A luminescent compound or a derivative thereof, an organic luminescent material with narrow-band emission, and a preparation method and application thereof

Abstract

The application discloses a light-emitting compound or a derivative thereof, which is based on an acridone as a main structure, a conjugate plane formed by the acridone and an intermediate benzene ring as a light-emitting center plane, and a hydrogen atom at at least one position of the intermediate benzene ring is replaced by a substituent group, a plane where the substituent group is located and the light-emitting center plane form an included angle alpha, and the alpha satisfies the following relationship: 0° < alpha < 180° or 180° < alpha < 360°. The application further provides an organic light-emitting material with narrow spectral band emission and a preparation method and application thereof. The light-emitting compound or the derivative thereof has the conjugate plane formed by the acridone and the intermediate benzene ring as the light-emitting center, and after a group changing the planarity is introduced, the problems of low color purity of an OLED device based on the acridone derivative and obvious spectral broadening under a high doping concentration are solved.

Description

Technical Field

[0001] This invention relates to the field of organic optoelectronic materials technology, specifically to a luminescent compound or its derivative, an organic luminescent material with narrow-band emission, its preparation method, and its application. Background Technology

[0002] Organic light-emitting diodes (OLEDs) offer significant advantages over traditional liquid crystal displays (LCDs), including self-illumination, low power consumption, high contrast, fast response, and flexible large-area fabrication, attracting widespread attention in both research and commercial applications. OLEDs consist of a stack of various functional thin films, typically including metal electrodes, hole transport layers, light-emitting layers, and electron transport layers. Among these, the light-emitting layer material has the greatest impact on the luminescence properties of OLED devices, being a key factor determining the device's emission peak position, luminous efficiency, color purity, and lifetime.

[0003] Because of vibrational coupling and excited-state structural relaxation in organic molecules, molecular emission spectra are typically broadened, leading to decreased color purity in devices. Currently, boron-nitrogen systems based on multiple resonances can achieve narrower fluorescence emission spectra, but device efficiency rolls off significantly, remaining far from commercial application standards. Organic light-emitting materials based on rigid conjugated structures often exhibit pronounced shoulder peaks in their emission spectra due to the presence of strong intramolecular stretching and shearing high-frequency vibrational modes. Professor Ma Yuguang's molecular structure design strategy of suppressing high-frequency vibrational coupling and promoting low-frequency vibrations can effectively reduce recombination energy and provides guidance for narrowing molecular emission spectra.

[0004] Acridinium is a linear tricyclic compound. Compared to anthracene and acridinium, acridinium exhibits stronger fluorescence emission characteristics and photostability, making it widely used in sensors and ion detection. Furthermore, acridinium molecules possess numerous active sites, making them easily modifiable, resulting in a rich variety and wide application of acridinium derivatives as organic electronic materials. However, despite the high luminescence quantum efficiency of many acridinium derivatives, their application in organic light-emitting diodes (OLEDs) is limited. This is because the broad fluorescence emission spectra, prominent shoulder peaks, and good planarity of many acridinium derivatives lead to severe aggregation quenching and significant spectral broadening, preventing the achievement of good color purity, external quantum efficiency, and other device performance characteristics in OLEDs. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, the purpose of this application is to provide a luminescent compound with narrow spectral emission, which takes the conjugated plane formed by acridinone and the intermediate benzene ring as the luminescent center, and solves the problems of low color purity and obvious spectral broadening at high doping concentration in OLED devices based on acridinone derivatives by introducing groups that change its planarity.

[0006] To solve the above problems, the technical solution adopted in this application is as follows:

[0007] This application provides a luminescent compound or derivative, which has an acridinone as the main structure and the conjugated plane formed by the acridinone and the intermediate benzene ring as the luminescent center plane. At least one hydrogen atom on the intermediate benzene ring is replaced by a substituent group. The plane containing the substituent group forms an angle α with the luminescent center plane. α satisfies the following relationship: 0° < α < 180° or 180° < α < 360°.

[0008] As a further preferred embodiment, the luminescent compound or derivative described in this application is a compound having the following structural formula (Ⅰ) or a derivative containing structural formula (Ⅰ):

[0009]

[0010] At least one of the planes containing the substituents R1 and R2 forms an angle α with the conjugate plane formed by the intermediate benzene ring at its location.

[0011] As a further preferred embodiment, in the luminescent compounds or derivatives described in the embodiments of this application, R1 and R2 are both groups containing aromatic ring structures, or groups containing heterocyclic structures, or groups containing both aromatic ring and heterocyclic structures.

[0012] As a further preferred embodiment, in the luminescent compound or derivative described in this application, R1 and R2 are the same or different substituent groups, selected from one of the following groups:

[0013]

[0014] In the above groups, "·" indicates the bonding position.

[0015] This application also provides an organic light-emitting material with narrow-band emission, which is based on acridinone as the main structure, with the conjugated plane formed by acridinone and the intermediate benzene ring as the light-emitting center plane. At least one hydrogen atom on the intermediate benzene ring is replaced by a substituent group, and the plane containing the substituent group forms an angle α with the light-emitting center plane. α satisfies the following relationship: 0°<α<180° or 180°<α<360°.

