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US3947442A
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Method for producing heterocyclic acid anhydrides and pyrimidinediones
Assignee: PMC Inc
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Filing: 1975-02-10
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Granted: 1976-03-30
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Expires: 1995-02-10
Abstract
Abstract A method for producing heterocyclic acid anhydrides and pyrimidinediones from the corresponding acids, dicarboxamides, 2,3-and 3,4-pyridinedicarboxamides, and N-monosubstituted 2,3-and 3,4-pyridinedicarboxamides, in which the aforesaid compounds are reacted with lead tetra-acetate in the presence of a suitable anhydrous inert solvent.
Inventors
- 👤 Athelstan L. J. Beckwith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:59
CPC Classifications
C; C07; C07D; C07D239/00; C07D239/70; C07D239/72; C07D239/95; C07D239/96; C07D475/00; C07D475/02
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
130 words
A method for producing a pyrimidinedione having the formula, ##SPC4## wherein each of W, X, Y and Z is N or CH and, not more than two of W, X, Y and Z can be N, and R is hydrogen or an alkyl group having not more than 8 carbon atoms, said method comprising dissolving in an inert anhydrous solvent substantially equivalent amounts of lead tetraacetate and a compound having the formula ##SPC5## wherein each of W, X, Y and Z is N or CH and, not more than two of W, X, Y and Z can be N, and one R is hydrogen while the other R has the meaning set forth above, agitating the reaction mixture at a temperature sufficiently high that reaction occurs and recovering the pyrimidinedione.
Claim 2
Independent Claim
130 words
A method for producing a pyrimidinedione having the formula, ##SPC4## wherein each of W, X, Y and Z is N or CH and, not more than two of W, X, Y and Z can be N, and R is hydrogen or an alkyl group having not more than 8 carbon atoms, said method comprising dissolving in an inert anhydrous solvent substantially equivalent amounts of lead tetraacetate and a compound having the formula ##SPC5## wherein each of W, X, Y and Z is N or CH and, not more than two of W, X, Y and Z can be N, and one R is hydrogen while the other R has the meaning set forth above, agitating the reaction mixture at a temperature sufficiently high that reaction occurs and recovering the pyrimidinedione.
Claim 3
Dependent Claim
14 words
A method as claimed in claim 1 wherein the second named reactant is phthalamide.
Claim 4
Dependent Claim
14 words
A method as claimed in claim 1 wherein the second named reactant is pyridine-2,3-dicarboxamide.
Claim 5
Dependent Claim
14 words
A method as claimed in claim 1 wherein the second named reactant is pyrazine-2,3-dicarboxamide.
Claim 6
Dependent Claim
16 words
A method as claimed in claim 1 wherein the second named reactant is a N-monosubstituted 2,3-pyridinedicarboxamide.
References Cited (Backward Citations)
US3887550A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-03-30 | 1979-09-29 | 1980-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-30 | 1983-09-29 | 1984-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-30 | 1987-09-29 | 1988-03-30 | $7700.00 | Window Closed / Lapsed |