Process for the preparation of o-alkynyl aniline compounds having aggregation-induced emission properties

Abstract

The application belongs to the technical field of preparation of o-alkynyl aniline compounds, and particularly relates to a preparation method of an o-alkynyl aniline compound with an aggregation-induced emission property. The preparation method comprises the following steps: (1) under the catalysis of bis-triphenylphosphine palladium dichloride and cuprous iodide, 1,2-bis(4-bromophenyl)-1,2-stilbene is reacted with trimethylsilyl acetylene to prepare an intermediate crude product, and then the intermediate crude product is subjected to a trimethylsilyl group removal reaction to prepare 1,2-bis(4-ethynylphenyl)-1,2-diphenyl ethylene; (2) under the catalysis of bis-triphenylphosphine palladium dichloride and cuprous iodide, 1,2-bis(4-ethynylphenyl)-1,2-diphenyl ethylene is reacted with 2-iodoaniline to prepare an o-alkynyl aniline compound. The o-alkynyl aniline compound prepared by the application has a good aggregation-induced emission property.

Description

Preparation method of o-alkynyl aniline compounds with aggregation-induced emission properties Technical Field

[0001] This invention belongs to the field of preparation technology of o-alkynylaniline compounds, specifically relating to a method for preparing o-alkynylaniline compounds with aggregation-induced emission properties. Background Technology

[0002] Fluorescent materials, due to their tunable photophysical properties, have wide applications in biomedical imaging, environmental monitoring, and organic light-emitting diodes (OLEDs), making them a hot topic in functional materials research. Traditional fluorescent materials suffer from aggregation-induced quenching (ACQ)—where, in dilute solutions, due to molecular dispersion, excited-state energy is efficiently converted into fluorescence via radiative transitions, resulting in strong luminescence. However, upon entering the aggregated state, the intermolecular distance shortens, easily inducing π-π stacking, charge transfer, and exciton annihilation. Excited-state energy is significantly lost through non-radiative dissipation, leading to a sharp drop in fluorescence intensity or even quenching. The ACQ effect severely limits their industrial application in solid-state optoelectronic devices and high-sensitivity detection.

[0003] In 2001, Academician Tang Benzhong's team (Luo J, Xie Z, Lam JWY, et al. Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole[J]. Chemical Communications, 2001, (18): 1740-1741.) discovered that 1-methyl-1,2,3,4,5-pentaphenylsilane exhibits aggregation-induced emission (AIE). In solution, intramolecular groups (such as the benzene ring) can rotate and vibrate freely, resulting in non-radiative dissipation of excited-state energy and almost no emission. However, in the aggregated state, intermolecular interactions restrict intramolecular motion (RIM), suppressing non-radiative dissipation, and releasing more excited-state energy through radiative transitions, achieving strong emission. This provides a new approach for the design of high quantum yield solid-state luminescent materials. In recent years, a variety of compounds with AIE effect have been developed. Among them, tetraphenylethylene (TPE) has become the core building block of AIE materials due to its advantages such as simple synthesis, tunable structure, significant AIE properties, and ease of functionalization. It is widely used to construct a variety of AIE functional materials.

[0004] Although numerous AIE materials based on TPE structural units have been reported, most of the reported TPE derivatives contain only one active functional group (such as halogen, carboxyl, hydroxyl, etc.), limiting their functionalization pathways and making it difficult to meet the multifunctional integration requirements of complex scenarios. Designing and developing novel TPE-based compounds that combine AIE effects with multiple reaction sites through simple and mature synthetic routes is of significant research importance and a key direction for promoting the development of AIE materials towards high performance and multifunctionality. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems of single functionalization pathways and complex preparation processes of AIE compounds based on TPE structural units, and to provide a method for preparing o-alkynyl aniline compounds with aggregation-induced emission properties. This preparation method achieves synergistic regulation of AIE performance and multifunctionality through dual active site design, and features mild reaction conditions and simple operation.

[0006] The method for preparing the o-alkynyl aniline compound with aggregation-induced emission properties according to the present invention comprises the following steps:

[0007] (1) 1,2-bis(4-bromophenyl)-1,2-diphenylphenyl, bis(triphenylphosphine)-palladium dichloride and cuprous iodide were added to a reaction vessel. Solvent was added to the reaction system under a nitrogen atmosphere. Then trimethylsilylacetylene was added dropwise. The temperature was raised to 60-80℃ and the reaction was carried out for 8-14 h. After the reaction was completed, the intermediate crude product was obtained by the first post-treatment. The intermediate crude product was dissolved in tetrahydrofuran to obtain the first mixture. KOH was dissolved in methanol to obtain the second mixture. Then the first mixture and the second mixture were stirred and mixed at room temperature. After the reaction was completed, the second post-treatment was carried out to prepare 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene.

[0008] (2) The 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene, 2-iodoaniline, bis(triphenylphosphine)palladium dichloride and cuprous iodide obtained in step (1) are added to the reaction vessel, the solvent is added under a nitrogen atmosphere, the temperature is raised to 60-80℃ and the reaction is carried out for 8-18 hours. After the reaction is completed, the o-ynylaniline compounds are prepared by post-treatment.

