EP0044893A1
Expired / Lapsed
EP
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Anthraquinone compounds and process for their preparation
Assignee: Imperial Chemical Industries Ltd
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Filing: 1980-07-29
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Granted: —
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Expires: 2000-07-29
Abstract
Abstract Compounds of the formula: wherein R 1 is alkyl or aryl; X is H, NH 2 or NHCH 3 ; on of Y and Z is OH and the other is H, NH 2 or NHCH 3 ; and one of R 2 and R 3 is H and the one that is ortho to the OH group is a-CH 2 R 1 radical. The compounds include pleochroic dyes useful in liquid crystal display systems.
Inventors
- 👤 Andrew Hunter Morris Renfrew
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 17:46
CPC Classifications
C; C09; C09B; C09B1/00; C09B1/50; C09B1/51; C09B1/02; C09B1/06; C09K; C09K19/00; C09K19/52; C09K19/60; C09K19/603
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
69 words
An anthraquinone compound of the formula: wherein R 1 represents an alkyl or aryl radical; X is H, NH 2 or NHCH 3 ; one of Y and Z is OH and the other is H, NH 2 or NHCH 3 ; one and of R 2 and R 3 is H and the one that is ortho to the OH group is a -CH 2 R 1 radical.
Claim 2
Dependent Claim
69 words
An anthraquinone compound of the formula: wherein R 1 represents an alkyl or aryl radical; X is H, NH 2 or NHCH 3 ; one of Y and Z is OH and the other is H, NH 2 or NHCH 3 ; one and of R 2 and R 3 is H and the one that is ortho to the OH group is a -CH 2 R 1 radical.
Claim 3
Dependent Claim
41 words
An anthraquinone compound according to claim 1 having the formula: wherein R 1 is an alkyl radical containing from 2 to 9 carbon atoms and one of Y 2 and Z 2 is OH and the other is NH 2 .
Claim 4
Dependent Claim
10 words
An anthraquinone compound according to claim 2 having the formula:
Claim 5
Dependent Claim
10 words
An anthraquinone compound according to claim 2 having the formula:
Claim 6
Dependent Claim
73 words
A method for the preparation of an anthraquinone compound according to claim 1 having the formula: wherein R 1 , R 2 and R 3 have the meanings given in claim 1 and one of Y 1 and Z 1 is OH and the other is H which comprises reacting an anthraquinone compound of the formula: with an aldehyde of the formula R 1 CHO in the presence of aqueous alkaline sodium dithionite.
Claim 7
Dependent Claim
73 words
A method for the preparation of an anthraquinone compound according to claim 1 having the formula: wherein R 1 , R 2 and R 3 have the meanings given in claim 1 and one of Y 2 and Z 2 is OH and the other is NH 2 which comprises nitrating a compound of the formula: as defined in claim 5 to form the corresponding dinitro compound and then reducing the nitro groups.
References Cited (Backward Citations)
No citation records indexed.
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