Supramolecular hydrogel with aggregation-induced emission characteristic, preparation method of supramolecular hydrogel and application of supramolecular hydrogel in photocatalysis

Abstract

The invention belongs to the technical field of photocatalysis, and particularly discloses supramolecular hydrogel with the aggregation-induced emission characteristic, a preparation method of the supramolecular hydrogel and application of the supramolecular hydrogel to photocatalysis, the structural formula of amphiphilic guest molecules is as shown in the formula (1): # imgabs0 #, n is 2-10, and the number m of carbon atoms of alkyl chains is 6-18. The supramolecular hydrogel with the aggregation-induced emission characteristic is prepared from a host-guest compound formed by the amphiphilic guest molecule and water-soluble pillararene as well as a photoinitiator and an acceptor molecule of the host-guest compound. And catalyzing a dehalogenation reaction and / or an oxidative coupling reaction of benzylamine.

Description

Technical Field

[0001] The present invention relates to the field of photocatalysis technology; in particular, it relates to a supramolecular hydrogel with aggregation-induced emission characteristics, a preparation method thereof, and an application in photocatalysis. Background Technique

[0002] Hydrogels are a type of polymer material with a three-dimensional network structure. Traditional hydrogel preparation methods usually involve complex chemical cross-linking processes or physical methods, which have problems such as harsh preparation conditions, high time costs, and difficulties in regulating the gel structure and properties. Supramolecular hydrogels are a type of polymer material with a three-dimensional network structure formed through non-covalent interactions (such as hydrogen bonds, hydrophobic interactions, van der Waals forces, etc.). Compared with traditional hydrogels, supramolecular hydrogels have unique dynamic reversibility and responsiveness, and can undergo reversible sol-gel transitions under external stimuli (such as temperature, pH, light, etc.), showing good biocompatibility, biodegradability, and physicochemical stability. These characteristics enable supramolecular hydrogels to have broad application prospects in the fields of biomedicine, tissue engineering, drug delivery, sensing detection, and photocatalysis.

[0003] Aggregation-induced emission (AIE) refers to a photophysical phenomenon in which molecular aggregates exhibit stronger emission than individual molecules. The emergence of AIE materials has greatly promoted the development of supramolecular luminescent materials because the strong luminescence phenomenon shown in the aggregated state solves the long-standing obstacle brought by the aggregation fluorescence quenching effect, thus bringing broad application prospects to AIE-based supramolecular materials in the fields of luminescent materials, sensors, bioimaging, drug delivery, and therapy.

[0004] The fluorescence resonance energy transfer (FRET) process involves non-radiative energy transfer between two fluorescent molecules, namely the energy donor and the acceptor. When there is a significant overlap between the emission spectrum of the donor molecule and the absorption spectrum of the acceptor molecule, and the distance between the two is within a certain range, energy transfer occurs. FRET technology has important application values in the research of biomolecular interactions, the detection of intracellular signal transduction, and the design of fluorescence sensors.

[0005] Traditional photocatalytic systems often can only carry out a single type of reaction, lacking versatility and high efficiency. In addition, many photocatalysts are prone to deactivation during the reaction or require complex preparation conditions, which limits their practical applications. The hydrogel photocatalytic system combines the high specific surface area, good stability of the hydrogel, and the efficient light energy conversion ability of the photocatalyst, showing unique advantages. In the hydrogel photocatalytic system, the hydrogel can adsorb and enrich reactants through its three-dimensional network structure, thereby improving the photocatalytic efficiency. In addition, the designability and modifiability of the hydrogel enable the further optimization of photocatalytic performance and the expansion of its application scope in environmental governance, organic synthesis, energy conversion and other fields by introducing different functional groups or encapsulating different molecules. Summary of the Invention

[0006] Aiming at the defects in the prior art, the purpose of the present invention is to provide a photocatalytic system based on supramolecular hydrogels. This system combines supramolecular chemistry, fluorescence resonance energy transfer (FRET) mechanism and photocatalytic technology to form a brand-new photocatalytic system, providing new ideas and methods for the development of supramolecular photocatalytic technology.

[0007] The purpose of the present invention is achieved through the following solutions:

[0008] <First aspect>

[0009] An amphiphilic guest molecule, the structural formula of the amphiphilic guest molecule is as shown in formula (1):

[0010]

[0011] Among them, n is 2-10, and the number of carbon atoms m of the alkyl chain is 6-18.

