A phosphorus-containing polycyclic light-emitting compound, a preparation method thereof and an organic electroluminescent device

Abstract

The present application relates to a kind of phosphorus-containing polycyclic luminous compounds, which can be used as a dopant compound in the emitting layer of OLED device in cooperation with host material.The introduction of pentavalent phosphorus atom in its highly condensed nucleus improves quantum efficiency.The structure is easy to modify, with wide band gap, excellent charge transport capacity, high thermal stability and morphological stability.The device prepared by the present application has the performance advantages of high efficiency and long life.

Description

Technical Field

[0001] This invention relates to the field of organic electroluminescent device technology, and more specifically to a phosphorus-containing polycyclic luminescent compound, its preparation method, and an organic electroluminescent device. Background Technology

[0002] Organic light-emitting diodes (OLEDs) are self-emissive devices in which electrons injected from the electron injection electrode (cathode) recombine with holes injected from the hole injection electrode (anode) in the emissive layer to form excitons, which emit light while releasing energy. Such OLEDs offer advantages such as low driving voltage, high brightness, wide viewing angle, and short response time, and can be applied to full-color flat panel displays. Due to these advantages, OLEDs have attracted attention as a next-generation light source.

[0003] The emitting layer of an OLED consists of a host / doped material doped with luminescent materials. In such a layer, excitons can be efficiently generated from the charge injected into the host. The energy of the generated excitons can then be transferred to the doped material, resulting in efficient light emission. To achieve maximum efficiency in the emitting layer, the band gap between the host and the dopant must be appropriately tuned so that holes and electrons can move to the dopant via stable electrochemical pathways to form excitons. Especially for blue OLEDs, improving luminous efficiency and extending lifetime are urgent industry expectations.

[0004] Therefore, the purpose of this invention is to provide a phosphorus-containing polycyclic luminescent compound as a dopant in the luminescent layer, thereby providing an organic light-emitting device with high luminous efficiency and long lifetime. Summary of the Invention

[0005] In view of this, the present invention provides a phosphorus-containing polycyclic luminescent compound, a method for preparing the same, and an organic electroluminescent device. The organic electroluminescent device obtained using the aforementioned fluorescent compound as a blue fluorescent dopant exhibits long lifetime, high efficiency, and good stability.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A phosphorus-containing polycyclic luminescent compound, the general structural formula of which is shown in Formula I:

[0008]

[0009] Among them, rings A, B, and C may or may not be present, and may be fused with adjacent benzene rings at any position where fusion is possible; rings A, B, and C are each independently selected from C6-C12 aromatic rings;

[0010] m and n are each independently selected from integers between 0 and 4; p is selected from integers between 0 and 3;

[0011] La, Lb, and Lc are each independently selected from the linking bond, substituted or unsubstituted C6-C18 arylene or substituted or unsubstituted 3-18 heteroarylene;

[0012] Ar1-Ar6 are each independently selected from substituted or unsubstituted C6-C25 aryl groups, substituted or unsubstituted 3-20 heteroaryl groups, whose heteroatoms are selected from oxygen (O), nitrogen (N), sulfur (S); substituted or unsubstituted 3-10 heteroarylamine groups, whose heteroatoms are selected from oxygen (O), nitrogen (N), sulfur (S); or substituted or unsubstituted C6-C30 arylamine groups.

[0013] Preferably, m = n.

[0014] Preferably, La, Lb, and Lc are each independently selected from linking bonds, phenylene, biphenylene, or naphthylene.

[0015] In the above terms, "substitution" means that the hydrogen atom bonded to the carbon atom of the compound becomes another substituent, and there is no restriction on the position of substitution, as long as the position is where the hydrogen atom is substituted (i.e., the position where the substituent can substitute), and when two or more substituents are substituted, the two or more substituents can be the same as or different from each other.

[0016] The "substituted" in "substituted or unsubstituted" mentioned above can preferably be one or more of the following: deuterium, cyano, halogen, nitro, hydroxyl, phosphate, boroalkyl, silyl, C1-C8 alkyl, C2-C15 alkenyl, C2-C10 alkynyl, C6-C20 aryl, C3-C10 heteroaryl, C1-C10 alkoxy, and C6-C20 arylamino.

[0017] Preferably, each of Ar1-Ar6 is independently selected from the following structures:

[0018]

[0019]

[0020] Preferably, the phosphorus-containing polycyclic compound is specifically shown in formulas (II) to (VII):

[0021]

[0022] More preferably, the phosphorus-containing polycyclic compounds are specifically as shown in formulas (II-a) to (II-j), (III-a) to (III-j), and (IV-a) to (IV-f):

[0023]

[0024]

[0025] Specifically, the phosphorus-containing polycyclic compounds include the following general structural formulas:

[0026]

[0027]

[0028]

[0029]

[0030] Another object of the present invention is to provide a method for preparing the above-mentioned phosphorus-containing polycyclic luminescent compound, the synthetic route of which is as follows:

[0031]

[0032] In the above formulas, the rings AC, m, n, p, La, Lb, Lc, and Ar1-Ar6 are represented in the same way as in Formula I; where X represents a halogen.

[0033] Specific preparation methods include:

[0034] Step 1: Preparation of Intermediate 1 (PCl3)

[0035] Under nitrogen protection, raw material a was dissolved in tetrahydrofuran. The solution was cooled to -78°C, and a tetrahydrofuran solution of n-butyllithium was slowly added dropwise. The mixture was stirred for 1-5 hours, and phosphorus trichloride was slowly added dropwise. After the reaction solution was restored to room temperature, it was heated under reflux for 1-5 hours. The solid was filtered off under nitrogen, and the filtrate was concentrated under reduced pressure. The crude product obtained was purified by silica gel column chromatography. The intermediate 1 was dissolved in tetrahydrofuran for later use.

[0036] Step 2, Preparation of Intermediate 2 (Introduction of NO2)

[0037] Under a nitrogen stream, raw material b was dissolved in tetrahydrofuran and stirred at -78°C for 0.5-5 hours. A tetrahydrofuran solution of n-butyllithium was slowly added dropwise, and the mixture was stirred for 1-5 hours. A tetrahydrofuran solution of intermediate 1 obtained in the first step was slowly added dropwise, and the mixture was reacted for 1-5 hours. The reaction solution was then brought back to room temperature and stirred overnight. Water was added to the reaction solution and stirred for 10-50 minutes. The mixture was allowed to stand and separated. The filtrate was extracted with ethyl acetate, and the organic layers were combined. The organic layers were concentrated under reduced pressure, and the crude product was purified by silica gel column chromatography.

[0038] The solid obtained above was dissolved in ethyl acetate and cooled to 0°C. Hydrogen peroxide aqueous solution was slowly added dropwise. The reaction solution was cooled to room temperature and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography to obtain intermediate 2.

