Gas storage material containing a metal-organic structure bonded by hydroxamic acid

Abstract

The object of the present invention is to provide a storage material for gases other than nitrogen that contains an MOF with a hydroxamic acid group as the binding site. [Solution] A gas storage material containing a metal-organic structure formed by bonding at least one polyvalent metal ion selected from Zn, Co, Ni, Cu, Zr, and Mg with at least one compound selected from those represented by the following formulas (1) to (2), wherein the gas is hydrogen or carbon dioxide. [Formula 1] JPEG2026074203000028.jpg34149

Description

[Technical Field]

[0001] The present invention relates to a novel storage material for gases other than nitrogen containing a metal-organic structure bonded by hydroxamic acid, a method for storing gases other than nitrogen using such storage material, and a storage tank for gases other than nitrogen. This application claims priority to Japanese Patent Application No. 2019-223660, filed on 11 December 2019, and Japanese Patent Application No. 2020-030761, filed on 26 February 2020, the contents of which are incorporated herein by reference. [Background technology]

[0002] Metal-organic structures (hereinafter sometimes referred to as "MOFs") are solid materials having a polymeric structure with internal spaces (i.e., pores) formed by combining metal ions with cross-linking organic ligands that connect them. They have attracted considerable interest over the past decade or so as porous materials with functions such as gas storage and separation. Much research has been conducted using terephthalic acid as an organic ligand, and it is known that MOF-5 obtained by a solvothermal method using Zn(NO3)2·6H2O in DMF with terephthalic acid as a cross-linking organic ligand can store 7.1% by mass of hydrogen relative to MOF-5 under conditions of 77K and 4MPa (see Patent Document 1 and Non-Patent Documents 1-3).

[0003] On the other hand, hydroxamic acids (-CONHOH), like carboxylic acids (-COOH), are known to coordinate strongly to metals. However, only two examples of metal-organic structures using 1,4-benzene-dicarbohydroxamic acid, obtained by replacing the carboxylic acid moiety of terephthalic acid with hydroxamic acid, as a ligand have been reported to date.

[0004] It has been reported that when UiO-66, an MOF obtained by a solvothermal method using zirconium tetrachloride in DMF with terephthalic acid as an organic ligand, and 1,4-benzene-dicarbohydroxamic acid (H2BDHA) are heated in DMF, the terephthalate forming UiO-66 is replaced by 1,4-benzene-dicarbohydroxamic acid, resulting in UiO-66-H2BDHA (Non-Patent Literature 4).

[0005] It has been reported that MUV-11, an MOF containing a hydroxamic acid moiety, can be obtained by a solvothermal method in which 1,4-benzene-dicarbohydroxamic acid is heated at 120°C in DMF together with tetraisopropyl orthotitanate and acetic acid (Non-Patent Literature 5). [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] U.S. Patent Application 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] C. Pereira, A. Howarth, N. Vermeulen, F. Almeida Paz, J. Tome, J. Hupp, O. Farha, Mater. Chem. Front. 2017, 1, 1194. [Non-Patent Document 5] N. Padial, J. Castells-Gil, N. Almora-Barrios, M. Romero-Angel, I. Silva, M. Barawi, A. Garcia-Sanchez, V. O'Shea, C. Marti-Gastaldo, J. Am. Chem. Soc. 2019, 141, 13124. [Overview of the project] [Problems that the invention aims to solve]

[0008] It is known that the structure of MOFs changes significantly depending on the metal species, ligands, and reaction conditions used. Regarding MOFs with hydroxamic acid as the binding site, there are few reported examples, and their storage capacity for gases other than nitrogen is unknown. The present invention aims to provide a storage material for gases other than nitrogen that contains an MOF with a hydroxamic acid group as the binding site. [Means for solving the problem]

[0009] The inventors of the present invention conducted diligent research to solve the above problems and found that MOFs can be obtained even with combinations of molecules having a metal species and hydroxamic acid as a binding site, other than those described in the prior art documents, and that these MOFs also have the capacity to store gases other than nitrogen, thus completing the present invention.

[0010] In other words, the present invention is defined as follows: [1] A storage material for gases other than nitrogen, containing a metal-organic structure formed by bonding a polyvalent metal ion with an unsubstituted or substituted hydroxamic acid group and a molecule having a site capable of binding to one or more polyvalent metal ions. [2] The storage material for gases other than nitrogen according to [1], wherein the site capable of binding to a polyvalent metal ion is a nitrogen atom in an unsubstituted or substituted hydroxamic acid group or a nitrogen-containing heterocyclic group. [3] The storage material for gases other than nitrogen according to [1] or [2], wherein the molecule having an unsubstituted or substituted hydroxamic acid group and a site capable of binding to one or more polyvalent metal ions is at least one selected from the group of compounds represented by the following formulas (I) to (III). [Chemical formula] (In formulas (I) to (III), R 1 , R 2 , R 4 , R 6 and R 7 each independently represents a hydrogen atom, a C1-6 alkyl group, a C6-10 aryl group, a C1-6 alkylcarbonyl group or a C6-10 arylcarbonyl group, and C(=O)N(R u )OH (u represents 1, 2, 4, 6 or 7.) may form a ring together with the carbon adjacent to the carbon of the ring to which it is bonded, R 3 , R 5 , R 8 and R 9 each independently represents a C1-6 alkyl group, a C3-8 cycloalkyl group, a C6-10 aryl group, a 3-6 member heterocyclyl group, a C1-6 alkoxy group, a C6-10 aryloxy group, a heteroaryloxy group, a halogeno group, a C1-6 haloalkyl group, a C6-10 haloaryl group, a C1-6 haloalkoxy group, a C1-6 alkylthio group, a C6-10 arylthio group, a heteroarylthio group, a C1-6 alkylsulfinyl group, a C6-10 arylsulfinyl group, a heteroarylsulfinyl group, a C1-6 alkylsulfonyl group, a C6-10 arylsulfonyl group, a heteroarylsulfonyl group, a cyano group, a nitro group or NR 11 R 12 represented group (wherein R 11 and R 12Each of these independently represents a hydrogen atom, a C1-6 alkyl group, a C6-10 aryl group, a C1-6 alkylcarbonyl group, or a C6-10 arylcarbonyl group. m is C(=O)N(R 2 ) Represents the number of groups represented by OH, and represents 1 or 2, and when m is 2, R 2 They may be identical or different. q is C(=O)N(R 7 ) Represents the number of groups represented by OH, and represents 1 or 2, and when q is 2, R 7 They may be identical or different. t is C(=O)N(R 6 ) Represents the number of groups represented by OH, and represents 1 or 2, and when t is 2, R 6 They may be identical or different. n is R 3 It represents the number of and also represents an integer of 0 or 1 to 4, and when n is 2 or greater, R 3 They may be identical or different. p is R 5 It represents the number of, and if A is a 5-membered ring, it represents 0 or an integer from 1 to 3, and if A is a 6-membered ring, it represents 0 or an integer from 1 to 4, and when p is 2 or greater, R 5 They may be identical or different. r is R 8 It represents the number of and also represents an integer of 0 or 1 to 4, and when r is 2 or greater, R 8 They may be the same or different. s is R 9 It represents the number of and an integer of 0 or 1 to 4, and when s is 2 or greater, R 9 They may be the same or different. However, n+m≦5, r+q≦5, and s+t≦5. In formula (II), A represents a 5- or 6-membered aromatic heterocycle containing 1 to 4 nitrogen atoms as ring constituent atoms. [4] A storage material for gases other than nitrogen as described in any one of [1] to [3], 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 of elements. [5] A storage material for gases other than nitrogen according to any one of [1] to [4], wherein the polyvalent metal ion is an ion of at least one metal selected from Zn, Fe, Co, Ni, Cu, Al, Zr, and Mg. [6] A method for storing a gas other than nitrogen, comprising the step of bringing a gas other than nitrogen into contact with a storage material for a gas other than nitrogen described in any one of [1] to [5], and adsorbing or storing the gas inside the storage material for a gas other than nitrogen. A storage tank for gases other than nitrogen, filled with a storage material for gases other than nitrogen as described in any one of [7][1] to [5]. [8] A metal-organic structure formed by bonding a polyvalent metal ion to a molecule having an unsubstituted or substituted hydroxamic acid group and a site capable of binding to one or more polyvalent metal ions (however, Ti 4+ or Zr 4+ (Excluding metal-organic structures formed by the bonding of benzene-1,4-dicarbohydroxamic acid.) [9] The metal-organic structure according to [8], wherein the molecule having an unsubstituted or substituted hydroxamic acid group and a site capable of binding to one or more polyvalent metal ions is selected from the group of compounds represented by the following formulas (I) to (III). [ka] (In formulas (I) to (III), R 1 , R 2 , R 4 , R 6 and R 7 Each of these independently represents a hydrogen atom, a C1-6 alkyl group, a C6-10 aryl group, a C1-6 alkylcarbonyl group, or a C6-10 arylcarbonyl group, and C(=O)N(R u )OH (where u = 1, 2, 4, 6, or 7) may form a ring together with the carbon adjacent to the carbon of the ring to which it is bonded. R 3 , R 5 , R8 and R 9 Each of these groups is independently a C1-6 alkyl group, a C3-8 cycloalkyl group, a C6-10 aryl group, a 3-6 membered heterocyclyl group, a C1-6 alkoxy group, a C6-10 aryloxy group, a heteroaryloxy group, a halogeno group, a C1-6 haloalkyl group, a C6-10 haloaryl group, a C1-6 haloalkoxy group, a C1-6 alkylthio group, a C6-10 arylthio group, a heteroarylthio group, a C1-6 alkylsulfinyl group, a C6-10 arylsulfinyl group, a heteroarylsulfinyl group, a C1-6 alkylsulfonyl group, a C6-10 arylsulfonyl group, a heteroarylsulfonyl group, a cyano group, a nitro group, or NR. 11 R 12 The base represented by (wherein R in the formula) 11 and R 12 Each of these independently represents a hydrogen atom, a C1-6 alkyl group, a C6-10 aryl group, a C1-6 alkylcarbonyl group, or a C6-10 arylcarbonyl group. m is C(=O)N(R 2 ) Represents the number of groups represented by OH, and represents 1 or 2, and when m is 2, R 2 They may be identical or different. q is C(=O)N(R 7 ) Represents the number of groups represented by OH, and represents 1 or 2, and when q is 2, R 7 They may be identical or different. t is C(=O)N(R 6 ) Represents the number of groups represented by OH, and represents 1 or 2, and when t is 2, R 6 They may be identical or different. n is R 3 It represents the number of and also represents an integer of 0 or 1 to 4, and when n is 2 or greater, R 3 They may be identical or different. p is R 5 It represents the number of, and if A is a 5-membered ring, it represents 0 or an integer from 1 to 3, and if A is a 6-membered ring, it represents 0 or an integer from 1 to 4, and when p is 2 or greater, R 5They may be identical or different. r is R 8 It represents the number of and also represents an integer of 0 or 1 to 4, and when r is 2 or greater, R 8 They may be the same or different. s is R 9 It represents the number of and an integer of 0 or 1 to 4, and when s is 2 or greater, R 9 They may be the same or different. However, n+m≦5, r+q≦5, and s+t≦5. In formula (II), A represents a 5- or 6-membered aromatic heterocycle containing 1 to 4 nitrogen atoms as ring constituent atoms.

