A mixed-ligand metal-organic cage material, its preparation method and application

Abstract

This invention discloses a mixed-ligand metal-organic cage material, its preparation method, and its application, belonging to the field of metal-organic cage material synthesis technology. The structural formula of the mixed-ligand metal-organic cage material is: [Zn8(L 1 )2(L n )4(6-R-Py-2-CHO) 24 (NTf2) 16 Wherein, Py is pyridine; NTf2 ‑ As a counterion (bis(trifluoromethanesulfonyl)imide anion); L 1 L n The Zn atoms are different organic ligands; each Zn atom is linked to six N atoms via coordinate bonds. The mixed-ligand metal-organic cage material provided by this invention can catalyze the condensation cyclization reaction of o-aminobenzamide and aromatic aldehydes under heating conditions of 40°C, and has the advantages of wide substrate applicability, cycle stability, recyclability, and fast reaction rate.

Description

Technical Field

[0001] This invention belongs to the field of metal-organic cage material synthesis technology, specifically relating to a mixed-ligand metal-organic cage material, its preparation method, and its application. Background Technology

[0002] Metal-organic cages (MOCs), also known as metal-organic polyhedrons (MOPs) or coordination cages, are a class of discrete supramolecular coordination compounds with well-defined geometric configurations, specific structures, and tunable cavities (Chakrabarty R, Stang P J., et al. Chemical reviews 111.11 (2011): 6810-6918.). MOCs are assembled from metal ions and organic linkers through coordination bonds, and can generally be constructed through directional assembly or self-assembly of secondary components. Common shapes of MOCs include polyhedra, prisms, and helices. Among these, polyhedral MOCs are the most common, such as tetrahedral, hexahedral, octahedral, and dodecahedral MOCs. Due to the tunability of their cavity microenvironment and the properties derived from their specific geometric structures, MOCs have attracted widespread attention from researchers in recent years. The confined cavity structure of metal-organic cages allows them to generate rich host-guest interactions with guest molecules, thereby altering the physicochemical properties of the complex to varying degrees. Therefore, these supramolecular materials have potential applications in molecular recognition sensing, luminescent materials, catalysis, and host-guest chemistry.

[0003] Most metal-organic cages currently consist of a single ligand and have a highly symmetric structure, such as tetrahedral, cubic, and octahedral cages. These highly symmetric metal-organic cages tend to bind isotropic and highly symmetric guests (Greenfield JL, Nitschke J R. Accounts of Chemical Research 55.3 (2022):391-401.). However, some guests, such as biomolecules and natural products, have low symmetry and anisotropy. By reducing the symmetry of the metal-organic cage, the distribution of binding sites in the confined microenvironment can be modulated, which is beneficial to improving the binding ability of the host to low-symmetry and anisotropic guests.

[0004] An effective strategy to reduce the symmetry of metal-organic cages is to construct heteroligand metal-organic cages. Heteroligand metal-organic cages are metal-organic cage-like structures composed of two or more organic ligands and metal ions (Espinosa CF, Nitschke J R., et al. Journal of the American Chemical Society 145.18 (2023):9965-9969.), which is, in principle, an entropy-favorable process. A relatively effective method is to select two organic ligands with matching shapes and side lengths to construct heteroligand metal-organic cages (McTernan CT, Nitschke J R., et al. ChemicalReviews 122.11 (2022): 10393-10437.).

[0005] In the synthesis of heteroligand metal-organic cages, side reactions of single-ligand metal-organic cages often occur. Ensuring the selective formation of mixed-component structures and preventing the formation of single-component structures, ultimately obtaining a single target structure rather than a difficult-to-handle mixture, is challenging. Improving the selectivity and yield of heteroligand metal-organic cages through meticulous control of reaction conditions and effective modification of ligands is a crucial problem that urgently needs to be solved. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention proposes a mixed-ligand metal-organic cage material, its preparation method, and its application.

[0007] To achieve the above objectives, the present invention provides the following technical solution: One of the technical solutions of this invention is to provide a mixed-ligand metal-organic cage material, the structural formula of which is: [Zn8(L 1 )2(L n )4(6-R-Py-2-CHO) 24 (NTf2) 16 Wherein, Py is pyridine; NTf2 - It is a bis(trifluoromethanesulfonyl)imide anion; L 1 The structural formula is n = 2 to 5 integers; each Zn is connected to 6 N via coordinate bonds; When n=2, L 2 The structural formula is R is H; When n=3, L 3 The structural formula is R is a methyl group; When n=4, L 4 The structural formula is R is a methyl group; When n=5, L 5 The structural formula is R stands for methyl.

