Metal-based immobilized catalyst and method for producing carboxylic acids and / or carboxylic acid esters using the same

Abstract

To provide a method with which production of a carboxylic acid by using carbon dioxide or formic acid as a raw material can be conducted without using triphenylphosphine or by using a flow reaction.SOLUTION: A metal-based immobilized catalyst is characterized as including a site in which a metal complex is immobilized on an inorganic oxide via a linker and a ligand.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to a metal-based immobilized catalyst and a method for producing a carboxylic acid or carboxylic acid ester using the same. More specifically, it relates to a metal-based immobilized catalyst usable in reactions for synthesizing carboxylic acids or carboxylic acid esters and a method for producing a carboxylic acid or carboxylic acid ester using the same. [Background technology]

[0002] Carboxylic acids and carboxylic acid esters are compounds widely used as raw materials for various industrial products and everyday goods. In recent years, the development of technologies that utilize carbon dioxide as a C1 carbon raw material and convert it into useful chemicals has become important not only from the perspective of reducing environmental impact but also from the perspective of effectively utilizing underutilized resources, and the production of carboxylic acids and carboxylic acid esters using carbon dioxide as a raw material has also been reported. For example, the hydroxycarbonylation of alkenes using Rh complex catalysts has been reported, and it has been reported that various aliphatic carboxylic acids can be synthesized in high yield from CO2 / H2 and alkenes using this reaction (see Non-Patent Literature 1). In addition, it has been reported that the hydroxycarbonylation of alkenes proceeds efficiently in the presence of an Rh complex catalyst when formic acid, obtained by reacting carbon dioxide and hydrogen, is used as a carbonylating agent (see Non-Patent Literature 2). Generally, in the production of carboxylic acids from alkenes, technologies using CO2 / H2 mixed gas or CO / H2O mixed gas are being considered. However, using formic acid as a carbonylating agent does not require high pressure in the reaction conditions and does not use flammable gas H2 or flammable and toxic gas CO. Therefore, it is considered an industrially important reaction not only in terms of reducing environmental impact but also in terms of manufacturing process safety. In addition to Non-Patent Document 2, reactions for producing carboxylic acids and their salts from alkenes and formic acid or its salts, and reactions for producing carboxylic acid esters from alkenes and acetic acid, etc. have also been reported (see Patent Documents 1-3 and Non-Patent Document 3). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Unexamined Patent Application Publication No. 2016 - 132634 [Patent Document 2] International Publication No. 04 / 076397 [Patent Document 3] Japanese Unexamined Patent Application Publication No. 2016 - 113380 [Non - Patent Document] <​​​​​​​​​​​​​​​​​​​​​​​​Furthermore, the methods described in Patent Documents 1 and 2 and Non-Patent Documents 1 to 3 all involve the production of carboxylic acids and the like by batch reaction methods. Batch reaction methods are manufacturing techniques in which all raw materials are put into a reaction vessel and the product is removed after the reaction is complete, and this process is repeated. While this method allows for the synthesis of compounds with complex structures used in fine chemicals and pharmaceuticals, it requires a lot of energy and labor because the isolation and purification of intermediates are repeated at each stage, and also generates a large amount of waste. Therefore, when considering industrial-scale production, it presents a significant problem from an environmental perspective. In addition, results from small-scale production are often not reproducible when scaled up, leading to problems with reaction control and a prolonged period for considering scale-up to industrial scale. On the other hand, flow reaction methods are manufacturing techniques in which starting materials are continuously fed from one end of a reaction tube and the product is continuously obtained from the other end. Because they have advantages such as high productivity and ease of scale-up to industrial scale, they have recently attracted attention as a method to solve the shortcomings of batch reaction methods. Thus, conventional manufacturing methods have room for improvement, and there is a need for a method that can produce carboxylic acids from carbon dioxide or formic acid as raw materials without using triphenylphosphine, which requires careful handling, and furthermore, can be carried out by a flow reaction method.

[0006] This invention has been made in view of the above-mentioned circumstances, and aims to provide a method for producing carboxylic acids from carbon dioxide or formic acid as raw materials without using triphenylphosphine, and which can also be carried out using a flow reaction method. [Means for solving the problem]

[0007] The inventors of the present invention investigated a method for producing carboxylic acids from carbon dioxide or formic acid as raw materials without using triphenylphosphine and also allowing the use of a flow reaction method, and focused on the catalyst used in the reaction. They found that by using a metal-based immobilized catalyst that includes a site on which a metal complex is immobilized using a support having a linker and ligand on an inorganic oxide, it is possible to carry out a reaction step for carboxylic acids and / or carboxylic acid esters by a flow reaction method in which a raw material alkene and formic acid and / or formic acid ester, or hydrogen and carbon dioxide, are continuously supplied to the catalyst, and that by using this immobilized catalyst, it is possible to synthesize carboxylic acids and the like without using triphenylphosphine, leading to the present invention.

[0008] In other words, the present invention is a metal-based immobilized catalyst characterized by including a site on which a metal complex is immobilized using a support having a linker and a ligand on an inorganic oxide.

[0009] The linker is preferably an alkylene group, an arylene group, or a group formed by a combination thereof.

[0010] It is preferable that the linker is a methylene group, an ethylene group, a propylene group, a phenylene group, or a group formed by a combination thereof.

[0011] The above ligand preferably contains at least one atom selected from the group consisting of phosphorus, nitrogen, oxygen, and sulfur atoms.

[0012] It is preferable that the inorganic oxide is an oxide of silicon, aluminum, titanium, or zirconium, or a composite oxide containing two or more of these.

[0013] The above metal complex preferably contains at least one atom selected from the group consisting of atoms from groups 8 to 12 of the periodic table and Cr.

[0014] Preferably, in the above metal-supported catalyst, the number of moles of metal atoms contained in the supported metal complex is 5 to 250 millimoles per 100 g of the weight of the support.

[0015] The present invention also provides the following formula (1); L 2 , 2 , 2 , 3 , 1 , 1 , 1 MX m (1) (In the formula, L represents a ligand containing atoms of Groups 14 to 16 of the periodic table, which may be the same or different. l and m represent the number of ligands, each being a number from 0 to 8. M represents a metal atom. X represents a halogen atom, a hydrogen atom, an alkyl group, or a hydroxyl group.) The method for producing a metal-supported catalyst is characterized by including a step of reacting a metal complex represented by the formula with a support having a linker and a ligand to immobilize the metal complex.

[0016] The present invention also provides the following formula (2);

[0017]

Chemical formula

[0018] (In the formula, R 1 , R 2 represent, independently of each other, a hydrogen atom or an organic group having 1 to 24 carbon atoms, and R 1 and R 2 may be linked together.) From an alkene represented by the formula, the following formula (3);

[0019]

Chemical formula

[0020] (In the formula, R 1 , R 2 are the same as those in formula (1). R 3) represents a hydrogen atom or an organic group having 1 to 24 carbon atoms. A method for producing a carboxylic acid and / or carboxylic acid ester represented by formula (2), the method comprising the step of reacting an alkene represented by formula (2) with formic acid and / or a formic acid ester, or reacting an alkene represented by formula (2) with hydrogen and carbon dioxide, in the presence of the metal-based immobilized catalyst of the present invention.

