Multi-nested framework material MNF-2 constructed based on dynamic B-N keys and preparation method of multi-nested framework material MNF-2

Abstract

The invention discloses a multiple nested framework material MNF-2 constructed based on a dynamic B <-N bond and a preparation method of the multiple nested framework material MNF-2. The material MNF-2 is prepared from monomer molecules, 1, 4-phenylenediboronic acid and 4-chlorocatechol as raw materials; wherein 1, 4-benzene diboronic acid and 4-chlorocatechol are dehydrated to generate a boric acid ester structure, and B atoms of boric acid ester are combined with N atoms in monomer molecules to form B <-N coordinate bonds. A monomer molecule 4, 4, 8, 8, 12, 12-hexamethyl-2, 6, 10-tri (4-pyridyl)-8, 12-dihydro-4H-benzo [9, 1] quinolizino [3, 4, 5, 6, 7-defg] anthracene (monomer molecule M1 for short) is synthesized firstly, the monomer molecule M1 and a lewis acid molecule (4-chlorocatechol) are subjected to a one-pot method through a B <-N bond in a solution to effectively generate an MNF material, and a two-dimensional lamellar structure is formed. The lamellar material has excellent mechanical properties. The acting force range of the two-dimensional MNF material is further widened, and a new strategy is provided for preparation of the two-dimensional MNF material.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of organic framework materials, and relates to a coordination B←N multiple nested framework material, in particular to a multiple nested framework material MNF-2 based on dynamic B←N bond construction and a preparation method thereof. BACKGROUND

[0002] In the past three decades, the rise of metal-organic frameworks (MOFs) has led to a revolution in molecular topology and solid-state chemistry. The core lies in the rational design of material structure and function through network chemistry, which not only promotes the application of MOFs in gas storage, separation and catalysis, but also gives birth to the covalent organic framework (COF). In this process, the scientific community began to explore the use of weaker interactions (such as hydrogen bonds) to construct topological frameworks, thus developing hydrogen-bonded organic frameworks (HOFs) with excellent reversibility and recyclability.

[0003] Under this background, coordination B←N-based frameworks emerge as a new type of framework material. The B←N bond binding energy (about 100 kJ / mol) between the building units is significantly higher than that of traditional hydrogen bonds, indicating its great potential in structural stability and crystallinity. However, currently, coordination B←N-based framework materials still exist mostly in amorphous state and lack stability, which seriously restricts their development. Therefore, developing two-dimensional framework materials with high stability and clear topological structure has become a key challenge and research goal in this field. SUMMARY

[0004] In view of the deficiencies in the prior art, the purpose of the present application is to provide a multiple nested framework material MNF-2 based on dynamic B←N bond construction and a preparation method thereof, which solves the technical problem that coordination B←N-based framework materials in the prior art still exist mostly in amorphous state and lack stability, resulting in limited application.

[0005] In order to solve the above technical problems, the present application adopts the following technical solutions: A multiple nested framework material MNF-2 based on dynamic B←N bond construction, which is prepared from monomer molecules, 1,4-benzenediol and 4-chlororesorcinol as raw materials; wherein the 1,4-benzenediol and 4-chlororesorcinol are dehydrated to generate a borate ester structure, and the B atom of the borate ester is combined with the N atom in the monomer molecule to form a B←N coordination bond.

[0006] The chemical structure of the monomer molecule is shown in the following formula V: Formula V.

[0007] In the formula: R1 is selected from any one of methyl, hydrogen, C2-C20 alkyl, and methoxy.

[0008] Preferably, R1 is methyl, and the chemical structure of the monomer molecule is shown in the following formula V-1: Formula V-1.

[0009] Specifically, the multiple nested framework material MNF-2 constructed based on dynamic B←N bonds belongs to a trigonal system and a space group P3c1.

[0010] The application also protects a preparation method of the multiple nested framework material MNF-2 constructed based on dynamic B←N bonds, which comprises the following steps: first, synthesizing an intermediate product by taking 4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolizino[3,4,5,6,7-defg]anthrazoline and N-bromosuccinimide as reaction raw materials; then, synthesizing a monomer molecule by taking the intermediate product and 4-pyridine boronic acid as reaction raw materials; and finally, synthesizing the multiple nested framework material MNF-2 constructed based on dynamic B←N bonds by taking the monomer molecule, 1,4-benzenediboronic acid and 4-chloro-o-dihydroxybenzene as reaction raw materials. The synthesis route is as follows: .

