JPH02138229A - Production of alkyl-substituted aromatic hydrocarbon - Google Patents

Abstract

PURPOSE:To obtain the subject substance useful as an intermediate raw material for fine chemicals in high yield and efficiency by reacting an olefin with an aromatic hydrocarbon having H on the alpha-site of a side chain in the presence of a solid base prepared from alumina, an alkali metal hydroxide and an alkali metal at a specific temperature. CONSTITUTION:The objective compound is produced by alkylating (A) an aromatic hydrocarbon having H on the alpha-site of a side chain (e.g., toluene) with (B) an olefin usually at 0-300 deg.C under a reaction pressure of usually from atmospheric pressure to 200kg/cm<2> in the presence of (C) a catalyst consisting of a solid base produced by heating alumina, an alkali metal hydroxide and an alkali metal in an inert gas atmosphere at 200-600 deg.C (preferably reacting alumina with alkali metal hydroxide at 250-550 deg.C, especially 260-480 deg.C and reacting the reaction product with alkali metal at 300-450 deg.C). The amounts of the alkali metal and alkali metal hydroxide in the catalyst are 2-15wt.% and 5-40wt.% based on the alumina, respectively.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a method for producing an alkyl-substituted aromatic hydrocarbon, and more particularly, to a method for producing an alkyl-substituted aromatic hydrocarbon, in particular a solid base prepared from alumina, an alkali metal hydroxide, and an alkali metal at a specific temperature. The present invention relates to a method for producing an alkyl-substituted aromatic hydrocarbon by reacting an aromatic hydrocarbon having a hydrogen atom at the α-position of the side chain with an olefin in the presence of the present invention to alkylate the α-position.

<Prior art> Alkyl-substituted aromatic hydrocarbons are useful as intermediate raw materials for fine chemicals such as agricultural products, pharmaceuticals, and chemical products, and in the presence of a base catalyst, aromatic hydrocarbons having hydrogen at the α-position of the side chain and olefins are combined. Obtained by reacting.

For example, a method using a catalyst consisting of metallic sodium and chlorotoluene as a catalyst, a method using a catalyst in which metallic sodium is supported on potassium carbonate, etc. are known (J,
Am, Chem, Soc, 78.4316 (1956
), British Patent No. 1269280, JP-A-61-532
Publication No. 29).

<Problems to be Solved by the Invention> However, when the above-mentioned catalyst is used, there are problems such as insufficient catalytic activity and a low yield of alkyl-substituted aromatic hydrocarbons per catalyst, and problems between the catalyst and the product. There are problems in that the separation of catalysts is complicated, and furthermore, when the catalyst comes into contact with air or moisture in the atmosphere, it is easily deactivated and there is a risk of ignition.

Ku! Means for Solving Problem I> The present inventors have conducted intensive studies on alkylation catalysts in order to develop an excellent method for producing alkyl-substituted aromatic hydrocarbons by alkylating the α-position of aromatic hydrocarbons. result,
A specific solid base obtained by heat treating alumina, an alkali metal hydroxide, and an alkali metal exhibits extremely high alkylation activity and efficiently produces the desired alkyl-substituted aromatic hydrocarbon with a small amount of catalyst. Moreover, it is easy to separate from reaction products, and the solid base has little risk of ignition even when it comes into contact with air or moisture in the atmosphere.
In addition to discovering that it is extremely easy to handle, the present invention was completed after further various studies.

That is, the present invention uses alumina, an alkali metal hydroxide, and an alkali metal as a catalyst when alkylating an aromatic hydrocarbon having a hydrogen atom at the α-position of the side chain with an olefin to produce an alkyl-substituted aromatic hydrocarbon. The present invention provides an industrially excellent method for producing alkyl-substituted aromatic hydrocarbons, which is characterized by using a solid base obtained by heat treatment at a temperature of 200 to 600'C in an inert gas atmosphere.

The present invention is characterized by using alumina, an alkali metal hydroxide, and a solid base obtained by heat-treating an alkali metal at a specific temperature, but the alumina may be in various forms other than α-alumina. can be used, for example T-
Examples include 1χ-1ρ-alumina. Alumina preferably has a large surface area. Also, examples of alkali metals include lithium, sodium, and potassium in Group 1 of the periodic table.
An alkali metal such as rubidium is used, preferably sodium, potassium or a mixture thereof, more preferably potassium. The amount of alkali metal used is usually 2 to 15 wt% based on alumina.

Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, etc., but sodium hydroxide, potassium hydroxide, and cesium hydroxide are preferably used. . Two or more types of alkali metal hydroxides can also be used. The amount used is usually 5 to 40wt for alumina.
%.

In preparing the solid base, it is preferable to first treat alumina with an alkali metal hydroxide and then with an alkali metal under an inert gas atmosphere.

For example, a method of adding an alkali metal hydroxide to alumina and subjecting it to a heating action, then adding an alkali metal to this and subjecting it to a heating action, or impregnating alumina with a solution of an alkali metal hydroxide, drying it, subjecting it to a heating action, and then Examples include a method in which an alkali metal is added to this to cause a heating effect.

Examples of the inert gas include nitrogen, helium, and argon.

The catalyst preparation temperature is important, usually 200 to 600'C.
.

Preferably, the temperature at which alumina and alkali metal hydroxide are allowed to react is 250 to 550°C, more preferably 26°C.
The temperature range is 0 to 480°C, and the temperature at which the alkali metal is applied is 200 to 450°C.

The heating time depends on the selected temperature conditions, etc., but usually 0.5 to 10 hours is sufficient for the step of applying an alkali metal hydroxide, and usually 10 to 300 minutes for the step of applying an alkali metal.

In this way, a solid base is obtained which is highly active, has good fluidity and operability, and has no risk of ignition even when exposed to air.

The present invention uses such a solid base to react an aromatic hydrocarbon having hydrogen at the α-position of its side chain with an olefin. , a fused polycyclic aromatic hydrocarbon is used. The side chains may be combined to form a ring.

For example, toluene, ethylbenzene, isobutylbenzene, n-propyrhenzene, n-butylbenzene, 5ec
Examples include -butylbenzene, isobutylbenzene, xylene, cymene, diisopropylbenzene, methylnaphthalene, tetrahydronaphthalene, and indane. Toluene, ethylbenzene and isopropylbenzene are preferably used.

Further, as the olefin, an olefin having 2 to 20 carbon atoms is usually used, and either a linear or branched olefin may be used. Further, it can be used regardless of whether the double bond is located at the terminal or internally. Terminal olefins are preferably used.

Specific examples of these compounds include ethylene, propylene, ■-butene, 2-butene, isobutylene, l-pentene, 2-pentene, 1-hexene, 2=hexene,
3-hexene, 1-heptene, 2-heptene, 3-heptene, octene, nonene, 3-methyl-1-butene, 2
-Methyl-2-butene, 3-methyl-1-pentene, 3
-Methyl-2pentene and the like.

Ethylene, propylene, l-butene, 2-butene are preferably used.

In carrying out the alkylation reaction, batch method,
Both distribution systems using fluidized beds and fixed beds can be adopted.

The reaction temperature is usually 0 to 300°C, preferably 20 to 20°C.
00″C, and the reaction pressure is usually atmospheric pressure to 200Kg.
/c+1, preferably 2 to 100 Kg/cm".

The molar ratio of olefin to aromatic hydrocarbon is usually 0.1 to IO1, preferably 0.2 to 5.

The amount of catalyst used in the batch method is usually 0.1 to 20 wtx of the aromatic hydrocarbon used, preferably 0.2
The reaction time is usually 0.5 to 50 hours.
Preferably it is 1 to 25 hours. The total feed rate of aromatic hydrocarbons and aliphatic olefins in the flow reaction is usually 0.1 to 600 hr-', preferably 0.5 to 400 hr' at LH3V.

<Effect of the invention> In this way, alkyl-substituted aromatic hydrocarbons are produced,
According to the present invention, target alkyl-substituted aromatic hydrocarbons can be produced extremely efficiently with a small amount of catalyst and even under mild conditions.

In addition, the method of the present invention is advantageous in this respect as not only the handling of the catalyst but also the post-treatment after the reaction is extremely easy.

<Example> The present invention will be explained in more detail with reference to Examples below.
The present invention is not limited only to these examples.

Catalyst Preparation Example (Solid Base A) 26.5 g of activated alumina (NKHD-24 manufactured by Sumitomo Chemical Co., Ltd., Kiku) arranged in a size of 42 to 200 was stirred at 500°C for 2 hours under a nitrogen atmosphere, and then cooled to 350°C. After that, 2.5 g of potassium hydroxide was added, and the mixture was stirred at the same temperature for 3 hours.

After cooling to 290° C., 2.0 g of potassium metal was added and stirred at the same temperature for 0.5 hour. This was allowed to cool to room temperature to obtain 24 g of solid base A.

