DE221529C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

CLASS 22 e. GROUP 7.

It has been found that the nitroisatin obtainable by nitrating isatin as well as its Acidyl derivatives with the 6-Ämino-3-oxy (i) -thionaphten '. · ■■■ ^

NB.

CO

Let condense into dyes, which turn brownish-yellow in the hydrosulfite vat, with a reduction of the ¹ nitro group. These colorations have a moderate degree of fastness.
If you pre-treat these vat dyes

or after their reduction to the corresponding Amino bodies (e.g. with zinc and hydrochloric acid) with halogens, such as. B. with bromine in Nitrobenzene, or with halogen-releasing substances, become very real brownish-yellow Vat dyes' obtained.

Very similar dyes are obtained if this is done by reducing nitroisatin recoverable aminodioxindole with ö-ammo-ßoxy (i) thionaphtene condensed and then treated with halogen or halogen-releasing substances.

The bodies used as starting materials show the following properties:
The Z. B. Nitroisatin obtained by nitrating isatin with concentrated nitric acid (specific weight 1.5) or with potassium nitrate in concentrated sulfuric acid or monohydrate crystallizes from glacial acetic acid in yellow needles with a melting point of 248 to 250 ° (for the product obtained by means of potassium nitrate) or 253 ° to 255 ° (for the body obtained in nitric acid (1,5)). It. Difficult to dissolve in hot alcohol, ether, benzene, glacial acetic acid, more easily in 'cold diluted' sodium hydroxide solution with a yellow to red-yellow color that does not change when heated; also in cold, concentrated sulfuric acid with a red-yellow color. 6-Amino-3 Oxy (i) thionaphtene is recrystallized from water and obtained as a brownish-gray powder with a melting point of 165 °, is almost insoluble in benzene and ligroin, and is fairly soluble in water, alcohol, ether and glacial acetic acid.

B is ρ ie 1 I. .----

12 g of nitroisatin, obtained according to Baeyer (Ber. XII, 1312), are dissolved in 50 ecm glacial acetic acid rind a solution of 10 g of 6-amino-3-oxy (i) thionaphtene added. It is boiled and left in the warmth for a while. After cooling, the condensation product crystallizes and can then be suctioned off. You wash and dry. The condensation product represents a brown vat dye, the wool and cotton in the alkaline hydrosulfite vat in brown tones stains.

Example II.

6 g of the dye obtained in Example I are mixed with 6 g of zinc, 20 ecm of hydrochloric acid (35 percent) and 40 ecm of water at 70 to 80 °. One sucks off, washes the excess

Claims (1)

Zinc out with dilute hydrochloric acid and dry. Example III. The reaction product obtained in Example II is refluxed with 5 ecm of bromine for 1 hour heated, then poured onto bisulfite solution, boiled with it, vacuumed off, washed again and dried. The body obtained in this way is a dark brown powder, the wool and cotton in the alkaline one Hydrosulfite vat dyes in brown-yellow, real tones. Instead of treating the amino product with bromine, one can also use the nitro dye treat yourself with bromine. You can also halogenation z. B. in glacial acetic acid, nitrobenzene, Carbon tetrachloride, concentrated sulfuric acid. ao Example IV. 10 g of nitroisatin are mixed with 20 g of zinc, 50 ecm Hydrochloric acid (35 percent) and ^{reduced with I 1} Z ₂ 1 water at 80 ° until almost everything has gone into solution, which takes about 2 hours. It is filtered off and the filtrate is treated with 8.6 g of 6-amino-3-oxy (i) thionaphtene, which is made into a paste with a little water. Then it is made alkaline with soda, stirred at 90 ° for about 30 minutes and filtered off with suction. The residue is treated with dilute hydrochloric acid in order to bring the zinc carbonate into solution, filtered off with suction and dried. The product is a black-brown powder, the wool and cotton in yellowish-brown Colors tones. It can be converted into a halogen derivative in the manner illustrated by Example III convict. Ρλτενϊ claim: · Process for the preparation of brownish yellow vat dyes, consisting in condensing nitroisatin ¹ or its acidyl derivatives or the corresponding aminodioxindole with 6-amino-3-oxy (i) thionaphthene and the dyes obtained in reduced or non-reduced state with halogen or halogen-releasing Treated substances.