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US4623732A
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Process for the preparation of N-alkylphthalimide and copolymer derived therefrom
Assignee: General Electric Co
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Filing: 1983-11-18
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Granted: 1986-11-18
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Expires: 2003-11-18
Abstract
Abstract Compounds which are bis-(N-alkylphthalimides) are prepared by a new process in which a halogen-containing precursor is heated in the presence of a nickel compound, a reducing agent, for example, metallic zinc, and an organic solvent. The resulting compound is useful in a process for the preparation of a copolymer, in which the compound is reacted with alkali to form a tetraacid, the acid is dehydrated to form a dianhydride, and the dianhydride is reacted with a second dianhydride and a diamine under copolymer-forming conditions.
Inventors
- 👤 Edward N. Peters
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:34
CPC Classifications
C; C07; C07D; C07D209/00; C07D209/02; C07D209/44; C07D209/48; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1046; C08G73/1053; C08G73/1067; C08G73/1071
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
24 words
A compound of the formula: ##STR10## wherein R is lower alkyl of from 1 to 6 carbons and X is Cl, Br or I.
Claim 2
Dependent Claim
24 words
A compound of the formula: ##STR10## wherein R is lower alkyl of from 1 to 6 carbons and X is Cl, Br or I.
Claim 3
Dependent Claim
11 words
A compound as defined in claim 1 wherein R is methyl.
Claim 4
Dependent Claim
11 words
A compound as defined in claim 2 wherein X is Cl.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-17 | 1990-05-19 | 1990-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-17 | 1994-05-19 | 1994-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-17 | 1998-05-19 | 1998-11-18 | $7700.00 | Window Closed / Lapsed |