A two-dimensional metal organic layer based on multi-nitrogen ligand and preparation method and application thereof

Abstract

This invention discloses a two-dimensional metal-organic layer based on a multi-nitrogen ligand, its preparation method, and its application. The general structural formula of the two-dimensional metal-organic layer is shown in formula (Ⅰ), where N is nitrogen, M is selected from CH or N, and Y is selected from CO2(Zr(μ3-O)4(μ3-OH)4). 1 / 6 , CO2(Hf(μ3‑O)4(μ3‑OH)4) 1 / 6 ,Ph‑CO2(Zr(μ3‑O)4(μ3‑OH)4) 1 / 6 , Ph‑CO2(Hf(μ3‑O)4(μ3‑OH)4) 1 / 6 One or more of the following, where Ph is a benzene ring; the two-dimensional metal-organic layer based on polynitrogen ligands disclosed in this invention has a novel structure, can achieve efficient loading of biomacromolecules without significantly reducing their original biological activity; it can also be applied to photocatalytic olefin isomerization and enzyme-supported asymmetric hydrogenation reactions, exhibiting excellent catalytic activity.

Description

Technical Field

[0001] This invention relates to the technical field of materials chemistry, and in particular to a two-dimensional metal-organic layer based on polynitrogen ligands, its preparation method, and its application. Background Technology

[0002] While biomacromolecules possess powerful functions, they often suffer from poor stability, susceptibility to environmental conditions, and low bioavailability. Loading these macromolecules onto specific carrier materials can significantly improve their stability, extend their in vitro and in vivo interaction time, enhance their biocompatibility and targeting capabilities, thereby expanding their application range and increasing their activity. Metal-organic frameworks (MOFs) possess highly customizable pore structures, large specific surface areas, and tunable chemical and physical properties, making them excellent materials for loading biomacromolecules. However, limited by the stability of their structure and the rigidity of their ligands, the pores of framework materials are generally only a few or tens of angstroms. Biomacromolecules, on the other hand, often reach sizes exceeding ten nanometers, far exceeding the inner diameter of these pores. Even in biomineralization schemes, excessively large proteins often significantly affect the mineralization process. Therefore, current research is often limited to smaller proteins such as lipases and proteases.

[0003] Two-dimensional metal-organic layers (MOLs) are two-dimensional analogs of metal-organic frameworks, characterized by high aspect ratios and thicknesses as thin as a single layer. Their surface adsorption is not limited by the size of the adsorbed material and can significantly reduce mass transfer resistance during encapsulation. Therefore, for large biomolecules, protein loading via MOL surface adsorption is a more feasible loading method. However, in practice, MOL loading often leads to reduced protein activity. A key reason is that ligands often possess strong hydrophobicity, causing conformational changes upon contact with the protein surface and consequently reducing its catalytic activity. Summary of the Invention

[0004] To address the aforementioned problems in existing technologies, this invention discloses a novel two-dimensional metal-organic layer based on multi-nitrogen ligands. This layer can achieve efficient loading of biomolecules without significantly reducing their original biological activity. Furthermore, it can be applied to photocatalytic olefin isomerization and enzyme-supported asymmetric hydrogenation reactions, exhibiting excellent catalytic activity.

[0005] The specific technical solution is as follows:

[0006] A two-dimensional metal-organic layer based on a polynitrogen ligand has the following general structural formula (Ⅰ):

[0007]

[0008] In the formula, N is nitrogen, and M is selected from CH or N;

[0009] Y is selected from CO2(Zr(μ3-O)4(μ3-OH)4) 1 / 6 CO2(Hf(μ3-O)4(μ3-OH)4) 1 / 6 ,Ph-CO2(Zr(μ3-O)4(μ3-OH)4) 1 / 6 ,Ph-CO2(Hf(μ3-O)4(μ3-OH)4) 1 / 6 One or more of them, where Ph is a benzene ring.

[0010] Specifically, it has the following structural formulas (Ⅰ-1) to (Ⅰ-6):

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

[0017] This invention also discloses a method for preparing the aforementioned two-dimensional metal-organic layer based on polynitrogen ligands, comprising:

[0018] (1) Prepare polynitrogen ligands as shown in formulas (Ⅱ-1) to (Ⅱ-3);

[0019]

[0020]

[0021] (2) The polynitrogen ligand, the soluble salt of the coordination metal, the structure modifier and the solvent are mixed to obtain a mixture, and the mixture is prepared by solvothermal reaction to obtain the two-dimensional metal-organic layer based on the polynitrogen ligand.

