Compound containing boron and nitrogen and application thereof

Abstract

The invention provides a compound containing boron and nitrogen and application thereof.The compound containing boron and nitrogen has the structure shown in the formula I. The structure of the compound containing boron and nitrogen is designed, and the obtained compound containing boron and nitrogen has good light-emitting performance and can be used for preparing organic light-emitting devices. Particularly, as a luminescent layer material in the organic electroluminescent device, the compound can effectively reduce the driving voltage of the organic electroluminescent device and improve the current efficiency of the organic electroluminescent device.

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 application thereof. 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 present invention aims to provide a boron-nitrogen-containing compound and its application. The present invention designs the structure of the boron-nitrogen-containing compound to obtain a boron-nitrogen-containing compound with excellent performance, which is suitable for use as a light-emitting layer material in an organic electroluminescent device.

[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 or Formula II:

[0009]

[0010] The X, Y, and Z are independently selected from O, S, Se, The adjacent carbon atoms of R1 and R2 can be connected to form a ring by a single bond, and the adjacent carbon atoms of R3 and R4 can be connected to form a ring by a single bond;

[0011] The dotted line indicates that Y and Z may exist or not exist, and at least one of Y and Z exists;

[0012] R1, R2, R3, and R4 are independently selected from substituted or unsubstituted C1 to C 12 Alkyl, substituted or unsubstituted C6~C 30 Aromatic hydrocarbon or C3~C 30 An aromatic heterocyclic group;

[0013] Ar1 is selected from substituted or unsubstituted C1 to C 12 Alkyl, substituted or unsubstituted C6~C 30 aryl or substituted or unsubstituted C3~C 30 heteroaryl;

[0014] All hydrogen atoms in Formula I or Formula II may be independently substituted or unsubstituted by deuterium, F, CN, C1-C 12 Alkyl, substituted or unsubstituted C6~C 30 aryl or substituted or unsubstituted C3~C 30 is substituted with a heteroaryl group;

[0015] The substituents in the substituted groups are selected from deuterium, F, CN, C1-C 12 Alkyl, C6~C 30 Aryl or C3~C 30 The heteroaryl group.

[0016] In the present invention, the "non-existence" means that there is no connection at the location. The following examples are provided to exemplify the meaning of the sentence "wherein the dotted line indicates that Y and Z may exist or not exist, and at least one of Y and Z exists":

[0017] When Y exists and Z does not exist, the following structure is obtained:

[0018]

[0019] When Y does not exist and Z exists, the following structure is obtained:

[0020]

[0021] When Y and Z exist at the same time, the following structure is obtained:

[0022]

[0023] However, Y and Z cannot be absent at the same time, that is, the present invention does not include a structure having the following general formula:

[0024]

[0025] Preferably, the C1 to C 12 The alkyl group is selected from methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl, tert-pentyl, n-hexyl or cyclohexyl.

[0026] More preferably, the C1 to C 12 The alkyl group is selected from methyl, ethyl or tert-butyl.

[0027] Preferably, the C6~C 30 The aryl group is the general term for the monovalent group left after removing a hydrogen atom from the aromatic carbon of the aromatic hydrocarbon molecule; 30 The aryl group includes a monocyclic aryl group or a condensed ring aryl group.

[0028] Preferably, the C6~C 30 The aryl group of is selected from phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, indenyl, fluorenyl, perylenyl, phenanthryl, pyrenyl, fluoranthenyl, fluorenyl, spirobifluorenyl or triphenylenyl.

[0029] More preferably, the C6~C 30 The aryl group is selected from phenyl, biphenyl, naphthyl or terphenyl.

[0030] Preferably, the C3 to 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; 30 The heteroatom of the heteroaryl is selected from oxygen, sulfur, nitrogen or silicon; the C3~C 30 The heteroaryl group includes a monocyclic heteroaryl group or a condensed-ring heteroaryl group.

[0031] Preferably, the C3 to C 30 The heteroaryl group is selected from benzofuranyl, benzothiophenyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, diarylideneamine, benzofuranocarbazolyl, benzofuranothiophenyl or triazine.

[0032] More preferably, the C3 to C 30 The heteroaryl group is selected from dibenzofuranyl, dibenzothienyl or carbazolyl.

[0033] Preferably, X, Y, and Z are independently selected from O, S, Se, The wavy line represents the attachment site of the group.

[0034] Preferably, the boron-nitrogen-containing compound is selected from any one of compounds 1 to 128:

[0035]

[0036]

[0037]

[0038]

[0039]

[0040] 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. All structures based on the structure shown in Formula I or Formula II and in which X, Y, and Z meet the above-mentioned limiting conditions should be included.