[0016] As a further preferred embodiment, the organic light-emitting material with narrow-band emission described in this application is a compound having the following structural formula (Ⅰ) or a derivative containing structural formula (Ⅰ):

[0017]

[0018] At least one of the planes containing the substituents R1 and R2 forms an angle α with the conjugate plane of the intermediate benzene ring at its location.

[0019] This application also provides a method for preparing a luminescent compound or its derivative, comprising the following steps:

[0020] Preparation of di-tert-butyl acridinone: 9(10H)-acridone was reacted with tert-chlorobutane to obtain a compound with the chemical structural formula (1);

[0021]

[0022] Preparation of compound 2Ac-Ph: The above compound having chemical structural formula (1) was reacted with 1,4-dibromobenzene to obtain the compound having chemical structural formula (2);

[0023]

[0024] Preparation of 2Ac-Ph-X by halogenation reaction: The above compound with chemical structure (2) is subjected to halogenation reaction to obtain a compound with chemical structure (3);

[0025]

[0026] Where X is Cl or Br;

[0027] Elimination reaction to prepare compound 2AcPh: The above compound with chemical structure (3) was subjected to an elimination reaction to obtain a compound with chemical structure (4);

[0028]

[0029] Preparation of compound 2AcPh-X by halogenation: The above compound (4) is reacted with a halogen to prepare a compound with chemical structural formula (5), wherein X is Cl or Br;

[0030]

[0031] Preparation of product: Substituting the X on the benzene ring by introducing a substituent group into the above compound (5) yields compound (Ⅰ).

[0032] As a further preferred embodiment, in the preparation method described in this application, compound (Ⅰ) is the product of the reaction of compound (5) with one or / and two of the following compounds:

[0033]

[0034] As a further preferred embodiment, in the preparation method described in this application, the step of preparing di-tert-butyl acridinone is to react the mixture of 9(10H)-acridone and anhydrous aluminum trichloride dissolved in dichloromethane under an inert gas protection environment with tert-butane chloride to form the product; wherein the molar ratio of 9(10H)-acridone, anhydrous aluminum trichloride and tert-butane chloride is 1:(2-4):(3-8).

[0035] As a further preferred embodiment, in the preparation method described in this application, the step of preparing compound 2Ac-Ph is carried out in an inert gas environment, using N,N-dimethylformamide as solvent, cuprous iodide as catalyst, and 2,2,6,6-tetramethyl-3,5-heptadecylone as catalyst ligand, in the presence of potassium carbonate, compound (1) reacts with 1,4-dibromobenzene; wherein, the molar ratio of compound (1), 1,4-dibromobenzene, cuprous iodide, 2,2,6,6-tetramethyl-3,5-heptadecylone, and potassium carbonate is 1:(0.4~0.6):(0.1~0.5):(0.2~1):(1~3).

[0036] As a further preferred embodiment, in the preparation method described in this application, in the step of preparing 2Ac-Ph-X by halogenation reaction, compound (2) is dissolved in dichloromethane and halogenation reaction occurs in the presence of potassium carbonate; wherein, the molar ratio of compound (2), halogen element and potassium carbonate is 1:(2~30):(2~6), and the reaction conditions refer to a light-protected environment at -5~5℃ and a reaction time of 24~48h.

[0037] As a further preferred embodiment, in the preparation method described in this application, in the step of eliminating reaction to prepare compound 2AcPh, N,N-dimethylacetamide is used as solvent, palladium acetate is used as catalyst, tricyclohexylphosphine tetrafluoroborate is used as catalyst ligand, and potassium carbonate is present in the presence of alkaline potassium carbonate, compound (3) undergoes self-cyclization reaction. The molar ratio of compound (3), palladium acetate, tricyclohexylphosphine tetrafluoroborate, and potassium carbonate is 1:(0.04~0.1):(0.08~0.2):(1~4), the reaction temperature is 130~160℃, and the reaction time is 12~48h.

[0038] As a further preferred embodiment, in the preparation method described in the present application, during the preparation of compound (5), compound (4) is dissolved in dichloromethane and reacted with halogen in the presence of potassium carbonate. The molar ratio of compound (4), halogen element, and potassium carbonate is 1:(2-30):(2-6). The reaction conditions are -5 to 5°C in a light-protected environment and the reaction time is 24 to 48 hours.

[0039] As a further preferred embodiment, in the preparation method described in this application, compound (6) is prepared by a catalytic reaction in the presence of potassium carbonate in an inert gas protected environment.

[0040] This application also provides the application of the luminescent compounds or derivatives of this application in the fabrication of organic light-emitting electroluminescent devices. These organic light-emitting electroluminescent devices include, but are not limited to, light-emitting diodes.

[0041] This invention also provides an organic electroluminescent device, including an anode, an organic light-emitting layer, and a cathode, wherein the light-emitting material used in the organic light-emitting layer is the light-emitting compound or its derivative described in this application.