[0039] Step 3, Preparation of Intermediate 3 (NH2ization)

[0040] Intermediate 2, Pd / C catalyst and ethanol were added to a high-pressure reactor, hydrogen was introduced, and the mixture was heated and stirred for 1-10 hours. The solid was filtered off after cooling, the filtrate was concentrated under reduced pressure, and the crude product of intermediate 3 was obtained by silica gel column chromatography.

[0041] Step 4: Preparation of Intermediate 4 (Ring Sealing)

[0042] Intermediate 3 was dissolved in a sulfuric acid / acetic acid mixed solution. Sodium nitrite was added while keeping the temperature below 10°C. After adding sodium nitrite, the temperature was gradually restored to room temperature, and then stirred at room temperature for 5-24 hours. The reaction solution was neutralized with sodium carbonate, extracted with toluene and ethyl acetate, and the organic layer was washed once with water. It was then dried with anhydrous sodium sulfate and concentrated to obtain a crude product. The crude product was purified to obtain intermediate 4.

[0043] Step 5: Preparation of the product (introduction of triarylamine)

[0044] Under nitrogen protection, intermediate 4 and raw material e were dissolved in toluene solution, and tris(dibenzylacetone)dipalladium, tri-tert-butylphosphine, and sodium tert-butoxide were added. The mixture was stirred until homogeneous, heated to 90°C, and refluxed for 1-10 hours. After the reaction was completed, the temperature was slightly lowered to 60-80°C, and the mixture was filtered with diatomaceous earth to remove salts and catalysts. The filtrate was cooled to room temperature and washed three times with water, retaining the organic phase. The aqueous phase was then extracted with ethyl acetate. The combined organic phases were dried with anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The remaining substances were purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (dichloromethane:petroleum ether volume ratio = 10:4) to finally obtain the phosphorus-containing polycyclic luminescent compound.

[0045] By replacing reactants a and b in the above synthetic route with reactants c and d containing B(OH)2 groups, the triarylamine groups are first introduced, followed by the formation of the parent nucleus. The synthetic route is as follows:

[0046]

[0047] In the above formulas, the rings AC, m, n, p, La, Lb, Lc, and Ar1-Ar6 are represented in the same way as in Formula I; where X represents a halogen.

[0048] Step 1: Preparation of Intermediate II-1 and Intermediate II-2

[0049] Under nitrogen protection, raw material c and raw material d were independently dissolved in toluene solution, and then raw material e with the target structure was added accordingly. Palladium catalyst, phosphine ligand and sodium tert-butoxide were added to each, stirred evenly, heated and refluxed to prepare intermediate II-1 and intermediate II-2.

[0050] In particular, when raw material c is not readily available, the raw materials and their reaction sequence with raw material e can be adjusted to prepare intermediate II-1;

[0051] Step 2, Preparation of Intermediate II-3 (+PCl3)

[0052] Under nitrogen protection, intermediate II-1 was dissolved in tetrahydrofuran, and a tetrahydrofuran solution of n-butyllithium was slowly added dropwise. After stirring for several hours, phosphorus trichloride was slowly added dropwise. After the reaction solution was restored to room temperature, it was heated under reflux for 1 hour. The solid was filtered off under nitrogen, and the filtrate was concentrated under reduced pressure to obtain intermediate II-3, which was dissolved in tetrahydrofuran for later use.

[0053] Step 3: Preparation of Intermediate II-4 (Introduction of NO2)

[0054] Under nitrogen protection, intermediate II-2 was dissolved in tetrahydrofuran, and a tetrahydrofuran solution of n-butyllithium was slowly added dropwise while stirring for 1-5 hours. Then, a tetrahydrofuran solution of intermediate II-3 obtained in the first step was slowly added dropwise while stirring for 1-5 hours. After reacting for 1-5 hours, the reaction solution was brought back to room temperature and stirred overnight. Water was added to the reaction solution and stirred for 10-60 minutes. The mixture was allowed to stand and separated. The filtrate was extracted with ethyl acetate, and the organic layers were combined. The organic layers were concentrated under reduced pressure and purified by silica gel column chromatography to obtain the crude product.

[0055] The solid obtained above was dissolved in ethyl acetate and cooled to 0°C. Hydrogen peroxide aqueous solution was slowly added dropwise, the reaction solution was cooled to room temperature and concentrated under reduced pressure, and the crude product of intermediate II-4 was obtained by silica gel column chromatography.

[0056] Step 4: Synthesis of intermediate II-5 (NH2ization)

[0057] Intermediate II-4, Pd / C catalyst and ethanol were added to a high-pressure reactor, hydrogen was introduced, and the mixture was heated and stirred for 1-10 hours. The solid was filtered off after cooling, the filtrate was concentrated under reduced pressure, and the crude product of intermediate II-5 was obtained by silica gel column chromatography.

[0058] Step 5: Synthesis of the final product

[0059] Intermediate II-5 was dissolved in a sulfuric acid / acetic acid mixed solution. Sodium nitrite was added while maintaining the temperature below 10°C. After adding sodium nitrite, the temperature was gradually restored to room temperature, and then stirred at room temperature for 5-24 hours. The reaction solution was neutralized with sodium carbonate, extracted with toluene and ethyl acetate, and the organic layer was washed once with water. It was then dried with anhydrous sodium sulfate and concentrated to obtain a crude product. The crude product was purified to remove impurities and finally obtain the phosphorus-containing polycyclic luminescent compound.

[0060] In the two synthetic routes above, the reaction can be carried out in the order of activity of I>Br>Cl, and the starting materials can be selected, the reaction conditions controlled, and the product structure adjusted.

[0061] The present invention also provides an organic electroluminescent device comprising an organic layer, more specifically, the light-emitting layer of the organic layer comprising a host material and a dopant material, wherein the dopant material comprises the aforementioned phosphorus-containing polycyclic compound.

[0062] The organic electroluminescent device of the present invention can have a structure comprising an organic layer including a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting auxiliary layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer. However, the structure of the organic light-emitting element is not limited to this, and it can contain fewer or more organic layers.

[0063] According to one embodiment of this specification, the above-mentioned organic layer includes a light-emitting layer, which contains a compound of formula I prepared according to the present invention.

[0064] The first electrode serves as the anode, which preferably comprises a material with a high work function, such as indium tin oxide (ITO) or indium zinc oxide (IZO). Since the lifespan of the device of the present invention is shortened in the presence of water and / or air, the device is appropriately (depending on the application) structured, provided with contacts, and finally sealed.

[0065] The hole injection layer is a layer that injects holes from the electrode. The preferred hole injection material is a compound that has the ability to transport holes, has a hole injection effect from the anode, has an excellent hole injection effect on the light-emitting layer or light-emitting material, and prevents excitons generated in the light-emitting layer from migrating to the electron injection layer or electron injection material.

[0066] Hole transport materials are materials that can receive holes from the anode or hole injection layer and transport the holes to the light-emitting layer, and have high hole mobility; specific examples include, but are not limited to, arylamine-based organic materials, conductive polymers, block copolymers having both conjugated and non-conjugated parts.

