JP6830320B2 - Electrodes for magnesium-air batteries and magnesium-air batteries - Google Patents

Description

The present invention relates to an electrode for a magnesium-air battery and a magnesium-air battery.

Since oxygen, which is a positive electrode active material, is supplied from the outside of the magnesium-air battery, it is not necessary to store the positive electrode active material in the battery. Therefore, a large amount of negative electrode active material can be filled in the battery, and a very high energy density can be achieved, which is expected.

A magnesium air battery is a battery having a positive electrode having an oxygen reducing ability, a negative electrode using magnesium or a magnesium alloy as a negative electrode active material, and an electrolytic solution. The discharge reaction of the battery is expressed by the following equation.
Positive electrode: O ₂ + 2H ₂ O + 4e ⁻ → 4OH ⁻
Negative electrode: 2Mg + 4OH ⁻ → 2Mg (OH) ₂ + 4e ⁻
Total reaction: 2Mg + O ₂ + 2H ₂ O → 2Mg (OH) ₂

As a magnesium-air battery, for example, Patent Document 1 discloses a magnesium-air battery using carbon (carbon fiber sheet) as a positive electrode.

Japanese Unexamined Patent Publication No. 2011-181382

However, the magnesium-air battery described in Patent Document 1 in which only carbon is used as the positive electrode has a problem that a large amount of hydrogen peroxide is generated.

The present invention has been made in view of such circumstances, and provides an electrode for a magnesium-air battery and a magnesium-air battery that suppress the generation of hydrogen peroxide.

That is, the present invention provides the following inventions.
The present invention first provides an electrode for a magnesium-air battery containing one or more metal complexes selected from the group consisting of cobalt complexes and iron complexes.
Secondly, the present invention provides the electrode for a magnesium-air battery in which the metal complex is a cobalt complex.
Thirdly, the present invention provides the electrode for a magnesium air battery in which the cobalt complex has a coordination atom and at least one of the coordination atoms is a nitrogen atom or an oxygen atom.
Fourth, the present invention provides the magnesium air battery electrode in which the cobalt complex has two or more coordination atoms, and the coordination atoms are nitrogen atoms and oxygen atoms.
Fifth, the present invention provides the magnesium-air battery electrode in which the cobalt complex is a polynuclear complex.
Sixth, the present invention provides the magnesium-air battery electrode in which the metal complex is an iron complex.
Seventh, the present invention provides the magnesium air battery electrode in which the iron complex has a coordination atom and all of the coordination atoms are nitrogen atoms.
Eighth, the present invention further provides the magnesium-air battery electrode containing conductive carbon.
Ninth, the present invention provides a magnesium-air battery having the electrode for the magnesium-air battery.

According to the present invention, when a magnesium-air battery is generated, the amount of hydrogen peroxide generated can be suppressed.

It is a schematic schematic diagram which shows an example of the magnesium-air battery of this embodiment.

Hereinafter, the present embodiment will be described in detail.

<Electrode>
The electrode for a magnesium-air battery of the present invention contains one or more metal complexes selected from the group consisting of cobalt complexes and iron complexes.

(Cobalt complex)
The cobalt complex has a cobalt atom or an ion as a central metal and is composed of an organic ligand. The organic ligand has a coordination atom that coordinates with the central metal, and it is preferable that at least one of the coordination atoms is a nitrogen atom or an oxygen atom, and all of the coordination atoms are nitrogen. More preferably, it is an atom and / or an oxygen atom, and even more preferably all of the coordinating atoms are a nitrogen atom and an oxygen atom. The cobalt complex preferably has an oxygen reducing ability. Here, the reducing ability of oxygen means that oxygen can be reduced to hydroxide ions.

Cobalt complexes having the ability to reduce oxygen include cobalt mononuclear complexes such as cobalt porphyrin, cobalt benzoporphyrin, cobalt phthalocyanine, cobalt porphycene, and sarcomine, and cobalt polynuclear complexes having multiple cobalt atoms or cobalt ions in one molecule. Etc. are exemplified.

A specific structural formula will be illustrated for the cobalt mononuclear complex. The hydrogen atom in the structural formula may be substituted with another substituent. Charges and counterions are omitted.

A specific structural formula of the cobalt polynuclear complex will be illustrated. The hydrogen atom in the structural formula may be substituted with another substituent. The charge and counterion of the cobalt polynuclear complex are omitted. A part of cobalt may be replaced with another metal atom or metal ion.

Examples of the substituent include a halogeno group such as a fluoro group, a chloro group, a bromo group and an iodo group; a hydroxy group; a carboxyl group; a mercapto group; a sulfonic acid group; a nitro group; a phosphonic acid group; an alkyl group having 1 to 4 carbon atoms. Cyril group having: methyl group, ethyl group, propyl group, isopropyl group, cyclopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, cyclopentyl group, hexyl group, cyclohexyl group, norbornyl group, Nonyl group, cyclononyl group, decyl group, 3,7-dimethyloctyl group, adamantyl group, dodecyl group, cyclododecyl group, pentadecyl group, octadecyl group, docosyl group and other linear, branched or cyclic groups having 1 to 50 total carbon atoms. Saturated hydrocarbyl group; methoxy group, ethoxy group, propyloxy group, butoxy group, pentyloxy group, cyclohexyloxy group, norbornyloxy group, decyloxy group, dodecyloxy group, etc. , Branched or cyclic alkoxy groups; monovalent aromatic groups having 6 to 60 total carbon atoms such as phenyl group, 4-methylphenyl group, 1-naphthyl group, 2-naphthyl group, 9-anthryl group and the like are exemplified. Preferably, a halogeno group, a mercapto group, a hydroxy group, a carboxyl group, a saturated hydrocarbyl group having 1 to 20 carbon atoms, a linear or branched alkoxy group having 1 to 10 total carbon atoms, and a monovalent group having 6 to 30 total carbon atoms. It is an aromatic group, more preferably a chloro group, a bromo group, a hydroxy group, a carboxyl group, a methyl group, an ethyl group, a tert-butyl group, a cyclohexyl group, a norbornyl group, an adamantyl group, a methoxy group, an ethoxy group, and the like. It is a phenyl group.

(Iron complex)
The iron complex has an iron atom or an ion as a central metal and is composed of an organic ligand. The organic ligand has a coordination atom that coordinates with the central metal, and it is preferable that at least one of the coordination atoms is a nitrogen atom or an oxygen atom, and all of the coordination atoms are nitrogen. It is more preferably an atom. The iron complex preferably has the ability to reduce oxygen.

Examples of the iron complex having an oxygen reducing ability include iron mononuclear complexes such as iron phthalocyanine and iron naphthalocyanine, and iron polynuclear complexes having a plurality of iron atoms or iron ions in one molecule.

A specific structural formula of the iron mononuclear complex will be illustrated. The hydrogen atom in the structural formula may be substituted with another substituent. Charges and counterions are omitted.

A specific structural formula of the iron polynuclear complex will be illustrated. The hydrogen atom in the structural formula may be substituted with another substituent. The charge and counterion of the iron polynuclear complex are omitted. A part of iron may be replaced with another metal atom or metal ion.

Examples of the substituent include the same ones as described above.

The metal complex used for the electrode for a magnesium air battery of the present invention is a density functional theory (B3LYP / LANL2DZ), and the amount of energy change due to the metal complex adsorbing oxygen molecules is -50 to -230 kJ / mol. It is preferable to calculate. Within this range, an electrode for a magnesium-air battery having excellent oxygen reduction can be obtained.

(Explanation of density functional theory (B3LYP / LANL2DZ))
The metal complex used for the electrode for a magnesium air battery of the present invention is a density functional theory (B3LYP / LANL2DZ), and the amount of energy change due to the metal complex adsorbing oxygen molecules is -50 to -230 kJ / mol. It is preferable to calculate. The amount of change in energy is more preferably −55 to −200 kJ / mol, and particularly preferably −60 to −180 kJ / mol. The program for performing the above energy calculation is GAUSSIAN 09 of GAUSSIAN INC. When calculating the energy, the structure optimization calculation is performed in the most stable spin state in each of the possible states of the cation state, the neutral state, and the anion state, and the energy value in the most stable state is adopted. Further, when performing the above energy calculation, the structure is such that the substituents that are considered to be hydrated and desorbed are excluded from the metal complex. For the structure on which oxygen molecules are adsorbed, the structure optimization calculation is performed in the most stable state and in the most stable spin state, and the energy value in the most stable state is adopted. The energy value of the complex before adsorption and the energy value of the oxygen molecule alone are subtracted from the energy value to obtain the energy change amount. As a method for selecting a metal complex, for example, by calculating the amount of energy change of a known metal complex, those included in the above range can be appropriately selected.
The reason why an electrode for a magnesium-air battery having excellent oxygen reduction can be obtained by using such a metal complex as an electrode for a magnesium-air battery is not clear, but the present inventors presume as follows.
In the catalytic reaction using a metal complex, it is generally considered that a coordination unsaturated place is generated so that a reactive molecule can be easily coordinated. Among these metal complexes, a halogen, an alkoxy group, or a carboxyl is generated. In a complex having a relatively small size and highly water-soluble ligand such as an acid group, it is considered that the ligand is desorbed in water and the oxygen molecule is easily coordinated with the central metal. It is considered that the reduction reaction also proceeds in the metal complex existing in the positive electrode of the magnesium-air battery of the present invention in a structure having a similar coordination unsaturated place. Further, this oxygen molecule reduction reaction occurs at the positive electrode. In this positive electrode, electrons come from the negative electrode through the conductor, so that the metal complex is likely to become an anion. It is considered necessary for oxygen molecules to be stably adsorbed on the metal complex that is coordinate unsaturated and has become an anion. However, excessive stabilization may cause undesired reactions such as simple oxidation of the metal, so it is considered that moderate stability is sufficient. Therefore, in the present invention, the oxygen molecule adsorption capacity of the metal complex was calculated by quantum chemistry calculation.

Further, in the metal complex of the present invention, the amount of energy change associated with the adsorption of water molecules by the anionic metal complex is calculated to be 0 to -80 kJ / mol by the density functional theory (B3LYP / LANL2DZ). Is preferable. The amount of change in energy associated with the adsorption of water molecules is more preferably -20 to -75 kJ / mol, and particularly preferably -40 to -70 kJ / mol. The same program as described above is used for the above energy calculation program, and the calculation is performed by replacing the oxygen molecule with the water molecule in the same manner as described above.

A preferable structural formula is exemplified for a metal complex in which the amount of energy change due to adsorption of oxygen molecules is calculated to be −50 to −230 kJ / mol. The hydrogen atom in the structural formula may be substituted with another substituent. Charges and counterions are omitted. Further, M represents iron or cobalt.

Examples of the substituent include a halogeno group such as a fluoro group, a chloro group, a bromo group and an iodo group; a hydroxy group; a carboxyl group; a mercapto group; a sulfonic acid group; a nitro group; a phosphonic acid group; an alkyl group having 1 to 4 carbon atoms. Cyril group having: methyl group, ethyl group, propyl group, isopropyl group, cyclopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, cyclopentyl group, hexyl group, cyclohexyl group, norbornyl group, Nonyl group, cyclononyl group, decyl group, 3,7-dimethyloctyl group, adamantyl group, dodecyl group, cyclododecyl group, pentadecyl group, octadecyl group, docosyl group, etc. Saturated hydrocarbyl group; methoxy group, ethoxy group, propyloxy group, butoxy group, pentyloxy group, cyclohexyloxy group, norbornyloxy group, decyloxy group, dodecyloxy group, etc. , Branched or cyclic alkoxy groups; monovalent aromatic groups having 6 to 60 total carbon atoms such as phenyl group, 4-methylphenyl group, 1-naphthyl group, 2-naphthyl group, 9-anthryl group and the like are exemplified. Preferably, a halogeno group, a mercapto group, a hydroxy group, a carboxyl group, a saturated hydrocarbyl group having 1 to 20 carbon atoms, a linear or branched alkoxy group having 1 to 10 total carbon atoms, and a monovalent group having 6 to 30 total carbon atoms. It is an aromatic group, more preferably a chloro group, a bromo group, a hydroxy group, a carboxyl group, a methyl group, an ethyl group, a tert-butyl group, a cyclohexyl group, a norbornyl group, an adamantyl group, a methoxy group, an ethoxy group, and the like. It is a phenyl group.

（式（１）中、Ｑ^１、Ｒ^１、Ｒ^２、Ｒ^３はそれぞれ独立に水素原子または一価の置換基である。複数のＱ^１、Ｒ^１、Ｒ^２、Ｒ^３はそれぞれ同じでも異なっていてもよい。式（１）中、電荷の記載は省略してある。） The metal complex of the present invention preferably uses an aromatic compound represented by the formula (1) as a ligand. By using this complex, an electrode for a magnesium-air battery having excellent oxygen reduction can be obtained.

(In formula (1), Q ¹ , R ¹ , R ² , and R ³ are independent hydrogen atoms or monovalent substituents. Even if a plurality of Q ¹ , R ¹ , R ² , and R ³ are the same, respectively. It may be different. In the equation (1), the description of the electric charge is omitted.)

In the formula (1), the description of the electric charge is omitted. N in the formula (1) may have a proton attached, and the phenolate in the formula (1) may have a proton attached to have a phenolic structure.