[10] The metal-organic structure according to [8] or [9], 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 of elements.

[11] A metal-organic structure according to any one of [8] to

[10] , wherein the polyvalent metal ion is an ion of at least one metal selected from Zn, Fe, Co, Ni, Cu, Al, Zr, and Mg. [Effects of the Invention]

[0011] The gas storage material for gases other than nitrogen of the present invention is novel, and by using this material, gases such as hydrogen, carbon dioxide, methane, and acetylene (excluding nitrogen) can be stored. [Modes for carrying out the invention]

[0012] The gas storage material for gases other than nitrogen of the present invention contains a metal-organic structure formed by the bonding of a polyvalent metal ion with an unsubstituted or substituted hydroxamic acid group and a molecule having a site capable of binding to one or more polyvalent metal ions (hereinafter referred to as "hydroxamic acid group-containing molecule").

[0013] The polyvalent metal ions used in the present invention are not particularly limited as long as they are ions of metals with a valency of 2 or higher, but it is preferable that they be ions of at least one metal selected from the group consisting of metals in groups 2 to 13 of the periodic table, and more preferably at least one metal selected from Zn, Fe, Co, Ni, Cu, Al, Zr, and Mg, and even more preferably at least one metal selected from Co, Ni, Cu, and Zn. These can be used individually or in combination of two or more.

[0014] These polyvalent metal ions are supplied in the form of various salts, but considering the purity of the salt and the ease with which the metal ions bond with hydroxamic acid group-containing molecules, nitrates are preferred. Specifically, 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, etc.

[0015] The hydroxamic acid group-containing molecule used in the present invention is not particularly limited as long as it has at least one unsubstituted or substituted hydroxamic acid group within the molecule, and further has at least one site within the molecule that can bind to a polyvalent metal ion, and can bind to a polyvalent metal ion to construct an MOF.

[0016] In "unsubstituted or substituted hydroxamic acid group," "unsubstituted hydroxamic acid group" is represented by formula (IV-1) below, and "substituted hydroxamic acid group" represents any of the groups represented by formulas (IV-2) to (IV-4) below.

[0017] [ka]

[0018] In the formula, Ra and Rb each independently represent a functional group other than a hydrogen atom, specifically including C1-6 alkyl groups, C6-10 aryl groups, C1-6 alkylcarbonyl groups, C6-10 arylcarbonyl groups, etc. Furthermore, Ra may bond to an adjacent carbon to the carbon to which the carbonyl group is bonded to form a ring. Note that C1-6 in C1-6 alkylcarbonyl groups represent the number of carbon atoms in the alkyl group, and C6-10 in C6-10 arylcarbonyl groups represent the number of carbon atoms in the aryl group, and neither includes the carbon of the carbonyl group. The same applies hereafter.

[0019] The C1-6 alkyl groups may be linear or branched. Examples include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, i-propyl, i-butyl, s-butyl, t-butyl, i-pentyl, neopentyl, 2-methyl-n-butyl, and i-hexyl groups.

[0020] The C6-10 aryl group may be monocyclic or polycyclic, and in the case of a polycyclic aryl group, at least one ring may be an aromatic ring, while the remaining rings may be saturated alicyclic, unsaturated alicyclic, or aromatic. Specifically, examples include phenyl group, 1-naphthyl group, 2-naphthyl group, azulenyl group, indenyl group, indanyl group, tetralinyl group, etc. Examples of C1-6 alkylcarbonyl groups include acetyl group, n-propionyl group, isopropionyl group, n-butyryl group, isobutyryl group, pivaloyl group, and n-pentanoyl group. Examples of C6-10 arylcarbonyl groups include benzoyl groups, 1-naphthylcarbonyl groups, and 2-naphthylcarbonyl groups.

[0021] Furthermore, the following structure is an example of a structure where "Ra may bond with an adjacent carbon to the carbon to which the carbonyl group is bonded to form a ring."

[0022] [ka]

[0023] In the context of "sites capable of binding to polyvalent metal ions," the term "binding" refers to chemical bonds such as ionic bonds and coordination bonds between the metal ion and the molecule. Specifically, preferred sites that can bind to polyvalent metal ions include unsubstituted or substituted hydroxamic acid groups or nitrogen atoms in nitrogen-containing heterocyclic groups. Examples of unsubstituted or substituted hydroxamic acid groups include those similar to the hydroxamic acid groups described above.

[0024] Specifically, the "nitrogen-containing heterocyclic groups" in "nitrogen atoms in nitrogen-containing heterocyclic groups" include: 3-pyrrolyl group, 2-imidazolyl group, 3-pyrazolyl group, 2-oxazolyl group, 2-thiazolyl group, 3-isoxazolyl group, 3-isothiazolyl group, 1,2,3-triazolo-4-yl group, 1,2,4-triazolo-3-yl group, 1,2,3-oxadiazolyl-4-yl group, and 1,2,4-thiadiazolyl-4 Examples include -yl group, 1,2,4-oxadiazolyl-3-yl group, 1,2,4-thiadiazolyl-3-yl group, 1,3,4-oxadiazolyl-2-yl group, 1,3,4-thiadiazolyl-2-yl group, 4-pyridyl group, 3-pyridyl group, 2-pyridyl group, 4-pyrimidyl group, 3-pyridazyl group, 2-pyradyl group, 1,3,5-triazyl-2-yl group, 3-pyrrolidyl group, 4-piperidyl group, etc.