[0009] In step (1), bis(PPh3)2Cl2 and cuprous iodide (CuI) are used as catalysts. The molar amount of bis(PPh3)2Cl2 is 4% or 8% of the molar amount of 1,2-bis(4-bromophenyl)-1,2-diphenylphenyl, and the molar amount of cuprous iodide is 16% of the molar amount of 1,2-bis(4-bromophenyl)-1,2-diphenylphenyl.

[0010] In step (1), the molar ratio of trimethylsilylacetylene to 1,2-bis(4-bromophenyl)-1,2-diphenylene is 2-3:1.

[0011] The solvent mentioned in step (1) is a mixture of tetrahydrofuran and triethylamine, wherein the volume ratio of tetrahydrofuran to triethylamine is 1:4.

[0012] The first post-treatment described in step (1) is to wash the product with saturated brine after the reaction, separate the solution into layers, dry the collected organic phase, and then evaporate it under reduced pressure to obtain the intermediate crude product. The drying temperature is room temperature, the drying time is 12 h, the reduced pressure drying temperature is 45 °C, the reduced pressure drying vacuum degree is -0.09 MPa, the rotation speed during reduced pressure drying is 100 r / min, and the reduced pressure drying time is 1 h.

[0013] In step (1), the mass-to-volume ratio of the intermediate crude product to tetrahydrofuran in the first mixture is 4.36-4.62:41.5-44, in g / mL.

[0014] In step (1), the mass-volume ratio of KOH to methanol in the second mixture is 4.66-4.94 : 31-33, in g / mL.

[0015] In step (1), the mass ratio of the intermediate crude product in the first mixture to the KOH in the second mixture is 4.36-4.62: 4.66-4.94.

[0016] The stirring reaction time in step (1) is 12 hours.

[0017] The second post-treatment described in step (1) involves washing with saturated brine after the reaction, separating the solution into layers, drying the collected organic phase, and then purifying it by vacuum rotary evaporation and column chromatography to obtain 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene. The drying temperature was room temperature, the drying time was 12 h, the vacuum rotary evaporation temperature was 45 °C, the vacuum degree of vacuum rotary evaporation was -0.09 MPa, the rotation speed during vacuum rotary evaporation was 100 r / min, and the vacuum rotary evaporation time was 1 h.

[0018] The chemical reaction equations involved in step (1) are as follows:

[0019]

[0020] In step (2), the molar ratio of 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene to 2-iodoaniline is 1:2-3.

[0021] In step (2), palladium dichloride of bis(triphenylphosphine) is used as a catalyst, and the molar amount of palladium dichloride of bis(triphenylphosphine) is 2%-6% of the molar amount of 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene.

[0022] In step (2), cuprous iodide is used as a catalyst, and the molar amount of cuprous iodide accounts for 2%-10% of the molar amount of 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene.

[0023] The solvent in step (2) is a mixture of tetrahydrofuran and triethylamine, wherein the volume ratio of tetrahydrofuran to triethylamine is 3:2.

[0024] The post-treatment described in step (2) involves washing with saturated brine after the reaction, separating the solution into layers, drying the collected organic phase, and then purifying it by vacuum rotary evaporation and column chromatography to obtain o-alkynyl aniline compounds. The drying temperature is room temperature, the drying time is 12 h, the vacuum rotary evaporation temperature is 45 °C, the vacuum degree of vacuum rotary evaporation is -0.09 MPa, the rotation speed during vacuum rotary evaporation is 100 r / min, and the vacuum rotary evaporation time is 1 h.

[0025] The chemical reaction equation involved in step (2) is as follows:

[0026]

[0027] The structural formula of the o-alkynyl aniline compound prepared in step (2) is as follows:

[0028] .

[0029] The o-alkynyl aniline compounds prepared in step (2) exhibited good aggregation-induced emission properties in a mixed solution of water and tetrahydrofuran at a volume ratio of 9:1 and on a silica gel plate.

[0030] Compared with the prior art, the present invention has the following advantages:

[0031] (1) The method for preparing the o-alkynyl aniline compound with aggregation-induced emission properties according to the present invention uses 1,2-bis(4-bromophenyl)-1,2-diphenylphenyl and trimethylethynylsilane as raw materials, and carries out a Sonogashira coupling reaction under the catalysis of bis(triphenylphosphine) palladium dichloride and iodide ketone, followed by a detrimethylsilylation reaction to obtain 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene; then 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene and 2-iodoaniline carry out a Sonogashira coupling reaction under the catalysis of bis(triphenylphosphine) palladium dichloride and iodide ketone to obtain the o-alkynyl aniline compound. The first step of “protected alkyne” design works synergistically with “deprotection activation”. The protecting group ensures that the alkyne does not undergo side reactions after the first coupling step, and it immediately becomes reactive after deprotection, providing a precise site for the second coupling step. The two Sonogashira coupling steps share the same catalyst (bis(triphenylphosphine)-palladium dichloride + iodide-ketone), avoiding reaction compatibility issues caused by changing the catalyst system and improving synthesis efficiency.

