JP2013040130A - Metal complex, and adsorbing material, occluding material and separating material each comprising the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal complex that exhibits excellent gas-adsorbing performance, excellent gas-occluding performance and excellent gas-separating performance.SOLUTION: The metal complex comprises an aromatic dicarboxylic acid compound represented by general formula (I), represented by 2-methoxyterephthalic acid, at least one metal ion selected from among ions of metals belonging to groups 2 and 7 to 12 of the periodic table, represented by a zinc ion, and a nitrogen-atom-containing aromatic heterocyclic compound bidentately coordinatable to the metal ion, represented by 1,2-bis(4-pyridyl)ethane.

Description

  The present invention relates to a metal complex, and an adsorbent, an occlusion material, and a separation material comprising the same. More specifically, the present invention relates to a metal complex comprising a specific dicarboxylic acid compound, at least one metal ion, and a specific organic ligand capable of bidentate coordination with the metal ion. The metal complex of the present invention is an adsorbent for adsorbing carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbons having 1 to 4 carbon atoms, rare gas, hydrogen sulfide, ammonia, water vapor or organic vapor, It is preferable as an occlusion material for occlusion and a separation material for separation.

  Various occlusion materials have been developed so far in the fields of deodorization and exhaust gas treatment. Activated carbon is a representative example, and is widely used in various industries such as air purification, desulfurization, denitration, and removal of harmful substances by utilizing the excellent occlusion performance of activated carbon. In recent years, the demand for nitrogen is increasing in semiconductor manufacturing processes, etc., and as a method for producing such nitrogen, there is used a method of producing nitrogen from air by pressure swing storage method or temperature swing storage method using molecular sieve charcoal. Has been. Molecular sieve charcoal is also applied to various gas separation and purification such as hydrogen purification from methanol cracked gas.

  When separating mixed gas by pressure swing storage method or temperature swing storage method, in general, molecular sieve charcoal or zeolite is used as the separation storage material, and the separation is performed by the difference in the equilibrium storage amount or storage speed. . However, when the mixed gas is separated based on the difference in the amount of equilibrium occlusion, the conventional occlusion material cannot selectively occlude only the gas to be removed, so the separation factor is reduced, and the size of the apparatus is inevitable. . In addition, when separating the mixed gas based on the difference in adsorption speed, only the gas to be removed can be adsorbed depending on the type of gas, but it is necessary to perform adsorption and desorption alternately, and in this case, the apparatus still has to be large. I didn't get it.

  On the other hand, polymer metal complexes that cause a dynamic structural change due to an external stimulus have been developed as adsorbents that give better adsorption performance. When this new dynamic structure change polymer metal complex is used as a gas adsorbent, a unique phenomenon is observed in which gas adsorption does not adsorb up to a certain pressure, but gas adsorption starts when a certain pressure is exceeded. Yes. In addition, a phenomenon has been observed in which the adsorption start pressure varies depending on the type of gas.

  When this phenomenon is applied to, for example, an adsorbent in a pressure swing adsorption type gas separation apparatus, very efficient gas separation is possible. In addition, the pressure swing width can be narrowed, contributing to energy saving. Furthermore, since it can contribute to miniaturization of the gas separation device, it is possible to increase cost competitiveness when selling high-purity gas as a product, of course, even when high-purity gas is used inside its own factory Since the cost required for the equipment that requires high purity gas can be reduced, the manufacturing cost of the final product can be reduced.

  However, the present situation is that cost reduction by further downsizing of the apparatus is required, and in order to achieve this, further improvement in adsorption performance and storage performance is required.

  A polymer metal complex comprising a terephthalic acid derivative, a metal ion, and an organic ligand capable of bidentate coordination with the metal ion has been disclosed (see Patent Document 1). However, what is described in the examples is a polymer metal complex composed of terephthalic acid, copper ion, and pyrazine, and the substituent of terephthalic acid and the organic ligand capable of bidentate coordination other than pyrazine are gases. No mention is made of the effect on the adsorption behavior.

  A polymer metal complex comprising a terephthalic acid derivative, a metal ion, and an organic ligand capable of bidentate coordination with the metal ion has been disclosed (see Patent Document 2). However, what is described in the examples is a polymer metal complex composed of terephthalic acid, a copper ion, and 1,4-diazabicyclo [2.2.2] octane. -No mention is made of the effect of organic ligands capable of bidentate coordination other than diazabicyclo [2.2.2] octane on gas adsorption behavior.

  A polymer metal complex composed of terephthalic acid, a metal ion, and 4,4'-bipyridyl has been disclosed (see Patent Document 3). However, in the separation of the mixed gas, no mention is made of the effect that the substituents of terephthalic acid and organic ligands capable of bidentate coordination other than 4,4'-bipyridyl have on gas adsorption behavior.

  A hydrocarbon gas adsorbent containing a coordination polymer having a 1,2-bis (4-pyridyl) ethane derivative as an active ingredient has been disclosed (see Patent Document 4). However, what is described in the examples is a porous organometallic complex composed of pyrazine-2,3-dicarboxylic acid, copper ion, and 1,2-bis (4-pyridyl) ethane, and the terephthalic acid derivative is a gas. No mention is made of the effect on the adsorption behavior.

