A supramolecular macrocyclic arene based on naphthalene ring and biphenyl, and a synthesis method and application thereof

Abstract

The application designs and synthesizes a supramolecular macrocyclic arene based on naphthalene ring and biphenyl, first synthesizes an intermediate molecular fragment through Friedel-Crafts reaction, and then synthesizes a novel macrocyclic arene through cyclization condensation of polyformaldehyde and the intermediate molecular. Compared with harsh conditions of traditional macrocyclic preparation, the method has the advantages of being carried out under room temperature conditions, not needing inert gas protection, simple operation, high cyclization yield and the like. Naphthalene ring is a large pi system with fluorescence properties, and various alkoxy substituted derivatives thereof can be used as a building block of a novel macrocyclic arene host, which makes the naphthalene-containing macrocyclic arene have excellent properties different from traditional macrocyclic arene hosts, and can form a non-covalent bond molecular channel for adsorbing and encapsulating xylene. The novel macrocyclic arene has good application prospects in the fields of supramolecular assembly, adsorption separation, fluorescent probe and functional materials and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of organic synthesis chemistry, and relates to a supramolecular macrocyclic arene constructed based on a naphthalene ring and a biphenyl and a synthesis method and application thereof. BACKGROUND

[0002] Since macrocyclic arene compounds have inherent molecular recognition and complexation characteristics, they have been widely used as classic tools for supramolecular chemistry research in functional materials, biological medicines, and chemical engineering since their appearance, which makes the design and preparation of new supramolecular macrocyclic host compounds with novel structures and properties an important research value in the field of supramolecular chemistry. In particular, the preparation of macrocyclic arenes with large and deep cavities, optical properties and special structures has become a hot topic at present, but the design and synthesis of such macrocyclic hosts still face certain challenges.

[0003] In recent years, with the rapid development of supramolecular chemistry and organic macrocyclic arenes, a series of new macrocyclic arenes with various functional properties and novel structures other than traditional calixarenes and pillararenes have been synthesized and reported. Naphthalene, as a large π system with good size and fluorescence properties, and its various alkoxy-substituted derivatives have become excellent building blocks for constructing new macrocyclic hosts. The synthesis of macrocyclic molecules from naphthalene has attracted more and more attention, and in 2020, a prismatic arene constructed based on 2,6-dimethoxynaphthalene was first reported. This prismatic arene structure can capture and detect aromatic volatile organic compounds. J. Am. Chem. Soc .2020, 1752−1756.) After that, Chen Chuanfeng's research group designed and synthesized a discotic arene from 2,7-dimethoxynaphthalene, which can inhibit the dynamic chiral change of the discotic arene itself after adding a chiral guest molecule. Angew. Chem .2021, 2–9.)

[0004] The appearance of each new type of macrocyclic host enriches the research of host-guest chemistry and supramolecular chemistry, but there is currently no related report on a new supramolecular receptor macrocycle constructed from a naphthalene ring and a biphenyl. Therefore, it is of important research value to design and synthesize macrocyclic arenes based on a naphthalene ring and a biphenyl and to apply them. SUMMARY

[0005] To enrich the research of host-guest chemistry and supramolecular chemistry, the present application aims to provide a macrocyclic arene compound constructed based on a naphthalene ring and a biphenyl and a synthesis method thereof.

[0006] Another object of the present application is to provide an application of the macrocyclic arene constructed based on a naphthalene ring and a biphenyl as a high-efficiency adsorption material for xylene (o-xylene, m-xylene, and p-xylene), to solve the technical problems of slow adsorption speed, low adsorption capacity, and inactivation caused by water absorption of existing xylene adsorption materials.

[0007] The supramolecular macrocyclic arene of the present application is constructed based on naphthalene ring and biphenyl, and the structural formula is as follows:

[0008] .

[0009] The supramolecular macrocyclic arene of the present application is constructed based on naphthalene ring and biphenyl, and the structural formula is as follows:

[0010] a. AlCl3 is added into dichloromethane in which alkoxy naphthalene is dissolved, and stirred at room temperature for 5-10 minutes, then slowly drop biphenyl dichlorobenzene dissolved in dichloromethane for 30-50 minutes, and stirred at room temperature for 15-30 minutes, then quenched by water, and stirred for 30-60 minutes, then washed by distilled water, and separated by column chromatography to obtain the intermediate fragment (compound 2 in the synthesis route).