[0022] In step (1), the preparation process of the polynitrogen ligand as described in formula (Ⅱ-1) is as follows:

[0023] Using 2-acrylonitrile-5-methylpyridine as a raw material, an intermediate product was obtained by heating and melting condensation, and then oxidized with potassium permanganate to obtain the polynitrogen ligand as described in formula (Ⅱ-1).

[0024] The heating and melting condensation temperature is 100-140°C, preferably 120°C.

[0025] The potassium permanganate oxidation process uses pyridine as a solvent, and potassium permanganate is added in the form of an aqueous solution of potassium permanganate; the oxidation reaction temperature is the reflux temperature.

[0026] In step (1), the preparation process of the polynitrogen ligand as described in formula (Ⅱ-2) is as follows:

[0027] Using 2-acrylonitrile-5-bromopyridine as a raw material, intermediate product I was obtained by heating and melting condensation. Then, intermediate product II was prepared by coupling reaction with 4-methylcarbonylphenylboronic acid under the catalysis of tetrakis(triphenylphosphine)palladium. Finally, hydrolysis reaction was carried out under alkaline conditions to obtain the polynitrogen ligand as described in formula (II-2).

[0028] The heating and melting condensation temperature is 120-180°C, preferably 150°C.

[0029] The coupling reaction is carried out in a THF / water mixed solvent at a temperature of 60–80 °C.

[0030] The hydrolysis reaction is carried out in KOH aqueous solution at a temperature of 60–80 °C.

[0031] In step (1), the preparation process of the polynitrogen ligand as described in formula (Ⅱ-3) is as follows:

[0032] Using 2-nitrile-5-bromo-pyrimidine as a raw material, intermediate 1 was obtained by condensation reaction, and then intermediate 2 was prepared by coupling reaction with 4-methylcarbonylphenylboronic acid under tetrakis(triphenylphosphine)palladium catalysis. Finally, hydrolysis reaction was carried out under alkaline conditions to obtain the polynitrogen ligand as shown in formula (II-3).

[0033] The condensation reaction is carried out in n-pentanol at a temperature of 120–150°C, preferably 135°C.

[0034] The coupling reaction is carried out in a THF / water mixed solvent at a temperature of 60–80 °C.

[0035] The hydrolysis reaction is carried out in the presence of cesium carbonate at a temperature of 60–80 °C.

[0036] In step (2):

[0037] The soluble salt of the coordination metal is selected from soluble zirconium salts and / or soluble hafnium salts;

[0038] The structure modifier is selected from one or more of benzoic acid, formic acid, and trifluoroacetic acid;

[0039] The solvent is selected from one or more of N,N-dimethylformamide and N,N-dimethylacetamide.

[0040] Preferably, in step (2):

[0041] With the amount of the polynitrogen ligand added being 1 equivalent, the amount of the soluble salt of the coordination metal added is 3.5 to 28 equivalents, and the amount of the structure modifier added is 50 to 200 equivalents;

[0042] In the mixture, the concentration of the polynitrogen ligand is 2.5–7.5 mmol / L;

[0043] The solvothermal reaction is carried out at a temperature of 80–120°C for a duration of 16–48 h.

[0044] The present invention also discloses the application of the two-dimensional metal-organic layer based on multi-nitrogen ligands in the field of biomacromolecule loading, wherein the biomacromolecule is selected from nucleic acid drugs and / or proteins.

[0045] Tests have shown that the two-dimensional metal-organic layer prepared by this invention can be used to load biomolecules with a high loading capacity and no limitation on the size of the molecules. More importantly, the loading of the two-dimensional metal-organic layer does not significantly reduce the original biological activity of the biomolecules.

[0046] Preferably, the two-dimensional metal-organic layer is selected from two-dimensional metal-organic layers with the structure of formula (I-3), which not only has a high loading capacity for biological macromolecules, but also does not affect their original biological activity.

[0047] The present invention also discloses the application of the two-dimensional metal-organic layer-supported olefin reductase based on multi-nitrogen ligands in the photocatalytic asymmetric hydrogenation reaction of olefins.