[0067] An electron blocking layer can be disposed between the hole transport layer and the light-emitting layer. Materials known in the art, such as arylamine-based organic materials, can be used as the electron blocking layer.

[0068] The luminescent layer is a material capable of receiving and combining holes and electrons from the hole transport layer and the electron transport layer, respectively, to emit light in the visible light region. It is preferably a material with high quantum efficiency for fluorescence or phosphorescence. The luminescent layer comprises a host material and dopant materials.

[0069] The aforementioned luminescent layer may comprise a host material and a dopant material. The host material may be an aromatic fused-ring derivative or a heterocyclic compound. Specifically, aromatic fused-ring derivatives include anthracene derivatives, pyrene derivatives, naphthalene derivatives, pentane derivatives, phenanthrene compounds, and fluoranthene compounds, while heterocyclic compounds include carbazole derivatives, dibenzofuran derivatives, ladder-type furan compounds, and pyrimidine derivatives, but are not limited to these.

[0070] The dopant materials mentioned above include aromatic amine derivatives, styrylamine compounds, boron complexes, fluoranthene compounds, and metal complexes.

[0071] The mass ratio of the main material to the dopant material is 90–99.5:0.5–10.

[0072] Hole-blocking layer materials can be compounds known in the prior art that have hole-blocking effects, such as phenanthrene-corrosion derivatives like BCP, oxazole derivatives, triazole derivatives, triazine derivatives, etc., but are not limited to these.

[0073] The electron transport layer can promote electron transport and can use compounds known in the prior art that have electron transport functions, such as Al complexes of 8-hydroxyquinoline; complexes containing Alq3; organic free radical compounds; hydroxyflavonoid-metal complexes, etc.

[0074] The electron injection layer can promote electron injection and has the ability to transport electrons, preventing excitons generated in the light-emitting layer from migrating to the hole injection layer. The electron injection materials used in this invention include, but are not limited to, fluorenone, anthraquinone dimethane, biphenylquinone, thiamethane dioxide, azoles, diazoles, triazoles, imidazoles, perylenetetracarboxylic acid, fluorenemethane, anthrone, and their derivatives, metal complexes, nitrogen-containing five-membered ring derivatives, etc.

[0075] The second electrode, serving as the cathode, is typically made of a material with a low work function to facilitate electron injection into the organic material layer; for example, magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead, or alloys thereof.

[0076] Depending on the material used, the organic light-emitting element of the present invention can be a top-emitting type, a bottom-emitting type, or a bidirectional-emitting type.

[0077] The device described in this invention can be used in organic light-emitting devices, organic solar cells, electronic paper, organic photoreceptors, or organic thin-film transistors.

[0078] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects:

[0079] Using the compounds of this invention as blue light doping materials results in high luminous efficiency and long lifetime. In particular, it significantly improves the chromatic efficiency ((Cd / A) / CIEy) of blue light devices. Attached Figure Description

[0080] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0081] Figure 1 The hydrogen nuclear magnetic resonance (H-NMR) spectrum of compound 1 provided in the embodiments of the present invention.

[0082] Figure 2 The hydrogen nuclear magnetic resonance (H-NMR) spectrum of compound 2 provided in the embodiments of the present invention.

[0083] Figure 3 This is the emission spectrum of the device in Example 1 of the present invention. Detailed Implementation

[0084] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0085] Example 1: Preparation of compounds 1 and 2

[0086] The synthetic routes for compounds 1 and 2 are as follows:

[0087]

[0088] (1) Synthesis of intermediate 1-I

[0089] Under nitrogen protection, 2-bromo-3-(2-bromophenyl)naphthalene (100 mmol, 36.20 g, CAS: 2350272-28-3, molecular formula C 16 H 10 Br2 (molecular weight 362 g / mol) was dissolved in 400 mL of tetrahydrofuran under nitrogen protection. The solution was cooled to -78 °C, and 88 mL of a tetrahydrofuran solution of n-butyllithium (concentration 2.5 mol / L, n-butyllithium amount 220 mmol, n-butyllithium molecular weight 64) was slowly added dropwise while stirring for 1 hour. Then, 8.7 mL of phosphorus trichloride (100 mmol, PCl3 molecular weight 137, density 1.574 g / cm³) was slowly added dropwise. 3 After the reaction solution was brought to room temperature, it was refluxed for 1 hour. The solid was filtered off under nitrogen, and the filtrate was concentrated under reduced pressure. 14.21 g of product was obtained (yield 53.0%, molecular formula C). 16 H 10 ClP (molecular weight 268). Dissolve it in 50 ml of tetrahydrofuran for later use.

[0090] (2) Synthesis of intermediate 1-II (introduction of NO2)

[0091] Under a nitrogen stream, 13.34 g (53.0 mmol, molecular weight 252, C10) of 2-bromo-3-nitronaphthalene was added. 10 H6BrNO2 (CAS: 67116-33-0) was dissolved in 100 mL of tetrahydrofuran under nitrogen protection and stirred at -78 °C for 0.5 h. Then, 50 mL of a tetrahydrofuran solution of n-butyllithium (2.5 mol / L) was slowly added dropwise, and the mixture was stirred for 1 h. Next, a tetrahydrofuran solution of intermediate 1-I obtained from the first step was slowly added dropwise. After reacting for 2 h, the reaction solution was brought to room temperature and stirred overnight. Water was added to the reaction solution and stirred for 30 min. The mixture was allowed to stand and separated. The filtrate was extracted with ethyl acetate, and the organic layers were combined and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography.

[0092] The solid obtained above was dissolved in 80 mL of ethyl acetate and cooled to 0 °C. 10 mL of a 35% hydrogen peroxide aqueous solution was slowly added dropwise. The reaction solution was cooled to room temperature and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography to give 10.05 g (23.87 mmol, yield 45.0%) of intermediate 1-II (C 26 H 16 NO3P (molecular weight 421).

[0093] (3) Synthesis of intermediate 1-III (NH2ization)

[0094] 10.05 g (23.87 mmol) of intermediate 1-II, 1.0 g of Pd / C catalyst with 10% palladium content, and 200 mL of ethanol were added to a high-pressure reactor, which was then purged with hydrogen (3 MPa) and heated to 50 °C with stirring for 3 hours. The solid was filtered off after cooling, and the filtrate was concentrated under reduced pressure. The crude product obtained was purified by silica gel column chromatography to give 8.52 g (21.79 mmol, yield: 91.3%) of intermediate 1-III. (C) 26 H 18 NOP (molecular weight 391)

[0095] (4) Synthesis of Compound 1 and Compound 2 (ring sealing)

[0096] 8.52 g (21.79 mmol) of intermediate 1-III was dissolved in 100 ml of a sulfuric acid / acetic acid mixture while adding sodium nitrite, keeping the temperature below 10 °C. After adding 2 g of sodium nitrite, the mixture was gradually brought to room temperature and stirred for 10 hours at room temperature. The reaction solution was neutralized with sodium carbonate, extracted with toluene and ethyl acetate, and the organic layer was washed once with water, dried with anhydrous sodium sulfate, and concentrated to obtain the crude product. The crude product was purified by preparative GPC, and then toluene was added in multiple batches to dissolve the crude product under slight heating. After complete dissolution, ethanol was added, and a precipitate formed. The precipitate and filtrate were filtered separately, dried, and the dissolution / precipitation process was repeated. The solubility difference between compounds 1 and 2 due to their molecular symmetry was used for purification. Finally, 0.92 g of compound 1 (yield 11.3%) and 1.34 g of c-1 (yield 16.4%) were obtained (C... 26 H 15 OP, molecular weight 374).

