A hetero[3]aromatic macrocyclic compound and its preparation method and application

Abstract

The present invention discloses a hetero[3]aromatic macrocyclic compound and a preparation method and application thereof. The hetero[3]aromatic macrocyclic compound is prepared by integrating ethoxybiphenyl and methoxyphenol on a ring skeleton and introducing a hydroxyl functional group into the structure, thereby having the performance of effectively capturing elemental iodine, thereby achieving saturated adsorption of iodine in a relatively short time, and completely releasing the captured iodine within 100 minutes at a temperature of 70 to 100° C., and having a recycling effect in which the performance remains substantially unchanged after being recycled 10 times; in addition, from the perspective of reactants, temperature, time and reaction solvent, the preparation method of the hetero[3]aromatic macrocyclic compound disclosed in the present invention is simple and low in cost, and fully meets the industrial demand for elemental iodine adsorption.

Description

Technical Field

[0001] The invention relates to the field of supramolecular chemistry, and in particular to a heteroaromatic macrocyclic compound, a synthesis method thereof and an application thereof as an iodine adsorption material. Background Art

[0002] Macrocyclic molecules are one of the important structural elements of supramolecular chemistry. The development of new macrocyclic molecules is an important source for innovating supramolecular systems and expanding functional applications. Due to their unique topological structure and excellent host-guest recognition ability, supramolecular macrocyclic receptors provide many opportunities for potential applications in the fields of green separation and pollution control as selective adsorption materials, and have long been an important goal of supramolecular chemistry research.

[0003] J.Am.Chem.Soc.2017,139,15320-15323 discloses a pillar aromatic macrocyclic iodine adsorption material. The pillar aromatic macrocyclic has a single building unit and has the function of capturing iodine. However, since it only has an iodine capture capacity of 20wt% and its saturated adsorption of iodine requires at least 120min, the adsorption efficiency and adsorption capacity of iodine by the pillar aromatic macrocyclic are not ideal. In addition, considering the reactants, temperature, time and reaction solvent, its synthesis process is relatively complicated. Moreover, the effect of repeated activation and reuse is not ideal. Therefore, the pillar aromatic macrocyclic disclosed in the above document as an iodine adsorption material does not have practical industrial application value. Summary of the invention

[0004] In view of this, the present invention provides a hetero[3]arene macrocyclic compound to solve the problem that the existing pillar aromatic macrocyclic iodine adsorption materials have low adsorption efficiency and adsorption capacity, unsatisfactory recycling effect, and are not suitable for industrial application.

[0005] In addition, the present invention also provides a method for preparing the hetero[3]aromatic macrocyclic compound and its application as an elemental iodine adsorption material.

[0006] In the first aspect, the hetero[3]arene macrocyclic compound has the following structural formula:

[0007]

[0008] In a second aspect, a method for preparing the hetero[3]arene macrocyclic compound of the first aspect comprises:

[0009] 4,4'-diethoxybiphenyl, 3,4,5-trimethoxyphenol and paraformaldehyde are dissolved in an organic solvent at a molar ratio of 1:2:2, trifluoroacetic acid is added to catalyze the reaction to obtain a reaction solution, and the reaction solution is separated by column chromatography to obtain a hetero[3]aromatic macrocyclic compound.

[0010] In the present disclosure and possible embodiments, the reaction is carried out under stirring at a temperature of 50 to 60° C. After reacting for 15 to 60 minutes, the stirring is stopped and the mixture is cooled to room temperature, and a saturated sodium bicarbonate solution is added to quench the reaction.

[0011] In the present disclosure and possible embodiments, the method for preparing 4,4'-diethoxybiphenyl comprises:

[0012] N,N-dimethylformamide is added to a mixture of ethyl bromide, 4,4'-dihydroxybiphenyl and potassium carbonate at a molar ratio of 10:1:3, and the mixture is stirred at room temperature to react, and the reaction product is recrystallized to obtain the 4,4'-diethoxybiphenyl.