The above R ¹ , R ² and R ³ are independently hydrogen atoms or monovalent substituents. Examples of monovalent substituents in R ¹ , R ² , and R ³ include halogen atoms, hydroxyl groups, carboxyl groups, mercapto groups, sulfonic acid groups, nitro groups, phosphonic acid groups, and alkyl groups with a total carbon number of 1. ~ 18 silyl groups, linear, branched or cyclic saturated hydrocarbon groups with 1 to 50 total carbons, linear, branched or cyclic alkoxy groups with 1 to 50 total carbons, aromatics with 6 to 60 total carbons. Group groups are exemplified.
Examples of the halogen atom include a fluorine atom and a chlorine atom.
Examples of the silyl group having an alkyl group having a total carbon number of 1 to 18 include a trimethylsilyl group and a tert-butyldimethylsilyl group.
Examples of the linear, branched or cyclic saturated hydrocarbon group having 1 to 50 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a cyclopropyl group, a butyl group, an isobutyl group, a tert-butyl group and a pentyl. Group, cyclopentyl group, hexyl group, cyclohexyl group, norbonyl group, nonyl group, cyclononyl group, decyl group, 3,7-dimethyloctyl group, adamantyl group, dodecyl group, cyclododecyl group, pentadecyl group, octadecyl group, docosyl group, etc. Is exemplified.
Examples of the linear, branched or cyclic alkoxy group having 1 to 50 total carbon atoms include a methoxy group, an ethoxy group, a propioxy group, a butoxy group, a pentyloxy group, a butoxy group, a pentyloxy group, a cyclohexyloxy group and a norbonyloxy group. Examples include a group, a decyloxy group, and a dodecyloxy group.
Examples of the aromatic group having 6 to 60 total carbon atoms include a phenyl group, a 4-methylphenyl group, a 4-octylphenyl group, a 1-naphthyl group, a 2-naphthyl group, and a 9-anthryl group.

The R ¹ is preferably a hydrogen atom, a linear, branched or cyclic saturated hydrocarbon group having 1 to 50 total carbon atoms, or an aromatic group having 6 to 60 total carbon atoms, and is a direct hydrogen atom having 1 to 18 total carbon atoms. Chain, branched or cyclic saturated hydrocarbon groups, aromatic groups having 6 to 36 total carbon atoms are more preferable, aromatic groups having 6 to 18 total carbon atoms are further preferable, and phenyl groups are particularly preferable. The phenyl group may have an alkyl group having 1 to 16 carbon atoms as a substituent.

The R ² is preferably a hydrogen atom, a linear, branched or cyclic saturated hydrocarbon group having 1 to 50 total carbon atoms, more preferably a hydrogen atom or a linear saturated hydrocarbon group having 1 to 18 total carbon atoms, and a hydrogen atom. Is more preferable.
There are four R ² may be the same or different from each other, but are preferably the same.

Wherein R ³ is a hydrogen atom, a halogen atom, a hydroxyl group, a linear total carbon number of 1 to 50, branched or cyclic saturated hydrocarbon group, a straight-chain, branched alkoxy group or a cyclic total carbon number of 1 to 50 preferably , Hydrogen atom, linear or branched saturated hydrocarbon group with total carbon number 1-18, linear or branched alkoxy group with total carbon number 1-18 is more preferable, and hydrogen atom, total carbon number 1-18 direct Chain or branched saturated hydrocarbon groups are more preferred.
6 There R ³ may be the same or different, respectively, but are preferably different. Of 6 There R ^3, when viewed from the position of the substituent O benzene ring linked with R ^3, R ³ in the meta position, from the total straight-chain or branched saturated hydrocarbon group having a carbon number of 1 to 18 Is also preferably a hydrogen atom. When viewed from the position of the O of the benzene ring with R ^3, R ³ in the para position is preferred over the hydrogen atom a straight-chain or branched saturated hydrocarbon group having 1 to 18 carbon total carbon.

The above Q ¹ is a hydrogen atom or a monovalent substituent. Examples of the monovalent substituent in Q ¹ include the same monovalent substituents in R ¹ , R ² , and R ³ , and in addition, a furan ring, a thiophene ring, a pyrrole ring, a pyridine ring, and a pyrazine ring. Examples thereof include aromatic heterocycles having a total carbon number of 3 to 60, such as a pyrimidine ring, a pyridazine ring, an imidazole ring, and a phosphabenzene ring. These rings may have a halogen atom, a hydrocarbyl group having 1 to 18 carbon atoms, or a hydrocarbyloxy group having 1 to 18 carbon atoms as a substituent. However, since the substituent can be introduced for the purpose of increasing the solubility in a general-purpose solvent and improving the operability within a range that does not affect the oxygen reduction activity, carbon having a small electronic contribution to the metal center Hydrocarbyl groups having 1 to 18 atoms are preferable. Further, these rings may be further condensed with aromatic rings.
In addition, these rings are monovalent substituents in Q ¹ is, because it is a monovalent substituent, refers to a group obtained by removing one hydrogen atom from these rings. For example, if the these rings specifically pyridine ring, Q ¹ is pyridyl group.

Preferably there are two Q ¹ is at least one rather than a two even hydrogen atom a monovalent substituent, more preferably both of the two is a monovalent substituent.

Examples of the monovalent substituent in Q ^1, a halogen atom, a hydroxyl group, a carboxyl group, a mercapto group, a sulfonic acid group, a nitro group, a phosphonic acid group, the total straight-chain or branched saturated hydrocarbon group having a carbon number of 1 to 18 , An aromatic group having a total carbon number of 6 to 18 and an aromatic heterocycle having a total carbon number of 3 to 18 are preferable, and a halogen atom and an aromatic heterocycle having a total carbon number of 3 to 18 are more preferable. The aromatic heterocycle is preferably a nitrogen-containing heterocycle because it has a high oxygen reduction activity. Examples of the nitrogen-containing heterocycle include a pyridine ring, a pyrimidine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, a phenanthroline ring, a bipyridine ring, a dipyrrolyl methylene ring, a quinoline ring, an isoquinoline ring, an imidazole ring, a pyrazole ring, and an oxazole. Examples thereof include a ring, a thiazole ring, an oxadiazole ring, a thiaziazole ring, an azadiazole ring, an aclysin ring, and an N-alkylpyrrole ring, and a pyridine ring, a pyridazine ring, a pyrimidine ring, a phenanthroline ring, a bipyridine ring, and an imidazole ring are preferable. , Pyridine ring, pyridazine ring, pyrimidine ring are more preferable. Halogen atom as the substituent in Q ¹ represents a chlorine atom or a bromine atom.

When Q ¹ is bulky above a certain level, the molecular structure of the ligand impairs the flatness due to the steric repulsion between the two Q ^1, and the oxygen reduction activity decreases. Therefore, Q ¹ is represented by the formula (1). It is preferable that the aromatic compound is a substituent having a small bulk so as to maintain flatness.
There are two Q ¹ may be the same or different, but as there are two Q ¹ together as described above is not a steric repulsion, if to Q ¹ one bulky the other Q ¹ is compact It is preferable to have. For example, if one Q ¹ is a phenanthroline ring or a bipyridine ring, the other Q ¹ is preferably a hydrogen atom or a halogen atom.
From the standpoint of manufacturability, it is preferred that there are two Q ¹ are the same.

Specific examples of the aromatic compound represented by the formula (1) are shown below (A1) to (A30).

The charges of (A1) to (A30) are omitted as in the equation (1). Me is a methyl group, Et is an ethyl group, nBu is a normal butyl group, tBu is a tert-butyl group, nOct is a normal octyl group, and tOct is a tert-octyl group. When R is described in (A1) to (A30), R is a hydrogen atom or a hydrocarbyl group having 1 to 18 carbon atoms. When R is a hydrogen atom, it may come off as a proton.
Of A1～A30, in view steric hindrance is small substituents each other corresponding to two for ^{Q 1} in the formula (1), preferably A1~A3, A5~A13, A15, A16, A18, A20, A22, a A24～30, from the viewpoint that at least one halogen atom or a nitrogen-containing heterocycle of the substituents corresponding to two for ^{Q 1} in the formula (1), more preferably a5 through a13, A15, A20, A22 a A24～29, more preferably from the viewpoint substituents corresponding to two for ^{Q 1} in the formula (1) is the same, a5 through a13, a A15, A20, A22.

The metal complex may have a counter anion so that the whole is neutral depending on the number of metals and the electric charge. An example of the type of counter anion is the anion portion of a metal salt described later. That is, for example, it may have an acetate ion, a halide ion, or the like. The metal complex preferably has 0 to 1 counter anions per molecule of the complex from the viewpoint of ease of handling when used as an electrode.

Specific examples of the metal complex having the aromatic compound represented by the formula (1) as a ligand are described below in Co-A5, Co-A6, Co-A7, Co-A8, Fe-A5, Fe-A6, Fe-A7, Fe-A8, Co2-A9, Co2-A10, Fe2-A11, FeCo-A12, Co-A9, Co-A10, Fe-A11, Co-A12, Co-A20, Fe-A20, Co2- It is shown in A22, Fe2-A22, Co2-A24, Co2-A25, Co2-A26, Co2-A27, Co2-A28, and Co2-A29.

The charge and counter anion in the above equation are omitted. When R is described, R is a hydrogen atom or a hydrocarbyl group having 1 to 18 carbon atoms.
Co-A5, Co-A6, Co-A7, Co-A8, Fe-A5, Fe-A6, Fe-A7, Fe-A8, Co2-A9, Co2-A10, Fe2-A11, FeCo-A12, Co- A9, Co-A10, Fe-A11, Co-A12, Co-A20, Fe-A20, Co2-A22, Fe2-A22, Co2-A24, Co2-A25, Co2-A26, Co2-A27, Co2-A28, of co2-A29, from the viewpoint substituents ligand structure corresponds to two for ^{Q 1} in the formula (1) is the same, preferably, Co-A5, Co-A6 , Co-A7, Co- A8, Fe-A5, Fe-A6, Fe-A7, Fe-A8, Co2-A9, Co2-A10, Fe2-A11, FeCo-A12, Co-A9, Co-A10, Fe-A11, Co-A12, Co-A20, Fe-A20, Co2-A22, Fe2-A22. From the viewpoint that the metal type is iron or cobalt, more preferably Co-A5, Co-A6, Co-A7, Co-A8, Fe-A5, Fe-A6, Fe-A7, Fe-A8, Co2-A9, Co2-A10, Fe2-A11, FeCo-A12, Co-A9, Co-A10, Fe-A11, Co-A12, Co-A20, Fe-A20, Co2-A22, Fe2-A22. From the viewpoint of containing cobalt in the metal species, more preferably Co-A5, Co-A6, Co-A7, Co-A8, Co2-A9, Co2-A10, FeCo-A12, Co-A9, Co-A10, Co- A12, Co-A20, Co2-A22.

(Manufacturing method of metal complex)
Next, a method for producing the metal complex used in the present invention will be described.
The method for producing the metal complex is not particularly limited, but the metal complex having an oxygen reducing ability preferably used in the present invention is, for example, a compound obtained after organically synthesizing a ligand compound. Is mixed with a reactant that imparts a metal atom or a metal ion (hereinafter, referred to as “metal-imparting agent”) and reacted. The amount of the metal-imparting agent to be reacted is not particularly limited, and the amount of the metal-imparting agent may be adjusted according to the target metal complex, but usually, an excessive amount of the metal-imparting agent is added to the ligand compound. It is preferable to react.

A specific structural formula will be exemplified for the ligand compound. The hydrogen atom in the structural formula may be substituted with another substituent.

When the central metal is cobalt, the metal-imparting agent includes cobalt acetate (II), cobalt acetate (III), cobalt chloride (II), cobalt fluoride (II), cobalt fluoride (III), and cobalt bromide. (II), cobalt iodide (II), cobalt sulfate (II), cobalt carbonate (II), cobalt nitrate (II), cobalt hydroxide (II), cobalt phosphate (II), cobalt perchlorate (II) , Cobalt trifluoroacetate (II), cobalt trifluoromethanesulfonate (II), cobalt tetrafluoroborate (II), cobalt hexafluorophosphate (II), cobalt tetraphenylborate (II), cobalt stearate (II) ), Cobalt benzoate (II) and the like, preferably cobalt acetate (II) and cobalt chloride (II).

The metal imparting agent may be a hydrate, and examples thereof include cobalt (II) acetate tetrahydrate and cobalt (II) chloride hexahydrate.

When the central metal is iron, the metal-imparting agent includes iron (II) acetate, iron (II) chloride, iron (III) chloride, iron (II) bromide, iron (III) bromide, and iron fluoride. (II), iron fluoride (III), iron sulfate (II), iron sulfate (III), iron nitrate (III), iron phosphate (III), iron perchlorate (II), iron perchlorate (III) ), Iron trifluoroacetate (II), iron trifluoromethanesulfonate (II), iron tetrafluoroborate (II), iron tetraphenylborate (II), iron stearate (II), iron stearate (III) , Etc., and iron (II) acetate, iron (II) chloride, and iron (III) chloride are preferable.

The metal imparting agent may be a hydrate, and examples thereof include iron (II) chloride tetrahydrate and iron (III) chloride hexahydrate.

The step of mixing the ligand compound and the metal-imparting agent is carried out in the presence of a suitable solvent. As the solvent (reaction solvent) used in the reaction, water; organic acids such as acetic acid and propionic acid; amines such as aqueous ammonia and triethylamine; methanol, ethanol, n-propanol, isopropyl alcohol, 2-methoxyethanol, etc. Alcohols such as 1-butanol, 1,1-dimethylethanol; ethylene glycol, diethyl ether, 1,2-dimethoxyethane, methyl ethyl ether, 1,4-dioxane, tetrahydrofuran, benzene, toluene, xylene, mesityrene, durene, Aromatic hydrocarbons such as decalin; halogen-based solvents such as dichloromethane, chloroform, carbon tetrachloride, chlorobenzene, 1,2-dichlorobenzene, N, N'-dimethylformamide, N, N'-dimethylacetamide, N-methyl- Examples thereof include 2-pyrrolidone, dimethylsulfoxide, acetone, acetonitrile, benzonitrile, triethylamine and pyridine. These reaction solvents may be used alone or in combination of two or more. Further, as the solvent, a solvent in which an aromatic compound serving as a ligand and a metal imparting agent can be dissolved is preferable.

The mixing temperature of the ligand compound and the metal-imparting agent is preferably −10 ° C. or higher and 250 ° C. or lower, more preferably 0 ° C. or higher and 200 ° C. or lower, and further preferably 0 ° C. or higher and 150 ° C. or lower.

