JPH06219999A - Production of aminodiphenylether - Google Patents

Abstract

PURPOSE:To produce diaminodiphenylether in high yield and in high efficiency useful as a raw material of fiber use aromatic polyamides, medicines, agricultural chemicals, etc. CONSTITUTION:In producing an amino diphenylether by condensing a halonitrobenzene and an aminophenol in a reaction medium, (a) a nonprotonic organic polar solvent is used as a reaction solvent and further (b) a condensation reaction is carried out in the presence of a condensing agent consisting of an alkali metal hydroxide and an alkali metal carbonate as a dehalogenation condensing agent, especially a condensing agent obtained by baking a mixture of the alkali metal hydroxide and the alkali metal carbonate at >=150 deg.C, preferably at >=200 deg.C, to obtain an aminodiphenylether.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing amino diphenyl ether. For more details,
It relates to a novel method for producing amino diphenyl ether with good productivity by reacting halonitrobenzene and aminophenol in an aprotic organic polar medium in the presence of a special dehalogenating condensing agent. is there.

[0002]

2. Description of the Related Art Amino diphenyl ether is a pesticide,
It is a useful substance as a raw material for medicines and polymer materials. As a method for synthesizing such amino diphenyl ether, a method of synthesizing amino nitro diphenyl ether by reacting chloronitrobenzene and an alkali salt of aminophenol in an organic polar medium. Has been known since ancient times.

For example, in Japanese Examined Patent Publication No. Sho 47-18101,
A method for synthesizing para- or ortho-chloronitrobenzene and an alkali metal salt of aminophenol in an organic polar medium such as N, N-dimethylformamide is described. However, this method uses an alkali metal hydroxide as a dehalogenating agent, uses aminophenol as an alkali salt, and makes the reaction temperature relatively low (50 to 80 ° C.) to suppress the production of by-products. However, there are problems such as slow reaction speed.

Further, a method has also been proposed in which an alkali metal aminophenate is reacted with ortho- or para-halonitrobenzene under reflux in a liquid reaction medium containing N, N-dimethylformamide (Japanese Patent Publication No. Sho 5).
5-40573), this method has a problem in separation of N, N-dimethylformamide as a reaction medium and recovery thereof because the reaction is carried out at a high temperature.

Further, a method is proposed in which aminophenol and halonitrobenzene are reacted in an aprotic polar solvent in the presence of an alkali metal carbonate, preferably at 130 to 150 ° C., while distilling off water produced as a by-product. (Japanese Patent Publication No. Sho 63-19503). In this way,
Since the reaction is carried out while removing the by-product water out of the system, it is disadvantageous in terms of operation and equipment.

For the purpose of solving these problems, aminophenol and halonitrobenzene are condensed in a mixed solvent of N-methyl-2-pyrrolidone and water while adding an alkali metal hydroxide in the temperature range of 50 to 90 ° C. A method of reacting has been proposed (JP-A-62-81358). In this method, the reaction can be carried out at a relatively low temperature and the production of by-products can be suppressed, but in addition to the slow reaction rate, water has to be added to the reaction medium. In addition, there is a disadvantage in terms of equipment in the operation that the condensation reaction must be performed while adding alkaline metal hydroxide.

[0007]

DISCLOSURE OF THE INVENTION The present invention eliminates the above-mentioned problems in the conventional method, produces the amino diphenyl ether in a high yield with good productivity and advantageous operation and apparatus. It is intended to provide a way to do. Therefore, the object of the present invention is to react the halonitrobenzene and the aminophenol at a relatively low temperature, without the complicated operation of adding the alkali metal hydroxide to the system in the progress of the reaction, and An object of the present invention is to provide a method for industrially advantageously producing a desired amino diphenyl ether in a high yield without removing water by-produced therein.

[0008]

Means for Solving the Problems As a result of earnest research to achieve the above-mentioned object, the present inventor has found that by carrying out a condensation reaction between halonitrobenzene and aminophenol, amino.
In the method for producing diphenyl ether, it was found that the reaction product can be synthesized in a high yield at a relatively low temperature by performing the reaction in a specific reaction medium and in the presence of a specific dehalogenating condensing agent. Has reached the present invention.

That is, the present invention provides a method for producing an amino diphenyl ether by carrying out a condensation reaction between halonitrobenzene and aminophenol in a reaction medium, wherein (a) an aprotic organic polar medium is used as a reaction medium, And (b) a condensing agent composed of an alkali metal hydroxide and an alkali metal carbonate as a dehalogenating condensing agent, particularly a mixture of an alkali metal hydroxide and an alkali metal carbonate at 150 ° C or higher, preferably 200 ° C or higher. It is a method for producing amino diphenyl ether with good productivity by carrying out a condensation reaction in the presence of a calcining condensing agent at the above temperature.

Thus, according to the present invention, the condensation reaction of halonitrobenzene and aminophenol can be efficiently carried out even at a relatively low temperature, the by-product water is not removed during the reaction, and the addition of a condensing agent is also possible. A method capable of carrying out the reaction without need, in addition, suppressing the production of by-products that are difficult and difficult to separate from the target product, and capable of producing high-purity amino diphenyl ether in a high yield Will be provided.

The method of the present invention will be described in detail below. The halonitrobenzene used in the method of the present invention includes para-chloronitrobenzene, para-bromonitrobenzene and para-nitronitrobenzene.
(Mono) halonitrobenzenes such as iodonitrobenzene, or the hydrogen of these benzene rings is a methyl group,
Examples thereof include halonitroalkylbenzenes substituted with a lower alkyl group such as ethyl group.
Halonitrobenzenes, especially para-chloronitrobenzene, are preferably used.

Further, as aminophenol, meta-
Aminophenol, para-aminophenol, ortho-
Examples thereof include (mono) aminophenols such as aminophenols, and aminoalkylphenols in which hydrogen of these benzene rings is substituted with a lower alkyl group such as methyl group and ethyl group. Among them, meta-aminophenol Is preferably used.

In the method of the present invention, one object is to produce 3,4'-diaminodiphenyl ether which is useful as a raw material for aromatic polyamide fibers. In that case, para-chloronitrobenzene and meta-aminophenol are used. Is preferably selected.

The above-mentioned halonitrobenzene and aminophenol are preferably used alone, and on the other hand, when a mixture is used, the amino.
It becomes difficult to separate the target product from the diphenyl ethers with high purity. For example, in the condensation reaction of para-chloronitrobenzene and meta-aminophenol,
When 1 to 3% of ortho-chloronitrobenzene is mixed in para-chloronitrobenzene, the ortho-chloronitrobenzene reacts preferentially with 3-amino-
The purity of 4-nitrodiphenyl ether is significantly reduced. And 3-amino-2 ', which is a condensation product of ortho-chloronitrobenzene and meta-aminophenol.
-2,3 obtained by reducing nitrodiphenyl ether
When a polyamide is produced using a raw material (3,4′-diaminodiphenyl ether) in which a few percent of ′ -diaminodiphenyl ether is mixed and made into a fiber, the fiber performance becomes extremely low. Therefore, for the production of the polymer raw material for high-performance fibers, it is preferable to use high-purity halonitrobenzene and aminophenol individually, and the purity is preferably at least 98% or more. On the other hand, when it is used as an agricultural chemical or other dispersant, it is not limited thereto, and may be 90% or more, preferably 95% or more.

In the condensation reaction of halonitrobenzene and aminophenol, the ratio of both components used is such that halonitrobenzene is 0.9 to aminophenol.
It is preferably 1.1 mole times, and more preferably
It is 0.95 to 1.05 mol times.

In the method of the present invention, the above-mentioned starting materials (halonitrobenzene and aminophenol) are used to carry out a condensation reaction in a specific reaction medium (medium) in the presence of a specific dehalogenating condensing agent. Here, as the reaction medium (medium),
An aprotic organic polar medium is used. As the aprotic organic polar medium (medium), N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (N
MP), dimethyl sulfoxide (DMSO), sulfolane and the like. You may use these in mixture of 2 or more types as needed. Preferred aprotic organic polar media are N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMA).
c), N-methyl-2-pyrrolidone (NMP),
The individual use of each is preferred. The amount of these reaction media used is 0.5 to 10 times, preferably 1 to 5 times the total amount of halonitrobenzene and aminophenol.

On the other hand, as the dehalogenating condensing agent, a condensing agent obtained by mixing and calcining an alkali metal hydroxide and an alkali metal carbonate, specifically, an alkali metal hydroxide and an alkali metal carbonate is used. A condensing agent is used in which the mixture is calcined at a temperature of 150 ° C or higher, preferably 200 ° C or higher. Here, examples of the alkali metal hydroxide include potassium hydroxide and sodium hydroxide. As these alkali metal hydroxides, those having a purity of 85% or more are preferably used. Examples of the alkali metal carbonates include potassium carbonate, potassium hydrogen carbonate, sodium carbonate, sodium hydrogen carbonate, potassium sodium carbonate and the like.

