DE743675C - Process for the production of indigoid dyes - Google Patents

Description

Process for the production of indigoid vat dyes It has been found that indigoid vat dyes can be produced by using naphthioindoxyls of the general formula wherein X is chlorine or bromine and Y is an alkoxy group, either 'oxidized or .bzw. condenses their reactive 2-derivatives with naphththioindoxyls or their reactive α-derivatives or with isatins and, if necessary, allows halogenating agents to act on the dyes obtained.

Naphththioindoxyls of this general formula or reactive ones 2-derivatives of these naphththioindoxyls are, for example, 5-chloro-6-methoxy-2, z-naphthioindoxyl, 5-chloro-6-ethoxy- 2, r-naphthtb: ioindoxyl, 5-bromo-6-methoxy-: 2, t-naphthioindoxyl, 5-broni-6-ätlioxv-2, i-naplithtliioindoxyl and the anile of these \ taphththioindoxyls, such as B. the (x- (p-Dinietliylamino -) - anil .des 5-Clilor-6-methoxy-2, i-naphththioindoxyls.

Naphththioindoxvle or their reactive ones are used for the second component x-Deri # "ate, for example, the 2, i- \ Taplitbthioindoxyl and the a- (p-Dimethylamino) -anil des 2, i-laphththioindoxyls into consideration.

The condensation of the naphththioindoxyls of the above general formula with the components mentioned, which are suitable for the production of indigoid dyes can in the presence of solvents such as alcohol, benzene, chlorobenzene or tetrachloroethane, take place. The action of halogenating agents is expediently carried out in sulfuric acid Solution or in the presence of full nitrobenzene or chlorobenzene.

The new dyes are particularly suitable for dyeing and printing the vegetable fiber, such as cotton, and color in valuable brown to olive bratines Shades. You can also by known methods in the form of their in the usual way preparable leuco ester salts can be used for dyeing.

The labeled naplithtliioindoxyls or their reactive 2-derivatives can be produced by various methods. For example, 5-chloro-6-methoxy-2, i-naplitlithioindoxy is obtained in the following way. Chlorine-6-methoxy-2-naphthalenesulfonic acid produced as a sodium salt. By treatment with phosphorus pentachloride or phosphorus oxychloride, this is converted into 5-chloro-6-metlioxy-2-naphthalenesulfocliloride, which crystallizes from benzene in colorless crystals with a melting point of 1.1.2 °. The sulfochloride obtained is converted in the customary manner by reduction and subsequent condensation with monochloroacetic acid into 5-chloro-6-methoxy -2-naphthalenethioglylcolic acid with a melting point of 157 ° to 158 °. From this thioglycolic acid, by reaction with phosphorus trichloride and aluminum chloride, 5-chloro-6-methoxy-2, i-naphththioindoxyl, which crystallizes in needles from o-dichlorobenzene, has a melting point of 265 to 266 1 .

From the 1 \ Taphthtliioitidoxylen the given general formula can be the reactive x-derivatives. such as B. the x-anile, in more familiar `` 'obtained by the action of nitroso compounds.

Compared to the known dyes, which are produced by condensation of in 5- or 7-position halogen-substituted '- \ -, aphthioindoxylenes with p-dimethylaminoanil of 5-chloro-7-methyl-3-oxytliionaphthil or dibromoisatin-x-chloride or isatin-a-chloride and after-brominating are obtained and those in bordeatiY or purple or gray Coloring shades show the dyes available according to the present experience the advantage that they produce valuable brown to brown olive tones.

The present dyes dye partly in soapfast and partly in more lightfast tones than the known dyes produced by condensation of 5, 7-dichloro- or 5, 7-dibromoisatin with 2, i- "taphththioindoxyl can be obtained. Example i: 264.5 parts of 5-chloro-6-methoxy-2, i-naphthtliioindoxyl are in iooo Parts of 12% sodium hydroxide solution dissolved in the heat with the addition of alcohol; these The solution is then added to the oxidation in portions with gentle boiling required amount of a ground, aqueous suspension of sulfur added. After boiling for a short time, the formation of the dye is complete. Then it is filtered off, the dye washed and dried. It represents a dark brown olive powder, which dissolves in concentrated sulfuric acid with a blue color. The dye whose Leuco compound is poorly soluble, dyes cotton in olive tones. Examples 26d., 5 Share 5-Clilor-6-Metlioxv -2. 1-naplltlithioindoxyl and 332 parts of 2- (p-dimethylainino) anil des 2, i- \ Taplitlitliioitidoxi-ls are heated to the boil in 600 parts of benzene, until the condensation has ended. It is then filtered and dried. The dye is a brown powder that dissolves in concentrated sulfuric acid with blue Color loosens and cotton from red-orange colored vat in full olive-tinged brown Dyes shades of very good fastness.

Beispie13 26d., 5 parts of 5-chloro-6-metlioxy- ?. i-naphththioindoxy1 and 226 parts of 5-Broniisatiii are heated in 600 parts of glacial acetic acid until condensation is terminated. It is then filtered and dried. The new dye sets brown powder, which is red-brown in concentrated sulfuric acid dissolves and dyes cotton from an orange-dyed vat in brown tones.

In this example, the 226 parts of 5-bromoisatin are replaced by 3o5 parts 5, 7-dibromoisatin, in this way a dye is obtained, the cotton dyed from a yellow vat in clear brown tones.

Beispie14 25 parts of the dye obtained in Example 3 (first paragraph) are added at 6 to zoa in goo parts of sulfuric acid (98%) and g parts of bromine: While stirring, the temperature is gradually increased to 45 to 50 ° C and at this Maintained the temperature until the burnout is complete. Then it is stirred on ice, the deposited dye is filtered off, washed with water and dried. It represents a brown powder, the cotton from a yellow vat in brown tones colors.

Claims (1)

PATENT CLAIM : -Process for the preparation of symmetrical or asymmetrical halogen-containing indigoid vat dyes, characterized in that one naphthioindoxyls of the general formula either oxidized or they or their reactive a-derivatives condensed with naphththioindoxyls or their reactive a-derivatives or with isatins and the resulting dyes optionally further halogenated. To distinguish the subject matter of the application from the state of the art, the following publications were considered in the granting procedure: German patents ... No. 455 280, 469 249; United States patent ... ... . . -1434983.