[0021] In the method for producing the above-mentioned carboxylic acid and / or carboxylic acid ester, it is preferable to carry out the reaction step using a flow reaction method with a fixed-bed flow reactor. [Effects of the Invention]

[0022] The metal-based immobilized catalyst of the present invention is a catalyst that enables the reaction of alkenes with formic acid and / or formic acid esters to synthesize carboxylic acids and / or carboxylic acid esters by a flow reaction method, without the use of triphenylphosphine, which requires careful handling. Therefore, it can be suitably used for the efficient production of various carboxylic acids and / or carboxylic acid esters. [Modes for carrying out the invention]

[0023] The present invention will be described in detail below. Furthermore, combinations of two or more of the individual preferred embodiments of the present invention described below are also preferred embodiments of the present invention.

[0024] 1. Metal-based immobilized catalyst The metal-based immobilized catalyst of the present invention includes a site on which a metal complex is immobilized using a support (also called an immobilized support) having a linker and ligand on an inorganic oxide. Because the catalyst is immobilized on a support, the catalyst can be easily separated after the reaction when using a batch reaction method. Furthermore, a flow reaction method can be used, where the reaction material is passed through the catalyst, allowing for the efficient production of carboxylic acids and / or carboxylic acid esters. The metal-based immobilized catalyst of the present invention may include a portion in which the metal complex is directly immobilized on an inorganic oxide, as long as it includes a portion in which the metal complex is immobilized using a support having a linker and a ligand on an inorganic oxide. In this invention, "metal" includes "precious metals."

[0025] In the metal-based immobilized catalyst of the present invention, the sites on which metal complexes are immobilized using a support having a linker and ligands on an inorganic oxide may have one bond with the support per metal complex, or may have multiple bonds with the support. Furthermore, the shape of the inorganic oxide constituting the support may be planar or three-dimensional. If it has a three-dimensional shape, it may have a porous structure.

[0026] The inorganic oxides mentioned above are not particularly limited as long as they can form a bond with the linker, and include oxides of silicon, aluminum, titanium, and zirconium, or composite oxides containing two or more of these. More specifically, examples include oxides of silica, diatomaceous earth, alumina, titania, zirconia, etc., composite oxides such as silica-alumina and silica-titania, crystalline metallosilicates having crystalline structures such as LTA, CHA, FER, MFI, MOR, FAU, BEA, and MTW, mesoporous materials, clay minerals, etc. Among these, silica, alumina, zirconia, silica-alumina, crystalline aluminosilicate, and mesoporous silica are preferred. More preferably, silica, alumina, silica-alumina, crystalline aluminosilicate having an MFI, MOR, FAU, or BEA structure, or mesoporous silica; even more preferably, silica, silica-alumina, crystalline aluminosilicate having an MFI, FAU, or MOR structure, or mesoporous silica; and most preferably, silica, silica-alumina, crystalline aluminosilicate having an MFI structure, or mesoporous silica.

[0027] The linker described above is a site that connects the inorganic oxide and the ligand, and only needs to have a site that bonds to the inorganic oxide and a site that bonds to the ligand. The bond may be a chemical bond or a physical bond. The linker is preferably a divalent hydrocarbon group. When the linker is a divalent hydrocarbon group, it is preferable that it is a hydrocarbon group having 2 or more carbon atoms. More preferably, it is a hydrocarbon group having 2 to 20 carbon atoms, and even more preferably, a hydrocarbon group having 2 to 10 carbon atoms. The divalent hydrocarbon group is preferably an alkylene group, an arylene group, or a group formed by combining these. More preferably, it is a methylene group, an ethylene group, a propylene group, a butylene group, a phenylene group, or a group formed by combining these.

[0028] The ligand described above is not particularly limited as long as it can bind to the linker and coordinate to the metal complex, but it is preferable that it contains at least one atom selected from the group consisting of phosphorus, nitrogen, oxygen, and sulfur atoms. Including such an atom allows for more sufficient immobilization of the metal complex on the support, more sufficiently suppresses the elution of the catalyst into the reaction solution, and extends the catalyst lifetime. More preferably, it contains phosphorus and nitrogen atoms, and even more preferably, phosphorus atoms. Ligands containing phosphorus atoms also act as reaction accelerators for the reaction of the alkene represented by formula (2) with formic acid and / or formic acid esters, or for the reaction of the alkene represented by formula (2) with hydrogen and carbon dioxide. In the metal-based immobilized catalyst of the present invention, the ligand is stabilized against air oxidation because it is immobilized on the support, and its effect as a reaction accelerator is less likely to be lost. Therefore, if the ligand contains a phosphorus atom, the selectivity of the carboxylic acid or carboxylic acid ester can be improved.

[0029] The ligands mentioned above are given by the following equation (4); *-YZ n (4) (In the formula, Y represents one of a phosphorus atom, a nitrogen atom, an oxygen atom, or a sulfur atom. Z represents a hydrogen atom or a monovalent organic group having 1 to 30 carbon atoms, and organic groups may bond with each other to form a divalent group. n is a number of 1 or 2. *- represents the bonding site with the linker.) is preferred. The monovalent organic group represented by Z in formula (4) preferably has 1 to 25 carbon atoms. More preferably, it has 1 to 20 carbon atoms. A specific example of a monovalent organic group represented by Z in equation (4) is R in equation (2), which will be discussed later. 1 , R 2 It is similar to a monovalent organic group.

[0030] Furthermore, as long as the metal-based immobilized catalyst of the present invention includes a region where a metal complex is immobilized on an inorganic oxide via a linker and ligand, it may also include a region where a halogen atom is bonded to the end of a linker bonded to an inorganic oxide, a region where a ligand is bonded to the end of a linker bonded to an inorganic oxide (a region where only a ligand is bonded), or a region where a halogen atom is directly bonded (immobilized) to an inorganic oxide. Since ligands containing halogen atoms or phosphorus atoms function as reaction accelerators in the reaction to produce carboxylic acids using carbon dioxide or formic acid as a raw material, if the metal-based immobilized catalyst has, in addition to a region where a metal complex is immobilized on an inorganic oxide via a linker and ligand, a region where a halogen atom is immobilized directly on the inorganic oxide or via a linker, or a region where a ligand containing a phosphorus atom is bonded to the end of a linker bonded to an inorganic oxide, it is expected that the same effect as when a reaction accelerator is used can be obtained without adding a reaction accelerator separately to the catalyst of the present invention. Examples of linkers in the region where a halogen atom is bonded to the end of a linker bonded to an inorganic oxide include those similar to those described above. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine, with iodine being preferred in terms of its function as a reaction accelerator.

[0031] In the metal-based immobilized catalyst of the present invention, the ratio (molar ratio) of the portion where a halogen atom is bonded to the end of a linker bonded to an inorganic oxide, or where a halogen atom is directly bonded (immobilized) to an inorganic oxide, or where a ligand containing a phosphorus atom is bonded to the end of a linker bonded to an inorganic oxide, to the portion where a metal complex is immobilized on the inorganic oxide via a linker and ligand is not particularly limited. However, the ratio (portion where a halogen atom is bonded (immobilized) to an inorganic oxide via a linker or directly + portion where a ligand containing a phosphorus atom is bonded to the end of a linker bonded to an inorganic oxide) / portion where a metal complex is immobilized on the inorganic oxide via a linker and ligand) is preferably 30 or less. More preferably, it is 20 or less, and even more preferably 10 or less.

[0032] The metal complex is not particularly limited in terms of the metal atoms it contains, as long as it functions as a catalyst for the reaction to produce a carboxylic acid and / or carboxylic acid ester represented by formula (3) from an alkene represented by formula (2). However, it is preferable that the metal atoms are at least one atom selected from the group consisting of atoms from groups 8 to 12 of the periodic table and Cr. Including such metal atoms allows the complex to function more effectively as a catalyst for the above reaction. More preferably, the atoms are from groups 8 to 10 of the periodic table, even more preferably from group 9 of the periodic table, and most preferably Rh and Ir.

