JP2013142082A - Metal complex and anion-removing material comprising the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal complex having a high anion removal activity.SOLUTION: This metal complex includes a copper ion, a carbonate ion and an organic ligand capable of bidentately coordinating with the copper ion and expressed by general formula (I) (wherein, Rto Rare each H, alkyl which may have a substituent, or the like; and Ris substituted methyl having 5-membered or 6-membered heterocyclic ring which may have a substituent containing at least one nitrogen atom), and the composition of the metal complex is expressed by formula (A) [wherein, L is an organic ligand capable of bidentate coordination]. As the organic ligand capable of bidentately coordinating, an imidazolyl group is preferable.

Description

  The present invention relates to a metal complex and an anion-removing material comprising the same. More specifically, the present invention relates to a metal complex comprising a copper ion, a carbonate ion, and a specific organic ligand capable of bidentate coordination with the metal ion. The metal complex of the present invention comprises perchlorate ion, tetrafluoroborate ion, hexafluorophosphate ion, hexafluoroarsenate ion, hexafluoroantimonate ion, methanesulfonate ion, benzenesulfonate ion, trifluoroacetate ion. It is preferable as a removing material for removing trifluoromethanesulfonate ion, nitrate ion, sulfate ion, phosphate ion or halide ion.

  Until now, various harmful anion removing materials have been developed in the field of water treatment. Recently, a special anion exchange resin has been developed as a material having higher removal activity (see, for example, Patent Document 1).

  Examples of harmful anions include solid fuels such as fireworks and rockets, and perchlorate ions used for airbag inflators. Perchlorate ion is a substance that damages the thyroid gland, which controls the metabolic function of adults and promotes physical development in children. As the removal method, there is known a method of concentrating the waste liquid contaminated with perchlorate ions, adding potassium chloride to produce potassium perchlorate, and cooling to crystallize (see Patent Document 2). ).

  Examples of other harmful anions include tetrafluoroborate ions contained in waste liquids such as semiconductor manufacturing processes and plating processes. Boron and fluorine are essential trace elements for animals and plants. However, excessive intake may cause plant growth inhibition, animal reproduction inhibition toxicity, nerve and digestive system disorders, and the like. As the removal method, an aluminum compound, ferric chloride and iron powder are added to and reacted with wastewater containing tetrafluoroborate ions, and the reaction product is neutralized by adding calcium hydroxide, and fluorine is converted into a calcium salt. The method of removing is known (refer patent document 3).

  Moreover, as a removing agent for perchlorate ions and tetrafluoroborate ions, a polymer metal comprising copper sulfate and 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene Complexes are disclosed (see Patent Document 4 and Patent Document 5). When the polymer metal complex contacts with perchlorate ion or tetrafluoroborate ion in solution, it changes its structure into a capsule molecule and can be removed from the solution by capturing these anions. . However, there is a problem that the copper ions in the metal complex elute into the solution when the structure changes, and copper ions are subject to regulation in the wastewater standards related to living environment items by law. There was a need for an anion remover. Further, the removal rate of anions is not satisfactory, and further improvement in performance has been demanded.

JP 2004-346299 A JP-T 9-504472 JP-A-7-16577 WO2008 / 029804 WO2009 / 110499

  Accordingly, an object of the present invention is to provide a metal complex that can be used as a removal material having higher anion removal activity than conventional ones, and has less contamination of the solution after the removal of anions.

  The present inventors have intensively studied and found that the above object can be achieved by a metal complex comprising a copper ion, a carbonate ion, and a specific organic ligand capable of bidentate coordination with the copper ion. It came to.

  That is, according to the present invention, the following is provided.

