JPH0240057B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention aminates 1,4-dibromobenzene to produce 1,4-diaminobenzene and 1,4-diaminobenzene, which are intermediate raw materials for synthetic fibers, dyes, antioxidants, etc. The present invention relates to a method for synthesizing 4-bromoaniline, which is an intermediate raw material for dyes, synthetic resins, etc.

(Prior art) In Japanese Patent Publication No. 56-40145, aromatic dihalides are mixed with 170 to 240 moles of aromatic dihalide using a copper compound as a catalyst in the presence of water in an amount of 2 times or more of the aromatic dihalide.
Discloses a method for producing aromatic diamines by amination with ammonia at .degree. At this time, if the amount of water is less than 2 moles, the contact between the reaction raw materials and the catalyst etc. will be insufficient, and the reaction will not only not proceed smoothly, but also the amount of by-products will increase and the yield will decrease. It is also stated that the reaction does not proceed at temperatures below 160°C.

In JP-A-59-13750, halogenated benzene is aminated with an aqueous ammonia solution in the presence of copper, a complexing agent for copper, and an 8-hydroxyquinoline derivative to form a halogenated aniline (specifically, 3,5-dichloro discloses a method for producing aniline).

U.S. Pat. No. 3,422,145 discloses a method for aminating 1,6-dibromohexane in liquid ammonia and improving the selectivity of 1,6-diaminohexane by dissolving a large amount of ammonium bromide. Discloses that.

(Problems to be solved by the invention) In the amination of halobenzene in an ammonia-water system, the reaction does not proceed at temperatures below 160°C;
It has been disclosed that this method requires a high temperature (Japanese Patent Publication No. 56-40145). Amination of halobenzene at such high temperatures is difficult to put into practical use because the ammonia water containing by-product ammonium halide and the copper compound of the catalyst is highly corrosive. Furthermore, due to the high temperature and coexistence of water, heavy substances and phenols are produced as by-products, which not only lowers the yield of the aminated product but also makes recovery and purification of the aminated product extremely difficult. Furthermore, diaminobenzene, an amination product, has poor thermal stability and high water solubility, so recovery requires expensive methods such as multistage extraction.

(Means for Solving the Problems) The present inventors investigated a method for selectively aminating 1,4-dibromobenzene at a low temperature, which is advantageous in terms of selecting the material of the reactor. By reacting benzene with ammonia in the presence of at least one selected from copper and copper compounds under mild conditions of 30°C or higher and lower than the critical temperature of ammonia and under substantially anhydrous conditions, 1.
We have discovered a method for aminating 4-dibromobenzene. Furthermore, at that time, the present inventors have discovered that by coexisting an inert organic solvent that does not substantially dissolve 1,4-diaminobenzene, various advantages described below can be added, and the present invention has been completed.

That is, the present invention provides a method for aminating 1,4-dibromobenzene in a liquid phase using ammonia under substantially anhydrous conditions using at least one selected from copper and a copper compound as a catalyst. , a method for aminating 1,4-dibromobenzene, characterized in that 1,4-dibromobenzene is aminated at a temperature of 30° C. or higher and lower than the critical temperature of ammonia, further comprising: , 4-diaminobenzene is coexisting with an inert organic solvent that does not substantially dissolve 4-diaminobenzene.

In the process of the invention, the ammonia is present as liquid ammonia or as a solution in an inert organic solvent that does not substantially dissolve the 1,4-diaminobenzene. In the latter case, if ammonia is added in an amount that is substantially below its saturation solubility in the inert organic solvent, the ammonia is present as a substantially inert organic solvent solution; When added in amounts above the saturation solubility, ammonia exists as a solution in an inert organic solvent as well as liquid ammonia.

In the amination reaction of the present invention, 2 moles of ammonia are consumed per gram of bromine atom of 1,4-dibromobenzene, and it is sufficient to use more than the theoretical amount of ammonia in the reaction. The molar ratio of ammonia in the liquid phase to 4-dibromobenzene is preferably 10 or more.

Amination of 1,4-dibromobenzene according to the method of the invention gives 1,4-diaminobenzene and/or 4-bromoaniline.
Since 1,4-dibromobenzene is sequentially aminated to 1,4-diaminobenzene via 4-bromoaniline, the amination conditions, temperature, time, whether or not to use a solvent, amount of solvent, etc. should be adjusted appropriately. One of the features of the present invention compared to the prior art is that the production ratio of 4-bromoaniline and 1,4-diaminobenzene can be appropriately selected by selection.

