Fluorenone derivative, light extraction material and application thereof

Abstract

The invention discloses a fluorenone derivative, a light extraction material and application thereof, and belongs to the technical field of display. The fluorenone derivative comprises fluorenone and a substituent group connected to at least one benzene ring in the fluorenone, and the chemical general formula of the substituent group is as follows: # imgabs0 # L1 and L2 are selected from any one of a single bond, an arylene group of C6-C36 and a heteroarylene group of C2-C36. R1 and R2 are respectively and independently selected from any one of hydrogen, deuterium, alkyl of C1-C12, alkenyl of C2-C12, cycloalkyl of C3-C12, heterocycloalkyl of C2-C12, alkoxy of C1-C12, aryl of C6-C36, heteroaryl of C2-C36, Ar1, Ar2, Ar3, Ar4, Ar5 and Ar6. The fluorenone derivative is suitable for preparing a light extraction layer with high refractive index and strong stability, and the light extraction efficiency of the light extraction layer is improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to fluorenone derivatives, light extraction materials and applications thereof. Background Art

[0002] Organic Light Emission Diodes (OLED) are widely used in the field of lighting and display. OLED devices include a light-emitting functional layer and a cathode and an anode stacked on both sides of the light-emitting functional layer. By applying an electric field between the cathode and the anode, electrons are injected from the cathode and holes are injected from the anode. The electrons and holes recombine in the light-emitting functional layer and realize OLED electroluminescence.

[0003] Due to the difference in refractive index between different media, light is easily lost at the interface when it is transmitted between different media. Therefore, a light extraction (Capping Layer, CPL) layer is usually set on the side of the cathode away from the light-emitting functional layer. The CPL layer has a high refractive index, so that the light confined inside the OLED device can be emitted to the outside, which is manifested as a higher light extraction efficiency.

[0004] However, the refractive index of the currently known light extraction layer still needs to be improved. Summary of the invention

[0005] In view of this, the present application provides a fluorenone derivative, a light extraction material and its application, which can solve the technical problems existing in the related technology.

[0006] Specifically, the following technical solutions are included:

[0007] In one aspect, a fluorenone derivative is provided, the fluorenone derivative comprising: fluorenone and a substituent group connected to at least one benzene ring in the fluorenone, the chemical formula of the substituent group is as follows:

[0008]

[0009] Wherein, L1 and L2 are each independently selected from any one of a single bond, a substituted or unsubstituted C6-C36 arylene group, and a substituted or unsubstituted C2-C36 heteroarylene group;

[0010] R1 and R2 are each independently selected from hydrogen, deuterium, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted C2-C12 heterocycloalkyl, substituted or unsubstituted C1-C12 alkoxy, substituted or unsubstituted C6-C36 aryl, substituted or unsubstituted C2-C36 heteroaryl, any one of Ar1, Ar2, Ar3, Ar4, Ar5 and Ar6;

[0011] Among them, the chemical formulas of Ar1, Ar2, Ar3, Ar4, Ar5 and Ar6 are as follows:

[0012]

[0013] Multiple Zs are each independently C(r1) or N atom, and multiple r1s are each independently any one of hydrogen, deuterium, cyano, nitro, halogen atom, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted C2-C12 heterocycloalkyl, substituted or unsubstituted C1-C12 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C2-C30 heteroaryl;

[0014] X1 and Y are selected from O atom, S atom, C(r2r3) or N(r4);

[0015] r2 and r3 are each independently selected from any one of hydrogen, deuterium, cyano, nitro, a halogen atom, a substituted or unsubstituted C1-C12 alkyl group, a substituted or unsubstituted C2-C12 alkenyl group, a substituted or unsubstituted C3-C12 cycloalkyl group, a substituted or unsubstituted C2-C12 heterocycloalkyl group, a substituted or unsubstituted C1-C12 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, and a substituted or unsubstituted C2-C30 heteroaryl group;

[0016] r4 is selected from any one of hydrogen, deuterium, cyano, nitro, a halogen atom, a substituted or unsubstituted C1-C12 alkyl group, a substituted or unsubstituted C2-C12 alkenyl group, a substituted or unsubstituted C3-C12 cycloalkyl group, a substituted or unsubstituted C2-C12 heterocycloalkyl group, a substituted or unsubstituted C1-C12 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, and a substituted or unsubstituted C2-C30 heteroaryl group;

[0017] Ring A and Ring B are each independently selected from any one of a substituted or unsubstituted benzene ring, a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted anthracene ring, and a substituted or unsubstituted phenanthrene ring.

