JP2011195575A - Metal complex and production method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal complex which has outstanding gas occlusion performance and outstanding gas separation performance.

SOLUTION: The metal complex includes: an aromatic dicarboxylic acid compound (I) in which carboxyl groups are in mutual most distant positions within a constitutional formula, which has ten or more π electrons which annularly conjugate, and in which the number of carbon atoms which compose an aromatic ring is 10-18; at least one sort of a metal ion chosen from an ion of a metal belonging to group 2 and groups 7-12 of the periodic table; and an organic ligand in which the point group is D_∞h, and the length in the direction of a major axis is 8.0 Å or more and less than 16.0 Å, and which can bidentately coordinate to the metal ion having 2-5 hetero atoms. The subject problem is solved by the metal complex.

COPYRIGHT: (C)2012,JPO&INPIT

Description

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

  So far, various adsorbents have been developed in fields such as 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 adsorption performance of activated carbon. In recent years, the demand for nitrogen has increased for semiconductor manufacturing processes, etc., and as a method for producing such nitrogen, a method of producing nitrogen from air by pressure swing adsorption method or temperature swing adsorption method using molecular sieve charcoal is used. 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 adsorption method or temperature swing adsorption method, generally, molecular sieve charcoal or zeolite is used as the separation adsorbent, and separation is performed by the difference in the equilibrium adsorption amount or adsorption rate. . However, when separating the mixed gas based on the difference in the amount of equilibrium adsorption, the conventional adsorbents cannot selectively adsorb only the gas to be removed, so the separation factor becomes small, 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 by an external stimulus have been developed as adsorbents that give better adsorption performance (see Non-Patent Document 1 and Non-Patent Document 2). 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 current situation is that cost reduction by further downsizing of the apparatus is required, and further improvement in separation performance is required to achieve this.

  A polymer metal complex composed of an aromatic dicarboxylic acid derivative, a metal ion, and an organic ligand capable of bidentate coordination with the metal ion is disclosed (see Patent Document 1). However, what is described in the examples is a polymer metal complex composed of terephthalic acid, copper ions, and pyrazine, and no mention is made of the effect of the dicarboxylic acid compound on gas storage performance and mixed gas separation performance.

  A polymer metal complex composed of an aromatic dicarboxylic acid derivative, a metal ion, and an organic ligand capable of bidentate coordination with the metal ion is disclosed (see Patent Document 2). However, what is described in the examples is a polymer metal complex composed of 4,4′-biphenyldicarboxylic acid, a copper ion, and 1,4-diazabicyclo [2.2.2] octane. No mention is made of the effect of possible organic ligands on gas storage performance and mixed gas separation performance.

  Terephthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-biphenyldicarboxylic acid, 2,7-pyrenedicarboxylic acid or 4,5,9,10-tetrahydropyrene-2,7-dicarboxylic acid, metal ion, and A polymer metal complex comprising an organic ligand capable of bidentate coordination to a metal ion has been disclosed (see Patent Document 3). However, what is described in the examples is a polymer metal complex composed of terephthalic acid, copper ion and 1,4-diazabicyclo [2.2.2] octane, 2,6-naphthalenedicarboxylic acid, copper ion and 1 , 4-diazabicyclo [2.2.2] octane and polymer metal complex consisting of terephthalic acid, rhodium ion and 1,4-diazabicyclo [2.2.2] octane, mixed No mention is made of gas separation performance.

  2,6-naphthalenedicarboxylic acid, 4,4′-biphenyldicarboxylic acid, 2,7-pyrene dicarboxylic acid or 4,5,9,10-tetrahydropyrene-2,7-dicarboxylic acid, metal ion, and metal ion A polymer metal complex comprising an organic ligand capable of bidentate coordination has been disclosed (see Patent Document 4). However, the examples describe polymer metal complexes composed of 2,6-naphthalenedicarboxylic acid, copper ions and 1,4-diazabicyclo [2.2.2] octane and 4,4′-biphenyldicarboxylic acid. Polymer metal complex consisting of acid, copper ion and 1,4-diazabicyclo [2.2.2] octane, and the effect of organic ligands capable of bidentate coordination on gas storage performance and mixed gas separation performance There is no mention about.

JP 2000-109485 A JP 2001-348361 A JP 2006-328051 A JP 2008-208110 A

Kazuhiro Uemura, Susumu Kitagawa, Future Materials, Volume 2, 44-51 (2002) Ryotaro Matsuda, Susumu Kitagawa, Petrotech, Vol. 26, 97-104 (2003)

  Therefore, the objective of this invention is providing the metal complex which can be used as a gas storage material with a larger effective occlusion amount than before, and a gas separation material which is more excellent in the separation performance of mixed gas than before.

  The present inventors have intensively studied and achieve the above object with a metal complex comprising a specific dicarboxylic acid compound, at least one metal ion, and an organic ligand capable of bidentate coordination with the metal ion. The present inventors have found that it is possible to achieve the present invention.

