JP2980760B2 - Process for producing alkenylbenzene and derivatives thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing alkenylbenzene efficiently and safely by reacting an alkylbenzene with a conjugated diolefin in the presence of an alkali metal. More specifically, for example, o-xylene and 1,
5- (o-Tolyl) -pentene, an alkenylbenzene obtained by reaction with 3-butadiene, is cyclized to dimethyltetralin, which is dehydrogenated to dimethylnaphthalene and then oxidized. It is a compound of high industrial value that can be converted to naphthalenedicarboxylic acid useful as a molecular raw material, and the present invention relates to a method for producing such a useful raw material.

[0002]

2. Description of the Related Art A method for producing monoalkenylbenzene by reacting an alkylbenzene with 1,3-butadiene in the presence of an alkali metal has been known (see US Pat. No. 3,244,758).

[0003] However, the above-mentioned method has a disadvantage that a large amount of expensive potassium metal must be used in order to obtain monoalkenylbenzene in a high yield. Further, in order to solve this problem, a method has been proposed in which, when 1,3-butadiene is blown into alkylbenzene to cause a reaction, when metal potassium and metal sodium are used in combination as a catalyst, expensive metal potassium needs to be used in a small amount. (Japanese Patent Publication No. 56-34570, US Patent No. 3766)
288, U.S. Pat. No. 3,953,535).

Further, a method has been proposed in which the production process is improved in which metal potassium is supported on potassium carbonate or alumina and o-xylene and butadiene are reacted in a fixed bed (US Pat. No. 4,990,717).

However, all of these methods use metal potassium directly, and therefore have a high reactivity to air, oxygen, water, etc., and ignite only upon contact with these compounds, which is dangerous for fire safety. In particular, sodium-potassium (Na-K: Nack) alloy is highly active against oxygen and water, ignites on contact with trace amounts of oxygen and water, etc., and coexists with surrounding combustibles (petroleum). It is extremely dangerous.

Further, British Patent No. 1269280 (1972)
(April 6, 2008) describes that diene has a reaction inhibiting effect in an aromatic side-chain alkylation reaction with an olefin using a sodium and anhydrous potassium compound as a catalyst.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to produce alkenylbenzene in high yield without directly using expensive potassium metal having a high risk of ignition. . In addition, by reacting alkylbenzene with, for example, 1,3-butadiene in the presence of a catalyst having high activity and high selectivity for the alkenylation reaction, it is difficult to separate the target product from the target product, thereby producing complicated by-products. And to produce a high-purity target substance, that is, alkenylbenzene, in a high yield. It is another object of the present invention to provide a method for cyclizing the alkenylbenzene to produce an alkyltetralin and a method for dehydrogenating the alkyltetralin to produce an alkylnaphthalene.

[0008]

According to the present invention, an alkylbenzene having at least one hydrogen atom at the α-position to an aromatic ring is reacted with a conjugated diolefin, for example, 1,3-butadiene in the presence of a catalyst. In producing alkenylbenzene, (a) an alkali metal as a catalyst, (b) potassium organic acid R (COOK) _n ... (I) represented by the following formula (I) (R is a hydrogen atom or C ₁ represents a hydrocarbon group or a derivative thereof -C _20, n is used.) and mixed and dispersed treated catalyst represents an integer of 1 to 4, and an environment in which oxygen and water is substantially absent, A process for producing alkenylbenzene and its derivatives, characterized by reacting an alkylbenzene with a conjugated diolefin (for example, 1,3-butadiene).

That is, an alkylbenzene is reacted with a conjugated diolefin to produce alkenylbenzene without substantially allowing oxygen and moisture to exist, and as catalysts (a) an alkali metal and (b) an organic acid By reacting alkylbenzene with 1,3-butadiene in the presence of a catalyst prepared by mixing and dispersing a potassium salt, it is difficult to separate the product from the target product, and the production of complicated by-products is suppressed, and high purity is obtained. A method for producing alkenylbenzene and its derivatives, characterized in that alkenylbenzene is produced in high yield. Hereinafter, the present invention will be described in detail.