When 1,4-diaminobenzene is primarily produced by the method of the invention, it is preferred that the ammonia is present primarily as liquid ammonia.
Further, when it is desired to co-produce 4-bromoaniline and 1,4-diaminobenzene, it is preferable to carry out the process in the coexistence of an inert organic solvent that does not substantially dissolve 1,4-diaminobenzene. Furthermore, substantially 4-
If it is desired to produce only bromoaniline, it is preferable that ammonia be dissolved in an inert organic solvent that does not substantially dissolve 1,4-diaminobenzene.

When amination is carried out in the presence of an inert organic solvent that does not substantially dissolve 1,4-diaminobenzene, 1,4-diaminobenzene can be easily separated from 4-bromoaniline and 1,4-dibromobenzene by solid-liquid separation. It can be separated into A mixture of 4-bromoaniline and 1,4-dibromobenzene can be easily separated, for example, by distillation or extraction.
The mixture may be returned to the amination reaction step.
In order to separate 1,4-diaminobenzene from 4-bromoaniline and 1,4-dibromobenzene, an inert organic solvent that does not substantially dissolve 1,4-diaminobenzene may be added after the amination reaction step. However, when 4-bromoaniline and 1,4-dibromobenzene are to be returned to the amination reaction step, it is preferable to add them from the amination reaction step, as this simplifies the process and is also preferable from the standpoint of separation and recovery.

In the method of the present invention, copper and copper compounds are effective as catalysts for amination reactions. Examples of copper compounds include halides such as bromides,
There are inorganic acid salts such as sulfates, organic acid salts such as succinates, oxides, hydroxides, and complexes of copper compounds with ammonia. The copper compound is preferably a monovalent copper compound, and cuprous bromide is particularly preferred. The amount of copper and copper compound used is preferably 0.001 to 5 gram atoms, more preferably 0.005 to 1.5 gram atoms, in terms of copper element per 1 gram mole of 1,4-dibromobenzene. One or more of the copper and copper compounds used in the method of the present invention may be supported on a carrier. When a carrier is used, alumina, silica, etc. are preferable as the carrier.

In the method of the present invention, the inert organic solvent that does not substantially dissolve 1,4-diaminobenzene is 1,4-diaminobenzene.
It is a solvent for 4-dibromobenzene and also dissolves 4-bromoaniline. Inert organic solvents that do not substantially dissolve 1,4-diaminobenzene include:
Organic solvents with low polarity and hydrogen bonding properties and inert under the amination reaction conditions are suitable, such as saturated hydrocarbons, preferably acyclic saturated hydrocarbons,
These include fluorinated saturated hydrocarbons. Specific examples include butane, pentane, hexane, heptane,
Octane, nonane, decane, undecane, dodecane, tridecane, tetradecane, hexadecane,
There are one type or a mixture of two or more of tetradecafluorohexane and tetradecafluoromethylcyclohexane, including pentane, hexane, heptane, octane, nonane, decane, undecane, dodecane, tridecane, tetradecane, tetradecafluorohexane, and tetradecafluoro. One or more types of methylcyclohexane are preferred.

In the method of the present invention, the reaction temperature is 30°C or higher,
Although it is below the critical temperature of ammonia, the reaction proceeds rapidly at 30°C or higher, and there are few side reactions below the critical temperature of ammonia, so the above temperature range is preferable. A temperature of 50°C to 115°C is preferred.

In the method of the present invention, the reaction pressure is 10-115
Kg/cm ² G is preferable, and 20 to 80 Kg/cm ² G is more preferable.

(Effects of the Invention) Since the method of the present invention carries out the amination reaction in a substantially anhydrous state and under mild conditions, the reaction proceeds selectively, and there is no possibility of equipment corrosion, so expensive materials are not required. does not require.

Since the method of the present invention is carried out in a substantially anhydrous state, it is easy to separate and recover the aminated product and to recover and reuse the catalyst.

In the method of the present invention, when coexisting an inert organic solvent that does not substantially dissolve 1,4-diaminobenzene, 1,4-diaminobenzene can be used more easily than 4-bromoaniline and 1,4-dibromobenzene. It can be separated into Both 1,4-diaminobenzene and 4-bromoaniline are desired to be of high purity, and complete separation of the two is strongly desired, not only when both are co-produced, but also when one is primarily produced. However, since both have poor thermal stability at high temperatures, it is difficult to separate and purify them by known methods such as distillation, and the effects of the present invention are significant.

