A photochromic diarylethene compound, a preparation method thereof and an application thereof

Abstract

The present invention belongs to the technical field of photochromic compounds, and specifically discloses a photochromic diarylethene compound, a preparation method thereof and an application thereof. In the present invention, 2,3-dibromo-1,1-dimethyl-1H-indene is subjected to a coupling reaction with a borate compound to obtain a diarylethene compound; the borate compound includes one or more of 2-methyl-5-phenyl-thiophene borate, 5-methyl-2-phenyl-thiazole borate and 2-methylnaphthalene borate. The present invention provides a diarylethene photochromic compound with an indene as an alkene bridge, which can undergo a reversible change between open and closed ring isomers under the condition of illumination with a specific wavelength, and the properties such as the color and absorption spectrum of the compound will also undergo a reversible change. The present invention also provides a preparation method for such compounds, which has the advantages of simple preparation method, high product safety, low raw material cost, easy separation of products and easy realization of industrial synthesis.

Description

Technical Field

[0001] The present invention relates to the technical field of photochromic compounds, and particularly to a photochromic diarylethene compound, a preparation method thereof, and an application thereof. Background Art

[0002] In recent years, with the continuous development of modern industrial chemistry, more and more scientific and technological products with excellent performance have entered people's daily lives. Among them, optical switch materials have been explored and exploited due to their excellent chemical properties and broad application prospects.

[0003] Due to the unique reversible photocyclization reaction of diarylethene photochromic compounds and the excellent thermal stability of the open and closed ring isomers, they can exhibit excellent data transmission capabilities and strong anti-fatigue properties in different media and states. These characteristics make them stand out among many photochromic materials. Currently, the most classic diarylethene photochromic compound uses perfluorocyclopentene as the alkene bridge, but due to its high price and strong toxicity, its application scope in photochemistry is restricted.

[0004] Therefore, how to provide a photochromic diarylethene compound, a preparation method thereof, and an application thereof, to improve the safety of the photochromic compound and reduce the preparation cost is an urgent problem to be solved in this field. Summary of the Invention

[0005] In view of this, the present invention provides a photochromic diarylethene compound, a preparation method thereof, and an application thereof, to solve the problem that the existing photochromic compounds are restricted in their application in the field of photochemistry due to their high price and strong toxicity.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A photochromic diarylethene compound, the structure of the diarylethene compound is as follows:

[0008]

[0009] Wherein, Ar 1 and Ar 2 groups are independently one or more of 2-methyl-5-phenyl-thiophene, 5-methyl-2-phenyl-thiazole, and 2-methylnaphthalene.

[0010] Another object of the present invention is to provide a preparation method of a photochromic diarylethene compound, the preparation method comprising the following steps:

[0011] Couple 2,3-dibromo-1,1-dimethyl-1H-indene with a borate compound to obtain a diarylethene compound;

[0012] The borate compound includes one or more of 2-methyl-5-phenyl-thiophene borate, 5-methyl-2-phenyl-thiazole borate, and 2-methylnaphthalene borate.

[0013] Preferably, the molar ratio of 2,3-dibromo-1,1-dimethyl-1H-indene to the borate compound is 1-3:2-7.

[0014] Preferably, the temperature of the coupling reaction is 70-110 °C, and the time of the coupling reaction is 12-48 h.

[0015] Preferably, the coupling reaction is carried out under catalyst conditions;

[0016] The catalyst includes tetrakis(triphenylphosphine)palladium, palladium acetate, and dichlorobis(diphenylphosphino)ferrocene palladium.

[0017] Preferably, the preparation method of the diarylethene compound is as follows:

[0018] Mix 2,3-dibromo-1,1-dimethyl-1H-indene, the borate compound, the catalyst, the basic substance, water, and the organic solvent, and carry out a coupling reaction to obtain the diarylethene compound.

[0019] Preferably, the molar volume ratio of 2,3-dibromo-1,1-dimethyl-1H-indene, the borate compound, the catalyst, the basic substance, water, and the organic solvent is 1-3 mol:2-7 mol:0.1-1 mol:40-70 mol:20-40 L:20-40 L.

[0020] Preferably, the borate compound is one or several of

[0021] Preferably, the basic substance includes one or several of sodium carbonate, tripotassium nitrate, and potassium phosphate;

[0022] The organic solvent includes tetrahydrofuran and / or 1,4-dioxane.

