DE1113053B - Process for the preparation of Kuepen dyes of the 1,3,4-oxdiazole series - Google Patents

Description

Process for the preparation of vat dyes of the 1,3,4-oxdiazole series From German patent 544 892 it is known that 4-cyclohexyl-1,2,4-triazoles obtained when N-cyclohexylimide chlorides are reacted with acid hydrazides.

It has now been found that, surprisingly, no 1,2,4-triazoles but rather vat dyes of the 1,3,4-oxdiazole series are obtained if N-substituted imide chlorides are allowed to act on monohydrazides of 1-aminoanthraquinone-2-carboxylic acids. The implementation proceeds according to the following schematic equation: Here, R, stands for a 1-aminoanthraquinonyl (2) radical, which in turn can carry further substituents, for example amino or acylamino groups, such as benzoylamino groups. R2 can e.g. B. an optionally further substituents such as halogen atoms or nitro groups containing mono- or polynuclear aromatic, heterocyclic, non-linkable or linkable radical, such as an anthraquinonyl radical. R3 can be a simple radical, for example an aliphatic radical or an aromatic radical which is optionally also substituted. One of the implementation partners R, or R, can be the grouping, respectively contained several times. As 1-aminoanthraquinone-2-carboxylic acids are, for. B. 1-Aminoanthraquinone-2-carboxylic acid, 1-amino-4- (or -5-) nitroanthraquinone-2-carboxylic acid, 1-amino-4- (or -5-) halogenanthraquinone -2 - carboxylic acids, 1,4- (or -5-) diaminoanthraquinone-2-carboxylic acid, 1-amino-4- (or-5-) acylaminoanthraquinone-2-carboxylic acids, 1-amino-4- (or -5) quinazolylaminoanthraquinone-2-carboxylic acids or 1-amino -4- (or -5-) triazinylaminoanthraquinone-2-carboxylic acids called.

Imide chlorides of the type mentioned above are produced by conventional methods, z. B. from acylated arylamines by reaction with halogenating agents such as Thionyl chloride or phosphorus pentachloride. You can as such for the method of the invention can be used. But it is also possible such To let imide chlorides arise only in the reaction mixture, for example by appropriately acylated alkyl or aryl amines treated with halogenating agents.

The reaction takes place at a moderately elevated to elevated temperature of from about 50 to about 165.degree. C., preferably between 70 and 150.degree. It is expedient to work in the presence of solvents and / or diluents, such as N-methylpyrrolidone, pyridine, quinone or nitrobenzene. If neutral solvents and / or diluents are used, it is advantageous to add alkaline compounds, such as quinoline or dimethylaniline, to the reaction mixture. The reaction is usually complete within about 2 hours. It is expedient to start from stoichiometric amounts of the reaction participants. Only in the case of N-substituted imide chlorides, which the group contained only once, it is advantageous to use a small excess (approximately 1 to 1.1 moles per mole of monohydrazide).

The new process requires neither condensation agents to form the oxdiazole ring nor for the implementation of ring closure reactions conventionally used catalysts. It is therefore particularly characterized by the fact that it is used for the production of connections is suitable, which, bound to an anthraquinone system, sensitive substituents, z. B. primary amino groups wear. The 1,3,4-oxdiazoles obtainable in this way are valuable Vat dyes.

Dyes of this type are already known. But so far they are only in a cumbersome way, namely by reacting monohydrazides of 1-aminoanthraquinone-2-carboxylic acids Carboxylic acids that cannot be or cannot be linked to acid halides and dehydration from the resulting diacylhydrazides to win. Instead of monohydrazides of 1-Aminoanthracbinon-2-carboxylic acids can also be used from monohydrazides of 1-halogen or 1-nitroanthraquinone-2-carboxylic acids go out and in the so obtainable Derivatives of 1,3,4-oxdiazole those in the 1-position on the anthraquinone system Halogen atoms, such as chlorine or bromine atoms, or nitro groups, if necessary in in a manner known per se, for. B. by treatment with ammonia or in the case of halogen atoms by reacting with p-toluenesulfonic acid amide and subsequent cleavage of the remainder of the p-toluenesulfonic acid or, in the case of nitro groups, by vatting, by amino groups substitute. If the monohydrazides of 1-nitroanthraquinone-2-carboxylic acids are used as starting materials, in this way one obtains derivatives of 1,3,4-oxdiazole, which as such are already used as vat dyes can serve. Compared to the well-known two- or three-stage process the new process has all the advantages of a one-step process.

The parts given in the following examples are parts by weight.

