A compound, preparation method and application thereof

Abstract

The present application relates to the field of membrane separation, in particular to a kind of compound and its preparation method and application.The structural formula of the compound described in the present application is as shown in the following formula (I) and formula (II);The compound can be used as the precursor of hydrogel;By inserting hydrophilic and hydrophobic channels, the traditional hydrogel structure is topologically transformed, the lipophilicity of the surface of hydrogel is optimized, the homogeneous solution is destroyed by using the hybrid of hydrophilic and hydrophobic channels, and is converted into a heterogeneous mixed system, which provides a feasible solution for solving the separation of homogeneous mixed system.The structural formula of R is as shown in formula (II).

Description

Technical Field

[0001] This invention relates to the field of membrane separation, and more particularly to a compound, its preparation method, and its application. Background Technology

[0002] With the large-scale extraction and widespread use of mineral oil, the global energy crisis is intensifying. Given that oil is a non-renewable resource, improving the utilization rate of its components can alleviate energy shortages and further increase the economic value of downstream products (Nature 2016, 532, 435–437). Distillation is the main method of crude oil refining, consuming over 70% of the total energy in petrochemical production. However, it is difficult to effectively separate mixtures with similar physicochemical properties (Chem. Soc. Rev. 2020, 49, 5359-5406).

[0003] Compared to traditional heat treatment methods, membrane separation is a novel, highly efficient, and energy-saving separation technology with advantages such as being environmentally friendly, having high separation efficiency, being simple to operate, and being safe (Science 2022, 377, 1555-1561). Among various membrane materials, hydrogels cross-linked by hydrophilic networks possess excellent water absorption, environmental compatibility, and dynamic mechanical properties, making them ideal materials for oil-water separation and water purification. For example, Jiang Lei et al. reported a hydrogel coating with superhydrophilicity and underwater superoleophobicity. Using polyacrylamide (PAM) as the hydrogel matrix and N,N'-methylenebisacrylamide as the cross-linking agent, the resulting gel was coated on a stainless steel mesh. Utilizing the underwater superoleophobicity of the hydrogel coating, oily components could be isolated above the steel mesh, successfully achieving the separation of oil / water mixtures, including gasoline, diesel, ethane, and petroleum ether, as well as organic solvent / water mixtures (Adv. Mater. 2011, 23, 4270-4273). Another example is the flexible supramolecular framework reported by Wu Lixin et al., which is composed of metal cation salts, cationic columnar aromatics and bridging guests. When the supramolecular gel assembled by this layered framework is wetted by a fluid, the surface properties of the gel membrane can be rapidly changed. Thus, the hydrogel membrane can be used for the rapid separation of oil-water and immiscible liquids, as well as the in-situ reversible conversion of the separated liquid (Nat. Commun. 2020, 11, 425).

[0004] Although topological gel frameworks have led to the development of a series of hydrogel materials, separation remains difficult for miscible systems with similar physicochemical properties. Furthermore, the wetting of the membrane surface by miscibles typically results in high surface energy, hindering the rapid penetration of active materials. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a compound that can be used as a precursor of hydrogels. By interpenetrating hydrophilic and hydrophobic channels, it can topologically transform the traditional hydrogel structure, optimize the lipophilicity of the hydrogel surface, and use the hybridization of hydrophilic and hydrophobic channels to disrupt the homogeneous solution and transform it into a heterogeneous mixed system, thus providing a feasible solution for the separation of homogeneous mixed systems.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] In a first aspect, the present invention provides a compound having the structural formula shown in the following formula (Ⅰ):

[0008]

[0009] The structural formula of R is shown in equation (Ⅱ):

[0010]

[0011] The compound has a V-shaped molecular structure with the benzene rings at both ends of the intermediate pyridine forming a 120° angle. The V-shaped molecule features rigid benzene rings of adjacent molecules stacked vertically via π-π interactions and synergistically linked by hydrogen bonds, developing into a block copolymer assembly to prepare a one-dimensional tubular gel precursor compound. To maintain structural stability during gelation, a proton acceptor pyridine is introduced into the central region of the rigid structure, and proton donors such as hydroxyl groups are connected to both sides of the backbone. This fosters hydrogen bond recognition during multi-level assembly, inducing synergistic assembly through hydrogen bonds and π-π interactions, enabling the construction of multi-dimensional, multi-level perforated gel membranes.

[0012] In the aqueous solution system, the precursor molecules of the gel contain both hydrophilic and hydrophobic components. Due to hydrophobic interactions, the benzene rings tend to stack, forming nanotubes with hydrophobic cavities inside and hydrophilic polyethylene glycol (PEG) surrounding them. At low concentrations, the precursor V-type molecules self-assemble in the aqueous solution to form helical tubes. XRD analysis shows that the helical tubes have a total of 10 layers of microstructure. The V-type molecules stack 10 layers to form a repeating unit, and further extension in one dimension forms nano-helical tubes. When the concentration of V-type molecules in the aqueous solution is gradually increased to the concentration of this invention (4-6 wt%), the concentration of helical tubes increases, and they further aggregate to form a gel. The cavities inside the helical tubes in the gel are hydrophobic, while the aggregated tubes are composed of hydrophilic PEG branches, forming hydrophilic channels between the tubes. Thus, the gel as a whole is interlaced with hydrophobic internal tubular cavities and hydrophilic external channels.