[0018] In some possible implementations, the general chemical formula of the fluorenone derivative is as follows:

[0019]

[0020] In some possible implementations, the general chemical formula of the fluorenone derivative is as follows:

[0021]

[0022] In some possible implementations, the chemical formula of Ar1 is as shown in any of the following:

[0023]

[0024]

[0025] In some possible implementations, the chemical formula of Ar2 is as shown in any of the following:

[0026]

[0027] In some possible implementations, the chemical formula of Ar3 is as shown in any of the following:

[0028]

[0029] In some possible implementations, the chemical formula of Ar4 is as shown in any of the following:

[0030]

[0031] In some possible implementations, the chemical formula of Ar5 is as shown in any of the following:

[0032]

[0033] In some possible implementations, the chemical formula of Ar6 is as shown in any of the following:

[0034]

[0035]

[0036]

[0037]

[0038] In some possible implementations, L1 and L2 are each independently selected from a single bond or a phenylene group;

[0039] R1 is selected from one of Ar1, Ar2, Ar3, Ar4, Ar5, and Ar6, and R2 is selected from another one of Ar1, Ar2, Ar3, Ar4, Ar5, and Ar6.

[0040] On the other hand, a method for preparing any of the above-mentioned fluorenone derivatives is provided, the preparation method comprising:

[0041] Providing a fluorenone halide and an amine compound corresponding to the substituent group;

[0042] In the presence of a protective atmosphere and a catalyst, the fluorenone halides and the amine compounds corresponding to the substituent groups undergo a nucleophilic substitution reaction to prepare the fluorenone derivatives.

[0043] In some possible implementations, the catalyst is a palladium catalyst.

[0044] On the other hand, a light extraction material is provided, wherein the light extraction material comprises any of the above-mentioned fluorenone derivatives.

[0045] In some possible implementations, the mass percentage of the fluorenone derivative is 100%.

[0046] In some possible implementations, the light extraction material further includes an auxiliary agent, and the auxiliary agent is selected from at least one of a material having a refractive index lower than that of a fluorenone derivative, a scattering agent, and a light stabilizer.

[0047] In some possible implementations, the refractive index of the light extraction material within the wavelength range of 460 nm-620 nm is greater than 2.

[0048] In some possible implementations, the glass transition temperature of the light extraction material is greater than or equal to 130°C.

[0049] On the other hand, an organic electroluminescent device is provided, comprising an anode, a light-emitting functional layer, a cathode and a light extraction layer which are sequentially stacked, wherein the light extraction layer is made of any of the above-mentioned light extraction materials.

[0050] In some possible implementations, the light-emitting functional layer includes a hole transport unit, a light-emitting functional layer and an electron transport unit, and the hole transport unit, the light-emitting functional layer and the electron transport unit are sequentially stacked in a direction from the anode to the cathode;

[0051] Wherein, the hole transport unit includes at least one of a hole injection layer, a hole transport layer, and an electron blocking layer;

[0052] The electron transport unit includes at least one of a hole blocking layer, an electron transport layer, and an electron injection layer.

[0053] In yet another aspect, a display device is provided, comprising any one of the organic electroluminescent devices described above.

[0054] The beneficial effects of the technical solution provided by the embodiments of the present application include at least:

[0055] The fluorenone derivative provided in the embodiment of the present application includes a fluorenone group in a conjugated fused ring structure, which has certain light refractive properties and good rigidity, ensuring the basic optical properties and good thermal stability of the fluorenone derivative. Further, fluorenone is combined with an amino substituent having a specific chemical structure. Such amino substituents, as side chains, have more lone pairs of electrons, so that the molecules of the fluorenone derivatives formed by cooperating with the fluorenone group have a larger polarizability, thereby presenting a high refractive index. Thus, the fluorenone derivative can be used to prepare a light extraction layer of an organic electroluminescent device, and the light extraction layer is given a higher refractive index and stronger stability, so as to obtain a higher light extraction efficiency, which is conducive to improving the device efficiency and life of the organic electroluminescent device. DETAILED DESCRIPTION

[0056] The technical solutions in the embodiments of the present application are described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0057] In view of the technical problem that the refractive index of the light extraction layer in the current OLED device still needs to be improved, the embodiments of the present application provide a new type of fluorenone derivative, which can be used to prepare the light extraction layer of the OLED device and make it have a higher refractive index.