[0023] Another object of the present invention is to provide an application of the diarylethene compound prepared by the preparation method in the fields of medicine, information storage, anti-counterfeiting components, and photosensitive liquid crystal materials.

[0024] Through the above technical solutions, compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention provides a diarylethene compound with photoreactivity. The present invention provides a diarylethene photochromic compound with indene as the bridging olefin, which can undergo a light-induced change in molecular structure under the irradiation of visible light and ultraviolet light. During this process, the diarylethene compound has a significant color change and a significant absorption in the visible light region.

[0026] The present invention also provides a preparation method of a diarylethene compound with photoreactivity. Based on the diarylethene structure, a novel photochromic diarylethene compound with photoisomerization reaction is obtained through the Suzuki-Miyaura coupling reaction. Its synthesis steps are 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.

[0027] The photochromic diarylethene compound with indene as the structural basis prepared by the present invention has the characteristics of simple structure, small space occupation and short synthesis cycle, and is easier to achieve chemical modification compared with the diarylethene compound with perfluorocyclopentane as the bridging olefin. Description of the Drawings

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0029] Figure 1 It is the ultraviolet-visible absorption spectrum diagram of the diarylethene compound in Example 1 at different concentrations in chromatographic methanol;

[0030] Figure 2 It is the ultraviolet-visible absorption spectrum diagram of the diarylethene compound in Example 1 at different irradiation times in chromatographic methanol;

[0031] Figure 3 It is the ultraviolet-visible absorption spectrum diagram of the diarylethene compound in Example 1 at different concentrations in chromatographic acetonitrile;

[0032] Figure 4 It is the ultraviolet-visible absorption spectrum diagram of the diarylethene compound in Example 1 at different irradiation times in chromatographic acetonitrile;

[0033] Figure 5 It is the ultraviolet-visible absorption spectrum diagram of the diarylethene compound in Example 1 at different concentrations in chromatographic n-hexane;

[0034] Figure 6It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 1 under different irradiation times in n-hexane for chromatography.

[0035] Figure 7 It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 2 at different concentrations in methanol for chromatography;

[0036] Figure 8 It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 2 under different irradiation times in methanol for chromatography;

[0037] Figure 9 It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 2 at different concentrations in acetonitrile for chromatography;

[0038] Figure 10 It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 2 under different irradiation times in acetonitrile for chromatography;

[0039] Figure 11 It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 2 at different concentrations in n-hexane for chromatography;

[0040] Figure 12 It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 2 under different irradiation times in n-hexane for chromatography.

[0041] Figure 13 It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 3 at different concentrations in methanol for chromatography;

[0042] Figure 14 It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 3 under different irradiation times in methanol for chromatography;

[0043] Figure 15 It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 3 at different concentrations in acetonitrile for chromatography;

[0044] Figure 16 It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 3 under different irradiation times in acetonitrile for chromatography;

[0045] Figure 17 It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 3 at different concentrations in n-hexane for chromatography;

[0046] Figure 18 It is the UV-Vis absorption spectrogram of the diarylethene compound in Example 3 under different irradiation times in n-hexane for chromatography;

[0047] Among them,Figures 1 - 18 Among them, Absorbance - absorbance, Wavelength - wavelength. Detailed implementation manners

[0048] The present invention provides a photochromic diarylethene compound, and the structure of the diarylethene compound is as follows:

[0049]

[0050] Wherein, Ar 1 and Ar 2 groups are independently one or more of 2 - methyl - 5 - phenyl - thiophene, 5 - methyl - 2 - phenyl - thiazole, and 2 - methylnaphthalene.

[0051] The present invention also provides a preparation method of a photochromic diarylethene compound, and the preparation method includes the following steps:

[0052] Carry out a coupling reaction between 2,3 - dibromo - 1,1 - dimethyl - 1H - indene and a borate compound to obtain a diarylethene compound;

[0053] The borate compound includes one or more of 2 - methyl - 5 - phenyl - thiophene borate, 5 - methyl - 2 - phenyl - thiazole borate, and 2 - methylnaphthalene borate.

