DE603622C - Process for the preparation of condensation products of the aromatic series - Google Patents

Description

Process for the preparation of condensation products of the aromatic series It has been found that aromatic nitro and nitroso compounds which contain a halogen or hydrogen atom in the p-position and [or in at least one o-position to a nitro or nitroso group condense in the presence of alkaline condensing agents with compounds which contain at least one methyl or methylene group belonging to an activating group such as -CO -CH " -CO-C, H" -CO-NH-, -CN, -COOC.HS, is adjacent. The activating group can also be linked to the methylene group to form a ring, e.g. B. in succinimide, cyclohexanone or in the ketotetrahydronaphthalenes. As alkaline condensing agents, for. B. possible: potassium hydroxide, sodium hydroxide, sodium amide, sodium sulfide. (The condensation can be carried out in an aqueous or organic medium, e.g. in benzene, chlorobenzene, pyridine, alcohols, or even without a diluent, e.g. in an excess of one of the reaction components when working with the equivalent amounts of the reaction components, the reaction occurs.The temperature can vary within wide limits depending on the reaction components used. B. at the boiling point of the diluent used, must be carried out.

Analyzes and reactions of the products obtained make it probable that they arise in the simplest case by adding a molecule of the reactive methylene compound to a molecule of the nitro or nitroso compound with simultaneous or subsequent elimination of hydrogen or hydrogen halide. The released hydrogen can under certain circumstances, especially when excluding hydrogen-absorbing substances, e.g. B. in a nitrogen atmosphere, the nitro or. Partly reduce the nitroso group, so that in addition to compounds of the general formula Where x denotes hydrogen or a substituent, products that are lower in oxygen or richer in hydrogen can also form. If you work in the presence of air, the reduction of the nitro or nitroso group can, under certain circumstances, be stopped. So z. B. in the condensation of p-nitrochlorobenzene with benzyl cyanide in the presence of potassium = hydroxide in pyridine in a nitrogen atmosphere a deep blue colored solution or suspension, which should contain the potassium salt of azi-p-nitrodiphenylacetonitrile, because by treating this potassium compound with acids one is a halogen-free compound which crystallizes in colorless prisms and which, according to the analysis, is a nitrodiphenylacebonitrile. The reaction probably proceeds according to the following equation: If, on the other hand, nitrobenzene is condensed with benzyl cyanide under the same conditions, a deep blue liquid is also formed, from which, in addition to the above-mentioned nitrodiphenylacetonitrile, a product which crystallizes in golden yellow prisms is obtained. After analysis and properties of the compounds, a reduction product of the nitro body mentioned, namely p-hydroxylaminodiphenylacetonitrl., Is present. The reaction probably proceeds according to the following equation: Under certain circumstances, several molecules of one component can also take part in the condensation; in addition, the primary reaction product can secondary further changes, e.g. B. saponification of carboxalkyl groups and the like., Suffer. So you get z. B. by treating a mixture of o-nitrochlorobenzene and ethyl acetate with finely divided potassium hydroxide in boiling benzene, a product which, according to analysis and properties, is 4 # 4'-dinitro-3 '3'-dichlorodiphenylacetic acid.

The products obtained can be used as dyes or dye intermediates Find use.

Example i In a mixture of 10 parts of 4-chloronitrobenzene, 42 parts a paste made by grinding equal parts of potassium hydroxide and technical Pyridine was obtained in the ball mill, and 100 parts of technical grade pyridine (pyridine base mixture from bp. i 2o to i40 °), which is cooled to -5 °, become 7.5 within 10 minutes Parts of benzyl cyanide entered and the mixture with exclusion of air for 3'12 hours stirred at about 0 °. The reaction mass turns blue-violet. One dilutes with Benzene, sucks off, washes with benzene, ether, finally with cold water. The remaining one Residue and that obtained from the aqueous filtrate by acidification with acetic acid The products are identical and, according to reactions and analysis, consist of 4-nitrodiphenylacetonitrile. The substance is easily soluble in alcohol, ether and pyridine, crystallized from ether in colorless prisms, their solutions in pyridine or alcohol change color violet on addition of caustic alkalis. You can also see the reaction in aqueous medium, e.g. B. in potassium hydroxide solution of about 5o%, at about 6o to Perform 70 °. Examples In 100 parts of the potassium hydroxide paste used in Example i, which is diluted with 150 parts of technical pyridine, is carried in a nitrogen or air flow at 2o to: 25 'a mixture of 2q., 6 parts of nitrobenzene, 23.4 Parts of benzyl cyanide and 50 parts of pyridine within 1 /. Hour and stir some time at 2o to 25 °. The reaction mass turns blue-violet: it becomes, as described in Example i, worked up.

