Bisanthene compound with lactone unit embedded therein as well as synthesis method and application of bisanthene compound

Abstract

The invention relates to the technical field of organic functional molecule synthesis, and particularly discloses a lactone unit embedded bissanthin compound as well as a synthesis method and application thereof. According to the method, a synthesis strategy from bottom to top is adopted, and a lactone unit is embedded into bay area positions on two sides of bissanthin, so that a compound A is successfully obtained. Meanwhile, the compound A shows a self-absorption characteristic under different solution concentrations, and when the compound A is prepared into nano particles, the nano particles show relatively high stability and 65% photothermal conversion efficiency in a photothermal performance test.

Description

Technical Field

[0001] This invention relates to a compound with a lactone unit embedded in bisanthene, its synthesis method, and its application, belonging to the field of organic functional molecule synthesis technology. Background Technology

[0002] Nano-sized fused-ring aromatics (FRAs) exhibit great potential in fields such as electronic devices, bioimaging, and energy technologies due to their excellent two-dimensional π-conjugated structure. By precisely doping with heteroatoms, their framework and electron cloud distribution can be reconstructed at the molecular level, thereby systematically controlling key properties such as redox activity, energy band gap, charge transfer, and photothermal conversion. However, compared to heteroatoms such as nitrogen, boron, sulfur, and silicon, cases of oxygen atoms embedded in the framework of FRAs remain scarce. To date, reported oxygen-containing FRA systems are mainly limited to furan or pyran structures, whose mixed-valence cations exhibit excellent semiconductor properties. Therefore, developing more types of oxygen-doped FRAs is of significant value.

[0003] Lactone groups are stable and strongly electron-deficient oxygen-doped units, highly favored in polymer semiconductors due to their high electron mobility; however, their introduction into two-dimensional nano-fused-ring aromatic hydrocarbons is rarely reported. This strategy offers several advantages: First, it can address the low stability of extended π-conjugated systems while preserving the inherent aromaticity of the molecule, thereby improving overall optical absorption, emission, and solid-state properties. Furthermore, the unique Diels-Alder reactivity of lactones endows them with modular expansion capabilities, allowing for the precise construction of more complex functional molecules.

[0004] In this invention, compound A was successfully synthesized by embedding lactone groups in the bay regions on both sides of the bisanthene. This molecule not only enhances the stability of the functional molecule, but the synthesized compound A, when prepared into nanoparticles for use as a photothermal agent, exhibits high stability and a photothermal conversion efficiency of 65% in photothermal performance tests. Summary of the Invention

[0005] To address the above problems, this invention provides a compound with a lactone unit embedded in bisanthene, its synthetic method, and its application. This method has the advantages of simple operation, atom economy, high chemical selectivity, and high yield.

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

[0007] A compound with a lactone unit embedded in bisanthene has the following structure:

[0008] A method for synthesizing a compound containing a lactone unit embedded in bisanthene, comprising the following steps: using compound 1 as a starting material, compound A is obtained via a Vilsmeier–Haack reaction and an oxidation reaction involving K₂S₂O₈. The synthetic steps of this compound are shown below:

[0009] The synthesis method of A mentioned above specifically includes the following steps:

[0010] Step 1: According to the mass ratio of compound 1: potassium persulfate: tetraethylammonium bromide = 1:1.32:0.10, dissolve it in 1,2-dichloroethane solvent. The reaction mixture is stirred at 80°C for 12 hours. After the reaction is complete, filter the reaction solution through diatomaceous earth, collect the filtrate, and recover the solvent by vacuum distillation. Use a mixed solvent of petroleum ether and dichloromethane at a volume ratio of 5:1 as the eluent, and separate the solution using a 200-300 mesh neutral silica gel column. Collect the first green band to obtain a solution of compound 2. Then, recover the solvent by vacuum distillation and dry under vacuum to obtain a blue-green solid compound 2.