The alkylbenzene as a raw material used in the method of the present invention has at least one hydrogen atom at the α-position to the aromatic ring, and preferably has one or two methyl, ethyl, or propyl groups in the benzene nucleus. Etc., and specific compounds include toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, and propylbenzene. Each of these alkylbenzenes is preferably used alone,
When a mixture is used, it becomes difficult to separate the target product from the alkenylbenzenes, which are reaction products, with high purity.

For example, in the reaction between o-xylene and 1,3-butadiene, if alkylbenzene such as toluene, p-xylene, m-xylene, ethylbenzene or the like is mixed as an impurity, it will cause a significant decrease in the purity of the target product. Therefore, the purity of o-xylene is preferably 95% or more, more preferably 98% or more. However, a small amount of hydrocarbon having no alkyl group such as benzene and cyclohexane may be mixed.

Similarly, when toluene, ethylbenzene, m-xylene, or p-xylene is used, the purity of each single product is preferably 95% or more, and more preferably 98% or more, and alkyl groups such as benzene and cyclohexane are used. The incorporation of small amounts of hydrocarbons that do not have is acceptable.

It is preferable that the starting alkylbenzene is dehydrated and used in the reaction. As a dehydration method,
For example, there are methods such as adsorption separation with a suitable drying agent (for example, activated alumina, silica gel, molecular sieves, activated carbon, etc.), cryogenic separation, and dehydration by previously contacting with metal sodium or potassium. The water content in the raw material is preferably as low as possible, and is particularly preferably equal to or less than the measurement sensitivity of the Karl Fischer method, which is a usual method for measuring water content, for example, several ppm or less.

The conjugated diolefin used in the present invention includes 1,3-butadiene, isoprene and the like. The 1,3-butadiene may be produced by any method, and the purity of the 1,3-butadiene may be any. For example, crude butadiene obtained by dehydrogenation of butane or butene can be used as it is, or 1,3-butadiene obtained by purifying the crude butadiene by a method such as extraction.

It is preferable that 1,3-butadiene is used in the reaction after dehydration. Examples of the dehydration method include adsorption separation using a suitable drying agent such as activated alumina, silica gel, molecular sieves, activated carbon, or the like, or cryogenic separation. The lower the water content in 1,3-butadiene is, the more preferable it is.

In the present invention, the catalyst used for the reaction between the alkylbenzene and the conjugated diolefin is a catalyst obtained by mixing and dispersing (a) an alkali metal and (b) a potassium salt represented by the following formula (1). . R (COOK) _n (I) (R represents a hydrogen atom or a C _{1 to} C ₂₀ hydrocarbon group or a derivative thereof, and n represents an integer of 1 to 4.)

The alkali metal is preferably sodium,
The higher the purity, the better, but it may contain a small amount of metals such as potassium, calcium, magnesium, and aluminum. The purity is preferably 90% or more, and preferably 99% or more.

The amount of sodium metal used may be in any ratio with respect to 1 mole of alkylbenzene,
Usually, it may be 2 mmol or more. If the amount is less than 2 mmol, the reaction is extremely slow, which is not preferable. On the other hand, if the use ratio is too large, the selectivity and yield of the target product may be reduced. Therefore, the upper limit is preferably 300 mmol or less.

(Dispersion activating agent) The potassium salt of an organic acid used in the present invention is a compound represented by the following formula (I). R (COOK) _n (I) (R represents a hydrogen atom or a C _{1 to} C ₂₀ hydrocarbon group or a derivative thereof, and n represents an integer of 1 to 4.)

In the above formula (I), R represents an alkyl group having 1 to 20 carbon atoms, an alkylene group, an alkenyl group,
Alkenylene groups and the like can be mentioned.

Examples of the alkyl group include a methyl group, a propyl group, a heptyl group and a hexyl group. Examples of the alkylene group include a methylene group, an ethylene group, and a propylene group. Examples of the alkenyl group include a propenyl group and a pentenyl group. Alkenylene groups include vinylylene groups,
And a propenylene group.

R is a substituted or unsubstituted phenyl group, phenylene group, naphthyl group, naphthylene group or naphthalenetriyl group.

