US3657308A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Catalytic carbonylation of aromatic nitro compounds in the presence of organic carbonates
Assignee: Olin Corp
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Filing: 1969-04-16
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Granted: 1972-04-18
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Expires: 1989-04-16
Abstract
Abstract IN THE PROCESS FOR PREPARING AN ORGANIC ISOCYANATE BY REACTING AN ORGANIC NITRO COMPOUND WITH CARBON MONOXIDE IN THE PRESENCE OF A CATALYST, IMPROVED YIELDS OF THE ORGANIC ISOCYANATE ARE OBTAINED AND CONTAMINATION OF THE ISOCYANATE BY PRODUCTS DERIVED FROM ORTHO-DINITRO COMPOUNDS IS SUPRESSED WHEN THE REACTION IS CARRIED OUT IN THE PRESENCE OF AN ORGANIC CARBONATE. IN ADDITION, WHEN THE CATALYST IS A NOBLE METAL HALIDE COMPLEX OF LEWIS BASE SUCH AS PYRIDINE OR ISOQUINOLINE, DECOMPOSITION OF THE CATALYST COMPLEX IS DIMINISHED.
Inventors
- 👤 Ehrenfried H Kober
- 👤 Wilhelm J Schnabel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:38
CPC Classifications
C; C07; C07C; C07C263/00; C07C263/14
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) | 1975-04-18 | 1975-10-18 | 1976-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-18 | 1979-10-18 | 1980-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-18 | 1983-10-18 | 1984-04-18 | $7700.00 | Window Closed / Lapsed |