[0011] In the formula, dichloromethane is the solvent, the molar ratio of biphenyl dichlorobenzene to alkoxy naphthalene is 1:6-1:7, and the molar amount of the catalyst AlCl3 is 1-1.5 times of the molar amount of biphenyl dichlorobenzene.

[0012] b. The intermediate fragment and paraformaldehyde are added into 1,2-dichloroethane, and stirred at room temperature for 5-10 minutes, then condensed into a ring by droping boron trifluoride ether, and stirred at room temperature for 5-10 minutes, then washed by distilled water, and separated by column chromatography to obtain the target product supramolecular macrocyclic arene.

[0013] In the formula, 1,2-dichloroethane is the solvent, the molar ratio of the intermediate fragment to paraformaldehyde is 1:2-1:4, and the molar amount of the catalyst boron trifluoride ether is 2 times of the molar amount of the intermediate fragment.

[0014] The synthesis route is as follows:

[0015] .

[0016] The macrocyclic arene provided by the present application has high stability by using general halogenated hydrocarbon as the reaction solvent and boron trifluoride ether as the catalyst in the ring formation reaction system, and naphthalene ring and biphenyl are used as the linking unit of the methylene bridge in the ring formation process, which opens up a new design and synthesis idea for the macrocyclic arene.

[0017] Compared with the harsh conditions of the traditional one-pot method for preparing macrocycles, the present application has the advantages of being carried out at room temperature throughout the reaction, short reaction time, no need for inert gas protection, less reaction steps, simple operation, and high ring formation yield.

[0018] The macrocyclic pillararene compound provided by the application has a central symmetric structure of a nanometer-sized electron-deficient cavity, is beneficial to adsorption, and separates similar molecules, such as arenes and cycloaliphatic compounds.

[0019] The macrocyclic arene material constructed based on a naphthalene ring and a biphenyl provided by the application has the property of forming a non-covalent molecular channel, is a high-efficiency adsorption material of a phenyl substituent such as xylene, and has potential application values in aspects such as supramolecular assembly and adsorption separation. The macrocyclic arene material constructed based on a naphthalene ring and a biphenyl can form a non-covalent molecular channel for adsorbing and encapsulating xylene, can form a 1:4 host-guest complex, 3 guest molecules are encapsulated in each macrocyclic cavity, and 1 guest molecule is outside the molecular channel. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is a nuclear magnetic resonance hydrogen spectrum of an intermediate fragment (2).

[0021] Figure 2 It is a nuclear magnetic resonance hydrogen spectrum of an intermediate fragment (2).

[0022] Figure 3 It is a mass spectrum of an intermediate fragment (2).

[0023] Figure 4 It is a nuclear magnetic resonance hydrogen spectrum of a macrocyclic arene (1).

[0024] Figure 5 It is a nuclear magnetic resonance hydrogen spectrum of a macrocyclic arene (1).

[0025] Figure 6 It is a single crystal structure diagram of a macrocyclic arene (1).

[0026] Figure 7 It is a molecular nanochannel crystal structure diagram of a macrocyclic arene (1).

[0027] Figure 8 It is a macrocyclic arene molecular channel adsorption and encapsulation xylene eutectic structure based on a naphthalene ring and a biphenyl.

[0028] Figure 9 It is a hydrogen spectrum displacement comparison of a macrocyclic arene host (a), o-xylene (c), and a macrocyclic arene (b) after adsorbing o-xylene.

[0029] Figure 10 It is a hydrogen spectrum displacement comparison of a macrocyclic arene host (a), m-xylene (c), and a macrocyclic arene (b) after adsorbing m-xylene.

[0030] Figure 11 It is a hydrogen spectrum displacement comparison of a macrocyclic arene host (a), p-xylene (c), and a macrocyclic arene (b) after adsorbing p-xylene.

[0031] Figure 12 Figure 8 shows the time dependence of the solid-gas adsorption of xylene vapor on macrocyclic arenes at 293 K. DETAILED DESCRIPTION

[0032] The following examples further illustrate the specific embodiments of the present application. The instruments and reagents used are commercially available and commonly used in the art unless otherwise stated.

