Full visible light response diarylethene compound as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of photochromic compounds, and particularly discloses a photochromic diarylethene compound with full visible light response as well as a preparation method and application of the photochromic diarylethene compound. The compound is prepared by carrying out a coupling reaction on 1, 2-dibromo-4-methoxyphenazine and a specific boric acid ester compound (comprising one or more of 2-methyl-5-phenyl-thiophene boric acid ester and 5-methyl-2-phenyl-thiazole boric acid ester), and the compound is prepared by carrying out a coupling reaction on the 1, 2-dibromo-4-methoxyphenazine and the specific boric acid ester compound (comprising one or more of 2-methyl-5-phenyl-thiophene boric acid ester and 5-methyl-2-phenyl-thiazole boric acid ester). The diarylethene photochromic compound provided by the invention takes phenazine as an alkene bridge, can generate reversible isomerization conversion between an open-loop body and a closed-loop body under irradiation of specific visible light, and has reversible change along with properties such as color, absorption spectrum, fluorescence spectrum and the like of the diarylethene photochromic compound. The invention also provides a preparation method of the compound. The method has the remarkable advantages of simplicity and convenience in operation, low raw material cost, high product safety, easiness in separation and purification, facilitation of industrial production and the like.

Description

Technical Field

[0001] The invention relates to a diarylethene compound responsive to full visible light, a preparation method and an application thereof, and belongs to the technical field of photochromic compounds. Background Art

[0002] In recent years, with the rapid development of modern functional materials science, smart materials with excellent performance have become increasingly integrated into daily life. Among them, optical switch materials have attracted much attention due to their excellent chemical properties and broad application prospects.

[0003] Among the many photochromic materials, diarylethenes stand out due to their unique reversible photocyclization reaction characteristics and the excellent thermal stability of open-ring isomers and closed-ring isomers. These characteristics enable them to exhibit excellent information storage and transmission capabilities and super fatigue resistance in a variety of media and states. However, the photoisomerization reactions (at least one direction) of the currently known diarylethenes photochromic compounds usually require ultraviolet light excitation. The inherent disadvantages of ultraviolet light, such as weak cell killing and tissue penetration, have greatly limited the application expansion of such compounds in fields such as materials science and biomedicine.

[0004] Therefore, developing a photochromic diarylethene compound with full visible light response and providing a simple preparation method and application route thereof, aiming to improve the application safety of the compound, reduce the preparation cost and expand its application scope in the biomedical field, has become an urgent problem to be solved in this field. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention provides a fully visible light-responsive photochromic diarylethene compound, its preparation method, and its application. The present photochromic diarylethene compound overcomes the drawback of existing diarylethene photochromic compounds, which require ultraviolet light to stimulate a photoisomerization reaction, thereby broadening their application range.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A photochromic diarylethene compound responsive to all visible light, having the structure shown in the following formula I:

[0008]

[0009] In formula I, Ar1 and Ar2 groups are independently selected from 2-methyl-5-phenyl-thiophene and 5-methyl-2-phenyl-thiazole.

[0010] According to the present invention, the photochromic diarylethene compound with full visible light response is preferably selected from one of the following compounds:

[0011]

[0012] According to the present invention, the method for preparing the above-mentioned photochromic diarylethene compound with full visible light response comprises the following steps:

[0013] 1,2-dibromo-4-methoxyphenazine, a borate compound, a catalyst, an alkaline substance, water and an organic solvent are uniformly mixed and subjected to a coupling reaction to obtain a photochromic diarylethene compound with full visible light response.

[0014] According to the present invention, the 1,2-dibromo-4-methoxyphenazine has a structure shown in the following formula II; its preparation method is a prior art, and reference can be made to the literature: Potential Chemopreventive Agents Based on the Structure of the Lead Compound 2-Bromo-1-hydroxyphenazine, Isolated from Streptomyces Species, Strain CNS284. Journal of Medicinal Chemistry, 2010, 53(24), 8688-8699.

[0015]

[0016] According to the present invention, preferably, the borate compound comprises one or more of 2-methyl-5-phenyl-thiophene borate and 5-methyl-2-phenyl-thiazole borate; the structural formula of the 2-methyl-5-phenyl-thiophene borate is shown in Formula III below, and the structural formula of the 5-methyl-2-phenyl-thiazole borate is shown in Formula IV below;

[0017]

[0018] According to the present invention, the preparation method of the borate ester compound is a prior art, and reference may be made to the literature: Photon-Quantitative 6π-Electrocyclization of a Diarylbenzo[b]thiophene in Polar Medium. Chemistry-An Asian Journal, 2015, 10, 1725-1730.