A yellow one is obtained from the aqueous filtrate by acidification Precipitate that crystallizes from benzene in orange needles and according to properties and analysis is the 4-hydroxylaminodiphenylacetonitrile. It dissolves in dilute Caustic soda with a yellow-brown color, in alcoholic alkalis orange-red. In alcohol and ether it is less soluble than 4-nitrodiphenylacetonitrile. By ether the aqueous and concentration of the benzene filtrates is obtained in Example i 4-nitrodiphenylacetonitrile described.

Instead of potassium hydroxide, other alkaline condensing agents can also be used, z. B. sodium hydroxide or sodium amide, use. In an analogous way you can also other compounds containing an activating methylene group with nitrobenzene condense, so z. B. Cyclohexanone a condensation product, its solution in pyridine turns blue on addition of potassium hydroxide.

Example 3 A solution of 8 parts of 4-chloronitrobenzene and 6 parts Succinimide in 50 parts of technical grade pyridine is stirred at 10 ° heated suspension of 30 parts of potassium hydroxide in 23o parts of pyridine entered and cooked the mixture for a few hours. Thereupon the reaction mass becomes in abundance Poured cold water, sucked off the separated olive-brown precipitate, with Water washed and dried.

The product crystallizes from alcohol in orange-yellow needles and is easily soluble in ether, petroleum ether and pyridine.

Example 4 In a suspension of 3o parts of potassium hydroxide in 24o Parts of benzene become a solution of 15.8 parts of 2-chloronitrobenzene at the boiling point and g parts of ethyl acetate in 5o parts of benzene and the mixture kept boiling for some time. The reaction liquid turns purple at first, later red-brown. After cooling, ice and hydrochloric acid are added and the mixture is extracted the acidic liquid with benzene. Fractionation gives the benzene solution two substances.

A poorly soluble product that turns benzene into colorless flakes crystallized, easily soluble in soda solution or dilute aqueous alkalis, also in ether and alcohol, somewhat less soluble in benzene. When heated .in Dimethylaniline gives off the product carbon dioxide. According to the analysis, the substance is q. # q .'-Dinitro-3 # 3'-dichlorodiphenylacetic acid. - '- --- - --- From the mother liquors a more soluble product crystallizes in orange needles, which does not dissolve in aqueous alkalis. Its solution in pyridine is yellow and is added on of alkali red-violet.

EXAMPLE s A solution of 17.2 parts of 2-nitrobenzoic acid and 6 parts of acetophenone in 60 parts of pyridine is added dropwise at 5 ° to 10 ° with stirring to a suspension of 30 parts of potassium hydroxide in 130 parts of pyridine. The mixture turns reddish blue in a short time. Work as in example q. indicated, and the yellow-brown precipitate crystallized from alcohol. The product dissolves easily and colorlessly in soda solution and in aqueous alkalis. It dissolves red-brown in alcoholic alkali. From diluted alcohol it crystallizes in colorless needles. According to analysis and properties, the body is likely the 4-nitrodeoxybenzoin-3-carboxylic acid.