The mixing time of the ligand compound and the metal-imparting agent is preferably 1 minute or more and 1 week or less, more preferably 5 minutes or more and 24 hours or less, and further preferably 1 hour or more and 12 hours or less. The mixing temperature and mixing time are preferably adjusted in consideration of the types of the ligand compound and the metal-imparting agent.

The produced metal complex can be taken out from the solvent by selecting and applying a suitable method from known recrystallization methods, reprecipitation methods, chromatography methods and the like. At this time, a plurality of the above methods can be used. It may be combined. Depending on the type of the solvent, the formed metal complex may be precipitated. In this case, the precipitated metal complex may be separated by filtration or the like and then washed, dried or the like.

One type of each of the metal complexes may be used alone, or two or more types may be mixed and used.

The metal complex may be mixed by any known method, and may be mixed, for example, in an agate mortar.

Next, a method for producing the aromatic compound represented by the formula (1) will be described.
The aromatic compound represented by the formula (1) can be synthesized by combining generally known reactions, and is not particularly limited. For example, it can be suitably produced by the scheme of the formula (4) shown below.

式（４）に一形態を示す。原料としてＱ^１とピロール環を有する化合物を有機化学的に合成した後、Ｒ^１を有するアルデヒド化合物を混合して、ピロール環部位へ結合させることができる。得られる中間生成物は２つのピロール環の間にメチン構造を有するので、メチン水素を適切な酸化剤を用いてメチレン体に変換することで本発明の芳香族化合物を得ることができる。前記酸化剤は、空気中の酸素や２，３−ジクロロ−５，６−ジシアノ−ｐ−ベンゾキノン（ＤＤＱ）などの一般的な酸化剤を適宜選択して用いることができる。式（４）の反応は、一般的にポルフィリン誘導体を合成する際の環化反応などに用いられる汎用な手法を適応することができる。

One form is shown in the formula (4). After a compound having Q ^1, a pyrrole ring and organic chemical synthesis as starting materials, by mixing the aldehyde compound having R ^1, it can be attached to the pyrrole ring moiety. Since the resulting intermediate product has a methine structure between the two pyrrole rings, the aromatic compound of the present invention can be obtained by converting methine hydrogen into a methylene form using an appropriate oxidizing agent. As the oxidizing agent, oxygen in the air or a general oxidizing agent such as 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) can be appropriately selected and used. For the reaction of the formula (4), a general-purpose method generally used for a cyclization reaction when synthesizing a porphyrin derivative can be applied.

In formula (4), a general-purpose protecting group may be attached to each of the OH site and the NH site. For example, the H site of OH may be in a state of being protected by methoxymethyl or methyl, and the H site of NH may be in a state of being protected by tert-butoxycarbonyl. In this case, the aromatic compound represented by the formula (1) can be synthesized by carrying out the deprotection reaction after the reaction of the formula (4).

Further, Q ¹ in the formula (4) may be a substituent different from Q ² that can be converted to Q ² in the subsequent reaction. For example, Q ² sites in equation (4) is a bromine atom or an iodine atom, Suzuki reaction after the reaction of formula (4), Yamamoto reaction, Hiyama reaction, nitrogen-containing heterocyclic by performing the cross-coupling reactions such as Stille reactions It can be converted to a ring group.

Next, a method for producing a metal complex using the aromatic compound represented by the formula (1) as a ligand will be described.
The method for producing the metal complex is not particularly limited, but after organically synthesizing the aromatic compound represented by the formula (1), a metal salt containing the desired metal species is added to the obtained compound. It is obtained by mixing and reacting in a solvent. The amount of the metal salt to be reacted is not particularly limited, and the amount of the metal salt may be adjusted according to the target complex, but usually, a small excess amount of the metal salt with respect to the aromatic compound serving as a ligand is used. Is preferably used.

Examples of the metal salt include iron (II) acetylacetonate, iron (III) acetylacetonate, iron (II) sulfate, iron (II) acetate, iron (II) trifluoromethanesulfonate, iron (II) chloride, and chloride. Iron (III), Iron Nitrate (III), Iron (II) methoxydo, Iron (II) ethoxydo, Cobalt (II) acetate, Cobalt (III) acetate, Cobalt chloride (II), Cobalt fluoride (II), Fluoride Cobalt (III), cobalt bromide (II), cobalt iodide (II), cobalt sulfate (II), cobalt carbonate (II), cobalt nitrate (II), cobalt hydroxide (II), cobalt phosphate (II) , Cobalt perchlorate (II), cobalt trifluoroacetate (II), cobalt trifluoromethanesulfonate (II), cobalt tetrafluoroborate (II), cobalt hexafluorophosphate (II), cobalt tetraphenylborate (II) Examples thereof include cobalt stearate (II), cobalt benzoate (II), and iron acetate (II), iron chloride (II), cobalt acetate (II), and cobalt chloride (II).

The metal salt may be a hydrate, and examples thereof include iron (II) chloride tetrahydrate, cobalt (II) acetate tetrahydrate, and cobalt (II) chloride hexahydrate.

The step of mixing the aromatic compound and the metal salt is carried out in the presence of a suitable solvent. As the solvent (reaction solvent) used in the reaction, water; organic acids such as acetic acid and propionic acid; amines such as aqueous ammonia and triethylamine; methanol, ethanol, n-propanol, isopropyl alcohol, 2-methoxyethanol, etc. Alcohols such as 1-butanol, 1,1-dimethylethanol; ethylene glycol, diethyl ether, 1,2-dimethoxyethane, methyl ethyl ether, 1,4-dioxane, tetrahydrofuran, benzene, toluene, xylene, mesityrene, durene, Aromatic hydrocarbons such as decalin; halogen-based solvents such as dichloromethane, chloroform, carbon tetrachloride, chlorobenzene, 1,2-dichlorobenzene, N, N'-dimethylformamide, N, N'-dimethylacetamide, N-methyl- Examples thereof include 2-pyrrolidone, dimethylsulfoxide, acetone, acetonitrile, benzonitrile, triethylamine and pyridine. These reaction solvents may be used alone or in combination of two or more. Further, as the solvent, a solvent in which an aromatic compound serving as a ligand and a metal salt can be dissolved is preferable.

The mixing temperature of the ligand compound and the metal-imparting agent is not particularly limited, but is preferably −10 ° C. or higher and 250 ° C. or lower, more preferably 0 ° C. or higher and 200 ° C. or lower, and further preferably 0 ° C. or higher and 150 ° C. or lower. It is as follows.

The mixing time of the aromatic compound and the metal salt is not particularly limited, but is preferably 1 minute or more and 1 week or less, more preferably 3 minutes or more and 24 hours or less, and further preferably 10 minutes or more and 12 hours or less. .. The mixing temperature and mixing time are preferably adjusted in consideration of the types of the aromatic compound and the metal salt.

The produced metal complex can be taken out from the solvent by selecting and applying a suitable method from known recrystallization methods, reprecipitation methods, chromatography methods and the like. At this time, a plurality of the above methods are combined. You may. Depending on the type of the solvent, the formed metal complex may be precipitated. In this case, the precipitated cobalt complex may be separated by filtration or the like, and then washed, dried or the like.

（式（２）中、Ｑ^２は窒素含有複素環またはハロゲン原子である。Ｒ^４、Ｒ^５、Ｒ^６はそれぞれ独立に水素原子または一価の置換基である。複数のＱ^２、Ｒ^４、Ｒ^５、Ｒ^６はそれぞれ同じでも異なっていてもよい。） Next, the aromatic compound represented by the formula (2) will be described. The magnesium air electrode of the present invention preferably has a ligand and a metal, and the ligand contains a metal complex which is an aromatic compound represented by the formula (2).

(In formula (2), Q ² is a nitrogen-containing heterocycle or halogen atom. R ⁴ , R ⁵ , and R ⁶ are independently hydrogen atoms or monovalent substituents. Multiple Q ² , R ⁴ , R ⁵ and R ⁶ may be the same or different, respectively.)

Specific examples and preferable examples of R ⁴ , R ⁵ , and R ⁶ in the formula (2) are the same as those of R ¹ , R ² , and R ³ , respectively.

Preferred examples and specific examples Q ² 'in the formula (2), of the Q ^1, is the same as the structure for limiting the nitrogen-containing heterocyclic ring or a halogen atom.
That, Q ² is a fluorine atom, a chlorine atom, a bromine atom, an iodine atom or a nitrogen-containing heterocycle. Examples of the nitrogen-containing heterocycle include a pyridine ring, a pyrimidine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, a phenanthroline ring, a bipyridine ring, a dipyrrolyl methylene ring, a quinoline ring, an isoquinoline ring, an imidazole ring, a pyrazole ring, and an oxazole. Examples thereof include a ring, a thiazole ring, an oxadiazole ring, a thiaziazole ring, an azadiazole ring, an aclysin ring, and an N-alkylpyrrole ring, and a pyridine ring, a pyridazine ring, a pyrimidine ring, a phenanthroline ring, a bipyridine ring, and an imidazole ring are preferable. , Pyridine ring, pyridazine ring, pyrimidine ring are more preferable. Halogen atom in Q ² is a chlorine atom or a bromine atom.

Preferred forms of the aromatic compound represented by the formula (2) are A5 to A13, A15, A20, A22 and A24 to 26.

The aromatic compound represented by the formula (2) can be synthesized by combining generally known reactions, and is not particularly limited. For example, it can be suitably produced by the scheme of the formula (5) shown below.

式（５）に一形態を示す。式（５）の詳細は、式（４）においてＱ^２が窒素含有複素環またはハロゲン原子である場合と同様である。

One form is shown in the formula (5). The details of the formula (5) are the same as in the case where Q ² is a nitrogen-containing heterocycle or a halogen atom in the formula (4).

（式（３）中、Ｑ^３は窒素含有複素環またはハロゲン原子である。Ｒ^７、Ｒ^８、Ｒ^９はそれぞれ独立に水素原子または一価の置換基である。複数のＱ^３、Ｒ^７、Ｒ^８、Ｒ^９はそれぞれ同じでも異なっていてもよい。式（３）中、電荷の記載は省略してある。） A metal complex having a ligand and a metal and the ligand being an aromatic compound represented by the formula (3) will be described. The electrode for a magnesium-air battery of the present invention preferably has a ligand and a metal, and the ligand contains a metal complex which is an aromatic compound represented by the formula (3).

(In formula (3), Q ³ is a nitrogen-containing heterocycle or a halogen atom. R ⁷ , R ⁸ and R ⁹ are independently hydrogen atoms or monovalent substituents. Multiple Q ³ and R ⁷ , R ⁸ and R ⁹ may be the same or different, respectively. In the equation (3), the description of the charge is omitted.)

The specific examples and preferable examples of R ⁷ , R ⁸ , and R ⁹ in the formula (3) are the same as those of R ¹ , R ² , and R ³ , respectively, and the specific examples and preferable examples of Q ³ are the same as those of Q ^2. Is.

In the formula (3), the description of the electric charge is omitted as in the above formula (1), N in the formula (3) may have a proton, and the phenolate in the formula (1) has a proton. It may have a phenolic structure.

In the structure and specific example of the metal complex of this embodiment, among the metal complexes having the aromatic compound represented by the formula (1) as a ligand, the structure of Q1 in the formula (1) is a nitrogen-containing heterocycle or a nitrogen-containing heterocycle. It is the same as the one limited to halogen atoms.

Preferred forms of the metal complex represented by the formula (3) are Co-A5, Co-A6, Co-A7, Co-A8, Fe-A5, Fe-A6, Fe-A7, Fe-A8, Co2-. A9, Co2-A10, Fe2-A11, FeCo-A12, Co-A9, Co-A10, Fe-A11, Co-A12, Co-A20, Fe-A20, Co2-A22, Fe2-A22, Co2-A24, Co2-A25 and Co2-A26.

The metal complex of this embodiment can be synthesized by the same production method as the metal complex having the aromatic compound represented by the above formula (1) as a ligand.

(Magnesium air battery)
The magnesium air battery of the present embodiment uses the electrode of the present invention as a positive electrode, and includes a negative electrode containing one or more negative electrode active materials selected from the group consisting of magnesium alone and a magnesium alloy, and an electrolytic solution.

FIG. 1 is a schematic cross-sectional view illustrating one embodiment of the magnesium-air battery according to the present embodiment.
The magnesium-air battery 1 shown here contains the positive electrode catalyst layer 11 including the electrode catalyst, the positive electrode current collector 12, the negative electrode active material layer 13 containing the negative electrode active material, the negative electrode current collector 14, the electrolytic solution 15, and the like. A container (not shown) is provided.
The positive electrode current collector 12 is arranged in contact with the positive electrode catalyst layer 11, and a positive electrode is formed by these. Further, the negative electrode current collector 14 is arranged in contact with the negative electrode active material layer 13, and the negative electrode is formed by these. Further, a positive electrode terminal (lead wire) 120 is connected to the positive electrode current collector 12, and a negative electrode terminal (lead wire) 140 is connected to the negative electrode current collector 14.
The positive electrode catalyst layer 11 and the negative electrode active material layer 13 are arranged so as to face each other, and the electrolytic solution 15 is arranged between them so as to come into contact with them.
The magnesium-air battery according to the present embodiment is not limited to the one shown here, and a part of the configuration may be changed as necessary.

(Positive electrode catalyst layer)
The positive electrode catalyst layer of the present invention contains a metal complex as an electrode catalyst, but may contain other electrode catalysts in addition to these. Further, the electrode preferably contains a conductive material and a binder. The conductive material may be any material that can improve the conductivity of the electrode, and conductive carbon is preferable.

Examples of the conductive carbon include "NORIT" (manufactured by NORIT), "Ketchen Black" (manufactured by Lion), "Vulcan" (manufactured by Cabot), "Black Pearls" (manufactured by Cabot), and "acetylene black". Carbon black such as (manufactured by Denki Kagaku Kogyo Co., Ltd.) (trade names); fullerenes such as C60 and C70; carbon fibers such as carbon nanotubes, multi-wall carbon nanotubes, double-wall carbon nanotubes, single-wall carbon nanotubes, and carbon nanohorns. Graphene and graphene oxide can be exemplified, and carbon black is preferable.