[0013] Secondly, the present invention provides a method for preparing the above-mentioned compound, comprising the following steps:

[0014] (1) 2,6-Dibromo,4-nitropyridine reacts with dendritic polyethylene glycol tetra-branched chains in the presence of an alkaline catalyst to generate intermediate A through a substitution reaction;

[0015] (2) Intermediate A obtained in step (1) is reacted with 4-(trimethylsilane)biphenylboronic acid via a Suzuki coupling reaction under the action of a catalyst to generate intermediate B;

[0016] (3) After reacting intermediate B obtained in step (2) with an iodizing agent, sodium thiosulfate is added and stirred to obtain intermediate C;

[0017] (4) The intermediate C obtained in step (3) is reacted with 4-hydroxybiphenylboronic acid through a Suzuki coupling reaction under the action of a catalyst to generate a V-type molecule;

[0018] The structure of intermediate A is shown in formula (III); the structure of intermediate B is shown in formula (IV); the structure of intermediate C is shown in formula (V):

[0019]

[0020] Step (1) Using nonylbenzene folded at 120° as a rigid backbone, connect the four branches of dendritic polyethylene glycol through a ferrophilic substitution reaction; Step (2) Expand the aromatic blocks on both sides of the rigid backbone through the Suzuki reaction; Step (3) React intermediate B with iodine chloride to iodize the end of the benzene ring; Step (4) Expand the aromatic blocks again through the Suzuki reaction.

[0021] If precursor molecules only stack with π-π interactions to form nanotubes, their stability is not high and they are not easy to form gels. Therefore, this invention introduces hydrogen bond donors and acceptors into the precursor molecules at the same time, so that when the precursor molecules stack using π-π interactions, they are also subject to hydrogen bond anchoring and interlocking, which makes the formed gel tubular structure stable.

[0022] Preferably, in the preparation method of the above compound, the dendritic polyethylene glycol tetrabranch is synthesized according to the literature: Angewandte Chemie International Edition, 2005, 44: 5810-5814; the reaction structural formula is:

[0023]

[0024] The synthetic route is summarized as follows: Molecule d (chiral tetraethylene glycol chain) undergoes a substitution reaction with 3-chloro-2-chloromethylpropene in sodium hydride to generate molecule e. Molecule e undergoes an addition oxidation reaction with a borane tetrahydrofuran complex in sodium hydroxide / hydrogen peroxide to obtain molecule f. Molecule f then undergoes a substitution reaction with 3-chloro-2-chloromethylpropene in sodium hydride to generate molecule g. Molecule g then reacts with a borane tetrahydrofuran complex in sodium hydroxide / hydrogen peroxide to obtain dendritic polyethylene glycol tetrabranch h.

[0025] The reaction structure for the preparation of the compound is as follows:

[0026]

[0027] Preferably, in the preparation method of the above compound, the specific steps of the substitution reaction in step (1) are as follows: 2,6-dibromo,4-nitropyridine and dendritic polyethylene glycol tetra-branched chain are dissolved in organic solvent a, an alkaline catalyst is added and the mixture is reacted, purified, and intermediate A is obtained.

[0028] Preferably, in step (1), the molar ratio of 2,6-dibromo,4-nitropyridine, dendritic polyethylene glycol tetra-branched chain, and alkaline catalyst is 2,6-dibromo,4-nitropyridine: dendritic polyethylene glycol tetra-branched chain: alkaline catalyst = 1:(1-1.3):(5-6); the alkaline catalyst is sodium hydride; the conditions for the substitution reaction are: stirring in an ice-water bath for 30-45 min, and then reacting at 90-92℃ for 12-15 h.

[0029] Preferably, the weight (g) ratio of the 2,6-dibromo,4-nitropyridine to the volume (mL) ratio of the organic solvent a is 1:100.

[0030] Preferably, the organic solvent a is either tetrahydrofuran or N,N-dimethylformamide.

[0031] Preferably, in steps (2) and (4), the catalyst is tetra(triphenylphosphine)palladium.

[0032] Preferably, in step (1), the purification method of intermediate A is as follows: add deionized water and react until the solution is clear, remove the solvent by vacuum distillation, and then extract with ethyl acetate and dichloromethane in sequence. After removing residual water from the organic phase with anhydrous magnesium sulfate, concentrate it, and then perform silica gel column chromatography with ethyl acetate and methanol in a volume ratio of 50:1 as the eluent.

[0033] More preferably, in step (1), the molar ratio of 2,6-dibromo,4-nitropyridine to dendritic polyethylene glycol tetra-branched chain is 2,6-dibromo,4-nitropyridine: dendritic polyethylene glycol tetra-branched chain = 1:1.1.

[0034] Preferably, in steps (2) and (4), the catalyst is tetra(triphenylphosphine)palladium.

[0035] Preferably, the specific steps of the Suzuki coupling reaction in step (2) are as follows: intermediate A obtained in step (1) and 4-(trimethylsilane)biphenylboronic acid are dissolved in organic solvent a, an inorganic alkaline solution is added, oxygen is removed, a catalyst is added to react, and the mixture is purified to obtain intermediate B.

[0036] Preferably, the organic solvent a is either tetrahydrofuran or N,N-dimethylformamide.

[0037] The inorganic alkaline solution is either an aqueous solution of potassium carbonate or an aqueous solution of sodium carbonate.