[0019] According to the present invention, preferably, the molar ratio of the 1,2-dibromo-4-methoxyphenazine to the borate ester compound is 1-3:2-7, preferably 1.5-2.5:4-6, and more preferably 2:5.

[0020] According to the present invention, the catalyst is preferably tetrakis(triphenylphosphine)palladium, palladium acetate or bis(diphenylphosphino)ferrocenepalladium dichloride; the molar ratio of the catalyst to 1,2-dibromo-4-methoxyphenazine is 0.1-1:1-3, preferably 0.2-0.8:1.5-2.5, and more preferably 0.5:2.

[0021] According to the present invention, the alkaline substance is one or more of sodium carbonate, tripotassium phosphate and cesium carbonate; the molar ratio of the alkaline substance to 1,2-dibromo-4-methoxyphenazine is 40-100:1-3, preferably 60-90:1.5-2.5, and more preferably 80:2.

[0022] According to the present invention, preferably, the ratio of the volume of water to the molar number of 1,2-dibromo-4-methoxyphenazine is 20-50 L:1-3 mol, preferably 35-45 L:1.5-2.5 mol, and more preferably 40 L:2 mol.

[0023] According to the present invention, preferably, the organic solvent is tetrahydrofuran and / or 1,4-dioxane; the ratio of the volume of the organic solvent to the molar number of 1,2-dibromo-4-methoxyphenazine is 20-50L:1-3mol, preferably 35-45L:1.5-2.5mol, and more preferably 40L:2mol.

[0024] Preferably, according to the present invention, the temperature of the coupling reaction is 70-110°C, specifically 75°C, 80°C, 85°C, 90°C, 95°C, 100°C or 110°C; the time of the coupling reaction is 12-48h, specifically 12h, 15h, 18h, 20h, 24h, 28h, 32h, 36h, 40h or 48h; the coupling reaction is carried out under a protective gas atmosphere, and the protective gas is one or more of a rare gas and nitrogen.

[0025] According to the present invention, the reaction liquid obtained from the coupling reaction can be subjected to product separation and characterization according to conventional separation and purification methods; preferably, the specific post-reaction treatment steps are as follows: water is added to the reaction liquid obtained from the coupling reaction for washing, followed by extraction with ethyl acetate 2 to 5 times, the organic phases are combined, the solvent is removed from the obtained organic phases to obtain a crude product, and the obtained crude product is separated and purified by column chromatography, the eluent used for the column chromatography is petroleum ether, n-hexane, a petroleum ether-ethyl acetate mixed solvent or a n-hexane-ethyl acetate mixed solvent, the volume ratio of petroleum ether to ethyl acetate in the petroleum ether-ethyl acetate mixed solvent is 2 to 50:1, and the volume ratio of n-hexane to ethyl acetate in the n-hexane-ethyl acetate mixed solvent is 2 to 50:1; the mesh number of the silica gel used for the column chromatography is 200 to 300 mesh, or 300 to 400 mesh.

[0026] According to the present invention, the above-mentioned photochromic diarylethene compound with full visible light response is used in cell fluorescence imaging, information storage, anti-counterfeiting components and photosensitive liquid crystal materials.

[0027] The technical features and beneficial effects of the present invention are as follows:

[0028] 1. The present invention provides a diarylethene compound with full visible light responsiveness. The diarylethene photochromic compound of the present invention uses 4-methoxyphenazine as an olefin bridge. Under excitation by full visible light, the diarylethene compound undergoes photoinduced molecular structural changes. During this process, the diarylethene compound exhibits significant color changes and significant absorption in the visible light region.

[0029] 2. The present invention also provides a method for preparing a diarylethene compound with full visible light responsiveness. Based on the diarylethene structure, a new photochromic diarylethene compound with photoisomerization reaction is obtained through Suzuki-Miyaura coupling reaction. The synthesis steps are relatively few, the synthesis method is simple, the raw material cost is low, the product is easy to separate and purify, and industrial synthesis is easy to achieve.