That is, according to the present invention, the following is provided.
(1) An aromatic group in which the carboxyl group is located farthest from each other in the structural formula, has 10 or more π electrons conjugated in a cyclic manner, and has 10 to 18 carbon atoms constituting the aromatic ring A dicarboxylic acid compound, at least one metal ion selected from ions of metals belonging to Groups 2 and 7-12 of the periodic table, a point group of _D∞h , and a length in the major axis direction of 8 A metal complex comprising an organic ligand which is bidentate to the metal ion having a molecular weight of 0.0 to 16.0 and having 2 to 5 heteroatoms.
(2) The aromatic dicarboxylic acid compound is represented by the following general formula (I);

(Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are the same or different and each is a hydrogen atom, an alkyl group optionally having 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). The metal complex described.
(3) The aromatic dicarboxylic acid compound is represented by the following general formula (II);

(Wherein R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are the same or different and each represents a hydrogen atom, an alkyl group which may have a substituent, or an alkoxy group. , Formyl group, acyloxy group, alkoxycarbonyl group, nitro group, cyano group, amino group, monoalkylamino group, dialkylamino group, acylamino group or halogen atom, R ⁸ and R ⁹ , or R ¹² and R ¹³ And a dicarboxylic acid compound (II) represented by (1) which may form an alkylene group or alkenylene group which may have a substituent.
(4) The bidentate organic ligand is 1,2-bis (4-pyridyl) ethyne, 1,4-bis (4-pyridyl) benzene and 4,4′-bis (4-pyridyl). The metal complex according to (1), which is at least one selected from biphenyl.
(5) The metal complex according to any one of (1) to (4), wherein the metal ion is a zinc ion.
(6) An occlusion material comprising the metal complex according to any one of (1) to (5).
(7) The storage material is a storage material for storing 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 storage material according to (6).
(8) A separating material comprising the metal complex according to any one of (1) to (5).
(9) 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 (8), which is a separation material for separating organic vapor.
(10) The separation material according to (8), wherein the separation material is a separation material for separating methane and carbon dioxide, hydrogen and carbon dioxide, nitrogen and carbon dioxide, methane and ethane, or air and methane.
(11) An aromatic group in which the carboxyl group is located farthest from each other in the structural formula, has 10 or more π electrons conjugated in a cyclic manner, and has 10 to 18 carbon atoms constituting the aromatic ring A dicarboxylic acid compound, at least one metal salt selected from salts of metals belonging to Groups 2 and 7-12 of the periodic table, a point group of _D∞h , and a length in the major axis direction of 8 An organic ligand capable of bidentate coordination with the metal ion having 2 to 5 heteroatoms and not less than 0.01 and less than 16.0 cm, in a solvent, to precipitate a metal complex, (1) A method for producing the metal complex described in 1.

According to the present invention, there is an aromatic in which the carboxyl group is located farthest from each other in the structural formula, has 10 or more π electrons conjugated in a cyclic manner, and has 10 to 18 carbon atoms constituting the aromatic ring. Group dicarboxylic acid compound, at least one metal, the point group is _D∞h , the length in the major axis direction is from 8.0 to less than 16.0 and has 2 to 5 heteroatoms A metal complex comprising an organic ligand capable of bidentate coordination with the metal ion can be provided.

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

  Moreover, since the metal complex of the present invention has different adsorption start pressures depending on the gas type, carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, hydrocarbons having 1 to 4 carbon atoms, rare gas, hydrogen sulfide, ammonia, sulfur Can also be used as a separator for separating oxides, nitrogen oxides, siloxanes, water vapor or organic vapors, especially methane and carbon dioxide, hydrogen and carbon dioxide, nitrogen and carbon dioxide, methane and ethane or air It can be used as a separating material such as carbon dioxide.

Jungle Jim formed by coordination of bidentate organic ligand (II) at the axial position of the metal ion in the paddle wheel skeleton consisting of the carboxylate ion and metal ion of the dicarboxylic acid compound (I) It is a schematic diagram of a skeleton. It is a schematic diagram of a three-dimensional structure when a jungle gym skeleton double interpenetrates. It is a schematic diagram of the structural change accompanying adsorption / desorption of the metal complex of this invention. 3 is a crystal structure of the metal complex obtained in Synthesis Example 1. 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 after vacuum drying of the metal complex obtained in Synthesis Example 2. FIG. 3 is a powder X-ray diffraction pattern after vacuum drying of the metal complex obtained in Synthesis Example 3. 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 after vacuum drying of the metal complex obtained in Comparative Synthesis Example 2. FIG. 4 is a powder X-ray diffraction pattern after vacuum drying of the metal complex obtained in Comparative Synthesis Example 3. FIG. 7 is a powder X-ray diffraction pattern after vacuum drying of the metal complex obtained in Comparative Synthesis Example 4. FIG. 7 is a powder X-ray diffraction pattern after vacuum drying of the metal complex obtained in Comparative Synthesis Example 5. FIG. 7 is a powder X-ray diffraction pattern after vacuum drying of the metal complex obtained in Comparative Synthesis Example 6. FIG. 7 is a powder X-ray diffraction pattern after vacuum drying of the metal complex obtained in Comparative Synthesis Example 7. FIG. It is the result of having measured the adsorption-desorption isotherm in 273K of a carbon dioxide by the capacitance method about the metal complex obtained by the synthesis example 1. FIG. It is the result of having measured the adsorption-desorption isotherm of carbon dioxide at 273K by the volume method for the metal complex obtained in Comparative Synthesis Example 1. It is the result of having measured the adsorption-desorption isotherm in 273K of a carbon dioxide by the capacitance method about the metal complex obtained by the comparative synthesis example 3. FIG. It is the result of measuring the adsorption / desorption isotherm of carbon dioxide at 273 K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 4. It is the result of measuring the adsorption / desorption isotherm of carbon dioxide at 273 K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 6. It is the result of having measured the adsorption-desorption isotherm in 273K of ethane by the capacitance method about the metal complex obtained in the synthesis example 1. FIG. It is the result of having measured the adsorption / desorption isotherm in 273K of ethane by the capacitance method about the metal complex obtained by the comparative synthesis example 1. FIG. It is the result of having measured the adsorption / desorption isotherm in 273K of ethane by the capacitance method about the metal complex obtained by the comparative synthesis example 4. FIG. It is the result of having measured the adsorption-desorption isotherm in ethylene at 273K by the capacitance method about the metal complex obtained by the synthesis example 1. FIG. It is the result of having measured the adsorption-desorption isotherm in ethylene at 273K by the volume method about the metal complex obtained by the comparative synthesis example 1. FIG. It is the result of having measured the adsorption-desorption isotherm in ethylene at 273K by the capacitance method about the metal complex obtained by the comparative synthesis example 4. FIG. It is the result of having measured the adsorption-desorption isotherm in 273K of a carbon dioxide by the capacitance method about the metal complex obtained by the synthesis example 2. FIG. It is the result of having measured the adsorption-desorption isotherm at 273K of a carbon dioxide by the capacitance method about the metal complex obtained by the comparative synthesis example 2. FIG. It is the result of having measured the adsorption-desorption isotherm in 273K of a carbon dioxide by the capacitance method about the metal complex obtained by the comparative synthesis example 5. FIG. It is the result of having measured the adsorption-desorption isotherm in 195K of a carbon dioxide by the capacitance method about the metal complex obtained by the synthesis example 3. FIG. It is the result of measuring the adsorption / desorption isotherm of carbon dioxide at 195 K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 7. It is the result of having measured the adsorption-desorption isotherm of ethane and methane in 273K by the capacitance method about the metal complex obtained by the synthesis example 1. FIG. It is the result of having measured the adsorption / desorption isotherm in 273K of ethane and methane by the capacitance method about the metal complex obtained by the comparative synthesis example 1. FIG. It is the result of having measured the adsorption / desorption isotherm in 273K of ethane and methane by the capacitance method about the metal complex obtained by the comparative synthesis example 4. FIG. It is the result of measuring the adsorption-desorption isotherm of carbon dioxide and nitrogen at 273 K by the capacitance method for the metal complex obtained in Synthesis Example 1. It is the result of measuring the adsorption-desorption isotherm of carbon dioxide and nitrogen at 273 K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 1.・ It is the result of having measured the adsorption-desorption isotherm of carbon dioxide and nitrogen at 273K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 4. It is the result of having measured the adsorption-desorption isotherm of carbon dioxide and nitrogen at 273K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 6. It is the result of measuring the adsorption-desorption isotherm of carbon dioxide and nitrogen at 273 K by the volumetric method for the metal complex obtained in Synthesis Example 2. It is the result of having measured the adsorption-desorption isotherm in carbon dioxide and nitrogen at 273K by the capacitance method about the metal complex obtained by the comparative synthesis example 2. FIG.