[0054] In the present invention, the molar ratio of 2,3 - dibromo - 1,1 - dimethyl - 1H - indene to the borate compound is 1 - 3:2 - 7, preferably 1.5 - 2.5:4 - 6, and more preferably 2:5.

[0055] In the present invention, the temperature of the coupling reaction is 70 - 110 °C, specifically it can be 75 °C, 80 °C, 85 °C, 90 °C, 95 °C, 100 °C; the time of the coupling reaction is 12 - 48 h, specifically it can be 15 h, 18 h, 20 h, 24 h, 30 h, 35 h, 36 h, 40 h, 45 h.

[0056] In the present invention, the coupling reaction is carried out under catalyst conditions.

[0057] In the present invention, the catalyst includes tetrakis(triphenylphosphine)palladium, palladium acetate, and dichlorobis(diphenylphosphino)ferrocene palladium.

[0058] In the present invention, the preparation method of the diarylethene compound is as follows:

[0059] Mix 2,3 - dibromo - 1,1 - dimethyl - 1H - indene, a borate compound, a catalyst, a basic substance, water, and an organic solvent, and carry out a coupling reaction to obtain a diarylethene compound.

[0060] In the present invention, the molar volume ratio of the 2,3-dibromo-1,1-dimethyl-1H-indene, borate compound, catalyst, basic substance, water and organic solvent is 1-3 mol: 2-7 mol: 0.1-1 mol: 40-70 mol: 20-40 L: 20-40 L, preferably 1.5-2.5 mol: 4-6 mol: 0.2-0.8 mol: 50-60 mol: 25-35 L: 25-35 L, and further preferably 2 mol: 5 mol: 0.5 mol: 55 mol: 30 L: 30 L.

[0061] In the present invention, the borate compound is one or more of

[0062] In the present invention, the basic substance includes one or more of sodium carbonate, tripotassium nitrate and potassium phosphate.

[0063] In the present invention, the organic solvent includes tetrahydrofuran and / or 1,4-dioxane.

[0064] In the present invention, the coupling reaction is preferably carried out under an inert atmosphere, specifically one or more of a rare gas atmosphere and a nitrogen atmosphere.

[0065] In the present invention, after the coupling reaction ends, it also includes the steps of post-treatment, and the post-treatment is washing, extraction, concentration, drying and purification carried out in sequence.

[0066] In the present invention, the detergent is preferably water, the extractant is preferably ethyl acetate, the number of extractions is preferably greater than or equal to 2 times, further preferably greater than or equal to 3 times, and more preferably 4 times; the instrument used for concentration is preferably a rotary evaporator.

[0067] In the present invention, the purification is preferably column chromatography purification, the silica gel mesh number of the chromatographic column is preferably 200-300 mesh, and can also be 300-400 mesh; the eluent in the process of column chromatography purification is preferably petroleum ether.

[0068] The present invention also provides an application of the diarylethene compound prepared by the preparation method in the fields of medicine, information storage, anti-counterfeiting components and photosensitive liquid crystal materials.

[0069] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0070] The preparation methods of Compounds 1-4 in Embodiments 1-3 of the present invention do not limit the solution of the present invention.

[0071] Example 1

[0072]

[0073] Compound 1: (E)-3,4-Dibromo-2-methyl-4-phenylbut-3-en-2-ol (50 mg, 0.156 mmol), dichloromethane (2.00 mL), and boron trifluoride ethyl etherate (0.060 mL, 0.469 mmol) were added to a reaction flask, and the reaction flask was placed at room temperature for 15 minutes. After the reaction was completed (monitored by TLC), an appropriate amount of methanol was added to the reaction system, and the mixture was extracted twice with dichloromethane. The organic phases were combined and concentrated using a rotary evaporator to obtain a crude product as a yellow oily liquid (2,3-dibromo-1,1-dimethyl-1H-indene). Through column chromatography (silica gel: 200-300 mesh, eluent: petroleum ether), a white solid was obtained with a yield of 68%.

[0074] 1 H NMR (400 MHz, CDCl 3 ) δ: 1.32 (s, 6H), 7.2 - 7.4 (m, 4H).

