JPS62195350A - Production of n-alkyl aromatic amine - Google Patents

Abstract

PURPOSE:In reacting an aromatic primary amine with an alkylating agent, to obtain the titled substance useful as an intermediate for a coupler for color photography, etc., industrially advantageously, by using a specific crystalline metallic silicate as a catalyst. CONSTITUTION:An aromatic primary amine is reacted with an alkylating agent by the use of a crystalline metallic silicate having a molar ratio (SiO2/M2O3) of silicon dioxide (SiO2) and a trivalent metallic oxide (M2O3; M is trivalent metal) of >=12, preferably 40-3,000 as a catalyst at 150-450 deg.C, preferably 200-400 deg.C, preferably at normal pressure -5kg/cm<2>G to give the aimed com pound. The crystalline metallic silicate having the molar ratio of SiO2/Mn2O3 is sufficient, other conditions are not particularly limited and a metallic silicate having a main cavity of oxygen 10-membered ring, especially a metallic silicate belonging to metallic silicate of pentacle type is preferable.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for producing N-alkyl aromatic amines (N-monoalkyl aromatic amines), and more specifically, the present invention relates to a method for producing N-alkyl aromatic amines (N-monoalkyl aromatic amines). Possibly N, N
- A method for suppressing the by-product of dialkyl aromatic amines and efficiently producing target N-alkyl aromatic amines with high selectivity.

[Problems to be solved by conventional technology and invention]N
-Alkyl aromatic amines are compounds useful as intermediates in the production of color formers for color photography, pharmaceuticals, agricultural chemicals, dyes, and the like. Various methods are known for producing this N-alkyl aromatic amine. Furthermore, various solid acid catalysts are used for the reaction between the aromatic primary amine and the fullkylating agent, and it has been reported that the catalytic activity is particularly high when aluminum is used. However, with this alumina catalyst, when methanol is used as an alkylating agent, more N,N-dimethylaromatic amine is produced than the target N-methylaromatic amine, and when ethanol is used, N-ethyl It has been reported that although the amount of aromatic amines produced increases, the amount of nuclear alkylated by-products also increases7/(r
nd, Eng, chem,.

Arc, 1579-1584 (1951)). As one solution to these problems, a method has been proposed in which a reaction is carried out using a silica-alumina catalyst containing a silica component in the range of 1 to 10% by weight (Japanese Patent Publication No. 60-4850).
Publication No. 1). However, this method cannot sufficiently suppress the production of by-products, and there is still room for further improvement.

An object of the present invention is to provide a method for producing N-alkyl aromatic amines in which the by-product of N,N-dialkyl aromatic amines is further suppressed compared to the above-mentioned methods.

[Means for solving problems]

That is, the present invention combines an aromatic primary amine and an alkylating agent with silicon dioxide (SiO2) and a trivalent metal oxide (MzO2).
z; M represents a trivalent metal. ) and the molar ratio (S ich/
The present invention provides a method for producing an N-alkyl aromatic amine, characterized in that the reaction is carried out in the presence of a catalyst consisting of a crystalline metal silicate having 12 or more M2O3).

The raw material compound used in the method of the present invention may be any aromatic primary amine, and various compounds may be mentioned, but usually aniline, 0-toluidine, m-toluidine, p-toluidine, 0-ethylaniline, m- Ethylaniline, p
-ethylaniline, 07nisidine, m-anisidine,
Examples include p-anisidine, 0-chloroaniline, m-chloroaniline, p-chloroaniline, and particularly preferred are aniline, toluidine, and the like.

In addition, the alkylating agent is a primary alcohol.

There are various types such as ethers derived from primary alcohols and halogenated alkyl olefins, and especially primary alcohols.
Alcohols, ethers derived from primary alcohols, and the like are preferred. Specifically, methanol, ethanol, n-
propatool, n-butyl alcohol, diethyl ether, dimethyl ether, methyl-t-butyl ether,
Isoamyl alcohol. Benzyl alcohol etc. cause irritation. Also, the amount of alkylating agent used depends on the reaction conditions.

