Polycyclic compounds and organic electroluminescent devices comprising the same

Abstract

This invention discloses a polycyclic compound and an organic electroluminescent device containing the same. The invention introduces a bridged ring structure to reduce the electron-donating ability of nitrogen atoms, and further weakens this ability through a bridged ring and benzene ring structure, avoiding a redshift in the material's emission. Compared to the benzene ring, the twisted structure of the bridged ring weakens the intermolecular interactions caused by this planar configuration, which is more conducive to the dispersion of dopants in the host material, effectively avoiding fluorescence quenching and improving luminescence efficiency. Simultaneously, the use of a double boron framework allows the material to maintain a narrow half-width at half-maximum (WHM), resulting in devices fabricated using the compound of this invention exhibiting excellent performance in terms of efficiency and lifetime.

Description

Technical Field

[0001] This invention belongs to the field of OLED technology, specifically including a polycyclic compound and an organic electroluminescent device containing the same. Background Technology

[0002] Compared with other flat panel display elements such as liquid crystal displays (LCDs), plasma display panels (PDPs), and field emission displays (FEDs), organic light-emitting diodes (OLEDs) have a simple structure, various advantages in manufacturing processes, high brightness and excellent viewing angle characteristics, fast response speed, and are being actively developed and commercialized due to their low driving voltage. This makes them suitable for use as light sources in flat panel displays such as wall-mounted TVs, backlighting of displays, lighting, billboards, etc.

[0003] The materials used in the organic layer of organic electroluminescent devices are mostly pure organic materials or complex compounds formed by organic materials and metals. Depending on their application, they can be classified as hole injection materials, hole transport materials, luminescent materials, electron transport materials, and electron injection materials. Preferably, the luminescent layer material is a material that is stable in both oxidative and reduced states, and preferably a material with high luminous efficiency in converting excitons into light. More specifically, the luminescent layer consists of a host material and a dopant material. The dopant needs to have high quantum efficiency, and the host material preferably has a larger bandgap than the dopant material to facilitate energy transfer to the dopant. Displays used in televisions, mobile devices, etc., achieve full color using red, green, and blue colors, and the luminescent layers are respectively composed of a red host / dopant, a green host / dopant, and a blue host / dopant.

[0004] Commonly used blue fluorescent materials include coumarin and anthracene. The full width at half maximum (FWHM) of these materials is usually around 40 nm. These materials introduce a large rigid molecular framework to restrict nonradiative transitions such as vibration and rotation in the solid state. However, the rigid planar structure is prone to intermolecular aggregation, which makes it easy for fluorescence quenching to occur, thereby reducing efficiency.

[0005] In recent years, novel TADF luminescent materials induced by multiple-resonance (MR) have attracted more attention due to their rigid molecular framework and fine frontier orbital distribution, enabling high EQE and narrow HWHM. These materials are often referred to as boron-nitrogen structures. They utilize heteroatoms to break the conjugation between rigid aromatic rings, and use the opposite resonance effect of electron-rich nitrogen atoms and electron-deficient boron atoms to separate HOMO and LUMO within a strongly π-conjugated framework. This allows the distribution of transition electrons to be localized on individual atoms, reducing nuclear geometry changes and narrowing the spectrum. To further optimize the boron-nitrogen structure, electron-donating groups, electron-withdrawing groups, and heteroatoms are often introduced into the boron / nitrogen resonance framework to adjust luminescence efficiency or color. However, these measures inevitably increase intramolecular charge transfer processes, leading to a broadened HWHM, redshift in emission, and decreased color purity.

[0006] Therefore, it is still necessary to develop a material with excellent device performance to solve the above problems. Summary of the Invention

[0007] In view of the above-mentioned problems in the prior art, the present invention provides a polycyclic compound and an organic electroluminescent device containing the same.

[0008] To achieve the above objectives, the technical solution adopted by the present invention includes:

[0009] In a first aspect, the present invention provides a polycyclic compound having the general structural formula shown in Formula I:

[0010]

[0011] In this context, ring A indicates a carbon number of C4 to C5. 30 Substituted or unsubstituted bridged alkyl groups with a carbon number of C4 to C5 30 One of the substituted or unsubstituted bridged cyclic olefins; ring B indicates a carbon number of C6 to C6. 60 The substituted or unsubstituted aryl group has a carbon number of C5 to C6. 60 Substituted or unsubstituted heteroaryl groups with a carbon number of C6 to C5 60 Substituted or unsubstituted fused-ring aryl groups with a carbon number of C5 to C6. 60 One of the substituted or unsubstituted heterocyclic aryl groups;

[0012] m, n, and p each independently represent 1, 2, or 3; when m, n, and p are 2 or 3, R1, R2, and R4 can be the same or different.