[0075]

[0076] Compound 2: Under argon protection, 3-bromo-2-methyl-5-phenylthiophene (0.20 g, 0.781 mmol) and anhydrous tetrahydrofuran (10 mL) were added to a reaction flask, and the reaction flask was cooled to -78 °C in a constant-temperature low-temperature reaction bath. n-BuLi (0.50 mL, 0.80 mmol, 1.6 mol / L in hexane) was slowly added dropwise to the reaction flask. After reacting for one hour, isopropyl alcohol pinacol borate (0.20 mL, 0.862 mmol) was added. After reacting for 15 minutes, the reaction flask was taken out of the constant-temperature low-temperature reaction bath and reacted overnight under stirring at room temperature. After the reaction was completed (monitored by TLC), an appropriate amount of saturated brine was added to the reaction system, and the mixture was extracted twice with ethyl acetate. The organic phases were combined and concentrated using a rotary evaporator to obtain a crude product as a yellow oily liquid. The above crude product was separated and purified by column chromatography (silica gel: 200-300 mesh, eluent: petroleum ether: ethyl acetate = 20:1) to obtain 0.27 g of a pale yellow solid with a yield of 96%.

[0077] 1 H NMR (500 MHz, CDCl 3) δ: 7.56 - 7.58 (2H, m), 7.43 (1H, s), 7.32 - 7.36 (2H, t, J = 8.0 MHz), 7.21 - 7.24 (1H, t, J = 7.5 MHz), 2.70 (3H, s), 1.34 (12H, s).

[0078]

[0079] DAE-1 (Diaryl Ethylene Compound): Under argon, reactant 1 (2,3-dibromo-1,1-dimethyl-1H-indene) (50.0 mg, 0.166 mmol), reactant 2 (0.12 g, 0.414 mmol), tetrakis(triphenylphosphine)palladium (48.0 mg, 0.041 mmol), sodium carbonate (0.66 g, 6.62 mmol), 1,4-dioxane (3.0 mL, 3.31 mmol), distilled water (3.5 mL) were mixed and then reacted in an oil bath at 100 °C for 48 hours. After the reaction (monitored by TLC), water was added to the reaction system for washing, and extraction was carried out twice with ethyl acetate. The organic phases were combined and concentrated using a rotary evaporator to obtain a brown solid crude product. The above crude product was separated and purified by column chromatography (silica gel: 200 - 300 mesh, eluent: petroleum ether) to obtain 50 mg of a purple solid with a yield of 71%. The obtained compound was designated as DAE-1.

[0080] 1 H NMR (400 MHz, CDCl 3 ) δ: 1.96 (s, 6H), 2.08 (s, 6H), 7.45 (m, 2H), 7.52 (d, 4H, J = 8 Hz), 7.58 (d, 4H, J = 8 Hz).

[0081] 13 C NMR (400 MHz, CDCl 3 ) δ 153.39, 149.41, 142.72, 140.21, 140.07, 136.88, 136.28, 134.76, 134.60, 134.58, 133.92, 133.02, 128.96, 128.92, 127.19, 127.12, 126.77, 125.64, 125.48, 125.43, 124.53, 123.68, 121.57, 120.93, 51.79, 24.89, 21.12, 14.77, 14.29.

[0082] HR-MS m / z: calcd for [M] + C 33 H29 S 2 + :Called for 489.1704; found: 489.1711.

[0083] The structural formula of DAE-1:

[0084] Example 2

[0085]

[0086] Compound 3: Under the protection of argon, 4-bromo-5-methyl-2-phenylthiazole (1.00 g, 3.93 mmol) and anhydrous tetrahydrofuran (20 mL) were added to the reaction flask, and the reaction flask was cooled to -78 °C in a constant-temperature low-temperature reaction bath. n-Butyllithium (5.0 mL, 8.00 mmol, 1.6 mol / L in hexane) was slowly added dropwise to the reaction flask. After reacting for one hour, isopropyl alcohol pinacol borate (1.70 mL, 7.86 mmol) was added. After reacting for 60 minutes, the reaction flask was taken out of the constant-temperature low-temperature reaction bath and reacted overnight under stirring at room temperature. After the reaction was completed (the progress of the reaction was detected by TLC), an appropriate amount of saturated brine was added to the reaction system, and the mixture was extracted twice with ethyl acetate. The organic phases were combined and concentrated using a rotary evaporator to obtain a crude product as a yellow oily liquid. The above crude product was separated and purified by column chromatography (silica gel: 200 - 300 mesh, eluent: petroleum ether: ethyl acetate = 20:1) to obtain 0.87 g of a pale yellow solid with a yield of 73.37%.