[0011] The application also has the following technical features: Specifically, the method comprises the following steps: Step one, preparing a monomer molecule: Step 1.1: 4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolizino[3,4,5,6,7-defg]anthrazoline and N-bromosuccinimide are sequentially put into a reaction container, a solvent is added in a protective atmosphere, and stirring reaction is performed.

[0012] Step 1.2: after the reaction is completed, extraction is performed after the solvent is removed, then the organic layer is dried, the solvent is removed again to obtain a crude product; after the crude product is separated by column, 2,6,10-tribromo-4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolizino[3,4,5,6,7-defg]anthrazoline is obtained.

[0013] Step 1.3: 2,6,10-tribromo-4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolizino[3,4,5,6,7-defg]anthrazoline, 4-pyridine boronic acid, a catalyst and a base obtained in step 1.2 are added into a reaction container, a solvent is added in a protective atmosphere, and stirring reaction is performed under condensation reflux.

[0014] Step 1.4: After the reaction is completed, the solvent is removed, and then extraction is performed, and then the organic layer is dried, and the solvent is removed again to obtain a crude product; the crude product is separated by column to obtain a monomer molecule.

[0015] Step two, the monomer molecule prepared in step one, 1,4-benzenediboronic acid, 4-chloro o-benzene diol are placed in a reaction vessel, then a solvent is added, and the reaction is heated; after the reaction is completed, it is cooled to crystallization, and a multi-nested framework material MNF-2 based on dynamic B←N bond construction is obtained.

[0016] Specifically, in step 1.1, the stirring reaction conditions are: stirring uniformly at 15-35°C for 12-36 hours.

[0017] Specifically, in step 1.1, the mass ratio of 4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolizino[3,4,5,6,7-defg]anthracene and N-bromosuccinimide is 1:(1.5-2.5). Preferably, the ratio is 1:1.95.

[0018] Specifically, in step 1.1, the solvent is selected from one or more of chloroform, dichloromethane, toluene, methanol, and acetonitrile.

[0019] Specifically, in steps 1.2 and 1.4, the extraction conditions are: adding saturated brine, and then extracting twice or three times with dichloromethane.

[0020] Specifically, in steps 1.2 and 1.4, the eluent used for column separation is a mixed solvent of petroleum ether and dichloromethane, and the volume ratio of the two is 10:1.

[0021] Specifically, in step 1.3, the catalyst is selected from tetrakis triphenylphosphine palladium, PdCl2(dppf), and Buchwald catalyst, Pd(dtBPF)Cl2. Preferably, it is tetrakis triphenylphosphine palladium.

[0022] Specifically, in step 1.3, the base is selected from anhydrous potassium carbonate, sodium carbonate, cesium carbonate, and potassium phosphate. Preferably, it is anhydrous potassium carbonate.

[0023] Specifically and preferably, in step 1.3, the mass ratio of 2,6,10-tribromo-4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolizino[3,4,5,6,7-defg]anthracene, 4-pyridine boronic acid, tetrakis triphenylphosphine palladium, and anhydrous potassium carbonate is (500-700):(400-600):(25-75):(450-650). Preferably, the ratio is 614:492:50:550.

[0024] Specifically, in step 1.3, the stirring reaction under condensation reflux is at 60-100℃ under constant temperature stirring for 36-72h. Preferably, at 80℃ under constant temperature stirring for 48h.

[0025] Specifically and preferably, in step 1.3, the solvent is a mixture of tetrahydrofuran and water, with a volume ratio of 2:1.

[0026] Specifically, in step two, the mass ratio of monomer molecules, 1,4-benzenediboronic acid, and 4-chloro-o-benzosemicarbazide is (1-3):(2-5):(3-8). Preferably, it is 2:3:6.

[0027] Specifically, in step two, the heating reaction is at 120-160℃ for 1-3h. Preferably, it is at 135℃ for 1h.

[0028] Specifically, in step two, the solvent is o-dichlorobenzene.

[0029] Specifically, in step two, the cooling time is 48-96h.