[0025] More specifically, the hydroxamic acid group-containing molecule used in the present invention is preferably at least one selected from the group of compounds represented by formulas (I) to (III). The hydroxamic acid group-containing molecule can be used alone or as a mixture of two or more.

[0026] In formulas (I) to (III), R 1 , R 2 , R 4 , R 6 and R 7Each of these independently represents a hydrogen atom, a C1-6 alkyl group, a C6-10 aryl group, a C1-6 alkylcarbonyl group, or a C6-10 arylcarbonyl group, and C(=O)N(R u )OH (where u = 1, 2, 4, 6, or 7) may form a ring with a carbon adjacent to the carbon atom of the ring to which it is bonded.

[0027] Specifically, examples of C1-6 alkyl groups, C6-10 aryl groups, C1-6 alkylcarbonyl groups, and C6-10 arylcarbonyl groups can be given that are similar to the examples given above for Ra. Also, "C(=O)N(R u )OH(u=1, 2, 4, 6, or 7) may form a ring together with an adjacent carbon atom to which it is bonded. The same examples as those exemplified in Ra above can also be given for ".

[0028] R 3 , R 5 , R 8 and R 9 Each of these groups is independently a C1-6 alkyl group, a C3-8 cycloalkyl group, a C6-10 aryl group, a 3-6 membered heterocyclyl group, a C1-6 alkoxy group, a C6-10 aryloxy group, a heteroaryloxy group, a halogeno group, a C1-6 haloalkyl group, a C6-10 haloaryl group, a C1-6 haloalkoxy group, a C1-6 alkylthio group, a C6-10 arylthio group, a heteroarylthio group, a C1-6 alkylsulfinyl group, a C6-10 arylsulfinyl group, a heteroarylsulfinyl group, a C1-6 alkylsulfonyl group, a C6-10 arylsulfonyl group, a heteroarylsulfonyl group, a cyano group, a nitro group, or NR. 11 R 12 The base represented by (wherein R in the formula) 11 and R 12 Each of these independently represents a hydrogen atom, a C1-6 alkyl group, a C6-10 aryl group, a C1-6 alkylcarbonyl group, or a C6-10 arylcarbonyl group.

[0029] C1-6 alkyl groups may be linear or branched, and examples include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, i-propyl group, i-butyl group, s-butyl group, t-butyl group, i-pentyl group, neopentyl group, 2-methyl-n-butyl group, i-hexyl group, etc.

[0030] Examples of C3-8 cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cubanyl groups.

[0031] The C6-10 aryl group may be monocyclic or polycyclic, and in the case of a polycyclic aryl group, at least one ring may be an aromatic ring, while the remaining rings may be saturated alicyclic, unsaturated alicyclic, or aromatic. Specifically, examples include phenyl group, 1-naphthyl group, 2-naphthyl group, azulenyl group, indenyl group, indanyl group, tetralinyl group, etc.

[0032] A 3-6 membered heterocyclyl group contains 1 to 4 heteroatoms selected from the group consisting of nitrogen, oxygen, and sulfur atoms as constituent atoms of the ring. The heterocyclyl group may be monocyclic or polycyclic. In a polycyclic heterocyclyl group, at least one ring may be a heterocyclic ring, and the remaining rings may be saturated alicyclic, unsaturated alicyclic, or aromatic hydrocarbon rings. Examples of 3-6 membered heterocyclyl groups include 3-6 membered saturated heterocyclyl groups, 5-6 membered heteroaryl groups, and 5-6 membered partially unsaturated heterocyclyl groups.

[0033] Examples of 3-6 membered saturated heterocyclyl groups include azilidinyl group, epoxy group, pyrrolidinyl group, tetrahydrofuryl group, thiazolidinyl group, piperidyl group, piperazinyl group, morpholinyl group, dioxolanyl group, and dioxanyl group.

[0034] Examples of 5-membered heteroaryl groups include pyrrolyl, furyl, thienyl, imidazolyl, pyrazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, triazolyl, oxadiazolyl, thiadiazolyl, tetrazolyl, indonyl, isoindolinyl, indolidinyl, benzimidazolyl, and carbazolyl groups. Examples of six-membered heteroaryl groups include pyridyl, pyrazyl, pyrimidyl, pyridazyl, triazyl, quinolinyl, isoquinolinyl, quinoxalinyl, cinolinyl, quinazolyl, phthalazinyl, acridinyl, naftazinyl, and phenazinyl groups.

[0035] Examples of C1-6 alkoxy groups include methoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, s-butoxy, i-butoxy, and t-butoxy groups. Examples of C6-10 aryloxy groups include phenoxy group, 1-naphthyloxy group, 2-naphthyloxy group, azulenyloxy group, indenyloxy group, indanyloxy group, and tetralinyloxy group.

[0036] Examples of heteroaryloxy groups include furyloxy groups, thiazolyloxy groups, and pyridyloxy groups. Examples of halogen groups include fluoro groups, chloro groups, bromo groups, and iod groups. Examples of C1-6 haloalkyl groups include fluoromethyl group, difluoromethyl group, trifluoromethyl group, 2,2,2-trifluoroethyl group, pentafluoroethyl group, 3,3,3-trifluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, perfluoropropyl group, 2,2,2-trifluoro-1-trifluoromethylethyl group, perfluoroisopropyl group, 4-fluorobutyl group, 2,2,3,3,4,4,4-heptafluorobutyl group, perfluorobutyl group, perfluoropentyl group, perfluorohexyl group, chloromethyl group, bromomethyl group, dichloromethyl group, dibromomethyl group, trichloromethyl group, tribromomethyl group, 1-chloroethyl group, 2,2,2-trichloroethyl group, 4-chlorobutyl group, perchlorohexyl group, and 2,4,6-trichlorohexyl group. Examples of C6-10 haloaryl groups include 4-chlorophenyl, 3,5-dichlorophenyl, 2,4,6-trichlorophenyl, and 2,3,4,5,6-pentafluorophenyl. Examples of C1-6 haloalkoxy groups include trifluoromethoxy, 2,2,2-trifluoroethoxy, pentafluoroethoxy, 3,3,3-trifluoropropoxy, 2,2,3,3,3-pentafluoropropoxy, perfluoropropoxy, 2,2,2-trifluoro-1-trifluoromethylethoxy, perfluoroisopropoxy, 4-fluorobutoxy, 2,2,3,3,4,4,4-heptafluorobutoxy, perfluorobutoxy, perfluoropentoxy, perfluorohexyloxy, 2,2,2-trichloroethoxy, 4-chlorobutoxy, perchlorohexyloxy, and 2,4,6-trichlorohexyloxy.

[0037] Examples of C1-6 alkylsulfanyl groups include methylsulfanyl group, ethylsulfanyl group, n-propylsulfanyl group, i-propylsulfanyl group, n-butylsulfanyl group, i-butylsulfanyl group, s-butylsulfanyl group, and t-butylsulfanyl group. Examples of C6-10 arylsulfanyl groups include phenylsulfanyl group, 1-naphthylsulfanyl group, 2-naphthylsulfanyl group, azulenylsulfanyl group, indenylsulfanyl group, indanylsulfanyl group, and tetralinylsulfanyl group. Examples of heteroarylsulfanil groups include furylsulfanil groups, thiazolylsulfanil groups, and pyridylsulfanil groups.

[0038] Examples of C1-6 alkylsulfinyl groups include methylsulfinyl group, ethylsulfinyl group, and t-butylsulfinyl group. Examples of C6-10 arylsulfinyl groups include phenylsulfinyl group, 1-naphthylsulfinyl group, 2-naphthylsulfinyl group, azulenylsulfinyl group, indenylsulfinyl group, indanylsulfinyl group, and tetralinylsulfinyl group. Examples of heteroarylsulfinyl groups include furylsulfinyl groups, thiazolylsulfinyl groups, and pyridylsulfinyl groups.

[0039] Examples of C1-6 alkylsulfonyl groups include methylsulfonyl groups, ethylsulfonyl groups, and t-butylsulfonyl groups. Examples of C6-10 arylsulfonyl groups include phenylsulfonyl group, 1-naphthylsulfonyl group, 2-naphthylsulfonyl group, azulenylsulfonyl group, indenylsulfonyl group, indanylsulfonyl group, and tetralinylsulfonyl group. Examples of heteroarylsulfonyl groups include furylsulfonyl groups, thiazolylsulfonyl groups, and pyridylsulfonyl groups.

