KR910004667B1 - A process for the production of-4-nitrodiphenylamine - Google Patents

Abstract

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Description

Method for preparing 4-nitrodiphenylamine

The present invention relates to a process for preparing 4-nitrodiphenylamine by reacting 4-nitrohalobenzene with a primary aromatic amine in the presence of potassium carbonate and a copper compound.

The reaction of halogennibenben with aromatic amines has long been known. For example, German Federal Patent No. 185,663 describes that this reaction can be carried out in the presence of an alkali carbonate and a copper compound as a catalyst.

It is also known that very slow reaction rates can be accelerated by carrying out the reaction in the presence of calcium carbonate and removing water in the reaction system by azeotropic distillation. According to Example 1 of US Pat. No. 2,927,943, somewhat pure 4-nitrodiphenylamine is obtained in 73% yield (based on theory) during the 21 hour reaction time under the above conditions. In addition, US Pat. No. 4,155,936 The reaction of the halogenonitrobenzene with the primary aromatic amine not only has a long reaction time, but also a secondary product (impurity) is formed such that nitrobenzene is formed by a large amount of tar and a reductive dehalogenation reaction to form nitrodiphenyl. It can be seen that the amine is contaminated. See: US Patent No. 3,313,854, Column 3,64,65.

To address this disadvantage, polar solvents have been added to the reaction mixture as cocatalysts. However, all polar solvents used herein also have disadvantages. For example, dimethylformamide used in US Pat. No. 3,055,940 forms secondary products that are volatile and difficult to separate under reaction conditions. Hexamethyl phosphate triamide used in US Pat. No. 3,055,940 and formanilide used in US Pat. No. 3,313,854 exhibit only a weak acceleration property in the presence of copper compounds in their catalytic amounts. Dimethylsulfoxide, acetanilide and salicylicanilide used in US Pat. Nos. 3,277,175, DE-AS 1518307 and DE-AS 1117594, respectively, also show no satisfactory effect and are used in DE-OS 2633811. The same also applies to N-methyl pyrrolidone and 1ε-caprolactam used in Japanese Patent No. 56 / 022,751. The polyether addition process described in US Pat. No. 4,155,936 has the disadvantage that the material added according to the method used in the final treatment step remains in the final product or in the waste water.

-하이드록시벤잘아미노페졸, 다가인산염, 카복시메틸 머캡토석신산 또는 살리실알데히드의 식프염기를 첨가하는 방법이 기술되어 있다.As another way to reduce the accumulation of tar, US Pat. No. 3,131,736 discloses amino carboxylic acids, alkyldiaminopolycarboxylic acids and salts thereof, dissalicyldiaminoalkanes,

A method of adding a phosphobase of hydroxybenzalaminophenzol, polyphosphate, carboxymethyl mercaptosuccinic acid or salicylate is described.

However, there is a problem with the use of such materials in the final processing steps.

According to the present invention, the halogenated nitrobenzene of the following general formula (II) is reacted with the primary aromatic amine of the following general formula (III) in the presence of potassium carbonate and a copper compound to form 4-nitrodiphenyl of the following general formula (I) A method of preparing an amine, characterized in that at least one other metal compound of Groups IIIA, IVA, VA and VIA of the Periodic Table or Groups IIB, IVB, VB, VIB, VB and VB and optionally formformyl derivatives of aromatic amines is added. A method is provided.

Wherein R ¹ , R ² , R ³ and R ⁴ may be the same or different and represent a hydrogen atom or a C ₁ -C ₉ alkyl group and X represents chlorine or bromine.

Preferred alkyl groups in formula (I) are alkyl having 1 to 3 carbon atoms.

The process according to the invention is preferably used to prepare 4-nitrodiphenylamine from 4-nitrochlorobenzene and aniline.

Examples of copper catalysts that can be used in the process according to the invention include copper iodide (I), copper chloride (I), copper chloride (II), copper bromide (I), copper bromide (II) and copper cyanide (I). , Copper oxide (I), copper oxide (II), copper carbonate (II), basic copper carbonate (II), copper sulfate (II), copper nitrate (II), copper formate (II), copper acetate (II) And mono- or di-copper organic and inorganic coordination compounds. Of these, oxygen-containing copper compounds such as copper (II) oxide, copper carbonate (II), basic copper carbonate (II) or copper (I) are preferred, and the copper catalyst is 0.1 based on the used halonitrobenzene. To 5% by weight, preferably 0.5 to 2% by weight. The copper catalysts can be used alone or in combination with each other.

