JPS591450A - Manufacture of o-phenylenediamine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to a novel process for the production of 0-phenylenediamine useful as an intermediate for the production of pharmaceutically active compounds and plant protection agents.

(Summary of the Invention) More specifically, the present invention starts from a compound represented by the following formula (1), X (wherein X represents hydrogen or chlorine), The present invention relates to a method of reducing hydrogen to hydrogen or a hydrogen-containing gas in the presence of a catalyst to obtain the desired final product.

PRIOR ART According to known methods, 0-phenylenediamine is generally produced by reducing 0-nitroaniline.

The reduction is carried out in an aqueous medium using iron, zinc or tin as the reducing agent (ViQnnacker-Küchler).
-Kichler): Kemiai technology
ologial, 742-748, Muszak
i Konyvkiado, Ptapes), 1962
], or sodium sulfide solution (FIAT Fina
l Repart 41313).

According to a more recent publication, catalytic hydrogen of O-nitroaniline 11. In this case, it is done by.

In the vapor phase, in the presence of steel [Brown-Carrick: J, Am, Soc, 41
．． 439 'l Moshikke Fuller in the presence of an earth-based palladium catalyst (British Patent No. 1,077,920), Father used Raney nickel as a catalyst (C
hem.

Zvesti 2, 114 (1948)] or using palladium or platinum on a carrier (published German Patent Application No. 2,461,615, U.S. Pat. No. 3,230,259). It will be done.

O-phenylene diamine u can also be prepared by reducing o-dinitrobenzene, but this starting material fIi cannot be practically used on an industrial scale.

The production of 0-phenylenediamine by ammonia decomposition of o-dichlorobenzene is patented in Japan (Patent Specification No. 77).
-95,615 to 77-95,617), and in this method, 20
Ammonia decomposition takes place at 0°C.

350°C in the presence of oxides of Mg, Sr and Zn.

The amino ratio of aniline to Q-7 ethylene diamine can be carried out at 300-400 bar, but the yields are moderate in this process (published German Specification No. 2,114). , No. 170).

Non-catalytic reduction of 0-nitroaniline is disadvantageous because it produces large amounts of by-products and waste water, and this problem is difficult to solve. The eight vapor phase process of the catalytic process is carried out at temperatures in excess of 250°C, and temperatures can be increased even higher if high pressures are used to accelerate the hydrogenation reaction.

Discontinuous liquid phase processes using suspended catalysts have been carried out almost exclusively. According to this method, 0-nitroaniline is dissolved in a suitable organic solvent (aromatic hydrocarbon, ester or alcohol), the catalyst is suspended in solution and hydrogenation is carried out under vigorous stirring. Implementation of these processes on an industrial scale requires recovery of substantial Ti solvent.

0-Nitroaniline is an intermediate that is prepared using many reaction steps, and therefore the most valuable directions for preparing 0-phenylenediamine are starting from benzene as the starting material, or starting with This method uses intermediates (chlorobenzene, nitrobenzene) and further steps to derive the desired final product. A common drawback of these methods to obtain O-phenylenediamine via L7 through 0-nitroaniline is that large amounts of p - Intermediates are also formed and the yield is reduced due to this by-product.

No. 175,397, No. 175,397, for producing 0-phenylenediamine by nitroconversion, then amination, and catalytic hydrogenation of p-dichlorobenzene.
The method described there avoids the above-mentioned drawbacks and does not produce any by-products.

Methods to prepare 0-phenylenediamine EL by other routes without 0-nitroaniline have not been widely practiced due to the unavailability of starting materials, the need for reduced reaction conditions, and the low yields. No 0 As an industrial method, amino acid and 0-chloro-nitrobenzene are used. -The reduction of nitro-niline is the most widely practiced. In this process, 'ri,o-chloronitrobenzene is formed as an isomer along with p-chloronitrobenzene, and the utility of this process therefore depends on the availability of p-chloro-nitrobenzene. If this issue is resolved.