[0011] Step 2: Compound 2, phosphorus oxychloride, and N,N-dimethylformamide were dissolved in 1,2-dichloroethane at a mass ratio of 1:0.36:5.82. The reaction mixture was stirred at 90°C for 2 hours. After the reaction was complete, the mixture was cooled to room temperature, and 3 mL of 20 wt% sodium hydroxide solution was slowly added dropwise to quench the reaction. The mixture was extracted with ethyl acetate and water. The resulting organic phase was dried over anhydrous sodium sulfate and concentrated under reduced pressure. The solution was separated by 200-300 mesh neutral silica gel column chromatography using a 2:1 (v / v) mixture of petroleum ether and dichloromethane as eluent. The third blue-green band was collected to obtain a solution of compound 3. The solvent was then recovered by reduced pressure distillation, and the solution was dried under vacuum to obtain a black solid, compound 3.

[0012] Step 3: According to the mass ratio of compound 3: potassium persulfate: tetraethylammonium bromide = 1:1.32:0.10, dissolve it in 1,2-dichloroethane solvent. The reaction mixture is stirred at 80°C for 8 hours. After the reaction is completed, filter the reaction solution through diatomaceous earth, collect the filtrate, and recover the solvent by vacuum distillation. Use a mixed solvent of petroleum ether and dichloromethane with a volume ratio of 1:1 as the eluent, and separate the solution using a 200-300 mesh neutral silica gel column chromatography. Collect the second green band to obtain a solution of compound A. Then, recover the solvent by vacuum distillation and dry under vacuum to obtain a blue-green solid compound A.

[0013] One application of a compound with a lactone unit embedded in bisanthene is that the synthesized compound A is prepared into nanoparticles for use as a photothermal agent, exhibiting high stability and a photothermal conversion efficiency of 65% in photothermal performance tests.

[0014] The beneficial effects of this invention are as follows:

[0015] (1) The synthetic method for inserting lactone units into bisanthene compounds proposed in this invention is simple to operate and has a high yield. The synthesized compound A effectively improves the chemical stability of bisanthene.

[0016] (2) Compound A, synthesized by embedding lactone units into bisanthene, was made into nanoparticles and used as a photothermal agent. It showed good stability and 65% photothermal conversion efficiency in photothermal performance tests. Attached Figure Description

[0017] Figure 1 This is the synthetic route diagram for compound A.

[0018] Figure 2 This is the 1H NMR spectrum of compound 1.

[0019] Figure 3 This is the 1H NMR spectrum of compound 2.

[0020] Figure 4 This is the 1H NMR spectrum of compound 3.

[0021] Figure 5 This is the 1H NMR spectrum of compound A.

[0022] Figure 6 (A) is a single crystal structure diagram of compound A; (B) is the packing arrangement of compound A in the unit cell.

[0023] Figure 7 (A) is the UV-Vis absorption spectrum of compound A in different solvents; (B) is the concentration-dependent fluorescence emission spectrum of compound A.

[0024] Figure 8 The figure shows the concentration-dependent photothermal heating curve of nanoparticle A under irradiation with a 660 nm laser (0.5 W cm⁻²).

[0025] Figure 9 The graph shows the thermal conversion efficiency of nanoparticles of compound A.

[0026] Figure 10 The photothermal stability experiment of compound A nanoparticles. Detailed Implementation

[0027] The raw material 1 used in this invention was synthesized using the preparation method described in the reference entitled "Synthesis and Properties of Aza-Ovalene with Six Zigzag Edges," and its proton nuclear magnetic resonance (NMR) spectrum data are as follows: Figure 2 The image shows the 1H NMR spectrum of compound 1. 1 H NMR (600 MHz, CDCl3) δ (ppm) = 9.60 (s, 1H), 8.60 (dd, J = 12.7, 7.4 Hz, 2H), 7.92 (d, J = 9.1 Hz, 1H), 7.67 – 7.57 (m, 4H), 7.50 (d, J =8.6 Hz, 1H), 7.46 (d, J = 8.4 Hz, 1H), 7.39 (d, J = 8.8 Hz, 1H), 7.28 (d, J = 6.6Hz, 1H), 7.17 (s, 4H), 2.49 (d, J = 2.9 Hz, 6H), 1.88 (d, J = 3.5 Hz, 12H).