The conductive carbon may be used in combination with a conductive polymer such as polypyrrole or polyaniline.

The binder is for adhering an electrode catalyst, a conductive material, and the like to each other. For example, polytetrafluoroethylene (PTFE), polyethylene oxide (PEO), polyethylene glycol (PEG), polyvinylidene fluoride (PVDF), polyvinylidene fluoride (PVDF), and polyvinylidene fluoride (PVDF). Vinylidene fluoride-propylene hexafluoride copolymer (PVDF-H), carboxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), polyvinylidene acid (PAA), polyvinyl alcohol (PVA), polyacrylic nitrile (PAN), Examples thereof include polyimide (PI) and Nafion (registered trademark), such as polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyvinylidene fluoride-propylene hexafluoride copolymer (PVDF-H), and Nafion (registered). Trademark) is preferred.

The upper limit of the blending amount of the metal complex with respect to the total amount of the metal complex and the conductive material is preferably 90% by weight, more preferably 50% by weight, further preferably 30% by weight, and 20% by weight. Especially preferable. As the lower limit value, 0.1% by weight is preferable, 0.5% by weight is more preferable, 1.0% by weight is further preferable, and 2.0% by weight is particularly preferable.

The upper limit of the blending amount of the binder is 300 parts by mass, more preferably 200 parts by mass, and particularly preferably 150 parts by mass with respect to 1 part by mass of the electrode catalyst. As the lower limit value, 0.1 parts by mass is preferable, and 0.5 parts by mass is more preferable.

In the positive electrode catalyst layer, one type of each component such as the other electrode catalyst, the conductive material, and the binder may be used alone, or two or more types may be used in combination.

(Positive current collector)
Since the positive electrode current collector has a role of supplying an electric current to the electrode catalyst, the material thereof may be conductive. Examples of preferable positive electrode current collectors include metal plates, metal foils, metal meshes, metal sintered bodies, carbon papers, and carbon cloths.
Examples of the metal in the metal mesh and the metal sintered body include a single metal such as nickel, copper, chromium, iron, and titanium; and alloys containing two or more of these metals, such as nickel, copper, and stainless steel (iron-nickel). -Chrome alloy) is preferred.

(Positive electrode)
The positive electrode has a positive electrode catalyst layer and a positive electrode current collector. A gas diffusion layer may be sandwiched between the positive electrode catalyst layer and the positive electrode current collector. The positive electrode is formed by mixing the electrode catalyst, the conductive material, the binder, and the like, arranging the mixture on the positive electrode current collector described later, and then heat-pressing the positive electrode catalyst layer on the positive electrode current collector. Is formed and can be manufactured. The temperature of the hot press is not particularly limited, but is preferably set near the glass transition temperature of the binder to be used. Further, the temperature of the hot press is not particularly limited and can be set arbitrarily. Further, if necessary, the mixture can be produced by dispersing it in a solvent, applying it on a positive electrode current collector, and then drying it. As the solvent, the solvent exemplified as the reaction solvent can be used.

(Negative electrode)
As the negative electrode in the present embodiment, one or more selected from the group consisting of elemental magnesium and magnesium compounds can be used as the negative electrode active material. Examples of the magnesium compound include magnesium alloys and the like.

As a magnesium alloy, it is an alloy containing magnesium as a main component, and is, for example, a magnesium-aluminum alloy, a magnesium-aluminum-zinc alloy, a magnesium-zyrosine alloy, a magnesium-zinc-zirconium alloy, a magnesium-rare earth element alloy. , And a flame-retardant magnesium alloy obtained by adding a few percent of calcium to the alloy.

The shape of the negative electrode is not particularly limited, and any of plate-like, granular, powder-like, and gel-like shapes may be used.

The negative electrode current collector 14 may be the same as the positive electrode current collector 12.

(Electrolytic solution)
As the electrolytic solution, an electrolytic solution in which an electrolyte is dissolved in a solvent can be used. Water is preferable as the solvent because ions are easily ionized.

Examples of the electrolyte include sodium chloride, potassium chloride, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium hydrogen carbonate, potassium carbonate, potassium hydrogen carbonate, sodium formate, potassium formate, sodium acetate, potassium acetate, trisodium phosphate, and the like. Examples thereof include dipotassium hydrogen phosphate, potassium dihydrogen phosphate, trisodium phosphate, disodium hydrogen phosphate, sodium dihydrogen phosphate, sodium borate, potassium sulfate, and sodium sulfate. More preferably, sodium chloride, potassium chloride, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium hydrogen carbonate, potassium carbonate, potassium hydrogen carbonate, and more preferably sodium chloride, sodium carbonate, sodium hydrogen carbonate. The electrolyte may be anhydrous or hydrated.

One type of each of the electrolytes may be used alone, or two or more types may be used in combination.

The concentration of the electrolyte in the electrolytic solution can be arbitrarily set depending on the usage environment of the magnesium-air battery, but is preferably 1 to 99% by mass, more preferably 5 to 60% by mass, and 5 to 5%. It is more preferably 40% by mass.

Polyvalent carboxylic acid salts such as citrate, succinate and tartrate may be added to the electrolytic solution.

Further, the electrolytic solution may be used as a gel-like electrolyte in which a water-absorbent polymer such as polyacrylic acid is absorbed.

<Other configurations>
The container contains the positive electrode catalyst layer 11, the positive electrode current collector 12, the negative electrode active material layer 13, the negative electrode current collector 14, and the electrolytic solution 15. Examples of the material of the container include resins such as polystyrene, polyethylene, polypropylene, polyvinyl chloride, and ABS resin, and metals that do not react with the contained material such as the positive electrode catalyst layer 11.

The magnesium-air battery 1 may be provided with an oxygen diffusion film separately. The oxygen diffusion film is preferably provided on the outside of the positive electrode current collector 12 (opposite side of the positive electrode catalyst layer 11). By doing so, oxygen (air) is preferentially supplied to the positive electrode catalyst layer 11 via the oxygen diffusion film.
The oxygen diffusion film may be any film that can suitably permeate oxygen (air), and a resin non-woven fabric or a porous film can be exemplified. Examples of the resin include polyolefins such as polyethylene and polypropylene; polytetrafluoroethylene, Fluororesin such as polyvinylidene fluoride can be exemplified.

In the magnesium-air battery 1, a separator may be provided between them in order to prevent a short circuit due to contact between the positive electrode and the negative electrode.
The separator may be made of an insulating material capable of moving the electrolytic solution 15, and a non-woven fabric made of a resin or a porous film can be exemplified. Examples of the resin include polyolefins such as polyethylene and polypropylene; polytetrafluoroethylene, Fluororesin such as polyvinylidene fluoride can be exemplified. When the electrolytic solution 15 is used as an aqueous solution, it is preferable to use a hydrophilic resin as the resin.

The shape of the magnesium-air battery of the present invention is not particularly limited, and examples thereof include a coin type, a button type, a sheet type, a laminated type, a cylindrical type, a flat type, and a square type.

The magnesium-air battery of the present embodiment is useful, for example, for a large-sized power source such as a power source for an electric vehicle or a power source for home use, and is also useful as a small power source for a mobile device such as a mobile phone or a portable personal computer.

Hereinafter, the present invention will be described in more detail with reference to specific examples.

[Synthesis Example 1]
<Synthesis of cobalt complex MC1>
As shown in the following reaction formula, compound 3 was synthesized via compound 1 and compound 2, and then a cobalt complex MC1 was synthesized using compound 3 and a metal-imparting agent.

（式中、Ｂｏｃはｔｅｒｔ−ブトキシカルボニル基であり、ｄｂａはジベンジリデンアセトンである。） (Synthesis of Compound 1)

(In the formula, Boc is a tert-butoxycarbonyl group and dba is dibenzylideneacetone.)

After setting the inside of the reaction vessel to an argon gas atmosphere, 3.94 g (6.00 mmol) of 2,9- (3'-bromo-5'-tert-butyl-2'-methoxyphenyl) -1,10-phenanthroline ( Synthesized according to the description of Tetrahedron., 1999, 55, 8377.) 3.17 g (15.0 mmol) 1-N-Boc-pyrrole-2-boronic acid, 0.14 g (0.15 mmol) Tris (0.15 mmol) Benzylideneacetone) dipalladium, 0.25 g (0.60 mmol) of 2-dicyclohexylphosphino-2', 6'-dimethoxybiphenyl and 5.53 g (26.0 mmol) of potassium phosphate, 200 mL of dioxane and 20 mL. Was added to a mixed solvent with water to dissolve the mixture, and the mixture was stirred at 60 ° C. for 6 hours. After completion of the reaction, the mixture was allowed to cool, distilled water and chloroform were added, and the organic layer was extracted. The resulting organic layer was concentrated to give a black residue. This was purified by a silica gel column using chloroform as a developing solvent to obtain Compound 1. The identification data of the obtained compound 1 is shown below.

^{1 1} H-NMR (300 MHz, CDCl ₃ ): δ (ppm) = 1.34 (s, 18H), 1.37 (s, 18H), 3.30 (s, 6H), 6.21 (m, 2H) ), 6.27 (m, 2H), 7.37 (m, 2H), 7.41 (s, 2H), 7.82 (s, 2H), 8.00 (s, 2H), 8.19 (D, J = 8.6Hz, 2H), 8.27 (d, J = 8.6Hz, 2H).

（式中、Ｂｏｃはｔｅｒｔ−ブトキシカルボニル基である。） (Synthesis of Compound 2)

(In the formula, Boc is a tert-butoxycarbonyl group.)

After making the inside of the reaction vessel a nitrogen gas atmosphere, 0.904 g (1.08 mmol) of Compound 1 was dissolved in 10 mL of anhydrous dichloromethane. While cooling the obtained dichloromethane solution to −78 ° C., 8.8 mL (8.8 mmol) of a 1.0 M dichloromethane solution of boron tribromide was slowly added dropwise thereto. After the dropping, the mixture was stirred as it was for 10 minutes, and left with further stirring until it reached room temperature. After 3 hours, the reaction solution was cooled to 0 ° C., saturated aqueous sodium hydrogen carbonate solution was added, chloroform was added for extraction, and the organic layer was concentrated. The obtained brown residue was purified by a silica gel column using chloroform as a developing solvent to obtain Compound 2. The identification data of the obtained compound 2 is shown below.

^{1 1} H-NMR (300 MHz, CDCl ₃ ): δ (ppm) = 1.40 (s, 18H), 6.25 (m, 2H), 6.44 (m, 2H), 6.74 (m, 2H) ), 7.84 (s, 2H), 7.89 (s, 2H), 7.92 (s, 2H), 8.35 (d, J = 8.4Hz, 2H), 8.46 (d, J = 8.4Hz, 2H), 10.61 (s, 2H), 15.88 (s, 2H).

(Synthesis of Compound 3)

In the reaction vessel, 0.061 g (0.10 mmol) of Compound 2 and 0.012 g (0.11 mmol) of benzaldehyde were dissolved in 5 mL of propionic acid and heated at 140 ° C. for 7 hours. Then, propionic acid was distilled off from the obtained reaction solution, and the obtained black residue was purified by a silica gel column using a solvent in which chloroform and methanol were mixed at a volume ratio of 10: 1 as a developing solvent. Compound 3 was obtained. The identification data of the obtained compound 3 is shown below.

^{1 1} H-NMR (300 MHz, CDCl ₃ ): δ (ppm) = 1.49 (s, 18H), 6.69 (d, J = 4.8 Hz, 2H), 7.01 (d, J = 4. 8Hz, 2H), 7.57 (m, 5H), 7.90 (s, 4H), 8.02 (s, 2H), 8.31 (d, J = 8.1Hz, 2H), 8.47 (D, J = 8.1Hz, 2H).

（式中、Ａｃはアセチル基であり、Ｍｅはメチル基である。） (Synthesis of cobalt complex MC1)

(In the formula, Ac is an acetyl group and Me is a methyl group.)

After setting the inside of the reaction vessel to a nitrogen gas atmosphere, 3 mL of methanol and 3 mL of chloroform containing 0.045 g (0.065 mmol) of Compound 3 and 0.040 g (0.16 mmol) of cobalt acetate tetrahydrate were added. The mixed solution was mixed and stirred for 5 hours while heating at 80 ° C. The resulting solution was concentrated to dryness to give a blue solid. This was washed with water to obtain a cobalt complex MC1. In the cobalt complex MC1 in the reaction formula, "OAc" indicates that 1 equivalent of acetate ion is present as a counter ion. The identification data of the obtained cobalt complex MC1 is shown below.
ESI-MS [M.] ⁺ : m / z = 866.0

０．５４７ｇの２，６−ジブロモ−４−ｔｅｒｔ−ブチルアニソール、０．８４４ｇの１−Ｎ−Ｂｏｃ−ピロール−２−ボロン酸、０．１３８ｇのトリス（ベンジリデンアセトン）ジパラジウム、０．２４７ｇの２−ジシクロヘキシルホスフィノ−２’，６’−ジメトキシビフェニル、５．５２７ｇのリン酸カリウムを２００ｍＬのジオキサンと２０ｍＬの水の混合溶媒に溶解し、６０℃にて９時間攪拌した。反応終了後、放冷して蒸留水、クロロホルムを加えて、有機層を抽出した。得られた有機層を濃縮して、黒い残渣を得た。これを、シリカゲルカラムを用いて精製し、化合物（Ｄ）を得た。
^１Ｈ−ＮＭＲ（３００ＭＨｚ，ＣＤＣｌ_３）δ１．３０（ｓ，１８Ｈ），１．３１（ｓ，９Ｈ），３．１９（ｓ，３Ｈ），６．１９（ｍ，２Ｈ），６．２５（ｍ，２Ｈ），７．２２（ｓ，２Ｈ），７．３８（ｍ，２Ｈ）． [Synthesis Example 2]
<Synthesis of cobalt complex MC2>
As shown in the following reaction formula, the compound (F) was synthesized via the compound (D) and the compound (E), and then the cobalt complex MC2 was synthesized by using the compound (F) and the metal imparting agent.

