Preparation method and application of green synthetic light conversion material

Abstract

The invention relates to the field of light conversion materials, and discloses a preparation method and application of a green synthetic light conversion material. 4, 7-dimethylbenzotriazole is used as a raw material, the benzotriazole light conversion agent is prepared through nucleophilic addition, metal-free catalysis aryl methyl activation and Suzuki coupling, liquid bromine and hydrogen bromide or chlorine and hydrogen chloride used in an existing synthesis process are avoided, the production safety is effectively improved, the benzotriazole light conversion agent is used in a photovoltaic adhesive film, and the photovoltaic adhesive film has the advantages that the production efficiency is improved, and the production cost is reduced. The aging resistance of the product can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of light conversion materials, and in particular to a preparation method and application of a green synthetic light conversion material. Background Art

[0002] With the update and iteration of photovoltaic cell technology, the demand for matching photovoltaic films has continued to increase. At present, N-type TOPcon and heterojunction cells (HJT) have replaced PERC cells due to their ultra-high cell efficiency and mature production process, and have gradually become the mainstream new generation of photovoltaic cells. However, both HJT cells and TOPcon cells have been proven to be sensitive to ultraviolet light. Under long-term exposure to ultraviolet light outdoors, the composition structure of the cell will be damaged, resulting in a significant decrease in power generation efficiency. Therefore, a matching encapsulation film is needed to solve this problem. There are currently two solutions. One is to use ultraviolet cut-off encapsulation film to filter ultraviolet light, but it will lose ultraviolet light energy, resulting in a significant attenuation of the initial power of the component; the other is to use a light-converting encapsulation film to achieve a red shift of the wavelength of ultraviolet photons that are harmful to the battery, and convert ultraviolet light to visible light that can be used by the battery. While shielding harmful ultraviolet light, it improves the efficiency of solar cells and effectively guarantees the life of the component. It can be seen that the use of light-converting film encapsulation is the best solution.

[0003] The light conversion agent is the most critical performance material for light conversion packaging films. A class of derivatives with benzotriazole as the core structure are important materials that can meet the requirements of light conversion performance, including key performance indicators such as quantum conversion efficiency and ultraviolet band extinction coefficient. There are many patents published on the synthesis of this type of compound. For example, patents with publication numbers CN103339221A, CN117327023A, CN117247362A, CN117720474A, and CN117510421A all disclose methods for the synthesis of benzotriazole compounds. The methods disclosed in the above patents mainly have three steps: starting from benzotriazole as the raw material, after nucleophilic addition, benzene ring halogenation, and Suzuki coupling, the process is as follows:

[0004] In the above process, the second step of the halogenation synthesis process uses liquid bromine and hydrogen bromide or chlorine gas and hydrogen chloride. The raw materials are highly oxidizing, highly corrosive, and strongly acidic substances. There are safety hazards in the enlarged synthesis process, and the residual acidic impurities will affect the product performance, especially in the application of packaging films, which has a very serious impact on product aging. Summary of the invention

[0005] The invention aims to overcome the problem that strong oxidizing, highly corrosive and strongly acidic substances are used as raw materials in the synthesis process of benzotriazole light conversion agents in the prior art, and the use of such substances in packaging films may cause product aging. The invention provides a preparation method and application of a green synthetic light conversion material, wherein 4,7-dimethylbenzotriazole is used as a raw material, and the benzotriazole light conversion agent is prepared by nucleophilic addition, metal-free catalytic arylmethyl activation and Suzuki coupling, thereby avoiding the use of liquid bromine and hydrogen bromide or chlorine and hydrogen chloride in the prior synthesis process, and effectively improving the production safety and product aging resistance.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: A method for preparing a green synthetic light-conversion material comprises the following steps: (1) Compound 1 undergoes a nucleophilic addition reaction with a halide to obtain compound 2; The structural formula of compound 1 is as follows: ; The structural formula of compound 2 is as follows: ; (2) Compound 2 reacts with B2pin2 in the presence of tert-butyl nitrite, N-hydroxyphthalimide, LiBr, 4A molecular sieve and tert-butyl isonicotinate to obtain compound 3; The structural formula of compound 3 is as follows: ; (3) Compound 3 and halogenated aromatic hydrocarbon or arylboronic acid undergo Suzuki coupling reaction to obtain the green synthetic light conversion material having the following structural formula: ; Wherein, R0 is selected from one of H, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted heteroalkyl, substituted or unsubstituted amino, substituted or unsubstituted amide, substituted or unsubstituted alkoxy, substituted or unsubstituted carboxyl, substituted or unsubstituted ester, and substituted or unsubstituted carbonyl; R1 is selected from one of H, substituted or unsubstituted aryl, and substituted or unsubstituted heteroaryl.

