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US4347357A
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Process for the preparation of v-triazole compounds
Assignee: Bayer AG
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Filing: 1981-04-30
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Granted: 1982-08-31
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Expires: 2001-04-30
Abstract
Abstract Water-soluble 2-aryl-v-triazoles are obtained in a simple manner and in surprisingly good yields when corresponding α-oximinoarylhydrazones are heated to temperatures of 120°-200° C. in water or predominantly aqueous media in the absence of the cyclizing agents which are otherwise customary. The process products are valuable UV-absorbers or optical brighteners.
Inventors
- 👤 Alfons Dorlars
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:15
CPC Classifications
C; C07; C07D; C07D249/00; C07D249/02; C07D249/04; C07D249/06
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
57 words
In the cyclodehydration of an α-oximinohydrazone of the formula ##STR17## in which R 1 and R 2 each independently is an optionally substituted alkyl or aryl radical, and Ar is an arylene radical, to produce the corresponding 2-aryl-v-triazole, the improvement which consists essentially of effecting the cyclodehydration at 120° to 200° C. in a predominantly aqueous medium.
Claim 2
Dependent Claim
57 words
In the cyclodehydration of an α-oximinohydrazone of the formula ##STR17## in which R 1 and R 2 each independently is an optionally substituted alkyl or aryl radical, and Ar is an arylene radical, to produce the corresponding 2-aryl-v-triazole, the improvement which consists essentially of effecting the cyclodehydration at 120° to 200° C. in a predominantly aqueous medium.
Claim 3
Dependent Claim
16 words
The process according to claim 1, wherein the cyclodehydration is effected at 140° to 165° C.
References Cited (Backward Citations)
US3666758A
Cited
US3965094A
Cited
US3947412A
Cited
US4233440A
Cited
US4167626A
Cited
US4017509A
Cited
US4217449A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-08-30 | 1986-03-01 | 1986-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-08-30 | 1990-03-01 | 1990-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-08-30 | 1994-03-01 | 1994-08-31 | $7700.00 | Window Closed / Lapsed |