Example 6 A mixture of 33 parts of 3-nitrobenzoic acid, 12 parts Benzyl cyanide and 50 parts of pyridine are left in a stream of air at 45 to 50 'in a suspension of 45 parts of ground sodium hydroxide in 150 parts of pyridine are poured in. The mass turns deep purple. After completion of the reaction, the reaction product becomes precipitated by stirring into a mixture of ice and hydrochloric acid, after standing for some time suctioned off and recrystallized from alcohol. So you get orange needles, which are Dissolve red-violet in aqueous alkalis, blue-violet in alcoholic alkalis. Of the According to analysis, the product has the composition of a nitrodiphenylacetonitrile carboxylic acid or an isomeric compound. From the mother liquors resulting from the crystallization A substance can be obtained by concentration which is present in aqueous soda solutions is soluble and crystallizes from quinoline in colorless needles. That The same product is obtained if 2-chloro-5-nitrobenzoic acid is used instead of 3-nitrobenzoic acid condensed with benzyl cyanide.

Example ? In a mixture of 45 parts of ground potassium hydroxide and 27o parts of pyridine becomes a solution of 40.5 parts at 15 to 20 ° with stirring 3'-Nitro-2-benzoylbenzoic acid and 15 parts of benzylcyanide in 150 parts of pyridine entered, passing a vigorous stream of air through the liquid. To Increase the temperature to 20 to 25 °, stir for some time and work then the red-violet reaction mass, as indicated in Bzbeispiel i. The reaction product crystallizes from benzene in orange needles. It dissolves easily in alcohol and pyridine; the solutions turn purple on the addition of caustic alkalis. The solution too in aqueous alkalis is purple. Instead of 3'-nitro-2-benzoylbenzoic acid, one 3'-nitro-4'-chloro-2-benzoylbenzoic acid or 3'-nitro-4'-methyl-2-benzoyl,: enzoic acid use, whereby condensation products with similar properties are obtained.

The same product arises if one takes in place of potassium hydroxide Sodium sulfide used.

Instead of benzyl cyanide, other nitriles can also be used with m-nitrobenzoylbenzoic acid condense, so z. B. Malonitrile a condensation product that is in Pyridine dissolves with a bluish red color on the addition of potassium hydroxide.

Example 8 The mixture is passed into a boiling suspension of 30 parts of ground Potassium hydroxide in Sao parts benzene a dry air stream, carries within 25 Minutes a solution of 9 parts of 2. 5-dichloronitrosobenzene and 2 parts of acetonitrile in 100 parts of benzene and keeps boiling for about 2 hours. After work-up the red reaction mass in the usual manner and recrystallization of the reaction product orange needles are obtained from diluted alcohol. The product is easily soluble in pyridine, alcohol and glacial acetic acid; the solution in pyridine changes color on addition of Alkati red-violet.

The 2 # 5-dichloronitrosobenzene is condensed using potassium hydroxide in pyridine at 15 to 20 ° with benzyl cyanide, a product is obtained which is dissolves greenish blue in pyridine in the presence of caustic potash. Example 9 In a mixture of 10 parts of 2-chloronitrobenzene, 2o parts of ground potassium hydroxide and 12o parts Pyridine are at 0 to 5 ° 7.5 parts of benzyl cyanide dissolved in 2o parts of pyridine, stirred in. The red-violet reaction mixture is stirred for some time and then diluted with benzene, filtered off with suction and worked up according to example i. The thus obtained Condensation product crystallizes from dilute alcohol in yellow needles and is the analysis according to a chloronitrodiphenylacetonitrile. It is easily soluble in Pyridine and glacial acetic acid, heavier in benzene and alcohol. Its solution in pyridine stains turns violet-red with the addition of caustic alkali.

Example 10 In a solution of 7 parts of nitraniline and 6 parts Benzyl cyanide in 40 parts of pyridine are stirred at 0 ° while passing one through dry air stream 18 parts of a potassium hydroxide by grinding equal parts and benzene-made paste, diluted with 35 parts of pyridine and cooled to 0 °, gradually entered. After the end of the introduction, the mixture is stirred at 0 ° for 2 hours and then worked up as described in Example i. You get an orange-red Condensation product made from diluted alcohol in red prisms with a green surface luster crystallized. It dissolves in pyridine with an orange-red color upon the addition of Potassium hydroxide turns red-violet. On acetate silk it produces orange colors.