(1) Copper ion, carbonate ion, and the following general formula (I);

(In the formula, one of R ² , R ³ and R ⁴ is R ^y in the meta position or para position with respect to R ^x , and R ¹ , R ² , R ³ , R ⁴ and R ⁴ except R ^y and R ⁵ is the same or different and each represents a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, a formyl group, an acyloxy group, an alkoxycarbonyl group, a nitro group, a cyano group, an amino group, a monoalkylamino group, A dialkylamino group, an acylamino group, or a halogen atom, wherein R ^x and R ^y are the same or different and have the following general formula:

Wherein R ⁶ and R ⁷ are the same or different and each represents a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, a formyl group, an acyloxy group, an alkoxycarbonyl group, or a nitro group. , A cyano group, an amino group, a monoalkylamino group, a dialkylamino group, an acylamino group, or a halogen atom, and A is a 5- or 6-membered heterocyclic ring optionally having a substituent containing at least one nitrogen atom It is a group. And a metal complex composed of an organic ligand (I) capable of bidentate coordination to the copper ion represented by

  (Wherein L represents an organic ligand (I) capable of bidentate coordination).

(2) The heterocyclic group A possessed by the organic ligand (I) capable of bidentate coordination is a pyrrolyl group excluding a pyrrol-1-yl group, or 2H— excluding a 2H-pyrrol-1-yl group. Indolyl group except pyrrolyl group, imidazolyl group, indol-1-yl group, 3H-indolyl group except 3H-indol-1-yl group, 1H-isoindolyl group except 1H-isoindol-2-yl group , Except benzimidazolyl group, pyrazolyl group, thiazolyl group excluding thiazol-1-yl group, isothiazolyl group excluding isothiazol-1-yl group, and oxazol-1-yl group excluding benzimidazol-3-yl group Oxazolyl group, isoxazolyl group excluding isoxazol-1-yl group, pyrrolidinyl group excluding pyrrolidin-1-yl group, imidazolidini Group, pyrazolidinyl group, pyridyl group excluding pyridin-1-yl group, pyrazin group, pyrimidinyl group, pyridazinyl group, piperidinyl group excluding piperidin-1-yl group, piperazinyl group and morpholin-4-yl group were excluded The metal complex according to (1), which is at least one selected from morpholinyl groups.

(3) An anion removing material comprising the metal complex according to either (1) or (2).

(4) The anion removing material is perchlorate ion, tetrafluoroborate ion, hexafluorophosphate ion, hexafluoroarsenate ion, hexafluoroantimonate ion, methanesulfonate ion, benzenesulfonate ion, trifluoro The anion removing material according to (3), which is a removing material for removing acetate ion, trifluoromethanesulfonate ion, nitrate ion, sulfate ion, phosphate ion or halide ion.

  According to the present invention, a metal complex comprising a copper ion, a carbonate ion, and an organic ligand (I) capable of bidentate coordination with the copper ion can be provided.

  Since the metal complex of the present invention has excellent ability to remove various anions, perchlorate ion, tetrafluoroborate ion, hexafluorophosphate ion, hexafluoroarsenate ion, hexafluoroantimonate ion, methanesulfonate ion , Benzenesulfonate ion, trifluoroacetate ion, trifluoromethanesulfonate ion, nitrate ion, sulfate ion, phosphate ion or halide ion can be used as a removing material.

  Moreover, since the metal complex of this invention can suppress elution of the metal ion in the metal complex accompanying anion removal, it can be used as an anion removal material with little contamination of the solution after anion removal.

3 is a crystal structure of the metal complex obtained in Synthesis Example 1. 3 is a crystal structure of the metal complex obtained in Synthesis Example 2. 3 is a crystal structure of a metal complex obtained in Comparative Synthesis Example 1. It is a crystal structure of the metal complex obtained in Comparative Synthesis Example 2. It is a time-dependent change of the perchlorate ion concentration in Example 1, Example 2, Comparative Example 1, Comparative Example 2, and Comparative Example 3. 4 is a change with time of tetrafluoroborate ion concentration in Example 3, Example 4, Comparative Example 4, Comparative Example 5 and Comparative Example 6. FIG.

The metal complex of the present invention comprises a copper ion (Cu ²⁺ ), a carbonate ion (CO ₃ ²⁻ ), and an organic ligand (I) capable of bidentate coordination with the copper ion.