These compounds include potassium formate,
Potassium acetate, potassium propionate, potassium n-butyrate, potassium isobutyrate, potassium valerate, potassium caproate, potassium caprylate, potassium n-decanoate,
Potassium laurate, potassium oleate, potassium palmitate, potassium oxalate, potassium malonate, potassium fumarate, potassium benzoate, potassium phthalate, potassium terephthalate, potassium methyl phthalate, potassium trimellitate, potassium naphthylate, etc. Among them, potassium salts of organic acids composed of C ₁ -C ₁₀ are preferred from the viewpoint of the K content by weight. It is preferable that these organic acid potassium salts are sufficiently dried and dehydrated before use.

The organic acid potassium salt used in the present invention may be used in an amount necessary for allowing 1 mmol or more of potassium ions to exist in 1 mole of alkylbenzene, and usually, as potassium atom of organic acid per mole of alkylbenzene. It is sufficient that the amount is 3 mmol or more, but these compounds are more often used to function as a dispersant.

For example, 5 to 500 mmol of potassium acetate is used per 1 mol of o-xylene. When the amount of the organic acid potassium salt is 5 mmol or less per 1 mol of alkylbenzene, the reaction is slow, and when it exceeds 500 mmol, the yield and selectivity of the target product decrease. Therefore,
Preferably, it is used in a range of 10 mmol to 300 mmol.

(Preparation of Catalyst) In the present invention, the catalyst is prepared by mixing and dispersing (a) metallic sodium with (b) a potassium salt of an organic acid represented by the formula (I).

The mixing and dispersing treatment is performed in an inert gas such as nitrogen, argon, helium, hydrogen, etc., and is employed in a so-called wet dispersing method of dispersing using an inert solvent and in a dry dispersing method using no solvent. However, in the present invention, the wet dispersion heat treatment method of dispersing in the above-mentioned solvent is preferably performed from various viewpoints.

In the wet dispersion method, metallic sodium and potassium organic acid are stirred at a high speed in an inert solvent, finely dispersed, and heat-treated. For example, when 3% by weight of metallic sodium in a dispersion catalyst is subjected to dispersion treatment, 3 parts of metallic sodium and 9 parts of potassium salt of an organic acid as a dispersing activator are treated.
7 parts in 100 parts of solvent o-xylene at the same time
The mixture is stirred at 0 to 160 ° C. and stirred at a high speed. However, a dispersion prepared by dispersing the mixture at an appropriate mixing ratio is prepared in advance, and a solvent is added to the dispersion or the formula is further added by adding potassium alkoxide. It can also be carried out by a method of causing.

As the inert solvent, n-octane, n-nonane, decane, undecane, dodecane and the like have a carbon number of 8 to 8.
20 having a boiling point of 100 to 230 ° C., preferably 13
Paraffin at 0 to 200 ° C. is exemplified, and among them, it is most industrially preferable to use alkylbenzene used as a reaction raw material.

The catalyst thus uniformly dispersed is prepared by adding a mixture of an alkylbenzene and a catalyst before introducing and reacting a conjugated diolefin, for example, 1,3-butadiene.
Pre-treatment and reaction at 0 to 200 ° C for 1 to 5 hours can improve selectivity and activity.

The catalyst used in the present invention in which (a) an alkali metal is dispersed and mixed with (b) a potassium salt of an organic acid can be used in combination with a carbonate such as potassium carbonate and sodium carbonate. That is, at the time of dispersing and mixing the alkali metal and the organic acid potassium salt, the mixture may be prepared in the presence of a carbonate. Examples of the carbonate include sodium carbonate, potassium carbonate, magnesium carbonate, calcium carbonate and the like.

In the method of the present invention, alkylbenzene and 1,3
The reaction with butadiene is carried out in an environment substantially free of moisture and oxygen. Therefore, it is desirable that the raw materials introduced into the reaction system from outside the system, that is, the alkylbenzene and the conjugated diophine are dehydrated as described above. Furthermore, the space in the reaction system is filled with a dry inert gas such as dry nitrogen or dry argon under the condition that oxygen or water is not substantially present, or the space is filled up under the reaction conditions higher than the boiling point of alkylbenzene. It is desirable to fill with steam such as alkylbenzene.

