A fully visible light-driven fluorescently lit diarylethene organic compound, its preparation method and application

Abstract

This invention discloses a fully visible light-driven, high-fluorescence-quantum-yield, fluorescently lit diarylethylene organic compound and its preparation method. The structure of this high-fluorescence-quantum-yield, fluorescently lit diarylethylene organic compound is shown in general formula (1), where R1 represents an aromatic functional group. All fluorescently lit diarylethylene photochromic materials of this invention can achieve fully visible light-driven open-ring to closed-ring conversion and exhibit extremely high fluorescence quantum yield in the closed-ring form.

Description

Technical Field

[0001] This invention relates to photochromic materials, and particularly to a novel fully visible light-driven, high fluorescence quantum yield, fluorescence-illuminated diarylethene photochromic material. Background Technology

[0002] Fluorescent diarylethylene materials, due to their unique photophysical properties—non-fluorescent in their open-ring form and fluorescent in their closed-ring form—have been widely used in recent years in fields such as sensing, gating, anti-counterfeiting, and super-resolution microscopy of biological organisms, making them a promising class of materials for commercialization. However, 1) the absorption of most fluorescent diarylethylene molecules in their open-ring form, whether in the solid or in solution, is located only in the ultraviolet region, meaning that these molecules can only undergo the conversion from open-ring to closed-ring form under ultraviolet light irradiation; 2) the fluorescence quantum yield of the closed-ring form of most fluorescent diarylethylene molecules is generally low, limiting their application in super-resolution fluorescence imaging. This is because, on the one hand, ultraviolet light affects the stability of the molecules themselves, and prolonged ultraviolet irradiation will inevitably cause uncontrollable photochemical side reactions, leading to molecular aging; on the other hand, the low fluorescence quantum yield will increase the signal-to-noise ratio in super-resolution fluorescence imaging of biological organisms, resulting in poor imaging effects. Therefore, it is of great significance to develop a high fluorescence quantum yield fluorescently lit diarylethene molecule that undergoes photo-cyclization conversion from open-ring (closed-ring) to closed-ring (open-ring) via fully visible light. Summary of the Invention

[0003] To address the aforementioned problems in existing technologies, a strategy of connecting aromatic rings at positions 4 and 4' on the existing fluorescently lit diarylethylene molecular backbone can be adopted. This strategy can increase the degree of conjugation of the molecule, causing the absorption edge of the open-ring form to red-shift to the visible light region, and can also improve the absorption intensity of the closed-ring form (i.e., increase the oscillator intensity). This results in a fluorescently lit diarylethylene photochromic material that can achieve visible light-driven high fluorescence quantum yield.

[0004] The technical solution of the present invention is as follows:

[0005] A diarylethene organic compound with high fluorescence quantum yield, the structure of which is shown in general formula (1):

[0006]

[0007] R1 is a substituted or unsubstituted aryl group;

[0008] The substituents on the aryl group are selected from one or more of C1-C4 alkyl, C1-C4 alkoxy, substituted amino, and trifluoromethyl.

[0009] As a preferred embodiment, R1 in general formula (1) represents one of the following structures:

[0010]

[0011] Preferably, the fully visible light-driven, high fluorescence quantum yield, fluorescence-illuminated diarylethylene organic compound is one of the following specific compounds:

[0012]

[0013]

[0014]

[0015] Preferably, R1 is a substituted or unsubstituted phenyl group;

[0016] The substituents on the aryl group are selected from one or more C1 to C4 alkyl groups.

[0017] Preferably, the diarylethene organic compound is compound 1, 2, or 3, with the following structural formula:

[0018]

[0019] The present invention also provides a method for preparing the diarylethylene organic compound, comprising:

[0020] Under an inert atmosphere, the iodinated compound and the aromatic cycloboronic acid compound were dissolved in tetrahydrofuran, and then Pd(PPh3)4 and saturated potassium carbonate solution were added. The mixture of the above reactants was refluxed for 12-24 h. After the reaction mixture was cooled to room temperature, it was extracted with ethyl acetate, the organic phases were combined, dried over anhydrous Na2SO4 and evaporated to dryness. The target product was obtained by silica gel column chromatography.