The metal complex of the present invention has 10 or more π electrons having a carboxyl group at the furthest position in the structural formula and cyclically conjugated, and 10 to 18 carbon atoms constituting an aromatic ring. An aromatic dicarboxylic acid compound, at least one metal ion selected from ions of metals belonging to Groups 2 and 7-12 of the periodic table, a point group of _D∞h , and a long axis direction It consists of an organic ligand having a length of from 8.0 to less than 16.0 and capable of bidentate coordination with the metal ion having 2 to 5 heteroatoms.

The metal complex of the present invention has 10 or more π electrons having a carboxyl group at the furthest position in the structural formula and cyclically conjugated, and 10 to 18 carbon atoms constituting an aromatic ring. An aromatic dicarboxylic acid compound, at least one metal salt selected from the salts of metals belonging to Groups 2 and 7-12 of the periodic table, a point group of _D∞h , and a long axis direction An organic ligand having a length of 8.0 to less than 16.0 and capable of bidentate coordination with the metal ion having 2 to 5 heteroatoms in a solvent under normal pressure to several hours It can be produced by reacting for a day and precipitating. For example, the metal complex of the present invention can be prepared by mixing and reacting an aqueous solution or organic solvent solution of a metal salt with an organic solvent solution containing a dicarboxylic acid compound and an organic ligand capable of bidentate coordination under normal pressure. Can be obtained.

The aromatic hydrocarbon ring portion obtained by removing two carboxyl groups and R ^{1 to} R ¹⁴ from the compound of the aromatic dicarboxylic acid compound is preferably polycyclic. Examples of the polycyclic aromatic hydrocarbon ring include naphthalene, azulene, phenanthrene, anthracene, triphenylene, chrysene, naphthacene, picene, pentaphen, pentacene, biphenyl and the like. Of these, naphthalene or biphenyl is preferred. “In the structural formula, the carboxyl groups are farthest from each other” means that the linear distance between the carbon atoms to which the two carboxyl groups are bonded is the longest, for example, naphthalene. In the case of, it means that the positions are 2-position and 6-position or 3-position and 7-position, and in the case of biphenyl, it means that the positions are 4-position and 4'-position.

The number of π electrons conjugated to the ring of the aromatic dicarboxylic acid compound is the number of conjugated π electrons existing in the two carboxyl groups of the aromatic dicarboxylic acid compound and the aromatic hydrocarbon ring other than R ^{1 to} R ^14. 10 to 18 is preferable. When an aromatic dicarboxylic acid compound having a π electron number of less than 10 is used, the amount of occlusion and separation performance decreases, and when an aromatic dicarboxylic acid compound having a π electron number of more than 18 is used, the stability of the resulting metal complex , Crystallinity and yield may decrease.

  Examples of the aromatic dicarboxylic acid compound include the following general formulas (I) and (II);

The compound represented by these is preferable. In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are the same or different. Hydrogen atom, optionally substituted alkyl group, alkoxy group, formyl group, acyloxy group, alkoxycarbonyl group, nitro group, cyano group, amino group, monoalkylamino group, dialkylamino group, acylamino group or halogen It may be an atom, or R ⁸ and R ⁹ , and / or R ¹² and R ¹³ may be combined to form an alkylene or alkenylene group which may have a substituent.

Substitutions that can constitute R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ . Among the groups, 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). 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.

  Examples of the dicarboxylic acid compound (I) include 2,6-naphthalenedicarboxylic acid.

