Metal-organic frameworks with terephthalic acid ligands

Abstract

The invention addresses the problem that metal-organic frameworks have conventionally only been produced with terephthalic acids having a limited range of substituents even though the amount and type of gas stored thereby can vary depending on the type of substituents. The objective of the present invention is to provide a novel metal-organic framework using a 2,5-disubstituted terephthalic acid. The metal-organic framework obtained through the binding of a carboxylic acid ion represented by formula (I) with a polyvalent metal ion, is a novel metal-organic framework and is capable of storing gases such as hydrogen and nitrogen efficiently. (In formula (I), X represents an unsubstituted or a substituted cycloalkyl group, an unsubstituted or a substituted aryl group, an unsubstituted or a substituted heterocyclyl group, or -Si(R1)(R2)(R3), and Y represents a single bond, an alkylene group, -O-, -S-, -S(O)-, -SO2-, or -N(R4)-, or a group combining these, with the proviso that phenyl groups, benzyloxy groups, pyrazole-1-yl groups, and groups represented by formula (II) when m equals 3, 6, 8, 9, 10, 11 and 12, are excluded as X-Y-.)

Description

[Technical field]

[0001] The present invention relates to a novel metal-organic framework and a method for storing gas using such a metal-organic framework. This application claims priority based on Japanese Patent Application No. 2019-117163, filed on June 25, 2019, the contents of which are incorporated herein by reference. [Background technology]

[0002] Metal-organic frameworks (hereinafter sometimes referred to as "MOFs") are solid substances that have a polymer structure with internal spaces (i.e., pores) created by combining metal ions with bridging organic ligands that link them. They have attracted great interest over the past decade as porous materials with functions such as gas storage and separation. As the crosslinkable organic ligands, oxygen donor ligands and nitrogen donor ligands have been widely used.

[0003] It is known that MOF-5, which is obtained by a solvothermal method using Zn(NO3)2·6H2O in N,N-dimethylformamide using terephthalic acid as a bridging organic ligand, can store 7.1 mass% hydrogen relative to MOF-5 at a temperature of 77 K and a pressure of 4 MPa (see Non-Patent Documents 1 to 3).

[0004] It is also known that an isoreticular metal-organic framework (IRMOF) having the same structure as MOF-5 can be obtained by using a terephthalic acid derivative having an n-propoxy group or an n-pentoxy group at the 2,5-position of terephthalic acid (see Non-Patent Document 2).

[0005] As examples of MOFs using 2,5-disubstituted terephthalic acid, there are known MOFs using terephthalic acid as an organic ligand having an ω-(carbazol-9-yl)alkoxy group (the number of carbon atoms in the alkylene chain is 3, 6, and 8-12) (see Non-Patent Documents 4 and 5), an alkoxy group (the number of carbon atoms is 6-14) (see Non-Patent Document 6), a methyl group, a methoxy group, a chloro group, an ethyl group, and an ethoxy group (see Patent Document 1), a hydroxy group and an acetoxy group (see Non-Patent Document 7), an isopropoxy group, an allyloxy group, and a propargyloxy group (see Non-Patent Document 8), a pyrazol-1-yl group (see Non-Patent Document 9), a 4-methylbenzoyl group (see Non-Patent Document 10), a benzoyl group (see Non-Patent Document 11), a benzyloxy group (see Non-Patent Document 12), a bromo group (see Non-Patent Document 13), and a phenyl group (see Non-Patent Document 14) at the 2- and 5-positions. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Patent Publication No. 2010-75123 [Non-patent literature]

[0007] [Non-Patent Document 1] H. Li, M. Eddaudi, M. O'Keefe, OM Yaghi, Nature, 402, 276(1999) [Non-Patent Document 2] M. Eddaudi, J. Kim, N. Rosi, D. Vodak, J. Wachter, M. O'Keefe, OM Yaghi, Science 2002, 295(5554), 469. [Non-Patent Document 3] S. Kaye, A. Daily, OM Yaghi, J. Long, J. Am. Chem. Soc. 2007, 129(46), 14176. [Non-Patent Document 4] EY Choi, SH Lee, OP Kwon, Bull. Korean Chem. Soc. 2012, 33(7), 2431.

Non-licensed Document 5

Non-licensed Document 6

Non-licensed Document 7

Non-licensed Document 8

Non-licensed literature 9

Non-licensed literature 10

Non-licensed Document 11

[0008] As described in Non-Patent Document 8, the amount and type of gas stored can change depending on the type of substituent. However, only MOFs using terephthalic acid with the limited range of substituents described above have been produced so far. An object of the present invention is to provide a novel MOF using 2,5-disubstituted terephthalic acid. [Means for solving the problem]

[0009] As a result of intensive research aimed at solving the above problems, the inventors discovered that a novel MOF can be provided by using an unprecedented combination of 2,5-disubstituted terephthalic acid and various metal salts, thereby completing the present invention.

[0010] That is, the present invention is as follows, which is specified by the following items. [1] A metal organic framework formed by bonding a carboxylate ion represented by formula (I) and a polyvalent metal ion. [ka] (In formula (I), X is an unsubstituted or substituted cycloalkyl group, an unsubstituted or substituted aryl group, an unsubstituted or substituted heterocyclyl group, or -Si(R 1 )(R 2 )(R 3 ), and R 1 ~R 3 each independently represents a hydrogen atom, an unsubstituted or substituted alkyl group, or an unsubstituted or substituted aryl group; Y is a single bond, an alkylene group, -O-, -S-, -S(O)-, -SO2-, -N(R 4 )- or a combination thereof, R 4 represents a hydrogen atom, an unsubstituted or substituted alkyl group, an unsubstituted or substituted cycloalkyl group, an unsubstituted or substituted arylalkyl group, an unsubstituted or substituted aryl group, or an unsubstituted or substituted heterocyclyl group. However, XY- does not include a phenyl group, a benzyloxy group, a pyrazol-1-yl group, or a group represented by formula (II) in which m is 3, 6, 8, 9, 10, 11, or 12. [ka] [2] The metal organic structure according to [1], wherein the polyvalent metal ion is an ion of at least one metal selected from the group consisting of metals in groups 2 to 13 of the periodic table. [3] The metal organic structure according to [1] or [2], wherein the polyvalent metal ion is an ion of at least one metal selected from Zn, Fe, Co, Ni, Cu, Al, Zr, and Mg. [4] The metal organic structure according to any one of [1] to [3], further comprising an organic ligand other than the organic ligand represented by formula (I) as a constituent component. [5] A gas storage method comprising the steps of contacting a gas with the metal-organic framework according to any one of [1] to [4] and adsorbing the gas inside the metal-organic framework. Effect of the Invention

[0011] The MOF of the present invention is a novel MOF and may exhibit different performance in gas storage than conventional MOFs. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The MOF of the present invention is an MOF in which a carboxylate ion represented by formula (I) is bonded to a polyvalent metal ion. The polyvalent metal ion used in the present invention is not particularly limited as long as it is an ion of a divalent or higher metal, but is preferably an ion of at least one metal selected from the group consisting of metals of groups 2 to 13 of the periodic table, more preferably an ion of at least one metal selected from Zn, Fe, Co, Ni, Cu, Al, Zr, and Mg, and further preferably an ion of at least one metal selected from Co, Ni, Cu, and Zn.

