Synthesis of a class of tpe backbone structure molecular cage
By synthesizing TPE framework molecular cages and utilizing the reaction of tetrar-based tetraphenylethylene and cyclohexanediamine, the problem of decreased luminescence intensity of fluorescent materials at high concentrations was solved, achieving high quantum yield and photostability, thus expanding the application potential of fluorescent probes.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHONGYUAN ENGINEERING COLLEGE
- Filing Date
- 2023-07-24
- Publication Date
- 2026-06-05
Smart Images
Figure CN117050252B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of organic compound synthesis technology, specifically relating to a method for synthesizing a type of TPE framework molecular cage. Background Technology
[0002] Porous materials have attracted much attention due to their unique properties, including zeolites, metal-organic frameworks, covalent organic frameworks, and porous organic polymers. Organic cage-like compounds are materials with permanent cavities formed through the interactions between discrete molecules; their structure is a solid structure formed by dispersed molecules aggregated through intermolecular forces. Organic molecular cages contain nanoscale cavities, giving them a large specific surface area, and their good dispersibility and stable cavity structure have made them a focus of attention.
[0003] Fluorescence is the phenomenon where molecules, atoms, or groups of atoms emit light of a fixed wavelength after being excited by external energy, undergoing energy level transitions. Fluorescence has wide applications in biosensing, chemical reaction detection, and medicine. Solid-state luminescent materials, due to their excellent photoluminescence quantum yield and photostability, have demonstrated remarkable capabilities in practical applications in optoelectronic devices, chemical sensing, and bioimaging. However, most luminescent material molecules exhibit strong π-π stacking, leading to aggregation-induced fluorescence quenching (AIQ). At low concentrations, molecules are independent and can emit fluorescence; as the concentration increases, aggregation or stacking occurs, affecting the molecular arrangement and causing a decrease in fluorescence intensity. In practice, most fluorescent materials are in solid or thin film form, making aggregation unavoidable. In 2001, Professor Tang Benzong's team discovered aggregation-induced emission (AIE), which is the opposite of AIE. At low concentrations, the fluorescence is weak or nonexistent, while at high concentrations, the fluorescence increases. This effectively solves the practical application problem of fluorescent materials. Tetraphenylene (TPE) is a typical molecule with the AIE effect. It has C2 symmetry and four reaction sites, and has excellent properties for constructing organic cage-like compounds.
[0004] Based on this, the present invention provides a method for designing and synthesizing a type of TPE framework molecular cage. Summary of the Invention
[0005] To address the problems existing in the prior art, this invention provides a method for synthesizing a class of TPE framework molecular cages. This method is simple and easy to implement, and the obtained TPE framework molecular cages exhibit AIE effect, high quantum yield, and higher photostability. Based on this series of molecular cages with AIE properties, new possibilities are provided for further exploration of biofluorescent probes.
[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:
[0007] A method for synthesizing a type of TPE framework molecular cage includes the following steps: Tetrar-R-tetraaldehyde-tetraphenylene and cyclohexanediamine are added to CHCl3 and heated under reflux with stirring to obtain a solid product, a tetrar-R-tetraphenylene molecular cage, where R = OH, OCH3, or OCH2CH3. The obtained tetrar-R-tetraphenylene molecular cage is washed and then dried in a vacuum oven to obtain yellow crystals, which are the TPE framework molecular cages. The reaction route is shown below:
[0008]
[0009] Furthermore, when R = OH, the molar ratio of tetrahydroxytetraaldehyde tetraphenylethylene to cyclohexanediamine is 1:2.
[0010] Furthermore, when R = OCH3, the molar ratio of tetramethoxytetraaldehyde tetraphenylethylene and cyclohexanediamine is 1:2.4.
[0011] Furthermore, when R = OCH2CH3, the molar ratio of tetraethoxytetraaldehyde tetrastyrene to cyclohexanediamine is 1:4.
[0012] Furthermore, in the steps described in this invention, the stirring temperature during the synthesis of the tetrahydroxytetraphenylene molecular cage is 55°C, and the reflux reaction time is 12 hours.