[0038] An inorganic alkaline solution is used to activate the phenylboronic acid group and neutralize the boric acid generated in the reaction. Preferably, in step (2), the molar ratio of intermediate A, 4-(trimethylsilane)biphenylboronic acid and catalyst is intermediate A: 4-(trimethylsilane)biphenylboronic acid: catalyst = 1:(2-2.5):0.3; the conditions for the Suzuki coupling reaction are: 90-92℃ for 20-24 h.

[0039] Preferably, the volume ratio of organic solvent a to inorganic alkaline solution is 5:4.

[0040] Preferably, the weight (g) ratio of intermediate A to the volume (mL) ratio of organic solvent a is 11.2:50.

[0041] Preferably, in step (2), the purification method of intermediate B is as follows: the solvent is removed by rotary evaporation, and the organic phase is extracted sequentially with ethyl acetate and dichloromethane. The organic phase is concentrated after removing residual water with anhydrous magnesium sulfate, and silica gel column chromatography is performed with ethyl acetate and methanol in a volume ratio of 20:1 as the eluent.

[0042] More preferably, in step (2), the molar ratio of intermediate A to 4-(trimethylsilane)biphenylboronic acid is intermediate A: 4-(trimethylsilane)biphenylboronic acid = 1:2.5.

[0043] Preferably, the specific steps of the iodination reaction in step (3) are as follows: intermediate B obtained in step (2) is dissolved in organic solvent b with the iodination agent, reacted, sodium thiosulfate solution is added, stirred until the solution is transparent and yellowish, purified, and intermediate C is obtained.

[0044] Preferably, in step (3), the molar ratio of intermediate B to iodide is intermediate B: iodide = 1: (5-9); the iodide is iodine monochloride; the iodination reaction is carried out under argon protection at -78°C for 4-6 hours.

[0045] Preferably, in step (3), the molar ratio of intermediate B to sodium thiosulfate is intermediate B: sodium thiosulfate = 1:(5-7).

[0046] Preferably, the stirring time is at least 12 hours until the solution turns a transparent yellowish color, then it is moved to room temperature and stirred for another 2 hours before the reaction is stopped. Sodium thiosulfate is used to quench iodine monochloride and iodine, a byproduct generated during the reaction.

[0047] Preferably, the organic solvent b is dichloromethane.

[0048] Preferably, the weight (g) ratio of intermediate B to the volume (mL) ratio of organic solvent b is 0.22:50.

[0049] Preferably, in step (3), the purification method of intermediate C is as follows: the aqueous phase is extracted with dichloromethane, the organic phase is concentrated after removing residual water with anhydrous magnesium sulfate, and silica gel column chromatography is performed using ethyl acetate and methanol in a volume ratio of 10:1 as the eluent.

[0050] More preferably, in step (3), the molar ratio of intermediate B to iodide is intermediate B: iodide = 1:7.

[0051] Preferably, the specific reaction steps of the Suzuki coupling reaction in step (4) are as follows: the intermediate C obtained in step (3) and 4-hydroxybiphenylboronic acid are dissolved in organic solvent a, an inorganic alkaline solution is added, oxygen is removed, a catalyst is added to react, and the mixture is purified to obtain the compound.

[0052] Preferably, in step (4), the molar ratio of intermediate C to 4-hydroxybiphenylboronic acid is intermediate C: 4-hydroxybiphenylboronic acid = 1: (2-2.5); the conditions for the Suzuki coupling reaction are: 90-92℃ for 20-24h.

[0053] Preferably, in step (4), the volume ratio of organic solvent a to inorganic alkaline solution is 5:4.

[0054] Preferably, the weight (g) ratio of the intermediate C to the volume (mL) ratio of the organic solvent a is 0.39:25.

[0055] Preferably, in step (4), the purification method of the compound is as follows: the solvent is removed by rotary evaporation, the residual water is removed by anhydrous magnesium sulfate and then concentrated, and silica gel column chromatography is performed using ethyl acetate and methanol in a volume ratio of 10:1 as the eluent.

[0056] More preferably, in step (4), the molar ratio of intermediate C to 4-hydroxybiphenylboronic acid is intermediate C: 4-hydroxybiphenylboronic acid = 1: 2.4.

[0057] Thirdly, the present invention provides a hydrogel comprising an aqueous solution of the compound of claim 1, wherein the mass percentage of the compound of claim 1 in the hydrogel is 4%-6%.

[0058] The compound was prepared into a 4-6 wt% aqueous solution, and the solution was sonicated for 5 minutes using a cell disruptor to obtain the hydrogel.

[0059] Fourthly, the present invention provides the application of the above-mentioned hydrogel in the separation of miscible mixed solutions.

[0060] The present invention utilizes the porous structure of traditional hydrogels to selectively adsorb miscible mixed solutions through the interweaving of hydrophilic and hydrophobic channels, thereby achieving heterogeneous separation of homogeneous liquid mixtures. The multidimensional hybrid channels are beneficial for the separation of miscible bodies, and the multi-level nanostructure provides permeation differences for heterogeneous components.

[0061] Preferably, the separation method involves coating the hydrogel onto the diaphragm of an ultrafiltration tube, allowing it to form a film, adding a miscible mixed solution, and centrifuging; the miscible mixed solution is a mixture of phenylethanol (AP) and acetophenone (PE).

[0062] Preferably, the water in the aqueous solution evaporates to form a dry gel film, and the placement time is 5 hours.

[0063] Preferably, the concentration of the AP / PE mixed aqueous solution is 200 mg / L, and the volume of the aqueous solution separated each time is 100 μL.

