US3919237A
Expired / Lapsed
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Preparation of isomorphinan derivative
Assignee: F Hoffmann La Roche AG
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Filing: 1973-07-03
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Granted: 1975-11-11
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Expires: 1993-07-03
Abstract
Abstract A process for preparing N-substituted isomorphinans via the acid catalyzed cyclization of the appropriately substituted isoquinoline, bearing in the 2-position an electron withdrawing group, utilizing as the cyclization catalyst a mixture of boron trifluoride and a proton/hydronium ion donor, is described. The isomorphinan products so produced are known compounds, useful as analgesic agents.
Inventors
- 👤 Niklaus Halder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:39
CPC Classifications
C; C07; C07D; C07D221/00; C07D221/02; C07D221/22; C07D221/28
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
9 words
A PROCESS FOR PREPARING AN ISOMORPHINAN OF THE FORMULA
Claim 2
Dependent Claim
9 words
A PROCESS FOR PREPARING AN ISOMORPHINAN OF THE FORMULA
Claim 3
Dependent Claim
23 words
The process of claim 1 wherein the R1 substituent is a lower alkyl group and the R2'' substituent is a lower alkanoyl group.
Claim 4
Dependent Claim
19 words
The process of claim 2 wherein the lower alkyl group is methyl and the lower alkanoyl group is formyl.
Claim 5
Dependent Claim
50 words
The process of claim 1 wherein the proton donor employed is selected from the group consisting of a mineral acid selected from the group consisting of ortho-phosphoric acid and pyrophosphoric acid, a C1 to C4 alkane carboxylic acid, a C1 to C4 lower alkanol and a C1 to C4 nitroalkane.
Claim 6
Dependent Claim
12 words
The process of claim 4 wherein the mineral acid is orthophosphoric acid.
Claim 7
Dependent Claim
14 words
The process of claim 4 wherein the alkane carboxylic acid used is acetic acid.
Claim 8
Dependent Claim
12 words
The process of claim 4 wherein the lower alkanol employed is methanol.
Claim 9
Dependent Claim
11 words
The process of claim 4 wherein the nitroalkane employed is nitromethane.
Claim 10
Dependent Claim
14 words
The process of claim 1 wherein water is used as the proton/hydronium ion donor.
Claim 11
Dependent Claim
21 words
The process of claim 1 wherein a mixture of a hydrogen halide and water is used at the proton/hydronium ion donor.
Claim 12
Dependent Claim
14 words
The process of claim 10 wherein hydrogen fluoride is used as the hydrogen halide.
References Cited (Backward Citations)
US3634429A
Cited
US3786054A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-10 | 1979-05-12 | 1979-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-10 | 1983-05-12 | 1983-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-10 | 1987-05-12 | 1987-11-11 | $7700.00 | Window Closed / Lapsed |