Method for producing aliphatic aldehyde

Abstract

Provided is a production method with which it is possible to efficiently produce an aliphatic aldehyde by oxidizing a C4 or higher aliphatic primary alcohol. A method for producing an aliphatic aldehyde including a step for oxidizing a C4 or higher aliphatic primary alcohol using molecular oxygen in the presence of a ruthenium-supported catalyst, wherein the ruthenium-supported catalyst contains ruthenium supported on a carrier, the carrier is a porous oxide, the surface area per unit mass of the ruthenium is 60 m2 / g or greater, and the mesopore volume of the ruthenium-supported catalyst is 0.15 mL / g or greater.

Description

Method for producing aliphatic aldehydes

[0001] This invention relates to a method for producing aliphatic aldehydes.

[0002] Conventionally, a method for producing carbonyl compounds has been known in which alcohols are oxidized in the presence of a metal catalyst to obtain carbonyl compounds.

[0003] For example, Japanese Patent Publication No. 2014-108393 discloses a paper catalyst structure containing metal oxide fibers, alumina, and ruthenium. In this paper catalyst structure, a coating layer containing γ-structured alumina is formed on the surface of the metal oxide fibers, and the ruthenium is held by the coating layer containing γ-structured alumina. This paper catalyst structure has been reported to have high catalytic activity and is suitable as an oxidation catalyst for alcohols.

[0004] Japanese Patent Publication No. 2010-202555 discloses a method for producing carbonyl compounds, characterized by oxidizing a specific alcohol in the presence of a catalyst in which at least one metal selected from ruthenium and platinum is supported on an activated carbon carrier, and oxygen, to produce a carbonyl compound consisting of an aldehyde compound or a ketone compound. It has been reported that this method allows for the production of carbonyl compounds from various alcohols in higher yields.

[0005] Japanese Patent Publication No. 2004-894 discloses a method for producing ruthenium-supported alumina, characterized by suspending alumina in a solution containing trivalent ruthenium and then adding a base. It has been reported that this method of oxidizing alcohol using ruthenium-supported alumina can oxidize alcohol with a high conversion rate, enabling the productive production of ketones, aldehydes, carboxylic acids, etc. Japanese Patent Publication No. 2008-201755 reports a method for producing carbonyl compounds, comprising oxidizing an alcohol in an oxygen atmosphere and in the presence of a polymer-immobilized ruthenium catalyst and a reoxidizing agent, wherein the polymer-immobilized ruthenium catalyst is formed by supporting ruthenium on a crosslinked polymer, the crosslinked polymer has aromatic side chains, hydrophilic side chains and crosslinking groups, and the reoxidizing agent is used in an amount of 0.01 to 1.0 equivalents relative to the substrate. Japanese Patent Publication No. 11-226417 reports an oxidation catalyst system composed of (A) a ruthenium compound and (B) dioxybenzenes or their oxidized counterparts. This method is reported to enable the high-yield oxidation of alcohols with molecular oxygen using only a small amount of catalyst.

[0006] The present invention relates to a method for producing an aliphatic aldehyde, comprising the step of oxidizing an aliphatic primary alcohol having 4 or more carbon atoms with molecular oxygen in the presence of a ruthenium-supported catalyst, wherein the ruthenium-supported catalyst comprises ruthenium supported on a carrier, the carrier is a porous oxide, and the surface area per unit mass of ruthenium is 60 m². 2 The present invention relates to a method for producing aliphatic aldehydes, wherein the amount is 0.15 mL / g or more, and the mesopore volume of the ruthenium-supported catalyst is 0.15 mL / g or more. Detailed description of the invention

[0007] However, while the methods described in Patent Documents 1 and 2 are suitable for oxidizing aromatic alcohols and aliphatic secondary alcohols from the viewpoint of reactivity, they are not necessarily suitable for oxidizing aliphatic primary alcohols. Furthermore, the catalyst reaction efficiency in the method described in Patent Document 3 is insufficient.

[0008] Therefore, the present invention aims to provide a method for efficiently producing aliphatic aldehydes by oxidizing aliphatic primary alcohols having four or more carbon atoms.

[0009] The present invention relates to a method for producing an aliphatic aldehyde, comprising the step of oxidizing an aliphatic primary alcohol having 4 or more carbon atoms with molecular oxygen in the presence of a ruthenium-supported catalyst, wherein the ruthenium-supported catalyst contains ruthenium supported on a carrier, the carrier is a porous oxide, and the surface area per unit mass of ruthenium is 60 m². 2 The present invention relates to a method for producing aliphatic aldehydes, wherein the amount is 0.15 mL / g or more, and the mesopore volume of the ruthenium-supported catalyst is 0.15 mL / g or more.

[0010] The method of the present invention has the advantage of efficiently producing aliphatic aldehydes by oxidizing aliphatic primary alcohols having four or more carbon atoms (hereinafter also simply referred to as aliphatic primary alcohols).

[0011] The present inventors have discovered that by using a ruthenium-supported catalyst containing ruthenium supported on a carrier, wherein the ruthenium has a specific metallic specific surface area and the catalyst has a specific mesopore volume, it is possible to efficiently produce aliphatic aldehydes by oxidizing aliphatic primary alcohols having four or more carbon atoms, thus completing the present invention.

[0012] [Method for producing aliphatic aldehydes] The present invention relates to a method for producing aliphatic aldehydes, comprising the step of oxidizing an aliphatic primary alcohol having 4 or more carbon atoms with molecular oxygen in the presence of a ruthenium-supported catalyst, wherein the ruthenium-supported catalyst contains ruthenium supported on a carrier, the carrier is a porous oxide, and the surface area per unit mass of ruthenium is 60 m². 2 The present invention relates to a method for producing aliphatic aldehydes, wherein the amount is 0.15 mL / g or more, and the mesopore volume of the ruthenium-supported catalyst is 0.15 mL / g or more.

[0013] The present invention is characterized by the use of a specific ruthenium-supported catalyst in its manufacturing method. This method allows for the efficient production of aliphatic aldehydes by oxidizing aliphatic primary alcohols having four or more carbon atoms. This is presumed to be because the hydroxyl group, which is the active site of aliphatic primary alcohols having four or more carbon atoms, is suitable for the catalyst structure described above.

[0014] Furthermore, according to the manufacturing method of the present invention, aliphatic aldehydes can be produced in a short time by oxidizing aliphatic primary alcohols having four or more carbon atoms. Therefore, it is believed that the side reaction of further oxidizing the aliphatic aldehyde and converting it to a carboxylic acid can be suppressed.

[0015] <Aliphatic primary alcohols having 4 or more carbon atoms> In the present invention, the aliphatic primary alcohol having 4 or more carbon atoms may be linear or branched, and may be saturated or unsaturated. From the viewpoint of high reactivity in a short time, the aliphatic primary alcohol is preferably a linear saturated primary alcohol, and more preferably a linear saturated primary alcohol having 8 to 14 carbon atoms.

[0016] From the viewpoint of reactivity, the number of carbon atoms in the aliphatic primary alcohol is preferably 4 or more, more preferably 6 or more, even more preferably 8 or more, and even more preferably 10 or more. Similarly, it is preferably 30 or less, more preferably 22 or less, even more preferably 14 or less, and even more preferably 12 or less. From the viewpoint of reactivity, the number of carbon atoms in the aliphatic primary alcohol is preferably 4 to 30, more preferably 6 to 22, even more preferably 6 to 14, even more preferably 8 to 14, even more preferably 10 to 14, even more preferably 8 to 12, and even more preferably 12.

[0017] Specifically, the aliphatic primary alcohols include: C4 alcohols such as n-butyl alcohol and iso-butyl alcohol; C6 alcohols such as hexyl alcohol and isohexyl alcohol; C8 alcohols such as n-octyl alcohol (octanol), isooctyl alcohol, and 2-ethylhexyl alcohol; C9 alcohols such as n-nonyl alcohol, isononyl alcohol, and 3,5,5-trimethylhexyl alcohol; C10 alcohols such as n-decyl alcohol, 3,7-dimethyloctyl alcohol, and 2-propylheptyl alcohol; and n-undecyl alcohol. Examples include C11 alcohols such as kohl and 2-methyldecanol; C12 alcohols such as n-dodecyl alcohol (lauryl alcohol), 2-methylundecanol, and 2-butyloctanol; C14 alcohols such as myristyl alcohol (1-tetradecanol); C18 alcohols such as hexadecyl alcohols, oleyl alcohol, and stearyl alcohol; and behenyl alcohol, eicosyl alcohols, geraniol, nerol, citronellol, cyclopentylmethanol, cyclopentenylmethanol, cyclohexylmethanol, and cyclohexenylmethanol. The aliphatic primary alcohol is preferably a linear saturated primary alcohol with 4 to 30 carbon atoms, more preferably 6 to 22, even more preferably 6 to 14, even more preferably 8 to 14, even more preferably 10 to 14, even more preferably 8 to 12, and even more preferably 12 carbon atoms.

[0018] <Ruthenium-supported catalyst> In the manufacturing method of the present invention, the ruthenium-supported catalyst has ruthenium supported on a carrier.

[0019] The ruthenium-supported catalyst has a surface area of ​​60 m² per unit mass of ruthenium. 2It is 60 m² / g or more. A large surface area per unit mass of ruthenium means that the particle size of ruthenium is small and ruthenium is widely dispersed on the carrier, that is, dispersed on a carrier with a large pore volume. The surface area per unit mass of ruthenium can be measured by the pulse method, particularly the CO pulse method.

[0020] From the viewpoint of enhancing reactivity, the surface area per unit mass of ruthenium is 60 m 2 ² / g or more, preferably 65 m 2 ² / g or more, preferably 70 m 2 ² / g or more, more preferably 100 m 2 ² / g or more, even more preferably 130 m 2 ² / g or more, and from the same viewpoint, it is 250 m 2 ² / g or less, preferably 200 m 2 ² / g or less, more preferably 190 m 2 ² / g or less, still more preferably 180 m 2 ² / g or less, still more preferably 170 m 2 ² / g or less, still more preferably 160 m 2 ² / g or less. From the viewpoint of enhancing reactivity, the ruthenium surface area per unit mass of ruthenium is 60 m 2 ² / g or more and 250 m 2 ² / g or less, preferably 65 m 2 ² / g or more and 250 m 2 ² / g or less, more preferably 65 m 2 ² / g or more and 200 m 2 ² / g or less, more preferably 70 m 2 ² / g or more and 200 m 2 ² / g or less, still more preferably 70 m 2 ² / g or more and 190 m 2 ² / g or less, even more preferably 70 m 2 ² / g or more and 180 m 2 ² / g or less, more preferably 70 m 2 ² / g or more and 170 m 2 ² / g or less, still more preferably 100 m 2 ² / g or more and 170 m 2 ² / g or less, even more preferably 130 m 2 ² / g or more and 160 m 2 ² / g or less.