These alkali metal hydroxides (MOH)
And alkali metal carbonate (Mx Hy CO ₃ ) (where M =
Na or K, x = 1 or 2, y = 0 or 1, x + y =
The ratio of 2) is (MOH) :( Mx Hy CO ₃ ) = 1:
The range may be from 99 to 50:50, and from the viewpoint of preparing the condensing agent,
This ratio is preferably 5:95 to 30:70.

As a method for preparing the dehalogenating condensing agent, there are typically two methods, a dry method and a wet method. In the dry method, for example, pellets of an alkali metal hydroxide such as potassium hydroxide and the above solid carbonate such as potassium carbonate are well mixed and pulverized, heated to 130 to 150 ° C., stirred at this temperature and dispersed and mixed. After that, it is a method of baking and drying at 250 to 500 ° C. This method is suitable when the amount of potassium hydroxide or the like exceeds 10% by weight with respect to the total amount of the condensing agent, but when the amount of potassium hydroxide or the like is 10% by weight or less, it is not preferable from the viewpoint of uniform dispersion. Therefore, when the mixing weight ratio of potassium hydroxide or the like is small, the wet method is adopted. That is, an appropriate amount of potassium hydroxide or the like corresponding to 1 to 10% by weight is dissolved in water, potassium carbonate or the like is added to this aqueous solution, and the mixture is immersed and mixed to obtain 100 to 150%.
A condensing agent is prepared by drying at 0 ° C. and then baking and drying at 150 to 500 ° C. for 2 to 10 hours.

In the method of the present invention, the amount of the above-mentioned condensing agent is usually not less than the stoichiometric amount of an alkali metal atom but not more than 1.2 mole times, preferably 1 to 1. It is 1 mol times. If the stoichiometric amount of alkali metal atoms in the condensing agent exceeds 1.2 mol, side reactions of the hydroxyl group and nitro group of the phenol occur, and the purity and yield of the target product tend to decrease.

The reaction temperature varies depending on conditions such as the type of halonitrobenzene as a raw material, the type and amount of polar medium, and the type of condensing agent used, but it is usually selected within the range of 80 to 150 ° C. The reaction time depends on the type of raw material,
Generally 1 to 1, though it depends on the reaction temperature, the type of condensing agent, etc.
It is in the range of 5 hours.

For example, when a condensing agent prepared in a weight ratio of potassium hydroxide 10 / potassium carbonate 90 is used and reacted at 130 ° C., it reacts up to about 99 to 100% in 3 hours,
On the other hand, when a condensing agent prepared in a weight ratio of potassium hydroxide 20 / potassium carbonate 80 is used, the condensation reaction is almost completed at 110 ° C for 5 hours.

In the method of the present invention using the above-mentioned specific reaction medium and condensing agent, the condensation reaction of halonitrobenzene and aminophenol proceeds efficiently to selectively produce monoamino / mononitro / diphenyl ether. You can

In order to obtain monoamino / mononitro / diphenyl ether from the reaction mixture produced by the condensation reaction according to the present invention, it can be easily separated and taken out by a separation method such as distillation, extraction, crystallization and the like.

The monoamino / mononitro / diphenyl ether in the reaction mixture may be used as it is in the reaction mixture or after the by-produced alkali metal halide is separated.
It can be reduced with hydrogen in the presence of a catalyst such as palladium or platinum to give diamino diphenyl ether.

Therefore, according to the method of the present invention, para-chloronitrobenzene and meta-aminophenol are subjected to a condensation reaction to produce 3-amino-4-nitrodiphenyl ether, which is reduced as described above and useful as an aromatic polyamide raw material. It also becomes possible to efficiently produce 3,4′-diaminodiphenyl ether.

[0027]

According to the method of the present invention as described above, the desired amino diphenyl ether can be efficiently produced without the problems of the conventional method.

[0028]

EXAMPLES The present invention will now be described in detail with reference to examples, but these are for explaining the present invention and the present invention is not limited to these examples.
In the examples, para-chloronitrobenzene in the reaction mixture, which represents the yield (selectivity) of 3-amino-4-nitrodiphenyl ether (hereinafter referred to as 3,4'-ANPE) and the conversion rate of aminophenol. The residual rate (ratio to 3,4′-ANPE produced) is a value obtained by gas chromatographic analysis.

