JPH05208940A - Production of alpha-@(3754/24)3-aminophenyl)ethylamine - Google Patents

Abstract

PURPOSE:To obtain high-purity alpha-(3-aminophenyl)ethylamine in high yield. CONSTITUTION:The two-stage reaction for passing m-nitroacetophenone of formula I through m-aminoacetophenone of formula II and providing alpha-(3- aminophenyl)ethylamine of formula III is carried out in the presence of two kinds of a palladium catalyst and a nickel catalyst mixed in the same solvent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing α- (3-aminophenyl) ethylamine. This compound is expected to have a characteristic performance as a curing agent for epoxy resin, a curing agent for polyurethane resin or a polyurea resin. Further, by phosgenating this, a diisocyanate in which an amino group is converted into an isocyanate can be provided. Moreover, the two amino groups of this α- (3-aminophenyl) ethylamine are different because they are attached directly to the benzene ring and the other is attached to the secondary carbon in the form hindered by the methyl group. It is expected that this compound and the diisocyanates derived therefrom will have characteristic properties.

[0002]

2. Description of the Related Art As a method for producing α- (3-aminophenyl) ethylamine, m-nitroacetophenone is used as a starting material to carry out a catalytic hydrogenation reaction in the presence of a catalyst and ammonia to give diamino in one step. There is a method for performing the conversion (JP-A-2-145548). This method is advantageous in that it is a one-step reaction, but in addition to using a large amount of ammonia and a catalyst, α- (3-aminophenyl) ethyl alcohol represented by the formula (IV) It had the drawback of producing many by-products.

[0003]

[Chemical 4]

The present inventors carried out catalytic hydrogenation reaction using m-nitroacetophenone as a starting material in the presence of a noble metal catalyst such as palladium, rhodium or platinum to obtain m-aminoacetophenone, and then removing these from the reaction solution. The catalyst is removed, and a reductive amination reaction is carried out in the presence of a catalyst such as Raney nickel, Raney cobalt, nickel-diatomaceous earth, an alcoholation inhibitor such as a weak acid or an ammonium salt of a weak acid, and ammonia to obtain α- (3- Previously, a method for producing aminophenyl) ethylamine was proposed (Japanese Patent Laid-Open No. 3-30083).
No. 93749). In this method, although the by-product of α- (3-aminophenyl) ethyl alcohol is suppressed, it is still necessary to replace the catalyst when the catalytic hydrogenation reaction shifts to the reductive amination reaction. However, there is a drawback that complicated unit operations such as nitrogen substitution and hydrogen substitution are required.

[0005]

An object of the present invention is to eliminate the catalyst filtration step and the accompanying complicated unit operations such as nitrogen substitution and hydrogen substitution, and to obtain a high-purity α-
It is to provide a production method for obtaining (3-aminophenyl) ethylamine.

[0006]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have conducted a two-step reaction via m-aminoacetophenone in the same solvent to produce two kinds of catalysts. When the reaction is carried out in the presence of mixed catalysts, not only the catalyst filtration step can be omitted, but also the synergistic effect of the two kinds of catalysts can reduce the amount of the catalyst used, and the α- (3 It was found that -aminophenyl) ethylamine can be produced, and the present invention has been completed. That is, the present invention provides m-nitroacetophenone represented by the formula (II)

[0007]

[Chemical 5] Is subjected to catalytic hydrogenation reaction in an organic solvent in the presence of a palladium catalyst and a nickel catalyst, and m-aminoacetophenone represented by the formula (III)

[0008]

[Chemical 6] After that, and subsequently, a reductive amination reaction is carried out in the presence of ammonia.
-(3-aminophenyl) ethylamine

[0009]

[Chemical 7] The present invention relates to a manufacturing method of.

The reaction of the present invention is carried out by the following reaction formula (V),
It is represented by (VI) (Chemical Formula 8).