[0021] From the viewpoint of reactivity, the particle size of ruthenium is preferably 1 nm or more, more preferably 2 nm or more, and even more preferably 2.5 nm or more. Similarly, from the same viewpoint, it is preferably 20 nm or less, more preferably 10 nm or less, and even more preferably 5 nm or less. This particle size was calculated using the metal surface area and the ratio of the volume when the particle is assumed to be perfectly spherical to the surface area per unit mass of ruthenium. From the viewpoint of reactivity, the particle size of ruthenium is preferably 1 nm or more and 20 nm or less, more preferably 2 nm or more and 10 nm or less, and even more preferably 2.5 nm or more and 5 nm or less.

[0022] The surface area per unit mass of ruthenium can be adjusted during catalyst preparation by increasing the amount of ruthenium compound relative to the raw material carrier, or by using a carrier with a large surface area, i.e., a highly porous carrier. In this case, as will be described later, in order to increase catalytic activity and the surface area per unit mass of ruthenium, it is preferable to reduce the macropores of the carrier and increase the mesopore volume.

[0023] The carrier is a porous oxide. The porous oxide is preferably one or more selected from the group consisting of alumina, titania, zirconia, silica, silica-alumina, magnesia, zeolite, and activated carbon. From the viewpoint of high activity and high selectivity, the carrier is preferably alumina, activated carbon, titania, silica-alumina, or zeolite, with alumina and activated carbon being more preferred. In the present invention, the porous oxide may be used alone or in combination of two or more types.

[0024] The mesopore volume of the ruthenium-supported catalyst is 0.15 mL / g or more. The mesopore volume can be measured by mercury porosimetry according to ASTM D4284-83. Specifically, the measurement is performed by filling a measurement cell containing the sample with mercury and pressurizing the inside of the cell. Then, the amount of mercury that enters is detected by a capacitance detector and the pore volume is measured. Alternatively, the mesopore volume can be calculated by determining the pore distribution by modeling the pores as cylindrical. A catalyst having the aforementioned mesopore volume of 0.15 mL / g or more is considered to be a catalyst with a pore size suitable for the reaction field of the oxidation reaction of the aliphatic primary alcohol.

[0025] The mesopore volume of the ruthenium-supported catalyst is preferably 0.15 mL / g or more, preferably 0.2 mL / g or more, more preferably 0.25 mL / g or more, from the viewpoint of increasing the reactivity of aliphatic primary alcohols having 4 or more carbon atoms and further suppressing the oxidation of aldehydes to carboxylic acids, and from the viewpoint of catalyst preparation, preferably 0.5 mL / g or less, more preferably 0.45 mL / g or less, and even more preferably 0.4 mL / g or less. The mesopore volume of the catalyst is preferably 0.15 mL / g or more and 0.5 mL / g or less, more preferably 0.2 mL / g or more and 0.5 mL / g or less, even more preferably 0.25 mL / g or more and 0.5 mL / g or less, even more preferably 0.25 mL / g or more and 0.45 mL / g or less, and even more preferably 0.25 mL / g or more and 0.4 mL / g or less, from the viewpoint of increasing the reactivity of aliphatic primary alcohols having 4 or more carbon atoms and further suppressing the oxidation of aldehydes to carboxylic acids, and from the viewpoint of catalyst preparation.

[0026] The ruthenium metal content in the ruthenium-supported catalyst is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 5% by mass or more, relative to the entire catalyst, from the viewpoint of reactivity. Similarly, it is preferably 50% by mass or less, more preferably 30% by mass or less, even more preferably 10% by mass or less, and even more preferably less than 10% by mass. The ruthenium metal content in the ruthenium-supported catalyst is preferably 1% by mass or more and 50% by mass or less, more preferably 1% by mass or more and 30% by mass or less, even more preferably 1% by mass or more and 10% by mass or less, even more preferably 1% by mass or more and less than 10% by mass, relative to the entire catalyst, from the viewpoint of reactivity.

[0027] <Method for producing ruthenium-supported catalyst> The ruthenium-supported catalyst used in the present invention has ruthenium supported on a carrier, the carrier is a porous oxide, and the surface area per unit mass of ruthenium is 60 m². 2 A commercially available ruthenium-supported catalyst may be used, having a concentration of 0.15 mL / g or more and a mesopore volume of 0.15 mL / g or more. Alternatively, such a ruthenium-supported catalyst may be manufactured in accordance with known technology or common technical knowledge. Examples of such manufacturing methods include impregnation methods in which ruthenium is impregnated into a support, and liquid-phase reduction methods in which a reducing agent is added.

[0028] An example of a method for producing the ruthenium-supported catalyst used in the present invention is described below. First, the porous oxide is added to a medium such as deionized water and suspended. Then, a solution of the ruthenium compound dissolved in an aqueous solvent such as deionized water is added to this suspension, and the mixture is heated as needed while stirring to adjust the temperature to about 20 to 95°C, preferably 40 to 80°C, to obtain a suspension containing the ruthenium compound. Examples of the ruthenium compound include ruthenium chloride, nitrate, formate, and ammonium salt.

[0029] Next, an alkali is added to the suspension containing the ruthenium compound to adjust the pH to 4-12, preferably 6-11, and hydrolysis is carried out, followed by aging to support the ruthenium component on a porous oxide. There are no particular restrictions on the type of alkali, but ammonia water, alkali metal carbonates such as sodium and potassium, hydroxides, etc., can be used. The time for adjusting the pH and aging is not particularly limited, as long as time is ensured for the ruthenium compound to hydrolyze.

[0030] Next, a reducing agent such as formaldehyde, hydrazine, or sodium borohydride is added to the reaction solution, and the mixture is heated as needed. After reduction treatment at a temperature of approximately 20 to 95°C, preferably 60 to 95°C, the solid-liquid is separated by filtration or the like. The obtained solid is thoroughly washed with water and then dried at a temperature of preferably 140°C or lower under normal or reduced pressure. The reducing agent may be used alone or in combination of two or more. To effectively reduce the supported ruthenium component, the reducing agent is usually used in a ratio of approximately 1 to 50 molars, preferably 15 to 40 molars, relative to the ruthenium. The time for the reduction treatment is not particularly limited, as long as enough time is ensured for the reduction reaction to proceed to the desired extent. Note that the reduction treatment is not necessarily required; the ruthenium component may be supported by hydrolysis, followed by solid-liquid separation, thorough washing of the obtained solid with water, and drying.

[0031] When ruthenium components are supported on porous oxides by hydrolysis as described above, it is not necessarily required to perform operations such as high-temperature calcination or high-temperature reduction under an inert gas atmosphere, which are usually carried out in impregnation methods, and the preparation of the catalyst is simple.

[0032] The ruthenium-supported catalyst obtained in this manner contains ruthenium as metal, preferably in an amount of about 1 to 50% by mass, more preferably 3 to 30% by mass, based on the total amount of catalyst including porous oxides, from the viewpoint of sufficient catalytic activity, selectivity, and economic efficiency. The ruthenium content in the catalyst can be measured by ICP emission spectrometry after melting the catalyst with ammonium bisulfate.

[0033] <Method for producing aliphatic aldehydes> The production method of the present invention includes the step of oxidizing an aliphatic primary alcohol having 4 or more carbon atoms with molecular oxygen in the presence of a ruthenium-supported catalyst. In this step, the molar ratio of ruthenium (mol) to aliphatic primary alcohol having 4 or more carbon atoms (mol), i.e., the molar ratio of ruthenium (mol) / aliphatic primary alcohol having 4 or more carbon atoms (mol), varies depending on the reaction temperature, etc., but is usually preferably 0.001 or more, more preferably 0.005 or more, and even more preferably 0.01 or more from the viewpoint of reactivity, and preferably 0.5 or less, more preferably 0.2 or less, more preferably 0.1 or less, even more preferably 0.05 or less, and even more preferably 0.045 or less from the viewpoint of efficiency. The ratio of ruthenium ( mmol) to aliphatic primary alcohol ( mmol) having 4 or more carbon atoms is preferably 0.001 to 0.5, more preferably 0.001 to 0.2, more preferably 0.001 to 0.1, even more preferably 0.001 to 0.05, even more preferably 0.001 to 0.045, even more preferably 0.005 to 0.1, even more preferably 0.005 to 0.05, even more preferably 0.005 to 0.045, even more preferably 0.01 to 0.05, and even more preferably 0.01 to 0.045.

[0034] The molecular oxygen (referring to elemental molecular oxygen (oxygen gas); the same applies hereinafter) functions as an oxidizing agent in this step. This molecular oxygen is present in the reaction system of the present invention and only needs to be in contact with an aliphatic primary alcohol having 4 or more carbon atoms. Specifically, this step can be carried out in an atmospheric environment. Furthermore, it is preferable to carry out this step in an oxygen atmosphere because the oxidation reaction of aliphatic primary alcohols having 4 or more carbon atoms can be carried out more efficiently. An oxygen atmosphere may include gases other than oxygen, such as air, and may be 100% oxygen, or it may include oxygen and an inert gas such as nitrogen, helium, or argon. In an oxygen atmosphere, the oxygen gas concentration is preferably 5% by volume or more, and more preferably 10% by volume or more. In an oxygen atmosphere, it is preferable to have a high concentration of oxygen, as a high concentration of oxygen can increase the reaction efficiency.

[0035] This step may be carried out in the presence of a solvent. The solvent is preferably one that can dissolve the aliphatic primary alcohol, and examples include water and organic solvents. Examples of the solvent include aromatic solvents such as toluene, liquid paraffin, and hydrocarbon solvents such as squalene. Among these, from the viewpoint of reaction efficiency, aromatic organic solvents having 6 to 40 carbon atoms are preferred, and more preferably 6 to 12 carbon atoms. The solvent can be used alone or in combination of two or more.

[0036] In this step, the ratio of solvent (mL) to aliphatic primary alcohol (mL) having 4 or more carbon atoms, i.e., solvent (mL) / aliphatic primary alcohol (mL) having 4 or more carbon atoms, is preferably 0.01 or more, more preferably 0.05 or more, and even more preferably 0.1 or more, from the viewpoint of reactivity, and similarly, preferably 6 or less, more preferably 4 or less, and even more preferably 2 or less. The ratio of solvent to aliphatic primary alcohol having 4 or more carbon atoms is preferably 0.01 or more and 6 or less, more preferably 0.05 or more and 4 or less, and even more preferably 0.1 or more and 2 or less, from the viewpoint of reactivity.

[0037] The initial aldehyde activity value (per unit time and unit amount of catalyst) is preferably 2 mmol / g / hr or more, more preferably 3 mmol / g / hr or more, and even more preferably 4 mmol / g / hr or more, with an upper limit of 10 mmol / g / hr or less. Here, mol is the number of moles of aldehyde after the reaction, g is the amount of ruthenium-supported catalyst, and hr is the reaction time, and is calculated according to the formula in the examples.

