DE863113C - Process for the preparation of thioindigoid dyes - Google Patents

Description

Process for the production of thioindigoid dyes It has been found that thioindigoid dyes can be produced when one mixtures of halogenated 7-methyl-3, - oxythionaphthenes, their halogen .. partly in 6- and partly in q-position sits, if necessary in the form of reactive derivatives, with for the production of thioindigoid dyes combined with suitable components.

The mixtures used as starting materials for the present process of 7-methyl-6-halogen-3-oxythionaphthenes and 7-methyl-q.-halogen-3-oxythionaphthenes, which preferably contain chlorine as halogen can be prepared from mixtures of z-nitro-6-halogen-i-methylbenzenes and 2-Nitroq: -halogen-i-methylbenzenes can be obtained in a manner known per se (cf. e.g. B1. Helvetica Chimica Acta, i (92.9 "Bd. 1z, p.931 / 3.2). Here it is particularly valuable that the halogenation, especially the chlorination of ortho-nitrotoluene resulting mixtures of q.- or 6-chloro-2-nitroimethylbenzene, the z. B. can contain around a third of the isomer chlorinated in the q.-position, can be used immediately. It is well known that the two isomers are only separated with material losses and on the relatively cumbersome Ways. -feasible. , The processing of the.mixtures mentioned then leads to the mixtures of 6: -Chlor- and 4-chloro-7-methyl-3-oxythio = naphthenes, which the present process can serve as starting materials.

Oxythionaphthene mixtures of this type, in which the mixing ratio z. B. 2o to 5o 1 / o "'ka.rin,. Can in a manner known per se with thioindigoid Components are combined to form dyes. As thioindi: goid components come preferably those of the oxythionaphthene series, and also those of the naphthoxythiophene series into consideration; so. are, for example, the p-dimethylaminoaniles of 4 methyl-6-chloro or @ 6-bromothiornaphthenchinons, des 5-chloro-4, 7: dimethylthionaphthenchinon, s, des 5, - Cllor-7 - methylithionaphthenchinons, des I-Chlor-2, 3-naphfhthioisatins as well as the 2, I-naphthioisatin called.

The above-mentioned oxythionaphthenic niches can also in per se known manner in reactive derivatives, z. B`. into the appropriate mixtures of p; Dimefihylaminoanilen, are converted and in this form, for example be condensed with oxythionaphthenes.

It is known that pure 6-chloro-methyl-3-oxythionaphthene or its to condense reactive derivatives with indigoid components. Surprisingly is obtained according to the present process, the iStefle of pure oxythionaphthene the much more accessible isomer mixtures used, dyes that are hardly different in their properties from those produced according to known processes from pure 6-chloro-7-methyl-3-oxythionaphthene differentiate. So z. B. the dye obtained according to the present process from a mixture of 6-chloro-7-methyl 3-oxythionaphthen and e-chloro-, 7! -methyl-3-oxythionaphthen and the p-pimethylaminoanil of 4-methyl-6-chlorothionaphthenquinone is also pure and .fast stains like that from pure 5-chloro-7 @ -methyl-3-oxythionaphthene and 4-methyl-6 - chlorothio @ naphthenchinon - p - dimethylaminoanil produced dye, while the dye is composed of 4-chloro-7-methyl-3-oxythionaphthene and the same anil The dye shown is less pure and significantly poorer in soap-fast dyeing supplies. Contrary to the general rule that a dye mixture has the properties of fastness the poorer blending component is obtained in the present process Dye mixtures in which the lower properties of one of the mixing components hidden by the better properties of the other component.

The dyes obtained by the present process are suitable for dyeing and in particular also for printing a wide variety of Wexkstoffe,. z. ! D. also of animal fibers, such as `silk or wool, but especially of cellulosic fibers such as cotton, linen, rayon and 7-ell wool made from regenerated Cellulose, as well as super polyamide fibers in front. Mostly reddish ones are obtained Tones with good fastness properties. The present method allows inter alia. even the production of pure dyes coloring in blue-red to pink tones.

