Method for producing compound, and metal polynuclear complex

Abstract

To provide a novel method useful for catalytic oxidation reactions converting a C-H bond into at least one bond selected from the group consisting of a C-OOH bond, a C-OH bond, and a C=O bond.SOLUTION: A method for producing a compound having at least one bond selected from the group consisting of a C-OOH bond, a C-OH bond, and a C=O bond, the method comprising oxidizing a compound having a C-H bond into a compound having at least one bond selected from the group consisting of a C-OOH bond, a C-OH bond, and a C=O bond, using as a catalyst a metal polynuclear complex in which a ligand of a cyclic structure or a cage structure, formed by linking one or more nitrogen-containing aromatic rings (A) with one or more nitrogen-containing non-aromatic groups (B), is bound to two or more metals.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for producing a compound by oxidation reaction, and to a polynuclear metal complex useful in this method. [Background technology]

[0002] Oxidation reactions have a wide range of applications in organic synthesis, and various methods have been studied. 3 Sp in carbon or aromatic compounds 2 The C-H bond, which consists of carbon and hydrogen atoms, is considered to be an inactive C-H bond that is difficult to oxidize, and research into its direct oxidation reaction has attracted attention. Furthermore, oxidation using a catalyst is particularly useful because it is difficult for the oxidizing agent to be mixed in as an impurity.

[0003] Non-Patent Documents 1 and 2 disclose the catalytic oxidation of benzene to phenol and the catalytic oxidation of cyclohexane to cyclohexanol using the complex shown below: [Cu(μ-OH)(6-hpa)](ClO) (where 6-hpa represents 1,2-bis[2-[bis(2-pyridylmethyl)aminoethyl-6-pyridyl]ethane). However, in the oxidation of benzene to phenol, the catalyst turnover number (TON) peaks at about 12,500, and in the oxidation of cyclohexane to cyclohexanol, the reaction peaks at about 7 hours, with a turnover number (TON) of about 1,030. [ka] [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Angew.Chem.Int.Ed.2017,56,7779-7782 [Non-patent document 2] Bull.Chem.Soc.Jpn.2022,95,1148-1155 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in light of the above-mentioned circumstances, and an object of the present invention is to provide a novel method useful for catalytically carrying out an oxidation reaction of converting a C-H bond into at least one bond selected from the group consisting of a C-OOH bond, a C-OH bond, and a C=O bond. A preferred object of the present invention is to provide a catalyst having excellent durability that can be used for the oxidation reaction. [Means for solving the problem]

[0006] The present invention, which has achieved the above object, is as follows. [1] A method for producing a compound having at least one bond selected from the group consisting of a C-OOH bond, a C-OH bond, and a C=O bond, by using a metal polynuclear complex as a catalyst in which a ligand having a cyclic structure or a cage structure formed by linking one or more nitrogen-containing aromatic rings A with one or more nitrogen-containing non-aromatic groups B is bonded to two or more metals, and oxidizing the compound having a C-H bond to a compound having at least one bond selected from the group consisting of a C-OOH bond, a C-OH bond, and a C=O bond. [2] The method according to [1], wherein the cyclic structure or cage structure further comprises an aromatic hydrocarbon ring C to which an alkyl group may be bonded. [3] The method according to [2], wherein the ligand is represented by formula (1). [ka] (In the formula, A represents the nitrogen-containing aromatic ring A, B represents the nitrogen-containing non-aromatic group B, C represents the aromatic hydrocarbon ring C, and D represents an aromatic hydrocarbon ring optionally having an alkyl group bonded thereto. m represents an integer of 1 to 3, n1 represents an integer of 0 to 2, n2 represents an integer of 0 to 2, and the sum of n1 and n2 is 0 to 2. Multiple As may be the same as or different from one another. Multiple Bs may be the same as or different from one another. Multiple Cs may be the same as or different from one another. Multiple Ds may be the same as or different from one another. Multiple ms may be the same as or different from one another.) [4] The method according to any one of [1] to [3], wherein the nitrogen-containing aromatic ring A is at least one divalent group selected from the following formulae (A1) to (A7): [ka] (In formulas (A1) to (A7), * represents a bond. An alkyl group may be bonded to the carbon atom forming the ring.) [5] The method according to any one of [1] to [4], wherein the nitrogen-containing non-aromatic group B is a group in which an -NH- group or an -N= group is inserted between the carbon-carbon bond of a hydrocarbon group, and a carbon atom of the hydrocarbon group may form a carbonyl group. [6] The method according to any one of [3] to [5], wherein the aromatic hydrocarbon ring C is at least one group selected from the following formulae (C1) and (C2): [ka] (In formulas (C1) and (C2), * represents a bond, and n is the same as above. An alkyl group may be bonded to the carbon atom forming the ring.) [7] The method according to any one of [1] to [6], wherein the metal is at least one selected from Mn, Fe, Co, Ni, Cu, and Ru. [8] The method according to any one of [1] to [7], wherein two or three nitrogen atoms selected from all nitrogen atoms possessed by the nitrogen-containing aromatic ring A and the nitrogen-containing non-aromatic group B are bonded to each of the metals. [9] The method according to any one of [1] to [8], wherein one or more nitrogen atoms selected from all nitrogen atoms possessed by the one or more nitrogen-containing aromatic rings A are bonded to each of the metals.