[0048] Tests have shown that the two-dimensional metal-organic layer prepared by this invention can catalyze the cis-trans isomerization of olefins under light irradiation, and can achieve asymmetric hydrogenation of olefins after loading olefin reductase on it, with very high chiral selectivity.

[0049] Compared with the prior art, the present invention has the following advantages:

[0050] This invention prepares a series of novel two-dimensional metal-organic layers based on various novel polynitrogen ligands. The novel structure can achieve efficient loading of biomacromolecules while basically not affecting their original biological activity. In addition, the novel polynitrogen ligands endow the two-dimensional metal-organic layers with more unique optical properties, enabling them to achieve photocatalytic olefin isomerization of olefins and to achieve asymmetric hydrogenation of olefins in series with the loaded olefin reductase. Attached Figure Description

[0051] Figure 1 The 1H NMR spectrum of TPYP-Me3, the intermediate product of the polynitrogen ligand synthesis prepared in Example 1;

[0052] Figure 2The 1H NMR spectrum of the polynitrogen ligand TPYP-H3 prepared in Example 1;

[0053] Figure 3 A scanning electron microscope image of the two-dimensional metal-organic layer prepared in Example 1;

[0054] Figure 4 Transmission electron microscopy image of the two-dimensional metal-organic layer prepared in Example 1;

[0055] Figure 5 Powder X-ray diffraction pattern and fitted pattern of the two-dimensional metal-organic layer prepared in Example 1;

[0056] Figure 6 The 1H NMR spectrum of TPYT-Br3, the intermediate product of the polynitrogen ligand synthesis prepared in Example 2;

[0057] Figure 7 The 1H NMR spectrum of TPYT-BM3, the intermediate product of the polynitrogen ligand synthesis prepared in Example 2;

[0058] Figure 8 The 1H NMR spectrum of the polynitrogen ligand TPYT-BH3 prepared in Example 2;

[0059] Figure 9 Scanning electron microscope image of the two-dimensional metal-organic layer prepared in Example 2;

[0060] Figure 10 Transmission electron microscopy image of the two-dimensional metal-organic layer prepared in Example 2;

[0061] Figure 11 The powder X-ray diffraction pattern and fitted pattern of the two-dimensional metal-organic layer prepared in Example 2 are shown below.

[0062] Figure 12 The 1H NMR spectrum of TPMT-Br3, the intermediate product of the polynitrogen ligand synthesis prepared in Example 3;

[0063] Figure 13 The 1H NMR spectrum of TPMT-BM3, the intermediate product of the polynitrogen ligand synthesis prepared in Example 3;

[0064] Figure 14 The 1H NMR spectrum of the polynitrogen ligand TPMT-BH3 prepared in Example 3;

[0065] Figure 15 A scanning electron microscope image of the two-dimensional metal-organic layer prepared in Example 3;

[0066] Figure 16 Transmission electron microscopy image of the two-dimensional metal-organic layer prepared in Example 3;

[0067] Figure 17The powder X-ray diffraction pattern and fitted pattern of the two-dimensional metal-organic layer prepared in Example 3 are shown.

[0068] Figure 18 Scanning electron microscope image of the two-dimensional metal-organic layer prepared for comparison;

[0069] Figure 19 Transmission electron microscope (TEM) image of a two-dimensional metal-organic layer prepared for comparison.

[0070] Figure 20 The diagram shows the activity of free β-galactosidase and immobilized β-galactosidase.

[0071] Figure 21 A schematic diagram of the photocatalytic asymmetric hydrogenation reaction of Z-configured olefins (a) and a comparison of olefin isomerization and reduction with and without a metal-organic layer (b). Detailed Implementation

[0072] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0073] Example 1

[0074] (1) Synthesis of polynitrogen ligand TPYP-H3

[0075]

[0076] 5 g of 2-acrylonitrile-5-methylpyridine was placed in a pressure-resistant tube and heated to 120 °C until melted. Then, 169 mg (0.1 equivalent) of sodium hydroxide was added to the tube. After reacting at 120 °C for 36 hours, a black solid was obtained. Purification was performed by column chromatography using dichloromethane and methanol as eluents. Finally, 1.8 g of TPYP-Me3 was obtained, with a yield of approximately 36%.

[0077] Figure 1 The 1H NMR spectrum of the polynitrogen ligand synthesis intermediate (TPYP-Me3) prepared in this embodiment.