[0030] Compared with the prior art, the present application has the following technical effects: The present application first synthesizes monomer molecules 4,4,8,8,12,12-hexamethyl-2,6,10-tris(4-pyridyl)-8,12-dihydro-4H-benzo[9,1]quinolizino[3,4,5,6,7-defg]anthracene (referred to as monomer molecule M1). The monomer molecule M1 effectively generates the MNF material through one-pot method by B←N bond with Lewis acid molecules (4-chloro-o-benzosemicarbazide) in solution, forming a two-dimensional sheet structure. This sheet material has excellent mechanical properties. The present application further broadens the force range of two-dimensional MNF materials and provides a new strategy for the preparation of two-dimensional MNF materials. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 is the nuclear magnetic resonance hydrogen spectrum of monomer molecule M1.

[0032] Figure 2 is the nuclear magnetic resonance carbon spectrum of monomer molecule M1.

[0033] Figure 3 is the mass spectrum of monomer molecule M1.

[0034] Figure 4 is the infrared spectrum of monomer molecule M1.

[0035] Figure 5 is the PXRD graph of the multiple nested framework material MNF-2 based on dynamic B←N bond construction.

[0036] Figure 6 is a force curve plot of a two-dimensional MNF material of a multi-nested framework material MNF-2 constructed based on dynamic B←N bonds.

[0037] Figure 7 is a TEM electron microscope image of a two-dimensional MNF material of a multi-nested framework material MNF-2 constructed based on dynamic B←N bonds.

[0038] Figure 8 is a ball-and-stick model of single crystal XRD of a multi-nested framework material MNF-2 constructed based on dynamic B←N bonds.

[0039] Figure 9 is a comparative infrared spectrum of a monomeric molecule M1 and a multi-nested framework material MNF-2 constructed based on dynamic B←N bonds.

[0040] The specific content of the present application is further explained in detail in combination with the following examples. DETAILED DESCRIPTION

[0041] It should be noted that all raw materials in the present application, in the absence of special instructions, adopt the raw materials known in the art. For example: 4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolizino[3,4,5,6,7-defg]anthrazoline is a compound known in the prior art, and its CAS code is 52066-63-4.

[0042] In accordance with the above technical solution, the specific embodiments of the present application are given below. It should be noted that the present application is not limited to the following specific embodiments, and any equivalent transformation made on the basis of the technical solution of the present application falls within the protection scope of the present application.

[0043] Example 1 This embodiment gives a preparation method of a monomeric molecule M1 (a compound shown in formula V-1), and the synthetic route is as follows: .

[0044] The method specifically comprises the following steps: Step 1.1: 1.00 g of 4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolizino[3,4,5,6,7-defg]anthrazoline (a compound shown in formula I-1), 1.95 g of N-bromosuccinimide (a compound shown in formula II) are sequentially put into a 150 mL Schlenk bottle, 30 mL of chloroform is added under a nitrogen environment, and stirring is uniformly carried out at room temperature for 24 hours.

[0045] Step 1.2: After the reaction is completed, the solvent is removed by a rotary evaporator, saturated brine is added, and then extracted with dichloromethane two to three times. The organic layer is taken and dried over anhydrous sodium sulfate, and the solvent is removed by a rotary evaporator to obtain a crude product. The crude product is separated by column using petroleum ether: dichloromethane = 10: 1 (v / v) to obtain 1.62 g of 2,6,10-tribromo-4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H- benzo[9,l]quinolizino[3,4,5,6,7-defg]anthracene (the compound shown in Formula III-1), which has the following characterization data: v : v ) to obtain 1.62 g of 2,6,10-tribromo-4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H- benzo[9,l]quinolizino[3,4,5,6,7-defg]anthracene (the compound shown in Formula III-1), which has the following characterization data: 1 H NMR (300MHz, CDCl3) δ 7.44 (s, 6H), 1.58 (s, 18H). 13 C-NMR (75MHz, CDCl3) δ 131.7, 126.5, 116.3, 35.8, 32.7. Mass-EI: 585.9 (M + ,100), 587.8 (M + , 97), 600.8 (M + , 26), 602.8 (M + , 24). Anal. Calcd forC 27 H 24 Br3N: C, 53.85; H, 4.02; N, 2.33. Found: C, 53.59; H, 3.91; N, 2.41. The compound is a white foamy solid, and the yield in this example is 98%.