[10] The method according to any one of [1] to [9], wherein the compound having a C-H bond is a low-molecular-weight or high-molecular-weight compound having an aromatic hydrocarbon group, or a low-molecular-weight or high-molecular-weight compound having an aliphatic hydrocarbon group.

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

[10] , wherein an inorganic peroxide and / or molecular oxygen is used as the oxidizing agent.

[12] A polynuclear metal complex in which two or more metals are bound to a ligand having a cyclic structure or a cage structure in which one or more nitrogen-containing aromatic rings A and one or more nitrogen-containing non-aromatic groups B are linked, wherein at least one of the nitrogen-containing aromatic rings A is a pyridine ring. [Effects of the Invention]

[0007] According to the present invention, a polynuclear metal complex having a predetermined structure can be used as a catalyst to carry out an oxidation reaction of converting a C—H bond into at least one bond selected from the group consisting of a C—OOH bond, a C—OH bond, and a C═O bond. DETAILED DESCRIPTION OF THE INVENTION

[0008] 1. Polynuclear metal complexes 1.1 Ring or cage structure ligands The polynuclear metal complexes have ligands with a ring or cage structure formed by linking one or more nitrogen-containing aromatic rings A with one or more nitrogen-containing non-aromatic groups B. The multiple nitrogen-containing aromatic rings A may be the same or different, preferably the same, and the multiple nitrogen-containing non-aromatic groups B may be the same or different, preferably the same. The cyclic structure is generally a macrocyclic structure, for example, a 12- or larger-membered ring, preferably a 12- to 40-membered ring, more preferably a 16- to 36-membered ring, and even more preferably an 18- to 30-membered ring.

[0009] The group constituting the macrocyclic structure or cage structure preferably further comprises an aromatic hydrocarbon ring optionally bonded to an alkyl group; an alkylene group, etc. The ligand having a cyclic structure or cage structure is preferably a compound in which a nitrogen-containing aromatic ring A and the aromatic hydrocarbon ring are linked by a bridging moiety selected from a nitrogen-containing non-aromatic group B, an alkylene group, etc. When the nitrogen-containing aromatic ring A and the aromatic hydrocarbon ring have at least one part linked by a bridging moiety, the nitrogen-containing aromatic ring A and the aromatic hydrocarbon ring may have a part where they are directly bonded to each other.

[0010] Examples of the ligand having a nitrogen-containing aromatic ring A, a nitrogen-containing non-aromatic group B, and an aromatic hydrocarbon ring to which an alkyl group may be bonded include ligands represented by the following formula (1). [ka] (In the formula, A represents a nitrogen-containing aromatic ring, B represents a nitrogen-containing non-aromatic group, C represents an aromatic hydrocarbon ring, and D represents an aromatic hydrocarbon ring. m represents an integer of 1 to 3, n1 represents an integer of 0 to 2, and n2 represents an integer of 0 to 2, and the sum of n1 and n2 is 0 to 2. Multiple As may be the same as or different from one another. Multiple Bs may be the same as or different from one another. Multiple Cs may be the same as or different from one another. Multiple Ds may be the same as or different from one another. Multiple m's may be the same as or different from one another.) It is preferable that the plural B, C, D and m are the same as each other. m is preferably 1, n1 is preferably 0 or 1, more preferably 0, and n2 is preferably 0 or 1, more preferably 0. n1+n2 is preferably 0 or 1, more preferably 0. The combination of n1 and n2 is preferably (n1,n2)=(0,0), (1,0), or (0,1), more preferably (0,0) or (1,0), and even more preferably (0,0).