[0007] The present invention uses 4,7-dimethylbenzotriazole as a raw material, and prepares a benzotriazole light conversion agent through nucleophilic addition, metal-free catalytic arylmethyl activation and Suzuki coupling reaction. The reaction route is as follows:

[0008] The present invention replaces the second step of the benzene ring halogenation reaction in the traditional preparation method of the benzotriazole type light conversion agent with a metal-free catalytic aryl methyl activation reaction, thereby avoiding the liquid bromine and hydrogen bromide or chlorine and hydrogen chloride used in the benzene ring halogenation reaction, which are highly oxidizing, highly corrosive and highly acidic substances, avoiding the potential safety hazards in the synthesis process, and reducing the residual acidic impurities. The light conversion adhesive film can effectively improve the aging resistance of the product.

[0009] Preferably, in step (1), the molar ratio of compound 1 to the halide is 1:1-1.5; the halide is one of iodide, bromide and chloride.

[0010] Preferably, the nucleophilic addition reaction of step (1) is carried out in an organic solvent under nitrogen protection and with potassium carbonate as a catalyst, and the reaction temperature is 90-100° C.; the mass molar ratio of potassium carbonate to compound 1 is 2-4 g:10 mmol.

[0011] Preferably, in step (2), the molar ratio of compound 2 to B2pin2 is 1:2-5; the molar ratio of tert-butyl nitrite, N-hydroxyphthalimide, LiBr to compound 2 is 15-25:15-25:1-3:5; the mass molar ratio of 4A molecular sieve to compound 2 is 2-4 g:5 mmol; and the molar ratio of tert-butyl isonicotinate to B2pin2 is 1-2:20.

[0012] Preferably, in step (2), compound 2, tert-butyl nitrite, N-hydroxyphthalimide, LiBr and 4A molecular sieve are first added to organic solvent A, and reacted under nitrogen protection at a reaction temperature of 75-85°C; then B2pin2, TBI and organic solvent B are added to react at a reaction temperature of 100-120°C.

[0013] Preferably, the organic solvent A is acetonitrile; the organic solvent B is trifluorotoluene.

[0014] Preferably, in step (3), the molar ratio of compound 3 to halogenated aromatic hydrocarbon or arylboronic acid is 1:2-3.

[0015] Preferably, the Suzuki coupling reaction of step (3) is carried out in an organic solvent under nitrogen protection, catalyzed by a zero-valent palladium complex and the action of potassium carbonate and / or potassium bicarbonate; the molar ratio of the zero-valent palladium complex, potassium carbonate and / or potassium bicarbonate to compound 3 is 0.04-0.06:1-3:1; and the reaction temperature is 85-95°C.

[0016] The present invention also provides an application of the green synthetic light-conversion material prepared by the above-mentioned preparation method in a light-conversion adhesive film, characterized in that, in parts by weight, the raw materials of the light-conversion adhesive film include: 90 to 100 parts of EVA resin, 0.5 to 0.6 parts of a cross-linking agent, 0.5 to 0.8 parts of an auxiliary cross-linking agent, 0.3 to 0.5 parts of a silane coupling agent, 0.05 to 0.2 parts of a light stabilizer, and 0.05 to 0.3 parts of the green synthetic light-conversion material.

[0017] Preferably, the melt index of the EVA resin is 20-30 g / 10 min, and the mass content of VA is 28-33%.

[0018] Therefore, the present invention has the following beneficial effects: the present invention uses 4,7-dimethylbenzotriazole as a raw material, and obtains a benzotriazole light conversion agent through nucleophilic addition, metal-free catalytic aromatic methyl activation, and Suzuki coupling, thereby avoiding liquid bromine and hydrogen bromide or chlorine and hydrogen chloride used in traditional synthesis, and effectively improving the production safety and product aging resistance. DETAILED DESCRIPTION

[0019] The present invention is further described below in conjunction with specific implementation methods.

[0020] In the present invention, unless otherwise specified, all equipment and raw materials can be purchased from the market or are commonly used in the industry. The methods in the following embodiments, unless otherwise specified, are conventional methods in the art.