[0040] NR 11 R 12 In the base represented by R 11 and R 12 Each of these independently represents a hydrogen atom, a C1-6 alkyl group, a C6-10 aryl group, a C1-6 alkylcarbonyl group, or a C6-10 arylcarbonyl group. Examples of the C1-6 alkyl group and the C6-10 aryl group include those exemplified for R above. 3 , R 5 , R 8 and R 9 are the same as those exemplified above. Examples of the C1-6 alkylcarbonyl group and the C6-10 arylcarbonyl group include those exemplified for Ra above. NR 11 , R 12 Examples of the group represented by include an amino group, a methylamino group, a dimethylamino group, an ethyl-i-propylamino group, an anilino group, a diphenylamino group, an acetylamino group, a benzoylamino group, and the like.

[0041] In formula (II), A represents a 5- or 6-membered aromatic heterocycle containing 1 to 4 nitrogen atoms as ring-constituting atoms, and it may be either a monocyclic or polycyclic ring. However, in the case of a polycyclic ring, at least one ring is a heterocycle, and the remaining rings are any of saturated alicyclic, unsaturated alicyclic, or aromatic hydrocarbon rings. Examples of such aromatic heterocycles include a pyrrolyl 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, a tetrazolyl group, a pyridyl group, a pyrazyl group, a pyrimidyl group, a pyridazyl group, a triazolyl group, an indolyl group, an isoindolinyl group, an indolizinyl group, a benzimidazolyl group, a carbazolyl group, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group, a cinnolinyl group, a quinazolinyl group, a phthalazinyl group, an acridinyl group, a naphthidinyl group, a phenazinyl group, and the like. <( <(

[0042] <( R 1 , R 2 , R 4 , R 6 and R 7 The C1-6 alkyl group, C6-10 aryl group, C1-6 alkylcarbonyl group or C6-10 arylcarbonyl group in R 3 , R 5 , R 8 and R 9C1-6 alkyl groups, C3-8 cycloalkyl groups, C6-10 aryl groups, 3-6 membered heterocyclyl groups, C1-6 alkoxy groups, C6-10 aryloxy groups, heteroaryloxy groups, halogeno groups, C1-6 haloalkyl groups, C6-10 haloaryl groups, C1-6 haloalkoxy groups, C1-6 alkylthio groups, C6-10 arylthio groups, heteroarylthio groups, C1-6 alkylsulfinyl groups, C6-10 arylsulfinyl groups, heteroarylsulfinyl groups, C1-6 alkylsulfonyl groups, C6-10 arylsulfonyl groups, heteroarylsulfonyl groups or NR 11 R 12 The base represented by (wherein R in the formula) 11 and R 12 Each of these independently represents a hydrogen atom, a C1-6 alkyl group, a C6-10 aryl group, a C1-6 alkylcarbonyl group, or a C6-10 arylcarbonyl group. ) may have further substituents as needed, within a chemically acceptable range.

[0043] Examples of such substituents include the following groups. C1-6 alkyl groups such as methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, s-butyl group, i-butyl group, t-butyl group, n-pentyl group, and n-hexyl group; C2-6 alkenyl groups such as vinyl group, 1-propenyl group, 2-propenyl group (allyl group), propen-2-yl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 1-methyl-2-propenyl group, and 2-methyl-2-propenyl group; C2-6 alkynyl groups such as ethynyl group, 1-propynyl group, 2-propynyl group (propargyl group), 1-butynyl group, 2-butynyl group, 3-butynyl group, and 1-methyl-2-propynyl group;

[0044] C3-8 cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cubanyl groups; C6-10 aryl groups such as phenyl and naphthyl groups; C6-10 aryl C1-6 alkyl groups such as benzyl and phenethyl groups; 3-6 member heterocyclyl group; 3-6 member heterocyclyl C1-6 alkyl group;

[0045] Oxo group; Hydroxyl group; C1-6 alkoxy groups such as methoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, s-butoxy, i-butoxy, and t-butoxy groups; C2-6 alkenyloxy groups such as vinyloxy groups, allyloxy groups, 1-propenyloxy groups, propen-2-yloxy groups, 3-butenyloxy groups, and 2-butenyloxy groups; C2-6 alkynyloxy groups such as ethynyloxy groups and propargyloxy groups; C6-10 aryloxy groups such as phenoxy and naphthoxy groups; C6-10 aryl C1-6 alkoxy groups such as benzyloxy groups and phenethyloxy groups; 5-6 member heteroaryloxy groups such as thiazolyloxy and pyridyloxy groups; 5-6 member heteroaryl C1-6 alkyloxy groups such as thiazolylmethyloxy group and pyridylmethyloxy group;

[0046] Formyl group; C1-6 alkylcarbonyl groups such as acetyl groups and propionyl groups; Formyloxy group; C1-6 alkylcarbonyloxy groups such as acetyloxy groups and propionyloxy groups; C6-10 arylcarbonyl groups such as benzoyl groups; C1-6 alkoxycarbonyl groups such as methoxycarbonyl groups, ethoxycarbonyl groups, n-propoxycarbonyl groups, i-propoxycarbonyl groups, n-butoxycarbonyl groups, and t-butoxycarbonyl groups; C1-6 alkoxycarbonyloxy groups such as methoxycarbonyloxy groups, ethoxycarbonyloxy groups, n-propoxycarbonyloxy groups, i-propoxycarbonyloxy groups, n-butoxycarbonyloxy groups, and t-butoxycarbonyloxy groups; Carboxy group;

[0047] Halogeno groups such as fluoro groups, chloro groups, bromo groups, and iod groups; C1-6 haloalkyl groups such as fluoromethyl group, difluoromethyl group, trifluoromethyl group, 2,2,2-trifluoroethyl group, pentafluoroethyl group, 3,3,3-trifluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, perfluoropropyl group, 2,2,2-trifluoro-1-trifluoromethylethyl group, perfluoroisopropyl group, 4-fluorobutyl group, 2,2,3,3,4,4,4-heptafluorobutyl group, perfluorobutyl group, perfluoropentyl group, perfluorohexyl group, chloromethyl group, bromomethyl group, dichloromethyl group, dibromomethyl group, trichloromethyl group, tribromomethyl group, 1-chloroethyl group, 2,2,2-trichloroethyl group, 4-chlorobutyl group, perchlorohexyl group, and 2,4,6-trichlorohexyl group; C2-6 haloalkenyl groups such as 2-chloro-1-propenyl group and 2-fluoro-1-butenyl group; C2-6 haloalkynyl groups such as 4,4-dichloro-1-butynyl, 4-fluoro-1-pentynyl, and 5-bromo-2-pentynyl; C1-6 haloalkoxy groups such as trifluoromethoxy, 2-chloro-n-propoxy, and 2,3-dichlorobutoxy; C2-6 haloalkenyloxy groups such as 2-chloropropenyloxy groups and 3-bromobutenyloxy groups; C1-6 haloalkylcarbonyl groups such as chloroacetyl, trifluoroacetyl, and trichloroacetyl groups;

[0048] amino group; C1-6 alkyl-substituted amino groups such as methylamino groups, dimethylamino groups, and diethylamino groups; C6-10 arylamino groups such as anilino groups and naphthylamino groups; C6-10 aryl C1-6 alkylamino groups such as benzylamino groups and phenethylamino groups; Formylamino group; C1-6 alkylcarbonylamino groups such as acetylamino groups, propanoylamino groups, butyrylamino groups, and i-propylcarbonylamino groups; C1-6 alkoxycarbonylamino groups such as methoxycarbonylamino groups, ethoxycarbonylamino groups, n-propoxycarbonylamino groups, and i-propoxycarbonylamino groups; C1-6 alkyl sulfoxiimino groups such as S,S-dimethyl sulfoxiimino groups; Unsubstituted or substituted aminocarbonyl groups such as aminocarbonyl groups, dimethylaminocarbonyl groups, phenylaminocarbonyl groups, and N-phenyl-N-methylaminocarbonyl groups; Imino C1-6 alkyl groups such as iminomethyl group, 1-iminoethyl group, and 1-imino-n-propyl group; Substituted or unsubstituted N-hydroxyimino C1-6 alkyl groups such as N-hydroxyiminomethyl group, 1-(N-hydroxyimino)ethyl group, 1-(N-hydroxyimino)propyl group, N-methoxyiminomethyl group, and 1-(N-methoxyimino)ethyl group; Hydroxyimino group; C1-6 alkoxyimino groups such as methoxyimino groups, ethoxyimino groups, n-propoxyimino groups, i-propoxyimino groups, and n-butoxyimino groups; aminocarbonyloxy group; C1-6 alkyl-substituted aminocarbonyloxy groups such as ethylaminocarbonyloxy groups and dimethylaminocarbonyloxy groups;

