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Patent US4012406A successfully refreshed from Google Patents.
US4012406A
Expired / Lapsed
US
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Process for the preparation of diaryl carbonates
Assignee: Bayer AG
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Filing: 1975-09-30
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Granted: 1977-03-15
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Expires: 1995-09-30
Abstract
Abstract A process for the preparation of a diaryl carbonate by the reaction of an aromatic monohydroxy compound with phosgene under elimination of hydrogen chloride, wherein said reaction is carried out in the presence of a catalytic quantity of an aromatic heterocyclic basic nitrogen compound, or a salt thereof, or an adduct thereof formed under the reaction conditions.
Inventors
- 👤 Hans Josef Buysch
- 👤 Heinrich Krimm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:08
CPC Classifications
C; C07; C07C; C07C68/00; C07C68/02
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
71 words
A process for the preparation of a diaryl carbonate by the reaction of an aromatic monohydroxy compound with phosgene under elimination of hydrogen chloride, wherein said reaction is carried out in the presence of a catalytic quantity of an aromatic heterocyclic basic nitrogen compound selected from the group consisting of pyridine, quinoxaline, imidazole, benzimidazole, pyrazole, triazole and benztriazole, or a salt thereof, or an adduct thereof formed under the reaction conditions.
Claim 2
Dependent Claim
71 words
A process for the preparation of a diaryl carbonate by the reaction of an aromatic monohydroxy compound with phosgene under elimination of hydrogen chloride, wherein said reaction is carried out in the presence of a catalytic quantity of an aromatic heterocyclic basic nitrogen compound selected from the group consisting of pyridine, quinoxaline, imidazole, benzimidazole, pyrazole, triazole and benztriazole, or a salt thereof, or an adduct thereof formed under the reaction conditions.
Claim 3
Dependent Claim
22 words
A process as claimed in claim 1, wherein the reaction is carried out at a temperature of from 25° to 200° C.
Claim 4
Dependent Claim
20 words
A process as claimed in claim 1, wherein 2 mols of aromatic monohydroxy compound are used per mol of phosgene.
Claim 5
Dependent Claim
19 words
A process as claimed in claim 1, wherein the aromatic monohydroxy compound contains from 6 to 16 carbon atoms.
Claim 6
Dependent Claim
59 words
A process as claimed in claim 4, wherein the aromatic monohydroxy compound is phenol, 0-, m- or p-cresol, o-, m- or p-isopropyl phenol, which phenols may be substituted by halogen or alkoxy; a monohydroxy compound of naphthalene, anthracene, phenanthrene or a heterocyclic radical with 5 to 6 ring members which may be condensed or substituted with a carbocyclic radical.
Claim 7
Dependent Claim
31 words
A process as claimed in claim 1, wherein the aromatic heterocyclic basic nitrogen compound is used is a quantity of from 0.1 to 10% by weight, based on the reaction mixture.
Claim 8
Dependent Claim
31 words
A process as claimed in claim 6, wherein the aromatic heterocyclic basic nitrogen compound is used in a quantity of from 1 to 3% by weight, based on the reaction mixture.
Claim 9
Dependent Claim
19 words
A process as claimed in claim 1, wherein the reaction is carried out in the presence of a solvent.
Claim 10
Dependent Claim
29 words
A process as claimed in claim 8, wherein the solvent is an aromatic hydrocarbon containing 6 to 16 carbon atoms, which may be halogenated or an aliphatic halogenated hydrocarbon.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-14 | 1980-09-13 | 1981-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-14 | 1984-09-13 | 1985-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-14 | 1988-09-13 | 1989-03-15 | $7700.00 | Window Closed / Lapsed |