[0097] The structure of the compound was confirmed by nuclear magnetic resonance. The spectrum of compound 1 is shown below. Figure 1 The spectrum of compound 2 is shown below. Figure 2 It can be noted that, due to limitations in the purification process, trace amounts of characteristic peaks of compound 2 remain in the spectrum of compound 1. Similarly, a small amount of compound 1 is also present in compound 2. Sublimation is used to purify the raw materials to meet the purity requirements for device fabrication.

[0098] Example 2 Preparation of compounds 3 and 4

[0099] The synthetic routes for compounds 3 and 4 are as follows:

[0100]

[0101] (1) Synthesis of intermediate 2-I

[0102] Under nitrogen protection, 2-bromo-1-(2-bromophenyl)naphthalene (100 mmol, 36.21 g, CAS: 92866-09-6, molecular formula C 16 H 10 Br2 (molecular weight 362 g / mol) was dissolved in 400 mL of tetrahydrofuran under nitrogen protection. The solution was cooled to -78 °C, and 88 mL of a tetrahydrofuran solution of n-butyllithium (concentration 2.5 mol / L, n-butyllithium amount 220 mmol, n-butyllithium molecular weight 64) was slowly added dropwise while stirring for 1 hour. Then, 8.7 mL of phosphorus trichloride (100 mmol, PCl3 molecular weight 137, density 1.574 g / cm³) was slowly added dropwise. 3 After the reaction solution was brought to room temperature, it was heated under reflux for 1 hour. The solid was filtered off under nitrogen, and the filtrate was concentrated under reduced pressure. 13.75 g of product was obtained (yield 51.3%, molecular formula C). 16 H 10 ClP (molecular weight 268). Dissolve it in 50 ml of tetrahydrofuran for later use.

[0103] (2) Synthesis of intermediate 2-II (introduction of NO2)

[0104] Under a nitrogen stream, 12.93 g (51.3 mmol, molecular weight 252, C10) of 2-bromo-1-nitronaphthalene was... 10 H6BrNO2 (CAS: 4185-62-0) was dissolved in 100 mL of tetrahydrofuran under nitrogen protection and stirred at -78 °C for 0.5 h. Then, 40 mL of a tetrahydrofuran solution of n-butyllithium (2.5 mol / L) was slowly added dropwise, and the mixture was stirred for 1 h. Next, a tetrahydrofuran solution of intermediate 2-I obtained in the first step was slowly added dropwise. After reacting for 2 h, the reaction solution was brought to room temperature and stirred overnight. Water was added to the reaction solution and stirred for 30 min. The mixture was allowed to stand and separated. The filtrate was extracted with ethyl acetate, and the organic layers were combined and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography.

[0105] The solid obtained above was dissolved in 80 mL of ethyl acetate and cooled to 0 °C. 10 mL of a 35% hydrogen peroxide aqueous solution was slowly added dropwise. The reaction solution was cooled to room temperature and concentrated under reduced pressure. The crude product obtained was purified by silica gel column chromatography to give 10.55 g (25.06 mmol, yield 48.8%) of intermediate 2-II (C 26 H 16 NO3P (molecular weight 421).

[0106] (3) Synthesis of intermediate 2-III (NH2ization)

[0107] 10.55 g (25.06 mmol) of intermediate 2-II, 1.0 g of Pd / C catalyst with 10% palladium content, and 200 mL of ethanol were added to a high-pressure reactor, which was then purged with hydrogen (3 MPa) and heated to 50 °C with stirring for 3 hours. The solid was filtered off after cooling, and the filtrate was concentrated under reduced pressure. The crude product obtained was purified by silica gel column chromatography to give 8.87 g (22.68 mmol, yield: 90.5%) of intermediate 2-III. (C) 26 H 18 NOP (molecular weight 391)

[0108] (4) Synthesis of compounds 3 and 4 (ring sealing)

[0109] 8.87 g (22.68 mmol) of intermediate 2-III was dissolved in 100 ml of a sulfuric acid / acetic acid mixture while adding sodium nitrite, keeping the temperature below 10 °C. After adding 2 g of sodium nitrite, the mixture was gradually brought to room temperature and stirred for 10 hours at room temperature. The reaction solution was neutralized with sodium carbonate, extracted with toluene and ethyl acetate, and the organic layer was washed once with water, dried with anhydrous sodium sulfate, and concentrated to obtain the crude product. The crude product was purified by preparative GPC, and then toluene was added in multiple batches to dissolve the crude product under slight heating. After complete dissolution, ethanol was added, and a precipitate formed. The precipitate and filtrate were filtered separately, dried, and the dissolution / precipitation process was repeated. The solubility difference between compounds 3 and 4 due to their molecular symmetry was used for purification. Finally, 1.00 g of compound 3 (yield 11.8%) and 1.33 g of d-1 (yield 15.7%) were obtained (C). 26 H 15 OP, molecular weight 374).

[0110] The structure of the compound was confirmed by nuclear magnetic resonance.

[0111] Example 3 Preparation of Compound 5

[0112]

[0113] (1) Synthesis of intermediate 5-I

[0114] Under nitrogen protection, 1-bromo-2-(2-bromophenyl)naphthalene (100 mmol, 36.20 g, CAS: 2247086-41-3, molecular formula C 16 H 10Br2 (molecular weight 362 g / mol) was dissolved in 400 mL of tetrahydrofuran under nitrogen protection. The solution was cooled to -78 °C, and 88 mL of a tetrahydrofuran solution of n-butyllithium (concentration 2.5 mol / L, n-butyllithium amount 220 mmol, n-butyllithium molecular weight 64) was slowly added dropwise while stirring for 1 hour. Then, 8.7 mL of phosphorus trichloride (100 mmol, PCl3 molecular weight 137, density 1.574 g / cm³) was slowly added dropwise. 3 After the reaction solution was brought to room temperature, it was heated under reflux for 1 hour. The solid was filtered off under nitrogen, and the filtrate was concentrated under reduced pressure. 13.29 g of product was obtained (yield 49.6%, molecular formula C). 16 H 10 ClP (molecular weight 268). Dissolve it in 50 ml of tetrahydrofuran for later use.

