An organic electroluminescent material and an organic electroluminescent device comprising the same

Abstract

The application belongs to the field of organic photoelectric materials, and discloses an organic electroluminescent material and an organic electroluminescent device containing the same. The structure of the organic electroluminescent material is shown in formula I. The organic electroluminescent material provided by the application can not only reduce the driving voltage of the device, but also improve the maximum external quantum efficiency of the device and prolong the phosphorescent lifetime of the device when the organic electroluminescent material is used as the material in a light-emitting layer.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of organic optoelectronic materials, and particularly relates to an organic electroluminescent material and an organic electroluminescent device comprising the same. BACKGROUND

[0002] An organic electroluminescent device (OLED) is a device that changes electric energy into light by applying electricity to an organic electroluminescent material, and generally has a structure comprising an anode, a cathode, and an organic layer between the anode and the cathode. The organic layer of the organic EL device can be composed of a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer (which comprises a host material and a dopant material), an electron buffer layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc., and the materials used for the organic layer are classified by their functions as a hole injection material, a hole transport material, an electron blocking material, a light-emitting material, an electron buffer material, a hole blocking material, an electron transport material, an electron injection material, etc. In the organic EL device, due to the applied voltage, holes are injected from the anode into the light-emitting layer, and electrons are injected from the cathode into the light-emitting layer, and high-energy excitons are formed by the recombination of holes and electrons. By this energy, the organic light-emitting compound reaches an excited state, and light is emitted by the energy generated by the return of the organic light-emitting compound from the excited state to the ground state, thereby producing luminescence.

[0003] However, the existing organic electroluminescent material has low stability, poor matching of HOMO, LUMO energy level and adjacent energy level, resulting in unbalanced carrier mobility, and thus causing the problems of high driving voltage, low luminous efficiency, and short service life of the organic electroluminescent device comprising the organic electroluminescent material, which seriously limits the application of the organic electroluminescent device. Therefore, how to develop a high-performance light-emitting material that makes the organic electroluminescent device have comprehensive characteristics such as high efficiency, long service life, and low voltage is a technical problem that needs to be solved by the person skilled in the art. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides an organic electroluminescent material and an organic electroluminescent device comprising the same. The organic electroluminescent material provided by the present application, as a material in the light-emitting layer, not only can reduce the driving voltage of the device, but also can improve the maximum external quantum efficiency of the device and prolong the phosphorescent lifetime of the device.

[0005] In order to achieve the above-mentioned purpose, the following technical solutions are adopted:

[0006] The first object of the present application is to provide an organic electroluminescent material having the structure shown in general formula I: ;

[0007] wherein,

[0008] selected from substituted or unsubstituted C3-C10 nitrogen heterocycle, and the connecting position is N on the nitrogen heterocycle;

[0009] X is independently selected from O, S, Se, NRx, CRxRy, SiRxRy, GeRxRy; wherein, Rxand Ryare selected from hydrogen, methyl, -F, -D, -CN, -CD3, phenyl;

[0010] one of R1, R2, R3and R4is connected with the rest are independently selected from hydrogen, deuterium, halogen, -CN, substituted or unsubstituted C1-C20alkyl, substituted or unsubstituted C3-C20cycloalkyl, substituted or unsubstituted C3-C20heterocyclyl, substituted or unsubstituted C6-C30aryl, substituted or unsubstituted C6-C30heteroaryl, trimethylgermanium, trimethylsilicon and combinations thereof;

[0011] R5, R6, R7, R8and R9are each independently selected from any one or more combinations of hydrogen, -D, -CN, -F, C1-C20alkyl which is fully or partially substituted with deuterium, cyclopentyl, cyclohexyl, substituted or unsubstituted C6-C30aryl, substituted or unsubstituted C6-C30heteroaryl, substituted or unsubstituted C3-C20cycloalkyl;

[0012] R 10 , R 11 , R 12 , R 13 and R 14 are each independently selected from hydrogen, deuterium, halogen, -CN, substituted or unsubstituted C1-C20alkyl, substituted or unsubstituted C3-C20cycloalkyl, substituted or unsubstituted C3-C20heterocyclyl, substituted or unsubstituted C6-C30aryl, substituted or unsubstituted C6-C30heteroaryl, trimethylgermanium, trimethylsilicon and combinations thereof, and two adjacent groups can form a cyclic structure;