[0029]

Example 1 (A) Preparation of condensing agent: commercially available special grade potassium carbonate (purity 9
(9.5%) 63 g and commercially available special grade potassium hydroxide (purity 8
5%) 7 g were mixed and pulverized, heated to 100 to 150 ° C., allowed to stand for 1 hour, then stirred and mixed and dispersed with a stirring rod at that temperature, and then the obtained mixture was heated to 200 ° C. for 1 hour. Bake for 4 hours, raise to 450 ° C, and burn for 5 hours
A condensing agent was prepared by drying.

(B) Condensation reaction: In a 1-liter four-necked flask equipped with a stirrer and a thermometer, 35 g of the condensing agent prepared as described above, 350 ml of dehydrated N, N-dimethylformamide, 55 g of meta-aminophenol and 88 g of para-chloronitrobenzene were charged, and stirring was continued at a temperature of 130 to 135 ° C for 3 hours.
At this point, a part of the reaction solution was taken and analyzed by gas chromatography. As a result, the amount of para-chloronitrobenzene remaining in the reaction system was determined to be 3-amino-4'-nitrodiphenyl ether (hereinafter 3,4). Called'-ANPE)
Was 0.15%. In addition, 3,4'-ANP
The yield of E was 99.0 mol% based on meta-aminophenol.

(C) Reduction reaction (synthesis of 3,4'-diaminodiphenyl ether): 3,4 'produced as described above
After cooling the reaction mixture containing ANPE at room temperature, the by-produced potassium chloride was removed by filtration, and 0.2 g of 5% Pd / C catalyst was charged into the autoclave and the hydrogen pressure was applied to the reaction mixture. 2 kg / cm ² G, reaction temperature 98 ° C., 3
Hydrogen reduction was carried out for an hour.

After the reaction was completed, the reaction solution was cooled to room temperature, the catalyst was filtered off, and the concentration of the produced 3,4'-diaminodiphenyl ether contained in the filtrate was analyzed and quantified by gas chromatography. As a result, the yield of 3,4′-diaminodiphenyl ether based on meta-aminophenol was 9
It was 8.5%.

[0033]

Examples 2 to 5 Example 1 (A) (B) is the same as Example 1 (A) except that the composition and amount of the condensing agent and the reaction temperature and time are changed as shown in Table 1 below. ) (B) same method,
Reaction was performed under the conditions to synthesize 3,4′-ANPE. The results are shown in Table 1. The "P-CN residual ratio" shown in Table 1 is the ratio of para-chloronitrobenzene contained in the reaction mixture to 3,4'-ANPE produced.

[0034]

[Comparative Examples 1-5] Example 1 (A) (B), except that the composition and amount of the condensing agent, the reaction temperature and time are changed as shown in Table 2 below. ) (B) same method,
The experiment was conducted under the conditions. The results are shown in Table 2.

[0035]

[Table 1]

[0036]

[Table 2]

Claims (5)

[Claims] 1. A method for producing an amino diphenyl ether by subjecting a halonitrobenzene and an aminophenol to a condensation reaction in a reaction medium, wherein an aprotic organic polar medium is used as a reaction medium and a dehalogenating condensing agent is used. A method for producing amino diphenyl ether, which comprises conducting a condensation reaction using a condensing agent composed of an alkali metal hydroxide and an alkali metal carbonate. 2. The aprotic organic polar medium is N, N-
The production method according to claim 1, which is at least one selected from dimethylformamide, N, N-dimethylacetamide, and N-methyl-2-pyrrolidone. 3. A condensing agent comprising an alkali metal hydroxide and an alkali metal carbonate forms a mixture of both compounds at 150 ° C.
The manufacturing method according to claim 1 or 2, wherein the manufacturing method is performed at the above temperature. 4. Para-nitrochlorobenzene is used as the halonitrobenzene and meta- is used as the aminophenol.
The method according to claim 1, 2 or 3, wherein aminophenol is used. 5. A condensation reaction of para-halonitrobenzene and meta-aminophenol in an aprotic organic polar medium in the presence of a dehalogenating condensing agent consisting of an alkali metal hydroxide and an alkali metal carbonate, The production method according to claim 1, wherein 3-amino-4-nitro diphenyl ether is produced, and then hydrogen reduction is carried out to obtain 3,4'-diamino diphenyl ether.