Patent GB-245865-A (GB)
Title: The manufacture of í¡ í¡w intermediate compounds and of azo dyestuffs
Filed: 1924-10-21
Abstract: 245,865. British Dyestuffs Corporation, Ltd., and Saunders, K. H. Oct. 21,1924. Sulphinic acids; nitro-and aminodiarylsulphones.-Sulphinic acids of phenol-o-carboxylic acids are obtained by reducing sulphochlorides of phenol-o-carboxylic acids (Specification 18430/13) with reducing agents other than alkaline sodium sulphite. By condensing with aromatic nitro compounds having labile halogen atoms, and particularly with o-halogennitro compounds, they yield nitrosuphones which can be reduced to aminosulphones. According to examples (1) salicyclic acid 5-sulphochloride is reduced with zinc dust in alcoholic solution, if desired in presence of an acid-binding agent such as chalk, the zinc salt of the sulphinate converted to a solution of the sodium salt by means of sodium hydroxide or carbonate and a double compound of the acid and its acid sodium salt separated by acidification; the corresponding sulphinic acids can similarly be obtained from o-cresotinic sulphochloride and 3-chlorosalicylic sulphochloride: (2) salicylic sulphinic acid is condensed with 4-chlor-3-nitrobenzenesulphonic acid and the nitrosulphone reduced, if desired without isolation, by means of zinc or iron and acid, stannous chloride, sodium sulphide, &c.: the nitrosulphone may be chlorinated. presumably in the o-position to the hydroxyl group, by treatment with sodium hypochlorite: (3) o-cresotinic sulphinic acid is condensed with 2 : 4-dinitrochlorobenzene and one or both of the nitro groups reduced with stannous chloride; the diamino compound yields monoacidyl derivatives, the oxalyl derivative being specified. Nitrosulphones from 2-nitrochlorbenzene-4-sulpho-or carboxylic acid, 2-nitro- 4-aldehydo-1-chlorbenzene, 2: 6-dinitro-1-chlorbenzene-4-sulpho acid, and 2 : 4-dinitro-1-chlorbenzene or naphthalene are also mentioned. Azo-dyes are obtained by coupling the diazo compounds of the above-described amino-, nitroamino-, or monoacidyldiamino-sulphones with the usual components. Dis- and poly-azo dyes may be built up in the known manner; thus the diazotized aminosulphones may be coupled with a-naphthylamine, Cleve's acid, &c., rediazotized, and coupled further; or the diazesulphones may be coupled with a component such as H-acid, which can then be coupled under different conditions with another simple diazo compound or with a complex diazo compound such as that obtained from 1 mol. tetrazotized benzidine and 1 mol. sadicyclic acid. The products dye wool in shades, but little altered by after-chroming- they are especially suitable for chrome-printing on cotton. According to examples dyestuffs may be obtained from the following components: -monoazo dyes from 4-ox y -3 : 4<1>-dicarboxy- 2<1>-aminodiphenylsulphone, or 4-oxy-3-carboxy- 2<1>-aminodiphenylsulphone-4<1>-sulpho acid or its 5-merthyl derivative, and 2:3-oxynaphthoic anilide, 2-naphthol, 2-naphthylamine, ethyl-2- naphthylamine phenylmethylpyrazolone, ethylbenzylamine, 1-naphthol-4-sulphonic acid, or 1 : 8-dioxynaphthalene-3 : 6-disulphonic acid; 5- methyl - 4 - oxy - 3 - carboxy - 4<1>-nitro-2<1>-aminodiphenylsulphone, and 2-naphthylamine-methyl-#- sulphonic acid : mono-oxalyl-2<1>: 4<1>-diamino-4- oxy-3-carboxydiphenylsulphone and 2-naphthol: a secondary disazo dye from 4-oxy-3-carboxy-2<1>- aminodiphenylsulphone.-4<1>-sulphonic acid, p-xylidine, and acetyl-2 : 5: 7-acid : a trisazo dye from benzidine, phenol and the monoazo dye from 4- oxy-3-carboxy-2<1>-aminodiphensulphone-4<1> - sur phonic acid and H-acid (acid coupling).