Example ii A solution of 6.8 parts of m-nitrotoluene and 6 parts of benzyl cyanide in 12 parts of pyridine at 20 ° in a suspension of 25 parts a paste obtained by grinding equal parts of potassium hydroxide and benzene in 40 parts of pyridine with stirring. When the entry is complete, the mixture is stirred for a further 1/2 Hour at the same temperature and then works according to the indications of Example i on. The reaction product, a water-insoluble colorless oil, solidifies crystalline when standing. It dissolves easily in ether, glacial acetic acid, and methyl Ethyl alcohol and pyridine. Its solution in pyridine is made on the addition of potassium hydroxide deep blue, while its solution in alcohol turns blue-violet.

Example 12 In a solution of 17.4 parts of 8-nitroquinoline and 13 Parts of benzyl cyanide in 150 parts of pyridine are stirred and passed through at 15 ° a stream of dry air 40 parts of potassium hydroxide by grinding equal parts and benzene paste, diluted with 60 parts of pyridine, added, whereupon one the mixture stirred for a further 2 hours at 15 to 20 °. When working up according to the information in Example i, a condensation product is obtained which crystallizes from dilute pyridine in pale yellow prisms. It is easily soluble in glacial acetic acid, acetone and pyridine; the solution in the latter is provided by potassium hydroxide dyed red. The condensation product dissolves in a light yellow color in hot dilute hydrochloric acid and is precipitated again from this solution by ammonia.

Example 13 In a solution of 12 parts of a-nitroanthraquinone and 6 Parts of benzyl cyanide in zoo parts of pyridine are at -2o ° q.o parts of a through Grinding equal parts of potassium hydroxide and benzene obtained paste, diluted with 100 parts of pyridine, gradually entered. After completing the entry you increase the temperature slowly to -f- 15 °, the initially bluish-tinged red color the reaction liquid turns into cloudy blue-violet. After stirring for 2 hours at 20 ° is mixed with zoo parts benzene and sucked off after standing for some time. Of the Filter residue is washed out with water, the condensation product in the water-insoluble part remains, from which it is withdrawn by the ether. After evaporation of the ether and recrystallization of the residue from dilute acetone are obtained almost colorless crystal druses. They easily dissolve in ether, alcohol, and pyridine; the The solution in the latter is colored carmine-red by adding potassium hydroxide.

EXAMPLE 14 32 parts of caustic potash are gradually introduced into a mixture of 61.5 parts of nitrobenzene with 59 parts of benzyl cyanide with strong cooling at -5 ° to -10 °. The resulting solid, violet mass is added to a mixture of ice and hydrochloric acid, whereupon steam is passed through. The 4-hydroxylaminodiphenylacetonitrile described in Example: 2 can be obtained from the residue by extraction with dilute sodium hydroxide solution or by recrystallization from benzene.

Example 15 io, 9 parts of i # 5-dinitronaphthalene and 3.6 parts of malononitrile are dissolved in 17o parts of pyridine, it can be at 20 ° while passing a dry air stream 3o parts of a same by grinding parts of potassium hydroxide and pyridine obtained paste, diluted with 3o Share pyridine, gradually entered. The reaction mixture is stirred for 1 hour at 20 °, then for a further 2 hours at 40 °, whereupon it turns bluish-tinged red. After cooling, benzene is added, the mixture is filtered off with suction after standing for a while, washed with benzene and the residue is taken up in water. The water-insoluble part, a brown-red powder, dissolves easily in glacial acetic acid, benzene and pyridine; its solution in the latter turns carmine-red on the addition of potassium hydroxide.