The alkylene group preferably has 2 carbon atoms. When the alkylene group has 2 carbon atoms, R ⁸ and R ⁹ and / or R ¹² and R ¹³ together with the carbon atom to which they are bonded form a 6-membered ring (cyclohexadiene ring). Examples of such dicarboxylic acid compound (II) include 4,5,9,10-tetrahydropyrene-2,7-dicarboxylic acid which may have a substituent.

The alkenylene group preferably has 2 carbon atoms. When the alkenylene group has 2 carbon atoms, R ⁸ and R ⁹ and / or R ¹² and R ¹³ together with the carbon atom to which they are bonded form a 6-membered ring (benzene ring). Examples of such dicarboxylic acid compound (II) include 2,7-pyrene dicarboxylic acid which may have a substituent.

  Examples of the substituent that the alkylene group or the alkenylene 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 (methylamino group etc.), dialkylamino group (dimethylamino group etc.), 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 anhydride group (-CO-O-CO-R group) (R is an alkyl group having 1 to 5 carbon atoms).

  As the dicarboxylic acid compound (II), 4,4′-biphenyldicarboxylic acid, 2,7-pyrene dicarboxylic acid or 4,5,9,10-tetrahydropyrene-2,7-dicarboxylic acid can be used. Of these, 4,4′-biphenyldicarboxylic acid is preferred.

  Magnesium, calcium, manganese, iron, ruthenium, cobalt, rhodium, nickel, palladium, copper, zinc, or cadmium salts are used as metal salts for the production of metal complexes. A magnesium salt, a manganese salt, a cobalt salt, a nickel salt, a copper salt, a zinc salt or a cadmium salt is preferable, and a zinc salt is more preferable. The metal salt is preferably a single metal salt, but two or more metal salts may be mixed and used. 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. Further, as these metal salts, organic acid salts such as acetates and formates, inorganic acid salts such as sulfates, nitrates, carbonates, hydrochlorides and hydrobromides can be used.

The organic ligand capable of bidentate coordination used in the present invention has a point group of _D∞h , a length in the major axis direction of from 8.0 to less than 16.0, and a hetero atom of 2 to Have five. Here, the bidentate organic ligand means a neutral ligand having two or more atoms coordinated to a metal ion by a lone pair.

The point group of the organic ligand capable of bidentate coordination can be determined according to the method described in Reference Document 1 below.
Reference 1: Masao Nakazaki, Molecular symmetry and group theory, 39-40 (1973, Tokyo Chemical Doujin)

For example, 1,2-bis (4-pyridyl) ethyne, 1,4-bis (4-pyridyl) benzene and 4,4′-bis (4-pyridyl) biphenyl are symmetric linear molecules and have a symmetrical center. Therefore, the point cloud is D _∞h . In addition, 1,2-bis (4-pyridyl) ethene has a two-fold rotation axis and a plane of symmetry perpendicular to the axis, so the point group is C _2h .

When the point group of the organic ligand capable of bidentate coordination is other than D _∞h , useless voids are generated due to low symmetry, and the amount of adsorption decreases.

  The length in the major axis direction of the organic ligand capable of bidentate coordination in this specification was determined using conformational analysis by molecular dynamics method MM3 using Scigress Explorer Professional Version 7.6.0.52 manufactured by Fujitsu Limited. After that, in the most stable structure obtained by optimizing the structure with the semi-empirical molecular orbital method PM5, the center of the two atoms located farthest in the structural formula among the atoms coordinated to the metal ion It is defined as the distance between.

  For example, the distance between nitrogen atoms of 1,4-diazabicyclo [2.2.2] octane is 2.609Å, the distance between nitrogen atoms of pyrazine is 2.810Å, and the distance between nitrogen atoms of 4,4′-bipyridyl is 7. The distance between nitrogen atoms of 061Å, 1,2-bis (4-pyridyl) ethyne is 9.583Å, and the distance between nitrogen atoms of 1,4-bis (4-pyridyl) benzene is 11.315Å, 3,6-di ( The distance between nitrogen atoms of 4-pyridyl) -1,2,4,5-tetrazine is 11.204 mm, and the distance between nitrogen atoms of 4,4′-bis (4-pyridyl) biphenylene is 15.570 mm, N, N ′ The distance between nitrogen atoms of -di (4-pyridyl) -1,4,5,8-naphthalenetetracarboxydiimide is 15.533Å.

  When the length in the major axis direction of the organic ligand capable of bidentate coordination is less than 8.0 mm, the pore diameter becomes too small and the interaction between the gas molecule and the pore wall becomes large. descend. On the other hand, when the length in the major axis direction is 16.0 mm or more, the pore diameter becomes too large, and the interaction between the gas molecules and the pore walls becomes small, so that the amount of adsorption decreases.

  Examples of the hetero atom of the organic ligand capable of bidentate coordination in the present specification include a nitrogen atom, an oxygen atom, a phosphorus atom, and a sulfur atom.

  For example, 1,2-bis (4-pyridyl) ethyne has 2 heteroatoms, 1,4-bis (4-pyridyl) benzene has 2 heteroatoms, 3,6-di (4- Pyridyl) -1,2,4,5-tetrazine has 6 heteroatoms, N, N′-di (4-pyridyl) -1,4,5,8-naphthalenetetracarboxydiimide has Is 8 pieces.

  When the number of heteroatoms possessed by the organic ligand is 1, bidentate coordination cannot be performed with respect to the metal ion, and the three-dimensional structure of the target metal complex cannot be constructed. On the other hand, when the organic ligand capable of bidentate coordination has 6 or more heteroatoms, the charge density on the ligand constituting the pore wall is increased, and the mutual relationship between the gas molecule and the pore wall is increased. Since the effect is increased, the selectivity is lowered.

