JP2012056946A - Metal complex, and adsorbing material, storage material and separation material composed thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal complex having excellent gas adsorbing performance, gas storage performance and gas separation performance.SOLUTION: The metal complex comprises a dicarboxylic acid compound (I) expressed by general formula (I) (in the formula, Rto Rare each independently a hydrogen atom or the like), at least one of metal ions selected from ions of metals of group 2 and groups 7-12 of the periodic table, and an organic ligand having a point group of D, a long axis length of ≥8.0 Å and <15.5 Å and bidentately coordinatable with the metal ion having 6-12 hetero atoms (excluding 3,6-di(4-pyridyl)-1,2,4,5-tetrazine).

Description

  The present invention relates to a metal complex, and an adsorbent, an occlusion material, and a separation material comprising the same. More specifically, a specific dicarboxylic acid compound, at least one metal ion selected from ions 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 present invention relates to a metal complex composed of a ligand. 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.

  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. (For example, refer nonpatent literature 1). 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 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 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 fumaric acid, copper ion and pyrazine, a polymer metal complex composed of terephthalic acid, copper ion and pyrazine, and fumaric acid, rhodium ion and pyrazine. No mention is made of the effect of an organic ligand capable of bidentate coordination 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.

  4,4′-biphenyldicarboxylic acid, 2,7-pyrene dicarboxylic acid and 4,5,9,10-tetrahydropyrene-2,7-dicarboxylic acid, metal ions, and organic coordination capable of bidentate coordination with the metal ions A polymer metal complex comprising a ligand 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.

  4,4′-biphenyldicarboxylic acid, 2,7-pyrene dicarboxylic acid and 4,5,9,10-tetrahydropyrene-2,7-dicarboxylic acid, metal ions, and organic coordination capable of bidentate coordination with the metal ions A polymer metal complex comprising a ligand has been disclosed (see Patent Document 4). 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 influence of possible organic ligands on gas storage performance and mixed gas separation performance.

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 object of the present invention is to provide a gas adsorbent having a larger adsorption amount than the conventional one, a gas storage material having a larger effective occlusion amount than the conventional one, and a metal complex that can be used as a gas separation material having a higher separation performance than the conventional one. It is to provide.

  The present inventor has intensively studied, a specific dicarboxylic acid compound, 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 The present inventors have found that the above object can be achieved by a metal complex composed of a possible organic ligand, 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 , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ 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 ² and R ³ , or R ⁶ and R ⁷ Together may form an alkylene group or alkenylene group which may have a substituent.) And a dicarboxylic acid compound (I) represented by groups 2 and 7 to 12 in the periodic table. At least one metal ion selected from the ions of the metal to which it belongs, the point group is _D∞h , the length in the major axis direction is from 8.0 to less than 15.5, and from 6 to 6 heteroatoms 12 The metal ions in a bidentate coordination acceptable organic ligand having (However, 3,6-di (4-pyridyl) -1,2,4,5-tetrazine are excluded.) And metal complexes composed of.
(2) The bidentate organic ligand is represented by the following general formula (II):

(In the formula, R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ may be the same or different and each may have a hydrogen atom or a substituent. A good alkyl group, alkoxy group, formyl group, acyloxy group, alkoxycarbonyl group, nitro group, cyano group, amino group, monoalkylamino group, dialkylamino group, acylamino group or halogen atom. The metal according to (1), which is a 6-di (4-pyridyl) -benzo [1,2-c: 4,5-c ′] dipyrrole-1,3,5,7 (2H, 6H) -tetron derivative Complex.
(3) The metal complex according to any one of (1) to (2), wherein the metal ion is a zinc ion.
(4) An adsorbent comprising the metal complex according to any one of (1) to (3).
(5) 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 (4), which is an adsorbent for adsorbing organic vapor.
(6) An occlusion material comprising the metal complex according to any one of (1) to (3).
(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 (3).
(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 separator is methane and carbon dioxide, ethane and carbon dioxide, ethylene and carbon dioxide, hydrogen and carbon dioxide, nitrogen and carbon dioxide, methane and ethane, air and methane, ethane and ethylene, ethylene and acetylene, ethane The separation material according to (8), which is a separation material for separating propane, propane, propane and propene, or methane, ethane and propane.
(11) The dicarboxylic acid compound (I), at least one metal ion selected from ions of metals belonging to Group 2 and Group 7-12 of the periodic table, a point group of _D∞h , and a long axis An organic ligand having a length in the direction of 8.0 to less than 15.5 and having 6 to 12 heteroatoms and capable of bidentate coordination is reacted in a solvent to form a metal complex. The method for producing a metal complex according to (1), wherein the metal complex is deposited.