0.547 g of 2,6-dibromo-4-tert-butylanisole, 0.844 g of 1-N-Boc-pyrrole-2-boronic acid, 0.138 g of tris (benzylideneacetone) dipalladium, 0.247 g 2-Dicyclohexylphosphino-2', 6'-dimethoxybiphenyl, 5.527 g of potassium phosphate was dissolved in a mixed solvent of 200 mL of dioxane and 20 mL of water, and the mixture was stirred at 60 ° C. for 9 hours. After completion of the reaction, the mixture was allowed to cool, distilled water and chloroform were added, and the organic layer was extracted. The obtained organic layer was concentrated to give a black residue. This was purified using a silica gel column to obtain compound (D).
^{1 1} H-NMR (300 MHz, CDCl ₃ ) δ1.30 (s, 18H), 1.31 (s, 9H), 3.19 (s, 3H), 6.19 (m, 2H), 6.25 ( m, 2H), 7.22 (s, 2H), 7.38 (m, 2H).

窒素雰囲気下で０．４５３ｇの化合物（Ｄ）を１５ｍＬの無水ジクロロメタンに溶解させた。ジクロロメタン溶液をドライアイス／アセトンバスで−７８℃に冷却しながら、５．４ｍＬの三臭化ホウ素（１．０Ｍジクロロメタン溶液）をゆっくり滴下した。滴下後、１０分間そのまま攪拌させた後、ドライアイス／アセトンバスを取り除き、室温まで攪拌させながら放置した。１時間後、飽和ＮａＨＣＯ３水溶液を加えて中和し、クロロホルムを加えて３回抽出した。得られた有機層を濃縮して、得られた黒色の残渣を、シリカゲルで精製し、化合物（Ｅ）を得た。
^１Ｈ−ＮＭＲ（３００ＭＨｚ，ＣＤＣｌ_３）δ１．３４（ｓ，９Ｈ），６．３５（ｍ，２Ｈ），６．４０（ｓ，１Ｈ），６．５５（ｍ，２Ｈ），６．９３（ｍ，２Ｈ），７．３６（ｓ，２Ｈ），９．１５（ｓ，２Ｈ）． Compound (E) was synthesized according to the following reaction formula.

0.453 g of compound (D) was dissolved in 15 mL anhydrous dichloromethane under a nitrogen atmosphere. While cooling the dichloromethane solution to −78 ° C. in a dry ice / acetone bath, 5.4 mL of boron tribromide (1.0 M dichloromethane solution) was slowly added dropwise. After the dropping, the mixture was stirred as it was for 10 minutes, the dry ice / acetone bath was removed, and the mixture was left to stand while stirring to room temperature. After 1 hour, saturated aqueous NaHCO3 solution was added for neutralization, chloroform was added, and the mixture was extracted 3 times. The obtained organic layer was concentrated, and the obtained black residue was purified with silica gel to obtain compound (E).
^{1 1} H-NMR (300 MHz, CDCl ₃ ) δ1.34 (s, 9H), 6.35 (m, 2H), 6.40 (s, 1H), 6.55 (m, 2H), 6.93 ( m, 2H), 7.36 (s, 2H), 9.15 (s, 2H).

０．０５１ｇの化合物（Ｅ）と０．０１９ｇのベンズアルデヒドを２０ｍＬのプロピオン酸に溶解させ、１４０℃で７時間加熱した。その後、プロピオン酸を留去して、得られた黒い残渣をシリカゲルで精製して、化合物（Ｆ）を得た。
^１Ｈ−ＮＭＲ（３００ＭＨｚ，ＣＤＣｌ_３）δ１．３８（ｓ，１８Ｈ），６．５８（ｄ，Ｊ＝３．８Ｈｚ，４Ｈ），６．９２（ｄ，Ｊ＝３．８Ｈｚ，４Ｈ），７．４９（ｍ，１０Ｈ），７．７１（ｓ，４Ｈ），１２．７５（ｂｒ，４Ｈ）． The macrocycle compound (F) was synthesized according to the following reaction formula.

0.051 g of compound (E) and 0.019 g of benzaldehyde were dissolved in 20 mL of propionic acid and heated at 140 ° C. for 7 hours. Then, propionic acid was distilled off, and the obtained black residue was purified with silica gel to obtain compound (F).
^{1 1} H-NMR (300MHz, CDCl ₃ ) δ1.38 (s, 18H), 6.58 (d, J = 3.8Hz, 4H), 6.92 (d, J = 3.8Hz, 4H), 7 .49 (m, 10H), 7.71 (s, 4H), 12.75 (br, 4H).

窒素雰囲気下において、０．０５７ｇの大環状化合物（Ｆ）と０．０４７ｇの酢酸コバルト４水和物を含んだメタノール４ｍｌ、クロロホルム６ｍｌの混合溶液を、８０℃に加熱しながら５時間攪拌した。得られた溶液を濃縮乾固させると紫色固体を得た。これを水で洗浄することにより、コバルト錯体ＭＣ２を得た。
ＥＳＩ−ＭＳ［Ｍ・］＋：ｍ／ｚ＝８４６．０ The cobalt complex MC2 was synthesized according to the following reaction formula.

Under a nitrogen atmosphere, a mixed solution of 4 ml of methanol and 6 ml of chloroform containing 0.057 g of the macrocycle compound (F) and 0.047 g of cobalt acetate tetrahydrate was stirred for 5 hours while heating at 80 ° C. The obtained solution was concentrated to dryness to obtain a purple solid. This was washed with water to obtain a cobalt complex MC2.
ESI-MS [M ・] +: m / z = 846.0

窒素雰囲気下において０．４７６ｇの塩化コバルト６水和物と０．４１２gの４―ｔｅｒｔ-ブチル−２，６−ジホルミルフェノールを含んだ１０ｍｌエタノール溶液を５０ｍｌのナスフラスコに入れ、室温にて攪拌した。この溶液に０．２１６ｇのｏ−フェニレンジアミンを含んだ５ｍｌエタノール溶液を徐々に添加した。上記混合物を２時間還流することにより茶褐色沈殿が生成した。この沈殿を濾取し、乾燥することでコバルト錯体ＭＣ３を得た（収量０．４６５ｇ：収率６３％）。 [Synthesis Example 3]
<Synthesis of cobalt complex MC3>
The cobalt complex MC3 was synthesized according to the following reaction formula.

A 10 ml ethanol solution containing 0.476 g of cobalt chloride hexahydrate and 0.412 g of 4-tert-butyl-2,6-diformylphenol under a nitrogen atmosphere was placed in a 50 ml eggplant flask and stirred at room temperature. did. A 5 ml ethanol solution containing 0.216 g of o-phenylenediamine was gradually added to this solution. A brown precipitate was formed by refluxing the mixture for 2 hours. This precipitate was collected by filtration and dried to obtain a cobalt complex MC3 (yield 0.465 g: 63% yield).

窒素雰囲気下において０．４７６ｇの塩化コバルト６水和物と０．４６９gの３，５−ジ−ｔｅｒｔ−ブチル−２−ヒドロキシベンズアルデヒドを含んだ１０ｍｌエタノール溶液を５０ｍｌのナスフラスコに入れ、室温にて攪拌した。この溶液に０．２１６ｇのｏ−フェニレンジアミンを含んだ１０ｍｌエタノール溶液を徐々に添加した。上記混合物を２時間還流することにより茶褐色沈殿が生成した。この沈殿を濾取し、乾燥することでコバルト錯体ＭＣ４を得た（収量０．０８ｇ：収率７％）。 [Synthesis Example 4]
<Synthesis of cobalt complex MC4>

A 10 ml ethanol solution containing 0.476 g of cobalt chloride hexahydrate and 0.469 g of 3,5-di-tert-butyl-2-hydroxybenzaldehyde under a nitrogen atmosphere was placed in a 50 ml eggplant flask at room temperature. Stirred. A 10 ml ethanol solution containing 0.216 g of o-phenylenediamine was gradually added to this solution. A brown precipitate was formed by refluxing the mixture for 2 hours. This precipitate was collected by filtration and dried to obtain a cobalt complex MC4 (yield 0.08 g: yield 7%).

[Synthesis Example 5]
<Synthesis of cobalt complex MC5>
As shown in the following reaction formula, the compound 10 was synthesized via the compounds 4 to 9, and then the cobalt complex MC5 was synthesized by using the compound 10 and the metal imparting agent.

(Synthesis of Compound 4)

250 g (1.664 mol) of 4-tert-butylphenol, 420 ml of chloroform, and 420 ml of carbon tetrachloride were charged into a 3 L flask under a light-shielded argon stream, and a bromine / chloroform solution [240 g (0.9) equal amount of bromine, 270 ml of chloroform] was charged therein. Was added dropwise at an internal temperature of 8 ± 2 ° C. over 1 hour. After completion of the dropping, the mixture was stirred overnight at room temperature. Concentration was carried out under reduced pressure to obtain an oil of compound 4 (372 g). Yield 97.5%.

(Synthesis of Compound 5)

Compound 4 (371 g), anhydrous potassium carbonate (335 g), and 5 L of acetone were charged into a 10 L flask under an argon stream, and 435 g of methyl iodide was added dropwise thereto over 30 minutes. After completion of the dropping, the mixture was stirred overnight at an internal temperature of 40 ° C. Filtration and vacuum distillation were carried out to obtain Compound 5 (355.8 g). Yield 90.3%.

(Synthesis of Compound 6)

Under an argon stream, 10 g of lithium and 102 ml of dehydrated diethyl ether were placed in a 2 L flask, and a diethyl ether solution of compound 5 [Compound 5: 158 g, dehydrated diethyl ether 1 L] was added dropwise over 30 minutes, followed by reflux for 1 hour. went. The mixture was cooled to room temperature to obtain a lithium solution. 12.52 g (0.08 mol) of 2,2'-bipyridyl and 1 L of dehydrated toluene were charged into a 5 L flask under an argon stream, and the lithiotized solution was added dropwise thereto over 40 minutes, and then reflux was performed for 45 hours. After cooling the internal temperature to 5 ° C., 300 ml of water was added dropwise, the liquid was separated, the aqueous phase was extracted with dichloromethane, the organic phases were combined, 50 g of manganese dioxide was added, and the mixture was stirred overnight. After filtration, the mixture was dehydrated with anhydrous sodium sulfate and concentrated under reduced pressure to obtain a crude product. Column purification was performed to obtain Compound 6 (6.245 g). Yield 16.2%.

(Synthesis of Compound 7)

Compound 6 (6.145 g, 12.79 mmol) and 400 ml of dehydrated dichloromethane were charged into a 1 L flask under a light-shielded argon stream, 6.2 g of bromine was added, and reflux was carried out for 20 hours. Since the monobromo form remained, bromine was added and refluxed for another 20 hours. After completion of the reaction, neutralization, analysis and column purification were carried out to obtain Compound 7 (7.334 g). Yield 89.8%.

（式中、Ｂｏｃはｔｅｒｔ−ブトキシカルボニル基であり、ｄｂａはジベンジリデンアセトンである。） (Synthesis of Compound 8)

(In the formula, Boc is a tert-butoxycarbonyl group and dba is dibenzylideneacetone.)

After setting the inside of the reaction vessel to an argon gas atmosphere, 0.50 g (0.77 mmol) of compound 7, 0.41 g (1.9 mmol) of 1-N-Boc-pyrrole-2-boronic acid, 0.018 g (0). .02 mmol) tris (benzylideneacetone) dipalladium, 0.032 g (0.08 mmol) of 2-dicyclohexylphosphino-2', 6'-dimethoxybiphenyl and 0.72 g (3.1 mmol) of potassium phosphate. , 25 mL of dioxane and 2.5 mL of water were added to the mixed solvent to dissolve the mixture, and the mixture was stirred at 60 ° C. for 6 hours. After completion of the reaction, the mixture was allowed to cool, distilled water and chloroform were added, and the organic layer was extracted. The resulting organic layer was concentrated to give a black residue. This was purified by a silica gel column using chloroform as a developing solvent to obtain Compound 8. The identification data of the obtained compound 8 is shown below.

^{1 1} H-NMR (300 MHz, CDCl ₃ ): δ (ppm) = 1.34 (s, 18H), 1.37 (s, 18H), 3.30 (s, 6H), 6.21 (m, 2H) ), 6.27 (m, 2H), 7.37 (m, 2H), 7.41 (s, 2H), 7.82 (s, 2H), 8.00 (s, 2H), 8.19 (D, J = 8.6Hz, 2H), 8.27 (d, J = 8.6Hz, 2H).

（式中、Ｂｏｃはｔｅｒｔ−ブトキシカルボニル基である。） (Synthesis of Compound 9)

(In the formula, Boc is a tert-butoxycarbonyl group.)

After creating a nitrogen gas atmosphere in the reaction vessel, 0.28 g (0.43 mmol) of Compound 8 was dissolved in 10 mL of anhydrous dichloromethane. While cooling the obtained dichloromethane solution to −20 ° C., 3.46 mL (3.46 mmol) of a 1.0 mol / L dichloromethane solution of boron tribromide was slowly added dropwise thereto. After the dropping, the mixture was stirred as it was for 10 minutes, and left with further stirring until it reached room temperature. After 3 hours, the reaction solution was cooled to 0 ° C., saturated aqueous sodium hydrogen carbonate solution was added, chloroform was added for extraction, and the organic layer was concentrated. The obtained brown residue was purified by a silica gel column using chloroform as a developing solvent to obtain Compound 9. The identification data of the obtained compound 9 is shown below.

^{1 1} H-NMR (300 MHz, CDCl ₃ ): δ (ppm) = 1.40 (s, 18H), 6.25 (m, 2H), 6.44 (m, 2H), 6.74 (m, 2H) ), 7.84 (s, 2H), 7.89 (s, 2H), 7.92 (s, 2H), 8.35 (d, J = 8.4Hz, 2H), 8.46 (d, J = 8.4Hz, 2H), 10.61 (s, 2H), 15.88 (s, 2H).