  Examples of the bidentate organic ligand include 1,2-bis (4-pyridyl) ethyne, 1,4-bis (4-pyridyl) benzene, and 4,4′-bis (4-pyridyl). Biphenyl can be mentioned, and 1,2-bis (4-pyridyl) ethyne is particularly preferable.

  The mixing ratio of the aromatic dicarboxylic acid compound and the bidentate organic ligand when producing the metal complex is as follows: aromatic dicarboxylic acid compound: bidentate organic ligand = 1: 5-8 Is preferably in the range of a molar ratio of 1: 1, more preferably in the range of a molar ratio of 1: 3 to 6: 1. Even if the reaction is carried out outside this range, the desired metal complex can be obtained, but this is not preferable because the yield decreases and the side reactions increase.

  The mixing ratio of the metal salt and the bidentate organic ligand when producing the metal complex is as follows: metal salt: bidentate organic ligand = 3: 1 to 1: 3 molar ratio Within the range, the molar ratio of 2: 1 to 1: 2 is more preferable. Outside this range, 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 aromatic dicarboxylic acid compound in the solvent 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 solvent 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 in the solvent for producing the metal complex is preferably 0.001 to 5.0 mol / L, more preferably 0.005 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.

  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.

  A metal complex having good crystallinity has high purity and good adsorption performance. 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 obtained as described above is an organic ligand capable of bidentate coordination to the axial position of the metal ion in the paddle wheel skeleton composed of the carboxylate ion and the metal ion of the aromatic dicarboxylic acid compound. Has a three-dimensional structure in which a jungle-gym skeleton formed by coordination is interpenetrated multiple times. A schematic diagram of the jungle gym skeleton is shown in FIG. 1, and a schematic diagram of a three-dimensional structure when the jungle gym skeleton is double-interpenetrated is shown in FIG.

  In this specification, the “jungle gym skeleton” is a coordination of an organic ligand capable of bidentate coordination to the axial position of a metal ion in a paddle wheel skeleton composed of a carboxylate ion and a metal ion of a dicarboxylic acid compound. In addition, it is defined as a jungle gym-like three-dimensional structure formed by connecting two-dimensional lattice-like sheets composed of a dicarboxylic acid compound 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 has multiple interpenetrations” can be confirmed by, for example, single crystal X-ray crystal structure analysis, powder X-ray crystal structure analysis, or the like.

  Since the three-dimensional structure in the metal complex of the present invention can be changed in the synthesized crystal, the structure and size of the pores change with the change. The conditions for changing the structure depend on the type of substance to be adsorbed, the adsorption pressure, and the adsorption temperature. In other words, 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 differs depending on the adsorbed substance, so high gas storage performance And high gas separation selectivity is exhibited. FIG. 3 shows a schematic diagram of the structural change accompanying the adsorption / desorption. After the adsorbed substance is desorbed, it returns to its original structure, so the pore size also returns. In addition, the metal complex of the present invention exhibits two-stage adsorption behavior because it has two types of pores: pores that are always accessible and pores that open above a certain pressure.

  Although the selective adsorption mechanism is estimated, 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 defined in the present invention.

  In the metal complex of the present invention, the accumulated structure of the metal complex and the size of the pores change depending on the type of the occluded substance, the occlusion pressure, or the occlusion temperature. Increases and reaches the maximum occlusion amount instantly. Since the pressure varies depending on the type of occluded substance or the occlusion temperature, carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, C 1-4 hydrocarbons (methane, ethane, ethylene, acetylene, etc.), rare It is preferable as an occlusion material for occlusion of gas (helium, neon, argon, krypton, xenon, etc.), hydrogen sulfide, ammonia, 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 can selectively adsorb various gases, carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, C 1-4 hydrocarbon (methane, ethane, ethylene, Acetylene), noble gases (such as helium, neon, argon, krypton, xenon), hydrogen sulfide, ammonia, sulfur oxides, nitrogen oxides, siloxanes (such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane), water vapor or It is also preferable as a separating material for separating organic vapors, etc., especially carbon dioxide in methane, carbon dioxide in hydrogen, carbon dioxide in nitrogen, ethane in methane or methane in air, etc. And suitable for separation by temperature swing adsorption method. 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, 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 crystal structure analysis The obtained single crystal was mounted on a gonio head and measured using a single crystal X-ray diffractometer.
Details of the measurement conditions are shown below.
<Analysis conditions>
Apparatus: SMART APEX II Ultra manufactured by Bruker AXS Co., Ltd.
X-ray source: MoKα (λ = 0.10773Å) 50 kV 24 mA
Condenser mirror: Helios
Detector: CCD
Collimator: Φ0.42mm
Analysis software: SHELXTL

(2) Measurement of powder X-ray diffraction pattern Using an X-ray diffractometer, a range of diffraction angle (2θ) = 5 to 50 ° was scanned at a scanning speed of 1 ° / min, and measured by a symmetric reflection method. Details of the analysis 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 °

(3) Measurement of adsorption / desorption isotherm (273K)
The measurement was performed by the volume method using a high-pressure gas adsorption amount measuring device. At this time, prior to measurement, the sample was vacuum-dried at 373 K and 50 Pa for 8 hours to remove adsorbed water and the like. Details of the analysis conditions are shown below.
<Analysis conditions>
Apparatus: BELSORP-HP manufactured by Nippon Bell Co., Ltd.
Equilibrium waiting time: 500 seconds

(4) Measurement of adsorption / desorption isotherm (195K)
The measurement was performed by the volume method using a high-accuracy gas adsorption amount measuring apparatus. At this time, prior to measurement, the sample was vacuum-dried at 373 K and 50 Pa for 8 hours to remove adsorbed water and the like. Details of the analysis conditions are shown below.
<Analysis conditions>
Apparatus: BELSORP-max manufactured by Nippon Bell Co., Ltd.
Equilibrium waiting time: 500 seconds