[0038] The reaction temperature in this step is not particularly limited. When heating is used, the reaction temperature is preferably below the boiling point of the solvent used. From the viewpoint of reactivity, the reaction temperature is preferably 60°C or higher, more preferably 70°C or higher, and even more preferably 80°C or higher. From the viewpoint of productivity, it is preferably 200°C or lower, more preferably 180°C or lower, and even more preferably 170°C or lower. From the viewpoint of reactivity and productivity, the reaction temperature is preferably 60°C to 200°C, more preferably 70°C to 180°C, and even more preferably 80°C to 170°C.

[0039] The pressure used in this process is not limited, but it is preferable to perform it at atmospheric pressure or under reduced pressure.

[0040] The manufacturing method of the present invention is suitable not only for batch production but also for continuous flow production, as it can produce aldehydes in a short time and with high yield. The manufacturing method of the present invention further includes a step of oxidizing an aliphatic primary alcohol having 4 or more carbon atoms with molecular oxygen in the presence of one or more compounds selected from N-oxyl compounds and phenol derivatives, in addition to a ruthenium-supported catalyst.

[0041] <N-oxyl compound / N-oxide compound> The oxidation step of the production method of the present invention is preferably carried out in the presence of an N-oxyl compound and / or an N-oxide compound (hereinafter collectively referred to as NO compound). The N-oxyl compound / N-oxide compound is preferably one or more selected from the group consisting of the compound represented by general formula (I), the compound represented by general formula (II), and the compound represented by general formula (III).

[0042] <<Compounds represented by general formula (I)>>

[0043]

[0044] In the formula, R 1 , R 2 , R 3 , and R 4R is a hydrocarbon group having 1 to 5 carbon atoms, which may be substituted with a hydrogen atom or a substituent, and the substituent is one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group, a phenoxy group and an acyloxy group. 5 is either an oxygen atom or a methylene group.

[0045] The aforementioned R 1 , R 2 , R 3 , and R 4 From the viewpoint of increasing the yield of aliphatic aldehydes, the number of carbon atoms in the hydrocarbon group is preferably 1 to 3, and more preferably a methyl group, independently of each other.

[0046] The hydrocarbon group having 1 to 5 carbon atoms may be saturated or unsaturated, and may be linear or branched. It may also be alicyclic.

[0047] Specifically, examples of hydrocarbon groups having 1 to 5 carbon atoms include alkyl groups having 1 to 5 carbon atoms, alkenyl groups having 2 to 5 carbon atoms, and cycloalkyl groups having 3 to 5 carbon atoms.

[0048] Examples of alkyl groups having 1 to 5 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, n-pentyl group, i-pentyl group, sec-pentyl group, t-pentyl group, and 2-methylbutyl group.

[0049] Examples of the alkenyl group having 2 to 5 carbon atoms include vinyl group, 1-propenyl group, 2-propenyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 1-pentenyl group, 2-pentenyl group, 3-pentenyl group, and 4-pentenyl group.

[0050] Examples of the cycloalkyl group having 3 to 5 carbon atoms include a cyclopropyl group, a cyclobutyl group, and a cyclopentyl group.

[0051] R 5 From the viewpoint of the yield of aliphatic aldehydes, a methylene group is preferred.

[0052] Examples of halogen atoms that may be contained in the substituent include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0053] Examples of alkoxy groups that may be contained in the substituents include alkoxy groups having 1 to 5 carbon atoms, preferably alkoxy groups having 1 to 3 carbon atoms, such as methoxy groups, ethoxy groups, n-propyloxy groups, i-propyloxy groups, and so on.

[0054] An example of an acyloxy group that may be contained in the substituent can be represented by the formula R-CO-O- (wherein R is, for example, hydrogen or an alkyl group having 1 to 5 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms). Specifically, examples of the acyloxy group include formyl, acetyl, propionyl, butyryl, isobutyryl, and valeryl.

[0055] Preferably, in general formula (I), R is selected from the viewpoint of the yield of aliphatic aldehydes. 1 , R 2 , R 3 , and R 4 R is a hydrocarbon group having 1 to 5 carbon atoms, which may be substituted with a hydrogen atom or a substituent, and the substituent is one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group having 1 to 5 carbon atoms, a phenoxy group, and an acyloxy group represented by the formula R-CO-O (wherein R is hydrogen or an alkyl group having 1 to 5 carbon atoms), 5 A methylene group is preferred, and more preferably, in general formula (I), R 1 , R 2 , R 3 , and R 4 These are, independently of each other, a hydrogen atom and an (unsubstituted) hydrocarbon group having 1 to 5 carbon atoms, and R 5 A methylene group is preferred, or more preferably, in general formula (I), R 1 , R 2 , R 3 , and R 4R is a hydrocarbon group having 1 to 3 carbon atoms, which may be substituted with a hydrogen atom or a substituent, and the substituent is one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group having 1 to 3 carbon atoms, a phenoxy group, and an acyloxy group represented by the formula R-CO-O (wherein R is hydrogen or an alkyl group having 1 to 3 carbon atoms), 5 A methylene group is preferred, and more preferably, in general formula (I), R 1 , R 2 , R 3 , and R 4 These are, independently of each other, a hydrogen atom and an (unsubstituted) hydrocarbon group having 1 to 3 carbon atoms, and R 5 A methylene group is preferred, and more preferably, in general formula (I), R 1 , R 2 , R 3 , and R 4 These are, independently of each other, a hydrogen atom or a methyl group, and R 5 A methylene group is preferred.

[0056] A compound represented by general formula (I) is, for example, TEMPO (2,2,6,6-tetramethylpiperidine N-oxyl).

[0057] <<Compounds represented by general formula (II)>>

[0058]

[0059] In the formula, R 11 , R 12 , R 13 , and R 14 R is a hydrocarbon group having 1 to 5 carbon atoms, which may have a hydrogen atom or substituents, and the substituent is one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group, a phenoxy group, and an acyloxy group. 15 is either an oxygen atom or a methylene group.

[0060] The aforementioned R 11 , R 12 , R 13 , and R 14The preferred number of carbon atoms of the hydrocarbon group and the specific compounds are the same as the number of carbon atoms and the compounds described for R in the general formula (I) above. 1 R 2 R 3 R 4 and R 15 is preferably an oxygen atom from the viewpoint of the yield of aliphatic aldehyde.

[0061] Preferably, in the general formula (II), from the viewpoint of the yield of aliphatic aldehyde, R 11 R 12 R 13 and R 14 are each independently a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms which may be substituted with a substituent, and the substituent is selected from the group consisting of a halogen atom, a nitro group, an alkoxy group having 1 to 5 carbon atoms, a phenoxy group, and an acyloxy group represented by the formula R-CO-O (wherein R is hydrogen or an alkyl group having 1 to 5 carbon atoms), and R 15 is preferably an oxygen atom, and more preferably, in the general formula (II), R 11 R 12 R 13 and R 14 are each independently a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms (unsubstituted), and R 15 is preferably an oxygen atom, or more preferably, in the general formula (II), R 11 R 12 R 13 and R 14 are each independently a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms which may be substituted with a substituent, and the substituent is selected from the group consisting of a halogen atom, a nitro group, an alkoxy group having 1 to 3 carbon atoms, a phenoxy group, and an acyloxy group represented by the formula R-CO-O (wherein R is hydrogen or an alkyl group having 1 to 3 carbon atoms), and R 15 is preferably an oxygen atom, and still more preferably, in the general formula (II), R 11 R 12 R 13 and R 14These are, independently of each other, a hydrogen atom and an (unsubstituted) hydrocarbon group having 1 to 3 carbon atoms, and R 15 The atom is preferably an oxygen atom, and more preferably, in general formula (II), R 11 , R 12 , R 13 , and R 14 These are, independently of each other, a hydrogen atom or a methyl group, and R 15 An oxygen atom is preferred.

[0062] A compound represented by general formula (II) is, for example, N-methylmorpholine N-oxide (NMO).

[0063] <<Compounds represented by general formula (III)>>

[0064]

[0065] In the formula, R 6 and R 7 These are, independently of each other, a hydrogen atom and a hydrocarbon group having 1 to 5 carbon atoms, which may be substituted with substituents, and the substituent is one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group, a phenoxy group, and an acyloxy group.

[0066] The aforementioned R 6 and R 7 The preferred number of carbon atoms in the hydrocarbon group and the specific compound are R of the general formula (I) mentioned above. 1 , R 2 , R 3 , and R 4 The number of carbon atoms is the same as that of the compound described.

[0067] Preferably, in general formula (III), from the viewpoint of the yield of aliphatic aldehyde, R 6 and R 7 These are, independently of each other, a hydrogen atom and a hydrocarbon group having 1 to 5 carbon atoms which may be substituted with a substituent, and the substituent is preferably one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group having 1 to 5 carbon atoms, a phenoxy group and an acyloxy group represented by the formula R-CO-O (wherein R is hydrogen or an alkyl group having 1 to 5 carbon atoms), and more preferably, in general formula (III), R 6and R 7 These are preferably a hydrogen atom or an unsubstituted hydrocarbon group having 1 to 5 carbon atoms, independently of each other, or more preferably, in general formula (III), R 6 and R 7 These are, independently of each other, a hydrogen atom, an unsubstituted hydrocarbon group having 1 to 3 carbon atoms which may be substituted with a substituent, or a hydrocarbon group having 1 to 3 carbon atoms which may be substituted with a substituent, wherein the substituent is preferably one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group having 1 to 3 carbon atoms, a phenoxy group, and an acyloxy group represented by the formula R-CO-O (wherein R is hydrogen or an alkyl group having 1 to 3 carbon atoms), and more preferably, in general formula (III), R 6 and R 7 These are preferably a hydrogen atom and an unsubstituted hydrocarbon group having 1 to 3 carbon atoms, independently of each other, and more preferably, in general formula (III), R 6 and R 7 Independently of each other, a hydrogen atom or a methyl group is more preferable.

[0068] Compounds represented by general formula (III) include, for example, AZADO (2-azadamantane-N-oxyl) and MAZADO (1-methyl-2-azadamantane-N-oxyl).

[0069] The molar ratio of the total N-oxyl compound and N-oxide compound to the ruthenium metal (total N-oxyl compound and N-oxide compound (mol) / ruthenium metal (mol)) is preferably 0.01 or higher, more preferably 0.05 or higher, and even more preferably 0.1 or higher from the viewpoint of aldehyde yield; preferably 20 or lower, more preferably 10 or lower, and even more preferably 5 or lower from the same viewpoint; preferably 0.01 to 20, more preferably 0.05 to 10, and even more preferably 0.1 to 5 from the same viewpoint.

