KR840001961B1 - Process for the preparation of anilines substituted by chlorine in the meta-position - Google Patents

Abstract

Anilines of formula (I), substd. by chlorine in the metaposition, are prepd. by reacting chlorine-substd. benzene derivatives (II) contg. nitrogen in an aq. phase with H2, while heating the reactants under pressure in the presence of an aq. reaction medium, which has a pH acidity of less than 1.5, H+ ion conc. of 0.5-12 gm ion/ , and I- ion conc. of at least 10-6 gm ion/l (or Br- ion conc. of at least 0.01 gm ion/l). In formulas, X' and X" are H or Cl, one of them being Cl; Y is H or O; R',R", and R"' are H or Cl, one of them being Cl.

Description

Method for preparing chlorine substituted aniline

The present invention relates to a method for preparing chlorine substituted aniline in the meta position.

In detail, the present invention relates to a method for producing chlorine-substituted aniline in the meta position by hydrogenation of a nitrogen-containing aromatic compound in which at least two halogens are substituted.

French Patent 2,298,531 describes a process for producing chloroaniline substituted at the meta position by reacting polychloroaniline with hydrogen. However, the method described in the patent described in the above-mentioned patent requires high pressure and a very large amount of hydrochloric acid, which causes serious corrosion problems.

It is an object of the present invention to provide a process which makes it possible to produce chlorine substituted aniline in meta position from several halogen-substituted nitrogen-aromatic compounds in good yield.

Another object of the present invention is to provide a method for preparing chlorine substituted aniline in the meta position using a chlorine substituted nitro compound (substituted nitrobenzene, etc.) or a chlorine substituted amino compound (polychloroaniline, etc.) as a starting material.

It is still another object of the present invention to provide a process for preparing chlorine substituted aniline in the meta position using an appropriate pressure.

It is another object of the present invention to provide a process for preparing chlorine substituted aniline in the meta position using an appropriate reaction temperature.

It is still another object of the present invention to provide a process for preparing chlorine substituted aniline in the meta position using suitable corrosion conditions.

Other objects and advantages of the present invention will be apparent from the following description.

This aim is to aniline in which the nitrogen-containing benzene derivative of the following structural formula (I) is chlorine-substituted in the meta position by a reaction in a liquid phase and an acid medium under pressure and heating in the presence of a noble metal of Group VIII of the periodic table. It can be achieved by the method of manufacturing.

Wherein Y represents a hydrogen atom or an oxygen atom, X ', X "is hydrogen or a chlorine atom, at least one of them is a chlorine atom, and R', R" and R '' 'are hydrogen or a chlorine atom At least one of these is a chlorine atom.

As described above, the reaction may be performed in the liquid phase. That is, it is advantageous to carry out this reaction in an inert organic or inorganic solvent under operating conditions. An inert solvent means a solvent that does not cause a chemical reaction. Preferred of these is water.

The acidity of the reaction medium generally has a pH (if aqueous) of 1.5 or less, preferably 1 or less. The H ⁺ ion concentration in this medium is generally 0.5-12 g ions / liter, preferably 1-6 g ions / liter.

It can also be used as the highest concentration of acid, but there is no benefit.

The acidity of this reaction medium can be achieved by strong inorganic acids or strong organic acids such as sulfuric acid, phosphoric acid or hydrochloric acid, but preference is given to using hydrochloric acid, most preferably hydrochloric acid. In any case, in view of the presence of chlorine ions resulting from dehalogenation and the presence of iodine and bromine ions characteristic of the present invention, this reaction always results in at least some of the mediation of the presence of hydrochloric acid, hydroiodic acid and / or hydrobromic acid. Can be performed. However, it is not necessary to limit the acid used as long as these acids are dissolved in the medium, and the strength of the acid (pH or H ⁺ concentration) and the concentration of anions (halide ions) required for this reaction are discussed above and below. And support for properties.

It is carried out in the liquid phase according to the invention (catalysts of noble metals which are mostly in solid phase are courtesy). This liquid phase is homogenized to form a solution, that is, when Y represents an oxygen atom in the structural formula (I), and this kind of liquid phase contains a reactant, a reaction product and a solvent, or a solvent which may be present. It is also possible to carry out the reaction in two liquid phases.