[0011]

[Chemical 8] That is, it is a method of first producing m-aminoacetophenone and then producing α- (3-aminophenyl) ethylamine.

According to the method of the present invention, α- (3-aminophenyl) ethylamine is subjected to catalytic hydrogenation reaction represented by the reaction formula (V) using the same catalyst, and then ammonia is injected. Then, it can be obtained by performing the reductive amination reaction represented by the reaction formula (VI). Reaction formula (V)
In the catalytic hydrogenation reaction represented by, after dissolving m-nitroacetophenone in an organic solvent, hydrogen is introduced under pressure or blown with hydrogen in the presence of a catalyst.
The temperature of this reaction is in the range of 10 ° C to 100 ° C, preferably 20 ° C to 60 ° C. Hydrogen pressure is 0 Kg / cm ² G ~ 20
In the range of Kg / cm ² G, preferably, 1Kg / cm ² G~10Kg
/ cm ² G is preferred. In the reductive amination reaction represented by the reaction formula (VI), after injecting ammonia into the reaction solution obtained by the formula (V), hydrogen is injected under pressure or hydrogen is blown into the reaction solution for reaction. The temperature of this reaction is 80 ℃ ~ 150 ℃,
Desirably, it is 90 ° C to 120 ° C. Hydrogen pressure is 10 Kg / cm ²
G~100 Kg / cm ² G, ^{preferably, 20Kg / cm 2 G~50Kg / cm} 2
G. The amount of ammonia used is 1.0 to 10 equivalents relative to m-nitroacetophenone. The target α- (3
In order to keep the yield of -aminophenyl) ethylamine high, it is desirable to thoroughly stir after injecting ammonia.

The catalyst used in the present invention is a mixed catalyst of a palladium catalyst and a nickel catalyst. Palladium catalyst can be used in a metal state, but usually,
It is used by adhering it to the surface of a carrier such as carbon, barium sulfate, silica gel or alumina. Industrially, it is desirable to use a palladium carbon catalyst. The amount used is, for example, commercially available 5% palladium carbon (50% wet
Product), the raw material m-nitroacetophenone 1
It is preferably 0.01 part to 2 parts with respect to 00 parts, and more preferably 0.15 part to 0.5 part. As the nickel catalyst, Raney nickel, nickel-diatomaceous earth, stabilized nickel and the like can be used, but it is particularly preferable to use a stabilized nickel catalyst. The amount used is, for example, m-when using commercially available stabilized nickel (Ni content 50%).
It is preferably 1 part to 20 parts, and more preferably 2 parts to 10 parts, relative to 100 parts of nitroacetophenone.

The organic solvent used in the present invention may be any solvent that is usually used in a catalytic hydrogenation reaction, but lower alcohols such as methanol and ethanol having a high solubility of ammonia are advantageous. The amount of the solvent used is not particularly limited, but 1 to 15 times the weight of the raw material is usually sufficient. After completion of the reaction, the catalyst was removed by filtration and then distilled under reduced pressure to obtain a highly pure α-
(3-Aminophenyl) ethylamine is obtained. In the method of the present invention, the intermediate m-aminoacetophenone, which is a useful compound similar to α- (3-aminophenyl) ethylamine, can be taken out as a product. In that case, when the reaction represented by the reaction formula (V) is completed, the reaction solution is taken out and subjected to post-treatment such as solvent removal and purification.