[0042] As a further preferred embodiment, the thickness of the organic light-emitting layer described in this application is 10-40 nm, wherein the luminescent compound accounts for 0.5% to 50% of the mass of the organic light-emitting layer.

[0043] As a further preferred embodiment, a hole injection layer and / or a hole transport layer are disposed between the organic light-emitting layer and the anode, and an electron injection layer and / or an electron transport layer are disposed between the organic light-emitting layer and the cathode.

[0044] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0045] 1. The luminescent compound described in this application uses an acridinone as the main structure, with the conjugated plane formed by the acridinone and the intermediate benzene ring as the luminescent center. The plane containing the substituent group R has an angle with the plane containing the luminescent center. Compared with the rigid plane of existing acridinone compounds, the substituent group and the luminescent center in the luminescent compound described in this application will have a certain degree of distortion, which makes the luminescent compound have more low-frequency vibrational characteristics and a smaller molecular recombination energy. This can effectively narrow the emission spectrum, effectively reduce the aggregation fluorescence quenching of the luminescent center under high doping concentration, and suppress the broadening of the emission spectrum; thus, fluorescent materials with high luminous efficiency and narrow emission bands can be obtained.

[0046] 2. When the luminescent compound described in this application is applied to organic electroluminescent devices, the sky-blue organic electroluminescent device with high external quantum efficiency and high color purity can effectively improve the luminous efficiency and narrow emission band characteristics of organic electroluminescent devices.

[0047] 3. The preparation methods and synthesis techniques described in this application are all relatively mature and convenient, which is conducive to large-scale industrial production.

[0048] The present invention will be further described in detail below with reference to specific embodiments. Attached Figure Description

[0049] Figure 1The fluorescence emission spectrum of product M1 in toluene solution (10⁻⁵ mol / L) is shown.

[0050] Figure 2 The electroluminescence spectrum of product M1 in an OLED device with 2,6-DCzPPy as the main material;

[0051] Figure 3 The curve of external quantum efficiency as a function of brightness for product M1 in an OLED device with 2,6-DCzPPy as the main material;

[0052] Figure 4 The current efficiency-voltage-brightness curves of product M1 in an OLED device using 2,6-DCzPPy as the main material are shown. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0054] The term "comprising" and other equivalent descriptive terms used in the specification and claims of this application are intended to cover a non-exclusive inclusion, which includes both the contents explicitly described in the specification and claims and steps or units that are not described in the specification and claims but are inherent in the product, method or structure.

[0055] This application provides a luminescent compound or derivative with an acridinone as the main structure and the conjugated plane formed by the acridinone and the intermediate benzene ring as the luminescent center plane. At least one hydrogen atom on the intermediate benzene ring is replaced by a substituent group. The plane containing the substituent group forms an angle α with the luminescent center plane, where α satisfies the following relationship: 0° < α < 180° or 180° < α < 360°. In this embodiment, because the plane containing the substituent group and the luminescent center plane are not on the same plane, the presence of the angle causes a certain degree of distortion between the two planes, altering the planar structure of the acridinone compound. The acridinone derivative material exhibits a narrower fluorescence emission spectrum, and fluorescence quenching and emission spectrum broadening in the aggregated state are effectively suppressed. The resulting luminescent compound has more low-frequency vibrational components in its vibrational modes, thus reducing molecular recombination energy and enabling narrow-band emission.

[0056] In specific embodiments of this application, the luminescent compound or derivative is a compound having the following structural formula (Ⅰ) or a derivative containing structural formula (Ⅰ):

[0057]

[0058] At least one plane containing the substituents R1 and R2 forms an angle α with the conjugate plane formed by the intermediate benzene ring at its location. In some embodiments, in the luminescent compound or derivative described in this application, R1 and R2 are groups containing aromatic ring structures, or groups containing heterocyclic structures, or groups containing both aromatic ring and heterocyclic structures. In some embodiments, R1 and R2 are the same or different substituents; preferably, R1 and R2 are the same substituent. The substituents in this application are selected from, but are not limited to, one of the following groups:

[0059]

[0060] In the above groups, "·" indicates the bonding position. These groups contain aromatic rings, have significant steric hindrance, and can rotate or twist after being attached to the host molecule as substituents.

[0061] This application also provides an organic light-emitting material with narrow-band emission, which is based on an acridinone as the main structure, with the conjugated plane formed by the acridinone and the intermediate benzene ring as the luminescent center plane. At least one hydrogen atom on the intermediate benzene ring is replaced by a substituent group, and the plane containing the substituent group forms an angle α with the luminescent center plane, where α satisfies the following relationship: 0° < α < 180° or 180° < α < 360°. Further, the organic light-emitting material with narrow-band emission is a compound having the following structural formula (Ⅰ) or a derivative containing structural formula (Ⅰ):

[0062]

[0063] At least one of the planes containing the substituents R1 and R2 forms an angle α with the conjugate plane of the intermediate benzene ring at its location.

