DE1544360C - Process for the preparation of heterocyclic disazo dyes - Google Patents

Description

The present invention relates to a process for the preparation of heterocyclic disazo dyes, those as color salts of the general formula

A-N = N-B N = N

correspond, in which A is a phenyl or naphthyl radical, which may optionally be substituted by halogen atoms, alkyl, acyl, nitro, acylamino, carboxyl, cyano, sulfone and / or sulfonamide groups, 'B a phenylene or Naphthylene radical, which can optionally be substituted by halogen atoms, alkyl, acyl, nitro, acylamino, carboxyl, cyano, sulfone, hydroxyl and / or sulfonamide groups, A being the radical of a diazo component and B the radical of a further diazotizable coupling component, R is alkyl radicals with 1 to 4 carbon atoms, R ₁ and / or R ₂ hydrogen atoms, optionally substituted alkyl radicals with 1 to 4 carbon atoms or aralkyl radicals, X and Y hydrogen atoms, optionally substituted alkyl or aryl radicals, where X and Y form a hydroaromatic ring can be linked, Z anions of simple or complex inorganic or organic acids and η denotes the numbers 1 to 4, and in which the group, RO - to the aromatic rings of the Residues A and / or B is bonded.

Of these, those dyes of the formula I are preferred in which R ₁ and R _{2 are} aralkyl or alkyl, in particular methyl, radicals.

The new dyes are obtained by using diazo compounds of amines of the formula

40

(ro),

NH, II

in which A, B, R and η have the meaning given above, couples with imidazole or its derivatives substituted in the 4- and / or 5-position and, if desired, the coupling products with alkylating agents. treated.

The aminoazo compounds II used for further diazotization are obtained in a customary manner by coupling diazo compounds of amines A - NH _{2 with amines B - NH 2 which} are unsubstituted in the p-position.

Examples of the diazo components A - NH ₂ are:

a) 2-, 3- or 4-methoxyaniline, 4-ethoxyaniline, 2-methoxyaniline-4-ethylsulfone, 2-ethoxyaniline-5-sulfonic acid diethylamide, 2-methoxy-4-acetylaminoaniline, 2-methoxy-5-methoxycarbaminoaniline, 2,5 - diethoxy - 4 - benzoylaminoaniline, 4 - chloro - 2,5 - dimethoxyaniline, 5 - nitro - 2,4 - dimethoxyaniline;

b) aniline, 1- or 2-aminonaphthalene, 2-, 3- or 4-Aminobenzoesüure, 4-CyananiIin, _4-N-1 N Dimethylglycylaminoanilin, 3- or 4-aminobenzene sulfonic acid amide, 2-, 3- or 4-ChloraniIin, 4 - bromoaniline, 2,5 - dichloroaniline, 4 - acetylaminoaniline.

Examples of door coupling components B - NH ₂ are:

c) Coupling components for the diazo compounds of groups a) and b): 3-hydroxyaniline, 3 - methoxyaniline, 3-ethoxyaniline, 5-methyl-2 - hydroxyaniline, 2 - methyl - 5 - hydroxyaniline, 2,5 - dimethoxyaniline, 2 - methoxy - 5 - methylaniline, 2-methoxy-5-chloroaniline, 2-methoxy-5-methoxycarbamino-aniline, 2-methoxy-5-propionylaminoaniline, 1 - amino - 5 - hydroxynaphthalene, 2-ethoxy-1-aminonaphthalene;

d) Coupling components for the diazo compounds of group a): 3-MethyIanilin, 2,5-Dimethylanilin, 3-acetylaminoaniline, 1-amino naphthalene.

The main coupling components are unsubstituted imidazole and 4-methyl- or 4-phenylimidazole, 4,5-dimethylimidazole, 4-methyl-5-phenylimidazole, 4,5-diphenylimidazole, 4-phenyl-5- (4'-dimethylamino) -phenylimidazole or 4,5-tetramethylene imidazole.

The coupling of the diazotized aminoazo compounds of the formula II with imidazole or his Derivatives are expediently carried out in an alkaline aqueous medium. Imidazole derivatives that are sparingly soluble in water are divided into a suitable aqueous fine division by pre-dissolving in organic solvents and / or by using dispersants brought. The hydroxides of the alkali or alkaline earth metals are preferably used as alkalis for coupling or alkali carbonates.

Under the specified coupling conditions, the disazo compounds are formed as anhydrobases the formula

= n - by - n = n - <f

III

in which A, B, X, Y, R and η have the meanings given above.

These compounds are insoluble in water and are suitable for coloring paints from an aqueous suspension, organic solvents and semi-synthetic or synthetic materials, especially from Fibers made from polyamides, polyesters, polyacrylonitrile or cellulose acetate. One can use the mentioned materials also by printing or impregnation with subsequent thermal fixation or in the Color the mass.