[0012] As an embodiment of the present invention, the structural formula of the amphiphilic guest molecule is as shown in formula A:

[0013]

[0014] <Second aspect>

[0015] A preparation method of an amphiphilic guest molecule, comprising the following steps:

[0016] (1) React tetraethylene glycol with acryloyl halide in the presence of an acid-binding agent in a first organic solvent to obtain intermediate A-1;

[0017] (2) React dimethyl 5-hydroxyisophthalate with propargyl halide in a second organic solvent under alkaline conditions to obtain intermediate A-2;

[0018] (3) Hydrolyze intermediate A-2 in methanol under alkaline conditions to obtain intermediate A-3;

[0019] (4) Perform an acyl halide reaction on intermediate A-3 with an acyl halide reagent in a mixed solvent of tetrahydrofuran and N,N-dimethylformamide to obtain intermediate A-4;

[0020] (5) Carry out a condensation reaction between intermediate A-1 and intermediate A-4 in dichloromethane in the presence of an acid-binding agent to obtain intermediate A-5;

[0021] (6) Perform a click chemical reaction on intermediate A-5 with an azide compound in a mixed solvent of dichloromethane and methanol in the presence of a copper catalyst and a ligand to obtain the amphiphilic guest molecule, denoted as amphiphilic guest molecule A.

[0022] In step (1), the molar ratio of tetraethylene glycol to acryloyl halide is 1:0.4 - 0.5.

[0023] In step (2), the molar ratio of dimethyl 5-hydroxyisophthalate to propargyl halide is 1:1.0 - 1.5.

[0024] In step (3), the molar ratio of intermediate A-2 to the base is 1:4.0.

[0025] In step (4), the molar ratio of intermediate A-3 to the acyl halide reagent is 1:2.0 - 2.5.

[0026] In step (5), the molar ratio of compound A-4 to compound A-1 is 1:2.0 - 2.5.

[0027] In step (6), the molar ratio of intermediate A-5 to the azide compound is 1:1.0 - 1.5.

[0028] In step (1), the acryloyl halide is acryloyl chloride, the acid-binding agent is triethylamine, and the first organic solvent is dichloromethane.

[0029] In step (2), the propargyl halide is propargyl tribromide, the base is anhydrous potassium carbonate, and the second organic solvent is acetonitrile.

[0030] In step (3), the base is potassium hydroxide.

[0031] In step (4), the acyl halide reagent is oxalyl chloride.

[0032] In step (5), the acid-binding agent is triethylamine.

[0033] In step (6), the azide compound is sodium azide, the copper catalyst is copper(II) tetraethylammonium hexafluorophosphate, and the ligand is tris-(benzyltriazolylmethyl)amine.

[0034] Steps (1), (4), (5) and (6) are carried out under the protection of an inert gas, and the inert gas is nitrogen or argon.

[0035] In step (1), the esterification reaction is carried out at 0 °C - 30 °C to room temperature, and the reaction time is 4 - 6 hours.

[0036] In step (2), the etherification reaction is carried out under reflux conditions at 80 °C - 85 °C, and the reaction time is 12 - 14 hours.

[0037] In step (3), the hydrolysis reaction is carried out under reflux conditions at 60 °C - 75 °C, and the reaction time is 12 - 14 hours.

[0038] In step (4), the acyl halide reaction is carried out at -15 °C - 30 °C, and the reaction time is 3 - 5 hours.

[0039] In step (6), the click chemical reaction is carried out at room temperature, and the reaction time is 24 - 28 hours.

[0040] As an embodiment of the present invention, the preparation method of the amphiphilic guest molecule includes the following steps:

[0041] S1a. Under the protection of an inert gas, dissolve tetraethylene glycol and triethylamine in anhydrous dichloromethane. After cooling the reaction solution to -15 °C - 0 °C, slowly drop acryloyl chloride dissolved in anhydrous dichloromethane into the reaction solution, and then turn to stirring at room temperature for 4 h - 6 h. Obtain crude product A-1;

[0042] S1b. Add dimethyl 5-hydroxyisophthalate and anhydrous potassium carbonate into anhydrous acetonitrile. After refluxing at 80 °C - 85 °C for 30 - 45 minutes, add propargyl bromide, and reflux for 12 h - 16 h to obtain crude product A-2;

[0043] S1c. Add potassium hydroxide and compound A-2 into a methanol solvent, and reflux the reaction solution at 60 °C - 75 °C for 12 h - 14 h to obtain crude product A-3;

[0044] S1d. Under the protection of an inert gas, dissolve crude product A-3 in tetrahydrofuran and N,N-dimethylformamide, add oxalyl chloride at -15 °C - 0 °C, and stir at 25 °C - 30 °C for 3 h - 5 h to obtain crude product A-4;

[0045] S1e. Under the protection of an inert gas, add crude product A-1 and triethylamine into dichloromethane, add the dichloromethane solution of A-4 at -15 °C - 0 °C, and stir at room temperature for 12 h - 14 h to obtain crude product A-5;

[0046] S1f. Under the protection of inert gas, sodium azidosulfonate, tris-(benzyltriazolylmethyl)amine, and copper tetraethylacetonitrile hexafluorophosphate are added to methanol, and a dichloromethane solution of the crude product A-5 is added. Stir at room temperature for 24 h - 28 h to obtain the crude product A.