[0008] When n=2, the mixed-ligand metal-organic cage material belongs to the tetragonal crystal system, with space group . I 4; The unit cell parameters are: a=b=22.9036Å, c=45.9555Å, α=β=γ=90°, V=24107.1Å 3 The mixed-ligand metal-organic cage material L 1 As the top and bottom surfaces, L 2 As four sides, the center of Zn(II) forms eight vertices, creating a cuboid structure, denoted as [Zn8(L...]. 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 .

[0009] The second technical solution of the present invention provides a method for preparing the above-mentioned mixed-ligand metal-organic cage material, comprising the following steps: L 1 L n Zinc bis(trifluoromethanesulfonyl)imide and 6-R-pyridine-2-carboxaldehyde are mixed in a solvent and stirred to obtain a mixed-ligand metal-organic cage material; when n=2, R in 6-R-pyridine-2-carboxaldehyde is H; when n=3~5, R in 6-R-pyridine-2-carboxaldehyde is methyl.

[0010] Preferably, the L 1 L n The molar ratio of zinc bis(trifluoromethanesulfonyl)imide and 6-R-pyridine-2-carboxaldehyde is 2:4:8:24.

[0011] Preferably, the solvent is acetonitrile.

[0012] Preferably, the temperature of the stirring reaction is 70°C.

[0013] Preferably, the reaction further includes separation and purification steps after the stirring reaction is completed.

[0014] More preferably, the separation step includes: concentrating the reaction system and then adding a poor solvent to the mixed ligand metal-organic cage material to precipitate the mixed ligand metal-organic cage material.

[0015] More preferably, the purification step includes: washing and drying the precipitated mixed-ligand metal-organic cage material to obtain purified mixed-ligand metal-organic cage material.

[0016] The third technical solution of the present invention provides an application of the above-mentioned mixed-ligand metal-organic cage material in the catalytic condensation cyclization reaction of o-aminobenzamide and aromatic aldehyde.

[0017] Preferably, the mixed-ligand metal-organic cage material catalyzes a condensation cyclization reaction between 2-aminobenzamide and p-methylbenzaldehyde, 2-aminobenzamide and 4-isopropylbenzaldehyde, 2-aminobenzamide and 3,5-dimethylbenzaldehyde, 2-aminobenzamide and p-tert-butylbenzaldehyde, 2-aminobenzamide and p-fluorobenzaldehyde, 2-aminobenzamide and p-nitrobenzaldehyde, 2-amino-4-chlorobenzamide and p-fluorobenzaldehyde, 2-amino-4-methylbenzamide and p-fluorobenzaldehyde, 2-aminobenzamide and 1-naphthaldehyde, 2-aminobenzamide and p-phenylbenzaldehyde, 2-aminobenzamide and 2'-methyl-biphenyl-4-carboxaldehyde, or 2-aminobenzamide and 9-anthracarboxaldehyde under a heating condition of 40°C.

[0018] The beneficial technical effects of the present invention are as follows: The mixed-ligand metal-organic cage material [Zn8(L] provided by this invention 1 )2(L n )4(6-R-Py-2-CHO) 24 (NTf2) 16 It can catalyze the condensation cyclization reaction of o-aminobenzamide and aromatic aldehydes under heating conditions of 40℃, and has the advantages of wide substrate applicability, cycle stability, recyclability and fast reaction rate. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 The mixed-ligand metal-organic cage [Zn8(L] in this invention 1 )2(L n )4(6-R-Py-2-CHO) 24 (NTf2) 16 A schematic diagram of the synthesis.

[0021] Figure 2 The image shows the hydrogen nuclear magnetic resonance spectrum of compound 1-1 in Example 1.

[0022] Figure 3 The above are the 1H NMR spectra of compounds 1-2 in Example 2.

[0023] Figure 4 The image shows the hydrogen nuclear magnetic resonance spectrum of compound 2-1 in Example 3.

[0024] Figure 5 The image shows the hydrogen nuclear magnetic resonance spectrum of compound 2-2 in Example 4.

[0025] Figure 6 The image shows the hydrogen nuclear magnetic resonance spectrum of compound 3-1 in Example 5.

[0026] Figure 7 The image shows the hydrogen nuclear magnetic resonance spectrum of compound 3-2 in Example 6.

[0027] Figure 8 The image shows the hydrogen nuclear magnetic resonance spectrum of compound 3-3 in Example 7.

[0028] Figure 9 The mixed-ligand metal-organic cage material [Zn8(L] in Example 8] 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum and mass spectrum are shown, where a is the 1H NMR spectrum and b is the mass spectrum.

