Process for the preparation of 1,4-diaminoanthraquinone-2,3-disulphonic acid

Abstract

1,4-Diaminoanthraquinone-2,3-disulphonic acid, which is a valuable dyestuff intermediate product, is obtained in a simple manner when 1,4-diamino-2,3-dichloroanthraquinone is reacted by itself with boric acid, that is to say without the condensation agents which are otherwise customary, such as phenol, sulphuric acid or acetic anhydride, and the reaction product is treated with alkali metal sulphites in a known manner. The new process is more economical and pollutes the environment to a lesser extent than the processes known hitherto.

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