[0064] This application also provides a method for preparing a luminescent compound or its derivative, comprising the following steps:

[0065] Preparation of di-tert-butyl acridinone: The mixture of 9(10H)-acridone and anhydrous aluminum trichloride dissolved in dichloromethane under an inert gas atmosphere was reacted with tert-butane chloroform to obtain a compound with chemical structural formula (1); wherein the molar ratio of 9(10H)-acridone, anhydrous aluminum trichloride and tert-butane chloroform is 1:(2~4):(3~8);

[0066]

[0067] Preparation of compound 2Ac-Ph: In an inert gas environment, using N,N-dimethylformamide as solvent, cuprous iodide as catalyst, and 2,2,6,6-tetramethyl-3,5-heptadecane as catalyst ligand, in the presence of potassium carbonate, compound (1) reacts with 1,4-dibromobenzene to obtain a compound with chemical structure (2); wherein, the molar ratio of compound (1), 1,4-dibromobenzene, cuprous iodide, 2,2,6,6-tetramethyl-3,5-heptadecane, and potassium carbonate is 1:(0.4~0.6):(0.1~0.5):(0.2~1):(1~3);

[0068]

[0069] Preparation of 2Ac-Ph-X by halogenation reaction: Compound (2) was dissolved in dichloromethane and halogenated in the presence of potassium carbonate to obtain a compound with chemical structure (3); wherein the molar ratio of compound (2), halogen element and potassium carbonate was 1:(2~30):(2~6), and the reaction conditions were -5~5℃ in the dark environment and the reaction time was 24~48h;

[0070]

[0071] Where X is Cl or Br;

[0072] Elimination reaction to prepare compound 2AcPh: Using N,N-dimethylacetamide as solvent, in an inert gas protected environment, using palladium acetate as catalyst, tricyclohexylphosphine tetrafluoroborate as catalyst ligand, and in the presence of basic potassium carbonate, compound (3) undergoes self-cyclization reaction to obtain a compound with chemical structure (4); the molar ratio of compound (3), palladium acetate, tricyclohexylphosphine tetrafluoroborate, and potassium carbonate is 1:(0.04~0.1):(0.08~0.2):(1~4), the reaction temperature is 130~160℃, and the reaction time is 12~48h;

[0073]

[0074] Preparation of compound 2AcPh-X by halogenation reaction: Compound (4) was dissolved in dichloromethane and reacted with halogen in the presence of potassium carbonate to prepare a compound with chemical structural formula (5). The molar ratio of compound (4), halogen element and potassium carbonate was 1:(2~30):(2~6). The reaction conditions were -5~5℃ in the dark and the reaction time was 24~48h. X was Cl or Br.

[0075]

[0076] Preparation of the product: In an inert gas-protected environment, a catalyst reaction was carried out in the presence of potassium carbonate to introduce a substituent group to replace X on the benzene ring in the above compound (5) to obtain compound (Ⅰ).

[0077] In the preparation method described in the embodiments of this application, compound (Ⅰ) is the product of the reaction of compound (5) with the following compounds, wherein the R1 and R2 groups in compound (Ⅰ) are derived from the following compounds; in some embodiments, the R1 and R2 groups are the same group, and compound (5) reacts with one of the following compounds, wherein the species X is replaced by the same group; in other embodiments, compound (5) may also undergo a substitution reaction with any two of the following compounds, wherein R1 and R2 are different groups;

[0078]

[0079] This application also provides the application of the luminescent compounds or derivatives of this application in the fabrication of organic light-emitting electroluminescent devices. In some embodiments, the organic light-emitting device includes an anode, an organic light-emitting layer, and a cathode, wherein the luminescent material used in the organic light-emitting layer is the luminescent compound or its derivative described in this application. The organic light-emitting electroluminescent device includes, but is not limited to, a light-emitting diode. Further, a hole injection layer and / or a hole transport layer are disposed between the organic light-emitting layer and the anode, and an electron injection layer and / or an electron transport layer are disposed between the organic light-emitting layer and the cathode.

[0080] In some embodiments, the thickness of the organic light-emitting layer described in this application is 10-40 nm, and the host material in the light-emitting layer is 2,6-DczPPy. If the proportion of the luminescent compound in the light-emitting layer is too low, it may cause insufficient energy transfer between the host and guest molecules and a decrease in the external quantum efficiency of the device; if the proportion of the luminescent compound in the light-emitting layer is too high, it may cause significant spectral broadening of the light-emitting layer, severe fluorescence quenching, and may also cause an imbalance in carrier injection between the electron / hole transport layer and the light-emitting layer in the OLED device. Therefore, in order to ensure that the light-emitting layer has good luminescence performance and device performance, i.e., a narrow half-width at half-maximum, high luminescence quantum efficiency, and good carrier transport performance, in some embodiments of this application, the mass proportion of the luminescent compound in the organic light-emitting layer is 0.5% to 50%.