[0029] Figure 10 The mixed-ligand metal-organic cage material [Zn8(L] in Example 9] 1 )2(L 3 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum and mass spectrum are shown, where a is the 1H NMR spectrum and b is the mass spectrum.

[0030] Figure 11 The mixed-ligand metal-organic cage material [Zn8(L] in Example 10] 1 )2(L 4 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum and mass spectrum are shown, where a is the 1H NMR spectrum and b is the mass spectrum.

[0031] Figure 12 The mixed-ligand metal-organic cage material [Zn8(L] in Example 11] 1 )2(L 5 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum and mass spectrum are shown, where a is the 1H NMR spectrum and b is the mass spectrum.

[0032] Figure 13 For the mixed-ligand metal-organic cage material [Zn8(L)] in Test Example 1 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum of the condensation cyclization product formed by the reaction of 2-aminobenzamide and p-methylbenzaldehyde.

[0033] Figure 14 For the mixed-ligand metal-organic cage material [Zn8(L)] in Test Example 2 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum of the condensation cyclization product formed by the reaction of 2-aminobenzamide and 4-isopropylbenzaldehyde.

[0034] Figure 15 For testing the mixed-ligand metal-organic cage material [Zn8(L)] in Example 3 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum of the condensation cyclization product formed by the reaction of 2-aminobenzamide and 3,5-dimethylbenzaldehyde.

[0035] Figure 16 For testing the mixed-ligand metal-organic cage material [Zn8(L)] in Example 4 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum of the condensation cyclization product formed by the reaction of 2-aminobenzamide with p-tert-butylbenzaldehyde.

[0036] Figure 17 For testing the mixed-ligand metal-organic cage material [Zn8(L)] in Example 5 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum of the condensation cyclization product formed by the reaction of 2-aminobenzamide and p-fluorobenzaldehyde.

[0037] Figure 18 For testing the mixed-ligand metal-organic cage material [Zn8(L)] in Example 6 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16The 1H NMR spectrum of the condensation cyclization product formed by the reaction of 2-aminobenzamide and p-nitrobenzaldehyde.

[0038] Figure 19 For testing the mixed-ligand metal-organic cage material [Zn8(L)] in Example 7 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum of the condensation cyclization product formed by the reaction of 2-amino-4-chlorobenzamide with p-fluorobenzaldehyde.

[0039] Figure 20 To test the mixed-ligand metal-organic cage material [Zn8(L] in Example 8] 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum of the condensation cyclization product formed by the reaction of 2-amino-4-methylbenzamide and p-fluorobenzaldehyde.

[0040] Figure 21 To test the mixed-ligand metal-organic cage material [Zn8(L)] in Example 9 1 )2(L 5 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum of the condensation cyclization product formed by the reaction of 2-aminobenzamide and 1-naphthaldehyde.

[0041] Figure 22 For the mixed-ligand metal-organic cage material [Zn8(L)] in Test Example 10 1 )2(L 5 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum of the condensation cyclization product formed by the reaction of 2-aminobenzamide and p-phenylbenzaldehyde.

[0042] Figure 23 For the mixed-ligand metal-organic cage material [Zn8(L)] in Test Example 11 1 )2(L 5 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The 1H NMR spectrum of the condensation cyclization product formed by the reaction of 2-aminobenzamide with 2'-methyl-biphenyl-4-carboxaldehyde.

[0043] Figure 24The 1H NMR spectrum of the mixed-ligand metal-organic cage material [Zn8(L1)2(L5)4(6-H-Py-2-CHO)24](NTf2)16 in Test Example 12 catalyzes the formation of a condensation cyclization product from 2-aminobenzamide and 9-anthracene carboxaldehyde.

[0044] Figure 25 The 1H NMR spectrum of the mixed-ligand metal-organic cage material [Zn8(L1)2(L3)4(6-H-Py-2-CHO)24(NTf2)16 catalyzing the condensation cyclization product of 2-aminobenzamide and p-fluorobenzaldehyde is shown in Test Example 13.

[0045] Figure 26 The 1H NMR spectrum of the mixed-ligand metal-organic cage material [Zn8(L1)2(L4)4(6-H-Py-2-CHO)24(NTf2)16 catalyzing the condensation cyclization product of 2-aminobenzamide and p-fluorobenzaldehyde is shown in Test Example 14.

[0046] Figure 27 The 1H NMR spectrum of the mixed-ligand metal-organic cage material [Zn8(L1)2(L5)4(6-H-Py-2-CHO)24(NTf2)16 catalyzing the condensation cyclization product of 2-aminobenzamide and p-fluorobenzaldehyde is shown in Test Example 15. Detailed Implementation

[0047] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.