[0021] Overall embodiment:

[0022] A method for preparing a green synthetic light-conversion material comprises the following steps: (1) Compound 1 undergoes a nucleophilic addition reaction with a halide to obtain compound 2; The structural formula of compound 1 is as follows: ; The structural formula of compound 2 is as follows: ; (2) Compound 2 reacts with B2pin2 in the presence of tert-butyl nitrite (tBuONO), N-hydroxyphthalimide (NHPI), LiBr, 4A molecular sieve and tert-butyl isonicotinate (TBI) to obtain compound 3; The structural formula of compound 3 is as follows: ; (3) Compound 3 and halogenated aromatic hydrocarbon or arylboronic acid undergo Suzuki coupling reaction to obtain the green synthetic light conversion material having the following structural formula: ; Wherein, R0 is selected from one of H, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted heteroalkyl, substituted or unsubstituted amino, substituted or unsubstituted amide, substituted or unsubstituted alkoxy, substituted or unsubstituted carboxyl, substituted or unsubstituted ester, and substituted or unsubstituted carbonyl; R1 is selected from one of H, substituted or unsubstituted aryl, and substituted or unsubstituted heteroaryl.

[0023] As a specific implementation manner, in step (1), the molar ratio of compound 1 to the halide is 1:1-1.5; the halide is one of iodide, bromide and chloride.

[0024] As a specific implementation method, the nucleophilic addition reaction of step (1) is carried out under nitrogen protection, potassium carbonate catalysis and organic solvent, and the reaction temperature is 90-100° C.; the mass molar ratio of potassium carbonate to compound 1 is 2-4 g:10 mmol.

[0025] As a specific implementation manner, in step (2), the molar ratio of compound 2 to B2pin2 is 1:2~5; the molar ratio of tert-butyl nitrite, N-hydroxyphthalimide, LiBr to compound 2 is 15~25:15~25:1~3:5; the mass molar ratio of 4A molecular sieve to compound 2 is 2~4g:5mmol; the molar ratio of tert-butyl isonicotinate to B2pin2 is 1~2:20.

[0026] As a specific implementation method, in step (2), compound 2, tert-butyl nitrite, N-hydroxyphthalimide, LiBr and 4A molecular sieve are first added to organic solvent A, and reacted under nitrogen protection at a reaction temperature of 75-85°C; then B2pin2, TBI and organic solvent B are added to react at a reaction temperature of 100-120°C.

[0027] As a specific implementation manner, the organic solvent A is acetonitrile; the organic solvent B is trifluorotoluene.

[0028] As a specific implementation manner, in step (3), the molar ratio of compound 3 to halogenated aromatic hydrocarbon or arylboronic acid is 1:2-3.

[0029] As a specific embodiment, the Suzuki coupling reaction of step (3) is carried out in an organic solvent under nitrogen protection, catalysis by a zero-valent palladium complex and the action of potassium carbonate and / or potassium bicarbonate; the molar ratio of the zero-valent palladium complex, potassium carbonate and / or potassium bicarbonate to compound 3 is 0.04-0.06:1-3:1; and the reaction temperature is 85-95°C.

[0030] The green synthetic light-converting material prepared by the above preparation method is used in a light-converting adhesive film. The raw materials of the light-converting adhesive film include, by weight: 90 to 100 parts of EVA resin, 0.5 to 0.6 parts of a cross-linking agent, 0.5 to 0.8 parts of a co-cross-linking agent, 0.3 to 0.5 parts of a silane coupling agent, 0.05 to 0.2 parts of a light stabilizer, and 0.05 to 0.3 parts of the green synthetic light-converting material.

[0031] As a specific implementation manner, the melt index of the EVA resin is 20-30 g / 10 min, and the mass content of VA is 28-33%.

[0032] As a specific embodiment, the cross-linking agent is one or more of di-tert-butyl peroxide, 2,5-dimethyl-2,5-(bis-tert-butylperoxy)hexane, tert-butylperoxycarbonic acid-2-ethylhexyl ester (TBEC), 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 2-methyl-2-butyl-3,5,5-trimethylhexane peroxyester, 1,1-bis(tert-butylperoxy)cyclohexane, and tert-amyl peroxy 2-ethylhexyl carbonate.

[0033] As a specific implementation, the auxiliary cross-linking agent is one or more of triallyl isocyanurate, trimethylolpropane trimethacrylate, glycerol trihydroxypropyl ether triacrylate, trimethylpropane diallyl ether, triallyl cyanurate, trivinylmethoxysilane, trivinylethoxysilane, and triallylethoxysilane.

[0034] As a specific implementation, the silane coupling agent is one or more of vinyl triethoxysilane, vinyl trimethoxysilane, vinyl triacetoxysilane, vinyl tri(β-methoxyethoxy) silane, and γ-methacryloxypropyl trimethoxysilane.