  The metal complex is formed by reacting copper ions, carbonate ions, and a specific organic ligand (I) capable of bidentate coordination with the copper ions in a solvent at normal pressure for several hours to several days. Can be manufactured. For example, an aqueous solution or organic solvent solution of a copper salt and an aqueous solution or organic solvent solution containing a carbonate ion and an organic ligand capable of bidentate coordination are mixed and reacted under normal pressure to react with the metal of the present invention. A complex can be obtained. At this time, the organic ligand capable of bidentate coordination may be added in a plurality of times.

  The copper salt is preferably a single copper salt, but two or more copper salts may be mixed and used. As these copper salts, organic acid salts such as acetates and formates, and inorganic salts such as carbonates and hydroxide salts can be used.

  The carbonate ion used in the present invention may be added in the form of an alkali metal carbonate or alkaline earth metal carbonate, or may be generated in the system by dissolving carbon dioxide in an alkaline aqueous solution. Further, a counter anion of copper carbonate may be used as it is.

  The organic ligand (I) capable of bidentate coordination used in the present invention has the following general formula (I):

It is represented by In the formula, one of R ² , R ³ and R ⁴ is R ^y in the meta position or para position with respect to R ^x , and R ¹ , R ² , R ³ , R ⁴ and R excluding R ^{y 5} are the same or different and each may be a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, a formyl group, an acyloxy group, an alkoxycarbonyl group, a nitro group, a cyano group, an amino group, a monoalkylamino group, a dialkyl An amino group, an acylamino group, or a halogen atom. R ^x and R ^y are the same or different and have the following general formula:

Wherein R ⁶ and R ⁷ are the same or different and each represents a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, a formyl group, an acyloxy group, an alkoxycarbonyl group, or a nitro group. , A cyano group, an amino group, a monoalkylamino group, a dialkylamino group, an acylamino group, or a halogen atom, and A is a 5- or 6-membered heterocyclic ring optionally having a substituent containing at least one nitrogen atom It is a group.

  The organic ligand capable of bidentate coordination means a neutral ligand having at least two sites coordinated to a metal ion by an unshared electron pair.

Of the substituents that can constitute R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ , the alkyl group or alkoxy group preferably has 1 to 5 carbon atoms. Examples of the alkyl group include a linear or branched alkyl group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, and a pentyl group, and an alkoxy group. Examples of methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, tert-butoxy group, and examples of acyloxy group include acetoxy group, n-propanoyloxy group , N-butanoyloxy group, pivaloyloxy group, benzoyloxy group are examples of alkoxycarbonyl group, methoxycarbonyl group, ethoxycarbonyl group, n-butoxycarbonyl group are examples of monoalkylamino group, methylamino Examples of the dialkylamino group include a dimethylamino group Examples of amino group, acetylamino group, examples of the halogen atom, fluorine atom, chlorine atom, bromine atom, iodine atom, and the like, respectively. Examples of the substituent that the alkyl group may have include an alkoxy group (methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, tert-butoxy group). Dialkylamino group (dimethylamino group, etc.), formyl group, cyano group, epoxy group, acyloxy group (acetoxy group, n-propanoyloxy group, n-butanoyloxy group, pivaloyloxy group, benzoyloxy group, etc.) , Alkoxycarbonyl groups (methoxycarbonyl group, ethoxycarbonyl group, n-butoxycarbonyl group, etc.), carboxylic acid anhydride groups (—CO—O—CO—R group) (R is an alkyl group having 1 to 5 carbon atoms) ) And the like. 1-3 are preferable and, as for the number of the substituents of an alkyl group, one is more preferable.