In the present invention, the reaction is preferably carried out at a temperature in the range of 100 to 200 ° C. Reaction temperature 100 ° C
In the following, the reaction time is prolonged, and if it exceeds 200 ° C., the amount of by-products increases, which is not preferable. The preferred reaction temperature is 1
10 to 180 ° C. The reaction molar ratio of 1,3-butadiene to alkylbenzene can be appropriately selected under ordinary conditions. For example, alkylbenzene: 1,3-butadiene = 1: 0.001-0.5, preferably 1: 0.
It can be carried out in the range of from 01 to 0.3, particularly preferably from 1: 0.05 to 0.2.

The reaction time is in the range of 0.05 to 10 hours. The reaction time depends on the amount of catalyst (g-catalyst / g
-Alkylbenzene), catalyst composition (g-metal sodium / g-organic acid potassium salt), reaction temperature (° C), and the ratio of alkylbenzene to 1,3-butadiene (g-alkylbenzene / g-1,3-butadiene) respectively It is relevant, and an appropriate time is adopted depending on the purity of the target product and the use mode of the catalyst, for example, the presence or absence of circulating use. In general, the reaction time becomes longer as the numerical values of the above factors decrease, but the preferable reaction time is 0.2 to 10 hours, particularly preferably 0.3 to 0.3 hours.
~ 5 hours.

The reaction is a batch reaction in which the starting materials alkylbenzene, 1,3-butadiene and a catalyst are simultaneously charged and reacted. First, an alkylbenzene and a catalyst are charged, and then 1,3-butadiene is quantitatively determined with the passage of reaction time. Any of a semi-batch reaction to be introduced and a continuous reaction to continuously introduce an alkylbenzene, 1,3-butadiene and a catalyst into a reactor may be adopted, and a suitable combination thereof may be used. A reaction or a continuous reaction is preferred.

There are two types of continuous reactions. That is, a method of carrying out a reaction while continuously supplying alkylbenzene and 1,3-butadiene in predetermined amounts while stirring and dispersing a catalyst in a reaction system, and a method of dispersing a catalyst of metal sodium and an organic acid potassium salt using alumina or the like. Continuously flowing alkylbenzene through a fixed bed of catalyst supported on solid fine powder of
There is a method of performing a continuous reaction while introducing 1,3-butadiene into an alkylbenzene.

In the continuous reaction system, any of a tubular reactor, a column reactor and a tank reactor may be used. A preferred method for continuous reaction is to provide a plurality of reaction zones,
This is a so-called cross-flow type continuous system in which 1,3-butadiene is quantitatively introduced into each reaction zone.

The reaction operation may be carried out as long as the alkylbenzene and 1,3-butadiene can be sufficiently mixed in the presence of the catalyst. There is no particular limitation.
In the introduction method in which 3-butadiene is introduced, a resinous or gum-like substance presumed to be a heavy substance of 1,3-butadiene adheres to the vicinity of the introduction port of 1,3-butadiene, and tends to cause a clogging phenomenon. Therefore, a mixed phase of 1,3-butadiene and alkylbenzene, for example, a liquid phase mixture of liquid butadiene and alkylbenzene, a gas phase of gaseous 1,3-butadiene and liquid alkylbenzene,
A method in which 1,3-butadiene and alkylbenzene are introduced in the form of a liquid mixture or the like is preferable.

Alternatively, clogging can be prevented by supplying 1,3-butadiene to the reaction space to cause an absorption reaction on the surface of the reaction solution where the catalyst is present. In addition, when the butadiene is introduced, the stirring effect can be increased at the same time as blowing with the carrier gas. Inert gas from which oxygen and moisture have been removed as carrier gas,
For example, nitrogen, argon, and hydrogen are suitable.