[0035] As a specific embodiment, the light stabilizer is one or more of bis-2,2,6,6-tetramethylpiperidinol sebacate, bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, 4-(methyl)acryloyloxy-2,2,6,6-tetramethylpiperidine, 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinol, 3,5-di-tert-butyl-4-hydroxy-benzoic acid hexadecyl ester, and tris(1,2,2,6,6-pentamethyl-4-piperidinyl)phosphite.

[0036] As a specific implementation, the preparation method of the light-converting adhesive film is: EVA resin, a cross-linking agent, a co-cross-linking agent, a silane coupling agent, a light stabilizer and a green synthetic light-converting material are mixed, and a film is cast by a casting machine to obtain the light-converting adhesive film.

[0037] Embodiment 1:

[0038] A method for preparing a green synthetic light-conversion material, the reaction route is:

[0039] The steps include: (1) Preparation of 2-isobutyl-4,7-dimethyl-2H-benzo[d][1,2,3]triazole (Compound 2): Under nitrogen protection, 4,7-dimethylbenzotriazole (Compound 1) (1.47 g, 10 mmol), potassium carbonate (3 g) and 50 mL DMF were added to a flask and stirred evenly. Isobutyl iodide (2.02 g, 11 mmol) was dissolved in 10 mL DMF and added to the system, and stirred to dissolve. The obtained mixture was stirred at 95°C under nitrogen. The reaction was monitored by thin layer chromatography. After the reaction was completed, the system was cooled to room temperature, extracted with ethyl acetate, washed with saturated brine, and the organic layer was collected and dried over anhydrous sodium sulfate and concentrated to dryness. The crude product was separated by petroleum ether / ethyl acetate column chromatography to obtain 1.85 g of a solid product of Compound 2 (yield 91%). 1 H NMR (500 MHz, Chloroform-d) δ 7.36 (s, 2H), 4.18 (d, J = 3.7 Hz,2H), 2.51 (s, 6H), 2.24 (dtp, J = 10.3, 6.8, 3.4 Hz, 1H), 1.06 (d, J = 6.9Hz, 6H).

[0040] (2) Preparation of 2-isobutyl-4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2H-benzo[d][1,2,3]triazole (Compound 3): Under nitrogen protection, compound 2 (1.0 g, 5 mmol), tBuONO (2.1 g, 20 mmol), NHPI (3.3 g, 20 mmol), additive LiBr (173.7 mg, 2 mmol), 4A molecular sieve 3 g, acetonitrile 20 mL were added to the flask and reacted at 80 ° C; then B2pin2 (5.1 g, 20 mmol), TBI (0.27 g, 1.5 mmol), PhCF3 (20 mL) were added, and the reaction was carried out at 110 ° C, and the reaction was monitored by thin layer chromatography. After the reaction was completed, it was extracted with ethyl acetate, the organic layer was collected, and then dried over anhydrous sodium sulfate, and concentrated to dryness. The crude product was separated by petroleum ether / ethyl acetate column chromatography to obtain 1.8 g of compound 3 solid product (yield 75%); 1H NMR (500 MHz, Chloroform-d) δ 7.51 (s, 2H), 4.05 (d, J = 3.5 Hz, 2H), 2.29 (dtp, J = 10.3, 7.0, 3.5 Hz, 1H), 1.23 (s, 24H), 1.13 (d, J = 6.9Hz, 6H).

[0041] (3) Preparation of 4,7-bis(4-(tert-butyl)phenyl)-2-isobutyl-2H-benzo[d][1,2,3]triazole (Structural Formula 1): Pd(Ph3P)4 (57.8 mg, 0.05 mmol), K2CO3 (276.4 mg, 2 mmol), and compound 3 (423.2 mg, 1 mmol) were directly weighed into a 25 mL reaction bottle; under nitrogen protection, DMF (6 mL) and 4-(tert-butyl)iodobenzene (520 mg, 2 mmol) were added in sequence; the reaction mixture was heated and stirred at 90 °C (TLC monitoring); the mixture was cooled to a constant temperature and diluted with water (10 mL). The layers were separated and extracted with ethyl acetate, washed with saturated brine, the organic layer was collected, dried over anhydrous sodium sulfate, and concentrated to dryness; the crude product was separated by petroleum ether / ethyl acetate column chromatography to obtain 356.0 mg (yield 81%) of solid product of structural formula 1, which was a white solid, namely the green synthetic light conversion material; 1 H NMR (500 MHz, Chloroform-d) δ 7.93 (s, 2H), 7.87 – 7.81 (d, 4H), 7.53 – 7.47 (d, 4H), 4.19 (d, J = 3.7 Hz, 2H), 2.22 (dtq, J = 10.5, 6.9, 3.5 Hz, 1H), 1.34 (s, 18H), 1.15 (d, J = 6.9 Hz, 6H).