[0033] The number of ligands (ligands other than those bonded to the linker) in the above metal complex varies depending on the type of metal atom in the complex, but it is preferably between 0 and 8. Ligands other than those bonded to the linker are preferably ligands containing atoms from groups 14 to 16 of the periodic table. More preferably, they contain at least one atom selected from the group consisting of carbon atoms, nitrogen atoms, phosphorus atoms, arsenic atoms, oxygen atoms, and sulfur atoms, even more preferably carbon atoms, nitrogen atoms, phosphorus atoms, oxygen atoms, and sulfur atoms, and most preferably carbon atoms, phosphorus atoms, and oxygen atoms. These ligands containing atoms from groups 14 to 16 of the periodic table may be monodentate ligands, bidentate ligands, or multidentate ligands with two or more dentates, depending on the number of coordination sites, preferably monodentate ligands and bidentate ligands, and more preferably monodentate ligands.

[0034] To give more detailed examples of ligands containing atoms from groups 14 to 16 of the periodic table, it is preferable that the ligand is selected from carbon monoxide, carboxylic acids, acetylacetone, alkene compounds, amine compounds, imine compounds, phosphine compounds, N-heterocyclic carbene compounds, nitrile compounds, and isocyanide compounds. Examples of carboxylic acids include formic acid, acetic acid, and propionic acid, which have 1 to 30 carbon atoms. Examples of alkene compounds include alkenes with 2 to 30 carbon atoms, such as ethylene, propylene, and cyclooctene; and alkadienes with 4 to 30 carbon atoms, such as butadiene, cyclopentadiene, and 1,5-cyclooctadiene. Examples of amine compounds include ammonia; (mono, di, tri)alkylamines with 1 to 30 carbon atoms, such as methylamine, dimethylamine, and trimethylamine; (mono, di, tri)arylamines with 1 to 30 carbon atoms, such as phenylamine, diphenylamine, and triphenylamine; and diamines with 1 to 10 carbon atoms, such as ethylenediamine, propylenediamine, and butane-1,4-diamine. Examples of imine compounds include pyridine; diimines such as 2,2'-bipyridine, 1,10-phenanthroline, and 1,8-naphthyridine. Examples of phosphine compounds include trialkylphosphines with 1 to 24 carbon atoms, such as trimethylphosphine; triarylphosphines with 1 to 24 carbon atoms, such as triphenylphosphine; and diphosphines such as 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, and 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl. Examples of N-heterocyclic carbene compounds include 1,3-di-tert-butylimidazole-2-ylidene, 1,3-bis(2,6-diisopropylphenyl)imidazole-2-ylidene, 1,3-dimethylimidazole-2-ylidene, and 1,3-bis(2,6-diisopropylphenyl)imidazolidine-2-ylidene, which are N-heterocyclic carbene compounds with 3 to 30 carbon atoms derived from imidazolium salts. Examples of nitrile compounds include alkanes, alkenes, and alkynes with 1 to 24 carbon atoms, as well as aromatic hydrocarbons such as benzene and naphthalene, in which hydrogen atoms are replaced with -CN. Examples of isocyanide compounds include alkanes, alkenes, and alkynes with 1 to 24 carbon atoms, as well as aromatic hydrocarbons such as benzene and naphthalene, in which hydrogen atoms are replaced with -NC atoms.

[0035] In the present invention, the metal-based immobilized catalyst preferably contains 5 to 250 millimoles of metal atoms per 100 g of support. Containing metal atoms in this proportion allows the metal-based immobilized catalyst of the present invention to exhibit its catalytic function more fully. More preferably, the number of metal atoms in the immobilized metal complex per 100 g of support is 10 to 200 millimoles, and even more preferably, 15 to 150 millimoles.

[0036] In the metal-based immobilized catalyst of the present invention, it is preferable that the number of moles of metal atoms contained in the immobilized metal complex is 0.04 to 2.0 moles per mole of ligand bonded to the linker represented by Y in formula (4) above. When metal atoms are contained in such a ratio, the metal-based immobilized catalyst of the present invention exhibits its catalytic function more fully. More preferably, it is 0.08 to 1.7 moles, even more preferably 0.08 to 1.7 moles, and 0.1 to 1.5 moles.

[0037] 2. Method for producing metal-based immobilized catalysts As long as the metal-based immobilized catalyst of the present invention can be obtained, the method for producing the metal-based immobilized catalyst is not particularly limited, but the following formula (1); L l MX m (1) A preferred manufacturing method includes the step of reacting a metal complex represented by the formula (wherein L represents a ligand containing atoms from groups 14 to 16 of the periodic table, either identical or different; l and m represent the number of ligands, each number from 0 to 8; M represents a metal atom; and X represents a halogen atom, hydrogen atom, alkyl group, or hydroxyl group) with a support having a linker and ligands to immobilize it.

[0038] The specific examples of L in formula (1) above are the same as the specific examples of metal complexes having these ligands as described above. Ligand L may also be a monodentate ligand, a bidentate ligand, or a polydentate ligand with two or more dentates, depending on the number of coordination sites. Examples of halogen atoms for X in formula (1) above include fluorine, chlorine, bromine, and iodine. Examples of alkyl groups for X in formula (1) above include alkyl groups having 1 to 30 carbon atoms, such as methyl, ethyl, propyl, and cyclohexyl groups.

[0039] The method for immobilizing the above-mentioned metal complex by reacting it with a support having a linker and ligand is not particularly limited. For example, a method in which the metal complex and the support having a linker and ligand are reacted by stirring in a solvent can be used. In this case, the solid metal complex and the solid support having a linker and ligand may be added to the solvent and stirred, or the metal complex and the support having a linker and ligand may be mixed separately with the solvent beforehand to form a solution (or suspension), and these solutions (or suspensions) may be mixed and stirred together. When mixing the solutions (or suspensions), the entire amount may be added and mixed at once, or they may be added sequentially, but it is preferable to add the metal complex solution (or suspension) sequentially to the solution (or suspension) of the support having a linker and ligand and mix.

[0040] The support having a linker and ligand used in the above reaction preferably has a ratio of 0.01 to 15 moles of atoms coordinating to the metal complex in the ligand per 100 g of support. Using such a support makes it possible to obtain an immobilized catalyst with a sufficient amount of metal complex bound to the support, and also more effectively suppresses the elution of the catalyst into the reaction solution, thereby extending the catalyst lifetime. More preferably, the support has a ratio of 0.02 to 10 moles of atoms coordinating to the metal complex in the ligand per 100 g of support, and even more preferably, the ratio of atoms coordinating to the metal complex is 0.03 to 5 moles.

[0041] The amount of metal complex used in the above reaction is preferably 5 to 250 millimoles of metal atoms contained in the immobilized metal complex per 100 g of support having a linker and ligand, considering both the immobilization of a sufficient amount of metal complex on the support and the reaction yield. More preferably, it is 10 to 200 millimoles per 100 g of support, and even more preferably, 15 to 150 millimoles.

[0042] Furthermore, considering the need to immobilize a sufficient amount of the metal complex on the support and the yield of the reaction, the amount of metal complex used in the above reaction is preferably such that the ratio of the number of moles of metal atoms in the metal complex to the number of moles of atoms in the support that coordinate to the metal complex (number of moles of metal atoms in the metal complex / number of moles of atoms that coordinate to the metal complex) is 0.04 to 2.0. More preferably, the ratio of moles is 0.08 to 1.7, and even more preferably, the ratio of moles is 0.1 to 1.5.