The additional metal compound is added in an amount of 1 to 50% by weight, more particularly 5 to 25% by weight, based on the copper compound. When several metal compounds are added, each is added in the specified amount.

Suitable halonitrobenzenes are, for example, 4-nitrochlorobenzene, 4-nitrobromobenzene, 4-nitro-2-methylchlorobenzene and 4-nitro-3-methylchlorobenzene.

Examples of primary aromatic amines used are aniline, o, m- and p-toluidine, 4-ethylaniline, 4-butylaniline, 4-isopropylaniline, 3,5-dimethylaniline and 2,4-dimethylaniline have.

The aromatic amines can of course also be used in the form of mixtures, in particular in the form of mixtures of isomers. In general, about 1 to 6 moles, preferably 1.5 to 3 moles, more preferably 1.7 to 2.5 moles of aromatic amine are used per mole of halonitrobenzene.

Preferred metals are thallium, tin, bismuth, zinc, mercury, vanadium, chromium, manganese and cobalt, which are chlorides, bromide, iodide, sulfates, oxides, hydroxides, carbonates, bicarbonates, formaldehydes, acetates, propiodes It can be used in the form of nate, cyanide, nitrate and phosphate.

Preferred as metals are bicarbonates, carbonates and oxides, in particular when zinc, tin, chromium, vanadium and manganese are used.

Formyl derivatives of suitable aromatic amines are all compounds of the benzene and naphthalene series. The formyl compound is used in an amount of 10 to 300% by weight, preferably 50 to 200% by weight, based on the amount of the copper compound.

According to the process of the present invention, the compound can be obtained in better yield than the processes known so far, and other disadvantages can be avoided. As another component, cesium compounds, in particular cesium bicarbonate, cesium carbonate or cesium hydroxide, may be added to further increase the yield.

Potassium carbonate can be used in an amount equivalent to or equivalent to 1.5 times the equivalent.

The reaction is preferably carried out under anhydrous conditions.

The water formed during the reaction is distilled from the reaction mixture by the use of a co-enzyme such as xylene, toluene, benzene, chlorobenzene, chlorotoluene, aniline and / or toluidine, preferably xylene or toluene. It is advantageous to remove.

In some cases, the process of the invention can be carried out in the presence of a diluent, for example an inert organic hydrocarbon such as xylene. Moreover, aromatic primary amine itself can be used as a solvent.

The reaction temperature of the process of the present invention can vary widely. Generally, it is 140 to 225 ° C, preferably 180 to 210 ° C, more preferably 190 to 205 ° C.

The process of the invention can be carried out continuously or batchwise by standard methods.

Likewise, the reaction mixture can be treated in several ways. Salts present in the reaction mixture may be separated by centrifugation or filtration at elevated temperatures. After washing with warm xylene and drying, a light gray powdery solid is left. Unreacted halogennibenzene and primary aromatic amines are removed from the filtrate using steam, in which case nitrodiphenylamine generally accumulates in the form of particles. Other methods that can be used include distilling a portion of the filtrate in vacuo to give the product as a residue, or separating 4-nitrodiphenylammine as completely as possible by crystallization, and / or adding the precipitant such as xylene to the filtrate. There is this. 4-nitrodiphenylamine accumulates in a very pure form and can be used directly for the next reaction.

The copper catalyst can be used repeatedly. In some cases, to maintain full activity, a small amount of new catalyst is added rather than the first used. If necessary, a small amount of accumulated mother liquor is separated to remove the secondary product from the circulator. Salts present in the reaction mixture may also be removed by stirring the reaction mixture with an amount of water necessary to dissolve the salt, preferably at elevated temperature (eg, 85-95 ° C.). After phase separation has taken place, the organic phase is further treated, for example, by distilling off or stripping components which are more volatile than 4-nitrodiphenylamine under steam distillation.

