A fluorescent compound containing triazole and benzofuran fused with a benzene ring, a light-converting film and its application

Abstract

The present invention relates to the field of optoelectronic semiconductor technology, and specifically discloses a fluorescent compound containing triazole and benzofuran fused with a benzene ring, a light conversion film and its application. The fluorescent compound has excellent light conversion performance, can convert ultraviolet light into a yellow light region with higher battery utilization efficiency, has a high molar absorption coefficient ε in the ultraviolet region, and has the ability to absorb light covering the entire ultraviolet region. At the same time, the emission wavelength is within the wavelength range that the battery can use more efficiently, the molecule has strong photothermal stability, and has excellent resistance to ultraviolet aging; and the fluorescent quantum efficiency of the fluorescent compound is high. Compared with the prior art, under the premise of obtaining the same gain, its usage can be greatly reduced when making a light conversion film. In addition, the fluorescent compound is an organic small molecule with low synthesis cost, easy-to-adjust structure, mild synthesis conditions, suitable for commercial large-scale production, and high market value.

Description

Technical Field

[0001] The invention relates to the technical field of optoelectronic semiconductors, and specifically discloses a fluorescent compound containing triazole and benzofuran fused with a benzene ring, a light conversion film and applications thereof. Background Art

[0002] Photovoltaic power generation is a technology that uses solar radiation energy to generate electricity. It converts sunlight into direct current through the photovoltaic effect. N-type battery modules are currently the most mainstream photovoltaic technology, mainly including TOPCon and heterojunction (HJT). The average photoelectric conversion efficiency of heterojunction cells is about 1% higher than that of TOPCon. This is largely due to the excellent surface passivation ability of intrinsic amorphous silicon for crystalline silicon. The only drawback is that the transparent conductive oxide coating (TCO) film layer and the amorphous silicon film layer absorb ultraviolet rays, making the current of its battery lower than that of ordinary batteries. Heterojunction cells are multi-layer structures, one of which uses amorphous or microcrystalline silicon. Under ultraviolet exposure, due to the presence of Si-H groups on the surface, the efficiency of the module decays faster than other types of batteries. Existing solutions include ultraviolet cut-off film or light-conversion film. If a cut-off film is used to filter ultraviolet rays, ultraviolet energy will be lost (the energy in the ultraviolet band accounts for 9% of the total energy of solar radiation), and the initial power attenuation of the module will be large. Using a light-conversion film to absorb ultraviolet rays and convert them into visible light can improve the efficiency of the cell without modifying the cell passivation technology.

[0003] The core of the light-converting film to improve the efficiency of the battery is the light conversion agent dispersed in it. The existing light conversion agents mainly include rare earth organic light conversion agents, organic fluorescent compounds, rare earth inorganic light conversion agents, rare earth nano light conversion agents and semiconductor quantum dots. Among them, the cost of materials containing rare earth elements is relatively high. The rare earth organic ligand complex as a light conversion agent of the film has problems such as uneven dispersion, narrow absorption band, low conversion efficiency, and easy discoloration of organic ligands after long-term use; semiconductor quantum dots (such as CdS, CdTe, ZnS, etc.) as photovoltaic film converters have environmental risks and "potential induced decay phenomenon" caused by the precipitation of metal particles. At the same time, the large-scale industrialization of quantum dots with stable quality is still imperfect. Organic fluorescent compounds have many advantages such as easy structural design, low synthesis cost, and adjustable performance, but the performance of the compounds used in the current public technology is insufficient. The wavelength range of the spectral response of general solar cells is between 320~1100nm, among which the efficiency for green and red light is the highest. Benzotriazole molecules, fluorescent pigment compounds currently used in commercial light-conversion films, have excellent ultraviolet light absorption properties, but the wavelength of visible light released after absorbing photons and converting them is basically in the blue light region, resulting in low battery utilization efficiency and low gain. Light-conversion materials with suitable emission wavelengths have defects such as insufficient absorption spectrum coverage, low molar absorption coefficient, poor photothermal stability, difficult processing within the melting point range, low quantum yield or high price that cannot be commercialized. Summary of the invention

[0004] In view of the above problems, the present invention provides a fluorescent compound containing triazole and benzofuran fused with a benzene ring, a light conversion film and its application. The fluorescent compound is used as a core material to manufacture solar cells, which can effectively improve the operating life and photoelectric conversion efficiency.

[0005] In order to solve the above technical problems, the technical solution provided by the present invention is:

[0006] In a first aspect, the present invention provides a fluorescent compound containing triazole and benzofuran fused with a benzene ring, and its structural formula is shown in Formula 1:

[0007]

[0008] Formula 1;

[0009] In the formula, X is hydrogen or fluorine;

[0010] R 1 Taken from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group;

[0011] R 2 Derived from: hydrogen, fluorine, trifluoromethyl, cyano, C1~C6 alkoxy, aryl, heteroaryl, substituted aryl, substituted heteroaryl, arylvinyl, heteroarylvinyl, arylethynyl, heteroarylethynyl or N,N-disubstituted arylamine;

[0012] R 3 Derived from: hydrogen, fluorine, trifluoromethyl, cyano, C1~C6 alkoxy, aryl, heteroaryl, substituted aryl, substituted heteroaryl, arylvinyl, heteroarylvinyl, arylethynyl, heteroarylethynyl or N,N-disubstituted arylamine;

[0013] R 2 , R 3 At least one of them is hydrogen or fluorine.

[0014] It should be noted that “R 2 , R 3 At least one of them is hydrogen or fluorine" can be understood as "R 2 , R 3 At least one of them is X", that is, the structural formula of the fluorescent compound containing triazole and benzofuran fused with a benzene ring is Formula 2 or Formula 3:

[0015]

[0016] "Aryl" refers to a carbon aromatic group containing one or more rings.

[0017] "Heteroaryl" refers to an aromatic group containing one or more heteroatoms, which may contain one ring or multiple fused rings. When there are two or more heteroatoms, they may be the same or different. In a fused ring, the heteroatoms may be in one ring or shared by the rings.

[0018] The term "substituted aryl group" refers to an aryl group having a substituent attached to at least one position other than the position at which the benzofuran-fused benzotriazole structure (ie, the parent structure) is attached.

[0019] The term "substituted heteroaryl" refers to a heteroaryl group having a substituent attached to at least one position other than the position where the heteroaryl group is attached to the benzofuran-fused benzotriazole structure.

[0020] "Arylvinyl" refers to an ethylene structure having one carbon atom bonded to an aryl group and another carbon atom bonded to a benzofuran-fused benzotriazole structure.

[0021] "Heteroarylvinyl" refers to an ethylene structure having one carbon atom bonded to a heteroaryl group and another carbon atom bonded to a benzofuran-fused benzotriazole structure.

[0022] "Arylethynyl" refers to an acetylene structure having one carbon atom bonded to an aryl group and another carbon atom bonded to a benzofuran-fused benzotriazole structure.

[0023] "Heteroaryl ethynyl" refers to an ethynyl structure having one carbon atom bonded to a heteroaryl group and another carbon atom bonded to a benzofuran-fused benzotriazole structure.

[0024] "N,N-disubstituted arylamine" refers to a substituent formed by three chemical bonds of the nitrogen atom, two of which are connected to the "substituted aryl" and the other is connected to the benzotriazole structure fused to benzofuran. The N,N-disubstituted arylamine may be symmetrical or asymmetrical.

[0025] Compared with the prior art, the fluorescent compound containing triazole and benzofuran fused with a benzene ring (hereinafter referred to as the fluorescent compound) provided by the present invention has excellent light conversion performance, can convert ultraviolet light into the yellow light region with higher battery utilization efficiency, has a high molar absorption coefficient ε in the ultraviolet region, has the ability to absorb light covering the entire ultraviolet region, and at the same time, the emission wavelength is within the wavelength range that the battery can use more efficiently, has strong molecular photothermal stability, and has excellent resistance to ultraviolet aging; and the fluorescent quantum efficiency of the fluorescent compound is high. Compared with the prior art, under the premise of obtaining the same gain, the amount of use can be greatly reduced when making a light conversion film. In addition, the fluorescent compound is an organic small molecule with low synthesis cost, easy structure adjustment, mild synthesis conditions, suitable for commercial large-scale production, and high market value.

[0026] The results of the examples show that the maximum absorption wavelength of the fluorescent compound provided by the present invention is 383-432 nm, the maximum emission wavelength is 569-628 nm, the molar absorption coefficient (ε) at the maximum absorption wavelength is 29200-31400 L / (mol·cm), and the light conversion efficiency is above 93%, and can even exceed 96%. When the fluorescent compound is used in the photovoltaic module of a solar cell, the comprehensive performance of the solar cell module can be significantly improved in many aspects.

[0027] Preferably, R 1 Taken from: C1~C18 straight chain alkyl, C3~C18 branched chain alkyl, C3~C18 cycloalkyl, C1~C5 straight chain silyl with trimethylsilyl as terminal group or C3~C5 branched chain silyl with trimethylsilyl as terminal group.

[0028] Preferably, the C1~C6 alkoxy group is a C1~C6 straight chain alkoxy group, a C3~C6 branched chain alkoxy group or a C2~C6 cycloalkoxy group. Further preferably, the C1~C6 alkoxy group is a C1~C6 straight chain alkoxy group.

[0029] Preferably, the aryl group is phenyl, naphthyl, anthracenyl, phenanthrenyl or pyrenyl. Further preferably, the aryl group is phenyl or naphthyl.

[0030] For example, the heteroatom in the heteroaryl group is oxygen, sulfur or nitrogen.

[0031] Preferably, the heteroaryl group is a five-membered ring heteroaryl group, a six-membered ring heteroaryl group or a condensed ring heteroaryl group.

[0032] More preferably, the five-membered heteroaryl group is thienyl, pyrrolyl, furanyl, pyrazolyl, imidazolyl, oxazolyl, isoxazolyl or thiazolyl. More preferably, the five-membered heteroaryl group is thienyl, pyrrolyl, furanyl, pyrazolyl or imidazolyl.

[0033] More preferably, the six-membered heteroaryl group is pyridyl, pyranyl, pyrimidyl, pyrazinyl, pyridazinyl or triazinyl. More preferably, the six-membered heteroaryl group is pyridyl.

[0034] Further preferably, the condensed ring heteroaryl is carbazolyl, dibenzofuranyl, dibenzothienyl, indolyl, quinolyl, isoquinolyl, quinoxalinyl, benzofuranyl, benzothienyl, benzimidazolyl, pteridinyl, purinyl, acridinyl, phenazinyl or phenothiazinyl. More preferably, the condensed ring heteroaryl is carbazolyl, dibenzofuranyl or dibenzothienyl.

[0035] Preferably, the substituted aryl group is a substituted phenyl group or a substituted naphthyl group. Further preferably, the aryl group in the substituted aryl group is a substituted phenyl group.