[0048] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.

[0049] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, are also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0050] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar to or equivalent to those described herein may be used in the implementation or testing of this invention.

[0051] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0052] Unless otherwise specified, the room temperature in this invention is 25±2℃.

[0053] All raw materials used in the embodiments of this invention were obtained through commercial purchase.

[0054] In this invention, the mixed-ligand metal-organic cage [Zn8(L 1 )2(L n )4(6-R-Py-2-CHO) 24 (NTf2) 16 See the schematic diagram of the synthesis. Figure 1 .

[0055] Example 1 The synthetic route for the preparation of compound 1-1 is as follows: Synthesis and characterization of tetra-tert-butyltetracarboxylate ([2,2'-bis(1,3-dithiomethylene)]-4,4',5,5'-tetramethyltetraphenyl-4,1-diyl) (1-1): First, palladium acetate (0.37 mmol), cesium carbonate (7.4 mmol), and tri-tert-butyltetrafluoroborate (1.11 mmol) were added to a dry two-necked round-bottom flask equipped with a stir bar, and the flask was evacuated and filled with nitrogen three times. Then, anhydrous tetrahydrofuran (10 mL) was added to the flask, and the suspension was heated under reflux for 10 minutes. Afterwards, a mixture containing compound A (1.23 mmol) and N-(tert-butyloxycarbonyl)-4-bromoaniline (6.15 mmol, structural formula: [Insert structural formula here]) was added. A 10 mL solution of anhydrous tetrahydrofuran was prepared. The resulting mixture was refluxed overnight with stirring, then cooled to room temperature and filtered. The filtrate was concentrated under reduced pressure, the residue was thoroughly washed with hexane, and then further purified by recrystallization from chloroform to give a pink solid compound 1-1 (280 mg, 0.29 mmol, yield 24%). Its 1H NMR spectrum is shown below. Figure 2 As shown, the data demonstrate the successful synthesis of compound 1-1 (tetra-tert-butyltetracarboxylate ([2,2'-bis(1,3-dithiomethylene)]-4,4',5,5'-tetramethyltetraphenyl-4,1-diyl)).

[0056] Example 2 Compounds 1-2 (organic ligand L) 3 The preparation of ) is carried out via the following synthetic route: Synthesis and characterization of 4,4',4'',4'''-([2,2'-bis(1,3-dithioheteropropyl)]-4,4',5,5'-tetraethylenedimethyl)tetraphenylamine (1-2): Compound 1-1 (0.253 mmol) was dispersed in a Schlenk flask containing 10 mL of dichloromethane under nitrogen protection, followed by dropwise addition of trifluoroacetic acid (18.7 mmol). The reaction mixture was stirred at room temperature for 3 hours, and then the reaction solution was poured into 80 mL of sodium hydroxide solution. The resulting orange solid was collected by filtration, washed several times with water and methanol, and dried under vacuum to give the orange solid compound 1-2 (134 mg, 0.24 mmol, yield 93%). Its 1H NMR spectrum is shown below. Figure 3 The data shown demonstrate the successful synthesis of compound 1-2 (4,4',4'',4'''-([2,2'-bis(1,3-dithioheterocyclopropenyl)]-4,4',5,5'-tetramethylene)tetraphenylamine).

[0057] Example 3 The synthetic route for the preparation of compound 2-1 is as follows: Synthesis and characterization of 2,3,13,14-tetrabromo-6,7,9,10,17,18,20,21-octahydrodibenzo[b,k][1,4,7,10,13,16]hexaoxane (2-1): Liquid bromine (77.6 mmol) was added to a mixture of compound B (2.7 mmol), acetic acid (30 mL), and water (25 mL) in a round-bottom flask, and the resulting mixture was heated to reflux for 12 hours. The mother liquor was then cooled to room temperature, and the resulting white precipitate was collected by vacuum filtration and washed with diethyl ether (20 mL). Recrystallization in chloroform gave a white solid compound 2-1 (1415 mg, 2.1 mmol, yield 78%). Its 1H NMR spectrum is shown below. Figure 4 As shown, the data demonstrate the successful synthesis of compound 2-1 (2,3,13,14-tetrabromo-6,7,9,10,17,18,20,21-octahydrodibenzo[b,k][1,4,7,10,13,16]hexaoxane).