[0013] R1 and R2 independently represent hydrogen, deuterium, halogen, and carbon atoms with numbers C1 to C2. 30 The substituted or unsubstituted alkyl group has a carbon number of C1 to C2.30 The substituted or unsubstituted alkoxy group has a carbon number of C2 to C3. 30 The substituted or unsubstituted alkenyl group has a carbon number of C3 to C4. 30 Substituted or unsubstituted cycloalkyl groups with a carbon number of C6 to C5 60 The substituted or unsubstituted aryl group has a carbon number of C6 to C6. 60 Substituted or unsubstituted heteroaryl groups with a carbon number of C6 to C5 60 Substituted or unsubstituted fused-ring aryl groups with a carbon number of C5 to C6. 60 One of the substituted or unsubstituted heterocyclic aryl group, substituted or unsubstituted amino group, and substituted or unsubstituted ether group; the two or more R1s can be connected to each other to form a ring, and the two or more R2s can be connected to each other to form a ring;

[0014] R3 indicates hydrogen, deuterium, halogen, or carbon atoms with a carbon number of C1 to C2. 30 The substituted or unsubstituted alkyl group has a carbon number of C2 to C3. 30 The substituted or unsubstituted alkenyl group has a carbon number of C3 to C4. 30 Substituted or unsubstituted cycloalkyl groups with a carbon number of C6 to C5 60 The substituted or unsubstituted aryl group has a carbon number of C6 to C6. 60 One of the substituted or unsubstituted heteroaryl groups; R3 can be connected to ring B to form a ring;

[0015] R4 indicates hydrogen, deuterium, halogen, or carbon atoms with a carbon number of C1 to C2. 30 The substituted or unsubstituted alkyl group has a carbon number of C3 to C4. 30 Substituted or unsubstituted cycloalkyl groups with a carbon number of C6 to C5 60 The substituted or unsubstituted aryl group has a carbon number of C6 to C6. 60 One of the substituted or unsubstituted heteroaryl groups;

[0016] X and Y independently represent NR5, O, or S, and R5 represents hydrogen, deuterium, halogen, and carbon atoms with C1 to C2 atoms. 30 The substituted or unsubstituted alkyl group has a carbon number of C3 to C4. 30 Substituted or unsubstituted cycloalkyl groups with a carbon number of C6 to C5 60 The substituted or unsubstituted aryl group has a carbon number of C6 to C6. 60 Substituted or unsubstituted heteroaryl groups with a carbon number of C6 to C5 60 Substituted or unsubstituted fused-ring aryl groups with a carbon number of C5 to C6. 60 One of the following: substituted or unsubstituted heterocyclic aryl, substituted or unsubstituted amino, or substituted or unsubstituted ether.

[0017] The substituents in ring A, ring B, R1, R2, R3, R4, and R5 may be the same or different, and each is independently selected from deuterium, halogen, cyano, and carbon atoms with C1 to C5. 10 The alkyl group has a carbon number of C6 to C6. 60 The aryl group has a carbon number of C6 to C6. 60 Fused ring aryl group, with C3 to C4 carbon atoms 30 One of the cycloalkyl groups, wherein two or more substituents can be linked together to form an aliphatic ring, an aromatic ring or a fused ring;

[0018] The hydrogen atoms in the compound shown in Formula I can be replaced by deuterium independently.

[0019] Furthermore, the amino group is selected from substituted or unsubstituted carbon atoms with numbers C1 to C2. 10 The alkylamino group, whether substituted or unsubstituted, has 6 to 10 carbon atoms. 20 Aromatic amino groups, substituted or unsubstituted carbon atoms, have 6 to 10 carbon atoms. 20 Arylamino groups, substituted or unsubstituted carbon atoms, C2-C3 24 One of the heteroaryl amino groups.

[0020] Furthermore, R3 indicates a carbon number of C1 to C2. 10 The substituted or unsubstituted alkyl group has a carbon number of C2 to C3. 10 Substituted or unsubstituted alkenyl groups, Each of the H atoms in the above structures can be independently replaced by F, D, straight-chain alkyl, branched alkyl, cycloalkyl, or phenyl.

[0021] The ring formed by R3 and ring B is one of the following: substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, or substituted or unsubstituted heteroaryl.

[0022] Furthermore, the compound of formula I is selected from one of the structures shown in formulas I-1 to I-6 below:

[0023]

[0024]

[0025] Furthermore, the ring A represents

[0026] Furthermore, the ring B represents Or the number of carbon atoms is C3 to C4. 15The cycloalkyl group, R6 represents aryl or alkyl; any non-adjacent C in the above structures can be independently replaced by N, and any H can be independently replaced by F, D, CN, straight-chain alkyl, branched alkyl, cycloalkyl, aryl, heteroaryl or aromatic amino.

