DE269842C - - Google Patents

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- ■ JVs 269842 - CLASS \ 2p. GROUP

FARBENFABRIKEN vorm. FRIEDR. BAYER & CO. in LEVERKUSEN b. CÖLN and ELBERFELD.

Process for the preparation of nitrogen-containing anthraquinone derivatives. Patented in the German Empire on January 21, 1913.

It has been found that the diazo compounds of the o-aminomethylanthraquinones or their derivatives when heated in a weakly mineral acid solution or during treatment be converted into new nitrogenous products with mineral acid binding agents » which are derived from the diazo compounds through the escape of the elements of water. The reaction would then be illustrated by the following equation:

35

CO, CO '

, N =

-E ₉ O

CO.

CO

■ ΝH or C _B

CH ' , CO,

CO '

'CrH ₀

40

₄₅

! 5 so that the new bodies as indazole derivatives are to be addressed.

It could not be foreseen that the products mentioned would form so easily from the o-diazomethylanthraquinones, since o-diazomethylanthraquinones have already been subjected to various chemical reactions without the occurrence of such ring formations having been observed (cf.e.g. Ber. Of the German chemical society 16 [1883], p. 700, as well as patents 184495 and 215006, example 3, class 12 ⁰ ).

The new products are valuable starting materials for the representation of dyes.

Example 1.

The diazo sulfate, obtained in the usual way from 2 parts of 1-amino - 2 - methylanthraquinone, is heated to boiling with 100 parts of water until unchanged diazo compound does not there is more to be proven, which is the case after a short time. The resulting precipitate is now nitrided, washed, dried and made from a mixture of nitrobenzene and Pyridine or recrystallized from sulfuric acid. A yellow colored product is obtained in this way dissolves cherry red in sulfuric acid; when this solution is poured into water, separate yellow flakes off. The product is sparingly soluble in organic solvents.

Example 2.

The diazo sulfate obtained from 5 parts of ι -amino-a-methyl ^ -chloranthraquinone (see patent specification 131402, class 12 q, example 3) 250 parts of water dissolved and filtered,

60

in

7 parts of sodium bicarbonate are then added and stirred at 50 ° C. until the diazo compound has reacted.

The cleaning is carried out as in Example 1.
The product can be recrystallized from sulfuric acid and forms yellow needles, which are dissolved in sulfuric acid at 66 ° Be. loosen with blue-red paint.

Example 3.

The diazo sulfate from 1 part i-amino-2-me-

/, thylanthraquinone is an-

. dough and added to a mixture of 25 parts of water and 2 parts of pyridine.

After brief stirring in the cold, ■ a brown gelatinous precipitate separates out, , which after about two hours. Stand up

· / 'Boils and is vacuumed. The reaction product is boiled with glacial acetic acid; the insoluble residue, which makes up the bulk of the product, is identical to that in Example 1 described body. The mother liquor in glacial acetic acid is obtained by dilution with water a body that is more readily soluble in organic solvents, that of pyridine recrystallized, forms yellow needles with a melting point of 260 °, which are concentrated in Sulfuric acid yellow-orange, dissolve in oleum of 40 percent red-brown. Its solution in xylene gives a purple-black precipitate with alcoholic potash. The body has the same Composition like the poorly soluble main product described above.

This easily soluble body is obtained almost exclusively when one is anhydrous Pyridine can act on the dry diazosulfate, or if i-amino-2-methylanthraquinone treated in glacial acetic acid solution with nitrous acid releasing agents.

Example 4.

The sharply dried diazo sulfate from 1 part of i-amino-2-methylanthraquinone is cooled with cooling stirred with about 5 parts of anhydrous pyridine. Under self-heating, which by Cooling is to be moderate, the whole solidifies to a light brown paste of the reaction product, which is sucked off after diluting with water. After recrystallization from pyridine, it has a melting point of 260 ° and is found to be identical to the by-product described in Example 3.

Example 5.

2 parts of i-amino-2-methylaminoanthraquinone are dissolved in 50 parts of boiling glacial acetic acid and with vigorous stirring for so long with sodium nitrite added until all of the starting material has been converted, which can be seen from the fact that a sample of the glacial acetic acid solution is mixed with water diluted, no longer a red, but a pure yellow precipitate. The received Solution is then filtered hot; a small residue remains on the filter Product soluble in red in concentrated sulfuric acid, which is identical to that in example ι is the body described. The filtrate is diluted until the start of crystallization a body that corresponds to the one described in the previous example.

Instead of sodium nitrite, amyl nitrite can also be used.

Example 6.

A suspension of 2 parts of 1-amino-2-methyl-4-chloroanthraquinone in 50 parts of boiling glacial acetic acid is gradually mixed with sodium nitrite (about 2 parts) while stirring added until the starting material has disappeared. The reaction product separates already in the boiling heat in the form of small brown needles. Recrystallized from nitrobenzene, it forms shiny, brown-yellow long needles, -which are in concentrated sulfuric acid solve with yellow paint.

The reaction with other derivatives of the o-aminomethylanthraquinones proceeds quite analogously.

Claims (1)

Patent claim: Process for the preparation of nitrogen-containing anthraquinone derivatives, which are derived fromo-diazomethylanthraquinones or their salts by elimination of the elements of water or the relevant acid, consisting in that diazonium salts of o-aminomethylanthraquinones or their derivatives are heated in weakly acidic solution or bind with mineral acid means treated, or in that o-Aminomethylanthrachinone in absence ^x standardized treated by mineral acids with nitrous acid.