[0064] The hydrogel prepared in this invention achieves a permeability of 15.0 × 10⁻⁶ for phenylethyl alcohol (PE) and acetophenone (AP). -5 mgcm -2 min -1 5.4×10 -5 mg cm -2 min -1 This enables efficient separation of AP / PE co-solutions in equiproportional mixed solutions, solving the problem of difficult separation in homogeneous co-solutions.

[0065] Compared with the prior art, the present invention has the following beneficial effects:

[0066] 1. The present invention relates to the assembly of topologically rigid-flexible amphiphilic molecules. By utilizing the synergistic interaction of π-π interactions and hydrogen bonds, the assembly of amphiphilic molecules is developed to construct a superhydrophobic tubular one-dimensional gel precursor, thereby stabilizing the properties of the prepared hydrogel.

[0067] 2. The hydrogel of the present invention contains both hydrophilic and hydrophobic channels: hydrophilic channels composed of flexible dendritic polyethylene glycol chains on the periphery, and superhydrophobic nonpolar cavities assembled by π-π stacking of rigid benzene rings; the simultaneous presence of hydrophilic and hydrophobic channels in the hydrogel avoids phase separation, which is more conducive to the rapid penetration of effective substances and the selective separation of nonpolar organic substances in water.

[0068] 3. The hydrophilic-hydrophobic hybrid hydrogel of the present invention has a high efficiency in AP / PE separation and can be further applied to other separation, adsorption and other fields. It has broad application prospects in chemical separation and pollutant removal. Attached Figure Description

[0069] Figure 1 The nuclear magnetic resonance hydrogen and carbon spectra of the compound in Example 1 are shown.

[0070] Figure 2 Electrospray ionization mass spectra of the compound in Example 1.

[0071] Figure 3 This is a schematic diagram of the hydrogel formation in Application Example 1.

[0072] Figure 4 The image shows the morphology of the hydrogel before and after formation in Example 1.

[0073] Figure 5 TEM images, AFM images, and XRD patterns of the hydrogel used in Example 1 are shown.

[0074] Figure 6 The figure shows the separation results of AP / PE using the hydrogel in Example 1. Detailed Implementation

[0075] To better illustrate the purpose, technical solution, and advantages of this invention, the invention will be further described below with reference to specific embodiments. Unless otherwise specified, the experimental methods used in the embodiments and comparative examples of this invention are conventional methods, and the materials and reagents used are commercially available unless otherwise specified.

[0076] Example 1:

[0077] An embodiment of the compound of the present invention; the structural formula of the compound is shown in the following formula (Ⅰ):

[0078]

[0079] The structural formula of R is shown in equation (Ⅱ):

[0080]

[0081] The preparation method of the above-mentioned compound includes the following steps:

[0082] 1. Synthesis of tetrabranched dendritic polyethylene glycol (Reference: Angewandte Chemie International Edition, 2005, 44: 5810-5814):

[0083]

[0084] The synthetic route is summarized as follows: Molecule d (chiral tetraethylene glycol chain) undergoes a substitution reaction with 3-chloro-2-chloromethylpropene in sodium hydride to generate molecule e. Molecule e undergoes an addition oxidation reaction with a borane tetrahydrofuran complex in sodium hydroxide / hydrogen peroxide to obtain molecule f. Molecule f then undergoes a substitution reaction with 3-chloro-2-chloromethylpropene in sodium hydride to generate molecule g. Molecule g then reacts with a borane tetrahydrofuran complex in sodium hydroxide / hydrogen peroxide to obtain dendritic polyethylene glycol tetrabranch h.

[0085] 2. Preparation of the compound:

[0086] (1) Dissolve 2,6-dibromo,4-nitropyridine (0.30 g, 1.05 mmol) in 30 mL of tetrahydrofuran. Add sodium hydride (1.15 g, 5.25 mmol) slowly while stirring in an ice bath. After stirring for 0.5 h, add dendritic polyethylene glycol tetra-branched chain (1.5 g, 1.315 mmol). Then remove the ice bath and heat to 90 °C. React for 12 h. After stopping the reaction, slowly add deionized water until the solution becomes clear. Remove tetrahydrofuran by rotary evaporation. Extract the aqueous phase with ethyl acetate and dichloromethane to obtain the organic phase. Remove residual water with anhydrous magnesium sulfate. After rotary evaporation and concentration, purify by silica gel column chromatography. The eluent used for purification is ethyl acetate and methanol in a volume ratio of 50:1 to obtain intermediate A (0.56 g, 40%).

[0087] (2) Intermediate A (0.56 g, 0.42 mmol) and 4-(trimethylsilane)biphenylboronic acid (0.251 g, 0.93 mmol) were dissolved in 25 mL of tetrahydrofuran solution. 20 mL of 2 mol / L potassium carbonate aqueous solution was added to remove oxygen. Then, the catalyst tetra(triphenylphosphine)palladium (0.15 g, 0.125 mmol) was quickly added and the temperature was raised to 90 °C for 20 h. After the reaction was stopped, tetrahydrofuran was removed by rotary evaporation. The aqueous phase was extracted with ethyl acetate and dichloromethane, respectively. The organic phase was purified by removing residual water with anhydrous magnesium sulfate, concentrated by rotary evaporation, and purified by silica gel column chromatography. The eluent used for purification was ethyl acetate and methanol in a volume ratio of 20:1 to obtain intermediate B (0.44 g, 64%).