[0013] Furthermore, in the steps described in this invention, the stirring temperature during the synthesis of the tetramethoxytetraphenyl molecule cage is 55°C, and the reflux reaction time is 12 hours.
[0014] Furthermore, in the steps described in this invention, the stirring temperature during the synthesis of the tetraethoxytetraphenyl molecule cage is 65°C, and the reflux reaction time is 12 hours.
[0015] Furthermore, the solid product tetrar-based tetrastyrene molecular cage (R = OH, OCH3, OCH2CH3) of the present invention was washed three times with ethyl acetate and then five times with methanol.
[0016] Furthermore, the drying temperature described in this invention is room temperature, and the drying time is 24 hours.
[0017] The present invention also provides a TPE framework molecular cage prepared by the above synthesis method.
[0018] The beneficial effects of the present invention are as follows: The synthesis method of the TPE framework molecular cage provided by the present invention is simple and easy to implement. The obtained TPE framework molecular cage has the AIE effect, high quantum yield and higher photostability, and can be used as a fluorescent probe. Attached Figure Description
[0019] Figure 1This is a flowchart illustrating the preparation route of the TPE framework structure molecular cage material of the present invention.
[0020] Figure 2 The infrared absorption spectrum of the compound tetrahydroxytetraphenylene molecule dissolved in THF solvent.
[0021] Figure 3 The TGA thermogravimetric analysis diagram of the molecular cage of the compound tetrahydroxytetraphenylene is shown.
[0022] Figure 4 This is a specific surface area analysis diagram of the molecular cage of the compound tetrahydroxytetraphenylene.
[0023] Figure 5 The image shows the 1H NMR spectrum of the molecular cage of the compound tetrahydroxytetraphenylene.
[0024] Figure 6 The fluorescence emission intensity of the tetrahydroxytetraphenylene molecular cage in a mixture of H2O / THF (where the volume fraction of H2O ranges from 0% to 95%) is the change.
[0025] Figure 7 The infrared absorption spectrum of the compound tetramethoxytetraphenylene molecule cage dissolved in THF solvent is shown.
[0026] Figure 8 The TGA thermogravimetric analysis diagram of the molecular cage of the compound tetramethoxytetraphenylene is shown.
[0027] Figure 9 This is a specific surface area analysis diagram of the molecular cage of the compound tetramethoxytetraphenylene.
[0028] Figure 10 The image shows the 1H NMR spectrum of the molecular cage of the compound tetramethoxytetraphenylene.
[0029] Figure 11 The fluorescence emission intensity of the tetramethoxytetraphenylene molecular cage is shown as the change in fluorescence emission intensity of the compound in a mixture of H2O / THF (where the volume fraction of H2O ranges from 0% to 95%).
[0030] Figure 12 The image shows the infrared absorption spectrum of the tetraethoxytetraphenylene molecular cage dissolved in THF solvent.
[0031] Figure 13 The TGA thermogravimetric analysis diagram of the molecular cage of the compound tetraethoxytetraphenylene is shown.
[0032] Figure 14 This is a graph showing the specific surface area of the molecular cage of the compound tetraethoxytetraphenylene.
[0033] Figure 15 The image shows the 1H NMR spectrum of the molecular cage of the compound tetraethoxytetraphenylene.
[0034] Figure 16 The fluorescence emission intensity of the tetraethoxytetraphenylene molecular cage is shown as the change in fluorescence emission intensity of the compound in a mixture of H2O / THF (where the volume fraction of H2O ranges from 0% to 95%).
[0035] Figure 17 Images show samples of the tetrahydroxytetraphenyl styrene molecular cage compound with the TPE skeleton structure of this invention, wetted by different solvents (from left to right: no solvent, tetrahydrofuran, chloroform) under 365nm ultraviolet light irradiation.