[0013] In the present disclosure and possible embodiments, the room temperature is 10-30° C., the reaction time is 4-6 hours; water is added to the reaction product to perform the recrystallization;

[0014] The recrystallized product is filtered, washed with water, and then vacuum dried at 40-50° C. to obtain the 4,4′-diethoxybiphenyl.

[0015] In the present disclosure and possible embodiments, the column chromatography eluent is petroleum ether or dichloromethane.

[0016] In the present disclosure and possible embodiments, the organic solvent is chloroform.

[0017] In a third aspect, the hetero[3]aromatic macrocyclic compound described in the first aspect is used as an iodine adsorption material.

[0018] In the present disclosure and possible embodiments, the hetero[3]arene macrocyclic compound saturated with iodine adsorption is heated to desorb the iodine, and the heating temperature is 70 to 100° C.;

[0019] The hetero[3]arene macrocyclic compounds after iodine desorption are recycled for iodine adsorption.

[0020] In the present disclosure and possible embodiments, the number of cycles is at least 10 times.

[0021] The present invention has the following beneficial effects:

[0022] The hetero[3]arene macrocyclic compound of the present invention is a hybrid macrocyclic compound composed of different structural units in terms of product structure. By integrating ethoxybiphenyl and methoxyphenol on a ring skeleton, the structural cavity of the supramolecular macrocyclic compound is effectively broadened. A larger structural cavity is bound to adsorb larger molecules, thereby facilitating the removal of pollutants such as dyes in water. In addition, a hydroxyl functional group is introduced into the structure of the hetero[3]arene macrocyclic compound, which can achieve effective capture of iodine, and can achieve an iodine capture amount of 2 g / g (66 wt%).

[0023] From the aspect of preparation method, the raw materials of the hetero[3]aromatic macrocyclic compound disclosed in the present invention are cheap and easy to obtain, and 4,4'-diethoxybiphenyl can be obtained by reaction at room temperature and normal pressure, and the reaction conditions are simple; for the synthesis of hetero[3]aromatic macrocyclic compound, if 4,4'-diethoxybiphenyl is directly purchased, the final product hetero[3]aromatic macrocyclic compound can be obtained in only 15 minutes, so the synthesis process of the hetero[3]aromatic macrocyclic compound provided in the present invention is simple and low in cost, and has strong industrial applicability;

[0024] From the perspective of product performance, the hetero[3]arene macrocyclic compound disclosed herein can achieve saturated adsorption of iodine in a relatively short period of time (30 minutes), and the hetero[3]arene macrocyclic compound disclosed herein can completely release the captured iodine within 100 minutes at a temperature of 70 to 100° C., which is conducive to the recycling of the hetero[3]arene macrocyclic compound, and achieves a recycling effect in which the performance remains substantially unchanged after 10 cycles of use;

[0025] Therefore, the hetero[3]aromatic macrocyclic compound disclosed in the present invention has the characteristics of high adsorption rate, large adsorption capacity, repeated recycling and maintaining adsorption performance as an iodine adsorption material, which fully meets the industrial demand for iodine adsorption. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0027] Figure 1 is the H NMR spectrum of the hetero[3]arene macrocyclic compound obtained in Example 1;

[0028] Figure 2 is the carbon spectrum of the hetero[3]arene macrocyclic compound obtained in Example 1;

[0029] Figure 3 The mass spectrum of the hetero[3]arene macrocyclic compound obtained in Example 1;

[0030] Figure 4 is the powder X-ray diffraction (PXRD) pattern of the hetero[3]arene macrocyclic compound crystal;

[0031] Figure 5 Thermogravimetric (TG) curve of the hetero[3]arene macrocyclic compound obtained in Example 1;

[0032] Figure 6 The single crystal structure of the hetero[3]arene macrocyclic compound obtained in Example 1;

[0033] Figure 7 The PXRD pattern of the hetero[3]arene macrocyclic compound obtained in Example 1 after capturing iodine;

