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Patent US4294769A successfully refreshed from Google Patents.
US4294769A
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Process for the preparation of 1,4-diamino-2,3-dicyano-anthraquinones
Assignee: Bayer AG
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Filing: 1980-07-24
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Granted: 1981-10-13
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Expires: 2000-07-24
Abstract
Abstract 2,3-Dicyano-anthraquinones of the formula ##STR1## wherein R denotes hydrogen, alkyl or cycloalkyl, are obtained in good yields and high purity by reacting compounds of the formula ##STR2## wherein X denoted hydrogen or the sulphonic acid group, with cyanides in formamide or N-methylformamide as solvents, and if appropriate oxidizing agents and heavy metal catalysts.
Inventors
- 👤 Friedrich W. Krock
- 👤 Rutger Neeff
- 👤 Heinz Scheiter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:24
CPC Classifications
C; C09; C09B; C09B1/00; C09B1/16; C09B1/20; C09B1/26; C09B1/28; C09B1/22
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
65 words
Process for the preparation of 2,3-dicyanoanthraquinones of the formula ##STR9## wherein R denotes hydrogen, optionally substituted alkyl or optionally substituted cycloalkyl, by reacting sulphonic acids of the formula ##STR10## or salts thereof, wherein R has the abovementioned meaning and X denotes hydrogen or the sulphonic acid group, with compounds which donate cyanide ions, characterised in that the reaction is carried out in formamide or N-methyl-formamide.
Claim 2
Dependent Claim
65 words
Process for the preparation of 2,3-dicyanoanthraquinones of the formula ##STR9## wherein R denotes hydrogen, optionally substituted alkyl or optionally substituted cycloalkyl, by reacting sulphonic acids of the formula ##STR10## or salts thereof, wherein R has the abovementioned meaning and X denotes hydrogen or the sulphonic acid group, with compounds which donate cyanide ions, characterised in that the reaction is carried out in formamide or N-methyl-formamide.
Claim 3
Dependent Claim
15 words
Process according to claim 1, characterised in that the reaction is carried out in formamide.
Claim 4
Dependent Claim
28 words
Process according to claim 1, characterised in that the reaction is carried out in the presence of oxidising agents and if appropriate heavy metal catalysts and acid-binding agents.
Claim 5
Dependent Claim
23 words
Process according to claim 3, characterised in that air, oxygen, nitrobenzene or m-nitrobenzenesulphonic acid or salts thereof is used as the oxidising agent.
Claim 6
Dependent Claim
29 words
Process according to claim 3, characterised in that air, in the presence of heavy metal catalysts, such as vanadates, molybdates or copper salts, is used as the oxidising agent.
Claim 7
Dependent Claim
22 words
Process according to claim 1, characterised in that sodium cyanide or potassium cyanide is used as the compound which donates cyanide ions.
Claim 8
Dependent Claim
22 words
Process according to claim 1, characterised in that 1-amino-4-alkylamino-, 1-amino-4-cycloalkylamino- or 1,4-diamino-anthraquinone-2-sulphonic acids or salts thereof are employed as the sulphonic acids.
Claim 9
Dependent Claim
20 words
Process according to claim 1, characterised in that 1,4-diamino-anthraquinone-2-sulphonic acid or a salt thereof is employed as the sulphonic acid.
Claim 10
Dependent Claim
20 words
Process according to claim 1, characterised in that 1,4-diamino-anthraquinone-2,3-disulphonic acid or a salt thereof is employed as the sulphonic acid.
Claim 11
Dependent Claim
17 words
Dicyano-anthraquinone dyestuffs of the formula given in claim 1, wherein R denotes an optionally substituted cycloalkyl radical.
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) | 1984-10-12 | 1985-04-13 | 1985-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-12 | 1989-04-13 | 1989-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-12 | 1993-04-13 | 1993-10-13 | $7700.00 | Window Closed / Lapsed |