  A gas occlusion characterized by comprising a coordination bond between a metal ion, a dicarboxylic acid compound, and an aromatic heterocyclic compound containing a nitrogen atom capable of coordinating two or more metal ions, and having a pore structure A porous organometallic complex is disclosed (see Patent Document 5). However, what is described in the examples is a porous organometallic complex composed of terephthalic acid, a copper ion, and 1,4-di (4-pyridyl) benzene. No mention is made of the effect of organic ligands other than di (4-pyridyl) benzene capable of bidentate coordination on gas adsorption behavior.

JP 2000-109485 A JP 2001-348361 A JP 2003-342260 A JP 2011-67773 A JP2011-83755A

  Therefore, an object of the present invention is to provide a metal complex that can be used as a gas adsorbent having a larger amount of adsorption than the conventional one, a gas adsorbent having a larger amount of occlusion than the conventional one, or a gas separation material that exhibits higher selectivity than the conventional one. There is to do.

  The present inventors have intensively studied and developed a metal complex comprising a specific dicarboxylic acid compound (I), at least one metal ion, and an organic ligand (II) capable of bidentate coordination with the metal ion. The inventors have found that the above object can be achieved and have reached the present invention.

That is, according to the present invention, the following is provided.
(1) The following general formula (I);

(Wherein R ¹ , R ² , R ³ and R ⁴ 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, nitro A group, a cyano group, a monoalkylamino group, a dialkylamino group, an acylamino group, or a halogen atom, or R ¹ and R ² , or R ³ and R ⁴ may each have a substituent. An alkylene group may be formed, or R ¹ and R ² , R ³ and R ⁴ may be combined together to form an alkadiene group which may have a substituent, provided that R ¹ , R ² , R ³ and R ⁴ are all hydrogen atoms at the same time.) And selected from metal ions belonging to Groups 2 and 7-12 of the Periodic Table At least one metal ion and the following general formula (II):

(Wherein X and Y are the same or different and are CH ₂ , CH (OH), NH, an oxygen atom or a sulfur atom, and R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ and R ¹² 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, a nitro group, a cyano group, an amino group, or a monoalkylamino. A metal complex comprising an organic ligand (II) capable of bidentate coordination to the metal ion represented by: a group, a dialkylamino group, an acylamino group, or a halogen atom.
(2) The metal complex according to (1), wherein the jungle gym skeleton has a structure in which a plurality of interpenetrations occur.
(3) The metal complex according to (1) or (2), wherein the metal ion is a copper ion or a zinc ion.
(4) The metal complex according to any one of (1) to (3), wherein the organic ligand (II) capable of bidentate coordination is 1,2-bis (4-pyridyl) ethane.
(5) An adsorbent comprising the metal complex according to any one of (1) to (4).
(6) The adsorbent is carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbon having 1 to 4 carbon atoms, rare gas, hydrogen sulfide, ammonia, sulfur oxide, nitrogen oxide, siloxane, water vapor or The adsorbent according to (5), which is an adsorbent for adsorbing organic vapor.
(7) An occlusion material comprising the metal complex according to any one of (1) to (4).
(8) The storage material is a storage material for storing carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbon having 1 to 4 carbon atoms, rare gas, hydrogen sulfide, ammonia, water vapor or organic vapor. The occlusion material according to (7).
(9) A separating material comprising the metal complex according to any one of (1) to (4).
(10) The separator is carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbon having 1 to 4 carbon atoms, rare gas, hydrogen sulfide, ammonia, sulfur oxide, nitrogen oxide, siloxane, water vapor or The separation material according to (9), which is a separation material for separating organic vapor.
(11) The separation material is methane and carbon dioxide, ethane and carbon dioxide, ethylene and carbon dioxide, hydrogen and carbon dioxide, nitrogen and carbon dioxide, nitrogen and methane, methane and ethane, ethane and ethylene, ethylene and acetylene, and ethane. The separation material according to (9), which is a separation material for separating propane and propane, propane and propene, methane and ethane and propane, or air and methane.
(12) Dicarboxylic acid compound (I), at least one metal salt selected from salts of metals belonging to Groups 2 and 7-12 of the periodic table, and an organic configuration capable of bidentate coordination with the metal ion The method for producing a metal complex according to (1), wherein the ligand (II) is reacted and precipitated in a solvent.

  According to the present invention, a specific dicarboxylic acid compound (I), at least one metal ion selected from ions of metals belonging to Groups 2 and 7 to 12 of the periodic table, and bidentate coordination to the metal ion are possible. A metal complex comprising the organic ligand (II) can be provided.

  Since the metal complex of the present invention is excellent in the adsorption performance of various gases, carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbons having 1 to 4 carbon atoms, rare gas, hydrogen sulfide, ammonia, sulfur oxidation It can be used as an adsorbent for adsorbing substances, nitrogen oxides, siloxanes, water vapor, organic vapors and the like.

  Moreover, since the metal complex of the present invention is excellent in the occlusion performance of various gases, carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbons having 1 to 4 carbon atoms, rare gas, hydrogen sulfide, ammonia, It can also be used as a storage material for storing water vapor or organic vapor.