[0013] These polyvalent metal ions are supplied in the form of various salts, examples of which include nitrates, perchlorates, and chloride ion salts, and specific examples include Zn(NO3)2·6H2O, Zn(NO3)2·4H2O, Ni(NO3)2·6H2O, Mg(NO3)2·6H2O, Cu(NO3)2·xH2O, Cu(NO3)2·2.5H2O, Co(NO3)2·6H2O, Al(NO3)3·6H2O, and ZrCl4. Furthermore, in consideration of the purity of the salt, the ease of bonding between the metal ion and the organic ligand, and the like, nitrates are a preferred example.

[0014] The MOF of the present invention comprises a carboxylate ion represented by formula (I). In formula (I), X is an unsubstituted or substituted cycloalkyl group, an unsubstituted or substituted aryl group, an unsubstituted or substituted heterocyclyl group, or -Si(R 1 )(R2 )(R 3 )

[0015] Here, in the present invention, the term "unsubstituted" means that only the group that serves as the mother nucleus is present. When there is no description of "substituted" and only the name of the group that serves as the mother nucleus is described, it means "unsubstituted" unless otherwise specified. On the other hand, "substituted" means that any hydrogen atom of the group serving as the mother nucleus is replaced with a functional group (substituent) having the same or different structure as the mother nucleus. Therefore, a "substituent" is another functional group bonded to the functional group serving as the mother nucleus. The number of the substituents may be one or more. The two or more substituents may be the same or different. The term "C1-6" indicates that the core group (the functional group next to the term "C1-6") has 1 to 6 carbon atoms. This number of carbon atoms does not include the number of carbon atoms in the substituent. For example, a butyl group having an ethoxy group as a substituent is classified as a C2 alkoxy C4 alkyl group.

[0016] The "substituent" is not particularly limited as long as it is chemically permissible and has the effect of the present invention. Examples of groups that can be the "substituent" are shown below. C1 to C6 alkyl groups such as a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an s-butyl group, an i-butyl group, a t-butyl group, an n-pentyl group, or an n-hexyl group; C2-6 alkenyl groups, such as a vinyl group, a 1-propenyl group, a 2-propenyl group (allyl group), a 1-butenyl group, a 2-butenyl group, a 3-butenyl group, a 1-methyl-2-propenyl group, or a 2-methyl-2-propenyl group; C2-6 alkynyl groups, such as an ethynyl group, a 1-propynyl group, a 2-propynyl group (propargyl group), a 1-butynyl group, a 2-butynyl group, a 3-butynyl group, or a 1-methyl-2-propynyl group;

[0017] C3-8 cycloalkyl groups such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cubanyl group; C6-10 aryl groups such as phenyl and naphthyl groups; C6-10 aryl C1-6 alkyl groups such as a benzyl group and a phenethyl group; 3- to 6-membered heterocyclyl groups; 3-6 membered heterocyclyl C1-6 alkyl group;

[0018] oxo group; Hydroxyl; C1 to C6 alkoxy groups, such as a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, an n-butoxy group, an s-butoxy group, an i-butoxy group, or a t-butoxy group; C2 to C6 alkenyloxy groups, such as a vinyloxy group, an allyloxy group, a propenyloxy group, or a butenyloxy group; C2-6 alkynyloxy groups such as an ethynyloxy group or a propargyloxy group; C6-10 aryloxy groups such as a phenoxy group and a naphthoxy group; C6-10 aryl C1-6 alkoxy groups, such as a benzyloxy group or a phenethyloxy group; 5- to 6-membered heteroaryloxy groups such as a thiazolyloxy group and a pyridyloxy group; 5- to 6-membered heteroaryl C1-6 alkyloxy groups such as a thiazolylmethyloxy group and a pyridylmethyloxy group;

[0019] Formyl group; C1-6 alkylcarbonyl groups such as an acetyl group or a propionyl group; Formyloxy group; C1-6 alkylcarbonyloxy groups such as an acetyloxy group or a propionyloxy group; C6-10 arylcarbonyl groups such as benzoyl groups; C1-6 alkoxycarbonyl groups, such as a methoxycarbonyl group, an ethoxycarbonyl group, an n-propoxycarbonyl group, an i-propoxycarbonyl group, an n-butoxycarbonyl group, or a t-butoxycarbonyl group; C1-6 alkoxycarbonyloxy groups, such as a methoxycarbonyloxy group, an ethoxycarbonyloxy group, an n-propoxycarbonyloxy group, an i-propoxycarbonyloxy group, an n-butoxycarbonyloxy group, or a t-butoxycarbonyloxy group; Carboxy group;

[0020] halogeno groups such as a fluoro group, a chloro group, a bromo group, or an iodo group; C1-6 haloalkyl groups such as a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a 2,2,2-trifluoroethyl group, a pentafluoroethyl group, a 3,3,3-trifluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluoropropyl group, a 2,2,2-trifluoro-1-trifluoromethylethyl group, a perfluoroisopropyl group, a 4-fluorobutyl group, a 2,2,3,3,4,4,4-heptafluorobutyl group, a perfluorobutyl group, a perfluoropentyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, a dichloromethyl group, a dibromomethyl group, a trichloromethyl group, a tribromomethyl group, a 1-chloroethyl group, a 2,2,2-trichloroethyl group, a 4-chlorobutyl group, a perchlorohexyl group, and a 2,4,6-trichlorohexyl group; C2-6 haloalkenyl groups such as a 2-chloro-1-propenyl group and a 2-fluoro-1-butenyl group; C2 to C6 haloalkynyl groups, such as a 4,4-dichloro-1-butynyl group, a 4-fluoro-1-pentynyl group, or a 5-bromo-2-pentynyl group; C1 to 6 haloalkoxy groups, such as a trifluoromethoxy group, a 2-chloro-n-propoxy group, or a 2,3-dichlorobutoxy group; C2-6 haloalkenyloxy groups, such as a 2-chloropropenyloxy group or a 3-bromobutenyloxy group; C1-6 haloalkylcarbonyl groups such as a chloroacetyl group, a trifluoroacetyl group, or a trichloroacetyl group;

[0021] Amino group; C1-6 alkyl-substituted amino groups such as methylamino group, dimethylamino group, and diethylamino group; C6-10 arylamino groups such as anilino group and naphthylamino group; C6-10 aryl C1-6 alkylamino groups, such as a benzylamino group or a phenethylamino group; Formylamino group; C1-6 alkylcarbonylamino groups, such as an acetylamino group, a propanoylamino group, a butyrylamino group, or an i-propylcarbonylamino group; C1-6 alkoxycarbonylamino groups, such as a methoxycarbonylamino group, an ethoxycarbonylamino group, an n-propoxycarbonylamino group, or an i-propoxycarbonylamino group; C1 to 6 alkylsulfoximino groups such as S,S-dimethylsulfoximino group; unsubstituted or substituted aminocarbonyl groups, such as an aminocarbonyl group, a dimethylaminocarbonyl group, a phenylaminocarbonyl group, or an N-phenyl-N-methylaminocarbonyl group; imino C1-6 alkyl group such as an iminomethyl group, a 1-iminoethyl group, or a 1-imino-n-propyl group; substituted or unsubstituted N-hydroxyimino C1-6 alkyl groups, such as an N-hydroxy-iminomethyl group, a 1-(N-hydroxyimino)ethyl group, a 1-(N-hydroxyimino)propyl group, an N-methoxyiminomethyl group, or a 1-(N-methoxyimino)ethyl group; Hydroxyimino group; C1 to C6 alkoxyimino groups, such as a methoxyimino group, an ethoxyimino group, an n-propoxyimino group, an i-propoxyimino group, or an n-butoxyimino group; Aminocarbonyloxy group; C1-6 alkyl-substituted aminocarbonyloxy groups, such as an ethylaminocarbonyloxy group or a dimethylaminocarbonyloxy group;

