Patent GB-407578-A (GB)
Title: Manufacture of indigoid dyestuffs
IPC: C09B7/10
Filed: 1933-06-14
Abstract: Unsymmetrical indigoid dyestuffs are obtained by condensing 3-oxythionaphthenes, their reactive 2-derivatives or the corresponding thionaphthenequinones with a 3-oxythionaphthene having the general formula <FORM:0407578/IV/1> in which one x is halogen, the other x alkyl, one y also alkyl and the other y hydrogen, the two alkyl groups being in the meta position to one another and the two components in a different state of oxidation and differing in the manner in which the fused on benzene rings are substituted.  In examples: (1) 3-oxythionaphthene 2-(p-dimethylaminoanil) is condensed with 7-chlor-4 : 6-dimethyl-3-oxythionaphthene or 4-chlor-5 : 7-dimethyl-3-oxythionaphthene; the dyestuff obtained by using the former oxythionaphthene dyes cotton rose tints from the usual vat; the dyeing of wool, silk and artificial silk, e.g. viscose is mentioned; (2) 7-chlor : 4 : 6-dimethyl-3-oxythionaphthene is condensed with 6-ethoxy-3-oxythionaphthene-2-(p-dimethylaminoanil), 5-chlor-7-methyl-3-oxythionaphthene-2-(p-dimethylaminoanil) or 2 : 3-naphthothioindoxyl-2-(p-dimethylaminoanil); (3) 4 : chlor-5 : 7-dimethyl-3-oxythionaphthene is condensed with 2 : 1-naphthothioindoxyl-2-(p-dimethylaminoanil).  The properties of the dyestuffs obtained by condensing the following pairs of components are tabulated: 7 - chlor - 4 : 6 - dimethyl - 3 - oxythionaphthene with 5-methyl-6-chlor-3-oxythionaphthene-2-(p-dimethylaminoanil) or 4-methyl-6-chlor-3-oxythionaphthene-2-(p-dimethylaminoanil) or 1 : 2- or 2 : 1-naphthothioindoxyl-2-(p-dimethylaminoanil) or with 1-chlor-2 : 3-naphthothioindoxyl-2-(p-dimethylaminoanil), 4-chlor-5 : 7-dimethyl-3-oxythionaphthene with the 2-p-dimethylaminoanils of 5 - chlor - 7 - methyl - 3-oxythionaphthene or 1-chlor-2 : 3-naphthothioindoxyl, or 1 : 2- or 2 : 3-naphthothio-indoxyl, or 6-ethoxy-3-oxythionaphthene or with 5-methyl-6-chlor-3-oxythionaphthene and 4-chlor-5 : 7-dimethyl-3-oxythionaphthene with 5 - chlor - 3 - oxythionaphthene - 2 - (p-dimethylaminoanil).  7-Brom-4 : 6-dimethyl-3-oxythionaphthene and 4 - brom - 5 : 7 - dimethyl - 3 - oxythionaphthene-2-carboxylic acid are also mentioned.  The dyestuffs may be halogenated. 7-Chlor-4 : 6-dimethyl-3-oxythionaphthene and 4-chlor-5 : 7-dimethyl-3-oxythionaphthene and their 2 : 3-quinones and 2-derivatives.  1-Amino-2 : 4-dimethyl-6-benzenesulphonic acid is converted into the corresponding 1-chlor derivative by diazotisation and treatment with cuprous chloride, and yields 1-chlor-2 : 4-dimethyl-6-benzene-sulphochloride by treating with phosphorus pentachloride.  By reducing to the mercaptan, and condensation with chloracetic acid, 1-chlor-2 : 4-dimethyl-6-phenylthioglycollic acid is obtained which on ring closure with phosphorus trichloride and aluminium chloride gives 7-chlor-4 : 6-dimethyl-3-oxythionaphthene. 1-Chlor-2 : 4-dimethyl-5-benzenesulphochloride is similarly converted into 4-chlor-5 : 7-dimethyl-3-oxythionaphthene.  The production of the corresponding 2-anils, oximes and halides of the oxythionaphthenes by means of nitroso compounds, nitrous acid and halogens respectively is mentioned.