Patent US3678102A successfully refreshed from Google Patents.
US3678102A
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{60 ,{60 ,{60 {40 ,{60 {40 -tetrasubstituted carboxylic diacids and process for their preparation
Assignee: Pechiney SA
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Filing: 1970-09-11
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Granted: 1972-07-18
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Expires: 1990-09-11
Abstract
Abstract And a process for preparing diacid (I) by reacting in an anhydrous medium a diester of the general formula: WITH A Grignard reagent R''''MgX or with an alkaline metal hydride, amide or alcoholate and then neutralizing and separating. Diacid II being prepared by reduction of diacid (I) such as by catalytic hydrogenation. An Alpha , Alpha , Alpha '' , Alpha ''-tetrasubstituted gamma methylene (and gamma -methyl) pimelic acid of the general formulas:
Inventors
- 👤 Arsene Isard
- 👤 Francis Weiss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:30
CPC Classifications
C; C07; C07C; C07C57/00; C07C57/30; C07C57/42; C07C51/00; C07C51/347; C07C51/36; C07C57/02; C07C57/13
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
43 words
Alpha , Alpha , Alpha '', Alpha '',-tetrasubstituted carboxylic diacid having the formula in which R and R'' represent a member selected from the group consisting of a lower alkyl having from one to four carbon atoms, phenylmethyl, phenylethyl, phenyl, p-chlorophenyl and p-methoxyphenyl.
Claim 2
Dependent Claim
31 words
Alpha , Alpha , Alpha '', Alpha '',-tetrasubstituted carboxylic diacid having the formula in which R and R'' form a divalent radical containing from two to 11 carbon atoms from alkylene.
Claim 3
Dependent Claim
13 words
The diacid as set forth in claim 3 wherein said alkylene is cyclohexene.
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) | 1975-07-18 | 1976-01-17 | 1976-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-18 | 1980-01-17 | 1980-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-18 | 1984-01-17 | 1984-07-18 | $7700.00 | Window Closed / Lapsed |