[0070] In this process, the molar ratio of the total N-oxyl compound and the N-oxide compound to the aliphatic primary alcohol (total N-oxyl compound and N-oxide compound (mol) / aliphatic primary alcohol (mol)) is preferably 0.0001 or more, more preferably 0.001 or more, even more preferably 0.003 or more, preferably 0.5 or less, more preferably 0.2 or less, even more preferably 0.1 or less, preferably 0.0001 or more and 0.5 or less, more preferably 0.001 or more and 0.2 or less, even more preferably 0.003 or more and 0.1 or less.

[0071] <Phenol Derivatives> The oxidation step in the manufacturing method of the present invention is preferably carried out in the presence of a phenol derivative. The phenol derivative is preferably a compound represented by the following general formula (IV).

[0072]

[0073] In the formula, R 21 R is a hydrocarbon group, hydroxyl group, or alkoxy group which may contain one or more heteroatoms selected from the group consisting of oxygen atoms and nitrogen atoms, 22 R is a hydrogen atom or a linear or branched alkyl group. 23 and R 24 R is independently a hydrogen atom, a linear or branched alkyl group, or a cycloalkyl group which may be substituted with an alkyl group, or 23 The base is represented by equation (x), and R 24 However, R is a hydrogen atom, a linear or branched alkyl group, or a cycloalkyl group which may be substituted with an alkyl group, provided that R 23 and R 24 Except when both are hydrogen atoms.

[0074]

[0075] [In the formula, R 51 is R 21 This is the same definition as R 52 is R 22 This is the same definition as R54 is R 24 This is the same definition as above. * indicates the bonding position.

[0076] In the present invention, the R 21 The hydrocarbon group, which may contain one or more heteroatoms selected from the group consisting of oxygen and nitrogen atoms, preferably has 1 to 50 carbon atoms, more preferably 1 to 30 carbon atoms, more preferably 1 to 10 carbon atoms, and even more preferably 1 to 5 carbon atoms. The hydrocarbon group may be a linear or branched alkyl group, aryl group, alkylaryl group, arylalkyl group, or cycloalkyl group.

[0077] Hydrocarbon groups that may contain heteroatoms may include hydrocarbon groups containing heteroatoms by substituents such as ether groups, carbonyl groups, ester groups, hydroxyl groups, nitro groups, alkoxy groups, phenoxy groups, acyloxy groups, and triazine groups. Specifically, examples of hydrocarbon groups that may contain one or more heteroatoms selected from the group consisting of oxygen and nitrogen atoms are the groups represented by the following formulas (i) to (ix) (wherein * indicates the bond position).

[0078]

[0079]

[0080]

[0081]

[0082] The aforementioned R 21 The alkyl group is a linear or branched alkyl group, and the number of carbon atoms of the alkyl group is preferably 1 to 8, more preferably 1 to 5, and even more preferably 1 to 3. Specifically, examples include methyl group; ethyl group; n-propyl group, i-propyl group; n-butyl group, i-butyl group, sec-butyl group, t-butyl group, n-pentyl group, i-pentyl group, sec-pentyl group, t-pentyl group, 2-methylbutyl group, heptyl group, octyl group, and 2-ethylhexyl group.

[0083] The aforementioned R 21Examples of aryl groups include those with 6 to 10 carbon atoms, such as the phenyl group and the naphthyl group. Note that the term "naphthyl group" includes both 1-naphthyl and 2-naphthyl groups.

[0084] The aforementioned R 21 The alkylaryl group can be one in which the alkyl group is substituted on the aryl group, for example, a methylphenyl group, an ethylphenyl group, and so on.

[0085] The aforementioned R 21 The arylalkyl group can be one in which the aryl group is substituted for the alkyl group, for example, a benzyl group (phenylmethyl group), a phenethyl group (phenylethyl group), and so on.

[0086] The aforementioned R 21 Examples of alkoxy groups include alkoxy groups having 1 to 5 carbon atoms, preferably alkoxy groups having 1 to 3 carbon atoms. Examples of alkoxy groups having 1 to 5 carbon atoms include C1 alkyl groups such as methoxy groups; C2 alkoxy groups such as ethoxy groups; C3 alkoxy groups such as n-propyloxy groups and i-propyloxy groups; C4 alkoxy groups such as n-butoxy groups, i-butoxy groups, sec-butoxy groups, and t-butoxy groups; and C5 alkoxy groups such as n-pentyloxy groups, i-pentyloxy groups, sec-pentyloxy groups, t-pentyloxy groups, and 2-methylbutyloxy groups.

[0087] R 22 The group is a hydrogen atom or a linear or branched alkyl group, and the number of carbon atoms in the alkyl group is preferably 1 to 8, more preferably 1 to 5, and even more preferably 1 to 3. Specifically, examples include methyl group; ethyl group; n-propyl group, i-propyl group; n-butyl group, i-butyl group, sec-butyl group, t-butyl group; n-pentyl group, i-pentyl group, sec-pentyl group, t-pentyl group; 2-methylbutyl group; heptyl group; octyl group; and 2-ethylhexyl group.

[0088] R 23 and R 24These are, independently of each other, a hydrogen atom, a linear or branched alkyl group, or a cycloalkyl group which may be substituted with an alkyl group, or R 23 The base is represented by equation (x), and R 24 However, it is a hydrogen atom, a linear or branched alkyl group, or a cycloalkyl group which may be substituted with an alkyl group.

[0089] R 23 and R 24 The number of carbon atoms in the alkyl group is preferably 1 to 8, more preferably 1 to 5, and even more preferably 1 to 3. Specifically, the above-mentioned examples are available.

[0090] R 23 and R 24 The alkyl group of the cycloalkyl group, which may be substituted with an alkyl group, preferably has 1 to 8 carbon atoms, more preferably 1 to 5 carbon atoms, and even more preferably 1 to 3 carbon atoms. Specifically, the aforementioned examples are given.

[0091] R 23 and R 24 The cycloalkyl group preferably has 3 to 10 carbon atoms, more preferably 6 carbon atoms. Examples include a 3-carbon cycloalkyl group such as a cyclopropyl group; a 4-carbon cycloalkyl group such as a cyclobutyl group; a 5-carbon cycloalkyl group such as a cyclopentyl group; and a 6-carbon cycloalkyl group such as a cyclohexyl group.

[0092] R 23 and R 24 A specific example of a cycloalkyl group that may be substituted with an alkyl group is the 1-methylcyclohexyl group.

[0093] R 23 and R 24 The number of carbon atoms in the branched alkyl group is preferably 3 to 8, more preferably 3 to 5. Examples include i-propyl group; i-butyl group, sec-butyl group, t-butyl group; n-pentyl group; i-pentyl group, sec-pentyl group, t-pentyl group, 2-methylbutyl group.

[0094] R 23 and R 24 Preferably, at least one of these contains a branched alkyl group having 3 to 8 carbon atoms or a cycloalkyl group which may be substituted with an alkyl group, and more preferably contains a branched alkyl group having 3 to 8 carbon atoms.

[0095] Also, R 23 and R 24 At least one of them is a branched alkyl group having 3 to 8 carbon atoms, from the viewpoint of producing aliphatic aldehydes in good yield, and the other is preferably a hydrogen atom, R 3 and R 4 Both are preferably branched alkyl groups.

[0096] A preferred embodiment is one in which, from the viewpoint of producing an aliphatic aldehyde in general formula (IV) in good yield, R 21 R is an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms or a group represented by formula (iii), formula (iv), formula (v), formula (vi), formula (vii), formula (viiii), or formula (ix) (wherein * indicates the bond position), 22 R is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. 23 and R 24 R is independently a hydrogen atom, a branched alkyl group having 3 to 8 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms which may be substituted with an alkyl group, or 23 The group is represented by formula (ii) (where * indicates the bond position), and R 24 However, R is a hydrogen atom, a linear or branched alkyl group, or a cycloalkyl group which may be substituted with an alkyl group, provided that R 23 and R 24 It is preferable to exclude the case where both are hydrogen atoms, specifically CBP (2,2'-methylenebis[6-(1-methylcyclohexyl)-p-cresol]).

[0097]

[0098]

[0099]

[0100]

[0101] A more preferred embodiment is one in which, from the viewpoint of producing an aliphatic aldehyde in general formula (IV) in good yield, R 21 R is an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms. 22 is a hydrogen atom, R 23 and R 24 These are, independently of each other, a hydrogen atom and a branched alkyl group having 3 to 8 carbon atoms. However, R 23 and R 24 It is preferable to exclude the case where both are hydrogen atoms.

[0102] A more preferred embodiment is one in which, from the viewpoint of producing an aliphatic aldehyde in general formula (IV) in good yield, R 21 R is an alkyl group having 1 to 5 carbon atoms. 22 R is a hydrogen atom. 23 and R 24 These are branched alkyl groups having 3 to 8 carbon atoms, independently of each other.

[0103] More preferably, from the viewpoint of producing aliphatic aldehydes in general formula (IV) in good yield, R 21 R is a methyl group. 22 R is a hydrogen atom. 23 and R 24 It is even more preferable that it is a branched alkyl group having 4 carbon atoms.

[0104] Examples of compounds represented by general formula (IV) include the following:

[0105]

[0106] Compounds represented by general formula (IV) include, for example, compounds represented by the following formulas (V) or (VI).

[0107]

[0108] In formula (V), from the viewpoint of producing aliphatic aldehydes in good yield, R 32 and R 34R is a branched alkyl group, independently of each other. In formula (V), 32 and R 34 Preferably, the elements are branched alkyl groups having 3 to 8 carbon atoms, independently of each other.

[0109] Examples of compounds represented by general formula (V) include 2,5-di-tert-butylhydroquinone (DBH).

[0110]

[0111]

[0112] [In the formula, R 41 R is an alkoxy group. 43 It is a branched alkyl group.

[0113] In the above formula (VI), from the viewpoint of producing aliphatic aldehydes in good yield, R 41 R is an alkoxy group having 1 to 5 carbon atoms. 43 It is preferably a branched alkyl group having 3 to 8 carbon atoms, R 41 R is an alkoxy group having 1 to 3 carbon atoms. 43 It is more preferable that it is a branched alkyl group having 3 to 6 carbon atoms.

[0114] Compounds represented by general formula (VI) include, for example, 3-tert-butyl-4-hydroxyanisole (BHA).

[0115]

[0116] In this process, the molar ratio of the phenol derivative to the ruthenium metal (phenol derivative (mol) / ruthenium metal (mol)) is preferably 0.7 or more, more preferably 0.9 or more, even more preferably 1.5 or more, preferably 10 or less, more preferably 5 or less, and even more preferably 3 or less, from the viewpoint of aldehyde yield. The molar ratio of the phenol derivative to the metal (phenol derivative (mol) / metal (mol)) is preferably 0.7 or more and 10 or less, more preferably 0.9 or more and 5 or less, and even more preferably 1.5 or more and 3 or less, from the viewpoint of aldehyde yield.

