DE1911304A1 - 3-arylazo-4,5-dihalo-6-pyridazones useful as dyeintermediat - as dye intermediates - Google Patents

Abstract

3-Arylazo-4,5-dihalo-6-pyridazones useful as dye intermediates Title cpds. of formula (I) (where X and Y are halogen, R1 is a (cyclo)aliphatic, araliphatic or aromatic residue and R2 is an aromatic residue) are prepd. by reacting hydrazones of the formula HOOC-CY=CX-CH=N-NHR1 (II) with R2- =N Z- (where Z is the anion of an acid). (I) can e.g. be reacted with arylamines to give dyes suitable for imparting pastel shades to polyamide fibres. In an example, mucochloric acid in DMF is treated at 0 degrees with PhNHNH2 to give a (II)-contng. soln. which is stirred 2 hrs. at 0 degree then 2 hrs. at 30-40 degrees with a diazonium soln. prepd. from PhNH2 in HCl and NaNO2 to yield (I; R1=R2=Ph, X=Y=Cl), m.p. 222 degrees C.

Description

Process for the preparation of 3-aryl-azo-4,5-dihaloEenpyridazonen- (6) The invention relates to a process for the preparation of 3-arylazo-4,5-dihalogenpyridazonen- (6) by reacting the hydrazones of mucohalogenic acids with diazonium salts.

It is from Houben-Weyl, Methods of Organic Chemistry, Volume X / 3, Pages 631 ff. Known that hydrazones of aldehydes with diazonium compounds Formazans are implemented. A corresponding conversion to pyridazones or a Ring closure of formazans to such substances are not known. It is also so far not successful, pyridazones unsubstituted in the 3-position with diazonium salts to convert to 3-aryl-azo compounds.

It has now been found that 3-aryl-azo-4,5-dihalogenpyridazone- (6) of the general formula where X and Y can be the same or different and each represent a halogen atom, R1 denotes an aliphatic, cycloaliphatic, araliphatic or aromatic radical and R2 stands for an aromatic radical, advantageously when hydrazones of mucohalogenic acids of the general formula are prepared in which X, Y and R1 have the aforementioned meaning, with diazonium salts of the general formula in which R2 has the aforementioned meaning and Z denotes the anion of an acid, is reacted in the presence of an organic solvent.

In the case of using mucochloric acid phenylhydrazone and phenyldiazonium chloride, the reaction can be represented by the following formulas: In view of the prior art, the process according to the invention surprisingly gives a large number of 3-aryl-azo-4,5-dihalogenpyridazonen- (6) in a simple manner in good yield and purity.

Preferred hydrazones of mucohalogenic acids of the general formula II and accordingly preferred end products I are those in whose formulas X and Y can be the same or different and each represents a chlorine atom or a bromine atom R 1 is an alkyl radical, in particular having 1 to 7 carbon atoms Cycloalkyl radical, in particular with 5 to 10 carbon atoms, an aralkyl radical, in particular with 7 to 10 carbon atoms, an aryl radical, in particular one Denotes phenyl radical. The remainders mentioned can still be trundled through one or more groups and / or atoms which are inert to the reaction conditions, e.g. B. nitro groups, chlorine, Bromatoine be substituted. Instead of the starting materials II, these can also be used substances forming during the reaction, e.g. B. a mixture of the corresponding mucohalogenic acids and hydrazines can be used.

There come z. B. the following hydrazones of mucohalogenic acids as starting materials II under consideration: phenyl-, n-butyl-, p-chlorophenyl-, o-nitrophenyl-, m-nitro-p-chlorophenyl- Isobutyl, o, p-dichlorophenyl, cyclohexyl, benzyl, o-bromocyclohexyl hydrazone of Mucochlor, Muc ob rom, Muco-monochlor-monobromic acid.

