Patent US4439612A successfully refreshed from Google Patents.
Patent US3922286A successfully refreshed from Google Patents.
US3922286A
Expired / Lapsed
US
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Process for the production of optically active dihydrochrysanthemolactone
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1972-03-14
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Granted: 1975-11-25
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Expires: 1992-03-14
Abstract
Abstract Optically active dihydrochrysanthemolactone is obtained by means of optical resolution of ( + OR - )-dihydrochrysanthemolactone by adding as seed crystals optically active dihydrochrysanthemolactone to an organic solvent solution saturated or supersaturated with the racemic lactone, and is useful as an intermediate for the production of optically active chrysanthemic acid.
Inventors
- 👤 Hirosuke Yoshioka
- 👤 Akio Higo
- 👤 Hajime Hirai
- 👤 Nobushige Itaya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:26
CPC Classifications
C; C07; C07D; C07D311/00; C07D311/02; C07D311/94
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
92 words
A METHOD FOR PREPARING OPTICALLY ACTIVE DIHYDROCHRYSANTHEMOLACTONE, COMPRISING THE STEPS OF OPTICAL RESOLUTION OF ($)-DIHYDROCHRYSANTHEMOLACTONE BY ADDING AS SEED CRYSTALS OPTICALLY ACTIVE DIHYDROCHRYSANTHEMOLACTONE TO A SOLUTION AT A TEMPERATURE OF -30* TO 60*C OF AN ORGANIC SOLVENT SELECTED FROM THE GROUP CONSISTING OF PARAFFINIC HYDROCARBON, AROMATIC HYDROCARBON, MONOTERPENE HYDROCARBON, HALOGENATED HYDROCARBON, A POLAR SOLVENT MIXED WITH WATER AND MIXTURES THEREOF WHICH IS SATURATED OR SUPERSATURATED WITH ($)-DIHYDROCHRYSANTHEMOLACTONE, AND ALLOWING TO STAND THE RESULTING MIXTURE FOR 5 TO 50 HOURS AT A TEPERATURE OF -30* TO 60*C TO DEPOSIT THE OPTICALLY ACTIVE DIHYDROCHRYSANTHEMOLACTONE.
Claim 2
Independent Claim
92 words
A METHOD FOR PREPARING OPTICALLY ACTIVE DIHYDROCHRYSANTHEMOLACTONE, COMPRISING THE STEPS OF OPTICAL RESOLUTION OF ($)-DIHYDROCHRYSANTHEMOLACTONE BY ADDING AS SEED CRYSTALS OPTICALLY ACTIVE DIHYDROCHRYSANTHEMOLACTONE TO A SOLUTION AT A TEMPERATURE OF -30* TO 60*C OF AN ORGANIC SOLVENT SELECTED FROM THE GROUP CONSISTING OF PARAFFINIC HYDROCARBON, AROMATIC HYDROCARBON, MONOTERPENE HYDROCARBON, HALOGENATED HYDROCARBON, A POLAR SOLVENT MIXED WITH WATER AND MIXTURES THEREOF WHICH IS SATURATED OR SUPERSATURATED WITH ($)-DIHYDROCHRYSANTHEMOLACTONE, AND ALLOWING TO STAND THE RESULTING MIXTURE FOR 5 TO 50 HOURS AT A TEPERATURE OF -30* TO 60*C TO DEPOSIT THE OPTICALLY ACTIVE DIHYDROCHRYSANTHEMOLACTONE.
Claim 3
Dependent Claim
20 words
A method according to claim 2, wherein the paraffinic hydrocarbon is n-hexane, cyclohexane, petroleum ether, ligroin, or a mixture thereof.
Claim 4
Dependent Claim
18 words
A method according to claim 2, wherein the aromatic hydrocarbon is benzene, toluene, xylene or a mixture thereof.
Claim 5
Dependent Claim
21 words
A method according to claim 2, wherein the monoterpene hydrocarbon is Delta 3-carene, Alpha -pinene, Beta -pinene or a mixture thereof.
Claim 6
Dependent Claim
17 words
A method according to claim 2, wherein the halogenated hydrocarbon is tetrachloromethane, tetrachloroethane or a mixture thereof.
Claim 7
Dependent Claim
20 words
A method according to claim 2, wherein the polar solvent to be mixed with water is methanol, ethanol or acetone.
Claim 8
Dependent Claim
17 words
A method according to claim 1, wherein (+)- or (-)-dihydrochrysAnthemolactone is added to the organic solvent solution.
Claim 9
Dependent Claim
22 words
A method according to claim 1, wherein (+)- and (-)-dihydrochrysanthemolactones are simultaneously added to properly distanced zones of the organic solvent solution.
References Cited (Backward Citations)
US3529022A
Cited
US3732255A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |