US4005146A
Expired / Lapsed
US
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Resolution of dl-allethrolone
Assignee: Sanofi Aventis France
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Filing: 1975-09-24
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Granted: 1977-01-25
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Expires: 1995-09-24
Abstract
Abstract A novel process for the resolution of dl-allethrolone or 2-allyl-4-hydroxy-3-methyl-2-cyclopentene-1-one whose chrysanthemic acid esters have insecticidal activity and to novel intermediates.
Inventors
- 👤 Bernard Goffinet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 16:42
CPC Classifications
C; C07; C07C; C07C49/00; C07C49/587; C07C49/703; C07C49/707
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
129 words
A process for the resolution of dl-allethrolone comprising reacting dl-allethrolone with an excess of succinic acid anhydride to form the hemisuccinate of dl-allethrolone, reacting the latter with ephedrine in an appropriate organic solvent selected from the group consisting of aromatic hydrocarbon, lower alkyl esters of lower alkanoic acids, lower aliphatic nitriles and lower aliphatic alcohols to form the ephedrine salt of the said hemisuccinate and crystallizing from the organic solvent a member selected from the group consisting of dextro ephedrine salt of the hemisuccinate of d-allethrolone and levo ephedrine salt of the hemisuccinate of l-allethrolone, reacting the recovered ephedrine salt with a dilute aqueous acid to form the resulting hemisuccinate and hydrolysing the latter by heating in an aqueous acid media to form the corresponding optical isomer of allethrolone.
Claim 2
Dependent Claim
129 words
A process for the resolution of dl-allethrolone comprising reacting dl-allethrolone with an excess of succinic acid anhydride to form the hemisuccinate of dl-allethrolone, reacting the latter with ephedrine in an appropriate organic solvent selected from the group consisting of aromatic hydrocarbon, lower alkyl esters of lower alkanoic acids, lower aliphatic nitriles and lower aliphatic alcohols to form the ephedrine salt of the said hemisuccinate and crystallizing from the organic solvent a member selected from the group consisting of dextro ephedrine salt of the hemisuccinate of d-allethrolone and levo ephedrine salt of the hemisuccinate of l-allethrolone, reacting the recovered ephedrine salt with a dilute aqueous acid to form the resulting hemisuccinate and hydrolysing the latter by heating in an aqueous acid media to form the corresponding optical isomer of allethrolone.
Claim 3
Dependent Claim
35 words
The method of claim 1 wherein the organic solvent is selected from the group consisting of ethyl acetate, acetonitrile, tert.-amyl alcohol, isopropanol, styrene, ethylbenzene, xylene, benzene and toluene and a mixture of benzene and toluene.
Claim 4
Dependent Claim
12 words
The method of claim 1 wherein the solvent is a benzene-toluene mixture.
Claim 5
Dependent Claim
11 words
The method of claim 1 wherein the solvent is ethyl acetate.
Claim 6
Dependent Claim
10 words
The method of claim 1 wherein the solvent is benzene.
Claim 7
Dependent Claim
10 words
The method of claim 1 wherein the solvent is isopropanol.
Claim 8
Dependent Claim
10 words
The method of claim 1 wherein the solvent is xylene.
Claim 9
Dependent Claim
11 words
The method of claim 1 wherein the solvent is tert.-amyl alcohol.
Claim 10
Dependent Claim
10 words
The method of claim 1 wherein the solvent is ethylbenzene.
Claim 11
Dependent Claim
10 words
The method of claim 1 wherein the solvent is styrene.
Claim 12
Dependent Claim
10 words
The method of claim 1 wherein the solvent is acetonitrile.
Claim 13
Dependent Claim
10 words
The method of claim 1 wherein the solvent is toluene.
Claim 14
Dependent Claim
26 words
The method of claim 1 wherein the dilute acid that reacts with the ephedrine salt of the hemisuccinate of optically active allethrolone is dilute oxalic acid.
Claim 15
Dependent Claim
26 words
The method of claim 1 wherein the dilute acid that reacts with the ephedrine salt of the hemisuccinate of optically active allethrolone is dilute hydrochloric acid.
Claim 16
Dependent Claim
24 words
The method of claim 1 wherein the acid in the presence of which the hemisuccinate of optically active allethrolone is heated, is sulfuric acid.
References Cited (Backward Citations)
US3484489A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-01-25 | 1980-07-26 | 1981-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-25 | 1984-07-26 | 1985-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-25 | 1988-07-26 | 1989-01-25 | $7700.00 | Window Closed / Lapsed |