[0058] The fluorenone derivative provided in the embodiment of the present application includes: fluorenone and a substituent group connected to at least one benzene ring in fluorenone, and the chemical formula of the substituent group is as follows:

[0059]

[0060] Wherein, L1 and L2 are independently selected from any one of a single bond, a substituted or unsubstituted C6-C36 arylene group, and a substituted or unsubstituted C2-C36 heteroarylene group. R1 and R2 are independently selected from any one of hydrogen, deuterium, a substituted or unsubstituted C1-C12 alkyl group, a substituted or unsubstituted C2-C12 alkenyl group, a substituted or unsubstituted C3-C12 cycloalkyl group, a substituted or unsubstituted C2-C12 heterocycloalkyl group, a substituted or unsubstituted C1-C12 alkoxy group, a substituted or unsubstituted C6-C36 aryl group, a substituted or unsubstituted C2-C36 heteroaryl group, Ar1, Ar2, Ar3, Ar4, Ar5, and Ar6.

[0061] The chemical formulas of Ar1, Ar2, Ar3, Ar4, Ar5 and Ar6 are as follows:

[0062]

[0063] Multiple Zs are each independently a C(r1) or N atom, and multiple r1s are each independently a hydrogen atom, a deuterium, a cyano group, a nitro group, a halogen atom, a substituted or unsubstituted C1-C12 alkyl group, a substituted or unsubstituted C2-C12 alkenyl group, a substituted or unsubstituted C3-C12 cycloalkyl group, a substituted or unsubstituted C2-C12 heterocycloalkyl group, a substituted or unsubstituted C1-C12 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, or a substituted or unsubstituted C2-C30 heteroaryl group.

[0064] X1, Y are selected from O atoms, S atoms, C (r2r3) or N (r4); r2, r3 are each independently selected from hydrogen, deuterium, cyano, nitro, halogen atoms, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted C2-C12 heterocycloalkyl, substituted or unsubstituted C1-C12 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted R4 is selected from any one of hydrogen, deuterium, cyano, nitro, halogen atoms, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted C2-C12 heterocycloalkyl, substituted or unsubstituted C1-C12 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C2-C30 heteroaryl. Exemplarily, R2 and R3 can exist independently of each other or be connected to form a ring.

[0065] Ring A and Ring B are each independently selected from any one of a substituted or unsubstituted benzene ring, a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted anthracene ring, and a substituted or unsubstituted phenanthrene ring.

[0066] For the above-mentioned anthracene derivatives, the arylene group involved can be a subunit of the following aromatic groups: phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthryl, peryl, fluoranthenyl, triphenylene, phenanthrenyl, pyrenyl, tetraphenyl, pentaphenyl, fluorenyl, indenyl, acenaphthene, benzofluorenyl, spirofluorenyl, etc.

[0067] Some examples of the aryl groups involved can be shown as follows: phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthrenyl, peryl, fluoranthenyl, triphenylene, phenanthrenyl, pyrenyl, tetracenyl, pentacene, fluorenyl, indenyl, acenaphthyl, benzofluorenyl, spirofluorenyl, etc.

[0068] The heteroatoms contained in the heteroaryl radical involved may be O, S, N, etc., and the heteroaryl radical may be a subunit of the following heteroaryl radicals: benzofuranyl, naphthofuranyl, phenanthrofuranyl, dibenzofuranyl, benzodibenzofuranyl, benzothiophenyl, naphthiophenyl, phenanthrothiophenyl, dibenzothiophenyl, benzodibenzothiophenyl, indolyl, naphthioindolyl, carbazolyl, benzocarbazolyl, benzodisulfide, dihydroisobenzofuranyl, dihydrobenzofuranyl, dihydrobenzothiophenyl, dihydroisobenzothiophenyl, phenoxazinyl, phenothiazinyl, pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, quinolyl, etc.