[0043] When the above metal complex reacts with a support having a linker and ligand using a solvent, the solvent used is not particularly limited as long as the reaction proceeds, but for example, water; alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol; aromatic or aliphatic hydrocarbons such as benzene, toluene, xylene, cyclopentane, cyclohexane, pentane, n-hexane; ester compounds such as ethyl acetate; ketone compounds such as acetone, methyl ethyl ketone; cyclic ether compounds such as tetrahydrofuran, dioxane; diethyl ether, dibutyl ether, diisopropyl ether Examples include chain ether compounds such as ether; halogenated hydrocarbons such as dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, 1,2-dichloroethylene, trichloroethylene, and tetrachloroethylene; sulfoxides such as dimethyl sulfoxide; amides such as N,N-dimethylformamide and N-methylpyrrolidone; ureas such as tetramethylurea and N,N'-dimethylimidazolidinone; acetic acid, propionic acid, acetonitrile, etc., and one or more of these can be used.

[0044] The reaction temperature in the step of immobilizing the metal complex represented by formula (1) above by reacting it with a support having a linker and ligand is not particularly limited as long as the reaction proceeds, and is usually carried out below the boiling point of the solvent used. The reaction temperature is preferably 5 to 200°C. By carrying out the reaction at such a temperature, the yield of the immobilized catalyst obtained can be increased. More preferably, it is 10 to 180°C, and even more preferably, 15 to 150°C. In order to prevent loss due to solvent volatilization, when carrying out the reaction near the boiling point of the solvent, the container may be sealed and the reaction may be carried out, or a reflux condenser may be provided and the reaction may be carried out under reflux conditions. Furthermore, the reaction pressure is not particularly limited as long as the reaction proceeds, but it is preferably 0 to 10 MPa. More preferably, it is 0 to 5 MPa, and even more preferably, 0.1 to 1 MPa. Furthermore, considering the yield of the immobilized catalyst obtained and the efficiency of the immobilized catalyst production, the reaction time is preferably 0.5 to 100 hours. More preferably, it is 0.5 to 72 hours, even more preferably, 0.5 to 48 hours, and most preferably, 0.5 to 24 hours.

[0045] The present invention's method for producing a metal-based immobilized catalyst may include steps other than the step of reacting the metal complex represented by formula (1) with a support having a linker and a ligand to immobilize it. Other steps include the step of obtaining a support having a linker and a ligand, the step of separating the immobilized catalyst obtained from the reaction solution, the step of washing the immobilized catalyst after separation, the step of drying the immobilized catalyst, and the step of activating the immobilized catalyst by treatment such as oxidation or reduction.

[0046] The method for obtaining the support having the linker and ligand is not particularly limited as long as a support having the linker and ligand can be obtained. For example, a method can be used that includes the steps of reacting an inorganic oxide, which is a support, with a compound that will become a linker to obtain a support to which the linker is bonded, and reacting the support to which the linker is bonded with a compound that will become a ligand to bond the ligand to the linker.

[0047] A method for producing a metal-based immobilized catalyst includes the steps of: reacting an inorganic oxide, which is a support, with a compound that will serve as a linker to obtain a support to which a linker is bonded; reacting a compound that will serve as a ligand with the support to which the linker is bonded to obtain a ligand to the linker; and reacting a metal complex with the support having the linker and ligand to immobilize it. By adjusting the amounts of the compound that will serve as the linker, the compound that will serve as the ligand, and the metal complex used, it is possible to produce metal-based immobilized catalysts having a site where a halogen atom is bonded to the end of the linker bonded to the inorganic oxide, or having a site where a ligand containing a phosphorus atom is bonded to the end of the linker bonded to the inorganic oxide, and the amounts of these sites can be adjusted. When manufacturing a metal-based immobilized catalyst that includes a site where halogen atoms are directly bonded (immobilized) to the inorganic oxide as described above, it is sufficient to perform a step in which halogen atoms are directly bonded (immobilized) to the inorganic oxide.

[0048] The method for separating the immobilized catalyst obtained from the liquid after the above reaction is not particularly limited, and methods such as centrifugation and filtration can be used.

[0049] The solvent used in the step of washing the immobilized catalyst after the above separation is not particularly limited as long as it can wash the immobilized catalyst, and the solvents exemplified in the reaction step of the metal complex with the support having a linker and ligand described above can be used. Considering the effectiveness of washing and the ease of solvent removal in the drying step, for example, one or more of the following can be used: ethyl alcohol, diethyl ether, pentane, cyclopentane, tetrahydrofuran, hexane, ethyl acetate, cyclohexane, acetonitrile, toluenebenzene, etc.

[0050] The drying temperature in the drying process of the immobilized catalyst described above is not particularly limited, but can be, for example, 20 to 300°C. Preferably, it is 20 to 200°C, more preferably 20 to 150°C, and even more preferably 20 to 120°C. The drying process can be carried out under atmospheric pressure or reduced pressure. Reduced pressure is preferable because it can lower the boiling point of the solvent, allowing drying to be performed at a lower temperature. The drying time is also not particularly limited, but can be, for example, 0.5 to 24 hours.

[0051] 3. Method for producing carboxylic acids and / or carboxylic acid esters The present invention also relates to the following formula (2);

[0052] [ka]

[0053] (In the formula, R 1 , R 2 R represents a hydrogen atom or an organic group having 1 to 24 carbon atoms, either identical or different. 1 and R 2 The two may be linked. From an alkene represented by (3), the following equation is derived:

[0054] [ka]

[0055] (In the formula, R 1 , R 2 This is the same as equation (1). R 3 (wherein represents a hydrogen atom or an organic group having 1 to 24 carbon atoms.) A method for producing carboxylic acids and / or carboxylic acid esters represented by formula (2), the method for producing carboxylic acids and / or carboxylic acid esters also includes the step of reacting an alkene represented by formula (2) with formic acid and / or a formic acid ester, or reacting hydrogen with carbon dioxide, in the presence of the metal-based immobilized catalyst of the present invention. As described above, by using the metal-based immobilized catalyst of the present invention, it is possible to react the above-mentioned alkene with formic acid and / or formic acid ester without using triphenylphosphine, which requires careful handling, or to produce carboxylic acids and / or carboxylic acid esters by reacting the above-mentioned alkene with hydrogen and carbon dioxide, as described later. Furthermore, unlike conventional catalysts, the catalyst of the present invention is immobilized on a support, so when a batch reaction method is used, separation of the reaction product and the catalyst after the reaction is easy, and purification costs can be reduced. In addition, carboxylic acids and / or carboxylic acid esters can also be produced using a flow reaction method.

[0056] In equation (2) above, R 1 , R 2 R represents a hydrogen atom or an organic group having 1 to 24 carbon atoms, either identical or different. 1 and R 2 They may be connected. R 1 , R 2 If the organic group is monovalent, the number of carbon atoms in the organic group is preferably 1 to 20. More preferably, it is 1 to 16. R 1 , R 2When is a monovalent organic group, examples of organic groups include alkyl groups, alkenyl groups, alkoxy groups, aryl groups, arylalkyl groups, aryloxy groups, aryloxycarbonyl groups, acyl groups, alloyl groups, alkylsulfonyl groups, arylsulfonyl groups, arylalkylsulfonyl groups, trialkylsilyl groups, dialkylarylsilyl groups, alkyldiarylsilyl groups, triarylsilyl groups, bis(dialkylamino)phosphinoyl groups, dialkylphosphinoyl groups, diarylphosphinoyl groups, dialkylphosphonyl groups, and diarylphosphonyl groups. Among these, alkyl groups, alkenyl groups, alkoxycarbonyl groups, aryloxycarbonyl groups, acyl groups, alloyl groups, alkylsulfonyl groups, arylsulfonyl groups, arylalkylsulfonyl groups, bis(dialkylamino)phosphinoyl groups, dialkylphosphinoyl groups, diarylphosphinoyl groups, dialkylphosphonyl groups, and diarylphosphonyl groups are preferred.