  Furthermore, since the metal complex of the present invention is excellent in the separation performance of various gases, carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbons having 1 to 4 carbon atoms, rare gas, hydrogen sulfide, ammonia, It can also be used as a separating material for separating sulfur oxides, nitrogen oxides, siloxanes, water vapor or organic vapors.

It is a schematic diagram of the structural change accompanying adsorption / desorption of the metal complex of this invention. 3 is a powder X-ray diffraction pattern before vacuum drying of the metal complex obtained in Synthesis Example 1. FIG. 3 is a powder X-ray diffraction pattern after vacuum drying of the metal complex obtained in Synthesis Example 1. FIG. 3 is a powder X-ray diffraction pattern before vacuum drying of the metal complex obtained in Comparative Synthesis Example 1. FIG. 3 is a powder X-ray diffraction pattern after vacuum drying of the metal complex obtained in Comparative Synthesis Example 1. FIG. 3 is a powder X-ray diffraction pattern before vacuum drying of the metal complex obtained in Comparative Synthesis Example 2. FIG. 3 is a powder X-ray diffraction pattern after vacuum drying of the metal complex obtained in Comparative Synthesis Example 2. FIG. 3 is a powder X-ray diffraction pattern before vacuum drying of the metal complex obtained in Comparative Synthesis Example 3. FIG. 4 is a powder X-ray diffraction pattern after vacuum drying of the metal complex obtained in Comparative Synthesis Example 3. FIG. It is an adsorption isotherm of ethylene at 195 K of the metal complexes obtained in Synthesis Example 1 and Comparative Synthesis Example 1. 2 is an adsorption isotherm of carbon dioxide at 195 K for the metal complexes obtained in Synthesis Example 1, Comparative Synthesis Example 1 and Comparative Synthesis Example 2. FIG. 2 is an adsorption and desorption isotherm of methane at 195 K of the metal complexes obtained in Synthesis Example 1, Comparative Synthesis Example 2 and Comparative Synthesis Example 3. FIG. 2 is an adsorption / desorption isotherm of methane and nitrogen at 195 K of the metal complex obtained in Synthesis Example 1. FIG. 2 is an adsorption and desorption isotherm of methane and nitrogen at 195 K of the metal complex obtained in Comparative Synthesis Example 2. FIG.

  The metal complex of the present invention comprises a dicarboxylic acid compound (I), at least one metal ion selected from ions of metals belonging to Groups 2 and 7 to 12 of the periodic table, and bidentate coordination to the metal ion. It consists of possible organic ligands (II).

  The metal complex includes a dicarboxylic acid compound (I), at least one metal salt selected from salts of metals belonging to Groups 2 and 7 to 12 of the periodic table, and an organic compound capable of bidentate coordination with the metal ion. Ligand (II) can be produced by reacting it in a solvent under normal pressure for several hours to several days, followed by precipitation. For example, an aqueous solution or an organic solvent solution of a metal salt and an organic solvent solution containing a dicarboxylic acid compound (I) and an organic ligand (II) capable of bidentate coordination are mixed and reacted under normal pressure. Thus, the metal complex of the present invention can be obtained.

  The dicarboxylic acid compound (I) used in the present invention is represented by the following general formula (I):

It is represented by In the formula, R ¹ , R ² , R ³ and R ⁴ 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, a monoalkylamino group, a dialkylamino group, an acylamino group, or a halogen atom, or R ¹ and R ² , or R ³ and R ⁴ may be combined together to have a substituent. A group may be formed, or R ¹ and R ² , R ³ and R ⁴ may be simultaneously combined to form an alkadiene group which may have a substituent. However, when R ¹ , R ² , R ³ and R ⁴ are all simultaneously hydrogen atoms, they are excluded from the above.

Among the substituents that can constitute R ¹ , R ² , R ³ and R ⁴ , 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, examples of alkoxycarbonyl group include methoxycarbonyl group, ethoxycarbonyl group, n-butoxycarbonyl group, examples of monoalkylamino group include methylamino group However, as an example of a dialkylamino group, a dimethylamino group is acyl Examples of amino group, an 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). Etc.), amino group, monoalkylamino group (such as methylamino group), dialkylamino group (such as dimethylamino group), formyl group, epoxy group, acyloxy group (acetoxy group, n-propanoyloxy group, n-butanoyl) Oxy group, pivaloyloxy group, benzoyloxy group, etc.), alkoxycarbonyl group (methoxycarbonyl group, ethoxycarbonyl group, n-butoxycarbonyl group, etc.), carboxylic acid anhydride group (—CO—O—CO—R group) (R Is an alkyl group having 1 to 5 carbon atoms). 1-3 are preferable and, as for the number of the substituents of an alkyl group, one is more preferable.

The alkylene group preferably has 2 carbon atoms. When the alkylene group has 2 carbon atoms, R ¹ and R ² , or R ³ and R ⁴ together with the carbon atom to which they are bonded form a 4-membered ring (cyclobutene ring).