[0036] Preferably, the substituted aryl group is fluorophenyl, fluoronaphthyl, C1~C6 straight chain or branched alkyl substituted phenyl, C1~C6 straight chain or branched alkyl substituted naphthyl, benzene substituted naphthyl, phenoxyphenyl, phenoxynaphthyl, C1~C5 alkoxy substituted phenyl or C1~C5 alkoxy substituted naphthyl.

[0037] More preferably, the C1~C5 alkoxy group is a C1~C5 straight-chain alkoxy group, a C3~C5 branched-chain alkoxy group or a C2~C5 cycloalkoxy group.

[0038] Further preferably, the substituted aryl group is , , , , , , , , , , , , , or .

[0039] Preferably, the substituted heteroaryl group is a fluorinated heteroaryl group or a C1-C5 straight-chain or branched alkyl substituted heteroaryl group.

[0040] Preferably, the substituted heteroaryl is a substituted five-membered ring heteroaryl, a substituted six-membered ring heteroaryl or a substituted condensed ring heteroaryl.

[0041] More preferably, the substituted five-membered heteroaryl group is a substituted thienyl group, a substituted pyrrolyl group, a substituted furanyl group, a substituted pyrazolyl group or a substituted imidazolyl group.

[0042] More preferably, the substituted six-membered ring heteroaryl is a substituted pyridyl.

[0043] Further preferably, the substituted condensed ring heteroaryl is a substituted benzofuranyl, a substituted indolyl, a substituted quinolyl, a substituted carbazolyl, a substituted dibenzofuranyl or a substituted dibenzothienyl; more preferably, the substituted condensed ring heteroaryl is a substituted carbazolyl, a substituted dibenzofuranyl or a substituted dibenzothienyl.

[0044] Preferably, the aryl vinyl group is phenyl vinyl group or naphthyl vinyl group. Further preferably, the aryl vinyl group is phenyl vinyl group.

[0045] Preferably, the heteroaryl vinyl group is a five-membered ring heteroaryl vinyl group, a six-membered ring heteroaryl vinyl group or a condensed ring heteroaryl vinyl group.

[0046] Preferably, the aryl ethynyl group is phenyl ethynyl or naphthyl ethynyl. Further preferably, the aryl ethynyl group is phenyl ethynyl.

[0047] Preferably, the heteroaryl ethynyl group is a five-membered ring heteroaryl ethynyl group, a six-membered ring heteroaryl ethynyl group or a condensed ring heteroaryl ethynyl group.

[0048] Preferably, the N,N-disubstituted arylamine is N,N-bisphenylamine, N,N-bisbiphenylamine, N,N-phenylbiphenylamine, N,N-phenylterphenylamine, N,N-bisterphenylamine or N,N-biphenylterphenylamine.

[0049] More preferably, the terphenyl in the N,N-disubstituted arylamine group is p-terphenyl.

[0050] In the present invention, R 1 The setting of the group can improve the solubility of the compound; R 2 and R 3 The arrangement of groups can adjust the position of absorption and emission spectra.

[0051] Preferably, the structural formula of Formula 1 includes at least one of the structures shown in Formula 2-1 to Formula 2-44:

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059] .

[0060] Preferably, the structural formula of Formula 1 includes at least one of the structures shown in Formula 3-1 to Formula 3-39:

[0061]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067] .

[0068] In a second aspect, the present invention provides a method for synthesizing the fluorescent compound containing triazole and benzofuran fused with a benzene ring, which has the structural formula of Formula 1 (Formula 2).

[0069] 1-1, when R 2 When it is hydrogen, fluorine or trifluoromethyl, the reaction equation is shown in Formula I, comprising the following steps:

[0070] 2-R 1 -4,7-dibromo-5,6-difluorobenzotriazole (specific structure see formula I) and 2-methoxy-4-substituted phenylboronic acid (specific structure see formula I) undergo coupling reaction, demethylation reaction is carried out under the action of boron tribromide, and then intramolecular ring closing reaction is carried out under the action of base to obtain a fluorescent compound containing triazole and benzofuran fused with a benzene ring;

[0071] In the formula, X is hydrogen or fluorine; R 1 Derived from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group.

[0072]

[0073] Formula I.

[0074] 1-2. When R 2 When it is hydrogen, fluorine or trifluoromethyl, the reaction equation is shown in Formula II, comprising the following steps:

[0075] 2-R 1 -4,7-dibromo-5,6-dimethoxybenzotriazole (specific structure see formula II) and 2-fluoro-4-substituted phenylboronic acid (specific structure see formula II) undergo coupling reaction, demethylation reaction is carried out under the action of boron tribromide, and then intramolecular ring closing reaction is carried out under the action of base to obtain a fluorescent compound containing triazole and benzofuran fused with a benzene ring;

[0076] In the formula, X is hydrogen or fluorine; R 1 Derived from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group.

[0077]

[0078] Formula II.

[0079] 2-1. When R 2When it is taken from an alkoxy group, the reaction equation is shown in Formula III, which includes the following steps:

[0080] 2-R 1 -4,7-dibromo-5,6-difluorobenzotriazole (specific structure see formula III) and 2,4-dimethoxy substituted phenylboronic acid (specific structure see formula III) are subjected to coupling reaction, followed by demethylation reaction under the action of boron tribromide, followed by intramolecular ring closure reaction under the action of a base, and then alkylation reaction to obtain a fluorescent compound containing triazole and benzofuran fused with a benzene ring;

[0081] In the formula, X is hydrogen or fluorine; R 1 Derived from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group.

[0082]

[0083] Formula III.

[0084] 2-2, when R 2 When it is taken from an alkoxy group, the reaction equation is shown in Formula IV, which includes the following steps:

[0085] 2-R 1 -4,7-dibromo-5,6-dimethoxybenzotriazole (specific structure see formula IV) and 2-fluoro-4-methoxy substituted phenylboronic acid (specific structure see formula IV) are subjected to coupling reaction, followed by demethylation reaction under the action of boron tribromide, followed by intramolecular ring closure reaction under the action of a base, and then alkylation reaction to obtain a fluorescent compound containing triazole and benzofuran fused with a benzene ring;

[0086] In the formula, X is hydrogen or fluorine; R 1 Derived from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group.

[0087]

[0088] Formula IV.

[0089] 3-1. When R 2 When it is selected from cyano, aryl, heteroaryl, substituted aryl, substituted heteroaryl, arylvinyl, heteroarylvinyl, arylethynyl, heteroarylethynyl or N,N-disubstituted arylamine, the reaction equation is shown in Formula V, comprising the following steps:

[0090] 2-R 1-4,7-dibromo-5,6-difluorobenzotriazole (specific structure see formula V) and 2,4-dimethoxy substituted phenylboronic acid (specific structure see formula V) undergo a first coupling reaction, then undergo a demethylation reaction under the action of boron tribromide, then undergo an intramolecular ring-closing reaction under the action of a base, and then undergo an esterification reaction, and the resulting trifluoromethanesulfonate undergoes a second coupling reaction to obtain a fluorescent compound containing triazole and benzofuran fused with a benzene ring;

[0091] In the formula, X is hydrogen or fluorine; R 1 Derived from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group.

[0092]

[0093] Formula V.

[0094] 3-2, when R 2 When it is selected from cyano, aryl, heteroaryl, substituted aryl, substituted heteroaryl, arylvinyl, heteroarylvinyl, arylethynyl, heteroarylethynyl or N,N-disubstituted arylamine, the reaction equation is shown in Formula VI, comprising the following steps:

[0095] 2-R 1 -4,7-dibromo-5,6-dimethoxybenzotriazole (specific structure is shown in Formula VI) and 2-fluoro-4-methoxy substituted phenylboronic acid (specific structure is shown in Formula VI) are subjected to a first coupling reaction, followed by a demethylation reaction under the action of boron tribromide, and then an intramolecular ring-closing reaction under the action of a base, followed by an esterification reaction, and the obtained trifluoromethanesulfonate is subjected to a second coupling reaction to obtain a fluorescent compound containing triazole and benzofuran fused with a benzene ring;

[0096] In the formula, X is hydrogen or fluorine; R 1 Derived from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group.

[0097]

[0098] Formula VI.

[0099] In a third aspect, the present invention provides a method for synthesizing the fluorescent compound containing triazole and benzofuran fused with a benzene ring, which has the structural formula of Formula 1 (Formula 3).

[0100] 1-1, when R 3 When it is hydrogen, fluorine or trifluoromethyl, the reaction equation is shown in Formula VII, comprising the following steps:

[0101] 2-R 1-4,7-dibromo-5,6-difluorobenzotriazole (specific structure see formula VII) and 2-methoxy-5-substituted phenylboronic acid (specific structure see formula VII) undergo coupling reaction, demethylation reaction is carried out under the action of boron tribromide, and then intramolecular ring closing reaction is carried out under the action of base to obtain a fluorescent compound containing triazole and benzofuran fused with a benzene ring;

[0102] In the formula, X is hydrogen or fluorine; R 1 Derived from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group.

[0103]

[0104] Formula VII.

[0105] 1-2. When R 3 When it is hydrogen, fluorine or trifluoromethyl, the reaction equation is shown in Formula VIII, comprising the following steps:

[0106] 2-R 1 -4,7-dibromo-5,6-dimethoxybenzotriazole (specific structure is shown in Formula VIII) and 2-fluoro-5-substituted phenylboronic acid (specific structure is shown in Formula VIII) are subjected to coupling reaction, demethylation reaction is carried out under the action of boron tribromide, and then intramolecular ring closing reaction is carried out under the action of base to obtain a fluorescent compound containing triazole and benzofuran fused with a benzene ring;

[0107] In the formula, X is hydrogen or fluorine; R 1 Derived from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group.

[0108]

[0109] Formula VIII.

[0110] 2-1. When R 3 When it is taken from an alkoxy group, the reaction equation is shown in Formula IX, which includes the following steps:

[0111] 2-R 1 -4,7-dibromo-5,6-difluorobenzotriazole (specific structure see formula IX) and 2,5-dimethoxy substituted phenylboronic acid (specific structure see formula IX) are subjected to coupling reaction, followed by demethylation reaction under the action of boron tribromide, followed by intramolecular ring closure reaction under the action of a base, and then alkylation reaction to obtain a fluorescent compound containing triazole and benzofuran fused with a benzene ring;

[0112] In the formula, X is hydrogen or fluorine; R 1 Derived from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group.

[0113]

[0114] Formula IX.

[0115] 2-2, when R 3 When it is taken from an alkoxy group, the reaction equation is shown in Formula X, which includes the following steps:

[0116] 2-R 1 -4,7-dibromo-5,6-dimethoxybenzotriazole (specific structure see formula X) and 2-fluoro-5-methoxy substituted phenylboronic acid (specific structure see formula X) undergo coupling reaction, then undergo demethylation reaction under the action of boron tribromide, then undergo intramolecular ring closure reaction under the action of base, and then undergo alkylation reaction to obtain a fluorescent compound containing triazole and benzofuran fused with a benzene ring;

[0117] In the formula, X is hydrogen or fluorine; R 1 Derived from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group.

[0118]

[0119] Formula X.