[0034] Figure 8 TG curves of the hetero[3]arene macrocyclic compound obtained in Example 1 and after capturing iodine;

[0035] Fig. 9 The single crystal structure of the hetero[3]arene macrocyclic compound obtained in Example 1 after capturing iodine;

[0036] Fig.10 This is a cyclic experiment of the hetero[3]arene macrocyclic compound obtained in Example 1 capturing iodine. DETAILED DESCRIPTION

[0037] The present disclosure is described below based on embodiments, but it is worth noting that the present disclosure is not limited to these embodiments. In the detailed description of the present disclosure below, some specific details are described in detail. However, for the parts that are not described in detail, those skilled in the art can also fully understand the present disclosure.

[0038] In addition, those skilled in the art should understand that the drawings are provided only to illustrate the purpose, features and advantages of the present disclosure, and the drawings are not actually drawn to scale. At the same time, unless the context clearly requires, the words "include", "comprise" and the like in the entire specification and claims should be interpreted as inclusive rather than exclusive or exhaustive; that is, "including but not limited to" meaning.

[0039] The hetero[3]arene macrocyclic compound provided by the present disclosure has the following structural formula:

[0040]

[0041] It can be seen from the above structural formula that the hetero[3]aromatic macrocyclic compound is a hybrid macrocyclic compound composed of different structural units, that is, ethoxybiphenyl and methoxyphenol are integrated into a ring skeleton, which can effectively broaden the structural cavity of the supramolecular macrocyclic compound. A larger structural cavity is bound to adsorb larger molecules, which is beneficial to the removal of pollutants such as dyes in water.

[0042] In addition, the hetero[3]arene macrocyclic compound disclosed in the present invention introduces a hydroxyl functional group, which can achieve effective capture of iodine, thereby capturing more iodine. According to tests conducted by the applicant, the iodine capture amount can reach 2 g / g (66 wt%).

[0043] Furthermore, compared with the heteroaromatic hydrocarbons disclosed in J.Am.Chem.Soc.2020,142,2228-2232, on a similar macrocyclic skeleton, the hydroxyl group can enable the heteroaromatic hydrocarbons to have the ability to adsorb iodine, and is no longer limited to the separation of benzene and cyclohexane. Therefore, the hetero[3]aromatic macrocyclic compounds disclosed in the present invention have broader application prospects and can show outstanding potential in the fields of host-guest recognition, pollutant adsorption, and temperament color change, opening up a new research direction for supramolecular chemistry.

[0044] The present disclosure further illustrates the preparation method and application of the hetero[3]arene macrocyclic compound of the present invention through examples. The test methods described in the following examples are conventional methods unless otherwise specified; the reagents and materials described are all commercially available unless otherwise specified.

[0045] First, the reaction equation for synthesizing the hetero[3]arene is as follows:

[0046]

[0047] According to the above reaction equation, the embodiment of the present disclosure adopts the following steps to prepare hetero[3]arene, and the specific steps are as follows:

[0048] The first step of the reaction: put ethyl bromide, 4,4'-dihydroxybiphenyl (CAS number: 92-88-6, sales platform: Aladdin, Anaiji, etc.) and potassium carbonate in a molar ratio of 10:1:3 into a reaction container (such as a round-bottom flask), add N,N-dimethylformamide, and stir the reaction at room temperature (10-30°C) for 4-6 hours; after the reaction is completed, pour the reaction solution into water for recrystallization and filtration, then wash with water 2-3 times, put it into a vacuum drying oven and heat it to 40-50°C to dry it to obtain the intermediate product 4,4'-diethoxybiphenyl;

[0049] The second step reaction: 4,4'-diethoxybiphenyl, 3,4,5-trimethoxyphenol and paraformaldehyde in a molar ratio of 1:2:2 are dissolved in chloroform, trifluoroacetic acid is added during stirring at room temperature to catalyze the reaction, and then heated to 50-60°C and stirred for 15-60 minutes until the reaction is complete. After the reaction product is cooled to room temperature, a saturated sodium bicarbonate solution is added to quench the reaction, and after separation, the hetero[3]aromatic hydrocarbons are separated by column chromatography; the column chromatography eluent can be petroleum ether or dichloromethane, but is not limited thereto.