[0117] In this step, the molar ratio of the phenol derivative to the aliphatic primary alcohol (phenol derivative (mol) / aliphatic primary alcohol (mol)) is preferably 0.005 or more, more preferably 0.01 or more, even more preferably 0.03 or more, preferably 3 or less, more preferably 1 or less, and even more preferably 0.3 or less, from the viewpoint of aldehyde yield. The molar ratio of the phenol derivative to the aliphatic primary alcohol (phenol derivative (mol) / aliphatic primary alcohol (mol)) is preferably 0.005 or more and 3 or less, more preferably 0.01 or more and 1 or less, and even more preferably 0.03 or more and 0.3 or less, from the viewpoint of aldehyde yield.

[0118] The present invention includes the following aspects: [1] A method for producing an aliphatic aldehyde, comprising the step of oxidizing an aliphatic primary alcohol having 4 or more carbon atoms with molecular oxygen in the presence of a ruthenium-supported catalyst, wherein the ruthenium-supported catalyst comprises ruthenium supported on a carrier, the carrier is a porous oxide, and the surface area per unit mass of ruthenium is 60 m². 2 A method for producing an aliphatic aldehyde, wherein the amount is 0.15 mL / g or more, and the mesopore volume of the ruthenium-supported catalyst is 0.15 mL / g or more.

[0119] [2] The surface area per unit mass of ruthenium is 60 m 2 / g or more 250m 2 The manufacturing method according to [1], wherein the amount is less than or equal to / g.

[0120] [3] The surface area per unit mass of ruthenium is 65 m 2 / g or more 250m 2 The manufacturing method according to [1] or [2], wherein the amount is less than or equal to / g.

[0121] [4] The surface area per unit mass of ruthenium is preferably 70 m 2 / g or more 200m 2 A manufacturing method according to any one of [1] to [3], wherein the amount is less than or equal to / g.

[0122] [5] The surface area per unit mass of ruthenium is 70 m 2 / g or more 190m 2 A manufacturing method according to any one of [1] to [4], wherein the amount is less than or equal to / g.

[0123] [6] The surface area per unit mass of ruthenium is 70 m 2 / g or more 180m 2 A manufacturing method according to any one of [1] to [5], wherein the amount is less than or equal to / g.

[0124] [7] The surface area per unit mass of ruthenium is 70 m 2 / g or more 170m 2 A manufacturing method according to any one of [1] to [6], wherein the amount is less than or equal to / g.

[0125] [8] The surface area per unit mass of ruthenium is 100 m 2 / g or more 170m 2 A manufacturing method according to any one of [1] to [7], wherein the amount is less than or equal to / g.

[0126] [9] The surface area per unit mass of ruthenium is 130 m 2 / g or more 160m 2 A manufacturing method according to any one of [1] to [8], wherein the amount is less than or equal to / g.

[0127]

[10] The manufacturing method according to any one of [1] to [9], wherein the particle size of the ruthenium is 1 nm or more and 20 nm or less.

[0128]

[11] The manufacturing method according to any one of [1] to

[10] , wherein the particle size of the ruthenium is 2 nm or more and 10 nm or less.

[0129]

[12] The manufacturing method according to any one of [1] to

[11] , wherein the particle size of the ruthenium is 2.5 nm or more and 5 nm or less.

[0130]

[13] The manufacturing method according to any one of [1] to

[12] , wherein the mesopore volume of the ruthenium-supported catalyst is 0.15 mL / g or more and 0.5 mL / g or less.

[0131]

[14] The manufacturing method according to any one of [1] to

[13] , wherein the mesopore volume of the ruthenium-supported catalyst is 0.2 mL / g or more and 0.5 mL / g or less.

[0132]

[15] The manufacturing method according to any one of [1] to

[14] , wherein the mesopore volume of the ruthenium-supported catalyst is 0.25 mL / g or more and 0.5 mL / g or less.

[0133]

[16] The manufacturing method according to any one of [1] to

[15] , wherein the mesopore volume of the ruthenium-supported catalyst is 0.25 mL / g or more and 0.45 mL / g or less.

[0134]

[17] The manufacturing method according to any one of [1] to

[16] , wherein the mesopore volume of the ruthenium-supported catalyst is 0.25 mL / g or more and 0.4 mL / g or less.

[0135]

[18] The manufacturing method according to any one of [1] to

[17] , wherein the ruthenium metal content in the ruthenium-supported catalyst is preferably 1% by mass or more and 50% by mass or less, more preferably 1% by mass or more and 30% by mass or less, even more preferably 1% by mass or more and 10% by mass or less, even more preferably 1% by mass or more and less than 10% by mass, even more preferably 3% by mass or more and 30% by mass or less, even more preferably 3% by mass or more and 10% by mass or less, even more preferably 5% by mass or more and less than 10% by mass.

[0136]

[19] The manufacturing method according to any one of [1] to

[18] , wherein the number of carbon atoms in the aliphatic primary alcohol is preferably 4 to 30, more preferably 6 to 22, even more preferably 6 to 14, even more preferably 8 to 14, even more preferably 10 to 14, even more preferably 8 to 12, and even more preferably 12.

[0137]

[20] The method of production according to any one of [1] to

[19] , wherein the aliphatic primary alcohol is an aliphatic linear saturated primary alcohol, preferably an aliphatic linear saturated primary alcohol having 8 or more carbon atoms and 14 or fewer carbon atoms.

[0138]

[21] The manufacturing method according to any one of [1] to

[20] , wherein the porous oxide is one or more selected from the group consisting of alumina, titania, zirconia, silica, silicaalumina, magnesia, zeolite, and activated carbon.

[0139]

[22] The manufacturing method according to any one of [1] to

[21] , wherein the porous oxide is preferably alumina, activated carbon, titania, silica alumina, or zeolite, and more preferably alumina or activated carbon.

[0140]

[23] The manufacturing method according to [1] to

[22] , wherein the ratio of ruthenium ( mmol) to aliphatic primary alcohol ( mmol) having 4 or more carbon atoms [ruthenium ( mmol) / aliphatic primary alcohol ( mmol) having 4 or more carbon atoms] is preferably 0.001 or more and 0.2 or less, more preferably 0.001 or more and 0.1 or less, even more preferably 0.001 or more and 0.05 or less, even more preferably 0.001 or more and 0.045 or less, even more preferably 0.005 or more and 0.05 or less, even more preferably 0.005 or more and 0.045 or less, even more preferably 0.01 or more and 0.045 or less.

[0141]

[24] The manufacturing method according to any one of [1] to

[23] , wherein the temperature of the oxidation step is preferably 60°C or more and 200°C or less, more preferably 70°C or more and 180°C or less, and even more preferably 80°C or more and 170°C or less.

[0142]

[25] A manufacturing method according to any one of [1] to

[24] , wherein the oxidation step is carried out in the presence of a solvent.

[0143]

[26] The manufacturing method according to

[25] , wherein the ratio of ruthenium (molecular) to aliphatic primary alcohol (molecular) having 4 or more carbon atoms [ruthenium (molecular) / aliphatic primary alcohol (molecular) having 4 or more carbon atoms] is preferably 0.001 or more and 0.5 or less, preferably 0.001 or more and 0.2 or less, more preferably 0.005 or more and 0.1 or less, more preferably 0.005 or more and 0.05 or less, more preferably 0.005 or more and 0.045 or less, more preferably 0.01 or more and 0.045 or less.

[0144]

[27] The initial activity value of the aldehyde (per unit time and unit amount of catalyst) is preferably 2 mmol / g / hr or more and 10 mmol / g / hr or less, more preferably 3 mmol / g / hr or more and 10 mmol / g / hr or less, and even more preferably 4 mmol / g / hr or more and 10 mmol / g / hr or less, according to any one of [1] to

[26] .

[0145]

[28] The manufacturing method according to any one of [1] to

[27] , wherein the oxidation step is further carried out in the presence of one or more N-oxyl compounds and / or N-oxide compounds selected from the group consisting of a compound represented by the following general formula (I), a compound represented by the following general formula (II), and a compound represented by the following general formula (III).

[0146]

[0147] [In the formula, R 1 , R 2 , R 3 , and R 4R is a hydrocarbon group having 1 to 5 carbon atoms, which may be substituted with a hydrogen atom or a substituent, and the substituent is one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group, a phenoxy group and an acyloxy group, 5 [This is an oxygen atom or a methylene group.]

[0148]

[0149] [In the formula, R 11 , R 12 , R 13 , and R 14 R is a hydrocarbon group having 1 to 5 carbon atoms, which may be substituted with a hydrogen atom or a substituent, and the substituent is one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group, a phenoxy group and an acyloxy group. 15 [This is an oxygen atom or a methylene group.]

[0150]

[0151] [In the formula, R 6 , and R 7 These are, independently of each other, a hydrogen atom, an unsubstituted hydrocarbon group having 1 to 5 carbon atoms, or a hydrocarbon group having 1 to 5 carbon atoms that may be substituted with a substituent, and the substituent is one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group, a phenoxy group, and an acyloxy group.

[0152]

[29] The method for producing the product according to

[28] , wherein the N-oxyl compound and / or N-oxide compound is one or more selected from the group consisting of 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO), 1-methyl-2-azaadamantane-N-oxyl (MAZADO), 2-azaadamantane-N-oxyl (AZADO), and N-methylmorpholine (NMO).

[0153]

[30] The manufacturing method according to

[28] or

[29] , wherein the molar ratio of the total of the N-oxyl compound and the N-oxide compound to the ruthenium metal (total of N-oxyl compound and N-oxide compound (mol) / ruthenium metal (mol)) is 0.01 or more and 20 or less.

[0154]

[31] The manufacturing method according to any one of

[28] to

[30] , wherein the molar ratio of the total of the N-oxyl compound and the N-oxide compound to the ruthenium metal (total of N-oxyl compound and N-oxide compound (mol) / ruthenium metal (mol)) is 0.05 or more and 10 or less.

[0155]

[32] The manufacturing method according to any one of

[28] to

[31] , wherein the molar ratio of the total N-oxyl compound and the N-oxide compound to the ruthenium metal (total N-oxyl compound and N-oxide compound (mol) / the metal (mol)) is 0.1 or more and 5 or less.

[0156]

[33] The manufacturing method according to any one of

[28] to

[32] , wherein the molar ratio of the total N-oxyl compound and the N-oxide compound to the aliphatic primary alcohol (total N-oxyl compound and N-oxide compound (mol) / aliphatic primary alcohol (mol)) is 0.0001 or more and 0.5 or less.

[0157]

[34] The manufacturing method according to any one of

[28] to

[33] , wherein the molar ratio of the total N-oxyl compound and N-oxide compound to the aliphatic primary alcohol (total N-oxyl compound and N-oxide compound (mol) / aliphatic primary alcohol (mol)) is 0.001 or more and 0.2 or less.

[0158]

[35] The manufacturing method according to any one of

[28] to

[34] , wherein the molar ratio of the total N-oxyl compound and the N-oxide compound to the aliphatic primary alcohol (total N-oxyl compound and N-oxide compound (mol) / aliphatic primary alcohol (mol)) is 0.003 or more and 0.1 or less.