With mineral acids, the protonated color salts of the formula I (R ₁ = H) are obtained from the coupling products. which, however, are easily hydrolyzed again in water and therefore have only low water solubility. In contrast, readily soluble color salts are obtained by alkylating the coupling products, with “alkylation” also being understood to mean the introduction of substituted alkyl radicals or aralkyl radicals. Examples of alkylating agents are alkyl or aralkyl halides, such as methyl chloride, ethyl bromide, phenacyl chloride, dialkyl sulfates or alkyl esters of aromatic sulfonic acids, such as dimethyl sulfate, diethyl sulfate, methyl benzenesulfonate, ethyl toluenesulfonate.

The alkylation is expediently carried out in aqueous suspension or in organic solvents normal or elevated temperature. It is advantageous to work in the presence of acid-binding agents Agents such as alkali hydroxides, alkaline earth oxides, hydroxides or carbonates. Simultaneously with the Alkylation of the imidazole ring can be groups which can be substituted by excess alkylating agent Containing hydrogen atoms, such as hydroxyl, carboxylic acid or sulfonic acid amide groups, formerly changed, d. H. etherified, esterified or alkylated.

The dyestuff quaternary salts obtained by alkylation are filtered off, distilled off or Dilute with water to remove the organic solvent. They are isolated from aqueous solution by salting out and / or adding suitable acids or metal salts. The quaternary color salts are suitable as well as the coupling products for dyeing synthetic materials. In particular textile materials from polyacrylonitrile or acrylonitrile-containing copolymers are in strong, very light- and dyed wet-fast tones.

It is already known that monoazo compounds of the 2- (arylazo) -imidazole series can be converted into quaternary salts by alkylation to convert. However, these color salts only have coloristically valuable properties if they contain an alkyl or aryl-substituted amino group in the aryl radical in the p-position to the azo group. Such dyes are known from British patent specification 885 046. Without these substituents, the Dyeings on textile materials made of polyacrylonitrile are weak in color and not very lightfast. Quaternaries too Disazo dyes of imidazole with a substituted amino group in the p-position of the arylazo radical, the deep blue real colorations on polyacrylonitrile are already from the French patent 1 293 263 known. It was now surprising that disazo dyes of the imidazole, which instead of the amine radical contain one or more alkoxyl radicals in one or both of the radicals A and B, in contrast to the corresponding monoazo dyes on synthetic fibers very lightfast and wetfast, strong colors Ability to produce colorations. They also have better wash fastness than those containing amino groups Disazo dyes and do not react as strongly to different dyeing conditions. About it In addition, the dyes obtainable according to the invention enable "uniform", strongly colored and genuine ones To achieve brown tones of various shades without having to resort to dye mixtures. The parts and percentages given in the following examples are weight units. Behave parts of the room to parts by weight like the liter to the kilogram under normal conditions.

example 1

96 parts of 2-methyl-4'-methoxy-4-aminoazobenzene are added with the addition of 320 parts of 5N hydrochloric acid in a. Grind ball mill and then stirred with 4000 parts of water at room temperature. You gradually give one. Solution of 30 parts of sodium nitrite and the mixture is stirred several times Hours until the end of the diazotization. The filtered diazo solution is combined after removal of the Excess nitrite with a solution of 34 parts of imidazole in 300 parts of water and then leaves a Slowly run in a solution of 56 parts of sodium hydroxide in 80 parts of water over the course of one hour.

After coupling is complete, the filter residue is filtered off, washed with water and dried at 6O ⁰ C under reduced pressure. 32 parts of the powdered coupling product are stirred with 400 parts of chloroform, 4 parts of magnesium oxide are added and 28 parts of dimethyl sulfate are slowly added at 50 ° C. with stirring over the course of 20 minutes. The mixture is stirred for 5 hours at the boiling point, after cooling, 550 parts of benzene are added and the mixture is filtered off with suction. The dried reaction product is dissolved in 1000 parts of water with 10 parts of 10 normal hydrochloric acid. The small residue is filtered off, the dye is precipitated with 200 parts of sodium chloride, filtered off with suction and dried. The dye obtained dyes polyacrylonitrile fabric made from an acetic acid or sulfuric acid bath in full yellowish brown tones, which are very fast to light, washing and decoration.

B e i s ρ i e 1 2

In the 96 parts of 5-methoxy-2-methyl-4-aminoazobenzene according to the measures of Example 1 The filtered solution of the diazonium salt obtained is left with the solution of 31 parts of imidazole in 100 parts Gradually pour in water and then 65 parts by volume of 50% sodium hydroxide solution. The received Coupling product is filtered off with suction and washed with water. The dried dye is a brown one Powder that dissolves in dimethylformamide with a brownish yellow color and polyamide fabric in real yellowish brown Tones colors.