[0032] (2) The method for preparing o-alkynyl aniline compounds with aggregation-induced emission properties described in this invention introduces alkynyl and amino dual active groups into TPE molecules. The alkynyl group can be rapidly coupled through CuAAC click chemistry and thiol-yne reaction, and the amino group can be constructed into a conjugated system through acylation and Buchwald-Hartwig amination. The functionalization pathway is significantly better than that of traditional TPE derivatives.

[0033] (3) The o-alkynyl aniline compounds prepared by the preparation method described in this invention exhibit a 66-fold increase in fluorescence intensity in aggregated state in a mixed solution of water and tetrahydrofuran at a volume ratio of 9:1 compared to fluorescence intensity in pure THF solution, demonstrating a good aggregation-induced emission effect.

[0034] (4) The method for preparing the o-alkynyl aniline compounds with aggregation-induced emission properties described in this invention is based on the Sonogashira coupling reaction with optimized catalyst ratio, reaction temperature ≤80℃, mild conditions, and yield of key intermediate greater than 80%.

[0035] (5) The o-alkynyl aniline compounds prepared by the preparation method described in this invention are a new type of AIE luminescent material with a wide range of applications. They have potential applications in the fields of luminescent intermediates and polymer functional material design, early damage indication and protection of concrete. Attached Figure Description

[0036] Figure 1 is the 1H NMR spectrum of the o-alkynyl aniline compound prepared in Example 1 of the present invention;

[0037] Figure 2 is the infrared spectrum of the o-alkynyl aniline compound prepared in Example 1 of the present invention;

[0038] Figure 3 shows the ultraviolet absorption spectrum of the o-alkynyl aniline compound prepared in Example 1 of the present invention;

[0039] Figure 4 shows the aggregation-induced luminescence properties of the o-alkynyl aniline compounds prepared in Example 1 of the present invention at different water / tetrahydrofuran ratios;

[0040] Figure 5 shows the aggregation-induced emission properties of the o-alkynyl aniline compounds prepared in Example 1 of the present invention on a silica gel plate as the solvent evaporates;

[0041] Figure 6 is a microscope photograph of the fiber coating prepared by blending the o-alkynyl aniline compound prepared in Example 1 of the present invention with polyacrylonitrile material. Detailed Implementation

[0042] Example 1

[0043] The preparation method of the o-alkynyl aniline compound with aggregation-induced emission properties described in Example 1 consists of the following steps:

[0044] (1) 1,2-Di(4-bromophenyl)-1,2-diphenylene (4.90 g, 10 mmol), Pd(PPh3)2Cl2 catalyst (0.56 g, 0.8 mmol), and CuI catalyst (0.305 g, 1.6 mmol) were added to a two-necked flask. After evacuating the flask three times with nitrogen, 10 mL of tetrahydrofuran and 40 mL of triethylamine solvent were added under a nitrogen atmosphere, followed by the slow addition of trimethylsilylacetylene (2.455 g, 25 mmol). The temperature was raised to 80 °C and the reaction was carried out for 12 h. After the reaction was completed, the flask was washed with saturated brine, the solution was separated into layers, and the collected organic phase was dried and then evaporated under reduced pressure (drying temperature was room temperature, drying time was 12 h, reduced pressure evaporation temperature was 45 °C, reduced pressure evaporation vacuum degree was -0.09 MPa, the rotation speed was 100 r / min, and the reduced pressure evaporation time was 1 h), yielding 4.62 g of intermediate crude product. The crude product was dissolved in 44 mL of tetrahydrofuran to obtain a first mixture. KOH (4.94 g, 88 mmol) was dissolved in 33 mL of methanol to obtain a second mixture. The first and second mixtures were then combined and placed in a single-necked round-bottom flask containing a magnetic stir bar, and the mixture was stirred at room temperature for 12 h. After the reaction was complete, the mixture was washed with saturated brine, and the solutions separated into layers. The collected organic phase was dried and then evaporated under reduced pressure (drying temperature: room temperature; drying time: 12 h; reduced pressure evaporation temperature: 45 °C; reduced pressure evaporation vacuum: -0.09 MPa; rotation speed: 100 r / min; reduced pressure evaporation time: 1 h). Column chromatography was used to separate and purify the solid, yielding 3.287 g of a white solid, namely 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene, with a yield of 86.4%.

[0045] (2) The 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene (5 mmol, 1.90 g), 2-iodoaniline (13 mmol, 2.85 g), Pd(PPh3)2Cl2 (0.25 mmol, 0.18 g), and CuI (0.4 mmol, 0.076 g) obtained in step (1) were added to a two-necked flask. After evacuating the flask and purging it with nitrogen three times, 30 mL of tetrahydrofuran and 20 mL of triethylamine solvent were added under a nitrogen atmosphere. The mixture was then slowly heated to 80 °C at room temperature and reacted for 10 h. After the reaction was complete, the solution was washed with saturated brine, separated into layers, and the collected organic phase was dried and then evaporated under reduced pressure (drying temperature: room temperature, drying time: 12 h, reduced pressure drying temperature: 45 °C, reduced pressure vacuum: -0.09 MPa, rotation speed: 100 r / min, reduced pressure drying time: 1 h). Column chromatography was used to separate and purify the solution, yielding 2.372 g of a yellow solid, which was an o-alkynylaniline compound, with a yield of 84.3%. High-performance liquid chromatography (HPLC) analysis (conditions: C18 column, acetonitrile / water mobile phase, flow rate: 1.0 mL / min; area normalization method) showed a purity of 94.5%.

