Process for producing 1,4-diaminoanthraquinone-2-sulfonic acid
AssigneeSumitomo Chemical Company, Limited
InventorsMakoto Hattori, Akihiro Taguma, Akira Takeshita
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Abstract
A process for the production of 1,4-diaminoanthraquinone-2-sulfonic acid or a salt thereof is disclosed, comprising reacting 1-amino-4-bromoanthraquinone-2-sulfonic acid or its salt with liquid ammonia in the presence of a copper catalyst wherein the reaction is carried out in the presence of an inert organic solvent, e.g., n-heptane and cyclohexane. In this process, crystals of the desired product do not substantially deposit on reactor walls, and distillation recovery of ammonia can be performed easily without causing deterioration of the desired product. 1,4-Diaminoanthraquinone-2-sulfonic acid or salt thereof is a useful intermediate for the preparation of, e.g., anthraquinone dyes.
Claims6
A process for producing 1,4-diaminoanthraquinone-2-sulfonic acid or a salt thereof comprising reacting 1-amino-4-bromoanthraquinone-2-sulfonic acid or a salt thereof with liquid ammonia in the presence of a copper catalyst, wherein the reaction is carried out in the presence of an inert organic solvent selected from the group consisting of a paraffinic saturated hydrocarbon, a naphthenic saturated hydrocarbon, and a mixture thereof.
Dependencies are inferred from the claim text.