[0058] Example 4 Compound 2-2 (organic ligand L) 4 The preparation of ) is carried out via the following synthetic route: Synthesis and characterization of 4,4',4'',4'''-(6,7,9,10,17,18,20,21-octahydrodibenzo[b,k][1,4,7,10,13,16]hexaoxane-2,3,13,14-tetrayl)tetraphenylamine (2-2): In a Sürenk flask, compound 2-1 (4.6 mmol) and 4-aminophenylboronic acid pinacol ester (23 mmol, structural formula: Cesium carbonate (23 mmol) and cesium carbonate (1,4-dioxane) were dissolved in a mixed solution of 1,4-dioxane (100 mL) and water (25 mL). The mixture was heated and stirred at 90 °C for 2 days. After the reaction was completed, the mixture was filtered to obtain a grayish-white solid compound 2-2 (2665 mg, 3.7 mmol, yield 80%). Its 1H NMR spectrum is shown below. Figure 5 The data shown demonstrate the successful synthesis of compound 2-2 (4,4',4'',4'''-(6,7,9,10,17,18,20,21-octahydrodibenzo[b,k][1,4,7,10,13,16]hexaoxane-2,3,13,14-tetramethyl)tetraphenylamine).

[0059] Example 5 The synthetic route for the preparation of compound 3-1 is as follows: Synthesis and characterization of 1,2-bis(4-nitrophenyl)ethane-1,2-dione (3-1): A mixture of compound C (0.373 mmol), palladium chloride (0.04 mmol), and dimethyl sulfoxide (4 mL) was stirred at 140 °C for 12 h. After the reaction, the organic phase was extracted with water and dichloromethane, collected, concentrated under vacuum, and subjected to column chromatography (petroleum ether:dichloromethane = 1:1, v / v) to give a yellow solid compound 3-1 (80 mg, 0.268 mmol, yield 72%). Its 1H NMR spectrum is shown below. Figure 6 The data shown demonstrate the successful synthesis of compound 3-1 (1,2-bis(4-nitrophenyl)ethane-1,2-dione).

[0060] Example 6 The synthetic route for the preparation of compound 3-2 is as follows: Synthesis and characterization of 2,3,7,8-tetra(4-nitrophenyl)pyrazino[2,3-g]quinoxaline (3-2): 1,2,4,5-phenyltetramine (0.0833 mmol, structural formula: A mixture of compound 3-1 (0.1665 mmol) and acetic acid (10 mL) was added to a round-bottom flask. The mixture was stirred at 120 °C for 24 hours. After cooling to room temperature, the organic phase was extracted with water and dichloromethane. The organic phase was dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. Column chromatography (petroleum ether:dichloromethane = 2:1, v / v) gave a pale yellow solid, compound 3-2 (41 mg, 0.0616 mmol, yield 74%). Its 1H NMR spectrum is shown below. Figure 7 The data shown demonstrate the successful synthesis of compound 3-2 (2,3,7,8-tetra(4-nitrophenyl)pyrazino[2,3-g]quinoxaline).

[0061] Example 7 Compound 3-3 (organic ligand L) 5 The preparation of ) is carried out via the following synthetic route: Synthesis and characterization of 4,4',4'',4'''-(pyrazino[2,3-g]quinoxaline-2,3,7,8-tetrayl)tetraphenylamine (3-3): A mixture of compound 3-2 (0.0375 mmol), palladium on carbon (0.169 mmol), hydrazine hydrate (4.35 mmol), and ethanol (10 mL) was added to a round-bottom flask. The mixture was stirred at 80 °C for 12 hours. After cooling to room temperature, the mixture was filtered and the solid was collected. The solid was then washed with ethyl acetate, and the washings were collected and concentrated under vacuum. Finally, the solid was dried to give a reddish-brown solid, compound 3-3 (14 mg, 0.0255 mmol, yield 68%). Its 1H NMR spectrum is shown below. Figure 8 The data shown illustrate the successful synthesis of compound 3-3 (4,4',4'',4'''-(pyrazino[2,3-g]quinoxaline-2,3,7,8-tetramethyl)tetraphenylamine).

[0062] Example 8 Mixed-ligand metal-organic cage material [Zn8(L 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 Preparation: L 1 (0.04 mmol, 1 eq.), L 2(0.08 mmol, 2 eq.), Zn(NTf2)2 (0.16 mmol, 4 eq.) and pyridine-2-carboxaldehyde (0.48 mmol, 12 eq.) were mixed in MeCN (20 mL) and stirred at 70 °C for 8 hours. After the reaction was completed, the solution was concentrated to 1 mL, and diethyl ether (50 mL) was added. The precipitate was collected by centrifugation and washed with ethyl acetate (2 × 50 mL). After drying, a yellow solid [Zn8(L)] was obtained. 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 (172 mg, 0.0177 mmol, yield 88%), [Zn8(L 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The proton NMR spectrum (a) and mass spectrum (b) are shown below. Figure 9 As shown, the data description is [Zn8(L 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 Successful synthesis.