[0033] Example 1. Synthesis of supramolecular macrocyclic arenes

[0034] a. Aluminum trichloride (191.12 mg, 1.43 mmol) was added into 2,6-dimethoxynaphthalene (1.35 g, 7.17 mmol) dissolved in dichloromethane (150 mL), and stirred at room temperature for 5-10 minutes. Then diphenyldichlorobenzene (300 mg, 1.19 mmol) dissolved in dichloromethane (100 mL) was added dropwise slowly for 30-50 minutes. After stirring at room temperature for 15-30 minutes, the reaction was quenched by water, and stirred for 30-60 minutes. The mixture was washed with distilled water, and extracted by CH2Cl2 / H2O system. The white solid product intermediate fragment (compound 2, 460.8 mg, 34.13%) was obtained by column chromatography (petroleum ether: ethyl acetate = 15:1, v / v).

[0035] 1 H NMR (400 MHz, Chloroform-d) δ 7.83 (d, J = 10.4 Hz, 2H), 7.69 (d, J = 9.0 Hz, 2H), 7.36 (d, J = 8.4 Hz, 4H), 7.31 (d, J = 9.0 Hz, 2H), 7.18 (d, J = 8.3 Hz, 4H), 7.10 (d, J = 8.2 Hz, 4H), 4.46 (s, 4H), 3.92 (s, 6H), 3.89 (s, 6H). 13 C NMR (150 MHz, Chloroform-d) δ 139.96, 138.51, 128.77, 128.49, 126.85, 125.42, 122.04, 114.34, 56.89, 55.26, 30.34. Molecular weight simulation value: m / z 554.2457, high resolution mass spectrometry test value: m / z 554.2434.

[0036]

[0037] b. The intermediate fragment (332.8 mg, 0.6 mmol) was added to a suitable amount of 1,2-dichloroethane (50 mL) and stirred at room temperature for 5-10 min, then trifluoroboron ether (0.5 mL) was added dropwise to condense the ring, stirred at room temperature for 5-10 min, washed with distilled water, extracted with CH2Cl2 / H2O system, then separated by column chromatography (petroleum ether: ethyl acetate = 2:1, v / v) to obtain white solid product macrocyclic arene (180.4 mg, 54.2%).

[0038] 1 H NMR (400 MHz, Chloroform-d): δ 8.28 (s, 4H), 7.83 (d, J = 9.4 Hz, 4H), 7.30 (d, J = 9.4 Hz, 4H), 7.27 (s, 4H), 7.25 (s, 4H), 7.16-7.08 (m, 12H), 4.90 (s, 4H), 4.42 (s, 8H), 4.10 (s, 12H), 3.80 (s, 12H). 13 C NMR (150 MHz, Chloroform-d): δ 152.94, 152.10, 138.44, 130.01, 129.40, 126.84, 125.36, 124.53, 123.68, 121.40, 113.66, 57.12, 56.53, 30.29.

[0039]

[0040] The single crystal culture of macrocyclic arenes constructed based on naphthalene rings and biphenyl was carried out as follows: 6 mg of pure macrocyclic arene was placed in a 4 mL capacity glass vial, 2.5 mL of analytical pure dichloromethane was added to dissolve it into a colorless transparent solution, the vial was placed in a 15 mL capacity glass bottle containing 4 mL of analytical pure n-hexane, the cap was tightened, and the single crystal culture was carried out by slowly evaporating the poor solvent into the good solvent system, and the glass bottle was placed in a cool place, and the glass bottle should not be shaken during observation.

[0041] The single crystal structure of macrocyclic arenes constructed based on naphthalene rings and biphenyl is as shown in Figure 6 The macrocyclic cavity is like a "football". The long axis of the cavity is 17.52 Å, and the short axis is 9.97 Å. The whole single crystal has central symmetry characteristics, but each unit connected by methylene bridges is staggered with each other and not in the same plane. The packing structure of the crystal has the characteristics of being able to form a non-covalent bond molecular channel due to the C−H···π interaction between the methyl groups of adjacent two units and the naphthalene ring (as shown in Figure 7), which has potential application value in supermolecular assembly, adsorption separation, etc. Figure 8 The three xylene co-crystal structures are encapsulated by the non-covalent molecular tube of the macrocyclic arene constructed based on a naphthalene ring and a biphenyl, to form a 1:4 host-guest complex, and each cavity of the macrocyclic arene encapsulates 3 guest molecules, and 1 guest molecule is outside the molecular tube.