[0022] Thioxo group Mercapto group; C1 to C6 alkylthio groups, such as a methylthio group, an ethylthio group, an n-propylthio group, an i-propylthio group, an n-butylthio group, an i-butylthio group, an s-butylthio group, or a t-butylthio group; C1-6 haloalkylthio groups, such as a trifluoromethylthio group or a 2,2,2-trifluoroethylthio group; C6 to C10 arylthio groups, such as a phenylthio group or a naphthylthio group; 5- to 6-membered heteroarylthio groups, such as a thiazolylthio group and a pyridylthio group;

[0023] C1 to C6 alkylsulfinyl groups, such as a methylsulfinyl group, an ethylsulfinyl group, or a t-butylsulfinyl group; C1-6 haloalkylsulfinyl groups such as a trifluoromethylsulfinyl group or a 2,2,2-trifluoroethylsulfinyl group; C6-10 arylsulfinyl groups such as a phenylsulfinyl group; 5- to 6-membered heteroarylsulfinyl groups such as thiazolylsulfinyl groups and pyridylsulfinyl groups;

[0024] C1 to C6 alkylsulfonyl groups, such as a methylsulfonyl group, an ethylsulfonyl group, or a t-butylsulfonyl group; C1-6 haloalkylsulfonyl groups, such as a trifluoromethylsulfonyl group or a 2,2,2-trifluoroethylsulfonyl group; C6-10 arylsulfonyl groups such as phenylsulfonyl groups; 5- to 6-membered heteroarylsulfonyl groups such as thiazolylsulfonyl groups and pyridylsulfonyl groups; Sulfo group; C1 to C6 alkylsulfonyloxy groups, such as a methylsulfonyloxy group, an ethylsulfonyloxy group, or a t-butylsulfonyloxy group; C1-6 haloalkylsulfonyloxy groups, such as a trifluoromethylsulfonyloxy group or a 2,2,2-trifluoroethylsulfonyloxy group;

[0025] Tri-C1-6 alkyl-substituted silyl groups, such as a trimethylsilyl group, a triethylsilyl group, or a t-butyldimethylsilyl group; Tri-C6-10 aryl-substituted silyl groups such as triphenylsilyl groups; C2-C6 alkenyl C1-C6 dialkyl-substituted silyl groups, such as an allyldimethylsilyl group and a vinyldimethylsilyl group; C1-C6 alkyldiC6-C10 aryl-substituted silyl groups such as t-butyldiphenylsilyl group and diphenylmethylsilyl group; Di-C1-C6 alkyl, C6-C10 aryl-substituted silyl groups such as dimethylphenylsilyl groups; (C6-C10 phenylC1-C6 alkyl)diC1-C6 alkylsilyl groups such as a benzyldimethylsilyl group and a 3-phenylpropyldimethylsilyl group; C1-C6 alkyl, C6-C10 phenyl, C2-C6 alkenylsilyl groups such as methylphenylvinylsilyl groups; Tri-C1 to C6 alkoxy-substituted silyl groups, such as a trimethoxysilyl group and a triethoxysilyl group; Di-C1 to C6 alkyl-substituted silyl groups such as a dimethylsilyl group and a diethylsilyl group; Di-C1 to C6 alkoxy-substituted silyl groups, such as dimethoxysilyl group and diethoxysilyl group; C1-C6 alkoxy C1-C6 alkyl-substituted silyl groups such as methoxydimethylsilyl group; C1-C6 alkoxy C6-C10 aryl-substituted silyl groups such as t-butoxydiphenylsilyl group; C1-C6 alkyldiC1-C6 alkoxy-substituted silyl groups such as methyldimethoxysilyl group; Cyano group; Nitro group.

[0026] In addition, any hydrogen atom in these "substituents" may be substituted with a group of a different structure. In this case, examples of the "substituent" include a C1-6 alkyl group, a C1-6 haloalkyl group, a C1-6 alkoxy group, a C1-6 haloalkoxy group, a halogeno group, a cyano group, and a nitro group.

[0027] The above "3- to 6-membered heterocyclyl group" includes 1 to 4 heteroatoms selected from the group consisting of nitrogen, oxygen, and sulfur atoms as ring-constituting atoms. The heterocyclyl group may be either a monocyclic or polycyclic ring. As for the polycyclic heterocyclyl group, as long as at least one ring is a heterocyclic ring, the remaining rings may be either a saturated alicyclic ring, an unsaturated alicyclic ring, or an aromatic ring. Examples of the "3- to 6-membered heterocyclyl group" include a 3- to 6-membered saturated heterocyclyl group, a 5- to 6-membered heteroaryl group, and a 5- to 6-membered partially unsaturated heterocyclyl group.

[0028] Examples of the 3- to 6-membered saturated heterocyclyl group include an aziridinyl group, an epoxy group, a pyrrolidinyl group, a tetrahydrofuranyl group, a thiazolidinyl group, a piperidyl group, a piperazinyl group, a morpholinyl group, a dioxolanyl group, and a dioxanyl group.

[0029] Examples of the 5-membered heteroaryl group include a pyrrolyl group, a furyl group, a thienyl group, an imidazolyl group, a pyrazolyl group, an oxazolyl group, an isoxazolyl group, a thiazolyl group, an isothiazolyl group, a triazolyl group, an oxadiazolyl group, a thiadiazolyl group, and a tetrazolyl group. Examples of the 6-membered heteroaryl group include a pyridyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, and a triazinyl group. Examples of the 5- to 6-membered partially unsaturated heterocyclyl group include an isoxazolinyl group and a pyrazolinyl group. Examples of the 3- to 6-membered heterocyclyl1-6 alkyl group include a glycidyl group, a 2-tetrahydrofuranylmethyl group, a 2-pyrrolylmethyl group, a 2-imidazolylmethyl group, a 3-isoxazolylmethyl group, a 5-isoxazolylmethyl group, a 2-pyridylmethyl group, a 4-pyridylmethyl group, and a 3-isoxazolinylmethyl group.

[0030] In X of formula (I), examples of the "cycloalkyl group" in the "unsubstituted or substituted cycloalkyl group" include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cubanyl group.

[0031] In X of formula (I), the "aryl group" of the "unsubstituted or substituted aryl group" may be either a monocyclic or polycyclic aryl group. As long as at least one ring of the polycyclic aryl group is an aromatic ring, the remaining rings may be any of a saturated alicyclic ring, an unsaturated alicyclic ring, or an aromatic ring. Examples of the aryl group include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, an azulenyl group, an indenyl group, an indanyl group, and a tetralinyl group.

[0032] In X of formula (I), examples of the "heterocyclyl group" of the "unsubstituted or substituted heterocyclyl group" include the same groups as those exemplified as the "3- to 6-membered heterocyclyl group" of the "substituent".

[0033] In the formula (I), X represents "-Si(R 1 )(R 2 )(R 3 )" R 1 ~R 3 each independently represents a hydrogen atom, an unsubstituted or substituted alkyl group, or an unsubstituted or substituted aryl group. The "alkyl group" in the "unsubstituted or substituted alkyl group" may be a straight chain or a branched chain, and examples of such groups include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an i-propyl group, an i-butyl group, an s-butyl group, an t-butyl group, an i-pentyl group, a neopentyl group, a 2-methyl-n-butyl group, and an i-hexyl group. The "aryl group" in the "unsubstituted or substituted aryl group" may be either a monocyclic or polycyclic aryl group. As long as at least one ring of the polycyclic aryl group is an aromatic ring, the remaining rings may be either a saturated alicyclic ring, an unsaturated alicyclic ring, or an aromatic ring. Examples of the polycyclic aryl group include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, an azulenyl group, an indenyl group, an indanyl group, and a tetralinyl group.