[0088] (3) Dissolve intermediate B (0.44 g, 0.27 mmol) in anhydrous dichloromethane (100 mL), cool to -78 °C, and slowly add a dichloromethane solution of iodine monochloride (1.0 mol / L, 1.89 mL, 1.89 mmol). React for 4 h, then add 1 mol / L sodium thiosulfate solution to quench the reaction until the solution turns into a transparent yellowish color. Stop the reaction after stirring at room temperature for 2 h. After separating the organic phase, extract the aqueous phase with dichloromethane. Remove residual water from the obtained organic phase with anhydrous magnesium sulfate, concentrate by rotary evaporation, and purify by silica gel column chromatography. The eluent used for purification is ethyl acetate and methanol in a volume ratio of 10:1 to obtain intermediate C (0.39 g, 83%).

[0089] (4) Intermediate C (0.39 g, 0.23 mmol) and 4-hydroxybiphenylboronic acid (1.18 g, 0.55 mmol) were dissolved in 25 mL of tetrahydrofuran. 20 mL of 2 mol / L potassium carbonate aqueous solution was added. After deoxygenation, tetra(triphenylphosphine)palladium (0.11 g, 0.089 mmol) was added, and the mixture was heated to 90 °C and reacted for 20 h. After the reaction was stopped, tetrahydrofuran was removed by rotary evaporation. The aqueous phase was extracted with ethyl acetate and dichloromethane to obtain the organic phase. Residual water was removed by anhydrous magnesium sulfate. After rotary evaporation and concentration, the product was purified by silica gel column chromatography using ethyl acetate and methanol in a volume ratio of 10:1 to obtain a relatively pure product (0.23 g, 56%). The product was further purified by high performance liquid chromatography using a C8M column (Nucifera, 250 mm × 30 mm) with acetonitrile as the mobile phase to obtain the compound.

[0090] The structure of intermediate A is shown in formula (III); the structure of intermediate B is shown in formula (IV); the structure of intermediate C is shown in formula (V):

[0091]

[0092]

[0093] Example 2:

[0094] An embodiment of the compound of the present invention; the structural formula of the compound is shown in the following formula (Ⅰ):

[0095]

[0096] The structural formula of R is shown in equation (Ⅱ):

[0097]

[0098] The preparation method of the above-mentioned compound includes the following steps:

[0099] 1. The synthesis of the dendritic polyethylene glycol tetrabranch is the same as in Example 1.

[0100] 2. Preparation of the compound:

[0101] (1) Dissolve 2,6-dibromo,4-nitropyridine (0.30 g, 1.05 mmol) in 30 mL of tetrahydrofuran. Add sodium hydride (5.25 mmol) slowly while stirring in an ice bath. After stirring for 0.5 h, add dendritic polyethylene glycol tetra-branched (1.20 g, 1.05 mmol). Then remove the ice bath and heat to 90 °C. React for 12 h. After stopping the reaction, slowly add deionized water until the solution becomes clear. Remove tetrahydrofuran by rotary evaporation. Extract the aqueous phase with ethyl acetate and dichloromethane to obtain the organic phase. Remove residual water with anhydrous magnesium sulfate. After rotary evaporation and concentration, purify by silica gel column chromatography. The eluent used for purification is ethyl acetate and methanol in a volume ratio of 50:1 to obtain intermediate A (0.50 g, 36%).

[0102] (2) Intermediate A (0.56 g, 0.42 mmol) and 4-(trimethylsilane)biphenylboronic acid (0.23 g, 0.84 mmol) were dissolved in 25 mL of tetrahydrofuran solution. 20 mL of 2 mol / L potassium carbonate aqueous solution was added to remove oxygen. Then, the catalyst tetra(triphenylphosphine)palladium (0.15 g, 0.125 mmol) was quickly added and the temperature was raised to 90 °C for 20 h. After the reaction was stopped, tetrahydrofuran was removed by rotary evaporation. The aqueous phase was extracted with ethyl acetate and dichloromethane, respectively. The organic phase was purified by removing residual water with anhydrous magnesium sulfate, concentrated by rotary evaporation, and purified by silica gel column chromatography. The eluent used for purification was ethyl acetate and methanol in a volume ratio of 20:1 to obtain intermediate B (0.41 g, 59%).

[0103] (3) Intermediate B (0.44 g, 0.27 mmol) was dissolved in anhydrous dichloromethane (100 mL), cooled to -78 °C, and a dichloromethane solution of iodine monochloride (1.0 mol / L, 1.89 mL, 1.35 mmol) was slowly added dropwise. The reaction was allowed to proceed for 4 h, and then quenched with 1 mol / L sodium thiosulfate solution until the solution turned into a transparent yellowish color. The reaction was stopped after stirring at room temperature for 2 h. After separating the organic phase, the aqueous phase was extracted with dichloromethane. The organic phase was then purified by removing residual water with anhydrous magnesium sulfate, concentrated by rotary evaporation, and purified by silica gel column chromatography. The eluent used for purification was ethyl acetate and methanol in a volume ratio of 10:1 to obtain intermediate C (0.38 g, 82%).