[0081] In some embodiments, the organic electroluminescent device structure can take many forms. For example, a first structure may include ITO, PEDOT:PSS (40 nm thick), an organic light-emitting layer (30 nm thick), a LiF layer (1 nm thick), and an Al layer (100 nm thick). A second structure may include ITO, PEDOT:PSS (40 nm thick), a hole transport layer (30–50 nm thick), an organic light-emitting layer (30 nm thick), a LiF layer (1 nm thick), and an Al layer (100 nm thick). A third structure may include ITO, PEDOT:PSS (40 nm thick), an organic light-emitting layer (30 nm thick), an electron transport layer (30–50 nm thick), a LiF layer (1 nm thick), and an Al layer (100 nm thick). The fourth structure includes ITO, PEDOT:PSS (40nm thick), a hole transport layer (30-50nm thick), an organic light-emitting layer (30nm thick), an electron transport layer (30-50nm thick), a LiF layer (1nm thick), and an Al layer (100nm thick). The fifth structure includes ITO, HAT-CN (5nm thick), a hole transport layer (30-50nm thick), an organic light-emitting layer (30nm thick), an electron transport layer (30-50nm thick), a LiF layer (1nm thick), and an Al layer (100nm thick).

[0082] Furthermore, in the aforementioned organic electroluminescent device structure, the hole transport layer functions as a hole transport layer, employing an aromatic compound containing electron-rich groups. Specifically, a wealth of hole transport materials can be selected, but are not limited to, NPB (N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine) and TCTA (4,4',4'-tris(carbazole-9-yl)triphenylamine). The electron transport layer functions as an electron transport layer, employing an aromatic compound containing electron-discarding groups. Specifically, a selectable electron transport material is TmPyPb (3,3'-[5'-[3-(3-pyridyl)phenyl][1,1':3',1”-terphenyl]-3,3”-diyl]dipyridine).

[0083] The following are specific embodiments of this application. Unless otherwise specified in this application, the instruments and reagents used in the following embodiments can be obtained commercially.

[0084] Example 1

[0085] The sky-blue narrow-band luminescent compound M1 in this embodiment has the following structural formula:

[0086]

[0087] The synthetic route for compound M1 is as follows:

[0088]

[0089] (1) Preparation of compound 2,7-di-tert-butylacridone (Ac):

[0090] Under argon protection, 9(10H)-acridone (10.00 g, 51.2 mmol, 1 equivalent) and anhydrous aluminum trichloride (13.65 g, 102.4 mmol, 2 equivalents) were dissolved in 240 mL of ultra-dry dichloromethane. Tert-butane chloride (37.92 g, 409.6 mmol, 8 equivalents) was added to the mixture, and the solution was stirred at 0 °C for 24 h. The reaction was quenched with deionized water, and the mixture was extracted three times with dichloromethane. The extracted organic layer was washed three times with deionized water, and anhydrous magnesium sulfate was added to remove water before filtration. The crude product obtained after removing the organic solvent by rotary evaporation under reduced pressure was purified by column chromatography using a mixture of ethyl acetate and petroleum ether as the eluent. A total of 10.80 g of the pale yellow solid product Ac was obtained, with a yield of 69%. 1 HNMR, 13 The obtained product was characterized by CNMR, MALDI-TOF-MS and elemental analysis, and the results showed that the obtained compound was indeed the target product.

[0091] (2) Preparation of compound 2Ac-Ph

[0092] Under argon protection, Ac (1535 mg, 5.0 mmol, 1 equivalent), 1,4-dibromobenzene (708 mg, 3.0 mmol, 0.6 equivalent), cuprous iodide (191 mg, 1.0 mmol, 0.2 equivalent), 2,2,6,6-tetramethyl-3,5-heptadecylone (369 mg, 2.0 mmol, 0.4 equivalent), and potassium carbonate (1037 mg, 7.5 mmol, 1.5 equivalent) were dissolved in 20 mL of N,N-dimethylformamide (DMF). The reaction mixture was stirred and refluxed at 155 °C for 24 h. After the reaction was complete, DMF was removed by vacuum distillation. Deionized water was added to the solid mixture, followed by extraction three times with dichloromethane. The resulting organic layer was washed three times with deionized water. Anhydrous magnesium sulfate was added to the organic layer to remove water, and the mixture was filtered. The organic solvent was removed by rotary evaporation under reduced pressure. The crude product was purified by column chromatography using a mixture of dichloromethane and petroleum ether as the eluent. The final purified solid product was pale yellow, totaling 1630 mg, with a yield of 95%. [Usage] 1 HNMR, 13 The obtained product was characterized by CNMR, MALDI-TOF-MS and elemental analysis, and the results showed that the obtained compound was indeed the target product. (3) Preparation of compound 2Ac-Ph-Br

