JPH01301645A - Production of carboxylic acid aryl esters and catalyst used in said production process - Google Patents

Abstract

PURPOSE:To obtain the subject compound in high yield and selectivity, keeping excellent catalytic activity, without lowering the yield of phenolic compounds, by reacting an aromatic hydrocarbon with a carboxylic acid and molecular oxygen in the presence of a specific palladium-based catalyst. CONSTITUTION:The objective compound is produced by reacting a carboxylic acid (e.g., acetic acid) with an aromatic hydrocarbon (preferably benzene or naphthalene) and molecular oxygen at 100-350 deg.C, preferably 129-250 deg.C under normal pressure - 100 atm in the presence of a catalyst produced by supporting a catalyst component containing a palladium component and a gallium component on a carrier. Preferably, the molar ratio of the gallium component to the palladium component is 0.1-5,000, especially 1-2,000 in terms of metal and the amount of the palladium component supported on the carrier is 0.001-10wt.%, especially 0.01-5wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing aryl carboxylic acid esters, and more specifically, the present invention relates to a method for producing aryl carboxylic acid esters. It relates to a method for producing carboxylic acid aryl esters with high selectivity and high yield by reacting in the presence of the present invention.

The present invention also relates to a palladium-based catalyst used in the method for producing carboxylic acid aryl esters as described above.

Technical background of the invention and its -1 Conventionally, as a method for producing aryl carboxylic esters, aryl carboxylic esters are produced by reacting aromatic hydrocarbons, carboxylic acids, and molecular oxygen in the presence of a catalyst. Is there a way to get it? The catalyst used in the above reaction is listed in the Periodic Table of Elements.
Noble metals of the group IA and IB of the periodic table are effective, and catalysts are already known in which palladium or its compounds are combined with salts of metals from groups 1A and 1IB of the periodic table.

In addition, attempts have been made to produce carboxylic acid aryl esters by blending co-catalysts with noble metals such as palladium and platinum to obtain catalysts with higher activity than the above catalysts.
Various methods have been used in the past.

For example, in Japanese Patent Publication No. 48-18219, benzene, a saturated aliphatic carboxylic acid, and molecular oxygen are reacted in the presence of a catalyst in which metal Bi, Te, Sb, or Se is added as a cocatalyst to palladium. JP-A-51-8188 teaches a method for producing phenyl esters and phenol using palladium as a cocatalyst. A catalyst for the production of carboxylic acid esters is taught, which is prepared by adding and supporting on a carrier.

Furthermore, JP-A-52-77892 discloses a catalyst for producing carboxylic acid phenyl ester, which is prepared by adding antimony as a co-catalyst and an alkali metal sulfonate as an activator to palladium and supporting it on a carrier. JP-A-61-212527 teaches that benzene, carboxylic acid, and molecular oxygen are reacted in the presence of a catalyst consisting of palladium carboxylate, antimony carboxylate, and carboxylic acid. Methods of making phenyl esters and phenols are taught. Furthermore, Japanese Patent Publication No. 49-34973 discloses that benzene, a saturated carboxylic acid, and molecular oxygen are reacted in the presence of a catalyst consisting of palladium, zinc, cadmium, or a neutral or basic carbonic acid salt of a rare earth element. A method for producing carboxylic acid phenyl esters is taught.

The present inventors have found that aromatic hydrocarbons, carbonic acids, and molecular oxygen can be reacted with high selectivity and yield using a catalyst in which a catalyst component containing a palladium component and a gallium component is supported on a carrier. The present inventors have discovered that carboxylic acid aryl esters can be obtained at a relatively low temperature, and have completed the present invention.

The present invention provides high selectivity and high yield by using a specific catalyst when producing carboxylic acid aryl esters by reacting aromatic hydrocarbons, carboxylic acids, and molecular oxygen. The object of the present invention is to provide a method for producing aryl carboxylic acid esters, which can produce aryl carboxylic acid esters.