[0115] (2) Synthesis of intermediate 5-II (introduction of NO2)

[0116] Under a nitrogen atmosphere, 12.50 g of 1-bromo-2-nitronaphthalene (49.6 mmol, molecular weight 252, C10H6BrNO2, CAS: 4182-55-1) was dissolved in 100 mL of tetrahydrofuran. The mixture was stirred at -78 °C for 0.5 h under nitrogen protection. Then, 40 mL of a tetrahydrofuran solution of n-butyllithium (2.5 mol / L) was slowly added dropwise, and the mixture was stirred for 1 h. Next, a tetrahydrofuran solution of the intermediate c-1-I obtained in the first step was slowly added dropwise. After reacting for 2 h, the reaction solution was brought to room temperature and stirred overnight. Water was added to the reaction solution and stirred for 30 min. The mixture was allowed to stand and separated. The filtrate was extracted with ethyl acetate, and the organic layers were combined and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography.

[0117] The solid obtained above was dissolved in 80 mL of ethyl acetate and cooled to 0 °C. 10 mL of a 35% hydrogen peroxide aqueous solution was slowly added dropwise. The reaction solution was cooled to room temperature and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography to give 8.96 g (21.28 mmol, yield 42.9%) of intermediate 5-II (C 26 H 16 NO3P (molecular weight 421).

[0118] (3) Synthesis of intermediate 5-III (NH2ization)

[0119] 8.96 g (21.28 mmol) of intermediate 5-II, 1.0 g of Pd / C catalyst with 10% palladium content, and 200 mL of ethanol were added to a high-pressure reactor, which was then purged with hydrogen (3 MPa) and heated to 50 °C with stirring for 3 hours. The solid was filtered off after cooling, and the filtrate was concentrated under reduced pressure. The crude product obtained was purified by silica gel column chromatography to give 7.56 g (19.34 mmol, yield: 90.9%) of intermediate 5-III. (C) 26 H 18 NOP (molecular weight 391)

[0120] (4) Synthesis of Compound 5 (ring sealing)

[0121] 7.56 g (19.34 mmol) of intermediate 5-III was dissolved in 100 ml of a sulfuric acid / acetic acid mixture while adding sodium nitrite, keeping the temperature below 10 °C. After adding 2 g of sodium nitrite, the mixture was gradually brought to room temperature and stirred for 10 hours at room temperature. The reaction solution was neutralized with sodium carbonate, extracted with toluene and ethyl acetate, and the organic layer was washed once with water, dried with anhydrous sodium sulfate, and concentrated to obtain the crude product. The crude product was purified by preparative GPC, and then toluene was added in multiple batches to dissolve the crude product under slight heating. After complete dissolution, ethanol was added, and a precipitate formed. The precipitate and filtrate were obtained by filtration, and the precipitate was dried. The dissolution / precipitation process was repeated. Finally, 0.75 g (2.01 mmol, yield 10.4%) of compound 5 of the present invention was obtained (C 26 H 15 OP, molecular weight 374).

[0122] The structure of the compound was confirmed by nuclear magnetic resonance.

[0123] Example 4 Preparation of Compound 6

[0124]

[0125] (1) Synthesis of intermediate 6-I

[0126] Using tetrahydrofuran as a solvent, 1,4-dibromo-2-iodobenzene (89284-52-6) and 2-bromo-3-iodonaphthalene are coupled using Grignard reagents (such as bromo(1-methylethyl)magnesium prepared on-site) to generate the raw material 2-bromo-3-(2,5-dibromophenyl)naphthalene.

[0127] Under nitrogen protection, 2-bromo-3-(2,5-dibromophenyl)naphthalene (100 mmol, 44.00 g, molecular formula C 16H9Br3 (molecular weight 440 g / mol) was dissolved in 400 mL of tetrahydrofuran under nitrogen protection. The solution was cooled to -78 °C, and 88 mL of a tetrahydrofuran solution of n-butyllithium (concentration 2.5 mol / L, n-butyllithium amount 220 mmol, n-butyllithium molecular weight 64) was slowly added dropwise while stirring for 1 hour. Then, 8.7 mL of phosphorus trichloride (100 mmol, PCl3 molecular weight 137, density 1.574 g / cm³) was slowly added dropwise. 3 After the reaction solution was brought to room temperature, it was refluxed for 1 hour. The solid was filtered off under nitrogen, and the filtrate was concentrated under reduced pressure. The crude product was purified by silica gel column chromatography, yielding 14.18 g of product (yield 40.8%, molecular formula C). 16 H9BrClP (molecular weight 347.5). Dissolve it in 50 ml of tetrahydrofuran for later use.

[0128] (2) Synthesis of intermediate 6-II (introduction of NO2)

[0129] Under a nitrogen stream, 10.28 g (40.8 mmol, molecular weight 252, C10) of 2-bromo-3-nitronaphthalene was subjected to nitrogen treatment. 10 H6BrNO2 (CAS: 67116-33-0) was dissolved in 100 mL of tetrahydrofuran under nitrogen protection and stirred at -78 °C for 0.5 h. Then, 30 mL of a tetrahydrofuran solution of n-butyllithium (2.5 mol / L) was slowly added dropwise, and the mixture was stirred for 1 h. Next, a tetrahydrofuran solution of the intermediate 6-I obtained in the first step was slowly added dropwise. After reacting for 2 h, the reaction solution was brought to room temperature and stirred overnight. Water was added to the reaction solution and stirred for 30 min. The mixture was allowed to stand and separated. The filtrate was extracted with ethyl acetate, and the organic layers were combined and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography.

[0130] The solid obtained above was dissolved in 80 mL of ethyl acetate and cooled to 0 °C. 10 mL of a 35% hydrogen peroxide aqueous solution was slowly added dropwise. The reaction solution was cooled to room temperature and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography to give 9.02 g (18.03 mmol, yield 44.2%) of intermediate 6-II (C 26 H 15 BrNO3P (molecular weight 500).

[0131] (3) Synthesis of intermediate 6-III (NH2ization)

[0132] 9.02 g (18.03 mmol) of intermediate 6-II, 1.0 g of Pd / C catalyst with 10% palladium content, and 200 mL of ethanol were added to a high-pressure reactor, which was then purged with hydrogen (3 MPa) and heated to 50 °C with stirring for 3 hours. The solid was filtered off after cooling, and the filtrate was concentrated under reduced pressure. The crude product obtained was purified by silica gel column chromatography to give 7.92 g (16.89 mmol, yield: 93.7%) of intermediate 6-III. (C) 26 H 17 BrNOP (molecular weight 469)

[0133] (4) Synthesis of intermediate 6-IV (ring sealing)

[0134] 7.92 g (16.89 mmol) of intermediate 6-III was dissolved in 100 mL of a sulfuric acid / acetic acid mixture while adding sodium nitrite, keeping the temperature below 10 °C. After adding 2 g of sodium nitrite, the mixture was gradually brought to room temperature and stirred for 10 hours at room temperature. The reaction solution was neutralized with sodium carbonate, extracted with toluene and ethyl acetate, and the organic layer was washed once with water, dried with anhydrous sodium sulfate, and concentrated to obtain the crude product. The crude product was purified using preparative GPC, and then toluene was added in multiple batches to dissolve the crude product under slight heating. After complete dissolution, ethanol was added, resulting in precipitation. The precipitate and filtrate were obtained by filtration, dried separately, and the dissolution / precipitation process was repeated. The products were purified separately by utilizing the difference in solubility due to molecular symmetry. A total of 0.83 g (1.83 mmol, yield 10.8%) of intermediate 6-IV (C26H14BrOP, molecular weight 453) was obtained.

