JPWO2013081034A1 - Halogenated catalyst and method for producing the same - Google Patents

Abstract

  A halogenated catalyst for halogenating an aromatic ring, characterized in that iron oxide or zinc oxide is supported on a support composed of a composite oxide containing silicon and aluminum. At this time, the halogenation catalyst is preferably a bromination catalyst for brominating an aromatic ring. It is also preferable that 0.1-10 mmol of iron element or zinc element is contained with respect to 1 g of the composite oxide. It is also preferred that the composite oxide has a silicon atom to aluminum atom ratio (Si / Al) of 1 to 1000. This makes it possible to obtain a halogen compound in high yield.

Description

  The present invention relates to a halogenation catalyst for halogenating an aromatic ring and a method for producing the same. The present invention also relates to a method for producing a halogen compound using a halogenated catalyst.

  Conventionally, halogen compounds have become important intermediates or final products in the field of organic chemical industry, and many prior arts are known for their production methods. For example, a number of bromination reactions of benzene, the simplest aromatic compound, have been reported so far.

  Non-Patent Document 1 describes a method of synthesizing bromobenzene by reacting benzene and bromine in the presence of mercury oxide and sulfuric acid. However, in this method, it is necessary to add mercury oxide in a stoichiometric amount or more. In addition, this method has a problem that a neutralization step is required after the reaction because the reaction is performed under acidic conditions.

  Patent Document 1 describes a method of synthesizing bromobenzene by reacting benzene and bromine using sodium lauryl sulfate as a catalyst. However, this method has a problem that the reaction time is long and a neutralization step is required after the reaction because an aqueous sulfuric acid solution is used as a solvent.

  Non-Patent Document 2 describes a method of synthesizing 1,2,4,5-tetrabromobenzene by reacting benzene and bromine using aluminum bromide as a catalyst. Patent Document 2 describes a method of synthesizing 2-bromo-1,4-difluorobenzene by reacting 1,4-difluorobenzene and bromine using iron powder as a catalyst. However, since these catalysts are uniformly dissolved in the reaction solution, it is difficult to separate from the product after the reaction, and there is a problem that the catalyst cannot be reused.

  Non-Patent Document 3 describes a method of synthesizing bromobenzene by reacting benzene and bromine in the presence of zeolite. However, this synthesis method has a problem that an excessive amount of zeolite is required with respect to the amount of bromobenzene and bromine.

J. Org. Chem. 1988, 53, 1799-1800 Russian Journal of Organic Chemistry, 2008, 44 (9), 1323-1326 J. Chem. Soc., Perkin Trans. 1, 2000, 2745-2752

US2005 / 0137431 A1 JP-A-7-285896

  The present invention has been made to solve the above problems, and provides a halogenation catalyst for halogenating an aromatic ring, which can obtain a halogen compound in a high yield and can be easily recovered. It is intended. Moreover, it aims at providing the manufacturing method of such a halogenated catalyst. Furthermore, it aims at providing the method of manufacturing a halogen compound using such a halogenated catalyst.

  The above-mentioned problems are solved by providing a halogenation catalyst for halogenating an aromatic ring, wherein iron oxide or zinc oxide is supported on a support composed of a composite oxide containing silicon and aluminum. The At this time, the halogenation catalyst is preferably a bromination catalyst for brominating an aromatic ring. It is also preferable that 0.1-10 mmol of iron element or zinc element is contained with respect to 1 g of the composite oxide. It is also preferable that iron oxide is supported on the carrier made of the composite oxide.

  It is also preferred that the composite oxide has a silicon atom to aluminum atom ratio (Si / Al) of 1 to 1000. It is also preferable that the composite oxide is zeolite.

  Moreover, the said subject is a manufacturing method of the said halogenated catalyst, Comprising: The 1st process which mixes the complex oxide containing a silicon and aluminum, and an iron salt or a zinc salt in a solvent, and obtained by the said 1st process. A method for producing a halogenated catalyst, comprising: a second step of removing the solvent from the obtained mixture; and a third step of heating the mixture from which the solvent has been removed in the second step in an oxidizable atmosphere. It is also solved by providing.

  Furthermore, the subject is a method for producing a halogen compound using the halogenated catalyst; and a method for producing a halogen compound comprising reacting a compound having an aromatic ring with halogen in the presence of the halogenated catalyst. It is also solved by providing.