[0093] Compound 2Ac-Ph (2.45 g, 3.56 mmol, 1 equivalent) was dissolved in 300 mL of dichloromethane. Liquid bromine (6.38 g, 40 mmol, 10 equivalents) was added dropwise to the reaction system. The reaction mixture was stirred at room temperature for 2 h in a sealed, light-protected environment, followed by the addition of potassium carbonate (1.11 g, 8 mmol, 2 equivalents). The mixture was then stirred at room temperature for 46 h in a sealed, light-protected environment. After the reaction was complete, an excess of saturated sodium bisulfite solution was added to remove unreacted liquid bromine, and the mixture was extracted three times with dichloromethane. The organic layer was washed three times with deionized water and then dehydrated with anhydrous magnesium sulfate. The dehydrated organic layer was then subjected to rotary evaporation under reduced pressure to remove the organic solvent. The resulting crude solid product was purified by column chromatography using a mixture of dichloromethane and petroleum ether as the eluent. The final purified product, 2.74 g of 2Ac-Ph-Br, was obtained as a pale yellow solid with a yield of 91%. 1 HNMR, 13 The obtained product was characterized by CNMR, MALDI-TOF-MS and elemental analysis, and the results showed that the obtained compound was indeed the target product.

[0094] (4) Preparation of compound 2AcPh

[0095] Under argon protection, 2Ac-Ph-Br (2700 mg, 3.19 mmol, 1 equivalent), palladium acetate (32 mg, 0.19 mmol, 0.06 equivalent), tricyclohexylphosphine tetrafluoroborate (140 mg, 0.38 mmol, 0.12 equivalent), and potassium carbonate (882 mg, 6.38 mmol, 2 equivalent) were dissolved in 20 mL of N,N-dimethylacetamide (DMA). The reaction mixture was stirred and refluxed at 130 °C for 24 hours. After the reaction was complete, DMA was removed by vacuum distillation. The product was extracted with dichloromethane and washed three times with deionized water. The organic layer was dried over anhydrous magnesium sulfate. The organic solvent was removed by rotary evaporation under reduced pressure. The resulting crude solid product was purified by column chromatography using a mixture of ethyl acetate and petroleum ether as the eluent. The purified solid product was recrystallized from a mixture of dichloromethane and methanol and filtered to obtain the purified final product 2AcPh. Compound 2AcPh is a yellow solid, with a total yield of 1426 mg and a yield of 65%. Use 1 HNMR, 13 The obtained product was characterized by CNMR, MALDI-TOF-MS and elemental analysis, and the results showed that the obtained compound was indeed the target product.

[0096] (5) Preparation of compound 2AcPh-Br

[0097] Compound 2AcPh (810 mg, 1.18 mmol, 1 equivalent) was dissolved in 600 mL of dichloromethane. Liquid bromine (3772 mg, 23.6 mmol, 20 equivalents) was added dropwise to the reaction system. The reaction mixture was stirred at room temperature for 2 h in a sealed, light-protected environment, followed by the addition of potassium carbonate (326 mg, 2.36 mmol, 2 equivalents). The mixture was then stirred at room temperature for 46 h in a sealed, light-protected environment. After the reaction was complete, an excess of saturated sodium bisulfite solution was added to remove unreacted liquid bromine, and the mixture was extracted three times with dichloromethane. The organic layer was washed three times with deionized water and then dehydrated with anhydrous magnesium sulfate. The dehydrated organic layer was then subjected to rotary evaporation under reduced pressure to remove the organic solvent. The resulting crude solid product was purified by column chromatography using a mixture of dichloromethane and petroleum ether as the eluent. The final purified product, 2AcPh-Br, was obtained in a total of 840 mg, as a pale yellow solid, with a yield of 84%. 1 HNMR, 13 The obtained product was characterized by CNMR, MALDI-TOF-MS and elemental analysis, and the results showed that the obtained compound was indeed the target product.

[0098] (6) Preparation of compound M1

[0099] Under argon protection, compounds 2AcPh-Br (506 mg, 0.6 mmol, 1 equivalent), pinacol 4-fluorophenylboronic acid (294 mg, 1.32 mmol, 2.2 equivalent), tetrakis(triphenylphosphine)palladium (69 mg, 0.06 mmol, 0.1 equivalent), and potassium carbonate (249 mg, 1.8 mmol, 3.0 equivalent) were dissolved in 20 mL of a mixed solvent of tetrahydrofuran and water (tetrahydrofuran:water = 3:1, volume ratio). The reaction mixture was stirred and refluxed at 70 °C for 24 h, after which heating was stopped. After cooling to room temperature, the mixture was extracted three times with dichloromethane. The resulting organic layer was washed three times with deionized water and dried over anhydrous magnesium sulfate. The organic solvent was removed by vacuum distillation, and the resulting crude solid was purified by column chromatography using a mixed solvent of ethyl acetate and petroleum ether as the eluent. The solid product obtained by column chromatography was recrystallized in a mixed solution of dichloromethane and methanol, and filtered to obtain the purified final product M1.

[0100] Compound M1 was a yellowish-green solid, with a total yield of 320 mg and a yield of 61%. [Usage] 1 HNMR, 13 The obtained product was characterized by CNMR, MALDI-TOF-MS, and elemental analysis, and the results showed that the obtained compound was indeed the target product. Compound M1 showed a high concentration of 10 NMR ions. -5 The fluorescence emission spectrum measured in a mol / L toluene solution showed that the emission peak of compound M1 was at 479 nm with a full width at half maximum (FWHM) of 20 nm.