[0030] 3. The photochromic diarylethene compound based on phenazine prepared by the present invention has the characteristics of full visible light response, simple structure and short synthesis cycle. Compared with other diarylethene compounds with full visible light response, it is easier to achieve chemical modification. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0032] Figure 1 This is a UV-visible absorption spectrum of the diarylethene compound prepared in Example 1 at different concentrations in chromatographic methanol;

[0033] Figure 2 The UV-visible absorption spectra of the diarylethene compound prepared in Example 1 under different irradiation times in chromatographic methanol;

[0034] Figure 3 The UV-visible absorption spectra of the diarylethene compound prepared in Example 1 at different concentrations in chromatographic acetonitrile are shown;

[0035] Figure 4 The UV-visible absorption spectra of the diarylethene compound prepared in Example 1 in acetonitrile at different irradiation times are shown;

[0036] Figure 5 The UV-visible absorption spectra of the diarylethene compound prepared in Example 1 at different concentrations in chromatographic n-hexane are shown;

[0037] Figure 6 The UV-visible absorption spectra of the diarylethene compound prepared in Example 1 in chromatographic n-hexane at different irradiation times are shown;

[0038] Figure 7 This is a UV-visible absorption spectrum of the diarylethene compound prepared in Example 2 at different concentrations in chromatographic methanol;

[0039] Figure 8 The UV-visible absorption spectra of the diarylethene compound prepared in Example 2 under different irradiation times in chromatographic methanol;

[0040] Figure 9 The UV-visible absorption spectra of the diarylethene compound prepared in Example 2 at different concentrations in chromatographic acetonitrile are shown;

[0041] Figure 10 The UV-visible absorption spectra of the diarylethene compound prepared in Example 2 in chromatographic acetonitrile at different irradiation times are shown;

[0042] Figure 11 This is a UV-visible absorption spectrum of the diarylethene compound prepared in Example 2 at different concentrations in chromatographic n-hexane;

[0043] Figure 12 The UV-visible absorption spectra of the diarylethene compound prepared in Example 2 in chromatographic n-hexane at different irradiation times are shown;

[0044] in, Figures 1 to 12 In the equation, Absorbance refers to the absorbance, and Wavelength refers to the wavelength.

[0045] Figure 13 The fluorescence absorption spectra of the diarylethene compound prepared in Example 1 in chromatographic n-hexane at different irradiation times are shown;

[0046] Figure 14 The fluorescence absorption spectra of the diarylethene compound prepared in Example 2 in chromatographic n-hexane at different irradiation times are shown;

[0047] in, Figures 13-14 In the equation, Fluo.Intensity refers to the fluorescence intensity, and Wavelength refers to the wavelength.

[0048] Figure 15This is a graph showing the fatigue resistance of the diarylethene compound prepared in Example 1;

[0049] Figure 16 This is a graph showing the fatigue resistance of the diarylethene compound prepared in Example 2;

[0050] in, Figures 15-16 In the table, Absorbance refers to the absorbance, and Switching Cycles refers to the switching cycle.

[0051] Figure 17 A first-order function graph is drawn for the absorbance versus time curve of the diarylethene compound prepared in Example 1 in anhydrous toluene;

[0052] Figure 18 An Arrhenius plot showing the reaction rate of the diarylethene compound prepared in Example 1 in anhydrous toluene as a function of temperature;

[0053] Figure 19 A first-order function graph is drawn for the absorbance versus time curve of the diarylethene compound prepared in Example 2 in anhydrous toluene;

[0054] Figure 20 This is an Arrhenius plot showing the reaction rate of the diarylethene compound prepared in Example 2 in anhydrous toluene as a function of temperature.

[0055] Figure 21 This is a fluorescence imaging diagram of the diarylethene compound prepared in Example 1 in A549 cells.

[0056] Figure 22 This is the fluorescence imaging of the diarylethene compound prepared in Example 2 in A549 cells. DETAILED DESCRIPTION

[0057] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0058] The preparation methods of compounds 1 to 3 in Examples 1 to 2 of the present invention do not limit the present invention.

[0059] Example 1

[0060] A method for preparing a photochromic diarylethene compound with full visible light response comprises the following steps:

[0061] (1) Preparation of Compound 1

[0062] The reaction route is as follows:

[0063]

[0064] To a reaction flask, 3-bromo-1-methoxy-phenazine (100 mg, 0.35 mmol), acetic acid (20 μL), and chloroform (0.28 mL) were added and stirred to dissolve. Liquid bromine (18.2 μL, 0.35 mmol) was added to the reaction system and the reaction was stirred at room temperature for 24 hours. After the reaction, 10 mL of saturated aqueous Na₂S₂O₃ was added to the reaction system to quench the bromine. Simultaneously, the color of the system changed from tan to turbid yellow. The product was extracted three times with 50 mL of ethyl acetate (50 mL x 3). The resulting organic phase was evaporated to remove the solvent, yielding a crude yellow solid. This product was purified by column chromatography (eluent: petroleum ether:ethyl acetate = 5:1, v / v) to obtain 122 mg of a bright yellow solid in a 96% yield.