[0063] Example 9 Mixed-ligand metal-organic cage material [Zn8(L 1 )2(L 3 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 Preparation: L 1 (0.02 mmol, 1 eq.), L 3 (0.04 mmol, 2 eq.) Zn(NTf2)2 (0.08 mmol, 4 eq.) and 6-methyl-2-formylpyridine (0.24 mmol, 12 eq.) were mixed in MeCN (10 mL) and stirred at 70 °C for 8 hours. After the reaction was completed, the solution was concentrated to 1 mL and diethyl ether (50 mL) was added. The precipitate was collected by centrifugation and washed with ethyl acetate (2 × 50 mL). After drying, a brown solid [Zn8(L)] was obtained. 1 )2(L 3 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 (97 mg, 0.0092 mmol, yield 92%), [Zn8(L 1 )2(L3 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 The proton NMR spectrum (a) and mass spectrum (b) are shown below. Figure 10 As shown, the data description is [Zn8(L 1 )2(L 3 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 Successful synthesis.

[0064] Example 10 Mixed-ligand metal-organic cage material [Zn8(L 1 )2(L 4 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 Preparation: L 1 (0.02 mmol, 1 eq.), L 4 (0.04 mmol, 2 eq.) Zn(NTf2)2 (0.08 mmol, 4 eq.) and 6-methyl-2-formylpyridine (0.24 mmol, 12 eq.) were mixed in MeCN (10 mL) and stirred at 70 °C for 8 hours. After the reaction was completed, the solution was concentrated to 1 mL and diethyl ether (50 mL) was added. The precipitate was collected by centrifugation and washed with ethyl acetate (2 × 50 mL). After drying, a brown solid [Zn8(L)] was obtained. 1 )2(L 4 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 (104 mg, 0.0093 mmol, yield 93%), [Zn8(L 1 )2(L 4 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 The proton NMR spectrum (a) and mass spectrum (b) are shown below. Figure 11 As shown, the data description is [Zn8(L 1 )2(L 4 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 Successful synthesis.

[0065] Example 11 Mixed-ligand metal-organic cage material [Zn8(L 1 )2(L 5)4(6-CH3-Py-2-CHO) 24 (NTf2) 16 Preparation: L 1 (0.01 mmol, 1 eq.), L 5 Zn(NTf2)2 (0.02 mmol, 2 eq.), Zn(NTf2)2 (0.04 mmol, 4 eq.) and 6-methyl-2-formylpyridine (0.12 mmol, 12 eq.) were mixed in MeCN (5 mL) and stirred at 70 °C for 8 hours. After the reaction was completed, the solution was concentrated to 1 mL and diethyl ether (50 mL) was added. The precipitate was collected by centrifugation and washed with ethyl acetate (2 × 50 mL). After drying, a reddish-brown solid [Zn8(L)] was obtained. 1 )2(L 5 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 (46 mg, 0.0044 mmol, yield 88%), [Zn8(L 1 )2(L 5 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 The proton NMR spectrum (a) and mass spectrum (b) are shown below. Figure 12 As shown, the data description is [Zn8(L 1 )2(L 5 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 Successful synthesis.

[0066] Single-crystal structure determination: Single-crystal samples of the complex with suitable dimensions (length, width, and height all around 0.22 mm) and no obvious cracks were selected. Data acquisition was performed using an XtaLab PRO MM007HF DW single-crystal diffractometer, employing Cu-Kα rays (λ = 1.54184 Å) as the light source and collecting diffraction data in ω-scan mode. Absorption correction was performed using a multi-scan method. Mixed-ligand metal-organic cage [Zn8(L...] 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16The test conditions were set at 100 K; diffraction data were analyzed using Olex2 software, where the positions of metal atoms and other non-hydrogen atoms were determined by the direct method. Subsequently, the coordinates of the remaining non-hydrogen atoms were determined using difference Fourier synthesis and least squares refinement methods, followed by anisotropic refinement. The positions of hydrogen atoms were obtained using the theoretical hydrogenation method. For guest molecules, the SQUEEZE module in the PLATON program was used for processing. [Zn8(L 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 The crystallographic data and refinement parameters are detailed in Table 1.

[0067] Table 1 Mixed-ligand metal-organic cage materials [Zn8(L 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 Single crystal structure parameters Test Example 1 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and p-methylbenzaldehyde.