[0049] Thioxo group; Sulfanyl group; C1-6 alkylsulfanyl groups such as methylsulfanyl group, ethylsulfanyl group, n-propylsulfanyl group, i-propylsulfanyl group, n-butylsulfanyl group, i-butylsulfanyl group, s-butylsulfanyl group, and t-butylsulfanyl group; C1-6 haloalkylsulfanyl groups such as trifluoromethylsulfanyl group and 2,2,2-trifluoroethylsulfanyl group; C6-10 arylsulfanyl groups such as phenylsulfanyl groups and naphthylsulfanyl groups; 5-6 member heteroaryl sulfanyl groups such as thiazolyl sulfanyl groups and pyridyl sulfanyl groups;

[0050] C1-6 alkyl sulfinyl groups such as methyl sulfinyl group, ethyl sulfinyl group, and t-butyl sulfinyl group; C1-6 haloalkylsulfinyl groups such as trifluoromethylsulfinyl group and 2,2,2-trifluoroethylsulfinyl group; C6-10 arylsulfinyl groups such as phenylsulfinyl groups; 5-6 member heteroaryl sulfinyl groups such as thiazolyl sulfinyl groups and pyridyl sulfinyl groups;

[0051] C1-6 alkylsulfonyl groups such as methylsulfonyl groups, ethylsulfonyl groups, and t-butylsulfonyl groups; C1-6 haloalkylsulfonyl groups such as trifluoromethylsulfonyl group and 2,2,2-trifluoroethylsulfonyl group; C6-10 arylsulfonyl groups such as phenylsulfonyl groups; 5-6 member heteroarylsulfonyl groups such as thiazolylsulfonyl groups and pyridylsulfonyl groups; sulfo group; C1-6 alkyl sulfonyl groups such as methyl sulfonyloxy groups, ethyl sulfonyloxy groups, and t-butyl sulfonyloxy groups; C1-6 haloalkylsulfonyloxy groups such as trifluoromethylsulfonyloxy groups and 2,2,2-trifluoroethylsulfonyloxy groups;

[0052] TriC1-6 alkyl-substituted silyl groups such as trimethylsilyl group, triethylsilyl group, and 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 allyldimethylsilyl groups and vinyldimethylsilyl groups; C1-C6 alkyldiC6-C10 aryl-substituted silyl groups such as t-butyldiphenylsilyl group and diphenylmethylsilyl group; DiC1-C6 alkylC6-C10 aryl-substituted silyl groups such as dimethylphenylsilyl groups; (C6-C10 phenyl C1-C6 alkyl) diC1-C6 alkylsilyl groups such as benzyldimethylsilyl group and 3-phenylpropyldimethylsilyl group; C1-C6 alkyl C6-C10 phenyl C2-C6 alkenylsilyl groups such as methylphenylvinylsilyl groups; Tri-C1-C6 alkoxy-substituted silyl groups such as trimethoxysilyl and triethoxysilyl groups; DiC1-C6 alkyl-substituted silyl groups such as dimethylsilyl and diethylsilyl groups; Di-C1-C6 alkoxy-substituted silyl groups such as dimethoxysilyl and diethoxysilyl groups; C1-C6 alkoxyC1-C6 alkyl-substituted silyl groups such as methoxydimethylsilyl groups; C1-C6 alkoxyC6-C10 aryl-substituted silyl groups such as t-butoxydiphenylsilyl groups; C1-C6 alkyldiC1-C6 alkoxy-substituted silyl groups such as methyldimethoxysilyl groups; Cyano group; Nitro group.

[0053] Furthermore, the above-mentioned "3-6 membered heterocyclyl group" refers to a group containing 1 to 4 heteroatoms selected from the group consisting of nitrogen, oxygen, and sulfur atoms as constituent atoms of the ring. The heterocyclyl group may be monocyclic or polycyclic. In a polycyclic heterocyclyl group, at least one ring may be a heterocyclic ring, and the remaining rings may be saturated alicyclic, unsaturated alicyclic, or aromatic hydrocarbon rings. Examples of "3-6 membered heterocyclyl groups" include 3-6 membered saturated heterocyclyl groups, 5-6 membered heteroaryl groups, and 5-6 membered partially unsaturated heterocyclyl groups.

[0054] Examples of 3-6 member saturated heterocyclyl groups include azilidinyl group, epoxy group, pyrrolidinyl group, tetrahydrofuryl group, thiazolidinyl group, piperidyl group, piperazinyl group, morpholinyl group, dioxolanyl group, and dioxanyl group.

[0055] Examples of 5-membered heteroaryl groups include pyrrolyl, furyl, thienyl, imidazolyl, pyrazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, triazolyl, oxadiazolyl, thiadiazolyl, tetrazolyl, indonyl, isoindolinyl, indolidinyl, benzimidazolyl, and carbazolyl groups. Examples of six-membered heteroaryl groups include pyridyl, pyrazinyl, pyrimidinyl, pyridadinyl, triazinyl, quinolinyl, isoquinolinyl, quinoxalinyl, cinolinyl, quinazolyl, phthalazinyl, acridinyl, naftazinyl, and phenazinyl groups. Examples of 5-6 membered partial unsaturated heterocyclyl groups include isoxazolinyl groups and pyrazolinyl groups. Examples of 3- to 6-membered heterocyclyl 1- to 6-alkyl groups include glycidyl group, 2-tetrahydrofurylmethyl group, 2-pyrrolylmethyl group, 2-imidazolylmethyl group, 3-isoxazolylmethyl group, 5-isoxazolylmethyl group, 2-pyridylmethyl group, 4-pyridylmethyl group, and 3-isoxazolinylmethyl group.

[0056] Specific examples of compounds represented by formula (I) include the compounds represented by the following formulas.

[0057] [ka]

[0058] [ka]

[0059] Specific examples of compounds represented by formula (II) include the compounds represented by the following formulas.

[0060] [ka]

[0061] Specific examples of compounds represented by formula (III) include the compounds represented by the following formulas.

[0062] [ka]

[0063] [ka]

[0064] [ka]

[0065] The gas storage material for gases other than nitrogen of the present invention contains a metal-organic structure formed by the bonding of a polyvalent metal ion and a hydroxamic acid group-containing molecule. In this invention, the bonding in "metal-organic structure formed by the bonding of a polyvalent metal ion and a hydroxamic acid group-containing molecule" refers to chemical bonds such as ionic bonds and coordination bonds between the polyvalent metal ion and the hydroxamic acid group-containing molecule.

[0066] In the metal-organic structure used as a storage material for gases other than nitrogen according to the present invention, molecules containing nitrogen atoms (excluding molecules containing hydroxamic acid groups) (hereinafter referred to as nitrogen atom-containing molecules) can be included as constituent units in addition to hydroxamic acid group-containing molecules. Examples of such molecules include isonicotinic 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 bis(3-(4-pyridyl)-2,4-pentanedionato)copper.

[0067] When using hydroxamic acid group-containing molecules and nitrogen atom-containing molecules, the mixing molar ratio is not particularly limited. However, for example, when using nitrogen atom-containing molecules as pillar molecules and crosslinking them to construct a three-dimensional structure such as a pillared layer, it is preferable to use nitrogen atom-containing molecules in excess of hydroxamic acid group-containing molecules.

[0068] The present invention provides a method for producing metal-organic structures used as storage materials for gases other than nitrogen. Any of these methods are not particularly limited and can be used, including solution methods such as solvent diffusion, solvent stirring, and hydrothermal methods; microwave methods in which microwaves are irradiated onto the reaction solution to uniformly heat the entire system in a short time; ultrasonic methods in which ultrasound is irradiated onto the reaction vessel to repeatedly cause pressure changes in the vessel, and these pressure changes cause a phenomenon called cavitation in which the solvent forms bubbles and collapses, at which point a high-energy field of about 5000K and 10000 bar is locally formed, which serves as the reaction field for the formation of each crystal; solid-phase synthesis methods in which a metal ion source and an organic ligand are mixed without using a solvent; and LAG (liquid-assisted grinding) methods in which water in the amount of crystal water is added to mix the metal ion source and a molecule containing a hydroxamic acid group.