[0101] Example 2

[0102] This embodiment provides a sky-blue narrow-band luminescent compound M2, with the following structural formula:

[0103]

[0104] The synthetic route for compound M2 is as follows:

[0105]

[0106] In the synthetic route of compound M2, the steps from the synthesis of Ac to the synthesis of 2AcPh-Br are the same as those in the implementation method in Example 1.

[0107] Preparation of compound M2:

[0108] Following steps (1)-(5) of Example 1 above, 2AcPh-Br was obtained. Then, under argon protection, 2AcPh-Br (300 mg, 0.36 mmol, 1 equivalent), carbazole (132 mg, 0.79 mmol, 2.2 equivalent), cuprous iodide (27 mg, 0.14 mmol, 0.4 equivalent), 2,2,6,6-tetramethyl-3,5-heptadecylone (53 mg, 0.29 mmol, 0.8 equivalent), and potassium carbonate (149 mg, 1.08 mmol, 3 equivalent) were dissolved in 12 mL of N,N-dimethylformamide (DMF). The reaction mixture was stirred and refluxed at 155 °C for 24 h. After the reaction was complete, DMF was removed by vacuum distillation. Deionized water was added to the solid mixture, followed by extraction three times with dichloromethane. The resulting organic layer was washed three times with deionized water. Anhydrous magnesium sulfate was added to the organic layer to remove water, and then the mixture was filtered. The organic solvent was removed by rotary evaporation under reduced pressure. The crude product was then purified by column chromatography using a mixture of dichloromethane and petroleum ether as the eluent. The solid product obtained by column chromatography was recrystallized in a mixed solution of dichloromethane and methanol, and filtered to obtain the purified final product M2.

[0109] The final purified solid product M6 was yellow-green, totaling 55 mg, with a yield of 15%. [Usage] 1 HNMR, 13 The obtained product was characterized by CNMR, MALDI-TOF-MS and elemental analysis, and the results showed that the obtained compound was indeed the target product.

[0110] Application Example 1

[0111] An organic electroluminescent device is provided: Indium tin oxide (ITO) conductive glass is ultrasonically cleaned for 30 minutes each with acetone, isopropanol, deionized water, ITO cleaning solution, acetone, deionized water, and isopropanol in sequence, and then dried and treated with plasma for 15 minutes. Using ITO as the anode, in a vacuum evaporation apparatus, a 5 nm thick layer of 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazabenzophenanthrene (HAT-CN) was sequentially deposited on the ITO surface as a hole injection layer, a 50 nm thick layer of N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine (NPB) was deposited as a hole transport layer, a 5 nm thick layer of 4,4',4”-tris(carbazole-9-yl)triphenylamine (TCTA) was deposited as an exciton blocking layer, and a 20 nm thick layer of 2,6-bis((9H-carbazole-9-yl)-3,1-phenylene)pyridine (2,6-D) was deposited. A uniformly mixed film of CzPPy (97% by mass) and compound M1 (3% by mass) serves as the light-emitting layer. A 40 nm thick 1,3,5-tris[(3-pyridyl)-3-phenyl]benzene (TmPyPb) serves as the electron transport layer. A 1 nm thick lithium fluoride (LiF) serves as the electron injection layer. A 100 nm thick aluminum (Al) serves as the electron cathode. The device structure is: ITO / HAT-CN (5 nm) / NPB (50 nm) / TCTA (5 nm) / M2:2,6-DCzPPy3% (20 nm) / TmPyPb (40 nm) / LiF (1 nm) / Al (100 nm).

[0112] Electroluminescence spectra were measured using a PR650 fluorescence spectrophotometer, and the current density-voltage-luminance curves were simultaneously determined using a computer-controlled light source (Keithley 2400) equipped with an LS-110 light intensity meter. Assuming the emitted light follows a Lambertian distribution, the external quantum efficiency was calculated based on the current density, luminance, and electroluminescence spectra. Full width at half maximum (FWHM) and CIE coordinates were obtained from the electroluminescence spectra.

[0113] The performance of the organic electroluminescent devices prepared by the above method is described in [reference needed]. Figure 1-4 See Table 1.

[0114] Table 1: Organic electroluminescence performance of doped devices based on compound M1

[0115]

[0116] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

[0117] The embodiments described in this application are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A luminescent compound, characterized in that, It has an acridinone as the main structure, with the conjugated plane formed by the acridinone and the intermediate benzene ring as the luminescent center plane. At least one hydrogen atom on the intermediate benzene ring is replaced by a substituent group. The plane containing the substituent group forms an angle α with the luminescent center plane, and α satisfies the following relationship: 0° < α < 180° or 180° < α < 360°. It has the following structural formula (Ⅰ). Wherein, at least one plane containing substituents R1 and R2 forms an angle α with the conjugate plane formed by the intermediate benzene ring at its position; wherein R1 and R2 are the same or different substituents, selected from one of the following groups: In the above groups, "·" indicates the bonding position.