<Synthesis Example 1>
Under a nitrogen atmosphere, zinc nitrate hexahydrate 2.81 g (9.5 mmol), 2,6-naphthalenedicarboxylic acid 2.05 g (9.5 mmol) and 1,2-bis (4-pyridyl) ethyne 0.852 g ( 4.7 mmol) was dissolved in 800 mL of a mixed solvent of N, N-dimethylformamide and ethanol consisting of N, N-dimethylformamide: ethanol = 1: 1 in a volume ratio and stirred at 363 K for 48 hours. The results of single crystal X-ray structural analysis of the obtained crystals are shown below. The crystal structure is shown in FIG. FIG. 4 shows that this complex forms a three-dimensional structure in which the jungle gym skeleton is triple interpenetrated. Moreover, the powder X-ray-diffraction pattern of the obtained metal complex is shown in FIG.
Triclinic (P-1)
a = 13.1196 (15) Å
b = 13.1238 (15) Å
c = 16.5456 (19) Å
α = 99.412 (2) °
β = 92.340 (2) °
γ = 91.763 (2) °
V = 2806.1 (6) Å ³
Z = 4
R = 0.0739
Rw = 0.127
The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it vacuum-dried at 373K and 50Pa for 8 hours, and obtained the target metal complex 2.97g (yield 85%). The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG. From the comparison between FIG. 5 and FIG. 6, it can be seen that the powder X-ray diffraction pattern is different before and after the adsorption and desorption of the synthetic solvent, so that the structure of the metal complex of the present invention dynamically changes with the adsorption and desorption.

<Synthesis Example 2>
Under a nitrogen atmosphere, zinc nitrate hexahydrate 4.37 g (15 mmol), 2,6-naphthalenedicarboxylic acid 3.18 g (15 mmol) and 1,4-bis (4-pyridyl) benzene 1.72 g (7.5 mmol) Was dissolved in 600 mL of a mixed solvent of N, N-dimethylformamide and benzene consisting of N, N-dimethylformamide: benzene = 1: 1 and stirred at 373 K for 24 hours. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it vacuum-dried at 373K and 50Pa for 8 hours, and obtained the target metal complex 4.02g (yield 68%). FIG. 7 shows a powder X-ray diffraction pattern of the obtained metal complex.

<Synthesis Example 3>
Under a nitrogen atmosphere, zinc nitrate hexahydrate 1.89 g (6.3 mmol), 4,4′-biphenyldicarboxylic acid 1.54 g (6.3 mmol) and 1,4-bis (4-pyridyl) benzene 0.74 g (3.2 mmol) was dissolved in 540 mL of a mixed solvent of N, N-dimethylformamide and ethanol consisting of N, N-dimethylformamide: ethanol = 1: 1 and stirred at 373 K for 24 hours. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it vacuum-dried at 373K and 50Pa for 8 hours, and obtained the target metal complex 2.39g (yield 90%). The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG.

<Comparative Synthesis Example 1>
Under a nitrogen atmosphere, 2.81 g (9.5 mmol) of zinc nitrate hexahydrate, 1.57 g (9.5 mmol) of terephthalic acid and 0.852 g (4.7 mmol) of 1,2-bis (4-pyridyl) ethyne were added. The mixture was dissolved in 800 mL of a mixed solvent of N, N-dimethylformamide and ethanol having a volume ratio of N, N-dimethylformamide: ethanol = 1: 1 and stirred at 363 K for 48 hours. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it vacuum-dried at 373K and 50Pa for 8 hours, and obtained 2.65g (yield 88%) of the target metal complex. The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG.

<Comparative Synthesis Example 2>
Under a nitrogen atmosphere, 2.81 g (9.5 mmol) of zinc nitrate hexahydrate, 1.57 g (9.5 mmol) of terephthalic acid and 1.10 g (4.7 mmol) of 1,4-bis (4-pyridyl) benzene were added. It 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 373 K for 24 hours. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it vacuum-dried at 373 K and 50 Pa for 8 hours, and obtained the target metal complex 3.01g (yield 92%). The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG.

<Comparative Synthesis Example 3>
Under a nitrogen atmosphere, 4.28 g (15 mmol) of zinc nitrate hexahydrate, 3.18 g (15 mmol) of 2,6-naphthalenedicarboxylic acid and 1.34 g of trans-1,2-bis (4-pyridyl) ethene (7. 4 mmol) was dissolved in 600 mL of N, N-dimethylformamide and stirred at 373 K for 24 hours. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it vacuum-dried at 373 K and 50 Pa for 8 hours, and obtained 4.61 g (yield 85%) of the target metal complex. The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG.

<Comparative Synthesis Example 4>
Under a nitrogen atmosphere, 2.81 g (9.5 mmol) of zinc nitrate hexahydrate, 2.05 g (9.5 mmol) of 2,6-naphthalenedicarboxylic acid and 0.739 g (4.7 mmol) of 4,4′-bipyridyl were added. The mixture was dissolved in 800 mL of a mixed solvent of N, N-dimethylformamide and ethanol having a volume ratio of N, N-dimethylformamide: ethanol = 1: 1 and stirred at 363 K for 48 hours. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it vacuum-dried at 373K and 50Pa for 8 hours, and obtained the target metal complex 3.09g (yield 91%). The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG.

<Comparative Synthesis Example 5>
Under nitrogen atmosphere, zinc nitrate hexahydrate 2.81 g (9.5 mmol), 2,6-naphthalenedicarboxylic acid 2.05 g (9.5 mmol) and 3,6-di (4-pyridyl) -1,2, 1.10 g (4.7 mmol) of 4,5-tetrazine was dissolved in 800 mL of a mixed solvent of N, N-dimethylformamide and ethanol composed of N, N-dimethylformamide: ethanol = 1: 1 in a volume ratio, and 24 at 363K. Stir for hours. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it vacuum-dried at 373K and 50Pa for 8 hours, and obtained the target metal complex 3.65g (yield 97%). FIG. 13 shows a powder X-ray diffraction pattern of the obtained metal complex.