[0034] -Si(R 1 )(R 2 )(R 3 Examples of the "silane group" include a silane group, a trimethylsilyl group, a triethylsilyl group, a triisopropylsilyl group, a tri(n-butyl)silyl group, a t-butyldimethylsilyl group, a 3-cyanopropyldimethylsilyl group, a dimethyl(n-butyl)silyl group, a dimethyl(n-nonyl)silyl group, a dimethyl(n-undecanyl)silyl group, a diethylisopropylsilyl group, a dimethylisopropylsilyl group, a dimethyl(n-propyl)silyl group, a dimethyl(n-hexyl)silyl group, a dimethylstearylsilyl group, a dimethylethylsilyl group, a dimethyl(1,1,2-trimethylpropyl)silyl group, a triphenylsilyl group, a diphenylmethylsilyl group, a diphenyl(t-butyl)silyl group, a dimethyl(3-phenylpropyl)silyl group, a dimethylphenylsilyl group, a benzyldimethylsilyl group, a bromomethyldimethylsilyl group, a chloromethyldimethylsilyl group, a dimethylsilyl group, a diisopropylsilyl group, and a diphenylsilyl group.

[0035] In formula (I), Y is a single bond, an alkylene group, -O-, -S-, -S(O)-, -SO2-, -N(R 4 )- or a combination thereof. Examples of the alkylene group include a methylene group, an ethylene group, a 1,3-propylene group, a 1,2-propylene group, a 2,2-propylene group, a 1,4-butylene group, a 1,3-butylene group, and a 1,2-butylene group.

[0036] R 4 represents a hydrogen atom, an unsubstituted or substituted alkyl group, an unsubstituted or substituted cycloalkyl group, an unsubstituted or substituted arylalkyl group, an unsubstituted or substituted aryl group, or an unsubstituted or substituted heterocyclyl group. The alkyl group is R 1Examples of the cycloalkyl group, aryl group, and heterocyclyl group include the same as those listed for X, and examples of the arylalkyl group include a benzyl group, a phenethyl group, and a 3-phenylpropyl group.

[0037] In formula (I), Y is a single bond, an alkylene group, -O-, -S-, -S(O)-, -SO2-, or -N(R 4 The group combining -Y and -X is not particularly limited in terms of the combination or number of combinations, and can be freely combined as long as it is within a chemically permissible range. Examples of such combined groups include -NHO-, -CHO-, -CHCHO-, -CHS-, -CHCHS-, -OCHCHO-, -SCHCHS-, -OCHCHS-, -CHOCHCHO-, -SONNH-, -SON(CH)-, etc. The position at which the phenyl group and X are bonded can be selected arbitrarily within a chemically permissible range. That is, when Y is -CHO-, any of the following cases is included.

[0038] [ka]

[0039] Examples of the carboxylate ion represented by formula (I) include the compounds shown below.

[0040] [ka]

[0041] [ka]

[0042] [ka]

[0043] [ka]

[0044] [ka]

[0045] The metal organic framework of the present invention can contain an organic ligand other than the organic ligand represented by formula (I). Specific examples of such organic ligands include terephthalic acid, phthalic acid, isophthalic acid, 5-cyanoisophthalic acid, 1,3,5-trimesic acid, 1,3,5-tris(4-carboxyphenyl)benzene, 4,4'-dicarboxybiphenyl, 3,5-dicarboxypyridine, 2,3-dicarboxypyrazine, 1,3,5-tris(4-carboxyphenyl)benzene, 1,2,4,5-tetrakis(4-carboxyphenyl)benzene, 9,10-anthracenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, [1,1':4',1"]terphenyl-3,3",5,5"-tetracarboxylic acid, biphenyl-3,3',5,5'-tetracarboxylic acid, 3,3',5,5'-tetracarboxamide, ... Examples of the carboxylic acid include carboxydiphenylmethane, 1,3,5-tris(4'-carboxy[1,1'-biphenyl]-4-yl)benzene, 1,3,5-tris(4-carboxyphenyl)triazine, 1,2-bis(4-carboxy-3-nitrophenyl)ethene, 1,2-bis(4-carboxy-3-aminophenyl)ethene, trans,trans-muconic acid, fumaric acid, benzimidazole, imidazole, 1,4-diazabicyclo[2.2.2]octane (DABCO), pyrazine, 4,4'-dipyridyl, 1,2-di(4-pyridyl)ethylene, 2,7-diazapyrene, 4,4'-azobispyridine, and copper bis(3-(4-pyridyl)-2,4-pentanedionato).

[0046] When an organic ligand represented by formula (I) and an organic ligand other than formula (I) are mixed and used, the mixing molar ratio is not particularly limited. For example, in the case of a pillar molecule for constructing a three-dimensional structure such as a pillared layer type structure by crosslinking with a pillar molecule, it is preferable to use an excess of the organic ligand other than formula (I) relative to the organic ligand represented by formula (I).

[0047] The method for producing the metal organic framework of the present invention is not particularly limited, and any of the following methods can be used: solution methods such as a solvent diffusion method, a solvent stirring method, and a hydrothermal method; a microwave method in which a reaction solution is irradiated with microwaves to uniformly heat the entire system in a short time; an ultrasonic method in which pressure changes repeatedly occur in a reaction vessel by irradiating a reaction vessel with ultrasound, and this pressure change causes a phenomenon called cavitation in which the solvent forms bubbles and collapses, and at that time, a high-energy field of about 5000 K and 10000 bar is locally formed as a reaction field for each generation of crystals; a solid-phase synthesis method in which a metal ion source and an organic ligand are mixed without using a solvent; and a LAG (liquid assisted grinding) method in which water about the amount of crystal water is added to mix the metal ion source and the organic ligand.

[0048] For example, the method includes steps of preparing a first solution containing a metal compound serving as a source of metal ions and a solvent, a second solution containing a carboxylic acid that is a precursor of the organic ligand represented by formula (I) and a solvent, and a third solution containing a compound that will become another multidentate ligand and a solvent, as necessary, and a step of mixing the first solution, the second solution, and the third solution to prepare a reaction liquid, and heating the reaction liquid to obtain a metal organic framework. The first to third solutions do not need to be prepared separately, and for example, the metal compound, the carboxylic acid that is a precursor of the organic ligand represented by formula (I), the compound that will become another multidentate ligand, and the solvent may be mixed at once to prepare one solution.

[0049] The mixing molar ratio of the metal compound and the organic ligand represented by formula (I) can be arbitrarily selected depending on the pore size and surface properties of the resulting metal organic framework, but it is preferable to use 1 mole or more of the metal compound per mole of the organic ligand represented by formula (I), and more preferably 1.1 moles or more, more preferably 1.2 moles or more, more preferably 1.5 moles or more, more preferably 2 moles or more, and even more preferably 3 moles or more. The concentration of the metal ions in the reaction solution is preferably in the range of 25 to 200 mmol / L.

[0050] The concentration of the organic ligand represented by formula (1) in the reaction solution is preferably in the range of 10 to 100 mmol / L. The concentration of the organic ligand other than the formula (I) in the reaction solution is preferably 25 to 100 mmol / L.