[0041] 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.

[0042] 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, and the material of the organic layer comprises the boron-nitrogen-containing compound as described in the first aspect.

[0043] 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.

[0044] Furthermore, the light-emitting layer is prepared by a solution method.

[0045] In a third aspect, the present invention provides a display device, comprising the organic electroluminescent device as described in the second aspect.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] 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

[0048] 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 used to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0049] Synthesis Example 1

[0050] This embodiment provides a method for synthesizing compound 1, which is as follows:

[0051]

[0052] (1) Synthesis of intermediate 1-1

[0053] Under nitrogen protection, into a 500mL three-necked flask, add 200mL dry toluene, 0.1mol 3-bromobenzofuran, 0.1mol amine-1, 0.001mol Pd(dba)2 (bis(dibenzylideneacetonepalladium), 4g of 10% tri-tert-butylphosphine toluene solution (the amount of tri-tert-butylphosphine is 0.002mol) and 0.3mol sodium tert-butoxide, heat to reflux reaction for 12h, cool to room temperature, add water to separate, then wash the organic layer with water until neutral, dry with magnesium sulfate, filter to remove magnesium sulfate, concentrate to dryness, and crystallize with ethanol to obtain intermediate 1-1;

[0054] The intermediate 1-1 was subjected to mass spectrometry detection: the mass-to-charge ratio (m / z) was measured to be 466.2.

[0055] (2) Synthesis of Compound 1

[0056] Under nitrogen protection and oil bath heating, 200 mL of dry o-dichlorobenzene, 0.01 mol of intermediate 1-1, and 0.00 6 mol of anhydrous nickel chloride were added to a 500 mL three-necked flask, and the mixture was stirred evenly. The temperature was maintained at 20°C-25°C, and 20 mL of 1.0 M BBr3 dichloromethane solution (containing 0.02 mol of BBr3) was slowly added dropwise. After the addition, the temperature was slowly raised to 40°C for the oil bath to react for 2 h, and then the temperature was slowly raised to 100°C for the oil bath. During the process, the dichloromethane in the reaction system was distilled out, and then the oil bath was maintained at 100°C for reaction for 4 h, and then the temperature was raised to 140°C for reaction for 12 h, and then the mixture was cooled to room temperature, and 0.05 mol of N-ethyldiisopropylamine was slowly added to terminate the reaction; water was then added to separate the mixture, and the organic layer was washed with water until neutral, dried with magnesium sulfate, filtered to remove the magnesium sulfate, concentrated to dryness, and separated by silica gel column chromatography, eluted with petroleum ether: ethyl acetate = 20:1 (volume ratio) to obtain compound 1.

[0057] The obtained compound 1 was subjected to mass spectrometry detection: the mass-to-charge ratio (m / z) was measured to be 474.2.

[0058] Synthesis Example 2

[0059] This embodiment provides a method for synthesizing compound 2, which is as follows:

[0060]

[0061] Referring to the synthesis method of Synthesis Example 1, 3-bromobenzofuran in Synthesis Example 1 was replaced by 2-bromobenzofuran in an equal molar amount, and compound 2 was obtained while keeping other conditions unchanged.

[0062] Mass spectrometry detection was performed on compound 2: the mass spectrum m / z was measured to be 474.2.

[0063] Synthesis Example 3

[0064] This embodiment provides a method for synthesizing compound 3, which is as follows:

[0065]

[0066] Referring to the synthesis method of Synthesis Example 1, 3-bromobenzofuran in Synthesis Example 1 was replaced by an equal molar amount of 3-bromobenzothiophene, and other conditions remained unchanged to obtain Compound 3.

[0067] Mass spectrometry detection was performed on compound 3: the mass spectrum m / z was measured to be 490.1.

[0068] Synthesis Example 4

[0069] This embodiment provides a method for synthesizing compound 7, which is as follows:

[0070]

[0071] Referring to the synthesis method of Synthesis Example 3, amine-1 in Synthesis Example 3 is replaced by amine-2 in an equal molar amount, and compound 7 can be obtained while keeping other conditions unchanged.

[0072] Mass spectrometry detection was performed on compound 7: the mass spectrum m / z was measured to be 506.1.

[0073] Synthesis Example 5

[0074] This example provides a method for synthesizing compound 79, which is as follows:

[0075]

[0076] Referring to the synthesis method of Synthesis Example 3, amine-3 in Synthesis Example 3 is substituted for amine-1 with an equal molar amount, and other conditions remain unchanged to obtain compound 31.

[0077] Mass spectrometry detection was performed on compound 31: the mass spectrum m / z was measured to be 506.1.