[0104] (4) Intermediate C (0.39 g, 0.23 mmol) and 4-hydroxybiphenylboronic acid (0.99 g, 0.46 mmol) were dissolved in 25 mL of tetrahydrofuran. 20 mL of 2 mol / L potassium carbonate aqueous solution was added. After deoxygenation, tetra(triphenylphosphine)palladium (0.11 g, 0.089 mmol) was added, and the mixture was heated to 90 °C and reacted for 20 h. After the reaction was stopped, tetrahydrofuran was removed by rotary evaporation. The aqueous phase was extracted with ethyl acetate and dichloromethane to obtain the organic phase. Residual water was removed by anhydrous magnesium sulfate. After rotary evaporation and concentration, the product was purified by silica gel column chromatography using ethyl acetate and methanol in a volume ratio of 10:1 to obtain a relatively pure product (0.22 g, 54%). The product was further purified by high performance liquid chromatography using a C8M column (Nucifera, 250 mm × 30 mm) with acetonitrile as the mobile phase to obtain the compound.

[0105] The structure of intermediate A is shown in formula (III); the structure of intermediate B is shown in formula (IV); the structure of intermediate C is shown in formula (V):

[0106]

[0107]

[0108] Example 3:

[0109] An embodiment of the compound of the present invention; the structural formula of the compound is shown in the following formula (Ⅰ):

[0110]

[0111] The structural formula of R is shown in equation (Ⅱ):

[0112]

[0113] The preparation method of the above-mentioned compound includes the following steps:

[0114] 1. The synthesis of the dendritic polyethylene glycol tetrabranch is the same as in Example 1.

[0115] 2. Preparation of the compound:

[0116] (1) Dissolve 2,6-dibromo,4-nitropyridine (0.30 g, 1.05 mmol) in 30 mL of tetrahydrofuran. Add sodium hydride (1.38 g, 6.3 mmol) slowly while stirring in an ice bath. After stirring for 0.5 h, add dendritic polyethylene glycol tetra-branched (1.56 g, 1.365 mmol). Then remove the ice bath and heat to 90 °C. React for 12 h. After stopping the reaction, slowly add deionized water until the solution becomes clear. Remove tetrahydrofuran by rotary evaporation. Extract the aqueous phase with ethyl acetate and dichloromethane to obtain the organic phase. Remove residual water with anhydrous magnesium sulfate. After rotary evaporation and concentration, purify by silica gel column chromatography. The eluent used for purification is ethyl acetate and methanol in a volume ratio of 50:1 to obtain intermediate A (0.57 g, 41%).

[0117] (2) Intermediate A (0.56 g, 0.42 mmol) and 4-(trimethylsilane)biphenylboronic acid (0.28 g, 1.05 mmol) were dissolved in 25 mL of tetrahydrofuran solution. 20 mL of 2 mol / L potassium carbonate aqueous solution was added to remove oxygen. Then, the catalyst tetra(triphenylphosphine)palladium (0.15 g, 0.125 mmol) was quickly added and the temperature was raised to 90 °C for 20 h. After the reaction was stopped, tetrahydrofuran was removed by rotary evaporation. The aqueous phase was extracted with ethyl acetate and dichloromethane, respectively. The organic phase was purified by removing residual water with anhydrous magnesium sulfate, concentrated by rotary evaporation, and purified by silica gel column chromatography. The eluent used for purification was ethyl acetate and methanol in a volume ratio of 20:1 to obtain intermediate B (0.45 g, 66%).

[0118] (3) Intermediate B (0.44 g, 0.27 mmol) was dissolved in anhydrous dichloromethane (100 mL), cooled to -78 °C, and a dichloromethane solution of iodine monochloride (1.0 mol / L, 2.43 mL, 2.43 mmol) was slowly added dropwise. The reaction was allowed to proceed for 4 h, and then quenched with 1 mol / L sodium thiosulfate solution until the solution turned into a transparent yellowish color. The reaction was stopped after stirring at room temperature for 2 h. After separating the organic phase, the aqueous phase was extracted with dichloromethane. The organic phase was then purified by removing residual water with anhydrous magnesium sulfate, concentrated by rotary evaporation, and purified by silica gel column chromatography. The eluent used for purification was ethyl acetate and methanol in a volume ratio of 10:1 to obtain intermediate C (0.40 g, 84%).

[0119] (4) Intermediate C (0.39 g, 0.23 mmol) and 4-hydroxybiphenylboronic acid (1.23 g, 0.575 mmol) were dissolved in 25 mL of tetrahydrofuran. 20 mL of 2 mol / L potassium carbonate aqueous solution was added. After deoxygenation, tetra(triphenylphosphine)palladium (0.11 g, 0.089 mmol) was added, and the mixture was heated to 90 °C and reacted for 20 h. After the reaction was stopped, tetrahydrofuran was removed by rotary evaporation. The aqueous phase was extracted with ethyl acetate and dichloromethane to obtain the organic phase. The residual water was removed with anhydrous magnesium sulfate. After rotary evaporation and concentration, the product was purified by silica gel column chromatography using ethyl acetate and methanol in a volume ratio of 10:1 to obtain a relatively pure product (0.24 g, 58%). The product was further purified by high performance liquid chromatography using a C8M column (Nucifera, 250 mm × 30 mm) with acetonitrile as the mobile phase to obtain the compound.

[0120] The structure of intermediate A is shown in formula (III); the structure of intermediate B is shown in formula (IV); the structure of intermediate C is shown in formula (V):

[0121]

[0122]

[0123] Application Example 1:

[0124] An example of the application of the compound described in this invention; this example is a hydrogel comprising an aqueous solution of the compound prepared in Example 1; wherein the mass percentage of the compound prepared in Example 1 in the hydrogel is 4%.