  According to the halogenation catalyst of the present invention, a halogen compound can be obtained in a high yield. In addition, the halogenated catalyst of the present invention is easily separated from the reaction system and easily recovered. According to the production method of the present invention, such a halogenated catalyst can be easily obtained. If the halogenated catalyst of the present invention is used, a halogen compound can be easily produced.

It is the figure which showed the analysis result by the powder X-ray-diffraction method of Na- (beta) zeolite and Na- (beta) zeolite which carry | supported iron oxide.

  The halogenation catalyst of the present invention is a catalyst for halogenating an aromatic ring, and iron oxide or zinc oxide is supported on a support made of a composite oxide containing silicon and aluminum. When the aromatic ring is halogenated using the halogenated catalyst of the present invention, the reaction system becomes a so-called heterogeneous system, and the catalyst can be easily separated and recovered from the reaction system.

  Here, the composite oxide used in the present invention contains at least silicon (Si), aluminum (Al), and oxygen (O). Specifically, it is a composite oxide containing a silicon oxide and an aluminum oxide, in which at least a part of silicon atoms and aluminum atoms are chemically bonded through oxygen.

  In the present invention, the ratio (Si / Al) of silicon atoms to aluminum atoms in the composite oxide is preferably 1 to 1000, more preferably 2 to 500, and 5 to 300. Further preferred. Specific examples of the complex oxide used in the present invention preferably include zeolite, silica alumina, and aluminosilicate, and more preferably zeolite.

  Further, it is preferable to contain 0.1 to 10 mmol of iron element or zinc element with respect to 1 g of the composite oxide. If the content of the iron element or zinc element relative to 1 g of the composite oxide is less than 0.1 mmol, the reactivity of the halogenation reaction may be lowered, more preferably 0.2 mmol or more, and even more preferably 0. .5 mmol or more. On the other hand, when the content of the iron element or zinc element with respect to 1 g of the composite oxide exceeds 10 mmol, the production cost may increase, more preferably 8 mmol or less, and further preferably 5 mmol or less. In the present invention, the iron element and the zinc element are supported in an oxide state on a support made of a composite oxide containing silicon and aluminum.

  From the viewpoint of obtaining a halogen compound in a high yield, it is preferable that iron oxide is supported on a support made of a composite oxide containing silicon and aluminum. At this time, the iron oxide supported on the carrier is preferably hematite.

  A preferred method for producing the halogenated catalyst of the present invention comprises a first step of mixing a composite oxide containing silicon and aluminum, an iron salt or a zinc salt in a solvent, and a mixture obtained in the first step. A second step of removing the solvent and a third step of heating the mixture from which the solvent has been removed in the second step in an oxidizable atmosphere.

  The iron salt or zinc salt used in the first step is not particularly limited as long as it is a metal salt that becomes an oxide when heated. Examples of the metal salts include iron chloride, iron nitrate, iron sulfate, iron acetate, iron acetylacetonate, zinc chloride, zinc nitrate, zinc sulfate, zinc acetate, zinc acetylacetonate, etc., which are inexpensive and easily available. Can do. The solvent used in the first step is not particularly limited as long as the metal salt is dissolved and can be easily distilled off, and examples thereof include polar organic solvents such as alcohol and water. Of these, alcohols having 3 or less carbon atoms, particularly methanol, are preferred. Moreover, the mixing operation in the first step is not particularly limited. The complex oxide may be added to and mixed with the metal salt solution, or the metal salt may be added and dissolved in a mixture of the complex oxide and the solvent.

  The method for removing the solvent in the second step is not particularly limited, and methods such as reduced pressure and heating can be employed.

  In the third step, the mixture from which the solvent has been removed is heated in an oxidizable atmosphere. The oxidizable atmosphere here means an atmosphere in which the metal salt contained in the mixture can be oxidized by heating. Therefore, the atmosphere for heating may be an atmosphere containing oxygen, and heating in the air is simple and preferable. The heating temperature is preferably 150 to 500 ° C. The heating time is set in relation to the heating temperature, but may be set as appropriate so that the metal salt contained in the mixture becomes an oxide. The heating method is not particularly limited, and examples thereof include a method of heating in an oven and a method of heating using a heater.

  Using the halogenated catalyst of the present invention, a halogen compound can be produced by reacting a compound having an aromatic ring with halogen. When the halogenated catalyst of the present invention is used, a hydrogen atom on the aromatic ring is substituted with a halogen atom by an aromatic electrophilic substitution reaction. And a halogen compound can be obtained with a sufficient yield.