[0078] Synthesis Example 6

[0079] This embodiment provides a method for synthesizing compound 35, which is as follows:

[0080]

[0081] Referring to the synthesis method of Synthesis Example 3, amine-1 in Synthesis Example 3 is replaced by amine-4 in an equal molar amount, and compound 35 can be obtained while keeping other conditions unchanged.

[0082] Compound 35 was subjected to mass spectrometry detection: the mass spectrum was measured to be m / z 516.2.

[0083] Synthesis Example 7

[0084] This example provides a method for synthesizing compound 90, which is as follows:

[0085]

[0086] (1) Synthesis of Intermediate 90-1

[0087] 0.1 mol of 3-tert-butyl-6-aminophenol, 0.1 mol of 2,4-dichlorofluorobenzene, 200 ml of DMF and 0.3 mol of potassium carbonate were added to a 500 ml reaction bottle, heated to 110 °C under nitrogen protection and kept for 12 hours. After cooling to room temperature, 200 ml of water and 200 ml of ethyl acetate were added, separated, organic dried and concentrated, and recrystallized with 100 ml of ethanol and 100 ml of n-heptane to obtain intermediate 90-1

[0088] The intermediate 90-1 was subjected to mass spectrometry detection: the mass spectrum was measured to be m / z 309.1.

[0089] (2) Synthesis of Intermediate 90-2

[0090] Under nitrogen protection, add 200 mL of dry toluene, 0.1 mol of intermediate 90-1, 0.001 mol of Pd(dba)2 (bis(dibenzylideneacetonepalladium), 4 g of 10% tri-tert-butylphosphine toluene solution (the amount of tri-tert-butylphosphine is 0.002 mol) and 0.3 mol of sodium tert-butoxide to a 500 mL three-necked flask, heat to reflux reaction for 12 h, cool to room temperature, add water to separate, then wash the organic layer with water until neutral, dry with magnesium sulfate, filter to remove magnesium sulfate, concentrate to dryness, and crystallize with ethanol to obtain intermediate 90-2;

[0091] The intermediate 90-1 was subjected to mass spectrometry detection: the mass spectrum was measured to be m / z 273.1.

[0092] (3) Synthesis of Intermediate 90-3

[0093] Under nitrogen protection, add 200 mL of dry toluene, 0.1 mol of intermediate 90-2, 0.1 mol of di(di-tert-butylphenyl)amine, 0.001 mol of Pd(dba)2 (bis(dibenzylideneacetonepalladium), 4 g of 10% tri-tert-butylphosphine toluene solution (the amount of tri-tert-butylphosphine is 0.002 mol) and 0.3 mol of sodium tert-butoxide to a 500 mL three-necked flask, heat to reflux for reaction for 12 h, cool to room temperature, add water to separate, then wash the organic layer with water until neutral, dry with magnesium sulfate, filter to remove magnesium sulfate, concentrate to dryness, and crystallize with ethanol to obtain intermediate 90-3;

[0094] The intermediate 90-3 was subjected to mass spectrometry detection: the mass spectrum m / z 518.3 was measured.

[0095] (4) Synthesis of Compound 90

[0096] Referring to the synthesis method of Synthesis Example 1, the amine-1 in Synthesis Example 1 is replaced by an equal molar amount of intermediate 90-3, and 3-bromobenzofuran is replaced by an equal molar amount of tert-butyl-3-bromobenzofuran, and other conditions remain unchanged to obtain compound 90.

[0097] Compound 90 was subjected to mass spectrometry detection: the mass spectrum was measured to be m / z 714.4.

[0098] Synthesis Example 8

[0099] This embodiment provides a method for synthesizing compound 94, which is as follows:

[0100]

[0101] Referring to the synthesis method of Synthesis Example 7, Compound 94 can be obtained by replacing 2,4-dichlorofluorobenzene in Synthesis Example 7 with an equal molar amount of 2,4-dichloro-6-tert-butylfluorobenzene and keeping other conditions unchanged.

[0102] Compound 94 was subjected to mass spectrometry detection: the mass spectrum was measured to be m / z 774.4.

[0103] Other compounds whose specific synthesis steps are not listed can be prepared by common knowledge in the art in combination with the above embodiments.

[0104] The specific structures of the compounds used in the following device examples and device comparative examples are shown below:

[0105]

[0106] 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 and BD-2 are selected as the doping material for the light-emitting layer in the organic electroluminescent device.

[0107] Device Example 1

[0108] 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 a solution method.

[0109] The structure of the organic electroluminescent device is:

[0110] ITO / HT (40 nm) / BH-1: Compound 1 (3%) / TPBI (30 nm) / LiF (0.5 nm) / Al (150 nm).

