GB769183A - Improvements in the production of derivatives of 1.4-diaminoanthraquinone - Google Patents

Abstract

Anthraquinone derivatives of the formula <FORM:0769183/IV(b)/1> in which A and B represent hydroxylamino, nitroso, or nitro groups, X is hydrogen, alkyl, or hydroxyl, and Y is hydrogen, halogen, alkyl, hydroxyl, amino, or nitro, are made by treating anthraquinone - 1(N),2 - isoxazoles, of which the 4-position is unsubstituted, in acid medium, with nitrous acid, and, if necessary, with oxidizing agents also. C-Methyl-anthraquinone-1(N),2-isoxazole yields 1-hydroxylamino-4-nitroso - 2 - acetyl - anthraquinone on treatment with nitrosyl sulphuric acid in sulphuric acid, and either of these substances yields the 1,4-dinitro or 1,4-dinitroso body with nitric acid according to conditions, and a further nitro group may be introduced into the other benzene nucleus. The various anthraquinone-2-aldehydes and 2-caproyl derivatives within the above formula may be similarly prepared from anthraquinone - 1(N),2 - isoxazole and its C-hexyl derivative. The products may be reduced to the 1,4-diamino derivatives (see Group IV (c)).ALSO:Derivatives of 1.4 - diaminoanthraquinone containing an aldehyde, ketone (i.e. acyl) or carboxy group in 2 - position are obtained by reduction in acid medium of compounds of the formula:- <FORM:0769183/IV(b)/1> in which A and B represent hydroxylamino, nitroso, or nitro groups, X is hydrogen, alkyl, or hydroxy, and Y is hydrogen, halogen, alkyl, hydroxyl, amino, or nitro (see Group IV(b)). Reducing agents specified are iron in hydrochloric acid, copper in sulphuric acid, zinc in formic acid, stannous chloride in acetic acid, titanous chloride in acetic acid, sodium dithionite in acetic acid catalytically excited hydrogen in acetic acid. The products dye cellulose esters, nylon, polynitriles and polyurethanes by the dispersion method. In examples, (1) 1.4 - nitro - nitroso - anthraquinone - 2 - aldehyde is reduced to 1.4 - diaminoanthraqinone - 2 - aldehyde with copper and sulphuric acid; (2) 1.4 - dinitroso - 2 - acetylanthraquinone is similarly reduced, and (3) its 5 - nitro derivative is reduced with sodium dithionite in acetic acid; (4) 1.4 - dinitro - 2 - acetyl-anthraquinone is reduced with copper and sulphuric acid and the corresponding 2 - carboxy body with stannous chloride, or sodium hyposulphite, or zinc dust in acetic acid.