O-phenylenediamine can be advantageously prepared in IB by this method.

As a result of a detailed study of the state of the prior art, the inventors found that among the known techniques, 0
It was concluded that a process based on the catalytic reduction of 2-nitro-glychloro-aniline and 2-nitro-glychloro-aniline prepared from p-dichlorobenzene is the most advantageous17.

In the experiments of the inventors, the inventors, etc., unexpectedly.

40-90%, preferably 50-6%, than in organic media.
Preferably hydrogen f in an aqueous medium containing ammonia of coefficient 0
I found out that it is possible to do this. 40% saliva) An aqueous solution containing a lot of ammonia is 100″C″ in %
, at higher temperature, forms a homogeneous reaction mixture with the organic reactants, i.e. compounds of general formula (1) where X is hydrogen or chlorine, and 30% ammonia, 30% water and about 20% 2-di A mixture containing 4-chloroaniline.

At temperatures above 100° C., a single homogeneous liquid phase is formed. Moreover, since the 7-ammonium ensures a constant pH in the medium, its presence has a positive influence on the activity of the reactivated palladium catalyst. When the hydrogen ratio is performed by hydrogen decomposition of the halogen, the large excess of ammonia absorbs the liberated hydrochloric acid and simultaneously keeps the formed salt 1 hyammonium by-product in solution. If organic solvents are used, salts will precipitate.

For this reason, a considerable f! t# It will be difficult. Excess ammonia can be easily evaporated off from the hydrogen mixture at temperatures above 100°C, and upon cooling, o-phenylenediamine precipitates as crystals from the remaining aqueous solution, while ammonium chloride remains in solution. remain in the The separation efficiency of 0-phenylenediamine and ammonium chloride by-products can be further increased by extraction methods. Separation by extraction can also be carried out without the preceding crystallization, in which case the separated o-phenylenediamine solution and salt 1-hyammonium solution are processed further.

Furthermore, the use of aqueous ammoniacal media provides additional important advantages. Ammonia decomposition of the compound represented by the following general formula (Ill-I (in the formula, X represents hydrogen or chlorine) occurs, and only the arsenic compound of general formula (1) is produced. This ammonia decomposition must be carried out in the presence of an excess amount of ammonia. The compound of general formula If the production and the production of the compound of general formula (1) by ammonia decomposition are carried out in conjunction, it is not necessary to separate the compound of general formula (1).

After the amine ratio reaction, a mixture of ammonia, water, a compound of general formula (1) and a salt Its ammonium by-product is
The compound of general formula (1) is directly introduced into a hydrogen reactor, where the compound of general formula (1) is reacted with a hydrogen ratio by adding an aqueous suspension of hydrogen ratio catalyst, introducing hydrogen gas, and keeping the reaction mixture homogeneous. It can be converted to 0-phenylenediamine. The combination of these two stages has an essential technical advantage from the point of view that 0-phenylenediamine can be produced most advantageously with this higher amino ratio stage and hydrogen ratio stage.

According to the invention, in an apparatus equipped with a stirrer.

A homogeneous mixture is formed by mixing the compound of general formula (1) with an aqueous solution containing 50-60% ammonia at a temperature of 100''C under pressure.

l 5-10% palladium catalyst 0.05-2% on activated carbon
~10 added as a waterborne suspension, and 100-160
The hydrogen ratio is carried out by introducing hydrogen gas or a hydrogen-containing gas under a pressure of 60 to 200 par. Under such conditions, conversion rates of greater than 98% are achieved within 20-60 minutes. Hydrogen 111 during high temperature. Excess ammonia is removed by evaporation from the reaction mixture, catalyst tF is removed, and 1. 80% or more of 0-7 enylenediamine is collected from the 11-solution by cooling, crystallization and CFIl&.