(Synthesis of Compound 10)

In the reaction vessel, 80 mg (0.13 mmol) was dissolved in 150 mL of propionic acid and heated to 90 ° C. After adding 25 mL of propionic acid in which 14 mg (0.13 mmol) of benzaldehyde was dissolved, the mixture was heated to 140 ° C. and stirred for 3 hours. Propionic acid was distilled off from the obtained reaction solution, and the obtained black residue was purified by a silica gel column using a solvent in which chloroform and methanol were mixed at a volume ratio of 10: 1 as a developing solvent, and the compound 10 was purified. Got The identification data of the obtained compound 10 is shown below.

^{1 1} H-NMR (300 MHz, CDCl ₃ ): δ (ppm) = 1.49 (s, 18H), 6.69 (d, J = 4.8 Hz, 2H), 7.01 (d, J = 4. 8Hz, 2H), 7.57 (m, 5H), 7.90 (s, 4H), 8.02 (s, 2H), 8.31 (d, J = 8.1Hz, 2H), 8.47 (D, J = 8.1Hz, 2H).

(Synthesis of cobalt complex MC5)

After setting the inside of the reaction vessel to a nitrogen gas atmosphere, 2 mL of methanol and 2 mL of chloroform containing 8.7 mg (1.3 μmol) of compound 10 and 1.3 mg (5.2 μmol) of cobalt acetate tetrahydrate were added. The mixed solution was mixed and stirred for 2 hours while heating at 60 ° C. The resulting solution was concentrated to dryness to give a blue solid. This was washed with water to obtain a cobalt complex MC5. In the cobalt complex MC5 in the reaction formula, "OAc" indicates that 1 equivalent of acetate ion is present as a counter ion.

アルゴン雰囲気下、２００ｍＬの３つ口ナス形フラスコに、4-tert-Butylanisole １０．１ｇ（６１．２ｍｍｏｌ)と、脱水ジクロロメタン８５ｍＬとを加え、臭素７．４８ｍＬ（１５３ｍｍｏｌ）を１０分かけて滴下した。室温で１１時間撹拌した。
反応液にNa₂SO₃水溶液を加え、クロロホルム抽出にて水と飽和食塩水で洗い、硫酸ナトリウムで乾燥、ろ過、濃縮して無色液体の1,3-dibromo-5-tert-butyl-2-methoxybenzeneを１９．８ｇ（収率１００％)得た。 [Synthesis Example 6]
<Synthesis of cobalt complex MC6>

In an argon atmosphere, 10.1 g (61.2 mmol) of 4-tert-Butylanisole and 85 mL of dehydrated dichloromethane were added to a 200 mL three-necked eggplant-shaped flask, and 7.48 mL (153 mmol) of bromine was added dropwise over 10 minutes. .. The mixture was stirred at room temperature for 11 hours.
Add Na ₂ SO ₃ aqueous solution to the reaction solution, wash with water and saturated saline by chloroform extraction, dry with sodium sulfate, filter, concentrate and concentrate 1,3-dibromo-5-tert-butyl-2-, a colorless liquid. 19.8 g (yield 100%) of methoxybenzene was obtained.

（以下式中、Ｂｏｃはｔｅｒｔ−ブトキシカルボニル基である）
アルゴン雰囲気下、２００ｍＬの３つ口ナス形フラスコに、1-tert-butoxycarbonyl-2-pyrrolilboronic acid １．８８ｇ（８．７２ｍｍｏｌ）、炭酸ナトリウム２．７７ｇ（２６．２ｍｍｏｌ）およびテトラキス（トリフェニルホスフィン）パラジウム(0) ５０４ｍｇ （０．４３６ｍｍｏｌ)を入れた。別のフラスコに、アルゴン雰囲気下で、1,3-dibromo-5-tert-butyl-2-methoxybenzene３．０１ｇ（８．７２ｍｍｏｌ）1,4-dioxane ８０ｍＬおよび水５ｍＬを混合し、混合液を得た。該混合液を、先の3つ口ナス形フラスコに、室温で加え、内温６０℃で４時間撹拌後、１００℃で１時間撹拌し、反応液を得た。
反応液をろ過、濃縮し、展開溶媒ヘキサン：クロロホルム＝４：１でシリカゲルカラムクロマトグラフィーを行い、無色液体の化合物１４を１．８０ｇ（収率４９．６％)得た。
¹H NMR (400 MHz, CDCl₃) δ7.48 (d, J = 2.8, 1H), 7.41-7.40 (m, 1H), 7.23 (d, J = 2.8, 1H), 6.25-6.20 (m, 2H), 3.40 (s, 3H), 1.30 (s, 9H), 1.26 (s, 9H); ¹³C NMR (100 MHz, CDCl₃) δ152.5, 149.6, 148.2, 129.9, 129.7, 129.4, 126.8, 122.5, 116.6, 114.3, 110.3, 83.6, 59.9, 34.6, 31.4, 27.4.

(In the following formula, Boc is a tert-butoxycarbonyl group)
1.88 g (8.72 mmol) of 1-tert-butoxycarbonyl-2-pyrrolilboronic acid, 2.77 g (26.2 mmol) of sodium carbonate and tetrakis (triphenylphosphine) in a 200 mL three-necked eggplant-shaped flask under an argon atmosphere. 504 mg (0.436 mmol) of palladium (0) was added. In another flask, 80 mL of 1,3-dibromo-5-tert-butyl-2-methoxybenzene3.01 g (8.72 mmol) 1,4-dioxane and 5 mL of water were mixed under an argon atmosphere to obtain a mixed solution. .. The mixed solution was added to the above three-necked eggplant-shaped flask at room temperature, stirred at an internal temperature of 60 ° C. for 4 hours, and then stirred at 100 ° C. for 1 hour to obtain a reaction solution.
The reaction solution was filtered and concentrated, and silica gel column chromatography was performed with a developing solvent of hexane: chloroform = 4: 1 to obtain 1.80 g (yield 49.6%) of compound 14 as a colorless liquid.
¹ H NMR (400 MHz, CDCl ₃ ) δ7.48 (d, J = 2.8, 1H), 7.41-7.40 (m, 1H), 7.23 (d, J = 2.8, 1H), 6.25-6.20 (m, 2H) ), 3.40 (s, 3H), 1.30 (s, 9H), 1.26 (s, 9H); ¹³ C NMR (100 MHz, CDCl ₃ ) δ152.5, 149.6, 148.2, 129.9, 129.7, 129.4, 126.8, 122.5 , 116.6, 114.3, 110.3, 83.6, 59.9, 34.6, 31.4, 27.4.

アルゴン雰囲気下、５０ｍＬの ２つ口ナス形フラスコに、化合物１４を１．００ｇ（２．４６ｍｍｏｌ）およびプロピオン酸９ｇを加え、１００℃で４時間撹拌し、その後、室温に戻し、反応溶液を得た。反応溶液を開放系にし、ベンズアルデヒド１２９．５ｍｇ（１．２３ｍｍｏｌ）を、プロピオン酸１ｇに溶解した溶液を加え、５時間還流した。
室温に冷ました反応溶液を濃縮し、展開溶媒ヘキサン：クロロホルム＝３：１ (ｖ/ｖ) でシリカゲルカラムクロマトグラフィーを行い、橙色固体の化合物１５を７９０ｍｇ(収率９１．８％) 得た。
¹H NMR (400 MHz, CDCl₃) δ9.41 (s, 2H), 7.51 (d, J = 2.0, 2H), 7.38-7.28 (m, 7H), 6.53 (t, J = 3.2, 2H), 6.07 (t, J = 3.2, 2H), 5.56 (s, 1H), 3.50 (s, 6H), 1.31 (s, 18H); ¹³C NMR (100 MHz, CDCl₃) δ149.5, 149.2, 142.0, 133.8, 129.0, 128.44, 128.37, 127.9, 127.4, 126.3, 117.8, 108.3, 107.5, 60.3, 44.6, 34.6, 31.3.

Under an argon atmosphere, 1.00 g (2.46 mmol) of compound 14 and 9 g of propionic acid were added to a 50 mL two-necked eggplant-shaped flask, and the mixture was stirred at 100 ° C. for 4 hours and then returned to room temperature to obtain a reaction solution. It was. The reaction solution was set to an open system, a solution prepared by dissolving 129.5 mg (1.23 mmol) of benzaldehyde in 1 g of propionic acid was added, and the mixture was refluxed for 5 hours.
The reaction solution cooled to room temperature was concentrated, and silica gel column chromatography was performed with the developing solvent hexane: chloroform = 3: 1 (v / v) to obtain 790 mg (yield 91.8%) of compound 15 as an orange solid.
^{1 1} H NMR (400 MHz, CDCl ₃ ) δ9.41 (s, 2H), 7.51 (d, J = 2.0, 2H), 7.38-7.28 (m, 7H), 6.53 (t, J = 3.2, 2H), 6.07 (t, J = 3.2, 2H), 5.56 (s, 1H), 3.50 (s, 6H), 1.31 (s, 18H); ¹³ C NMR (100 MHz, CDCl ₃ ) δ 149.5, 149.2, 142.0, 133.8, 129.0, 128.44, 128.37, 127.9, 127.4, 126.3, 117.8, 108.3, 107.5, 60.3, 44.6, 34.6, 31.3.

アルゴン雰囲気下、５０ｍＬの３つ口丸底フラスコに、化合物１５を２２０ ｍｇ(０．３１２ ｍｍｏｌ)、テトラキス（トリフェニルホスフィン）パラジウム(0) ５４．１ ｍｇ (０．４６８ ｍｍｏｌ)、脱水ＴＨＦ３ｍＬおよび2-pyridylznic bromideの０．５ｍｏｌ／Ｌ ＴＨＦ溶液１．８７ ｍＬ (０．９３７ ｍｍｏｌ)を加え、室温で２時間撹拌後、還流した。１３時間後、テトラキス（トリフェニルホスフィン）パラジウム(0) ２７．０ｍｇ (０．２３４ ｍｍｏｌ)、脱水ＴＨＦ２ｍＬおよび2-pyridylzinc bromideの０．５ｍｏｌ／Ｌ ＴＨＦ溶液０．９４ ｍＬ (０．４７ ｍｍｏｌ)を追加して、更に１２時間還流して、反応溶液を得た。
反応溶液を冷まし、飽和炭酸水素ナトリウム水溶液を加え、ろ過し、ろ液を濃縮してクロロホルム抽出により、水と飽和食塩水で洗浄し、硫酸ナトリウムで乾燥、ろ過、濃縮し、展開溶媒ヘキサン：クロロホルム＝３：１（ｖ／ｖ）でアルミナゲルカラムクロマトグラフィーを２回行い、赤色固体を２１７ｍｇ得た。
得られた赤色固体を真空乾燥し、ジクロロメタン２ｍＬに溶解した。これに、2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) ８６．６ｍｇ（０．３４３ ｍｍｏｌ）を、ジクロロメタン７ｍＬに溶解した溶液を、開放系室温で撹拌しながら５分かけて滴下して、反応溶液を得た。
反応溶液を、展開溶媒クロロホルム：酢酸エチル＝４：１（ｖ／ｖ）でシリカゲルカラムクロマトグラフィーにかけて、青色固体を８５．６ｍｇ得た。この成分はＮＭＲシグナルがブロードであった。
得られた青色固体を、ジクロロメタン抽出にて、濃塩酸、希塩酸および飽和炭酸水素ナトリウム水溶液で洗い、硫酸ナトリウムで乾燥、ろ過、濃縮して赤色固体の化合物１６を５８．０ｍｇ （収率２６．５％） 得た。また、副生成物としてピリジル基１ヶ所反応物である化合物１２を３２．２ｍｇ（収率１４．７％）得た。

In a 50 mL three-necked round-bottom flask under an argon atmosphere, 220 mg (0.312 mmol) of compound 15, 54.1 mg (0.468 mmol) of tetrakis (triphenylphosphine) palladium (0), 3 mL of dehydrated THF and 1.87 mL (0.937 mmol) of a 0.5 mol / L THF solution of 2-pyridylznic bromide was added, and the mixture was stirred at room temperature for 2 hours and then refluxed. After 13 hours, add 27.0 mg (0.234 mmol) of tetrakis (triphenylphosphine) palladium (0), 2 mL of dehydrated THF and 0.94 mL (0.47 mmol) of a 0.5 mol / L THF solution of 2-pyridylzinc bromide. In addition, reflux was performed for an additional 12 hours to obtain a reaction solution.
Cool the reaction solution, add saturated aqueous sodium hydrogen carbonate solution, filter, concentrate the filtrate, wash with water and saturated saline by chloroform extraction, dry, filter and concentrate with sodium sulfate, developing solvent hexane: chloroform. Alumina gel column chromatography was performed twice at 3: 1 (v / v) to obtain 217 mg of a red solid.
The obtained red solid was vacuum dried and dissolved in 2 mL of dichloromethane. A solution prepared by dissolving 86.6 mg (0.343 mmol) of 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) in 7 mL of dichloromethane was added to this solution in an open system at room temperature for 5 minutes with stirring. The mixture was added dropwise to obtain a reaction solution.
The reaction solution was subjected to silica gel column chromatography with the developing solvent chloroform: ethyl acetate = 4: 1 (v / v) to obtain 85.6 mg of a blue solid. The NMR signal of this component was broad.
The obtained blue solid was washed with concentrated hydrochloric acid, dilute hydrochloric acid and saturated aqueous sodium hydrogen carbonate solution by extraction with dichloromethane, dried over sodium sulfate, filtered and concentrated to obtain 58.0 mg (yield 26.5) of compound 16 as a red solid. %) Obtained. In addition, 32.2 mg (yield 14.7%) of compound 12, which is a reaction product at one pyridyl group, was obtained as a by-product.