  In the present invention, the heterocyclic group constituting the above A must have at least one nitrogen atom capable of coordinating with the copper ion in the heterocyclic ring from the viewpoint of the coordination property of the organic ligand (I) to the copper ion. There is. When the heterocyclic group constituting the A has only one nitrogen atom capable of coordinating with a copper ion in the heterocyclic ring, the A is preferably bonded to the benzylic carbon atom at a portion other than the nitrogen atom. . Examples of such A include pyrrolyl group excluding pyrrol-1-yl group, 2H-pyrrolyl group excluding 2H-pyrrol-1-yl group, indolyl group excluding indol-1-yl group, 3H -3H-indolyl group excluding indol-1-yl group, 1H-isoindolyl group excluding 1H-isoindol-2-yl group, benzimidazolyl group excluding benzimidazol-3-yl group, thiazol-1-yl A thiazolyl group excluding a group, an isothiazolyl group excluding an isothiazol-1-yl group, an oxazolyl group excluding an oxazol-1-yl group, an isoxazolyl group excluding an isoxazol-1-yl group, a pyrrolidin-1-yl Pyrrolidinyl group excluding the group, pyridyl group excluding the pyridin-1-yl group, piperidini excluding the piperidin-1-yl group Morpholinyl group, excluding the group or morpholin-4-yl group. Examples of A having two or more nitrogen atoms capable of coordinating to a copper ion in the heterocyclic ring include imidazolyl group, pyrazolyl group, imidazolidinyl group, pyrazolidinyl group, pyrazyl group, pyrimidinyl group, pyridazinyl group or piperazinyl group. Can be mentioned.

The bidentate organic ligand (I) may have one or more asymmetric carbons. The organic ligand (I) capable of bidentate coordination used in the present invention may be any isomer such as an optical isomer, a racemate, an isomer mixture containing many optical isomers, or a diastereoisomer. However, it is preferable that R ⁶ and R ⁷ are the same because they are not asymmetric carbons.

  Preferred compounds of the bidentate organic ligand (I) of the present invention are represented by the following formulas (IA) and (IB):

(Wherein A is as defined above.)

  Examples of the bidentate organic ligand (I) include 1,4-bis (benzimidazol-1-ylmethyl) -2,4,5,6-tetramethylbenzene (I) represented by the following chemical formula: -1), 1,4-bis (4-pyridylmethyl) -2,3,5,6-tetramethylbenzene (I-2), 1,3-bis (imidazol-1-ylmethyl) -2,4 6-trimethylbenzene (I-3), 1,3-bis (4-pyridylmethyl) -2,4,6-trimethylbenzene (I-4), and the like can be used, among which 1,4-bis (Imidazole-1-ylmethyl) -2,3,5,6-tetramethylbenzene (I-1) is more preferred.

  When the metal complex is produced, the mixing ratio of the metal salt and the organic ligand (I) capable of bidentate coordination is preferably in the range of a molar ratio of 1: 5 to 5: 1. A range of 1 molar ratio is more preferred. Even if the reaction is performed in a range other than this, the target metal complex can be obtained, but the yield decreases, and unreacted raw materials remain, making it difficult to purify the obtained metal complex.

  The concentration of the organic ligand (I) capable of bidentate coordination in the solvent for producing the metal complex is preferably 0.01 to 5.0 mol / L, more preferably 0.01 to 2.0 mol / L. . If the concentration is lower than this, the target metal complex can be obtained even if the reaction is carried out, but this is not preferable because the yield decreases. If the concentration is higher than this, the solubility is lowered and the reaction does not proceed smoothly.

  As a solvent used for producing the metal complex, an organic solvent, water, or a mixed solvent thereof can be used. Specifically, methanol, ethanol, propanol, diethyl ether, dimethoxyethane, tetrahydrofuran, hexane, cyclohexane, heptane, benzene, toluene, methylene chloride, chloroform, acetone, ethyl acetate, acetonitrile, N, N-dimethylformamide, dimethyl sulfoxide Aqueous ammonia, water, or a mixed solvent thereof can be used. The reaction temperature is preferably 253 to 423K.

  The completion of the reaction can be confirmed by quantifying the remaining amount of the raw material by gas chromatography or high performance liquid chromatography. After completion of the reaction, the obtained mixed solution is subjected to suction filtration to collect a precipitate, washed with an organic solvent, water or a mixed solvent thereof, and then dried in air or under reduced pressure to dry the metal of the present invention. A complex can be obtained.

  The metal complex of the present invention functions as an anion removing material by changing the structure to an insoluble complex incorporating an anion through an anion exchange reaction when contacting with an anion other than carbonate ion in a solution. For example, when the metal complex of the present invention is immersed in a solution containing perchlorate ions, the metal complex takes in perchlorate ions while changing the structure, and releases carbonate ions into the solution instead. Since the metal complex incorporating the perchlorate ion is insoluble, the perchlorate ion can be removed by performing a treatment such as filtration.