[0021] The reaction formula is as follows:

[0022]

[0023] Preferably, the molar ratio of the iodinated compound to the aromatic cyclic borate compound is 1:2.4-2.6, the molar ratio of Pd(PPh3)4 to the borate compound is 0.1:0.9-1.1, and the volume ratio of saturated potassium carbonate solution to tetrahydrofuran is 0.5:0.9-1.1.

[0024] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0025] The compounds of this invention are constructed based on aromatic rings and their derivatives linked to the 4' and 4' positions of the Me-TTO4 molecular backbone. The connection of the aromatic rings at the 4' and 4' positions leads to a decrease in the HOMO-LUMO band gap in the open-ring state, resulting in a redshift in the absorption spectrum of the open-ring state, with the absorption edge located in the visible light region. This enables fully visible-light-driven photocyclization reactions between the open-ring and closed-ring states. Furthermore, the absorption intensity of the closed-ring state is significantly enhanced after the introduction of the aromatic rings compared to the molecular backbone, i.e., the oscillator intensity of the molecule increases, thereby enhancing the fluorescence quantum yield. All of the above results have been verified by density functional theory calculations and experiments, demonstrating the excellent application prospects of this novel diarylethene molecule. Detailed Implementation

[0026] The present invention will now be described in detail with reference to the embodiments.

[0027] Example 1: Synthesis of Compound 1:

[0028] Synthesis route:

[0029]

[0030] In a 50 mL double-necked flask, intermediate iodomethacin-TTO4 (0.19 g, 0.30 mmol), phenylboronic acid (0.09 g, 0.72 mmol), and 10 mL of tetrahydrofuran solution were added sequentially and stirred until dissolved. Then, 5 mL of saturated K₂CO₃ solution and Pd(PPh₃)₄ (0.09 g, 0.08 mmol) were added. The solution was degassed with nitrogen for approximately 15 minutes and then refluxed for 8 hours. After cooling the reaction mixture to room temperature, it was extracted with ethyl acetate, and the combined organic phases were dried over anhydrous Na₂SO₄ and evaporated to dryness. Purification by silica gel column chromatography (DCM / hexane = 1:3) yielded 1 (0.13 g, 82%). 1 H NMR (400MHz, CDCl3): δ[ppm]1.99-1.25(t,6H),2.23-2.27(m,9H),6.63(s,1H),7.30-7.63(m,10H),; 13 C NMR (100MHz, CDCl3): δ[ppm]146.44,138.90,137.38,137.19,135.30,132.12,130.01,129.86,127.64,12 7.56,126.94,126.67,125.38,125.08,122.77,122.23,121.99,121.94,15.7,11.7,8.61,8.33.HRMS[M+H] + calcd.forC 29 H 26O4S3:534.0993, found 534.0978.

[0031] Example 2: Synthesis of Compound 2:

[0032] Synthesis route:

[0033]

[0034] In a 50 mL double-necked flask, iodomethacin-TTO4 (0.19 g, 0.30 mmol), 2-methylphenylboronic acid (0.10 g, 0.72 mmol), and 10 mL of tetrahydrofuran solution were added sequentially and stirred until dissolved. Then, 5 mL of saturated K2CO3 solution and Pd(PPh3)4 (0.09 g, 0.08 mmol) were added. The solution was degassed with nitrogen for approximately 15 minutes and then refluxed for 8 hours. After cooling the reaction mixture to room temperature, it was extracted with ethyl acetate, and the combined organic phases were dried over anhydrous Na2SO4 and evaporated to dryness. Purification by silica gel column chromatography (DCM / hexane = 1:3) yielded 2 (0.13 g, 80%). 1 H NMR (400MHz, CDCl3): δ[ppm]1.92-2.24(m,6H),2.23-2.27(m,9H),2.48-2.50(m,6H),6.64(s,1H),7.41-7.62(m,8H); 13 C NMR (100MHz, CDCl3): δ[ppm]148.42,140.38,140.04,136.42,134.91,132.17,129.98,129.84,128.90,127.5 3,124.84,124.64,123.73,123.09,121.97,121.94,121.82,118.91,19.2,15.8,11.8,8.60,8.28.HRMS[M+H] + calcd.for C 31 H 30 O4S3:562.1306, found 536.1409.