(Example) Example 1 1,4-dibromobenzene 5g, cuprous bromide
Put 1.5 g and 40 ml of liquid ammonia into a stainless steel autoclave with an internal volume of 200 ml and a stirrer, and heat at 90℃.
The pressure was maintained at 51 kg/cm ² G for 3.5 hours while stirring.
After the reaction, the autoclave was returned to normal temperature and pressure, and the organic matter was extracted with tetrahydrofuran.
m, 200°C). 1,4-diaminobenzene was obtained with a yield of 99 mol%.

Example 2 Amination was carried out under the same conditions as in Example 1, except that the reaction temperature was changed to 70° C. and the pressure was changed to 30 Kg/cm ² G.
Yield of 1,4-diaminobenzene was 92 mol%, 4-
Bromoaniline was obtained with a yield of 4 mol%.

Example 3 The reaction was carried out under the same conditions as in Example 1, except that the reaction temperature was changed to 54° C., the pressure was changed to 21 Kg/cm ² G, and the reaction time was changed to 5.5 hours. The rate of change of 1,4-dibromobenzene is
The yield of 1,4-diaminobenzene was 26 mol%, and the yield of 4-bromoaniline was 45 mol%.

Example 4 1,4-dibromobenzene 15g, cuprous bromide
0.09 g and 40 ml of liquid ammonia were placed in the same autoclave as in Example 1, heated to 111°C and 70 Kg/cm ² G.
Keep stirring for 4.5 hours. Conversion rate of 1,4-dibromobenzene 68%, yield of 1,4-diaminobenzene 20 mol%, yield of 4-bromoaniline 46
It was mol%.

Example 5 1,4-dibromobenzene 5g, cuprous chloride
1.5g of liquid ammonia and 40ml of liquid ammonia were placed in the same autoclave as in Example 1, heated to 100℃ and 60Kg/cm ² G.
Keep stirring for 4.5 hours. The conversion rate of 1,4-dibromobenzene was 99%, and the yield of 1,4-diaminobenzene was 95 mol%.

Example 6 5 g of 1,4-dibromobenzene, 1 cuprous bromide
Put 40 ml of g, n-nonane into the autoclave used in Example 1, connect a cylinder filled with liquid ammonia to the autoclave, immerse the autoclave in a dry ice/ethanol bath, introduce liquid ammonia, close the autoclave, and ℃
While stirring, raise the temperature to (autogenous pressure 60Kg/cm ² G).
It was kept for 4.5 hours. Return the autoclave to room temperature and pressure, and transfer the reaction product to a gas chromatograph (PEG20M 2m column, column temperature 200℃) using the following procedure.
It was analyzed in When the reaction product was separated into solid and liquid and the liquid was analyzed, it was found that 0.7 g of 1,4-dibromobenzene, 4
- Contains 0.73g of bromoaniline. The liquid extracted from the solid with tetrahydrofuran contains 1,4
-Contained 1.51g of diaminobenzene (1,
4-dibromobenzene conversion rate: 86%, 4-bromoaniline yield: 20 mol%, 1,4-diaminobenzene yield: 65 mol%).

Example 7 5.1 g of 1,4-dibromobenzene, 1 g of cuprous bromide, and 40 ml of n-nonane were placed in an autoclave with an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the mixture was heated to 100°C with stirring. ,60Kg/ ^cm2G
It was kept for 7 hours. 1,4-diaminobenzene was obtained with a conversion rate of 95% of 1,4-dibromobenzene and a yield of 86 mol% based on the charged 1,4-dibromobenzene, and 4-bromoaniline was obtained with a yield of 9 mol%. Obtained.

Example 8 5 g of 1,4-dibromobenzene, 1 cuprous bromide
Pour 40 ml of 3-methylpentane into an autoclave with an internal volume of 200 ml, introduce ammonia in the same manner as in Example 6, and then raise the temperature to 100°C and the pressure to 61 Kg/cm ² G.
It was kept for 4 hours with stirring. Conversion rate of charged 1,4-dibromobenzene: 67%, charged 1,4-
1,4- with a yield of 41 mol% based on dibromobenzene.
Diaminobenzene was obtained with a yield of 26 mol% of 4
- Bromoaniline was obtained.