In addition, the present invention produces carboxylic acid aryl esters by reacting aromatic hydrocarbons, carboxylic acids, and molecular oxygen.
The purpose of the present invention is to provide a highly active palladium-based catalyst which is particularly preferably used in reactions to produce carboxylic acid aryl esters and which can produce carboxylic acid aryl esters with high selectivity and high yield.

Summary of the Invention The method for producing aryl carboxylic acid esters according to the present invention comprises a method for producing an aromatic hydrocarbon, a carboxylic acid, and a molecule in the presence of a catalyst comprising a catalyst component containing a palladium component and a gallium component supported on a carrier. It is characterized by reacting with oxidized oxygen.

Further, the catalyst for producing aryl carboxylic acid esters according to the present invention is characterized in that a catalyst component containing a palladium component and a gallium component is supported on a carrier.

For light! ``U1 Box is a Tomo.'' Hereinafter, the method for producing aryl carboxylic acid esters according to the present invention and the catalyst used in this method will be specifically explained.

Specific examples of aromatic hydrocarbons used in the present invention include benzene, toluene, xylene, ethylbenzene,
↑-butylbenzene, p-di-1-hexylbenzene,
Naphthalene, 2-methylnaphthalene, anthracene, etc. are used, and benzene and naphthalene are particularly preferably used.

The carboxylic acid used in the present invention has 10 carbon atoms or 10 carbon atoms.
The following carboxylic acids are used, specifically acetic acid,
Lower carbonic acids such as propionic acid are preferably used.

In the production method of the present invention, the aromatic hydrocarbon/carboxylic acid molar ratio used can vary over a wide range, but the preferred aromatic hydrocarbon/carboxylic acid molar ratio is usually 1.10.
．． It is within the range of 1 to 1/100.

Molecular oxygen The molecular oxygen used in the present invention includes pure oxygen,
Alternatively, oxygen diluted with an inert gas such as nitrogen or argon may be used.

In the production method of the present invention, the amount of molecular oxygen in the reaction system can be changed arbitrarily.

The catalyst used in the present invention contains a palladium component as a main component.

The starting material for the palladium component is not particularly limited, and any palladium compound that is normally used in preparing a supported palladium catalyst may be used. Specifically, palladium acetate, palladium chloride, etc. palladium,
Palladium nitrate, palladium sodium chloride, etc. are used.

In the present invention, the palladium compound as described above is supported on a carrier by a conventional method, and the palladium component supported on the carrier is 0001 to 10% by weight, preferably 0.01 to 5% by weight in terms of palladium metal. %Used in open flames.

Specifically, the carrier used in the present invention includes alumina, silica, silica/alumina, carbon, diatomaceous earth, clay, magnesia, anionic clay (hydrotalcites), zeolite 1~, etc. However, alumina, silica, zeolite, etc. are preferably used.

In addition to the palladium component described above, the catalyst used in the present invention contains a gallium component as a promoter.

The starting materials for the gallium component are not particularly limited, and include simple metals, salts such as carboxylates, nitrates, hydroxides, oxides, and halides, complex salts, organometallic compounds,
and mixtures thereof are used.

The above-mentioned gallium component constituting the catalyst used in the present invention is 0.1 to 5000 mol in terms of gallium metal per 100 mol of palladium component (palladium metal equivalent),
Preferably it is used in an amount of 1 to 2000 mol.

In addition to the palladium component and the above-mentioned gallium component, the catalyst used in the present invention includes components conventionally used as catalysts in the reaction related to the present invention, such as gallium acetate, sodium acetate, sodium phosphate, gallium hydrogen sulfate,
Alkali metal salts such as gallium methanesulfonate and lithium propionate, carboxylic acid salts such as diminutive acetate, cadmium acetate, and chromium acetate can be appropriately included as additional components.

The additional components as mentioned above are 0.1 to 0.1 to 100 moles of palladium component (palladium metal equivalent).
It is used in an amount of 5000 mol, preferably 1 to 2000 mol.

In the present invention, it is preferable to add a gallium component as an additional component.6 The method for preparing the catalyst used in the present invention is not particularly limited, and may be a conventionally known method of supporting a catalyst component on a carrier, such as the so-called Impregnation methods (immersion methods), ion exchange methods, etc. are preferably used.