The pressure at which this reaction is carried out is generally carried out at 3 bar (relative pressure) and preferably at 5 bar or more. There is no absolute limitation on the pressure, but for economic reasons it is advantageous to perform below 100 bar, preferably below 30 bar.

Reaction temperature is generally 90-300 degreeC, Preferably it is 110-200 degreeC. In the case of using highly volatile acids, compounds other than hydrogen in the vapor phase have a fairly high partial pressure (a vapor phase means a vapor phase in the liquid reaction medium). The operating conditions are selected such that the partial pressure of hydrogen is 10 to 80% of the voltage (relative pressure), preferably 30 to 60%.

Precious metals constituting the base of the catalyst used in the present invention are ruthenium, rhodium, palladium, osmium, iridium, platinum, and metals belonging to the Group VIII group, among which platinum is most preferred. The metal may be in the form of a metal or in the form of a compound, but in general, under the reaction conditions, the compound is preferably used in the form of a metal since the compound is easily reduced to a metal form (oxidation value = 0). This catalyst may or may not be supported. A support known to support the catalyst is used as the catalyst support, which has water resistance and acid resistance. Activated carbon, silica and barium sulfate are particularly suitable as supports, and carbon black is a preferred support. It is advantageous for the catalyst and its support to be fine powders and very suitable for having a specific surface area of at least 100 m 2 / g.

The amount of catalyst used is generally 0.05 to 10%, preferably 0.5 to 5%, by weight ratio of the noble metal in the catalyst to the compound of formula (I) to be treated.

The iodine and / or bromine ions used in the present reaction may be introduced in various forms, in particular in the form of hydrochloric acid and / or hydrobromic acid, which are generally halides (iodine and / or bromide) or halogenated It is preferred to introduce in the form of hydrogen [hydrogen iodide and / or hydrogen bromide]. Iodide or bromine ions are alkali or alkaline earth metal iodides or bromide such as iodide or bromide of lithium, potassium or ammonium. These ammonium salts can be quaternary ammonium salts or non-quaternary ammonium salts (eg NH ₄ ⁺ ). The hydrogen iodide or hydrogen bromide is preferably an iodide hydride or bromide of substituted aniline, such as the amine of formula (I) (Y = H) and / or the substituted aniline prepared according to the invention. As mentioned above, chlorine ions are produced during the reaction, and in this respect the reaction always takes place in the presence of hydrochloric acid. The amount of iodine in the reaction medium is usually 10 ^{−6 to 1} g ions / liter, preferably 0.0001 to 0.1 g ions / liter. It is advantageous to use a small amount of iodide since there is no need to recover them at the end of the reaction. The amount of bromine ions in the reaction medium is 0.01-10 g ions / liter, preferably 0.1-6 g ions / liter.