(Solid base B) Solid base A was prepared according to the preparation example of solid base A, except that the temperature when adding potassium hydroxide and the subsequent stirring temperature were changed from 350°C to 250°C. Obtained.

(Solid base C) Solid base A was prepared according to the preparation example of solid base A, except that the temperature when adding potassium hydroxide and the subsequent stirring temperature were changed from 350°C to 480'C. I got it.

(Solid base D) In solid base A, the activated alumina was stirred at 580°C for 1 hour, then potassium hydroxide was added at the same temperature, and the procedure was carried out according to the preparation example of solid base A, except that the mixture was stirred at the same temperature. 24.1 g of solid base was obtained.

(Solid base E) Solid base A was carried out according to the preparation example for solid base except that 2.5 g of sodium hydroxide was used instead of potassium hydroxide, and 24.1 g of solid base E was obtained.

(Solid base F) Performed in accordance with the preparation example of solid base A, except that in solid base A, 2.5 g of sodium hydroxide was used in place of potassium hydroxide, and 2.0 g of sodium metal was used in place of potassium metal. A solid base F was obtained.

(Solid base G) Activated alumina with an average center particle size of 80 μm (Jumin Chemical Industry ■
B K-570) 50g was stirred at 500°C for 1 hour under a nitrogen atmosphere, then cooled to 350°C, 5.65g of potassium hydroxide was added, and the mixture was stirred at the same temperature for 3 hours.

Then, after cooling to 290°C, 4.06 g of metallic potassium
was added and stirred at the same temperature for 0.2 hours. This was allowed to cool to room temperature to obtain 55.2 g of solid base G.

(Solid base H) In solid base G, using 4.02 g of metallic potassium,
Solid base H was obtained by following the preparation example of solid base G except that the temperature when adding metallic potassium and the subsequent stirring temperature were changed from 290°C to 350°C.

(Solid base I) Based on the preparation example of solid base G, except that in solid base G, 4.15 g of metallic potassium was used, and the temperature when adding metallic potassium and the subsequent stirring temperature were changed from 290°C to 220°C. Solid base I was obtained.

(Solid base J) In solid base G, 50 g of activated alumina (NKH324, manufactured by Sumima Kagaku Kogyo ■) arranged in a mesh size of 48 to 200.
, potassium hydroxide 4.73 g, metallic potassium 2.2
Solid base J was obtained in accordance with the preparation example of solid base G except that 9 g was used.

(Solid base K) 26.5 g of the same activated alumina used in solid base A and 2.5 g of potassium hydroxide were pulverized and mixed, and this was placed in an alumina crucible and heated at 1200°C for 3 hours in a Matsufuru furnace. After cooling to 200''C, fine powder was obtained by cooling to room temperature in a desiccator under nitrogen atmosphere.

After heating this material to 290°C under a nitrogen atmosphere, 2.0g of metallic potassium was added to it while stirring, and the mixture was heated to 290°C at the same temperature.
．． Stirred for 5 hours. This was cooled to room temperature and solid base K was added.
I got it.

(Solid Base L) A solid base was obtained by following the preparation example for a solid base except that 2.0 g of metallic sodium was used in place of metallic potassium in solid base K.

(Solid base M) For solid base K, the temperature at which it is heated in a Matsufuru furnace is set to 12
A solid base M was obtained in accordance with the preparation example for a solid base except that the temperature was changed from 00°C to 900°C.

Example 1 0.39 g of solid base A and 240 g of 'tamene were placed in a 600 d autoclave equipped with a magnetic stirrer under a nitrogen atmosphere.
After raising the temperature to 105℃ with stirring, 1 ethylene gas was added at the same temperature.
The reaction was carried out for 1.5 hours while supplying at 0 kg/cd-G.

After the reaction, the autoclave was cooled, the catalyst was filtered off, and the reaction solution was analyzed by gas chromatography. The reaction results are shown in Table 1.

Example 2.3 The reaction was carried out in accordance with Example 1, except that the reaction was carried out under the reaction conditions shown in Table 1.

The results are shown in Table 1.

Table 1 TAB=Lert-amylbenzene produced side chain alkyl compounds (mol) Examples 4 to 9,
Comparative Examples 1-2 The procedure of Example 1 was repeated, except that in addition to solid base A, solid bases B-F and L were used, 160 g of cumene was used, and the reaction temperature was 160°C. The reaction results are shown in Table 2.

In Examples 1 to 9, the catalyst was still active after the reaction was completed, and when the reaction was further carried out, the reaction proceeded.