[0015]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. Example 1 In a SUS316 autoclave with an agitator having an internal volume of 500 ml,
33.0 g (0.2 mol) of m-nitroacetophenone, 66 g of methanol as a solvent, 5% palladium carbon catalyst (5
0% Wet product) 0.20 g, stabilized nickel (Ni content 50%
(Product) 2.70 g was charged and replaced with nitrogen. Then, in order to replace nitrogen with hydrogen, hydrogen was injected up to 10 kg / cm ² G.
It was connected to a 3000 ml hydrogen holder, and hydrogen was injected under pressure. Absorption of hydrogen occurs when stirring is started. After about 2 hours, the absorption of hydrogen stopped, so the stirring was stopped. The pressure was in the range of 10 kg / cm ² G to 2 kg / cm ² G. As a result of analyzing a part of the reaction solution by liquid chromatography, m
The yield of -aminoacetophenone was 99.3%. Then, after introducing about 12 g of liquid ammonia, the temperature was raised to 95
The mixture was stirred at 0 ° C for 2 hours. As was pressed hydrogen 50 kg / cm ² G, subjected to reductive amination reaction in the range of internal pressure 50~30kg / cm ² G, the absorption of hydrogen ceased at a lapse of about 5.5 hours, the stirring was stopped. After cooling to room temperature, the reaction solution was taken out and the catalyst was filtered off. The filtrate was distilled under reduced pressure to remove ammonia and solvent, and then vacuum distilled at a pressure of 5 to 6 mmHg to obtain 25.1 g of a fraction having a distillation temperature of 120 to 122 ° C.
(Total yield from m-nitroacetophenone 92.1%)

Example 2 An SUS316 autoclave equipped with a stirrer having an internal volume of 500 ml was used.
33.0 g (0.2 mol) of m-nitroacetophenone, 66 g of methanol as a solvent, 5% palladium carbon catalyst (5
0% Wet product) 0.05 g, Stabilized nickel (Ni content 50%
Product) 0.675 g was charged and replaced with nitrogen. Next, in order to replace the nitrogen with hydrogen, the hydrogen was connected to a 3000 ml hydrogen holder in which hydrogen was injected up to 10 kg / cm ² G, and hydrogen was injected under pressure. Absorption of hydrogen occurs when stirring is started. After about 3 hours, the absorption of hydrogen stopped, so the stirring was stopped.
The pressure was in the range of 10 kg / cm ² G to ² kg / cm ² G. When a part of the reaction solution is analyzed by liquid chromatography, m-
The yield of aminoacetophenone was 99.4%. Next, after introducing about 12 g of liquid ammonia, raise the temperature to 95 ° C.
It was stirred for 2 hours. As was pressed hydrogen 50 kg / cm ² G, subjected to reductive amination reaction in the range of internal pressure 50~30kg / cm ² G, the absorption of hydrogen ceased at a lapse of about 8 hours, stirring was stopped. After cooling to room temperature, the reaction solution was taken out and the catalyst was filtered off. The filtrate was distilled under reduced pressure to remove ammonia and solvent, and then vacuum distilled at a pressure of 5 to 6 mmHg to obtain 26.7 g of a fraction having a distillation temperature of 120 to 122 ° C.
(Total yield from m-nitroacetophenone 97.3%)

[0017]

According to the production method of the present invention, a two-step reaction from m-nitroacetophenone via m-aminoacetophenone is carried out in the same solvent in the presence of two kinds of catalysts, a palladium catalyst and a nickel catalyst. As a result, after the completion of the reaction in the first step, not only the catalyst filtration step can be omitted, but also a highly pure target product can be produced in a high yield. Therefore, α- (3-aminophenyl) ethylamine is extremely simple and advantageous. Is a manufacturing method.

Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical display location C07C 225/22 7457-4H // C07B 61/00 300 (72) Inventor Ryuji Haseyama Kasama Town, Sakae Ward, Yokohama City, Kanagawa Prefecture 1190 Mitsui Toatsu Chemicals, Inc.

Claims (1)

[Claims] 1. α- (3-represented by formula (I)
Aminophenyl) ethylamine embedded image In the production of m-nitroacetophenone represented by the formula (II) Is subjected to catalytic hydrogenation reaction in an organic solvent in the presence of a palladium catalyst and a nickel catalyst mixed together to give m-aminoacetophenone represented by the formula (III) And then the reductive amination reaction is carried out in the presence of ammonia. A method for producing α- (3-aminophenyl) ethylamine.