  Examples of the substituent that the alkylene group may have include an alkoxy group (methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, tert-butoxy group, etc.), Amino group, monoalkylamino group (such as methylamino group), dialkylamino group (such as dimethylamino group), formyl group, epoxy group, acyloxy group (acetoxy group, n-propanoyloxy group, n-butanoyloxy group, Pivaloyloxy group, benzoyloxy group, etc.), alkoxycarbonyl group (methoxycarbonyl group, ethoxycarbonyl group, n-butoxycarbonyl group, etc.), carboxylic acid anhydride group (—CO—O—CO—R group) (R is carbon number) 1 to 5 alkyl groups).

  As the dicarboxylic acid compound (I), for example, dihydrocyclobuta [1,2-b] terephthalic acid can be used.

When R ¹ and R ² , R ³ and R ⁴ are alkadiene groups at the same time, it is preferable that both of the alkadiene groups have 4 carbon atoms. When both of the alkadiene groups have 4 carbon atoms, R ¹ and R ² , R ³ and R ⁴ together with the carbon atoms to which they are bonded form a 6-membered ring, constituting an anthracene skeleton To do. In addition, the case where only ^one of R ¹ and R ² or R ³ and R ⁴ forms an alkadiene group (such as naphthalene skeleton) is excluded from the above.

  Examples of the substituent that the alkadiene group may have include an alkoxy group (methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, tert-butoxy group, etc.), Amino group, monoalkylamino group (such as methylamino group), dialkylamino group (such as dimethylamino group), formyl group, epoxy group, acyloxy group (acetoxy group, n-propanoyloxy group, n-butanoyloxy group, Pivaloyloxy group, benzoyloxy group, etc.), alkoxycarbonyl group (methoxycarbonyl group, ethoxycarbonyl group, n-butoxycarbonyl group, etc.), carboxylic acid anhydride group (—CO—O—CO—R group) (R is carbon number) 1 to 5 alkyl groups).

  As the dicarboxylic acid compound (I), for example, 9,10-anthracene dicarboxylic acid can be used.

  Examples of the dicarboxylic acid compound (I) include 2-methylterephthalic acid, 2-methoxyterephthalic acid, 2-nitroterephthalic acid, dihydrocyclobuta [1,2-b] terephthalic acid, 9,10-anthracene dicarboxylic acid, and the like. Among them, 2-methylterephthalic acid, 2-methoxyterephthalic acid and 2-nitroterephthalic acid are preferable, and 2-methoxyterephthalic acid is more preferable.

  Examples of metal ions belonging to groups 2 and 7-12 of the periodic table used in the present invention include magnesium ions, calcium ions, manganese ions, iron ions, cobalt ions, nickel ions, copper ions, zinc ions, and cadmium ions. In particular, copper ions and zinc ions are more preferable. The metal ion is preferably a single metal ion, but may be a mixed metal complex containing two or more metal ions. Moreover, the metal complex of this invention can also mix and use 2 or more types of metal complexes which consist of a single metal ion.

  Examples of salts of metals belonging to Groups 2 and 7-12 of the periodic table used for the production of metal complexes include magnesium salts, calcium salts, manganese salts, iron salts, cobalt salts, nickel salts, copper salts, zinc salts and A cadmium salt or the like can be used, and among them, a copper salt and a zinc salt are preferable. The metal salt is preferably a single metal salt, but two or more metal salts may be mixed and used. As these metal salts, organic acid salts such as acetate and formate, and inorganic acid salts such as hydrochloride, hydrobromide, sulfate, nitrate and carbonate can be used.

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

It is represented by In the formula, X and Y are the same or different and are CH ₂ , CH (OH), NH, an oxygen atom or a sulfur atom, and R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ^11. And R ¹² 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, a nitro group, a cyano group, an amino group, or a monoalkylamino group , A dialkylamino group, an acylamino group or a halogen atom.

  When one or both of X and Y are CH (OH), an asymmetric carbon may be formed, but the bidentate organic ligand (II) is an optical isomer or a mixture thereof, for example, a racemate. May be.

Among the substituents that can constitute R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ and R ¹² , 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, isoproxy 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 groups where the dialkylamino group is dimethylamino group are acyl Examples of amino group, an 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). Etc.), amino group, monoalkylamino group (such as methylamino group), dialkylamino group (such as dimethylamino group), formyl group, epoxy group, acyloxy group (acetoxy group, n-propanoyloxy group, n-butanoyl) Oxy group, pivaloyloxy group, benzoyloxy group, etc.), alkoxycarbonyl group (methoxycarbonyl group, ethoxycarbonyl group, n-butoxycarbonyl group, etc.), carboxylic anhydride group (—CO—OCO—R group) (R is carbon And an alkyl group having a number of 1 to 5). 1-3 are preferable and, as for the number of the substituents of an alkyl group, one is more preferable.

Examples of the bidentate organic ligand (II) include 1,2-bis (4-pyridyl) ethane (X═Y═CH ₂ ), 1,2-bis (4-pyridyl) -glycol. (X = Y = CH (OH)) and 4,4'-dipyridyl sulfide (X = Y = S) can be used, and among these, 1,2-bis (4-pyridyl) ethane is preferred. Here, the organic ligand capable of bidentate coordination means a neutral ligand having at least two sites capable of coordinating to a metal by an unshared electron pair.