[0028] Example 1. Synthesis of Compound 2

[0029] 122.9 mg (0.2 mmol) of compound 1, 162.2 mg (0.6 mmol) of potassium persulfate, 19.3 mg (0.06 mmol) of tetraethylammonium bromide, and 10 mL of 1,2-dichloroethane were added to a 50 mL double-necked flask. The reaction mixture was stirred at 80 °C for 12 hours. After the reaction was completed, the reaction solution was filtered through diatomaceous earth, and the filtrate was collected. The solvent was recovered by vacuum distillation. Using a mixed solvent of petroleum ether and dichloromethane at a volume ratio of 5:1 as the eluent, the solution was separated by 200-300 mesh neutral silica gel column chromatography. The first green band was collected to obtain a solution of compound 2. The solvent was then recovered by vacuum distillation, and the solution was dried under vacuum to obtain a blue-green solid compound 2, totaling 103.0 mg, with a yield of 82%.

[0030] Figure 3 The 1H NMR spectrum of compound 2 is shown below:¹H NMR (600 MHz, CDCl₃) δ (ppm) = 8.73 (d , J = 7.4 Hz, 1H), 8.68 (d , J= 7.5 Hz, 1H), 8.13 (d , J = 9.3 Hz, 1H), 7.79–7.61 (m, 5H), 7.58 (d , J = 8.3 Hz, 1H), 7.44 (d , J = 8.9 Hz, 1H), 7.17 (s, 4H), 2.50 (s, 6H), 1.88 (d , J = 11.7 Hz, 12H).

[0031] Example 2. Synthesis of Compound 3

[0032] 125.7 mg (0.2 mmol) of compound 2, 45.3 mg (0.3 mmol) of phosphorus oxychloride, 731.6 mg (10 mmol) of N,N-dimethylformamide, and 8 mL of 1,2-dichloroethane were added to a 25 mL double-necked flask. The reaction mixture was stirred at 90 °C for 2 hours. After the reaction was completed, the mixture was cooled to room temperature, and 3 mL of 20 wt% sodium hydroxide solution was slowly added dropwise to quench the reaction. The mixture was extracted with ethyl acetate and water. The resulting organic phase was dried over anhydrous sodium sulfate and concentrated under reduced pressure. The solution was separated by 200-300 mesh neutral silica gel column chromatography using a 2:1 (v / v) mixture of petroleum ether and dichloromethane as eluent. The third blue-green band was collected to obtain a solution of compound 3. The solvent was then recovered by reduced pressure distillation, and the solution was dried under vacuum to obtain a black solid of compound 3, totaling 102.4 mg, with a yield of 78%.

[0033] Figure 4 The 1H NMR spectrum of compound 3 is shown below: ¹H NMR (600 MHz, CDCl3) δ (ppm) = 9.91 (s, 1H), 8.40 (d) , J = 9.1 Hz, 1H), 8.29 (d , J = 8.9 Hz, 1H), 8.04 (d , J = 8.4Hz, 1H), 8.00 (d , J = 9.3 Hz, 1H), 7.94 (t, J = 7.9 Hz, 1H), 7.87 (d , J = 9.3 Hz, 1H), 7.78 (d , J = 8.9 Hz, 1H), 7.74 (d , J = 7.3 Hz, 1H), 7.71 (d , J= 9.1 Hz,1H), 2.53 (s, 6H), 1.88 ( d, J = 4.1 Hz, 12H).