Although it may be determined as appropriate depending on the type of the desired reaction product, the ratio with the aromatic primary amine, which is the raw material compound, is usually set to the ratio of aromatic primary amine/alkylating agent = 10/1 to 1/1.
20 (molar ratio), preferably 5/1 to 115 (molar ratio).

The crystalline metal silicate used as a catalyst in the method of the present invention has a crystal skeleton mainly composed of silicon dioxide (SiO /MzO
3 (Mo/L/ratio) is 12 or more, preferably 40 to 300
0. Here, if the Sing/MzCh (molar ratio) is less than 12, the selectivity is low and the activity is significantly reduced, which is not preferable.

The crystalline metal silicate in the method of the present invention may have the above-mentioned S iOz / Mz 03 (molar ratio), and other conditions are not particularly limited.
Crystalline metal silicates belonging to the metal silicates having a pentasil type structure are preferred, and the trivalent metals (M) constituting the crystalline metal silicates include aluminum (AI), gallium(
Ga), boron (B).

Iron (Fe), Indium (In), Lanthanum (La)
.

Examples include scandium (S c ), yttrium (Y), chromium (Cr), and titanium (Ti), and examples include one or more metal elements among these.

Specific examples of the above-mentioned crystalline metal silicates include:
ZSM-5 described in publications such as U.S. Pat. There is ZSM-11. In addition, ZS described in Japanese Patent Application Laid-open No. 52-139029, etc.
Crystalline aluminosilicates such as ZSM-21, which is described in publications such as M-35 and US Pat. No. 4,001,346, and which have a ratio of 5iOz/MzO+ of 12 or more can also be used.

Furthermore, as an example where M is B, the ZSM described in JP-A-53-55500 or JP-A-55-7598
There are crystalline borosilicates having a -5 type structure or a ZSM-11 type structure. As an example where M is Fe, the Journal of Ca
35, pp. 256-272 (197
4), JP-A No. 127898 or JP-A No. 5
Examples where 0M is Ga include crystalline iron silicates such as ferrierite described in No. 5-85415, etc.; There are silicates.

M is In, La, Sc, Y, Cr+ TLBe, M
For example, the cation of AI incorporated into the skeleton in the crystalline aluminosilicate is In,
La, Sc, Y, Cr+ Tit Be
.

There are crystalline metal silicates having a structure in which Mn is replaced by cations.

Among these, M, which is a trivalent metal, is AI and Ga.

Particularly preferred is B.

The crystalline metal silicate used in the method of the present invention can be prepared by a known method.

For example, a method for synthesizing a pentasil-type crystalline metal silicate represented by the above-mentioned ZSM-5S E5ite is to synthesize silica in the presence or absence of a C2 to CS tetraalkylammonium halide or other amines. silicic acid or its condensates, such as colloidal silica or water glass, or silicates, metal oxides (MzOs) as sources, e.g. aluminum sulfate, gallium nitrate, boric acid, ferric sulfate, sulfuric acid. It is known that it can be prepared by hydrothermal synthesis using a mixture whose main components are salts such as sulfates, nitrates, or oxyacids of metal elements M such as chromium and sodium aluminate.

Also known is a method in which an alkali metal hydroxide such as sodium or an alkali metal compound such as a halide is allowed to coexist during the hydrothermal synthesis.

The crystalline metal silicates obtained by these methods are generally not of the H9 type, but have quaternary ammonium ions and/or alkali metal ions such as Na+ substituted for H9, so it is difficult to convert them to the H' type. is preferred. This exchange can be easily accomplished by known methods.

For example, it is known that converting quaternary ammonium ions to H″″ can be achieved by firing at a temperature of approximately 500 to 600°C, while replacing alkali metal ions such as Na″ with H″ For example, an alkali metal salt type crystalline metal silicate is treated with an aqueous solution of an ammonium salt such as ammonium nitrate or ammonium chloride to obtain an ammonium salt type crystalline metal silicate, and then calcined in air at 300 to 600°C. death,
A method of obtaining H° type crystalline metal silicates is often used.