The solvent used in the above impregnation method or ion exchange method is capable of dissolving the starting gallium component, and
A solvent that does not dissolve the carrier is used.

After the catalyst component is supported on the carrier by the above-described method, the solvent is distilled off by performing operations such as tecantation, filtration, heating or heating under reduced pressure according to a conventional method.

In the production method of the present invention, the reaction between aromatic hydrocarbons, carboxylic acids, and molecular oxygen is carried out in a gas phase or a gas-liquid mixed phase in the presence of the above catalyst. In the present invention, a reactor capable of continuous reaction in a gas phase or gas-liquid mixed phase state, such as a fixed bed flow reactor or a fluidized bed flow reactor, is used.

By using the reactor as described above, the total failure rate of the target reaction product can be increased.

The reaction temperature is usually 100-350'C5, preferably 12
The temperature is 9 to 250°C, and the reaction pressure may be normal pressure or elevated pressure, preferably normal pressure to 100 atm.

In addition, the contact time between the raw materials and the catalyst entering the reaction system is not particularly limited, but it depends on the load of the reactant flow and the size of the reactor, and is usually within the range of 0.01 to 1000 seconds. .

Effects of the Invention In the method for producing aryl carboxylic acid esters according to the present invention, when producing aryl carboxylic esters by reacting an aromatic hydrocarbon, a carboxylic acid, and molecular oxygen, in addition to the palladium component, gallium Since we use a specific palladium-based catalyst that has a catalyst component supported on a carrier, we can produce carboxylic acid aryl esters with high selectivity and yield without reducing the yield of phenols. The effect is that it can be done.

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 [Preparation of catalyst] 0.94 gallium (I) oxide in 100 ml of acetic anhydride
．． g (5 mmol) and refluxed for about 80 hours. Add 200 [111 ml] of glacial acetic acid to the resulting mixture.
After adding the mixture, the mixture was kept at 60 to 80°C, and the solid content was filtered out using filter paper.

Dissolve 0.4.5 g (2 mmol) of palladium acetate in the obtained P solution at 60 to 80°C, and then add dried activated alumina (particle size of #8 to #14 mesh) to this solution.
30g was added and stirred at 60-80°C for 4 hours. This solution was then allowed to stand overnight at room temperature and then heated under reduced pressure for 8 hours.
The volatile components were distilled off at 0°C to obtain a mixture.

Next, add 059 g of gallium acetate to 1.00 ml of glacial acetic acid (
A solution containing 6 mmol) was added to the above mixture and stirred for 2 hours, then volatile components were distilled off at 80°C under reduced pressure, and the resulting solid was heated at 115°C and 380 m
Volatile components were removed under the conditions of m J (Q).

Next, this solid was passed through a #42 mesh sieve to remove powder components to obtain a solid catalyst 35.8], f.

The results of elemental analysis of the obtained solid catalyst were as follows.

Pd: 0.35% by weight, Ga: 0.04% by weight: 0.
28% by weight Ga/Pd (molar ratio): O, 1,7 /Pd (molar ratio) = 22 [Synthesis of phenyl acetate and phenol] Above catalyst 30
oat (25.88 g) was placed in a Pyrex glass reaction tube with an inner diameter of 27 mm, and a preheated mixed gas with a benzene/acetic acid/oxygen/nitrogen molar ratio of 1/310.46/1.84 was passed through the reaction tube. temperature 200°C
Continuous reaction was carried out under the conditions of 1 contact with a toucher - 13 = time of 475 seconds.

Next, the obtained product was analyzed using liquid chromatography to determine the yields of phenyl acetate and phenol.

The results are shown in Table 1.

In Example 1, the conditions for synthesizing phenyl acetate and phenol were the same as in Example 1 except that the reaction temperature was 170°C and the contact time with the catalyst was 5.07 seconds. and the synthesis of phenyl acetate and phenol.