[0051] The solvent used may be one or more selected from the group consisting of N,N-dimethylformamide (hereinafter sometimes referred to as "DMF"), N,N-diethylformamide (hereinafter sometimes referred to as "DEF"), N,N-dimethylacetamide and water. Among these, it is preferable to use either N,N-dimethylformamide, N,N-diethylformamide or dimethylacetamide alone, or to use a mixed solvent of N,N-dimethylformamide / water, a mixed solvent of N,N-diethylformamide / water or a mixed solvent of N,N-dimethylacetamide / water.

[0052] The heating temperature of the reaction solution is not particularly limited, but is preferably within the range of room temperature to 140°C.

[0053] The MOF of the present invention is a porous coordination polymer, and by utilizing the large surface area of ​​its pores, it can be used for gas storage, gas separation, or as a heterogeneous catalyst, among which it is particularly suitable for gas storage. There are no particular limitations on the gas that can be stored, and by appropriately adjusting the size of the pores, hydrogen, nitrogen, carbon dioxide, and lower hydrocarbons can be stored.

[0054] The method for storing gas using the MOF of the present invention is not particularly limited, but a method of contacting the MOF of the present invention with a gas is preferred, and the contact method is not particularly limited. For example, a method of filling a tank with the MOF of the present invention and flowing a gas into the tank, a method of supporting the MOF of the present invention on the surface constituting the inner wall of a tank and flowing a gas into the tank, a method of forming a tank from a material containing MOF and flowing a gas into the tank, etc. can be mentioned. EXAMPLES

[0055] The present invention will be described in detail below using examples, but the scope of the present invention is not limited to the examples.

[0056] Table 1 shows the structures of the carboxylic acids that serve as precursors of organic ligands 1 to 31 represented by formula (I) used in the examples (hereinafter, the precursor carboxylic acids are collectively referred to as "organic ligands"). The symbols in Table 1 have the following meanings. Me: methyl group, Ph: phenyl group, Py: pyridyl group, c-Pr: cyclopropyl group, c-Hex: cyclohexyl group, O: oxygen atom, N: nitrogen atom, S: sulfur atom, Cl: chlorine atom, F: fluorine atom, H: hydrogen atom, C: carbon atom. The numbers in XY- in Table 1 represent the substitution positions. For example, 2-MePh represents a 2-methylphenyl group in which a methyl group is substituted at the 2-position, with the 1-position being the position where the phenyl group is bonded to the benzene ring in formula (I).

[0057] [Table 1]

[0058] [Production Example 1] Synthesis of organic ligand 1 Diethyl 2,5-dibromoterephthalate (5.0 mmol), o-methylphenylboronic acid (12.5 mmol), tetrakis(triphenylphosphine)palladium (0.05 mmol), 10 mL of 2M aqueous sodium carbonate, 35 mL of toluene, and 10 mL of ethanol were heated at 90°C under nitrogen for 36 hours. The mixture was returned to room temperature, water was added, and the organic layer was dried over magnesium sulfate and filtered. The filtrate was distilled under reduced pressure, and the obtained solid was purified using silica gel column chromatography (chloroform). 1.5 g (3.7 mmol) of diethyl 2,5-di(o-methylphenyl)terephthalate was obtained as a yellow solid. Potassium hydroxide (100 mmol), 50 mL of ethanol, and 40 mL of water were added to the obtained yellow solid, and the mixture was heated at 100°C for 2 hours. The mixture was returned to room temperature, and concentrated hydrochloric acid was added. The mixture was extracted with ethyl acetate, dried over magnesium sulfate, and filtered. The filtrate was evaporated under reduced pressure to obtain 1.2 g (3.46 mmol) of organic ligand 1.

[0059] [Production Example 2] Synthesis of organic ligand 2 Organic ligand 2 was obtained in the same manner as in Production Example 1, except that m-methylphenylboronic acid was used instead of o-methylphenylboronic acid.

[0060] [Production Example 3] Synthesis of organic ligand 4 Diethyl 2,5-dibromoterephthalate (5.0 mmol), 2,6-dimethylphenylboronic acid (12.5 mmol), tris(dibenzylideneacetone)dipalladium (0.25 mmol), 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (1.0 mmol), potassium phosphate (15 mmol), and 50 mL of toluene were refluxed under nitrogen for two days. The mixture was returned to room temperature, filtered through Celite, and the filtrate was distilled under reduced pressure. The solid obtained was purified using silica gel column chromatography (chloroform). The solid was washed with hexane and dried to obtain 2.1 mmol of diethyl 2,5-bis(2,6-dimethylphenyl)terephthalate as a colorless solid. Potassium hydroxide (40 mmol), 50 mL of ethanol, and 20 mL of water were added to the solid obtained, and the mixture was heated at 100°C for 15 hours. The mixture was returned to room temperature, and concentrated hydrochloric acid was added. The mixture was extracted with ethyl acetate, dried over magnesium sulfate, and filtered. The filtrate was evaporated under reduced pressure to obtain 0.8 g (2.1 mmol) of organic ligand 4.

[0061] [Production Example 4] Synthesis of organic ligand 5 Organic ligand 5 was obtained in the same manner as in Production Example 1, except that o-chlorophenylboronic acid was used instead of o-methylphenylboronic acid.

[0062] [Production Example 5] Synthesis of organic ligand 6 Organic ligand 6 was obtained in the same manner as in Production Example 1, except that m-chlorophenylboronic acid was used instead of o-methylphenylboronic acid.

[0063] [Production Example 6] Synthesis of organic ligand 7 Diethyl 2,5-dibromoterephthalate (5.0 mmol), o-trifluoromethylphenylboronic acid (12.0 mmol), [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) dichloride dichloromethane adduct (0.25 mmol), potassium phosphate (20 mmol), and 20 mL of dimethoxyethane were refluxed under nitrogen for one day. The mixture was returned to room temperature, washed with water, extracted with ethyl acetate, and then dried over magnesium sulfate. After filtration, the filtrate was distilled under reduced pressure, and the obtained solid was purified using silica gel column chromatography (chloroform). The solid was washed with hexane and dried to obtain 2.2 mmol of diethyl 2,5-bis(o-trifluoromethylphenyl)terephthalate as a colorless solid. Potassium hydroxide (40 mmol), 50 mL of ethanol, and 20 mL of water were added to the obtained solid, and the mixture was heated at 100°C for 15 hours. The mixture was returned to room temperature, and concentrated hydrochloric acid was added. The mixture was extracted with ethyl acetate, dried over magnesium sulfate, and filtered. The filtrate was evaporated under reduced pressure to obtain 0.8 g (1.9 mmol) of organic ligand 7.

[0064] [Production Example 7] Synthesis of organic ligand 8 Organic ligand 8 was obtained in the same manner as in Production Example 6, except that m-trifluoromethylphenylboronic acid was used instead of o-trifluoromethylphenylboronic acid.

[0065] [Production Example 8] Synthesis of organic ligand 9 Organic ligand 9 was obtained in the same manner as in Production Example 6, except that p-trifluoromethylphenylboronic acid was used instead of o-trifluoromethylphenylboronic acid.