[0120] 3-1. When R 3 When it is selected from cyano, aryl, heteroaryl, substituted aryl, substituted heteroaryl, arylvinyl, heteroarylvinyl, arylethynyl, heteroarylethynyl or N,N-disubstituted arylamine, the reaction equation is shown in Formula XI, comprising the following steps:

[0121] 2-R 1 -4,7-dibromo-5,6-difluorobenzotriazole (specific structure shown in formula XI) and 2,5-dimethoxy substituted phenylboronic acid (specific structure shown in formula XI) undergo a first coupling reaction, then undergo a demethylation reaction under the action of boron tribromide, then undergo an intramolecular ring-closing reaction under the action of a base, and then undergo an esterification reaction, and the obtained trifluoromethanesulfonate undergoes a second coupling reaction to obtain a fluorescent compound containing triazole and benzofuran fused with a benzene ring;

[0122] In the formula, X is hydrogen or fluorine; R 1 Derived from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group.

[0123]

[0124] Formula XI.

[0125] 3-2, when R 3When it is selected from cyano, aryl, heteroaryl, substituted aryl, substituted heteroaryl, arylvinyl, heteroarylvinyl, arylethynyl, heteroarylethynyl or N,N-disubstituted arylamine, the reaction equation is shown in Formula XII, comprising the following steps:

[0126] 2-R 1 -4,7-dibromo-5,6-dimethoxybenzotriazole (specific structure is shown in Formula XII) and 2-fluoro-5-methoxy substituted phenylboronic acid (specific structure is shown in Formula XII) undergo a first coupling reaction, then undergo a demethylation reaction under the action of boron tribromide, then undergo an intramolecular ring-closing reaction under the action of a base, and then undergo an esterification reaction, and the obtained trifluoromethanesulfonate undergoes a second coupling reaction to obtain a fluorescent compound containing triazole and benzofuran fused with a benzene ring;

[0127] In the formula, X is hydrogen or fluorine; R 1 Derived from: C1~C18 alkyl or C1~C5 silyl with trimethylsilyl as terminal group.

[0128]

[0129] Formula XII.

[0130] The synthetic method of the fluorescent compound provided by the present invention is simple to operate, has good batch uniformity, is low in cost, and is suitable for large-scale production.

[0131] In a fourth aspect, the present invention provides a light conversion film comprising the above-mentioned fluorescent compound containing triazole and benzofuran fused with a benzene ring.

[0132] Preferably, the light-converting film comprises the following raw material components in parts by weight: 100 parts of a polymer matrix, 0.0005-1 parts of a fluorescent compound containing triazole and benzofuran fused with a benzene ring, 0.2-3 parts of a crosslinking agent, 0.1-3 parts of a crosslinking aid, 0.1-1 parts of a coupling agent, 0-0.2 parts of a light stabilizer and 0-0.2 parts of an antioxidant.

[0133] The light conversion film provided by the present invention uses a fluorescent compound as a single light conversion agent, and cooperates with other auxiliary materials to disperse the light conversion agent in a transparent polymer resin matrix. It has ideal optical properties and good light stability, and improves the sunlight collection efficiency and photoelectric conversion efficiency of solar cell modules; at the same time, it improves the power of solar cell modules, reduces the power attenuation of the modules after long-term UV irradiation, and prolongs the service life of photovoltaic modules; it can inhibit precipitation after long-term work in outdoor environments, and provide stable environmental protection for battery modules. The light conversion agent itself has excellent ultraviolet absorption capacity, and can efficiently convert ultraviolet light into a wavelength range that best matches the output power of crystalline silicon solar cells (such as heterojunction cells); and through further structural modification, the emission wavelength of the light conversion agent can also be adjusted to a wavelength range that is more suitable for the output power of perovskite solar cells.

[0134] Further preferably, the polymer matrix is ​​at least one of ethylene-vinyl acetate copolymer (EVA), polyvinyl butyral (PVB), polymethyl methacrylate (PMMA) or polyolefin elastomer (POE).

[0135] Further preferably, the cross-linking agent is at least one of tert-butyl peroxy-2-ethylhexyl carbonate (TBEC), tert-amyl peroxy-2-ethylhexyl carbonate (TAEC), tert-butyl peroxy-3,5,5-trimethylhexanoate (TBPIN), 2,5-di-tert-butylperoxy-2,5-dimethylhexane (BPDH), tert-butyl peroxy-2-ethylhexanoate (TBPO) or diisopropylbenzene peroxide (DCP).

[0136] Further preferably, the crosslinking aid is at least one of triallyl isocyanurate (TAIC) or trimethylolpropane triacrylate (TMPTA).

[0137] Further preferably, the coupling agent is at least one of γ-glycidyloxypropyltrimethoxysilane (KH-560), γ-aminopropyltriethoxysilane (KH-550), γ-methacryloxypropyltrimethoxysilane (KH-570), N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane (KH-792) or 3-(trimethoxysilyl)propyl methacrylate (Z-6030).

[0138] More preferably, the light stabilizer is 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole (UV-326), 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole (UV-327), 2-(2-hydroxy-3,5-di-tert-amylphenyl)benzotriazole (UV-328), polysuccinic acid (4-hydroxy-2,2,6,6-tetramethyl- At least one of bis(1-piperidinylethanol) ester (UV-622), bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (UV-770), bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate (UV-123), 3,5-di-tert-butyl-4-hydroxybenzoic acid hexadecyl ester (UV-2908) or 2-hydroxy-4-octyloxybenzophenone (UV-531).

[0139] More preferably, the antioxidant is at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (1010) or octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (1076).

[0140] More preferably, the thickness of the light conversion film is 100-1000 μm.

[0141] In a fifth aspect, the present invention provides a method for preparing a light conversion film, comprising the following steps:

[0142] Weigh the raw materials according to weight, mix the polymer matrix, the fluorescent compound containing triazole and benzofuran fused with benzene ring, the crosslinking agent, the crosslinking auxiliary agent, the coupling agent, the light stabilizer and the antioxidant evenly, melt extrude at 80-105° C., and cast to obtain a light conversion film.

[0143] It should be noted that if the light conversion film does not contain light stabilizers and antioxidants, they do not need to be added during mixing (only the polymer matrix, fluorescent compound, crosslinking agent, crosslinking aid and coupling agent are uniformly mixed).

[0144] In the present invention, the film can be formed by melt blending and casting, the film forming process is simple and efficient, and the light conversion film has stable performance, slow performance decay and long service life.

[0145] In a sixth aspect, the present invention also provides the use of the above-mentioned light conversion film in the preparation of photovoltaic modules.

[0146] Preferably, the photovoltaic module is a crystalline silicon heterojunction cell or a perovskite solar cell.

[0147] For example, the light conversion film is located between the cell and the glass before the incident light reaches the cell.

[0148] When the light conversion film of the present invention is used in the photovoltaic module of the heterojunction solar cell or the perovskite solar cell, the utilization efficiency of the module is further improved, which can not only significantly increase the power of the photovoltaic module and reduce the power attenuation of the module after long-term UV irradiation, but also extend the service life of the photovoltaic module. It can significantly improve the comprehensive performance of the solar cell module in many aspects and is superior to existing materials in relevant efficiency improvement indicators. DETAILED DESCRIPTION

[0149] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0150] In the examples and comparative examples of the present invention, if the specific conditions are not specified, the process is carried out according to conventional conditions or the conditions recommended by the manufacturer; if the manufacturer of the reagents or instruments is not specified, they are all conventional products that can be purchased from the market. The purity of the intermediates and the final products in the synthesis process and the detection of related impurities can be carried out by gas chromatograph GC or high performance liquid chromatograph HPLC. The models used in the present invention are Agilent 8890 GC and Agilent 1260II HPLC respectively; the structures of the intermediates or final products are determined by nuclear magnetic resonance hydrogen spectrum. 1 HNMR or carbon spectroscopy 13 CNMR for confirmation.

[0151] In the present invention, the UV-visible absorption spectrum and fluorescence emission spectrum of each synthesized fluorescent compound are tested by solution method, that is, the relevant fluorescent compound is dissolved in dichloromethane or tetrahydrofuran, and then tested by Q-6 UV-visible spectrophotometer (Shanghai METASH) and F7100 fluorescence spectrophotometer (Hitachi HITACHI). The fluorescence quantum yield of each fluorescent compound is tested by Horiba spectrometer FL-3, and the test is performed by integrating sphere at room temperature.

[0152] In order to better illustrate the present invention, further examples are given below.

[0153] Intermediate Synthesis Example 1

[0154] This intermediate synthesis example provides a method for synthesizing an intermediate having a structural formula shown in Formula 4, and the reaction equation is shown in Formula XIII.

[0155]

[0156] Formula XIII.

[0157] The specific steps include:

[0158] S1, add 147.60g (0.4mol) 2-isobutyl-4,7-dibromo-5,6-difluorobenzotriazole, 145.58g (0.8mol) 2,4-dimethoxyphenylboronic acid, 800mL toluene and 600mL ethanol into a 3L four-necked bottle, stir evenly, then add potassium carbonate solution (made up of 110.4g potassium carbonate and 400mL water), after evacuating the nitrogen, add 924.45mg (0.8mmol) tetrakistriphenylphosphine palladium in a nitrogen atmosphere, heat the system to reflux while stirring to react, take samples and monitor after 6h, monitor the 2-isobutyl After the basic reaction of -4,7-dibromo-5,6-difluorobenzotriazole was completed (residue <0.5%), the reaction system was cooled to room temperature, 800 mL of water was added, and the reaction system was allowed to stand for stratification; the water layer was extracted with toluene twice (400 mL×2), the toluene layers were combined, washed with water until neutral and dried, the toluene was concentrated under reduced pressure, 600 mL of ethanol was added, the temperature was raised to 75°C and stirred for 1 hour, then the temperature was lowered to -10°C for recrystallization, and after separation and drying, 174.07 g (0.36 mol) of the coupling intermediate (its specific structural formula is shown in Formula XIII) was obtained, the yield was 90.0%, and the purity was 99.61%.

[0159] S2, the above-mentioned coupling intermediate and 1.2L of dichloromethane are added to a 3L four-necked bottle, stirred evenly, cooled to -25°C under nitrogen protection, 450.94g (1.8mol) of boron tribromide is added dropwise while stirring, and the material temperature is kept not higher than -20°C. After 3h of dropping, the reaction is continued for 5h, and sampling is monitored. After the coupling intermediate is basically reacted completely (the residual amount is <0.2%), the reaction system is quenched in 3L of ice water and allowed to stand for stratification; the lower organic layer is taken, washed with water to neutrality, the dichloromethane is concentrated under reduced pressure, 200mL of n-heptane is added, and vacuum concentration is continued to remove the residual dichloromethane. After the residual dichloromethane is <2000ppm, 1.2L of DMF is added and mixed evenly to obtain a DMF solution containing the demethylation product intermediate (whose specific structural formula is shown in Formula XIII).

