Synthesis of 1-aminoanthraquinone
AssigneeHoechst Celanese Corporation
InventorsMohammad Aslam, Daniel A. Aguilar
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Abstract
1-Aminoanthraquinone (1-AAQ) is synthesized by the condensation of 2-substituted benzoic acid and xylene to yield 2-substituted-dimethylbenzophenone, subsequent oxidation of the methyl groups, ring closure to form a 1-substituted anthraquinone carboxylic acid, replacement of the 1-substituent with ammonia, and decarboxylation.
Claims35
A process for producing a dimethylbenzophenone comprising condensing a 2-substituted benzoic acid with xylene in the presence of hydrogen fluoride.
A process for preparing 1-aminoanthraquinones from 2-substituted benzoic acid or a 2-substituted benzoic acid derivative and xylene which comprises the steps of (i) condensing 2-substituted benzoic acid or benzoic acid derivative with xylene in the presence of hydrogen fluoride for a period of time sufficient to obtain a 2-substituted dimethylbenzophenone;
- (ii) air oxidizing said 2-substituted dimethylbenzophenone in the presence of a cobalt-manganese-bromide catalyst for a period of time sufficient to obtain a 2-substituted benzophenone-dicarboxylic acid;
- (iii) contacting said benzophenonedicarboxylic acid with an acid for a period of time sufficient to obtain a 1-substituted anthraquinone-carboxylic acid;
- and (iv) contacting said anthraquinonecarboxylic acid with ammonia or an amine of the formula RNH.sub.2 wherein R is hydrogen, alkyl, cycloalkyl or aryl for a period of time sufficient to obtain a 1-amino-anthraquinonecarboxylic acid.
Dependencies are inferred from the claim text.