2. An organic light-emitting material with narrow spectral band emission, characterized in that, It has an acridinone as the main structure, with the conjugated plane formed by the acridinone and the intermediate benzene ring as the luminescent center plane. At least one hydrogen atom on the intermediate benzene ring is replaced by a substituent group, and the plane containing the substituent group forms an angle α with the luminescent center plane, where α satisfies the following relationship: 0° < α < 180° or 180° < α < 360°; it has the following structural formula (Ⅰ): The plane containing substituents R1 and R2 forms an angle α with the conjugate plane of the intermediate benzene ring at its location; R1 and R2 are the same or different substituents, selected from one of the following groups: In the above groups, "·" indicates the bonding position.

3. A method for preparing the luminescent compound as described in claim 1, characterized in that, Includes the following steps: Preparation of di-tert-butyl acridinone: 9(10H)-acridone was reacted with tert-chlorobutane to obtain a compound with the chemical structural formula (1); Preparation of compound 2Ac-Ph: The above compound having chemical structural formula (1) was reacted with 1,4-dibromobenzene to obtain the compound having chemical structural formula (2); Preparation of 2Ac-Ph-X by halogenation reaction: The above compound with chemical structure (2) is subjected to halogenation reaction to obtain a compound with chemical structure (3); Where X is Cl or Br; Elimination reaction to prepare compound 2AcPh: The above compound with chemical structure (3) was subjected to an elimination reaction to obtain a compound with chemical structure (4); Preparation of compound 2AcPh-X by halogenation: The above compound (4) is reacted with a halogen to prepare a compound with chemical structural formula (5), wherein X is Cl or Br; Preparation of product: Substituting the X on the benzene ring by introducing a substituent group into the above compound (5) yields compound (Ⅰ).

4. The preparation method according to claim 3, characterized in that, Compound (Ⅰ) is the product of the reaction of compound (5) with one or / and two of the following compounds:

5. The preparation method according to claim 3, characterized in that, In the preparation of di-tert-butyl acridinone, the product is obtained by reacting a mixture of 9(10H)-acridone and anhydrous aluminum trichloride dissolved in dichloromethane under an inert gas atmosphere with tert-butane chloride; wherein the molar ratio of 9(10H)-acridone, anhydrous aluminum trichloride, and tert-butane chloride is 1:(2-4):(3-8); In the preparation of compound 2Ac-Ph, N,N-dimethylformamide was used as a solvent in an inert gas environment, with cuprous iodide as a catalyst and 2,2,6,6-tetramethyl-3,5-heptadecane as a catalyst ligand, and in the presence of potassium carbonate, compound (1) reacted with 1,4-dibromobenzene; wherein the molar ratio of compound (1), 1,4-dibromobenzene, cuprous iodide, 2,2,6,6-tetramethyl-3,5-heptadecane, and potassium carbonate was 1:(0.4~0.6):(0.1~0.5):(0.2~1):(1~3); In the step of preparing 2Ac-Ph-X by halogenation reaction, compound (2) is dissolved in dichloromethane and halogenation reaction occurs in the presence of potassium carbonate; wherein, the molar ratio of compound (2), halogen element and potassium carbonate is 1:(2~30):(2~6), and the reaction conditions refer to the reaction in a light-protected environment at -5~5℃ for 24~48h. In the step of preparing compound 2AcPh by elimination reaction, N,N-dimethylacetamide is used as solvent, palladium acetate is used as catalyst, tricyclohexylphosphine tetrafluoroborate is used as catalyst ligand, and potassium carbonate is used in the presence of alkaline potassium carbonate. Compound (3) undergoes self-cyclization reaction. The molar ratio of compound (3), palladium acetate, tricyclohexylphosphine tetrafluoroborate and potassium carbonate is 1:(0.04~0.1):(0.08~0.2):(1~4). The reaction temperature is 130~160℃ and the reaction time is 12~48h. In the preparation of compound (5), compound (4) was dissolved in dichloromethane and reacted with halogen in the presence of potassium carbonate. The molar ratio of compound (4), halogen element and potassium carbonate was 1:(2~30):(2~6). The reaction conditions were -5~5℃ in the dark and the reaction time was 24~48h. Compound (6) was prepared by a catalytic reaction in the presence of potassium carbonate in an inert gas-protected environment.

6. The use of the luminescent compound as described in claim 1 in the preparation of organic light-emitting electroluminescent devices.

7. An organic electroluminescent device, comprising an anode, an organic light-emitting layer, and a cathode, characterized in that, The luminescent material used in the organic light-emitting layer is the luminescent compound described in claim 1.

8. The organic electroluminescent device according to claim 7, characterized in that, The thickness of the organic light-emitting layer is 10-40 nm, and the mass percentage of the light-emitting compound in the organic light-emitting layer is 0.5% to 50%.

9. The organic electroluminescent device according to claim 7, characterized in that, A hole injection layer and / or a hole transport layer are disposed between the organic light-emitting layer and the anode, and an electron injection layer and / or an electron transport layer are disposed between the organic light-emitting layer and the cathode.

Images