[0078]

[0079] 0.40 g of TPYP-Me3 was dissolved in 25 mL of pyridine, and then 90 mL of KMnO4 aqueous solution (containing 8 g of KMnO4) was added. After reflux at 100 °C for 96 hours, 40 mL of 1 mol / L hydrochloric acid was added to precipitate the product. The precipitate was obtained by centrifugation and washed with methanol to give 0.62 g of TPYP-H3, with a yield of approximately 98%.

[0080] Figure 2 The 1H NMR spectrum of the polynitrogen ligand (TPYP-H3) prepared in this embodiment.

[0081] (2) Synthesis of two-dimensional metal-organic layers

[0082] Weigh 40 mg (1 equivalent) of the polynitrogen ligand TPYP-H3 prepared in step (1) and dissolve it in 4 mL of N,N-dimethylformamide. Add 610 μL (92 equivalents) of trifluoroacetic acid to the above solution. Weigh 800 mg (28 equivalents) of zirconium oxychloride octahydrate and dissolve it in 4 mL of N,N-dimethylformamide. Add the solution to the aforementioned ligand solution and finally add an additional 4 mL of N,N-dimethylformamide. The reaction conditions are: stand in an oven at 120 °C for 24 h.

[0083] Figure 3 , 4 The images shown are scanning electron microscope (SEM) and transmission electron microscope (TEM) images of the two-dimensional metal-organic layer prepared in this embodiment. Observation reveals that the two-dimensional metal-organic layer prepared in this embodiment has a film-like structure.

[0084] Figure 5 The powder X-ray diffraction pattern and simulated signal of the two-dimensional metal-organic layer prepared in this embodiment show that its structural formula is as shown in formula (Ⅰ-1).

[0085] Example 2

[0086] (1) Synthesis of polynitrogen ligand TPYT-BH3

[0087]

[0088] 5 g of 2-acrylonitrile-5-bromopyridine was placed in a pressure-resistant tube and heated to 150 °C until melted. Then, 218 mg (0.2 equivalents) of sodium hydroxide was added to the tube. After reacting at 150 °C for 24 hours, a black solid was obtained. This solid was dissolved in N-methylpyrrolidone and then purified by recrystallization with methanol. Finally, 2.3 g of TPYT-Br3 was obtained, with a yield of approximately 46%.

[0089] Figure 6 The 1H NMR spectrum of the polynitrogen ligand synthesis intermediate (TPYT-Br3) prepared in this embodiment.

[0090]

[0091] 1.16 mg TPYT-Br3, 1.71 g 4-methylcarbonylphenylboronic acid (4.5 equivalents), and 5.78 g cesium fluoride (18 equivalents) were added to a THF and water mixture (140 mL THF and 40 mL H2O) after Ar bubbling for 30 min. Ar bubbling was continued in the suspension for another 30 min, followed by the addition of 367 mg tetrakis(triphenylphosphine)palladium (0.15 equivalents). After heating at 70 °C for 72 hours, the precipitate was filtered and washed with methanol to obtain 1.44 g TPYT-BM3, with a yield of approximately 95%.

[0092] Figure 7 The 1H NMR spectrum of the polynitrogen ligand synthesis intermediate (TPYT-BM3) prepared in this embodiment.

[0093]

[0094] 0.67 g of TPYT-BM3 was suspended in 25 mL of methanol, and then 25 mL of 1 mol / L KOH aqueous solution was added. After heating at 70 °C for 24 hours, 50 mL of water was added to fully dissolve the product, and the mixture was filtered. The filtrate was collected, and after acidification, a precipitate formed. The precipitate was filtered again, washed with methanol, and dried in a vacuum drying oven to obtain 0.62 g of TPYT-BH3, with a yield of approximately 98%.

[0095] Figure 8 The 1H NMR spectrum of the polynitrogen ligand (TPYT-BH3) prepared in this embodiment.

[0096] (2) Synthesis of two-dimensional metal-organic layers

[0097] Weigh 60 mg (1 equivalent) of the polynitrogen ligand TPYT-BH3 prepared in step (1) and dissolve it in 4 mL of N,N-dimethylformamide. Add 610 μL (92 equivalents) of trifluoroacetic acid to the above solution. Weigh 800 mg (28 equivalents) of zirconium oxychloride octahydrate and dissolve it in 1 mL of N,N-dimethylformamide. Add the solution to the aforementioned ligand solution and finally add an additional 4 mL of N,N-dimethylformamide. The reaction conditions are: stand in an oven at 120 °C for 24 hours.