[0042] Embodiment 2:

[0043] A method for preparing a green synthetic light-conversion material, the reaction route is:

[0044] The steps include: (1) Preparation of 4,7-dimethyl-2-propyl-2H-benzo[d][1,2,3]triazole (Compound 2): Under nitrogen protection, 4,7-dimethylbenzotriazole (Compound 1) (1.47 g, 10 mmol), potassium carbonate (3 g) and 50 mL DMF were added to a flask and stirred evenly. Then, iodinated n-propane (1.87 g, 11 mmol) was dissolved in 10 mL DMF and added to the system, and stirred to dissolve. The obtained mixture was stirred at 95°C under nitrogen. The reaction was monitored by thin layer chromatography. After the reaction was completed, the system was cooled to room temperature, extracted with ethyl acetate, washed with saturated brine, the organic layer was collected, dried over anhydrous sodium sulfate, and concentrated to dryness. The crude product was separated by petroleum ether / ethyl acetate column chromatography to obtain 1.63 g of a solid product of Compound 2 (yield 86%). 1 H NMR (500 MHz, Chloroform-d) δ 7.35 (s, 2H), 4.60 (dt, J = 13.4, 6.3Hz, 2H), 2.49 (s, 6H), 1.87 (qt, J = 7.6, 6.2 Hz, 2H), 1.08 (t, J = 7.6 Hz,3H).

[0045] (2) Preparation of 2-propyl-4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2H-benzo[d][1,2,3]triazole (Compound 3): Under nitrogen protection, compound 2 (0.95 g, 5 mmol), tBuONO (2.1 g, 20 mmol), NHPI (3.3 g, 20 mmol), additive LiBr (173.7 mg, 2 mmol), 4A molecular sieve 3 g, acetonitrile 20 mL were added to the flask and reacted at 80 ° C; then B2pin2 (5.1 g, 20 mmol), TBI (0.27 g, 1.5 mmol), PhCF3 (20 mL) were added, and the reaction was carried out at 110 ° C, and the reaction was monitored by thin layer chromatography. After the reaction was completed, it was extracted with ethyl acetate, the organic layer was collected, and then dried over anhydrous sodium sulfate, concentrated and dried; the crude product was separated by petroleum ether / ethyl acetate column chromatography to obtain 1.34 g of compound 3 solid product (yield 65%); 1 H NMR (500 MHz, Chloroform-d) δ 7.52 (s, 2H), 4.27 (t, J = 6.3 Hz, 2H), 1.87 (dtd, J = 13.9, 7.7, 6.3 Hz, 2H), 1.23 (s, 24H), 1.18 (t, J = 7.6Hz, 3H).

[0046] (3) Preparation of 4,7-bis(4-(tert-butyl)phenyl)-2-propyl-2H-benzo[d][1,2,3]triazole (Structure 2): Pd(Ph3P)4 (57.8 mg, 0.05 mmol), KHCO3 (200.4 mg, 2 mmol), and compound 3 (423.2 mg, 1 mmol) were directly weighed into a 25 mL reaction bottle. Under nitrogen protection, DMF (6 mL) and 4-tert-butyl 2-iodo-1,3-dimethylbenzene (520 mg, 2 mmol) were added in sequence; the reaction mixture was heated and stirred at 90 °C (TLC monitoring); the mixture was cooled to a constant temperature and diluted with water (10 mL); the layers were separated and extracted with ethyl acetate, washed with saturated brine, the organic layer was collected, dried over anhydrous sodium sulfate, and concentrated to dryness; the crude product was separated by petroleum ether / ethyl acetate column chromatography to obtain 319.2 mg (yield 75%) of a solid product of structure 2, which was a white solid, namely the green synthetic light conversion material; 1 HNMR (500 MHz, Chloroform-d) δ 7.73 (s, 2H), 7.26 (s, 4H), 4.57 (t, J = 6.2Hz, 2H), 2.72 (s, 12H), 1.87 (qt, J = 7.6, 6.2 Hz, 2H), 1.32 (s, 18H), 1.15(t, J = 7.6 Hz, 3H).