[0013] R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 and R 22 are each independently selected from any one or more combinations of hydrogen, -D, -CN, -F, -CF3, C1-C20alkyl which is fully or partially substituted with deuterium, cyclopentyl, cyclohexyl, substituted or unsubstituted C6-C30aryl, substituted or unsubstituted C3-C30heteroaryl, substituted or unsubstituted C3-C20cycloalkyl, trimethylgermanium, trimethylsilicon;

[0014] The hydrogen atom in the above group can be partially or entirely replaced with deuterium.

[0015] Further,

[0016] X is independently selected from O, S, Se, NRx, CRxRy, SiRxRy, GeRxRy; wherein Rxand Ryare selected from hydrogen, methyl;

[0017] selected from substituted or unsubstituted piperidinyl, substituted or unsubstituted pyrrolidinyl;

[0018] at least one of R1, R2, R3and R4is not hydrogen, each independently selected from hydrogen, -F, -CD3, -CN, phenyl, methyl, ethyl, propyl, butyl, pentyl;

[0019] R5, R6, R7, R8and R9are each independently selected from hydrogen, -D, -F, -CN, -CD3, substituted or unsubstituted phenyl, substituted or unsubstituted methyl, substituted or unsubstituted ethyl, substituted or unsubstituted propyl, substituted or unsubstituted butyl, substituted or unsubstituted pentyl, substituted or unsubstituted cyclohexyl, and adjacent two groups can form a cyclic structure;

[0020] R 10 , R 11 , R 12 , R 13 and R 14 are each independently selected from hydrogen, -D, -F, -CN, -CD3, substituted or unsubstituted phenyl, methyl, ethyl, propyl, butyl, trimethylgermanium, trimethylsilicon, and adjacent two groups can form a cyclic structure or any one or a combination of at least two of the following groups:

[0021] ;

[0022] The above alkyl, aryl can be partially or entirely replaced with deuterium.

[0023] It should be noted that the above substituted or unsubstituted is substituted with one, two or more substituents selected from the following: deuterium; halogen group; cyano group; C1-C20 alkyl; C3-C20 cycloalkyl; C6-C30 aryl; C3-C20 heterocyclyl, or a substituent connected by two or more substituents of the above-mentioned substituents, or without substituents; and the above is the connection position.

[0024] Further, selected from the following groups:

[0025] .

[0026] Further, the ligand selected from the following structures:

[0027]

[0028] Further, the ligand selected from the following structures:

[0029]

[0030] In the present application, the organic electroluminescent material is selected from any one of the following structures:

[0031]

[0032] ​

[0033] 。

[0034] The above only lists some specific structural forms, but the series of organic electroluminescent materials are not limited to the above molecular structures, and other specific molecular structures can be obtained by simple transformation of some simple groups and their substituted groups and substitution positions, which will not be described one by one here.

[0035] In the present application, the preparation process of the organic electroluminescent material of formula I is as follows:

[0036] ;

[0037] wherein, R1-R 22 , A and X are defined as the same as the foregoing, which will not be described again.

[0038] The preparation operation is as follows:

[0039] Under the protection of nitrogen, the ligand formula V' and IrC13·3H2O are put into the reaction system, a mixed solution of ethylene glycol ethyl ether and pure water is added, and the system is refluxed at 120°C for 36 hours under the protection of nitrogen to obtain the intermediate formula IV;

[0040] Silver trifluoromethanesulfonate is added to the intermediate formula IV, dichloromethane and methanol are further added to the system, and the system is refluxed at 25°C for 48 hours under the protection of nitrogen to obtain the intermediate formula III;

[0041] The ligand formula II is added to the intermediate formula III, anhydrous ethanol is further added to the system, and the system is refluxed at 80°C for 36 hours under the protection of nitrogen to obtain the organic electroluminescent material shown in formula I.

[0042] The second technical object of the present application is to provide an organic electroluminescent device, which comprises an anode, a cathode, and an organic material layer disposed between the anode and the cathode, and the organic material layer comprises the organic electroluminescent material as described above.

