Preparation of 1-amino-4-hydroxyanthraquinone
AssigneeBASF SE
InventorsErwin Hahn, Manfred Patsch, Heike Kilburg
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Abstract
A process for preparing 1-amino-4-hydroxyanthraquinone by treating 1,4-dihydroxyanthraquinone with ammonia in an aqueous medium comprises treating with ammonia in the presence of a base and of a catalytic amount of a reducing agent at from 60.degree. to 150.degree. C. and at from 1 to 30 bar.
Claims5
A process for preparing 1-amino-4-hydroxyanthraquinone which comprises heating an aqueous mixture consisting essentially of water, 1,4-dihydroxyanthraquinone, ammonia, a base and a catalytis amount of reducing agent selected from the group consisting of alkali metal dithionites, alkali metal sulfites, hydroxyacetone and thiourea S,S,-dioxide to a temperature of 60.degree. to 150.degree. C. at a pressure of 1 to 30 bar.
Dependencies are inferred from the claim text.