Patent US3822287A successfully refreshed from Google Patents.
US3822287A
Expired / Lapsed
US
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Process for preparation of substituted 3,4-(diphenyl)chromans
Assignee: Dart Industries Inc
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Filing: 1972-06-08
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Granted: 1974-07-02
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Expires: 1992-06-08
Abstract
Abstract SUBSTITUTED 3,4-DIPHENYLCHROMANS IN TRANS CONFIGURATION ARE OBTAINED BY A PROCESS WHEREIN A 2M2-BIS(LOWER ALKYL)3 - PHENYL=4-(HYDROXYOHENYL)CHROMENE IS HYDROGENATED, PROVIDNG A CIS-2,2-BIS(LOWER ALKYL)-3-PHENYL-4-(HYDROXYPHENYL)CHROMAN WHICH IS REACTED WITH A PRIMARY, SECONDARY OR TERTIARY LOWER HALOALKYLAMINE TO FORM THE CORRESPONDING CIS-2,2-BIS(LOWER ALKYL)-3-PHENYL-4-(AMINO OR SUBSTITUTED AMINOALKOXYPHENYL)CHROMAN, FOLLOWED BY THE STEP OF TRANSFORMING THE CIS ISOMER TO THE TRANS CONFIGURATION BY MEANS OF A BASE-CATALYZED REARRANGEMENT.
Inventors
- 👤 J Bolger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:49
CPC Classifications
C; C07; C07D; C07D311/00; C07D311/02; C07D311/04; C07D311/58
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-01 | 1977-12-31 | 1978-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-01 | 1981-12-31 | 1982-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-01 | 1985-12-31 | 1986-07-02 | $7700.00 | Window Closed / Lapsed |