[0066] [Production Example 9] Synthesis of organic ligand 10 2,5-Dibromo-p-xylene (5.0mmol), 3-pyridylboronic acid (12.0mmol), tetrakis(triphenylphosphine)palladium (0.5mmol), sodium hydroxide (20mmol), toluene 20mL, ethanol 15mL, and water 10mL were refluxed under nitrogen for one day. The mixture was returned to room temperature, washed with water, extracted with ethyl acetate, and then dried over magnesium sulfate. After filtration, the filtrate was distilled under reduced pressure, and the obtained solid was purified using silica gel column chromatography (ethyl acetate → chloroform:methanol = 9:1). 3.4mmol of 2,5-di(3-pyridyl)-p-xylene was obtained as a colorless solid. Potassium permanganate (20mmol) and water 15mL were added to the obtained solid, and the mixture was heated overnight. The mixture was returned to room temperature, filtered, and the residue was thoroughly washed with hot water. Hydrochloric acid was added to the filtrate to adjust the pH to 3. The filtrate was distilled off under reduced pressure, and the resulting solid was thoroughly washed with water and dried to obtain 0.3 g (0.6 mmol) of organic ligand 10.

[0067] [Production Example 10] Synthesis of organic ligand 11 2,5-Dibromoterephthalic acid (10.0mmol), 4-hydroxypyridine (40mmol), copper powder (3.0mmol), copper iodide (0.8mmol), 100mL of dimethylformamide, diazabicycloundecene (60.0mmol), and 0.2mL of pyridine were added and heated under reflux overnight. The mixture was returned to room temperature, hydrochloric acid was added, and the precipitated solid was filtered, and the residue was thoroughly washed with water. The mixture was dried to obtain 3.0g (6.0mmol) of organic ligand 11 as a white solid.

[0068] [Production Example 11] Synthesis of organic ligand 12 Diethyl 2,5-dibromoterephthalate (5.0mmol), cyclopropylboronic acid (12.0mmol), palladium acetate (0.05mmol), potassium phosphate (16mmol), tricyclohexylphosphine (1.0mmol), toluene 20mL, and water 1mL were heated at 100℃ overnight under nitrogen. Water was added and extracted with ethyl acetate, and the organic layer was dried over magnesium sulfate and filtered. The filtrate was distilled under reduced pressure, and the obtained solid was purified using silica gel column chromatography (chloroform). Diethyl 2,5-dicyclopropylterephthalate was obtained as a colorless solid. Potassium hydroxide (50mmol), ethanol 50mL, and water 20mL were added to the obtained colorless solid, and the mixture was heated at 100℃ for 2 hours. The mixture was returned to room temperature, and concentrated hydrochloric acid was added. The mixture was extracted with ethyl acetate, dried over magnesium sulfate, and filtered. The filtrate was distilled under reduced pressure to obtain 1.7g (4.2mmol) of organic ligand 12.

[0069] [Production Example 12] Synthesis of organic ligand 13 Iodine (3.0 mmol) was added to p-di(cyclohexyl)benzene (30 mmol) and dissolved in chloroform. Bromine (60 mmol) was added dropwise and stirred for 48 hours. 20% sodium hydroxide was added and extracted with diethyl ether. The extracted solution was dried over magnesium sulfate, filtered, and the filtrate was distilled under reduced pressure to obtain 2,5-dibromo-1,4-dicyclohexylbenzene (27 mmol). Copper cyanide (30 mmol) was added to the obtained dibromo product (10 mmol) and dissolved in 30 mL of dimethylformamide. The mixture was refluxed overnight and returned to room temperature, and then 100 mL of aqueous ammonia was added. The precipitated solid was filtered, washed thoroughly with water, and dissolved in chloroform. After drying over magnesium sulfate, the mixture was filtered, and the filtrate was distilled under reduced pressure. The resulting crude product was recrystallized with hexane to obtain 2,5-dicyano-1,4-dicyclohexylbenzene (9.5 mmol) as a colorless solid. 75 mmol of 10 M aqueous sodium hydroxide was added to the resulting dicyano compound (5.0 mmol), and the mixture was dissolved in 50 mL of ethylene glycol and refluxed overnight. After returning to room temperature, 100 mL of water was added, and the pH was adjusted to pH 1 by adding hydrochloric acid. The precipitated solid was filtered and thoroughly dried to obtain 2.2 g (4.6 mmol) of organic ligand 13.

[0070] [Production Example 13] Synthesis of organic ligand 15 Organic ligand 15 was obtained in the same manner as in Production Example 10, except that m-cresol was used instead of 4-hydroxypyridine.

[0071] [Production Example 14] Synthesis of organic ligand 16 Organic ligand 16 was obtained in the same manner as in Production Example 10, except that o-cresol was used instead of 4-hydroxypyridine.

[0072] [Production Example 15] Synthesis of organic ligand 17 Organic ligand 17 was obtained in the same manner as in Production Example 10, except that p-cresol was used instead of 4-hydroxypyridine.

[0073] [Production Example 16] Synthesis of organic ligand 18 Organic ligand 18 was obtained in the same manner as in Production Example 10, except that p-chlorophenol was used instead of 4-hydroxypyridine.

[0074] [Production Example 17] Synthesis of organic ligand 21 Organic ligand 21 was obtained in the same manner as in Preparation Example 10, except that 2-naphthol was used instead of 4-hydroxypyridine.

[0075] [Production Example 18] Synthesis of organic ligand 22 Organic ligand 22 was obtained in the same manner as in Preparation Example 10, except that 4-methoxyphenol was used instead of 4-hydroxypyridine.

[0076] [Production Example 19] Synthesis of organic ligand 23 Organic ligand 23 was obtained in the same manner as in Production Example 1, except that 3-thienylboronic acid was used instead of o-methylphenylboronic acid.

[0077] [Production Example 20] Synthesis of organic ligand 24 Organic ligand 24 was obtained in the same manner as in Production Example 1, except that p-chlorophenylboronic acid was used instead of o-methylphenylboronic acid.

[0078] [Production Example 21] Synthesis of organic ligand 25 Organic ligand 25 was obtained in the same manner as in Production Example 1, except that p-methoxyphenylboronic acid was used instead of o-methylphenylboronic acid.

[0079] [Production Example 22] Synthesis of organic ligand 26 Organic ligand 26 was obtained in the same manner as in Production Example 1, except that m-methoxyphenylboronic acid was used instead of o-methylphenylboronic acid.

[0080] [Production Example 23] Synthesis of organic ligand 27 Organic ligand 27 was obtained in the same manner as in Production Example 1, except that o-methoxyphenylboronic acid was used instead of o-methylphenylboronic acid.

[0081] [Production Example 24] Synthesis of organic ligand 28 Organic ligand 28 was obtained in the same manner as in Production Example 1, except that 3-furylboronic acid was used instead of o-methylphenylboronic acid.

[0082] [Production Example 25] Synthesis of organic ligand 29 Organic ligand 29 was obtained in the same manner as in Production Example 1, except that o-methylthiophenylboronic acid was used instead of o-methylphenylboronic acid.

[0083] [Production Example 26] Synthesis of organic ligand 30 Organic ligand 30 was obtained in the same manner as in Production Example 1, except that m-methylthiophenylboronic acid was used instead of o-methylphenylboronic acid.

[0084] [Production Example 27] Synthesis of organic ligand 31 Organic ligand 31 was obtained in the same manner as in Production Example 1, except that p-methylthiophenylboronic acid was used instead of o-methylphenylboronic acid.