Example 9 5 g of 1,4-dibromobenzene, 1 cuprous bromide
40 ml of n-hexane was charged into an autoclave having an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the autoclave was maintained at 100° C. and a pressure of 60 kg/cm ² G for 5 hours with stirring. 1,4-diaminobenzene was obtained with a conversion rate of 60% of the charged 1,4-dibromobenzene and a yield of 45 mol% based on the charged 1,4-dibromobenzene, and 4-bromobenzene was obtained with a yield of 15 mol%. Aniline was obtained.

Example 10 5 g of 1,4-dibromobenzene, 1 cuprous bromide
Pour 40 ml of g,n-pentane into an autoclave with an internal volume of 200 ml, introduce ammonia in the same manner as in Example 6, and then heat at 100°C with stirring at a pressure of 60 kg/cm ²
I kept it at G for 4 hours. 1,4-diaminobenzene was obtained with a conversion rate of 53% of 1,4-dibromobenzene and a yield of 31 mol% based on the charged 1,4-dibromobenzene, and 4-bromoaniline was obtained with a yield of 22 mol%. Obtained.

Example 11 5 g of 1,4-dibromobenzene, 1 cuprous bromide
40 ml of g,n-dodecane was charged into an autoclave having an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the autoclave was maintained at 100° C. and a pressure of 60 kg/cm ² G for 6 hours with stirring. 13% of 1,4-dibromobenzene was converted, 1,4-diaminobenzene was obtained in a yield of 12 mol%, and 4-bromoaniline was obtained in a yield of 0.6 mol%.

Example 12 5 g of 1,4-dibromobenzene, 1 cuprous bromide
40 ml of n-heptane was charged into an autoclave having an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the autoclave was maintained at 100° C. and a pressure of 50 kg/cm ² G for 5 hours with stirring. 24% of the 1,4-dibromobenzene was converted, and 4-bromoaniline was obtained in a yield of 24 mol% based on the 1,4-dibromobenzene charged.

Example 13 5 g of 1,4-dibromobenzene, 1 cuprous bromide
40 ml of n-octane was charged into an autoclave having an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 7, the autoclave was kept at 100° C. and a pressure of 60 kg/cm ² G for 3.5 hours with stirring. 46% of 1,4-dibromobenzene was converted, and 1,4-diaminobenzene was obtained with a yield of 14 mol% based on the charged 1,4-dibromobenzene, and 4-bromoaniline was obtained with a yield of 32 mol%. was gotten.

Example 14 5 g of 1,4-dibromobenzene, 1 cuprous bromide
Pour 40 ml of 3-methylpentane into an autoclave with an internal volume of 200 ml, introduce ammonia in the same manner as in Example 6, and then raise the temperature to 100°C and the pressure to 55 kg/cm ² G.
Keep stirring for 3.5 hours. 20% of the 1,4-dibromobenzene was converted, and 4-bromoaniline was obtained in a yield of 20 mol% based on the 1,4-dibromobenzene charged.

Example 15 5 g of 1,4-dibromobenzene, 1 cuprous bromide
40 ml of g,i-heptane was charged into an autoclave having an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the autoclave was maintained at 100° C. and a pressure of 60 kg/cm ² G for 4 hours with stirring. 18% of the 1,4-dibromobenzene was converted, and 4-bromoaniline was obtained in a yield of 18 mol% based on the 1,4-dibromobenzene charged.

Example 16 1,4-dibromobenzene 5g, cuprous bromide
0.2 g of n-nonane and 40 ml of n-nonane were placed in an autoclave, and after introducing ammonia in the same manner as in Example 6, the mixture was heated to 100°C and a pressure of 60 kg/cm ² G with stirring.
It kept time. 4-bromoaniline was obtained in a yield of 16 mol% based on the charged 1,4-dibromobenzene, and 1,4-diaminobenzene was obtained in a yield of 3 mol%.

Example 17 5 g of 1,4-dibromobenzene, 1 cuprous chloride
40 ml of n-nonane was charged into an autoclave having an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the autoclave was maintained at 100° C. and a pressure of 60 kg/cm ² G for 3 hours with stirring. 31% of 1,4-dibromobenzene was converted, and 4-bromoaniline was obtained with a yield of 25 mol% based on the charged 1,4-dibromobenzene, and 1,4-diaminobenzene was obtained with a yield of 6 mol%. was gotten.