O-phenylenediamine is separated from the mother liquor by solvent extraction (1). Ammonium chloride remains in the aqueous solution,
It can be separated into crystalline form by evaporation. thus,
Ammonium chloride is separated in an industrially usable form;
On the other hand, the water is freed from inorganic salts which would have a detrimental effect on the environment.

For solvent extraction, hydrocarbons for chlorine such as chloroform, 1,2-dichloroethane-IJ chloroethylene, perchloroethylene 4L<Ul, ].

2-)! Chloroethane, benzene, toluene, ether, or ester can be used to remove the ammonia by evaporation.Also, if the extraction is carried out without performing the crystallization of 0-phenylenediamine, the crystallization or evaporation may be performed. All 0-phenylenediamine is separated from the solvent phase.

Hydrogen can be produced discontinuously in one reactor equipped with two stirrers, or discontinuously in a cascade reactor in which these reactors are interconnected. It can be carried out continuously using a reactor. The catalyst is kept in suspension in the reactor by mechanical stirring or gas stirring. Ammonia is recovered from the gas that has passed through one reactor by water harvesting and washing under pressure. Hydrogen-containing ammonia synthesis gas can also be used instead of hydrogen.

According to a preferred embodiment of the invention, the hydrogen ratio is 11-connected to the amine ratio reaction. In this case, 1 of the general formula (take)
The 1Z compound was mixed with an aqueous solution containing 70-90% ammonia to form a homogeneous mixture, and the 180
Perform the amine ratio at a temperature of ~220°C. Amine ratios can be made batchwise or continuously. Cooling the reaction mixture to 100-160 °C for 20-40 minutes of reaction;
It is then introduced into a hydrogen ratio reactor where the catalyst is suspended and hydrogen is introduced as described above.

The operation of a continuous experimental device that combines the addition of amino ratio and hydrogen ratio will be explained with reference to the flowchart shown in the drawing.

o-90ronitrobenzene or fx2,5-dichloro-
Nitrobenzene is fed by pump 6 from vessel 2, and concentrated aqueous ammonia solution is fed from vessel 3 by pump 7. After mixing, the homogeneous liquid phase reaction mixture is fed to a tube reactor 9 for amino ratio, where the amino ratio is carried out at 200-220°C. The reaction mixture containing ammonia, water, ammonium chloride, and o-nitroaniline or 2-nitro-4-chloroaniline was heated in a heat exchanger to
Cool to 0° C. and drain into bottom 1 of hydrogenation reactor 11. In the same part of this reactor there is a pump 8 from the feed vessel 4.
Bacdium on activated carbon catalyst is introduced from r. Also, hydrogen gas is fed to the bottom of the hydrogen ratio reactor under a pressure of 60 to 200 bar. The reaction mixture from the hydrogen ratio reactor 11 enters the separator 12 (where the ammonia-saturated hydrogen gas is separated from the liquid phase containing the catalyst. The gas is introduced into the absorber 13, which is pressurized. The ammonia is then washed away with water. The recovered ammonia aqueous solution can be used once after concentrating it with fresh ammonia. The liquid phase from the separator 12 is:

The ammonia is continuously introduced into the ammonia heater 14. Ammonia gas from the ammonia heater is introduced into the absorber 13, where it is absorbed. By filter 17.

The catalyst is removed from the hot liquid phase discharged from the ammonia heater 14 and the saturated solution containing 0-phenylenediamine and ammonium chloride is fed to the countercurrent extractor 15 where it is fed by the feed pump 5. O-phenylenediamine is extracted with a solvent. Ammonium chloride only
A solution containing i is introduced into the container 19. A hot solvent solution saturated with 0-phenylenediamine is fed to crystallizer 16 where it is cooled. The final product, 0-phenylenediamine, is filtered through a filter 18. Contain the product 21
to collect. The mother liquor passed through the p filter 18 has a concentration of about 2 to 5
- Contains phenylenediamine, all containers 20
and extract again if desired.

This invention will now be explained in more detail by way of example.

However, this does not limit the scope of the invention.