[0085] [Comparative Example 1] 166.7 mg of terephthalic acid was dissolved in 13 mL of DMF, and 0.28 mL of triethylamine was added thereto. 17 mL of a DMF solution containing 557.7 mg of zinc acetate dihydrate was added dropwise thereto. The mixture was stirred at room temperature for 2.5 hours, and the resulting solid was separated by centrifugation. The supernatant was removed, and the solid was immersed in 20 mL of DMF overnight. The mixture was then centrifuged to remove the supernatant, and replaced with chloroform. The centrifuged solid was immersed in 20 mL of chloroform overnight, and centrifuged again, and this operation was repeated three times. The centrifuged solid was then vacuum-dried at 150°C for 5 hours to obtain 142.9 mg of metal-organic framework A as a white powder.

[0086] [Comparative Example 2] 50 mL of DMF was added to 0.492 g of 2,5-dimethylterephthalic acid and 1.49 g of zinc nitrate hexahydrate, and the mixture was heated in an oven (reaction conditions: 120°C, 24 hours). The mixture was returned to room temperature, and the supernatant was removed. 50 mL of DMF was added, the supernatant was removed, and the solvent was exchanged with chloroform. 50 mL of chloroform was added, and the mixture was immersed overnight. The solid was filtered by suction, and the obtained solid was vacuum dried at 150°C for 5 hours, to obtain 0.709 g of metal-organic structure B.

[0087] [Example 1-1] Organic ligand 1 (0.375 mmol), zinc nitrate hexahydrate (0.375 mmol), 1,4-diazabicyclo[2.2.2]octane (0.20 mmol), and 7.5 mL of DMF were stirred at room temperature for 15 minutes while applying ultrasonic waves. After that, the filtrate was centrifuged and filtered, and placed in an autoclave and heated in an oven (reaction conditions: 120 ° C, 66 hours). After returning to room temperature and discarding the supernatant, the crystals were washed with DMF. The crystals were then immersed in DMF overnight. The supernatant was then removed and replaced with chloroform, and the crystals were then immersed for a day. The process of centrifuging and then removing the supernatant was repeated three times. The solid obtained by centrifuging and removing the supernatant was vacuum dried at 150 ° C to obtain metal organic framework 1-1 as a white powder.

[0088] [Examples 1-2] to [Examples 1-24] Metal organic frameworks 1-2 to 1-24 were obtained by the same operation as in Example 1-1, except that the organic ligands and solvents shown in the following Table 2 were used and the reaction was carried out under the reaction conditions shown in Table 2. The results are shown in Table 2.

[0089] [Table 2]

[0090] [Example 2-1] Organic ligand 20 (0.5 mmol) was dissolved in 7 mL of DMF. A solution of zinc acetate dihydrate (1.27 mmol) in 8 mL of DMF was added dropwise thereto. The mixture was stirred at room temperature for 2.5 hours, and the obtained solid was separated by centrifugation. The supernatant was removed, and the solid was immersed in 20 mL of DMF overnight. The supernatant was then removed by centrifugation and replaced with chloroform. The centrifuged solid was immersed in 20 mL of chloroform overnight and centrifuged again, and this washing operation was repeated three times. The centrifuged solid was then vacuum-dried at 150°C for 5 hours to obtain metal-organic framework 2-1 as a white powder.

[0091] [Example 2-2] to [Example 2-15] Metal organic frameworks 2-2 to 2-15 were obtained by the same operation as in Example 2-1, except that the organic ligands and solvents shown in the following Table 3 were used and the reaction was carried out under the reaction conditions shown in Table 3. The results are shown in Table 3.

[0092] [Table 3]

[0093] [Example 3-1] Organic ligand 20 (1.0 mmol) was dissolved in 13 mL of DMF, and triethylamine (0.0038 mmol) was added thereto. A solution of zinc acetate dihydrate (2.5 mmol) in 17 mL of DMF was added dropwise thereto. The mixture was stirred at room temperature for 2.5 hours, and the obtained solid was separated by centrifugation. The supernatant was removed, and the solid was immersed in 20 mL of DMF overnight. The supernatant was then removed by centrifugation, and replaced with chloroform. The centrifuged solid was immersed in 20 mL of chloroform overnight, and centrifuged again, and this washing operation was repeated three times. The centrifuged solid was then vacuum-dried at 150°C for 5 hours to obtain metal-organic framework 3-1 as a white powder.

[0094] [Example 3-2] to [Example 3-12] Metal organic frameworks 3-2 to 3-12 were obtained by the same operation as in Example 3-1, except that the organic ligands and solvents shown in the following Table 4 were used and the reaction was performed under the reaction conditions shown in Table 4. The results are shown in Table 4.

[0095] [Table 4]

[0096] [Example 4-1] 10 mL of DMF was added to organic ligand 14 (0.3 mmol) and zinc nitrate hexahydrate (0.4 mmol), and the mixture was stirred for 5 minutes. Triethylamine (0.0068 mmol) was added dropwise thereto, and the mixture was stirred at room temperature for 5 minutes. After standing for 20 minutes, the mixture was centrifuged for 10 minutes, and the supernatant was removed. 10 mL of DMF was added to the residue, and the mixture was centrifuged again for 10 minutes, and the supernatant was removed. After immersion in DMF overnight, the mixture was centrifuged for 10 minutes, and after removing the supernatant, 10 mL of chloroform was added. The centrifuged solid was immersed in 20 mL of chloroform overnight, and the washing operation of centrifuging again was repeated three times. After that, the centrifuged solid was vacuum dried at 150 ° C for 5 hours to obtain metal organic framework 4-1 as a pale yellow powder.

[0097] [Example 4-2] to [Example 4-20] Metal organic frameworks 4-2 to 4-20 were obtained by the same operation as in Example 4-1, except that the organic ligands shown in Table 5 below were used. The results are shown in Table 5.

[0098] [Table 5]

[0099] [Example 5-1] 3.8 mL of DMF was added to organic ligand 14 (0.175 mmol) and zinc nitrate hexahydrate (0.352 mmol), and the mixture was heated in an oven (reaction conditions: 100°C, 161 hours). The mixture was returned to room temperature, centrifuged, and the supernatant was removed. 10 mL of DMF was added, and the mixture was centrifuged to remove the solvent, which was then exchanged for chloroform. 10 mL of chloroform was added, and the mixture was immersed overnight. After removing the chloroform by centrifugation, the mixture was vacuum dried at 150°C for 5 hours, and metal-organic framework 5-1 was obtained as pale orange crystals.

[0100] [Example 5-2] to [Example 5-86] Metal organic frameworks 5-2 to 5-86 were obtained by the same operation as in Example 5-1, except that the organic ligands and solvents shown in Table 6 below were used and the reactions were carried out under the reaction conditions shown in Table 6. The results are shown in Table 6.

[0101] [Table 6]

[0102] TIFF0007621252000015.tif242170

[0103] TIFF0007621252000016.tif40170

[0104] [Example 6-1] 3 mL of a DMF solution of organic ligand 12 (0.38 mmol) and 2.5 mL of a DMF solution of 1,4-diazabicyclo[2.2.2]octane (0.2 mmol) were slowly dropped into a 2 mL DMF solution of zinc acetate dihydrate (0.38 mmol). After stirring at room temperature for 2.5 hours, centrifugation was performed and the supernatant was removed. DMF was added and the mixture was immersed overnight, after which the supernatant was removed and replaced with chloroform, 10 mL of chloroform was added and the mixture was immersed for one day. The process of centrifuging, removing the solvent, adding chloroform again, immersing overnight, centrifuging and removing the supernatant was repeated three times. The solid obtained by centrifugation and removing the supernatant was vacuum dried at 150 ° C to obtain metal organic framework 6-1 as colorless crystals.