[0034] Example 3. Synthesis of Compound A

[0035] 131.3 mg (0.2 mmol) of compound 3, 162.2 mg (0.6 mmol) of potassium persulfate, 19.3 mg (0.06 mmol) of tetraethylammonium bromide, and 10 mL of 1,2-dichloroethane were added to a 50 mL double-necked flask. The reaction mixture was stirred at 80 °C for 8 hours. After the reaction was completed, the reaction solution was filtered through diatomaceous earth, and the filtrate was collected. The solvent was recovered by vacuum distillation. Using a 1:1 mixture of petroleum ether and dichloromethane as the eluent, the solution was separated by 200-300 mesh neutral silica gel column chromatography. The second green band was collected to obtain a solution of compound A. The solvent was then recovered by vacuum distillation, and the solution was dried under vacuum to obtain a blue-green solid compound A, totaling 113.9 mg, with a yield of 85%.

[0036] Figure 5 Here is the 1H NMR spectrum of compound A: 1 H NMR (600 MHz, C6D6) δ (ppm) = 8.46 (d, J = 9.0 Hz, 2H), 7.75 (d, J = 9.3 Hz, 2H), 7.68 (d, J = 9.0 Hz, 2H), 7.37 (d, J =9.2 Hz, 2H), 7.10 – 7.06 (m, 4H), 2.40 (s, 6H), 1.91 (s, 6H), 1.81 (s, 6H).

[0037] Structural characterization of compound A in this embodiment

[0038] The single-crystal cultivation method of compound A in this embodiment

[0039] The single crystals of compound A were cultured using the solvent diffusion method. The specific steps are as follows: First, 0.1 mL of a 10... -3A dichloromethane solution of compound A (M) was filtered through an organic microporous membrane with a pore size of 0.45 μm and then added to a smooth glass tube with an inner diameter of 5 mm and a length of 10 mm. This glass tube was then placed inside a sealed glass bottle (20 mm outer diameter, 80 mm height) containing 2 mL of n-hexane, ensuring the opening of the glass tube was above the hexane level. Finally, the glass tube was placed at an angle inside the small glass bottle and stored in a cool, dark, and vibration-free environment. After three days of slow evaporation and diffusion, a single crystal with a regular morphology was finally obtained. Figure 6 (A) is a schematic diagram of a single crystal of compound A. Figure 6 (B) represents the stacking pattern of compound A in the unit cell.

[0040] This example studies the UV-Vis and near-infrared absorption spectra of compound A in different solvents and its emission spectra in dichloromethane solutions of different concentrations.

[0041] Use a concentration of 1×10 -5 Compound A of M was tested. The UV-Vis and near-infrared absorption spectra in different solvents (n-hexane, toluene, dichloromethane, ethyl acetate, and tetrahydrofuran) were measured using a SHIMADZU UV-2600i UV-Vis spectrophotometer. The results are shown in the attached figure. Figure 7 As shown in (A), the maximum absorption wavelength of compound A is 703 nm. Furthermore, compound A exhibits a positive solvation effect in different solvents. The absorption wavelengths of compound A at different concentrations (5 × 10⁻⁶) were measured using a HITACHI F-4700 fluorometer. -6 M, 1×10 -5 M, 2.5×10 -5 M, 5×10 -5 M, 7.5×10 -5 M, 1×10 -4 The fluorescence emission spectra under M conditions are shown in the attached figure. Figure 7 As shown in (B), compound A exhibits a fluorescence emission range of 715-1100 nm and displays self-absorption characteristics under different concentration conditions. With increasing concentration, at 1×10⁻⁶ nm... -4 This self-absorption characteristic reaches its maximum value at time M.

[0042] Preparation of nanoparticles in Example A of this embodiment

[0043] 2 mg of compound A and 10 mg of DSPE-PEG were mixed. 2000The nanoparticles were dissolved in 2 mL of tetrahydrofuran solution and then added to 10 mL of double-distilled water for sonication (150 W). The resulting dispersion was then sonicated (150 W) for 5 minutes. Subsequently, the dispersion was dialyzed for 12 hours to obtain a homogeneous and transparent dark blue or dark green micelle solution, which was then filtered using a 0.45 μm polyvinylidene fluoride syringe. The resulting concentrated nanoparticle solution could be diluted with phosphate buffer solution. Finally, the nanoparticles were stored at 4 °C for subsequent use.