Example I A. A mixture of 10 parts of 1-aminoanthraquinone-2-carboxylic acid hydrazide and 10 parts of T-chlorophenylbenzimidyl chloride is stirred in 150 parts of nitrobenzene for 1 hour at 120.degree. C. and then for 1 hour at 150.degree. The mixture is allowed to cool, the precipitated reaction material is filtered off with suction, washed with methanol and dried. 9 parts of the oxdiazole of the formula are obtained in the form of red needles with a melting point of 312 ° C.

B. 10 parts of 1-aminoanthraquinone-2-carboxylic acid hydrazide are combined slowly with 10 parts of 3'-Cblophenylbenzimidchlorid in 150 parts of N-Methylpyrrolidon heated to 70 ° C and stirred for 1 hour at this temperature. One works that Reaction mixture as described under A. and contains 8 parts of that described above Oxdiazoles.

The dye dyes cotton from a reddish brown vat in red tones.

Example 2 8.4 parts of terephthaldi (3'-chlorophenylimide chloride) are introduced into a mixture, heated to 70 ° C., of 12 parts of 1-aminoanthracbinone-2-carboxylic acid hydrazide and 150 parts of N-methylpyrrolidone. The reaction mixture is first stirred for 30 minutes at 70 ° C., then heated to 120 ° C. over the course of 30 minutes and stirred at this temperature for 30 minutes. The mixture is then cooled to 60 ° C., the reaction material is filtered off with suction, washed with methanol and dried. There are 8.6 parts of the dye of the formula obtained as red crystal powder. From the red-brown vat, the dye turns cotton into a scarlet red color.

Example 3 9 parts of 1-aminoanthraquinone-2-carboxylic acid hydrazide and 11 parts of anthraquinone-2- (3'-chlorophenyl carbimide chloride) are heated together in 150 parts of N-methylpyrrolidone to 120 ° C. over the course of 1 hour. You work like in. Example 2 given, and contains 10.5 parts of the dye of the constitution as red crystal powder. The dye dyes cotton on a red-brown vat in clear red tones.

Example 4 4.2 parts of terephthaldi (3'-chlorophenylimide chloride) are added at 70 ° C. to a mixture of 7.9 parts of 1-amino-4-benzoylamino-2-carboxylic acid hydrazide and 150 parts of N-methylpyrrolidone and the mixture is heated the reaction mixture to 150 ° C within 1 hour. The mixture is then stirred for 30 minutes at 150.degree. C. and allowed to cool to 60.degree. The precipitated reaction material is now suctioned off, washed with methanol and dried. There are 4 parts of the dye of the formula obtained as blue crystal powder. The dye dyes cotton from a violet vat in strong blue tones.

Example 5 6.6 parts of 1-nitroanthraquinone-2- (methylcarbimide chloride) are introduced into a mixture, heated to 100 ° C., of 6 parts of 1-aminoanthraquinone-2-carboxylic acid hydrazide and 100 parts of N-methylpyrrohdon. The reaction mixture is then stirred at 120 ° C. for 1 hour. After the mixture has cooled down, the reaction material is suctioned off; washes it with methanol and dries it. 5.4 parts of the compound of the formula are obtained in the form of a red crystal powder. The dye dyes cotton from a reddish brown vat a strong red; its nitro group is reduced to an amino group in the vat.

Example 6 13.5 parts of anthraquinone-2-carboxylic acid (3-chloroanilide) in 75 parts of toluene with 9 parts of phosphorus pentachloride are heated to boiling for 2 hours with reflux cooling. The clear solution is now reduced to about two thirds of its original volume. Thereafter, 70 parts of N-methylpyrrolidone and 9 parts of 1-aminoanthraquinone-2-carboxylic acid hydrazide are added to the reaction mixture at 100.degree. C., the temperature of the mixture is increased to 120.degree. C. over half an hour and then stirred for a further hour at this temperature. The reaction material is then filtered off with suction at 40 ° C., washed with N-methylpyrrolidone and then with methanol and dried. This gives 12 parts of a red vat dye, which is identical to the dye described in Example 3, in the form of a dark red powder.

Claims (2)

PATENT CLAIMS: 1. Process for the production of vat dyes of the 1,3,4-oxdiazole series, characterized in that N-substituted imide chlorides can act on monohydrazides of 1-aminoanthraquinone-2-carboxylic acids. 2. Procedure according to claim 1, characterized in that the reaction with N-substituted Imide chlorides made directly in the reaction mixture by treatment of acylated alkyl or aryl amines with halogenating agents.