[0069] For example, the process includes the steps of preparing a first solution containing a metal compound that serves as a source of metal ions and a solvent, a second solution containing a hydroxamic acid group-containing molecule and a solvent, and, if necessary, a third solution containing another compound that acts as a polydentate ligand and a solvent, and then mixing the first solution with the second and third solutions to prepare a reaction solution, and heating this reaction solution to obtain a metal-organic structure. The first to third solutions do not need to be prepared separately; for example, the metal compound, the hydroxamic acid group-containing molecule, the other compound that acts as a polydentate ligand, and the solvent may be mixed at once to prepare a single solution.

[0070] The molar ratio of the above-mentioned metal compound to the hydroxamic acid group-containing molecule can be arbitrarily selected depending on the pore size and surface properties of the resulting metal-organic structure. However, it is preferable to use 1 mole or more of the metal compound per mole of hydroxamic acid group-containing molecule, and even more preferably 1.1 moles or more, 1.2 moles or more, 1.5 moles or more, 2 moles or more, and 3 moles or more.

[0071] The concentration of the above metal ions in the reaction solution is preferably in the range of 25 to 200 mol / L. The concentration of the hydroxamic acid group-containing molecule in the reaction solution is preferably in the range of 10 to 100 mol / L. The concentration of organic ligands other than the hydroxamic acid group-containing molecule in the reaction solution is preferably 25 to 100 mol / L.

[0072] 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 (hereinafter sometimes referred to as "DMA"), and water. Among these, it is preferable to use N,N-dimethylformamide, N,N-diethylformamide, or N,N-dimethylacetamide alone, or to use a mixed solvent of N,N-dimethylformamide / water, N,N-diethylformamide / water, or N,N-dimethylacetamide / water.

[0073] The heating temperature of the reaction solution is not particularly limited, but it is preferably in the range of room temperature to 140°C.

[0074] The gas to be stored in the gas storage material other than nitrogen of the present invention is not particularly limited as long as it is a gas that can be stored in the material, but specifically, examples include hydrogen, carbon dioxide, methane, acetylene, etc., with hydrogen and carbon dioxide being preferred among them. However, nitrogen is excluded. Hereinafter, "gas" refers to gases other than nitrogen. The method of storing gas using the gas storage material of the present invention is not particularly limited, but a method of bringing the gas storage material of the present invention into contact with gas is preferred, and the method of contact is not particularly limited. For example, this could include filling a tank with the gas storage material of the present invention to form a gas storage tank and then introducing gas into the tank; supporting the gas storage material of the present invention on the surface constituting the inner wall of a tank to form a gas storage tank and then introducing gas into the tank; or forming a tank from a material containing the gas storage material of the present invention to form a gas storage tank and then introducing gas into the tank. The gas storage tank of the present invention can be constructed by sealing and molding a material that can withstand atmospheric or high pressure so that it has a space inside in which gas can be stored, and then filling the molded tank with the gas storage material of the present invention. Furthermore, in another embodiment of the gas storage tank of the present invention, a material containing the gas storage material of the present invention may be sealed and molded into a shape that has a space into which gas can flow. The material containing the gas storage material of the present invention refers to the gas storage material of the present invention itself, or a material that combines the gas storage material of the present invention with other moldable materials. These embodiments may constitute the gas storage tank of the present invention individually or in combination. [Examples]

[0075] The present invention will be described in detail below using examples, but the present invention is not limited to the scope of these examples. The compounds shown in Table 1 below were used as hydroxamic acid group-containing molecules constituting the metal-organic structure used in the gas storage material of the present invention.

[0076] [Table 1]

[0077] (Reference Example 1) Synthesis of compound number 9 Diethyl 2,5-dihydroxyterephthalate (6.5 mmol), isopropyl bromide (25.8 mmol), potassium carbonate (138 mmol), and 20 mL of DMF were heated under nitrogen at 60°C for 24 hours. After returning to room temperature, water was added and the mixture was separated. The organic layer extracted with chloroform was dried over magnesium sulfate and filtered. The filtrate was removed by reduced pressure, and the resulting solid was purified using silica gel column chromatography (chloroform). 1.6 g (4.7 mmol) of diethyl 2,5-diisopropoxyterephthalate was obtained as a colorless solid. To 10 mL of methanol solution of hydroxylamine hydrochloride (80 mmol), 15 mL of methanol solution of potassium hydroxide (80 mmol) was added at 0°C and stirred for 5 minutes. The filtrate was added to diethyl 2,5-diisopropoxyterephthalate and stirred at room temperature for 5 hours. 1N hydrochloric acid was added until a precipitate formed, and the precipitated solid was filtered. The mixture was thoroughly washed with ethyl acetate and water, and then vacuum-dried to obtain 1.4 g (4.0 mmol) of 2,5-diisopropoxy-1,4-benzene-dicarbohydroxamic acid (compound No. 9).

[0078] (Reference Example 2) Synthesis of Compound No. 10 2,5-dimethylterephthalic acid (4.0 mmol), oxalyl chloride (10 mmol), and 10 mL of THF were stirred overnight under nitrogen at room temperature. Volatile substances were removed by distillation under reduced pressure, and acetonitrile was added to the residue to prepare an acid chloride solution. N-methylhydroxylamine hydrochloride (8.8 mmol), imidazole (16 mmol), and 20 mL of acetonitrile were added and stirred for 10 minutes. The aforementioned acid chloride solution was then added to this solution and stirred at room temperature for 15 hours. The precipitated solid was filtered, washed thoroughly with water, and vacuum dried to obtain 0.6 g (2.4 mmol) of 2,5-dimethyl-1,4-benzene-di(N-methylcarbohydroxamic acid) (compound No. 10).

[0079] [Example 1-1] Compound No. 1 (0.5 mmol) and zinc nitrate hexahydrate (1.0 mmol) were mixed with 10 mL of DMF and heated in an oven (reaction conditions: 120°C, 24 hours). After returning to room temperature, the mixture was centrifuged and the supernatant was removed. After washing with 10 mL of DMF, the solvent was removed and replaced with chloroform. 10 mL of chloroform was added and the mixture was immersed overnight. After removing the chloroform, the mixture was vacuum-dried at 150°C for 5 hours to obtain metal-organic structure 1 as a light brown solid.

[0080] [Examples 1-2] to [Examples 1-31] Except for using the organic ligands and solvents shown in Table 2 and carrying out the reaction under the reaction conditions (temperature and heating time) shown in Table 2, the same procedure as in Example 1-1 was followed to obtain metal-organic structures 1-2 to 1-31. The results are shown in Table 2.

[0081] [Table 2]

[0082] [Example 2-1] Compound No. 1 (1.2 mmol) and zinc nitrate hexahydrate (1.6 mmol) were added to 40 mL of DMF. Triethylamine (14.4 mmol) was added dropwise, and the mixture was stirred at room temperature for 30 minutes. The precipitate was filtered, and the precipitate was washed three times with 10 mL of DMF. Then, the precipitate was washed three times with 10 mL of chloroform. The mixture was immersed overnight in 10 mL of chloroform, filtered, and the solid was vacuum-dried at 150°C for 5 hours to obtain metal-organic structure 2-1 as a white solid.

[0083] [Example 2-2]~[Example 2-6] Metal-organic structures 2-2 to 2-6 were obtained by following the same procedure as in Example 2-1, except that the compounds and solvents shown in Table 3 were used and the reaction times shown in Table 3 were used. The results are shown in Table 3.

[0084] [Table 3]

[0085] [Example 3-1] Compound No. 1 (0.5 mmol), zinc nitrate hexahydrate (0.5 mmol), and isonicotinic acid (0.5 mmol) were mixed with 3 mL of DMF and 1 mL of water, and heated in an oven (reaction conditions: 120°C, 12 hours). After returning to room temperature, the solid was washed with 10 mL of DMF and then immersed in 10 mL of DMF overnight. The solid, which was the filtration product, was washed three times with 10 mL of chloroform. After immersion in 10 mL of chloroform overnight and filtration, the solid was vacuum-dried at 150°C for 5 hours to obtain metal-organic structure 3-1 as a white solid.