Further, the reaction can be preferably carried out by providing appropriate stirring. However, 1,3-butadiene can be introduced into the reaction system in a gas phase, and the gas can have a stirring effect. The stirring is desirably of a strength necessary for uniformly dispersing the catalyst in the reaction system and for uniformly mixing the reaction raw material and the reaction product. When the reaction is carried out in a liquid phase dispersion reaction system, after the reaction, the used catalyst can be separated from the reaction product system by a known means such as centrifugal sedimentation, gravity sedimentation, or a liquid-solid phase at a lower temperature. Any known means such as separation of the solid phase from the mixture, such as filtration and centrifugation, may be used. The separated catalyst can be recycled to the reaction system.

According to the method of the present invention, toluene and 1,3-
In the reaction of butadiene, 5-phenyl-pentene is synthesized. In the reaction of o-xylene and 1,3-butadiene, 5- (o-tolyl) -pentene is produced. In the reaction of p-xylene and 1,3-butadiene, Is 5- (p-tolyl) -pentene, 5- (m-tolyl) pentene in the reaction of m-xylene and 1,3-butadiene, and 5- (phenyl) -hexene in the reaction of ethylbenzene and butadiene. Each is synthesized.

As described above, the alkenylbenzene as the target product of the present invention is subjected to a cyclization reaction and then dehydrogenation to obtain compounds useful as raw materials for pharmaceuticals and polymer materials, that is, monoalkylnaphthalene and dialkylnaphthalene. Can be

In this case, the purity of pentene or hexene when cyclizing phenyl-pentene, phenyl-hexene or tolyl-pentene becomes a problem. That is, phenyl-pentene, phenyl-hexene, tolyl
The so-called aryl alkene olefinic double bond of pentenes has a position of 1 or 2, but in a conventionally known method, isomers having different positions of the olefinic double bond, for example, a reaction between o-xylene and butadiene. Then 5-
(O-tolyl) -pentene- (1), 5- (o-tolyl) -pentene- (2), 5- (o-tolyl) -pentene- (3), 5- (o-tolyl) -pentene- (4) and the like are produced as by-products in a considerable amount and are mixed. In other phenylpentene, phenylhexene, and tolylpentene synthesized by the reaction of toluene, ethylbenzene, p-xylene, m-xylene and butadiene, isomers having different positions of the olefinic double bond are by-produced and mixed.

Of these isomers, those in which the olefinic double bond is in the 1 or 2 position can be cyclized and converted to alkyltetralin, while the others are not only not converted to alkyltetralin, but also It reacts with the product alkyltetralin to become a high-boiling product, which lowers the yield of the desired product.

Furthermore, the olefinic double bond is converted to 3,4,5
It is very difficult to remove the isomer at the position (1), for example, a reaction mixture of o-xylene and 1,3-butadiene (the objective product is 5- (o-tolyl) -pentene-
(2) and 5- (o-tolyl) -pentene- (1)) are rectified at a reflux ratio of 20 using rectification with 50 theoretical plates or the like. The body can hardly be separated.

On the other hand, the reaction product obtained by the method of the present invention has such a feature that there are very few such difficult-to-separate side reactions, and the yield of the cyclization reaction product is also extremely high.

Alkenylbenzene is cyclized to alkyltetralin by a method known per se, that is, contact with an acid catalyst such as sulfuric acid, solid phosphoric acid, or silica alumina at a temperature of 100 to 250 ° C. for 10 seconds to 10 hours. Can be.

Alkyltetralin can be prepared in a manner known per se, ie, alumina-chromia, Pt / Al ₂ O ₃
For 5 seconds to 10 at a temperature of 350 to 450 ° C.
It is dehydrogenated by contacting for an hour to obtain an alkylnaphthalene.

The alkylnaphthalene can be prepared by a method known per se, that is, by using a solid acid catalyst such as silica-alumina, ZSM-5, Y-type zeolite, H-type mordinite and the like.
The isomerization can be performed by catalyzing at a temperature of 〜450 ° C. for 5 seconds to 10 hours. For example, 1,5-dimethylnaphthalene can be changed to 2,6-dimethylnaphthalene.

According to the present invention, dimethylnaphthalene, a compound useful as a raw material for a polymer material, can be produced from alkylbenzene as follows.