[0043] Preferably, the organic material layer comprises a light-emitting layer, and the light-emitting layer comprises a host material and a dopant material, and the dopant material comprises the organic electroluminescent material as described above.

[0044] Preferably, the organic material layer further comprises at least one of a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, an electron transport layer, and an electron injection layer.

[0045] Specifically, the organic electroluminescent device comprises an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a cathode which are sequentially disposed.

[0046] Generally, an organic electroluminescent device includes a first electrode (anode) and a second electrode (cathode), and an organic material layer between the electrodes. The organic material layer can be further divided into a plurality of regions. For example, the organic material layer can include a hole transport region, a light emitting layer, and an electron transport region.

[0047] In specific embodiments, a substrate can be used under the first electrode or over the second electrode. The substrate is a glass or a polymer material having excellent mechanical strength, thermal stability, water resistance, and transparency. In addition, a thin film transistor (TFT) can be provided on the substrate for display.

[0048] The first electrode can be formed by sputtering or depositing a material used for the first electrode on the substrate. When the first electrode is an anode, an oxide transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (Sn02), zinc oxide (ZnO), and any combination thereof can be used. In addition, the anode material can be selected from a material that facilitates hole injection, in addition to the anode materials listed above, and combinations thereof, including known materials suitable for anodes. When the first electrode is a cathode, a metal or an alloy such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag), and any combination thereof can be used. In addition to the cathode materials listed above, the cathode material can be a material that facilitates electron injection, and combinations thereof, including known materials suitable for cathodes.

[0049] The organic material layer can be formed on the electrode by vacuum thermal evaporation, spin coating, printing, or the like. The compound used for the organic material layer can be an organic small molecule, an organic macromolecule, and a polymer, and combinations thereof. The hole transport region is between the anode and the light emitting layer. The hole transport region can be a single layer structure of a hole transport layer (HTL), including a single layer hole transport layer containing only one compound and a single layer hole transport layer containing a plurality of compounds. The hole transport region can also be a multi-layer structure including at least one of a hole injection layer (HIL), a hole transport layer (HTL), and an electron blocking layer (EBL).

[0050] The material of the hole transport layer can be selected from, but not limited to, a phthalocyanine derivative such as CuPc, a conductive polymer or a polymer containing a conductive dopant such as polyphenylene vinylene, polyaniline / dodecylbenzenesulfonic acid (PANI / DBSA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate) (PEDOT / PSS), polyaniline / camphor sulfonic acid (PANI / CSA), polyaniline / poly(4-styrenesulfonate) (PANI / PSS), an aromatic amine derivative such as the compounds shown in HT-1 to HT-30 below, or any combination thereof: .

[0051] The hole injection layer can be a single compound material or a combination of multiple compound materials. For example, the hole injection layer can employ one or more of the compounds described above as HT-1 to HT-30, or one or more of the compounds described below as HI-1 to HI-3; or can employ one or more of the compounds described above as HT-1 to HT-30 doped with one or more of the compounds described below as HI-1 to HI-3:

[0052] .

[0053] The OLED organic material layer can also include an electron transport zone between the light-emitting layer and the cathode. The electron transport zone can be a single-layer structure electron transport layer (ETL), including a single-layer electron transport layer containing only one compound and a single-layer electron transport layer containing multiple compounds. The electron transport zone can also be a multi-layer structure including at least one of an electron injection layer (EIL), an electron transport layer (ETL), and a hole blocking layer (HBL).

[0054] The electron transport layer material can be selected from, but not limited to, one or more of the following combinations of ET-1 to ET-36:

[0055] .

[0056] The device also includes an electron injection layer between the electron transport layer and the cathode, and the electron injection layer material includes, but is not limited to, one or more of the following combinations:

[0057] LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, Ca.

[0058] According to the technical solutions described above, compared with the prior art, the present application has the following beneficial effects:

[0059] The application provides an organic electroluminescent material, which is generated by selecting coordination with a specific heterocyclic ligand, changing the combination of substituents on 8-(pyridin-2-yl)benzofuro[2,3-b]pyridine, increasing -CN, -F, branched alkyl, substituted or unsubstituted piperidyl, substituted or unsubstituted pyrrolidyl, substituted or unsubstituted aryl and substituted or unsubstituted cycloalkyl, improving the intermolecular spatial configuration, having good spatial torsion capacity, thereby avoiding carrier migration to change the position of the substituent or the activity of the substituent, so that the obtained organic electroluminescent material is used in an organic electroluminescent device, the maximum external quantum efficiency of the device is improved, the service life is delayed, and the driving voltage is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0060] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only a part of the embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor on the basis of the provided drawings.