The following compounds are preferred for this compound of formula (I) which can be treated according to the process. 2,3-dichloronitrobenzene and 2,3-dichloroaniline, 2,5-dichloronitrobenzene and 2,5-dichloroaniline, 3,4-dichloronitrobenzene and 2,3,4-dichloroaniline, 2,3 , 4-trichloronitrobenzene and 2,3,5-trichloroaniline, 2,3,5-trichloronitrobenzene and 2,3,6-trichloroaniline, 2,3,6-trichloronitrobenzene 2,4,6-trichloroaniline, 2,4,5-trichloronitrobenzene and 2,4,5-trichloroaniline, 3,4,5-trichloronitrobenzene and 3,4,5-trichloro Aniline, 2,3,4,6-tetrachloronitrobenzene and 2,3,4,6-tetrachloroaniline, 2,3,4,5-tetrachloronitrobenzene and 2,3,4,5-tetrachloro Aniline, 2,3,5,6-tetrachloronitrobenzene and 2,3,5,6-tetrachloroaniline and pentachloronitrobenzene and pentachloroaniline, 4,5,6-trichloro-2-methylnitrobenzene And 4,5,6-trichloro-2-methylaniline, 2,5-mechloro-4-methylnitrobenzene and 2,5-di Chloro-4-methylaniline, 2,3,5,6-tetrachloro-4-methylnitrobenzene and 2,3,5,6-tetrachloro-4-methylaniline, 2,5-dichloro-3,4- Dimethylnitrobenzene and 2,5-dichloro-3,4-dimethylaniline, 2,5-dichloro-4-ethylnitrobenzene and 2,5-dichloro-4-ethylaniline, 2,5-dichloro-4-propylnitro Benzene and 2,5-dichloro-4-propylaniline, 3,4,6-trichloro-2-lobenzylnitrobenzene and 3,4,6-trichloro-2-benzylaniline, 2,2'-dinitro- 3,5,6,3 ', 5', 6'-hexachlorodiphenylmethane and 2,2'-diamino-3,5,6,3 ', 5', 6'-hexachlorodikenylmethane, 2-nitro-3,4,5-trichlorodiphenyl and 2-amino-3,4,5-trichlorodiphenyl, 4,4'-dinitrooctachlorodiphenyl and 4,4'-diaminooctachlorodi Phenyl, 4,5-dichloro-2-methoxynitrobenzene and 4,5-dichloro-2-methoxyaniline, 3,4, -dichloro-2-damethoxynitrobenzene and 3,4-dichloro-2-meth Oxyaniline, 3,6-dichloro-2-methoxynitroben And 3,6-dichloro-2-methoxyaniline, 5,6-dichloro-2-methoxynitrobenzene and 5,6-dichloro-2-methoxyaniline, 3,4,6-trichloro-2-romethoxy Nitrobenzene and 3,4,6-trichloro-2-doxyaniline, 3,4,5-trichloro-2-methoxynitrobenzene and 3,4,5-trichloro-2-methoxyaniline, 3 3,4,5,6-tetrachloro-2-methoxynitrobenzene and 3,4,5,6-tetrachloro-2-methoxynitrobenzene and 3,4,5,6-tetrachloro-2-methoxy Aniline, 4,5-dichloro-3-methoxynitrobenzene and 4,5-dichloro-3-methoxyaniline, 5,6-dichloro-3-methoxynitrobenzene and 5,6-dichloro-3-methoxy Aniline, 2,5-dichloro-3-methoxynitrobenzene and 2,5-dichloro-3-methoxyaniline, 4,5,6-trichloro-3-methoxynitrobenzene and 4,5,6-trichloro Rho-3-methoxyaniline, 2,4,5,6-tetrachloro-3-methoxynitrobenzene and 2,4,5,6-tetrachloro-3-methoxyaniline, 2,3-dichloro-4 -Methoxynitrobenzene and 2,3-di Roro-4-methoxyaniline, 2,5-dichloro-4-methoxynitrobenzene and 2,5-dichloro-4-methoxyaniline, 2,3,6-trichloro-4-methoxyanilinebenzene and 2 , 3,6-trichloro-4-methoxyaniline, 2,3,5-trichloro-4-methoxynitrobenzene and 2,3,5-trichloro-4-methoxyaniline, 2,3,5 , 6-Tatrachloro-4-methoxynitrobenzene and 2,3,5,6-tetrachloro-4-methoxyaniline, 4,5-dichloro-2-phenoxynitrobenzene, 4,5-dichloro- 2-phenoxyaniline, 3,4,5,6-tetrachloro- 2-phenoxynitrobenzene and 3,4,5,6-tetrachloro-2-phenoxyaniline, 2,4,5,6-tetra Chloro-3-phenoxynitrobenzene and 2,4,5,6-tetrachloro-3-aniline, 2,5-dichloro-4-phenoxynitrobenzene and 2,5-dichloro-4-phenoxyaniline, 2 , 3,5,6-tetrachloro-4-phenoxynitrobenzene and 2,3,5,6-tetrachloro-4-phenoxaniline.