[0027] Furthermore, the ring formed by the connection of two or more R1s is one of substituted or unsubstituted cycloalkyl or substituted or unsubstituted aryl; the ring formed by the connection of two or more R2s is one of substituted or unsubstituted cycloalkyl or substituted or unsubstituted aryl.

[0028] Furthermore, R1 and R2 each independently represent hydrogen and carbon atoms with numbers C1 to C2. 10 Substituted or unsubstituted alkyl groups R7 and R8 each independently represent carbon atoms ranging from C1 to C8. 10 The substituted or unsubstituted alkyl group has a carbon number of C3 to C4. 15 Substituted or unsubstituted cycloalkyl groups with a carbon number of C6 to C5 20 The substituted or unsubstituted aryl group, wherein Z represents O, S, C (R9), and R9 represents a carbon number of C1 to C2. 10 Substituted or unsubstituted alkyl groups.

[0029] Furthermore, R5 indicates a carbon number of C1 to C2. 10 Substituted or unsubstituted alkyl groups Each of the H atoms in the above structures can be independently replaced by F, D, straight-chain alkyl, branched-chain alkyl, cycloalkyl, or phenyl.

[0030] Furthermore, the compound represented by Formula I is selected from any one of the following compounds:

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059] In a second aspect, the present invention provides an organic electroluminescent device comprising an anode, a hole transport region, a light-emitting layer, an electron transport region, and a cathode sequentially disposed on a substrate; wherein the light-emitting layer comprises one or more polycyclic compounds as described above.

[0060] Furthermore, the light-emitting layer comprises a host material and a dopant material, wherein the dopant material comprises one or more polycyclic compounds as described above.

[0061] Furthermore, the organic electroluminescent device is a TADF superfluorescent device.

[0062] Beneficial effects of this invention:

[0063] This invention provides a polycyclic compound, a planar bis-boron nitrogen material. The invention introduces a bridged ring structure to reduce the electron-donating ability of nitrogen atoms, and further weakens this ability through a bridged ring and benzene ring structure, avoiding a redshift in the material's emission. Compared to the benzene ring, the twisted structure of the bridged ring weakens the intermolecular interactions caused by this planar configuration, which is more conducive to the dispersion of dopants in the host material, effectively avoiding fluorescence quenching and improving luminescence efficiency. Simultaneously, the use of a bis-boron framework allows the material to maintain a narrow half-width at half-maximum (WHM), resulting in devices fabricated using the compound of this invention exhibiting excellent performance in terms of efficiency and lifetime.

[0064] The compounds provided by this invention are suitable for blue host / dopant systems in the blue series of AM-OLEDs and organic electroluminescent devices. Organic electroluminescent devices containing these compounds have high external quantum efficiency and particularly excellent lifetime performance. Attached Figure Description

[0065] Figure 1 This is a schematic diagram of the structure of an organic electroluminescent device containing the polycyclic compound of the present invention;

[0066] Figure description: 1-substrate, 2-anode, 3-hole injection layer, 4-hole transport layer, 5-light-emitting auxiliary layer, 6-light-emitting layer, 7-electron transport layer, 8-electron injection layer, 9-cathode. Detailed Implementation

[0067] To better understand the content of this invention, a detailed description will be provided in conjunction with the accompanying drawings and embodiments.

[0068] The compounds of this invention are applicable to light-emitting elements, display panels, and electronic devices, particularly organic electroluminescent devices. The electronic devices described in this invention are devices comprising at least one layer containing at least one organic compound; the device may also comprise inorganic materials or layers formed entirely of inorganic materials. Preferably, the electronic devices are organic electroluminescent devices (OLEDs), organic integrated circuits (O-ICs), organic field-effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors (O-LETs), organic solar cells (O-SCs), organic dye-sensitized solar cells (O-DSSCs), organic optical detectors, organic photosensors, organic field quenching devices (O-FQDs), light-emitting electrochemical cells (LECs), organic laser diodes (O-lasers), and organic plasma emitting devices. Organic electroluminescent devices (OLEDs) are particularly preferred. A schematic diagram of an exemplary organic electroluminescent device is shown below. Figure 1 As shown.

[0069] Experimental Section

[0070] To better understand the content of this invention, the polycyclic compound, the preparation method of the compound, and the luminescent properties of the device will be explained in detail with reference to embodiments. Various chemical reactions can be applied to the synthesis method of the compound according to one embodiment of this invention. However, it should be noted that the synthesis method of the compound according to one embodiment of this invention is not limited to the synthesis method described below. Unless otherwise stated, subsequent synthesis is carried out in an anhydrous solvent under a protective gas atmosphere. Solvents and reagents can be purchased from conventional reagent suppliers.

[0071] compound

[0072] intermediate synthesis

[0073] The synthesis of intermediates is not limited to one method; halogen substituents can be adjusted according to cost requirements, making the synthesis of intermediate structures convenient and inexpensive.