[0098] Figure 9 , 10 The images shown are scanning electron microscope (SEM) and transmission electron microscope (TEM) images of the two-dimensional metal-organic layer prepared in this embodiment. Observation reveals that the two-dimensional metal-organic layer prepared in this embodiment has a film-like structure.

[0099] Figure 11 The powder X-ray diffraction pattern and simulated signal of the two-dimensional metal-organic layer prepared in this embodiment show that its structural formula is as shown in formula (Ⅰ-2).

[0100] Example 3

[0101] (1) Synthesis of polynitrogen ligand TPMT-BH3

[0102]

[0103] 10 mL of n-pentanol was added to a mixture of 5 g of 2-acrylonitrile-5-bromopyrimidine, 237 μL of N,N-diisopropylethylamine (0.05 equivalent), and 133 mg of ammonium bromide (0.05 equivalent). After heating at 135 °C for 24 hours, methanol was added to the suspension to precipitate the product. Recrystallization from the product with NMP and methanol yielded approximately 2.5 g of TPMT-Br3, with a yield of approximately 50%.

[0104] Figure 12 The 1H NMR spectrum of the polynitrogen ligand synthesis intermediate (TPMT-Br3) prepared in this embodiment.

[0105]

[0106] 1.5 g of TPMT-Br3, 2.2 g of (4-(methoxycarbonyl)phenyl)boronic acid (4.5 equivalents), and 7.43 g of cesium fluoride (18 equivalents) were added to a THF and water mixture (250 mL THF and 80 mL H2O) after Ar bubbling for 30 min. Ar bubbling was continued in the suspension for another 30 min, followed by the addition of 471 mg of tetrakis(triphenylphosphine)palladium (0.15 equivalents). After heating at 70 °C for 72 hours, the precipitate was filtered and washed with methanol to obtain 1.95 g of TPMT-BM3, with a yield of approximately 95%.

[0107] Figure 13 The 1H NMR spectrum of the polynitrogen ligand synthesis intermediate (TPMT-BM3) prepared in this embodiment.

[0108]

[0109] 1.5 g of TPMT-BM3 was suspended in 120 mL of N-methylpyrrolidone, and then 5.4 g of cesium carbonate (8 equivalents) and 80 mL of water were added. After heating at 70 °C for 24 hours, 160 mL of water was added to fully dissolve the product, and the mixture was filtered. The filtrate was collected, and after acidification, a precipitate formed. The precipitate was filtered again, washed with methanol, and dried in a vacuum drying oven to obtain 1.2 g of TPMT-BH3, with a yield of approximately 80%.

[0110] Figure 14 The 1H NMR spectrum of the polynitrogen ligand (TPMT-BH3) prepared in this embodiment.

[0111] (2) Synthesis of two-dimensional metal-organic layers

[0112] Weigh 60 mg (1 equivalent) of the polynitrogen ligand TPMT-BH3 prepared in step (1) and dissolve it in 4 mL of N,N-dimethylformamide. Add 610 μL (92 equivalents) of trifluoroacetic acid to the above solution. Weigh 800 mg (28 equivalents) of zirconium oxychloride octahydrate and dissolve it in 1 mL of N,N-dimethylformamide. Add the solution to the aforementioned ligand solution and finally add an additional 4 mL of N,N-dimethylformamide. The reaction conditions are: oven drying at 120 °C for 24 hours.

[0113] Figure 15 , 16 The images shown are scanning electron microscope (SEM) and transmission electron microscope (TEM) images of the two-dimensional metal-organic layer prepared in this embodiment. Observation reveals that the two-dimensional metal-organic layer prepared in this embodiment has a film-like structure.

[0114] Figure 17 The powder X-ray diffraction pattern and simulated signal of the two-dimensional metal-organic layer prepared in this embodiment show that its structural formula is as shown in formula (Ⅰ-3).

[0115] Comparative Example

[0116] Weigh 40 mg (1 equivalent) of the organic ligand BTB (commercially available) and dissolve it in 4 mL of N,N-dimethylformamide. Add 610 μL (92 equivalents) of trifluoroacetic acid to the above solution. Weigh 800 mg (28 equivalents) of zirconium oxychloride octahydrate and dissolve it in 1 mL of N,N-dimethylformamide. Add this solution to the aforementioned ligand solution, and finally add an additional 4 mL of N,N-dimethylformamide. The reaction conditions are: oven drying at 120 °C for 24 hours.