[0125] The preparation method of the above-mentioned hydrogel includes the following steps:

[0126] The compound prepared in Example 1 (16 mg, 8.80 μmol) was weighed and dispersed in 400 μL of ultrapure water. The hydrogel of the present invention was obtained by sonication for 30 min using a cell disruptor.

[0127] Application Example 2:

[0128] An example of the application of the compound described in this invention; this example is a hydrogel comprising an aqueous solution of the compound prepared in Example 1; wherein the mass percentage of the compound prepared in Example 1 in the hydrogel is 6%.

[0129] The preparation method of the above-mentioned hydrogel includes the following steps:

[0130] The compound prepared in Example 1 (24 mg, 13.20 μmol) was weighed and dispersed in 400 μL of ultrapure water. The hydrogel of the present invention was obtained by sonication for 30 min using a cell disruptor.

[0131] Test Example 1

[0132] Compound testing:

[0133] The structures of the compounds obtained in Examples 1-3 were analyzed by nuclear magnetic resonance (NMR). 1 HNMR and electrospray ionization mass spectrometry were used to test the results as follows: Figure 1 and Figure 2 As shown, the specific data is as follows:

[0134] 1 H NMR(400MHz,Chloroform-d)δ8.23(d,J=8.0Hz,4H),7.70(m,18H),7.58(d,J=8.0Hz,4H),7.47(d,J=8.0H z,4H),6.92(d,J=8.0Hz,4H),4.22(s,2H),3.68–3.37(m,88H),2.54–2.41(m,2H),1.12(d,J=6.1Hz,12H).

[0135] 13 C-NMR (600MHz, Chloroform-d) δ169.6,167.4,156.2,141.2,140.2,132.1,128.1,127.7,127.4,127. 3,127.2,127.1,126.9,115.8,77.2,77.0,76.8,75.6,74.9,71.9,70.7,70.6,70.5,58.9,40.8,17.1;

[0136] ESI-MS: m / z calculated for C 105 H 141 NO 25 [M+H] + ,1917.98; found: [M+H] + ,1917.

[0137] The test results are consistent with the molecular structure, proving that the compounds prepared in Examples 1-3 have a V-shaped structure and are the target molecules.

[0138] Test Example 2

[0139] Hydrogel test:

[0140] The formation process of hydrogels is as follows: Figure 3As shown. The hydrogels prepared using Examples 1-2 were subjected to morphological observation and XRD analysis using transmission electron microscopy (TEM), atomic force microscopy (AFM), and XRD patterns, respectively. The results are shown below. Figure 4 , 5 As shown.

[0141] A schematic diagram of the formation of gel water is shown below. Figure 3 As shown: The compound prepared in the application example is a V-type molecule composed of two blocks, including a V-type aromatic carbon block and an outer hydrophilic flexible block.

[0142] At low concentrations, the gel precursor (i.e., V-shaped molecules) self-assembles into helical tubes in aqueous solution, as shown in the figure. As the concentration slowly increases to a certain gel concentration (4-6 wt%), the concentration of helical nanotubes increases and they further aggregate. At this gel concentration, these tube-tube aggregates form a hydrogel.

[0143] Helical tubules aggregate to form a gel. The pores inside the helical tubules are hydrophobic, while the middle of the aggregated tubules is composed of hydrophilic polyethylene glycol branches. The solvent water is dispersed outside these pores, so the tubes are equivalent to a hydrophilic channel. Thus, the gel as a whole has a staggered arrangement of tubular pores with hydrophobic interiors and hydrophilic channels on the outside.

[0144] Figure 4 This indicates that the hydrogel is a flowable solution before sonication using a cell disruptor, and forms a gel after sonication, which can solidify above the bottle without falling off; the hydrogel prepared by this invention is yellowish-white in color.

[0145] from Figure 5 As can be seen, the XRD results confirm that the hydrophilic-hydrophobic porous hybrid hydrogel has a face-centered cubic pore structure and verify its assembly structure. The XRD results show that the internal microstructure of the helical tubules has 10 layers, as shown in the figure. V-shaped molecules are stacked in a helical shape and extend in one dimension to form helical tubules as seen in the TEM image. Furthermore, the AFM image confirms the gel formation process, with the helical tubules aggregating with each other, and the thicker white part is the aggregated gel.

[0146] Test Example 3

[0147] Performance Testing – Separation Performance Testing:

[0148] 1. Single-component permeation test: To illustrate the difference in sieving performance of the hydrogel prepared in Example 1 for AP and PE, a single-component organic aqueous solution was used for sieving test.

[0149] Add 400 μL of the hydrogel prepared in Application Example 1 to an ultrafiltration tube. Place the ultrafiltration tube flat with its surface facing upwards and use a pipette to evenly spread the gel on the septum of the ultrafiltration tube. Let it stand for 5 hours until the gel forms a film and adheres to the septum. Then, add 400 μL of aqueous solutions of AP and PE to the ultrafiltration tube, respectively. After capping the ultrafiltration tube, centrifuge it for 10 min. After centrifugation, take 20 μL of the filtrate separated from the bottom of the ultrafiltration tube and use a microsyringe to analyze it by high performance liquid chromatography.

[0150] The method for preparing the AP and PE aqueous solutions is as follows: Take 20 mg of AP and 20 mg of PE and add them to 50 mL of water respectively. After dissolving, a mixed aqueous solution with an AP and PE concentration of 200 mg / L can be obtained.