  According to the present invention, a specific dicarboxylic acid compound, at least one metal ion selected from ions 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. A metal complex comprising a ligand 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, the metal complex of the present invention includes 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 Alternatively, it can be used as a separating material for separating organic vapor.

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 of the metal complex obtained in Synthesis Example 1. FIG. 3 is a powder X-ray diffraction pattern of the metal complex obtained in Comparative Synthesis Example 1. FIG. 4 is a powder X-ray diffraction pattern of the metal complex obtained in Comparative Synthesis Example 2. FIG. 4 is a powder X-ray diffraction pattern of the metal complex obtained in Comparative Synthesis Example 3. FIG. 6 is a powder X-ray diffraction pattern of the metal complex obtained in Comparative Synthesis Example 4. FIG. 7 is a powder X-ray diffraction pattern of the metal complex obtained in Comparative Synthesis Example 5. FIG. It is the result of having measured the adsorption isotherm in 195K of a carbon dioxide by the capacitance method about the metal complex obtained by the synthesis example 1 and the comparative synthesis example 1. 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 1 and the comparative synthesis example 1. FIG. It is the result of having measured the adsorption-desorption isotherm in 195K of a carbon dioxide and methane about the metal complex obtained by the synthesis example 1 by the capacitance method. It is the result of having measured the adsorption-desorption isotherm of carbon dioxide and methane in 195K 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 195K of a carbon dioxide and methane about the metal complex obtained by the comparative synthesis example 2 by the capacitance method. It is the result of having measured the adsorption-desorption isotherm in 195K of a carbon dioxide and methane about the metal complex obtained by the comparative synthesis example 3 by the capacitance method. It is the result of having measured the adsorption-desorption isotherm of carbon dioxide and methane in 195K 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 195K of a carbon dioxide and methane about the metal complex obtained by the comparative synthesis example 5 by the capacitance method.

The metal complex used in the present invention comprises a dicarboxylic acid compound (I), at least one metal ion selected from ions of metals belonging to Groups 2 and 7-12 of the periodic table, and a point group of _D∞h . And an organic ligand having a length in the major axis direction of from 8.0 to less than 15.5 and capable of bidentate coordination with the metal ion having 6 to 12 heteroatoms.

The metal complex is composed of a dicarboxylic acid compound (I), 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∞ , and a long An organic ligand having an axial length of 8.0 to less than 15.5 and capable of bidentate coordination with the metal ion having 6 to 12 heteroatoms in a solvent under normal pressure. It can be produced by reacting for several days from the time and depositing. For example, it is obtained 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 (I) and an organic ligand capable of bidentate coordination under normal pressure. Can do.

  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 , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are the same or different and each is a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, A formyl group, an acyloxy group, an alkoxycarbonyl group, a nitro group, a cyano group, an amino group, a monoalkylamino group, a dialkylamino group, an acylamino group, or a halogen atom, R ² and R ³ , or R ⁶ and R ⁷ are An alkylene group or alkenylene group which may have a substituent may be formed together.

Among the substituents that can constitute R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ , 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.

The number of carbon atoms of the alkylene group is preferably 1 or 2. When the alkylene group has 1 carbon atom, R ² and R ³ , or R ⁶ and R ⁷ together with the carbon atom to which they are bonded form a 5-membered ring (cyclopentadiene ring), and the alkylene group When R ² has 2 carbon atoms, R ² and R ³ , or R ⁶ and R ⁷ together with the carbon atom to which they are bonded form a 6-membered ring (cyclohexadiene ring).