[0074] Key structure synthesis:

[0075]

[0076] Under nitrogen protection, A-6 (40 g, 0.21 mol) and B-6 (26 g, 0.20 mol) were added to DCM (800 ml). The system was cooled to -10 °C, and then DCC (45.3 g, 0.22 mol) was slowly added dropwise. After the addition was complete, the reaction system was heated to 25 °C with stirring and maintained for 1 hour. After the reaction solution was filtered, 800 ml of deionized water was added to the filtrate, and the mixture was separated. After filtering the organic phase, water was removed by anhydrous sodium sulfate, and the organic solvent was removed by rotary evaporation. The crude product was purified by column chromatography, and the final product C-6 was obtained: 44.24 g (yield: 70%), MS (m / z) (M+): 316.

[0077] Under nitrogen protection, C-6 (44.24 g, 0.14 mol), D-6 (102.48 g, 0.84 mol), palladium chloride (2.4 g, 14 mmol), tri-tert-butylphosphide tetrafluoroborate (8.12 g, 28 mmol), and cesium carbonate (91.28 g, 0.28 mol) were added to toluene (500 ml). The reaction system was heated to 120 °C with stirring and maintained for 6 hours. 500 ml of deionized water was added, and the mixture was separated. After filtering the organic phase, water was removed by anhydrous sodium sulfate, and the organic solvent was removed by rotary evaporation. The crude product was purified by column chromatography to finally obtain product E-6: 15.34 g (yield: 35%), MS (m / z) (M+): 313.

[0078] Under nitrogen protection, E-6 (4.38 g, 14 mmol) and trifluoroacetic acid (7.45 g, 65 mmol) were added to DCM (20 ml). The reaction system was maintained at room temperature with stirring for 24 hours. 20 ml of deionized water was added, and the mixture was separated. After filtering the organic phase, water was removed by anhydrous sodium sulfate, and the organic solvent was removed by rotary evaporation. The crude product was purified by column chromatography to finally obtain product F-6: 2.09 g (yield: 70%), MS (m / z) (M+): 213.

[0079] Synthesis of other intermediate fragments

[0080]

[0081] Under nitrogen protection, R-1 (140.40 g, 1.3 mmol) was added to acetic acid (1000 ml). The system temperature was slowly raised to 60 °C with stirring. Then, S-1 (145.60 g; 1.3 mmol) was slowly added dropwise. The reaction system was then heated to 118 °C with stirring and maintained for 8 hours. After cooling to room temperature, 500 ml of water was added, and sodium hydroxide was slowly added to adjust the pH to neutral. The mixture was extracted with ethyl acetate and separated. The organic phase was filtered and dehydrated with anhydrous sodium sulfate. After removing the organic solvent by rotary evaporation, the crude product was obtained. After purification by column chromatography, 185 g of solid was obtained. Under nitrogen protection, the solid was added to 1.5 L of toluene, cooled to -20 °C, and methyl lithium solution (1.6 M, 765 mL, 1.22 mol) was slowly added dropwise with stirring. After the addition was complete, stirring was continued for 3 h. Then, the mixture was slowly raised to room temperature and 1 L of water was added. After filtering the organic phase, water was removed by anhydrous sodium sulfate. After removing the organic solvent by rotation, the crude product was purified by column chromatography, and finally, product T-1 was obtained: 104.52 g (yield: 40%), MS (m / z) (M+): 201.

[0082]

[0083] H-1 (158.5 g, 0.5 mol), G-1 (84.5 g, 0.45 mol), and sodium tert-butoxide (52.8 g, 0.55 mol) were added to toluene (1.5 L). Then, under nitrogen protection, palladium dibenzylacetone (4.6 g, 5 mmol) and SPhos (4.1 g, 10 mmol) were introduced. The reaction mixture was then heated to 110 °C, refluxed, and maintained for 8 hours. After cooling to room temperature, the mixture was quenched with water and separated. The organic phase was filtered, dried over anhydrous sodium sulfate, and the solvent was removed by rotary evaporation. The crude product was purified by column chromatography. The final product I-1 was 129.24 g (yield: 80%), MS (m / z) (M+): 359.

[0084]

[0085] I-1 (17.95 g, 50 mmol), F-6 (10.65 g, 50 mmol), and sodium tert-butoxide (5.28 g, 55 mmol) were added to toluene (150 mL). Under nitrogen protection, palladium dibenzylacetone (0.46 g, 0.5 mmol) and SPhos (0.41 g, 1 mmol) were introduced. The reaction mixture was then heated to 110 °C, refluxed, and maintained for 8 hours. After cooling to room temperature, the mixture was quenched with water and separated. The organic phase was filtered, dried over anhydrous sodium sulfate, and the solvent was removed by rotary evaporation. The crude product was purified by column chromatography. The final product was J-6: 20.87 g (yield: 85%), MS (m / z) (M+): 491.