[0057] The above R 1 , R 2 The organic groups listed as specific examples may all have one or more hydrogen atoms substituted with substituents. Examples of substituents include alkyl groups, aryl groups, alkenyl groups, alkoxy groups, aryloxy groups, alkoxycarbonyl groups, aryloxycarbonyl groups, acyl groups, aroyl groups, alkylsulfonyl groups, arylsulfonyl groups, arylalkylsulfonyl groups, trialkylsilyl groups, dialkylarylsilyl groups, triarylsilyl groups, bis(dialkylamino)phosphinoyl groups, dialkylphosphinoyl groups, diarylphosphinoyl groups, dialkylphosphonyl groups, diarylphosphonyl groups, carboxyl groups, sulfonyl groups, amino groups, silyl groups, chloro groups, fluoro groups, trifluoromethyl groups, 4-pyridyl groups, 3-pyridyl groups, and 2-pyridyl groups. The number of carbon atoms in the substituent is not particularly limited; the total number of carbon atoms in the organic group, including the substituent, should be between 1 and 24, but it is preferable that the number of carbon atoms be between 0 and 23.

[0058] R in equation (3) above3 This is a hydrogen atom or an organic group having 1 to 24 carbon atoms, but the organic group preferably has 1 to 20 carbon atoms. More preferably, it has 1 to 16 carbon atoms. R 3 A specific example of the organic group is R 1 , R 2 Similar to the specific examples of organic groups, one or more hydrogen atoms of the organic group may be substituted with substituents, and specific examples of substituents are also R 1 , R 2 It is similar to that.

[0059] As described above, the present invention's method for producing carboxylic acids and / or carboxylic acid esters uses a catalyst immobilized on a support, allowing for the use of a flow reaction method in addition to the batch reaction method used with conventional catalysts. By using the flow reaction method, it is possible to produce with high productivity, while saving energy, space, and reducing waste. Furthermore, since the production volume can be controlled by operating time in the flow reaction method, it is possible to handle both small-scale and large-scale production with the same equipment, allowing for a more compact manufacturing facility. This reduces the reaction space, thus minimizing the damage from accidents, even when using highly hazardous substances, making it a safer method. Moreover, significant scaling up of production can be easily achieved by increasing the size and numbering of the reaction tubes. In the flow reaction method, a reactor can be arbitrarily selected from, for example, a fixed-bed flow reactor, a fluidized-bed flow reactor, a moving-bed flow reactor, etc. One preferred embodiment of the present invention is to carry out the step of reacting the alkene represented by formula (2) with formic acid and / or formic acid ester using a flow reaction method with a fixed-bed flow reactor.

[0060] When the step of reacting the alkene represented by formula (2) with formic acid and / or formic ester is carried out by a flow reaction method, the molar ratio of the alkene represented by formula (2) to the formic acid and / or formic ester supplied to the catalyst is preferably 0.1 to 20 moles of formic acid and / or formic ester per mole of alkene. More preferably, the ratio is 0.5 to 10 moles of formic acid and / or formic ester per mole of alkene, and even more preferably, the ratio is 1.0 to 5 moles of formic acid and / or formic ester per mole of alkene.

[0061] When the reaction of the alkene represented by formula (2) with formic acid and / or formic ester is carried out by a flow reaction method, the flow rate of the reaction material containing the alkene represented by formula (2) and formic acid and / or formic ester supplied to the catalyst, when expressed in liquid-space velocity (LHSV), is 0.1 to 100 h, considering the amount produced, production efficiency, and product yield. -1 Preferably, 0.1 to 50 hours. -1 And more preferably, 0.1 to 40 hours -1 That is the case.

[0062] When the step of reacting the alkene represented by formula (2) with formic acid and / or formic acid ester is carried out by a flow reaction method, the reaction temperature is not particularly limited as long as the reaction proceeds, but it is preferably 100 to 250°C. By carrying out the reaction at such a temperature, the yield of the resulting carboxylic acid can be increased. More preferably, it is 140 to 220°C, and even more preferably 160 to 200°C. Furthermore, the reaction pressure is not particularly limited as long as the reaction proceeds, but it is preferably 0.1 to 50 MPa. More preferably 0.1 to 30 MPa, even more preferably 0.5 to 20 MPa, and most preferably 1.0 to 20 MPa.

[0063] When the step of reacting the alkene represented by formula (2) with formic acid and / or formic acid ester is carried out by a batch reaction method, considering the need to allow the reaction to proceed sufficiently and the cost of production, the amount of catalyst used is preferably such that the number of moles of metal atoms contained in the catalyst is 0.01 to 1.0 moles per mole of the alkene represented by formula (2). More preferably, the ratio is 0.02 to 1.0 moles, and even more preferably, the ratio is 0.04 to 1.0 moles.

[0064] When the step of reacting the alkene represented by formula (2) with formic acid and / or formic acid ester is carried out by a batch reaction method, the amount of formic acid and / or formic acid ester used is preferably 0.1 to 20 moles per mole of the alkene represented by formula (2). More preferably, it is 0.5 to 10 moles per mole of the alkene represented by formula (1), and even more preferably, it is 1.0 to 5 moles.

[0065] When the step of reacting the alkene represented by formula (2) with formic acid and / or formic acid ester is carried out by a batch reaction method, the reaction temperature is not particularly limited as long as the reaction proceeds, but it is preferably 100 to 250°C. Carrying out the reaction at such a temperature can increase the yield of the resulting carboxylic acid. More preferably, it is 140 to 220°C, and even more preferably, 160 to 200°C. Furthermore, the reaction pressure is not particularly limited as long as the reaction proceeds, but it is preferably 0.1 to 50 MPa. More preferably 0.1 to 30 MPa, even more preferably 0.5 to 20 MPa, and most preferably 1.0 to 20 MPa. Furthermore, considering the yield of carboxylic acids and / or carboxylic acid esters and the efficiency of production of carboxylic acids and / or carboxylic acid esters, the reaction time is preferably 0.5 to 24 hours. More preferably, it is 0.5 to 20 hours, and even more preferably, 0.5 to 10 hours.

[0066] In the method for producing carboxylic acids and / or carboxylic acid esters of the present invention, the step of reacting the alkene represented by formula (2) with formic acid and / or a formic acid ester in the presence of the metal-based immobilized catalyst of the present invention may be carried out using a reaction accelerator. Reaction accelerators include halogenated aliphatic hydrocarbons such as methyl chloride, methyl bromide, methyl iodide, ethyl chloride, ethyl bromide, ethyl iodide, propyl chloride, propyl bromide, propyl iodide butyl chloride, butyl bromide, butyl iodide, 1-chloro-3,5-dimethylcyclohexane, 1-bromo-3,5-dimethylcyclohexane, and 1-iodo-3,5-dimethylcyclohexane; methyltriphenylphosphonium chloride, methyltriphenylphosphonium bromide, methyltriphenylphosphonium iodide, ethyltriphenylphosphonium chloride, ethyltriphenylphosphonium bromide, ethyltriphenylphosphonium iodide, chloromethyl-triphenylphosphonium chloride, bromomethyl-triphenylphosphonium bromide, iodomethyl-triphenylphosphonium iodide, cyclohexyltriphenylphosphonium chloride, cyclohexyltriphenylphosphonium bromide, and cyclo Phosphonium salts such as lohexyltriphenylphosphonium iodide, triphenylphosphine hydrochloride, triphenylphosphine hydrobromide, and triphenylphosphine hydroiodide; ammonium salts such as tetramethylammonium chloride, tetramethylammonium bromide, tetramethylammonium iodide, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide, tetrapropylammonium chloride, tetrapropylammonium bromide, tetrapropylammonium iodide, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, tetrapentylammonium chloride, tetrapentylammonium bromide, and tetrapentylammonium iodide; alkali metal halides; chlorine, bromine, iodine, etc., can be used, and one or more of these can be used. Among these, it is preferable to use a compound containing iodine as the halogen atom in order to increase the yield of the resulting carboxylic acid.