[0061] Figure 1 The nuclear magnetic resonance hydrogen spectrum of Z-1. DETAILED DESCRIPTION

[0062] The technical solutions of the present application will be described clearly and completely in combination with the embodiments of the present application and the related drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0063] The embodiments of the present application specifically disclose an organic electroluminescent material and an organic electroluminescent device comprising the same.

[0064] The features and performances of the present application will be further described in detail below in combination with the embodiments.

[0065] Embodiment 1

[0066]

[0067] Under the protection of nitrogen, 8-chloro-[1]benzofuran[2,3-b]pyridine (1 eq, CAS: 2747969-64-6), anhydrous potassium carbonate (3 eq) were placed into the reaction system, toluene, anhydrous ethanol, pure water were added, Pd(PPh3)4 (0.015 eq) was added under the protection of nitrogen, (4-chloropyridin-2-yl)boronic acid (1 eq, CAS: 870459-91-9) was added in three batches at an interval of 1 hour, after addition, it was refluxed at 100°C for 24 hours under the protection of nitrogen, and then cooled to 25°C. After the reaction was cooled, ethyl acetate was extracted, saturated brine was washed three times, anhydrous magnesium sulfate was dried, and concentrated under reduced pressure. The crude product was column chromatographed (200-300 mesh, 500 g) to remove impurities, the developing agent was EA: PE = 1:15, the receiving liquid was spun to no liquid flow, and vacuum drying was performed to obtain the compound intermediate 1 with a yield of 59.7%.

[0068]

[0069] Under the protection of nitrogen, intermediate 1 (1 eq), anhydrous potassium carbonate (3 eq) were placed into the reaction system, toluene, anhydrous ethanol, pure water were added, Pd(PPh3)4 (0.015 eq) was added under the protection of nitrogen, [4-(4,4-dimethylpiperidin-1-yl)phenyl]boronic acid (1 eq, CAS: 2766475-50-5) was added in three batches at an interval of 1 hour, after addition, it was refluxed at 110°C for 24 hours under the protection of nitrogen, and then cooled to 25°C. After the reaction was cooled, ethyl acetate was extracted, saturated brine was washed three times, anhydrous magnesium sulfate was dried, and concentrated under reduced pressure. The crude product was column chromatographed (200-300 mesh, 500 g) to remove impurities, the developing agent was EA: PE = 1:20, the receiving liquid was spun to no liquid flow, and vacuum drying was performed to obtain the compound of formula II-1 with a yield of 91.6%.

[0070]

[0071] Under the protection of nitrogen, formula V-1 compound (1 eq) and IrCl3·3H2O (0.4 eq) were placed into the reaction system, a mixed solution of ethylene glycol ether and pure water was added, and it was refluxed at 120°C for 36 hours under the protection of nitrogen, and then cooled to room temperature. Precipitate was precipitated, the precipitate was suction filtered, washed with water, anhydrous ethanol and petroleum ether in sequence, and dried to obtain the compound of formula IV-1 with a yield of 81.9%.

[0072]

[0073] Under nitrogen protection system, take compound of formula IV-1 (1 eq), add silver trifluoromethanesulfonate (2.2 eq), then add dichloromethane and methanol into the system, and reflux at 25℃ for 48 hours under nitrogen protection, and then cool to room temperature, and then concentrate the filtrate to solid to obtain compound of formula III-1 with a yield of 94.6%.

[0074]

[0075] Under nitrogen protection system, take compound of formula III-1 (1 eq), add compound of formula II-1 (2.2 eq), then add anhydrous ethanol into the system, and reflux at 80℃ for 36 hours under nitrogen protection, and then filter, wash with alcohol, and dry; use dichloromethane as solvent, and then use silica gel column chromatography, concentrate the filtrate to solid to obtain final compound Z-1 (11.78 g, yield 59.2%).