[0042] Figures 9-11 The macrocyclic arene is a host, the xylene is a guest, and the hydrogen spectrum displacement of the macrocyclic host after adsorbing the xylene is compared, and the peaks of o-xylene, m-xylene and p-xylene in the spectrum show high field displacement, indicating that the three isomers are all located in the cavity of the macrocyclic arene host in the solution.

[0043] Example 2: Supramolecular macrocyclic arene adsorbing xylene

[0044] The gas phase independent experiment of the macrocyclic arene constructed based on a naphthalene ring and a biphenyl efficiently adsorbing xylene vapor, 5.00 mL open vials containing 5.00 mg of activated macrocyclic adsorbent are respectively placed in 20.00 mL sealed vials containing 1.00 mL of o-xylene, m-xylene and p-xylene. The relative absorption of the activated macrocyclic adsorbent to the three xylene isomers is measured by the molar amount of adsorbed xylene vapor and the molar amount of released vapor by heating the crystal. Before measurement, the crystal is heated at 60 DEG C for half an hour to remove the physically adsorbed vapor on the surface. Figure 12 The solid-gas adsorption cycle experiment of xylene vapor on the macrocyclic arene at 293 K is a curve changing with time, and it takes about 4 hours for the crystal to adsorb xylene to reach the saturation point. At the saturation point, according to the experimental results, the molar ratio of the macrocyclic arene adsorbing xylene is 1:3, which is consistent with the characterization results of the crystal. After being used repeatedly for 5 times, the adsorption of xylene does not change obviously, indicating that the adsorption material prepared by using the macrocyclic arene compound in the application has high recycling rate.

Claims

1. Use of supramolecular macrocyclic arenes based on naphthalene and biphenyl building blocks for the adsorption of xylene, characterized in that: The supermolecular macrocycle arene based on naphthalene ring and biphenyl, and the structural formula is: The macrocyclic cavity of the supramolecular macrocycle aryl hydrocarbon is like an "American football", with a long axis of 17.52 Å and a short axis of 9.97 Å. The whole single crystal has a central symmetry characteristic, but each unit connected by a methylene bridge is staggered with each other and not in the same plane. The packing structure of the crystal has the characteristic of being able to form a non-covalent molecular channel due to the C−H···π interaction force between the methyl group and the naphthalene ring of the adjacent two units. The macrocycle aryl hydrocarbon non-covalent molecular channel adsorbs and encapsulates the xylene co-crystal structure based on the naphthalene ring and the biphenyl to form a 1:4 host-guest complex. Each macrocyclic cavity encapsulates 3 xylene guest molecules, and 1 xylene guest molecule is outside the molecular channel.

2. Use according to claim 1, characterized in that: The xylene is o-xylene, m-xylene or p-xylene.

3. Use according to claim 1, characterized in that: The synthesis method of the supermolecular macrocycle arene based on naphthalene ring and biphenyl comprises the following steps: a. To the dichloromethane dissolved with alkyloxy naphthalene, add aluminum chloride, after stirring at room temperature for 5-10 minutes, slowly drop the biphenyl dichlorobenzene dissolved in dichloromethane, after stirring at room temperature for 15-30 minutes, quench the reaction with water, continue stirring for 30-60 minutes, after washing with distilled water, separate the product by column chromatography to obtain the intermediate fragment, the structural formula of the intermediate fragment is: ; b. The intermediate fragment and paraformaldehyde are added into 1,2-dichloroethane, and after stirring at room temperature for 5-10 minutes, boron trifluoride etherate is added dropwise to condense into a ring, and stirring is carried out at room temperature for 5-10 minutes; after washing with distilled water, the product is separated by column chromatography to obtain the supermolecular macrocycle arene based on naphthalene ring and biphenyl.

4. The use according to claim 2, characterized in that: The molar ratio of the biphenyl dichlorobenzene to the alkoxy naphthalene in step a is 1:6-1:

7.

5. The use according to claim 2, wherein: The molar amount of the aluminum trichloride in step a is 1-1.5 times the molar amount of the biphenyl dichlorobenzene.

6. The use according to claim 2, characterized in that: The molar ratio of the intermediate fragment to the paraformaldehyde in step b is 1:2-1:

4.

7. The use according to claim 2, wherein: The molar amount of the boron trifluoride etherate in step b is 2 times the molar amount of the intermediate fragment.

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