The alkenylene group preferably has 2 carbon atoms. When the alkenylene group has 2 carbon atoms, R ² and R ³ , or R ⁶ and R ⁷ together with the carbon atom to which they are bonded form a 6-membered ring (benzene ring).

  Examples of the substituent that the alkylene group or 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 (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 an alkyl group having 1 to 5 carbon atoms).

  Examples of the dicarboxylic acid compound (I) include 4,4′-biphenyldicarboxylic acid, 2,7-fluorenedicarboxylic acid, 2,7-pyrene dicarboxylic acid, and 4,5,9,10-tetrahydropyrene-2,7. -Dicarboxylic acids can be used, among which 4,4'-biphenyldicarboxylic acid is preferred.

  Examples of ions of metals belonging to Groups 2 and 7-12 of the periodic table include magnesium ions, calcium ions, chromium ions, molybdenum ions, tungsten ions, manganese ions, iron ions, ruthenium ions, cobalt ions, rhodium ions, Nickel ion, palladium ion, copper ion, zinc ion and cadmium ion can be used, among which magnesium ion, manganese ion, cobalt ion, nickel ion, copper ion, zinc ion and cadmium ion are preferable, and zinc ion is more preferable. .

  Examples of the metal salt used in the production of the metal complex include magnesium salt, calcium salt, chromium salt, molybdenum salt, tungsten salt, manganese salt, iron salt, ruthenium salt, cobalt salt, rhodium salt, nickel salt, palladium salt, copper Salts, zinc salts and cadmium salts can be used, among which magnesium salts, manganese salts, cobalt salts, nickel salts, copper salts, zinc salts and cadmium salts are preferable, and zinc salts are 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 be used in mixture of 2 or more types of the metal complex which consists of a single metal. 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 point group used in the present invention is D _∞h , the length in the major axis direction is 8.0 to less than 15.5 and bidentate coordination to the metal ion having 6 to 12 heteroatoms Possible organic ligands are the following general formula (II):

It is represented by In the formula, R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ , and R ¹⁸ may be the same or different and each may have a hydrogen atom or a substituent. Good alkyl group, alkoxy group, formyl group, acyloxy group, alkoxycarbonyl group, nitro group, cyano group, amino group, monoalkylamino group, dialkylamino group, acylamino group or halogen atom, preferably hydrogen atom, substituent Or an alkyl group which may have a halogen atom or a halogen atom.

Among the substituents that can constitute R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ , and R ¹⁸ , the alkyl group has 1 to 1 carbon atoms. 5 is preferred. 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-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 And 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 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 15.5, and from 6 to 6 heteroatoms. I have twelve. 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, 4,4′-bis (4-pyridyl) biphenyl, 3,6-di (4-pyridyl)- 1,2,4,5-tetrazine and 2,6-di (4-pyridyl) -benzo [1,2-c: 4,5-c ′] dipyrrole-1,3,5,7 (2H, 6H) -Tetron is a symmetric linear molecule and has a symmetrical center, so 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.

  In this specification, the length in the major axis direction of the organic ligand capable of bidentate coordination was measured using molecular dynamics method MM3 using Sigles Explorer Professional Version 7.6.0.52 manufactured by Fujitsu Limited. 2 atoms at the most distant positions in the structural formula among the atoms that can coordinate to the metal ion in the most stable structure obtained by performing the structure optimization by the semi-empirical molecular orbital method PM5 It is defined as the distance between the centers.

  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 11.204Å, 2,6-di (4-pyridyl) -benzo [1,2-c: 4,5-c ′]. The distance between nitrogen atoms of dipyrrole-1,3,5,7 (2H, 6H) -tetron is 15.182Å, the distance between nitrogen atoms of 4,4′-bis (4-pyridyl) biphenylene is 15.570Å, N, N′-di (4-pyridyl) -1,4,5,8 Nitrogen interatomic distance naphthalene tetracarboxylic diimide becomes 15.533A.

