A photosensitive material TPE-CHO and a covalent organic framework nanomaterial prepared based on the same

Abstract

The present invention belongs to the technical field of new nanomaterials, and relates to a photosensitive material TPE-CHO and a covalent organic framework nanomaterial prepared based on the same. First, a photosensitive material TPE-CHO: #imgabs0# is prepared, which has a strong electron acceptor-donor-acceptor structure and provides good optical properties. Compared with most organic molecules, it has high photostability, a wide light absorption range and a high molar extinction coefficient, which greatly supplements the shortcomings of current photochemical functional materials. It is then reacted with COF to obtain a covalent organic framework nanomaterial, which can produce under light. 1 O2 has strong photosensitivity, and its synthesis process is simple and can be completed at room temperature.

Description

Technical Field

[0001] The present invention belongs to the technical field of new nanomaterials and relates to a photosensitive material TPE-CHO and a covalent organic framework nanomaterial prepared based on the photosensitive material. Specifically, the present invention relates to a new organic molecule (TPE-CHO) with high photosensitivity, which serves as a building block of a covalent organic framework nanomaterial (TPE-COF) and is covalently cross-linked with tris(4-aminophenyl)amine (TAPA) for the preparation of functionalized TPE-COF. Background Art

[0002] In photochemical reactions, there is a class of molecules that absorb photons and transfer energy to molecules that cannot absorb photons, promoting chemical reactions in them, while remaining uninvolved and returning to their original state. These molecules are called photosensitizers. Currently, small organic molecules are the primary source of photosensitizers. However, small molecule photosensitizers (such as porphyrins and phthalocyanines) often suffer from aggregation-induced quenching (ACQ), which hinders their photosensitivity. Therefore, the development of new and efficient photosensitizers is urgently needed.

[0003] Covalent organic framework (COF) materials, due to their regular structure, large surface area, and porosity, have become a hot topic in the field of new materials research. They hold significant research value in fields such as catalysis, gas separation, and drug delivery. Compared to small-molecule photosensitizers, COF materials can isolate small photosensitizer molecules and prevent their aggregation, thereby overcoming the drawbacks of small-molecule photosensitizers such as ACQ. Their large conjugated structure also provides them with a narrow band gap, broad absorption, and excellent photothermal stability. Furthermore, the abundant porosity of COF materials facilitates the free transport of oxygen and reactive oxygen species (ROS), enhancing their photosensitivity to a certain extent. Chinese patent CN 112679685 B discloses a conjugated organic framework material (COFTA) based on anthracene units and its preparation method. However, the process requires a high-temperature reaction. The prepared material dimerizes under UV light to form a dianthracene structure and depolymerizes under visible light, resulting in poor overall stability. Summary of the Invention

[0004] In response to the problems existing in current photosensitive materials, the present invention first prepares a photosensitivity organic molecule TPE-CHO, which has a strong electron acceptor-donor-acceptor structure and provides good optical properties. Compared with most organic molecules, it has high photostability, a wide light absorption range and a high molar extinction coefficient, which greatly supplements the shortcomings of current photochemical functional materials. It is then reacted with TAPA to obtain a covalent organic framework nanomaterial, which can produce under light. 1 O2 has strong photosensitivity, and its synthesis process is simple and can be completed at room temperature.

[0005] The proposal of this application is:

[0006] A photosensitive material TPE-CHO, the structure of which is shown in Formula I;

[0007]

[0008] Formula I.

[0009] The preparation method of the above-mentioned photosensitive material TPE-CHO comprises the following steps:

[0010]

[0011] (1) Compound 1 and Compound 2 are added to solvent 1, palladium acetate and tri(o-methylphenyl)phosphine are added, and the mixture is reacted under a protective atmosphere to obtain Compound 3, which is then purified and used for the next step;

[0012] (2) The purified compound 3 and 4-bromobenzaldehyde were dissolved in solvent 2 and reacted. Ether was added to precipitate the crude product, which was then purified to obtain TPE-CHO.

[0013] Preferably, in step (1), solvent 1 is triethylamine / DMF mixed at a ratio of V:V = 2:1.

