Compound containing boron and nitrogen and application thereof in OLED (Organic Light Emitting Diode)

Abstract

According to the boron-nitrogen-containing compound and the application thereof in the OLED, the structure of the boron-nitrogen-containing compound is designed, the obtained boron-nitrogen-containing compound has excellent performance, and an organic light-emitting device prepared by using the boron-nitrogen-containing compound as a light-emitting layer material has relatively low driving voltage and relatively high current efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of organic photoelectric display, and in particular relates to a boron-nitrogen-containing compound and an application thereof in OLED. Background Art

[0002] Organic light emitting diodes (OLEDs) are display components that utilize the phenomenon of self-luminescence and have a wide viewing angle. Compared with liquid crystal display components, OLED components are thinner and lighter, have a faster response speed, and can achieve flexible displays. Therefore, their application as full-color display components or lighting equipment is highly anticipated.

[0003] Generally, organic light emitting phenomenon refers to the phenomenon of converting electrical energy into light energy using organic substances. An organic light emitting element using the organic light emitting phenomenon generally has a structure including an anode, a cathode, and an organic material layer interposed between the anode and the cathode.

[0004] Among them, the organic layer is composed of a multilayer structure composed of different substances in most cases in order to improve the efficiency and stability of the organic light-emitting element. For example, it can be composed of a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, etc. If a voltage is applied between the two electrodes in the structure of such an organic light-emitting element, the holes in the anode will be injected into the organic layer, and the electrons in the cathode will also be injected into the organic layer. When the injected holes and electrons meet, excitons are formed. When the excitons release energy and transition to the ground state, photons will be emitted, thereby generating light. Such organic light-emitting elements are widely recognized to have the characteristics of self-luminescence, high brightness, high efficiency, low driving voltage, wide viewing angle, high contrast, and high-speed responsiveness.

[0005] At present, the research on organic electroluminescent materials has been widely carried out in academia and industry. Among them, blue light materials are an important component of organic electroluminescent devices. The transmission performance and luminous efficiency of blue light materials restrict the industrialization of light-emitting devices. Therefore, designing and finding a compound as a new OLED material to overcome its shortcomings in practical applications is the focus of OLED material research and the future research and development trend. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a boron-nitrogen-containing compound and its application in OLED. The present invention is designed through the structure of the boron-nitrogen-containing compound, and the obtained boron-nitrogen-containing compound has excellent performance and is used in an organic electroluminescent device, so that the device has a lower driving voltage and a higher current efficiency.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In one aspect, the present invention provides a boron-nitrogen-containing compound, wherein the boron-nitrogen-containing compound has a structure as shown in Formula I:

[0009]

[0010] X 1 , X 2 , X 3 and Y are each independently selected from oxygen, sulfur or

[0011] a, b, c are each independently an integer greater than or equal to 0 and less than or equal to 4 (e.g., 0, 1, 2, 3 or 4);

[0012] R 1 , R 2 , R 3 , R 4 , R 5 , R 6 are the same as or different from each other and are each independently selected from hydrogen, deuterium, substituted or unsubstituted C 1 ~C 12 Alkyl, substituted or unsubstituted C 6 ~C 30 Aryl, substituted or unsubstituted C 3 ~C 30 heteroaryl, substituted or unsubstituted diarylamine; R 1 , R 2 and R 3 Each group exists independently, and adjacent groups can be connected to form a ring;

[0013] Ar 1 is substituted or unsubstituted C 6 ~C 30 Aryl, substituted or unsubstituted C 3 ~C 30 heteroaryl;

[0014] When the substituted or unsubstituted group contains a substituent, the substituent is selected from deuterium, F, CN, C 1 ~C 12 Alkyl, C 6 ~C 30 Aryl or C 3 ~C 30 The heteroaryl group.

[0015] All hydrogen atoms in Formula I can be independently replaced by deuterium, F, CN, C 1 ~C 12 Alkyl, C 6 ~C 30 Aryl or C3 ~C 30 is substituted with a heteroaryl group.

[0016] Preferably, the boron-nitrogen-containing compound is a compound having any of the following structures:

[0017]

[0018] X 1 , X 2 , X 3 , a, b, c, R 1 , R 2 , R 3 , R 4 The definition of is the same as that in Chemical Formula I.

[0019] Preferably, the boron-nitrogen-containing compound is a compound having any of the following structures:

[0020]

[0021] X 2 , X 3 , a, b, R 1 , R 2 , R 4 The definition of is the same as that in Chemical Formula I.