[0087] 1 H NMR (500 MHz, CDCl 3 ) δ: 1.38 (s, 12H), 2.74 (s, 3H), 7.37 - 7.42 (m, 3H), 7.94 - 7.97 (s, 1H).

[0088]

[0089] DAE-2 (diarylvinyl compound): Under the protection of argon, 2,3-dibromo-1,1-dimethyl-1H-indene (50.0 mg, 0.166 mmol), reactant 3 (124.7 mg, 0.414 mmol), palladium tetrakis(triphenylphosphine) (48.0 mg, 0.041 mmol), potassium phosphate (1.4 g, 6.62 mmol), 1,4-epoxyhexane (3.5 mL, 3.86 mmol), and distilled water (3.5 mL) were mixed and reacted in an oil bath at 100 °C for 24 hours. After the reaction was completed (the progress of the reaction was detected by TLC), water was added to the reaction system for washing, and extraction was carried out twice with ethyl acetate. The organic phases were combined and concentrated by a rotary evaporator to obtain a crude yellow solid product. The above crude product was separated and purified by column chromatography (silica gel: 200 - 300 mesh, eluent: petroleum ether) to obtain 48 mg of a pink oily solid with a yield of 59%. The obtained compound was designated as DAE-2.

[0090] 1 H NMR (400 MHz, CDCl 3 ) δ = δ 8.27–8.25 (m, 1H), 8.03 (dd, J = 9.52, 1.68 Hz, 2H), 7.97 (dd, J = 7.64, 1.4 Hz, 2H), 7.51–7.45 (m, 6H), 7.36–7.32 (m, 3H), 1.95 (d, J = 5.6 Hz, 6H), 1.76 (s, 3H), 1.59 (s, 3H).

[0091] 13 C NMR (400 MHz, CDCl 3 ) δ 164.51, 163.79, 163.39, 154.13, 148.79, 148.49, 147.71, 146.73, 142.21, 134.24, 134.07, 134.05, 133.49, 132.53, 132.07, 131.95, 129.76, 129.71, 129.67, 129.14, 129.00, 128.97, 128.30, 126.79, 126.49, 126.45, 126.34, 126.31, 126.07, 122.28, 121.36, 52.38, 25.11, 13.22, 12.44, 12.36. HR-MS m / z: calcd for [M] + C 31 H 26 N 2 S 2 + : cald for 491.1624; found: 491.1616.

[0092] Example 3

[0093]

[0094] Compound 4: Under the protection of argon, 1-bromo-2-methylnaphthalene (2.21 mL, 1.49 mL, 10.0 mmol) and anhydrous tetrahydrofuran (120 mL) were added to a reaction flask, and the reaction flask was placed in a low-temperature reactor at -78 °C. n-BuLi (6.9 mL, 11 mmol, 1.6 mol / L in hexane) was added dropwise with a syringe. After reacting for one hour, isopropyl alcohol pinacol borate (2.23 g, 2.45 mL, 12 mmol) was added to the system. After taking the reaction flask out of the low-temperature reactor, it was allowed to react at room temperature overnight. An appropriate amount of saturated brine was added to the reaction system, and the mixture was extracted twice with ethyl acetate. The organic phases were combined and concentrated with a rotary evaporator to obtain a crude product as a yellow oily liquid. The above crude product was separated and purified by column chromatography (silica gel: 200 - 300 mesh, eluent: petroleum ether:ethyl acetate = 20:1) to obtain 2.40 g of a pale yellow solid with a yield of 89.55%.

[0095] 1 H NMR(500MHz,CDCl 3 ): δ = 8.10 (1H, d, J = 8.5 Hz), 7.76 (2H, t, J = 6.5 Hz), 7.45 (1H, dt, J = 1.0 Hz, 8.0 Hz), 7.38 (1H, dt, J = 1.0 Hz, 8.0 Hz), 7.27 (1H, t, J = 8.5 Hz), 2.62 (3H, s), 1.49 (12H, s).

