GB408456A - Manufacture of dyestuffs and intermediate products - Google Patents

Abstract

Oxazine dyes or intermediate products are prepared by condensing a 1.4-quinone compound of the benzene or naphthalene series with a monamino compound of pyrene, fluoranthene or chrysene or a halogen substitution product thereof containing a free o-position to the amino group, if desired in the presence of an oxidising agent, a metal chloride or an acylating agent. By working at a temperature below about 150 DEG C. intermediate products suitable for oxazine or sulphur dyes are obtained; by working at temperatures above about 150 DEG C. or so heating these intermediates advantageously in presence of an oxidising agent, a metal chloride or an acylating agent, oxazines are obtained which may be used as pigment dyes or sulphonated to yield dyes for animal or vegetable fibres or for viscose artificial silk. It is also possible to obtain the water-soluble dye sulphonates by treatment of the above intermediates with strong sulphuric acid, advantageously in presence of an oxidising agent, or by condensation or oxidation of such of these intermediates as contain sulpho groups. The dyestuff sulphonic acids in the form of their barium, calcium, or other suitable salts may be used as pigments. In examples: (1) 4-amino-fluoranthene is boiled with chloranil in alcohol; the intermediate obtained is boiled in nitrobenzene in presence of p-toluene sulphonic acid chloride to give a product which on sulphonation with monohydrate dyes animal, vegetable, and viscose artificial silk fibres in red-violet shades; chloranil may be replaced by toluquinone to give a similar dye sulphonic acid, and another intermediate may be obtained using a -naphtho quinone for the condensation; instead of 4 - aminofluoranthene 11 - aminofluoranthene (reduction of 11-nitro body which is a by-product in nitration) or aminochlorofluoranthene (chlorinate nitrofluoranthene and reduce) may be used to yield on sulphonation violet pigments: (2) 3-aminopyrene is boiled in alcohol with chloranil to give an intermediate product; this is boiled in nitrobenzene in presence of dinitrophenol to give a product which in dispersed form may be used for colouring paper or for printing purposes or as a lake dyestuff; on sulphonation with fuming sulphuric acid a greenish blue dye is obtained and this in the form of its barium or calcium salt is also of use as above; chloranil may be replaced by benzo-or a -naphthoquinone to give intermediate products, while 4-aminopyrene or an aminohalogenpyrene (prepared by chlorination of nitropyrene with subsequent reduction) may be similarly condensed with chloranil to give violet and blue dyes respectively; (3) aminochrysene is boiled in alcohol with chloranil; the product is boiled in nitrobenzene alone or in presence of ferric chloride and then sulphonated to give a greenish-blue dye; this product is also obtained by heating the intermediate in concentrated sulphuric acid, or the dye itself is obtained by boiling the above reactants in trichlorbenzene; if aminochrysene is replaced by aminobromochrysene (prepared by bromination of nitro body with subsequent reduction) a dye sulphonate dyeing blue shades is obtained. Specification 8886/12, [Class 2 (iii)], is referred to.