  The metal complex of the present invention is a complex in which three organic ligands (I) capable of bidentate coordination with two copper ions are coordinated, and carbonate ions are necessary to neutralize the charge of the copper ions. There is a great amount. Specifically, it has a composition of copper ion: carbonate ion: bidentate organic ligand (I) = 2: 2: 3. Only when it has this composition, carbonate ions can be chelate coordinated to copper ions, and as a result, coordination bonds between copper ions and organic ligands (I) capable of bidentate coordination by the Yarn-Teller effect. Since the structure is weakened and the structural change to the insoluble metal complex incorporating the anion proceeds easily, high anion removal performance is exhibited.

  In addition, the metal complex of the present invention releases carbonate ions into the system by anion exchange reaction. As a result, the solution becomes alkaline, and the copper ions eluted when the metal complex undergoes structural change precipitates as copper hydroxide. Compared with the case where anions other than carbonate ions are used, the elution amount of copper ions into the solution can be greatly reduced.

  The anion removal mechanism is presumed, but even if it does not follow the mechanism, it is included in the technical scope of the present invention as long as it satisfies the requirements defining the present invention.

  Since the metal complex of the present invention is excellent in the ability to remove various anions, perchlorate ion, tetrafluoroborate ion, hexafluorophosphate ion, hexafluoroarsenate ion, hexafluoroantimonate ion, methanesulfonic acid It is preferable as a removing material for ions, benzenesulfonate ions, trifluoroacetate ions, trifluoromethanesulfonate ions, nitrate ions, sulfate ions, phosphate ions or halide ions.

  The usage form of the anion removing material in the present invention is not particularly limited. For example, the metal complex may be used as powder, pellets, films, sheets, plates, pipes, tubes, rods, granules, various deformed shapes, fibers, hollow fibers, woven fabrics, knitted fabrics, non-woven fabrics, etc. You may shape | mold and use.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. Analysis and evaluation in the following examples and comparative examples were performed as follows.

(1) Single crystal X-ray structure analysis The obtained single crystal was mounted on a gonio head and measured using a single crystal X-ray diffractometer. Details of the analysis conditions are shown below.
<Analysis conditions>
Apparatus: Mercury CCD system manufactured by Rigaku Corporation
X-ray source: MoKα (λ = 0.10773Å) 50 kV 40 mA
Detector: CCD
Collimator: Φ0.50mm
Measurement temperature: 293K
Analysis software: SHELXL97

(2) Determination of anion 200 μL of an anion-containing solution was collected, diluted 25-fold with ultrapure water, and measured using an anion chromatograph.
<Analysis conditions>
Apparatus: 861 Advanced Compact IC manufactured by Metrohm

<Synthesis Example 1>
195 mg (2.0 mmol) of copper hydroxide was dissolved in 30 mL of 28% ammonia water in which carbon dioxide was dissolved, and 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetra was added thereto. 30 mL of ethanol in which 589 mg (2.0 mmol) of methylbenzene was dissolved was added and stirred at 298 K for 12 hours. The produced purple precipitate was collected by suction filtration and washed with 20 mL of water and 20 mL of ethanol. Subsequently, the collected purple precipitate was suspended in 100 mL of methanol, heated and dissolved in 313 K, insoluble matter was removed by filtration, 100 mL of water was added, and the mixture was allowed to stand for 1 day. The precipitated metal complex was collected by suction filtration and then washed with ethanol to obtain 253 mg of metal complex (1). 210 mg (0.50 mmol) of this metal complex (1) was dissolved again in 50 mL of ethanol, and 71.0 mg (0. 0. 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene) was obtained. 25 mmol) was further added, and the mixture was stirred at 313 K for 30 minutes to be dissolved. After cooling to 298K, the insoluble matter was removed by filtration, and the mixture was naturally concentrated for 3 weeks to obtain 220 mg (yield 76%) of the target metal complex as green-blue block crystals. Results of single crystal X-ray structural analysis of the obtained metal complex are shown below. The crystal structure is shown in FIG. From FIG. 1, the composition of the obtained metal complex is copper ion: carbonate ion: 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene = 2: 2: 3. I understand that there is.
Monoclinic (P2 ₁ / n)
a = 12.610 (5) Å
b = 13.430 (5) Å
c = 17.512 (7) Å
β = 105.797 (6) °
V = 2853.7 (19) Å ³
R = 0.0761
Rw = 0.1560