  When the length in the long axis direction of the organic ligand capable of bidentate coordination is less than 8.0 mm, the pore volume becomes too small, and the adsorption amount decreases. On the other hand, when the length in the major axis direction is 15.5 mm or more, the pore diameter becomes too large and the molecular sieving effect is lost, so the selectivity is lowered.

  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 and 2,6-di (4-pyridyl) -benzo [1,2-c: 4,5-c ′] dipyrrole-1 , 3,5,7 (2H, 6H) -Tetron has 8 heteroatoms, N, N′-di (4-pyridyl) -1,4,5,8-naphthalenetetracarboxydiimide has heteroatoms The number is eight.

  The number of heteroatoms contained in the bidentate organic ligand is preferably 6-12, more preferably 6-10, and even more preferably 6-8. When the number of heteroatoms of an organic ligand capable of bidentate coordination is 5 or less, the charge density on the ligand constituting the pore wall is small and the interaction between the gas molecule and the pore wall is small. Therefore, the amount of adsorption decreases. On the other hand, when the organic ligand capable of bidentate coordination has 13 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.

  As an organic ligand capable of bidentate coordination, for example, 2,6-di (4-pyridyl) -benzo [1,2-c: 4,5-c ′] dipyrrole-1,3,5,7 (2H, 6H) -Tetron can be used.

  The mixing ratio of the dicarboxylic acid compound (I) to the bidentate organic ligand when producing the metal complex is as follows: dicarboxylic acid compound (I): bidentate organic ligand = 1: A molar ratio in the range of 5-8: 1 is preferred, and a molar ratio in the range of 1: 3-6: 1 is more preferred. 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 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. 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 in the mixed solution for producing the metal complex is preferably 0.001 to 5.0 mol / L, and 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 coordination 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 dicarboxylic acid compound (I). It has a three-dimensional structure in which jungle gym skeletons formed by coordination of children are interpenetrated multiple times.

  In this specification, the “jungle gym skeleton” is an organic ligand capable of bidentate coordination at the axial position of the metal ion in the paddle wheel skeleton composed of the carboxylate ion and the metal ion of the dicarboxylic acid compound (I). It is defined as a jungle-gym-like three-dimensional structure formed by coordination and connection between two-dimensional lattice sheets made 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 two or more jungle gym skeletons penetrate each other so as to fill the pores of each other.

  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 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. FIG. 1 shows a schematic diagram of the structural change accompanying adsorption / desorption. In the present invention, the dicarboxylic acid compound represented by the general formula (I) and the point group are D _∞h , the length in the major axis direction is from 8.0 to less than 15.5 and the heteroatoms are 6 High gas adsorption performance, high gas storage performance, and high gas separation performance are manifested by controlling the pore shape and the charge density on the surface of the pores using ~ 12 bidentate organic ligands . 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.

  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 and triethylamine; aldehydes such as acetaldehyde; aliphatic hydrocarbons having 5 to 16 carbon atoms; aromatic hydrocarbons such as benzene and toluene. Ketones such as acetone and methyl ethyl ketone; halogenated hydrocarbons such as methyl chloride, methylene 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 also 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 can selectively adsorb various gases, carbon dioxide, hydrogen, carbon monoxide, oxygen, nitrogen, C 1-4 hydrocarbons (methane, ethane, ethylene, Acetylene, propane, propene, methylacetylene, propadiene, etc.), noble gases (such as helium, neon, argon, krypton, xenon), hydrogen sulfide, ammonia, sulfur oxide, nitrogen oxide, siloxane (hexamethylcyclotrisiloxane, octane) Methylcyclotetrasiloxane, etc.), preferable as a separating material for separating water vapor or organic vapor, etc., particularly carbon dioxide in methane, carbon dioxide in ethane, carbon dioxide in ethylene, carbon dioxide in hydrogen, nitrogen Carbon dioxide, ethane in methane, methane in air, ethylene in ethane, ethane Acetylene in Ren, propane ethane, the ethane and propane propene or methane 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, 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) Measurement of powder X-ray diffraction pattern Using a powder 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 °