[0050] The 4,4'-diethoxybiphenyl used in the embodiment of the present disclosure to prepare hetero[3]aromatic macrocyclic compounds can also be purchased from a sales platform, such as the adamas platform, CAS number: 7168-54-9, but because it is expensive, the present disclosure adopts a homemade method to obtain the 4,4'-diethoxybiphenyl; it can be seen from the content of the above first step reaction that the method of preparing 4,4'-diethoxybiphenyl in the present disclosure has easy-to-obtain raw materials, the reaction conditions are only room temperature and normal pressure, and the post-treatment process such as recrystallization is simple and easy to operate, so it can effectively reduce the cost of preparing hetero[3]aromatic macrocyclic compounds.

[0051] Example 1

[0052] 1. Preparation of hetero[3]arene macrocyclic compounds

[0053] The first step of the reaction: 7.50 mL of ethyl bromide, 1.89 g of 4,4'-dihydroxybiphenyl and 6.50 g of potassium carbonate were placed in a round-bottom flask, and 50.0 mL of N,N-dimethylformamide was added, and the mixture was stirred at 25°C for 5 hours. After the reaction was completed, the reaction solution was poured into water for recrystallization, filtered, and then washed with water for 3 times. The mixture was placed in a vacuum drying oven and heated to 40-50°C, and then dried to obtain 4,4'-diethoxybiphenyl; the yield of the 4,4'-diethoxybiphenyl was 98% after testing.

[0054] The second step reaction: 1.21g of 4,4'-diethoxybiphenyl, 1.82g of 3,4,5-trimethoxyphenol and 0.900g of polyformaldehyde were dissolved in 80mL of chloroform, and 10.0mL of trifluoroacetic acid was added as a reaction catalyst during stirring at room temperature, and then heated to 50-60°C and stirred and reacted. The reaction was completed after stirring for 15 minutes. After the reactants were cooled to room temperature, 30.0mL of saturated sodium bicarbonate solution was added to quench the reaction. After separation, the hetero[3]aromatic macrocyclic compound was obtained by column chromatography, and the eluent was dichloromethane. The yield of the hetero[3]aromatic macrocyclic compound was tested to be 50%.

[0055] The characterization data of the hetero[3]arene macrocyclic compound prepared in Example 1 are as follows:

[0056] 1H NMR (500MHz, chloroform-d, 293K) δ (ppm): 7.20 (d, J = 10.6Hz, 2H), 6.78 (s, 2H), 6.19 (s, 2H), 5.52 (s, 2H), 4.18 (d, J = 16.9Hz, 2H), 4.14 (s, 2H), 4.09 (t, J = 7.0Hz, 4H), 4.03 (s, 6H), 3.79 (s, 6H), 3.69 (d, J = 16.8Hz, 2H), 3.56 (s, 6H), 1.46 (t, J = 6.9Hz, 6H). 13 C NMR (126MHz, chloroform-d, 293K) δ (ppm): 155.84, 151.63, 150.11, 149.05, 140.24, 132.94, 128.41, 127.17, 123.39, 116.73, 113.24, 110.55, 63.63, 61.81, 61.12, 61.08, 23.16, 18.08, 15.06. High resolution mass spectrometry value m / z: 669.2667, corresponding to [hetero[3]arene-H]-. Melting range: 299.5~301.9℃.

[0057] Figure 1-Figure 3 The NMR hydrogen spectrum, carbon spectrum and mass spectrum of the hetero[3]aromatic macrocyclic compound obtained in Example 1 are shown in Figure 1. Figure 4 As shown in Figure 2, the aromatic macrocyclic compound has good crystallinity. The TG test results of the hetero[3]aromatic macrocyclic compound of Example 1 are as follows: Figure 5 As shown, the aromatic macrocyclic compound has good stability. The single crystal structure and related parameters of the hetero[3]aromatic macrocyclic compound of Example 1 are shown in Figure 6 As shown, the aromatic macrocyclic compound has a good crystal structure.