[0047] Preferably, in the above step S1a, the molar ratio of tetraethylene glycol to acryloyl chloride is 1:0.4 - 0.5;

[0048] In the above step S1b, the molar ratio of dimethyl 5-hydroxyisophthalate to propargyl bromide is 1:1.0 - 1.5;

[0049] In the above step S1c, the molar ratio of compound A-2 to potassium hydroxide is 1:4.0;

[0050] In the above step S1d, the molar ratio of compound A-3 to oxalyl chloride is 1:2.0 - 2.5;

[0051] In the above step S1e, the molar ratio of compound A-4 to compound A-1 is 1:2.5;

[0052] In the above step S1f, the molar ratio of compound A-5 to sodium azidosulfonate is 1:1.0 - 1.5.

[0053] The structural formula of the sodium azidosulfonate is as follows:

[0054]

[0055] The synthetic route of the amphiphilic guest molecule A is as follows:

[0056]

[0057] <Second aspect>

[0058] A preparation method of an aggregation-induced emission (AIE) supramolecular hydrogel, comprising the following steps:

[0059] Step 1. Prepare an aqueous solution of the host-guest complex, a photoinitiator solution, and a receptor molecule solution respectively; the host-guest complex is prepared from a water-soluble pillararene and the amphiphilic guest molecule described in claim 1 or 2;

[0060] Step 2. Mix the aqueous solution of the host-guest complex, the photoinitiator solution, the receptor molecule solution, and water according to a volume ratio of (1.5 - 2.5):(0.5 - 1.5):(0.5 - 1.5):(0.5 - 1.5) to obtain a mixed solution;

[0061] Step 3. Add a gelatin derivative to the mixed solution, dissolve it, inject it into a mold, and crosslink it under light (such as ultraviolet light) to form the aggregation-induced emission (AIE) supramolecular hydrogel.

[0062] In Step 1: The host-guest complex aqueous solution is prepared by a method including the following steps:

[0063] A. Dissolve the amphiphilic guest molecule as described above in water to form an amphiphilic guest molecule A solution with a concentration of 0.01 - 0.1 mM; dissolve the water-soluble pillararene (m-TPEWP5) in water to form a water-soluble pillararene B solution with a concentration of 0.01 - 0.1 mM;

[0064] B. Mix the amphiphilic guest molecule A solution and the water-soluble pillararene B solution to form a host-guest complex aqueous solution.

[0065] In Step B, the molar ratio of the amphiphilic guest molecule to the water-soluble pillararene is 1:0.8 - 1.2.

[0066] In Step B, the mixing temperature is room temperature (15 - 30 °C).

[0067] The water-soluble pillararene (m-TPEWP5) is water-soluble pillar[5]arene, and its structure is as follows:

[0068]

[0069] In Step 1: The concentration of the host-guest complex aqueous solution is 0.001 - 0.002 mM; the concentration of the photoinitiator solution is 0.0005 - 0.001 mM; the concentration of the receptor molecule solution is 0.00001 - 0.00002 mM.

[0070] In Step 3, the gelatin derivative includes methacrylated gelatin GelMA.

[0071] In Step 3, the conditions of light are: ultraviolet light with a wavelength of 350 - 380 nm, and the illumination time is 5 - 10 minutes.

[0072] In Step 1, the preparation method of the photoinitiator solution is as follows: Dissolve the photoinitiator in N,N-dimethylformamide solution to form a photoinitiator solution with a concentration of 0.0073 mM.

[0073] The photoinitiator is 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (I2959).

[0074] The structure of I2959 is as follows:

[0075]

[0076] In Step 1, the preparation method of the receptor molecule solution is as follows: Dissolve the receptor molecule in deionized water to form a receptor molecule solution with a concentration of 0.0073 mM.

[0077] The receptor molecule is selected from at least one of xanthene dyes, metal complexes or organic photosensitizers.

[0078] Preferably, the receptor molecule is eosin-Y (ESY), rose bengal or fluorescein.

[0079] Preferably, the receptor molecule is eosin-Y, and its structure is as follows:

[0080]

[0081] In step 3, in the aggregation-induced emission (AIE) supramolecular hydrogel, the concentrations of the components are as follows:

[0082] Host-guest complex A: 0.001 - 0.002 mM;

[0083] Photoinitiator: 0.0001 - 0.0002 mM;

[0084] Receptor molecule: 0.00001 - 0.00002 mM;

[0085] GelMA: 0.08 - 0.12 g / mL.

[0086] <The third aspect>

[0087] The present invention also provides an aggregation-induced emission (AIE) supramolecular hydrogel prepared by the preparation method as described above.

[0088] <The fourth aspect>

[0089] The present invention also provides an application of the aggregation-induced emission (AIE) supramolecular hydrogel as described above in photocatalysis.

[0090] The application is to catalyze the dehalogenation reaction of 2-bromo-1-phenylethanone and its derivatives in the aqueous phase and the benzylamine coupling reaction in acetonitrile solution in an aqueous solution.

[0091] Compared with the prior art, the present invention has the following beneficial effects:

[0092] (1) In the present invention, an amphiphilic molecule is synthesized as the guest, and at the same time, a water-soluble pillar[5]arene with AIE activity is used as the host molecule. Its cavity can combine with the amphiphilic guest molecule to form a stable host-guest complex, which can be used to construct an AIE-active hydrogel. Moreover, by encapsulating different amounts of eosin-Y, the fluorescence emission intensity can be effectively regulated, and it can also be used as a type II photosensitizer to generate reactive oxygen species.