[0086]

[0087] I-1 (17.90 g, 50 mmol), G-2 (8.35 g, 50 mmol), and sodium tert-butoxide (5.28 g, 55 mmol) were added to toluene (150 mL). Under nitrogen protection, palladium dibenzylacetone (0.46 g, 0.5 mmol) and SPhos (0.41 g, 1 mmol) were introduced. The reaction mixture was then heated to 110 °C, refluxed, and maintained for 8 hours. After cooling to room temperature, the mixture was quenched with water and separated. The organic phase was filtered, dried over anhydrous sodium sulfate, and the solvent was removed by rotary evaporation. The crude product was purified by column chromatography. The final product was K-1: 18.47 g (yield: 83%), MS (m / z) (M+): 445.

[0088] This method can also be used to prepare K-26, K-36, K-41, K-63, and K-186.

[0089]

[0090] Q-1 (118 g; 0.5 mol), M-1 (97.65 g; 1.05 mol), and sodium tert-butoxide (105.60 g, 1.1 mol) were added to toluene (1.5 L). Then, under nitrogen protection, a toluene solution of dibenzylacetone palladium (4.58 g, 5 mmol) and tri-tert-butylphosphide (0.5 M, 4.04 g, 10 mmol) was introduced. The reaction mixture was then heated to 110 °C, refluxed, and maintained for 8 hours. After cooling to room temperature, the mixture was quenched with water and separated. The organic phase was filtered, dried over anhydrous sodium sulfate, and the solvent was removed by rotary evaporation. The crude product was purified by column chromatography. The final product N-1 was obtained: 97.5 g (yield: 75%), MS (m / z) (M+): 260.

[0091] L-111 Synthesis

[0092]

[0093] Step 1: Under nitrogen protection, H-111 (12.27 g; 0.03 mol), Q-111 (4.644 g; 0.036 mol), cuprous iodide (0.57 g, 3 mmol), 1,10-phenanthroline (0.54 g, 3 mmol), and potassium phosphate (8.90 g, 42 mmol) were added to DMF (50 mL). The reaction system was then heated to 153 °C, refluxed, and maintained for 5 hours. After cooling to room temperature, the mixture was quenched with water and separated. The organic phase was filtered and dried over anhydrous sodium sulfate. The solvent was removed by rotary evaporation, and the crude product was purified by column chromatography. The final product was U-111: 8.22 g (yield: 67%), MS (m / z) (M+): 409.

[0094] Step 2: The method is similar to the first step in L-111, except that U-111 (12.27 g, 30 mmol) replaces H-111, and M-111 (2.82 g, 36 mmol) replaces Q-111, finally yielding product V-111: 7.33 g (yield: 65%), MS (m / z) (M+): 376.

[0095] Step 3: The method is similar to K-1, except that V-111 (18.80 g, 50 mmol) replaces I-1, and G-1 (8.45 g, 50 mmol) replaces G-2, finally yielding product W-111: 18.56 g (yield: 80%), MS (m / z) (M+): 464.

[0096] Step 4: The method is similar to K-1, except that W-111 (23.20 g, 50 mmol) replaces I-1, and M-1 (4.65 g, 50 mmol) replaces G-2, finally yielding product L-111: 19.54 g (yield: 75%), MS (m / z) (M+): 521.

[0097] The synthesis method of L-121 is similar to that of L-111, and will not be described in detail here.

[0098] Synthesis Examples

[0099] Example 1

[0100]

[0101] Step 1: J-6 (24.55 g, 50 mmol), N-1 (14.30 g, 55 mmol), and sodium tert-butoxide (5.28 g, 55 mmol) were added to toluene (150 mL). Then, under nitrogen protection, a toluene solution of dibenzylacetone palladium (1.37 g, 1.5 mmol) and tri-tert-butylphosphide (0.5 M, 1.21 g, 3 mmol) was introduced. The reaction system was then heated to 110 °C, refluxed, and maintained for 8 hours. After cooling to room temperature, the mixture was quenched with water and separated. The organic phase was filtered, dried over anhydrous sodium sulfate, and the solvent was removed by rotary evaporation. The crude product was purified by column chromatography. The final product was X-6: 27.89 g (yield: 78%), MS (m / z) (M+): 715.

[0102] Step 2: X-6 (21.45 g, 30 mmol), K-1 (13.35 g, 30 mmol), and sodium tert-butoxide (3.17 g, 33 mmol) were added to toluene (100 mL). Then, under nitrogen protection, a toluene solution of dibenzylacetone palladium (0.82 g, 0.9 mmol) and tri-tert-butylphosphide (0.5 M, 0.73 g, 1.8 mmol) was introduced. The reaction system was then heated to 110 °C, refluxed, and maintained for 8 hours. After cooling to room temperature, the mixture was quenched with water and separated. The organic phase was filtered, dried over anhydrous sodium sulfate, and the solvent was removed by rotary evaporation. The crude product was purified by column chromatography. The final product was Y-6: 26.95 g (yield: 80%), MS (m / z) (M+): 1123.