[0065] 1 H NMR (400MHz, CDCl3) δ = 8.41-8.36 (m, 2H), 7.94-7.91 (m, 2H), 7.30 (s, 1H), 4.19 (s, 3H).

[0066] (2) Preparation of Compound 2

[0067] The reaction route is as follows:

[0068]

[0069] Under argon, 3-bromo-2-methyl-5-phenylthiophene (0.20 g, 0.79 mmol) and anhydrous tetrahydrofuran (10 mL) were added to a reaction flask. The flask was cooled to -78°C, at which point the system turned orange-yellow. After stirring for 30 minutes, 1.6 mol / L n-butyllithium in n-hexane (0.50 mL, 0.8 mmol) was added dropwise (at a rate of 1 drop / s). The reaction was incubated at -78°C for 1 hour. Isopropyl pinacol borate (0.17 mL, 0.83 mmol) was then added. The reaction was continued at -78°C for 15 minutes, then warmed to room temperature and stirred at room temperature for 12 hours. After completion of the reaction (TLC monitoring of reaction progress), 10 mL of saturated brine was added to the resulting reaction solution. The mixture was extracted twice with ethyl acetate (25 mL x 2). The organic phases were combined and the solvent was removed by rotary evaporation to obtain the crude product as a pale yellow oily liquid. Column chromatography (eluent: petroleum ether: ethyl acetate = 20:1, v / v) was used for separation and purification to obtain 0.23 g of a light yellow oily liquid, 97.0%.

[0070] 1H NMR (400MHz, CDCl3) δ=7.58-7.55(m,2H),7.43(s,1H),7.35-7.31(m,2H),7.24-7.20(m,1H),2.70(s,3H),1.34(s,12H).

[0071] (3) Preparation of diarylethene compound I-1

[0072] The reaction route is as follows:

[0073]

[0074] Under nitrogen, compound 1 (0.10 g, 0.27 mmol), compound 2 (0.20 g, 0.67 mmol), tetrakis(triphenylphosphine)palladium (79 mg, 0.067 mmol), anhydrous sodium carbonate (1.2 g, 11 mmol), anhydrous tetrahydrofuran (5.4 mL), and distilled water (5.4 mL) were added sequentially to a Schlenk reaction flask and stirred until uniform. The system was transferred to a 100°C oil bath and refluxed for 24 hours. After completion of the reaction (TLC was used to monitor the reaction progress), the resulting reaction solution was washed with 5 mL of water and extracted twice with ethyl acetate (20 mL x 2). The organic phases were combined and the solvent was removed by rotary evaporation to obtain a crude brown solid product. Column chromatography was used with 200-300 mesh silica gel as filler and petroleum ether:ethyl acetate = 5:1 (v / v) as eluent for separation and purification. Finally, 0.12 g of an orange-yellow solid was obtained with a yield of 79.5%. The obtained compound was recorded as I-1.

[0075] 1 H NMR (400MHz, CDCl3) δ = 8.88 (s, 1H), 8.09 (s, 1H), 8.07 (s, 1H), 8.00 (s, 1H), 7.98 (s, 1H), 7.72 (d, J = 7.28Hz ,5H),7.59(d,J=7.80,4H),6.82(s,1H),6.53(s,1H),6.46(s,1H),4.05(s,3H),2.34(s,3H),2.30(s,3H).

[0076] 13C NMR (100MHz, CDCl3)δ=154.04,143.71,143.51,141.79,140.37,139.10,138.80,138.26,137.67,136.25,136.16,135.11,134.74,134.43 ,130.61,130.49,130.39,130.02,128.99,128.86,127.96,127.40,1 26.91,126.88,125.76,125.72,125.58,109.93,56.71,15.07,14.48.

[0077] HR-ESI-MS(m / z):calcd for[M] + C 35 H 26 N2OS2 + :554.1487;found:554.1565.

[0078] Example 2

[0079] A method for preparing a photochromic diarylethene compound with full visible light response comprises the following steps:

[0080] (1) The preparation of compound 1 is the same as that of Example 1.

