Patent US3968099A successfully refreshed from Google Patents.
US3968099A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of azo dyestuffs containing cyano groups
Assignee: Bayer AG
•
Filing: 1975-01-17
•
Granted: 1976-07-06
•
Expires: 1995-01-17
Abstract
Abstract The invention relates to the preparation of ortho-cyano azo dyestuffs by conversion of azo dyestuffs of the formula ##EQU1## wherein A is an aromatic-carbocyclic radical, K is the radical of a component and X is a chlorine, bromine or iodine atom which is in the o-position to the azo group With CuCN or CuCN-forming compounds in polar organic sovents in the presence of azoles.
Inventors
- 👤 Klaus Leverenz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 23:00
CPC Classifications
C; C09; C09B; C09B43/00; C09B43/40; C09B43/42
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
123 words
Process for the preparation of an azo dyestuff which contains in the diazo component at least one cyano group in the orthoposition to the azo bridge, which comprises reacting an azo dyestuff of the general formula ##EQU4## wherein A is an aromatic-carbocyclic radical, K is the radical of a coupling component and X is a chlorine, bromine or iodine atom which is in the o-position to the azo group with CuCN or CuCN-forming compounds in polar organic solvents having a dielectric constant of >10 in the presence of an azole selected from the group consisting of imidazole, 1-methylimidazole, 2-methylimidazole, benzimidazole, 1-methylbenzimidazole, 2-methylbenzimidazole, 2-methylbenzthiazole, 4,5-dimethylthiazole, 2-methylbenzoxazole, and pyrazole, and recovering said azo dyestuff wherein the halogen substituent X is replaced by a cyano substituent.
Claim 2
Dependent Claim
123 words
Process for the preparation of an azo dyestuff which contains in the diazo component at least one cyano group in the orthoposition to the azo bridge, which comprises reacting an azo dyestuff of the general formula ##EQU4## wherein A is an aromatic-carbocyclic radical, K is the radical of a coupling component and X is a chlorine, bromine or iodine atom which is in the o-position to the azo group with CuCN or CuCN-forming compounds in polar organic solvents having a dielectric constant of >10 in the presence of an azole selected from the group consisting of imidazole, 1-methylimidazole, 2-methylimidazole, benzimidazole, 1-methylbenzimidazole, 2-methylbenzimidazole, 2-methylbenzthiazole, 4,5-dimethylthiazole, 2-methylbenzoxazole, and pyrazole, and recovering said azo dyestuff wherein the halogen substituent X is replaced by a cyano substituent.
Claim 3
Dependent Claim
17 words
Process according to claim 1 wherein the reaction is carried out at temperatures of 40° to 120°C.
Claim 4
Dependent Claim
13 words
Process according to claim 1 wherein the reaction is carried out in dimethylformamide/imidazole.
References Cited (Backward Citations)
GB1184825A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-07-06 | 1980-01-05 | 1980-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-06 | 1984-01-05 | 1984-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-06 | 1988-01-05 | 1988-07-06 | $7700.00 | Window Closed / Lapsed |