[0103] Step 3: Under nitrogen protection, Y-6 (22.46 g, 20 mmol) was dissolved in o-dichlorobenzene (200 mL) in a reaction flask. Boron tribromide (20.04 g, 80 mmol) was slowly added dropwise at room temperature. The reaction system was then heated to 180 °C and stirred for 20 hours. After cooling to room temperature, N,N-diisopropylethylamine (12.83 mL, 75 mmol) was added at 0 °C. The mixture was stirred for 2 hours, and the solvent was removed by rotary evaporation. The crude product was recrystallized from n-heptane, acetone, and toluene to finally obtain product Z-6: 3.42 g (yield: 15%), MS (m / z) (M+): 1139.

[0104] Example 2

[0105]

[0106] Step 1: The method is similar to the first step in Example 1, except that J-26 (23.15g, 50mmol) is replaced with J-6, and the final product X-26 is obtained: 27.48g (yield: 80%), MS (m / z) (M+): 687.

[0107] Step 2: The method is similar to Step 2 in Example 1, except that X-26 (20.61g, 30mmol) is replaced with X-6, and K-26 (13.41g, 30mmol) is replaced with K-1. The final product Y-26 was obtained: 24.68g (yield: 75%), MS (m / z) (M+): 1097.

[0108] Step 3: The method is similar to step 3 in Example 1, except that Y-26 (21.94 g, 20 mmol) is used instead of Y-6. The final product obtained is Z-26: 3.12 g (yield: 14%), MS (m / z) (M+): 1113.

[0109] Example 3

[0110]

[0111] Step 1: The method is similar to Step 2 in Example 1, except that X-26 (20.61g, 30mmol) is replaced with X-6, and K-36 (14.37g, 30mmol) is replaced with K-1. The final product Y-36 was obtained: 22.04g (yield: 65%), MS (m / z) (M+): 1130.

[0112] Step 2: The method is similar to Step 3 in Example 1, except that Y-36 (22.60 g, 20 mmol) is used instead of Y-6. The final product obtained is Z-36: 3.66 g (yield: 16%), MS (m / z) (M+): 1145.

[0113] Example 4

[0114]

[0115] Step 1: The method is similar to Step 2 in Example 1, except that X-26 (20.61g, 30mmol) is replaced with X-6, and K-41 (13.59g, 30mmol) is replaced with K-1. The final product Y-41 was obtained: 23.88g (yield: 70%), MS (m / z) (M+): 1137.

[0116] Step 2: The method is similar to Step 3 in Example 1, except that Y-6 is replaced with Y-41 (22.74 g, 20 mmol). The final product obtained is Z-41: 3.00 g (yield: 13%), MS (m / z) (M+): 1153.

[0117] Example 5

[0118]

[0119] Step 1: J-26 (46.30 g, 100 mmol), N-1 (13.00 g, 50 mmol), and sodium tert-butoxide (10.56 g, 110 mmol) were added to toluene (150 mL). Then, under nitrogen protection, a toluene solution of dibenzylacetone palladium (2.74 g, 3 mmol) and tri-tert-butylphosphide (0.5 M, 2.42 g, 6 mmol) was introduced. The reaction system was then heated to 110 °C, refluxed, and maintained for 8 hours. After cooling to room temperature, the mixture was quenched with water and separated. The organic phase was filtered, dried over anhydrous sodium sulfate, and the solvent was removed by rotary evaporation. The crude product was purified by column chromatography. The final product was Y-46: 36.17 g (yield: 65%), MS (m / z) (M+): 1113.

[0120] Step 2: The method is similar to Step 3 in Example 1, except that Y-6 is replaced with Y-46 (22.74 g, 20 mmol). The final product obtained is Z-46: 3.39 g (yield: 15%), MS (m / z) (M+): 1129.

[0121] Example 6

[0122]

[0123] Step 1: The method is similar to Step 2 in Example 1, except that K-63 (15.09 g, 30 mmol) is used instead of K-1. The final product Y-36 was obtained: 25.86 g (yield: 73%), MS (m / z) (M+): 1181.

[0124] Step 2: The method is similar to Step 3 in Example 1, except that Y-6 is replaced with Y-6 (22.60 g, 20 mmol). The final product obtained is Z-63: 2.39 g (yield: 10%), MS (m / z) (M+): 1197.