<Synthesis Example 2>
210 mg (0.50 mmol) of the metal complex (1) obtained in Synthesis Example 1 was dissolved again in 50 mL of methanol, and 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene was dissolved. 71.0 mg (0.25 mmol) was further added, and the mixture was stirred at 313 K for 30 minutes to be dissolved. After cooling to 298K, the insoluble matter was removed by filtration, and natural concentration was performed for 2 weeks to obtain 210 mg (yield 66%) of the target metal complex as blue block crystals. Results of single crystal X-ray structural analysis of the obtained metal complex are shown below. The crystal structure is shown in FIG. From FIG. 2, the composition of the obtained metal complex is copper ion: carbonate ion: 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene = 2: 2: 3. I understand that there is.
Monoclinic (C2 / c)
a = 2.895 (10) Å
b = 12.717 (6) Å
c = 24.315 (11) Å
β = 107.182 (4) °
V = 7059 (6) Å ³
R = 0.0794
Rw = 0.0901

<Comparative Synthesis Example 1>
195 mg (2.0 mmol) of copper hydroxide was dissolved in 30 mL of 28% ammonia water in which carbon dioxide was dissolved, and 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetra was added thereto. 30 mL of ethanol in which 589 mg (2.0 mmol) of methylbenzene was dissolved was added and stirred at 298 K for 12 hours. The produced purple precipitate was collected by suction filtration and washed with 20 mL of water and 20 mL of ethanol. Subsequently, the collected purple precipitate was suspended in 100 mL of methanol, heated and dissolved in 313 K, insoluble matter was removed by filtration, 100 mL of water was added, and the mixture was allowed to stand for 1 day. The deposited metal complex was collected by suction filtration and then washed with ethanol to obtain 253 mg (yield 23%) of the metal complex as a purple film crystal. Results of single crystal X-ray structural analysis of the obtained metal complex are shown below. The crystal structure is shown in FIG. From FIG. 3, the composition of the obtained metal complex is copper ion: carbonate ion: 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene = 1: 1: 1. I understand that there is.
Monoclinic (P2 / c)
a = 11.542 (16) Å
b = 5.142 (7) Å
c = 16.88 (3) Å
β = 101.137 (17) °
V = 971 (3) ^{３ 3}
R = 0.0869
Rw = 0.1865

<Comparative Synthesis Example 2>
31.2 mg (0.13 mmol) of copper sulfate pentahydrate was added to 25 mL of water, and 73.6 mg (0.25 mmol) of 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene. ) Was dissolved in 25 mL of N, N-dimethylformamide, and these solutions were mixed and allowed to stand at 298 K for 7 days to obtain 89 mg (yield 85%) of a metal complex as blue plate crystals. Results of single crystal X-ray structural analysis of the obtained metal complex are shown below. The crystal structure is shown in FIG. From FIG. 4, the composition of the obtained metal complex is copper ion: sulfate ion: 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene = 1: 1: 2. I understand that there is.
Monoclinic (C2 / m)
a = 12.3507 (17) Å
b = 27.263 (3) Å
c = 14.377 (3) Å
β = 118.774 °
V = 4243.4 (10) Å3
Z = 2
R = 0.0644
Rw = 0.0722

<Example 1>
75.0 mg of the metal complex obtained in Synthesis Example 1 in 50 mL of 1 mM sodium perchlorate aqueous solution (containing 0.20 mmol of 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene) Was added, and the change with time in the perchlorate ion concentration at 298 K was followed by an anion chromatograph. The results are shown in FIG. At this time, the copper ion concentration in the solution was 0.01 mg / L or less.