By the process of the invention, 4-nitrodiphenylamine can be obtained in a very pure form in a short time, yield of 85% or more. The formation of secondary products in the process according to the invention is only minute.

The 4-nitrodiphenylamine produced by the process of the present invention can be easily reduced to amino diphenylamine by known methods, which in themselves becomes an intermediate product useful for the preparation of stabilizers of dyes or rubbers. : US Patent No. 3,163,616]

Example 1

In a flask equipped with a stirrer, a reflux condenser and a water separator, 157.6 g of p-chloronitrobenzene, 180 g of aniline, 100 g of potassium carbonate, 15 ml of xylene and 2 g of copper oxide are heated together to 195 ° C. After 17 hours 11 ml of water are produced and the reaction is complete. Excess aniline, xylene and chloronitrobenzene are removed using steam. The crude nitrodiphenylamine is filtered off and dried. This gives 4-nitrodiphenylamine in 76% yield of theory, based on p-chloronitrobenzene.

Further testing is carried out according to example 1, with the results as follows.

Example 2

Example 1 was repeated with 2.5 g of formanilide. The reaction time is 15 hours and the yield increases to 78% of theory.

A further example is carried out according to example 1 with the addition of formanilide (X) to give the following results.

Claims (18)

A method for producing 4-nitrodifenylamine by reacting 4-nitrohalobenzene with a primary aromatic amine in the presence of potassium carbonate and a copper compound, wherein groups IIIA, IVA, VA and VIA of the Periodic Table of the Elements or IIB, IVB A formyl derivative of at least one aromatic amine of Group V, VB, VIB, VB and other metal compounds of Group VB is added. A process according to claim 1, wherein 4-nitrodiphenylamine is a compound of the general formula

Wherein R ¹ , R ² , R ³ , and R ⁴ may be the same or different and represent a hydrogen atom or a C ₁ -C ₉ alkyl group. The method of claim 1 wherein the 4-nitrochlorobenzene is reacted with aniline to produce 4-nitrodiphenylamine. 4. Process according to any one of the preceding claims, characterized in that a compound of thallium, tin, bismuth, zinc, mercury, vanadium, chromium, manganese or cobalt is used. The method of claim 1, wherein a compound of zinc, tin, chromium, vanadium or manganese is used. The method of claim 1, further comprising a cesium compound. The method according to claim 1, wherein the copper catalyst is used in an amount of 0.1 to 5% by weight based on the used halonitrobenzene, and the additional metal compound is in an amount of 1 to 50% by weight based on the copper compound. Using. The method of claim 1 wherein formanilide is added as formyl derivative. The process according to claim 1, wherein the reaction is carried out under anhydrous conditions at 140 to 225 ° C and water formed during the reaction is distilled off using a co-agent. The method according to claim 1, wherein the formyl derivative is added in an amount of 10 to 300% by weight based on the amount of the copper compound. A process for preparing 4-nitrodiphenylamine by reacting 4-nitrohalobenzene with a primary aromatic amine in the presence of potassium carbonate and a copper compound, comprising groups IIIA, IVA, VA and VIA of the Periodic Table of the Elements or IIB, IVB At least one of VB, VIB, VB and other metal compounds of Group VIII. 12. The method of claim 11, wherein 4-nitrodiphenylamine is a compound of the general formula:

Wherein R 1, R 2, R 3, and R 4 may be the same or different and represent a hydrogen atom or a C ₁ -C ₉ alkyl group. 12. The method of claim 11, wherein 4-nitrochlorobenzene is reacted with aniline to produce 4-nitrodiphenylimine. Process according to any of the preceding claims, characterized in that compounds of thallium, tin, bismuth, zinc, mercury, vanadium, chromium, manganese or cobalt are used. 12. The method of claim 11, wherein a compound of zinc, tin, chromium, vanadium or manganese is used. 12. The method according to claim 11, further comprising a cesium compound. 12. The copper catalyst according to claim 11, wherein the copper catalyst is used in an amount of 0.1 to 5% by weight based on the used halonitrobenzene, and the additional metal compound is in an amount of 1 to 50% by weight based on the copper compound. Characterized in that used as. The process according to claim 11, wherein the reaction is carried out under anhydrous conditions at 140 to 225 ° C and water formed during the reaction is distilled off using a co-agent.