[0081] (2) Preparation of Compound 3

[0082] The reaction route is as follows:

[0083]

[0084] Under nitrogen, 3-bromo-2-methyl-5-phenylthiazole (1.2 g, 4.7 mmol) and anhydrous tetrahydrofuran (45 mL) were added to a reaction flask. The flask was then placed at -78°C for 30 minutes. A 1.6 mol / L solution of n-butyllithium in n-hexane (3.3 mL, 5.2 mmol) was added dropwise (at a rate of 1 drop / s) to the reaction system, and the reaction was incubated at -78°C for 1 hour. Isopropyl pinacol borate (1.9 mL, 9.3 mmol) was added to the reaction flask, and the reaction was incubated at -78°C for 15 minutes. The mixture was then warmed to room temperature and stirred for 12 hours. After completion of the reaction (TLC monitoring of reaction progress), 10 mL of saturated brine was added to the resulting solution, and the mixture was extracted twice with ethyl acetate (25 mL x 2). The organic phases were combined and the solvent was removed by rotary evaporation to obtain the crude product. Column chromatography was used with 200-300 mesh silica gel as filler and petroleum ether / ethyl acetate = 5:1 (v / v) as eluent for separation and purification, and finally 1.3 g of a yellow oily liquid was obtained with a yield of 91.5%.

[0085] 1 H NMR (400MHz, CDCl3) δ7.98-7.92(m,2H),7.41-7.35(m,3H),2.74(s,3H),1.38(s,12H).

[0086] (3) Preparation of diarylethene compound I-2

[0087] The reaction route is as follows:

[0088]

[0089] Under nitrogen, compound 1 (0.1 g, 0.27 mmol), reactant 3 (0.20 g, 0.67 mmol), tetrakis(triphenylphosphine)palladium (79 mg, 0.067 mmol), anhydrous sodium carbonate (1.2 g, 11 mmol), 1,4-dioxane (5.4 mL), and distilled water (5.4 mL) were mixed and reacted in an oil bath at 100°C for 24 hours. After completion of the reaction (TLC was used to monitor the reaction progress), the resulting solution was washed with 10 mL of water and extracted twice with ethyl acetate (20 mL x 2). The organic phases were combined and the solvent was removed by rotary evaporation to obtain a crude brown solid. The crude product was separated and purified by column chromatography (eluent: petroleum ether, packing: 200-300 mesh silica gel) to obtain 87 mg of a pink solid with a yield of 57.88%. The resulting compound was designated I-2.

[0090] 1H NMR (400MHz, CDCl3) δ8.42(d,J=8.6Hz,1H),8.17(d,J=8.24Hz,1H),7.97-7.90(m,2H),7.87 -7.76(m,4H),7.45-7.39(m,3H),7.37-7.30(m,4H),4.27(s,3H),2.20(s,3H),2.18(s,3H).

[0091] 13 C NMR (100MHz, CDCl3) δ167.86,164.42,163.08,154.95,151.54,148.74,143.87,143.72,142.00,138.32,136.58,134.29,133.84,132.43,132 .39,131.19,131.05,130.64,130.62,130.37,130.05,129.86,129.39, 129.00,128.97,128.82,126.46,126.19,109.44,56.82,12.86,12.41.

[0092] HR-ESI-MS m / z:calcd for [M+H] + C 33 H 24 N4OS2 + :557.1470;found:557.1483.

[0093] Experimental Example 1

[0094] Weigh different masses of I-1 into 10 mL volumetric flasks and dilute to volume with chromatographic methanol to obtain five bottles of sample solutions with different concentrations. The concentrations of the sample solutions are 1.745×10 -3 mol / L, 8.727×10 -4 mol / L, 4.364×10 - 4 mol / L, 2.182×10 -4 mol / L, 1.091×10 -4 mol / L, the UV-visible absorption spectra of the above five different concentrations of I-1 sample solutions were measured using a UV-visible spectrophotometer, and the results were as follows Figure 1 As shown, it can be concluded that I-1 is an open-ring isomer at this time, and the maximum absorption wavelength λ is 288 nm. Regression analysis of the maximum absorption wavelength shows that the absorbance of compound I-1 at the same wavelength is positively correlated with its corresponding concentration, which conforms to the Lambert-Beer law.

[0095] I-1 was dissolved in chromatographic methanol solution (concentration 4.364×10 -4 mol / L) and irradiated under 430nm ultraviolet light. The UV-visible absorption spectra at different irradiation times are shown in Figure 2. Figure 2 As shown. Figure 2 It can be seen that with the increase of illumination time, the absorption intensity at the maximum absorption wavelength of I-1 gradually increases, while the absorption intensity at 337nm and 375nm gradually increases, and its isosbestic point is at 300nm, which confirms the existence of two isomers in the system, namely open-ring isomers and closed-ring isomers.

