DE27954C - Process for the preparation of sulfonic acids of benzidine and benzidine sulfonic, as well as for the preparation of new azo dyes from the tetrazo compounds of the same and amines, phenols or their sulfonic acids - Google Patents

Description

IMPERIAL

PATENT OFFICE.

f-

or their sulfonic acids.

Benzidinedisulfonic created by Peter Griefs (Reports of the German Chemical Society, Volume 14, p 300) by heating benzidine with twice the amount of fuming sulfuric acid in an oil bath to about 170 ⁰ C. short time.

We have found that if you extended period, heated at any rate a quarter of an hour, and particularly at temperatures higher than 170 ⁰ next to the benzidinedisulfonic in varying amounts also Benzidintrisulfosäure and Benzidintetrasulfosäure, and also mono- and disulfonic arise which the latter two are probably sulfonic acids of a benzidine sulfone, and so are their forms

SO ₂

SO ₂

C ₆ H ₂ NH ₂ SO ₃ H

C ₆ H ₃ NH ₂
, and C ₆ H ₂ NH ₂ SO ₃ H

QH ₂ NH ₂ SO ₃ H
will be.

From these five bodies arise those newly discovered by us, especially the new disulfonic acid of benzide sulfone, as well as the TrP ~ and tetrasulfonic acid of benzidine the more abundant, the longer you heat and the higher the temperature, but without causing charring, increases; on the other hand, only in small and hardly worthwhile amounts, if only the temperature and duration are used, which for the production of Griefs' disulfonic acid is required. The monosulfonic acid of benzidine sulfone can be converted into the corresponding one Disulfonic acid and the disulfonic acid of benzidine into the corresponding tri- and tetrasulfonic acid transfer by further heating with sulfuric acid.

We have found it beneficial at temperatures from 170 to 2oo ° for about an hour or more, but notice that that time and temperature complement and replace one another, so that one is at a higher temperature can interrupt the process earlier.

We have also found that this result is also obtained if the sulfuric acid Salt or another salt of the benzidine in place of the free benzidine in the processing takes. Furthermore, the reaction proceeds all the more advantageously when there is a large excess of sulfuric acid, i.e. about three to four or more times instead of twice Amount of weight into which processing takes.

Instead of fuming sulfuric acid, one can also use pyrosulfuric acid, sulfuric anhydride or the monochlorohydrin or mixture of these substances with sulfuric acid use, whereby the quantity naturally varies accordingly, on the other hand it had to be used in the application of the 66 sulfuric acid, which in itself is not excluded, its amount and the Time of heating. can be increased significantly.

The melt, which is essentially the mixture of the excess sulfuric acid Disulfonic acid of benzidine and the above

ten of the substances we have newly discovered is dissolved in water (about twenty times the amount of the sulfuric acid or free benzidine used) entered with stirring.

The tri- and tetrasulfonic acids of benzidine dissolve in the water while the Griefs' see disulfonic acid, as well as the above Mono- and disulfonic acids of benzidine sulfone settle in an intimate mixture to the bottom, mechanically separated from the lye and can be washed out with water if desired.

II. The tri- and tetrasulfonic acid of benzidine give in combination with certain Amines and phenols, which are mentioned below, valuable red to violet colors of (when using both acids) often almost the same nuances and properties, which is why they can be used together as well as separately.

For the purpose of removing the excess sulfuric acid one can use the mixture either evaporate until the amount of sulphonic acid crystallizes out, or by means of soda, lime or theirs Dull carbonates and the like.

In order to separate these two bodies from one another, we use the method of representation and the separation of their barite salts, since, as we have found, the barium salt of Trisulfonic acid is easily soluble in water, whereas tetrasulfonic acid is sparingly soluble. the From this, the type of separation is obvious for the expert.

However, several other methods of separation can easily be found permit.

III. The mixture of the Griefs see disulfonic acids of the benzidine and the two sulfonic acids of the benzidine sulfone would with the below named amines and phenols and their sulfonic acids result in red-violet to violet colors and can therefore be used in this combination.

The disulphonic acid of benzidine gives, as Peter Griefs already cited, with the sulfonic acids of the naphthols, violet to brownish-red dyes. Surrender to it the mentioned two newly discovered sulfonic acids of benzidine sulfone, as we have done through numerous Experiments have found rothe in combination with certain phenols and their sulfonic acids to purple and in combination with certain amines and their sulfonic acids purple to blue Dyes.

It may therefore be desirable to move these new bodies from one another as well separate.

We have found the following procedure for this:

If you boil the mixture with a large amount of water, the new one dissolves Benzidinsulfons disulfonic acid on, while the other two bodies themselves in hot Are almost insoluble in water. Didn't get all of the new disulfonic acid when it was first boiled dissolved, it is filtered off and the residue is renewed and possibly more often with it Boiled water.

Since the substance dissolved here, namely the new disulfonic acid, is the most valuable of the mixture one will try to win it as completely as possible. It is obtained from the solution in the form of a salt Neutralize them with a suitable base or in the free state by adding Sulfuric acid or hydrochloric acid to the previously sufficiently concentrated solution, or by salting out with table salt and, albeit less conveniently, by simply evaporating the solution.