<Comparative Synthesis Example 6>
Under nitrogen atmosphere, zinc nitrate hexahydrate 5.35 g (18 mmol), 2,6-naphthalenedicarboxylic acid 0.778 g (3.6 mmol) and N, N′-di (4-pyridyl) -1,4,5 , 8-Naphthalenetetracarboxydiimide (1.51 g, 3.6 mmol) was dissolved in 1800 mL of N, N-dimethylformamide and stirred at 353 K for 72 hours. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it vacuum-dried at 373K and 50Pa for 8 hours, and obtained the target metal complex 1.16g (yield 66%). The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG.

<Comparative Synthesis Example 7>
Under a nitrogen atmosphere, 2.81 g (9.5 mmol) of zinc nitrate hexahydrate, 2.29 g (9.5 mmol) of 4,4′-biphenyldicarboxylic acid and 3,6-di (4-pyridyl) -1,2 , 4,5-tetrazine 1.12 g (4.7 mmol) 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 373 K for 24 hours. did. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it vacuum-dried at 373K and 50Pa for 8 hours, and obtained the target metal complex 3.37g (yield 84%). FIG. 15 shows a powder X-ray diffraction pattern of the obtained metal complex.

<Comparative Synthesis Example 8>
Under a nitrogen atmosphere, zinc nitrate hexahydrate 2.81 g (9.5 mmol), 4,4′-terphenyldicarboxylic acid 2.05 g (9.5 mmol) and 1,2-bis (4-pyridyl) ethyne 852 g (4.7 mmol) was dissolved in 800 mL of a mixed solvent of N, N-dimethylformamide and ethanol consisting of N, N-dimethylformamide: ethanol = 1: 1 in a volume ratio and stirred at 363 K for 24 hours. However, the target metal complex was not obtained.

<Example 1>
FIG. 16 shows the results of measuring the adsorption / desorption isotherm of carbon dioxide at 273 K by the volumetric method for the metal complex obtained in Synthesis Example 1.

<Comparative Example 1>
FIG. 17 shows the results of measuring the adsorption / desorption isotherm of carbon dioxide at 273 K by the capacity method for the metal complex obtained in Comparative Synthesis Example 1.

<Comparative example 2>
FIG. 18 shows the results of measuring the adsorption / desorption isotherm of carbon dioxide at 273 K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 3.

<Comparative Example 3>
FIG. 19 shows the results of measuring the adsorption / desorption isotherm of carbon dioxide at 273 K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 4.

<Comparative example 4>
FIG. 20 shows the results of measuring the adsorption / desorption isotherm of carbon dioxide at 273 K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 6.

  From comparison between FIG. 16 and FIGS. 17 to 20, the metal complex of the present invention has a large effective storage amount of carbon dioxide in a pressure region of 0.1 MPa or more, and the adsorbed carbon dioxide is taken out by 0.1 MPa (normal pressure). Since it is not necessary to reduce the pressure to 0.1 MPa or less, less energy is required for regeneration. Therefore, it is clear that it is excellent as a storage material for carbon dioxide.

<Example 2>
FIG. 21 shows the results of measuring the adsorption / desorption isotherm of ethane at 273 K by the volumetric method for the metal complex obtained in Synthesis Example 1.

<Comparative Example 5>
FIG. 22 shows the results of measuring the adsorption / desorption isotherm of ethane at 273 K by the capacitance method for the metal complex obtained in Comparative Synthesis Example 1.

<Comparative Example 6>
FIG. 23 shows the results of measuring the adsorption / desorption isotherm of ethane at 273 K by the capacitance method for the metal complex obtained in Comparative Synthesis Example 4.

  From the comparison between FIG. 21 and FIGS. 22 to 23, it is clear that the metal complex of the present invention has a large amount of ethane occlusion and can maintain the amount of occlusion even at a low pressure, and therefore is excellent as an ethane occlusion material. .

<Example 3>
FIG. 24 shows the results of measuring the adsorption / desorption isotherm of ethylene at 273 K by the volumetric method for the metal complex obtained in Synthesis Example 1.

<Comparative Example 7>
FIG. 25 shows the results of measuring the adsorption / desorption isotherm of ethylene at 273 K by the capacitance method for the metal complex obtained in Comparative Synthesis Example 1.

<Comparative Example 8>
FIG. 26 shows the results of measuring the adsorption / desorption isotherm of ethylene at 273 K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 4.

  From the comparison between FIG. 24 and FIGS. 25 to 26, it is clear that the metal complex of the present invention has a large amount of occlusion of ethylene and can maintain the occlusion amount even at a low pressure, so that it is excellent as an occlusion material for ethylene. .

<Example 4>
FIG. 27 shows the results of measuring the adsorption and desorption isotherm of carbon dioxide at 273 K by the volumetric method for the metal complex obtained in Synthesis Example 2.

<Comparative Example 9>
FIG. 28 shows the results of measuring the adsorption / desorption isotherm of carbon dioxide at 273 K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 2.

<Comparative Example 10>
FIG. 29 shows the results of measuring the adsorption / desorption isotherm of carbon dioxide at 273 K by the capacity method for the metal complex obtained in Comparative Synthesis Example 5.

  From comparison between FIG. 27 and FIGS. 28 to 29, it is clear that the metal complex of the present invention is excellent as a carbon dioxide occlusion material because it has a large amount of occlusion of carbon dioxide.

<Example 5>
FIG. 30 shows the results of measuring the adsorption / desorption isotherm of carbon dioxide at 195 K by the volumetric method for the metal complex obtained in Synthesis Example 3.