[0096] Weigh different masses of I-1 into 10 mL volumetric flasks and dilute to volume with chromatographic acetonitrile to obtain five bottles of sample solutions with different concentrations. The concentrations of the sample solutions are 2.885×10 -4 mol / L, 1.442×10 -4 mol / L, 7.214×10 - 5 mol / L, 3.606×10 -5 mol / L, 1.803×10 -5 mol / L. The UV-visible absorption spectra of the above five different concentrations of I-1 sample solutions were measured using a UV-visible spectrophotometer. The results are as follows Figure 3 As shown, it can be concluded that I-1 is an open-ring isomer at this time, and the maximum absorption wavelength λ is 287 nm. Regression analysis of the maximum absorption wavelength shows that the absorbance of compound I-1 at the same wavelength is positively correlated with its corresponding concentration, which conforms to the Lambert-Beer law.

[0097] I-1 was dissolved in chromatographic acetonitrile solution (concentration 2.025×10 -4 mol / L) and irradiated under 430nm ultraviolet light. The UV-visible absorption spectra at different irradiation times are shown in Figure 2. Figure 4 As shown, from Figure 4 It can be seen that with the increase of illumination time, the absorption intensity at the maximum absorption wavelength of I-1 gradually decreases, while the absorption intensity at 350nm, 425nm and 550nm gradually increases, and its isosbestic point is at 305nm, which confirms the existence of two isomers in the system, namely open-ring isomers and closed-ring isomers.

[0098] Weigh different masses of I-1 into 10 mL volumetric flasks and dilute to volume with chromatographic n-hexane to obtain five bottles of sample solutions with different concentrations. The concentrations of the sample solutions are 1.083×10 -4 mol / L, 5.415×10 -5 mol / L, 2.708×10 -5mol / L, 1.354×10 -5 mol / L, 6.768×10 -6 mol / L. The UV-visible absorption spectra of the above five different concentrations of I-1 sample solutions were measured using a UV-visible spectrophotometer. The results are as follows Figure 5 As shown, it can be concluded that I-1 is an open-ring isomer at this time, and the maximum absorption wavelength λ is 288 nm. Regression analysis of the maximum absorption wavelength shows that the absorbance of compound I-1 at the same wavelength is positively correlated with its corresponding concentration, which conforms to the Lambert-Beer law.

[0099] I-1 was dissolved in chromatographic n-hexane solution (concentration 8.11×10 -5 mol / L) and irradiated under 430nm ultraviolet light. The UV-visible absorption spectra at different irradiation times are shown in Figure 2. Figure 6 As shown, from Figure 6 It can be seen that with the increase of illumination time, the absorption intensity at the maximum absorption wavelength of I-1 gradually decreases, while the absorption intensity at 380nm, 420nm and 550nm gradually increases, and its isosbestic point is at 305nm, which confirms the existence of two isomers in the system, namely open-ring isomers and closed-ring isomers.

[0100] The above experiments show that before illumination, the maximum absorption wavelength of the I-1 open-ring isomer in different chromatographically pure solutions is approximately 288 nm, and it has a certain absorption intensity in the visible light region (400-500 nm), thereby enabling a visible light-induced photocyclization reaction, at which point the solution color is yellow. The reason for the significant change in the UV-visible absorption spectrum of I-1 is that its open-ring isomer undergoes a photoisomerization reaction under 430 nm illumination conditions, generating a closed-ring isomer from the open-ring isomer. At this point, its absorption spectrum has significant absorption at 500-800 nm, and after being illuminated by visible light >520 nm, the absorption spectrum of the compound changes back to its original state, i.e., the compound generates an open-ring isomer from the closed-ring isomer. The above experimental tests show that I-1 can achieve a photoisomerization reaction initiated by all visible light.

[0101] Similarly, I-2 also underwent the same photoisomerization reaction as I-1 under light conditions ( Figure 7 This is a UV-visible absorption spectrum of the diarylethene compound prepared in Example 2 at different concentrations in chromatographic methanol; Figure 8 The diarylethene compound prepared in Example 2 was chromatographed in methanol (concentration of 6.30×10 -5 mol / L) under different irradiation times; Figure 9The UV-visible absorption spectra of the diarylethene compound prepared in Example 2 at different concentrations in chromatographic acetonitrile are shown; Figure 10 The diarylethene compound prepared in Example 2 was chromatographed in acetonitrile (concentration of 2.70×10 - 5 mol / L) under different irradiation times; Figure 11 The UV-visible absorption spectra of the diarylethene compound prepared in Example 2 at different concentrations in chromatographic n-hexane are shown; Figure 12 The diarylethene compound prepared in Example 2 was chromatographed in n-hexane (concentration of 4.05×10 -5 mol / L) under different irradiation times.

