Patent GB-397693-A (GB)
Title: Manufacture of mono-azo-dyestuffs
Filed: 1932-10-17
Abstract: Monoazo dyes are obtained by coupling a diazotized amine of the general formula--  <FORM:0397693/IV/1> in which R represents an aromatic residue and X1 and X2 represent hydrogen or the same or different aliphatic, araliphatic or aromatic residues, with an aryl-sulphon (N)- or a benzoyl (N)- derivative of a 1 : 8-aminonaphtholdisulphonic acid. The products give red dyeings of good fastness to fulling and light on wool and silk, the dyeings on wool being particularly fast to sea water and those on silk to water. In an example, the preparation of the dyestuff, 2-aminodiphenylether-4-sulphonic acid --N-ethylanilide --> p-toluenesulpho (N)-1-amino-8-naphthol-3 : 6-disulphonic acid, is described.  The diazo component may be replaced by the corresponding sulphonamide, sulphonanilide or sulphon-o-toluidide of 2-aminodiphenylether or by 2-amino-2<1>-methyldiphenylether-4-sulphonanilide, and the coupling component by benzenesulphon (N)-1-amino-8-naphthol-3 : 6 or -4 : 6-disulphonic acid, p-toluenesulphon (N)-1-amino-8-naphthol-4 : 6-disulphonic acid or a 1-benzoylamino-8-naphtholdisulphonic acid. Specifications 17105/10, 337,577, [both in Class 2 (iii), Dyes &c.], and 364,609 are referred to.  Samples have been furnished under Sec. 2 (5) of the Acts of the dyestuffs from the following diazo components and p-toluenesulphon (N)-1 : 8-aminonaphthol-3 : 6-disulphonic acid: (1) 2-amino-4<1>-chlorodiphenylether-4-sulphonic acid-N-ethylanilide; (2) 2-aminodiphenylether-4-sulphonic acid-N-methylbenzylamide; (3) 2-aminodiphenylether-4-sulphonic acid-N-benzylanilide.  2-Aminodiphenylether-4-sulphonic acid-amide, anilide, o-toluidide and N-ethylanilide are obtained by reducing the nitro group of the condensation products from sodium phenolate and the 2-nitrochlorobenzene-4-sulphonic acid amide, anilide, o-toluidide and N-ethylanilide obtainable by treating 2-nitrochlorobenzene-4-sulphochloride with ammonia, aniline, o-toluidine and monoethylaniline respectively. 2-Amino-2<1>-methyldiphenylether-4-sulphonanilide is obtained by reducing the nitro group of the condensation product from sodium o-cresolate and the 2-nitrochlorobenzene-4-sulphonanilide obtainable by treating 2-nitrochlorobenzene-4-sulphochloride with aniline. 2-Amino-4<1>-chlorodiphenylether-4-sulphonic acid-N-ethylanilide is obtained by reducing the nitro group of the condensation product from sodium 4-chlorophenolate and the 2-nitrochlorobenzene-4-sulphonic acid-N-ethylanilide obtainable by treating 2-nitrochlorobenzene-4-sulphochloride with monoethylaniline. 2-Aminodiphenylether-4-sulphonic acid-N-methylbenzylamide is obtained by reducing the nitro group of the condensation product from sodium phenolate and the 2-nitrochlorobenzene-4-sulphonic acid-N-methylbenzylamide obtainable by treating 2-nitrochlorobenzene-4-sulphochloride with monomethylamine and benzyl chloride.  2-Aminodiphenylether-4-sulphonic acid-N-benzylanilide is obtained by reducing the nitro group of the condensation product from sodium phenolate and the 2-nitrochlorobenzene-4-sulphonic acid-N-benzylanilide obtainable by treating 2-nitrochlorobenzene-4-sulphochloride with monobenzylaniline.