[0011] Examples of the nitrogen-containing aromatic ring A include nitrogen-containing aromatic five-membered rings (monocyclic rings) such as pyrrole and imidazole, nitrogen-containing aromatic six-membered rings (monocyclic rings) such as pyridine, pyrazine and triazine, and nitrogen-containing fused aromatic heterocycles such as isoindole and isoquinoline. A non-aromatic hydrocarbon ring may be fused to these monocyclic or fused aromatic rings, and examples thereof include the rings listed below.

[0012] [ka]

[0013] The nitrogen-containing aromatic ring A may have an alkyl group bonded thereto. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isobutyl group, a butyl group, a tert-butyl group, and a pentyl group. When multiple alkyl groups are bonded, they may be the same or different.

[0014] The nitrogen-containing aromatic ring A is preferably at least one of the formulae (A1) to (A7), and more preferably at least one of the formulae (A1) and (A3).

[0015] [ka] (In formulas (A1) to (A7), * represents a bond. An alkyl group may be bonded to the carbon atom forming the ring.)

[0016] Examples of the alkyl group in the formulae (A1) to (A7) are the same as those mentioned above, and the preferred alkyl groups are also the same.

[0017] Examples of the nitrogen-containing non-aromatic group B include a hydrocarbon group having an amino group bonded thereto (for example, a 2-aminopropane-1,3-diyl group), and a hydrocarbon group having an -NH- group or an -N= group inserted between the carbon-carbon bonds thereof, and a hydrocarbon group having an -NH- group or an -N= group inserted between the carbon-carbon bonds thereof is preferred.

[0018] In a preferred embodiment, the hydrocarbon constituting the hydrocarbon group of the nitrogen-containing non-aromatic group B includes cyclic hydrocarbons such as cyclopentane and cyclohexane, and chain hydrocarbons such as ethane, propane, and butane, and chain hydrocarbon groups are preferred. The carbon atoms of the hydrocarbon group may form a carbonyl group.

[0019] Examples of the group X in which an -NH- group or an -N= group is inserted between the carbon-carbon bond of a chain hydrocarbon group (wherein the carbon atom may form a carbonyl group) include the following X1 group, X2 group, and X3 group. It is preferable that all of the groups X are either the X1 group, the X2 group, or the X3 group, more preferably either the X1 group or the X2 group, and even more preferably the X1 group.

[0020] [ka]

[0021] Examples of the aromatic hydrocarbon ring C include a benzene ring, a monoalkylbenzene ring, a dialkylbenzene ring, and a trialkylbenzene ring. The alkyl group in the monoalkylbenzene ring, dialkylbenzene ring, and trialkylbenzene ring preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and even more preferably 1 to 3 carbon atoms.

[0022] The aromatic hydrocarbon ring C may be, for example, at least one selected from (C1) and (C2).

[0023] [ka] (In formulas (C1) and (C2), * represents a bond. n is the same as the sum of n1 and n2. An alkyl group may be bonded to the carbon atom forming the ring.)

[0024] The number of alkyl groups which may be bonded to carbon atoms forming the ring in formulae (C1) and (C2) is preferably 1 to 3, and the number of carbon atoms of the alkyl group is the same as the number of carbon atoms of the alkyl group in the monoalkylbenzene ring, dialkylbenzene ring, and trialkylbenzene ring exemplified as preferred embodiments of the aromatic hydrocarbon ring C, including the preferred range.

[0025] Preferable examples of the aromatic hydrocarbon ring C include the following.

[0026] [ka] (Me means a methyl group, Et means an ethyl group, Pr means a propyl group, and Bu means a butyl group, and * means a bond.)

[0027] However, the aromatic hydrocarbon ring C is not essential, and for example, an aliphatic hydrocarbon group having 2+n bonds may be used in place of the aromatic hydrocarbon ring C.

[0028] Preferred examples of the cyclic or cage structure ligand include those represented by formulas (10) to (21), more preferably (10) to (16), still more preferably (10) to (12), (14) to (16), and particularly preferably (10), (12), (14), and (16).

[0029] [ka]

[0030] [ka]

[0031] [ka] (In formulas (10) to (21), R 1 are the same or different and represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, or a butyl group.

[0032] 1.2 Method for producing cyclic or cage structure ligands The cyclic or cage-type ligand is formed by carrying out a Schiff base-forming reaction using a compound in which an amino group is bound to an aromatic ring (e.g., a nitrogen-containing aromatic ring A or an aromatic hydrocarbon ring C) directly or via a non-aromatic hydrocarbon group, and a compound in which an aldehyde group is bound to an aromatic ring (e.g., a nitrogen-containing aromatic ring A or an aromatic hydrocarbon ring C) directly or via a non-aromatic hydrocarbon group, and optionally reducing the Schiff base moiety. In the reaction, the nitrogen-containing non-aromatic group B is formed from the non-aromatic hydrocarbon group and the Schiff base moiety (or its reduced moiety).