[0102] At the same time, to further investigate the photochromic properties of I-1 and I-2, compounds I-1 and I-2 were drop-cast onto glass slides with a chloroform solution of PMMA (polymethyl methacrylate) (10 wt%) (the compound weight being 5% of the PMMA weight) and dried to produce clear, colorless films. To explore the solid-state photochemical properties of the target compounds, I-1 and I-2 were dissolved in a chloroform solution (12 mmol / L) and then coated onto glass slides and dried. The photochromic behavior of these films and solids under UV irradiation was tested using a UV-visible spectrophotometer. UV-visible absorption spectra revealed no significant changes in the UV-visible absorption spectra or color of I-1 and I-2 in PMMA films and solids, regardless of whether irradiation was visible or UV. This finding likely stems from the target compounds being in a parallel conformation in the solid state, which prevents photoisomerization.

[0103] Experimental Example 2

[0104] The target compound I-1 was dissolved in chromatographic n-hexane solution (8.11×10 -5 mol / L) as an example. As the illumination time increases, the fluorescence intensity of compound I-1 at the maximum emission wavelength gradually decreases under the excitation of light with a wavelength of 285 nm, while the fluorescence intensity at 340 nm-400 nm gradually increases ( Figure 13 ), which shows that compound I-1 behaves as a "turn-off" type fluorescent molecular switch.

[0105] Compound I-2 was dissolved in chromatographic n-hexane solution (concentration of 4.045×10 -5 mol / L), and showed similar fluorescence properties to I-1 ( Figure 14 ).

[0106] Experimental Example 3

[0107] In the chromatographic n-hexane solution, compound I-1 (concentration of 8.11×10 -5 mol / L) and I-2 (concentration of 4.05×10 -5 mol / L) under continuous alternating irradiation of ultraviolet light (254nm) and visible light (>520nm), by detecting the absorbance at the maximum absorption wavelength of the two compounds, it can be seen that the absorption intensity at the maximum absorption wavelength of the closed-ring isomer of compound I-1 does not show significant decay with alternating irradiation, which confirms that compound I-1 does not undergo significant decomposition or irreversible changes during the repeated photoisomerization process ( Figure 15 ); In contrast, the absorbance intensity at the maximum absorption wavelength of the closed-ring isomer of compound I-2 shows a decreasing trend with alternating light exposure, confirming that the fatigue resistance of compound I-2 is worse than that of I-1, and a certain degree of decomposition or irreversible change may have occurred during this process ( Figure 16 ).

[0108] Experimental Example 4

[0109] In the thermal reverse reaction test of the target compound, compound I-1 was dissolved in anhydrous toluene solution (concentration of 8.50×10 -5 mol / L) was irradiated with 430nm ultraviolet light to generate the corresponding closed-ring isomers. A series of temperature gradients (30-80℃) were set up, and the thermal reverse reaction properties of the closed-ring isomers at the characteristic absorption peak of 559nm at different temperatures were investigated under light-proof conditions. The first-order function graph and Arrhenius graph were drawn based on the characteristic absorption peak absorbance and time change curve. Through calculation, it was found that the absorption intensity at the characteristic absorption peak of I-1 closed-ring isomer gradually decreased under different temperature environments ( Figure 17 and 18 ), and with the increase of temperature gradient, the rate of decrease of absorption intensity of I-1 closed-ring isomer at characteristic absorption peak gradually accelerated. Under the same conditions, compound I-2 (concentration of 4.25×10 -5 mol / L) showed similar thermally induced reverse reaction properties ( Figure 19 and 20 ). This confirms that both compounds exhibit faster thermally induced reverse reaction rates.

[0110] It can be seen from the above embodiments that the present invention provides a diarylethene photochromic compound with full visible light responsiveness. The photochromic compound prepared according to the method of the present invention has the following advantages: a short synthesis route, a simple synthesis method, cheap raw materials required, and strong operability; it has the photochromic properties and stability of traditional diarylethene compounds; it has visible light photosensitivity and fluorescence characteristics, which can broaden the scope of photochemical applications of diarylethene photochromic compounds. The diarylethene compound provided by the present invention is different from the traditional diarylethene photochromic compounds. The most stable ultraviolet-visible absorption wavelength of the open-ring isomer of the target diarylethene photochromic compound mentioned in the present invention can be extended to 500nm, so that it has a visible light responsive photoisomerization reaction. At the same time, the unique fluorescence properties of the target photochromic compound and the change in fluorescence intensity induced by photoisomerization make it have important research significance in the fields of fluorescence site tracking and fluorescent labeling.

[0111] Experimental Example 5

[0112] Cell imaging test of the target compounds: Compounds I-1 and I-2 were cultured with A549 cells in aqueous solutions containing 5% dimethyl sulfoxide (concentration: 20.0 μmol / L) for 60 minutes. Both compounds showed good fluorescence imaging properties in the cells under confocal microscopy ( Figure 21 and Figure 22 ), thus confirming that the above two compounds can be used in the field of cell fluorescence imaging.