[0086] [Example 3-2]~[Example 3-8] Except for using the compounds, metal salts, and solvents shown in Table 4 below, and carrying out the reaction under the reaction conditions (temperature and heating time) shown in Table 4, the same procedure as in Example 3-1 was followed to obtain metal-organic structures 3-2 to 3-8. The results are shown in Table 4.

[0087] [Table 4]

[0088] [Examples 3-9] Except for halving the solid content concentration in the solution (representing the concentration (g / v) of each compound, metal salt, and isonicotinic acid in the solution for each compound number listed in Table 4), the procedure was carried out in the same manner as in Example 3-3 to obtain metal-organic structure 3-9 as a red crystal.

[0089] [Examples 3-10] Except for halving the solid content concentration in the solution (representing the concentration (g / v) of each compound, metal salt, and isonicotinic acid in the solution for each compound number listed in Table 4), the procedure was carried out in the same manner as in Example 3-4 to obtain metal-organic structure 3-10 as a mixture of black, pink, and brown.

[0090] [Example 4-1] Compound No. 1 (0.25 mmol), zinc nitrate hexahydrate (0.25 mmol), and 1,4-diazabicyclo[2.2.2]octane (DABCO) (0.25 mmol) as an auxiliary ligand were mixed with 3.3 mL of DMF and 6.6 mL of DEF as solvents, and heated in an oven (reaction conditions: 90°C, 24 hours). After returning to room temperature, the solid was washed three times with 10 mL of DMF, and then the solid filtrate was washed three times with 10 mL of chloroform. The mixture was immersed overnight in 10 mL of chloroform, filtered, and then vacuum-dried at 150°C for 5 hours to obtain metal-organic structure 4-1 as a white solid.

[0091] [Examples 4-2] to [Examples 4-5] Except for using the compounds, auxiliary ligands, and solvents shown in Table 5 below, and carrying out the reaction under the reaction conditions (temperature and time) shown in Table 5, the same procedure as in Example 4-1 was followed to obtain metal-organic structures 4-2 to 4-5. The results are shown in Table 5.

[0092] [Table 5]

[0093] [Example 5-1] Compound No. 1 (0.5 mmol) was dissolved in 7 mL of DMF. 8 mL of a solution of zinc acetate dihydrate (1.27 mmol) in DMF was added dropwise. The mixture was stirred at room temperature for 2.5 hours and then allowed to stand. The supernatant was removed, and the solid was immersed in 20 mL of DMF overnight. The supernatant was then removed and replaced with chloroform. The solid was immersed in 20 mL of chloroform overnight, and the solid was separated again. This washing procedure was repeated three times. The separated solid was then vacuum-dried at 150°C for 5 hours to obtain metal-organic structure 5-1 as a white solid.

[0094] [Example 5-2]~[Example 5-4] Except for using the compounds and solvents shown in Table 6 below, the same procedure as in Example 5-1 was followed to obtain metal-organic structures 5-2 to 5-4. The results are shown in Table 6.

[0095] [Table 6]

[0096] [Example 5-5] Compound number 1 (1 mmol) was dissolved in 13 mL of DMF, and triethylamine (0.28 mL) was added. A solution of zinc acetate dihydrate (2.54 mmol) in 17 mL of DMF was then added dropwise. The mixture was stirred at room temperature for 2.5 hours and allowed to stand. The supernatant was removed, and the solid was immersed in 20 mL of DMF overnight. The supernatant was then removed and replaced with chloroform. The solid was immersed in 20 mL of chloroform overnight, and the solid was separated again and the washing procedure was repeated three times. The separated solid was then vacuum-dried at 150°C for 5 hours to obtain metal-organic structure 5-5 as a white solid.

[0097] [Examples 5-6] to [Examples 5-8] Metal-organic structures 5-6 to 5-8 were obtained by following the same procedure as in Example 5-5, except that the compounds and solvents shown in Table 7 were used, and the temperature and reaction time were as shown in Table 7. The results are shown in Table 7.

[0098] [Table 7]

[0099] [Example 6-1] Compound No. 1 (0.3 mmol), cobalt nitrate hexahydrate (0.3 mmol), 5.6 mL of DMF, and 1.4 mL of ethanol were placed in an autoclave and sealed. The autoclave was heated at 100°C for 21 hours and then allowed to return to room temperature. The resulting solid was separated by centrifugation. The supernatant was removed and replaced with chloroform. The centrifuged solid was immersed in 20 mL of chloroform overnight, and this washing procedure was repeated three times. Subsequently, the centrifuged solid was vacuum-dried at 150°C for 5 hours to obtain metal-organic structure 6-1 as a gray solid.

[0100] [Example 6-2] Except for using compound number 6 instead of compound number 1, the same procedure as in Example 6-1 was followed to obtain metal-organic structure 6-2 as a pale red solid.

[0101] [Example 7-1] Compound No. 3 (0.4 mmol), nickel nitrate hexahydrate (0.8 mmol), 9 mL of DMF, and 1 mL of water were heated at 100°C for 16 hours and then allowed to return to room temperature. The resulting solid was filtered, and the filtrate was washed with DMF. The solid was immersed overnight in 20 mL of DMF, filtered, washed with chloroform, immersed overnight in 20 mL of chloroform, and filtered again. The solid was then vacuum-dried at 150°C for 5 hours to obtain metal-organic structure 7-1 as a brown solid.

[0102] [Example 7-2] Except for using cobalt nitrate hexahydrate instead of nickel nitrate hexahydrate, the same procedure as in Example 7-1 was followed to obtain metal-organic structure 7-2 as a brown solid.

[0103] [Example 7-3] Except for using compound number 4, THF / water (18 ml / 2 ml) as the solvent, and a reaction time of 48 hours, the procedure was the same as in Example 7-1, and solid-liquid separation was performed by centrifugation to obtain metal-organic structure 7-3 as a pale green solid.

[0104] [Example 8-1] Compound No. 3 (0.5 mmol), magnesium nitrate hexahydrate (1.0 mmol), 7 mL of THF, 3 mL of water, and 2 mL of 1N NaOH aqueous solution were heated at 100°C for 24 hours and then allowed to return to room temperature. The resulting solid was filtered, and the filtrate was washed with DMF. The solid was immersed overnight in 20 mL of DMF, filtered, washed with chloroform, immersed overnight in 20 mL of chloroform, and filtered again. The solid was then vacuum-dried at 150°C for 5 hours to obtain metal-organic structure 8-1 as a brown solid.

[0105] [Example 9-1] Compound No. 5 (0.84 mmol), copper hemi-pentahydrate (1.5 mmol), 5 mL of ethanol, and 5 mL of water were stirred at room temperature for 5 minutes. The mixture was heated at 140°C for 24 hours and then allowed to return to room temperature. The reaction product was centrifuged, and the resulting solid was washed with DMF. The centrifuged solid was washed with chloroform, immersed in 20 mL of chloroform overnight, and the solid was centrifuged again. The resulting solid was vacuum-dried at 150°C for 5 hours to obtain metal-organic structure 9-1 as a blue powder.

[0106] [Example 10-1] Compound No. 1 (118.3 mg, 0.60 mmol), zirconium tetrachloride (140.1 mg, 0.60 mmol), N,N-dimethylformamide (DMF) (8 mL), water (130 mg, 12 eq.), and acetic acid (1.803 g, 30 eq.) were placed in a screw-cap vial and sonicated. The vial was then sealed and heated at 120°C for 24 hours. After cooling to room temperature, the mixture was centrifuged and decanted to obtain a solid. DMF was added to the solid, and the centrifugation and decantation process was repeated three times. The solvent was changed to acetone, and the same procedure was repeated three times. After washing the solid, it was immersed in acetone for 24 hours. After centrifugation and decantation, the solid was vacuum-dried at 150°C for approximately 6 hours to obtain metal-organic structure 10-1 (159.1 mg) as an off-white powder.

[0107] [Examples 10-2 to 10-5] Except for using the compounds shown in Table 8 and carrying out the reaction under the reaction conditions shown in Table 8, the same procedure as in Example 10-1 was followed to obtain metal-organic structures 10-2 to 10-5. The results are shown in Table 8.