[0022] Preferably, the C 1 ~C 12 The alkyl group is selected from methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl, tert-pentyl, n-hexyl or cyclohexyl.

[0023] More preferably, the C 1 ~C 12 The alkyl group is selected from methyl, ethyl, isopropyl or tert-butyl.

[0024] Preferably, the C 6 ~C 30 The aromatic group is the general term for the monovalent group left after removing a hydrogen atom from the aromatic carbon of the aromatic hydrocarbon molecule; 6 ~C 30 The aryl group includes a monocyclic aryl group or a condensed ring aryl group.

[0025] Preferably, the C 6 ~C 30 The aryl group of is selected from phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, indenyl, fluorenyl, perylenyl, phenanthryl, pyrenyl, fluoranthenyl, fluorenyl, spirobifluorenyl or triphenylenyl.

[0026] More preferably, the C 6 ~C 30The aryl group is selected from phenyl, biphenyl and naphthyl.

[0027] Preferably, the C 3 ~C 30 The heteroaryl group is a general term for groups in which one or more aromatic carbon atoms in an aromatic group are replaced by heteroatoms; 3 ~C 30 The heteroatom of the heteroaryl is selected from oxygen, sulfur, nitrogen or silicon; 3 ~C 30 The heteroaryl group includes a monocyclic heteroaryl group or a condensed-ring heteroaryl group.

[0028] Preferably, the C 3 ~C 30 The heteroaryl group is selected from pyridyl, benzofuranyl, benzothiophenyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, benzofuranocarbazolyl, benzofuranothiophenyl or triazine.

[0029] More preferably, the C 3 ~C 30 The heteroaryl group is selected from pyridyl, dibenzofuranyl, dibenzothienyl or carbazolyl.

[0030] Preferably, Ar 1 is phenyl, C1-C5 alkyl-substituted phenyl, biphenyl, C1-C5 alkyl-substituted biphenyl, terphenyl, C1-C5 alkyl-substituted terphenyl, phenyl-substituted terphenyl;

[0031] Preferably, X 2 Selected from The wavy line represents the attachment site of the group.

[0032] Preferably, X 3 Selected from O, S, The wavy line represents the attachment site of the group.

[0033] Preferably, R 1 , R 2 and R 3 Independently selected from hydrogen, C1-C5 alkyl, diphenylamino, C1-C5 alkyl-substituted diphenylamino, carbazolyl, or C1-C5 alkyl-substituted carbazolyl.

[0034] Preferably, R 1 , R 2 and R 3 are independently selected from hydrogen, tert-butyl, The wavy line represents the attachment site of the group.

[0035] Preferably, R4 Selected from hydrogen, cyano, phenyl, C1-C5 alkyl, C1-C5 alkyl-substituted phenyl, pyridyl, biphenyl, C1-C5 alkyl-substituted biphenyl, terphenyl, C1-C5 alkyl-substituted terphenyl, phenyl-substituted terphenyl, carbazolyl or C1-C5 alkyl-substituted carbazolyl.

[0036] More preferably, R 4 Selected from hydrogen, cyano, Phenyl, pyridyl,

[0037] Preferably, the R 1 , R 2 and R 3 Each group exists independently, and adjacent groups can be connected to form a ring, such as the following ring structure:

[0038] The bond with the * is the shared bond with the aromatic ring;

[0039] Preferably, the boron-nitrogen-containing compound is selected from any one of compounds 1 to 96:

[0040]

[0041]

[0042]

[0043]

[0044]

[0045] The present invention lists some specific structural forms of the boron-nitrogen-containing compounds, but the boron-nitrogen-containing compounds of the present invention are not limited to these listed chemical structures. 1 , X 2 , X 3 , a, b, c, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 All structures that meet the above restrictions should be included.

[0046] In a second aspect, the present invention provides an organic electroluminescent device, wherein the organic electroluminescent device comprises the boron-nitrogen-containing compound as described in the first aspect.

[0047] Preferably, the organic electroluminescent device comprises a first electrode, a second electrode and an organic layer disposed between the first electrode and the second electrode; the material of the organic layer comprises the boron-nitrogen-containing compound as described in the first aspect.

[0048] Preferably, the organic layer includes a light-emitting layer, and the material of the light-emitting layer includes the boron-nitrogen-containing compound as described in the first aspect.