Aromatic diazonium salts are used as further starting materials of appropriate inorganic acids of the general formula III. Preferred starting materials III and correspondingly preferred end products I are those in whose formulas R2 stands for an aryl radical, in particular with 6 to 10 carbon atoms, which still by one or more of the aforementioned, inert under the reaction conditions Groups and / or atoms can be substituted, and Z is the anion of an inorganic Called acid.

As anions, for. B. the bromide, perchlorate, hydrogen sulfate, Nitrate, rhodanide, phosphate, fluoborate, hydrogen carbonate and especially that Sulphate and chloride anions in question. Optionally, organic salts can also be used Acids, e.g. B. acetic acid, depending on the choice of jiazonium component used will. Starting material II is generally in a molar ratio with starting material III from 1 to 10, in particular 1 to 2 mol per 1 mol of starting material II reacted. as Starting materials III are z. B. suitable the benzene, o-toluene, p-toluene, p-xylene, o-chlorobenzene, m-chlorobenzene, p-nitrobenzene, ß- or M -naphthalene-diazonium chlorides and corresponding compounds with the aforementioned anions.

The diazonium compound can by all known methods in which Usually by reacting the aromatic amino compound with acid and sodium nitrite in the presence of water and ice. Regarding the embodiments the diazotization is on Ullmann's Encyclopedia of Industrial Chemistry, Volume 5, Pages 786 ff. Referenced.

The reaction is usually carried out at a temperature between -20 and + 500C, preferably between -20 and + 100C, without pressure or under pressure, continuously or carried out batchwise.

One used in the reaction under the reaction conditions inert, organic solvent and optionally water as the solution medium of the Diazonium salt. As organic solvents, for. B. Consider: Tertiary Amines, e.g. B. pyridine, triethylamine, dimethylaminoethanol, disubstituted on the nitrogen atom Carboxamides, e.g. B. dimethylformamide; Chlorinated hydrocarbons such as chloroform, Methylene chloride, perchlorethylene, aromatic hydrocarbons such as benzene, nitrobenzene, Toluene, xylene, diisopropylbenzene, tetralin. The organic solvent is used in Usually in an amount of 100 to 2,000% by weight based on starting material II.

The reaction can be carried out as follows: A mixture of the Starting materials II and III, together with the organic solvent, is during Maintained at the reaction temperature for 1 to 4 hours. The mixture is expediently kept at low temperatures e.g.

between -20 and + 10 ° C, and increases the temperature towards the end of the reaction, z. B. up to 40 to 50 ° C. The end product is then made from the mixture in the usual way, z. B. by filtration and recrystallization from benzene, n-butanol ethanol acetonitrile or ethyl acetate, separated Instead of the hydrazone II, a mixture can also be used first the corresponding mucohalic acid and the hydrazine in one of the above organic solvent to the reaction temperature z. B. -20 to + 100C, brought will. Without isolating the hydrazone II formed, the mixture becomes the Starting material III is added, and the reaction is now back to the one described Way done.

The starting material III can undergo the reaction in the dry state, in the organic Solution, e.g. B. in one of the solvents mentioned, or expediently in the aqueous, acidic solution to be supplied to its production.

The new compounds which can be prepared by the method of the invention are in dungen are valuable starting materials for the production of dyes. So can out them z. B. can be obtained by reacting with substituted arylamines dyes those in an amount of 0.2 to 5% by weight, based on the weighted amount of fiber material, Polyamide fibers in aqueous suspension at 90 to 1000C or according to other known ones Dyeing process for disperse dyes dye and waterfast, pastel-colored Color tones result.

In particular, preferred end products I of the process, in addition to in the examples mentioned, 3-phenyl-, 3-o-toluyl-, 3-p-toluyl-, 3-p-xylyl-, 3-o (m, p) -chlorophenyl-, 3-o (m, p) -nitrophenyl-azo-4,5-dichloro -1-phenyl-pyridazine- (6); appropriate 1-chlorohexyl-, 1-n-butyl-, 1-p-chlorophenyl-, 1-o-nitrophenyl-, 1-m-nitro-p-chloro-phenyl-, l-isobutyl compounds; analogous 4,5 dibromo derivatives.