Example 1 13.8 g of 0-nitroaniline was weighed and placed in a high-pressure container with a stirrer and heated, after which the container containing the 0-nitroaniline was sealed.

18I of water is added and then 28g of liquid ammonia is added under pressure from a feed vessel. Heat the contents of the container to 100° C. with stirring. 40 ml of 10% palladium on activated carbon catalyst is suspended in 109 g of water and this suspension is injected into a 0.2 dm3 hydrogen ratio reactor with a heating jacket and gas dispersion device. The catalyst is kept in suspension by gas stirring. The temperature of the reactor was adjusted to 130°C, and the pressure was adjusted to 1
The mixture of 0-nitroaniline, ammonia and water was heated to 100% hydrogen by pressurizing the top with nitrogen.
Pump into the reactor. After 40 minutes, stop the water flow,
Then, ammonia is removed by evaporation throughout the /<A/b. The contents of the reactor are then removed 1 and the catalyst is removed. Crystals of sy from hot saturated aqueous solution 0-
Collect the phenylenediamine in a furnace. It has a melting point of 101°C after drying. Evaporation of the mother liquor gives a further 2.6 g of product. The melting point is 98°C.

Example 2゜ At 100° C. as described in Example 1.

17.18 to 2-nitro-4-chloroaniline in 2.9
1! of water and 28 g of liquid ammonia.

The same hydrogen as described in Example 1 [1
A suspension of 100 μm of a 0-group palladium catalyst suspended in 10.9 μm of water is added. After heating with hydrogen for 60 minutes, the pressurization was stopped in the same way as in 1, the ammonia was boiled off, the catalyst was removed, and 8.5 g (Do-phenylenediamine) was removed from the solution. 20 mg of the mother liquor was Extract with chloroform. Evaporation of the chloroform solution yields an additional 2 g of O-
Obtain phenylenediamine. 5 g of crystalline ammonium chloride are separated by evaporating the aqueous solution.

Example 3゜15.8 in a stainless steel 120og autoclave
g(7) Add o-chloro-nitrobenzene.

Add 30g liquid ammonia and 8I water.

Heat the autoclave to 220°C while shaking.

In the same hydrogen ratio reactor as in Example 1, 20 ml of activated carbon in water
% palladium catalyst somg suspension. Start the flow of hydrogen7. The temperature is adjusted to 140° C. and the pressure to 100 bar. The two reactor mixtures are then pumped into the hydrogenation reactor. After 40 minutes, stop the gas flow and remove the ammonia boiling mass [7. The catalyst is stripped from the hot reaction mixture and the P#L is extracted five times with 20 tpte each of benzene. By evaporating the benzene solution, the melting point is 99℃.
10.2 g of 0-phenylenediamine are separated.

The amino ratio of Example 4 and the hydrogen ratio described in Example 1 are as follows: 19.3 g of 2.
Performed using 5-dichloro-nitrobenzene. 30 g of liquid ammonia and 8 g of water are used for the complete ratio. Amino ratio is carried out for 20 minutes at a temperature of 200°C. A suspension of 200 μl of 10% palladium on activated carbon in water of 20.9 is used in the hydrogen ratio step. Under a pressure of 80 bar, 1
Perform the hydrogen ratio for 60 minutes at 20°C. The reaction mixture from which ammonia has been removed is extracted with 1,2-dichloroethane after removing the catalyst. Extract 3 times with 20 ynl of solvent each. By evaporating the solvent, o-
Phenyl diamine 10.3 #t-6. Evaporation of the aqueous phase yields 1o, tII ammonium chloride.

EXAMPLE 5 Using the apparatus according to the flowchart of the drawing, 2300 #/hr of 80% aqueous ammonia solution of 0-phenylene diarolonitrobenzene is fed to feed pumps 6 and 7, respectively. Cool the mixture from the reactor to 130 °C [2,
It is pumped into a hydrogen ratio reactor 11 whose temperature is adjusted to 130° C. by hot water in a heating jacket. To the reactor, 1100 ml of a suspension of 817 hours of 10-chipalladium catalyst on activated carbon in water is added via pump 8. The reactor pressure is 150 bar. Ammonia is removed from the liquid phase leaving the separator 12 in a heater 14 and then in a filter 17.
The catalyst is removed at and recycled for repeated use.