[0125] Example 7

[0126]

[0127] Step 1: The method is similar to Step 2 in Example 1, except that L-111 (15.63g, 30mmol) replaces X-6 and J-26 (13.89g, 30mmol) replaces K-1. The final product obtained is Y-111: 19.32g (yield: 68%), MS (m / z) (M+): 947.

[0128] Step 2: The method is similar to Step 3 in Example 1, except that Y-6 is replaced with Y-111 (18.94 g, 20 mmol). The final product obtained is Z-111: 2.89 g (yield: 15%), MS (m / z) (M+): 963.

[0129] Example 8

[0130]

[0131] Step 1: The method is similar to Step 2 in Example 1, except that L-121 (18.84g, 30mmol) replaces X-6, and J-26 (13.89g, 30mmol) replaces K-1. The final product obtained is Y-121: 23.08g (yield: 73%), MS (m / z) (M+): 1054.

[0132] Step 2: The method is similar to Step 3 in Example 1, except that Y-6 is replaced with Y-121 (20.08g, 20mmol). The final product obtained is Z-121: 2.14g (yield: 10%), MS (m / z) (M+): 1070.

[0133] Example 9

[0134]

[0135] Step 1: The method is similar to the first step in Example 1, except that J-186 (23.65g, 50mmol) is replaced with J-6, and the final product X-186 is obtained: 28.58g (yield: 82%), MS (m / z) (M+): 697.

[0136] Step 2: The method is similar to Step 2 in Example 1, except that X-186 (20.91g, 30mmol) is replaced with X-6, and K-186 (14.67g, 30mmol) is replaced with K-1. The final product obtained is Y-186: 27.60g (yield: 80%), MS (m / z) (M+): 1150.

[0137] Step 3: The method is similar to step 3 in Example 1, except that Y-186 (23.00g, 20mmol) is used instead of Y-6. The final product obtained is Z-186: 3.73g (yield: 16%), MS (m / z) (M+): 1165.

[0138] Example 10

[0139]

[0140] Step 1: The method is similar to Step 1 in Example 5, except that J-221 (46.30 g, 100 mmol) is replaced with J-6. The final product obtained is Y-221: 30.87 g (yield: 70%), MS (m / z) (M+): 882.

[0141] Step 2: Under nitrogen protection, Y-221 (17.64 g, 20 mmol) and anhydrous tert-butylbenzene (200 mL) were placed in a reaction flask and cooled to -78 °C. A pentane solution of tert-butyllithium (6.5 g, 100 mmol) was slowly added dropwise to the stirred reaction system. The temperature was slowly raised to -30 °C and stirred for 2 hours. Then, boron tribromide (24.92 g, 0.1 mol) was added dropwise. The reaction system was then heated to room temperature and stirred for 2 hours. N,N-diisopropylethylamine (25.2 g, 0.2 mol) was added, and the temperature was raised to 145 °C and maintained for 4 hours. After cooling to room temperature, a saturated sodium bicarbonate aqueous solution was added, and the mixture was extracted with ethyl acetate. The organic phase was filtered and dried over anhydrous sodium sulfate. The solvent was removed by rotary evaporation, and the crude product was purified by column chromatography. The final product was Z-221: 1.66 g (yield: 10%), MS (m / z) (M+): 829.

[0142] OLED manufacturing and characterization

[0143] Device Examples

[0144] The organic electroluminescent device provided by the present invention includes an anode, a hole transport region, a light-emitting layer, an electron transport region, and a cathode sequentially disposed on a substrate.

[0145] Furthermore, the hole transport region includes a hole transport layer and a light-emitting auxiliary layer; the electron transport region includes an electron transport layer and an electron injection layer.

[0146] Furthermore, the light-emitting layer is composed of a host material and doped materials, and the host material of the light-emitting layer can be composed of one molecular material or multiple molecular materials.

[0147] The polycyclic compound described in this invention can be used as one or more layers of the above-mentioned organic electroluminescent device, preferably as a doping material for the light-emitting layer of the device.

[0148] In this embodiment, the anode uses a commonly used anode material in the art, such as ITO, Ag, or their multilayer structures. The hole injection unit uses a commonly used hole injection material in the art, and is doped with F4TCNQ, HATCN, NDP-9, etc. The hole transport unit uses a commonly used hole transport material in the art. The light-emitting unit uses a commonly used light-emitting material in the art, for example, it can be composed of a host material and an emitting guest material, the emitting guest material can be an organic material such as a pyrene compound, or a metal complex (such as metal Ir, Pt, etc.). The electron transport unit uses a commonly used electron transport material in the art. The electron injection layer uses a commonly used electron injection material in the art, such as Liq, LiF, Yb, etc. The cathode uses a commonly used material in the art, such as metal Al, Ag, or metal mixtures (Ag-doped Mg, Ag-doped Ca, etc.).