[0096]

[0097] DAE-3 (diarylethene compound): Under an argon atmosphere, 2,3-dibromo-1,1-dimethyl-1H-indene (100.0 mg, 0.331 mmol), Compound 4 (221.5 mg, 0.826 mmol), tetrakis(triphenylphosphine)palladium (96.0 mg, 0.082 mmol), potassium phosphate (2.8 g, 13.2 mmol), 1,4-dioxane (7.0 mL, 7.72 mmol), and distilled water (7.0 mL) were mixed and reacted in an oil bath at 100 °C for 24 hours. After the reaction was completed (monitored by TLC), water was added to the reaction system for washing, and the mixture was extracted twice with ethyl acetate. The organic phases were combined and concentrated with a rotary evaporator to obtain a crude product as a yellow solid. The above crude product was separated and purified by column chromatography (silica gel: 200 - 300 mesh, eluent: petroleum ether) to obtain 84 mg of a pale yellow solid with a yield of 60%. The resulting compound was designated as DAE-3.

[0098] 1 1H NMR(400MHz,CDCl 3 )δ=8.05(d,J=8.5Hz,1H),7.91(d,J=8.5Hz,1H),7.60–7.51(m,5H),7.31(t,J=7.4Hz,1H),7.21-7.16(m,5H),7.13-7.05(m,2H),6.82(d,J=7.5Hz,1H),2.43(s,3H),2.35(s,3H),1.53(s,3H),1.47(s,3H).

[0099] 13 13C NMR(400MHz,CDCl 3 )δ153.27,153.21,144.08,140.19,135.62,135.12,132.93,132.32,132.13,132.07,131.07,130.55,129.24,128.99,128.87,127.98,127.92,127.39,127.35,127.32,126.94,125.58,124.95,124.65,124.63,124.19,121.44,121.28,55.74,27.27,26.91,22.98,22.44.

[0100] HR-MS m / z:calcd for[M] + C 33 H 28 + :cald for425.2269;found:425.2267.

[0101] Experimental Example 1

[0102] Weigh 0.25mg, 0.125mg, 0.0625mg, 0.0312mg and 0.0156mg of DAE-1 into 10mL volumetric flasks respectively, and make up the volume with chromatographic methanol solution to obtain five sample solutions with different concentrations. The concentrations of the sample solutions are 5.09×10 -5 mol / L, 2.55×10 -5 mol / L, 1.27×10 -5 mol / L, 6.37×10 -6 mol / L, 3.18×10 -6 mol / L. Use an ultraviolet-visible spectrophotometer to measure the ultraviolet-visible absorption spectra of the above five DAE-1 samples with different concentrations. The results are as follows Figure 1As shown, DAE-1 is an open-ring isomer at this time, and the maximum absorption wavelength λ = 288 nm; by performing regression analysis on the maximum absorption wavelength, it can be obtained that the absorbance of compound DAE-1 at the same wavelength is positively correlated with its corresponding concentration, that is, it conforms to Lambert-Beer's law (Abs = εbc).

[0103] DAE-1 was irradiated in a chromatographic methanol solution under ultraviolet light at 254 nm, and the ultraviolet-visible absorption spectra at different irradiation times are as Figure 2 shown. From Figure 2 it can be seen that as the irradiation time increases, the absorption intensity at the maximum absorption wavelength of DAE-1 gradually weakens, while the absorption intensities at 361 nm, 377 nm and 556 nm gradually increase, and its isosbestic point is at 321 nm, thus confirming the existence of two isomers in the system, namely the open-ring isomer and the closed-ring isomer.

[0104] Weigh 0.2 mg, 0.16 mg, 0.12 mg, 0.08 mg and 0.04 mg of DAE-1 into 10 mL volumetric flasks respectively, and make up the volume with chromatographic acetonitrile solution to obtain five sample solutions with different concentrations. The concentrations of the sample solutions are 4.07×10 -5 mol / L, 3.26×10 -5 mol / L, 2.45×10 -5 mol / L, 1.63×10 -5 mol / L, 8.15×10 -6 mol / L. Use an ultraviolet-visible spectrophotometer to measure the ultraviolet-visible absorption spectra of the above five DAE-1 samples with different concentrations. The results are as Figure 3 shown. It can be obtained that DAE-1 is an open-ring isomer at this time, and the maximum absorption wavelength λ = 293 nm; by performing regression analysis on the maximum absorption wavelength, it can be obtained that the absorbance of compound DAE-1 at the same wavelength is positively correlated with its corresponding concentration, that is, it conforms to Lambert-Beer's law (Abs = εbc).