In addition to these methods, a method of directly treating with dilute acid such as dilute hydrochloric acid can also be used.

Various methods other than these are known as methods for synthesizing crystalline metal silicates.

The crystalline metal silicate used as a catalyst in the method of the invention can be synthesized by any of these methods, and the invention is not limited to the use of a catalyst by a particular method of preparation.

In the present invention, the crystalline metal silicate is preferably in the H type, but as long as the purpose of the present invention is not hindered, some or all of the H in the catalyst may contain other cations, such as magnesium. ions, calcium ions, lanthanum ions, etc. may be substituted.

The solid catalyst in the present invention can be in any shape such as powder, granules, strips, spheres, and pellets.

In the present invention, when hydrothermally synthesizing crystalline metal silicate by blending organic compounds such as quaternary amines,
In order to improve the catalytic activity, it is preferable to calcinate the crystalline silicate in an inert gas stream such as air and/or nitrogen before the reaction.

In this case, the firing conditions are Il of the crystalline metal silicate.
1, at a temperature of 400 to 600°C, preferably 450 to 550°C, for 1 hour or more, preferably 3
Organic compounds in the metal silicate are removed by heating for a period of time or longer.

In the method of the present invention, the target N-alkyl aromatic amine (in detail (N-monoalkyl aromatic amine) can be obtained efficiently, and the by-product of N,N-dialkyl aromatic amine can be suppressed.

The reaction of the aromatic amine proceeds by contacting the aromatic primary amine and the alkylating agent with the above-mentioned crystalline metal silicate catalyst, and is not reconstituted.

However, the reaction temperature is usually selected within the range of 150 to 450°C, preferably 200 to 400°C.

In addition, the reaction method may be either a batch method or a flow method.
In the case of a batch method, the reaction time should be 10 minutes to 24 hours, preferably 30 minutes to 8 hours, and in the case of a flow method, the reaction time should be 3 hours.
V (weight hourly space velocity) should be between 0.1 and 100 hr-', preferably between 1 and 10 hr-'.

Although this reaction proceeds satisfactorily without the use of a solvent, a suitable solvent may be used if desired.

In either case, the reaction can be carried out under autogenous pressure or under increased pressure at the reaction temperature. Specifically, normal pressure ~2
0kg/cm"G, preferably normal pressure to 5kg/cm"G
A range of is appropriate.

The amount of crystalline metal silicate used as a catalyst in the method of the present invention may be determined using the above-mentioned WH3V in the case of a flow method, but in the case of a batch method, the type of catalyst 9 It depends on the type of amine, the type of alkylating agent, and other conditions, but usually the aromatic primary
0.1-20% by weight relative to the amine, preferably 1-1
A range of 0% by weight is sufficient.

After the reaction is complete, the catalyst is separated and removed using a solid-liquid separation operation, and then
N-alkyl aromatic amines may be isolated and purified by distillation, etc., but in the case of a batch system, normally the produced N-alkyl aromatic amines can be taken out of the system by distillation without separating and removing the catalyst. The unreacted aromatic primary amine recovered by this distillation operation can be reused as a starting material.

The crystalline metal silicate used as a catalyst in the method of the present invention can be used repeatedly as a highly active catalyst by appropriately performing a calcination operation for regeneration.

〔Effect of the invention〕

As described above, according to the method of the present invention, the by-product of N,N-dialkyl aromatic amines is suppressed, so that target N-methylaniline, N-ethylaniline, N-ethyltoluidine, etc. Alkyl aromatic amines can be produced with high selectivity and good yield. Further, in the method of the present invention, the crystalline metal silicate used has excellent thermal stability,
Since it can be used at relatively high temperatures, the reaction rate can be maintained sufficiently high, the activity can be maintained for a long time, and it can be effectively used as a catalyst any number of times by performing regeneration treatment. Therefore, the production cost is lower than that of conventional methods, making it an extremely advantageous method industrially.