[0046] Step 1.3: 614 mg of 2,6,10-tribromo-4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H- benzo[9,l]quinolizino[3,4,5,6,7-defg]anthracene (the compound shown in Formula III-1), 492 mg of 4-pyridineboronic acid (the compound shown in Formula IV), 50 mg of tetraphenylphosphonium palladium, and 550 mg of anhydrous potassium carbonate are added into a 100 mL Schlenk flask, 20 mL of tetrahydrofuran and 10 mL of water are added under a nitrogen environment. Stir the reaction at a constant temperature under a condensation reflux at 80°C for 48 h.

[0047] Step 1.4: After the reaction is completed, the solvent is removed by a rotary evaporator, saturated brine is added, and then extracted with dichloromethane two to three times. The organic layer is taken and dried over anhydrous sodium sulfate, and the solvent is removed by a rotary evaporator to obtain a crude product. The crude product is separated by column using petroleum ether: dichloromethane = 1:1 (v / v) to obtain 1.62 g of 2,6,10-tribromo-4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H- benzo[9,l]quinolizino[3,4,5,6,7-defg]anthracene (the compound shown in Formula III-1), which has the following characterization data: v v ​) column separation to obtain 271 mg of red solid, which has a nuclear magnetic resonance hydrogen spectrum as shown in Figure 1 , a nuclear magnetic resonance carbon spectrum as shown in Figure 2 , a mass spectrum as shown in Figure 3 , and an infrared spectrum as shown in Figure 4 . From the above characterization data, it can be known that the red solid product is the target molecule M1 (a compound shown in formula V-1), and the final yield of the embodiment is 45%.

[0048] Example 2 The embodiment provides a preparation method of a multi-nested framework material MNF-2 based on a dynamic B←N bond, and the method specifically comprises the following steps. Step one, preparation of a monomer molecule: for a specific process, see example 1.

[0049] Step two, placing the monomer molecule M1, 1,4-benzenediboronic acid and 4-chloro-o-dihydroxybenzene in a 20 mL sample bottle, and the mass ratio of the three is 2:3:6; then adding 18 mL of o-dichlorobenzene and heating to 135℃ for 1 h; after the reaction is completed, slowly cooling to room temperature for 96 h to obtain the MNF-2, i.e., a multi-nested framework (MNF) material based on a dynamic B←N bond.

[0050] It can be known from Figure 5 that the characteristic diffraction 2θ angle is 6.86°, 8.86°, 13.68°, 14.85°, 20.61°, 21.39°, 22.85°, which indicates that the crystallinity of the MNF-2 is good. It can be known from Figure 6 that the elastic modulus of the MNF-2 is as high as 16.624 GPa, which indicates that the rigidity is good. It can be known from Figure 7 that the MNF-2 presents a two-dimensional sheet structure. It can be known from Figure 8 that the MNF-2 has a multi-nested crystal structure. It can be known from Figure 9 that the characteristic infrared peak is 975, 1034 cm -1 , which indicates the existence of a B←N coordination bond. The MNF-2 belongs to a trigonal system, a space group P3c1, and the unit cell parameters a=18.1276(17), b=18.1276(17), c=25.281(4) Å.

[0051] The material prepared in the embodiment has a two-dimensional multi-nested framework material, has a high elastic modulus and strong rigidity, and is expected to be applied to the fields of high-efficiency separation and filtration membranes, reinforcing bodies of high-performance composite materials, protective coating barrier membranes and the like.

Claims

1. A multi-nested framework material MNF-2 based on dynamic B←N bonds, characterized in that, The material is prepared from monomer molecules, 1,4-phenyldiboronic acid and 4-chlorocatechol; wherein, 1,4-phenyldiboronic acid and 4-chlorocatechol are dehydrated to form a borate ester structure, and the B atom of the borate ester combines with the N atom in the monomer molecule to form a B←N coordinate bond; The chemical structural formula of the monomer molecule is shown in Formula V below: Formula V; In the formula: R1 is selected from any one of methyl, hydrogen, C2-C20 alkane group, and methoxy group.

2. The MNF-2 material, a multi-nested framework material based on dynamic B←N bonds, as described in claim 1, is characterized in that... R1 is a methyl group.