[0160] S3, the above-mentioned DMF solution containing the demethylation intermediate and 138.20g (1.0mol) of anhydrous potassium carbonate powder were added to a 3L four-necked bottle, stirred evenly, heated to 100°C under nitrogen protection for reaction, sampled and tested after 8h, and after HPLC monitoring, the demethylation product was basically reacted (the residual amount was <0.5%), the reaction system was cooled to below 40°C, filtered, the filter cake was rinsed with 300mL DMF, the DMF filtrate was combined, and the DMF was evaporated under reduced pressure; 500mL of toluene was added, heated to reflux and then cooled to -10°C for recrystallization, solid-liquid separation, and the filter cake was dried to obtain 116.22g (0.3mol) of the intermediate of the structure shown in formula 4. The combined yield of S2~S3 was 83.3%, and the purity was 99.76%.

[0161] Intermediate Synthesis Example 2

[0162] This intermediate synthesis example provides a method for synthesizing an intermediate having a structural formula as shown in Formula 5 (molecular weight is 651.51).

[0163]

[0164] Formula 5.

[0165] The specific steps include:

[0166] 116.22 g (0.3 mol) of the intermediate of the structure shown in Formula 4 prepared in Intermediate Synthesis Example 1, 1000 mL of dichloromethane and 101.19 g (1.0 mol) of triethylamine were added to a 3 L four-necked bottle and stirred evenly. 225.70 g (0.8 mol) of trifluoromethanesulfonic anhydride was added dropwise at -10~0°C. After 4~5 hours of addition, the reaction was continued by stirring for 12 hours. Sampling was performed for monitoring. After the intermediate of the structure shown in Formula 4 was basically reacted (the residual amount was <0.5%), the reaction system was placed in 1000 mL The mixture was quenched in 2.5 mol / L dilute hydrochloric acid and allowed to stand for stratification; the aqueous layer was extracted with 300 mL of dichloromethane, the organic layers (dichloromethane layers) were combined, washed with water until neutral, dried over magnesium sulfate, the desiccant (magnesium sulfate) was filtered out, and the filtrate was purified by passing through a silica gel column (30 g silica gel), the silica gel column was rinsed with 200 mL of dichloromethane, the column liquid was combined, and the solvent (dichloromethane) was evaporated under reduced pressure, and 100 mL of toluene was added and evaporated to dryness under reduced pressure to obtain 183.73 g (0.282 mol) of the intermediate of the structure shown in Formula 5, with a yield of 94.0% and a purity of 99.68%, which can be used for related synthesis.

[0167] Intermediate Synthesis Example 3

[0168] This intermediate synthesis example provides a method for synthesizing an intermediate having a structural formula shown in Formula 6, and the reaction equation is shown in Formula XIV.

[0169]

[0170] Formula XIV.

[0171] The specific steps include:

[0172] S1, 39.31g (0.1mol) 2-isobutyl-4,7-dibromo-5,6-dimethoxybenzotriazole, 29.38g (0.21mol) 2-fluorophenylboric acid, 350mL toluene and 200mL ethanol were added to a 1L four-necked bottle, stirred evenly, and then potassium carbonate solution (made of 34.5g potassium carbonate and 120mL water) was added. After nitrogen was evacuated, 231.11mg (0.2mmol) tetrakistriphenylphosphine palladium was added in a nitrogen atmosphere, and the system was heated to reflux while stirring for reaction. After 6h, sampling and monitoring were performed. GC was used to monitor the reaction of 2-isobutyl-4 After the basic reaction of 7-dibromo-5,6-dimethoxybenzotriazole is completed (the residual amount is less than 0.5%), the reaction system is cooled to room temperature, 300 mL of water is added, and the reaction system is allowed to stand for stratification; the water layer is extracted with toluene twice (100 mL×2), the toluene layers are combined, washed with water until neutral and dried, the toluene is concentrated under reduced pressure, 100 mL of ethanol is added, the temperature is raised to reflux, stirred and mixed, and then cooled to -10°C for recrystallization. After separation and drying, 38.96 g (92 mmol) of the coupling intermediate (its specific structural formula is shown in Formula XIV) are obtained, with a yield of 92.0% and a purity of 99.70%.

[0173] S2, the above-mentioned coupling intermediate and 400mL of dichloromethane are added to a 1L four-necked bottle, stirred evenly, cooled to -25°C under nitrogen protection, and 115.24g (0.46mol) of boron tribromide is added dropwise while stirring, keeping the material temperature not exceeding -20°C, and the reaction is continued for 5h after the addition is completed for 2h. Sampling is monitored, and after HPLC monitoring, the coupling intermediate is basically reacted completely (the residual amount is <0.2%), the reaction system is quenched in 800mL of ice water, and allowed to stand for stratification; the lower organic layer is taken, washed with water to neutrality, the dichloromethane is concentrated under reduced pressure, 100mL of n-heptane is added, and vacuum concentration is continued to remove the residual dichloromethane. After the residual dichloromethane is <2000ppm, 300mL of DMF is added and mixed evenly to obtain a DMF solution containing the demethylation product intermediate (whose specific structural formula is shown in Formula XIV).

[0174] S3, the above-mentioned DMF solution containing the demethylation intermediate and 41.46g (0.3mol) of anhydrous potassium carbonate powder were added to a 1L four-necked bottle, stirred evenly, heated to 100°C under nitrogen protection for reaction, sampled and tested after 8h, and HPLC monitored that the demethylation product was basically reacted (residual amount <0.5%), then the reaction system was cooled to below 40°C, filtered, the filter cake was rinsed with 100mL DMF, the DMF filtrate was combined, and the DMF was evaporated under reduced pressure; then 300mL of toluene was added, and the mixture was purified by a silica gel column (20g silica gel), and the column liquid was concentrated under reduced pressure to evaporate the solvent; then 150mL of ethanol was added, heated to reflux, stirred, cooled to -10°C, and solids were precipitated, solid-liquid separation was performed, and the filter cake was dried to obtain 28.08g (79mmol) of a fused ring compound intermediate (its specific structural formula is shown in Formula XIV), and the combined yield of S2~S3 was 85.9%, and the purity was 99.74%.

[0175] S4, add the above-mentioned fused ring compound intermediate, 2g iron powder and 300mL dichloromethane into a 1L four-necked bottle, mix well, add 31.96g (0.2mol) bromine dropwise at 10~20℃ (hydrogen bromide generated by the reaction is absorbed by an acidic gas absorption device), continue to stir and react for 3h after 1h~1.5h; then add 200mL 5wt% sodium bisulfite solution, let stand to separate layers; take the lower organic layer, wash with water to neutrality (300mL×3), concentrate dichloromethane under reduced pressure, add 120mL ethanol, raise the temperature to reflux, stir and mix well, cool to -10℃ for recrystallization, separate and dry, and obtain 34.90g (68mmol) of the intermediate with the structure shown in formula 6, with a yield of 86.1% and a purity of 99.77%, which can be used for related synthesis.

[0176] Example 1

[0177] This embodiment provides a fluorescent compound (Ia, molecular weight 619.81) containing triazole and benzofuran fused with a benzene ring.

[0178]

[0179] Ia.

[0180] The synthesis method of Ia above comprises the following steps:

[0181] 6.52 g (10 mmol) of the intermediate of the structure shown in Formula 5 prepared in Intermediate Synthesis Example 2, 3.74 g (21 mmol) of 4-tert-butylphenylboric acid, 100 mL of toluene and 80 mL of ethanol were added to a four-necked flask and stirred evenly. Potassium carbonate solution (prepared with 3.45 g of potassium carbonate and 30 mL of water) and 2.38 g (20 mmol) of potassium bromide were then added. After nitrogen was fully replaced, 115.56 mg (0.1 mmol) of tetrakistriphenylphosphine palladium was added. The system was heated to reflux while stirring to react. Sampling and monitoring were performed after 8 hours. After HPLC monitoring showed that the reaction was almost completely converted (residual amount <0.5%), the reaction system was cooled to room temperature and allowed to stand for stratification; the water layer was taken, 100 mL of toluene was added for extraction, the toluene layers were combined, washed with water until neutral, dried over magnesium sulfate, the desiccant was filtered out, and the filtrate was passed through a silica gel column (10 g silica gel) for purification, and the column liquid was concentrated under reduced pressure to evaporate the solvent; 100 mL of ethanol was added, and the mixture was heated to reflux and then cooled to -10°C with stirring to precipitate a solid, which was filtered and dried to obtain 5.21 g (8.4 mmol) of fluorescent compound Ia with a yield of 84% and a purity of 99.52%.

[0182] 1 H NMR (400 MHz, CDCl3) δ = 7.90 (dd, J = 7.9, 0.6 Hz, 2H), 7.84 (dd, J =2.1, 0.6 Hz, 2H), 7.65 (dd, J = 7.9, 2.1 Hz, 2H), 7.54 – 7.46 (m, 4H), 7.37 (d, J = 6.8 Hz, 4H), 3.79 (d, J = 4.4 Hz, 2H), 2.28 – 2.14 (m, 1H), 1.34 (s, 18H), 1.02 (d, J = 7.4 Hz, 6H).

[0183] Example 2

[0184] This embodiment provides a fluorescent compound (Ib, molecular weight 567.64) containing triazole and benzofuran fused with a benzene ring.

[0185]

[0186] Ib.

[0187] The synthesis method of Ib is similar to that of Ia, except that 4-tert-butylphenylboronic acid is replaced with an equal molar amount of 4-methoxyphenylboronic acid, and the remaining steps are the same as those in Example 1, which will not be repeated. Finally, 4.60 g (8.1 mmol) of fluorescent compound Ib was obtained, with a yield of 81% and a purity of 99.61%.

[0188] 1 H NMR (400 MHz, CDCl3) δ = 7.90 (dd, J = 7.9, 0.6 Hz, 2H), 7.78 – 7.73(m, 2H), 7.65 (dd, J = 7.9, 2.1 Hz, 2H), 7.57 – 7.50 (m, 4H), 7.01 – 6.94 (m,4H), 3.84 – 3.76 (m, 8H), 2.21 (m, 1H), 1.02 (d, J = 7.4 Hz, 6H).

[0189] Example 3

[0190] This embodiment provides a fluorescent compound (Ic, molecular weight 443.50) containing triazole and benzofuran fused with a benzene ring.

[0191]

[0192] Ic.

[0193] The synthesis method of Ic comprises the following steps:

[0194] 19.37 g (50 mmol) of the intermediate of the structure shown in formula 4 prepared in Intermediate Synthesis Example 1 and 200 mL of DMF were added to a four-necked bottle, 27.64 g (200 mmol) of anhydrous potassium carbonate was added while stirring, and then 32.69 g (300 mol) of ethyl bromide was added. After reacting at 65° C. for 12 h, sampling was performed for monitoring. After HPLC monitoring showed that the reaction was basically completely converted (residual amount <0.5%), the reaction system was cooled to below 40° C., filtered, the filter cake was rinsed with 50 mL of DMF, the DMF filtrate was combined, and the DMF was evaporated under reduced pressure; 300 mL of toluene was added, mixed evenly, and purified by passing through a silica gel column (15 g of silica gel), the column liquid was concentrated under reduced pressure to evaporate toluene, and then 200 mL of ethanol was added, the temperature was raised to reflux, stirred and mixed, and then cooled to -10° C. for recrystallization, suction filtered, and dried to obtain 19.96 g (45 mmol) of fluorescent compound Ic, with a yield of 90% and a purity of 99.86%.