[0036] Figure 18 Images show samples of the tetramethoxytetraphenylene molecular cage compound with the TPE framework structure of this invention, wetted by different solvents (from left to right: no solvent, tetrahydrofuran, chloroform) under 365nm ultraviolet light irradiation.
[0037] Figure 19 Images show samples of the tetraethoxytetraphenylene molecular cage compound with the TPE framework structure of this invention, wetted by different solvents (from left to right: no solvent, tetrahydrofuran, chloroform) under 365nm ultraviolet light irradiation.
[0038] Figure 20 The NMR spectrum of the assembled tetrahydroxytetraphenylene molecular cage is shown in 1H NMR.
[0039] Figure 21 The NMR spectrum of the assembled tetramethoxytetraphenylene molecular cage is shown in 1H NMR.
[0040] Figure 22 The NMR spectrum of the assembled tetraethoxytetraphenylene molecular cage is shown in 1H NMR. Detailed Implementation
[0041] The present invention will be further described below with reference to specific embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Those skilled in the art can make some non-essential improvements and adjustments based on the above-described invention.
[0042] Figure 1 This is a flowchart illustrating the preparation route of the TPE framework molecular cage of the present invention.
[0043] Example 1
[0044] The preparation method of the TPE framework molecular cage in this embodiment is as follows:
[0045] Tetrahydroxytetraaldehyde tetraphenylethylene (4.54 g, 8.93 mmol) and cyclohexanediamine (2.04 g, 17.86 mmol) were added to CHCl3 solution and refluxed under vigorous stirring at 55 °C for 12 hours. The solid product, tetrahydroxytetraphenylethylene molecular cages, was washed three times with ethyl acetate, then five times with methanol, and then dried in a vacuum oven at room temperature for 24 hours. The resulting yellow crystals were the TPE framework molecular cages. The reaction route is as follows: Figure 1 As shown.
[0046] Example 2
[0047] The preparation method of the TPE framework molecular cage in this embodiment is as follows:
[0048] Tetramethoxytetraaldehyde tetraphenylethylene (3.6 g, 6.38 mmol) and cyclohexanediamine (1.75 g, 15.31 mmol) were added to CHCl3 solution and refluxed under vigorous stirring at 55 °C for 12 hours. The solid product, tetramethoxytetraphenylethylene molecular cages, was washed three times with ethyl acetate, then five times with methanol, and then dried in a vacuum oven at room temperature for 24 hours. The resulting yellow crystals were the TPE framework molecular cages. The reaction route is as follows: Figure 1 As shown.
[0049] Example 3
[0050] The preparation method of the TPE framework molecular cage in this embodiment is as follows:
[0051] Tetraethoxytetraaldehyde tetraphenylethylene (8.4 g, 13.46 mmol) and cyclohexanediamine (6.15 g, 53.84 mmol) were added to CHCl3 solution and refluxed under vigorous stirring at 65 °C for 12 hours. The solid product, tetraethoxytetraphenylethylene molecular cages, was washed three times with ethyl acetate, then five times with methanol, and then dried in a vacuum oven for 24 hours. The resulting yellow crystals were the TPE framework molecular cages. The reaction route is as follows: Figure 1 As shown.
[0052] Figure 2 The image shows the infrared absorption spectrum of the compound tetrahydroxytetraphenylene molecule dissolved in THF solvent. The infrared absorption curve is located at 3438.51 cm⁻¹. -1 There is a sharp and narrow strong peak at 152.89 cm⁻¹, which is the characteristic peak of -OH; -1 1488.68cm -1 and 1447.69cm -1 There are peaks of varying intensity at this point, which are characteristic peaks generated by the bending vibration of the aromatic ring.
[0053] Figure 3The TGA thermogravimetric analysis of the tetrahydroxytetraphenylene molecular cage shows that the structure of the substance is relatively stable at 0-150℃; at 150-200℃, the substance begins to decompose slightly; at 300-400℃, it continues to decompose slightly; and at 400-800℃, the substance collapses significantly, and after complete carbonization, it no longer loses weight, retaining 45% of its initial weight.
