C07C2603/02; C07C2603/04; C07C2603/22; C07C2603/26
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
63 words
THE PROCESS FOR PREPARING 1-LOWER-ALKYL-2CARBO - LOWER - ALKOXY - 4 - KETO - 7 - OX 1,2,3,4-TETRAHYDROPHENANTHRENE WHICH COMPRISES TREATING IN THE COLD THE ACID HALIDE OF BETA(CARBO - LOWER - ALKOXY) - GAMMA -(6-XO-2NAPHTHYL)-GAMMA-LOWER-ALKYLBUTYRIC ACID WITH A FRIEDEL-CRAFTS TYPE OF CATALYST, WHERE X IS A HYDROCARBON GROUP SELECTED FROM THE CLASS CONSISTING OF LOWER ALKYL GROUPS AND BENZYL AND PHENYL GROUPS.
Claim 2
Dependent Claim
63 words
THE PROCESS FOR PREPARING 1-LOWER-ALKYL-2CARBO - LOWER - ALKOXY - 4 - KETO - 7 - OX 1,2,3,4-TETRAHYDROPHENANTHRENE WHICH COMPRISES TREATING IN THE COLD THE ACID HALIDE OF BETA(CARBO - LOWER - ALKOXY) - GAMMA -(6-XO-2NAPHTHYL)-GAMMA-LOWER-ALKYLBUTYRIC ACID WITH A FRIEDEL-CRAFTS TYPE OF CATALYST, WHERE X IS A HYDROCARBON GROUP SELECTED FROM THE CLASS CONSISTING OF LOWER ALKYL GROUPS AND BENZYL AND PHENYL GROUPS.
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) | 1956-11-09 | 1957-05-11 | 1957-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-11-09 | 1961-05-11 | 1961-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-11-09 | 1965-05-11 | 1965-11-10 | $7700.00 | Window Closed / Lapsed |