The dyes obtained according to the present process can be converted into leuco ester salts of polybasic acids, e.g. D. of sulfuric acid, both emitting from the leuco compounds produced in a special operation and starting from the dyes themselves using S 0 "releasing agents, such as chlorosulfonic acid, in the presence of metals such as iron or copper , preferably in tertiary bases, such as pyridine or pyridine homologues, as solvents ... Example I I'g; 8 @ 5 g of a dry mixture of 6-chloro-7-methYl-3rOxYthionaphthen and 4-chloro-7-methyl-3-oxythionaphthene Dissolved together with 3.3.05 g of 4-methyl-6-chlorot'hionaphthenquinone-p-dimefhylaminoanil in 50 ounces of chlorobenzene and stirred for 10 to 14 hours at so up to 82 °. The dyestuff formed in good yield is filtered off and mixed with chlorobenzene rewashed.

The dye is a pink-red powder and dyes cotton, reddish-yellow vat in pure pink shades of very good fastness. It is also very easy to print. The dye can also be used well in the form of the leukoshalic acid ester: if the 33.05 g of qs-methyl-6-chlorothionaphthenquinone-p-dimethylaminoanil is replaced by 317.5 g of [methyl-6-bromothionaphthenquinone-p-dimethylaminoanil], one obtains a very similar dye.

The same dye as in paragraph I is obtained by using the indicated Mixture of oxythionaphthenes first in a mixture of the corresponding p: D @ imethylaminoanile transferred and this with 4-methyl-6-chloro-3-oxythionaphthen or: its. Carboxylic acid condensed.

The oxytihionaphthene mixture used in the present example can be obtained as follows o-nitrotoluene is at a moderate temperature in the presence chlorinated by halogen carriers. A mixture is obtained which contains around 66% 6-chloro-2-nitroz-niet'hylbenzene and around 3q.0 / 0 q.-chloro-, 2.-nitro-I-methylbenzene. This mixture will reduced, the amine mixture obtained is diazotized and reacted with xanthates and further processed in the usual way to form a mixture of the corresponding Oxyt'hionap'hthene. Examples 19.85 g of the dry oxythionaphthene mixture used in Example i are with 34e5 g of 5 - chlorine -4, 7 - dimeth @ lthionaphthenchinon - p - dimethylaminoanil in 400 ccm of chlorobenzene at 80 to & 2 ° during, I stirred for hours. Drer in good yield - obtained red dye gives on cotton and other cellulosic Textiles a strong red with good fastness properties. the The color matches that of the pure 6-chloro-7-methylfhioindoxyl dye match.

EXAMPLE 3 19.85 g of the oxythionaphthene mixture used in Example i are stirred with 36.6 g of p-dimethylaminoanil of i-chloro-2,3-naphthioindoxyl in 500 cc of chlorobenzene for 14 hours at 80 to 8 °. The violet dye formed in good yield is filtered off and washed with the solvent. It dyes cotton and other textiles in beautiful purple tones with very good fastness properties, just like the dye made from pure 6-chloro-7-methyl-3-oxythionaphthene.

If 33.2 g of p-dimethylaminoanil des 2, i-naphthioindoxyls are used instead of the 36.6 g of the specified anil, one in shades of Bordeaux is obtained coloring dye.

Claims (2)

PATENT CLAIMS: i. Process for the production of thioindigoid dyes, characterized in that mixtures of halogenated 7-methyl-3-oxythionaphthes are the halogen of which is partly in the 6-position and partly in the 4-position, optionally in the form reactive derivatives, with suitable for the production of thioindigoid dyes Components combined and optionally the resulting dyes in leuco ester salts convicted. 2. The method according to claim i, characterized by the use of the correspondingly chlorinated 7-methyl-3-oxythionaphthene.