[0195] 1H NMR (400 MHz, CDCl3) δ 7.75 (d, J = 8.2 Hz, 2H), 7.23 (dd, J = 2.1, 0.6Hz, 2H), 6.80 (dd, J = 8.3, 2.1 Hz, 2H), 4.03 (q, J = 6.7 Hz, 4H), 3.79 (d, J = 4.4Hz, 2H), 2.28 – 2.14 (m, 1H), 1.43 (t, J = 6.7 Hz, 6H), 1.02 (d, J = 7.4 Hz, 6H).

[0196] Example 4

[0197] This embodiment provides a fluorescent compound (Id, molecular weight 689.82) containing triazole and benzofuran fused with a benzene ring.

[0198]

[0199] Id.

[0200] The synthesis method of the above-mentioned Id comprises the following steps:

[0201] 6.52 g (10 mmol) of the intermediate of the structure shown in Formula 5 prepared in Intermediate Synthesis Example 2, 3.55 g (21 mmol) of diphenylamine, 200 mL of toluene, 5.61 g (50 mmol) of potassium tert-butoxide and 0.24 g (0.4 mmol) of Pd(dppp)Cl2 were added into a four-necked flask fully replaced with nitrogen, mixed evenly, and the system was heated to reflux while stirring to react. After 10 hours, sampling and monitoring were performed. HPLC monitoring showed that the reaction was basically completely converted. (residual amount <0.5%), the reaction system was cooled to room temperature, 200 mL of water was added, and the reaction system was allowed to stand for stratification; the toluene layer was washed with water until neutral, dried over magnesium sulfate, the desiccant was filtered out, and the filtrate was purified by passing through a silica gel column (10 g of silica gel), and the column liquid was concentrated under reduced pressure to evaporate the solvent; 120 mL of ethanol was added, and the mixture was heated to reflux and then cooled to -10°C with stirring to precipitate a solid, which was filtered and dried to obtain 5.79 g (8.4 mmol) of fluorescent compound Id with a yield of 84% and a purity of 99.41%.

[0202] 1 H NMR δ 8.09 (d, J= 7.3 Hz, 2H), 7.65 – 7.60 (m, 2H), 7.33 – 7.24 (m,8H), 7.15 – 6.99 (m, 14H), 3.79 (d, J = 4.4 Hz, 2H), 2.21 (m, 1H), 1.02 (d, J =7.4 Hz, 6H).

[0203] Example 5

[0204] This embodiment provides a fluorescent compound (Ie, molecular weight 491.39) containing triazole and benzofuran fused with a benzene ring.

[0205]

[0206] Formula XV.

[0207] The synthesis method of the above-mentioned Ie comprises the following steps (the reaction equation is shown in Formula XV):

[0208] S1, add 15.72g (40mmol) 2-butyl-4,7-dibromo-5,6-dimethoxybenzotriazole, 16.63g (80mmol) 2-fluoro-4-trifluoromethylphenylboric acid, 100mL toluene and 80mL ethanol into a four-necked bottle, stir evenly, then add potassium carbonate solution (made up of 11.04g potassium carbonate and 50mL water), after nitrogen is evacuated, add 92.44mg (0.08mmol) tetrakistriphenylphosphine palladium in a nitrogen atmosphere, heat the system to reflux while stirring to react, take samples and monitor after 6h, monitor 2 After the basic reaction of -butyl-4,7-dibromo-5,6-dimethoxybenzotriazole is completed (residue < 0.5%), the reaction system is cooled to room temperature, 100 mL of water is added, and the reaction system is allowed to stand for stratification; the water layer is extracted with 100 mL of toluene, the toluene layers are combined, washed with water until neutral and dried, the toluene is concentrated under reduced pressure, 150 mL of ethanol is added, the temperature is raised to reflux, stirred and mixed, and then the temperature is lowered to -10°C for recrystallization. After separation and drying, 20.14 g (36 mmol) of a coupling intermediate (its specific structural formula is shown in Formula XV) is obtained, with a yield of 90% and a purity of 99.66%.

[0209] S2, the above-mentioned coupling intermediate and 220mL of dichloromethane are added to a four-necked bottle, stirred evenly, cooled to -25°C under nitrogen protection, 45.09g (0.18mol) of boron tribromide is added dropwise while stirring, and the material temperature is kept not higher than -20°C. After 1h of dropping, the reaction is continued for 5h, and sampling is monitored. After the coupling intermediate is basically reacted completely (the residual amount is <0.2%), the reaction system is quenched in 500mL of ice water and allowed to stand for stratification; the lower organic layer is taken, washed with water until neutral, the dichloromethane is concentrated under reduced pressure, 50mL of n-heptane is added, and vacuum concentration is continued to remove the residual dichloromethane. After the residual dichloromethane is <2000ppm, 150mL of DMF is added and mixed evenly to obtain a DMF solution containing the demethylation product intermediate (whose specific structural formula is shown in Formula XV).

[0210] S3, the above-mentioned DMF solution containing the demethylation intermediate and 13.82g (0.10mol) of anhydrous potassium carbonate powder were added to a four-necked bottle, stirred evenly, heated to 100°C under nitrogen protection for reaction, sampled and tested after 8h, and after HPLC monitoring, the demethylation product was basically reacted (the residual amount was <0.2%), the reaction system was cooled to below 40°C, filtered, the filter cake was rinsed with 50mL DMF, the DMF filtrate was combined, and the DMF was evaporated under reduced pressure; then 150mL of toluene was added, and the mixture was purified by passing through a silica gel column (10g silica gel), and the column liquid was concentrated under reduced pressure to evaporate the solvent; then 100mL of ethanol was added, heated to reflux, stirred, cooled to -10°C, and solids were precipitated, solid-liquid separation was performed, and the filter cake was dried to obtain 15.04g (30.6mmol) of fluorescent compound Ie. The combined yield of S2~S3 was 85%, and the purity was 99.72%.

[0211] 1 H NMR δ 8.05 (d, J = 10.8 Hz, 1H), 7.80 (dd, J = 2.1, 0.7 Hz, 1H), 7.60(dd, J = 10.8, 2.1 Hz, 1H), 4.24 (t, J = 5.7 Hz, 1H), 1.88 (tt, J = 7.1, 5.6 Hz,1H), 1.45 (dt, J = 13.9, 7.0 Hz, 1H), 0.94 (t, J = 6.8 Hz, 2H).

[0212] Example 6

[0213] This embodiment provides a fluorescent compound (If, molecular weight 555.64) containing triazole and benzofuran fused with a benzene ring.

[0214]

[0215] If.

[0216] The synthesis method of If comprises the following steps:

[0217] 6.52 g (10 mmol) of the intermediate of the structure shown in Formula 5 prepared in Intermediate Synthesis Example 2, 100 mL of toluene and 20 mL of triethylamine were added to a four-necked bottle and stirred evenly. Then, 0.19 g (1 mmol) of cuprous iodide and 11.56 mg (0.1 mmol) of tetrakistriphenylphosphine palladium were added. After nitrogen was fully replaced, the system was heated to 50°C, and 20 mL of a toluene solution containing 2.14 g (21 mmol) of phenylacetylene was added dropwise while stirring. After 15 minutes of dropping, the temperature was raised to 75°C and the reaction was continued with stirring for 8 hours. Sampling was performed for monitoring. The reaction was basically completely converted by HPLC monitoring ( After the reaction mixture was purified by a silica gel column (10 g silica gel), the column liquid was concentrated under reduced pressure to evaporate the solvent; 100 mL of ethanol was added, the mixture was heated to reflux, and the temperature was lowered to -10 °C with stirring to precipitate a solid, which was then filtered and dried to obtain 5.06 g (9.1 mmol) of a fluorescent compound If with a yield of 91% and a purity of 99.52%.

[0218] 1 H NMR (400 MHz, CDCl3) δ 8.07 (dd, J = 7.0, 0.6 Hz, 2H), 7.77 (d, J = 2.1Hz, 2H), 7.68 – 7.58 (m, 4H), 7.54 (dd, J = 7.0, 2.1 Hz, 2H), 7.40 – 7.30 (m,6H), 3.79 (d, J = 4.4 Hz, 2H), 2.21 (m, 1H), 1.02 (d, J = 7.4 Hz, 6H).

[0219] Example 7

[0220] This embodiment provides a fluorescent compound (Ig, molecular weight 419.43) containing triazole and benzofuran fused with a benzene ring.

[0221]

[0222] Formula XVI.

[0223] The synthesis method of the above Ig comprises the following steps (see reaction equation XVI):

[0224] S1, add 39.71g (0.1mol) 2-n-hexyl-4,7-dibromo-5,6-difluorobenzotriazole, 35.69g (0.21mol) 5-fluoro-2-methoxyphenylboronic acid, 300mL toluene and 150mL ethanol into a four-necked bottle, stir evenly, then add potassium carbonate solution (made up of 34.5g potassium carbonate and 100mL water), after evacuating the nitrogen, add 231.11mg (0.2mmol) tetrakistriphenylphosphine palladium in a nitrogen atmosphere, heat the system to reflux while stirring to react, take samples and monitor after 6h, monitor the 2-n-hexyl-4,7-dibromo-5,6-difluorobenzotriazole by GC. After the basic reaction of 4,7-dibromo-5,6-difluorobenzotriazole was completed (residue < 0.5%), the reaction system was cooled to room temperature, 300 mL of water was added, and the reaction system was allowed to stand for stratification; the water layer was extracted with toluene twice (100 mL × 2), the toluene layers were combined, washed with water until neutral and dried, the toluene was concentrated under reduced pressure, 150 mL of ethanol was added, the temperature was raised to reflux, stirred and mixed, and then the temperature was lowered to -10°C for recrystallization. After separation and drying, 43.88 g (90 mmol) of the coupling intermediate (its specific structural formula is shown in Formula XVI) was obtained, with a yield of 90% and a purity of 99.49%.

[0225] S2, the above-mentioned coupling intermediate and 300mL of dichloromethane are added to a four-necked bottle, stirred evenly, cooled to -25°C under nitrogen protection, and 112.73g (0.45mol) of boron tribromide is added dropwise while stirring, keeping the material temperature not exceeding -20°C, and the reaction is continued for 5h after the addition is completed for 2h. Sampling is monitored, and after HPLC monitoring, the coupling intermediate is basically reacted completely (the residual amount is <0.2%), the reaction system is quenched in 1L of ice water, and allowed to stand for stratification; the lower organic layer is taken, washed with water to neutrality, the dichloromethane is concentrated under reduced pressure, 100mL of n-heptane is added, and vacuum concentration is continued to remove the residual dichloromethane. After the residual dichloromethane is <2000ppm, 250mL of DMF is added and mixed evenly to obtain a DMF solution containing the demethylation product intermediate (whose specific structural formula is shown in Formula XVI).