  Here, the compound having an aromatic ring may be any compound as long as it has an aromatic ring and at least one atom bonded to the carbon atom of the aromatic ring is a hydrogen atom. Examples of the aromatic ring include a benzene ring, a naphthalene ring, an anthracene ring, and biphenyl. Further, it may be a 5-membered heteroaromatic ring such as a thiophene ring, a pyrrole ring or a furan ring, or a 6-membered heteroaromatic ring such as a pyridine ring or a pyrimidine ring. Moreover, the compound which these aromatic rings condensed may be sufficient. Examples of the substituent introduced into these aromatic rings include halogen, amino group, hydroxy group, alkoxy group, alkyl group, aryl group, cyano group, nitro group and the like. A plurality of such substituents may be introduced.

  The reaction temperature when producing the halogen compound is usually room temperature to 150 ° C., and the reaction time is appropriately set in relation to the reaction temperature. When the halogen compound is produced, the molar ratio of the starting compound having an aromatic ring and the halogen is not particularly limited. It may be equivalent, or one may be in excess. The amount of the halogenated catalyst is not particularly limited. The amount of the halogenated catalyst used per 1 mol of the raw material is preferably 0.5 mol or less, and more preferably 0.1 mol or less, as the number of mols of iron element or zinc element. Moreover, the usage-amount of the halogenated catalyst with respect to 1 mol of raw materials is 0.001 mol or more normally as a mol number of an iron element or a zinc element.

  In the present invention, the halogenation catalyst is preferably a bromination catalyst for brominating an aromatic ring. Examples of the halogen used in the halogenation reaction in the present invention include chlorine, bromine and iodine. Among these, when the halogenated catalyst of the present invention is used for bromination reaction, the reaction proceeds efficiently.

  A preferred embodiment of the present invention is to separate the halogenated catalyst from the reaction system after completion of the reaction. More preferably, the separated halogenated catalyst is reused. Since the halogenated catalyst of the present invention is a so-called heterogeneous catalyst, the halogenated catalyst can be separated by a simple method such as centrifugation or filtration after completion of the halogenation reaction. At this time, the halogenated catalyst separated from the reaction system is preferably reused after being heated. As the heating conditions, the same conditions as in the third step in the method for producing a halogenated catalyst are preferably employed. Thus, even when the halogenated catalyst of the present invention is separated and reused, a halogen compound can be obtained in high yield. Therefore, the halogenated catalyst of the present invention is excellent in terms of environment and cost.

  Hereinafter, the present invention will be described more specifically with reference to examples.

Example 1 (Examination of metal species supported on a carrier)
Example 1 is an example in which the reactivity of the halogenation reaction was examined when the metal species supported on the carrier was changed. Specifically, halogenation catalysts each having iron, zinc, manganese, copper, chromium, and cobalt supported on a carrier were prepared, and the reactivity of bromination reaction and chlorination reaction using these catalysts was examined. Further, the halogenated catalyst used in Reaction Example 1-1 was analyzed by a powder X-ray diffraction method.

[Preparation of halogenated catalyst]
Iron chloride as the metal salt (III) hexahydrate _{(FeCl 3 · 6H 2 O)} 0.27g (1mmol) was dissolved in methanol 10 ml. To the obtained solution, 1 g of zeolite was added as a carrier, and stirred at room temperature for 1 hour. Then, methanol was distilled off using an evaporator, and it heated at 300 degreeC in air | atmosphere for 1 hour using the electric furnace, and obtained the halogenated catalyst used for Reaction Example 1-1. Moreover, as shown in Table 1, in Reaction Example 1-2, 0.14 g (1 mmol) of zinc chloride (ZnCl ₂ ) was used as the metal salt, and in Reaction Example 1-3, manganese (II) chloride tetrahydrate as the metal salt. Product (MnCl ₂ .4H ₂ O) 0.20 g (1 mmol) was used, and in Reaction Example 1-4, 0.13 g (1 mmol) of copper (II) chloride (CuCl ₂ ) was used as the metal salt, and Reaction Example 1-5 In this example, 0.27 g (1 mmol) of chromium (III) chloride hexahydrate (CrCl ₃ .6H ₂ O) is used as the metal salt, and in reaction example 1-6, cobalt (II) chloride hexahydrate (CoCl) is used as the metal salt. _The halogenated catalyst was obtained using 0.24 g (1 mmol) of 2.6H ₂ O). As the zeolite, Na-β zeolite (Catalyst Society reference catalyst “JRC-Z-B25”, SiO ₂ / Al ₂ O ₃ = 25/1) was used.

