GB704013A - Manufacture of vat dyestuffs of the anthraquinone series - Google Patents

Abstract

The invention comprises anthrinide carbazoles of the formula: <FORM:0704013/IV (c)/1> in which R represents an anthraquinone nucleus bound in a -position to the NH group and in vicinal b -position directly to carbon atom X, and which contains an acylamino substituent in another a -position, and in which the benzene ring of the latter anthraquinone residue not condensed with the hetero ring may contain up to two halogen atoms in b -positions and in all at most two substituents. They are made by carbazolyzing the corresponding anthrimides, e.g. with sulphuric acid. In examples, the following are carbazolized with sulphuric acid, followed by treatment with nitrite: (1) 6.7-dichloro-4.5\sv-dibenzoylamino-1-1\sv-dianthrimide, (2) 6.7-dichloro-4.4\sv-dibenzoylamino-1 : 1\sv-dianthrimide, (3) 6.7, 6\sv.7\sv-tetrachloro-4.4\sv-dibenzoylamino-1.1\sv-dianthrimide. The products dye cotton, linen, artificial silk or regenerated cellulose brown shades. Other acyl radicals specified are acetyl and pyridine-3-carboyl. Other carbazolyzing agents are aluminium chloride, together with nitrobenzene, pyridine, or sulphur dioxide. A dyeing example is given, using the product of (1) to dye cotton. 1-Amino-6.7-dichloranthaquinone is obtained by nitration and reduction from 2.3-dichlor-anthraquinone. 1-Amino-4.6.7-trichloranthraquinone is obtained by chlorination and hydrolysis from 6.7-dichloranthraquinone-1-urethane, which is obtained from 1-amino-6.7-dichloroanthraquinone and chlorcarbonic ester. The dibenzoylamino-di- and tetra-chlor-dianthrimides used as starting materials above are prepared by condensing 1-benzoylamino-4.6.7-trichloranthraquinone with 1-amino-4 or 5- benzoylamino-anthraquinone or 1-benzoylamino-4-amino-6.7-dichloranthraquinone, obtained from 1-amino-6.7-dichloranthraquinone by nitration, benzoylation, and reduction.