[0054] Figure 4 The graph shows the specific surface area of the tetrahydroxytetraphenylene molecular cage, indicating a specific surface area of 28.27 m². 2 / g, with an adsorption-desorption value of 27.03, and the pore size distribution curve indicates the presence of pores in the material.
[0055] Figure 5 The image shows the 1H NMR spectrum of the compound tetrahydroxytetraphenylene. It can be seen that the hydrogen base peak is correct, the classification is correct, and the integration is correct, which allows us to identify the target product.
[0056] Figure 6 The fluorescence emission intensity of the tetrahydroxytetraphenylene molecular cage is represented by the change in fluorescence emission intensity in a mixture of H2O / THF from 0% to 95%, which is the luminescence of the molecule in different aggregation and dissolution states.
[0057] Figure 7 The image shows the infrared absorption spectrum of the compound tetramethoxytetraphenylene molecule dissolved in THF solvent. The infrared absorption curve is located at 1458.90 cm⁻¹. -1 and 1384.00cm -1 There are two sharp and narrow vibrational peaks, which are characteristic peaks of -OCH3; at 1602.71 cm⁻¹. -1 1492.88cm -1 and 1458.90cm -1 There are aromatic ring skeletal vibration peaks of varying intensities at 1260.90 cm⁻¹. -1 and 1026.62cm -1 The two peaks with antisymmetric and symmetric stretching vibrations are characteristic peaks of the presence of COC.
[0058] Figure 8 The TGA thermogravimetric analysis (TGA) curve of the tetramethoxytetraphenylene molecular cage shows that the structure of the material is relatively stable before 337℃; between 337-550℃, the material begins to collapse for the first time, and then the structure tends to stabilize again; at around 1000℃, the structure of the material completely collapses and tends to be completely carbonized.
[0059] Figure 9 The graph shows the specific surface area of the tetramethoxytetraphenylene molecular cage, indicating a specific surface area of 42.38 m². 2 / g, with an adsorption-desorption value of 21.47, and the pore size distribution curve indicates the presence of pores in the material.
[0060] Figure 10 The image shows the 1H NMR spectrum of the compound tetramethoxytetraphenylene. It can be seen that the hydrogen base peak is correct, the classification is correct, and the integration is correct, which allows us to identify the target product.
[0061] Figure 11 The fluorescence emission intensity of the tetramethoxytetraphenylene molecular cage is represented by the change in fluorescence emission intensity of the compound in a mixture of H2O / THF from 0% to 95%, which is the luminescence of the molecule in different aggregation and dissolution states.
[0062] Figure 12 The image shows the infrared absorption spectrum of the tetraethoxytetraphenylene molecular cage dissolved in THF solvent. The infrared absorption curve is located at 1385.98 cm⁻¹. -1 The presence of a pair of vibrational peaks indicating symmetrical deformation of methyl groups confirms the presence of -OCH2CH3; 2977.80 cm⁻¹ -1 and 2926.20cm -1 The two peaks are characteristic of methyl and methylene, respectively; at 1601.30 cm⁻¹. -1 1494.03cm -1 and 1447.96cm -1 There are aromatic ring skeleton vibration peaks of varying intensities.
[0063] Figure 13 The TGA thermogravimetric analysis of the tetraethoxytetraphenylene molecular cage shows that the structure of the substance is relatively stable before 325℃; the structure begins to collapse between 325-580℃, and then tends to stabilize again, with a weight loss rate of 69.6%. Subsequently, carbon combustion leads to a small amount of weight loss, but the overall structure tends to stabilize.
[0064] Figure 14 The graph shows the specific surface area of the tetraethoxytetraphenylene molecular cage, indicating a specific surface area of 60.26 m². 2 / g, adsorption-desorption value is 45.97, and pore size distribution curve indicates the presence of pores in the material.
[0065] Figure 15 The image shows the 1H NMR spectrum of the compound tetraethoxytetraphenylene. It can be seen that the hydrogen base peak is correct, the classification is correct, and the integration is correct, which allows us to identify the target product.
