SU148066A1 - Method for producing 1,4-diamino-2,3-dicyananthraquinone and 1-hydroxy-4-amino-2,3-dicyananthraquinone - Google Patents

Description

Known methods for the preparation of 1,4-diamino-2,3-dicyc anthraquinone and 1-hydroxy-4-amino-2,3-DICiananthraquinone are intermediate products in the synthesis of dyes for synthetic fibers (e.g. cellulose acetate and polyethylene terephthalate), sodium cyanide in aqueous media, respectively, for 1,4-diaminoanthraquinone-2 sulfonic acid and 1-hydroxy-4-amacoangrahinon-2-sulfonic acid.

Known methods result in a mixture of these dicyananthraquinones with the corresponding monocyanosubstituted, and to obtain them in pure form, it is necessary that they be separated from the by-products.

In this invention, in order to increase the yield and improve the quality of the target products, it is proposed to carry out the process in the presence of sodium nitrite or sodium nitrobenzene sulfate sodium, which are introduced into the reaction medium together with sodium cyanide.

The dicyananthraquinones obtained by the proposed method contain only a small admixture of monocyanate substituted and can be used to obtain dyes without prior purification.

In order to avoid the danger of poisoning when filtering the reaction mixture containing excess sodium cyanide, after cyanation is completed, the cyanic salts are neutralized by treating sodium thiosulfate. Such treatment does not reduce the yield and does not impair the quality of the product. Example I. 86.7 g of sulfate paste obtained by sulfating leuco-1,4-aminooxyanthraquinone (ed. St. 144920) containing 20.0 g of the basic substance, 44.0 g sulfuric acid and 22.7 g of water, stirred for 30 minutes at a temperature of 100 ° C with 320 ml of water and 32 g of caustic soda. The temperature is then lowered to 40 ° and 10 g of sodium sulphate, 34.6 g of sodium cyanide (88.7%) are added.

№ 148066

and 5 g of sodium nitrite. The mixture is heated to 90 °, stirred at this temperature for 5 hours, cooled to 80 °, another 200 ml of water and 150 g of crystalline sodium thiosulfate are added and stirred for 1 hour at 80 °. After cooling to room temperature, the precipitate is filtered, washed successively with 10% sodium chloride solution, 100 ml of 5% hydrochloric acid solution, hot water and dried at a temperature of 80-90 °. The output of 1-hydroxy-4-amino-2,3-dicanoanthraquinone-12, 5 g (72% of theoretical).

Example 2. 51.4 g of a 1,4-piamino-anthraquinone-2 sulfonic acid hydrochloric paste obtained by leuko-1,4-diamino-anthraquinone sulfirovany with a content of 21.6 g of the basic substance, 1.5 g of hydrochloric acid and 28.3 g of water stir for 30 minutes at a temperature of 100 ° with 340 ml of water and 3.9 g of caustic soda. The temperature is then lowered to 40 ° and 1.43 g of sodium carbonate, 22.9 g of sodium cyanide (88.7%) and 12.4 g of sodium nitrobenzenesulfonic acid are added. The mixture is heated to 90 °, stirred at this temperature for 5 hours, cooled to 80 ° and 103 g of crystalline sodium thiosulfate are added. Stir for 1 hour at 80 ° and cool to room temperature. The precipitate is filtered off, washed with hot water and dried at a temperature of 80-90 °. Yield of 1,4-diamino-2,3-dicyananthraquinone-13, 9 g (71.0% of the theoretical).

The proposed method is very simple and allows to obtain semi-finished products for the production of blue dyes for Dacron and apate silk.

Subject invention

The method of obtaining 1,4-diamino-2,3-dicyananthraquinone and 1-hydroxy4-amino-2, 3-dicyapantraquinone by the action of sodium cyanide in aqueous medium, respectively, on 1, -4-diaminoanthraquinone-2-sulfonic acid and 1-hydroxy-4- aminoanthraquinone-2-sulfoxe slot, characterized in that, in order to increase the yield and improve the quality of the target products, the process is carried out in the presence of sodium nitrite or m-nitrobenzenesulfonic sodium.