The parts given in the examples are parts by weight.

Example 1 in a stirred apparatus become a solution of 34 parts Mucochloric acid in 500 parts of dimethylformamide at 0 ° C. 22 parts of phenylhydrazine Stirring added. The yellow colored solution becomes a diazonium salt solution slowly fed, which consists of 19 parts of aniline in a hydrochloric acid solution with sodium nitrite in known Way is made. The mixture is stirred at OOC for 2 hours, then heated 2 hours at 30 - 400C and vacuum. 57 parts of end product are obtained after recrystallization from benzene 53 parts (73.6% of theory) 3-phenyl azo-4,5 dichloro-1-phenyl-pyridazine- (6) with a melting point of 222 ° C.

Concentration of the dimethylformamide filtrate gives a further 7 Parts of raw end product.

Calc .: C 55.7 H 2.9 0 4.64 N 16.2 Cl 20.6 found: 56.1 3.0 5.1 16.2 19.8 Example 2 A solution of 51.6 parts of mucobromic acid is added to a stirred apparatus 22 parts of phenylhydrazine in 500 parts of pyridine were added at -10 ° C. with stirring. After about 1/2 hour, the solution becomes a mixture of 22 parts of aniline with sodium nitrite Diazonium salt solution prepared in hydrochloric acid solution is slowly added to the mixture is now stirred for 2 hours and then heated to 20 ° C for 3 hours.

25 parts of precipitated crystalline solid are filtered off with suction and recrystallized from n-butanol. 32 parts are obtained (37.3% the Theory) 3-Phenyl-azo-4,5-dibromo-1-phenyl-pyridazine, mp 205-206 ° C.

Calc .: C 44.3 H 2.3 0 3.7 N 12.9 Br 36.9 found: 44.9 2.7 3.9 12.7 35.9 Example 3 In a stirred apparatus, a solution of 26 parts of phenylhydrazone is added of mucochloric acid in 500 parts of pyridine which was prepared from 14 parts of p-nitroaniline Diazonium salt solution slowly added at 0 ° The mixture is then stirred for 5 hours, then heated to 500C, decanted from the crystalline precipitate formed and acidified with dilute hydrochloric acid. The precipitate is boiled with ethanol extracted, the alcoholic solution is then concentrated. The end product crystallizes after the solution has cooled down. 13 parts (33.3% of theory) of 3-p-nitrophenylazo-4,5-dichloro-1-phenyl-pyridazon- (6) are obtained from mp 98 to 1020C (decomposition) calc .: C 49.3 H 2.32 O 12.3 N 17.9 Cl 18.2 found: 50.3 2.6 13.6 17.2 17.2 Example 4 A solution of 34 parts of mucochloric acid in 500 parts of dimethylformamide at 00C 22 parts of phenylhydrazine and then a diazonium solution of 26 parts of p-chloroaniline was added with stirring. The mixture is stirred for 1 hour at room temperature on a mixture of ice and hydrochloric acid given and suctioned off. The filter material is recrystallized from acetonitrile. 39 parts (48.3% of theory) of 3-p-chlorophenyl-azo-4,5-dichloro-1-phenyl-pyridazine- (6) are obtained from m.p. 211 to 213 ° C.

Example 5 The reaction is similar to Example 1 with 24 parts of cyclohexylhydrazine carried out instead of phenylhydrazine 63.7 parts are obtained (85n5% of theory) 3-Phenyl-azo-495-dichloro-cyclohexyl-pyridazon- (6), mp 165-166 ° C.

Calc .: C 54.8 H 4.3 0 4.6 N 16.0 Cl 20.3 found: 54.6 4.8 4.5 16.0 19.8 Example 6 A solution of 12 parts of n-butylhydrazone is added in a stirred apparatus of mucochloric acid in 150 parts of dimethylformamide at 0 ° C, a diazonium salt solution from 4.7 parts of aniline added slowly. Then the implementation is analogous to Example 1 carried out.