The mixture of the benzidine sulfone remaining after the disulfonic acid has been extracted Griefs disulfonic acid of benzidine and the new monosulfonic acid of benzidine sulfone can be separated in such a way that it is treated with water with the addition of an excess is boiled from finely divided carbonate of lime or barite or the like. This dissolves the mixture, and the lime or barium salts of both sulfonic acids are formed.

The excess carbonate of lime (barite) is separated mechanically and the solution is evaporated a.

The sparingly soluble lime or barium salt of the monosulfonic acid of benzidine sulfone When the concentrated solution cools, it precipitates in yellow crystals and becomes mechanical separated, while finally the salt of Griefs' benzididinesulfonic acid in solution remains and by further evaporation and crystallization or by salting out or otherwise Way can be represented freely.

IV. Since, as already mentioned, the disulphonic acid of benzidine sulphone is the most valuable of the bodies found, the monosulphonic acid of benzidine sulphone can also be conveniently converted into its disulphonic acid. This is done by prolonged heating at twice or gröfseren amount of fuming sulfuric acid or their equivalents called to 170 ⁰ and above. ^

V. The representation of dyes by means of the newly discovered sulfonic acids takes place in the well-known way that they can be converted into their resp. Tetrazo compounds transferred and these on the amines and phenols in solution and allows their sulfonic acids to act.

The novelty of the methods mentioned below therefore essentially consists in the Choice of the substances prescribed here for the purpose of achieving certain new dyes,

while otherwise the known equivalent proportions are to be taken as a basis, and the further procedure is known to the practical paint chemist.
For one prepares in this way:

A. Using the Griefs disulfonic acid of benzidine:

ι. a dark red dye by combining it with betanaphthylamine;

2. a purple-red dye through its. Combination with dimethylbetanaphtylamine;

3. a red dye by combination with naphthoic acid;

4. Red dyes by combining with the various betanaphthylamine sulfonic acids.

B. Using the tri- and Tetrasulfo- ¹ acid of benzidine:

1. a brownish-red dye by combination with betanaphtol;

2. a scarlet color by combination with Bayer's alpha monosulfonic acid of betanaphthol;

3. dark red dyes by combining with the two disulfonic acids of betanaphthol.

C. Using the new monosulfonic acid of benzidine sulfone:

1. a red-violet dye by combination with alphanaphtylamine;

2. red dyes by combining with betanaphthylamine and its sulfonic acids;

3. a brown-purple dye by combination with naphthionic acid;

4. red dyes by combining with betanaphtol and its mono- and disulfonic acids;

5. a purple dye by combining with dimethylbetanaphtylamine.

D. Using the disulfonic acid of benzidine sulfone:

1. a brown-purple dye by combination with alphanaphtylamine;

2. a brown-purple dye by combination with naphthionic acid;

3. violet dyes by combining with betanaphthylamine and its sulfonic acids;

4. a blue dye by combination with phenylbetanaphtylamine;

5. a blue dye by combination with dimethylbetanaphtylamine;

. 6. a dark red dye by combination with betanaphtol;

7. a dark red dye by combination with Bayer's alpha monosulfonic acid of betanaphthol;

8. a blood-red dye by combination with Schaffer's betamonosulfonic acid of betanaphthol;

9. red dyes with the two disulfonic acids of betanaphthol.

Claims (5)

Patent Claims: 1. The generation of a new tri- and tetrasulphonic acid of benzidine, a new monosulphonic and a new disulphonic acid of benzidine sulphone in a mixture with the disulphonic acid of benzidine found by Peter Griefs by heating free benzidine or its salts for more than a quarter of an hour, namely of sulfuric acid benzidine, with two or more amounts of fuming or 66 sulfuric acid or an analogous amount of pyrosulfuric acid or sulfuric acid anhydride or monochlorohydrin at temperatures above 170 ^° C .; also the separation of the tri- and tetrasulfonic acid of benzidine from the other substances mentioned by pouring the melt into water. 2. The process of separating the trisulfonic acid from the tetrasulfonic acid of benzidine by virtue of the easy solubility of the barite salt of the former and the poor solubility of the barite salt of the latter in water. 3. The process of separating the new disulfonic acid of benzidine sulfone from the with it mixed monosulfonic acid of benzidine sulfone and Grief's disulfonic acid of the benzidine by boiling the mixture with water, as well as the process of separating the monosulfonic acid of the benzidine sulfone from the remaining mixture by representation and! crystallization of the sparingly soluble lime or barium salt thereof. 4. The conversion of the monosulphonic acid of Benzidinsulfons in their disulfonic acid by prolonged heating with fuming sulfuric acid or their equivalents to about 170 ⁰ C. 5. The method of preparing the new dyes identified under V. above by pairing the sulfonic acids given there under A, B, C and D. of benzidine and benzidine sulfone in the form of their tetrazo compounds with the designated amides and phenols and their sulfonic acids.