[0033] 1.3 Other Ligands The metal in the polynuclear metal complex may have other ligands bonded to it in addition to the above-mentioned cyclic or cage structure ligands. The other ligands are not particularly limited and can be appropriately selected from known ligands.

[0034] Other ligands include neutral monodentate ligands such as aqua, alcohols (OHMe, OHEt, OHPr, etc.), ammine, amine, phosphine, carbonyl, isocyanide, and C≡NR; hydroxide (OH - ), alkoxides (OMe - , OEt - , OPr - OAr - etc.; the hydroxyl group of the aldol is O - oxides (including those that have become 2- ;M=O type, MOM type (μ), etc.), thiolate, sulfide, halide, cyanide, hydride, carboxylate (acetate, RCOO - etc.), nitro, nitrite, thiocyanate, isothiocyanate, oxalate, acetylacetonate, NO3 - , CO3 2- , ClO4 - , SO4 2-and nitrogen-containing ring-type ligands such as pyridine and DBU. Among the examples of other ligands, R represents an alkyl group or an aryl group (including a phenyl group), M represents a metal, Me represents a methyl group, Et represents an ethyl group, Pr represents a propyl group, and DBU represents diazabicycloundecene.

[0035] 1.4 Metal Examples of metals constituting the metal complex include fourth period metals and fifth period metals, and are preferably Mn, Fe, Co, Ni, Cu, and Ru, and more preferably Ni and Cu. The metal may be one type or two or more types, and is preferably one type.

[0036] The metal complex contains two or more metals, preferably 2 to 6, more preferably 2 to 4, and even more preferably 2 to 3 metals. Each metal is preferably bonded to 2 to 4 nitrogen atoms, more preferably 2 to 3 nitrogen atoms, selected from all nitrogen atoms contained in the nitrogen-containing aromatic ring A and the nitrogen-containing non-aromatic group B. Each metal atom is preferably bonded to one or more nitrogen atoms selected from all nitrogen atoms contained in the nitrogen-containing aromatic ring A, and most preferably to one or more nitrogen atoms selected from all nitrogen atoms contained in the nitrogen-containing non-aromatic group B in addition to this bond (i.e., most preferably to each metal atom, a nitrogen atom of the nitrogen-containing aromatic ring A and a nitrogen atom of the nitrogen-containing non-aromatic group B are bonded).

[0037] 1.5 Combinations of metals with other ligands Examples of combinations of metals and other ligands include Cu2(OH)2, Cu2(OMe)2, Cu2(OEt)2, Cu2(OAc)4, Cu2O2, Cu6O, Cu4Cl2, Cu2S2, Cu4S4, Cu4S, Cu3S2Cl2, Cu3O2Cl2, Cu2DBU2, Cu2Py2, and CuDMAP2 [Cu2(OMe)2(OHMe)2]. 2+ , [Cu2(OH)] 3+ , M 1 3(OH)3, [M 1 3(OH)3(OEt)]- , [M 1 3(OH)3Cl] - , M 1 2(OAc)4(OH2), M 1 2(OC(Me)2CH2COCH3)2), M 1 2(OAr)2(Py)2, M 1 2O(OAr)2Py, M 1 2(OCOAr)3, M 1 2(OCOAr)3(OH2), M 1 2(OCOAr)2, M 1 2(SAr)2(Py), M 1 2(SAr)2, M 1 3O3, M 1 3O2S, M 1 2S2, M 1 2{N(SiMe3)2}2(Py)2, M 1 3{N(SiMe3)2}3(THF)2, M 1 3(NHAr)3(THF)2, M 1 2(NMes)S,M 1 2(NAd)S, etc. Among these examples, M 1 represents Fe, Co, Ni, or Mn, OEt represents an ethoxy group, AcO represents acetate, Py represents pyridine, DMAP represents dimethylaminopyridine, Ar represents an aryl group, THF represents tetrahydrofuran, Mes represents a mesityl group, and Ad represents an adamantyl group.