[0046] The structural formula of the o-alkynyl aniline compound prepared in Example 1 is as follows: .

[0047] Analysis revealed that the 1H NMR spectrum of this o-ynylaniline compound is shown in Figure 1. Chemical shifts of 5.49 ppm and 5.77 ppm correspond to four hydrogen atoms at the amino position on the benzene ring, while chemical shifts in the range of 6.35–7.92 ppm correspond to 26 hydrogen atoms on the benzene ring. The infrared spectrum of this o-ynylaniline compound is shown in Figure 2, with wavelengths of 1455, 1488, and 1614 cm⁻¹. -1 The peaks are characteristic stretching vibration peaks of the benzene ring, at 3353 and 3462 cm⁻¹. -1 Two relatively broad absorption peaks were observed at 2205 cm⁻¹, confirming the presence of amino groups in the product. -1The peaks at the specified locations correspond to the alkynyl functional groups in the product, confirming the correct structure of the o-alkynyl aniline compound. The UV absorption spectrum of this o-alkynyl aniline compound is shown in Figure 3, with absorption peaks at 240 nm and 365 nm. The aggregation-induced emission (AIE) properties of this o-alkynyl aniline compound under different water / tetrahydrofuran ratios are shown in Figure 4. As the water content in the solution increases, the fluorescence emission intensity gradually increases. The fluorescence intensity reaches its maximum in a mixed solution with a water-to-tetrahydrofuran volume ratio of 9:1 (i.e., 90% water content), exhibiting a significant AIE effect. The aggregation-induced emission properties of this o-alkynyl aniline compound on a silica gel plate as the solvent evaporates are shown in Figure 5. As can be seen from the figure, with increasing time, the solvent gradually evaporates, the product gradually aggregates, leading to a gradual increase in fluorescence intensity. At 15 seconds, the dots begin to brighten from the edges; after 35 seconds, the solvent completely evaporates, and the dots become entirely bright, exhibiting the strongest emission. Figures 4 and 5 reflect the aggregation-induced emission phenomenon of this product. This o-alkynyl aniline compound has solid-state luminescence properties. It is mixed with polyacrylonitrile at a mass ratio of 3:2 and dissolved in tetrahydrofuran to prepare a 2 mg / mL mixed solution. The solution is then electrospun into a fiber coating (Figure 6) and attached to key parts of concrete (such as beam and column joints). When micro-cracks or stress concentrations that are not visible to the naked eye occur, AIE fluorescence enhancement is triggered, thereby enabling damage prediction before macroscopic failure of key parts of concrete.

[0048] Example 2

[0049] The preparation method of the o-alkynyl aniline compound with aggregation-induced emission properties described in Example 2 consists of the following steps:

[0050] (1) 1,2-Di(4-bromophenyl)-1,2-diphenylene (4.90 g, 10 mmol), Pd(PPh3)2Cl2 catalyst (0.28 g, 0.4 mmol), and CuI catalyst (0.305 g, 1.6 mmol) were added to a two-necked flask. After evacuating the flask three times with nitrogen, 10 mL of tetrahydrofuran and 40 mL of triethylamine solvent were added under a nitrogen atmosphere, followed by the slow addition of trimethylsilylacetylene (1.965 g, 20 mmol). The mixture was heated to 60 °C and reacted for 8 h. After the reaction was completed, the mixture was washed with saturated brine, and the solution was separated into layers. The collected organic phase was dried and then evaporated under reduced pressure (drying temperature was room temperature, drying time was 12 h, the temperature during evaporation was 45 °C, the vacuum degree during evaporation was -0.09 MPa, the rotation speed during evaporation was 100 r / min, and the evaporation time was 1 h), yielding 4.36 g of the intermediate crude product. The crude product was dissolved in 41.5 mL of tetrahydrofuran to obtain a first mixture, and KOH (4.66 g, 83 mmol) was dissolved in 31 mL of methanol to obtain a second mixture. The first and second mixtures were then combined and placed in a single-necked round-bottom flask containing a magnetic stir bar, and the mixture was stirred at room temperature for 12 h. After the reaction was complete, the mixture was washed with saturated brine, and the solutions separated into layers. The collected organic phase was dried and then evaporated under reduced pressure (drying temperature: room temperature; drying time: 12 h; temperature during evaporation under reduced pressure: 45 °C; vacuum degree: -0.09 MPa; rotation speed: 100 r / min; time: 1 h). Column chromatography was used to separate and purify the solid, yielding 3.093 g of a white solid, 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene, with a yield of 81.3%.