[0047] Embodiment 3:

[0048] A method for preparing a green synthetic light-conversion material, the reaction route is:

[0049] The steps include: (1) Preparation of 4,7-dimethyl-2-octyl-2H-benzo[d][1,2,3]triazole (Compound 2): Under nitrogen protection, 4,7-dimethylbenzotriazole (Compound 1) (1.47 g, 10 mmol), potassium carbonate (3 g) and 50 mL DMF were added to the flask and stirred evenly. 1-iodooctane (2.64 g, 11 mmol) was dissolved in 10 mL DMF and added to the system, and stirred to dissolve. The obtained mixture was stirred at 95 °C under nitrogen. The reaction was monitored by thin layer chromatography. After the reaction was completed, the system was cooled to room temperature, extracted with ethyl acetate, washed with saturated brine, the organic layer was collected, dried over anhydrous sodium sulfate, and concentrated to dryness. The crude product was separated by petroleum ether / ethyl acetate column chromatography to obtain 2.26 g of compound 2 solid product (yield 87%).1 H NMR (500 MHz, Chloroform-d) δ 7.36 (s, 2H), 4.63 (t, J = 6.2 Hz, 2H), 2.51 (s, 6H), 1.87 (p, J = 6.5 Hz, 2H), 1.44 – 1.36 (m, 2H), 1.39 – 1.24 (m,8H), 0.94 – 0.83 (m, 3H).

[0050] (2) Preparation of 2-octyl-4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2H-benzo[d][1,2,3]triazole (Compound 3): Under nitrogen protection, compound 2 (1.3 g, 5 mmol), tBuONO (2.1 g, 20 mmol), NHPI (3.3 g, 20 mmol), additive LiBr (173.7 mg, 2 mmol), 4A molecular sieve 3 g, acetonitrile 20 mL were added to the flask, and the reaction was carried out at 80 ° C; then B2pin2 (5.1 g, 20 mmol), TBI (0.27 g, 1.5 mmol), PhCF3 (20 mL) were added, and the reaction was carried out at 110 ° C, and the reaction was monitored by thin layer chromatography; after the reaction was completed, it was extracted with ethyl acetate, the organic layer was collected, and then dried over anhydrous sodium sulfate, and concentrated to dryness; the crude product was separated by petroleum ether / ethyl acetate column chromatography to obtain 1.45 g of compound 3 solid product (yield 60%); 1 H NMR (500 MHz, Chloroform-d) δ 7.51 (s, 2H), 4.29 (t, J = 6.3 Hz, 2H), 1.86 (p, J = 6.5 Hz, 2H), 1.55 (p, J = 6.7 Hz, 2H), 1.37 – 1.22 (m, 8H), 1.22 (s, 24H), 0.93 – 0.86 (m, 3H).

[0051] (3) Preparation of 4,7-bis(4-(tert-butyl)phenyl)-2-octyl-2H-benzo[d][1,2,3]triazole (Structural Formula 3): Pd(Ph3P)4 (57.8 mg, 0.05 mmol), K2CO3 (276.4 mg, 2 mmol), and compound 3 (483.3 mg, 1 mmol) were directly weighed into a 25 mL reaction bottle; under nitrogen protection, DMF (6 mL) and 4-(tert-butyl)iodobenzene (520 mg, 2 mmol) were added in sequence; the reaction mixture was heated and stirred at 90 °C (TLC monitoring); the mixture was cooled to a constant temperature and diluted with water (10 mL); the layers were separated and extracted with ethyl acetate, washed with saturated brine, the organic layer was collected, dried over anhydrous sodium sulfate, and concentrated to dryness; the crude product was separated by petroleum ether / ethyl acetate column chromatography to obtain 304.9 mg (yield 61.5%) of a solid product of structural formula 3, which was a white solid, namely the green synthetic light conversion material; 1 H NMR (500 MHz, Chloroform-d) δ 7.93 (s, 2H), 7.87 – 7.81 (d, 4H), 7.53 – 7.46 (d, 4H), 4.66 (t, J = 6.3 Hz, 2H), 1.87 (p, J = 6.5 Hz, 2H), 1.46 – 1.37 (m, 2H), 1.35 –1.23 (m, 8H), 1.352 (s, 18H), 0.93 – 0.85 (m, 3H).

[0052] Comparative Example 1: A method for preparing a light-converting material, the reaction route is:

[0053] The steps include: (1) Preparation of ethyl 4-(2H-benzo[D][1,2,3]triazol-2-yl)butanoate (Compound 5): Under nitrogen protection, benzotriazole (compound 4) (1.19 g, 10 mmol), potassium carbonate (3 g) and butanone were added to a flask and mixed and stirred evenly. Ethyl 4-bromobutyrate (2.14 g, 11 mmol) was added dropwise to the mixture at 80°C. The reaction was continued for 2 hours after the addition. After the reaction was completed, the mixture was filtered and washed with ethyl acetate to obtain a filtrate. The filtrate was then distilled under reduced pressure to obtain a liquid mixture. The mixture was distilled under reduced pressure (10 mmHg) at 120°C to obtain 0.98 g of a light yellow liquid of compound 5 (yield 42.0%). 1H NMR (500 MHz, Chloroform-d) δ 7.96-7.89 (m, 2H),7.42 – 7.35 (m, 2H), 4.63 (t, J = 6.3 Hz, 2H), 4.12 (q, J = 7.0 Hz, 2H), 2.57(t, J = 7.1 Hz, 2H), 2.27 – 2.18 (m, 2H), 1.23 (t, J = 6.9 Hz, 3H).