[0038] 1.6 Method for producing polynuclear metal complexes The polynuclear metal complex can be obtained by reacting the above-mentioned ligand having a cyclic structure or a cage structure with a metal salt in a solvent. Furthermore, a solvent different from the above-mentioned solvent may be added to the reaction solution, or the reaction product obtained by the reaction may be recrystallized using a solvent different from the above-mentioned solvent. Examples of metal salts include inorganic salts such as metal hydroxides, halides, acetates, carbonates, phosphates and sulfonates, and carboxylates. Examples of the solvent include water; alcohol solvents such as methanol, ethanol, 1-propanol, 2-propanol, and 1-butanol; ether solvents such as diethyl ether and tetrahydrofuran; and halogenated hydrocarbon solvents such as methylene chloride, chloroform, and 1,2-dichlorobenzene, as well as other known solvents.

[0039] Examples of polynuclear metal complexes composed of the cyclic or cage-type ligand, the metal, and other ligands include the following L M-Py Cu2(OAc)4, [L M-Py Cu2(OR 3 )2(OHR 3 )2] 2+ , L M-Py Ni2(OAc)4(OH2), L M-Pr Cu2(OH)2, [L M-Py Cu2(OH)] 3+ Examples include: [ka]

[0040] [ka] (In the formula, R 2 , R 3 represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, and a butyl group, respectively. 2 may be the same or different. 3 may be the same or different)

[0041] 2. Catalytic Reaction The polynuclear metal complex can be used as a catalyst for oxidizing a compound having a C—H bond to a compound having at least one bond selected from the group consisting of a C—OOH bond, a C—OH bond, and a C═O bond. When used as a catalyst, the turnover number may be, for example, 2,000 or more, preferably 3,000 or more, more preferably 4,000 or more, even more preferably 9,000 or more, and still more preferably 13,000 or more, or 1,000,000 or less.

[0042] The oxidizing agent is not particularly limited, and examples thereof include oxygen molecules (including oxygen-containing gases such as oxygen gas and air), peroxides (inorganic peroxides such as hydrogen peroxide, and aliphatic or aromatic hydroperoxide compounds such as t-butyl hydroperoxide and cumene hydroperoxide), and at least one of oxygen molecules and inorganic peroxides (particularly hydrogen peroxide) is preferred.

[0043] In the oxidation reaction, Sp 3 Carbon C or Sp 2 The oxidation reaction of the hydrogen atom on the carbon atom (especially the carbon atom of the aromatic ring) to OH is preferred. 3 Carbon or Sp 2 The reaction of directly bonding oxygen to carbon is considered difficult, and the usefulness of the polynuclear metal complex lies in its ability to catalytically promote such oxidation.

[0044] The compound having a C-H bond is not particularly limited, and may be a low molecular weight compound or a high molecular weight compound. Hydrocarbons such as aliphatic hydrocarbons (aliphatic saturated hydrocarbons or aliphatic unsaturated hydrocarbons) and aromatic hydrocarbons are preferred, i.e., low molecular weight or high molecular weight compounds having an aliphatic hydrocarbon group or an aromatic hydrocarbon group are preferred. The aliphatic saturated hydrocarbons and aliphatic unsaturated hydrocarbons may be chain-like or may have a cyclic portion. Other examples include various high molecular weight compounds having a C-H bond (such as homopolymers or copolymers of methacrylic acid, polyolefin resins, styrene resins, aromatic polyester resins, and polyarylate resins). In the case of these high molecular weight compounds, the Sp possessed by each high molecular weight compound is 3 The C—H bonds of the carbon may be oxidized, and the C—H bonds of the aromatic ring may be oxidized.

[0045] It is preferable that the oxidation reaction ends in the first stage (a two-stage reaction in which a C-H bond is oxidized to form a C-OOH bond and then reduced to form a C-OH bond is also considered the first stage because it is a single oxidation reaction), and that the second stage oxidation (for example, oxidation of the second C-H bond or oxidation of a C-OH bond to C=O) does not proceed. The selectivity of the first stage oxidation relative to the entire oxidation reaction, including the oxidation in the second stage, is, for example, 70 to 100%, preferably 75 to 99%, and more preferably 80 to 98%.

[0046] The amount of the metal polynuclear complex is preferably 1.0 × 10 -7 ~1.0×10 -4 moles, more preferably 5.0 × 10 -7 ~8.0×10 -5 moles, more preferably 1.0 × 10 -6 ~5.0×10 -5 It is a mole.

[0047] The reaction temperature for the oxidation is, for example, 20 to 300°C, and preferably 30 to 250°C.

[0048] As the solvent for the oxidation reaction, water, nitrile solvents such as acetonitrile, and other known solvents can be used.