<Example 2>
75.0 mg of the metal complex obtained in Synthesis Example 2 in 50 mL of 1 mM sodium perchlorate aqueous solution (containing 0.20 mmol of 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene) Was added, and the change with time in the perchlorate ion concentration at 298 K was followed by an anion chromatograph. The results are shown in FIG. At this time, the copper ion concentration in the solution was 0.01 mg / L or less.

<Comparative Example 1>
50 mL of 1 mM sodium perchlorate aqueous solution contains 0.20 mmol of 83.0 mg (1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene) obtained in Comparative Synthesis Example 1 ) Was added, and the change with time in the perchlorate ion concentration at 298 K was followed by an anion chromatograph. The results are shown in FIG. At this time, the copper ion concentration in the solution was 0.01 mg / L or less.

<Comparative example 2>
170 mg of metal complex obtained in Comparative Synthesis Example 2 (containing 0.20 mmol of 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene) in 50 mL of 1 mM sodium perchlorate aqueous solution In addition, the time course of the perchlorate ion concentration at 298K was followed by anion chromatography. The results are shown in FIG. At this time, the copper ion concentration in the solution was 7.18 mg / L.

<Comparative Example 3>
To 50 mL of a 1 mM aqueous solution of sodium perchlorate, 11.1 mg (0.050 mmol) of basic copper carbonate, 58.9 mg of 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene (0 .20 mmol) was added, and the time course of the perchlorate ion concentration at 298 K was followed by an anion chromatograph. The results are shown in FIG. At this time, the copper ion concentration in the solution was 0.05 mg / L.

  From Example 1 and Example 2, the metal complex of the present invention can quickly remove perchlorate ions, and the amount of copper ions eluted into the solution is small. It turns out that it is excellent.

  On the other hand, when the metal complex of Comparative Synthesis Example 1 whose composition ratio does not satisfy the constituent requirements of the present invention (Comparative Example 1) was used, the elution amount of copper ions was suppressed, but almost all perchlorate ions were removed. I couldn't. When the metal complex of Comparative Synthesis Example 2 using sulfate ions instead of carbonate ions (Comparative Example 2) was used, the removal rate of perchlorate ions was slower than that of the present invention, and a large amount of copper ions Elution was seen. When basic copper carbonate and 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene were added separately (Comparative Example 3), the perchlorate ion removal rate Was slower than the present invention.

<Example 3>
In 50 mL of 1 mM sodium tetrafluoroborate aqueous solution, 75 mg of the metal complex obtained in Synthesis Example 1 (containing 0.20 mmol of 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene) In addition, the time course of the tetrafluoroborate ion concentration at 298K was followed by an anion chromatograph. The results are shown in FIG. At this time, the copper ion concentration in the solution was 0.01 mg / L or less.

<Example 4>
75 mg of the metal complex obtained in Synthesis Example 2 (containing 0.20 mmol of 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene) in 50 mL of 1 mM sodium tetrafluoroborate aqueous solution In addition, the time course of the tetrafluoroborate ion concentration at 298K was followed by an anion chromatograph. The results are shown in FIG. At this time, the copper ion concentration in the solution was 0.01 mg / L or less.

<Comparative example 4>
83 mg of the metal complex obtained in Comparative Synthesis Example 1 in 50 mL of 1 mM sodium tetrafluoroborate aqueous solution (containing 0.20 mmol of 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene) And the change with time of the tetrafluoroborate ion concentration at 298K was followed by an anion chromatograph. The results are shown in FIG. At this time, the copper ion concentration in the solution was 0.01 mg / L or less.

<Comparative Example 5>
170 mg of the metal complex obtained in Comparative Synthesis Example 2 (containing 0.20 mmol of 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene) in 50 mL of 1 mM sodium tetrafluoroborate aqueous solution And the change with time of the tetrafluoroborate ion concentration at 298K was followed by an anion chromatograph. The results are shown in FIG. At this time, the copper ion concentration in the solution was 15.89 mg / L.