[0069] Some examples of the heteroaryl groups involved can be shown as follows: benzofuranyl, naphthofuranyl, phenanthrofuranyl, dibenzofuranyl, benzodibenzofuranyl, benzothiophenyl, naphthiophenyl, phenanthrothiophenyl, dibenzothiophenyl, benzodibenzothiophenyl, indolyl, naphthioindolyl, carbazolyl, benzocarbazolyl, benzodisulfide, dihydroisobenzofuranyl, dihydrobenzofuranyl, dihydrobenzothiophenyl, dihydroisobenzothiophenyl, phenoxazinyl, phenothiazinyl, pyridinyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, quinolinyl, etc.

[0070] The alkyl group involved can be methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, n-pentyl, isopentyl, neopentyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methylpentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl, octyl, etc.

[0071] The alkenyl group involved can be vinyl, propenyl-1-yl, propenyl-2-yl, propenyl-3-yl, buten-1-yl, buten-2-yl, buten-3-yl, buten-4-yl, 1-methylpropen-1-yl, 2-methylpropen-1-yl, 1-ethyl-ethen-1-yl, 2-methyl-propen-3-yl, buta-1,3-dienyl, buta-1,2-dienyl, buta-1,2-dien-4-yl, pentenyl, hexenyl, heptenyl, octenyl, etc.

[0072] The cycloalkyl group involved may be cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, norbornyl, etc.

[0073] The heterocycloalkyl involved refers to an alkyl skeleton containing one or more heteroatoms, and the heteroatoms may be oxygen atoms, nitrogen atoms, sulfur atoms, etc. Some examples of heterocycloalkyl may be methoxymethyl, ethoxyethyl, propoxypropyl, methoxyethyl, etc.

[0074] The alkoxy group referred to may be methoxy, ethoxy, propoxy, butoxy, pentoxy, or the like.

[0075] The fluorenone derivative provided in the embodiment of the present application includes a fluorenone group in a conjugated fused ring structure, which has certain light refractive properties and good rigidity, ensuring the basic optical properties and good thermal stability of the fluorenone derivative. Further, fluorenone is combined with an amino substituent having a specific chemical structure. Such amino substituents, as side chains, have more lone pairs of electrons, so that the molecules of the fluorenone derivatives formed by cooperating with the fluorenone group have a larger polarizability, thereby presenting a high refractive index. Thus, the fluorenone derivative can be used to prepare a light extraction layer of an organic electroluminescent device, and the light extraction layer is given a higher refractive index and stronger stability, so as to obtain a higher light extraction efficiency, which is conducive to improving the device efficiency and life of the organic electroluminescent device.

[0076] In the embodiments of the present application, the substituent group can be connected to any one of the two benzene rings of fluorenone, or can be connected to both of the benzene rings of fluorenone at the same time, as illustrated below.

[0077] As an example, for a fluorenone derivative in the form of fluorenone + monoaromatic amine, the chemical formula of the fluorenone derivative is as follows:

[0078]

[0079] In the above example, the substituent group is connected to the benzene ring on the right side of fluorenone. In fact, the fluorenone derivatives formed by the substituent group connected to the benzene ring on the right side of fluorenone and the substituent group connected to the benzene ring on the left side of fluorenone are equivalent.

[0080] As another example, for a fluorenone derivative in the form of fluorenone + biphenylamine, the chemical formula of the fluorenone derivative is as follows:

[0081]

[0082] For any of the above-mentioned fluorenone derivatives, in some examples, L1 and L2 are independently selected from a single bond or a phenylene group, and the two can be the same (for example, both are single bonds or both are phenylene groups), or different (for example, one is a single bond and the other is a phenylene group). And, R1 and R2 are independently selected from any one of Ar1, Ar2, Ar3, Ar4, Ar5, and Ar6 to achieve the purpose of optimizing the above-mentioned effects.

[0083] For example, R1 and R2 are different, that is, R1 is selected from one of Ar1, Ar2, Ar3, Ar4, Ar5, Ar6, and R2 is selected from another of Ar1, Ar2, Ar3, Ar4, Ar5, Ar6. Different aromatic groups have different electron cloud distributions and degrees of conjugation. When they are connected to the N atom, the electron cloud distribution of the molecule as a whole becomes more uneven, thereby increasing the polarizability of the molecule. The greater the molecular polarizability, the greater the degree of deformation of the electron cloud under the action of the electromagnetic field, and the stronger the ability to refract light, thereby increasing the refractive index of the material.