[0035] Example 3: Synthesis of Compound 3:

[0036] Synthesis route:

[0037]

[0038] In a 50 mL double-necked flask, iodomethacin-TTO4 (0.19 g, 0.30 mmol), 2,5-dimethylphenylboronic acid (0.11 g, 0.72 mmol), and 10 mL of tetrahydrofuran solution were added sequentially and stirred until dissolved. Then, 5 mL of saturated K2CO3 solution and Pd(PPh3)4 (0.09 g, 0.08 mmol) were added. The solution was degassed with nitrogen for approximately 15 minutes and then refluxed for 8 hours. After cooling the reaction mixture to room temperature, it was extracted with ethyl acetate, and the combined organic phases were dried over anhydrous Na2SO4 and evaporated to dryness. Purification by silica gel column chromatography (DCM / hexane = 1:3) yielded 3 (0.15 g, 85%). 1 H NMR (400MHz, CDCl3): δ[ppm]1.90-2.22(m,6H),2.24-2.28(m,9H),2.47-2.51(m,12H),6.64(s,1H),7.30-7.61(m,8H); 13 C NMR (100MHz, CDCl3): δ[ppm]148.04,140.59,139.97,136.19,134.87,132.13,130.82,130.00,129.86,127.4 4,124.87,124.77,122.99,122.63,122.37,121.97,121.93,120.16,19.5,15.7,11.8,8.59,8.28.HRMS[M+H] + calcd.for C 33 H 34 O4S3:590.1619, found 590.1666.

[0039] The vertical absorption energy, oscillator strength, HOMO / LUMO energy level, and band gap between HOMO and LUMO were quantitatively calculated for the open-ring and closed-ring forms of compounds 1, 2, and 3 of this invention, respectively; the maximum emission, fluorescence quantum yield, fluorescence lifetime, and S1 energy level were tested, and the results are shown in Table 1.

[0040] Table 1: Theoretical calculations and experimental data for molecules 1, 2, and 3

[0041]

[0042]

[0043] The above experimental results show that the absorption edges of the open-ring forms of compounds 1, 2 and 3 of this application are located in the visible light region, while the closed-ring forms have extremely high fluorescence quantum efficiency. They can successfully achieve visible light-driven cyclization and high fluorescence quantum yield, and have good application prospects.

[0044] While the invention has been disclosed through embodiments and preferred embodiments, it should be understood that the invention is not limited to the disclosed embodiments. Rather, those skilled in the art will appreciate that it is intended to cover various variations and similar arrangements. Therefore, the scope of the appended claims should be consistent with the broadest interpretation to cover all such variations and similar arrangements.

Claims

1. A diarylethylene organic compound, characterized in that, The structure is shown in general formula (1): In general formula (1), R1 represents one of the following structures:

2. The diarylethylene organic compound according to claim 1, characterized in that, The diarylethene organic compounds 1, 2, or 3 have the following structural formulas:

3. The use of a diarylethylene organic compound as described in any one of claims 1 to 2 in the preparation of photochromic materials.

4. The application of the diarylethylene organic compound according to claim 3 in the preparation of photochromic materials, characterized in that, The photochromic material is a fully visible light-driven photochromic material.

5. An anti-counterfeiting ink, characterized in that, Organic compounds containing diarylethene as described in any one of claims 1 to 2.

6. A method for preparing a diarylethylene organic compound as described in any one of claims 1 to 2, characterized in that, include: Under an inert atmosphere, the iodinated compound and the aromatic cycloboronic acid compound were dissolved in tetrahydrofuran, and then Pd(PPh3)4 and saturated potassium carbonate solution were added. The mixture of the above reactants was refluxed for 12-24 h. After the reaction mixture was cooled to room temperature, it was extracted with ethyl acetate, the organic phases were combined, dried over anhydrous Na2SO4 and evaporated to dryness. The target product was obtained by silica gel column chromatography. The reaction formula is as follows:

7. The method for preparing the diarylethylene organic compound according to claim 6, characterized in that, The molar ratio of the iodinated compound to the aromatic borate compound is 1:2.4-2.6, the molar ratio of Pd(PPh3)4 to the borate compound is 0.1:0.9-1.1, and the volume ratio of saturated potassium carbonate solution to tetrahydrofuran is 0.5:0.9-1.1.

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