Syntheses of vat dyes containing carbazole ring were made by condensation 2, 3-dichloro-and 5-nitro-2, 3-dichloro-1, 4-naphthoquinone with aromatic primary amine by dehydrochlorination, substitution of the ortho position of imino group with bromine, then dehalogenation and cyclization with the use of activated copper. The aromatic primary amines used for formation of carbazole ring were
p-toluidine, β-naphthylamine, benzidine, o-dianisidine, and 1, 5-dimainoanthraquinone. Since the condensation of 1, 5-diaminoanthraquinone and dichloro naphthoquinone was difficult, 1, 4-additive reaction of the naphthoquinone was applied.
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