DE1113276B - Process for the production of colored condensation products - Google Patents

Description

Process for the production of colored condensation products Addition to patent 1098126 The invention relates to an improved production process for the colored condensation products described in patent 1098 126 using new and technically easily accessible starting materials.

The subject of the patent is a process for the production of valuable yellow, orange to red pigments, which, for example, by their color strength, their heat resistance, their lightfastness and their fastness to sublimation the colored polyplasts produced therewith are excellent. These dyes are obtained by condensation of a polyprimary amino compound with that of the amino groups equivalent Amount of the same or different isoindolin-1-ones, which are slightly in the 3-position Contain exchangeable substituents which claim two bonds in terms of type or number and are more mobile than doubly bonded oxygen, or corresponding isoindolenines with simultaneous hydrolysis by adding such isoindolin-l-ones or isoindolenines used, which are tetrahalogenated in the benzene residue.

It has now been found that azomethine dyes of the tetrahalo-isoindolinone series can be used of great purity and in good yields, if you use them as starting materials the technically easily accessible 2-cyanobenzoic acid esters are used. The new procedure is characterized in that one has four halogen substituents in the benzene nucleus containing 2-cyanobenzoic acid ester with ammonia or primary amine to form 3-iminoisoindolin-1-one and this with the equivalent amount of a polyprimary amino compound condensed to the corresponding azomethine dye.

The tetrahalogeno-2-cyanobenzoic acid esters used as starting materials derive from monovalent or polyvalent aliphatic, araliphatic or cycloaliphatic Alcohols. Well usable are z. B: the benzyl esters, one serves with advantage however, the esters of monohydric low molecular weight alcohols, especially those with a maximum of 5 carbon atoms. Those in the benzene nucleus are particularly important from a technical point of view 2-Cyanobenzoic acid methyl and ethyl ester containing 4 chlorine atoms.

2-Cyanobenzoic acid esters which can be used according to the invention are obtained, for example from halogenated 3; 3-dichlorophthalides by reaction with ammonia to o-cyanobenzoic acids Ammonium salts and esterification.

The esterification of tetrachloro-o-cyanobenzoic acid can, for. B. by Treatment of the corresponding silver, alkali or alkaline earth salts with esters of Hydrogen halides, sulfuric acid or aromatic sulfonic acids with lower Alcohols are run. 3,3-dichlorophthalide are made from phthalic anhydrides and phosphorus pentachloride easily available.

The implementation of the 2-cyanobenzoic acid ester with ammonia or primary Amines can be in aqueous solution or suspension as well as in inert organic Solvents or diluents and should be carried out at the lowest possible temperatures, preferably at room temperature. Ammonia is used for this or amine with advantage in excess. Depending on the reactivity of the amines can also a higher reaction temperature may be indicated, especially in the absence of Solvents.

The primary amines are those of the aliphatic, cycloaliphatic, araliphatic and aromatic series into consideration, especially monoamines, such as z. B. butylamine, amylamine, hexylamine, octylamine, cyclohexylamine, benzylamine, aniline, Toluidines and chloroanilines. Finally, alkali metal amides can also be used will; lithium amide and sodium amide in particular come into consideration. Preferred The reactant is ammonia.

As a solvent and diluent, their presence when reacting the 2-cyanobenzoic acid ester with ammonia or amines if necessary is advantageous, z. B. alcohols and ethers, such as methanol, ethanol, butanol, Ethylene glycol and its methyl and ethyl ethers, cyclohexanol, benzyl alcohol and Dioxane, or hydrocarbons such as ligroin, cyclohexane, tetra- and decahydronaphthalene or halogen and nitro hydrocarbons, such as chloroform, tetrachlorethylene, dichlorobenzene, Nitrobenzene and nitrotoluenes, in question.

The condensation of the tetrahalogen-3-iminoisoindolin-1-ones obtainable according to the present invention with the polyprimary amino compounds takes place according to methods as already described in patent 1098126 and illustrated several times by examples. The polyamines which can be used for condensation are those described in patent 1098 126, namely preferably aromatic polyamines of the benzene, naphthalene, diphenyl and stilbene series, which preferably contain the amino groups in positions which are linked by a chain of conjugated double bonds. Finally, the properties and possible uses of the colored condensation products obtained according to the invention have also been discussed in detail in the patent mentioned.

From the USA: Patent 2,537,352, the condensation of polyprimary amines with 2-cyanobenzoic acid amide for the production of azomethine dyes of the isoindolinone series is known. However, the dyes described in this patent contain a maximum of 2 halogen atoms per benzene residue of the isoindohnone rings; moreover, more highly halogenated cyanobenzoic acid amide is not accessible. In comparison with the condensation product of dichloro-3-iminophthalimide and benzidine known from this patent, the comparable condensation product of 3-imino-4,5,6,7-tetrachloroisoindolin-1-one and benzidine obtainable according to the invention shows better lightfastness. Compared to the 1-phenylamino-3-phenylimino-4,5,6,7-tetrachloroisoindolenine known from German patent specification 906935, the condensation product of 3-imino-4,5,6,7-tetrachloroisoindoline-1 obtainable according to the invention has -one and 1,4-diaminobenzene have better fastness to overcoating.

Details can be seen from the following examples. In these Unless expressly stated otherwise, examples mean the parts Parts by weight; they are related to parts by volume as the kilogram is to the liter.