A hot saturated solution of the product 0-phenylenediamine was heated to 150
Extract with 0xe/h 1.2-)lichloroedane in the same flow rate subsequent extractor 15. Crystal can 16 and p filter 18
530 g/hour of dry 0-phenylenediamine was obtained.

The melting point is 100°C. Collect the ammonium chloride aqueous solution in container 19. 280 from a solution of 1000 by evaporation
Ammonium chloride of I is obtained as crystals.

Example 6: In the apparatus of Example 5, 820.9/h of 0-chloro-nitrobenzene, 23001? /R 80% ammonia aqueous solution,
1100 ml of 5% palladium catalyst on activated carbon in water 69
/h, and 1500me/h recycled 1,2-dichloroethane extractant, temperature t220 in the amino ratio reactor.
℃, and the temperature in the hydrogenation reactor was 150℃,
Proceeding as in Example 5 with a pressure of 150 bar, 54
311/h of 0-phenylenediamine are obtained. melting point 10
It is 1℃.

(Advantages of the method of the present invention) (1) Since an ammonia aqueous solution is used, the method can be carried out without using a soluble solvent.

(2) Ammonia is necessary for the hydrogen specific decomposition of chlorine and for adjusting the pH of the reaction mixture, and the presence of ammonia makes it possible to obtain a homogeneous reaction mixture.

(3) In the presence of ammonia, ammonium chloride is produced as a result of the hydrogen specific decomposition of chlorine, which is a useful by-product, and the process does not pose environmental problems.

(4) In this invention, the compound of general formula (1) (X=H or C/) produced by the amino ratio does not need to be separated to round the hydrogen ratio and then dissolved in a solvent again.

(5) In the method of the present invention, the hydrogenation step, which has been carried out discontinuously, can advantageously be carried out continuously.

[Brief explanation of drawings]

The drawing is a flowchart for the continuous implementation of the method of the invention. In the figure, 9 is an amino ratio reactor, a jlVi hydrogenation reactor, 12 is a separator, and 13 is an absorber. 14 is an ammonia heater, and 15 is a cocurrent extractor. 16 is a crystallizer and an 18-filter. Patent Applicant Magyar Asbanyolai Esfoldogaz Kisserretei Intezet Special Patent Attorney Patent Attorney Akira Aoki Patent Attorney Kazuyuki Nishidate Patent Attorney Mune Fukumoto Patent Attorney Akira Yamaguchi Page 1 Continued 0 Author Yozsef Batholii Beszprem Jozsev Ní Utsa, Hungary 3/0 Inventor: Lajos Kisgelgelly, Várparota Horakutele, Hungary 2 0 Inventor: Gyula Kinczes, Beszprem Markus Kuu Utsa, Hungary 11 [Phase] Inventor Inventor: Sandor Yellen, Budapest, Hungary 37 0 Inventor: Eremel Furtak, Budapest Polgar Utsa, Hungary 3

Claims (1)

[Claims] 1. 30 to 70 grams of ammonia and 10 to 50 grams of water;
and the hydrogen ratio of the primary formula (1) in the presence of a catalyst. (In the formula, X is hydrogen or chlorine.) The compound represented by
A process for producing 0-phenylenediamine, characterized by removing the catalyst and collecting the reaction product by solvent extraction and/or crystallization. 2. Hydrogen ratio of 40-50% ammonia and 30-40%
% of water. 3. The method according to claim 1, wherein the hydrogen ratio is continuously determined. 4. The compound represented by formula (1) is converted into the first-order general formula (1)
, I (wherein X is hydrogen or chlorine)
The method described in any one of paragraphs.