<Comparative Example 11>
FIG. 31 shows the results of measuring the adsorption / desorption isotherm of carbon dioxide at 195 K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 7.

  From comparison between FIG. 30 and FIG. 31, it is clear that the metal complex of the present invention is excellent as a carbon dioxide storage material because it has a large storage amount of carbon dioxide.

<Example 6>
FIG. 32 shows the results of measuring the adsorption / desorption isotherm of ethane and methane at 273 K by the capacity method for the metal complex obtained in Synthesis Example 1.

<Comparative Example 12>
FIG. 33 shows the results of measuring the adsorption / desorption isotherm of ethane and methane at 273 K by the capacitance method for the metal complex obtained in Comparative Synthesis Example 1.

<Comparative Example 13>
FIG. 34 shows the results of measuring the adsorption and desorption isotherms of ethane and methane at 273 K by the capacity method for the metal complex obtained in Comparative Synthesis Example 4.

  From the comparison between FIG. 32 and FIGS. 33 to 34, it is clear that the metal complex of the present invention selectively adsorbs ethane and has a large amount of ethane adsorption, and thus is excellent as a separator for ethane and methane.

<Example 7>
FIG. 35 shows the results of measuring the adsorption and desorption isotherms of carbon dioxide and nitrogen at 273 K by the volumetric method for the metal complex obtained in Synthesis Example 1.

<Comparative example 14>
FIG. 36 shows the results of measuring the adsorption / desorption isotherm of carbon dioxide and nitrogen at 273 K by the volumetric method for the metal complex obtained in Comparative Synthesis Example 1.

<Comparative Example 15>
FIG. 37 shows the results of measuring the adsorption and desorption isotherms of carbon dioxide and nitrogen at 273 K by the capacity method for the metal complex obtained in Comparative Synthesis Example 4.

<Comparative Example 16>
FIG. 38 shows the results of measuring the adsorption and desorption isotherms of carbon dioxide and nitrogen at 273 K by the capacity method for the metal complex obtained in Comparative Synthesis Example 6.

  From the comparison between FIG. 35 and FIGS. 36 to 38, the metal complex of the present invention can selectively adsorb carbon dioxide and can be desorbed at 0.1 MPa (normal pressure), and the pressure is reduced to 0.1 MPa or less. Since it is not necessary, less energy is required for regeneration. Therefore, it is clear that it is excellent as a separator for carbon dioxide and nitrogen.

<Example 8>
FIG. 39 shows the results of measuring the adsorption and desorption isotherms of carbon dioxide and nitrogen at 273 K by the volumetric method for the metal complex obtained in Synthesis Example 2.

<Comparative Example 17>
FIG. 40 shows the results of measuring the adsorption and desorption isotherms of carbon dioxide and nitrogen at 273 K by the capacity method for the metal complex obtained in Comparative Synthesis Example 2.

  From comparison between FIG. 39 and FIG. 40, it is clear that the metal complex of the present invention selectively adsorbs carbon dioxide and has a large amount of adsorbed carbon dioxide, and thus is excellent as a separator for nitrogen and carbon dioxide. .

Claims (11)

An aromatic dicarboxylic acid compound having 10 or more carbon atoms constituting an aromatic ring and having 10 or more π electrons that are conjugated in a cyclic manner in the structural formula, the carboxyl groups being farthest from each other And at least one metal ion selected from ions of metals belonging to Groups 2 and 7-12 of the periodic table, a point cloud of _D∞h , and a length in the major axis direction of 8.0Å or more A metal complex comprising an organic ligand that is less than 16.0 Å and that can be bidentately coordinated to the metal ion having 2 to 5 heteroatoms. The aromatic dicarboxylic acid compound is represented by the following general formula (I):

(Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are the same or different and each is a hydrogen atom, an alkyl group optionally having 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). The metal complex described. The aromatic dicarboxylic acid compound is represented by the following general formula (II):

(Wherein R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are the same or different and each represents a hydrogen atom, an alkyl group which may have a substituent, or an alkoxy group. , Formyl group, acyloxy group, alkoxycarbonyl group, nitro group, cyano group, amino group, monoalkylamino group, dialkylamino group, acylamino group or halogen atom, R ⁸ and R ⁹ , or R ¹² and R ¹³ The metal complex according to claim 1, which is a dicarboxylic acid compound (II) represented by the above, which may form an alkylene group or an alkenylene group which may have a substituent together.   The organic ligand capable of bidentate coordination is selected from 1,2-bis (4-pyridyl) ethyne, 1,4-bis (4-pyridyl) benzene and 4,4′-bis (4-pyridyl) biphenyl The metal complex according to claim 1, wherein the metal complex is at least one kind.   The metal complex according to claim 1, wherein the metal ion is a zinc ion. The occlusion material which consists of a metal complex in any one of Claims 1-5.   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. 6. The occlusion material according to 6.   The separating material which consists of a metal complex in any one of Claims 1-5.   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 8, which is a separation material for separation.   The separation material according to claim 8, wherein the separation material is a separation material for separating methane and carbon dioxide, hydrogen and carbon dioxide, nitrogen and carbon dioxide, methane and ethane, or air and methane. An aromatic dicarboxylic acid compound having 10 or more carbon atoms constituting an aromatic ring and having 10 or more π electrons that are conjugated in a cyclic manner in the structural formula, the carboxyl groups being farthest from each other And at least one metal salt selected from the salts of metals belonging to Group 2 and Group 7-12 of the periodic table, the point group is _D∞ , and the length in the major axis direction is at least 8.0 mm The metal complex which is less than 16.0 and reacts with an organic ligand capable of bidentate coordination with the metal ion having 2 to 5 heteroatoms to precipitate a metal complex. A method for producing a metal complex.