Table 2 Example 11 0.86 g of solid base A and 80 g of cumene were placed in a 300 ml autoclave equipped with a magnetic stirrer under a nitrogen atmosphere, and 120 mff1 of liquefied propylene was pressurized into the autoclave.
Stirring was continued for 6 hours.

After the reaction was completed, the autoclave was cooled, and the reaction solution was analyzed by gas chromatography in the same manner as in Example 1. The reaction results are shown in Table 3.

Example 1O In a 230d autoclave with a magnetic stirrer under a nitrogen atmosphere,
Add 85 g of solid base GO and 88 g of cumene, and while stirring,
After raising the temperature to 162℃, 30kg/ct of ethylene gas was added.
-G was supplied, and the reaction was carried out for 6.5 hours. After the reaction, analysis was performed in the same manner as in Example I, and the cumene conversion rate was 88%.
The TAB selectivity was 100%.

Examples 12 to 15 In Example 11, instead of solid base A, solid base G-
Example 11 except that it was carried out using J and under the conditions shown in Table 3.
This was done in accordance with the. The results are shown in Table 3.

In Examples 11 to 15, the catalyst was still active after the reaction was completed, and when the reaction was further carried out, the reaction proceeded.

Comparative Example 3 8.86 g of anhydrous potassium carbonate and 0.30 g of sodium were calcined in advance at 400° C. for 2 hours under a nitrogen atmosphere in a 200 d autoclave equipped with a magnetic stirrer under a nitrogen atmosphere.
After adding 81.2 g of cumene, the temperature was raised to 190°C, and stirring was continued at the same temperature for 2 hours.

Then cool the autoclave and add liquefied propylene 70#
After injecting ffi, the mixture was stirred at 160'C for 24 hours.

After the reaction, analysis by gas chromatography in the same manner as in Example 1 revealed that the cumene conversion rate was 8.0% and the TMPB selectivity was 81.5%.

Example 16 4.07 g of solid base A and 79.5 g of toluene were placed in a 300s1 autoclave equipped with a magnetic stirrer under a nitrogen atmosphere, and after 70Id of liquefied propylene was pressurized, stirring was continued at 163° C. for 6 hours.

After the reaction, it was analyzed in the same manner as in Example 1. The results are shown in Table 4.

Table 4 IBB=Isobutylbenzene generated side chain alkyl compound (+5ol) Example 17~
20. Comparative Example 4 In Example 16, solid base B- was replaced with solid base A.
The procedure was carried out in accordance with Example 16 except that D, J, and M were used respectively. The results are shown in Table 4.

In Examples 16 to 20, the catalyst was still active after the reaction was completed, and when the reaction was further carried out, the reaction proceeded.

Comparative Example 5 8.45 g of anhydrous potassium carbonate, 0.30 g of sodium, and 8.45 g of anhydrous potassium carbonate and 0.30 g of sodium were heated at 400° C. and calcined for 2 hours under a nitrogen atmosphere in a 200 d autoclave equipped with a magnetic stirrer under a nitrogen atmosphere.
After adding 26.6 g of toluene, stirring was continued at 190° C. for 2 hours.

Next, the autoclave was cooled, 53.2 g of toluene was added, 70 d of liquefied propylene was press-fitted, and the temperature was increased to 160°C.
The mixture was stirred for 6 hours. After the reaction, analysis by gas chromatography in the same manner as in Example 1 revealed that the toluene conversion rate was 3.5% and the IBB selectivity was 88.2%.

Example 21 In a 200d autoclave with a magnetic stirrer under a nitrogen atmosphere,
Add 0.7 g of solid base J and 81 g of toluene and heat to 160°C.
After raising the temperature to , ethylene gas was supplied at 10 kg/cj -G, and stirring was continued at the same temperature for 6 hours.

After the reaction, analysis by gas chromatography in the same manner as in Example 1 revealed that the toluene conversion rate was 28.2%, the n-propylbenzene selectivity was 78.6%, and the 1-ethylpropylbenzene selectivity was 20.9%. Ta.

Claims (1)

[Claims] When producing an alkyl-substituted aromatic hydrocarbon by alkylating an aromatic hydrocarbon having a hydrogen atom at the α-position of the side chain with an olefin, alumina, an alkali metal hydroxide, and an alkali metal are used as a catalyst in an inert gas atmosphere. ,2
1. A method for producing an alkyl-substituted aromatic hydrocarbon, the method comprising using a solid base heat-treated at a temperature of 00 to 600°C.