[0226] S3, the above-mentioned DMF solution containing the demethylation intermediate and 41.46g (0.3mol) of anhydrous potassium carbonate powder were added to a four-necked bottle, stirred evenly, heated to 100°C under nitrogen protection for reaction, sampled and tested after 8h, and HPLC monitored that the demethylation product was basically reacted (residual amount <0.2%), then the reaction system was cooled to below 40°C, filtered, the filter cake was rinsed with 50mL DMF, the DMF filtrate was combined, and the DMF was evaporated under reduced pressure; then 300mL of toluene was added, and the mixture was purified by passing through a silica gel column (20g silica gel), and the column liquid was concentrated under reduced pressure to evaporate the solvent; then 120mL of ethanol was added, heated to reflux, stirred, cooled to -10°C, solid was precipitated, solid-liquid separation was performed, and the filter cake was dried to obtain 34.81g (0.083mol) of fluorescent compound Ig. The combined yield of S2~S3 was 92.2%, and the purity was 99.80%.

[0227] 1 H NMR (400 MHz, CDCl3) δ 7.73 (dd, J = 8.0, 2.6 Hz, 1H), 7.61 (dd, J =8.2, 5.1 Hz, 1H), 7.19 (td, J = 8.1, 2.6 Hz, 1H), 4.23 (t, J = 5.3 Hz, 1H), 1.87(tt, J = 7.4, 5.3 Hz, 1H), 1.47 – 1.39 (m, 1H), 1.39 – 1.25 (m, 2H), 0.93 –0.85 (m, 2H).

[0228] Example 8

[0229] This embodiment provides a fluorescent compound (Ih, molecular weight 619.81) containing triazole and benzofuran fused with a benzene ring.

[0230]

[0231] Ih.

[0232] The synthetic method of above-mentioned Ih comprises the steps:

[0233] 34.90 g (68 mmol) of the intermediate of the structure shown in Formula 6 prepared in Intermediate Synthesis Example 3, 24.93 g (140 mmol) of 4-tert-butylphenylboric acid, 300 mL of toluene and 250 mL of ethanol were added to a four-necked bottle and stirred evenly. Potassium carbonate solution (prepared from 27.6 g of potassium carbonate and 200 mL of water) was then added. After nitrogen was evacuated, 161.78 mg (0.14 mmol) of tetrakistriphenylphosphine palladium was added in a nitrogen atmosphere. The system was heated to reflux while stirring for reaction. Sampling was performed after 8 h for monitoring by HPLC. After monitoring that the reaction was basically completely converted (residual amount <0.2%), the reaction system was cooled to room temperature and allowed to stand for stratification; the water layer was taken, 300 mL of toluene was added for extraction, the toluene layers were combined, washed with water until neutral, dried over magnesium sulfate, the desiccant was filtered out, and the filtrate was purified by passing through a silica gel column (20 g silica gel), and the column liquid was concentrated under reduced pressure to evaporate the solvent; 100 mL of ethanol was added, and the mixture was heated to reflux and then cooled to -10°C with stirring to precipitate a solid, which was filtered and dried to obtain 37.81 g (61 mmol) of fluorescent compound Ih with a yield of 89.7% and a purity of 99.65%.

[0234] 1 H NMR (400 MHz, CDCl3) δ 8.25 – 8.20 (m, 2H), 7.69 (dd, J = 7.2, 2.1Hz, 2H), 7.60 (d, J = 7.3 Hz, 2H), 7.55 – 7.47 (m, 4H), 7.42 – 7.35 (m, 4H), 3.79 (d, J = 4.4 Hz, 2H), 2.20 (m, 1H), 1.34 (s, 18H), 1.02 (d, J = 7.4 Hz, 6H).

[0235] Example 9

[0236] This embodiment provides a fluorescent compound (Ii, molecular weight 529.55) containing triazole and benzofuran fused with a benzene ring.

[0237]

[0238] Formula XVII.

[0239] The synthesis method of Ii comprises the following steps (see reaction equation XVII):

[0240] S1 is similar to Intermediate Synthesis Example 3, except that 2-isobutyl-4,7-dibromo-5,6-dimethoxybenzotriazole is replaced by an equal molar amount of 2-methyl-4,7-dibromo-5,6-dimethoxybenzotriazole, and 2-fluorophenylboric acid is replaced by an equal molar amount of 2,3-difluorophenylboric acid. The remaining steps are the same as S1 of Intermediate Synthesis Example 3, and will not be repeated. 37.98 g (91 mmol) of the coupling intermediate (its specific structural formula is shown in Formula XVII) is obtained, with a yield of 91% and a purity of 99.64%.

[0241] S2 is the same as S2 in Intermediate Synthesis Example 3, and is not described again. A DMF solution containing a demethylation product intermediate (whose specific structural formula is shown in Formula XVII) is obtained.

[0242] S3 is the same as S3 in Intermediate Synthesis Example 3, and is not described again. 27.94 g (80 mmol) of a condensed ring compound intermediate (its specific structural formula is shown in Formula XVII) was obtained, and the combined yield of S2 to S3 was 87.9%, and the purity was 99.59%.

[0243] S4 is the same as S4 in Intermediate Synthesis Example 3, and is not described again. 36.00 g (71 mmol) of a dibromo intermediate (its specific structural formula is shown in Formula XVII) was obtained with a yield of 88.8% and a purity of 99.62%.

[0244] S5 is similar to Example 8, except that 24.92 g (140 mmol) of 4-tert-butylphenylboronic acid is replaced with 19.71 g (145 mmol) of 4-methylphenylboronic acid. The remaining steps are the same as those in Example 8 and will not be repeated here. Finally, 33.36 g (63 mmol) of fluorescent compound Ii is obtained, with a yield of 88.7% and a purity of 99.71%.

[0245] 1 H NMR (400 MHz, CDCl3) δ 7.97 (d, J = 2.2 Hz, 2H), 7.62 – 7.52 (m, 6H), 7.25 (m, 4H), 4.45 (s, 3H), 2.40 (d, J = 1.4 Hz, 6H).

[0246] Example 10

[0247] This embodiment provides a fluorescent compound (Ij, molecular weight 685.79) containing triazole and benzofuran fused with a benzene ring.

[0248]

[0249] Ij.

[0250] The synthetic method of above-mentioned Ij comprises the steps:

[0251] 34.90 g (68 mmol) of the intermediate of the structure shown in Formula 6 prepared in Intermediate Synthesis Example 3, 23.41 g (140 mmol) of carbazole, 400 mL of toluene, 44.88 g (400 mmol) of potassium tert-butoxide and 0.24 g (0.4 mmol) of Pd(dppp)Cl2 were added into a four-necked bottle fully replaced with nitrogen, mixed evenly, and the system was heated to reflux while stirring to react. After 8 hours, sampling was performed for monitoring. After the reaction was basically completely converted (residue <0.2%), HPLC monitoring was performed. The reaction system was cooled to room temperature, 400 mL of water was added, and the mixture was stirred for 1 h and then allowed to stand to separate into layers; the water layer was taken and 600 mL of toluene was added for extraction, the toluene layers were combined, washed with water until neutral, dried over magnesium sulfate, the desiccant was filtered out, and the filtrate was passed through a silica gel column (20 g of silica gel) for purification, and the column liquid was concentrated under reduced pressure to evaporate the solvent; 300 mL of ethanol was then added, and the mixture was heated to reflux and then cooled to -10°C with stirring to precipitate a solid, which was filtered and dried to obtain 40.46 g (59 mmol) of fluorescent compound Ij with a yield of 86.8% and a purity of 99.48%.

[0252] 1 H NMR δ 8.19 – 8.09 (m, 4H), 8.02 (dd, J = 1.6, 1.0 Hz, 2H), 7.69 –7.61 (m, 4H), 7.57 – 7.49 (m, 4H), 7.40 – 7.26 (m, 8H), 3.79 (d, J = 4.4 Hz,2H), 2.21 (m, 1H), 1.02 (d, J = 7.4 Hz, 6H).

[0253] Embodiment 11

[0254] This embodiment provides a fluorescent compound (Ik, molecular weight 565.68) containing triazole and benzofuran fused with a benzene ring.

[0255]

[0256] Formula XVIII.

[0257] The synthesis method of Ik comprises the following steps (see reaction equation XVIII):

[0258] S1 is similar to Intermediate Synthesis Example 1, except that 2-isobutyl-4,7-dibromo-5,6-difluorobenzotriazole is replaced with an equal molar amount of 2-n-octyl-4,7-dibromo-5,6-difluorobenzotriazole, and the remaining steps are the same as S1 of Intermediate Synthesis Example 1, which will not be repeated. 188.87 g (0.35 mol) of the coupling intermediate (its specific structural formula is shown in Formula XVIII) is obtained, with a yield of 87.5% and a purity of 99.49%.

[0259] S2 is the same as S2 in Intermediate Synthesis Example 1 and will not be described again. A DMF solution containing a demethylation product intermediate (whose specific structural formula is shown in Formula XVIII) is obtained.

[0260] S3 is the same as S3 in Intermediate Synthesis Example 1, and is not described again. 133.05 g (0.3 mol) of a condensed ring compound intermediate (its specific structural formula is shown in Formula XVIII) was obtained, and the combined yield of S2 to S3 was 85.7%, and the purity was 99.70%.

[0261] S4 is the same as in Intermediate Synthesis Example 2, which will not be described in detail. 183.98 g (0.26 mol) of bistrifluoromethanesulfonic acid intermediate (its specific structural formula is shown in Formula XVIII) was obtained, with a yield of 86.7% and a purity of 99.61%.

[0262] S5, 7.08g (10mmol) of the above-mentioned bistrifluoromethanesulfonic acid intermediate, 2.58g (21mmol) of pyridine-3-boric acid, 100mL of toluene and 80mL of ethanol were added to a four-necked bottle and stirred evenly, and then potassium carbonate solution (prepared with 3.45g of potassium carbonate and 30mL of water) and 2.38g (20mmol) of potassium bromide were added. After nitrogen was fully replaced, 115.56mg (0.1mmol) of tetrakistriphenylphosphine palladium was added, and the system was heated to reflux while stirring to react. After 10h, sampling was carried out for monitoring by HPLC. After the reaction was monitored to be substantially completely converted (residual amount <0.2%), the reaction system was cooled to room temperature and allowed to stand for stratification; the aqueous layer was extracted with 100 mL of toluene, the toluene layers were combined, washed with water until neutral, dried over magnesium sulfate, the desiccant was filtered out, the filtrate was purified by passing through a silica gel column (10 g silica gel), and the column liquid was concentrated under reduced pressure to evaporate the solvent; 100 mL of ethanol was then added, the mixture was heated to reflux, and then cooled to -10°C with stirring to precipitate a solid, which was filtered and dried to obtain 4.86 g (8.6 mmol) of fluorescent compound Ik with a yield of 86% and a purity of 99.55%.