Among the anilines substituted with chlorine in the meta position, the following compounds are preferred and can be prepared according to the method of the present invention. Meta-chloroaniline and 3,5-dichloroaniline, also 5-chloro-2-methylaniline, 5-chloro-3-methylaniline, 3-chloro-4-methylaniline, 3,5-dichloro-4-methylaniline , 5-chloro-3,4-dimethylaniline, 3-chloro-4-ethylaniline, 3-chloro-2-benzeneaniline, 4,4'-diamino-2,6,2 ', 6'-tetrachloro Diphenyl, 3-chloro-2-methoxyaniline, 5-chloro-2-methoxyaniline, 3,5-dichloro-2-methoxyaniline, 3-chloro-4-methoxyaniline, 5-chloro-3 -Methoxyaniline, 3,5-dichloro-4-methoxyaniline, 3-chloro-2-phenoxyaniline, 5-chloro-2-phenoxyaniline, 3,5-dichloro-2-phenoxyaniline and 3 , 5-dichloro-4-phenoxyaniline.

The process according to the invention can be carried out continuously or discontinuously. At the end of the reaction, the catalyst can be separated by filtration or decantation if necessary, and the amine substituted by chlorine in the meta position can be separated by known methods, i.e. solvent extraction and / or distillation, and neutral or The basic reaction mixture can be treated with an alkalizing agent to convert the amine chlorided in the acid medium to an unchlorinated amine. In the case of using bromine ions, it is advantageous to recover these ions in order to recycle them in the following operation.

The process according to the invention is very advantageous because of the good selectivity for chlorine substituted amines in the meta position and the mild reaction conditions under which this is carried out. Chlorine-substituted amines in the meta position produced in this way can be used in particular for the preparation of pesticides.

Next, an Example is given in order to demonstrate this invention in detail, This Example illustrates this invention but does not limit this invention.

Example 1

1.67 g of 2,3,4,5-tetrachloroaniline, a catalyst consisting of palladium supported on 0.07 g of activated carbon (specific surface area of activated carbon: 1,100 m 2 / g; ratio of palladium: 10% by weight), 4 moles of 106 cc 4 An aqueous hydrochloric acid solution having a concentration of / liter and an aqueous hydrochloric acid solution having a concentration of 7.6 mol / liter of 13.3 cc are placed in a 250 cc autoclave coated with titanium on the inside.

The autoclave is closed and then purged with argon and then with hydrogen. The temperature is raised to 190 ° C, the pressure of the autoclave is increased, and hydrogen is injected until the voltage reaches 20 bar and the hydrogen partial pressure reaches 6 bar when the temperature reaches 190 ° C.

The reaction is allowed to proceed for 1 hour under these conditions. After cooling, the liquid reaction mixture was alkalized with aqueous sodium hydroxide solution, the catalyst was filtered off, 3,5-dichloroaniline was extracted from the aqueous layer using methylene chloride, and the methyl chloride thus obtained was dehydrated over sodium sulfate, and the solvent was fractionated in vacuo. The conversion of tetrachloroaniline was 100% and the yield of 3,5-dichloroaniline was 98.2%.

Example 2

Instead of a solution having a concentration of 4 mol / liter of 106 cc, an aqueous hydrochloric acid solution having a concentration of 0.8 cc / liter of 98 cc was used, except that 68 g of anhydrous sodium iodide was used instead of 13.3 cc of hydroiodic acid. It carried out similarly to the method of 1.

The yield of 3,5-dichloroaniline was 92.2%, and the conversion of tetrachloroaniline was 100%.

Example 3

Except for using an aqueous solution of hydrochloric acid having a concentration of 115 cc of 0.8 mol / liter in place of a solution having a concentration of 4 mol / liter of 106 cc and using 14.8 g of anhydrous sodium iodide in place of 13.3 cc of hydroiodic acid solution. Was carried out in the same manner as in Example 1. 3,5-dichloroaniline was obtained, containing 5.8% of richloroaniline, 0.3% of methylchloroaniline and 3.3% of metachloroaniline, with a yield of 93.6% of dichloroaniline and a conversion of tetrachloroaniline of 100%. to be.

Example 4

The same procedure as in Example 1 was carried out except that an aqueous hydrochloric acid solution having a concentration of 120 cc of hydrochloric acid and an aqueous solution of 0.01 mol / liter of 0.4 cc was used and the reaction time was 5 hours.