[0054] (2) Preparation of ethyl 4-(4,7-dibromo-2H-benzo[d][1,2,3]triazol-2-yl)butanoate (Compound 6) A mixed solution of compound 5 (1.17 g, 5 mmol) and aqueous hydrogen bromide solution was heated to 110°C (condensation reflux), and then liquid bromine was slowly added dropwise to the above liquid. After the addition was complete, the reaction was continued for 2 hours, and then cold water and toluene were added for extraction. The organic layer was taken and then washed with saturated aqueous sodium bicarbonate and sodium chloride solutions respectively, and then dried with anhydrous sodium sulfate, filtered, and concentrated under reduced pressure; the concentrate was recrystallized with isopropanol to obtain 0.98 g of a solid product of compound 6 (yield 50.1%); 1 H NMR (500 MHz, Chloroform-d) δ 7.66 (s, 2H), 4.71 (t, J = 6.2 Hz, 2H), 4.12(q, J = 7.0 Hz, 2H), 2.58 (t, J = 7.1 Hz, 2H), 2.30 – 2.21 (m, 2H), 1.21 (t,J = 7.0 Hz, 3H).

[0055] (3) Preparation of ethyl 4-(4,7-bis(4-(tert-butyl)phenyl)-2H-benzo[D][1,2,3]triazol-2-yl)butanoate (Structural Formula 4): Compound 6 (391 mg, 1 mmol), 4-tert-butylphenylboronic acid (356 mg, 2 mmol), PbCl2(PPh3)2 (401.4 mg, 0.5 mmol) and potassium carbonate (276.4 mg, 2 mmol) were added to a reaction bottle, DMF was injected under a nitrogen environment, and then oxygen-free deionized water was added to the reaction container. The reaction was carried out at 90° C. for 2 hours, and then deionized water was added to obtain a precipitate. The precipitate was dissolved with ethyl acetate, and then n-hexane was added to precipitate a black precipitate. After removing the black precipitate, the organic solution was concentrated by vacuum distillation, and the concentrate was recrystallized with isopropanol to obtain 263.77 mg (yield 53%) of a solid product of structural formula 4, which was a white solid, namely the light conversion material;1 H NMR (500 MHz, Chloroform-d) δ 7.93 (s, 2H), 7.87 – 7.81 (m, 4H), 7.52 – 7.46 (m, 4H), 4.72 (t, J = 6.3Hz, 2H), 4.12 (q, J = 6.9 Hz, 2H), 2.57 (t, J = 7.1 Hz, 2H), 2.29 – 2.20 (m,2H), 1.33 (s, 18H), 1.21 (t, J = 6.9 Hz, 3H).

[0056] Application Example 1~Application Example 3 and Comparative Application Example 1: The light-converting materials prepared in Examples 1 to 3 and Comparative Example 1 were respectively made into light-converting adhesive films, and the light-converting adhesive films of Application Examples 1 to 3 and Comparative Example 1 were obtained. The preparation method of the light-converting adhesive film is as follows: by weight, 98.25 parts of EVA resin (melt index of 25 g / 10 min, VA content of 30%), 0.55 parts of cross-linking agent 2,5-dimethyl-2,5-(bis-tert-butylperoxy)hexane, 0.6 parts of auxiliary cross-linking agent triallyl isocyanurate, 0.4 parts of vinyl triethoxysilane, 0.1 parts of light stabilizer sebacic acid bis-2,2,6,6-tetramethylpiperidinol, 0.1 parts of the light-converting materials prepared in Examples 1 to 3 and Comparative Example 1 were mixed, and cast into a film having a gram weight of 420 g / m 2 Light-transmitting film.