[0093] (2) The hydrogel loaded with eosin-Y can effectively catalyze the dehalogenation reaction of 2-bromo-1-phenylethanone and its derivatives in aqueous phase and the coupling reaction of benzylamine and its derivatives in organic phase, and can be reused, which is a novel hydrogel catalyst with excellent performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0094] Other features, objects and advantages of the present invention will become more apparent by reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0095] Figure 1 1H NMR spectrum of compound A-1 in Example 1 1 ;

[0096] Figure 2 1H NMR spectrum of compound A-2 in Example 1 1 ;

[0097] Figure 3 1H NMR spectrum of compound A-3 in Example 1 1 ;

[0098] Figure 4 1H NMR spectrum of compound A-5 in Example 1 1 ;

[0099] Figure 5 1H NMR spectrum of compound A in Example 1 1 ;

[0100] Figure 6 1H NMR spectrum of compound A in Example 1 13 13C NMR spectrum;

[0101] Figure 7 High-resolution mass spectrum of compound A in Example 1;

[0102] Figure 8 Scanning electron microscope (SEM) photograph of the AIE supramolecular hydrogel in Example 2;

[0103] Figure 9 Fluorescence emission change spectrogram of the AIE supramolecular hydrogel encapsulating different contents of eosin-Y in Example 2;

[0104] Figure 10 Singlet oxygen generation ability diagram of the AIE supramolecular hydrogel loaded with eosin-Y in water in Example 2;

[0105] Figure 11 Structures of different substrates in the photocatalytic dehalogenation reaction test;

[0106] Figure 12 For calculating the yield of the first group of reactions1 1H NMR spectrum;

[0107] Figure 13 It is for calculating the yield of the second group of reactions 1 1H NMR spectrum;

[0108] Figure 14 It is for calculating the yield of the third group of reactions 1 1H NMR spectrum;

[0109] Figure 15 It is for calculating the yield of the fourth group of reactions 1 1H NMR spectrum;

[0110] Figure 16 It is for calculating the yield of the fifth group of reactions 1 1H NMR spectrum;

[0111] Figure 17 It is for calculating the yield of the sixth group of reactions 1 1H NMR spectrum;

[0112] Figure 18 It is the yield of the recycling of the AIE supramolecular material in the photocatalytic dehalogenation reaction;

[0113] Figure 19 It is the structures of different substrates in the photocatalytic benzylamine coupling reaction test;

[0114] Figure 20 It is for calculating the yield of the first group of reactions 1 1H NMR spectrum;

[0115] Figure 21 It is for calculating the yield of the second group of reactions 1 1H NMR spectrum;

[0116] Figure 22 It is for calculating the yield of the third group of reactions 1 1H NMR spectrum;

[0117] Figure 23 It is for calculating the yield of the fourth group of reactions 1 1H NMR spectrum;

[0118] Figure 24 It is for calculating the yield of the fifth group of reactions 1 1H NMR spectrum;

[0119] Figure 25 It is for calculating the yield of the sixth group of reactions 1 1H NMR spectrum;

[0120] Figure 26 It is the yield of the recycling of the AIE supramolecular material in the photocatalytic benzylamine coupling reaction. Detailed implementation mode

[0121] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. The following examples are implemented on the premise of the technical solution of the present invention, providing detailed implementation modes and specific operation processes, which will help those skilled in the art to further understand the present invention. It should be noted that the protection scope of the present invention is not limited to the following embodiments. Several adjustments and improvements made on the premise of the concept of the present invention all belong to the protection scope of the present invention.

[0122] Example 1 Preparation of amphiphilic guest molecule A

[0123] Specific synthesis steps of amphiphilic guest molecule A:

[0124]

[0125] (1) Synthesis of intermediate A-1: Under a nitrogen atmosphere, tetraethylene glycol (1.5 g, 7.7 mmol), triethylamine (0.5 mL, 3.85 mmol) and anhydrous dichloromethane (4 mL) were successively added to a reaction flask. After cooling the reaction system to 0 °C in an ice bath, acryloyl chloride (0.25 mL, 3.2 mmol) dissolved in 10 mL of anhydrous dichloromethane was slowly added dropwise to the reaction solution. After the addition was completed, the reaction solution was stirred at 0 °C for 1 h and then stirred at room temperature for 4 h. After the reaction was completed, the reaction was quenched with deionized water (20 mL), and the crude product was washed 3 times with saturated sodium chloride solution. The organic phase was dried with anhydrous sodium sulfate. The crude product was purified by silica gel column using dichloromethane / methanol (20:1, v / v) as the eluent to obtain a colorless oily product A-1 (0.34 g, 1.37 mmol, yield: 42.7%). The hydrogen spectrum data is as follows: 1 H NMR(400MHz,CDCl3,298K)δ6.42(d,J=17.3Hz,1H),6.15(dd,J=17.3,10.4Hz,1H),5.83(d,J=10.4Hz,1H),4.35–4.29(m,2H),3.77–3.70(m,4H),3.66(s,8H),3.63–3.56(m,2H).