The NMR data of compound 16 is shown below.
^{1 1} H NMR (400 MHz, CDCl ₃ ) δ8.73-8.71 (m, 2H), 7.89 (d, J = 2.8, 2H), 7.79 (d, J = 8.0, 2H), 7.71 (td, J = 7.6) , 2.0, 2H), 7.65 (d, J = 2.8, 2H), 7.59-7.57 (m, 2H), 7.48-7.45 (m, 3H), 7.25-7.22 (m, 2H), 6.93 (d, J = 4.4, 2H), 6.65 (d, J = 4.4, 2H), 3.48 (s, 6H), 1.31 (s, 18H); ¹³ C NMR (100 MHz, CDCl ₃ ) δ156.9, 153.9, 153.3, 149.6, 147.1, 141.5, 139.5, 138.1, 136.2, 134.1, 131.1, 129.2, 129.0, 128.7, 127.6, 127.0, 126.8, 124.9, 122.0, 118.8, 62.1, 34.6, 31.5.

The NMR data of Compound 12 is shown below.
^{1 1} H NMR (400 MHz, CDCl ₃ ) δ8.74 (d, J = 4.4, 1H), 8.17 (d, J = 2.8, 1H), 7.84 (d, J = 7.6, 1H), 7.76-7.69 (m) , 3H), 7.58-7.55 (m, 2H), 7.49-7.46 (m, 4H), 7.27-7.24 (m, 1H), 7.10 (d, J = 4.4, 1H), 6.76 (dd, J = 7.6, 4.4, 2H), 6.52 (d, J = 5.6, 1H), 3.78 (s, 3H), 3.47 (s, 3H), 1.44 (s, 9H), 1.29 (s, 9H); ¹³ C NMR (100 MHz) , CDCl ₃ ) δ159.7, 157.0, 154.6, 151.9, 149.6, 148.7, 147.6, 145.7, 145.1, 139.3, 138.4, 137.9, 136.1, 134.1, 132.2, 131.0, 130.6, 129.8, 128.7, 127.7, 127.5, 127.4, 126.8, 126.0, 125.0, 124.8, 122.7, 122.0, 118.1, 114.8, 62.1, 60.9, 34.9, 34.6, 31.7, 31.3.

アルゴン雰囲気下、３０ｍＬの３つ口丸底フラスコに、化合物１６を３０．０ｍｇ（０．４２８ ｍｍｏｌ）および脱水ジクロロメタン３ｍＬを加え、−２０ ℃で撹拌しながら三臭化ホウ素のジクロロメタン溶液１．０ｍｏｌ／Ｌを０．８６ｍＬ（０．８６ ｍｍｏｌ）５分かけて滴下した。内温の変化無し、色は赤から青に変化。３０分後、冷浴を外し５時間半撹拌した。反応溶液を０ ℃にして、水１ｍＬを滴下した。
反応溶液にクロロホルムを加え、抽出にて飽和炭酸水素ナトリウム水溶液、水および飽和食塩水で洗い、硫酸ナトリウムで乾燥、ろ過、濃縮後、展開溶媒クロロホルム：酢酸エチル＝４：１ （ｖ／ｖ）でシリカゲルカラムクロマトグラフィーを行い、紫色個体の化合物１３を１７．４ ｍｇ （収率６０．６％） 得た。
¹H NMR (400 MHz, CDCl₃) δ8.20 (br, 2H), 8.07 (d, J = 8.0, 2H), 7.93 (d, J = 2.8, 2H), 7.85 (d, J = 2.8, 2H), 7.58-7.44 (m, 7H), 7.03-6.97 (m, 4H), 6.69 (br, 2H); ¹³C NMR (100 MHz, CDCl₃) δ157.0, 156.0, 147.2, 141.1, 139.4, 138.8, 136.6, 131.8, 129.8 (br), 128.9, 127.6, 126.4, 126.1, 122.3 (br), 122.1, 121.5, 119.0, 115.9 (br), 34.4, 31.7.

Under an argon atmosphere, add 30.0 mg (0.428 mmol) of compound 16 and 3 mL of dehydrated dichloromethane to a 30 mL three-necked round-bottom flask, and 1.0 mol of a dichloromethane solution of boron tribromide with stirring at -20 ° C. / L was added dropwise over 0.86 mL (0.86 mmol) over 5 minutes. No change in internal temperature, color changes from red to blue. After 30 minutes, the cold bath was removed and the mixture was stirred for 5 and a half hours. The reaction solution was brought to 0 ° C., and 1 mL of water was added dropwise.
Add chloroform to the reaction solution, wash with saturated aqueous sodium hydrogen carbonate solution, water and saturated saline for extraction, dry with sodium sulfate, filter, concentrate, and then develop solvent chloroform: ethyl acetate = 4: 1 (v / v). Silica gel column chromatography was performed to obtain 17.4 mg (yield 60.6%) of Compound 13 as a purple solid.
^{1 1} H NMR (400 MHz, CDCl ₃ ) δ8.20 (br, 2H), 8.07 (d, J = 8.0, 2H), 7.93 (d, J = 2.8, 2H), 7.85 (d, J = 2.8, 2H) ), 7.58-7.44 (m, 7H), 7.03-6.97 (m, 4H), 6.69 (br, 2H); ¹³ C NMR (100 MHz, CDCl ₃ ) δ157.0, 156.0, 147.2, 141.1, 139.4, 138.8 , 136.6, 131.8, 129.8 (br), 128.9, 127.6, 126.4, 126.1, 122.3 (br), 122.1, 121.5, 119.0, 115.9 (br), 34.4, 31.7.

The results of DART-MS measurement of the obtained compound 13 are shown below. DART-MS (M / Z): found; 671.4. calcd; 671.3 (M + H) ⁺ .

アルゴン雰囲気下、３０ｍＬの３つ口丸底フラスコに、化合物１３重量８．９ ｍｇ （０．０１３ ｍｍｏｌ）を、クロロホルム３ ｍＬに溶解した溶液を入れ、室温で撹拌しながら酢酸コバルト(II)四水和物９．９ ｍｇ（０．０４０ｍｍｏｌ）を、メタノール３ｍＬに溶解した溶液を加えた。赤から青に変化した。室温で１５分撹拌後、２時間還流した。
反応溶液を冷まし、濃縮し、水で懸濁ろ過をしてろ過物よりコバルト錯体ＭＣ６を得た。

In an argon atmosphere, put a solution of 8.9 mg (0.013 mmol) of compound 13 in 3 mL of chloroform in a 30 mL three-necked round bottom flask, and stir at room temperature to obtain cobalt (II) acetate (4). A solution prepared by dissolving 9.9 mg (0.040 mmol) of hydrate in 3 mL of methanol was added. It changed from red to blue. After stirring at room temperature for 15 minutes, the mixture was refluxed for 2 hours.
The reaction solution was cooled, concentrated, and suspended and filtered with water to obtain a cobalt complex MC6 from the filtrate.

５０ｍＬの２つ口ナス形フラスコに、前記化合物１５ ３３０ｍｇ（０．４７ｍｍｏｌ）を、ジクロロメタン５ｍＬに溶解した溶液に、2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) 108 mg (0.47 mmol)を、ジクロロメタン１０ｍＬに溶解した溶液を、１０分かけて滴下した。その後、室温で１時間撹拌し、反応溶液を得た。
反応溶液にヘキサン３０ｍＬを加え、展開溶媒ヘキサン：クロロホルム＝１：１ (ｖ/ｖ) でシリカゲルカラムクロマトグラフィーを行い、赤色固体の化合物１７を２６７ｍｇ(収率８１％)得た。
¹H NMR (400 MHz, CDCl₃) δ7.92 (d, J = 2.4, 2H), 7.57-7.54 (m, 4H), 7.49-7.44 (m, 3H), 6.93 (d, J = 4.4, 2H), 6.64 (d, J = 4.4, 2H), 3.76 (s, 6H), 1.37 (s, 18H); ¹³C NMR (100 MHz, CDCl₃) δ152.5, 152.2, 149.1, 141.7, 139.7, 137.7, 131.2, 131.0, 129.4, 128.8, 127.7, 127.6, 125.4, 118.6, 118.0, 61.2, 34.8, 31.5. [Synthesis Example 7]
<Synthesis of cobalt complex MC7>

2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) 108 mg (DDQ) in a solution of the above compound 15 330 mg (0.47 mmol) in 5 mL of dichloromethane in a 50 mL two-necked eggplant-shaped flask. 0.47 mmol) was dissolved in 10 mL of dichloromethane, and the solution was added dropwise over 10 minutes. Then, the mixture was stirred at room temperature for 1 hour to obtain a reaction solution.
30 mL of hexane was added to the reaction solution, and silica gel column chromatography was performed with the developing solvent hexane: chloroform = 1: 1 (v / v) to obtain 267 mg (yield 81%) of compound 17 as a red solid.
^{1 1} H NMR (400 MHz, CDCl ₃ ) δ7.92 (d, J = 2.4, 2H), 7.57-7.54 (m, 4H), 7.49-7.44 (m, 3H), 6.93 (d, J = 4.4, 2H) ), 6.64 (d, J = 4.4, 2H), 3.76 (s, 6H), 1.37 (s, 18H); ¹³ C NMR (100 MHz, CDCl ₃ ) δ152.5, 152.2, 149.1, 141.7, 139.7, 137.7 , 131.2, 131.0, 129.4, 128.8, 127.7, 127.6, 125.4, 118.6, 118.0, 61.2, 34.8, 31.5.

アルゴン雰囲気下、３０ｍＬの３つ口丸底フラスコに、化合物１７を３０．０ｍｇ(０．４２８ ｍｍｏｌ)および脱水ジクロロメタン３ｍＬを加え、−２０℃で撹拌しながら三臭化ホウ素のジクロロメタン溶液１．０Ｍを０．８５ｍＬ(０．８５ ｍｍｏｌ)を５分かけて滴下した。３０分後、冷浴を外し４時間撹拌し、反応溶液を得た。さらに、反応溶液を０℃にして、水１ｍＬを滴下した。
反応溶液にクロロホルムを加え、抽出にて飽和炭酸水素ナトリウム水溶液、水、飽和食塩水で洗い、硫酸ナトリウムで乾燥、ろ過、濃縮後、展開溶媒クロロホルムでシリカゲルカラムクロマトグラフィーを行い、赤色個体を１９．３ｍｇ得た。
得られた生成物に対し、３当量の酢酸コバルト４水和物を含んだ３ｍＬのメタノールおよび３ｍＬのクロロホルムの混合溶液を混合し、６０℃に加熱しながら２時間攪拌した。得られた溶液を濃縮乾固させて、残渣へ水を加えて懸濁ろ過して、ろ過物よりＣｏ−Ａ７（コバルト錯体ＭＣ７）を得た。得られたＣｏ−Ａ７のＤＡＲＴ−ＭＳ測定の結果を下記に示す。

Under an argon atmosphere, add 30.0 mg (0.428 mmol) of compound 17 and 3 mL of dehydrated dichloromethane to a 30 mL three-necked round-bottom flask, and add 1.0 M of a dichloromethane solution of boron tribromide while stirring at -20 ° C. 0.85 mL (0.85 mmol) was added dropwise over 5 minutes. After 30 minutes, the cold bath was removed and the mixture was stirred for 4 hours to obtain a reaction solution. Further, the reaction solution was brought to 0 ° C., and 1 mL of water was added dropwise.
Chloroform is added to the reaction solution, washed with saturated aqueous sodium hydrogen carbonate solution, water, and saturated brine for extraction, dried with sodium sulfate, filtered, and concentrated, and then silica gel column chromatography is performed with the developing solvent chloroform. 3 mg was obtained.
A mixed solution of 3 mL of methanol containing 3 equivalents of cobalt acetate tetrahydrate and 3 mL of chloroform was mixed with the obtained product, and the mixture was stirred for 2 hours while heating at 60 ° C. The obtained solution was concentrated to dryness, water was added to the residue, and suspension filtration was performed to obtain Co-A7 (cobalt complex MC7) from the filtrate. The results of DART-MS measurement of the obtained Co-A7 are shown below.

DART-MS (M / Z): found; 729.1. calcd; 729.0 (M + H) ⁺ .

[Example 1]
<Electrode evaluation>
As the electrode, a ring disk electrode having a disk portion of glassy carbon (diameter 6.0 mm) and a ring portion of Pt (ring inner diameter 7.3 mm, ring outer diameter 9.3 mm) was used. Nafion (registered trademark) solution (manufactured by Aldrich, 5) in a sample bottle containing 1 mg of a mixture of cobalt complex MC1 (3% by mass with respect to conductive carbon) and conductive carbon (Ketjen Black EC600JD, Lion). After adding 100 μL of mass% Nafion (registered trademark) solution and 900 μL of ethanol, the sample bottle was irradiated with ultrasonic waves for 15 minutes. 7.2 μL of the obtained dispersion was dropped onto the disk portion of the electrode and air-dried for 1 hour to obtain a measurement electrode.
<Evaluation of oxygen reduction activity>
Using this measuring electrode, the current value of the oxygen reduction reaction was measured under the following measuring device and measuring conditions. The current value is measured in a nitrogen-saturated state (in a nitrogen atmosphere) and in an air-saturated state (in an air atmosphere), and the current value obtained by the measurement in an air atmosphere is used in a nitrogen atmosphere. The value obtained by subtracting the current value obtained in the above measurement was taken as the current value of the oxygen reduction reaction. The current density was determined by dividing this current value by the surface area of the measurement electrode.

(measuring device)
RRDE-1 Rotating Ring Disk Electrode Device ALS Model 701C Dual Electrochemical Analyzer (Measurement Conditions)
Cell solution: 1.0 mol / L sodium chloride, 0.01 mol / L magnesium chloride aqueous solution Solution temperature: 25 ° C
Reference electrode: Silver / silver chloride electrode (saturated potassium chloride)
Counter electrode: Platinum wire Sweep rate: 10 mV / sec Ring potential: 1.125 V vs Silver / silver chloride electrode (saturated potassium chloride)
Electrode rotation speed: 1600 rpm

Using each value of the disk current and the ring current obtained from the measurement, the 4-electron reduction rate of oxygen by the electrode catalyst was determined. The 4-electron reduction rate was calculated based on the following equation.

