US2605263A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of piperazine
Assignee: Rohm and Haas Co
•
Filing: 1949-12-16
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Granted: 1952-07-29
•
Expires: 1969-12-16
Abstract
No abstract record available.
Inventors
- 👤 Martin J Culver
- 👤 Louis H Bock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:03
CPC Classifications
C; C07; C07D; C07D295/00; C07D295/02; C07D295/023
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
57 words
A PROCESS FOR PREPARING PIPERAZINE WHICH COMPRISES HYDROGENATING DI(CYANOMETHYL) AMINE UNDER PRESSURE IN THE PRESENCE OF AN ACID-TREATED ACTIVE METAL CATALYST FROM THE CLASS CONSISTING OF NICKEL AND COBALT, THE ACID USED FOR TREATING CATALYST BEING AN ORGANIC, WATER-SOLUBLE ACID COMPOSED OF ONLY CARBON, HYDROGEN, AND OXYGEN, AN AQUEOUS SUSPENSION OF SAID HAVING A PH BELOW 7.
Claim 2
Dependent Claim
57 words
A PROCESS FOR PREPARING PIPERAZINE WHICH COMPRISES HYDROGENATING DI(CYANOMETHYL) AMINE UNDER PRESSURE IN THE PRESENCE OF AN ACID-TREATED ACTIVE METAL CATALYST FROM THE CLASS CONSISTING OF NICKEL AND COBALT, THE ACID USED FOR TREATING CATALYST BEING AN ORGANIC, WATER-SOLUBLE ACID COMPOSED OF ONLY CARBON, HYDROGEN, AND OXYGEN, AN AQUEOUS SUSPENSION OF SAID HAVING A PH BELOW 7.
References Cited (Backward Citations)
US2267686A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-07-29 | 1956-01-28 | 1956-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-07-29 | 1960-01-28 | 1960-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-07-29 | 1964-01-28 | 1964-07-29 | $7700.00 | Window Closed / Lapsed |