[0044] This embodiment evaluates the photothermal properties and stability of nanoparticle A.

[0045] Under 660 nm laser irradiation (power density of 0.5 W cm⁻², irradiation time of 4 minutes), the temperature of A nanoparticles rapidly increased, reaching 81.22 °C at a concentration of 200 µM. The temperature increase of A nanoparticles was positively correlated with both its concentration and the laser power density, as shown in the attached figure. Figure 8 As shown, this demonstrates that heat generation can be effectively controlled by adjusting these parameters. Using the method reported in the literature (Highly Stable Near-Infrared II Luminescent Diradicaloids for Cancer Phototheranostics), the photothermal conversion efficiency of the A nanoparticles was calculated to be 65%. Specific results are shown in the appendix. Figure 9 Furthermore, the photothermal stability of the nanoparticles was verified by subjecting them to four heating-cooling cycles under continuous laser irradiation, and the results are shown in the attached figure. Figure 10 As shown, the highest temperature in each cycle remains consistent, demonstrating good photothermal stability.

[0046] Obviously, the above embodiments are merely illustrative of the present invention and do not limit the implementation of the present invention. For those skilled in the art, other variations or adjustments can be made based on the above description. It is impossible to exhaustively list all embodiments here; any obvious variations or adjustments that pertain to the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. A compound in which a lactone unit is embedded in bisanthene, characterized in that, The structure is as follows: 。 2. A method for synthesizing a compound with a lactone unit intercalated into a bisanthene as described in claim 1, characterized in that, Compound A was obtained via the following synthetic route. 。 3. A method for synthesizing a compound with a lactone unit intercalated into a bisanthene as described in claim 2, characterized in that, In the reaction of compound 1 with K2S2O8 to generate compound 2, the mass ratio of compound 1 to potassium persulfate is 1:1.32, the mass ratio of compound 1 to tetraethylammonium bromide is 1:0.10, the solvent is 1,2-dichloroethane at a concentration of 50 L / mol of compound 1, the reaction temperature is 80 °C, and the reaction time is 12 hours. After the reaction is completed, the reaction system is purified by extraction, drying, filtration, vacuum distillation, and silica gel column chromatography to obtain product 2.

4. A method for synthesizing a compound with a lactone unit intercalated into a bisanthene as described in claim 2, characterized in that, In the reaction of compound 2 with phosphorus oxychloride and N,N-dimethylformamide to generate compound 3, the mass ratio of compound 2 to phosphorus oxychloride was 1:0.36, the mass ratio of compound 2 to N,N-dimethylformamide was 1:5.82, the solvent was 1,2-dichloroethane at a concentration of 40 L / mol of compound 2, the reaction temperature was 90 °C, and the reaction time was 2 hours. After the reaction was completed, the reaction system was purified by extraction, drying, filtration, vacuum distillation, and silica gel column chromatography to obtain product 3.

5. A method for synthesizing a compound with a lactone unit intercalated into a bisanthene as described in claim 2, characterized in that, In the reaction of compound 3 with K2S2O8 to generate compound A, the mass ratio of compound 3 to potassium persulfate is 1:1.32, the mass ratio of compound 3 to tetraethylammonium bromide is 1:0.10, the solvent is 1,2-dichloroethane at a concentration of 50 L / mol of compound 3, the reaction temperature is 80 °C, and the reaction time is 8 hours. After the reaction is completed, the reaction system is purified by extraction, drying, filtration, vacuum distillation, and silica gel column chromatography to obtain product A.

6. An application of a compound with a lactone unit intercalated into a bisanthene as described in claim 1, characterized in that, The synthesized compound A was made into nanoparticles and used as a photothermal agent. In the photothermal performance test, it showed high stability and a photothermal conversion efficiency of 65%.

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