[0058] 2. Iodine adsorption experiment

[0059] 5 mg of the hetero[3]arene macrocyclic compound of Example 1 was placed in a 4 mL vial, which was then placed in a 20 mL vial containing 5 g of iodine, and the whole was placed in an oven at 60° C. The 4 mL vial was taken out and weighed every two minutes to calculate the iodine adsorption amount.

[0060] The test showed that the amount of iodine adsorbed by the hetero[3]aromatic macrocyclic compound of Example 1 was 2 g / g (66 wt%), and the time was 30 min.

[0061] 5 mg of hetero[3]arene macrocyclic compound dried at 150°C for 4 h was placed in a 4 mL small glass bottle, the small glass bottle was placed in a 10 mL large glass bottle, about 3 g of iodine was placed in the 10 mL large glass bottle, and heated in an oven at 70°C for 30 min.

[0062] Through Figure 7 As shown, it is proved that the hetero[3]arene macrocyclic compound of Example 1 of the present disclosure has captured iodine. The hetero[3]arene macrocyclic compound that has captured iodine was subjected to TG detection, and the result is as follows Figure 8 As shown, the mass of iodine captured by the hetero[3]arene macrocyclic compound can be obtained by analysis. In addition, the hetero[3]arene macrocyclic compound that captured iodine was subjected to single crystal testing, such as Fig. 9 As shown, the overall structure of matter is intuitively shown.

[0063] 3. Iodine desorption experiment

[0064] The iodine-saturated hetero[3]arene macrocyclic compound was placed on a heating table, heated at 70°C, and weighed every ten minutes to calculate the amount of iodine desorption.

[0065] The amount of iodine adsorbed and desorbed from the saturated hetero[3]aromatic macrocyclic compound in Example 1 was tested to be 2 g / g (66 wt%), and the time was 100 min.

[0066] 4. Iodine adsorption cycle experiment

[0067] 5 mg of hetero[3]arene macrocyclic compound was placed in a 4 mL small glass bottle, and the small glass bottle was placed in a 20 mL large glass bottle with 5 g of iodine added, and the whole was placed in a 60°C oven for heating. The 4 mL small glass bottle was taken out and weighed every two minutes to calculate the iodine adsorption amount. The hetero[3]arene saturated with iodine adsorption was then placed on a heating table, heated at 70°C, and weighed every ten minutes to calculate the iodine desorption amount; and so on. After testing Example 1, the hetero[3]arene macrocyclic compound can undergo at least 10 iodine adsorption cycles and maintain performance not less than 96% of the original.

[0068] like Fig.10 As shown, the hetero[3]arene macrocyclic compound of Example 1 of the present disclosure can capture iodine for at least 10 cycles without substantially losing performance.

[0069] It can be seen from the description of Example 1 above that in terms of the preparation method, the raw materials of the hetero[3]aromatic macrocyclic compounds disclosed in the present invention are cheap and easy to obtain (4,4'-dihydroxybiphenyl, CAS No.: 92-88-6, sales platform: Aladdin, Anaiji, etc.), and the intermediate product (4,4'-diethoxybiphenyl) can be obtained by reaction at room temperature and normal pressure, and the reaction conditions are simple. For the synthesis of hetero[3]aromatic macrocyclic compounds, if the intermediate product 4,4'-diethoxybiphenyl (CAS No.: 7168-54-9, sales platform: exploration platform adamas) is purchased, the final product hetero[3]aromatic macrocyclic compounds can be obtained in only 15 minutes. From the perspective of reactants, temperature, time and reaction solvent, the synthesis process of hetero[3]aromatic macrocyclic compounds is relatively simple and the synthesis cost is low, the reaction conditions are mild, fast, the conversion rate is high, and it can be industrialized.