[0068] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and p-methylbenzaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 80%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 13 As shown, the data indicates that 2-aminobenzamide reacts with p-methylbenzaldehyde to form a condensation cyclization product.

[0069] Test Example 2 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and 4-isopropylbenzaldehyde.

[0070] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and 4-isopropylbenzaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 88%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 14 As shown, the data indicates that 2-aminobenzamide reacts with 4-isopropylbenzaldehyde to form a condensation cyclization product.

[0071] Test Example 3 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and 3,5-dimethylbenzaldehyde.

[0072] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and 3,5-dimethylbenzaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 87%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 15 As shown, the data indicates that 2-aminobenzamide reacts with 3,5-dimethylbenzaldehyde to form a condensation cyclization product.

[0073] Test Example 4 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and p-tert-butylbenzaldehyde.

[0074] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and p-tert-butylbenzaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 87%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 16 As shown, the data indicates that 2-aminobenzamide reacts with p-tert-butylbenzaldehyde to form a condensation cyclization product.

[0075] Test Example 5 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and p-fluorobenzaldehyde.

[0076] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and p-fluorobenzaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 99%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 17 As shown, the data indicates that 2-aminobenzamide reacts with p-fluorobenzaldehyde to form a condensation cyclization product.

[0077] Test Example 6 Mixed-ligand metal-organic cage Zn8(L) 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and p-nitrobenzaldehyde.

[0078] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 2 )4(6-H-Py-2-CHO) 24(NTf2) 16 As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and p-nitrobenzaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 82%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 18 As shown, the data indicates that 2-aminobenzamide reacts with p-nitrobenzaldehyde to form a condensation cyclization product.

[0079] Test Example 7 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-amino-4-chlorobenzamide with p-fluorobenzaldehyde.

[0080] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 As a catalyst, 0.1 mol% of the catalyst, 2-amino-4-chlorobenzamide, and p-fluorobenzaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 60%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 19 As shown, the data indicates that 2-amino-4-chlorobenzamide reacts with p-fluorobenzaldehyde to form a condensation cyclization product.

[0081] Test Example 8 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-amino-4-methylbenzamide with p-fluorobenzaldehyde.

[0082] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 2 )4(6-H-Py-2-CHO) 24 (NTf2) 16As a catalyst, 0.1 mol% of the catalyst, 2-amino-4-methylbenzamide, and p-fluorobenzaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 75%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 20 As shown, the data indicates that 2-amino-4-methylbenzamide reacts with p-fluorobenzaldehyde to form a condensation cyclization product.

[0083] Test Example 9 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 5 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and 1-naphthaldehyde.

[0084] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 5 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and 1-naphthaldehyde were mixed and reacted for 14 hours under heating at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 90%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 21 As shown, the data indicates that 2-aminobenzamide reacts with 1-naphthaldehyde to form a condensation cyclization product.

[0085] Test Case 10 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 5 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and p-phenylbenzaldehyde.

[0086] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 5 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and p-phenylbenzaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 92%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 22 As shown, the data indicates that 2-aminobenzamide reacts with p-phenylbenzaldehyde to form a condensation cyclization product.

[0087] Test Example 11 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 5 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and 2'-methyl-biphenyl-4-carboxaldehyde.

[0088] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 5 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and 2'-methyl-biphenyl-4-carboxaldehyde were mixed and reacted at 40 °C for 14 hours. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 88%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 23 As shown, the data indicates that 2-aminobenzamide reacts with 2'-methyl-biphenyl-4-carboxaldehyde to form a condensation cyclization product.

[0089] Test Example 12 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 5 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and 9-anthracarboxaldehyde.

[0090] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 5 )4(6-CH3-Py-2-CHO) 24 (NTf2) 16As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and 9-anthracene carboxaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 59%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 24 As shown, the data indicates that 2-aminobenzamide reacts with 9-anthracene aldehyde to form a condensation cyclization product.

[0091] Test Example 13 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 3 )4(6-H-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and p-fluorobenzaldehyde.

[0092] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 3 )4(6-H-Py-2-CHO) 24 (NTf2) 16 As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and p-fluorobenzaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 88%. Its 1H NMR spectrum (characterized in deuterated DMSO) is shown below. Figure 25 As shown, the data indicates that 2-aminobenzamide reacts with p-fluorobenzaldehyde to form a condensation cyclization product.

[0093] Test Example 14 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 4 )4(6-H-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and p-fluorobenzaldehyde.

[0094] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 4 )4(6-H-Py-2-CHO) 24 (NTf2) 16As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and p-fluorobenzaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 87%. Its 1H NMR spectrum (characterized in deuterated acetonitrile) is shown below. Figure 26 As shown, the data indicates that 2-aminobenzamide reacts with p-fluorobenzaldehyde to form a condensation cyclization product.