[0051] (2) The 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene (5 mmol, 1.90 g), 2-iodoaniline (10 mmol, 2.19 g), Pd(PPh3)2Cl2 (0.1 mmol, 0.07 g), and CuI (0.1 mmol, 0.019 g) obtained in step (1) were added to a two-necked flask. After evacuating the flask and purging it with nitrogen three times, 30 mL of tetrahydrofuran and 20 mL of triethylamine solvent were added under a nitrogen atmosphere. The mixture was then slowly heated to 60 °C at room temperature and reacted for 8 h. After the reaction was completed, the solution was washed with saturated brine, separated into layers, and the collected organic phase was dried and then evaporated under reduced pressure (drying temperature: room temperature, drying time: 12 h, temperature during evaporation under reduced pressure: 45 °C, vacuum degree: -0.09 MPa, rotation speed during evaporation under reduced pressure: 100 r / min, evaporation time: 1 h). Column chromatography was used to separate and purify the solution, yielding 2.009 g of a yellow solid, which was an o-alkynyl aniline compound, with a yield of 71.4%. High-performance liquid chromatography (HPLC) analysis (conditions: C18 column, acetonitrile / water mobile phase, flow rate: 1.0 mL / min; area normalization method) showed a purity of 92.8%.

[0052] The structural formula of the o-alkynyl aniline compound prepared in Example 2 is as follows: .

[0053] Example 3

[0054] The preparation method of the o-alkynyl aniline compound with aggregation-induced emission properties described in Example 3 consists of the following steps:

[0055] (1) 1,2-Di(4-bromophenyl)-1,2-diphenylene (4.90 g, 10 mmol), Pd(PPh3)2Cl2 catalyst (0.56 g, 0.8 mmol), and CuI catalyst (0.305 g, 1.6 mmol) were added to a two-necked flask. After evacuating the flask three times with nitrogen, 10 mL of tetrahydrofuran and 40 mL of triethylamine solvent were added under a nitrogen atmosphere, followed by the slow addition of trimethylsilylacetylene (2.455 g, 25 mmol). The temperature was raised to 70 °C and the reaction was carried out for 14 h. After the reaction was completed, the flask was washed with saturated brine, the solution was separated into layers, and the collected organic phase was dried and then evaporated under reduced pressure (drying temperature was room temperature, drying time was 12 h, the temperature during evaporation was 45 °C, the vacuum degree during evaporation was -0.09 MPa, the rotation speed during evaporation was 100 r / min, and the evaporation time was 1 h), yielding 4.46 g of intermediate crude product. The crude product was dissolved in 42.5 mL of tetrahydrofuran to obtain a first mixture, and KOH (4.77 g, 85 mmol) was dissolved in 32 mL of methanol to obtain a second mixture. The first and second mixtures were then combined and placed in a single-necked round-bottom flask containing a magnetic stir bar, and the mixture was stirred at room temperature for 12 h. After the reaction was complete, the mixture was washed with saturated brine, and the solutions separated into layers. The collected organic phase was dried and then evaporated under reduced pressure (drying temperature: room temperature; drying time: 12 h; temperature during evaporation: 45 °C; vacuum degree: -0.09 MPa; rotation speed: 100 r / min; time: 1 h). Column chromatography was used to separate and purify the solid, yielding 3.185 g of a white solid, 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene, with a yield of 83.7%.

[0056] (2) The 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene (5 mmol, 1.90 g), 2-iodoaniline (12.5 mmol, 2.74 g), Pd(PPh3)2Cl2 (0.1 mmol, 0.07 g), and CuI (0.2 mmol, 0.038 g) obtained in step (1) were added to a two-necked flask. After evacuating the flask and purging it with nitrogen three times, 30 mL of tetrahydrofuran and 20 mL of triethylamine solvent were added under a nitrogen atmosphere. The mixture was then slowly heated from room temperature to 70 °C and reacted for 10 h. After the reaction was completed, the solution was washed with saturated brine, separated into layers, and the collected organic phase was dried and then evaporated under reduced pressure (drying temperature: room temperature, drying time: 12 h, temperature during evaporation under reduced pressure: 45 °C, vacuum degree: -0.09 MPa, rotation speed during evaporation under reduced pressure: 100 r / min, evaporation time: 1 h). Column chromatography was used to separate and purify the solution, yielding 2.254 g of a yellow solid, which was an o-alkynyl aniline compound, with a yield of 80.1%. High-performance liquid chromatography (HPLC) analysis (conditions: C18 column, acetonitrile / water mobile phase, flow rate: 1.0 mL / min; area normalization method) showed a purity of 93.1%.

[0057] The structural formula of the o-alkynyl aniline compound prepared in Example 3 is as follows: .