[0135] (5) Introducing a triarylamine group (ring sealing)

[0136] Intermediate 6-IV (1.83 mmol) and starting material diphenylamine (1.83 mmol) were dissolved in 50.00 mL of toluene solution. Tris(dibenzylacetone)dipalladium (0.09 mmol), tri-tert-butylphosphine (0.43 mmol), and sodium tert-butoxide (17.29 mmol) were added, and the mixture was stirred until homogeneous. The mixture was heated to 95 °C and refluxed for 5 h. After the reaction was completed, the temperature was slightly lowered, and the mixture was filtered through diatomaceous earth to remove salts and catalysts. The filtrate was cooled to room temperature and washed three times with water, retaining the organic phase. The aqueous phase was then extracted with ethyl acetate. The combined organic phases were dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The remaining substances were purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V = 10:4) to obtain 0.87 g of compound 6 (1.61 mmol, yield: 87.88%, Mw: 541).

[0137] The structure of the compound was confirmed by nuclear magnetic resonance.

[0138] Example 5 Preparation of Compound 46

[0139]

[0140] Synthesis of intermediate 46-IV:

[0141] (1) The raw material 2-bromo-3-(2-bromophenyl)naphthalene in step (1) of Synthesis Example 1 was replaced with 1-bromo-2-(2-bromophenyl)-3-iodonaphthalene, and the raw material 2-bromo-3-nitronaphthalene in step (2) was replaced with 1-bromo-3-iodo-2-nitronaphthalene. Based on the same reaction mechanism, intermediate 46-IV was prepared with a weight of 1.54 g (2.89 mmol, molecular weight 532).

[0142] Synthesis of Compound 46

[0143] (2) Under nitrogen protection, intermediate 46-IV (2.89 mmol) and starting material 4,4'-bis(1-naphthyl)diphenylamine (5.78 mmol) were dissolved in 130.00 ml of toluene solution. Tris(dibenzylacetone)dipalladium (0.04 mmol), tri-tert-butylphosphine (0.19 mmol), and sodium tert-butoxide (7.66 mmol) were added, stirred until homogeneous, heated to 90 °C, and refluxed for 5 h. After the reaction was completed, the temperature was slightly lowered to 75 °C, and diatomaceous earth was used. The solution was filtered to remove salt and catalyst. After cooling the filtrate to room temperature, it was washed three times with water, and the organic phase was retained. The aqueous phase was then extracted with ethyl acetate. The organic phases were combined and dried with anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The remaining substance was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (dichloromethane: petroleum ether volume ratio = 10:4) to obtain 3.06 g (2.52 mmol, yield: 87.3%, molecular weight: 1213) of compound 46.

[0144] The structure of the compound was confirmed by nuclear magnetic resonance (NMR). The NMR spectrum is omitted.

[0145] Example 6 Preparation of Compound 47

[0146]

[0147] (1) Synthesis of intermediates 47-1 and 47-2

[0148] Under nitrogen protection, starting materials 47-A (200 mmol) and 47-B (200 mmol) were dissolved in toluene solution. Tris(dibenzylacetone)dipalladium (2 mmol), tri-tert-butylphosphine (10 mmol), and sodium tert-butoxide (400 mmol) were added, stirred until homogeneous, heated to 90 °C, and refluxed for 5 hours. After the reaction was completed, the temperature was slightly lowered to 75 °C, and the mixture was filtered through diatomaceous earth to remove salts and catalysts. The filtrate was cooled to room temperature, washed three times with water, and the organic phase was retained. The aqueous phase was then extracted with ethyl acetate. The combined organic phases were dried with anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator to obtain a solid organic compound. The solid organic compound was completely dissolved in dichloromethane and then slowly added dropwise to a petroleum ether solution. After stirring until homogeneous, a precipitate formed. The precipitate was filtered to obtain a solid, which was washed successively with anhydrous ethanol and petroleum ether, and dried to prepare intermediate 47-1.

[0149] Using the Suzuki-Miyaura reaction mechanism again, with the same catalyst and reaction conditions, intermediate 47-1 (100 mmol) and starting material 47-C underwent a coupling reaction to prepare intermediate 47-2. 92.34 g (151.38 mmol, molecular weight 610) was obtained.

[0150] (2) Synthesis of intermediate 47-3

[0151] Under nitrogen protection, intermediate 47-2 (100 mmol, 61.00 g) was dissolved in 600 mL of tetrahydrofuran. The solution was cooled to -78 °C, and 88 mL of a tetrahydrofuran solution of n-butyllithium (2.5 mol / L, 220 mmol n-butyllithium, molecular weight 64) was slowly added dropwise while stirring for 1 hour. Then, 8.7 mL of phosphorus trichloride (100 mmol, PCl3 molecular weight 137, density 1.574 g / cm³) was slowly added dropwise. 3 After the reaction solution was brought to room temperature, it was heated under reflux for 1 hour. The solid was filtered off under nitrogen, and the filtrate was concentrated under reduced pressure. The intermediate 47-3 was obtained in a weight of 30.24 g (yield 53.8%, molecular formula C). 38 H 25 ClNP (molecular weight 562). Dissolve it in 80 ml of tetrahydrofuran for later use.

[0152] (3) Synthesis of intermediate 47-4 (introduction of NO2)

[0153] Under nitrogen protection, 13.56 g (53.8 mmol, molecular weight 252, C10) of 2-bromo-3-nitronaphthalene was... 10H6BrNO2 (CAS: 67116-33-0) was dissolved in 100 mL of tetrahydrofuran under nitrogen protection and stirred at -78 °C for 0.5 h. Then, 50 mL of a tetrahydrofuran solution of n-butyllithium (2.5 mol / L) was slowly added dropwise, and the mixture was stirred for 1 h. Next, a tetrahydrofuran solution of intermediate 47-4 obtained in the first step was slowly added dropwise. After reacting for 2 h, the reaction solution was brought to room temperature and stirred overnight. Water was added to the reaction solution and stirred for 30 min. The mixture was allowed to stand and separated. The filtrate was extracted with ethyl acetate, and the organic layers were combined and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography.