[0014] Preferably, the reaction conditions under the protective atmosphere in step (1) are heating to 70-90° C. under N 2 atmosphere and reacting for more than 10-15 h.

[0015] Preferably, the purification process in step (1) is as follows: after the reaction is completed, the organic phase is extracted with dichloromethane, the solvent is evaporated, and then separation is performed using rapid column chromatography.

[0016] Preferably, in step (2), solvent 2 is DMF, and the reaction conditions are 90-110°C.

[0017] Another object of the present invention is to protect a covalent organic framework nanomaterial prepared based on the photosensitive material TPE-CHO, the structural formula of which is shown in Formula II;

[0018]

[0019] Formula II.

[0020] Furthermore, the preparation process of the nanomaterial is as follows: after TPE-CHO is dispersed in acetonitrile, PVP, TAPA and glacial acetic acid are added, stirred, allowed to stand, and then p-anisaldehyde is added, and the stirring reaction is continued; and the nanomaterial is obtained by centrifugation and washing.

[0021] Furthermore, the nanomaterial has a diameter of 140±10 nm and carries a positive charge.

[0022] Beneficial effects of the present invention

[0023] 1. A new organic molecule (TPE-CHO) with excellent light absorption ability and ultra-high photosensitivity was synthesized;

[0024] 2. A new type of small-sized covalent organic framework nanomaterial (TPE-COF) was synthesized at room temperature;

[0025] 3. Compared with small molecule photosensitizers, TPE-COF has abundant pores (easy to transfer oxygen and ROS), and its large conjugated structure gives it a narrow band gap, wide absorption and good photothermal stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Figure 2 is a synthetic process diagram of TPE-CHO;

[0027] Figure 2 is the ESI-MS image of TPE-CHO;

[0028] Figure 3 For TPE-CHO 1 H NMR spectrum;

[0029] Figure 4 The synthetic process diagram of TPE-COF;

[0030] Figure 5 UV-visible spectra (a) and fluorescence emission spectra (b) of TPE-CHO and TPE-COF. TEM image, scale bar = 100 nm (c) and N2 adsorption isotherm of TPE-COF (d);

[0031] Figure 6 Hydrodynamic particle size distribution (a), zeta potential (b), Fourier transform infrared spectroscopy (FT-IR) (c), pore size distribution (d);

[0032] Figure 7 UV-visible spectra of ABDA in (a) TPE-CHO, (b) Rose Bengal, and (c) H₂O aqueous solutions under xenon lamp (λ = 320–780 nm). (d) ESR spectra of a mixed aqueous solution of ABDA (24.4 mg / mL) and TPE-CHO (10 µM) under xenon lamp (λ = 320–780 nm).

[0033] Figure 8 ESR spectra of a mixed aqueous solution of TEMP (24.4 mg / mL) and TPE-COF (100 µg / mL) under xenon lamp (λ = 320 ~ 780 nm) irradiation;

[0034] Figure 9This is the TGA analysis diagram of TPE-COF. DETAILED DESCRIPTION

[0035] Preparation of compounds 1 and 2 used in this application:

[0036] Synthesis of compound 1:

[0037] 4,4'-Dibromobenzophenone (1.7 g, 5 mmol) and zinc powder (3.90 g, 60 mmol) were placed in a two-necked round-bottom flask. Under nitrogen protection, tetrahydrofuran (100 mL) and titanium tetrachloride (3.3 mL, 30.0 mmol) were added and stirred at 2°C. The reaction solution was then heated to 80°C under nitrogen for 24 h. After cooling to room temperature, a 10% aqueous potassium carbonate solution was added to quench the reaction. The organic phase was extracted and separated with dichloromethane, and the solvent was dried by rotary evaporation. Flash column chromatography afforded the pale pink product 1 in an approximately 80% yield (2.58 g, 4 mmol).