[0067] When the reaction step is carried out by a flow reaction method, the amount of the reaction accelerator used is preferably 0.02 to 10 moles per mole of alkene contained in the raw material. With such an amount, carboxylic acids and / or carboxylic acid esters can be produced in a higher yield while keeping manufacturing costs down. The amount of reaction accelerator used is more preferably 0.05 to 5 moles, and even more preferably 0.10 to 2 moles. Furthermore, when the reaction process is carried out by a batch reaction method, the amount is preferably 0.01 to 10 moles per mole of metal atoms contained in the catalyst. More preferably, the amount is 0.02 to 5 moles per mole of metal atoms contained in the catalyst, and even more preferably, 0.05 to 2 moles.

[0068] The reaction raw materials in the reaction step of the method for producing carboxylic acids and / or carboxylic acid esters of the present invention may include a solvent. The solvent is not particularly limited as long as the reaction proceeds, but it can be: water; alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol; aromatic or aliphatic hydrocarbons such as benzene, toluene, xylene, cyclohexane, n-hexane, n-decane, n-undecane, n-tridecane; carboxylic acids such as acetic acid, difluoroacetic acid, trifluoroacetic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid; ester compounds such as ethyl acetate; ketone compounds such as acetone and methyl ethyl ketone; cyclic ether compounds such as tetrahydrofuran and dioxane; dibutylene Examples include linear ether compounds such as ethers and diisopropyl ether; halogenated hydrocarbons such as dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, 1,2-dichloroethylene, trichloroethylene, and tetrachloroethylene; sulfoxides such as dimethyl sulfoxide; amides such as N,N-dimethylformamide and N-methylpyrrolidone; and ureas such as tetramethylurea and N,N'-dimethylimidazolidinone. One or more of these can be used.

[0069] When the step of reacting the alkene represented by formula (2) with formic acid and / or a formic acid ester is carried out by a flow reaction method, the amount of solvent used is preferably 0 to 200 moles per mole of the alkene represented by formula (2). More preferably, it is 0 to 100 moles per mole of the alkene represented by formula (2), and even more preferably, it is 0 to 50 moles. Furthermore, when the step of reacting the alkene represented by formula (2) with formic acid and / or formic acid ester is carried out by a batch reaction method, the amount of solvent used is preferably 0 to 200 moles per mole of the alkene represented by formula (2). More preferably, it is 0 to 100 moles per mole of the alkene represented by formula (2), and even more preferably, it is 0 to 50 moles.

[0070] The reaction raw materials in the reaction step of the method for producing carboxylic acids or carboxylic acid esters of the present invention may include additives other than reaction accelerators and solvents. Examples of additives other than reaction accelerators and solvents include acidic substances such as p-toluenesulfonic acid (pTSA), p-toluenesulfonic acid (pTSA·H2O) monohydrate, benzenesulfonic acid, benzenesulfonic acid monohydrate, methanesulfonic acid, ethanesulfonic acid, trifluoromethanesulfonic acid, difluoroacetic acid, trifluoroacetic acid, and bis(trifluoromethanesulfonyl)imide, and one or more of these can be used.

[0071] When the step of reacting the alkene represented by formula (2) with formic acid and / or formic acid ester is carried out by a flow reaction method, the amount of additives other than reaction accelerators and solvents used is preferably 0 to 10 moles per mole of the alkene represented by formula (2). More preferably, it is 0 to 5 moles per mole of the alkene represented by formula (2), and even more preferably, it is 0 to 1 mole. Furthermore, when the step of reacting the alkene represented by formula (2) with formic acid and / or formic acid ester is carried out by a batch reaction method, the amount of additives other than reaction accelerators and solvents used is the same as when it is carried out by the flow reaction method described above.

[0072] The method for producing carboxylic acids and / or carboxylic acid esters of the present invention may include other steps, as long as it includes a step of reacting an alkene represented by formula (2) with formic acid and / or a formic acid ester. For example, the method for producing carboxylic acids of the present invention can be performed in a first step of reacting carbon dioxide and hydrogen to produce formic acid, and then in a second step, the carboxylic acid can be produced by reacting the formic acid produced in the first step with an alkene. A method for producing carboxylic acids and / or carboxylic acid esters including such a first step and a second step is one of the preferred embodiments of the present invention. In this case, the first step of reacting carbon dioxide and hydrogen to produce formic acid can also be performed using a flow reaction method or a batch reaction method. Other processes include the purification and extraction of the manufactured carboxylic acid.

[0073] In addition to the method of producing a carboxylic acid by first reacting carbon dioxide and hydrogen to produce formic acid, and then in the second step reacting the formic acid produced in the first step with an alkene, it is also possible to produce a carboxylic acid by directly reacting the alkene represented by formula (2) with carbon dioxide and hydrogen. A method for producing a carboxylic acid that includes a step of reacting the alkene represented by formula (2) with carbon dioxide and hydrogen in the presence of the metal-based immobilized catalyst of the present invention is also one of the present inventions. The step of reacting the alkene represented by formula (2) with carbon dioxide and hydrogen in the presence of the metal-based immobilized catalyst of the present invention can also be carried out using a flow reaction method or a batch reaction method.

[0074] When the process of reacting the alkene represented by formula (2) with carbon dioxide and hydrogen is carried out by a flow reaction method, the flow rate of the reaction raw materials containing the alkene, carbon dioxide and hydrogen represented by formula (2) is expressed in liquid space velocity (LHSV). Considering the amount produced, the efficiency of production and the yield of the product, the flow rate is 0.1 to 100 h. -1Preferably, 0.1 to 50 hours. -1 And more preferably, 0.1 to 40 hours -1 Furthermore, when expressing the hydrogen flow rate in terms of gas space velocity (GHSV), it ranges from 10 to 3000 h. -1 Preferably, 50 to 1500 h -1 And more preferably, 50 to 1000 hours -1 And most preferably, 50 to 500 hours -1 That is the case. Furthermore, when carried out by a batch reaction method, the amount of hydrogen used is preferably 0.1 to 20 moles per mole of the alkene represented by formula (2) above. More preferably, it is 0.5 to 10 moles per mole of the alkene represented by formula (2) above, and even more preferably, it is 1 to 5 moles. While there are no particular restrictions on the amount of carbon dioxide used, in addition to being a reaction raw material, carbon dioxide is a non-flammable gas and therefore also serves as a diluent for safely handling flammable gases such as alkenes and hydrogen gas. Accordingly, the amount of carbon dioxide can be set appropriately from the perspective of both productivity and the safety of the manufacturing process. Carbon dioxide may be used in large excess relative to the alkenes or hydrogen gas represented by formula (1) above, but for example, it is preferable to use 0.1 to 200 moles of carbon dioxide per mole of alkene represented by formula (1) above. More preferably, it is used in a ratio of 0.5 to 150 moles per mole of alkene represented by formula (1) above, and even more preferably, it is used in a ratio of 1 to 100 moles.