[0066] Figure 16 The fluorescence emission intensity of the tetraethoxytetraphenylene molecular cage is represented by the change in fluorescence emission intensity of the compound tetraethoxytetraphenylene in a mixture of H2O / THF from 0% to 95%, which is the luminescence of the molecule in different aggregation and dissolution states.
[0067] Figure 17 These are images of samples of the tetrahydroxytetraphenylene molecular cage compound with the TPE skeleton structure of this invention, wetted by different solvents (from left to right: no solvent, tetrahydrofuran, chloroform) under 365nm ultraviolet light irradiation. The images allow for color differentiation of different solvents.
[0068] Figure 18 These are images of samples of the tetramethoxytetraphenylene molecular cage compound with the TPE skeleton structure of this invention, wetted by different solvents (from left to right: no solvent, tetrahydrofuran, chloroform) under 365nm ultraviolet light irradiation. The images allow for color differentiation of different solvents.
[0069] Figure 19 These are images of samples of the tetraethoxytetraphenylene molecular cage compound with the TPE skeleton structure of this invention, wetted by different solvents (from left to right: no solvent, tetrahydrofuran, chloroform) under 365nm ultraviolet light irradiation. The images allow for color differentiation of different solvents.
[0070] Figure 20 The image shows the 1H NMR spectrum of the tetrahydroxytetraphenylene molecular cage assembly, indicating that the reactants reacted completely and the molecular cage was assembled.
[0071] Figure 21 The image shows the 1H NMR spectrum of the tetramethoxytetraphenylene molecular cage assembly, indicating that the reactants reacted completely and the molecular cage was assembled.
[0072] Figure 22 The image shows the 1H NMR spectrum of the tetraethoxytetraphenylene molecular cage assembly, indicating that the reactants reacted completely and the molecular cage was assembled.
[0073] The foregoing has shown and described the basic principles and main features of the present invention, as well as its advantages. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.
Claims
1. A method for synthesizing a class of TPE framework molecular cages, characterized in that: Tetrarro-tetraaldehyde-tetraphenylene and cyclohexanediamine were added to CHCl3 and heated under reflux with stirring to obtain a solid product, tetrarro-tetraphenylene molecular cage, where R = OH, OCH3, or OCH2CH3. The obtained tetrarro-tetraphenylene molecular cage was washed and then dried in a vacuum oven to obtain yellow crystals, which are the TPE framework molecular cages. The structural formula of tetrarro-tetraaldehyde-tetraphenylene is as follows: ； The structural formula of cyclohexanediamine is as follows: ； When R=OH, the stirring temperature for the synthesis of tetrahydroxytetraaldehyde tetraphenylethylene molecular cage is 55℃, and the reflux reaction time is 12 hours. When R=OCH3, the stirring temperature for the synthesis of tetramethoxytetraphenylene molecular cages is 55℃ and the reflux reaction time is 12 hours. When R=OCH2CH3, the stirring temperature for the synthesis of tetraethoxytetraphenylene molecular cages is 65℃ and the reflux reaction time is 12 hours. When R=OH, the molar ratio of tetrahydroxytetraaldehyde tetraphenylethylene and cyclohexanediamine is 1:2; When R = OCH3, the molar ratio of tetramethoxytetraaldehyde tetraphenylethylene to cyclohexanediamine is 1:2.4; when R = OCH2CH3, the molar ratio of tetraethoxytetraaldehyde tetraphenylethylene to cyclohexanediamine is 1:
4.
2. The method for synthesizing a type of TPE framework molecular cage according to claim 1, characterized in that: The solid product, tetrar-based tetrastyrene molecular cage, was washed three times with ethyl acetate and then five times with methanol.
3. The method for synthesizing a type of TPE framework molecular cage according to claim 1, characterized in that: The drying temperature is room temperature, and the drying time is 24 hours.
4. The TPE framework molecular cage prepared by the synthesis method according to any one of claims 1-3.