EXAMPLE 16 In a solution of 3 parts of o-nitroanisole and 2.5 parts of benzyl cyanide in 25 parts of pyridine, 5 parts of a paste obtained by grinding equal parts of potassium hydroxide and benzene are diluted with 7 parts at 20 ° while stirring and passing through a stream of dry air Pyridine. The blue-violet mixture is then held at 2o to 25 ' with stirring for a further 2 hours. If you work according to the information in example i; in this way a yellow condensation product is obtained which crystallizes from benzene, alcohol or glacial acetic acid in yellow needles. It is easily soluble in many organic solvents; its solution in pyridine is colored bluish-red by potassium hydroxide; in alkalis it dissolves with a yellow-brown color. Upon analysis, the product appears to be a hydroxylaminomethoxydiphenylacetonitrile.

Example 17 In a solution of 15 parts of m-nitrobenzaldehyde and 13 Parts of benzyl cyanide are added at 0 ° with stirring and passing through a stream of dry air 36 parts of a obtained by grinding equal parts of potassium hydroxide and benzene Paste, diluted with 50 parts of pyridine, added; after the entry is completed the mixture, which turns red-violet, was kept at 0 ° for a further 2 hours with stirring. It is then diluted with benzene, filtered off with suction and the filtrate is concentrated on a water bath a. A gray-brown, solid reaction product is precipitated here, which is obtained by recrystallization from glacial acetic acid in colorless flakes. It solves Easily in benzene, pyridine and glacial acetic acid, slightly heavier in alcohol. His solution in pyridine, the addition of potassium hydroxide turns carmine on warming.

Example 18 27.1 parts of 3'-nitro-2-benzoylbenzoic acid and 4.5 parts of acetonitrile are dissolved in 100 parts of pyridine, whereupon the resulting solution is in a suspension of 48 parts of a paste obtained by grinding equal parts of potassium hydroxide and benzene in i oo parts of pyridine is introduced with stirring and passing through a stream of dry air. The mixture is then heated to 85 'for 1 hour and then worked up as described in Example i. A light brown reaction product is obtained which dissolves in aqueous alkalis (also in soda solution) with a yellow-brown color. In a mixture of pyridine, potassium hydroxide and a little methanol it dissolves with a bluish-tinted red color.

If one condenses 3'-nitro - q. ' - methyl-2-benzoylbenzoic acid with Acetonitrile at 30 to 35 ° under otherwise identical conditions, a product is obtained of similar properties.

EXAMPLE 19 In a solution of 1M parts of i-nitro # naphthalene and 7.2 parts of malonitrile in 15o parts of pyridine, 24 parts of a paste obtained by grinding equal parts of potassium hydroxide and benzene are added at: 25 'while stirring and passing through a stream of dry air registered. The mixture, which turns intensely carmine-red, is then held at 35 ° for a further 2 hours and then worked up according to the information in Example i. This gives a reaction product which dissolves in aqueous alkalis with a brownish-violet color. Its solution in pyridine turns red-violet on the addition of potassium hydroxide. Other nitronaphthalene derivatives, such as. B. i-chloro-4-nitronaphthalene, can in a similar manner, for. B. be condensed with benzyl cyanide.

Example 2o A mixture of 15.3 parts of benzyl cyanide and 2o parts Pyridine is in a suspension full 2 parts of finely ground potassium hydroxide and 10 parts of p-nitranisole entered in 10 parts of pyridine at -5 °. The thus obtained The mixture is stirred for a few hours at -5 ° and then diluted with benzene. It is then filtered and the residue is washed with benzene and ether. The received The residue is dissolved in water, whereupon the aqueous solution is acidified and washed with ether is extracted. The essential extract is evaporated to dryness and the here residue obtained by fractional crystallization from petroleum ether. Man. receives a product that is sparingly soluble in petroleum ether in the form of colorless crystals. According to the analysis and behavior, the product obtained is similar to that according to the example i obtained nitrodiphenylacetonitrile identical.

A colorless crystallization product is also obtained, which in Petroleum ether is more soluble.

Claims (1)

Claim: Process for the preparation of condensation products of the aromatic series, characterized in that aromatic nitro or nitroso compounds which are in the p-position and / or in at least one o-position to a nitro or. Nitroso group containing a halogen or hydrogen atom, condensed in the presence of alkaline condensing agents with compounds which contain at least one methyl or methylene group which is adjacent to an activating group.