[0049] Furthermore, the light-emitting layer is prepared by an evaporation method.

[0050] In a third aspect, the present invention provides a display device, comprising the organic electroluminescent device as described in the second aspect.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] The present invention designs the structure of the boron-nitrogen-containing compound to obtain a boron-nitrogen-containing compound with good luminescence performance, which can be used to prepare an organic electroluminescent device, especially as a light-emitting layer material in an organic electroluminescent device, and can effectively reduce the driving voltage of the organic electroluminescent device and improve the current efficiency of the organic electroluminescent device. DETAILED DESCRIPTION

[0053] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0054] Synthesis Example 1

[0055] This embodiment provides a method for synthesizing compound 1, as follows:

[0056]

[0057] (1) Synthesis of intermediate 1-1

[0058] Under nitrogen protection, add 200 mL of dry toluene, 0.1 mol of chloride-1, 0.1 mol of amine-1, and 0.001 mol of Pd(dba) into a 500 mL three-necked flask. 2 (bis(dibenzylideneacetonepalladium), 4g of a 10% tri-tert-butylphosphine toluene solution (the amount of tri-tert-butylphosphine is 0.002mol) and 0.3mol of sodium tert-butoxide, heated to reflux reaction for 12h, cooled to room temperature, added water to separate, then the organic layer was washed with water until neutral, dried with magnesium sulfate, filtered to remove magnesium sulfate, concentrated to dryness, and crystallized with ethanol to obtain intermediate 1-1;

[0059] The mass spectrometry of intermediate 1-1 revealed a mass-to-charge ratio (m / z) of 652.2.

[0060] (2) Synthesis of intermediate 1-2

[0061] Referring to the synthesis method of intermediate 1-1, intermediate 1-1 is used to replace chloride-1 in an equal amount, and diphenylamine is used to replace amine-1 in an equal amount, and other conditions remain unchanged to obtain intermediate 1-2;

[0062] The mass spectrometry of intermediate 1-2 revealed a mass-to-charge ratio (m / z) of 785.3.

[0063] (3) Synthesis of Compound 1

[0064] Under nitrogen protection, the reaction bottle containing 0.01 mol of intermediate 1-2 and 100 ml of o-dichlorobenzene was cooled to 0°C, and 0.05 mol of boron tribromide was added dropwise. After the addition was completed, the temperature was raised to 150°C and stirred for 24 hours. When the reaction was completed, saturated Na 2 S 2 O 3 Aqueous solution and saturated NaHCO 3 The organic layer was washed with water until neutral, dried with magnesium sulfate, filtered to remove the magnesium sulfate, concentrated to dryness, separated by silica gel column chromatography, eluted with petroleum ether: ethyl acetate = 10: 1 (volume ratio), concentrated, and recrystallized with toluene and ethanol to obtain compound 1.

[0065] The obtained compound 1 was subjected to mass spectrometry detection, and the mass-to-charge ratio (m / z) was measured to be 793.3.

[0066] Synthesis Example 2

[0067] This embodiment provides a method for synthesizing compound 2, as described below:

[0068]

[0069] (1) Synthesis of Chloroform-2

[0070] Under nitrogen protection, add 400 ml of toluene, 200 ml of ethanol, 200 ml of water, 0.1 mol of bromide-1, 0.12 mol of phenylboric acid, 0.2 mol of potassium carbonate and 0.05 mol of tetrakis(triphenylphosphine)palladium into the reaction bottle, heat to 78°C and stir to react for 6 hours, separate the liquids, dry the organic phase and perform column chromatography, concentrate the filtrate, and recrystallize the crude solid from toluene and ethanol to obtain bromide-2.

[0071] Mass spectrometry was performed on the chloro compound-2, and the mass-to-charge ratio (M / Z) was measured to be 388.0.

[0072] (2) Synthesis of Compound 2

[0073] Referring to the synthesis method of Synthesis Example 1, the chloro compound-1 in Synthesis Example 1 is replaced by an equal molar amount of chloro compound-2, and other conditions remain unchanged to obtain Compound 2.

[0074] Mass spectrometry detection was performed on compound 2: the measured mass spectrum (m / z) was: 718.2.

