Patent GB-265986-A (GB)
Title: Manufacture of acid dyestuffs of the phenonaphthosafranine series
IPC: C09B17/04
Filed: 1927-02-11
Abstract: 265,986. Geigy Akt.-Ges., J. R. Feb. 13, 1926, [Convention date]. Azine dyes; p-acetylaminophenyl-2-naphthylamine-7-sulphonic acid; di-ethyl-p-phenylenediamine sulphonic acid.-Blue to green-blue acid dyestuffs fast to alkali are obtained by condensing in neutral or alkaline medium an isorosinduline di- or tri-sulphonic acid of the formula (R and R'=hydrogen, alkyl, aralkyl or aryl) in which one sulpho group is in position 1 or 2, a second sulpho group is in position 6, and a third, if present, is in any position, with a sulphonic acid of an unsymmetrical N-alkyl-pphenylenediamine derivative or homologue, or an unsymmetrical N-acyl-p-phenylenediamine derivative or homologue (with subsequent saponification of the acyl-amino group) in which a sulpho group exists in o-position to the primary amino group. The p-phenylenediamine component may be replaced by a sulphonic acid of a p-aminophenol derivative or homologue in which a sulpho group exists in the ortho position to the primary amino group. In an example, an aqueous solution of the sodium salt of diethyl-pphenylene-diainine sulphonic acid, which may be produced by reducing the product obtained from 1-nitro-4-chlorbenzene-3-sulphonic acid and diethylamine, is mixed with a boiling alcoholic solution of phenyl-#-naphthylamine. By oxidation with sodium bichromate in the presence of acetic acid, diethyl isorosinduline-2-monosulphonic acid is obtained. This dyestuff is converted into the 2 : 6-disulphonic acid by means of bisulphite in the manner indicated in Specification 14962/98, [Class 2, Acids and salts, Organic &c.]. It dyes wool green-blue muddy tints. By boiling for several hours in the presence of sodium acetate it is condensed with 1-methyl-2-methylamino-5 aminobenzene-4-sulphonic acid whereby a dyestuff of the formula is obtained. In a second example, a phenonaphthosafraninedisulphonic acid having the formula is obtained by converting the diethylisorosinduline-1-sulphonic acid (produced according to the process of Specification 24410/97 by condensing phenyl-2-naphthylamine with the dyestuff from any diazo compound and diethylaniline-m-sulphonic acid) into the corresponding diethylisorosinduline-1 : 6-disulphonic acid and condensing the latter with 1-amino-4-diethylamino benzene- 2-sulphonic acid in a similar manner. In a third example, the sodium salt of 1-amino-4-diethylamino-2-benzene sulphonic acid is treated in aqueous solution with the sodium salt of pacetylaminophenyl-2-naphthylamine-7 - sulphonic acid (made from 2-naphthol-7-sulphonic acid and p-phenylenediamine by means of bisulphite, and acetylating) and the product oxidized with sodium bichromate in the presence of acetic acid- The dyestuff is salted out, washed and then boiled with bisulphite. After acidifying, expelling sulphur dioxide and passing air into the heated solution, it is neutralized and condensed with the sodium salt of 1-methyl-2-monoethylamino-5-aminobenzene-4-sulphonic acid when a dyestuff having the formula is obtained, which dyes animal fibres green-bluetints. The diethyl isorosinduline-1 : 6-disulphonic acid used as parent material in the second example is condensed with 1-methyl-2-hydroxybenzene-4-sulphonic acid in a fourth example- Positions 4 and 8-15 of the isorosinduline sulphonic acids may be occupied by alkyl, alkyloxy, oxy, carboxy, acidylamino, or halogen groups. 1-Methyl-2-methylamino 5 - aminobenzene - 4- sulphonic acid is prepared by reduction of the dyestuff obtained by coupling any diazo compound with 1-methyl-2-methylaminobenzene-4- sulphonic acid. 1-Methyl-2-hydroxy-5-aminobenzene-4-sulphonic acid used in example 4 is made by reducing the azo dyestuff from any diazo compound and 1- methyl-2-hydroxybenzene-4-sulphonic acid. Specifications 14961/98, [Class 2, Acids and salts,. Organic &c.], and 221,975 also are referred to.