[0038] Synthesis of compound 2:

[0039] 4-Methylquinoline (2.86 g, 1 equivalent) and anhydrous iron(III) chloride (0.648 g, 0.2 equivalent) were dissolved in DMF (100 mL) and reacted with tert-butyl peroxide (7.72 g, 70%, 3 equivalents) at 140°C for 5 h. The organic phase was extracted with dichloromethane, and the solvent was then dried by spin drying. Finally, product 2 was obtained by flash column chromatography in a yield of approximately 39% (1.2 g, 7.8 mmol).

[0040] Example 1

[0041] The preparation method of the photosensitive material TPE-CHO is as follows: Figure 1 As shown, the following steps are included:

[0042] (1) Compound 1 (800 mg, 1 equivalent) and compound 2 (1.156 g, 6 equivalents) were dissolved in a triethylamine / DMF mixture (10 mL of triethylamine and 5 mL of DMF). 27.8 mg of palladium acetate and 37.8 mg of tri(o-methylphenyl)phosphine were added. The mixture was heated to 80°C under a nitrogen atmosphere for 12 h. After the reaction, the organic phase was extracted with dichloromethane and the solvent was evaporated. To purify the crude product, flash column chromatography was used to obtain the yellow product 3 in a yield of approximately 60% (704 mg, 0.75 mmol).

[0043] (2) Molecule 3 (600 mg, 1 eq) and 4-bromobenzaldehyde (1.01 g, 8 eq) were dissolved in DMF (100 mL) and heated to 100 °C. After 12 h, ether was added to the reaction solution to precipitate the crude product, which was purified to obtain the red product (TPE-CHO) in approximately 95% yield (1.06 g, 0.61 mmol).

[0044] 1 H NMR (400 MHz, DMSO-d6)

[0045] δ10.02 (s, 1H), 9.70 (d, J = 6.4 Hz, 1H), 9.11 (d, J = 8.6 Hz, 1H), 8.71 (d, J = 6.4 Hz, 1H), 8.42(d, J = 16.0 Hz, 1H), 8.37 (d, J = 9.2 Hz, 1H), 8.29 (d, J = 15.6 Hz, 2H), 8.19 (t, J = 7.9 Hz, 1H), 7.99 (d, J = 8.0 Hz, 3H), 7.95 (d, J = 7.9 Hz, 1H), 7.58 (d, J = 7.9 Hz, 2H), 7.34 (d, J = 7.8 Hz,2H), 6.46 (s, 2H). ESI-MS: m / z calcd for C 102 H 76 N4O4 4+ , 355.397; found: 355.16.

[0046] Detailed synthetic route of TPE-CHO ( Figure 1 ), the product was characterized by ESI-MS and 1H-NMR ( Figure 2 and Figure 3 ).

[0047] The photophysical properties of the successfully synthesized TPE-CHO were studied. The maximum absorption peak of TPE-CHO appears at 450 nm ( Figure 5 a), the maximum emission peak appears at 740 nm ( Figure 5 b) These optical properties provide the possibility for the photosensitivity of TPE-CHO.

[0048] d-singlet oxygen of TPE-CHO ( 1 The photosensitivity of TPE-CHO was determined by 9,10-anthracenediylbis(methylene)dimalonic acid (ABDA, 1O2 indicator) to test, ABDA can be 1 O2 selectively oxidizes to provide peroxides, which reduces absorbance. ABDA is a typical molecular probe used to detect 1 O2 production. TPE-CHO (1 µM) and ABDA (50 µM) solutions were mixed and irradiated with a xenon lamp (λ = 320 ~ 780 nm). The absorbance of the solution was measured every 10 s using a Hitachi U-4100 UV / Vis. In the solution containing Rose Bengal, the rate of decrease of TPE-CHO was significantly faster than that of the commercial photosensitizer Rose Bengal ( Figure 7 bc), indicating that TPE-CHO is photosensitivity and can be effectively activated by light sources.