B e i s ρ i e I 3

32 parts of the dye obtained according to Example 2 in 5 (X) parts by volume of chloroform with addition of 5 parts of magnesium oxide and 25 parts by volume of dimethyl sulfate for several hours at 50 to 60 ^'1 C

stirred until complete implementation has occurred. This can easily be determined by paper chromatography. Then 750 parts of water and 50 parts by volume of 30% acetic acid are added and this is distilled Chloroform is removed with steam and the dye is precipitated from the hot-filtered solution by addition of 500 parts by volume of saturated sodium chloride solution. After the mixture has cooled down, the color salt becomes Sucked off, washed with a little water and dried. A red-brown powder is obtained, which is in hot water with a yellow-brown color dissolves and polyacrylonitrile fabric in brown-orange tones dyes with very good light and wet fastness properties.

Example 4

The filtered diazo solution obtained from 103 parts of 2,5-dimethoxy-4-aminoazobenzene is mixed, as described in Example 2, first with a solution of 31 parts of imidazole in 100 parts of water and then gradually with 65 parts by volume of 50% sodium hydroxide solution. The isolated and dried disazo dye is a brown powder that dissolves in 80% acetone with a yellow-brown color and dyes polyamide fibers in real brown-red shades. Polyester fabric brown colorations are obtained with very good wet fastness properties at 130 ⁰ C.

If 4'-chloro-2,5-dimethoxy-4-amirioazobenzene is used as the diazo component, thus a dye with similar properties is obtained.

Example 5

35

If 33 parts of the dye obtained according to Example 4, Paragraph 1, are obtained according to the information in Example 3 methylated, a dark brown powder is obtained which dissolves and dissolves in water with a brownish-red color Polyacrylonitrile fabrics give very good wet and lightfast brown-red dyeings.

. From the chlorine-containing coupling product obtained according to Example 4, paragraph 2, arises through Methylation a dye, the color and behavior of the chlorine-free methylation product is similar.

Example 6

103 parts of 2,5-dimethoxy-4-aminoazobenzene are diazotized as described in Example 1. the filtered diazo solution is slowly added at 0 to 5 ° C. to a solution of 96 parts of 4,5-diphenylimidazoI in 4000 parts by volume of N-methylpyrrolidone and then gradually leaves 80 parts by volume of 50% sodium hydroxide solution flow in. After the coupling has ended, the resulting dye is precipitated by adding 25 parts by volume 30% acetic acid, sucks off and washed with 60% alcohol.

The dried product is a dark brown powder that dissolves in dimethylformamide with a purple color and dyes polyamide fibers in real purple tones.

Example 7

24 parts of the dye obtained according to Example 6 are stirred in 5 (X) spaces of chloroform with 15 parts of dimethyl sulfate and 3 parts of magnesium oxide for 4 hours at 50 to 60.degree. After adding 1000 parts of water and 50 parts by volume of 30% acetic acid, the chloroform is distilled off. The crystallized after cooling dye is -abgesaugt, washed with a little water and dried at 8O ⁰ C. It dissolves in hot water with a brownish-violet color and dyes polyacrylonitrile fabrics in corinthian shades with very good light and wet fastness properties.

Example 8

111 parts of 2'-methoxy-5'-chloro-2-methyl-4-aminoazobenzene are rubbed with 160 parts by volume of 10 molar hydrochloric acid and the mixture is left for several hours stand. After adding 600 parts of water and 600 parts of ice, 120 parts by volume of 23% sodium nitrite solution are obtained added and the whole stirred for 2 hours. To the diazotization mixture thus obtained 31 parts of imidazole are gradually added, dissolved in 100 parts of water, and then 80 parts by volume of 50% strength sodium hydroxide solution added.

From the isolated and dried coupling product 35 parts with the mixture of 500 parts by volume of chloroform, 30 parts by volume of dimethyl sulfate and 6 parts of magnesium oxide for 5 hours Stirred to the boil and reflux. After cooling, it is suctioned off. The one washed with a little chloroform and dried filter cake is in the mixture of 1500 parts of water and 30 parts by volume 30% acetic acid dissolved hot and filtered. By adding 50 parts by volume, 50% zinc chloride solution and 250 parts by volume of saturated sodium chloride solution, the dye becomes a zinc chloride double salt precipitated, which is then filtered off with suction and washed with a little water.

The powder obtained after drying dissolves in hot water with a yellow color and gives up Brown-yellow colored polyacrylonitrile threads with very good light and wet fastness properties.

