GB473914A - Improvements in the manufacture and production of compounds of the anthraquinone series containing nitrogen and sulphur - Google Patents

Abstract

The vat dyes obtainable according to the process described in Specification 389,961, wherein 1.2<1>-dianthraquinonylsulphide or its oxidation products of the character of 1.2<1>-dianthraquinonylsulphoxide or their halogen substitution products are heated with zinc chloride, are first nitrated, and the resulting nitro compounds are reduced. The products are vat dyes or intermediates, and may be reacted with halogen compounds of simple or vattable polynuclear compounds, such as halogen anthraquinones or halogen benzanthrones, or they may be converted to quinoline compounds by a Skraup synthesis. In examples, the dye obtained in the example according to Specification 389,961 is nitrated with (1) nitric acid only, giving a dinitro compound which is reduced by alkaline sodium hydrosulphite to a diamino compound, (2) nitrating acid, giving a mononitro compound, which is reduced with sodium sulphide or phenyl hydrazine and aniline to a monoamino compound, which may be diazotized, (3) a current of nitrogen dioxide, the starting material being dispersed in nitrobenzene or trichlorbenzene, giving a mononitro body, or, if a little sulphuric acid is added to the nitrobenzene, a dinitro body, the nitro body being then reduced, or (4) nitric acid in nitrobenzene, giving a mononitro body, which is reduced with sodium sulphide. The monoamino compounds dye cotton moss-green shades, and the diamino grey-olive shades.