ここで、ｉ_Dは、ディスク電流密度、ｉ_Rはリング電流密度を表し、Ｎ_r/dはリング電極におけるディスク反応生成物の補足率を表す。補足率は、［Ｆｅ（ＣＮ）₆］^3-/4-の酸化還元系を用いて測定し、実施例に用いた電極においては０．３８であった。
上記捕捉率を用いることにより、前記電極触媒による酸素の４電子還元率を求めた。酸素の４電子還元率を示す。

Here, i _D represents the disk current density, i _R represents the ring current density, and N _{r / d} represents the capture rate of the disk reaction product at the ring electrode. The supplement rate was measured using a redox system of [Fe (CN) ₆ ] ^{3- / 4-} , and was 0.38 for the electrodes used in the examples.
By using the above capture rate, the 4-electron reduction rate of oxygen by the electrode catalyst was determined. It shows the 4-electron reduction rate of oxygen.

[Examples 2 to 4]
As the cobalt complex, instead of the cobalt complex MC1, the cobalt complex MC2 (Example 2), the cobalt complex MC3 (Example 3), the cobalt complex MC4 (Example 4), the cobalt complex MC5 (Example 5), and the cobalt complex MC6 Example 1 using (Example 6), cobalt complex MC7 (Example 7) and iron complex MC8 (Example 8, iron phthalocyanine, manufactured by Aldrich, product code 379549, compound represented by the following formula). The evaluation was performed in the same manner as above.

[Comparative Example 1]
The evaluation was carried out in the same manner as in Example 1 using only carbon without using the cobalt complex.

Since the electrode of the present invention has a high 4-electron reduction rate of oxygen, it can be seen that the generation of hydrogen peroxide is suppressed.

[Reference example 1]
An example of calculating the amount of energy change due to oxygen adsorption will be described using the cobalt complex MC1 as an example. Although it has an acetyl group at the time of metal complex synthesis, it is considered that it is hydrated and desorbed as an acetate anion on the electrode in water, and the structure does not contain an acetyl group. The structure optimization calculation by the density functional theory (B3LYP / LANL2DZ) was performed using the above, and the most stable structure in the triplet state of the monoanion state and its energy value were obtained. After that, the structure optimization calculation was also performed for the structure in which the oxygen molecule was adsorbed in the singlet state of the metal complex, and the structure in which the quintuple state was most stable was obtained. The energy value of the complex before adsorption and the energy value of the oxygen molecule alone were subtracted from the energy value to obtain the amount of energy change.
Regarding the calculation of the amount of energy change in the adsorption of water molecules, the oxygen molecules were replaced with water molecules by the above method. The triplet state of the metal complex on which water molecules were adsorbed was the most stable.
The same method is used for other metal complexes, but for neutral metal complexes that do not have ligands such as halogens and acetyl groups and have coordination unsaturated sites, energy calculations are performed in the monoanion and dianion states. , Each energy change amount was calculated in the most stable state. The results are shown in Table 2. In addition, the oxygen reduction activity was evaluated using the above-mentioned measurement electrodes. The current values of the oxygen reduction reaction are shown in Table 2. The current density is a value at −0.1 V with respect to the silver / silver chloride electrode.

[Reference Example 2] to [Reference Example 4]
As the metal complex, cobalt complex MC5 (Example 2), cobalt complex MC6 (Example 3), iron complex MC8 (Example 4) and cobalt complex MC9 (Example 5) were used instead of the cobalt complex MC1. , The evaluation was performed in the same manner as in Reference Example 1. The cobalt complex MC9 was synthesized according to the following Synthesis Example 8.

[Synthesis Example 8]
<Synthesis of cobalt complex MC9>

Compound 11 was added to J. Am. Chem. Soc. 2011, 133, 10720-10723, followed by synthesis of the cobalt complex MC9 in Chem. Euro. J. It was synthesized by the method described in 2012, 18, 14590-14593. The results of DART-MS measurement of the obtained cobalt complex MC9 are shown below.

DART-MS (M / Z): found; 685.4. calcd; 685.3 (M + H) ⁺ .

[Comparative Reference Example 1] to [Comparative Reference Example 4]
As the metal complex, the cobalt complex RE1 (Comparative Reference Example 1), the cobalt complex RE2 (Comparative Reference Example 2), and the cobalt complex RE3 (Comparative Reference Example 3) are used instead of the cobalt complex MC1 in the same manner as in Reference Example 1. Was evaluated. In addition, as Comparative Reference Example 4, the oxygen reduction activity was evaluated in the same manner as in Reference Example 1 without using a metal complex. As the cobalt complex RE1, a product code 446645 (compound represented by the following structural formula) manufactured by Aldrich was used. The cobalt complex RE2 and the cobalt complex RE3 were synthesized by the following Synthesis Example 9 and Synthesis Example 10, respectively.

窒素雰囲気下において、０．３００ｇの該配位子と０．１４９ｇの酢酸コバルト４水和物を含んだ４ｍｌのエタノールを２５ｍｌのナスフラスコに入れ、８０℃にて１時間攪拌した。生成した褐色沈殿を濾取してエタノールで洗浄後、乾燥することでコバルト錯体ＲＥ２を得た（収量０．１９７ｇ）。 [Synthesis Example 9]
<Synthesis of cobalt complex RE2>
The cobalt complex RE2 was synthesized by mixing and reacting a ligand and ethanol containing cobalt acetate tetrahydrate according to the following reaction formula. The following ligands that are the raw materials of the complex are Tetrahedron. , 1999, 55, 8377.

Under a nitrogen atmosphere, 4 ml of ethanol containing 0.300 g of the ligand and 0.149 g of cobalt acetate tetrahydrate was placed in a 25 ml eggplant flask and stirred at 80 ° C. for 1 hour. The brown precipitate formed was collected by filtration, washed with ethanol, and dried to obtain a cobalt complex RE2 (yield 0.197 g).

まず、窒素雰囲気下において１．９ｇの塩化コバルト６水和物と１．３１gの４―メチル−２，６−ジホルミルフェノールを含んだ５０ｍｌメタノール溶液を１００ｍｌのナスフラスコに入れ、室温にて攪拌した。この溶液に０．５９ｇの１，３−プロパンジアミンを２０ｍｌのメタノールに溶解した溶液を徐々に添加した。上記混合物を３時間還流することにより茶褐色沈殿が生成した。この沈殿を濾取し、乾燥することでコバルト錯体ＲＥ３を得た（収量１．７５ｇ：収率７４％）。 [Synthesis Example 10]
<Synthesis of cobalt complex RE3>
The cobalt complex RE3 was synthesized according to the following reaction formula with reference to the method described in Australian Journal of Chemistry, 23, 2225 (1970).

First, a 50 ml methanol solution containing 1.9 g of cobalt chloride hexahydrate and 1.31 g of 4-methyl-2,6-diformylphenol under a nitrogen atmosphere was placed in a 100 ml eggplant flask and stirred at room temperature. did. A solution prepared by dissolving 0.59 g of 1,3-propanediamine in 20 ml of methanol was gradually added to this solution. The mixture was refluxed for 3 hours to form a brown precipitate. This precipitate was collected by filtration and dried to obtain a cobalt complex RE3 (yield 1.75 g: 74% yield).

The electrode containing the metal complex whose energy change amount due to the adsorption of oxygen molecules by the density general function method (B3LYP / LANL2DZ) is calculated to be -50 to -230 kJ / mol is the current of oxygen reduction. It has a high density, that is, it has a high ability to reduce oxygen, making it an ideal electrode for magnesium air cells.

[Reference Example 6] to [Reference Example 7]
Using the cobalt complex MC7 (Reference Example 6) and the cobalt complex MC10 (Reference Example 7) as the metal complex, the above-mentioned measurement electrodes were prepared and the oxygen reduction activity was evaluated. The current values of the oxygen reduction reaction are shown in Table 3. The current density is a value at −0.1 V with respect to the silver / silver chloride electrode. The cobalt complex MC10 was synthesized according to the following Synthesis Example 11.

＜Ｃｏ−Ａ１の合成＞
Ａ１をＣｈｅｍ． Ｃｏｍｍｕｎ．，２００９，２５４４−２５４６に記載の方法で合成した。
Ａ１の重量１０ｍｇに対し、３当量の酢酸コバルト４水和物を含んだ３ｍＬのメタノールおよび３ｍＬのクロロホルムの混合溶液を混合し、６０℃に加熱しながら２時間攪拌した。得られた溶液を濃縮乾固させて、残渣へ水を加えて懸濁ろ過して、ろ過物よりコバルト錯体ＭＣ１０を得た。 [Synthesis Example 11]

<Synthesis of Co-A1>
A1 is changed to Chem. Commun. , 2009, 2544-2546.
A mixed solution of 3 mL of methanol containing 3 equivalents of cobalt acetate tetrahydrate and 3 mL of chloroform was mixed with respect to a weight of A1 of 10 mg, and the mixture was stirred for 2 hours while heating at 60 ° C. The obtained solution was concentrated to dryness, water was added to the residue, and suspension filtration was performed to obtain a cobalt complex MC10 from the filtrate.

[Comparative Reference Example 5] to [Comparative Reference Example 6]
Instead of the cobalt complex MC7, manganese dioxide (Comparative Reference Example 5) and cobalt phthalocyanine (Comparative Reference Example 6, manufactured by Aldrich, product code 307696) were used in the same manner as in Reference Example 6. The results are shown in Table 3.

Ｃｏフタロシアニン

Co Phthalocyanine

Based on the results of Reference Examples 3 and 5 to 7 and Comparative Reference Examples 4 to 6, the electrode containing the metal complex having the aromatic compound represented by the formula (1) as a ligand has a current density of oxygen reduction. In other words, it has a high ability to reduce oxygen, making it an ideal electrode for magnesium air batteries.

[Example 9]
<Making magnesium-air batteries>
(Preparation of powder for gas diffusion layer)
Carbon black (acetylene black), triton (Kishida chemistry) and water are mixed at a ratio of 1: 1: 30 (weight ratio), and PTFE (Daikin, D-210C) is added to 67% by weight of carbon black. After crushing with a miller for 5 minutes, suction filtration is performed, and the mixture is dried at 120 ° C. for 12 hours. After drying, it is pulverized with a miller and heat-treated in air at 280 ° C. for 3 hours. The powder obtained here is pulverized again with a miller to obtain a powder for a gas diffusion layer.

(Preparation of powder for catalyst layer)
100 ml of water and 1 ml of 1-butanol are placed in a beaker, and 0.18 g of carbon (Ketjen Black 600EC) and 0.08 g of the cobalt metal complex MC1 prepared in Synthesis Example 1 are added thereto. After stirring for 2 hours, 0.16 g of PTFE (Daikin, D-210C) is added little by little, and the mixture is further stirred for 1 hour. It is suction filtered, dried at 120 ° C. and pulverized with a miller to obtain a catalyst layer powder.

(Preparation of positive electrode)
Place aluminum foil on a hot press die, place nickel mesh (manufactured by Nikolai) on it, fill 60 mg of powder for gas diffusion layer electrode, and fill 60 mg of powder for catalyst layer on powder for gas diffusion layer. To do. First, cold pressing is performed at a pressure of 80 kgf / cm ² , and then pressing is performed for 10 seconds using a hot press maintained at 350 ° C. to obtain a positive electrode. The reaction area of the positive electrode is 1.767 cm ² .

(Magnesium air battery)
A magnesium-air battery is assembled using the magnesium plate (manufactured by Elekit, magnesium fuel cell car JS-7900) as the positive electrode and the negative electrode, and copper foil (manufactured by Aldrich, product code 34208) as the current collector of the negative electrode. The power generation of the magnesium-air battery can be confirmed by injecting a 1M sodium chloride aqueous solution as an electrolytic solution, connecting it to a charge / discharge tester (manufactured by Toyo System Co., Ltd., product name: TOSCAT-3000U), and performing a power generation test. ..

The electrode of the present invention can be used as an electrode of a magnesium air battery, and the present invention can provide a magnesium air battery capable of stably generating electricity.

1 ... magnesium-air battery, 11 ... positive electrode catalyst layer, 12 ... positive electrode current collector, 120 ... positive electrode terminal, 13 ... negative electrode active material layer, 14 ... negative electrode current collector, 140 ... negative electrode terminal, 15 ... electrolytic solution

Claims (9)

Used in magnesium-air batteries equipped with an aqueous sodium chloride solution as an electrolytic solution,
Contains one or more metal complexes selected from the group consisting of cobalt complexes and iron complexes
The cobalt complex is a cobalt mononuclear complex and a cobalt polynuclear complex represented by the following formulas.
The iron complex is an electrode for a magnesium-air battery which is an iron mononuclear complex and an iron polynuclear complex represented by the following formula.

(The hydrogen atom in the structural formula may be substituted with another substituent.)

(The hydrogen atom in the structural formula may be substituted with another substituent. A part of cobalt may be substituted with another metal atom or metal ion.)

(The hydrogen atom in the structural formula may be substituted with another substituent.)

(The hydrogen atom in the structural formula may be substituted with another substituent. A part of iron may be substituted with another metal atom or metal ion.) The electrode for a magnesium-air battery according to claim 1, wherein the metal complex is a cobalt complex. The electrode for a magnesium air battery according to claim 2, wherein the cobalt complex has a coordination atom, and at least one of the coordination atoms is a nitrogen atom or an oxygen atom. The electrode for a magnesium air battery according to claim 2 or 3, wherein the cobalt complex has two or more coordination atoms, and the coordination atoms are a nitrogen atom and an oxygen atom. The electrode for a magnesium-air battery according to any one of claims 2 to 4, wherein the cobalt complex is a polynuclear complex. The electrode for a magnesium-air battery according to claim 1, wherein the metal complex is an iron complex. The electrode for a magnesium-air battery according to claim 6, wherein the iron complex has a coordination atom and all of the coordination atoms are nitrogen atoms. The electrode for a magnesium-air battery according to any one of claims 1 to 7, further comprising conductive carbon. A magnesium-air battery comprising the electrode for a magnesium-air battery according to any one of claims 1 to 8 and an electrolytic solution which is an aqueous sodium chloride solution.

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