  The mixing ratio of the dicarboxylic acid compound (I) to the bidentate organic ligand (II) when producing the metal complex is as follows: dicarboxylic acid compound (I): bidentate organic ligand (II) = 1: 5-8: 1 is preferable, and a molar ratio of 1: 3-6: 1 is more preferable. Even if the reaction is carried out in a range other than this, the desired metal complex can be obtained, but this is not preferable because the yield is lowered and the side reaction is also increased.

  The mixing ratio of the metal salt to the bidentate organic ligand (II) when producing the metal complex is as follows: metal salt: bidentate organic ligand (II) = 3: 1 to 1 : Within the range of the molar ratio of 3: 3, and more preferably within the range of the molar ratio of 2: 1 to 1: 2. In other ranges, the yield of the target metal complex decreases, and purification of the metal complex obtained by leaving unreacted raw materials becomes difficult.

  The molar concentration of the dicarboxylic acid compound (I) in the mixed solution for producing the metal complex is preferably 0.005 to 5.0 mol / L, and more preferably 0.01 to 2.0 mol / L. Even if the reaction is performed at a concentration lower than this, the desired metal complex can be obtained, 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.

  The molar concentration of the metal salt in the mixed solution for producing the metal complex is preferably 0.005 to 5.0 mol / L, and more preferably 0.01 to 2.0 mol / L. Even if the reaction is performed at a concentration lower than this, the desired metal complex can be obtained, but this is not preferable because the yield decreases. Further, at a concentration higher than this, unreacted metal salt remains, and purification of the obtained metal complex becomes difficult.

  The molar concentration of the bidentate organic ligand (II) in the mixed solution for producing the metal complex is preferably 0.001 to 5.0 mol / L, and preferably 0.005 to 2.0 mol / L. More preferred. Even if the reaction is performed at a concentration lower than this, the desired metal complex can be obtained, 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, water or These mixed solvents 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, and then vacuum dried at about 373 K for several hours to obtain the metal complex of the present invention.

  The metal complex of the present invention does not adsorb gas molecules when solvent molecules are adsorbed. Therefore, when using it as an adsorbent, an occlusion material, and a separation material, it is necessary to vacuum-dry the metal complex obtained in advance to remove solvent molecules in the pores.

  The metal complex of the present invention obtained as described above is an organic ligand capable of bidentate coordination to the axial position of the metal ion in the skeleton composed of the carboxylate ion and the metal ion of the dicarboxylic acid compound (I) ( II) has a three-dimensional structure in which the jungle gym skeleton formed by coordination is multiple interpenetrating.

  In this specification, the “jungle gym skeleton” means an organic ligand capable of bidentate coordination at the axial position of the metal ion in the skeleton composed of the carboxylate ion and metal ion of the dicarboxylic acid compound (I). It is defined as a jungle gym-like three-dimensional structure formed by connecting two-dimensional lattice-like sheets composed of dicarboxylic acid compound (I) and metal ions.

  In the present specification, “a structure in which multiple jungle gym skeletons interpenetrate” is defined as a three-dimensional integrated structure in which a plurality of jungle gym skeletons penetrate each other so as to fill the pores.

  The fact that the metal complex has a structure in which the jungle gym skeleton is interpenetrated multiple times can be confirmed by, for example, single crystal X-ray structure analysis, powder X-ray crystal structure analysis, or the like.

  In the metal complex of the present invention, the structure and size of the pores in the jungle gym skeleton are changed by various external stimuli. Examples of the external stimulus include a chemical stimulus such as a substance adsorbed in the pores of the metal complex, or a physical stimulus such as temperature, pressure, and electric field.

  Examples of the substance adsorbed in the pores of the metal complex include carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbons having 1 to 4 carbon atoms, rare gases, ammonia, and other gaseous substances, or water. And liquid substances such as organic compounds that are liquid at normal temperature and pressure.

  Changes in pore structure and size due to external stimuli depend on the type of substance to be adsorbed, the adsorption pressure, and the adsorption temperature. That is, in addition to the difference in the interaction between the pore surface and the substance (the strength of the interaction is proportional to the magnitude of the Lennard-Jones potential of the substance), the degree of structural change varies depending on the adsorbed substance, and thus high selectivity To express. FIG. 1 shows a schematic diagram of the structural change accompanying adsorption / desorption. In the present invention, pore shape and fineness are obtained using the dicarboxylic acid compound (I) represented by the general formula (I) and the organic ligand (II) capable of bidentate coordination represented by the general formula (II). By controlling the charge density on the pore surface, high adsorption performance, high storage performance, and high separation performance are exhibited. After the adsorbed substance is desorbed, it returns to its original structure, so the pore size also returns.

  Although the said adsorption mechanism is presumption, even if it does not follow the said mechanism, if the requirements prescribed | regulated by this invention are satisfied, it will be included in the technical scope of this invention.