3,5-dichloroaniline containing 3.5% metachloroaniline was obtained in a yield of 96%, and the conversion of tetrachloroaniline was 100%.

Example 5

In Example 1, instead of using 1.67 g, 0.42 g of tetraaniline was used, and instead of a solution having a concentration of 4 mol / liter of 106 cc, an aqueous solution of hydrochloric acid having a concentration of 2.5 mol / liter of 120 cc was used, and 13.3 cc Instead of hydrogen iodide, 0.11 g of anhydrous potassium iodide was used and the reaction time was carried out for 2 hours and 40 minutes instead of 1 hour, and the pressure was carried out in the same manner as in Example 1 with a pressure of 10 bar and a hydrogen partial pressure of 5 bar. did.

3,5-dichloroaniline containing 2.5% metachloroaniline and 2.5% aniline was obtained in a yield of 86%. The conversion of trichloroaniline was 100%.

Example 6

1.17 g of 2,3-dichloroaniline instead of tetrachloroaniline, 0.56 g of palladium based catalyst, aqueous solution of hydrochloric acid having a use of 120 cc of 2.5 mol / liter, 0.2 g of potassium iodide in place of hydrogen iodide and reaction The temperature was increased to 160 ° C. and the voltage was 13 bar, and the reaction time was performed in the same manner as in Example 1 except that the reaction time was 3 hours.

The conversion of 2,3-dichloroaniline was 98.2% and the yield of metachloroaniline for the converted dichloroaniline was 95.6%.

Example 7

Example using 3,4-dichloroaniline instead of 2,3-dichloroaniline, using hydrochloric acid having a concentration of 1 mol / liter, using 0.04 g of sodium iodide and making the reaction time 45 minutes It carried out similarly to the method of 6.

3,4-dichloroaniline was completely converted and meta-chloro aniline was obtained in a yield of 97.1%.

Example 8

139 g of dichloronitrobenzene, 0.56 g of catalyst (palladium / carbon black with 10% palladium), an aqueous hydrochloric acid solution having a concentration of 1 mol / liter of 120 cc and 0.04 g of potassium iodide were placed in an autoclave of 225 cc.

The autoclave was burned with argon and filled with hydrogen to 4 bar pressure. After the autoclave had a temperature of 160 ° C. and a pressure of 13 bar, the autoclave was cooled for 1 hour and 40 minutes. The conversion of dichloronitrobenzene was 100% and the yield of metachloroaniline was 92.9%.

Example 9

120 cc of 4N aqueous hydrochloric acid solution, 0.14 g of palladium based catalyst used in Example 1 and 0.011 g of potassium iodide were introduced into a 250 cc autoclave whose inner wall was covered with tantalum.

The autoclave was sealed, cleaned with argon and filled with hydrogen. The voltage was 8 and the partial pressure of hydrogen was heated at 130 ° C. for 2 hours and 30 minutes at 5 bar. During the reaction, all of the trichloroaniline was converted, and the yield of 3,5-dichloroaniline was 99%.

Example 10

120 cc of aqueous 4N hydrochloric acid solution, 3.54 g of 2,4,5-trichloroaniline 1.48 g of palladium based catalyst (palladium on activated carbon containing 10% palladium) and 0.011 g of iodide as used in the above examples Potassium was placed in a 250 cc autoclave coated with tantalum on the inner wall.

The autoclave was purged with argon and after filling with hydrogen, the autoclave was heated at 160 ° C. for 240 minutes at a voltage of 18 bar and a hydrogen partial pressure of 13 bar.

The conversion was 100% and the yield of 3-chloroaniline was 98.2%.

Example 11

Except for introducing 120 cc of 4N aqueous hydrochloric acid solution, 0.354 g of 2,3,5-trichloroaniline, 0.140 g of palladium based catalyst (active elastic palladium containing 10% palladium) and 0.011 g of potassium iodide The operation of Example 1 described above was repeated.

The autoclave was heated at 160 ° C. under a voltage of 18 bar and a hydrogen partial pressure of 13 bar for 160 minutes.

The conversion was 100% and the yield of 3,5-dimeroaniline was 96.8%.