[0154] The solid obtained above was dissolved in 80 ml of ethyl acetate and cooled to 0 °C. 10 ml of a 35% hydrogen peroxide aqueous solution was slowly added dropwise. The reaction solution was cooled to room temperature and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography to give 17.98 g (25.18 mmol, yield 46.8%) of intermediate 47-4 (C48H31N2O3P, molecular weight 714).

[0155] (4) Synthesis of intermediate 47-5 (NH2ization)

[0156] 17.98 g (25.18 mmol) of intermediate 47-4, 1.0 g of Pd / C catalyst with 10% palladium content, and 200 mL of ethanol were added to a high-pressure reactor, which was then purged with hydrogen (3 MPa) and heated to 50 °C with stirring for 3 hours. The mixture was cooled and the solid was filtered off. The filtrate was concentrated under reduced pressure. The crude product obtained was purified by silica gel column chromatography to give 15.95 g (23.32 mmol, yield: 92.6%) of intermediate 47-5 (C48H33N2OP, molecular weight 684).

[0157] (5) Synthesis of compound 47 (ring-sealing)

[0158] 15.95 g (23.32 mmol) of intermediate 47-5 was dissolved in 100 ml of a sulfuric acid / acetic acid mixture while adding sodium nitrite, keeping the temperature below 10 °C. After adding 2 g of sodium nitrite, the mixture was gradually brought to room temperature and stirred at room temperature for 10 hours. The reaction solution was neutralized with sodium carbonate, extracted with toluene and ethyl acetate, and the organic layer was washed once with water, dried with anhydrous sodium sulfate, and concentrated to obtain the crude product. The crude product was purified by preparative GPC, and then toluene was added in multiple batches to dissolve the crude product under slight heating. After complete dissolution, ethanol was added, and a precipitate formed. The precipitate and filtrate were filtered separately, dried, and the dissolution / precipitation process was repeated for purification. Finally, 2.41 g (3.61 mmol, yield 15.5%) of compound 47 of the present invention was obtained (C). 48 H 30 NOP (molecular weight 667).

[0159] The structure of the compound was confirmed by nuclear magnetic resonance.

[0160] Example 7

[0161] Compounds 7-45 and 48-51 were synthesized according to the preparation methods described in Examples 1-6. The structures of the compounds were confirmed by nuclear magnetic resonance.

[0162] Device Application Example 1

[0163] This application example provides a method for fabricating an organic electroluminescent device, comprising the following steps:

[0164] The ITO / Ag / ITO thin film (ITO thickness 14nm, Ag thickness 150nm) on the OLED device glass substrate (150nm) was washed twice with distilled water, ultrasonically cleaned for 30 minutes, repeatedly washed twice with distilled water, and ultrasonically cleaned for 10 minutes. After the distilled water cleaning, it was ultrasonically cleaned in sequence with solvents such as isopropanol, acetone, and methanol, then dried, transferred to a plasma cleaner, cleaned for 5 minutes, and then sent to an evaporation deposition machine. Using this substrate as the anode, the device deposition process was performed using the evaporation deposition machine, and other functional layers were sequentially deposited on it.

[0165] Compound HT and P-dopant (3%) were introduced into a chamber of a vacuum vapor deposition apparatus, and the pressure in the chamber was then controlled to 10⁻⁶ Torr. Subsequently, an electric current was applied to the chamber to evaporate the introduced material, thereby forming a hole injection layer with a thickness of 10 nm on an ITO substrate. Next, compound HT was introduced into another chamber of the vacuum vapor deposition apparatus, and the compound was evaporated by applying an electric current to the chamber, thereby forming a hole transport layer with a thickness of 130 nm on the hole injection layer.

[0166] The compound prime was then introduced into a chamber of a vacuum vapor deposition apparatus, and the compound was evaporated by applying an electric current to the chamber, thereby forming a light-emitting auxiliary layer with a thickness of 10 nm on the hole transport layer. The compound host was introduced into one chamber of the vacuum vapor deposition apparatus as a host, and the compound 1 of the present invention was introduced into another chamber as a dopant. The doping ratio of the host material to the dopant material was 97:3, forming a light-emitting layer with a thickness of 20 nm on the light-emitting auxiliary layer.

[0167] ET and Liq were simultaneously vacuum-deposited on the aforementioned light-emitting layer as electron transport layers (35 nm, 50%); Yb with a thickness of 1.0 nm was vacuum-deposited on the aforementioned electron transport layer as an electron injection layer. Magnesium and silver were vacuum-deposited on the electron injection layer as cathodes, with a magnesium to silver weight ratio of 1:9 and a deposition thickness of 18 nm. A CPL layer with a deposition thickness of 70 nm was then vacuum-deposited on the aforementioned cathode, thus obtaining an organic electroluminescent device.

[0168] Device structure:

[0169] ITO / Ag / ITO / HT:P-dopant(10nm, 3%) / HT(130nm) / prime(10nm) / Host:Dopant(Compound 1 of this invention)(20nm, 2%) / ET:Liq(35nm, 50%) / Yb(1nm) / Mg:Ag(18nm, 1:9) / CPL(70nm).

[0170]

[0171] Device Application Example 2-15

[0172] OLED devices were prepared by using compounds 2, 3, 4, 5, 6, 7, 10, 19, 25, 29, 34, 44, 46, and 47 of the present invention as doping materials for the light-emitting layer, replacing compound 1, and following the same method and conditions as described above.

[0173] Device Comparison Example 1:

[0174] OLED devices were fabricated using the boron nitride compound BD-1 as the dopant material for the light-emitting layer, replacing compound 1, and following the same method and conditions as described above.

[0175]

[0176] Device performance

[0177] The driving voltage, luminous efficiency, BI value, and lifetime of the organic electroluminescent devices obtained from the above-mentioned device embodiments and comparative devices were characterized at a brightness of 1000 nits. The test results are shown in Table 1 below:

[0178] Table 1:

[0179]

[0180] As shown in Table 1, the organic electroluminescent devices formed by the compounds provided in the embodiments of the present invention exhibit improved performance in terms of BI value and lifetime compared to the comparative compound BD-1. Since the driving voltage is mainly affected by the host material, a reduction of 0.1-0.3 in the driving voltage is already considered a significant improvement when only the doping material is changed and the host material remains unchanged.

[0181] The emission spectra of devices 1-15 were measured using a PR670 spectrometer. The measured emission peak max was found to be at 458 nm, with a full width at half maximum (FWHM) of 18 nm. (See attached image.) Figure 3 This is the spectrum of device application example 1. As can be seen from the emission peak and full width at half maximum (FWHM), the device of this invention has the advantages of narrow spectrum and high color purity. The PR670 spectrometer has a measurement accuracy of 2 nm.