[0151] 2. Two-component osmosis experiment

[0152] Add 400 μL of the hydrogel prepared in Application Example 1 to an ultrafiltration tube. Place the ultrafiltration tube flat with its surface facing upwards and use a pipette to evenly spread the gel on the septum of the ultrafiltration tube. Let it stand for 5 hours until the gel forms a film and adheres to the septum. Then add 400 μL of a 1:1 mixture of phenylethanol (AP) and acetophenone (PE) to the ultrafiltration tube. After capping the ultrafiltration tube, centrifuge it for 10 min. After centrifugation, take 20 μL of the filtrate separated from the bottom of the ultrafiltration tube and use a microsyringe to analyze it by high performance liquid chromatography.

[0153] The preparation method of the AP / PE mixed solution is as follows: take AP (20mg) and PE (20mg) and add them to 50mL of water respectively, and then take 5mL of AP and PE solution respectively and mix them to obtain a mixed aqueous solution with AP and PE concentrations of 200mg / L.

[0154] The separation conditions for the high-performance liquid chromatography (HPLC) were as follows: C8 column (Nucifera, 250 mm × 4.6 mm); mobile phase: acetonitrile / methanol = 8 / 2 (v / v, HPLC grade); flow rate: 1 mL / min. The conversion rate of the obtained reaction system was... Figure 6 Presented in the middle.

[0155] from Figure 6 It can be seen that the hydrogel prepared in Example 1 has a good separation effect on AP and PE. When only a single-component AP and PE solution is used for sieving, the permeability of the hydrogel membrane to PE and AP is 15.0 × 10⁻⁶. -5 mg cm -2 min -1 With 5.4×10 -5 mg cm- 2 min -1When using a mixture of AP / PE for sieving, the differences in permeability between the single components were further amplified, with the permeability of PE and AP reaching 21.2 × 10⁻⁶. -5 mg cm -2 min -1 and 3.8×10 -5 mg cm -2 min -1 This indicates that the hydrophilic-hydrophobic porous hybrid hydrogel has a significant sieving effect on AP and PE, thereby achieving the purpose of separating AP and PE.

[0156] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A compound, characterized in that, The structural formula of the compound is shown in the following formula (Ⅰ): The structural formula of R is shown in equation (Ⅱ):

2. A method for preparing the compound as described in claim 1, characterized in that, Includes the following steps: (1) 2,6-Dibromo,4-nitropyridine reacts with dendritic polyethylene glycol tetra-branched chains in the presence of an alkaline catalyst to generate intermediate A through a substitution reaction; The structural formula of the dendritic polyethylene glycol tetra-branched chain is shown in formula (A): (2) Intermediate A obtained in step (1) is reacted with 4-(trimethylsilane)biphenylboronic acid via a Suzuki coupling reaction under the action of a catalyst to generate intermediate B; (3) After reacting intermediate B obtained in step (2) with an iodizing agent, sodium thiosulfate is added and stirred to obtain intermediate C; (4) The intermediate C obtained in step (3) is reacted with 4-hydroxybiphenylboronic acid via a Suzuki coupling reaction under the action of a catalyst to generate the compound; The structure of intermediate A is shown in formula (III); the structure of intermediate B is shown in formula (IV); the structure of intermediate C is shown in formula (V):

3. The method for preparing the compound according to claim 2, characterized in that, In steps (2) and (4), the catalyst is tetra(triphenylphosphine)palladium.

4. The method for preparing the compound according to claim 2, characterized in that, In step (1), the molar ratio of 2,6-dibromo,4-nitropyridine, dendritic polyethylene glycol tetra-branched chain, and alkaline catalyst is 2,6-dibromo,4-nitropyridine: dendritic polyethylene glycol tetra-branched chain: alkaline catalyst = 1:(1-1.3):(5-6); the alkaline catalyst is sodium hydride; the conditions for the substitution reaction are: first, stirring in an ice-water bath for 30-45 min, and then reacting at 90-92℃ for 12-15 h.

5. The method for preparing the compound according to claim 2, characterized in that, In step (2), the molar ratio of intermediate A, 4-(trimethylsilane)biphenylboronic acid and catalyst is intermediate A: 4-(trimethylsilane)biphenylboronic acid: catalyst = 1:(2-2.5):0.3; the conditions for the Suzuki coupling reaction are: 90-92℃ for 20-24h.

6. The method for preparing the compound according to claim 2, characterized in that, In step (3), the molar ratio of intermediate B to iodizing agent is intermediate B: iodizing agent = 1: (5-9); the iodizing agent is iodine monochloride; the conditions for the iodination reaction are: reaction at -78℃ for 4-6 hours under argon protection.

7. The method for preparing the compound according to claim 2, characterized in that, In step (4), the molar ratio of intermediate C to 4-hydroxybiphenylboronic acid is intermediate C: 4-hydroxybiphenylboronic acid = 1: (2-2.5); the conditions for the Suzuki coupling reaction are: 90-92℃ for 20-24h.

8. A hydrogel, characterized in that, The hydrogel comprises an aqueous solution of the compound of claim 1; wherein the mass percentage of the compound of claim 1 in the hydrogel is 4%-6%.

9. The application of the hydrogel as described in claim 8 in the separation of miscible mixed solutions.

10. The application as described in claim 9, characterized in that, The separation method is as follows: the hydrogel is coated onto the diaphragm of the ultrafiltration tube, and after the membrane is formed, a miscible mixed solution is added and centrifuged; the miscible mixed solution is a mixture of phenylethanol and acetophenone.

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