[0159]

[36] A method for producing an aliphatic aldehyde according to any one of [1] to

[27] , wherein the oxidation step is further carried out in the presence of a phenol derivative which is a compound represented by the following general formula (IV).

[0160]

[0161] In the formula, R 21 R is a hydrocarbon group, hydroxyl group, or alkoxy group which may contain one or more heteroatoms selected from the group consisting of oxygen atoms and nitrogen atoms, 22 R is a hydrogen atom or a linear or branched alkyl group. 23 and R 24 R is independently a hydrogen atom, a linear or branched alkyl group, or a cycloalkyl group which may be substituted with an alkyl group, or 23 The base is represented by equation (x), and R 4 However, R is a hydrogen atom, a linear or branched alkyl group, or a cycloalkyl group which may be substituted with an alkyl group, provided that R 23 and R 24 Except when both are hydrogen atoms.

[0162]

[0163] [In the formula, R 51 is R 21 This is the same definition as R 52 is R 22 This is the same definition as R 54 is R 24 This is the same definition as [the previous definition]. In the formula, * indicates the bonding position.

[0164]

[37] In the formula, R 23 and R 24 The manufacturing method according to

[36] , wherein at least one of the comprises a branched alkyl group having 3 to 8 carbon atoms.

[0165]

[38] The method for producing the compound according to

[36] or

[37] , wherein the compound represented by the general formula (IV) is one or more selected from the group consisting of dibutylhydroxytoluene (BHT), 2,2'-methylenebis[6-(1-methylcyclohexyl)-p-cresol] (CBP), pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (AO-60), 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro[5.5]undecane (AO-80), and 3-tert-butyl-4-hydroxyanisole (BHA).

[0166]

[39] The manufacturing method according to

[36] or

[37] , wherein the molar ratio of the phenol derivative to the metal (phenol derivative (mol) / metal (mol)) is 0.7 or more and 10 or less.

[0167]

[40] The manufacturing method according to any one of

[36] to

[39] , wherein the molar ratio of the phenol derivative to the metal (phenol derivative (mol) / metal (mol)) is 0.9 or more and 5 or less.

[0168]

[41] The manufacturing method according to any one of

[36] to

[40] , wherein the molar ratio of the phenol derivative to the metal (phenol derivative (mol) / metal (mol)) is 1.5 or more and 3 or less.

[0169]

[42] The manufacturing method according to any one of

[36] to

[41] , wherein the molar ratio of the phenol derivative to the aliphatic primary alcohol (phenol derivative (mol) / aliphatic primary alcohol (mol)) is 0.005 or more and 3 or less.

[0170]

[43] The manufacturing method according to any one of

[36] to

[42] , wherein the molar ratio of the phenol derivative to the aliphatic primary alcohol (phenol derivative (mol) / aliphatic primary alcohol (mol)) is 0.01 or more and 1 or less.

[0171]

[44] The manufacturing method according to any one of

[36] to

[43] , wherein the molar ratio of the phenol derivative to the aliphatic primary alcohol (phenol derivative (mol) / aliphatic primary alcohol (mol)) is 0.03 or more and 0.3 or less.

[0172] The present invention will be described in more detail below with reference to examples. In the following examples, the measurement and evaluation of each physical property was performed by the following methods.

[0173] <Method for measuring the surface area per unit mass and particle size of ruthenium> The surface area per unit mass of ruthenium was measured using the CO pulse method with a BELCAT-B manufactured by Nippon Bell. For pretreatment before measurement, helium gas was passed through the sample (catalyst) for 15 minutes at 200°C, followed by hydrogen gas for 15 minutes to reduce the active metal species (ruthenium). The measurement was performed using 10% CO / He gas under conditions of 50°C with pulse measurements, and the surface area of ​​the active metal species was calculated based on the number of moles of CO adsorbed on the active metal species until equilibrium was reached. The stoichiometric ratio of the active metal species to CO was set to 1.

[0174] Using the obtained surface area per unit mass of ruthenium, the particle size of the active metal species (ruthenium) was calculated using the following formula based on the ratio of the volume (assuming the sample particles are perfectly spherical) to the surface area per unit mass of ruthenium. The density when ruthenium is used as the active metal species is 12.410 g / cm³. 3 That is the case.

[0175]

[0176] In the formula, X is the density (g / cm³) of ruthenium (an active metal species). 3 ) and Y is the surface area per unit mass of ruthenium (m 2 It is / g).

[0177] <Method for Measuring Mesopore Volume of Catalysts> The mesopore volume of the catalyst was measured by mercury intrusion porositometry in accordance with ASTM standard ASTM D4284-83 (Standard method for measuring pore volume distribution of catalysts by mercury intrusion porositometry). Specifically, the mercury intrusion method was performed using an AutoPore IV manufactured by Micromeritrics. The measurement pressure was 1.5 to 60,000 psi, and the equilibrium time was 5 seconds. The mesopore volume of the catalyst is defined as the cumulative volume of mercury introduced at pressures between 30 MPa and 400 MPa, and corresponds to the volume contained in pores with apparent diameters between 2 and 50 nm.

[0178] <Gas Chromatography Equipment and Analytical Conditions> GC System: Agilent Technologies, Inc. 7890B, Flame Ionization Detector

[0179] Column: DB-1 (capillary column, 100% dimethylpolysiloxane, inner diameter 0.25 mm, length 30 m, film thickness 0.25 μm, manufactured by Agilent Technologies, Inc.) was used. Carrier gas: Nitrogen, 1.5 mL / min Injection conditions: 280°C, split ratio 100 / 1 Injection volume: 1 μL Detection conditions: FID method, 280°C Column temperature conditions: Starting at 100°C, held at 100°C for 2 minutes, then heated to 180°C at a rate of 8°C / min, and then heated to 280°C at a rate of 10°C / min. After that, held at 280°C for 5 minutes.

[0180] [Examples and Comparative Examples] In the following examples and comparative examples, "%" refers to "mass%" unless otherwise specified. The following raw materials were used in the reaction. Octanol: Manufactured by Kao Corporation, Toluene: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., Wako Special Grade, Tetradecane: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., Wako Special Grade, Diethyl ether: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., Wako Special Grade, TEMPO: 2,2,6,6-tetramethylpiperidine N-oxyl, Manufactured by Fujifilm Wako Pure Chemical Industries, Wako Special Grade, MAZADO: 1-methyl-2-azadamantane-N-oxyl, Manufactured by Fujifilm Wako Pure Chemical Industries, Wako Special Grade, AZADO: 2-azadamantane-N-oxyl, Manufactured by Fujifilm Wako Pure Chemical Industries, Wako Special Grade, NMO: N-methylmorpholine N-oxide, Manufactured by Fujifilm Wako Pure Chemical Industries, Wako Special Grade, BHT: Dibutylhydroxytoluene (Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., Wako Special Grade) CBP: 2,2'-methylenebis[6-(1-methylcyclohexyl)-p-cresol] (manufactured by Tokyo Chemical Industry Co., Ltd., reagent grade), AO-60: pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (manufactured by ADEKA Corporation, product name "ADEKA Stab AO-60"), AO-80: 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro[5.5]undecane (manufactured by ADEKA Corporation, product name "ADEKA Stab AO-80"), BHA: 3-tert-butyl-4-hydroxyanisole (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., Wako Special Grade)

[0181] [Example 1] In a glass reaction tube with an inner diameter of 34 mm, a 5% alumina-supported ruthenium catalyst (manufactured by N.E. Chemcat, HYAc-5E, S type, surface area per unit mass of ruthenium 73.1 m²) was used as the catalyst. 2Ruthenium (particle size 6.6 nm, mesopore volume 0.31 mL / g, dry mass 0.10 g), 1-octanol (0.26 g, 2.0 mmol, ruthenium / 1-octanol molar ratio 0.025), toluene (solvent, 4.0 mL, 3.47 g), and tetradecane (GC internal standard, 0.026 g) were added. An oxygen-filled balloon was connected to the reaction tube to purge the reaction tube with oxygen, and the mixture in the reaction tube was stirred at 90°C for 2 hours. After that, the reaction tube was cooled to 30°C to terminate the reaction.

[0182] The reaction results were obtained by quantitatively analyzing each component of the reaction solution, collected 2 hours after the start of heating and stirring, using gas chromatography (GC) and the internal standard method. Using the amounts of each component obtained in the reactant, the initial aldehyde activity (2h), aldehyde yield (2h), and carboxylic acid production rate (2h) were calculated according to the following formula. Tetradecane was used as the internal standard, and diethyl ether was used as the solvent. The obtained initial aldehyde activity, aldehyde yield, and carboxylic acid production rate (by-product) are shown in Table 1 below.

[0183] Specifically, 0.2 mL of the reaction solution was sampled, and the catalyst was removed by filtering the solution through a membrane filter (polytetrafluoroethylene (PTFE), 0.2 μm). The resulting filtrate was taken into a screw tube containing 2 mL of diethyl ether, diluted, and then subjected to GC analysis.

[0184] <Method for Calculating Aldehyde Initial Activity (2h)> The aldehyde initial activity was calculated using the mass of octanal in the reaction solution obtained by GC analysis of the reaction solution collected 2 hours after the start of heating and stirring, according to the following formula. A higher aldehyde initial activity value indicates better initial activity.

[0185]

[0186] <Method for measuring aldehyde yield (2h)> The aldehyde yield (2h) was calculated using the mass of octanal in the reaction solution obtained by GC analysis of the reaction solution collected 2 hours after the start of heating and stirring, according to the following formula. A higher aldehyde yield value indicates a better yield.

[0187]

[0188] <Method for measuring carboxylic acid production rate (2h)> The carboxylic acid production rate (2h) was calculated using the mass of octanoic acid in the reaction solution obtained by GC analysis of the reaction solution collected 2 hours after the start of heating and stirring, according to the following formula. A smaller carboxylic acid production rate indicates better suppression of carboxylic acid production.

[0189]

[0190] [Example 2] As a catalyst, a 5% alumina-supported ruthenium catalyst (manufactured by N.E. Chemcat, HYAc-5E, S type, surface area per unit mass of ruthenium 73.1 m²) 2 Instead of ruthenium particle size 6.6 nm, mesopore volume 0.31 mL / g, dry mass 0.10 g), a 5% alumina-supported ruthenium catalyst (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., surface area per unit mass of ruthenium 142.1 m²) is used. 2 The procedure was carried out in the same manner as in Example 1, except that a ruthenium particle size of 3.4 nm, a mesopore volume of 0.28 mL / g, and a dry mass of 0.10 g were used.

