US2497739A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of separating isomers of amidone intermediates
Assignee: Merck and Co Inc
•
Filing: 1949-01-05
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Granted: 1950-02-14
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Expires: 1969-01-05
Abstract
No abstract record available.
Inventors
- 👤 Pfister Karl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 05:47
CPC Classifications
C; C07; C07C; C07C255/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
27 words
A PROCESS FOR THE SEPARATION OF A MIXTURE CONSISTING OF 2,2-DIPHENYL-4-DIMETHYLAMINOVALERONITRILE AND 2,2-DIPHENYL-3-METHYL-4-DIMETHYLAMINOBUTYRONITRILE WHICH COMPRISES PRECIPITATING SAID 2,2-DIPHENYL-3-METHYL-4-DIMETHYLAMINOBUTYRONITRILE FROM SAID MIXTURE BY THE ADDITION OF P-TOLUENESULFONIC ACID.
Claim 2
Dependent Claim
27 words
A PROCESS FOR THE SEPARATION OF A MIXTURE CONSISTING OF 2,2-DIPHENYL-4-DIMETHYLAMINOVALERONITRILE AND 2,2-DIPHENYL-3-METHYL-4-DIMETHYLAMINOBUTYRONITRILE WHICH COMPRISES PRECIPITATING SAID 2,2-DIPHENYL-3-METHYL-4-DIMETHYLAMINOBUTYRONITRILE FROM SAID MIXTURE BY THE ADDITION OF P-TOLUENESULFONIC ACID.
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) | 1953-02-13 | 1953-08-15 | 1954-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-02-13 | 1957-08-15 | 1958-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-02-13 | 1961-08-15 | 1962-02-14 | $7700.00 | Window Closed / Lapsed |