[0126] (2) Synthesis of Intermediate A-2: Add dimethyl 5-hydroxyisophthalate (0.5 g, 2.38 mmol), anhydrous potassium carbonate (0.65 g, 4.76 mmol) and anhydrous acetonitrile (10 mL) into a reaction flask. The reaction solution was stirred at reflux at 80 °C for 30 minutes. Then, propargyl tribromide (0.22 mL, 2.85 mmol) was added to the reaction solution, and reflux was continued for 12 h. After the reaction was completed, the reaction mixture was concentrated in vacuo. The crude product was dissolved in ethyl acetate (50 mL) and washed successively with deionized water (3 × 20 mL) and saturated brine (3 × 20 mL). The organic phase was dried over anhydrous sodium sulfate and concentrated in vacuo. The obtained crude product was recrystallized by slow evaporation of a mixed solvent of dichloromethane and n-hexane (20 mL, 2:1, v / v) to obtain a white crystalline solid product A-2 (0.38 g, 1.54 mmol, yield: 64.7%). The 1H NMR data are as follows: 1 1H NMR (400 MHz, CDCl3, 298 K) δ 8.33 (s, 1H), 7.83 (s, 2H), 4.79 (s, 2H), 3.95 (s, 6H), 2.55 (s, 1H).

[0127] (3) Synthesis of Intermediate A-3: Add potassium hydroxide (0.26 g, 4.8 mmol), A-2 (0.3 g, 1.2 mmol) and pour methanol (5 mL) into a reaction flask. The reaction solution was refluxed at 65 °C for 12 h. After the reaction was completed, the reaction was quenched with deionized water. The reaction solution was washed with dichloromethane three times. The aqueous phase was acidified to pH < 2 with 6 M HCl to produce a white precipitate. The precipitate was filtered and collected, and the solid product was dried in vacuo to obtain a white solid product A-3 (0.238 g, 1.08 mmol, yield: 90%). The 1H NMR data are as follows: 1 1H NMR (400 MHz, DMSO-d6, 298 K) δ 13.30 (s, 2H), 8.11 (s, 1H), 7.72 (d, J = 1.0 Hz, 2H), 4.95 (d, J = 2.2 Hz, 2H), 3.64 (t, J = 2.1 Hz, 1H.

[0128] (4) Synthesis of Intermediate A-4: Under a nitrogen atmosphere, add compound A-3 (0.2 g, 0.91 mmol), anhydrous THF (2 mL) and anhydrous DMF (0.2 mL) into a reaction flask. The reaction system was cooled to 0 °C in an ice-water bath, and oxalyl chloride (0.23 g, 1.82 mmol) was slowly added. After the addition was completed, the reaction solution was stirred at 0 °C for 5 minutes, and then stirred at 30 °C for 3 hours. After the reaction was completed, the reaction solution was concentrated in vacuo to obtain a brown solid product A-4 (0.23 g, 0.90 mmol, yield: 99%).

[0129] (5) Synthesis of Intermediate A-5: Under a nitrogen atmosphere, compound A-1 (0.56 g, 2.25 mmol), triethylamine (0.15 mL), and anhydrous dichloromethane (2 mL) were added to a reaction flask. The reaction system was cooled to 0 °C in an ice-water bath, and B-4 (0.23 g, 0.90 mmol) dissolved in 2 mL of dichloromethane was slowly added. After the addition, the reaction solution was stirred at room temperature for 12 h. After the reaction was completed, the reaction solution was filtered and concentrated under vacuum. The crude product was purified by silica gel column chromatography using dichloromethane / methanol (15:1, v / v) as the eluent to obtain a colorless oily product A-5 (0.34 g, 0.32 mmol, yield: 35%). The 1H NMR data are as follows: 1 1H NMR (400 MHz, CDCl3, 298 K) δ 8.30 (s, 1H), 7.80 (s, 2H), 6.38 (d, J = 17.4 Hz, 2H), 6.10 (dd, J = 17.2, 10.4 Hz, 2H), 5.79 (d, J = 10.4 Hz, 2H), 4.75 (s, 2H), 4.46 (t, J = 5.2 Hz, 4H), 4.26 (t, J = 5.0 Hz, 4H), 3.80 (t, J = 5.2 Hz, 4H), 3.71–3.59 (m, 20H), 2.57 (s, 1H).