[0049] The oxidation reaction may be carried out in the presence of a base, and the base preferably used is a tertiary amine such as trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, diisopropylethylamine, tri-n-octylamine, tri-n-decylamine, triphenylamine, N,N-dimethylaniline, N,N,N',N'-tetramethylethylenediamine, N-methylpyrrolidine, 4-dimethylaminopyridine, etc. The amount of the base is preferably 1 to 10 moles, more preferably 3 to 8 moles, per mole of the polynuclear metal complex. [Example]

[0050] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples, and it is possible to carry out the invention by making appropriate modifications within the scope of the above and below-described aims, and all such modifications are included in the technical scope of the present invention.

[0051] 1. Ligand synthesis Synthesis Example 1.1 Macrocyclic Ligand L M-Py Synthesis of L M-Py was prepared according to Acta Cryst. (2013). E69, m520-m521. [ka]

[0052] Synthesis Example 1.2 Macrocyclic Ligand L M-Pr Synthesis of 2,4-bis(aminomethyl)-1,3,5-triethylbenzene (1.91 g, 8.69 mmol) was added to methanol (300 mL) and pre-dissolved. Separately, 2,5-pyrroledicarboxaldehyde (1.07 g, 8.69 mmol) was added to methanol (500 mL), and the resulting solution was added dropwise to the above solution at room temperature over 12 hours, followed by further mixing for 12 hours. The resulting suspension was filtered under reduced pressure to separate the solid, and the resulting solid was washed with methanol while filtering under reduced pressure. The washed solid was dried under reduced pressure at room temperature for 15 hours to remove the solvent, and 2.47 g of Ligand L was obtained. M-Pr was obtained (yield 92%).

[0053] [ka]

[0054] The structure of the obtained compound was determined by NMR, IR and elemental analysis.

[0055] 2. Synthesis of polynuclear metal complexes The synthesis of the following polynuclear metal complexes was all carried out under atmospheric conditions. Synthesis example 2.1 L M-Py Synthesis of Cu2(OAc)4 Macrocyclic Ligand L M-Py (48 mg, 85 μmol) was added to methanol (2 mL) to obtain a suspension. Separately, copper(II) acetate monohydrate (Cu(OAc)2·H2O) (34 mg, 0.17 mmol, where Ac represents an acetyl group) was added to water (2 mL), and the resulting solution was added to the above suspension and mixed at room temperature for 3 hours. The solvent was then evaporated under conditions of 40 °C and 100 hPa, and the resulting solid was recrystallized at room temperature using methanol and diethyl ether to obtain a precipitate. The resulting precipitate was separated as a solid by filtration under reduced pressure, and the resulting solid was washed with diethyl ether while filtering under reduced pressure. The washed solid was dried under reduced pressure at room temperature for 12 hours to remove the solvent, and 60 mg of L M-Py Cu2(OAc)4 was obtained (yield 77%).

[0056] [ka]

[0057] The structure of the obtained complex was determined by single crystal X-ray structural analysis.

[0058] Synthesis Example 2.2 [L M-Py Synthesis of Cu(OMe)(OHMe)(OTf) Macrocyclic Ligand L M-Py(44 mg, 0.079 mmol) was added to methanol (2 mL) to obtain a suspension. Separately, copper(II) trifluoromethanesulfonate (Cu(OTf)2) (57 mg, 0.16 mmol; Tf is a trifluoromethylsulfonyl group), water (0.1 mL), and triethylamine (0.1 mL) were added to methanol (2 mL), and the resulting suspension was added to the above suspension to obtain a dark blue solution. Subsequently, traces of insoluble matter were removed by filtration, and diethyl ether (1 mL) was slowly added to the resulting solution to obtain a precipitate. The resulting precipitate was separated as a solid by vacuum filtration, and the resulting solid was washed with diethyl ether while vacuum filtration. The washed solid was dried under reduced pressure at room temperature for 12 hours to remove the solvent, and 34 mg of [L M-Py Cu2(OMe)2(OHMe)2)](OTf)2 was obtained (yield 39%).

[0059] [ka]

[0060] The structure of the obtained complex was determined by single crystal X-ray structural analysis.