Further, in the same manner as in Example 1, the obtained solid catalyst was subjected to elemental analysis to determine the yields of the obtained phenyl acetate and phenol.

The obtained solid catalyst contains 0.35% by weight of Pd and Ga/
Pd (molar ratio) was 0.17, and K/Pd (molar ratio) was 2.2.

The results are shown in Table 1.

Comparative Example 1 [Catalyst Preparation] Ice i! II-acid approx. 200 [[11 and acetic anhydride approx. 50 m
0.4'3 g (2 mmol) of palladium #acid was dissolved at 60-70°C in the mixture with #1, and dried activated alumina (particle size of #8-#14 mesh) 30
g and stirred at 60-70°C for 4 hours. Then,
This solution was left at room temperature overnight and then heated to 80'C under reduced pressure.
The volatile components were distilled off to obtain a mixture.

Next, glacial acetic acid], 0.59 g of gallium acetate in OOml
(6 mmol) was added to the above mixture and stirred for 2 hours, then the volatile components were distilled off at 80°C under reduced pressure, and the resulting solid was heated to 180°C at 115°C.
Volatile components were removed under conditions of mm H (J).

Next, this solid was passed through a #42 mesh sieve to remove powder components, yielding 36.96 g of a solid catalyst.

The results of elemental analysis of the obtained solid catalyst were as follows.

Pd: 0.43% by weight, K: 0.47% by weight/Pd
(Molar ratio): 3.0 [Synthesis of phenyl acetate and phenol] Above catalyst 30
Phenyl acetate and phenol were synthesized in the same manner as in Example 1, except that ml (23.78 g) was used, and their yields were determined.

The results are shown in Table 1.

Sougosu [Preparation of catalyst] Ice i! i1-# about 200 fields and about 50 m of acetic anhydride! Add 0.45 g (2 mmol) of palladium acetate to the mixture with
Then, 30 g of dried activated alumina (particle size of #8 to #14 mesh) was added and stirred at 60 to 70 °C for 4 hours.Then, this solution was stirred at 60 to 70 °C for 4 hours. After standing overnight at room temperature, volatile components were distilled off at 60° C. under reduced pressure to obtain 345 g of solid catalyst.

The results of elemental analysis of the obtained solid catalyst were as follows.

Pd: 0.26 Weight j: 1; % [Synthesis of #acid phenyl and phenol] Above catalyst 30
ml (22, 20 g) and the contact time was 4.3 seconds, the same procedure as in Example 1 was carried out.
Acid phenyl and phenol were synthesized and their yields were determined.

The results are shown in Table 1.

Table 1 Gas reaction conditions, benzene/acetic acid/oxygen/nitrogen - 1/310.
46/1.84 (seventh heat), temperature 200°C2l 17
0°C *Palladium turnover frequency (Turn 0ver
Frequency): Conversion from benzene to phenyl acetate and phenol per Pd atom per hour ([f agent, patent attorney Shunichi Meiki

Claims (1)

[Scope of Claims] 1) An aromatic hydrocarbon, a carboxylic acid, and molecular oxygen are reacted in the presence of a catalyst in which a catalyst component containing a palladium component and a gallium component is supported on a carrier. A method for producing a carboxylic acid aryl ester. 2) The molar ratio of the palladium component and the gallium component constituting the catalyst based on the metal equivalent value is 100% of the palladium component.
Claim 1, characterized in that the gallium component is 0.1 to 5000 moles per mole, and the amount of the palladium component supported on the carrier is 0.001 to 10% by weight in terms of palladium metal. A method for producing a carboxylic acid aryl ester according to item 1. 3) A catalyst for producing aryl carboxylic acid esters, characterized in that a catalyst component containing a palladium component and a gallium component is supported on a carrier. 4) The molar ratio of the palladium component and the gallium component based on the metal equivalent value is 0.1 to 5000 mol of the gallium component to 100 mol of the palladium component, and the amount of the palladium component supported on the carrier is palladium 4. The catalyst for producing carboxylic acid aryl esters according to claim 3, wherein the content is 0.001 to 10% by weight in terms of metal.