[0105] [Example 7-1] 0.152 g of organic ligand 25 and 0.233 g of nickel nitrate hexahydrate were added with 9 mL of THF and 1 mL of water, and heated in an oven (reaction conditions: 100°C, 48 hours). The mixture was returned to room temperature, centrifuged, and then decanted to obtain a solid. DMF was added to the solid, and the operation of centrifuging and decanting was repeated three times, and DMF was added and the mixture was soaked overnight. The supernatant was removed, and chloroform was added to the solid, and the operation of centrifuging and decanting was repeated three times, the solvent was exchanged with chloroform, and chloroform was added and the mixture was soaked overnight. The solid obtained by decantation was vacuum dried at 150°C for 5 hours, and 0.178 g of metal organic framework 7-1 was obtained.

[0106] [Example 7-2] to [Example 7-17] Metal organic frameworks 7-2 to 7-17 were obtained by using the organic ligands shown in Table 7 below and carrying out the same operation as in Example 7-1 except for the reaction conditions shown in Table 7. The results are shown in Table 7.

[0107] [Table 7]

[0108] [Example 8-1] 0.114 g of organic ligand 25, 0.0702 g of zirconium chloride, 0.0625 g of water, 0.5406 g of acetic acid, and 4 mL of DMF were stirred at room temperature for 5 minutes while applying ultrasonic waves. Then, the mixture was heated in an oven (reaction conditions: 120°C, 24 hours). The mixture was returned to room temperature, centrifuged, and decanted to obtain a solid. The operation of adding DMF to the solid, centrifuging, and decanting was repeated three times. The supernatant was removed, DMF was added, and the mixture was soaked overnight. After centrifugation and decantation, the operation of adding acetone to the obtained solid, centrifuging, and decanting was repeated three times. The supernatant was removed, acetone was added, and the mixture was soaked overnight. After centrifugation and decantation, the obtained solid was vacuum dried at 150°C for 5 hours to obtain 0.0826 g of metal organic framework 8-1.

[0109] [Example 8-2] to [Example 8-10] Metal organic frameworks 8-2 to 8-10 were obtained by the same operation as in Example 8-1, except that the organic ligands shown in Table 8 below were used. The results are shown in Table 8.

[0110] [Table 8]

[0111] [Example 9-1] 0.0759 g of organic ligand 25, 0.0484 g of copper nitrate trihydrate, and 4 mL of DMF were added, stirred, and then filtered. Then, the mixture was heated in an oven (reaction conditions: 120°C, 24 hours). The mixture was returned to room temperature, centrifuged, and decanted to obtain a solid. The operation of adding DMF to the solid, centrifuging, and decanting was repeated three times, and DMF was added and the mixture was soaked overnight. The supernatant was removed, and the solvent was exchanged with chloroform. The operation of adding chloroform, washing, and filtering under pressure was repeated three times, and chloroform was added and the mixture was soaked overnight. The solid was filtered under pressure, and the obtained solid was vacuum dried at 150°C for 5 hours to obtain 0.0670 g of metal-organic framework 9-1.

[0112] [Example 9-2] to [Example 9-32] Metal organic frameworks 9-2 to 9-32 were obtained by the same operation as in Example 9-1, except that the organic ligands shown in Table 9 below were used. The results are shown in Table 9.

[0113] [Table 9]

[0114] [Examples 10-1 and 10-2] 0.1839 g of organic ligand 11, 0.0521 g of copper acetate monohydrate, 0.1098 g of acetic acid, and 10 mL of DMF were added to a vial and ultrasonicated for 5 minutes. After that, it was heated in an oven (reaction conditions: 70°C, 7 days). When it was returned to room temperature, light blue and white solids were obtained. Each was visually separated, centrifuged, and decanted to obtain solids. DMF was added to each solid and immersed overnight. DMF was removed by centrifugation and decantation, and the solvent was exchanged with chloroform. This process was repeated three times for the blue solid, and the obtained solid was vacuum dried at 150°C for 5 hours, to obtain 0.0538 g of metal organic framework 10-1. The white solid was centrifuged and filtered under pressure three times, and then the obtained solid was vacuum dried at 150°C for 5 hours to obtain 0.0258 g of metal organic framework 10-2.

[0115] (BET specific surface area measurement and hydrogen storage capacity measurement) For a part of the obtained metal-organic framework, the BET specific surface area and the hydrogen storage capacity at 77 K and atmospheric pressure were measured. In addition, for a part of the metal-organic framework, the hydrogen storage capacity at 298 K and 10 MPa was measured. The BET specific surface area and the hydrogen storage capacity at 77K under atmospheric pressure were measured using a gas adsorption measurement device Tristar-II (Micromeritics).

[0116] The BET specific surface area was calculated by the following method. Approximately 50 mg of the metal-organic framework was placed inside a glass cell. The inside of the glass cell was depressurized to a vacuum at a temperature of 135°C and dried for 6 hours. The glass cell was attached to a gas adsorption measurement device and immersed in a thermostatic bath containing liquid nitrogen. The pressure of the nitrogen contained in the glass cell was gradually increased. When the pressure of the nitrogen introduced into the glass cell reached 1.0×10 5 The measurement was continued until the pressure reached 1 Pa.

[0117] The amount of hydrogen stored at 77K and normal pressure was calculated as follows. After measuring nitrogen, the gas type was changed to hydrogen and measurements were performed. The pressure of hydrogen contained in the glass cell was gradually increased. When the pressure of hydrogen introduced into the glass cell was 1.0×105 The measurement was continued until the pressure reached 1 Pa. The measured BET specific surface areas are shown in Table 10. The measured hydrogen storage capacity at 77K under atmospheric pressure is shown in Table 11.

[0118] [Table 10]

[0119] [Table 11] [Industrial Applicability]

[0120] The metal organic framework of the present invention can store gases such as hydrogen and nitrogen at a practical level, making it easier to use hydrogen as we move towards a hydrogen society.

Claims

1. A metal-organic framework hydrogen storage material comprising a carboxylate ion represented by formula (I) and a polyvalent metal ion bonded thereto, wherein the polyvalent metal ion is an ion of at least one metal selected from Zn, Fe, Co, Ni, Cu, Al, Zr, and Mg. 【Chemistry 1】 (In formula (I), X is, an unsubstituted or substituted cycloalkyl group; an unsubstituted or substituted aryl group; an unsubstituted or substituted furyl group, a thienyl group, or a pyridyl group; Or -Si(R １ ) (R ２ ) (R ３ ) represents the substituent is at least one selected from a C1-6 alkyl group, a C1-6 alkoxy group, a halogeno group, a C1-6 haloalkyl group, and a C1-6 alkylthio group; R １ ~R ３ are each independently Hydrogen atoms, Unsubstituted or substituted alkyl groups, or an unsubstituted or substituted aryl group, Y is, Single bond, An alkylene group, -O-, -S-, -S(O)-, or -SO ２ Represents -. however, X-Y- includes a phenyl group, a benzyloxy group, a pyrazol-1-yl group, and a group represented by formula (II) except for the cases where m is 3, 6, 8, 9, 10, 11, and 12. 【Chemistry 2】

2. The metal-organic framework hydrogen storage material according to claim 1, further comprising an organic ligand other than the organic ligand represented by formula (I) as a constituent component.

3. A hydrogen gas storage method comprising the steps of: bringing hydrogen gas into contact with the metal-organic framework hydrogen storage material according to claim 1 or 2; and adsorbing the hydrogen gas inside the metal-organic framework hydrogen storage material.

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