<Comparative Example 6>
To 50 mL of a 1 mM sodium tetrafluoroborate aqueous solution, 11.1 mg (0.050 mmol) of basic copper carbonate, 58.9 mg of 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene ( 0.20 mmol) was added, and the change over time in the tetrafluoroborate ion concentration at 298 K was followed by an anion chromatograph. The results are shown in FIG. At this time, the copper ion concentration in the solution was 0.01 mg / L or less.

  From Example 3 and Example 4, the metal complex of the present invention can quickly remove tetrafluoroborate ions and the amount of copper ions eluted into the solution is small. It turns out that it is excellent as a material.

  On the other hand, when the metal complex of Comparative Synthesis Example 1 whose composition ratio does not satisfy the constituent requirements of the present invention (Comparative Example 4) was used, the elution amount of copper ions was suppressed, but almost all tetrafluoroborate ions were removed. I couldn't. In the case of using the metal complex of Comparative Synthesis Example 2 using sulfate ions instead of carbonate ions (Comparative Example 5), the removal rate of tetrafluoroborate ions is slower than that of the present invention, and a large amount of copper ions Elution was observed. When basic copper carbonate and 1,4-bis (imidazol-1-ylmethyl) -2,3,5,6-tetramethylbenzene were added separately (Comparative Example 6), removal of tetrafluoroborate ions The speed was slow compared to the present invention.

Claims (4)

Copper ions, carbonate ions, and the following general formula (I):

(In the formula, one of R ² , R ³ and R ⁴ is R ^y in the meta position or para position with respect to R ^x , and R ¹ , R ² , R ³ , R ⁴ and R ⁴ except R ^y and R ⁵ is the same or different and each represents a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, a formyl group, an acyloxy group, an alkoxycarbonyl group, a nitro group, a cyano group, an amino group, a monoalkylamino group, A dialkylamino group, an acylamino group, or a halogen atom, wherein R ^x and R ^y are the same or different and have the following general formula:

Wherein R ⁶ and R ⁷ are the same or different and each represents a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, a formyl group, an acyloxy group, an alkoxycarbonyl group, or a nitro group. , A cyano group, an amino group, a monoalkylamino group, a dialkylamino group, an acylamino group, or a halogen atom, and A is a 5- or 6-membered heterocyclic ring optionally having a substituent containing at least one nitrogen atom It is a group. And a metal complex composed of an organic ligand capable of bidentate coordination with the copper ion represented by
(Wherein L represents an organic ligand capable of bidentate coordination).   The heterocyclic group A of the organic ligand (I) capable of bidentate coordination is a pyrrolyl group excluding a pyrrol-1-yl group, a 2H-pyrrolyl group excluding a 2H-pyrrol-1-yl group, Indolyl group excluding imidazolyl group, indol-1-yl group, 3H-indolyl group excluding 3H-indol-1-yl group, 1H-isoindolyl group excluding 1H-isoindol-2-yl group, benzimidazole Benzimidazolyl group excluding -3-yl group, pyrazolyl group, thiazolyl group excluding thiazol-1-yl group, isothiazolyl group excluding isothiazol-1-yl group, oxazolyl group excluding oxazol-1-yl group , Isoxazolyl group excluding isoxazol-1-yl group, pyrrolidinyl group excluding pyrrolidin-1-yl group, imidazolidinyl group, Razolidinyl group, pyridyl group excluding pyridin-1-yl group, pyrazin group, pyrimidinyl group, pyridazinyl group, piperidinyl group excluding piperidin-1-yl group, morpholinyl group excluding piperidinyl group and morpholin-4-yl group The metal complex according to claim 1, which is at least one selected from the group consisting of:   An anion removing material comprising the metal complex according to claim 1.   The anion removing material is perchlorate ion, tetrafluoroborate ion, hexafluorophosphate ion, hexafluoroarsenate ion, hexafluoroantimonate ion, methanesulfonate ion, benzenesulfonate ion, trifluoroacetate ion, The anion removing material according to claim 3, which is a removing material for removing trifluoromethanesulfonate ion, nitrate ion, sulfate ion, phosphate ion or halide ion.