US3920697A
Expired / Lapsed
US
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Method for preparing n-substituted nitrophthalimides
Assignee: General Electric Co
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Filing: 1973-06-22
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Granted: 1975-11-18
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Expires: 1993-06-22
Abstract
Abstract Bis(nitrophthalimide)s can be prepared by effecting reaction in a phenolic solvent between an organic diamine and a nitrosubstituted phthalimide or a nitro-substituted phthalic acid. The bis(nitrophthalimide)s can be employed as intermediates for making polyetherimides by a nitro displacement reaction with a diphenoxide.
Inventors
- 👤 Tohru Takekoshi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:43
CPC Classifications
C; C07; C07D; C07D209/00; C07D209/02; C07D209/44; C07D209/48
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
9 words
A METHOD FOR MAKING A BIS(NITROPHTHALIMIDE) OF THE FORMULA
Claim 2
Independent Claim
9 words
A METHOD FOR MAKING A BIS(NITROPHTHALIMIDE) OF THE FORMULA
Claim 3
Dependent Claim
14 words
A method in accordance with claim 1 where the nitrophthalic compound is 3-nitrophthalic anhydride.
Claim 4
Dependent Claim
14 words
A method in accordance with claim 1 where the nitrophthalic compound is 4-nitrophthalic anhydride.
Claim 5
Dependent Claim
14 words
A method in accordance with claim 1 where the nitrophthalic compound is 3-nitrophthalic acid.
Claim 6
Dependent Claim
14 words
A method in accordance with claim 1 where the nitrophthalic compound is 4-nitrOphthalic acid.
Claim 7
Dependent Claim
13 words
A method in accordance with claim 1 where the organic amine is methylenedianiline.
Claim 8
Dependent Claim
13 words
A method in accordance with claim 1 where the organic amine is oxydianiline.
Claim 9
Dependent Claim
19 words
A method in accordance with claim 1, where the nitrophthalic compound is a mixture of 3- and 4-nitrophthalic compounds.
References Cited (Backward Citations)
US3712907A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-17 | 1979-05-19 | 1979-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-17 | 1983-05-19 | 1983-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-17 | 1987-05-19 | 1987-11-18 | $7700.00 | Window Closed / Lapsed |