[0117]

[0118] Figure 18 , 19 The images shown are scanning electron microscope (SEM) and transmission electron microscope (TEM) images of the two-dimensional metal-organic layer prepared in this comparative example. Observation reveals that the two-dimensional metal-organic layer prepared in this comparative example also possesses a film-like structure.

[0119] Performance testing:

[0120] I. Large-size protein loading

[0121] 10 μL of β-galactosidase solution (20 mg / mL) was mixed with 100 μL of two-dimensional metal-organic layer aqueous suspensions (1 mg / mL) prepared in Examples 1, 2, 3, and the comparative example, respectively, and the mixture was shaken in a shaker at 10 °C for 20 minutes. The two-dimensional metal-organic layers were then separated by centrifugation. 25 μL of the supernatant was mixed with 5 μL of 6x protein electrophoresis loading buffer and boiled at 100 °C for 10 minutes. After the mixture cooled to room temperature, polyacrylamide gel electrophoresis was performed. The gels were then stained with Coomassie Brilliant Blue. Proteins on the gel were stained blue, while gels without proteins were not stained. The images were destaining, and the amount of protein adsorbed was determined based on the grayscale values. The calculations obtained using the above method showed that the loading capacity of the two-dimensional metal-organic layer I-1 prepared in Example 1, the two-dimensional metal-organic layer I-2 prepared in Example 2, the two-dimensional metal-organic layer I-3 prepared in Example 3, and the two-dimensional metal-organic layer prepared in the comparative example for β-galactosidase reached 1 g / g, 210 mg / g, 740 mg / g, and 1 g / g, respectively.

[0122] Subsequently, the activities of free β-galactosidase and immobilized β-galactosidase were determined based on GB / T 33409-2016. (See below) Figure 20 As shown, the β-galactosidase immobilized by the two-dimensional metal-organic layers I-2 and I-3 basically retained its original activity, while the activity of the β-galactosidase immobilized by the two-dimensional metal-organic layer I-1 decreased; and the activity of the β-galactosidase immobilized by the two-dimensional metal-organic layer prepared in the comparative example decreased significantly again, with an activity of less than 50%.

[0123] The above tests revealed that the two-dimensional metal-organic layers prepared using this invention can be used to load biomolecules, exhibiting high loading capacity and without limitations on molecule size. Examples demonstrate the effects of three metal-organic layers on galactosidase. The loading is sufficient, and the catalytic activity of the enzyme is basically unaffected after loading.

[0124] II. Photocatalytic olefin isomerization and enzyme-supported asymmetric hydrogenation reactions

[0125] 50 μL of sucralose enzyme II (OYE2, 49.2 nmol / L) was mixed with 100 μL of the two-dimensional metal-organic layer (I-3) (1 mmol / L) prepared in Example 3. Then, 100 nmol of nicotinamide adenine dinucleotide phosphate, 12.5 μmol of glucose, 0.55 nmol of glucose dehydrogenase, 125 μL of HEPES buffer (pH = 7.5, 10 mmol / L), and 2.5 μmol of the Z-configuration olefin substrate ((Z)-3-cyano-3-phenylacrylate methyl ester) were added. After reacting at 15 °C under 460 nm blue light for 14 hours, the product distribution was determined by chiral gas chromatography. In the metal-organic layer-free experiment as a control group, only 100 μL of (I-3) was replaced with 100 μL of pure water, keeping the total volume constant; all other steps were exactly the same as the experimental group.

[0126] Figure 21 Figure 'a' is a schematic diagram of the photocatalytic asymmetric hydrogenation reaction of Z-configured olefins. This reaction proceeds in two steps: the first step is an isomerization reaction that converts the Z configuration to the E configuration, and the second step is a hydrogenation reduction reaction. Figure 21 Figure b compares the isomerization and reduction of olefins with and without a metal-organic layer. The comparison reveals that OYE2 selectively catalyzes the hydrogenation of E-configuration olefin substrates but not Z-configuration substrates; therefore, the reaction cannot proceed in the sample without a metal-organic layer. In contrast, the two-dimensional metal-organic layer (Ⅰ-3) prepared in this invention can catalyze cis-trans isomerization of olefins under light irradiation and can achieve asymmetric hydrogenation of olefins after loading an olefin reductase, exhibiting very high chiral selectivity.