[0108] [Table 8]

[0109] [Example 10-6] Compound No. 6 (112.4 mg, 0.50 mmol), cobalt nitrate hexahydrate (145.8 mg, 0.50 mmol), and isonicotinic acid (62.1 mg, 0.5 mmol) were dissolved in 5 mL of N,N-dimethylformamide (DMF) and placed in a screw-cap vial, which was then sonicated. After sealing, the vial was heated at 120°C for 26 hours. After cooling to room temperature, the mixture was centrifuged and decanted to obtain a solid. DMF was added to the solid, and the centrifugation and decantation process was repeated three times. The solvent was changed to chloroform, and the same procedure was repeated three times. After washing the solid, it was immersed in chloroform for 24 hours. After centrifugation and decantation, the solid was vacuum-dried at 150°C for about 6 hours to obtain the metal-organic structure 10-6 (123.5 mg) as a purple powder.

[0110] [Example 10-7] The procedure was carried out in the same manner as in Example 10-6, except that the reaction temperature was set to 90°C, and metal-organic structure 10-7 was obtained as a purple powder.

[0111] [Example 10-8] Compound No. 1 (78.8 mg, 0.40 mmol) and copper nitrate trihydrate (96.7 mg, 0.40 mmol) were dissolved in 8 mL of N,N-dimethylformamide (DMF) and placed in a screw-cap vial, which was then sonicated. The vial was then sealed and heated at 120°C for 24 hours. After cooling to room temperature, the mixture was centrifuged and decanted to obtain a solid. DMF was added to the solid, and the centrifugation and decantation process was repeated three times. The solvent was changed to chloroform, and the same procedure was repeated three times. After washing the solid, it was immersed in chloroform for 24 hours. After centrifugation and decantation, the solid was vacuum-dried at 150°C for about 6 hours to obtain the metal-organic structure 10-8 (23.4 mg) as a dark green powder.

[0112] [Examples 10-9 to 10-10] Except for using the compounds shown in Table 9 and carrying out the reaction under the reaction conditions shown in Table 9, the same procedure as in Example 10-8 was followed to obtain metal-organic structures 10-9 to 10-10. The results are shown in Table 9.

[0113]

Table 9

[0114] [Example 10 - 11] The compound of Compound No. 1 (78.8 mg, 0.40 mmol) and nickel nitrate hexahydrate (233.2 mg, 0.80 mmol) were dissolved in 9 mL of THF and 1 mL of water, placed in an autoclave, and heated at 100 °C for 48 hours. After cooling to room temperature, centrifuged, and decanted to obtain a solid. DMF was added to the solid, centrifuged, and the decantation operation was repeated 3 times. The solvent was changed to chloroform, the same operation was repeated 3 times, and after washing the solid, it was immersed in chloroform for 24 hours. After centrifugation and decantation, the solid was vacuum dried at 150 °C for about 6 hours to obtain Metal - Organic Framework 10 - 11 (47.9 mg) as a yellow - green powder.

[0115] [Example 10 - 12] The same operations as in Example 10 - 11 were carried out except that the compound of Compound No. 6 was used instead of the compound of Compound No. 1, and Metal - Organic Framework 10 - 12 was obtained as a light - green powder.

[0116] [Example 11] (BET Specific Surface Area Measurement and Hydrogen Storage Capacity Measurement) For a part of the obtained metal - organic frameworks, the BET specific surface area and the hydrogen storage capacity at a temperature of 77 K - atmospheric pressure were measured. The measurement of the BET specific surface area and the hydrogen storage capacity at a temperature of 77 K - atmospheric pressure was carried out using a gas adsorption measurement device Tristar - II (manufactured by Micromeritics). The BET specific surface area was calculated by the following method. About 50 mg of the metal - organic framework was placed inside a glass cell. The inside of the glass cell was evacuated to a vacuum at a temperature of 135 °C and dried for 6 hours. The glass cell was attached to the gas adsorption measurement device and immersed in a constant - temperature bath containing liquid nitrogen. The pressure of nitrogen contained in the glass cell was gradually increased. When the pressure of nitrogen introduced into the glass cell reached 1.0×10 5Measurements were continued until the value reached Pa. The amount of hydrogen stored at a temperature of 77K and atmospheric pressure was calculated using the following method. After measuring nitrogen, the gas type was changed to hydrogen and measurements were taken. The pressure of the hydrogen contained in the glass cell was gradually increased. The pressure of the hydrogen introduced into the glass cell was 1.0 × 10⁻⁶. 5 Measurements were continued until the value reached Pa. The results of the measured BET specific surface area are shown in Table 10. Table 11 shows the amount of hydrogen stored at a measured temperature of 77K and atmospheric pressure.

[0117] [Table 10] JPEG2026074203000021.jpg51149

[0118] [Table 11]

[0119] (Measurement of carbon dioxide adsorption) For the obtained metal-organic structures 3-3, the amount of carbon dioxide stored was measured at a temperature of 273K and atmospheric pressure, and at a temperature of 298K and atmospheric pressure. The amount of carbon dioxide stored was measured using the Tristar-II gas adsorption analyzer (manufactured by Micromeritics). Approximately 50 mg of metal-organic structure 3-3 was placed inside a glass cell. The inside of the glass cell was reduced to a vacuum at a temperature of 135°C and dried for 6 hours. The glass cell was mounted on a gas adsorption amount measuring device and immersed in a constant temperature bath adjusted to a temperature of 273K or 298K. The pressure of carbon dioxide contained in the glass cell was gradually increased. The pressure of carbon dioxide introduced into the inside of the glass cell reached 1.0 × 10⁻⁶. 5 Measurements were continued until the reading reached Pa. The results of the measured carbon dioxide storage amount are shown in Table 12.

[0120] [Table 12]

[0121] (Heat of carbon dioxide adsorption) Based on the carbon dioxide adsorption experiments at different temperatures described above, the heat of carbon dioxide adsorption of organometallic structure 3-3 was calculated. Using the software included with Tristar-II, the calculation yielded 31 kJ·mol. -1 That was the case.

[0122] (Selectivity of carbon dioxide adsorption) The selectivity of organometallic structure 3-3 for carbon dioxide adsorption at 298K was estimated using the ideal adsorption solution method (IAST method). The carbon dioxide and nitrogen adsorption isotherms of 3-3 at 298K were fitted using the dual-site Langmuir-Freundlich equation, and the selectivity was calculated based on the ideal adsorption solution method. As a result, it was shown that organometallic structure 3-3 adsorbs 39 times more carbon dioxide than nitrogen at 298K.

[0123] (X-ray structural analysis) The metal-organic structure 1-24 obtained in Example 1-24 was subjected to X-ray structural analysis under the measurement conditions shown below. [Measurement conditions] A single colorless, transparent crystal of the metal-organic structure 1-24 obtained in Example 1-24, measuring 0.01 × 0.01 × 0.01 mm, was placed on a micromount, and diffraction experiments were performed using a single-crystal X-ray analyzer (D8 VENTURE, Bruker). The structure was determined by analyzing the diffraction data obtained by irradiating the single crystal with X-rays at a wavelength of 0.78192 Å. The results are shown in Table 13.

[0124] [Table 13]

[0125] The metal-organic structure 3-1 obtained in Example 3-1 was subjected to X-ray structural analysis under the same conditions as the measurements described above. The results are shown in Table 14.

[0126] [Table 14]

[0127] The metal-organic structure 3-4 obtained in Example 3-4 was subjected to X-ray structural analysis under the same conditions as the measurements described above. The results are shown in Table 15.

[0128] [Table 15] [Industrial applicability]

[0129] The gas storage material of the present invention can store gases such as hydrogen, carbon dioxide, methane, and acetylene at a practical level. As a result, for example, the use of hydrogen will become easier in preparation for the arrival of a hydrogen-based society, and carbon dioxide, a greenhouse gas, can be efficiently sequestrated.

Claims

1. A gas storage material containing a metal-organic structure formed by bonding at least one polyvalent metal ion selected from Zn, Co, Ni, Cu, Zr, and Mg with at least one compound selected from those represented by the following formulas (1) to (2), wherein the gas is hydrogen or carbon dioxide. 【Chemistry 1】

2. A gas storage method comprising the step of bringing hydrogen gas or carbon dioxide gas into contact with a gas storage material described in claim 1, thereby adsorbing or storing the hydrogen gas or carbon dioxide gas inside the gas storage material.

3. A storage tank for hydrogen gas or carbon dioxide gas, filled with the gas storage material described in claim 1.

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