Example 18 1,4-dibromobenzene 5g, cupric bromide 2
40 ml of n-nonane was charged into an autoclave having an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the autoclave was maintained at 115° C. and a pressure of 78 kg/cm ² G for 3 hours with stirring. 12% of 1,4-dibromobenzene was converted, and 4-bromoaniline was obtained with a yield of 10 mol% based on the charged 1,4-dibromobenzene, and 1,4-diaminobenzene was obtained with a yield of 2 mol%. was gotten.

Example 19 5 g of 1,4-dibromobenzene, 1 cuprous oxide
40 ml of n-nonane was charged into an autoclave having an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the autoclave was maintained at 100° C. and a pressure of 60 kg/cm ² G for 3.5 hours with stirring. 10% of the 1,4-dibromobenzene was converted, and 4-bromoaniline was obtained in a yield of 10 mol% based on the 1,4-dibromobenzene charged.

Example 20 1,4-dibromobenzene 5g, cupric succinate
0.8 g of n-nonane and 40 ml of n-nonane were charged into an autoclave with an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the autoclave was maintained at 105° C. and a pressure of 65 Kg/cm ² G for 3 hours with stirring. 19% of the 1,4-dibromobenzene was converted, and 4-bromoaniline was obtained in a yield of 15 mol% based on the 1,4-dibromobenzene charged.

Example 21 1,4-dibromobenzene 5g, copper powder 1.2g,
40 ml of n-nonane was charged into an autoclave with an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the autoclave was maintained at 100° C. and a pressure of 60 Kg/cm ² G for 3.5 hours with stirring. 1,4-dibromobenzene
4-bromoaniline was obtained in a yield of 22 mol% and 1,4-diaminobenzene was obtained in a yield of 10 mol% based on the charged 1,4-dibromobenzene.

Example 22 2.5 g of 1,4-dibromobenzene, cuprous bromide
0.25 g, n-nonane 30 ml, and n-decane 10 ml were placed in an autoclave with an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the temperature was 100°C and the pressure was
It was kept at 60Kg/cm ² G for 4 hours with stirring. 1,
27% of 4-dibromobenzene was converted, and 4-bromoaniline was obtained with a yield of 20 mol% based on the charged 1,4-dibromobenzene, and 1,4-diaminobenzene was obtained with a yield of 3 mol%. It was done.

Example 23 Porous alumina was immersed in an ammonia aqueous solution of cuprous bromide (concentration of cuprous bromide: 0.86 g/cc), left overnight, over-separated, and dried at 120° C. for 5 hours. Contains 2.4 g of cuprous bromide/alumina catalyst, 5 g of 1,4-dibromobenzene, and 40 ml of n-nonane.
After introducing ammonia into a 200ml autoclave and introducing ammonia in the same manner as in Example 6, the temperature was 100℃ and the pressure was 60℃.
Kg/cm ² G for 4 hours with stirring. 1,4
-10% of dibromobenzene was converted, and 4-bromoaniline was obtained in a yield of 10 mol% based on the 1,4-dibromobenzene charged.

Example 24 2.5 g of 1,4-dibromobenzene, cuprous bromide
0.25 g, n-undecane 50 ml was placed in an autoclave with an internal volume of 200 ml, and after introducing ammonia by the same operation as in Example 6, the temperature was 102°C and the pressure was 63 Kg/cm ²
G and kept for 4.2 hours with stirring. 57% of 1,4-dibromobenzene was converted and the charged 1,4
-4-bromoaniline was obtained with a yield of 35 mol% based on dibromobenzene, and 1,4-bromoaniline was obtained with a yield of 22 mol%.
-Diaminobenzene was obtained.

Example 25 1,4-dibromobenzene 2.6 g, cuprous bromide
0.6g, n-heptane 70ml was charged into an autoclave with an internal volume of 200ml, and after introducing ammonia by the same operation as in Example 6, the temperature was raised to 100°C and the pressure was 59Kg/cm ² G.
It was kept for 6 hours with stirring. 34 mol% of 1,4-dibromobenzene changed, and the yield of 4-bromoaniline per 1,4-dibromobenzene charged was
It was 34 mol%.

Example 26 2.5 g of 1,4-dibromobenzene, cuprous bromide
0.25 g, n-decane 25 ml, and n-nonane 25 ml were placed in an autoclave with an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the mixture was heated at 100°C.
The pressure was maintained at 60 kg/cm ² G for 4 hours with stirring.
30% of 1,4-dibromobenzene was converted, and 1,4-diaminobenzene was obtained with a yield of 11 mol% based on the charged 1,4-dibromobenzene, and 4-bromoaniline was obtained with a yield of 19 mol%. was gotten.

