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US3678042A
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US
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Process for the manufacture of aryloxazoles
Assignee: BASF Schweiz AG
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Filing: 1969-09-30
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Granted: 1972-07-18
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Expires: 1989-09-30
Abstract
Abstract The invention provides a new process for preparation of aryloxazoles by ring closure reaction between an o-hydroxy-amino benzene and a carboxylic acid. The improvement over known processes consists in performing the reaction in a two-step heating procedure and in the presence of small amounts of specific amines, preferably non-aromatic cyclic nitrogen bases, having a Pk-value of at least 7. The reaction products are valuable optical whitening agents.
Inventors
- 👤 Erich Matter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:13
CPC Classifications
C; C07; C07D; C07D263/00; C07D263/52; C07D263/54; C07D263/56; C07D263/57; C07D263/62; C07D263/64
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
24 words
Process according to claim 1 wherein in that the reaction is carried out in the presence of a secondary or tertiary piperidine or piperazine.
Claim 2
Dependent Claim
109 words
Process according to claim 1 wherein, as the carboxylic acid component, a carboxylic acid, containing one to two carboxyl groups, of benzene, diphenyl, naphthalene, stilbene, styrene, thiophene or furane, or the analogues of these carboxylic acids containing one to three alkyl groups with one to four carbon atoms each, or an aliphatic dicarboxylic acid containing four carbon atoms, is reacted in approximately equivalent amount with an o-hydroxyaminophenol which can optionally be substituted by one to three alkyl groups with one to 18 carbon atoms, an alkoxy group with one to four carbon atoms, a carbalkoxy group with one to 12 carbon atoms, a halogen atom or a phenyl group.
Claim 3
Dependent Claim
48 words
Process according to claim 1, wherein a dicarboxylic acid of benzene, diphenyl, naphthalene, stilbene, thiophene or furane is reacted in approximately equivalent amount with a o-hydroxyaminobenzene which can optionally be substituted by one to three alkyl groups with one to four carbon atoms or by a phenyl group.
Claim 4
Dependent Claim
31 words
Process according to claim 1, wherein in that an o-hydroxyamino benzene of formula wherein n denotes an integer having a value of at most 5, is used as the hydroxyaminoaryl compound.
Claim 5
Dependent Claim
17 words
Process according to claim 1 wherein the condensation is carried out in a trichlorobenzene, diphenyl-ether or diphenyl.
Claim 6
Dependent Claim
38 words
Process according to claim 1, wherein the condensation is carried out in the presence of 0.5 to 10 percent by weight of boric acid calculated relative to the sum of the amount by weight of the condensation components.
Claim 7
Dependent Claim
35 words
Process according to claim 1 wherein the reaction is effected by heating in a first stage to temperatures of 150* to 200* C and in a second stage to temperatures of 200* to 260* C.
Claim 8
Dependent Claim
17 words
Process according to claim 1 wherein the reaction is carried out in the presence of an amylphenol.
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) | 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 |