Further, the N-alkyl aromatic amine obtained by the method of the present invention can be effectively used as a color former for color photography, an intermediate for chemicals such as pharmaceuticals, agricultural chemicals, and dyes.

〔Example〕

Next, the present invention will be explained in more detail based on examples.

Reference Example 1 (Preparation of crystalline aluminosilicate) 7.5 g of aluminum sulfate was dissolved in 250 ai of water, and further 17.6 g of concentrated sulfuric acid and 26.3 g of tetra-n-propylammonium bromide were dissolved therein.
Dissolve 211.0 g of water glass [J Sodium Silicate No. 3: manufactured by Nihon Kagaku Kogyo ■] in 250 ai of water to obtain B solution, further dissolve 79.0 g of sodium chloride in 122 ai of water, and place the liquid in an autoclave. and heat at 170℃ for 20 minutes.
Heat treated for hours. After cooling, the contents were filtered and washed with water.
It was dried at 0°C for 12 hours. X-ray diffraction analysis of the product confirmed that it was ZSM-5. Obtained Z
56.5g of sodium type ZSM-5 was obtained by baking SM-5 at 550°C for 6 hours. This sodium type ZSM-5 was added to a 1N aqueous ammonium nitrate solution weighing 5 times its weight, and the mixture was refluxed for 8 hours. Thereafter, the mixture was cooled and allowed to stand, and the supernatant was removed by decantation. Furthermore, reflux/
After repeating the decantation operation three times, the contents were filtered, washed with water, and dried at 120°C for 12 hours to obtain ammonium type ZSM-5. This thing's Stow/Ah0
3=90 (molar ratio). This ammonium type Z
SM-5 was fired in air at 550°C for 4 hours to form H-type ZSM.
-5, that is, a crystalline aluminosilicate was obtained.

Reference Example 2 (Preparation of crystalline gallosilicate) 2.34 g of gallium nitrate, 4.42 g of concentrated sulfuric acid, and 6.58 g of tetra-n-propylammonium bromide were added to 62 ml of water.
Solution A in which 52.78 g of water glass [J Sodium Silicate No. 3; manufactured by Nihon Kagaku Kogyo ■] was dissolved in 62 L of water and 19.75 g of sodium chloride were dissolved in 3
A solution ct was prepared by dissolving it in 0mlt. Solutions A and B were then added dropwise to solution C at the same time. The resulting mixture was placed in an autoclave and heated at 24°C at tt'roC.
Allowed time to react. After cooling, the contents of the autoclave were filtered, washed with water, dried at 120°C for 12 hours, and further heated at 600°C.
Sodium type crystalline gallosilicate 9 was baked for 6 hours at
．． 6g was obtained.

Next, the obtained gallosilicate was added to 5 times the weight of 1N ammonium nitrate solution, heated at 80° C. for 8 hours, cooled, and filtered. Furthermore, the solid matter is heated and filtered 3 times.
After repeating the process several times, it was washed with water and dried at 120°C for 16 hours to form the ammonium type crystalline gallosilicate Sing and Gat.
The composition ratio of oz is 5iOz/Ga! 03=75.5 (molar ratio).

Furthermore, this gallosilicate was determined by X-ray diffraction into ZSM-
5 structure. This ammonium type crystalline gallosilicate was calcined in air at 550°C for 4 hours to obtain H type crystalline gallosilicate.

Reference Example 3 (Preparation of crystalline borosilicate) Boron oxide 1.
Dissolve 34 g in 250 ai of water, and add 17.6 g of concentrated sulfuric acid and 26.3 g of tetra-n-propylammonium bromide. Let this be liquid A.
Water glass [J Sodium Silicate No. 3: Manufactured by Nihon Kagaku Kogyo ■) 2
11. Og was dissolved in 250 l of water to obtain liquid B, and 79.0 g of sodium chloride was further dissolved in 122 ai of water to form liquid C.