[0075] The reaction conditions, reaction accelerators, other additives, and types and amounts of solvent used when producing a carboxylic acid by reacting the alkene represented by formula (2) with carbon dioxide and hydrogen are all the same as those used when producing a carboxylic acid and / or carboxylic acid ester by reacting the alkene represented by formula (2) with formic acid and / or formic acid ester as described above. [Examples]

[0076] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "parts" means "parts by weight" and "%" means "mass%".

[0077] Catalyst Synthesis Example 1 All catalyst synthesis was carried out in a glove box under a nitrogen atmosphere. 10.0 g of immobilized support (Sigma-Aldrich, 2-Diphenylphosphinoethyl-functionalized silica gel, P atom content 1.18 mmol-P / g, particle size 38-75 μm), pre-dried under reduced pressure at 80°C for 3 hours, and 250.0 g of anhydrous toluene (Kanto Chemical Co., Ltd.) were weighed and stirred for 1 hour to obtain a homogeneous suspension. While stirring the obtained suspension, a Rh complex solution, prepared by dissolving 0.765 g of Rh2Cl2(CO)4 complex (Fujifilm Wako Pure Chemical Industries, Ltd.) in 70.0 g of anhydrous toluene (Kanto Chemical Co., Ltd.), was slowly added dropwise. After addition, the suspension was left at room temperature for 15 hours while stirring to allow for immobilization and maturation. After maturation, the suspension was further immobilized at 80°C for 3 hours while stirring. The obtained suspension was separated into solid and liquid by vacuum filtration, and the resulting solid was washed with 100.0 g of dehydrated toluene (manufactured by Kanto Chemical Co., Ltd.) while vacuum filtration. The washed solid was dried under reduced pressure at room temperature for 15 hours, and then further dried under reduced pressure at 80°C for 3 hours. The resulting dried product was used as the Rh-based immobilized catalyst 1.0Rh-3.0DPPE-SiO2.

[0078] Catalyst Synthesis Examples 2-9 An Rh-based immobilized catalyst was synthesized in the same manner as in Catalyst Synthesis Example 1, except that the amount of Rh2Cl2(CO)4 complex and dehydrated toluene used in the Rh complex solution was changed as shown in Table 1.

[0079] [Table 1]

[0080] 1. Production by batch reaction method Example 1 All batch reaction methods used a 30 ml Hastelloy pressure reactor. Cyclohexene (0.33 g, 3.96 mmol), formic acid (0.65 g, 14.2 mmol), and p-toluenesulfonic acid monohydrate (0.13 g, 0.70 mmol) were added to acetic acid (4.46 g, 74.2 mmol) and pre-dissolved. The resulting mixed solution, along with the immobilized catalyst 1.0Rh-3.0DPPE-SiO2 (0.50 g, Rh content 0.19 mmol) synthesized in Catalyst Synthesis Example 1, was added to a pressure reactor and sealed. The sealed pressure reactor was heated to 180°C in an aluminum block electric furnace and the reaction was carried out for 2.5 hours. After cooling, the contents of the pressure reactor were recovered, and qualitative and quantitative analysis of the reaction products contained in the recovered material was performed using a gas chromatography (GC) apparatus equipped with an FID detector. The internal standard method was used for quantitative analysis by GC. Qualitative analysis by GC revealed that the main product is cyclohexanecarboxylic acid (C6H 11 Along with COOH, cyclohexane (C6H 12 ), iodocyclohexane (C6H 11 I) Acetoxycyclohexane (C6H 11 By-products such as OAc were detected. Quantitative analysis revealed that the cyclohexene conversion rate (C6H) was high. 10 The conversion rate and the selectivity of each product were calculated. The results are shown in Table 3. The formulas used for these calculations are as follows: C6H 10 Conversion rate (mol%) = (1 - (number of moles of cyclohexene in the recovered material) / (number of moles of cyclohexene charged into the pressure reactor)) × 100 Selectivity of each product (mol%) = ((moles of product in the recovered material) / (moles of cyclohexene charged into the pressure reactor)) × 100 / (C6H 10 Conversion rate) × 100 In this example, cyclohexanecarboxylic acid could be produced with a selectivity of 0.3 mol% using an immobilized catalyst. Furthermore, it was confirmed that acetoxycyclohexane, an intermediate in the production of cyclohexanecarboxylic acid from cyclohexene, could be produced with a selectivity of 58.0 mol%. This acetoxycyclohexane can be entirely converted back into cyclohexanecarboxylic acid by appropriately changing the reaction conditions or by recycling it and using it again in the reaction with the reaction materials.

[0081] Example 2 Cyclohexene (0.32 g, 3.84 mmol), formic acid (0.65 g, 14.1 mmol), p-toluenesulfonic acid monohydrate (0.13 g, 0.69 mmol), and methyl iodide (0.27 g, 1.90 mmol) as a reaction accelerator were added to acetic acid (4.18 g, 69.6 mmol) and pre-dissolved. The resulting mixed solution and the immobilized catalyst 1.0Rh-3.0DPPE-SiO2 (0.49 g, Rh content 0.19 mmol) synthesized in Catalyst Synthesis Example 1 were added to a pressure reactor and sealed. The sealed pressure reactor was heated to 140°C in an aluminum block type electric furnace and the reaction was carried out for 2.5 hours. The contents of the pressure reactor were recovered, and qualitative and quantitative analysis of the reaction products contained in the recovered material was performed in the same manner as in Example 1. The results are shown in Table 3. In this example, cyclohexanecarboxylic acid was successfully produced with a selectivity of 4.3 mol% using an immobilized catalyst. Furthermore, it was confirmed that iodocyclohexane, an intermediate in the production of cyclohexanecarboxylic acid from cyclohexene, could be produced with a selectivity of 12.8 mol%, and acetoxycyclohexane with a selectivity of 16.9 mol%. These intermediates can all be converted back to cyclohexanecarboxylic acid by appropriately changing the reaction conditions or by recycling them and using them again in the reaction with the reaction raw materials.

[0082] Examples 3-22, Comparative Examples 1-3 The reaction was carried out in the same manner as in Example 1, except that the reaction conditions were changed as shown in Table 2. Qualitative and quantitative analysis of the reaction product was also performed. The results are shown in Table 3.

[0083] [Table 2]

[0084] [Table 3]