Example 27 5 g of 1,4-dibromobenzene, 60 ml of liquid ammonia, 1.5 g of cuprous bromide, and 50 ml of n-nonane were charged into an autoclave with an internal volume of 200 ml, and heated at 100°C and a pressure of 59 Kg/cm ² G while stirring. It was kept for 3.5 hours.
33% of 1,4-dibromobenzene was converted, and 4-bromoaniline was obtained with a yield of 19 mol% based on the charged 1,4-dibromobenzene, and 1,4-diaminobenzene was obtained with a yield of 14 mol%. was gotten.

Example 28 5 g of 1,4-dibromobenzene, 60 ml of liquid ammonia, 2.5 g of cuprous bromide, and 50 ml of n-nonane were placed in an autoclave with an internal volume of 200 ml, and the mixture was heated at 100°C and under a pressure of 60 Kg/cm ² G while stirring. It was kept for 3.5 hours.
56% of the charged 1,4-dibromobenzene was converted, and 4-bromoaniline was obtained with a yield of 28 mol% based on the charged 1,4-dibromobenzene, and 1,4-bromoaniline was obtained with a yield of 28 mol%. Diaminobenzene was obtained.

Example 29 5 g of 1,4-dibromobenzene, 80 ml of liquid ammonia, 1.5 g of cuprous bromide, and 50 ml of n-nonane were charged into an autoclave with an internal volume of 200 ml, and heated at 100°C and a pressure of 59 Kg/cm ² G while stirring. It was kept for 3.5 hours.
55 mol% of 1,4-dibromobenzene changed,
27 mol% based on charged 1,4-dibromobenzene
4-bromoaniline was obtained with a yield of 28 mol%.
1,4-diaminobenzene was obtained in a yield of .

Example 30 1,4-dibromobenzene 5g, cuprous bromide
1.5 g of liquid ammonia, 20 ml of liquid ammonia, and 10 ml of tetradecafluorohexane were placed in an autoclave with an internal volume of 200 ml, and maintained at 100° C. and a pressure of 59 Kg/cm ² G for 2.5 hours with stirring. 10% of 1,4-dibromobenzene was converted, and 4-bromoaniline was obtained with a yield of 4 mol% based on the charged 1,4-dibromobenzene, and 1,4-diaminobenzene was obtained with a yield of 6 mol%. was gotten.

Example 31 1,4-dibromobenzene 5g, cuprous bromide
Charge 1.5g, 17ml of tetradecafluoromethylcyclohexane, and 40ml of liquid ammonia into an autoclave with an internal volume of 200ml, and heat to 65Kg/ ^cm2G at 100℃.
It was kept for 13.5 hours with stirring. Prepared 1,4-
4-bromoaniline was obtained with a yield of 1 mol% based on dibromobenzene, and 1,4-bromoaniline was obtained with a yield of 93 mol%.
Diaminobenzene was obtained.

Example 32 1,4-dibromobenzene 2.5 g, cuprous bromide
0.4 g of n-octane and 50 ml of n-octane were charged into an autoclave with an internal volume of 200 ml, and after introducing ammonia in the same manner as in Example 6, the autoclave was maintained at 74° C. and a pressure of 33 Kg/cm ² G for 3 hours with stirring. 11 mol% of the 1,4-dibromobenzene was changed, and 4-bromoaniline was obtained in a yield of 11 mol% based on the 1,4-dibromobenzene charged.

Claims (1)

[Claims] 1. A method for aminating 1,4-dibromobenzene in a liquid phase using ammonia, in which at least one selected from copper and copper compounds is catalyzed under substantially anhydrous conditions. 1,4-dibromobenzene is aminated at a temperature of 30°C or higher and lower than the critical temperature of ammonia.
Method for aminating dibromobenzene. 2 In a method for aminating 1,4-dibromobenzene in a liquid phase using ammonia, 1,4-dibromobenzene is
- Under substantially anhydrous conditions in the coexistence of an inert organic solvent that does not substantially dissolve diaminobenzene,
Amino of 1,4-dibromobenzene, characterized in that 1,4-dibromobenzene is aminated at a temperature of 30°C or higher and lower than the critical temperature of ammonia using at least one selected from copper and copper compounds as a catalyst. method.