[0049] Example 2

[0050] The preparation method of the photosensitive material TPE-CHO comprises the following steps:

[0051] (1) Compound 1 (800 mg, 1 equivalent) and compound 2 (1.156 g, 6 equivalents) were dissolved in a triethylamine / DMF mixture (10 mL of triethylamine and 5 mL of DMF). 27.8 mg of palladium acetate and 37.8 mg of tri(o-methylphenyl)phosphine were added. The mixture was heated to 70°C under a nitrogen atmosphere for 15 h. After the reaction, the organic phase was extracted with dichloromethane and the solvent was evaporated. To purify the crude product, flash column chromatography was used to obtain the yellow product 3 in a yield of approximately 57% (663 mg, 0.70 mmol).

[0052] Synthesis of TPE-CHO:

[0053] Molecule 3 (600 mg, 1 eq) and 4-bromobenzaldehyde (1.01 g, 8 eq) were dissolved in DMF (100 mL) and heated to 90°C. After 15 h, diethyl ether was added to the reaction solution to precipitate the crude product, which was purified to afford the red product (TPE-CHO) in 93% yield (1.02 g, 0.59 mmol).

[0054] Example 3

[0055] The preparation method of the photosensitive material TPE-CHO comprises the following steps:

[0056] (1) Compound 1 (800 mg, 1 equivalent) and compound 2 (1.156 g, 6 equivalents) were dissolved in a triethylamine / DMF mixture (10 mL of triethylamine and 5 mL of DMF). 27.8 mg of palladium acetate and 37.8 mg of tri(o-methylphenyl)phosphine were added. The mixture was heated under a nitrogen atmosphere for 12 h. After the reaction, the organic phase was extracted with dichloromethane and the solvent was evaporated. To purify the crude product, flash column chromatography was used to obtain the yellow product 3 in a yield of approximately 62% (728 mg, 0.77 mmol).

[0057] (2) Molecule 3 (600 mg, 1 eq) and 4-bromobenzaldehyde (1.01 g, 8 eq) were dissolved in DMF (100 mL) and heated to 100–120 °C. After 12 h, ether was added to the reaction solution to precipitate the crude product, which was purified to obtain the red product (TPE-CHO) in approximately 94% yield (1.04 g, 0.6 mmol).

[0058] Example 4

[0059] The preparation method of the covalent organic framework nanomaterial TPE-COF prepared based on the photosensitive material TPE-CHO in Example 1 comprises the following steps:

[0060] After dispersing TPE-CHO (50 mg, 28.8 µmol) in acetonitrile (20 mL), PVP (20 mg, Mw = 10,000), TAPA (13 mg, 115.2 µmol), and glacial acetic acid (900 µL) were added. The mixture was stirred for 48 h, allowed to stand for 48 h, and then p-anisaldehyde (100 µL) was added to the reaction system. Stirring was continued for 2.5 h to terminate the reaction. Finally, the TPE-COF was centrifuged and washed with acetonitrile to obtain an orange powder.

[0061] Characterization of TPE-COF:

[0062] TPE-COF is approximately spherical with a diameter of 140±10 nm ( Figure 5 c. Figure 6 a), positively charged ( Figure 6 b).

[0063] Fourier transform infrared (FT-IR) spectroscopy showed that the -1 and 3325 cm -1 The peaks associated with free -CHO and -NH2 groups at 1603 cm -1 A new peak appeared at 1601 cm-1, corresponding to the stretching band of C=N (different from the 1601 cm-1 peak in TPE-CHO). -1The C=N peak at the position of the C=N peak indicates that the -CHO and -NH2 groups are successfully condensed ( Figure 6 c).

[0064] In order to further demonstrate its porosity and specific surface area, N2 adsorption-desorption experiments were carried out ( Figure 5 c). The results show that the Brunauer-Emmet-Teller (BET) specific surface area of ​​TPE-COF is 687.2±1.9 m 2 / g, pore size is about 3.7nm ( Figure 5 d. Figure 6 d) In Figure 9 It can be observed that TPE-COF exhibits a slight weight loss before 250˚C, which is due to its high stability.

[0065] TPE-COF production 1 ESR measurement of O2 capacity. Electron spin resonance (ESR) was used to measure the O2 capacity under photosensitization. 1 The generation of O2, of which 2,2,6,6-tetramethyl-4-piperidinol (TEMP) is 1 O2 capture agent.