[0058] Example 4

[0059] The preparation method of the o-alkynyl aniline compound with aggregation-induced emission properties described in Example 4 consists of the following steps:

[0060] (1) 1,2-Di(4-bromophenyl)-1,2-diphenylene (4.90 g, 10 mmol), Pd(PPh3)2Cl2 catalyst (0.56 g, 0.8 mmol), and CuI catalyst (0.305 g, 1.6 mmol) were added to a two-necked flask. After evacuating the flask three times with nitrogen, 10 mL of tetrahydrofuran and 40 mL of triethylamine solvent were added under a nitrogen atmosphere, followed by the slow addition of trimethylsilylacetylene (2.945 g, 30 mmol). The temperature was raised to 80 °C and the reaction was carried out for 10 h. After the reaction was completed, the flask was washed with saturated brine, the solution was separated into layers, and the collected organic phase was dried and then evaporated under reduced pressure (drying temperature was room temperature, drying time was 12 h, the temperature during evaporation was 45 °C, the vacuum degree during evaporation was -0.09 MPa, the rotation speed during evaporation was 100 r / min, and the evaporation time was 1 h), yielding 4.57 g of intermediate crude product. The crude product was dissolved in 43.5 mL of tetrahydrofuran to obtain a first mixture, and KOH (4.89 g, 87 mmol) was dissolved in 33 mL of methanol to obtain a second mixture. The first and second mixtures were then combined and placed in a single-necked round-bottom flask containing a magnetic stir bar, and the mixture was stirred at room temperature for 12 h. After the reaction was complete, the mixture was washed with saturated brine, and the solutions separated into layers. The collected organic phase was dried and then evaporated under reduced pressure (drying temperature: room temperature; drying time: 12 h; temperature during evaporation under reduced pressure: 45 °C; vacuum degree: -0.09 MPa; rotation speed: 100 r / min; time: 1 h). Column chromatography was used to separate and purify the solid, yielding 3.238 g of a white solid, 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene, with a yield of 85.1%.

[0061] (2) The 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene (5 mmol, 1.90 g), 2-iodoaniline (13 mmol, 2.85 g), Pd(PPh3)2Cl2 (0.2 mmol, 0.14 g), and CuI (0.3 mmol, 0.057 g) obtained in step (1) were added to a two-necked flask. After evacuating the flask and purging it with nitrogen three times, 30 mL of tetrahydrofuran and 20 mL of triethylamine solvent were added under a nitrogen atmosphere. The mixture was then slowly heated to 80 °C at room temperature and reacted for 12 h. After the reaction was completed, the solution was washed with saturated brine, separated into layers, and the collected organic phase was dried and then evaporated under reduced pressure (drying temperature: room temperature, drying time: 12 h, temperature during evaporation under reduced pressure: 45 °C, vacuum degree: -0.09 MPa, rotation speed during evaporation under reduced pressure: 100 r / min, evaporation time: 1 h). Column chromatography was used to separate and purify the solution, yielding 2.285 g of a yellow solid, which was an o-alkynyl aniline compound, with a yield of 81.2%. High-performance liquid chromatography (HPLC) analysis (conditions: C18 column, acetonitrile / water mobile phase, flow rate: 1.0 mL / min; area normalization method) showed a purity of 94.2%.

[0062] The structural formula of the o-alkynyl aniline compound prepared in Example 4 is as follows: .

[0063] Example 5

[0064] The preparation method of the o-alkynyl aniline compound with aggregation-induced emission properties described in Example 5 consists of the following steps:

[0065] (1) 1,2-Di(4-bromophenyl)-1,2-diphenylene (4.90 g, 10 mmol), Pd(PPh3)2Cl2 catalyst (0.56 g, 0.8 mmol), and CuI catalyst (0.305 g, 1.6 mmol) were added to a two-necked flask. After evacuating the flask three times with nitrogen, 10 mL of tetrahydrofuran and 40 mL of triethylamine solvent were added under a nitrogen atmosphere, followed by the slow addition of trimethylsilylacetylene (2.455 g, 25 mmol). The temperature was raised to 80 °C and the reaction was carried out for 12 h. After the reaction was completed, the flask was washed with saturated brine, the solution was separated into layers, and the collected organic phase was dried and then evaporated under reduced pressure (drying temperature was room temperature, drying time was 12 h, the temperature during evaporation was 45 °C, the vacuum degree during evaporation was -0.09 MPa, the rotation speed during evaporation was 100 r / min, and the evaporation time was 1 h), yielding 4.62 g of intermediate crude product. The crude product was dissolved in 44 mL of tetrahydrofuran to obtain a first mixture, and KOH (4.94 g, 88 mmol) was dissolved in 33 mL of methanol to obtain a second mixture. The first and second mixtures were then combined and placed in a single-necked round-bottom flask containing a magnetic stir bar, and the mixture was stirred at room temperature for 12 h. After the reaction was complete, the mixture was washed with saturated brine, and the solutions separated into layers. The collected organic phase was dried and then evaporated under reduced pressure (drying temperature: room temperature; drying time: 12 h; temperature during evaporation under reduced pressure: 45 °C; vacuum degree: -0.09 MPa; rotation speed: 100 r / min; time: 1 h). Column chromatography was used to separate and purify the solid, yielding 3.287 g of a white solid, 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene, with a yield of 86.4%.

