CH268432A - Process for the production of a new dye. - Google Patents

Description

  

  <B> Additional patent </B> to the main patent No. 261976. Process for the production of a new dye. The present invention relates to a process for producing a new dye, which is characterized in that 5-benzoylamino-1,1'-dianthrimide-2,2'-carbazole in the presence of an organic amide derived from a secondary amine with a metal is reduced and treated with a sulfating agent to form the corresponding leuco sulfuric acid ester.



  The new dye is a yellow-brown powder that dissolves in water to form a yellow-brown solution.



  Examples of amides which are suitable for the above reaction are the amides derived from carboxylic acids, for example dimethylformamide, diethylformamide, dimethyl acetamide and tetramethylurea, and the amides derived from sulfonic acids, for example N, N-diethyl p-toluenesulfonamide, called. You can also diluents, such as. B.

   Add acetone and acetonitrile. <I> Example 1: </I> 5.4 parts of 5-benzoylamino-1,1'-dianthrimide-2,2'-rarbazole (which can be obtained by ring closure from 5-benzoylamino-1,1'-dianthrimide ), 4 parts of zinc powder, 1 part of sodium 2-naphthalenesulfonate and 40 parts of dimethylformamide are stirred together in an inert atmosphere at 170 ° C. for one hour.

   The product obtained by reacting 21 parts of methylehlorsulfonate and 40 parts of dimethylformamide is added and the mixture is stirred at 00 ° C. for 30 minutes. A brown solution is obtained which has a green fluorescence. This solution is then added to 400 parts of an aqueous 10% sodium carbonate solution. The mixture is filtered and the filtrate is distilled in vacuo until sodium sulfate appears in the still. begins to part.

   Water is then added gradually to keep the volume of the stills in the still constant, and the distillation is continued until about 500 parts of water have been added. The leuco sulfuric acid ester is then salted out, filtered off, washed with a 10% strength aqueous sodium carbonate solution, mixed with dextrin and dried in vacuo.

    <I> Example 2: </I> 5.4 parts of 5-benzoylamino-1,1'-dianthrimide-2,2'-carbazole, 4 parts of zinc dust, 1 part of sodium 2-naphthalene sulfonate and 40 parts of di- methylformamide are stirred together at 170 ° C. for one hour in an inert atmosphere.

   The reaction mixture is introduced into 60 parts of a stirred suspension of dimethylformamide-sulfur trioxide in dimethylformamide (with a content of 40% sulfur trioxide) at 00 ° C. in an inert atmosphere.

   The mixture is stirred for 30 minutes and the leuco-sulfuric acid ester is isolated in the manner described in Example 1. <I> Example 3: </I> 5.4 parts of 5-benzoylamino-1,1'-dianthrimide-2,2'-carbazole, 4 parts of zinc dust, 1 part of methyltriethylammonium chloride, 40 parts of N-formomorpholide and 10 parts of acetone are stirred at 250 ° C. for 5 minutes.

       The product obtained by reacting 40 parts of methylchlorosulfonate and 60 parts of N-formomorpholide is then added and the mixture obtained in this way is stirred at 00 ° C. for 10 minutes. A brown solution with a green fluorescence is obtained, from which the leuco-sulfuric acid ester is isolated in the manner described in Example 1.

 

Claims (1)

Claim: a process for the preparation of a new dye, characterized in that 5-benzoylamino-1,1'-dianthrimide-2,2'-carbazole is reduced with a metal in the presence of an organic amide derived from a secondary amine and to form the corresponding Leucosulfuric acid ester is treated with a sulfating agent. The new dye is a yellow-brown powder that dissolves in water to form a yellow-brown solution.