[0263] 1 H NMR (400 MHz, CDCl3) δ 8.86 (q, J = 1.1 Hz, 2H), 8.65 (m, 2H), 7.94(m, 4H), 7.78 (d, J= 2.0 Hz, 2H), 7.53 (dd, J = 7.9, 2.1 Hz, 2H), 7.33 (dd, J =7.6, 4.9 Hz, 2H), 4.23 (t, J = 5.3 Hz, 2H), 1.88 (tt, J = 7.8, 5.4 Hz, 2H), 1.45–1.33 (m, 2H), 1.33–1.23 (m, 8H), 1.03–0.73 (m, 3H).

[0264] Example 12

[0265] This embodiment provides a fluorescent compound (I1, molecular weight 519.64) containing triazole and benzofuran fused with a benzene ring.

[0266]

[0267] Il.

[0268] The synthesis method of Il is similar to that of Example 1, except that 4-tert-butylphenylboronic acid is replaced with an equal molar amount of 2-thiopheneboronic acid, and the remaining steps are the same as S1 of Intermediate Synthesis Example 1, which will not be repeated. Finally, 4.42 g (8.5 mmol) of fluorescent compound Il was obtained, with a yield of 85% and a purity of 99.61%.

[0269] 1 H NMR (400 MHz, CDCl3) δ 7.93 (d, J = 7.6 Hz, 2H), 7.81 – 7.75 (m, 2H), 7.65 (dd, J = 7.8, 2.1 Hz, 2H), 7.59 (dd, J = 5.0, 1.7 Hz, 2H), 7.53 (dd, J = 6.1,1.7 Hz, 2H), 7.17 (dd, J = 6.1, 5.0 Hz, 2H), 3.79 (d, J = 4.4 Hz, 2H), 2.21 (m,1H), 1.02 (d, J = 7.4 Hz, 6H).

[0270] Example 13

[0271] This embodiment provides a fluorescent compound (Im, molecular weight 637.81) containing triazole and benzofuran fused with a benzene ring.

[0272]

[0273] Formula XIX.

[0274] The synthesis method of the above Im comprises the following steps (see the reaction equation XIX):

[0275] S1 is similar to Intermediate Synthesis Example 1, except that 2-isobutyl-4,7-dibromo-5,6-difluorobenzotriazole is replaced by an equal molar amount of 2-trimethylsilylmethyl-4,7-dibromo-5,6-difluorobenzotriazole (which can be prepared by conventional methods, and its preparation method is not repeated here), and the remaining steps are the same as S1 of Intermediate Synthesis Example 1, and are not repeated here. 184.90 g (0.36 mol) of the coupling intermediate (its specific structural formula is shown in Formula XIX) is obtained, with a yield of 90% and a purity of 99.54%.

[0276] S2 is the same as S2 in Intermediate Synthesis Example 1 and is not described again. A DMF solution containing a demethylation product intermediate (whose specific structural formula is shown in Formula XIX) is obtained.

[0277] S3 is the same as S3 in Intermediate Synthesis Example 1, and is not described again. 107.80 g (0.3 mol) of a condensed ring compound intermediate (its specific structural formula is shown in Formula XIX) was obtained, and the combined yield of S2 to S3 was 83.3%, and the purity was 99.61%.

[0278] S4, the same as the intermediate synthesis example 2, no further description is given. 163.59 g (0.24 mol) of the bistrifluoromethanesulfonic acid intermediate (its specific structural formula is shown in Formula XIX) was obtained, with a yield of 80% and a purity of 99.64%.

[0279] S5, 6.82g (10mmol) of the above-mentioned bistrifluoromethanesulfonic acid intermediate, 3.61g (21mmol) of 2-naphthaleneboronic acid, 50mL of toluene and 40mL of ethanol were added to a four-necked bottle and stirred evenly, and then potassium carbonate solution (prepared by 3.45g of potassium carbonate and 10mL of water) and 2.38g (20mmol) of potassium bromide were added. After nitrogen was fully replaced, 115.56mg (0.1mmol) of tetrakistriphenylphosphine palladium was added, and the system was heated to reflux while stirring to react. After 10h, sampling was carried out for monitoring, and HPLC was used. After monitoring that the reaction was basically completely converted (residual amount <0.2%), the reaction system was cooled to room temperature and allowed to stand for stratification; the water layer was taken, 50 mL of toluene was added for extraction, the toluene layers were combined, washed with water until neutral, dried over magnesium sulfate, the desiccant was filtered out, and the filtrate was purified by passing through a silica gel column (5 g silica gel), and the column liquid was concentrated under reduced pressure to evaporate the solvent; 40 mL of ethanol was added, and the mixture was heated to reflux and then cooled to -10°C with stirring to precipitate a solid, which was filtered and dried to obtain 5.61 g (8.8 mmol) of the fluorescent compound Im, with a yield of 88% and a purity of 99.58%.

[0280] 1 H NMR (400 MHz, CDCl3) δ 8.05 (t, J = 2.0 Hz, 2H), 7.98 (dd, J = 7.7, 2.4Hz, 4H), 7.95 – 7.88 (m, 4H), 7.79 (d, J = 2.1 Hz, 2H), 7.72 (dd, J = 8.1, 2.1Hz, 2H), 7.58 – 7.47 (m, 6H), 3.22 (s, 2H), 0.13 (s, 9H).

[0281] Embodiment 14

[0282] This embodiment provides a fluorescent compound (In, molecular weight 687.75) containing triazole and benzofuran fused with a benzene ring.

[0283]

[0284] In.

[0285] The above-mentioned synthesis method of In comprises the following steps:

[0286] 34.90 g (68 mmol) of the intermediate of the structure shown in Formula 6 prepared in Intermediate Synthesis Example 3, 29.68 g (140 mmol) of dibenzofuran-2-boric acid, 300 mL of toluene and 250 mL of ethanol were added to a four-necked bottle and stirred evenly. Potassium carbonate solution (prepared from 27.6 g of potassium carbonate and 200 mL of water) was then added. After the nitrogen was evacuated, 161.78 mg (0.14 mmol) of tetrakistriphenylphosphine palladium was added in a nitrogen atmosphere. The system was heated to reflux while stirring for reaction. After 8 hours, sampling and monitoring were performed. HPL After the reaction was basically completely converted (residue < 0.2%) as monitored by C, the reaction system was cooled to room temperature and allowed to stand for stratification; the water layer was extracted with 400 mL of toluene, the toluene layers were combined, washed with water until neutral, dried over magnesium sulfate, the desiccant was filtered out, and the filtrate was purified by passing through a silica gel column (25 g silica gel), and the column liquid was concentrated under reduced pressure to evaporate the solvent; 150 mL of ethanol was added, and the mixture was heated to reflux and then cooled to -10°C with stirring to precipitate a solid, which was filtered and dried to obtain 42.64 g (62 mmol) of the fluorescent compound In, with a yield of 91.2% and a purity of 99.65%.

[0287] 1 H NMR (400 MHz, CDCl3) δ 8.21 (d, J = 2.1 Hz, 2H), 8.13 (d, J = 2.1 Hz,2H), 8.06 – 7.99 (m, 2H), 7.7 – 7.63 (m, 4H), 7.63 – 7.56 (m, 4H), 7.56 –7.52 (m, 2H), 7.5 – 7.46 (m, 2H), 7.42 – 7.33 (m, 2H), 3.79 (d, J = 4.3 Hz,2H), 2.15 – 2.25 (m, 1H), 1.02 (d, J = 7.4 Hz, 6H).

[0288] Embodiment 15

[0289] This embodiment provides a fluorescent compound (Io, molecular weight 719.88) containing triazole and benzofuran fused with a benzene ring.

[0290]

[0291] Io.

[0292] The synthesis method of Io is similar to that of Example 8, except that 4-tert-butylphenylboronic acid is replaced with an equal molar amount of dibenzothiophene-1-boric acid, and the remaining steps are the same as those of Example 8 and will not be repeated. Finally, 43.19 g (60 mmol) of fluorescent compound Io is obtained, with a yield of 88.2% and a purity of 99.53%.

[0293] 1 H NMR (400 MHz, CDCl3) δ 8.21 (dd, J = 2.1, 0.6 Hz, 2H), 8.17 – 8.10(m, 2H), 8.00 – 7.94 (m, 2H), 7.91 (dd, J = 6.6, 1.2 Hz, 2H), 7.71 (dd, J = 7.1,1.1 Hz, 2H), 7.65 – 7.53 (m, 6H), 7.53 – 7.40 (m, 4H), 3.79 (d, J = 4.4 Hz, 2H), 2.32~2.21 (m, 1H), 1.02 (d, J = 7.4 Hz, 6H).

[0294] Example 16

[0295] This embodiment provides a fluorescent compound (Ip, molecular weight 559.71) containing triazole and benzofuran fused with a benzene ring.

[0296]

[0297] Formula XX.

[0298] The synthesis method of the above-mentioned Ip comprises the following steps (see the reaction equation of Formula XX):

[0299] S1 is similar to Intermediate Synthesis Example 3, except that 2-isobutyl-4,7-dibromo-5,6-dimethoxybenzotriazole is replaced by an equal molar amount of 2-trimethylsilylethyl-4,7-dibromo-5,6-dimethoxybenzotriazole (which can be prepared by conventional methods, and its preparation method is not repeated here), and the remaining steps are the same as S1 of Intermediate Synthesis Example 3, and are not repeated here. 42.55 g (91 mmol) of the coupling intermediate (its specific structural formula is shown in Formula XX) is obtained, with a yield of 91% and a purity of 99.67%.

[0300] S2 is the same as S2 in Intermediate Synthesis Example 3, and will not be described in detail. A DMF solution containing a demethylation product intermediate (whose specific structural formula is shown in Formula XX) is obtained.

[0301] S3 is the same as S3 in Intermediate Synthesis Example 3, and is not described again. 30.36 g (76 mmol) of a condensed ring compound intermediate (its specific structural formula is shown in Formula XX) was obtained, and the combined yield of S2 to S3 was 83.5%, and the purity was 99.76%.

[0302] S4 is the same as S4 in Intermediate Synthesis Example 3, and is not described again. 35.67 g (64 mol) of a dibromo intermediate (its specific structural formula is shown in Formula XX) was obtained, with a yield of 84.2% and a purity of 99.64%.