Example 12

A solution of hydrochloric acid containing 120 cc of 4 mol / liter, 1.67 g of 2,3,4,5-tetrachloroaniline, 0.07 g of catalyst used in Example 1 and 7.14 g of potassium bromide were added and the method of Example 1 I did the same.

The autoclave was heated at 190 ° C. for 170 minutes under a voltage of 20 bar and a partial pressure of hydrogen of 6 bar.

The conversion was 100% and the yield of 3,5-dichloroaniline was 90%.

Example 13

120 ml of 4N aqueous hydrochloric acid solution, 420 mg of 2,3,4,5-tetrachloroaniline, 140 mg of the catalyst used in Example 1 and 1.1 mg of potassium iodide (i.e., a concentration of 5.5 × 10 ^{−5 in} the medium) Except that was carried out in the same manner as in Example 1.

The autoclave was heated at 160 ° C. for 220 minutes at a voltage of 9 bar and a hydrogen partial pressure of 4.5 bar.

The conversion of tetrachloroaniline was 100% and the yield of 3,5-dichloroaniline was 92.5%.

Example 14

Example 1 except using 120 mm aqueous hydrochloric acid solution, 4N 9420 mg 2,3,4,5-tetrachloroaniline, a catalyst containing 1.1% palladium supported on 140 mg activated carbon and 11 g potassium iodide Do the same with the method.

The autoclave was heated at 160 ° C. under a voltage of 18 bar and a hydrogen partial pressure of 13 bar for 180 minutes. The yield of 3,5-dichloroaniline was 98.1%. The conversion of tetrachloro aniline was 100%.

Example 15

Example 14 was obtained in the same manner as in Example 14 except for using the 2.8% palladium containing catalyst supported on the same support by the same method of 140 mg instead of the catalyst containing 140 mg of 1.1% palladium.

Example 16

2 kg of 13.6% aqueous hydrochloric acid solution, a catalyst consisting of palladium supported on activated carbon (the specific surface area of black is 1100 m 2 / g, the palladium response is 10% by weight), 11.7 g of anhydrous solid potassium iodide (i.e. 0.5 g of iodine per atom of palladium) was placed in a 3.6 l autoclave with tantalum-coated inner walls.

The autoclave was sealed and nitrogen filled and then filled with hydrogen. Hydrogen is then injected until the pressure is 3 bar. The temperature was raised to 160 ° C. and the autoclave pressure was increased. Hydrogen is injected to raise the pressure to 15.5 bar and the hydrogen partial pressure to 10 bar. One mole of 2,3,4,5-tetrachloronitrobenzene was injected over 2 hours and 30 minutes.

The reaction is stirred for 2 hours under the above conditions. After the reaction tube was cooled to 100 ° C. and emptied, the liquid reaction medium was neutralized with an aqueous sodium hydroxide solution, and then the catalyst was filtered off and extracted with toluene to obtain chlorosubstituted amine, mainly 3,5-dichloroaniline. The solvent was distilled off in vacuo. The conversion of 2,3,4,5-tetrachlorobenzene was 100% and the yield of 3,5-dichloroaniline was 94%.

Claims (1)

When the chlorine-substituted nitrogen-containing benzene derivative represented by the following structural formula (II) is heated and pressurized in the presence of a noble metal of Group 8 of the periodic table, the pH of the acid medium in the presence of iodine or bromion is 1.5 or less or the H ⁺ ion concentration in the aqueous reaction medium It is characterized by reacting liquid-phase hydrogenation in an aqueous medium of 0.5 to 12 grams / l and a proportion of iodine ions in the reaction medium of at least 10 ^-6 grams / l or more, or a bromine ion of at least 0.01 grams / l or more. Method for producing chlorine-substituted aniline at the meta position represented by the following structural formula (I).

In the above formula X 'and X "are hydrogen or chlorine atoms, at least one of which is a chlorine atom.

In the above formula, X 'and X "are as defined above; Y represents a hydrogen atom or an oxygen atom; R ', R "and R'" are hydrogen or chlorine atoms, at least one of which is a chlorine atom.