[0105] DAE-1 was irradiated in a chromatographic acetonitrile solution under ultraviolet light at 254 nm, and the ultraviolet-visible absorption spectra at different irradiation times are as Figure 4 shown. From Figure 4 it can be seen that as the irradiation time increases, the absorption intensity at the maximum absorption wavelength of DAE-1 gradually weakens, while the absorption intensities at 361 nm, 377 nm and 556 nm gradually increase, and its isosbestic point is at 321 nm, thus confirming the existence of two isomers in the system, namely the open-ring isomer and the closed-ring isomer.

[0106] Weigh 0.20 mg, 0.10 mg, 0.05 mg, 0.025 mg, and 0.013 mg of DAE-1 into 10-mL volumetric flasks respectively, and make up the volume with chromatographic n-hexane solution to obtain five sample solutions with different concentrations. The concentrations of the sample solutions are 1.10×10 - 4 mol / L, 5.09×10 -5 mol / L, 2.55×10 -5 mol / L, 1.27×10 -5 mol / L, 6.37×10 -6 mol / L. Use an ultraviolet-visible spectrophotometer to measure the ultraviolet-visible absorption spectra of the above five DAE-1 samples with different concentrations. The results are as shown in Figure 5 . It can be obtained that DAE-1 is an open-ring isomer at this time, and the maximum absorption wavelength λ = 288 nm at this time. By performing regression analysis on the maximum absorption wavelength, it can be concluded that the absorbance of compound DAE-1 at the same wavelength is positively correlated with its corresponding concentration, that is, it conforms to the Lambert-Beer law (Abs = εbc).

[0107] Irradiate DAE-1 in chromatographic n-hexane solution under ultraviolet light at 254 nm. The ultraviolet-visible absorption spectra at different irradiation times are as shown in Figure 6 . It can be seen from Figure 6 that as the irradiation time increases, the absorption intensity at the maximum absorption wavelength of DAE-1 gradually weakens, while the absorption intensities at 361 nm, 377 nm, and 556 nm gradually increase. Its isosbestic point is at 321 nm, which confirms the existence of two isomers in the system, namely the open-ring isomer and the closed-ring isomer.

[0108] From the above experiments, it can be known that before irradiation, the maximum absorption wavelength of the open-ring isomer of DAE-1 is approximately at 288 nm in different chromatographic pure solutions, and there is no significant absorption in the visible light region. At this time, the solution color is colorless. The reason for the significant change in the ultraviolet-visible absorption spectrum of DAE-1 may be that its open-ring isomer undergoes a photoisomerization reaction under the illumination condition of 254 nm, generating a closed-ring isomer. After visible light irradiation with >480 nm, the absorption spectrum of the compound changes back to the original state again, that is, the compound generates an open-ring isomer from the closed-ring isomer.

[0109] Similarly, under the illumination condition, DAE-2 and DAE-3 also undergo the same photoisomerization reaction as DAE-1 ( Figure 7 is the ultraviolet-visible absorption spectra of different concentrations of diarylethene compounds in chromatographic methanol in Example 2; Figure 8It is the UV-Vis absorption spectrogram of the diarylethene compound in chromatographic methanol under different irradiation times in Example 2; Figure 9 It is the UV-Vis absorption spectrogram of the diarylethene compound in chromatographic acetonitrile at different concentrations in Example 2; Figure 10 It is the UV-Vis absorption spectrogram of the diarylethene compound in chromatographic acetonitrile under different irradiation times in Example 2;

[0110] Figure 11 It is the UV-Vis absorption spectrogram of the diarylethene compound in chromatographic n-hexane at different concentrations in Example 2; Figure 12 It is the UV-Vis absorption spectrogram of the diarylethene compound in chromatographic n-hexane under different irradiation times in Example 2; Figure 13 It is the UV-Vis absorption spectrogram of the diarylethene compound in chromatographic methanol at different concentrations in Example 3; Figure 14 It is the UV-Vis absorption spectrogram of the diarylethene compound in chromatographic methanol under different irradiation times in Example 3; Figure 15 It is the UV-Vis absorption spectrogram of the diarylethene compound in chromatographic acetonitrile at different concentrations in Example 3;

[0111] Figure 16 It is the UV-Vis absorption spectrogram of the diarylethene compound in chromatographic acetonitrile under different irradiation times in Example 3; Figure 17 It is the UV-Vis absorption spectrogram of the diarylethene compound in chromatographic n-hexane at different concentrations in Example 3; Figure 18 It is the UV-Vis absorption spectrogram of the diarylethene compound in chromatographic n-hexane under different irradiation times in Example 3).