[0075] Synthesis Example 3

[0076] This embodiment provides a method for synthesizing compound 6, as follows:

[0077]

[0078] (1) Synthesis of Chloroform-3

[0079] Under nitrogen protection, add 400 ml of toluene, 200 ml of ethanol, 200 ml of water, 0.1 mol of bromide-2, 0.12 mol of 3-chloro-5-fluorophenylboric acid, 0.2 mol of potassium carbonate and 0.05 mol of tetrakis(triphenylphosphine)palladium into the reaction bottle, heat to 78°C and stir to react for 6 hours, separate the layers, dry the organic phase and perform column chromatography, concentrate the filtrate, and recrystallize the crude solid from toluene and ethanol to obtain bromide-3.

[0080] The mass spectrometry of the chloro compound-3 was performed, and the mass-to-charge ratio (M / Z) was measured to be 372.1.

[0081] (2) Synthesis of Intermediate 6-1

[0082] Referring to the synthesis method of Synthesis Example 1, the chloro compound-3 is used in place of the chloro compound-1 in Synthesis Example 1 with an equal molar amount, and other conditions remain unchanged, to obtain the intermediate 6-1.

[0083] The intermediate 6-1 was subjected to mass spectrometry detection: the measured charge-to-mass ratio (m / z) was 561.2.

[0084] (3) Synthesis of Intermediate 6-2

[0085] 0.1 mol of intermediate 6-1 and 0.15 mol of phenol were added to a reaction flask, and 1000 ml of DMF and 0.2 mol of potassium carbonate were added. The temperature was raised to 110°C under nitrogen protection and stirred for 12 h. The temperature was then lowered to room temperature. The reaction solution was poured into 2 L of pure water. A large amount of solid was precipitated. The filter cake was refluxed and slurried once with 500 ml of ethanol, and then filtered. The solid was recrystallized with toluene to obtain intermediate 6-2.

[0086] The intermediate 6-2 was subjected to mass spectrometry detection: the measured charge-to-mass ratio (m / z) was 635.2.

[0087] (4) Synthesis of Intermediate 6

[0088] Referring to the synthesis method of Synthesis Example 1, intermediate 1-2 in Synthesis Example 1 is replaced by intermediate 6-2 in an equal molar amount, and compound 6 can be obtained while keeping other conditions unchanged.

[0089] Mass spectrometry detection was performed on compound 6: the measured mass spectrum (m / z) was: 643.2.

[0090] Synthesis Example 4

[0091] This embodiment provides a method for synthesizing compound 33, as described below:

[0092]

[0093] Referring to the synthesis method of Synthesis Example 1, Compound 33 can be obtained by replacing amine-1 in Synthesis Example 1 with an equal molar amount of amine-2 and using an equal molar amount of di(4-tert-butylphenyl)amine while keeping other conditions unchanged.

[0094] The mass spectrometry of compound 33 revealed a charge-to-mass ratio (m / z) of 1017.5.

[0095] Synthesis Example 5

[0096] This embodiment provides a method for synthesizing compound 34, as described below:

[0097]

[0098] Referring to the synthesis method of Synthesis Example 4, the chloro compound-1 in Synthesis Example 4 is replaced by an equal molar amount of chloro compound-2, and the other conditions remain unchanged to obtain Compound 34.

[0099] The mass spectrometry of compound 34 was performed, and the charge-to-mass ratio (m / z) was measured to be 942.5.

[0100] Synthesis Example 6

[0101] This embodiment provides a method for synthesizing compound 43, as described below:

[0102]

[0103] Referring to the synthesis method of Synthesis Example 4, the chloro compound-1 in Synthesis Example 4 is replaced by an equal molar amount of chloro compound-4, and other conditions remain unchanged to obtain Compound 43.

[0104] The mass spectrometry of compound 43 revealed a charge-to-mass ratio (m / z) of 922.5.

[0105] By referring to the synthesis methods of the above compounds and combining with commonly used organic synthesis methods, compounds 38, 40, 46, 52, 81, 87, 90, 93 and 96 were prepared and subjected to mass spectrometry detection. The test results are shown in Table 1 below.

[0106] Table 1

[0107]

[0108]

[0109]

[0110]

[0111] Other compounds whose specific synthesis steps are not listed can be prepared by common knowledge in the art in combination with the above embodiments.

[0112] The specific structures of the compounds used in the following device examples and device comparative examples are shown below:

[0113]

[0114]

[0115] In the following device examples, the boron-nitrogen-containing compound provided by the present invention is selected as the doping material for the light-emitting layer in the organic electroluminescent device, and in the device comparative examples, the above-mentioned BD-1, BD-2, and BD-3 are selected as the doping material for the light-emitting layer in the organic electroluminescent device.