11.7 parts (71.5% of theory) of 3-phenyl-azo-4,5-dichloro-1-n-buthyl-pyridazon- (6) are obtained of melting point 67 ° -68 ° C. (recrystallized from ethanol).

Calc .: C 51.8 H 4.3 0 4.9 N 17.2 Cl 2199 found: 51.6 4.1 6.7 17 21.2 Example 7 A solution of 17 parts of mucochloric acid is added to a stirred apparatus and 14.5 parts of p-chlorophenylhydrazine in 150 parts of dimethylformamide at 0 ° C. Stirring a diazonium solution of 13 parts of p-chloroaniline slowly added. The mixture is stirred for 1/2 hour at 0 ° C and then warmed to 50 ° C. The here formed, crystalline precipitate is recrystallized from ethyl acetate.

9.5 parts (28.8% of theory) of 3-p-chlorophenyl-azo-4,5-dichloro-1-p-chlorophenyl-pyridazon- (6) are obtained from m.p. 227 to 2280C.

Calc .: C 45.8 H 1.92 0 4.82 N 13.4 Cl 33.9 found: 46.9 2.4, 2 12.9 33.1 example 8 In a stirring apparatus, a solution of 17 parts of mucochloric acid and 5 Parts of methylhydrazine in 200 parts of dimethylformamide at 0 ° C. with stirring, a diazonium chloride solution slowly added from 9.3 parts of aniline. The mixture is stirred at 0 ° C. for 1/2 hour and then heated to 50 ° C. The crystalline precipitate formed in this way is precipitated Cyclohexane recrystallized.

12.5 parts (44.2% of theory) of 3-phenylazo-4,5-dichloro-1-methyl-pyridazon- (6) are obtained of m.p. 134-135 ° C.

Calc .: C 46.7 H 2.83 O 5.55 N 19.8 Cl 25.1 found: 47.2 2.7 6.0 19.6 25.1 Example 9 Mucochloric acid is added to a solution of 14 parts in a stirred apparatus and 9 parts of m-tolylhydrazine in 200 parts of dimethylformamide at 0 ° C. with stirring a diazonium chloride solution of 7.5 parts of aniline was slowly added. The mixture is stirred for 1/2 hour at 80C and then heated to 50 ° C. The resulting crystalline precipitate is recrystallized from acetonitrile.

5 parts (18.1% of theory) of 3-phenylazo-4> 5-dichloro-1-m-tolyl-pyridazon- (6) are obtained of m.p. 186-187 ° C.

Calc .: C 57.8 H 3.34 O 4.46 N 15.6 Cl 19.8 Found: 58.1 3.2 4.5 15.4 19.4

Claims (1)

Claims 1) Process for the preparation of 3-aryl-azo-4,5-dihalogenpyridazones- (6) of the general formula where X and Y can be identical or different and each represent a halogen atom, R1 denotes an aliphatic, cycloaliphatic, araliphatic or an aromatic radical and R2 stands for an aromatic radical, characterized in that hydrazones of mucohalogenic acids of the general formula in which X, Y and R1 have the aforementioned meaning, with diazonium salts of the general formula in which R2 has the aforementioned meaning and Z denotes the anion of an acid, in the presence of an organic solvent converts 2 # 3-arylazo-4,5-dihalogenpyridazone- (6) of the general formula where X and Y can be identical or different and each represent a chlorine atom or a bromate, R1 denotes an alkyl, cycloalkyl, aryl radical or an aryl radical substituted by one or more nitro groups, chlorine atoms, bromine atoms and / or alkyl groups having 1 to 4 carbon atoms and R2 represents an aryl radical or an aryl radical substituted by one or more nitro groups, chlorine atoms, bromine atoms and / or alkyl groups having 1 to 4 carbon atoms.