[0066] A mixed solution of TPE-COF (100 μL, 100 μg / mL) and TEMP (3 μL, 24.4 mg / mL) was irradiated under a xenon lamp (λ = 320 ~ 780 nm). Subsequently, the ESR spectrum was measured using a Japanese jesfa200 ESR spectrometer after irradiation for 5 min. Figure 8 It can be seen that the representative ESR signal has an intensity ratio of 1:1:1, indicating that TPE-COF can produce 1 O2, has strong photosensitivity.

[0067] Example 5

[0068] The preparation method of the covalent organic framework nanomaterial TPE-COF prepared based on the photosensitive material TPE-CHO in Example 2 comprises the following steps:

[0069] After dispersing TPE-CHO (50 mg, 28.8 µmol) in acetonitrile (20 mL), PVP (20 mg, Mw = 10,000), TAPA (13 mg, 115.2 µmol), and glacial acetic acid (900 µL) were added. The mixture was stirred for 48 hours, allowed to stand for 40 hours, and then p-anisaldehyde (100 µL) was added to the reaction system. Stirring continued for 2 hours to terminate the reaction. Finally, the TPE-COF was centrifuged and washed with acetonitrile to obtain an orange powder.

[0070] Example 6

[0071] The preparation method of the covalent organic framework nanomaterial TPE-COF prepared based on the photosensitive material TPE-CHO in Example 3 comprises the following steps:

[0072] After dispersing TPE-CHO (50 mg, 28.8 µmol) in acetonitrile (20 mL), PVP (20 mg, Mw = 10,000), TAPA (13 mg, 115.2 µmol), and glacial acetic acid (900 µL) were added. The mixture was stirred for 48 h, allowed to stand for 60 h, and then p-anisaldehyde (100 µL) was added to the reaction system. Stirring was continued for 3 h to terminate the reaction. Finally, the TPE-COF was centrifuged and washed with acetonitrile to obtain an orange powder.

Claims

1. A covalent organic framework nanomaterial prepared based on the photosensitive material TPE-CHO, characterized in that: The structural formula of the nanomaterial is shown in Formula II; Formula II; The preparation process of the nanomaterial is as follows: after TPE-CHO is dispersed in acetonitrile, PVP, TAPA and glacial acetic acid are added, stirred, allowed to stand, and then p-anisaldehyde is added, and the stirring reaction is continued; centrifugation and washing are performed to obtain the nanomaterial. The structure of the photosensitive material TPE-CHO is shown in Formula Ⅰ; Formula I.

2. The covalent organic framework nanomaterial according to claim 1, characterized in that The nanomaterial has a diameter of 140±10 nm and carries a positive charge.

3. The covalent organic framework nanomaterial according to claim 1, characterized in that The preparation method of the photosensitive material TPE-CHO comprises the following steps: (1) Compound 1 and Compound 2 are added to solvent 1, palladium acetate and tri(o-methylphenyl)phosphine are added, and the mixture is reacted under a protective atmosphere to obtain Compound 3, which is then purified and used for the next step; (2) The purified compound 3 and 4-bromobenzaldehyde were dissolved in solvent 2 and reacted. Ether was added to precipitate the crude product, which was then purified to obtain TPE-CHO.

4. The covalent organic framework nanomaterial according to claim 3, characterized in that In the step (1), solvent 1 is triethylamine / DMF mixed at a ratio of V:V = 2:

1.

5. The covalent organic framework nanomaterial according to claim 3, characterized in that The reaction conditions under the protective atmosphere in step (1) are heating to 70-90° C. under N 2 atmosphere and reacting for 10-15 h.

6. The covalent organic framework nanomaterial according to claim 3, characterized in that The purification process in step (1) is as follows: after the reaction is completed, the organic phase is extracted with dichloromethane, the solvent is evaporated, and then separation is performed using rapid column chromatography.

7. The covalent organic framework nanomaterial according to claim 3, characterized in that In the step (2), the solvent 2 is DMF, and the reaction conditions are 90-110°C.

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