(2) Measurement of adsorption / desorption isotherm Measurement was performed by a volumetric method using a gas adsorption amount measuring device. At this time, prior to the measurement, the sample was 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>
Device: Nippon Bell Co., Ltd. BELSORP-18PLUS
Equilibrium waiting time: 500 seconds

<Synthesis Example 1>
Under a nitrogen atmosphere, zinc nitrate hexahydrate 2.81 g (9.5 mmol), 4,4′-biphenyldicarboxylic acid 2.29 g (9.5 mmol) and 2,6-di (4-pyridyl) -benzo [1 , 2-c: 4,5-c ′] dipyrrole-1,3,5,7 (2H, 6H) -tetron 1.75 g (4.7 mmol) in a volume ratio of N, N-dimethylformamide: ethanol = 1 1 was dissolved in 800 mL of a mixed solvent of N, N-dimethylformamide and ethanol consisting of 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 dried at 373 K and 50 Pa for 8 hours, and obtained the target metal complex 4.32g (yield 93%). The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG.

<Comparative Synthesis Example 1>
Under a nitrogen atmosphere, zinc nitrate hexahydrate 2.81 g (9.5 mmol), 4,4′-biphenyldicarboxylic acid 2.29 g (9.5 mmol) and 4,4′-bipyridyl 0.75 g (4.7 mmol) 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 24 hours. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it dried at 373K and 50 Pa for 8 hours, and obtained the target metal complex 3.24g (yield 89%). The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG.

<Comparative Synthesis Example 2>
Under a nitrogen atmosphere, zinc nitrate hexahydrate 2.81 g (9.5 mmol), 4,4′-biphenyldicarboxylic acid 2.29 g (9.5 mmol) and 1,2-bis (4-pyridyl) ethyne 0.852 g (4.7 mmol) was dissolved in a volume ratio of N, N-dimethylformamide: ethanol = 1: 1 mixed solvent of N, N-dimethylformamide and ethanol (800 mL) and stirred at 363 K for 24 hours. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it dried at 373K and 50 Pa for 8 hours, and obtained the target metal complex 3.04g (yield 81%). The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG.

<Comparative Synthesis Example 3>
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 at a volume ratio of 363 K. Stir for 24 hours. 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 3.37g (yield 84%). FIG. 5 shows a powder X-ray diffraction pattern of the obtained metal complex.

<Comparative Synthesis Example 4>
In a nitrogen atmosphere, 1.49 g (5.0 mmol) of zinc nitrate hexahydrate, 1.21 g (5.0 mmol) of 4,4′-biphenyldicarboxylic acid and N, N′-di (4-pyridyl) -1, 1.05 g (2.5 mmol) of 4,5,8-naphthalenetetracarboxydiimide was dissolved in 500 mL of N, N-dimethylformamide and stirred at 413 K for 48 hours. The precipitated metal complex was recovered by suction filtration, and then washed with methanol three times. Then, it dried at 373K and 50 Pa for 8 hours, and obtained the target metal complex 1.82g (yield 70%). The powder X-ray diffraction pattern of the obtained metal complex is shown in FIG.

<Comparative Synthesis Example 5>
Under a nitrogen atmosphere, zinc nitrate hexahydrate 2.81 g (9.5 mmol), terephthalic acid 1.57 g (9.5 mmol) and 2,6-di (4-pyridyl) -benzo [1,2-c: 4 , 5-c ′] dipyrrole-1,3,5,7 (2H, 6H) -tetron 1.75 g (4.7 mmol) in a volume ratio of N, N-dimethylformamide: ethanol = 1: 1 The mixture was dissolved in 800 mL of a mixed solvent of N-dimethylformamide and ethanol 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 dried at 373 K and 50 Pa for 8 hours, and obtained the objective metal complex 3.72g (yield 95%). FIG. 7 shows a powder X-ray diffraction pattern of the obtained metal complex.

<Example 1>
For the metal complex obtained in Synthesis Example 1, the adsorption isotherm of carbon dioxide at 195 K was measured. The results are shown in FIG.

<Comparative Example 1>
The adsorption complex isotherm of carbon dioxide at 195K was measured for the metal complex obtained in Comparative Synthesis Example 1. The results are shown in FIG.