[0130] (6) Synthesis of Amphiphilic Guest Molecule A: Under a nitrogen atmosphere, sodium azidosulfonate (0.046 g, 0.2 mmol), tris-(benzyltriazolylmethyl)amine (0.01 g, 0.017 mmol), copper(II) tetraethylammonium hexafluorophosphate (0.006 g, 0.017 mmol), and anhydrous methanol (3 mL) were added to a reaction flask. A dichloromethane solution (3 mL) of compound A-5 (0.12 g, 0.18 mmol) was added to the reaction solution, and the mixture was stirred at room temperature for 24 h. After the reaction was completed, the reaction solution was concentrated under vacuum. The crude product was purified by silica gel column chromatography using dichloromethane / methanol (20:1, v / v) as the eluent to obtain a green oily product A (0.128 g, 0.14 mmol, yield: 80.1%). The 1H NMR, 13C NMR, and high-resolution mass spectrometry data are as follows: 11H NMR (400 MHz, D2O, 298 K) δ 8.10 (s, 1H), 8.04 (s, 1H), 7.68 (s, 2H), 6.30 (d, J = 17.2 Hz, 2H), 6.03 (dd, J = 17.2, 10.5 Hz, 2H), 5.86 (d, J = 10.4 Hz, 2H), 5.22 (s, 2H), 4.49–4.42 (m, 4H), 4.41–4.34 (m, 2H), 4.16–4.09 (m, 4H), 3.90–3.82 (m, 4H), 3.72–3.68 (m, 4H), 3.65–3.57 (m, 12H), 3.56–3.53 (m, 4H), 2.84–2.76 (m, 2H), 1.83 (t, J = 7.5 Hz, 2H), 1.63 (t, J = 7.6 Hz, 2H), 1.34 (t, J = 7.5 Hz, 2H), 1.24–1.18 (m, 2H). 13 13C NMR (100 MHz, D2O, 298 K) δ 168.03, 166.55, 156.85, 132.32, 131.34, 127.12, 122.77, 121.36, 69.89, 69.70, 69.57, 68.42, 68.30, 64.84, 63.76, 61.52, 50.79, 50.36, 29.13, 27.00, 25.04, 23.76. HR-ESI-MS: m / z [M-Na] - calculated for [C 39 H 56 N3O 18 S] - 886.3280, found 886.3242。

[0131] Example 2. Supramolecular hydrogel with aggregation-induced emission effect (AIE supramolecular hydrogel)

[0132] The supramolecular hydrogel with aggregation-induced emission effect (AIE supramolecular hydrogel) is prepared by first mixing AIE water-soluble pillar[5]arene B and the amphiphilic guest A prepared in Example 1 to obtain a host-guest complex; then copolymerizing the host-guest complex with methacrylated gelatin GelMA. The specific steps are as follows:

[0133] 1. At room temperature, prepare an aqueous solution of amphiphilic guest with a concentration of 0.073 mM and an aqueous solution of AIE water-soluble pillar[5]arene B with a concentration of 0.073 mM respectively. Inject the aqueous solution of amphiphilic guest into the aqueous solution of AIE water-soluble pillar[5]arene, and mix evenly to obtain a host-guest complex solution.

[0134] AIE water-soluble pillar[5]arene (for the preparation method, see CN 114702952B), and its structural formula is as follows:

[0135]

[0136] 2. Prepare an N,N-dimethylformamide solution with a concentration of 0.0075 mM of photoinitiator I2959 and an aqueous solution with a concentration of 0.00075 mM of eosin-Y at room temperature.

[0137] 3. Take two volumes of the host-guest complex aqueous solution, one volume of the I2959 solution, one volume of the eosin-Y aqueous solution, and one volume of deionized water and mix them evenly; add methacryloylated gelatin GelMA to the mixed solution; after complete dissolution, mix evenly, inject it into a mold, and irradiate it with a 365-nm ultraviolet lamp for 8 minutes to obtain a supramolecular hydrogel with aggregation-induced emission effect (AIE supramolecular hydrogel). In the final AIE supramolecular hydrogel, the concentration of the host-guest complex ( ) is 0.0015 mM, the concentration of I2959 is 0.00015 mM, the concentration of eosin-Y is 0.000015 mM, and the concentration of GelMA is 0.1 g / mL.

[0138] As Figure 8 shown, the scanning electron microscope (SEM) photograph of the AIE supramolecular hydrogel prepared in this example;

[0139] The supramolecular hydrogel with aggregation-induced emission effect (AIE supramolecular hydrogel) encapsulating different contents of eosin-Y is obtained by first mixing AIE water-soluble pillar[5]arene B and the amphiphilic guest A prepared in Example 1 to prepare a host-guest complex; then adding the host-guest complex to different contents of eosin-Y and methacryloylated gelatin GelMA for copolymerization. In the final AIE supramolecular hydrogel, the concentration of the host-guest complex is 0.0015 mM, the concentration of I2959 is 0.00015 mM, the concentration of eosin-Y is 0 - 0.000015 mM, and the concentration of GelMA is 0.1 g / mL.

[0140] As Figure 9 shown, the AIE supramolecular hydrogel encapsulating different contents of eosin-Y prepared in this example undergoes an effective FRET process under 365-nm light excitation.