[Analysis by powder X-ray diffraction method]
Using the X-ray diffractometer, the Na-β zeolite and the halogenated catalyst used in Reaction Example 1-1 were analyzed by a powder X-ray diffraction method using Cu-Kα rays. The result is shown in FIG. As shown in FIG. 1, in the halogenated catalyst used in Reaction Example 1-1, a peak derived from hematite was observed, and it was found that the halogenated catalyst contained hematite (Fe ₂ O ₃ ). As the X-ray diffractometer, RINT-2000 manufactured by Rigaku Corporation was used.

Reaction Examples 1-1 to 8 (bromination reaction)
Under an argon atmosphere (1 atm), the halogenated catalyst shown in Table 1 (0.01 g), benzene (1 mL) and bromine (0.08 g, 0.5 mmol) were added to a test tube using dichloromethane as a solvent. The mixture was heated and stirred for 1.5 hours. Thereafter, the reaction mixture was treated with an aqueous sodium thiosulfate solution, and organic substances were extracted with hexane. The organic phase was analyzed by gas chromatography to determine the yield of bromobenzene. The hematite used in Reaction Example 1-8 is iron oxide (III) manufactured by Wako Pure Chemical Industries, Ltd. The results are shown in Table 1. The reaction formula is as shown in the following formula (I).

  As shown in Table 1, when iron was used as the metal species supported on the zeolite carrier, the bromination reaction of benzene proceeded almost quantitatively (Reaction Example 1-1). Also, when zinc (reaction example 1-2) was used as the metal species to be supported on the zeolite carrier, bromobenzene could be obtained in high yield. On the other hand, when manganese (reaction example 1-3), copper (reaction example 1-4), chromium (reaction example 1-5), and cobalt (reaction example 1-6) are used as the metal species to be supported on the zeolite carrier. The yield was low. The yield was also low when zeolite was simply used as the catalyst for the benzene bromination reaction (Reaction Example 1-7). When simply using iron oxide (hematite) as a catalyst for the benzene bromination reaction, the bromination reaction hardly proceeded (Reaction Example 1-8).

Reaction Example 1-9 (bromination reaction)
Under an argon atmosphere (1 atm), the halogenated catalyst of Reaction Example 1-1 (0.05 g), benzene (6 mL) and bromine (3.2 g, 20 mmol) were added to a 50 mL eggplant flask, and the top of the eggplant flask was added. A balloon filled with argon was attached. After stirring with heating at 40 ° C. for 2 hours, the reaction mixture was treated with an aqueous sodium thiosulfate solution, and organic substances were extracted with hexane. The organic phase was analyzed by gas chromatography to determine the yield of bromobenzene. The yield of bromobenzene was 87%. The reaction formula is as shown in the following formula (II).

Reaction Example 1-10 (chlorination reaction)
The halogenated catalyst (0.01 g) of Reaction Example 1-1 and benzene (1 mL) were placed in a test tube, and the air in the test tube was replaced with chlorine and sealed to create a chlorine atmosphere (1 atm). At this time, the chlorine added to the test tube was 2 mmol. After stirring with heating at 40 ° C. for 1.5 hours, the reaction mixture was treated with an aqueous sodium thiosulfate solution, and organic substances were extracted with hexane. The organic phase was analyzed by gas chromatography to determine the yield of chlorobenzene. The yield of chlorobenzene was 77%. The reaction formula is as shown in the following formula (III).

Example 2 (Investigation of carrier)
Example 2 is an example in which the reactivity of the halogenation reaction when the carrier was changed was examined. Specifically, except that the support was changed as shown in Table 2, a halogenated catalyst was prepared in the same manner as when the halogenated catalyst of Reaction Example 1-1 was prepared, and the reactivity of the bromination reaction was examined. . Here, in Reaction Example 2-1, the halogenation catalyst of Reaction Example 1-1, that is, the halogenation catalyst in which iron oxide is supported on a zeolite carrier was used. The aluminosilicate used in Reaction Example 2-2 is “MCM-41” (SiO ₂ / Al ₂ O ₃ = 74/1), and the silica alumina used in Reaction Example 2-3 is the catalyst “JRC- SAL-3 ”(SiO ₂ / Al ₂ O ₃ = 87/13). In Reaction Example 2-4, a halogenated catalyst was prepared using aluminum oxide as a carrier that was not a complex oxide, and in Reaction Example 2-5, silicon dioxide was used as a carrier that was not a complex oxide. is there.

  Bromination of benzene was carried out using these halogenated catalysts. The method is the same as that of Reaction Example 1-1 of Example 1 except that the reaction time is 2 hours in the bromination reaction of Example 1. The results are shown in Table 2.