That is, for example, o-xylene and 1,3-
Butadiene is reacted with a catalyst prepared by dispersing metallic sodium with an organic acid potassium salt to produce 5- (o-tolyl) pentene, and then the 5- (o-tolyl)
The pentene is cyclized by a method known per se to give 1,5-
After producing dimethyltetralin, the 1,5-dimethylnaphthalene can be isomerized to produce 2,6-dimethylnaphthalene.

Further, by oxidizing the 2,6-dimethylnaphthalene, naphthalene-2,6-dicarboxylic acid can be produced.

[0053]

The reaction product obtained by the method of the present invention has very few by-products which are difficult to separate, and
The yield of the cyclization reaction product is also very high.

According to the method of the present invention, alkylbenzene and 1,3-butadiene are used in the presence of a catalyst obtained by dispersing an alkali metal with a potassium salt of an organic acid as a catalyst without substantially allowing oxygen and moisture to be present. By reacting with the metal, there is a high risk of expensive ignition
No direct use of potassium (Na-K: Nack) alloy, high activity and high selectivity in the alkenylation reaction, and therefore, it is difficult and complicated to separate from the target product, and the generation of by-products is suppressed. However, it has become possible to produce a high-purity target product in a high yield. The catalyst used in the method of the present invention has an advantage that the catalyst can be easily separated without the trouble of separation as in the case of a knack, and the cost is low.

[0055]

The present invention will be described below in detail with reference to examples. Needless to say, the present invention is not limited to the embodiment. In the following Examples and Comparative Examples, the yield and purity of the target product follow the following definitions. Further, “parts” simply means “parts by weight”.

(Yield and Purity) After filtering the entire reaction mixture at room temperature, about 500 g was filtered at 22 mmHg (abs) using a Widmer rectification column.
The distillation was carried out under reduced pressure in (1) to separate into a fraction having a rectification tower top temperature of 75 ° C or lower, a fraction having a temperature of 75 to 170 ° C, and a residue. Then, a fraction at 75 to 175 ° C. was collected as an alkenylate obtained by alkenylating xylene with 1,3-butadiene. The alkenylate yield of the entire reaction mixture was calculated from the proportion of the alkenylate fraction in the sample.

The alkenylated fraction was analyzed by gas chromatography to determine the contents (% by weight) of 5- (tolyl) -pentene (2) and 5- (tolyl) pentene (1). The product yield was calculated. Incidentally, the unreacted xylene contained only 0.1% by weight or less in the alkenylated product fraction.

Similarly, the reaction product of toluene and butadiene is the same for 5-phenylpentene (1) and 5-phenyl-
The pentene (2) content was determined, and the yield of the desired product was calculated.

The yield when xylenes and ethylbenzene were used as the alkylbenzene was calculated by the following equation.

[0060]

(Equation 1)

The reaction product of toluene and butadiene was calculated by the following equation.

[0062]

(Equation 2)

[0063]

Example 1 (A) Preparation of Dispersion of Fine Particles of Metallic Sodium After heating and refluxing in the presence of metallic sodium in advance, it is distilled and further dehydrated with molecular sieve, and contains substantially no water. After blowing dry high-purity nitrogen (oxygen content 1 ppm or less, moisture content 0.1 ppm or less) into 500 parts of o-xylene to drive out dissolved oxygen and remove it, a predetermined amount of metallic sodium (purity 99.9%) is added. The mixture was emulsified and dispersed under an atmosphere of nitrogen at 110 to 120 ° C. for 30 minutes using an emulsifying and dispersing machine to prepare an emulsified dispersion of metallic sodium.

(B) Preparation of Metal Sodium / Organic Acid Potassium Salt / Dispersion Catalyst A predetermined amount of an organic acid potassium salt is added to the emulsified dispersion of sodium metal prepared as described above,
The mixture was stirred and heated and dispersed at １４144 ° C. for 1 hour to prepare a metal sodium / organic acid potassium salt dispersion catalyst.