[0066] (2) The 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene (5 mmol, 1.90 g), 2-iodoaniline (13 mmol, 2.85 g), Pd(PPh3)2Cl2 (0.2 mmol, 0.14 g), and CuI (0.4 mmol, 0.076 g) obtained in step (1) were added to a two-necked flask. After evacuating the flask and purging it with nitrogen three times, 30 mL of tetrahydrofuran and 20 mL of triethylamine solvent were added under a nitrogen atmosphere. The mixture was then slowly heated to 80 °C at room temperature and reacted for 18 h. After the reaction was completed, the solution was washed with saturated brine, separated into layers, and the collected organic phase was dried and then evaporated under reduced pressure (drying temperature: room temperature, drying time: 12 h, temperature during evaporation under reduced pressure: 45 °C, vacuum degree: -0.09 MPa, rotation speed during evaporation under reduced pressure: 100 r / min, time during evaporation under reduced pressure: 1 h). Column chromatography was used to separate and purify the solution, yielding 2.316 g of a yellow solid, which was an o-alkynyl aniline compound, with a yield of 82.3%. High-performance liquid chromatography (HPLC) analysis (conditions: C18 column, acetonitrile / water mobile phase, flow rate: 1.0 mL / min; area normalization method) showed a purity of 93.7%.

[0067] The structural formula of the o-alkynyl aniline compound prepared in Example 5 is as follows: .

[0068] Example 6

[0069] The preparation method of the o-alkynyl aniline compound with aggregation-induced emission properties described in Example 6 consists of the following steps:

[0070] (1) 1,2-Di(4-bromophenyl)-1,2-diphenylene (4.90 g, 10 mmol), Pd(PPh3)2Cl2 catalyst (0.56 g, 0.8 mmol), and CuI catalyst (0.305 g, 1.6 mmol) were added to a two-necked flask. After evacuating the flask three times with nitrogen, 10 mL of tetrahydrofuran and 40 mL of triethylamine solvent were added under a nitrogen atmosphere, followed by the slow addition of trimethylsilylacetylene (2.455 g, 25 mmol). The temperature was raised to 80 °C and the reaction was carried out for 12 h. After the reaction was completed, the flask was washed with saturated brine, the solution was separated into layers, and the collected organic phase was dried and then evaporated under reduced pressure (drying temperature was room temperature, drying time was 12 h, the temperature during evaporation was 45 °C, the vacuum degree during evaporation was -0.09 MPa, the rotation speed during evaporation was 100 r / min, and the evaporation time was 1 h), yielding 4.62 g of intermediate crude product. The crude product was dissolved in 44 mL of tetrahydrofuran to obtain a first mixture, and KOH (4.94 g, 88 mmol) was dissolved in 33 mL of methanol to obtain a second mixture. The first and second mixtures were then combined and placed in a single-necked round-bottom flask containing a magnetic stir bar, and the mixture was stirred at room temperature for 12 h. After the reaction was complete, the mixture was washed with saturated brine, and the solutions separated into layers. The collected organic phase was dried and then evaporated under reduced pressure (drying temperature: room temperature; drying time: 12 h; temperature during evaporation under reduced pressure: 45 °C; vacuum degree: -0.09 MPa; rotation speed: 100 r / min; time: 1 h). Column chromatography was used to separate and purify the solid, yielding 3.287 g of a white solid, 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene, with a yield of 86.4%.

[0071] (2) The 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene (5 mmol, 1.90 g), 2-iodoaniline (15 mmol, 3.29 g), Pd(PPh3)2Cl2 (0.3 mmol, 0.21 g), and CuI (0.5 mmol, 0.095 g) obtained in step (1) were added to a two-necked flask. After evacuating the flask and purging it with nitrogen three times, 30 mL of tetrahydrofuran and 20 mL of triethylamine solvent were added under a nitrogen atmosphere. The mixture was then slowly heated to 80 °C at room temperature and reacted for 18 h. After the reaction was completed, the solution was washed with saturated brine, separated into layers, and the collected organic phase was dried and then evaporated under reduced pressure (drying temperature: room temperature, drying time: 12 h, temperature during evaporation under reduced pressure: 45 °C, vacuum degree: -0.09 MPa, rotation speed during evaporation under reduced pressure: 100 r / min, evaporation time: 1 h). Column chromatography was used to separate and purify the solution, yielding 2.338 g of a yellow solid, which was an o-alkynyl aniline compound, with a yield of 83.1%. High-performance liquid chromatography (HPLC) analysis (conditions: C18 column, acetonitrile / water mobile phase, flow rate: 1.0 mL / min; area normalization method) showed a purity of 94.4%.

[0072] The structural formula of the o-alkynyl aniline compound prepared in Example 6 is as follows: .