  FIG. 8 clearly shows that the metal complex of the present invention is excellent as an adsorbent for carbon dioxide because it has a large amount of carbon dioxide adsorbed.

<Example 2>
For the metal complex obtained in Synthesis Example 1, the adsorption and desorption isotherm of carbon dioxide at 195 K was measured. The results are shown in FIG.

<Comparative example 2>
For the metal complex obtained in Comparative Synthesis Example 1, the adsorption and desorption isotherm of carbon dioxide at 195 K was measured. The results are shown in FIG.

  From FIG. 9, 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 3>
For the metal complex obtained in Synthesis Example 1, the adsorption and desorption isotherms of carbon dioxide and methane at 195 K were measured. The results are shown in FIG.

<Comparative Example 3>
For the metal complex obtained in Comparative Synthesis Example 1, the adsorption and desorption isotherms of carbon dioxide and methane at 195 K were measured. The results are shown in FIG.

<Comparative example 4>
For the metal complex obtained in Comparative Synthesis Example 2, the adsorption and desorption isotherms of carbon dioxide and methane at 195 K were measured. The results are shown in FIG.

<Comparative Example 5>
The adsorption and desorption isotherms of carbon dioxide and methane at 195 K were measured for the metal complex obtained in Comparative Synthesis Example 3. The results are shown in FIG.

<Comparative Example 6>
For the metal complex obtained in Comparative Synthesis Example 4, the adsorption and desorption isotherms of carbon dioxide and methane at 195 K were measured. The results are shown in FIG.

<Comparative Example 7>
For the metal complex obtained in Comparative Synthesis Example 5, adsorption / desorption isotherms of carbon dioxide and methane at 195 K were measured. The results are shown in FIG.

  From the comparison between FIG. 10 and FIGS. 11 to 15, it is clear that the metal complex of the present invention selectively adsorbs carbon dioxide and has a large amount of carbon dioxide adsorption, and thus is excellent as a separator for methane and carbon dioxide. It is.

Claims (11)

The following general formula (I);
(Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ 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 ² and R ³ , or R ⁶ and R ⁷ Together may form an alkylene group or alkenylene group which may have a substituent.) And a dicarboxylic acid compound (I) represented by groups 2 and 7 to 12 in the periodic table. At least one metal ion selected from the ions of the metal to which it belongs, the point group is _D∞h , the length in the major axis direction is from 8.0 to less than 15.5, and from 6 to 6 heteroatoms 12 The metal ions in a bidentate coordination acceptable organic ligand having (However, 3,6-di (4-pyridyl) -1,2,4,5-tetrazine are excluded.) And metal complexes composed of. The organic ligand capable of bidentate coordination is represented by the following general formula (II):
(In the formula, R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ may be the same or different and each may have a hydrogen atom or a substituent. A good alkyl group, alkoxy group, formyl group, acyloxy group, alkoxycarbonyl group, nitro group, cyano group, amino group, monoalkylamino group, dialkylamino group, acylamino group or halogen atom. The metal according to claim 1, which is a 6-di (4-pyridyl) -benzo [1,2-c: 4,5-c '] dipyrrole-1,3,5,7 (2H, 6H) -tetron derivative. Complex.   The metal complex according to claim 1, wherein the metal ion is a zinc ion. The adsorbent which consists of a metal complex in any one of Claims 1-3. 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 4, which is an adsorbent for adsorbing.   The occlusion material which consists of a metal complex in any one of Claims 1-3. 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 1-3. 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 separator is methane and carbon dioxide, ethylene and carbon dioxide, hydrogen and carbon dioxide, nitrogen and carbon dioxide, air and methane, methane and ethane, ethane and propane, propane and propene, ethylene and ethane, ethylene and acetylene, or The separation material according to claim 8, which is a separation material for separating methane, ethane and propane. A dicarboxylic acid compound (I), 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 length An organic ligand capable of bidentate coordination with the metal ion having a length of 8.0 to less than 15.5 and having 6 to 12 heteroatoms in a solvent to precipitate a metal complex. The manufacturing method of the metal complex of Claim 1.