  The change in the structure and size of the pores caused by external stimulation of the metal complex can be confirmed by, for example, changes in the powder X-ray diffraction pattern, changes in absorption wavelength, changes in magnetic susceptibility, and the like.

  Since the metal complex of the present invention is excellent in the adsorption performance of various gases, carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbon having 1 to 4 carbon atoms (methane, ethane, ethylene, acetylene, propane, Propene, methylacetylene, propadiene, etc.), noble gases (helium, neon, argon, krypton, xenon, etc.), hydrogen sulfide, ammonia, sulfur oxide, nitrogen oxide, siloxane (hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane) Etc.), and is preferable as an adsorbent for adsorbing water vapor or organic vapor. The organic vapor means a vaporized organic substance that is liquid at normal temperature and pressure. Examples of such organic substances include alcohols such as methanol and ethanol; amines such as trimethylamine; aldehydes such as acetaldehyde; aliphatic hydrocarbons having 5 to 16 carbon atoms; aromatic hydrocarbons such as benzene and toluene; acetone And ketones such as methyl ethyl ketone; halogenated hydrocarbons such as methyl chloride and chloroform.

  In addition, since the metal complex of the present invention is excellent in the occlusion performance of various gases, carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbons having 1 to 4 carbon atoms (methane, ethane, ethylene, acetylene, Propane, propene, methylacetylene, propadiene, etc.), noble gases (helium, neon, argon, krypton, xenon, etc.), hydrogen sulfide, ammonia, water vapor, or organic vapor are preferred as occlusion materials. The organic vapor means a vaporized organic substance that is liquid at normal temperature and pressure. Examples of such organic substances include alcohols such as methanol and ethanol; amines such as trimethylamine; aldehydes such as acetaldehyde; aliphatic hydrocarbons having 5 to 16 carbon atoms; aromatic hydrocarbons such as benzene and toluene; acetone And ketones such as methyl ethyl ketone; halogenated hydrocarbons such as methyl chloride and chloroform.

  Furthermore, since the metal complex of the present invention is excellent in the separation performance of various gases, carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbons having 1 to 4 carbon atoms (methane, ethane, ethylene, acetylene, Propane, propene, methylacetylene, propadiene, etc.), noble gases (helium, neon, argon, krypton, xenon, etc.), hydrogen sulfide, ammonia, sulfur oxide, nitrogen oxide, siloxane (hexamethylcyclotrisiloxane, octamethylcyclohexane) Tetrasiloxane, etc.), and is also preferable as a separating material for separating water vapor or organic vapor, and in particular, carbon dioxide in methane, carbon dioxide in ethane, carbon dioxide in ethylene, carbon dioxide in hydrogen, Carbon dioxide, methane in nitrogen, ethane in methane, ethylene in ethane, in ethylene Acetylene, propane ethane, and methane propene or ethane in methane and propane or air in propane, are suitable for separating the pressure swing adsorption or temperature swing adsorption. The organic vapor means a vaporized organic substance that is liquid at normal temperature and pressure. Examples of such organic substances include alcohols such as methanol and ethanol; amines such as trimethylamine; aldehydes such as acetaldehyde; aliphatic hydrocarbons having 5 to 16 carbon atoms; aromatic hydrocarbons such as benzene and toluene; acetone And ketones such as methyl ethyl ketone; halogenated hydrocarbons such as methyl chloride and chloroform.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited to these. Analysis and evaluation in the following examples and comparative examples were performed as follows.

(1) Measurement of powder X-ray diffraction pattern Using an X-ray diffractometer, the range of diffraction angle (2θ) = 2 to 50 ° was scanned at a scanning speed of 1 ° / min and measured by a symmetric reflection method. Details of the measurement conditions are shown below.
<Analysis conditions>
Apparatus: RINT2400 manufactured by Rigaku Corporation
X-ray source: CuKα (λ = 1.5418Å) 40 kV 200 mA
Goniometer: Vertical goniometer Detector: Scintillation counter Step width: 0.02 °
Slit: Divergent slit = 0.5 °
Receiving slit = 0.15mm
Scattering slit = 0.5 °

(2) Creation of adsorption / desorption isotherm A gas adsorption amount was measured by a capacity method (based on JIS Z8831-2) using a gas adsorption amount measuring device, and an adsorption / desorption isotherm was created. At this time, prior to the measurement, the sample was dried at 373 K and 50 Pa for 10 hours to remove adsorbed water and the like. Details of the measurement conditions are shown below.
<Analysis conditions>
Device: Nippon Bell Co., Ltd. BELSORP-18PLUS
Equilibrium waiting time: 500 seconds

<Synthesis Example 1>
Under a nitrogen atmosphere, zinc nitrate hexahydrate 1.19 g (4.0 mmol), 2-methoxyterephthalic acid 0.79 g (4.0 mmol) and 1,2-bis (4-pyridyl) ethane 0.369 g (2. 0 mmol) was dissolved in 160 mL of N, N-dimethylformamide and stirred at 393 K for 24 hours. As a result of the single crystal X-ray structural analysis of the deposited metal complex, the obtained metal complex had a three-dimensional structure in which the jungle gym skeleton was double interpenetrated. The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it dried at 373 K and 50 Pa for 8 hours, and obtained the target metal complex 0.824g (yield 59%). The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG. From the comparison between FIG. 2 and FIG. 3, the powder X-ray diffraction patterns are different before and after the adsorption and desorption of the synthetic solvent. Therefore, the structure of the present metal complex is dynamically changed with the adsorption and desorption of the synthetic solvent as an external stimulus. I understand that.