[0073] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing an o-alkynyl aniline compound with aggregation-induced emission properties, characterized in that: The reaction consists of the following steps: (1) 1,2-bis(4-bromophenyl)-1,2-diphenylphenyl, bis(triphenylphosphine)-palladium dichloride and cuprous iodide are added to a reaction vessel. Solvent is added to the reaction system under a nitrogen atmosphere. Then, trimethylsilylacetylene is added dropwise. The temperature is raised to 60-80℃ and the reaction is carried out for 8-14 hours. After the reaction is completed, an intermediate crude product is obtained after the first post-treatment. The intermediate crude product is dissolved in tetrahydrofuran to obtain a first mixture. KOH is dissolved in methanol to obtain a second mixture. Then, the first mixture and the second mixture are stirred and mixed at room temperature. After the reaction is completed, a second post-treatment is carried out. 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene was prepared; (2) 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene, 2-iodoaniline, bis(triphenylphosphine)-palladium dichloride and cuprous iodide were added to a reaction vessel, and a solvent was added under a nitrogen atmosphere. The temperature was raised to 60-80℃ and the reaction was carried out for 8-18 hours. After the reaction was completed, the o-ynylaniline compounds were prepared by post-treatment; wherein: the molar ratio of trimethylsilylacetylene to 1,2-bis(4-bromophenyl)-1,2-diphenylstyrene in step (1) was 2-3:1; the molar ratio of 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene to 2-iodoaniline in step (2) was 1:2-3; the structural formula of the o-ynylaniline compounds prepared in step (2) is: The chemical reaction equations involved in step (1) are as follows: The chemical reaction equations involved in step (2) are as follows: 。 2. The method for preparing o-alkynyl aniline compounds with aggregation-induced emission properties according to claim 1, characterized in that: In step (1), the molar amount of palladium dichloride of bis(triphenylphosphine) is 4% or 8% of the molar amount of 1,2-bis(4-bromophenyl)-1,2-stilbene, and the molar amount of cuprous iodide is 16% of the molar amount of 1,2-bis(4-bromophenyl)-1,2-stilbene; the solvent in step (1) is a mixture of tetrahydrofuran and triethylamine, wherein the volume ratio of tetrahydrofuran to triethylamine is 1:

4.

3. The method for preparing o-alkynyl aniline compounds with aggregation-induced emission properties according to claim 1, characterized in that: The first post-treatment described in step (1) is to wash the product with saturated brine after the reaction, separate the solution into layers, dry the collected organic phase, and then evaporate it under reduced pressure to obtain the intermediate crude product. The drying temperature is room temperature, the drying time is 12 h, the reduced pressure drying temperature is 45 °C, the reduced pressure drying vacuum degree is -0.09 MPa, the rotation speed during reduced pressure drying is 100 r / min, and the reduced pressure drying time is 1 h.

4. The method for preparing o-alkynyl aniline compounds with aggregation-induced emission properties according to claim 1, characterized in that: In step (1), the mass-to-volume ratio of the intermediate crude product to tetrahydrofuran in the first mixture is 4.36-4.62 : 41.5-44, in g / mL; in step (1), the mass-to-volume ratio of KOH to methanol in the second mixture is 4.66-4.94 : 31-33, in g / mL; in step (1), the mass ratio of the intermediate crude product in the first mixture to KOH in the second mixture is 4.36-4.62 : 4.66-4.

94.

5. The method for preparing o-alkynyl aniline compounds with aggregation-induced emission properties according to claim 1, characterized in that: The stirring reaction time in step (1) is 12h; the second post-treatment in step (1) is washing with saturated brine after the reaction, separating the solution into layers, drying the collected organic phase, and then purifying it by vacuum rotary evaporation and column chromatography to obtain 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene. The drying temperature is room temperature, the drying time is 12h, the vacuum rotary evaporation temperature is 45℃, the vacuum degree of vacuum rotary evaporation is -0.09MPa, the rotation speed during vacuum rotary evaporation is 100r / min, and the vacuum rotary evaporation time is 1h.

6. The method for preparing o-alkynyl aniline compounds with aggregation-induced emission properties according to claim 1, characterized in that: In step (2), the molar amount of palladium dichloride in bis(triphenylphosphine) accounts for 2%-6% of the molar amount of 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene; in step (2), the molar amount of cuprous iodide accounts for 2%-10% of the molar amount of 1,2-bis(4-ethynylphenyl)-1,2-diphenylethylene.

7. The method for preparing o-alkynyl aniline compounds with aggregation-induced emission properties according to claim 1, characterized in that: The solvent in step (2) is a mixture of tetrahydrofuran and triethylamine, wherein the volume ratio of tetrahydrofuran to triethylamine is 3:

2.

8. The method for preparing o-alkynyl aniline compounds with aggregation-induced emission properties according to claim 1, characterized in that: The post-treatment described in step (2) involves washing with saturated brine after the reaction, separating the solution into layers, drying the collected organic phase, and then purifying it by vacuum rotary evaporation and column chromatography to obtain o-alkynyl aniline compounds. The drying temperature is room temperature, the drying time is 12 h, the vacuum rotary evaporation temperature is 45 °C, the vacuum degree of vacuum rotary evaporation is -0.09 MPa, the rotation speed during vacuum rotary evaporation is 100 r / min, and the vacuum rotary evaporation time is 1 h.

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