[0095] Test Example 15 Mixed-ligand metal-organic cage [Zn8(L 1 )2(L 5 )4(6-H-Py-2-CHO) 24 (NTf2) 16 It is used to catalyze the condensation cyclization reaction of 2-aminobenzamide and p-fluorobenzaldehyde.

[0096] The metal-organic cage [Zn8(L], a mixture of ligands completely soluble in acetonitrile and toluene] 1 )2(L 5 )4(6-H-Py-2-CHO) 24 (NTf2) 16 As a catalyst, 0.1 mol% of the catalyst, 2-aminobenzamide, and p-fluorobenzaldehyde were mixed and reacted for 14 hours at 40 °C. The condensation cyclization product was obtained by column chromatography (petroleum ether:ethyl acetate = 1:1, v / v), with a separation yield of 81%. Its 1H NMR spectrum (characterized in deuterated chloroform) is shown below. Figure 27 As shown, the data indicates that 2-aminobenzamide reacts with p-fluorobenzaldehyde to form a condensation cyclization product.

[0097] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A mixed-ligand metal-organic cage material, characterized in that, The structural formula of the mixed-ligand metal-organic cage material is: [Zn8(L 1 )2(L n )4(6-R-Py-2-CHO) 24 (NTf2) 16 ; Where Py is pyridine; NTf2 - It is a bis(trifluoromethanesulfonyl)imide anion; L 1 The structural formula is n = 2 to 5 integers; each Zn is connected to 6 N via coordinate bonds; When n=2, L 2 The structural formula is R is H; When n=3, L 3 The structural formula is R is a methyl group; When n=4, L 4 The structural formula is R is a methyl group; When n=5, L 5 The structural formula is R stands for methyl.

2. A method for preparing the mixed-ligand metal-organic cage material according to claim 1, characterized in that, Includes the following steps: L 1 L n Zinc bis(trifluoromethanesulfonyl)imide and 6-R-pyridine-2-carboxaldehyde are mixed in a solvent and stirred to obtain a mixed-ligand metal-organic cage material; when n=2, R in 6-R-pyridine-2-carboxaldehyde is H; when n=3~5, R in 6-R-pyridine-2-carboxaldehyde is methyl.

3. The method for preparing the mixed-ligand metal-organic cage material according to claim 2, characterized in that, The L 1 L n The molar ratio of zinc bis(trifluoromethanesulfonyl)imide and 6-R-pyridine-2-carboxaldehyde is 2:4:8:

24.

4. The method for preparing the mixed-ligand metal-organic cage material according to claim 2, characterized in that, The solvent is acetonitrile.

5. The method for preparing the mixed-ligand metal-organic cage material according to claim 2, characterized in that, The temperature of the stirring reaction is 70°C.

6. The method for preparing the mixed-ligand metal-organic cage material according to claim 2, characterized in that, After the reaction is complete, separation and purification steps are also included.

7. The method for preparing the mixed-ligand metal-organic cage material according to claim 6, characterized in that, The separation step includes: concentrating the reaction system and adding a poor solvent for the mixed ligand metal-organic cage material to precipitate the mixed ligand metal-organic cage material.

8. The method for preparing the mixed-ligand metal-organic cage material according to claim 7, characterized in that, The purification step includes: washing and drying the precipitated mixed-ligand metal-organic cage material to obtain purified mixed-ligand metal-organic cage material.

9. The application of the mixed-ligand metal-organic cage material of claim 1 in the catalytic condensation cyclization reaction of anthranilamide and aromatic aldehyde.

10. The application according to claim 9, characterized in that, The mixed-ligand metal-organic cage material catalyzes the condensation cyclization reactions of 2-aminobenzamide with p-methylbenzaldehyde, 2-aminobenzamide with 4-isopropylbenzaldehyde, 2-aminobenzamide with 3,5-dimethylbenzaldehyde, 2-aminobenzamide with p-tert-butylbenzaldehyde, 2-aminobenzamide with p-fluorobenzaldehyde, 2-aminobenzamide with p-nitrobenzaldehyde, 2-amino-4-chlorobenzamide with p-fluorobenzaldehyde, 2-amino-4-methylbenzamide with p-fluorobenzaldehyde, 2-aminobenzamide with 1-naphthaldehyde, 2-aminobenzamide with p-phenylbenzaldehyde, 2-aminobenzamide with 2'-methyl-biphenyl-4-carboxaldehyde, or 2-aminobenzamide with 9-anthracarboxaldehyde under heating conditions at 40°C.

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