Next, the above-mentioned solutions A and B were simultaneously added dropwise to solution C at room temperature for 10 minutes. The resulting mixed solution was placed in an autoclave and heat-treated at 170°C for 20 hours. After cooling, the contents were filtered, washed with water, and dried at 120°C for 12 hours.
The mixture was further calcined at 550° C. for 6 hours to obtain 45.3 g of sodium type crystalline borosilicate.

Next, the obtained borosilicate was added to 5 times the weight of a 1N ammonium nitrate aqueous solution, and the mixture was refluxed for 8 hours. after that,
The mixture was cooled and allowed to stand, and the supernatant was removed by decantation. After repeating the reflux and decantation operations three times, the contents were filtered, washed with water, and dried at 120°C for 12 hours to obtain ammonium-type borosilicate. Stow/BzOs of this product was 100 (molar ratio). This ammonium type borosilicate was dissolved in air at 550%
C. for 4 hours to obtain H-type crystalline borosilicate.

Example 1 2 g of the crystalline aluminosilicate obtained in Reference Example 1 was charged into an atmospheric pressure fixed bed flow reaction tube, and while maintaining the reaction temperature at 250°C, the feeding ratio of aniline and methanol was adjusted to aniline/methanol. W H so that it becomes 1/2 (molar ratio)
The N-alkylation reaction was carried out by supplying the solution under the conditions of SV 2.5 hr-'. Table 1 shows the results one hour after the start of the reaction.

Example 2 The same operation as in Example 1 was performed except that the reaction temperature was 200°C. The results are shown in Table 1.

Example 3 The same operation as in Example 1 was performed except that ethanol was used instead of methanol and the reaction temperature was 300°C. The results are shown in Table 1.

Example 4 In Example 3, WH3V was set to 10. The same operation as in Example 3 was performed except that the temperature was changed to "Ohr".

The results are shown in Table 1.

Example 5 The same operation as in Example 3 was performed except that p-)luidine was used in place of aniline. The results are shown in Table 1.

Example 6 In Example 3, diethyl ether was used instead of ethanol, and the feeding ratio was changed to aniline/diethyl ether=
The same operation as in Example 3 was performed except that the molar ratio was 1/1. The results are shown in Table 1.

Example 7 In Example 3, the same operation as in Example 1 was performed except that the crystalline gallosilicate obtained in Reference Example 2 was used instead of the crystalline aluminosilicate. The results are shown in Table 1.

Example 8 In Example 3, the same operation as in Example 1 was performed except that the crystalline borosilicate obtained in Reference Example 3 was used instead of the crystalline aluminosilicate. The results are shown in Table 1.

Comparative Example 1 The same operation as in Example 1 was performed except that activated alumina (manufactured by Sumitomo Chemical Co., Ltd., trade name NKH-3) was used instead of crystalline aluminosilicate.

The results are shown in Table 1.

Comparative Example 2 The same operation as in Example 3 was performed except that activated alumina (manufactured by Sumitomo Chemical Co., Ltd., trade name NKH-3) was used instead of crystalline aluminosilicate.

The results are shown in Table 1.

Claims (5)

[Claims] (1) Aromatic primary amine and alkylating agent are combined with silicon dioxide (SiO_2) and trivalent metal oxide (M_2O_3;
M represents a trivalent metal. ) and molar ratio (SiO_2/M_
2O_3) is reacted in the presence of a catalyst consisting of a crystalline metal silicate of 12 or more. (2) The manufacturing method according to claim 1, wherein the aromatic primary amine is aniline or toluidine. (3) Claim 1, wherein the alkylating agent is a primary alcohol or an ether derived from a primary alcohol.
Manufacturing method described in section. (4) The manufacturing method according to claim 1, wherein the crystalline metal silicate is a zeolite having a main cavity of a 10-membered oxygen ring. (5) The trivalent metal constituting the crystalline metal silicate is one or more metals selected from the group consisting of aluminum, gallium, boron, iron, indium, lanthanum, scandium, yttrium, chromium, and titanium. A manufacturing method according to claim 1.