[0113] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0114] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A photochromic diarylethene compound with full visible light response, characterized in that: It has the structure shown in the following formula I: In formula I, Ar1 and Ar2 groups are independently selected from 2-methyl-5-phenyl-thiophene and 5-methyl-2-phenyl-thiazole.

2. The photochromic diarylethene compound with full visible light response according to claim 1, characterized in that: The fully visible light responsive photochromic diarylethene compound is selected from one of the following compounds:

3. The photochromic diarylethene compound with full visible light response according to claim 1, characterized in that: The preparation method of the above-mentioned photochromic diarylethene compound with full visible light response comprises the following steps: 1,2-dibromo-4-methoxyphenazine, a borate compound, a catalyst, an alkaline substance, water and an organic solvent are uniformly mixed and subjected to a coupling reaction to obtain a photochromic diarylethene compound with full visible light response.

4. The method for preparing the photochromic diarylethene compound with full visible light response according to claim 3, characterized in that: The borate compound comprises one or more of 2-methyl-5-phenyl-thiophene borate and 5-methyl-2-phenyl-thiazole borate; the structural formula of the 2-methyl-5-phenyl-thiophene borate is shown in Formula III below, and the structural formula of the 5-methyl-2-phenyl-thiazole borate is shown in Formula IV below; 5. The method for preparing the photochromic diarylethene compound with full visible light response according to claim 3, characterized in that: The molar ratio of the 1,2-dibromo-4-methoxyphenazine to the borate ester compound is 1-3:2-7, preferably 1.5-2.5:4-6, and more preferably 2:

5.

6. The method for preparing the photochromic diarylethene compound with full visible light response according to claim 3, characterized in that: The catalyst is tetrakis(triphenylphosphine)palladium, palladium acetate or bis(diphenylphosphino)ferrocenepalladium dichloride; the molar ratio of the catalyst to 1,2-dibromo-4-methoxyphenazine is 0.1-1:1-3, preferably 0.2-0.8:1.5-2.5, more preferably 0.5:2; The alkaline substance is one or more of sodium carbonate, tripotassium phosphate and cesium carbonate; the molar ratio of the alkaline substance to 1,2-dibromo-4-methoxyphenazine is 40-100:1-3, preferably 60-90:1.5-2.5, and more preferably 80:

2.

7. The method for preparing the photochromic diarylethene compound with full visible light response according to claim 3, characterized in that: The ratio of the volume of water to the molar number of 1,2-dibromo-4-methoxyphenazine is 20-50 L:1-3 mol, preferably 35-45 L:1.5-2.5 mol, and more preferably 40 L:2 mol; The organic solvent is tetrahydrofuran and / or 1,4-dioxane; the ratio of the volume of the organic solvent to the molar number of 1,2-dibromo-4-methoxyphenazine is 20-50 L:1-3 mol, preferably 35-45 L:1.5-2.5 mol, and more preferably 40 L:2 mol.

8. The method for preparing the photochromic diarylethene compound with full visible light response according to claim 3, characterized in that: The coupling reaction temperature is 70-110° C.; the coupling reaction time is 12-48 hours; the coupling reaction is carried out under a protective gas atmosphere, and the protective gas is one or more of a rare gas and nitrogen.

9. The method for preparing the photochromic diarylethene compound with full visible light response according to claim 3, characterized in that: The specific post-reaction treatment steps are as follows: adding water to the reaction solution obtained by the coupling reaction for washing, then extracting with ethyl acetate 2 to 5 times, combining the organic phases, removing the solvent from the obtained organic phases to obtain a crude product, and separating and purifying the obtained crude product by column chromatography, wherein the eluent used for the column chromatography is petroleum ether, n-hexane, a petroleum ether-ethyl acetate mixed solvent or a n-hexane-ethyl acetate mixed solvent, the volume ratio of petroleum ether to ethyl acetate in the petroleum ether-ethyl acetate mixed solvent is 2 to 50:1, and the volume ratio of n-hexane to ethyl acetate in the n-hexane-ethyl acetate mixed solvent is 2 to 50:1; the mesh number of the silica gel used for the column chromatography is 200 to 300 mesh, or 300 to 400 mesh.

10. Use of the photochromic diarylethene compound with full visible light response according to claim 1 or 2 in cell fluorescence imaging, information storage, anti-counterfeiting components and photosensitive liquid crystal materials.

Images