[0141] Performance test example

[0142] 1. Test the ability of the AIE supramolecular hydrogel prepared in Example 2 to generate singlet oxygen:

[0143] 9,10-anthracenediyl-bis(methylene)dimalonic acid (ABDA) was used as an indicator to detect the generation of singlet oxygen. The prepared AIE supramolecular hydrogel (where the host-guest complex content was 0.0015 mmol) was added to 1.5 mL of a standard solution with an ABDA concentration of 0.2 mM. The absorbance of the sample solution was detected using a UV-visible spectrophotometer, and the generation of singlet oxygen was detected based on the change in the absorbance of ABDA. Figure 10 As shown, the decrease in the absorbance of ABDA indicates the process of singlet oxygen generation caused by the AIE supramolecular hydrogel, that is, it indicates that the hydrogel can generate singlet oxygen.

[0144] 2. Test of AIE supramolecular hydrogel materials for efficient photocatalytic dehalogenation reaction

[0145] Using the AIE supramolecular hydrogel as a photocatalyst, the dehalogenation reaction of 2-bromo-1-phenylethanone with different substituents on the benzene ring was catalyzed.

[0146] The catalytic reaction conditions were as follows: bromoacetophenone (20 mg, 0.1 mmol), Hantzsch ester (28 mg, 0.11 mmol), N,N-diisopropylethylamine (DIPEA, 35 μL, 0.2 mmol), the equivalent of eosin-Y encapsulated in the AIE supramolecular hydrogel was 0.5% mmol of the substrate, the reaction was carried out in water (1 mL), under a 365 nm UV lamp (32 W), at room temperature, under nitrogen protection, and the reaction was carried out for 2 hours. The product yield was obtained from 1 the 1H NMR spectrum.

[0147] The structures of different substrates are as Figure 11 shown. The yields under different reaction conditions are shown in Table 1. The 1H NMR spectrum for calculating the product yield is as 1 shown. Figures 12 - 17 as

[0148] Table 1

[0149]

[0150] Where:

[0151] refers to: AIE supramolecular hydrogel

[0152] HGGelMA without ESY refers to: AIE supramolecular hydrogel with 0 content of encapsulated eosin-Y

[0153] The results show that the introduction of the AIE supramolecular hydrogel prepared in the present invention greatly increases the reaction efficiency, and high yields of all substrates are obtained within 2 hours. Since the structure of this hydrogel is stable and not easily soluble, it can be reused multiple times, and the catalytic activity does not significantly decrease during two cycles. Catalyst recovery method: Filter the reaction solution after the reaction to obtain the solid AIE supramolecular hydrogel ( ), wash it three times with deionized water to obtain the recovered catalyst. The yields of recycling are as shown in Figure 18 , and the yields fluctuate within the range of 81% to 99%, which is within the normal measurement error range.

[0154] 3. Test of AIE supramolecular hydrogel materials for efficient photocatalytic oxidative coupling reaction

[0155] Using the AIE supramolecular hydrogel as a photocatalyst, the oxidative coupling reaction of benzylamine with different substituents on the benzene ring was catalyzed. The catalytic reaction conditions were as follows: benzylamine (0.02 mL, 0.18 mmol), the equivalent of eosin-Y encapsulated in the AIE supramolecular hydrogel was 0.03% mmol of the substrate, the reaction was carried out in acetonitrile (1 mL), under a 365 nm ultraviolet lamp (32 W), at room temperature, in an oxygen atmosphere, and the reaction was for 12 hours. The product yield was obtained from 1 1H NMR spectra.

[0156] The structures of different substrates are as shown in Figure 19 . The yields under different reaction conditions are shown in Table 2. The 1H NMR spectra for calculating the product yields are as shown in 1 1H NMR Figures 20 - 25 .

[0157] Table 2

[0158]

[0159]

[0160] Among them:

[0161] refers to: AIE supramolecular hydrogel

[0162] HGGelMA without ESY refers to: AIE supramolecular hydrogel with 0 content of encapsulated eosin-Y

[0163] The results show that the introduction of the AIE supramolecular hydrogel greatly increases the reaction efficiency, and high yields of all substrates are obtained within 12 hours. Since the structure of this hydrogel is stable and not easily soluble, it can be reused multiple times, and the catalytic activity does not significantly decrease during two cycles. Catalyst recovery method: Filter the reaction solution after the reaction to obtain the solid AIE supramolecular hydrogel ( ), washed three times with deionized water to obtain the recovered catalyst. The recycling yield is as Figure 26 shown, and the yield fluctuates in the range of 26% to 69%, which is within the normal measurement error range.

[0164] The present invention provides a photocatalytic system based on supramolecular hydrogel. This system combines supramolecular chemistry, FRET mechanism and photocatalytic technology, and exhibits efficient, stable and environmentally friendly photocatalytic performance. This system can not only catalyze various types of reactions, but also be recovered from the reaction mixture through a simple washing procedure, with good recyclability and reusability. The present invention provides new ideas and methods for the development of photocatalytic technology and has broad application prospects.

[0165] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. An amphiphilic guest molecule, characterized in that, The structural formula of the amphiphilic guest molecule is as described in Formula (1): Wherein, n is 2 - 10, and the number of carbon atoms m of the alkyl chain is 6 - 18.