[0182] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0183] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A phosphorus-containing polycyclic luminescent compound, characterized in that, Its general structural formula is shown in Formula I: ； m and n are each independently selected from integers between 0 and 4; p is selected from integers between 0 and 3; La, Lb, and Lc are each independently selected from the linking bond, phenylene, biphenylene, or naphthylene; Ar1-Ar6 are each independently selected from the following structures: 。 2. The phosphorus-containing polycyclic luminescent compound according to claim 1, characterized in that, Formula I includes the following general structural formula: 。 3. A method for preparing a phosphorus-containing polycyclic luminescent compound as described in claim 1 or 2, characterized in that, The synthesis route is as follows: ； In the above formulas, the rings AC, m, n, p, La, Lb, Lc, and Ar1-Ar6 are represented in the same way as in Formula I; where X represents a halogen. Specific preparation methods include: Step 1: Preparation of Intermediate 1 Under nitrogen protection, raw material a was dissolved in tetrahydrofuran. The solution was cooled to -78°C, and a tetrahydrofuran solution of n-butyllithium was added dropwise. After stirring for 1-5 hours, phosphorus trichloride was added dropwise. The reaction solution was restored to room temperature and heated under reflux for 1-5 hours. After filtration and vacuum concentration, intermediate 1 was obtained and dissolved in tetrahydrofuran for later use. Step 2, Preparation of Intermediate 2 Under nitrogen protection, raw material b was dissolved in tetrahydrofuran and stirred at -78°C for 0.5-5 hours. Then, a tetrahydrofuran solution of n-butyllithium was added dropwise and stirred for 1-5 hours. Next, a tetrahydrofuran solution of intermediate 1 obtained in step 1 was added dropwise and reacted for 1-5 hours. The reaction solution was then brought back to room temperature and stirred overnight. Water was added to the reaction solution and stirred for 10-50 minutes. The mixture was allowed to stand and separated. After extraction, the organic layers were combined, concentrated under reduced pressure, and purified. The resulting solid was dissolved in ethyl acetate and cooled to 0°C. Hydrogen peroxide aqueous solution was added dropwise, and the reaction solution was cooled to room temperature and concentrated under reduced pressure. Finally, after purification, intermediate 2 was obtained. Step 3, Preparation of Intermediate 3 Intermediate 2, Pd / C catalyst and ethanol were added to a high-pressure reactor, hydrogen was introduced, and the mixture was heated and stirred for 1-10 hours. The solid was filtered off after cooling, and the filtrate was concentrated under reduced pressure and purified to obtain intermediate 3. Step 4, Preparation of Intermediate 4 Intermediate 3 was dissolved in a sulfuric acid / acetic acid mixed solution. Sodium nitrite was added while keeping the temperature below 10°C. The temperature was then restored to room temperature and stirred at room temperature for 5-24 hours. The reaction solution was neutralized, extracted, washed, dried and concentrated to obtain a crude product. The crude product was then purified to obtain intermediate 4. Step 5: Preparation of the product Under nitrogen protection, intermediate 4 and raw material e were dissolved in toluene solution, and tris(dibenzylacetone)dipalladium, tri-tert-butylphosphine and sodium tert-butoxide were added. The mixture was stirred until homogeneous, heated to 90°C, and refluxed for 1-10 hours. After the reaction was completed, the temperature was lowered to 60-80°C, and the mixture was filtered with diatomaceous earth to remove salt and catalyst. The filtrate was cooled to room temperature, washed three times with water, and the organic phase was retained. The aqueous phase was then extracted and the organic phases were combined. The mixture was dried and the solvent was removed by evaporation. Finally, the remaining substances were purified to obtain the phosphorus-containing polycyclic luminescent compound.

4. A method for preparing a phosphorus-containing polycyclic luminescent compound as described in claim 1 or 2, characterized in that, The synthesis route is as follows: ； In the above formulas, the rings AC, m, n, p, La, Lb, Lc, and Ar1-Ar6 are represented in the same way as in Formula I; where X represents a halogen. Specific preparation methods include: Step 1: Preparation of Intermediate II-1 and Intermediate II-2 Under nitrogen protection, raw material c and raw material d were independently dissolved in toluene solution, and then raw material e with the target structure was added accordingly. Palladium catalyst, phosphine ligand and sodium tert-butoxide were added to each, stirred evenly, heated and refluxed to prepare intermediate II-1 and intermediate II-2. Step 2, Preparation of Intermediate II-3 Under nitrogen protection, intermediate II-1 was dissolved in tetrahydrofuran, and a tetrahydrofuran solution of n-butyllithium was added dropwise. The mixture was stirred until homogeneous, and then phosphorus trichloride was added dropwise. After the reaction solution was brought back to room temperature, it was heated under reflux for 1 hour. The solid was filtered off under nitrogen, and the filtrate was concentrated under reduced pressure to obtain intermediate II-3, which was dissolved in tetrahydrofuran for later use. Step 3: Preparation of Intermediate II-4 Under nitrogen protection, intermediate II-2 was dissolved in tetrahydrofuran, and then a tetrahydrofuran solution of n-butyllithium was added dropwise. The mixture was stirred for 1-5 hours, and then a tetrahydrofuran solution of intermediate II-3 obtained in step 2 was added dropwise. After reacting for 1-5 hours, the reaction solution was brought back to room temperature and stirred overnight. Water was added to the reaction solution and stirred for 10-60 minutes. The mixture was allowed to stand and separated. After extraction, the organic layers were combined and concentrated under reduced pressure. The purified solid was dissolved in ethyl acetate and cooled to 0°C. Hydrogen peroxide aqueous solution was added dropwise, and the reaction solution was cooled to room temperature and concentrated under reduced pressure. Finally, the crude product of intermediate II-4 was obtained after purification. Step 4: Synthesis of Intermediate II-5 Intermediate II-4, Pd / C catalyst and ethanol were added to a high-pressure reactor, hydrogen was introduced, and the mixture was heated and stirred for 1-10 hours. The solid was filtered off after cooling, and the filtrate was concentrated under reduced pressure and purified to obtain intermediate II-5. Step 5: Synthesis of the final product Intermediate II-5 was dissolved in a sulfuric acid / acetic acid mixed solution. Sodium nitrite was added while maintaining the temperature below 10°C. After adding sodium nitrite, the solution was restored to room temperature and stirred at room temperature for 5-24 hours. The reaction solution was neutralized, extracted, washed, dried, and concentrated to obtain a crude product. The crude product was then purified to obtain the phosphorus-containing polycyclic luminescent compound.

5. An organic electroluminescent device, comprising an organic layer, characterized in that, The organic layer includes a light-emitting layer; The light-emitting layer comprises a host material and a dopant material, wherein the dopant material comprises the phosphorus-containing polycyclic luminescent compound as described in claim 1 or 2.

6. An organic electroluminescent device according to claim 5, characterized in that, The mass ratio of the main material to the doped material is (90-99.5):(0.5-10).

7. The application of an organic electroluminescent device as described in claim 5 or 6 in the fabrication of organic light-emitting devices, organic solar cells, electronic paper, organic photoreceptors, or organic thin-film transistors.

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