US4551552A
Expired / Lapsed
US
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Process for preparing rimantadine
Assignee: Bristol Myers Squibb Pharma Co
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Filing: 1984-05-23
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Granted: 1985-11-05
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Expires: 2004-05-23
Abstract
Abstract A low temperature and pressure process for preparing rimantadine in high yields from 1-adamantyl methyl ketoxime is provided. The process comprises contacting a solution of the ketoxime with hydrogen in the presence of a platinum on carbon catalyst at a low temperature and pressure, e.g., room temperature and a pressure of about 25-115 psia (170-790 KPa) are preferred.
Inventors
- 👤 John J. Liu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:54
CPC Classifications
C; C07; C07C; C07C209/00; C07C209/30; C07C209/40; C07C2603/00; C07C2603/56; C07C2603/58; C07C2603/70; C07C2603/74
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
60 words
In a process for the preparation of rimantadine by the reduction of 1-adamantyl methyl ketoxime, the improvement comprising reducing the ketoxime by contacting a solution of the ketoxime with hydrogen in the presence of a platinum on carbon catalyst at a temperature in the range of about 10°-60° C. and a pressure of about 25 to 215 psia (170-1500 KPa).
Claim 2
Dependent Claim
60 words
In a process for the preparation of rimantadine by the reduction of 1-adamantyl methyl ketoxime, the improvement comprising reducing the ketoxime by contacting a solution of the ketoxime with hydrogen in the presence of a platinum on carbon catalyst at a temperature in the range of about 10°-60° C. and a pressure of about 25 to 215 psia (170-1500 KPa).
Claim 3
Dependent Claim
35 words
The process of claim 1 wherein the temperature is in the range of about 10°-30° C. and the pressure is in the range of about 25 psia (170 KPa) to about 115 psia (790 KPa).
Claim 4
Dependent Claim
28 words
The process of claim 2 wherein the ketoxime solution is selected from the group of ketoxime dissolved in an acid and ketoxime dissolved in an acidified protic solvent.
Claim 5
Dependent Claim
19 words
The process of claim 3 wherein the acid is glacial acetic acid and the protic solvent is ethyl alcohol.
Claim 6
Dependent Claim
23 words
The process of claim 3 wherein the catalyst is about 4 to 6 percent by weight platinum deposited on particles of carbon black.
Claim 7
Dependent Claim
73 words
In a process for the preparation of rimantadine by the reduction of 1-adamantyl methyl ketoxime, the improvement comprising contacting in a pressurized reaction zone a solution of the ketoxime in acetic acid with hydrogen in the presence of a platinum on carbon catalyst at a temperature in the range of about 10°-30° C. and a pressure in the range of about 25-115 psia (170-790 KPa), and recovering rimantadine from the resulting reaction mixture.
Claim 8
Dependent Claim
73 words
In a process for the preparation of rimantadine by the reduction of 1-adamantyl methyl ketoxime, the improvement comprising contacting in a pressurized reaction zone a solution of the ketoxime in acetic acid with hydrogen in the presence of a platinum on carbon catalyst at a temperature in the range of about 10°-30° C. and a pressure in the range of about 25-115 psia (170-790 KPa), and recovering rimantadine from the resulting reaction mixture.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-11-04 | 1989-05-06 | 1989-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-11-04 | 1993-05-06 | 1993-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-11-04 | 1997-05-06 | 1997-11-05 | $7700.00 | Window Closed / Lapsed |