[0191] [Example 3] 5% alumina-supported ruthenium catalyst (manufactured by N.E. Chemcat, HYAc-5E, S type, surface area per unit mass of ruthenium 73.1 m²) 2 Instead of ruthenium particle size 6.6 nm, mesopore volume 0.31 mL / g, dry mass 0.10 g), a 5% activated carbon-supported ruthenium catalyst (manufactured by N.E. Chemcat, type A, surface area per unit mass of ruthenium 145.7 m²) is used. 2 The procedure was carried out in the same manner as in Example 1, except that a ruthenium particle size of 3.3 nm, a mesopore volume of 0.31 mL / g, and a dry mass of 0.10 g were used.

[0192] [Example 4] A 5% alumina-supported ruthenium catalyst was used (manufactured by N.E. Chemcat, HYAc-5E, S type, with a surface area of ​​73.1 m² per unit mass of ruthenium). 2Instead of ruthenium particle size 6.6 nm, mesopore volume 0.31 mL / g, dry mass 0.10 g), a 5% alumina-supported ruthenium catalyst (manufactured by N.E. Chemcat, HYAc-5E, N-type, surface area per unit mass of ruthenium 154 m²) was used. 2 The procedure was carried out in the same manner as in Example 1, except that a ruthenium particle size of 3.1 nm, a mesopore volume of 0.30 mL / g, and a dry mass of 0.10 g were used.

[0193] [Example 5] 5% alumina-supported ruthenium catalyst (manufactured by N.E. Chemcat, HYAc-5E, S type, surface area per unit mass of ruthenium 73.1 m²) 2 Instead of using a 5% activated carbon-supported ruthenium catalyst (Johnson Matthey, Type 600, surface area per unit mass of ruthenium 197.3 m²) (ruthenium particle size 6.6 nm, mesopore volume 0.31 mL / g, dry mass 0.10 g), use a 5% activated carbon-supported ruthenium catalyst (Johnson Matthey, Type 600, surface area per unit mass of ruthenium 197.3 m²). 2 The procedure was carried out in the same manner as in Example 1, except that (a ruthenium particle size of 2.5 nm, mesopore volume of 0.24 mL / g, and dry mass of 0.10 g) was used.

[0194] [Comparative Example 1] A 5% alumina-supported ruthenium catalyst was used as the catalyst (manufactured by N.E. Chemcat, HYAc-5E, S type, with a surface area of ​​73.1 m² per unit mass of ruthenium). 2 The procedure was carried out in the same manner as in Example 1, except that a 5% alumina-supported palladium catalyst (manufactured by Tokyo Chemical Industry Co., Ltd., dry mass 0.10 g) was used instead of ruthenium (particle size 6.6 nm, mesopore volume 0.31 mL / g, dry mass 0.10 g).

[0195] [Comparative Example 2] A 5% alumina-supported ruthenium catalyst was used (manufactured by N.E. Chemcat, HYAc-5E, S type, with a surface area of ​​73.1 m² per unit mass of ruthenium). 2 The procedure was carried out in the same manner as in Example 1, except that a 5% activated carbon-supported palladium catalyst (Johnson Matthey, Type 39, dry mass 0.10 g) was used instead of ruthenium (particle size 6.6 nm, mesopore volume 0.31 mL / g, dry mass 0.10 g).

[0196] [Comparative Example 3] A 5% alumina-supported ruthenium catalyst was used as the catalyst (manufactured by N.E. Chemcat, HYAc-5E, S type, with a surface area of ​​73.1 m² per unit mass of ruthenium). 2 The procedure was carried out in the same manner as in Example 1, except that a 5% activated carbon-supported rhodium catalyst (Kawasaki Fine Chemicals, Type K, dry mass 0.10 g) was used instead of ruthenium (particle size 6.6 nm, mesopore volume 0.31 mL / g, dry mass 0.10 g).

[0197] [Comparative Example 4] A 5% alumina-supported ruthenium catalyst was used (manufactured by N.E. Chemcat, HYAc-5E, S type, with a surface area of ​​73.1 m² per unit mass of ruthenium). 2 Instead of ruthenium particle size 6.6 nm, mesopore volume 0.31 mL / g, dry mass 0.10 g), a 5% activated carbon-supported ruthenium catalyst (manufactured by Kawaken Fine Chemicals, type SD, surface area of ​​ruthenium per unit mass 44.3 m²) is used. 2 The procedure was carried out in the same manner as in Example 1, except that (a ruthenium particle size of 10.9 nm, a mesopore volume of 0.17 mL / g, and a dry mass of 0.10 g) was used.

[0198] Table 1 below shows the initial aldehyde activity, aldehyde yield, and carboxylic acid production rate obtained for Examples 1 to 5 and Comparative Examples 1 to 4.

[0199]

[0200] As shown in Table 1, it was confirmed that the method of the present invention can efficiently produce aliphatic aldehydes by oxidizing aliphatic primary alcohols having 4 or more carbon atoms in a short time. Furthermore, it was confirmed that the method of the present invention can produce aliphatic aldehydes by oxidizing aliphatic primary alcohols having 4 or more carbon atoms while suppressing the formation of carboxylic acids.

[0201] [Example 11] In a glass reaction tube with an inner diameter of 34 mm, a 5% alumina-supported ruthenium catalyst (manufactured by N.E. Chemcat, HYAc-5E, N-type, surface area per unit mass of ruthenium 154 m²) was used as the catalyst. 2The following were added: ruthenium (particle size 3.1 nm, mesopore volume 0.30 mL / g, dry mass 0.10 g), TEMPO (2,2,6,6-tetramethylpiperidine N-oxyl) (0.023 g, 0.15 mmol), 1-octanol (0.26 g, 2.0 mmol), toluene (4.0 mL, 3.47 g), and tetradecane (GC internal standard, 0.026 g). An oxygen-filled balloon was connected to the reaction tube to purge the reaction tube with oxygen, and the mixture in the reaction tube was stirred at 90°C for 24 hours. After that, the reaction tube was cooled to 30°C to terminate the reaction.

[0202] The reaction results were obtained by quantitatively analyzing each component using the internal standard method with reaction solutions collected 2 hours and 24 hours after the start of heating and stirring, respectively, using gas chromatography (GC). Using the amounts of each component obtained in the reactant, the initial aldehyde activity (2h) and aldehyde yield (2h, 24h) were calculated according to the following formula. Tetradecane was used as the internal standard, and diethyl ether was used as the solvent. The obtained initial aldehyde activity, aldehyde yield, and the rate of carboxylic acid production as a by-product are shown in Table 2 below.

[0203] Specifically, 0.2 mL of the reaction solution was sampled, and the catalyst was removed by filtering the solution through a membrane filter (polytetrafluoroethylene (PTFE), 0.2 μm). The resulting filtrate was taken into a screw tube containing 2 mL of diethyl ether, diluted, and then subjected to GC analysis.

[0204] <Method for calculating aldehyde initial activity (2h)> The aldehyde initial activity is as described above.

[0205] <Method for measuring aldehyde yield (2h)> The aldehyde yield (2h) is as described above.

[0206] <Method for calculating alcohol conversion rate (24h)> The alcohol conversion rate (24h) was calculated using the mass of octanal in the reaction solution obtained by GC analysis of the reaction solution collected 24 hours after the start of heating and stirring, according to the following formula.

[0207]

[0208] <Method for measuring carboxylic acid production rate (24h)> The carboxylic acid production rate (24h) was calculated using the mass of octanoic acid in the reaction solution obtained by GC analysis of the reaction solution collected 24 hours after the start of heating and stirring, according to the following formula. A smaller carboxylic acid production rate indicates better suppression of carboxylic acid production.

[0209]

[0210] <Method for measuring aldehyde yield (24 h)> The aldehyde yield (24 h) was calculated using the mass of octanal in the reaction solution obtained by GC analysis of the reaction solution collected 24 hours after the start of heating and stirring, according to the following formula. A higher aldehyde yield value indicates a better yield.

[0211]

[0212] <Method for measuring aldehyde selectivity (24h)> The aldehyde selectivity (24h) was calculated using the aldehyde yield and alcohol conversion rate after 24 hours, which were obtained from the reaction solution obtained by GC analysis of the reaction solution collected 24 hours after the start of heating and stirring, according to the following formula.

[0213]

[0214] [Examples 12-16] The procedure was the same as in Example 11, except that the amount of TEMPO (2,2,6,6-tetramethylpiperidine N-oxyl) was changed to the amount shown in Table 1.

[0215] [Examples 17-19] The procedure was the same as in Example 13, except that the N-oxyl compounds shown in Table 2 were used instead of TEMPO (2,2,6,6-tetramethylpiperidine N-oxyl).

[0216] [Example 20] A 5% alumina-supported ruthenium catalyst was used as the catalyst (manufactured by N.E. Chemcat, HYAc-5E, N-type, surface area per unit mass of ruthenium: 154 m²). 2 Instead of using a 5% activated carbon-supported ruthenium catalyst (Johnson Matthey, Type 600, surface area per unit mass of ruthenium 197.3 m²) (ruthenium particle size 3.1 nm, mesopore volume 0.30 mL / g, dry mass 0.10 g),2 The procedure was carried out in the same manner as in Example 13, except that (a ruthenium particle size of 2.5 nm, a mesopore volume of 0.24 mL / g, and a dry mass of 0.10 g) was used.

[0217] [Comparative Example 5] A 5% alumina-supported ruthenium catalyst was used as the catalyst (manufactured by N.E. Chemcat, HYAc-5E, N-type, with a surface area of ​​154 m² per unit mass of ruthenium). 2 Instead of ruthenium particle size 3.1 nm, mesopore volume 0.30 mL / g, dry mass 0.10 g), use a 5% activated carbon-supported ruthenium catalyst (manufactured by Kawaken Fine Chemicals, type SD, surface area per unit mass of ruthenium 44.3 m²). 2 The procedure was carried out in the same manner as in Example 13, except that a ruthenium particle size of 10.9 nm, a mesopore volume of 0.17 mL / g, and a dry mass of 0.10 g were used.

[0218]

[0219] As shown in Table 2, it was confirmed that the method of the present invention, which further includes an N-oxyl compound in the oxidation step, can produce aliphatic aldehydes in good yield by oxidizing aliphatic primary alcohols having 4 or more carbon atoms.

[0220] Furthermore, in the ruthenium-supported alumina catalyst, the aliphatic aldehyde yield after 24 hours was significantly higher than the aliphatic aldehyde yield after 2 hours.

[0221] Furthermore, it was found that the reaction using a ruthenium-supported alumina catalyst and an N-oxyl compound exhibited high aldehyde selectivity.

[0222] [Example 21] In a glass reaction tube with an inner diameter of 34 mm, a 5% alumina-supported ruthenium catalyst (manufactured by N.E. Chemcat, HYAc-5E, N-type, surface area per unit mass of ruthenium 154 m²) was used as the catalyst. 2The following were added: ruthenium (particle size 3.1 nm, mesopore volume 0.30 mL / g, dry mass 0.10 g), BHT (dibutylhydroxytoluene) (0.022 g, 0.2 mmol), 1-octanol (0.26 g, 2.0 mmol), toluene (4.0 mL, 3.47 g), and tetradecane (GC internal standard, 0.026 g). An oxygen-filled balloon was connected to the reaction tube to purge the reaction tube with oxygen, and the mixture in the reaction tube was stirred at 90°C for 24 hours. After that, the reaction tube was cooled to 30°C to terminate the reaction.