[0076] HPLC purity: greater than 99.5%;

[0077] MS (ESI, m / Z): [M+H]+: 933.38.

[0078] The nuclear magnetic resonance hydrogen spectrum of compound Z-1 prepared in Example 1 is shown in Figure 1 .

[0079] In addition, it needs to be noted that other compounds of the present application can be obtained by referring to the preparation methods of the above-mentioned examples, which will not be described here.

[0080] Device Example 1:

[0081] An organic electroluminescence device is prepared using the organic electroluminescence material of formula Z-1

[0082] An ITO glass substrate with a coating thickness of 1500 Å is cleaned in distilled water for 2 times, and ultrasonic washing is performed for 30 minutes. After the distilled water cleaning is completed, isopropyl alcohol, acetone, and methanol solvents are sequentially ultrasonic washed, and then dried, and transferred to a plasma cleaning machine. The substrate is washed for 10 minutes in the plasma cleaning machine, and then transferred to an evaporation machine.

[0083] First, a hole injection layer of HI-1 with a thickness of 100 Å is evaporated on the ITO (anode), and then a hole transport layer of HT-4 with a thickness of 900 Å is evaporated on the hole injection layer, and then a light-emitting layer of a host material 4,4'-N,N'-dicarbazolyl biphenyl ("CBP") and a doped material compound of formula Z-1 with a weight ratio of 90:10 is evaporated with a thickness of 400 Å, and then an electron transport layer of ET-4 with a thickness of 400 Å is evaporated on the light-emitting layer, and then an electron injection layer material Liq with a thickness of 150 Å is evaporated on the electron transport layer, and finally a cathode material Al with a thickness of 1000 Å is evaporated on the electron injection layer, so as to obtain an organic electroluminescence device.

[0084] wherein the structure of Liq is as follows:

[0085]

[0086] The performance of the obtained devices was tested for light emitting characteristics. The driving voltage, lifetime, and luminous efficiency were evaluated using a KEITHLEY 2400 source measurement unit and a CS-2000 spectroradiometric luminance meter.

[0087] Device Comparative Example 1 - Device Comparative Example 4:

[0088] The only difference between Device Comparative Example 1 and Device Example 1 is that the compound of the doping material of Formula Z-1 is replaced by the structure shown in Comparative Example 1 - Comparative Example 4, respectively, and then the organic electroluminescent device (Device Comparative Example 1 - Device Comparative Example 4) is prepared according to the same method as Device Example 1, wherein the structure of the compound of the light-emitting layer doping material is as follows:

[0089]

[0090]

[0091] Device Example 2 - Device Example 45:

[0092] Referring to the method of Device Example 1 described above, the only difference is that the compound of the doping material of Formula Z-1 is replaced by Z-8, Z-18, Z-22, Z-57, Z-78, Z-100, Z-144, Z-166, Z-173, Z-206, Z-255, Z-270, Z-311, Z-341, Z-356, Z-413, Z-430, Z-464, Z-480, Z-503, Z-540, Z-566, Z-579, Z-592, Z-603, Z-606, Z-622, Z-633, Z-667, Z-680, Z-693, Z-716, Z-744, Z-758, Z-786, Z-792, Z-804, Z-846, Z-866, Z-889, Z-910, Z-919, Z-1024, Z-1085, respectively, and then the organic electroluminescent device (Device Example 2 - Device Example 45) is prepared according to the same method as Device Example 1.

[0093] The driving voltage, luminous efficiency, and lifetime of the organic electroluminescent devices obtained from the above-described Device Examples and Device Comparative Examples were characterized at a brightness of 15000 (nits), and the test results are shown in Table 1.

[0094] ​​It should be noted that the relative value is a comparison result between numbers, and the relative value is usually expressed in percentage or decimal form to indicate the degree of change of a number relative to other numbers. In addition, in the industrial field, the relative value can also be used to measure the degree of change of production efficiency, and to evaluate the quality and stability of products, etc.