[0149] The electrode fabrication method and the deposition method of each functional layer in this embodiment are conventional methods in the art, such as vacuum thermal evaporation or inkjet printing, and will not be described in detail here. Only some process details and testing methods in the fabrication process are supplemented as follows:

[0150] Device Example 1

[0151] In the fabrication of blue light-emitting devices, firstly, a hole injection layer is formed on the ITO layer (anode) formed on the substrate by vacuum deposition of HTL and F4TCNQ (mass ratio 97:3) with a thickness of 10 nm. Secondly, on the hole injection layer, HTL is vacuum deposited with a thickness of 120 nm to form a hole injection layer. Next, on the hole transport layer, B-prime is vacuum deposited with a thickness of 10 nm to form a light-emitting auxiliary layer. Then, on the light-emitting auxiliary layer, a mixture of BH as the host and Z-6 as the dopant with a mass ratio of 98:2 is vacuum deposited with a thickness of 20 nm to form a light-emitting layer. Next, on the light-emitting layer, ET-01 and Liq (mass ratio 1:1) are vacuum deposited with a thickness of 35 nm to form an electron transport layer. Then, LiF is deposited with a thickness of 0.2 nm on the electron transport layer to form an electron injection layer. Finally, aluminum (Al) is deposited with a thickness of 150 nm on the electron injection layer to form a cathode, thus fabricating a blue organic light-emitting device.

[0152]

[0153] Organic electroluminescent devices were prepared by using the above method with the compounds described in the examples. Among them, blue organic electroluminescent devices were prepared by replacing Z-6 with Z-18, Z-22, Z-74, Z-98, Z-106, Z-124, Z-153, Z-169, and Z-268, as described in Examples 2 to 10.

[0154] Device Comparison

[0155] Using the above method, an organic light-emitting device was fabricated from the comparative compound BD as a device comparison example. Specifically, a blue organic light-emitting device was fabricated using BD instead of Z-6 as a device comparison example.

[0156]

[0157] The OLED devices described above were tested using standard methods. For this purpose, J = 10 mA / cm² was used. 2The driving voltage, luminance, electroluminescent current efficiency (in cd / A), and external quantum efficiency (EQE, in percentage) of the organic electroluminescent device were determined at a given current density, calculated as a function of luminescence density from the current / voltage / luminescence density characteristic line (IVL characteristic line) exhibiting Lambertian emission characteristics, and the emission spectrum. The lifetime LT was defined as the time after which, when operating at a constant current J, the luminance decreased from the initial luminance L0 to a specific proportion L1; J = 50 mA / cm². 2 The statement L1 = 90% refers to a value of 50 mA / cm. 2 When operating below the threshold, the luminous intensity decreases to 90% of its initial value L0 after time LT. Similarly, J = 20 mA / cm² 2 L1 = 80% means that at 20 mA / cm 2 When operating below the threshold, the luminous intensity drops to 80% of its initial value L0 after time LT.

[0158] The data for various OLED devices are summarized in Table 1. The parameters of the examples and comparative examples are compared to demonstrate the performance data of the various OLED devices.

[0159] The testing instruments and methods used to perform performance testing on the OLED devices of the above embodiments and comparative examples are as follows:

[0160] Brightness was tested using a PhotoResearch PR-635 spectral scanner;

[0161] Current density and turn-on voltage: tested using a Keithley 2400 digital source meter;

[0162] Life test: The LT-96ch life test device was used.

[0163] The performance test results of the above devices are listed in Table 1.

[0164] Table 1 Performance test results of blue light devices

[0165]

[0166] As shown in Table 1 above, the device performance test results reveal that the organic electroluminescent device prepared from the polycyclic organic compound of this invention exhibits lower driving voltage, significantly improved external quantum efficiency, and significantly increased lifetime compared to the comparative device. This is because the unique bridged ring structure introduced in this invention leads to a more distorted molecular planar configuration, weakening intermolecular interactions and reducing concentration quenching, thereby significantly improving the external quantum efficiency and lifetime of the device. This demonstrates that the polycyclic organic compound protected by this invention is a high-performance blue luminescent material with practical value.

[0167] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A polycyclic compound, characterized by, The polycyclic compound is selected from the following compounds: Z-213、 Z-219、 Z-220、 Z-221、 Z-222、 Z-226、 Z-227、 Z-254、 Z-294、 Z-296、 Z-297、 Z-306、 Z-320。 2. An organic electroluminescent device, characterized in that, It includes an anode, a hole transport region, a light-emitting layer, an electron transport region, and a cathode sequentially disposed on a substrate; the light-emitting layer includes a host material and a dopant material, wherein the dopant material includes one or more polycyclic compounds as described in claim 1.

3. The organic electroluminescent device according to claim 2, characterized in that The organic electroluminescent device is a TADF superfluorescent device.

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