3. The MNF-2 material, a multi-nested framework material based on dynamic B←N bonds, as described in claim 2, is characterized in that... This material belongs to the trigonal crystal system, space group P3c1.

4. A method for preparing MNF-2, a multi-nested framework material based on dynamic B←N bonds as described in claim 2 or 3, characterized in that, The method includes: First, using 4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolrizino[3,4,5,6,7-defg]anthrazoline and N-bromosuccinimide as reactants, an intermediate product was synthesized. Then, using the intermediate product and 4-pyridineboronic acid as reactants, monomer molecules are synthesized. Finally, using monomer molecules, 1,4-benzenediboric acid, and 4-chlorocatechol as reactants, a multi-nested framework material MNF-2 based on dynamic B←N bond construction was synthesized.

5. The preparation method of MNF-2, a multi-nested framework material based on dynamic B←N bonds, as described in claim 4, is characterized in that: The reaction conditions for synthesizing the intermediate product include: stirring at 15–35°C for 12–36 hours; The reaction conditions for synthesizing monomer molecules include: constant temperature stirring reaction at 60-100℃ under reflux for 36-72 h; The reaction conditions for synthesizing MNF-2, a multi-nested framework material based on dynamic B←N bonds, include: reacting at 120–160 °C for 1–3 h.

6. The preparation method of MNF-2, a multi-nested framework material based on dynamic B←N bonds, as described in claim 4, is characterized in that... Includes the following steps: Step 1, Preparation of monomer molecules: Step 1.1: 4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolrizino[3,4,5,6,7-defg]anthrazoline and N-bromosuccinimide were added sequentially into the reaction vessel, and solvent was added under a protective atmosphere and the reaction was stirred. Step 1.2: After the reaction is complete, the solvent is removed and the mixture is extracted. The organic layer is then dried and the solvent is removed again to obtain the crude product. The crude product is separated by column chromatography to obtain 2,6,10-tribromo-4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolrizine[3,4,5,6,7-defg]anthracene. Step 1.3: The 2,6,10-tribromo-4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolazine[3,4,5,6,7-defg]anthracene, 4-pyridineboronic acid, catalyst and base obtained in Step 1.2 are added to the reaction vessel, the solvent is added under a protective atmosphere, and the reaction is stirred under reflux. Step 1.4: After the reaction is complete, the solvent is removed and extraction is performed. The organic layer is then dried and the solvent is removed again to obtain the crude product. The crude product is then separated by column chromatography to obtain monomer molecules. Step 2: Place the monomer molecules obtained in Step 1, 1,4-benzenediboric acid, and 4-chlorocatechol into a reaction vessel, then add solvent and heat to react; after the reaction is completed, cool until crystals precipitate, thus obtaining MNF-2, a multi-nested framework material based on dynamic B←N bonds.

7. The preparation method of MNF-2, a multi-nested framework material based on dynamic B←N bonds, as described in claim 5, is characterized in that: In step 1.1, the mass ratio of 4,4,8,8,12,12-hexamethyl-8,12-dihydro-4H-benzo[9,1]quinolrizino[3,4,5,6,7-defg]anthrazoline and N-bromosuccinimide is 1:(1.5 to 2.5). In step 1.1, the solvent is selected from one or more of chloroform, dichloromethane, toluene, methanol, and acetonitrile.

8. The preparation method of MNF-2, a multi-nested framework material based on dynamic B←N bonds as described in claim 5, is characterized in that: In step 1.3, the catalyst is selected from tetrakis(triphenylphosphine)palladium, PdCl2(dppf) and Buchwald catalyst, Pd(dtBPF)Cl2; In step 1.3, the alkali is selected from anhydrous potassium carbonate, sodium carbonate, cesium carbonate, and potassium phosphate.

9. The preparation method of MNF-2, a multi-nested framework material based on dynamic B←N bonds, as described in claim 5, is characterized in that... In step 1.3, the solvent is a mixture of tetrahydrofuran and water in a volume ratio of 2:

1.

10. The preparation method of MNF-2, a multi-nested framework material based on dynamic B←N bonds, as described in claim 5, is characterized in that: In step two, the mass ratio of monomer molecules, 1,4-phenyldiboronic acid, and 4-chlorocatechol is (1-3):(2-5):(3-8). In step two, the solvent is o-dichlorobenzene.

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