[0061] Synthesis Example 2.3 [L M-Py Synthesis of Cu(OH)](OTf) L M-Py (45 mg, 0.080 mmol) was added to ethanol (2 mL) to obtain a suspension. Separately, Cu(OTf)2 (58 mg, 0.16 mmol. Tf is a trifluoromethylsulfonyl group), water (0.1 mL), and triethylamine (0.1 mL) were added to ethanol (1 mL), and the resulting suspension was added to the above suspension to obtain a dark blue suspension. The resulting suspension was mixed at room temperature for 1 hour, and then the solid was separated by vacuum filtration. The resulting solid was recrystallized at room temperature using acetonitrile and diethyl ether to obtain a precipitate. The resulting precipitate was separated by vacuum filtration, and the resulting solid was washed with diethyl ether while being vacuum filtered. The washed solid was dried under vacuum at room temperature for 12 hours to remove the solvent, and 45 mg of [L M-PyCu2(OH)](OTf)3 was obtained (yield 49%).

[0062] [ka]

[0063] The structure of the obtained complex was determined by single crystal X-ray structural analysis.

[0064] Synthesis example 2.4 L M-Pr Synthesis of Cu2(OH)2 L M-Pr (39 mg, 0.064 mmol) was added to methanol (2 mL) to obtain a suspension. Separately, CuCl2·2H2O (22 mg, 0.13 mmol) was added to methanol (1 mL), and the obtained solution was added to the above suspension. 37% tetrabutylammonium hydroxide methanol solution (207 mg, 0.295 mmol) was added to the obtained brown suspension, and the solid was separated by vacuum filtration. The obtained solid was washed with diethyl ether while being vacuum filtered. The obtained solid was then recrystallized at room temperature using chloroform and diethyl ether to obtain a precipitate. The obtained precipitate was separated as a solid by vacuum filtration, and the obtained solid was washed with diethyl ether while being vacuum filtered. The washed solid was dried under vacuum at room temperature for 12 hours to remove the solvent, and 28 mg of L M-Pr Cu2(OH)2 was obtained (yield 57%).

[0065] [ka]

[0066] The structure of the obtained complex was determined by NMR and single crystal X-ray structural analysis.

[0067] 3. Oxidation of Benzene [ka]

[0068] Example 1 Under argon, benzene (5.35 mL, 60.0 mmol), a 72 mM triethylamine solution in acetonitrile (70 μL, 5.0 μmol), and 30% hydrogen peroxide (10.0 mL, 97.0 mmol) were added to acetonitrile (20 mL). M-Py A solution of Cu2(OAc)4 in acetonitrile (1.44 mL, 1.00 μmol) was added to a reaction vessel equipped with a PTFE stopcock, and a rotor was inserted and sealed. The sealed reaction vessel was heated to 50 °C in an oil bath and the reaction was carried out for a certain period of time while stirring. After cooling to room temperature, 1,2-dichlorobenzene (338 μL, 3.00 mmol) was added as an internal standard, and a portion of the solution was taken and diluted with deuterated chloroform. 1 The reaction products contained in the recovered material were analyzed qualitatively and quantitatively using a H-NMR device. 1 Qualitative analysis by H-NMR detected the main product, phenol, as well as by-products such as p-benzoquinone and catechol. From the results of quantitative analysis, the catalyst turnover number (TON) and the selectivity of each product were calculated. The formulas for these calculations are as follows: The above reaction and analysis were carried out multiple times with different reaction times, and the catalyst turnover number (TON) and selectivity were determined for each reaction time. The results are shown in Table 1. Catalyst turnover number = ((number of moles of phenol in the recovered product) + (number of moles of benzoquinone in the recovered product) x 2 + (number of moles of catechol in the recovered product) x 2) / (number of moles of catalyst added to the reaction vessel) Phenol selectivity (mol%) = (number of moles of phenol in the recovered product) / (sum of the number of moles of each product (phenol, benzoquinone) in the recovered product)

[0069] Examples 2 and 3 The same procedure as in Example 1 was carried out except that the catalyst and conditions were changed as shown in Table 1.

[0070] 4. Oxidation of cyclohexane [ka]