(C) Synthesis reaction of 5- (o-tolyl) pentene o-xylene dehydrated and purified as described above was added to the catalyst dispersion prepared in the above (B) under a nitrogen atmosphere with stirring, and Table 1
After stirring for 1 hour at 140 to 145 ° C., 1,3-butadiene was introduced at a ratio of 0.1 mol to 1 mol of o-xylene and reacted.

After completion of the reaction, a cooler was immediately cooled to 100 ° C.
While maintaining the temperature at 100 ° C., stirring was stopped and the mixture was allowed to stand for 30 minutes to separate a reaction product mixture into a catalyst and a liquid phase of a target substance. 22mmHgo for 5- (o-tolyl) pentene
bs. The yield and purity of 5- (o-tolyl) pentene obtained by distillation under reduced pressure are shown in Table 1.

[0067]

[Table 1]

[0068]

Examples 2 to 8 and Comparative Examples 1 to 6 Further, Examples 2 to 8 and Comparative Examples 1 to 6 were carried out under the same conditions as in Example 1 except that the catalyst composition, amount, reaction temperature and reaction time were variously changed. Tables 1 and 2 show the results obtained by performing the reaction.

[0069]

[Table 2]

As can be seen from Tables 1 and 2, according to the method of the present invention, 5- (o-tolyl) pentene having high yield and high purity can be obtained.

[0071]

Examples 9 to 13 and Comparative Examples 7 and 8 In Example 1, p-xylene was used in place of o-xylene to give 1,3
-Alkenylation reaction with butadiene was performed. The preparation and reaction of the catalyst were carried out under the same conditions and operating method as in Example 1. Table 3 shows the results. As can be seen from Table 3, according to the method of the present invention, high-purity 5- (p-tolyl) pentene can be obtained in high yield.

[0072]

[Table 3]

[0073]

Example 14 (A) Preparation of Catalyst In this example, a method of melting and dispersing metallic sodium was performed. That is, sodium metal sodium carbonate calcined and dehydrated at 450 ° C. for 5 hours was added in a weight ratio of 63: 7 to 1
After high-speed dispersion treatment at 50 ° C. for 60 minutes, the mixture was cooled to 120 ° C., 1000 parts of dehydrated ethylbenzene was added, and 30 parts of potassium oxalate was added to the dispersion dispersed under high-speed stirring.
The catalyst was prepared by treating at 130 to 136 ° C for 60 minutes.

(B) Synthesis reaction of 5- (phenyl) -hexene To the catalyst prepared in the above (A), 2,000 parts of ethylbenzene dehydrated and purified as in Example 1 was added, and the reaction was carried out at 135 to 140 ° C.
, 150 parts of 1,3-butadiene was introduced over 1.5 hours and reacted. After completion of the reaction, the mixture was immediately cooled to 80 ° C., stirring was stopped while maintaining the temperature, and the mixture was allowed to stand for 30 minutes.
The reaction product liquid was separated into a catalyst and a target liquid phase. The desired product, 5-phenyl-hexene, was distilled under a reduced pressure of 25 mmHg abs. The yield and purity were determined. As a result, the purity was 98.5.
% And the yield was 88.9%.

[0075]

Example 15 Using a metal sodium-potassium formate dispersion treatment catalyst prepared under the same conditions as in the operation method of Example 14, toluene and 1,3 were added at a reaction temperature of 105 to 115 ° C.
-Reaction of butadiene was performed. As a result, 5-phenyl-pentene having a purity of 99.2% was obtained with a yield of 85%.

[0076]

Embodiment 16 This is an example of synthesizing 2,6-dimethylnaphthalene by a cyclization reaction, a dehydrogenation reaction and an isomerization reaction of 5- (o-tolyl) -pentene.

(A) Synthesis of 1,5-dimethyltetralin by cyclization reaction of 5- (o-tolyl) -pentene 5- (o-tolyl) -pentene having a purity of 99.0% obtained in Example 1 A cyclization reaction was carried out using a 10% solution of toluene. Using solid phosphoric acid as catalyst, reaction temperature 15
As a result of carrying out in a nitrogen atmosphere at 0 to 200 ° C., the conversion of the raw material was 100%, and the selectivity for the production of 1,5-dimethyltetralin, which is a cyclized product, was 95% or more.

