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US4347357A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the preparation of v-triazole compounds

Assignee: Bayer AG
•
Filing: 1981-04-30
•
Granted: 1982-08-31
•
Expires: 2001-04-30
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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 03:07
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

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