2. The amphiphilic guest molecule according to claim 1, wherein, The structural formula of the amphiphilic guest molecule is as shown in Formula A:

3. A preparation method of an amphiphilic guest molecule, characterized in that, It includes the following steps: (1) React tetraethylene glycol with acryloyl halide in the presence of an acid-binding agent in a first organic solvent to obtain intermediate A-1; (2) React dimethyl 5-hydroxyisophthalate with propargyl halide under alkaline conditions in a second organic solvent to obtain intermediate A-2; (3) Hydrolyze intermediate A-2 in methanol under alkaline conditions to obtain intermediate A-3; (4) React intermediate A-3 with an acyl halide reagent in a mixed solvent of tetrahydrofuran and N,N-dimethylformamide to carry out an acyl halide reaction to obtain intermediate A-4; (5) React intermediate A-1 with intermediate A-4 in the presence of an acid-binding agent in dichloromethane to carry out a condensation reaction to obtain intermediate A-5; (6) Carry out a click chemical reaction on intermediate A-5 and an azide compound in the presence of a copper catalyst and a ligand in a mixed solvent of dichloromethane and methanol to obtain the amphiphilic guest molecule, denoted as amphiphilic guest molecule A.

4. The preparation method according to claim 3, characterized in that, In step (1), the molar ratio of tetraethylene glycol to acryloyl halide is 1:0.4 - 0.5; And / or, in step (2), the molar ratio of dimethyl 5-hydroxyisophthalate to propargyl halide is 1:1.0 - 1.5; And / or, in step (3), the molar ratio of intermediate A-2 to the base is 1:4.0; And / or, in step (4), the molar ratio of intermediate A-3 to the acyl halide reagent is 1:2.0 - 2.5; And / or, in step (5), the molar ratio of compound A-4 to compound A-1 is 1:2.0 - 2.5; And / or, in step (6), the molar ratio of intermediate A-5 to the azide compound is 1:1.0 - 1.

5.

5. The preparation method according to claim 3, characterized in that, In step (1), the acryloyl halide is acryloyl chloride, the acid-binding agent is triethylamine, and the first organic solvent is dichloromethane; In step (2), the propargyl halide is 1,1,1-tribromopropyne, the base is anhydrous potassium carbonate, and the second organic solvent is acetonitrile; And / or, in step (3), the base is potassium hydroxide; And / or, in step (4), the acyl halide reagent is oxalyl chloride; And / or, in step (5), the acid-binding agent is triethylamine; And / or, in step (6), the azide compound is sodium azidosulfonate, the copper catalyst is copper(II) tetrafluoroborate acetonitrile complex, and the ligand is tris-(benzyltriazolylmethyl)amine.

6. The preparation method according to claim 3, characterized in that, In step (1), the esterification reaction is carried out at 0℃ - 30℃ to room temperature, and the reaction time is 4 - 6 hours; In step (2), the etherification reaction is carried out under reflux conditions at 80℃ - 85℃, and the reaction time is 12 - 14 hours; In step (3), the hydrolysis reaction is carried out under reflux conditions at 60℃ - 75℃, and the reaction time is 12 - 14 hours; In step (4), the acyl halide reaction is carried out at -15℃ - 30℃, and the reaction time is 3 - 5 hours; In step (6), the click chemical reaction is carried out at room temperature, and the reaction time is 24 - 28 hours.

7. A preparation method of an aggregation-induced emission supramolecular hydrogel, characterized in that, Comprising the following steps: Step 1: Prepare an aqueous solution of the host-guest complex, a photoinitiator solution, and a receptor molecule solution respectively; the host-guest complex is obtained by preparing with a water-soluble pillararene and the amphiphilic guest molecule described in claim 1 or 2; Step 2: Mix the aqueous solution of the host-guest complex, the photoinitiator solution, the receptor molecule solution and water according to a volume ratio of (1.5 - 2.5):(0.5 - 1.5):(0.5 - 1.5):(0.5 - 1.5) to obtain a mixed solution; Step 3: Add a gelatin derivative to the mixed solution, inject it into a mold after dissolution, and crosslink under light to form the aggregation-induced emission supramolecular hydrogel.

8. The preparation method according to claim 7, wherein, In Step 1: The aqueous solution of the host-guest complex is obtained by a method comprising the following steps: A. Dissolve the amphiphilic guest molecule described in claim 1 or 2 in water to form an amphiphilic guest molecule A solution with a concentration of 0.01 - 0.1 mM; dissolve the water-soluble pillararene in water to form a water-soluble pillararene B solution with a concentration of 0.01 - 0.1 mM; B. Mix the amphiphilic guest molecule A solution and the water-soluble pillararene B solution to form an aqueous solution of the host-guest complex.

9. An aggregation-induced emission supramolecular hydrogel obtained by the preparation method described in claim 7 or 8.

10. Use of the aggregation-induced emission supramolecular hydrogel according to claim 9 in a photocatalytic reaction, characterized in that, The application is a catalytic dehalogenation reaction and / or an oxidative coupling reaction of benzylamine.

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