(B) Synthesis of 1,5-dimethylnaphthalene by dehydrogenation of 1,5-dimethyltetralin Dehydration was carried out using a 10% toluene solution of 1,5-dimethyltetralin obtained by the method (A). An elementary reaction was performed.
As a result of dehydrogenation at 400 ° C. in a hydrogen atmosphere using a 0.3% Pt / Al ₂ O ₃ catalyst as a dehydrogenation catalyst, 1,5-
1,5-dimethylnaphthalene was obtained with a conversion of dimethyltetralin of 100% and a selectivity of 1,5-dimethylnaphthalene of 97%.

(C) Synthesis of 2,6-dimethylnaphthalene by isomerization of 1,5-dimethylnaphthalene 1,5-dimethylnaphthalene obtained by dehydrogenation according to the method (B) isomerized to give 2,2-dimethylnaphthalene. An experiment for synthesizing 6-dimethylnaphthalene was performed.

Results of isomerization reaction using a 10% toluene solution of 1,5-dimethylnaphthalene at a temperature of 350 to 400 ° C. in the presence of an alumina dispersion catalyst containing 30% of H-type mordenite under a nitrogen atmosphere in a nitrogen atmosphere. , 1,5-dimethylnaphthalene 10%, 2,6-dimethylnaphthalene 43
%, 1,6-dimethylnaphthalene 44%, and a mixture of other naphthalene compounds 3% were obtained. When this was crystallized and separated, 50% of 98% pure 2,6-dimethylnaphthalene was recovered.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C07C 5/367 C07C 5/367 13/48 13/48 15/24 15/24 // C07B 61/00 300 C07B 61/00 300 (58) Field surveyed (Int.Cl. ⁶ , DB name) C07C 15/44 B01J 31/04 C07C 2/72 C07C 5/27

Claims (12)

(57) [Claims] 1. An alkenylbenzene is produced by reacting an alkylbenzene having at least one hydrogen atom at the α-position with respect to an aromatic ring with a conjugated diolefin in the presence of a catalyst. (B) a potassium salt of an organic acid represented by the following formula (I): R (COOK) _n (I) (R represents a hydrogen atom, a C _{1 to} C ₂₀ hydrocarbon group or a derivative thereof, and n represents An alkenyl benzene, wherein an alkylbenzene and a conjugated diolefin are reacted in an environment substantially free of oxygen and water using a catalyst mixed and dispersed with And a method for producing the derivative thereof. 2. The method according to claim 1, wherein the alkylbenzene is any one selected from toluene, ethylbenzene, propylbenzene, o-xylene and p-xylene. 3. The method according to claim 1, wherein the conjugated diolefin is 1,3-butadiene or isoprene. 4. The method according to claim 1, wherein (a) the alkali metal is sodium. 5. The method according to claim 1, wherein the acid residue of the organic acid potassium salt is an aliphatic acid,
The production method according to claim 1, wherein the production method is an aromatic acid. 6. The method according to claim 1, wherein the mixing and dispersing of (a) an alkali metal and (b) a potassium salt of an organic acid is performed in an inert solvent. 7. As an inert solvent, alkylbenzene,
The method according to claim 6, wherein a paraffinic hydrocarbon having a boiling point of 100 to 230C, preferably 120 to 200C, having 8 to 20 carbon atoms is used. 8. The method according to claim 1, wherein the mixing and dispersing of (a) an alkali metal and (b) a potassium salt of an organic acid is performed in an inert gas atmosphere. 9. The method according to claim 8, wherein at least one selected from nitrogen, helium, argon and hydrogen is used as the inert gas. Upon 10. distributed processing, further carbonate Shio及beauty /
Or any one Kouki mounting method of manufacturing of claim 1-9 using a catalyst prepared by Coexistence of hydroxides. 11. A method for producing alkyltetralin, comprising cyclizing alkenylbenzene obtained by the method according to claim 1. 12. A method for producing an alkylnaphthalene, comprising dehydrogenating an alkyltetralin obtained by the method according to claim 12.