EXAMPLE 1 A solution of 45 parts of 3,4,5,6-tetrachloro-2-cyanobenzoic acid methyl ester in 400 parts of methyl alcohol is saturated with gaseous ammonia at room temperature and the mixture is stirred for 20 hours. The yellowish precipitate which has separated out is filtered off with suction and washed with water and alcohol. 40 parts of a pale yellowish product are obtained which melts at about 300 ° C. with decomposition. The elemental analysis is correct for 3-imino-4,5,6,7-tetrachloro-isoindolin-1-one.

14.2 parts of this compound are combined with 6.5 parts of 4,4'-diaminodiphenyl chlorohydrate heated to 150 ° C. in 150 parts of nitrobenzene for 1 hour. The resulting orange Precipitate is filtered off with suction while hot, washed with alcohol and water and dried. 17 parts of a pure, orange-colored pigment dye are obtained, which colored polyplasts of excellent lightfastness. The colorations are fast to migration.

The 3,4,5,6-tetrachloro-2-cyanobenzoic acid methyl ester can also with aqueous-alcoholic ammonia or with liquid ammonia at room temperature in the 3-irnino-4,5,6,7-tetrachloroisoindolin-1-one can be converted.

The methyl 3,4,5,6-tetrachloro-2-cyanobenzoate used as starting material (Melting point 83 to 84 ° C) can, for. B. be made as follows: Asymmetrical 4,5,6,7-tetrachloro-3,3-phthalyl chloride is reacted with aqueous ammonia, whereby the ammonium salt of 3,4,5,6-tetrachloro-2-cyanobenzoic acid is formed. With barium chloride the ammonium salt is converted in aqueous solution into the barium salt and this in very good yield with methyl sulfate in the 3,4,5,6-tetrachloro-2-cyanobenzoic acid methyl ester convicted. Example 2 A solution of 3.8 parts of benzyl 3,4,5,6-tetrachloro-2-cyanobenzoate 100 parts of concentrated ammonia are added in 200 parts of methanol and the mixture was stirred for 40 hours at room temperature. 2.5 parts are obtained of the 3-imino-4,5,6,7-tetrachloro-isoindolin-1-one already described in Example 1.

7.1 parts of the compound thus prepared are mixed with 1.35 parts of 1,4-diaminobenzene heated in 40 parts of naphthalene at 180 to 200 ° C for 2 hours. The yellow colored reaction mixture is cooled to 150 ° C, diluted with 100 parts of hot nitrobenzene and filtered hot. The residue is washed with nitrobenzene, alcohol and acetone. It will be 5.6 Parts of an orange-yellow, strongly colored pigment obtained, which is in polyplasts characterized by excellent light and migration fastness. The one used here Benzyl 3,4,5,6-tetrachloro-2-cyanobenzoate (melting point 105 to 107 ° C) can be prepared in the following way: The ammonium salt described in Example 1 the 3,4,5,6-tetrachloro-2-cyanobenzoic acid is converted into the silver salt with silver nitrate transferred and this by treatment with benzyl iodide in good yield in the corresponding benzyl ester converted. Example 3 15 parts 3,4,5,6-tetrachlor - 2 - cyanobenzoic acid methyl ester are dissolved in 300 parts of methanol and diluted with 50 Parts of n-butylamine are added. The solution is stirred at room temperature for 40 hours, a yellowish precipitate separates out. The reaction product is divided into 500 parts Given water and the precipitated product filtered off. To. recrystallization from alcohol, 3-butylimino-4,5,6,7-tetrachloro-isoindohn-1-one is obtained as a yellowish, crystalline substance Melting point 115 to 118 ° C.

6, 8 parts of the product thus obtained and 1.2 parts of 2,6-diaminotoluene are heated in 150 parts of glacial acetic acid for 2 hours under Rüökfluss. There arises a pure, yellow pigment, which is filtered off hot and washed with glacial acetic acid, Alcohol and acetone is cleaned. It has excellent light and migration fastness in polyplasts stained with it. Example 4 10 parts of 3,4,5,6-tetrachloro-2-cyanobenzoic acid methyl ester are with 50 parts of aniline for 6 hours 150 ° C heated. The received Alcohol is added to the solution, whereupon the 3-phenylimino-4,5,6,7-tetrachloro-isoindolin-1-one precipitates as a yellow substance (melting point 260 to 262 ° C).

9 parts of this compound are combined with 2.3 parts of 4,4'-diaminodiphenyl refluxed in 200 parts of glacial acetic acid for 2 hours. It is filtered hot from the Separated off, the precipitate washes with glacial acetic acid, alcohol and acetone and obtained after drying 7.5 parts of an orange pigment, which with that of Example 1 is identical.

Claims (2)

PATENT CLAIMS: 1. Further development of the manufacturing process of colored condensation products according to patent 1098126, characterized that one contains a 2-cyanobenzoic acid ester containing four halogen substituents in the benzene nucleus with ammonia or primary amines and the 3-iminoisoindolin-l-one obtained condensed with the equivalent amount of a polyprimary amino compound. 2. Procedure according to claim 1, characterized in that the 3-iminoisoindolin-l-one is used by reacting 3,4,5,6-tetrachloro-2-cyanobenzoic acid methyl or ethyl ester product obtainable with ammonia is used. Considered publications: German Patent No. 906 935; U.S. Patent No. 2,537,352. At the notice A coloring table has been laid out for the application.