[0223] The reaction results were obtained by quantitatively analyzing each component using the internal standard method with reaction solutions collected 2 hours and 24 hours after the start of heating and stirring, respectively, using gas chromatography (GC). Using the amounts of each component obtained in the reactant, the initial aldehyde activity (2h) and aldehyde yield (2h, 24h) were calculated according to the following formula. Tetradecane was used as the internal standard, and diethyl ether was used as the solvent. The obtained initial aldehyde activity, aldehyde yield, and the rate of carboxylic acid production as a by-product are shown in Table 3 below.

[0224] Specifically, 0.2 mL of the reaction solution was sampled, and the catalyst was removed by filtering the solution through a membrane filter (polytetrafluoroethylene (PTFE), 0.2 μm). The resulting filtrate was taken into a screw tube containing 2 mL of diethyl ether, diluted, and then subjected to GC analysis.

[0225] [Examples 22-24] The procedure was the same as in Example 21, except that the amount of BHT (dibutylhydroxytoluene) was changed to the amount shown in Table 1.

[0226] [Examples 25-29] The procedure was the same as in Example 22, except that the phenol derivatives shown in Table 3 were used instead of BHT (dibutylhydroxytoluene).

[0227] [Example 30] A 5% alumina-supported ruthenium catalyst was used as the catalyst (manufactured by N.E. Chemcat, HYAc-5E, N-type, surface area per unit mass of ruthenium: 154 m²). 2Instead of using a 5% activated carbon-supported ruthenium catalyst (Johnson Matthey, Type 600, surface area per unit mass of ruthenium 197.3 m²) (ruthenium particle size 3.1 nm, mesopore volume 0.30 mL / g, dry mass 0.10 g), 2 The procedure was carried out in the same manner as in Example 22, except that (a ruthenium particle size of 2.5 nm, a mesopore volume of 0.24 mL / g, and a dry mass of 0.10 g) was used.

[0228] [Comparative Example 6] A 5% alumina-supported ruthenium catalyst was used as the catalyst (manufactured by N.E. Chemcat, HYAc-5E, N-type, with a surface area of ​​154 m² per unit mass of ruthenium). 2 Instead of ruthenium particle size 3.1 nm, mesopore volume 0.30 mL / g, dry mass 0.10 g), use a 5% activated carbon-supported ruthenium catalyst (manufactured by Kawaken Fine Chemicals, type SD, surface area per unit mass of ruthenium 44.3 m²). 2 The procedure was carried out in the same manner as in Example 22, except that (a ruthenium particle size of 10.9 nm, a mesopore volume of 0.17 mL / g, and a dry mass of 0.10 g) was used.

[0229] Tables 2 and 3 show the initial aldehyde activity, aldehyde yield, and carboxylic acid production rate obtained for Examples 11 to 30 and Comparative Examples 5 and 6. Specifically, Table 3 shows the type of metal-supported catalyst used (catalyst species, support, model number, manufacturer), the amount of metal-supported catalyst, additives, and results.

[0230]

[0231] As shown in Table 3, it was confirmed that the method of the present invention, which further includes a phenol derivative in the oxidation step, can produce aliphatic aldehydes in good yield by oxidizing aliphatic primary alcohols having 4 or more carbon atoms.

[0232] Furthermore, in the ruthenium-supported alumina catalyst, the aliphatic aldehyde yield after 24 hours was significantly higher than the aliphatic aldehyde yield after 2 hours.

[0233] Furthermore, it was found that the reaction using ruthenium-supported alumina catalyst and phenol derivatives exhibited high aldehyde selectivity.

[0234] In Tables 1 to 3, "g" in "Catalyst" refers to the amount of metal-supported catalyst used (g), "Ru [ mmol]" refers to the amount of metal (Ru) in the metal-supported catalyst used ( mmol), and "Pd [ mmol]" refers to the amount of metal (Pd) in the metal-supported catalyst used ( mmol).

[0235] In Tables 1 to 3, "mol" in "additives" refers to the amount (mol) of the N-oxyl compound used.

[0236] In Tables 1 to 3, the "Calculation Method for Initial Aldehyde Activity (2h)" in the "Results" section was obtained according to the "Calculation Method for Initial Aldehyde Activity (2h)", the "Aldehyde Yield (2h)" was obtained according to the "Measurement Method for Aldehyde Yield (2h)", the "Alcohol Conversion Rate (24h)" was obtained according to the "Calculation Method for Alcohol Conversion Rate (24h)", the "Aldehyde Selectivity (24h)" was obtained according to the "Measurement Method for Aldehyde Selectivity (24h)", the "Carboxylic Acid Production Rate (24h)" was obtained according to the "Measurement Method for Carboxylic Acid Production Rate (24h)", and the "Aldehyde Yield (24h)" was obtained according to the "Measurement Method for Aldehyde Yield (24h)".

[0237] In Table 2, TEMPO represents 2,2,6,6-tetramethylpiperidine N-oxyl, MAZADO represents 1-methyl-2-azaadamantane-N-oxyl, AZADO represents 2-azaadamantane-N-oxyl, and NMO represents N-methylmorpholine N-oxide.

[0238] In Table 3, BHT represents dibutylhydroxytoluene, CBP represents 2,2'-methylenebis[6-(1-methylcyclohexyl)-p-cresol], AO-60 represents pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], AO-80 represents 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro[5.5]undecane, BHA represents 3-tert-butyl-4-hydroxyanisole, and DBH represents 2,5-di-tert-butylhydroquinone.

Claims

1. A method for producing an aliphatic aldehyde, comprising the step of oxidizing an aliphatic primary alcohol having 4 or more carbon atoms with molecular oxygen in the presence of a ruthenium-supported catalyst, wherein the ruthenium-supported catalyst contains ruthenium supported on a carrier, the carrier is a porous oxide, and the surface area per unit mass of ruthenium is 60 m². 2 A method for producing an aliphatic aldehyde, wherein the amount is 0.15 mL / g or more, and the mesopore volume of the ruthenium-supported catalyst is 0.15 mL / g or more.

2. The manufacturing method according to claim 1, wherein the aliphatic primary alcohol having 4 or more carbon atoms is an aliphatic linear saturated primary alcohol.

3. The manufacturing method according to claim 1 or 2, wherein the porous oxide is one or more selected from the group consisting of alumina, titania, zirconia, silica, silica-alumina, magnesia, zeolite, and activated carbon.

4. The surface area per unit mass of the ruthenium is 65 m². 2 / g or more 250m 2 A manufacturing method according to any one of claims 1 to 3, wherein the amount is less than or equal to / g.

5. The manufacturing method according to any one of claims 1 to 4, wherein the mesopore volume is 0.2 mL / g or more and 0.5 mL / g or less.

6. The manufacturing method according to any one of claims 1 to 5, wherein the ratio of ruthenium (mol) to aliphatic primary alcohol (mol) is 0.001 or more and 0.2 or less.

7. The manufacturing method according to any one of claims 1 to 6, wherein the temperature of the oxidation step is 60°C or higher and 200°C or lower.

8. The surface area per unit mass of the ruthenium is 70 m². 2 / g or more 190m 2 A manufacturing method according to any one of claims 1 to 7, wherein the amount is less than or equal to / g.

9. The method for producing an alcohol according to any one of claims 1 to 8, wherein the aliphatic primary alcohol having 4 or more carbon atoms is an aliphatic linear saturated primary alcohol having 8 to 14 carbon atoms.

10. The manufacturing method according to any one of claims 1 to 9, wherein the ruthenium metal content in the ruthenium-supported catalyst is 1% by mass or more and less than 10% by mass.

11. The oxidation step is further carried out in the presence of one or more N-oxyl compounds and / or N-oxide compounds selected from the group consisting of a compound represented by the following general formula (I), a compound represented by the following general formula (II), and a compound represented by the following general formula (III). The production method according to any one of claims 1 to 10. [In the formula, R 1 , R 2 , R 3 , and R 4 are each independently a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms which may be substituted with a substituent, and the substituent is one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group, a phenoxy group, and an acyloxy group. R 5 is an oxygen atom or a methylene group] [In the formula, R 11 , R 12 , R 13 , and R 14 are each independently a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms which may be substituted with a substituent, and the substituent is one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group, a phenoxy group, and an acyloxy group. R 15 is an oxygen atom or a methylene group] [In the formula, R 6 , and R 7 are each independently a hydrogen atom, an unsubstituted hydrocarbon group having 1 to 5 carbon atoms, or a hydrocarbon group having 1 to 5 carbon atoms which may be substituted with a substituent, and the substituent is one or more selected from the group consisting of a halogen atom, a nitro group, an alkoxy group, a phenoxy group, and an acyloxy group.] 12. The manufacturing method according to claim 11, wherein the N-oxyl compound and / or N-oxide compound is one or more selected from the group consisting of 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO), 1-methyl-2-azaadamantane-N-oxyl (MAZADO), 2-azaadamantane-N-oxyl (AZADO), and N-methylmorpholine (NMO).

13. A method for producing an aliphatic aldehyde according to any one of claims 1 to 10, wherein the oxidation step is further carried out in the presence of a phenol derivative which is a compound represented by the following general formula (IV). In the formula, R 21 R is a hydrocarbon group, hydroxyl group, or alkoxy group which may contain one or more heteroatoms selected from the group consisting of oxygen atoms and nitrogen atoms, 22 R is a hydrogen atom or a linear or branched alkyl group. 23 and R 24 R is independently a hydrogen atom, a linear or branched alkyl group, or a cycloalkyl group which may be substituted with an alkyl group, or 23 The base is represented by equation (x), and R 4 However, R is a hydrogen atom, a linear or branched alkyl group, or a cycloalkyl group which may be substituted with an alkyl group, provided that R 23 and R 24 Except when both are hydrogen atoms. [In the formula, R 51 is R 21 This is the same definition as R 52 is R 22 This is the same definition as R 54 is R 24 This is the same definition as [the previous definition]. In the formula, * indicates the bonding position.

14. In the formula, R 23 and R 24 The manufacturing method according to claim 13, wherein at least one of the members comprises a branched alkyl group having 3 to 8 carbon atoms.

15. The method for producing a compound according to claim 13 or 14, wherein the compound represented by the general formula (IV) is one or more selected from the group consisting of dibutylhydroxytoluene (BHT), 2,2'-methylenebis[6-(1-methylcyclohexyl)-p-cresol] (CBP), pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (AO-60), 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro[5.5]undecane (AO-80), and 3-tert-butyl-4-hydroxyanisole (BHA).

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