[0071] Example 4 Under argon, cyclohexane (6.48 mL, 60.0 mmol), a 72 mM triethylamine solution in acetonitrile (70 μL, 5.0 μmol), and 30% hydrogen peroxide (10.0 mL, 97.0 mmol) were added to acetonitrile (20 mL). M-Pr A solution of Cu2(OH)2 in acetonitrile (500 μL, 1.00 μmol) was added to a reaction vessel equipped with a PTFE stopcock, and a rotor was inserted and sealed. The sealed reaction vessel was heated to 50°C in an oil bath and allowed to react for a certain period of time while stirring. After cooling to room temperature, n-decane (585 μL, 3.00 mmol) was added as an internal standard, and a portion of the solution (0.50 mL) was sampled and triphenylphosphine (120 mg) was added. After mixing at room temperature for 30 minutes, the reaction products contained in the recovered material were analyzed qualitatively and quantitatively using a GC-MS system. Qualitative analysis by GC-MS detected the main product, cyclohexanol, as well as by-products such as cyclohexanone. Quantitative analysis was performed using a previously prepared calibration curve, and the TON and selectivity of each product were calculated from the results. The calculation formulas are as follows: Catalyst turnover number = ((number of moles of cyclohexanol in the recovered product) + (number of moles of cyclohexanone in the recovered product)) / (number of moles of catalyst added to the reaction vessel) Selectivity of cyclohexanol (mol%) = (number of moles of cyclohexanol in the recovered product) / (sum of number of moles of each product (cyclohexanol, cyclohexanone) in the recovered product)

[0072] Examples 5 and 6 The same procedure as in Example 4 was carried out except that the catalyst and conditions were changed as shown in Table 1.

[0073] [Table 1]

[0074] Examples 7 and 8 In Examples 2 and 3, the reaction time is further extended to further increase TON.

Claims

1. A method for producing a compound having at least one bond selected from the group consisting of a C—OOH bond, a C—OH bond, and a C═O bond, comprising oxidizing a compound having a C—H bond to a compound having at least one bond selected from the group consisting of a C—OOH bond, a C—OH bond, and a C═O bond using a metal polynuclear complex as a catalyst, in which a ligand having a cyclic structure or a cage structure formed by linking one or more nitrogen-containing aromatic rings A with one or more nitrogen-containing non-aromatic groups B is bound to two or more metals.

2. The method according to claim 1 , wherein the cyclic or cage structure further comprises an aromatic hydrocarbon ring C to which an alkyl group may be bonded.

3. The method according to claim 2 , wherein the ligand is represented by formula (1): 【Chemical 1】 (In the formula, A represents the nitrogen-containing aromatic ring A, B represents the nitrogen-containing non-aromatic group B, C represents the aromatic hydrocarbon ring C, and D represents an aromatic hydrocarbon ring optionally having an alkyl group bonded thereto. m represents an integer of 1 to 3, n1 represents an integer of 0 to 2, n2 represents an integer of 0 to 2, and the sum of n1 and n2 is 0 to 2. Multiple As may be the same as or different from one another. Multiple Bs may be the same as or different from one another. The multiple C's may be the same or different. The multiple Ds may be the same or different. Multiple m's may be the same or different.

4. The method according to claim 1, wherein the nitrogen-containing aromatic ring A is at least one divalent group selected from the following formulae (A1) to (A7): 【Chemistry 2】 (In formulas (A1) to (A7), * represents a bond. An alkyl group may be bonded to a carbon atom forming a ring.)

5. The method according to claim 1, wherein the nitrogen-containing non-aromatic group B is a hydrocarbon group having an —NH— group or an —N═ group inserted between the carbon-carbon bond thereof, and a carbon atom of the hydrocarbon group is a group which may form a carbonyl group.

6. The method according to claim 3 , wherein the aromatic hydrocarbon ring C is at least one group selected from the following formulae (C1) and (C2): 【Chemistry 3】 (In formulas (C1) and (C2), * represents a bond, and n is the same as above. An alkyl group may be bonded to the carbon atom forming the ring.)

7. 2. The method according to claim 1, wherein the metal is at least one selected from the group consisting of Mn, Fe, Co, Ni, Cu, and Ru.

8. 2. The method according to claim 1, wherein two or three nitrogen atoms selected from all nitrogen atoms contained in the nitrogen-containing aromatic ring A and the nitrogen-containing non-aromatic group B are bonded to each of the metals.

9. 2. The method according to claim 1, wherein one or more nitrogen atoms selected from all nitrogen atoms contained in the one or more nitrogen-containing aromatic rings A are bonded to each of the metals.

10. 2. The method according to claim 1, wherein the compound having a C—H bond is a low-molecular-weight or high-molecular-weight compound having an aromatic hydrocarbon group, or a low-molecular-weight or high-molecular-weight compound having an aliphatic hydrocarbon group.

11. The method according to claim 1, wherein an inorganic peroxide and / or molecular oxygen is used as the oxidizing agent.

12. A polynuclear metal complex in which two or more metals are bound to a ligand having a cyclic structure or a cage structure in which one or more nitrogen-containing aromatic rings A and one or more nitrogen-containing non-aromatic groups B are linked, wherein at least one of the nitrogen-containing aromatic rings A is a pyridine ring.

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