[0057] The UV240kWh aging test was carried out on the light-converting film prepared above. The results are shown in Table 1. Table 1

[0058] It can be seen from the data in Table 1 that after the UV240kWh aging test, the film with the light conversion material prepared by the method of the present invention in Examples 1 to 3 has better anti-aging performance than Comparative Example 1. On the one hand, the stability of the light transmittance in the ultraviolet region is higher, and the light conversion effect is better maintained; on the other hand, the yellowing value of the light conversion material film is lower, which reflects its better stability and lower impact on the yellowing of the film aging; the attenuation of small components is also lower, and the impact on component aging is weaker. Therefore, the synthesis route of the present invention can produce a light conversion material with better anti-aging effect.

[0059] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions, which should be included in the scope of the claims of the present invention.

Claims

1. A method for preparing a green synthetic light-conversion material, comprising: Follow these steps: (1) Compound 1 undergoes a nucleophilic addition reaction with a halide to obtain compound 2; The structural formula of compound 1 is as follows: ； The structural formula of compound 2 is as follows: ； (2) Compound 2 reacts with B2pin2 in the presence of tert-butyl nitrite, N-hydroxyphthalimide, LiBr, 4A molecular sieve and tert-butyl isonicotinate to obtain compound 3; The structural formula of compound 3 is as follows: ； (3) Compound 3 and halogenated aromatic hydrocarbon or arylboronic acid undergo Suzuki coupling reaction to obtain the green synthetic light conversion material having the following structural formula: ； Wherein, R0 is selected from one of H, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted heteroalkyl, substituted or unsubstituted amino, substituted or unsubstituted amide, substituted or unsubstituted alkoxy, substituted or unsubstituted carboxyl, substituted or unsubstituted ester, and substituted or unsubstituted carbonyl; R1 is selected from one of H, substituted or unsubstituted aryl, and substituted or unsubstituted heteroaryl.

2. The method for preparing the green synthetic light-conversion material according to claim 1, characterized in that: In step (1), the molar ratio of compound 1 to the halide is 1:1-1.5; the halide is one of iodide, bromide and chloride.

3. The method for preparing the green synthetic light-conversion material according to claim 1 or 2, characterized in that: The nucleophilic addition reaction of step (1) is carried out in an organic solvent under nitrogen protection and potassium carbonate catalysis, and the reaction temperature is 90-100° C. The mass molar ratio of potassium carbonate to compound 1 is 2-4 g:10 mmol.

4. The method for preparing the green synthetic light conversion material according to claim 1, characterized in that: In step (2), the molar ratio of compound 2 to B2pin2 is 1:2~5; the molar ratio of tert-butyl nitrite, N-hydroxyphthalimide, LiBr to compound 2 is 15~25:15~25:1~3:5; the mass molar ratio of 4A molecular sieve to compound 2 is 2~4g:5mmol; the molar ratio of tert-butyl isonicotinate to B2pin2 is 1~2:

20.

5. The method for preparing the green synthetic light conversion material according to claim 1 or 4, characterized in that: In step (2), compound 2, tert-butyl nitrite, N-hydroxyphthalimide, LiBr and 4A molecular sieve are first added to organic solvent A and reacted under nitrogen protection at a reaction temperature of 75-85°C; then B2pin2, TBI and organic solvent B are added to react at a reaction temperature of 100-120°C.

6. The method for preparing the green synthetic light-conversion material according to claim 5, characterized in that: The organic solvent A is acetonitrile; the organic solvent B is trifluorotoluene.

7. The method for preparing the green synthetic light-conversion material according to claim 1, characterized in that: In step (3), the molar ratio of compound 3 to halogenated aromatic hydrocarbon or arylboronic acid is 1:2-3.

8. The method for preparing the green synthetic light-conversion material according to claim 1 or 7, characterized in that: The Suzuki coupling reaction of step (3) is carried out in an organic solvent under nitrogen protection, catalyzed by a zero-valent palladium complex and the action of potassium carbonate and / or potassium bicarbonate; the molar ratio of the zero-valent palladium complex, potassium carbonate and / or potassium bicarbonate to compound 3 is 0.04-0.06:1-3:1; and the reaction temperature is 85-95°C.

9. An application of a green synthetic light-converting material prepared by the preparation method according to any one of claims 1 to 8 in a light-converting adhesive film, characterized in that: The raw materials of the light-converting adhesive film include, by weight: 90-100 parts of EVA resin, 0.5-0.6 parts of cross-linking agent, 0.5-0.8 parts of auxiliary cross-linking agent, 0.3-0.5 parts of silane coupling agent, 0.05-0.2 parts of light stabilizer, and 0.05-0.3 parts of the green synthetic light-converting material.

10. The use of the green synthetic light-converting material in a light-converting adhesive film according to claim 9, characterized in that: The melt index of the EVA resin is 20-30 g / 10 min, and the mass content of VA is 28-33%.

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