If 122 parts of 2 ', 4'-dimethoxy-5'-chloro-2-methyl-4-aminoazobenzoI are used as the diazo component, in this way a brown methylation product with similar coloristic properties is obtained.

Example 9

40 parts of that from 2 ', 5'-dimethoxy-4'-chloro-2,5-dimethyI-4-aminoazobenzoI and imidazole obtainable dry by the method of Example 8, paragraph 1 Coupling product are added in 500 parts by volume of chloroform with the addition of 30 parts by volume of dimethyl sulfate and 6 parts of magnesium oxide stirred for 5 hours under boiling and reflux cooling. then 4000 parts of water and 50 parts by volume of 30% acetic acid are added and the mixture is filtered hot. The filtrate becomes the dye by adding 25 parts by volume of 50% zinc chloride solution and 200 parts of sodium chloride precipitated as tetrachlorozincate. The isolated and dried product, a brown powder, dissolves in hot water with brown color and dyes polyacrylonitrile fabric in brown shades of very good Light and wet fastness.

The dyes in the table below were obtained in an analogous manner and show similar properties.

Formula of furstoflcation

Color shade on polyacrylonitrile

CH ₃ O

CH ₃ O CH ₃ O

Tan brown

Red brown brown

Red-brown red-brown red-brown

roform stirred with addition of 1 5 parts by volume of dimethyl sulfate and 3 parts of magnesium oxide as long as at 50 2,4-dimethoxy-5-chloΓbenzol-azo-4-aminonaphtha- 65-60 C until no more AusgangsfarbstofT lin (l) after the Information from Example 8 is detectable by diazo paper chromatography. After cooling down and coupled with imidazole. 20 parts of the so th, the crude product is filtered off with suction and dried. The dye obtained is dissolved in 500 parts by volume of ChIo- It is then stirred with the mixture of 50 parts

109 623/280

Example 10

Water and 10 parts of 30% acetic acid, filtered off and washed with a little water. The dried one The dark brown product dissolves in hot water with a brownish-violet color and stains polyacrylonitrile fabrics in real corinth-colored tones.

Dyes with similar properties are obtained when using 2,4-dimethoxybenzene-azo-4-aminonaphthalene- ( 1) or Z-methoxy-S-chlorobenzolazo-4-aminonaphthalene- ( 1).

Example 11

8 parts of the coupling product from 4'-nitro-5-methoxy-2-methyl-4-aminoazobenzene and imidazole are in a mixture of 150 parts by volume of chloroform, 7.5 parts by volume of dimethyl sulfate and 1.5 parts of magnesium oxide under reflux for 5 hours touched. After adding 4000 parts of water

and 30 parts by volume of 30% acetic acid, the chloroform is distilled off and the aqueous dye solution is filtered hot. Since the dye here anfallt in a hardly filterable zähfiüssig streak-forming consistency is diluted with water to the whole area 30000 parts and is part of sodium chloride at 90 to 100 ⁰ C to. After cooling, the mixture is filtered off and dried at 80 ⁰ C. The brown powder thus obtained dissolves in much hot water with yellow-brown color and are on poly acrylonitrile brown colorations of excellent fastness properties.

Claims (2)

Patent claims: 1. Process for the preparation of heterocyclic disazo dyes, which are used as color salts of the general formula ^f RO A-N = N-B in which A is a phenyl or naphthyl radical, which can optionally be substituted by halogen atoms, alkyl, acyl, nitro, acylamino, carboxyl, cyano, sulfone and / or sulfonamide groups, B a phenylene or naphthylene radical which can optionally be substituted by halogen atoms, alkyl, acyl, nitro, acylamino, carboxyl, cyano, sulfonic, hydroxyl and / or sulfonamide groups, A being the remainder of a diazo component and B the remainder of a further diazotizable one Coupling component, R is alkyl radicals with 1 to 4 carbon atoms, R ₁ and / or R ₂ hydrogen atoms, optionally substituted alkyl radicals with 1 to 4 carbon atoms or aralkyl radicals, X and Y hydrogen atoms, optionally substituted alkyl or aryl radicals, where X and Y form a hydroaromatic Ring can be linked, Z anions of simple or complex inorganic or organic acids and η the numbers 1 to 4 means, and in which the group RO— is bound to the aromatic rings of the radicals A and / or B, characterized in that diazo compounds of amines of the formula / ¹ T AN = N- NH ₇ II in which A, B, R and η have the meaning given above, couples with imidazole or its derivatives substituted in the 4- and / or 5-position and, if desired, treats the coupling products with alkylating agents. 2. The method according to claim 1, characterized in that the anhydrobases of color salts of the general formula I in which R ₁ and / or R _{2 are} hydrogen, alkylated in the presence of acid-binding agents with excess dimethyl sulfate.