[0303] S5, the above-mentioned dibromo intermediate, 16.37 g (130 mmol) of 1-methylpyrazole-5-boric acid, 300 mL of toluene and 250 mL of ethanol were added to a four-necked bottle, stirred evenly, and then potassium carbonate solution (prepared by 27.6 g of potassium carbonate and 200 mL of water) was added. After the nitrogen was evacuated, 161.78 mg (0.14 mmol) of tetrakistriphenylphosphine palladium was added in a nitrogen atmosphere, and the system was heated to reflux while stirring to react. After 8 hours, sampling was performed for monitoring. HPLC monitoring showed that the reaction was basically completely converted (remaining The reaction system was cooled to room temperature and allowed to stand for stratification. The aqueous layer was extracted with 300 mL of toluene. The toluene layers were combined and washed with water until neutral, dried over magnesium sulfate, and the desiccant was filtered out. The filtrate was purified by passing through a silica gel column (15 g silica gel). The column liquid was concentrated under reduced pressure to evaporate the solvent. 120 mL of ethanol was added, and the mixture was heated to reflux and then cooled to -10°C with stirring to precipitate a solid. The solid was filtered and dried to obtain 32.46 g (58 mmol) of the fluorescent compound Ip with a yield of 90.6% and a purity of 99.71%.

[0304] 1 H NMR (400 MHz, CDCl3) δ 8.25 (dd, J = 2.0, 0.7 Hz, 2H), 7.65 – 7.55(m, 4H), 7.47 (d, J = 3.2 Hz, 2H), 6.54 (d, J = 3.2 Hz, 2H), 3.87 (s, 6H), 3.79(t, J = 6.0 Hz, 2H), 1.14 (t, J = 6.0 Hz, 2H), 0.10 (s, 9H).

[0305] Performance Test 1

[0306] With reference to IEC61215, the fluorescent compounds in Examples 1 to 16 of the present invention and the comparative fluorescent compounds (respectively referred to as comparative examples 1 to 4, and the specific structural formulas are shown in I1 to I4 in Table 1) were tested for UV-visible light absorption spectra and fluorescence spectra. In the present invention, the absorption spectrum was tested using a UV-6100S ultraviolet-visible spectrophotometer (the solvent was a dichloromethane solution), and the results are shown in Table 1; the fluorescence spectrum was tested using a Hitachi F7100 fluorescence spectrophotometer, and the results are shown in Table 1. As can be seen from Table 1, the maximum absorption wavelength of the fluorescent compound provided by the present invention is 383 to 432 nm, the maximum emission wavelength is 569 to 628 nm, the molar absorption coefficient (ε) at the maximum absorption wavelength is 29200 to 31400 L / (mol·cm), and the light conversion efficiency is above 93%, and can even exceed 96%.

[0307] Table 1 Spectral properties of the fluorescent compounds in the examples and comparative fluorescent compounds

[0308]

[0309] Light conversion film embodiment 1

[0310] This embodiment provides a light-converting film, which is composed of the following raw materials in parts by weight: 100 parts of EVA, 0.05 parts of Ia, 0.5 parts of TBEC, 0.6 parts of TAIC and 0.4 parts of KH-560.

[0311] The preparation method of the above-mentioned light-converting film comprises the following steps: weighing various raw materials by weight, mixing them evenly, melt-extruding at 95° C., and casting to obtain a light-converting film with a thickness of 300 μm (thickness difference <5%).

[0312] Light conversion film embodiment 2

[0313] This embodiment provides a light-converting film, which is composed of the following raw materials in parts by weight: 100 parts of PVB, 0.05 parts of Ib, 0.5 parts of TAEC, 0.6 parts of TMPTA and 0.4 parts of KH-550.

[0314] The preparation method of the above-mentioned light-converting film comprises the following steps: weighing various raw materials by weight, mixing them evenly, melt-extruding at 80° C., and casting to obtain a light-converting film with a thickness of 300 μm (thickness difference <5%).

[0315] Light conversion film embodiment 3

[0316] This embodiment provides a light-converting film, which is composed of the following raw materials in parts by weight: 100 parts of PMMA, 0.05 parts of Ic, 0.5 parts of TBPIN, 0.6 parts of TAIC and 0.4 parts of KH-570.

[0317] The preparation method of the above-mentioned light-converting film comprises the following steps: weighing various raw materials by weight, mixing them evenly, melt-extruding at 105° C., and casting to obtain a light-converting film with a thickness of 300 μm (thickness difference <5%).

[0318] Light conversion film embodiment 4

[0319] This embodiment provides a light-converting film, which is composed of the following raw materials in parts by weight: 100 parts of POE, 0.005 parts of Id, 0.3 parts of BPDH, 0.3 parts of TMPTA, 0.1 parts of KH-792, 0.1 parts of UV-326 and 0.1 parts of antioxidant 1010.

[0320] The preparation method of the light-converting film is the same as that of the light-converting film embodiment 1, and will not be described in detail.

[0321] Light conversion film embodiment 5

[0322] This embodiment provides a light-converting film, which is composed of the following raw materials in parts by weight: 100 parts of EVA, 0.5 parts of Ie, 3 parts of TBPO, 3 parts of TAIC and 1 part of Z-6030.

[0323] The preparation method of the light-converting film is the same as that of the light-converting film embodiment 1, and will not be described in detail.

[0324] Light conversion film embodiment 6

[0325] This embodiment provides a light-converting film, which is composed of the following raw materials in parts by weight: 100 parts of EVA, 0.001 parts of If, 0.2 parts of DCP, 0.1 parts of TAIC, 0.1 parts of KH-560, 0.2 parts of UV-2908 and 0.2 parts of antioxidant 1076.

[0326] The preparation method of the light-converting film is the same as that of the light-converting film embodiment 1, and will not be described in detail.

[0327] Light conversion film examples 7 to 12

[0328] This embodiment provides a light-converting film, which is similar to the light-converting film embodiment 1, and the only difference is that the fluorescent compound Ia is replaced by Ig~Ij, Il and Im respectively. The preparation method is the same as the light-converting film embodiment 1 and will not be repeated.

[0329] Light conversion film comparison examples 1~4

[0330] This comparative example provides a light-conversion film, which is similar to the light-conversion film embodiment 1, except that the fluorescent compound Ia is replaced by I1~I4 respectively. The preparation method is the same as the light-conversion film embodiment 1 and will not be repeated here.

[0331] Light conversion film comparative example 5

[0332] This comparative example provides a light conversion film, which is similar to the light conversion film embodiment 1, and the only difference is that the fluorescent compound Ia is omitted. The preparation method thereof is the same as the light conversion film embodiment 1 and will not be repeated here.

[0333] Application Examples 1 to 12

[0334] This embodiment provides a photovoltaic module, the silicon wafer size of the heterojunction cell is 210 mm, and a 120-format module is made (using a conventional preparation method). The upper glass and the cell are encapsulated by the light-conversion films provided in Examples 1 to 12 of the light-conversion film.

[0335] Application Comparative Examples 1 to 5

[0336] The present comparative examples all provide a photovoltaic module, which is similar to the application examples 1 to 12, except that the light conversion films are replaced by the light conversion films provided in the light conversion film comparative examples 1 to 5, which will not be described in detail.

[0337] Performance Test 2

[0338] In order to evaluate the light conversion performance of the photovoltaic module, the photovoltaic modules provided by the application examples 1 to 12 of the present invention and the application comparison examples 1 to 5 were subjected to power test, 120 kWh UV aging test and module attenuation rate test with reference to IEC61215, and the results are shown in Table 2. As can be seen from Table 2, when the light conversion film is used as the packaging material of the HJT solar cell, when the dosage and production conditions are the same, after adding the light conversion film prepared by the present invention, the comprehensive efficiency of the photovoltaic module is greatly improved, and the stability is good.

[0339] Table 2 Comprehensive performance of photovoltaic modules of application examples and comparative examples

[0340]

[0341] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification, equivalent substitution or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A fluorescent compound containing triazole and benzofuran fused with a benzene ring, characterized in that: Its structural formula is shown in Formula 1: Formula 1; In the formula, X is hydrogen or fluorine; R 1 Taken from: C1~C18 straight chain alkyl, C3~C18 branched chain alkyl, C3~C18 cycloalkyl, C1~C5 straight chain silyl with trimethylsilyl as terminal group or C3~C5 branched chain silyl with trimethylsilyl as terminal group; R 2 Derived from: hydrogen, fluorine, trifluoromethyl, cyano, C1~C6 alkoxy, C2~C6 cycloalkoxy, aryl, heteroaryl, substituted aryl, substituted heteroaryl, phenylvinyl, phenylethynyl or N,N-disubstituted arylamine; R 3 Derived from: hydrogen, fluorine, trifluoromethyl, cyano, C1~C6 alkoxy, C2~C6 cycloalkoxy, aryl, heteroaryl, substituted aryl, substituted heteroaryl, phenylvinyl, phenylethynyl or N,N-disubstituted arylamine; R 2 , R 3 At least one of them is hydrogen or fluorine; in, The aryl group is phenyl, naphthyl, anthracenyl or phenanthrenyl; The heteroaryl group is a five-membered ring heteroaryl group, a six-membered ring heteroaryl group or a condensed ring heteroaryl group; the five-membered ring heteroaryl group is a thienyl group or a furyl group; the six-membered ring heteroaryl group is a pyridyl group or a pyrimidyl group; the condensed ring heteroaryl group is a carbazolyl group, a dibenzofuranyl group, a dibenzothienyl group, an indolyl group, a quinolyl group, a benzofuranyl group or a benzothienyl group; The substituted aryl group is a fluorophenyl group, a C1-C6 straight-chain or branched alkyl-substituted phenyl group, a benzene-substituted naphthyl group, a phenoxyphenyl group, or a C1-C5 alkoxy-substituted phenyl group; The substituted heteroaryl group is a fluorinated heteroaryl group, a phenyl substituted heteroaryl group, or a C1-C5 straight chain or branched alkyl substituted heteroaryl group; the substituted heteroaryl group is a substituted thienyl group, a substituted pyrazolyl group, a substituted pyridyl group, a substituted indolyl group, or a substituted carbazolyl group; The N,N-disubstituted arylamine group is N,N-bisphenylamine group, N,N-bisbiphenylamine group, N,N-phenylbiphenylamine group, N,N-phenylterphenylamine group, N,N-bisterphenylamine group or N,N-biphenylterphenylamine group.

2. The fluorescent compound containing triazole and benzofuran fused with a benzene ring as claimed in claim 1, characterized in that: The substituted aryl group is , , , , , , , , , , , , , or .

3. The fluorescent compound containing triazole and benzofuran fused with a benzene ring as claimed in claim 1, characterized in that: The structural formula of Formula 1 is selected from at least one of the structures shown in Formula 2-1 to Formula 2-44 and Formula 3-1 to Formula 3-39: ； 。 4. A light-converting film, characterized in that: The fluorescent compound comprising triazole and benzofuran fused with a benzene ring as described in any one of claims 1 to 3.

5. The light-converting film according to claim 4, characterized in that: The invention comprises the following raw material components in parts by weight: 100 parts of a polymer matrix, 0.0005-1 parts of a fluorescent compound containing triazole and benzofuran fused with a benzene ring, 0.2-3 parts of a crosslinking agent, 0.1-3 parts of a crosslinking auxiliary agent, 0.1-1 parts of a coupling agent, 0-0.2 parts of a light stabilizer and 0-0.2 parts of an antioxidant.

6. Use of the light conversion film according to claim 4 or 5 in photovoltaic modules.

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