<Comparative Synthesis Example 1>
Under a nitrogen atmosphere, zinc nitrate hexahydrate 1.19 g (4.0 mmol), 2-aminoterephthalic acid 0.726 g (4.0 mmol) and 1,2-bis (4-pyridyl) ethane 0.371 g (2. 0 mmol) was dissolved in 160 mL of N, N-dimethylformamide and stirred at 393 K for 24 hours. As a result of the single crystal X-ray structural analysis of the deposited metal complex, the obtained metal complex had a three-dimensional structure in which the jungle gym skeleton was double interpenetrated. The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it dried at 373 K and 50 Pa for 8 hours, and obtained the target metal complex 0.931g (yield 69%). FIG. 7 shows a powder X-ray diffraction pattern of the obtained metal complex. From the comparison between FIG. 4 and FIG. 5, the powder X-ray diffraction patterns are different before and after the adsorption and desorption of the synthetic solvent. Therefore, the structure of this metal complex dynamically changes with the adsorption and desorption of the synthetic solvent as an external stimulus. I understand that.

<Comparative Synthesis Example 2>
In a nitrogen atmosphere, 6.56 g (22 mmol) of zinc nitrate hexahydrate, 3.66 g (22 mmol) of terephthalic acid and 2.03 g (11 mmol) of 1,2-bis (4-pyridyl) ethane were mixed with N, N-dimethylformamide. It was dissolved in 900 mL and stirred at 393 K for 24 hours. As a result of the single crystal X-ray structural analysis of the deposited metal complex, the obtained metal complex had a three-dimensional structure in which the jungle gym skeleton was double interpenetrated. The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it dried at 373 K and 50 Pa for 8 hours, and obtained the target metal complex 5.86g (yield 83%). FIG. 7 shows a powder X-ray diffraction pattern of the obtained metal complex. From the comparison between FIG. 6 and FIG. 7, the powder X-ray diffraction patterns are different before and after the adsorption and desorption of the synthetic solvent. Therefore, the structure of this metal complex dynamically changes with the adsorption and desorption of the synthetic solvent as an external stimulus. I understand that.

<Comparative Synthesis Example 3>
In a nitrogen atmosphere, 2.81 g (9.5 mmol) of zinc nitrate hexahydrate, 1.85 g (9.5 mmol) of 2-methoxyterephthalic acid and 0.739 g (4.7 mmol) of 4,4′-bipyridyl were used. Was dissolved in 800 mL of a mixed solvent of N, N-dimethylformamide and ethanol consisting of N, N-dimethylformamide: ethanol = 1: 1 and stirred at 363 K for 24 hours. As a result of the single crystal X-ray structural analysis of the deposited metal complex, the obtained metal complex had a three-dimensional structure in which the jungle gym skeleton was double interpenetrated. The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it dried at 373K and 50Pa for 8 hours, and obtained the target metal complex 2.28g (yield 71%). The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG. From the comparison between FIG. 8 and FIG. 9, the powder X-ray diffraction pattern is different before and after the adsorption and desorption of the synthetic solvent, so that the structure of this metal complex dynamically changes with the adsorption and desorption of the synthetic solvent which is an external stimulus. I understand that.

<Example 1>
For the metal complex obtained in Synthesis Example 1, the amount of ethylene adsorbed at 195 K was measured by the volumetric method, and an adsorption isotherm was created. The results are shown in FIG.

<Comparative Example 1>
For the metal complex obtained in Comparative Synthesis Example 1, the amount of ethylene adsorbed at 195 K was measured by the volumetric method, and an adsorption isotherm was prepared. The results are shown in FIG.

  FIG. 10 shows that the metal complex of the present invention is excellent as an ethylene adsorbent because it has a large amount of adsorption of ethylene.

<Example 2>
For the metal complex obtained in Synthesis Example 1, the adsorption amount of carbon dioxide at 195 K was measured by a volumetric method, and an adsorption isotherm was created. The results are shown in FIG.

<Comparative example 2>
About the metal complex obtained by the comparative synthesis example 1, the adsorption amount of the carbon dioxide in 195K was measured by the volume method, and the adsorption isotherm was created. The results are shown in FIG.

<Comparative Example 3>
About the metal complex obtained by the comparative synthesis example 2, the adsorption amount of the carbon dioxide in 195K was measured by the capacitance method, and the adsorption isotherm was created. The results are shown in FIG.

  FIG. 11 shows that the metal complex of the present invention is excellent as a carbon dioxide adsorbent because it has a large amount of carbon dioxide adsorbed under low pressure and can adsorb even dilute carbon dioxide.

<Example 3>
For the metal complex obtained in Synthesis Example 1, the adsorption / desorption amount of methane at 195 K was measured by the volumetric method, and an adsorption / desorption isotherm was prepared. The results are shown in FIG.