[0085] 2. Production by flow reaction method Example 23 For the flow reaction method, Hastelloy reaction tubes with an inner diameter of 8 mm and a length of 100 mm, or an inner diameter of 10 mm and a length of 100 mm, were used as fixed-bed flow reactors. 1.5 ml (0.9 g, Rh content 0.34 mmol) of the immobilized catalyst 1.0Rh-3.0DPPE-SiO2 synthesized in Catalyst Synthesis Example 1 was packed into a Hastelloy reaction tube with an inner diameter of 8 mm and a length of 100 mm to prepare a fixed-bed flow reactor. Two reaction raw materials were prepared: Raw material A, consisting of 10% cyclohexene, 20% formic acid, 4% p-toluenesulfonic acid monohydrate, and 66% acetic acid; and Raw material B, consisting of 11% methyl iodide and 89% acetic acid. First, nitrogen gas was flowed into the reactor at a flow rate of 10 ml / min for 30 minutes, and then raw material A was flowed at a rate of 3.3 g / min and raw material B at a rate of 2.7 g / min for 10 minutes to fully fill the reactor with the reaction raw materials. Subsequently, the flow rates of the raw materials were changed to 0.33 g / min for raw material A and 0.27 g / min for raw material B, and the reactor outlet pressure was increased until it reached 1.0 MPa, after which it was confirmed that the pressure was stable. After confirming the stability of the pressure, the reactor outlet pressure was maintained at 1.0 MPa, and the reaction temperature was raised to 180°C over 10 minutes. The point at which the reaction temperature reached 180°C was considered the start of the reaction, and this time was defined as reaction time 0 minutes. The reaction conditions at this time were: reaction temperature 180°C, reaction pressure 1.0 MPa, and the composition of the reaction raw materials was 1 mol of cyclohexene, 3.6 mol of formic acid, 0.5 mol of methyl iodide, 0.2 mol of p-toluenesulfonic acid monohydrate, and 19.1 mol of acetic acid. The flow rate of the reaction raw materials (total flow rate of raw material A and raw material B) was 0.60 g / min (volume flow rate 0.55 ml / min, LHSV 21.97 h). -1 ) After the reaction started, the effluent from the reactor was cooled and collected in an ice bath at predetermined time intervals (15-25 minutes, 30-40 minutes, 45-55 minutes, 60-70 minutes, 90-100 minutes, 120-130 minutes, and 150-160 minutes). In the following, this cooled and collected effluent will be referred to as "effluent." A portion of the effluent was collected, and qualitative and quantitative analysis of the reaction products contained in the recovered material was performed using a gas chromatography (GC) system equipped with a FID detector. An internal standard method was employed for quantitative analysis by GC. Qualitative analysis by GC revealed that, as in the batch reaction method, the main product was cyclohexanecarboxylic acid (C6H 11 Along with COOH, cyclohexane (C6H 12 ), iodocyclohexane (C6H 11 I) Acetoxycyclohexane (C6H 11 By-products such as OAc were detected. Quantitative analysis revealed that the cyclohexene conversion rate (C6H) was high. 10 The conversion rate and the selectivity of each product were calculated. The results are shown in Table 6. The formulas used for these calculations are as follows: C6H 10 Conversion rate (mol%) = (1 - (number of moles of cyclohexene in the effluent) / (number of moles of cyclohexene supplied to the reactor during the time the effluent was cooled and collected)) × 100 Selectivity of each product (mol%) = ((moles of product in the effluent) / (moles of cyclohexene supplied to the reactor during the time the effluent was cooled and collected)) × 100 / (C6H 10 Conversion rate) × 100 In this embodiment, cyclohexanecarboxylic acid could be produced using an immobilized catalyst and a flow reaction method. For example, it was confirmed that during a reaction time of 120 to 130 minutes, cyclohexanecarboxylic acid could be produced with a selectivity of 3.8%, iodocyclohexane (an intermediate in the production of cyclohexanecarboxylic acid from cyclohexene) with a selectivity of 31.8%, and acetoxycyclohexane with a selectivity of 39.0 mol%. This iodocyclohexane and acetoxycyclohexane can all be converted back to cyclohexanecarboxylic acid by appropriately changing the reaction conditions or by continuously separating them from cyclohexanecarboxylic acid in a purification process, then continuously recycling them and using them again in the reaction together with the reaction raw materials.

[0086] Examples 24-33, Comparative Examples 4-6 The reaction was carried out in the same manner as in Example 23, except that the reaction conditions were changed as shown in Tables 4 and 5. The results are shown in Tables 6 and 7.

[0087] [Table 4]

[0088] [Table 5]

[0089] [Table 6]

[0090] [Table 7] The DPPE-SiO2 used as a catalyst in Comparative Examples 5 and 6, described in Tables 4 and 6, is the immobilization support used to immobilize the metal complex. Specifically, it is an immobilization support (Sigma-Aldrich, 2-Diphenylphosphinoethyl-functionalized silica gel, P atom content 1.18 mmol-P / g, particle size 38-75 μm) that was pre-dried under reduced pressure at 80°C for 3 hours, and was used before the metal complex was immobilized.

Claims

1. A metal-based immobilized catalyst for reactions involving alkenes and formic acid and / or formic acid esters, or for reactions involving alkenes, hydrogen, and carbon dioxide, to produce carboxylic acids and / or carboxylic acid esters, characterized by having a site on an inorganic oxide where a metal complex containing at least one metal atom selected from the group consisting of Rh, Pd, and Ni is immobilized via a linker and a ligand containing a phosphorus atom, which is an alkylene group, an arylene group, or a group formed by a combination thereof.

2. A metal-based immobilized catalyst for the reaction of an alkene with formic acid and / or a formic acid ester according to claim 1, characterized in that the linker is a methylene group, an ethylene group, a propylene group, a phenylene group, or a group formed by a combination thereof.

3. A metal-based immobilized catalyst for a reaction of an alkene with formic acid and / or a formic acid ester, or a reaction of an alkene with hydrogen and carbon dioxide to produce a carboxylic acid and / or a carboxylic acid ester, according to claim 1 or 2, wherein the inorganic oxide is an oxide of silicon, aluminum, titanium, or zirconium, or a composite oxide containing two or more of these.

4. A metal-based immobilized catalyst for the reaction of an alkene with formic acid and / or formic acid ester, or for the reaction of an alkene with hydrogen and carbon dioxide to produce a carboxylic acid and / or carboxylic acid ester, as described in any one of claims 1 to 3, characterized in that the number of moles of metal atoms contained in the immobilized metal complex is 5 to 250 mmol per 100 g of a support having a linker and ligand on an inorganic oxide.

5. A step of reacting an inorganic oxide that is a support with a compound that will become a linker to obtain a support to which an alkylene group, an arylene group, or a group formed by a combination thereof will be bonded, A step of reacting a ligand compound with a support to which the linker is attached, thereby attaching a ligand containing a phosphorus atom to the linker, The following formula (1); L ｌ MX ｍ (1) The process includes a step of reacting a metal complex represented by (wherein L represents a ligand containing at least one atom selected from the group consisting of phosphorus, nitrogen, oxygen, and sulfur atoms, either identical or different; l and m represent the number of ligands, each being between 0 and 8; M represents a metal atom selected from the group consisting of Rh, Pd, and Ni; X represents a halogen atom, hydrogen atom, alkyl group, or hydroxyl group) with a ligand containing a phosphorus atom bonded to the linker to immobilize it. A method for producing a metal-based immobilized catalyst for reactions involving the reaction of an alkene with formic acid and / or a formic acid ester, or for the reaction of an alkene with hydrogen and carbon dioxide to produce a carboxylic acid and / or a carboxylic acid ester.

6. Formula (2) below; 【Chemistry 1】 (In the formula, R １ , R ２ R represents a hydrogen atom or an organic group having 1 to 24 carbon atoms, either identical or different. １ and R ２ The two may be linked together. From an alkene represented by ( ), the following equation (3): 【Chemistry 2】 (wherein, R １ , R ２ is the same as in formula (2). R ３ represents a hydrogen atom or an organic group having 1 to 24 carbon atoms.) A method for producing a carboxylic acid and / or a carboxylic acid ester represented by the formula: The manufacturing method includes a step of reacting an alkene represented by formula (2) with formic acid and / or a formic acid ester, or reacting an alkene represented by formula (2) with hydrogen and carbon dioxide, in the presence of a metal-based immobilized catalyst as described in any of claims 1 to 4. A method for producing carboxylic acids and / or carboxylic acid esters, characterized by the above.

7. The method for producing a carboxylic acid and / or carboxylic acid ester according to claim 6, characterized in that the reaction step is carried out by a flow reaction method using a fixed-bed flow reactor.

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