[0127] The above-described embodiments are preferred embodiments, but the scope of protection of the present invention is not limited thereto. Those skilled in the art can easily understand the spirit of the present invention based on the above embodiments and make different extensions and variations, but as long as they do not depart from the spirit of the present invention, they are all within the scope of protection of the present invention.

Claims

1. A two-dimensional metal-organic layer based on polyazido ligands, characterized in that, It has the following structural formulas (Ⅰ-1) to (Ⅰ-3): （Ⅰ-1）； （Ⅰ-2）； （Ⅰ-3）。 2. A method for the preparation of a two-dimensional metal-organic layer based on polyazido ligands according to claim 1, characterized in that, include: (1) Prepare polynitrogen ligands as shown in formulas (II-1) to (II-3); （Ⅱ-1）； （Ⅱ-2）； （Ⅱ-3）； (2) The polynitrogen ligand, the soluble salt of the coordination metal, the structure modifier and the solvent are mixed to obtain a mixture, and the mixture is prepared by solvothermal reaction to obtain the two-dimensional metal-organic layer based on the polynitrogen ligand.

3. The method for preparing a two-dimensional metal-organic layer based on polyazido ligands according to claim 2, characterized in that, In step (1), the preparation process of the polynitrogen ligand as described in formula (Ⅱ-1) is as follows: Using 2-acrylonitrile-5-methylpyridine as a raw material, an intermediate product was obtained by heating and melting condensation, and then oxidized with potassium permanganate to obtain the polynitrogen ligand as described in formula (Ⅱ-1).

4. The method for preparing a two-dimensional metal-organic layer based on multi-nitrogen ligands according to claim 2, characterized in that, In step (1), the preparation process of the polynitrogen ligand as described in formula (Ⅱ-2) is as follows: Using 2-acrylonitrile-5-bromopyridine as a raw material, intermediate product I was obtained by heating and melting condensation. Then, intermediate product II was prepared by coupling reaction with 4-methylcarbonylphenylboronic acid under the catalysis of tetrakis(triphenylphosphine)palladium. Finally, hydrolysis reaction was carried out under alkaline conditions to obtain the polynitrogen ligand as described in formula (II-2).

5. The method for preparing a two-dimensional metal-organic layer based on multi-nitrogen ligands according to claim 2, characterized in that, In step (1), the preparation process of the polynitrogen ligand as described in formula (Ⅱ-3) is as follows: Using 2-nitrile-5-bromo-pyrimidine as a raw material, intermediate 1 was obtained by condensation reaction, and then intermediate 2 was prepared by coupling reaction with 4-methylcarbonylphenylboronic acid under tetrakis(triphenylphosphine)palladium catalysis. Finally, hydrolysis reaction was carried out under alkaline conditions to obtain the polynitrogen ligand as described in formula (II-3).

6. The method for preparing a two-dimensional metal-organic layer based on multi-nitrogen ligands according to claim 2, characterized in that, In step (2): The soluble salt of the coordination metal is selected from soluble zirconium salts; The structure modifier is selected from one or more of benzoic acid, formic acid, and trifluoroacetic acid; The solvent is selected from one or more of N,N-dimethylformamide and N,N-dimethylacetamide.

7. The method for preparing a two-dimensional metal-organic layer based on multi-nitrogen ligands according to claim 2, characterized in that, In step (2): With the amount of the polynitrogen ligand added being 1 equivalent, the amount of the soluble salt of the coordination metal added is 3.5 to 28 equivalents, and the amount of the structure modifier added is 50 to 200 equivalents; In the mixture, the concentration of the polynitrogen ligand is 2.5–7.5 mmol / L; The solvothermal reaction is carried out at a temperature of 80~120℃ for a time of 16~48 h.

8. An application of the two-dimensional metal-organic layer based on multi-nitrogen ligands according to claim 1 in the field of biomacromolecule loading, characterized in that, The biomolecules are selected from nucleic acid drugs and / or proteins.

9. The application of a two-dimensional metal-organic layer-supported olefin reductase based on multi-nitrogen ligands as described in claim 1 in photocatalytic olefin isomerization and asymmetric hydrogenation reactions.

Images