[0111] The preparation method of the organic electroluminescent device is as follows:

[0112] 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;

[0113] The glass substrate was placed in a vacuum chamber and evacuated to 1×10 -5 ~9×10 -3 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;

[0114] The glass substrate on which the hole transport layer has been evaporated is transferred to a glove box filled with nitrogen, and the light-emitting layer solution is spin-coated on the hole transport layer, wherein the light-emitting layer solution includes a solute and a solvent, wherein the solute includes BH-1 and 5% by mass of compound 1, and the solvent is 4-cyclohexylbenzene and chlorobenzene, wherein 4-cyclohexylbenzene:chlorobenzene=3:1 (volume ratio); the spin coating speed is 1000 rpm, and the time is 60 seconds, and then the glass substrate is heated at 80°C for 2 hours, and the solvent is removed in vacuo, and the thickness of the obtained light-emitting layer is 35 nm by adjusting the concentrations of BH-1 and compound 1 in the solvent.

[0115] The glass substrate on which the light-emitting layer has been spin-coated in the previous step is transferred into a vacuum chamber, and TPBI is vacuum-evaporated on the light-emitting layer as the electron transport layer of the device. The evaporation rate is 0.1 nm / s, and the total evaporation film thickness is 30 nm;

[0116] 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.

[0117] The brightness, driving voltage and current efficiency of the prepared organic electroluminescent device were measured.

[0118] Device Examples 2 to 10

[0119] Device Examples 2 to 10 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 1 for details), and other conditions are the same as those of Device Example 1.

[0120] Device Comparison Examples 1 to 2

[0121] Device Comparative Examples 1 to 2 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 1 for details), and other conditions are the same as those of Device Example 1.

[0122] Performance Testing

[0123] 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 value of the time (based on the test data of BD-1). The test results of the performance of the organic electroluminescent device are shown in Table 1 below.

[0124] Table 1

[0125]

[0126] 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.

[0127] 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 or Formula II: The X, Y, and Z are independently selected from O, S, Se, The adjacent carbon atoms of R1 and R2 can be connected to form a ring by a single bond, and the adjacent carbon atoms of R3 and R4 can be connected to form a ring by a single bond; The dotted line indicates that Y and Z may exist or not exist, and at least one of Y and Z exists; R1, R2, R3, and R4 are independently selected from substituted or unsubstituted C1 to C 12 Alkyl, substituted or unsubstituted C6~C 30 Aromatic hydrocarbon or C3~C 30 An aromatic heterocyclic group; Ar1 is selected from substituted or unsubstituted C1 to C 12 Alkyl, substituted or unsubstituted C6~C 30 aryl or substituted or unsubstituted C3~C 30 heteroaryl; All hydrogen atoms in Formula I or Formula II may be independently substituted or unsubstituted by deuterium, F, CN, C1-C 12 Alkyl, substituted or unsubstituted C6~C 30 aryl or substituted or unsubstituted C3~C 30 is substituted with a heteroaryl group; The substituents in the substituted groups are selected from deuterium, F, CN, C1-C 12 Alkyl, C6~C 30 Aryl or C3~C 30 The heteroaryl group.

2. The boron-nitrogen-containing compound according to claim 1, 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 or tert-butyl.

3. The boron-nitrogen-containing compound according to claim 1 or 2, characterized in that C6~C 30 The aryl group includes a monocyclic aryl group or a condensed ring aryl group; 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, naphthyl or terphenyl.

4. The boron-nitrogen-containing compound according to any one of claims 1 to 3, characterized in that C3~C 30 The heteroatoms of the heteroaryl group are selected from oxygen, sulfur, nitrogen or silicon; Preferably, the C3 to C 30 The heteroaryl group includes a monocyclic heteroaryl group or a condensed-ring heteroaryl group; Preferably, the C3 to C 30 The heteroaryl group is selected from benzofuranyl, benzothiophenyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, diarylideneamine, benzofuranocarbazolyl, benzofuranothiophenyl or triazine; More preferably, the C3 to C 30 The heteroaryl group is selected from dibenzofuranyl, dibenzothienyl or carbazolyl.

5. The boron-nitrogen-containing compound according to any one of claims 1 to 4, characterized in that X, Y, and Z are independently selected from O, S, Se, 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 128:

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, and the material of the organic layer comprises the boron-nitrogen-containing compound as claimed in any one of claims 1 to 6.

9. The organic electroluminescent device according to claim 8, characterized in that: The organic layer comprises a light-emitting layer, and a material of the light-emitting layer comprises the boron-nitrogen-containing compound as claimed in any one of claims 1 to 6.

10. A display device, characterized in that: The display device comprises the organic electroluminescent device according to any one of claims 7 to 9.

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