<Comparative example 4>
For the metal complex obtained in Comparative Synthesis Example 2, the adsorption / desorption amount of methane at 195 K was measured by the volume method, and an adsorption / desorption isotherm was prepared. The results are shown in FIG.

<Comparative Example 5>
For the metal complex obtained in Comparative Synthesis Example 3, the adsorption / desorption amount of methane at 195 K was measured by the volumetric method, and an adsorption / desorption isotherm was prepared. The results are shown in FIG.

  FIG. 12 shows that the metal complex of the present invention is excellent as a methane occlusion material because it has a large effective methane occlusion amount.

<Example 4>
For the metal complex obtained in Synthesis Example 1, the adsorption and desorption amounts of methane and nitrogen at 195 K were measured by the volume method, and adsorption and desorption isotherms were created. The results are shown in FIG.

<Comparative Example 6>
For the metal complex obtained in Comparative Synthesis Example 2, the adsorption and desorption amount of methane and nitrogen at 195 K was measured by the volume method, and an adsorption and desorption isotherm was created. The results are shown in FIG.

  From the comparison between FIG. 13 and FIG. 14, it can be seen that the metal complex of the present invention selectively adsorbs methane and has a large amount of adsorbed methane, and thus is excellent as a separator for nitrogen and methane.

  From the results of Examples 1 to 4 and Comparative Examples 1 to 6, the metal complex obtained in Synthesis Example 1 that satisfies the constitutional requirements of the present invention has a three-dimensional structure in which jungle gym skeletons are interpenetrated multiple times, and externally. The structure is dynamically changed by stimulation, but compared with the metal complexes obtained in Comparative Synthesis Examples 1 to 3 that do not satisfy the constituent requirements of the present invention, it is excellent in adsorption performance, occlusion performance, and separation performance of various gases. it is obvious. The reason why such a difference occurs is not necessarily clear, but by using the constituent ligand of the metal complex of the present invention, the interaction between the gas molecules and the pore surface is increased, so that excellent gas adsorption performance, This is thought to be due to the development of excellent gas storage performance and gas separation performance.

Claims (12)

The following general formula (I);

(Wherein R ¹ , R ² , R ³ and R ⁴ 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, nitro A group, a cyano group, a monoalkylamino group, a dialkylamino group, an acylamino group, or a halogen atom, or R ¹ and R ² , or R ³ and R ⁴ may each have a substituent. An alkylene group may be formed, or R ¹ and R ² , R ³ and R ⁴ may be combined together to form an alkadiene group which may have a substituent, provided that R ¹ , R ² , R ³ and R ⁴ are all hydrogen atoms at the same time.) And selected from metal ions belonging to Groups 2 and 7-12 of the Periodic Table At least one metal ion and the following general formula (II):

(Wherein X and Y are the same or different and are CH ₂ , CH (OH), NH, an oxygen atom or a sulfur atom, and R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ and R ¹² 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, a nitro group, a cyano group, an amino group, or a monoalkylamino. A metal complex comprising an organic ligand (II) capable of bidentate coordination to the metal ion represented by: a group, a dialkylamino group, an acylamino group, or a halogen atom.   The metal complex according to claim 1, wherein the jungle gym skeleton has a structure in which a plurality of interpenetrations occur.   The metal complex according to claim 1 or 2, wherein the metal ion is a copper ion or a zinc ion. The metal complex according to claim 1, wherein the bidentate organic ligand (II) is 1,2-bis (4-pyridyl) ethane. An adsorbent comprising the metal complex according to claim 1. The adsorbent is carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbon having 1 to 4 carbon atoms, rare gas, hydrogen sulfide, ammonia, sulfur oxide, nitrogen oxide, siloxane, water vapor or organic vapor. The adsorbent according to claim 5, which is an adsorbent for adsorbing. The occlusion material which consists of a metal complex in any one of Claims 1-4. The occlusion material is an occlusion material for occluding carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbons having 1 to 4 carbon atoms, rare gas, hydrogen sulfide, ammonia, water vapor or organic vapor. The occlusion material according to 7. The separating material which consists of a metal complex in any one of Claims 1-4.   The separation material is carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbon having 1 to 4 carbon atoms, rare gas, hydrogen sulfide, ammonia, sulfur oxide, nitrogen oxide, siloxane, water vapor or organic vapor. The separation material according to claim 9, which is a separation material for separation.   The separation material is methane and carbon dioxide, ethane and carbon dioxide, ethylene and carbon dioxide, hydrogen and carbon dioxide, nitrogen and carbon dioxide, nitrogen and methane, methane and ethane, ethylene and ethane, ethylene and acetylene, ethane and propane, The separation material according to claim 9, which is a separation material for separating propane, propene, methane, ethane, propane, air, and methane.   A dicarboxylic acid compound (I), at least one metal salt selected from salts of metals belonging to Groups 2 and 7-12 of the periodic table, and an organic ligand capable of bidentate coordination with the metal ion ( The method for producing a metal complex according to claim 1, wherein II) is reacted in a solvent and precipitated.

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