  As shown in Table 2, when zeolite was used as a carrier for supporting iron oxide, the bromination reaction of benzene proceeded quantitatively (Reaction Example 2-1). Even when aluminosilicate was used as the carrier, the bromination reaction of benzene proceeded quantitatively (Reaction Example 2-2). Furthermore, also when silica alumina was used as a carrier, the bromination reaction of benzene proceeded almost quantitatively (Reaction Example 2-3). On the other hand, the yield when aluminum oxide was used as a carrier was about 70% (Reaction Example 2-4), and bromination reaction hardly proceeded when silicon dioxide was used as a carrier (Reaction Example). 2-5).

Example 3 (Examination of reusability)
Example 3 is an example of examining whether or not the halogenated catalyst can be separated from the reaction system and reused.

  First, the bromination reaction of benzene was performed using the halogenation catalyst of Reaction Example 1-1, that is, the halogenation catalyst in which iron oxide was supported on a zeolite carrier. After the reaction, the reaction solution was filtered through a membrane filter to recover the halogenated catalyst, washed with a very small amount of hexane, and then heated in the atmosphere at 300 ° C. for 1 hour using an electric furnace. The halogenated catalyst thus recovered was reused in the next reaction. The reactivity of the bromination reaction when this operation was repeated was examined. The conditions for the bromination reaction are the same as those in Reaction Example 1-1 of Example 1 except that 3 mL of benzene and 0.24 g (1.5 mmol) of bromine were used and the reaction time was 2 hours. The results are shown in Table 3.

  As shown in Table 3, the bromination reaction proceeded even when used repeatedly 4 times to obtain bromobenzene, and the reaction proceeded quantitatively. This confirmed that the halogenated catalyst can be recovered from the reaction system and reused.

Example 4 (Examination of reaction substrate)
Example 4 is an example in which the reactivity of the bromination reaction when the reaction substrate was changed was examined. Specifically, bromination reaction was performed using the reaction substrate shown in Table 4 using the halogenation catalyst used in Reaction Example 1-1, that is, the halogenation catalyst in which iron oxide is supported on a zeolite carrier. The conditions for the bromination reaction are as shown in Table 4.

  As a result of bromination reaction of bromobenzene under the conditions shown in Table 4, bromobenzene was brominated in high yield to obtain p- and o-dibromobenzene (Reaction Example 4-1). Further, as a result of bromination reaction of fluorobenzene, p-bromination reaction proceeded with high yield and high selectivity (Reaction Example 4-2). When the bromination reaction of 1,4-dibromobenzene was carried out under the conditions shown in Table 4, the mono and dibromination reactions proceeded (Reaction Example 4-3). In general, bromination reactivity of fluorine-substituted benzene is known to be lower than that of bromine-substituted benzene. However, when bromination reaction is carried out using the halogenation catalyst of Reaction Example 1-1, fluorine substitution is performed. The reaction also proceeded with benzene, and the yield was not bad (Reaction Examples 4-4 and 4-5).

Claims (8)

  A halogenated catalyst for halogenating an aromatic ring, wherein iron oxide or zinc oxide is supported on a support composed of a composite oxide containing silicon and aluminum.   The halogenated catalyst according to claim 1, wherein the halogenated catalyst is a brominated catalyst for brominating an aromatic ring.   The halogenation catalyst according to claim 1 or 2, comprising 0.1 to 10 mmol of iron element or zinc element with respect to 1 g of the composite oxide.   The halogenated catalyst according to any one of claims 1 to 3, wherein iron oxide is supported on a carrier made of the composite oxide.   The halogenation catalyst according to any one of claims 1 to 4, wherein the composite oxide has a ratio of silicon atoms to aluminum atoms (Si / Al) of 1 to 1000.   The halogenated catalyst according to any one of claims 1 to 5, wherein the composite oxide is zeolite. It is a manufacturing method of the halogenated catalyst in any one of Claims 1-6,
A first step of mixing a composite oxide containing silicon and aluminum and an iron salt or zinc salt in a solvent;
A second step of removing the solvent from the mixture obtained in the first step;
And a third step of heating the mixture from which the solvent has been removed in the second step in an oxidizable atmosphere, and a method for producing a halogenated catalyst. A method for producing a halogen compound using the halogenated catalyst according to claim 1;
A method for producing a halogen compound, comprising reacting a compound having an aromatic ring with halogen in the presence of the halogenated catalyst.

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