[0095] Table 1

[0096]

[0097] As can be seen from Table 1:

[0098] 1. By comparing the device test data, it is found that by changing the combination of substituents on 8-(pyridin-2-yl)benzofuro[2,3-b]pyridine, increasing -CN, -F, branched alkyl, substituted or unsubstituted piperidyl, substituted or unsubstituted pyrrolidyl, substituted or unsubstituted aryl, and substituted or unsubstituted cycloalkyl, increasing the electron-withdrawing group, improving the intermolecular spatial configuration, having good spatial torsion ability, effectively adjusting the HOMO and LUMO energy levels, thereby avoiding carrier migration, using the compound as a specific dopant material for the light-emitting layer and applying it to an organic electroluminescent device, the driving voltage of the device is reduced, thereby avoiding carrier migration, so that the compound as a light-emitting layer dopant material, the organic electroluminescent device prepared has a significantly reduced driving voltage, and the luminous efficiency and lifetime are significantly improved.

[0099] 2. The organic electroluminescent device prepared by using the compound provided in the present application as a light-emitting layer dopant material has a significantly reduced driving voltage and significantly enhanced luminous efficiency compared to the organic electroluminescent device prepared by using Comparative Examples 1-4 as a light-emitting layer dopant material.

[0100] The above description of disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An organic electroluminescent material, characterized in that: The structure of the organic electroluminescent material is shown in formula I: ； wherein is selected from substituted or unsubstituted piperidinyl, substituted or unsubstituted pyrrolidinyl, and the point of attachment is N on the nitrogen heterocycle; X is independently selected from O, S, Se, NRx, CRxRy, SiRxRy, GeRxRy; wherein, Rxand Ryare selected from hydrogen, methyl, -F, -D, -CN, -CD3, phenyl; one of R1, R2, R3, and R4is connected to one of R1, R2, R3, and R4is connected to - F, -CD3, -CN, phenyl, methyl, ethyl, propyl, butyl, pentyl; R5, R6, R7, R8and R9are each independently selected from hydrogen, -D, -F, -CN, -CD3, substituted or unsubstituted phenyl, substituted or unsubstituted methyl, substituted or unsubstituted ethyl, substituted or unsubstituted propyl, substituted or unsubstituted butyl, substituted or unsubstituted pentyl, substituted or unsubstituted cyclohexyl; R 10 , R 11 , R 12 , R 13 , and R 14 are each independently selected from the group consisting of hydrogen, -D, -F, -CN, -CD3, a substituted or unsubstituted phenyl, methyl, ethyl, propyl, butyl, trimethylgermanium, trimethylsilicon, or a combination of any one or at least two of the following groups: ； R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 and R 22 are each independently selected from any one or more combinations of hydrogen, -D, -CN, -F, -CF3, C1-C20 alkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, substituted or unsubstituted C3-C20 cycloalkyl, trimethylgermanium, trimethylsilicon; The hydrogen atoms in the above groups are partially or fully replaced by deuterium; substituted or unsubstituted one, two or more substituents selected from deuterium; halogen group; cyano group; C1-C20alkyl; C3-C20cycloalkyl; C6-C30aryl; C3-C20heterocyclic group, or substituted with two or more substituents mentioned above, or without substituents; and * is the connecting position.

2. The organic electroluminescent material according to claim 1, characterized in that X is independently selected from O, S, Se, NRx, CRxRy, SiRxRy, GeRxRy; wherein, Rxand Ryare selected from hydrogen, methyl.

3. The organic electroluminescent material according to claim 1, characterized in that selected from the group consisting of: 。 4. The organic electroluminescent material according to claim 1, characterized in that ligand selected from the following structures: 。 5. The organic electroluminescent material according to claim 1, characterized in that, ligand selected from the following structures: 。 6. An organic electroluminescent material, characterized by The organic electroluminescent material is selected from one of the following structures: 。 7. An organic electroluminescent device, characterized by comprising The organic electroluminescent device comprises an anode, a cathode, and an organic material layer disposed between the anode and the cathode; the organic material layer comprises the organic electroluminescent material according to claim 1.

8. The organic electroluminescent device according to claim 7, characterized in that The organic electroluminescent device comprises a light-emitting layer, and the light-emitting layer comprises the organic electroluminescent material according to claim 1.

9. The organic electroluminescent device according to claim 8, characterized in that The light-emitting layer of the organic electroluminescent device comprises a host material and a dopant material; the dopant material comprises the organic electroluminescent material according to claim 1.

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