[0116] Device Example 1

[0117] This device embodiment provides an organic electroluminescent device, using the compound 1 provided in Synthesis Example 1 of the present invention as a doping material for the light-emitting layer; and in this embodiment, the light-emitting layer is prepared by evaporation.

[0118] The structure of the organic electroluminescent device is:

[0119] ITO / HT (40 nm) / BH: 3% Compound 1 / TPBI (30 nm) / LiF (0.5 nm) / Al (150 nm).

[0120] The preparation method of the organic electroluminescent device is as follows:

[0121] The glass substrate coated with an ITO transparent conductive layer (as an anode) is ultrasonically treated in a cleaning agent, then rinsed in deionized water, ultrasonically degreased in a mixed solvent of acetone and ethanol, baked in a clean environment until the water is completely removed, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam to improve the properties of the surface and enhance the binding ability with the hole injection layer;

[0122] The glass substrate was placed in a vacuum chamber and evacuated to 1×10 -5 ~9×10 -6 Pa, HT was vacuum evaporated on the anode as a hole transport layer, the evaporation rate was 0.1nm / s, and the evaporation film thickness was 40nm;

[0123] The light-emitting layer is vacuum-deposited on the hole transport layer, the deposition rate is 0.1 nm / s, the total deposition film thickness is 30 nm, the main material of the light-emitting layer is BH, and the doping material is the compound 1 provided by the present invention. 3% refers to the doping ratio of the doping material, that is, the volume ratio of the main material of the light-emitting layer to the doping material is 97:3.

[0124] TPBI was vacuum-deposited on the light-emitting layer as the electron transport layer of the device, with a deposition rate of 0.1 nm / s and a total deposition film thickness of 30 nm.

[0125] 0.5 nm of LiF and 150 nm of Al were vacuum-deposited on the electron transport layer to serve as an electron injection layer and a cathode.

[0126] The brightness, driving voltage and current efficiency of the prepared organic electroluminescent device were measured.

[0127] Device Examples 2 to 15

[0128] Device Examples 2 to 15 respectively provide an organic electroluminescent device, which differs from Device Example 1 only in that the doping materials of the light-emitting layer are different (see Table 2 for details), and other conditions are the same as those of Device Example 1.

[0129] Device Comparison Examples 1 to 3

[0130] Device Comparative Examples 1 to 3 respectively provide an organic electroluminescent device, which differs from Device Example 1 only in that the doping materials of the light-emitting layer are different (see Table 2 for details), and other conditions are the same as those of Device Example 1.

[0131] Performance Testing

[0132] Test the driving voltage, current efficiency and life LT90 of the OLED devices provided above; LT90 refers to the time required for the brightness to drop to 90% of the original brightness while maintaining the current density at the initial brightness of 1000nit. The test items include the brightness, driving voltage and current efficiency of the organic electroluminescent device. The driving voltage, current efficiency and LT90 data are all based on a brightness of 1000cd / m 2 The relative values ​​of the device performance when (based on the test data of device comparative example 1), the test results of the organic electroluminescent device performance are shown in the following Table 2.

[0133] Table 2

[0134]

[0135]

[0136] From the above content, it can be seen that the present invention obtains a compound suitable for use as a doping material for the light-emitting layer through structural design, and the organic electroluminescent device prepared thereby has a lower driving voltage, a higher current efficiency and a longer service life.

[0137] The applicant declares that the present invention illustrates the boron-nitrogen-containing compounds and their applications through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A boron-nitrogen-containing compound, characterized in that The boron-nitrogen-containing compound has a structure as shown in Formula I: X1, X2, X3 and Y are each independently selected from oxygen, sulfur or a, b, and c are each independently an integer greater than or equal to 0 and less than or equal to 4; R1, R2, R3, R5, and R6 are the same or different from each other and are each independently selected from hydrogen, deuterium, substituted or unsubstituted C1-C 12 Alkyl, substituted or unsubstituted C6~C 30 Aryl, substituted or unsubstituted C3~C 30 a heteroaryl group, a substituted or unsubstituted diarylamine group; R4 is selected from substituted or unsubstituted C1-C 12 Alkyl, substituted or unsubstituted C6~C 30 Aryl, substituted or unsubstituted C3~C 30 heteroaryl; R1, R2 and R3 exist independently, and adjacent groups can be connected to form a ring; Ar1 is substituted or unsubstituted C6~C 30 Aryl, substituted or unsubstituted C3~C 30 heteroaryl; When the substituted or unsubstituted group contains a substituent, the substituent is selected from deuterium, F, CN, C1-C 12 Alkyl, C6~C 30 Aryl or C3~C 30 The heteroaryl group. All hydrogen atoms in Formula I can be independently replaced by deuterium, F, CN, C1-C 12 Alkyl, C6~C 30 Aryl or C3~C 30 is substituted with a heteroaryl group.