[0112] As can be seen from the above examples, the present invention provides a diarylethene photochromic compound with light responsiveness. The photochromic compound prepared by the method of the present invention has the following advantages: the synthesis route is short, the synthesis method is simple, the raw materials required are inexpensive, and the operability is strong; it has the photochromic properties, strong anti-fatigue property and stability of traditional diarylethene compounds; it has the light-responsive structural characteristics, which can broaden the application range of diarylethene photochromic compounds in photochemistry. The diarylethene compound provided by the present invention is different from the traditional diarylethene photochromic compounds. Under the condition of ultraviolet light irradiation, the maximum absorption wavelength of the closed-loop isomer of DAE-1 is about 550 nm, the maximum absorption wavelength of the closed-loop isomer of DAE-2 is about 510 nm, and the maximum absorption wavelength of the closed-loop isomer of DAE-3 is about 460 nm. The change in the maximum absorption wavelength of this closed-loop isomer mainly depends on the length of the π-conjugated system of the closed-loop isomer after it undergoes a photoisomerization reaction. This characteristic makes it of important research significance in the applications such as molecular switches, optical devices and anti-counterfeiting marks.

[0113] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the various embodiments, reference can be made to each other.

[0114] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A photochromic diarylethene compound, characterized in that: The structure of the diarylethene compound is as follows: , or .

2. The method for preparing a photochromic diarylethene compound according to claim 1, characterized in that: The preparation method comprises the following steps: 2,3-Dibromo-1,1-dimethyl-1 H -Indene and boric acid lipid compounds undergo coupling reaction to obtain diarylethene compounds; The boric acid lipid compound comprises one or more of 2-methyl-5-phenyl-thiophene borate, 5-methyl-2-phenyl-thiazole borate and 2-methylnaphthalene borate; The boric acid lipid compound is , and One or more of the .

3. The method for preparing a photochromic diarylethene compound according to claim 2, characterized in that: The 2,3-dibromo-1,1-dimethyl-1 H The molar ratio of indene to the boric acid lipid compound is 1-3:2-7.

4. The method for preparing a photochromic diarylethene compound according to claim 3, characterized in that: The coupling reaction temperature is 70-110°C, and the coupling reaction time is 12-48 h.

5. The method for preparing a photochromic diarylethene compound according to any one of claims 2 to 4, characterized in that: The coupling reaction is carried out under catalyst conditions; The catalyst includes tetrakis(triphenylphosphine)palladium, palladium acetate and bis(diphenylphosphino)ferrocenepalladium dichloride.

6. The method for preparing a photochromic diarylethene compound according to claim 5, characterized in that: The preparation method of the diarylethene compound is as follows: 2,3-Dibromo-1,1-dimethyl-1 H -Indene, boric acid lipid compound, catalyst, alkaline substance, water and organic solvent are mixed to carry out coupling reaction to obtain diarylethene compound.

7. The method for preparing a photochromic diarylethene compound according to claim 6, characterized in that: The 2,3-dibromo-1,1-dimethyl-1 H The molar volume ratio of -indene, boric acid ester compound, catalyst, alkaline substance, water and organic solvent is 1~3 mol:2~7 mol:0.1~1 mol:40~70 mol:20~40 L:20~40 L.

8. The method for preparing a photochromic diarylethene compound according to claim 7, characterized in that: The alkaline substance includes one or more of sodium carbonate, tripotassium nitrate and potassium phosphate; The organic solvent includes tetrahydrofuran and / or 1,4-dioxane.

9. Use of the diarylethene compound prepared by the preparation method according to any one of claims 2 to 8 in optical information recording, anti-counterfeiting components and photosensitive liquid crystal materials.

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