[0070] Secondly, from the performance point of view, the hetero[3]arene macrocyclic compound disclosed in the present invention can achieve saturated adsorption of iodine in a relatively short time (30 minutes), while the literature of the background technology requires at least 120 minutes. In addition, the hetero[3]arene macrocyclic compound disclosed in the present invention can completely release the captured iodine within 100 minutes at a temperature of 70 to 100° C., which is very conducive to the recycling of the hetero[3]arene macrocyclic compound. After testing, the hetero[3]arene macrocyclic compound disclosed in the present invention can be recycled 10 times with basically unchanged performance.

[0071] The hetero[3]aromatic macrocyclic compounds synthesized by the present invention can efficiently capture elemental iodine, thereby achieving the purpose of removing radioactive pollutants; and the hetero[3]aromatic macrocyclic compounds synthesized by the present invention have potential application prospects in the purification of petrochemical raw materials, etc.

[0072] The above-described embodiments are only embodiments of the present disclosure, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the present disclosure. It should be noted that, for a person of ordinary skill in the art, without departing from the concept of the present disclosure, several variations, equivalent substitutions, improvements, etc. may be made, all of which fall within the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure shall be subject to the attached claims.

Claims

1. A hetero[3]arene macrocyclic compound, characterized in that The structural formula of the compound is as follows: In the formula: Me represents a methyl group, and Et represents an ethyl group.

2. The method for preparing the hetero[3]arene macrocyclic compound according to claim 1, characterized in that: include: 4,4'-diethoxybiphenyl, 3,4,5-trimethoxyphenol and paraformaldehyde are dissolved in an organic solvent at a molar ratio of 1:2:2, trifluoroacetic acid is added to catalyze the reaction to obtain a reaction solution, and the reaction solution is separated by column chromatography to obtain a hetero[3]aromatic macrocyclic compound.

3. The method for preparing the hetero[3]arene macrocyclic compound according to claim 2, characterized in that: The reaction is carried out under stirring at a temperature of 50-60° C. After reacting for 15-60 minutes, the stirring is stopped and the mixture is cooled to room temperature. A saturated sodium bicarbonate solution is added to quench the reaction.

4. The method for preparing the hetero[3]arene macrocyclic compound according to claim 3, characterized in that: The preparation method of 4,4'-diethoxybiphenyl comprises: N,N-dimethylformamide is added to a mixture of ethyl bromide, 4,4'-dihydroxybiphenyl and potassium carbonate at a molar ratio of 10:1:3, and the mixture is stirred at room temperature to react, and the reaction product is recrystallized to obtain the 4,4'-diethoxybiphenyl.

5. The method for preparing the hetero[3]arene macrocyclic compound according to claim 4, characterized in that: The stirring reaction time at room temperature is 4 to 6 hours; water is added to the reaction product to perform the recrystallization; The recrystallized product is filtered, washed with water, and then vacuum dried at 40-50° C. to obtain the 4,4′-diethoxybiphenyl.

6. The method for preparing the hetero[3]arene macrocyclic compound according to any one of claims 3 to 5, characterized in that: The column chromatography eluent is petroleum ether or dichloromethane.

7. The method for preparing the hetero[3]arene macrocyclic compound according to claim 4, characterized in that: The organic solvent is chloroform.

8. Use of the hetero[3]arene macrocyclic compound of claim 1 as an iodine adsorption material.

9. The use of the hetero[3]arene macrocyclic compound according to claim 8 as an iodine adsorption material, characterized in that: Heating the hetero[3]arene macrocyclic compound saturated with iodine adsorption to desorb the iodine, wherein the heating temperature is 70 to 100° C.; The hetero[3]arene macrocyclic compounds after iodine desorption are recycled for iodine adsorption.

10. Use of the hetero[3]arene macrocyclic compound according to claim 9 as an iodine element adsorption material, characterized in that: The number of cycles is at least 10 times.

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