2. The boron-nitrogen-containing compound according to claim 1, characterized in that The boron-nitrogen-containing compound is a compound having any of the following structures: The definitions of X1, X2, X3, a, b, c, R1, R2, R3, and R4 are the same as those in claim 1.

3. The boron-nitrogen-containing compound according to claim 1, characterized in that The boron-nitrogen-containing compound is a compound having any of the following structures: X2, X3, a, b, R1, R2, and R4 are defined as in claim 1.

4. The boron-nitrogen-containing compound according to any one of claims 1 to 3, characterized in that C1~C 12 The alkyl group is selected from methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl, tert-pentyl, n-hexyl or cyclohexyl; More preferably, the C1 to C 12 The alkyl group is selected from methyl, ethyl, isopropyl or tert-butyl; Preferably, the C6~C 30 The aryl group is selected from phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, indenyl, fluorenyl, perylenyl, phenanthryl, pyrenyl, fluoranthenyl, fluorenyl, spirobifluorenyl or triphenylenyl; More preferably, the C6~C 30 The aryl group is selected from phenyl, biphenyl and naphthyl; Preferably, the C3 to C 30 The heteroaryl group is selected from pyridyl, benzofuranyl, benzothiophenyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, benzofuranocarbazolyl, benzofuranothiophenyl or triazine; More preferably, the C3 to C 30 The heteroaryl group is selected from pyridyl, dibenzofuranyl, dibenzothienyl or carbazolyl.

5. The boron-nitrogen-containing compound according to any one of claims 1 to 4, characterized in that Ar1 is phenyl, C1-C5 alkyl-substituted phenyl, biphenyl, C1-C5 alkyl-substituted biphenyl, terphenyl, C1-C5 alkyl-substituted terphenyl, phenyl-substituted terphenyl; Preferably, X2 is selected from The wavy lines represent the attachment sites of the groups; Preferably, X3 is selected from O, S, The wavy lines represent the attachment sites of the groups; Preferably, R1, R2 and R3 are independently selected from hydrogen, C1-C5 alkyl, diphenylamino, C1-C5 alkyl-substituted diphenylamino, carbazole or C1-C5 alkyl-substituted carbazole; Preferably, R1, R2 and R3 are independently selected from hydrogen, tert-butyl, The wavy lines represent the attachment sites of the groups; Preferably, R4 is selected from cyano, phenyl, C1-C5 alkyl, C1-C5 alkyl-substituted phenyl, pyridyl, biphenyl, C1-C5 alkyl-substituted biphenyl, terphenyl, C1-C5 alkyl-substituted terphenyl, phenyl-substituted terphenyl, carbazolyl or C1-C5 alkyl-substituted carbazolyl; Preferably, R4 is selected from cyano, Phenyl, pyridyl, Preferably, the R1, R2 and R3 exist independently, and adjacent groups can be connected to each other to form the following ring structure: The bond with * is the shared bond with the aromatic ring.

6. The boron-nitrogen-containing compound according to any one of claims 1 to 5, characterized in that The boron-nitrogen-containing compound is selected from any one of compounds 1 to 96:

7. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises the boron-nitrogen-containing compound according to any one of claims 1 to 6.

8. The organic electroluminescent device according to claim 7, characterized in that: The organic electroluminescent device comprises a first electrode, a second electrode and an organic layer disposed between the first electrode and the second electrode; the material of the organic layer comprises the boron-nitrogen-containing compound according to any one of claims 1 to 6.

9. The organic electroluminescent device according to claim 7, characterized in that: The organic layer includes a light-emitting layer, and the material of the light-emitting layer includes the boron-nitrogen-containing compound according to any one of claims 1 to 6; Preferably, the light-emitting layer is prepared by evaporation.

10. A display device, characterized in that: The display device comprises the organic electroluminescent device according to claim 8 or 9.

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