Patent US3828023A successfully refreshed from Google Patents.
US3828023A
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US
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Process for preparing cyclic oligomers of n-substituted aziridines
Assignee: Dow Chemical Co
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Filing: 1971-09-13
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Granted: 1974-08-06
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Expires: 1991-09-13
Abstract
Abstract CYCLIC OLIGOMERS OF N-ALKYLAZIRIDINES AND N-ARALKYLAZIRIDINES ARE PREPARED BY CONTACTING THE N-SUBSTITUTED AZIRIDINE MONOMER WITH AN ALKYLALUMINUM CATALYST AT A TEMPERATURE SUFFICIENT TO CAUSE REACTION. FOR EXAMPLE, THE CYCLIC TETRAMER OF N-ETHYLAZIRIDINE WAS PREPARED IN HIGH YIELDS BY CONTACTING N-ETHYLAZIRIDINE WITH TRIISOBUTYLALUMINUM AT 140*-150*C. FOR 20 HOURS UNDER AUTOGENOUS PRESSURE.
Inventors
- 👤 S Cornier
- 👤 C Wymore
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:42
CPC Classifications
C; C07; C07D; C07D203/00; C07D203/04; C07D203/06; C07D203/08
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) | 1977-08-05 | 1978-02-04 | 1978-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-05 | 1982-02-04 | 1982-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-05 | 1986-02-04 | 1986-08-06 | $7700.00 | Window Closed / Lapsed |