[0084] Some chemical formulas of Ar1 applicable to the fluorenone derivatives involved in the embodiments of the present application are shown in any of the following:

[0085]

[0086] Some chemical formulas of Ar2 applicable to the fluorenone derivatives involved in the embodiments of the present application are shown in any of the following:

[0087]

[0088] Some chemical formulas of Ar3 applicable to the fluorenone derivatives involved in the embodiments of the present application are shown in any of the following:

[0089]

[0090] Some chemical formulas of Ar4 applicable to the fluorenone derivatives involved in the embodiments of the present application are shown in any of the following:

[0091]

[0092] Some chemical formulas of Ar5 applicable to the fluorenone derivatives involved in the embodiments of the present application are shown in any of the following:

[0093]

[0094] Some chemical formulas of Ar6 applicable to the fluorenone derivatives involved in the embodiments of the present application are shown in any of the following:

[0095]

[0096]

[0097]

[0098] In combination with the above schemes of fluorenone derivatives, some examples of fluorenone derivatives can be shown as follows:

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[0321] On the other hand, an embodiment of the present application provides a method for preparing the above-mentioned fluorenone derivatives, which comprises: providing a halide of fluorenone and an amine compound corresponding to the substituent group; in the presence of a protective atmosphere and a catalyst, allowing the halide of fluorenone to undergo a nucleophilic substitution reaction with the amine compound corresponding to the substituent group to prepare a fluorenone derivative.

[0322] According to the chemical structure of the anthracene derivative, an amine compound corresponding to the substituent group is designed, wherein the amine compound can be obtained by purchasing a known compound product or prepared by itself. For example, when preparing the amine compound, the amine compound can be synthesized by an intermediate compound containing R1 and an intermediate compound containing R2.

[0323] The catalyst suitable for the preparation method of the fluorenone derivatives of the embodiment of the present application is a palladium catalyst, which exhibits high selectivity, wide substrate adaptability, mild reaction conditions and efficient catalytic activity in nucleophilic substitution reactions. By changing the reaction conditions such as the ligand, reaction solvent, temperature, and base of the palladium catalyst, the activity and selectivity of the reaction can be finely controlled to meet different synthesis requirements.

[0324] On the other hand, the embodiment of the present application further provides a light extraction material, which includes any of the above-mentioned fluorenone derivatives. The light extraction material provided by the embodiment of the present application has all the advantages of the fluorenone derivatives.

[0325] In some examples, the mass percentage of the fluorenone derivative in the light extraction material is 100%.

[0326] In other examples, the light extraction material includes a fluorenone derivative and an additive, and the amount of the additive added is adaptively determined according to actual needs. For example, the mass percentage of the additive in the light extraction material may be 0.5%-10%, and further may be 0.5%-5%.

[0327] For example, the auxiliary agent can be a low refractive index material (nano-silica, etc.) with a refractive index lower than that of the fluorenone derivative. The low refractive index material cooperates with the high refractive index fluorenone derivative to form a refractive index gradient to reduce total internal reflection, thereby improving light extraction efficiency.

[0328] For example, the auxiliary agent may also be a scattering agent (such as nano titanium dioxide, nano zinc oxide, etc.), which changes the propagation direction of light by scattering light, so that more light can be taken out of the OLED device, thereby improving the light extraction efficiency.

[0329] For example, the auxiliary agent can also be a light stabilizer (such as a hindered amine light stabilizer), which can absorb or quench excited molecules to prevent degradation and photooxidation of the polymer chain of the fluorenone derivative, thereby maintaining the optical properties and stability of the light extraction layer.

[0330] Based on the use of the fluorenone derivative provided in the embodiment of the present application, the refractive index of the light extraction material in the wavelength range of 460nm-620nm is greater than 2, showing an excellent light refraction effect. In addition, the glass transition temperature of the light extraction material is greater than or equal to 130°C, showing excellent thermal stability.

[0331] On the other hand, the embodiment of the present application also provides an organic electroluminescent device, wherein the organic electroluminescent device comprises an anode, a light-emitting functional layer, a cathode and a light extraction layer which are stacked in sequence, and the light extraction layer adopts any of the above-mentioned light extraction materials. The organic electroluminescent device provided by the embodiment of the present application has all the advantages of the fluorenone derivative, so that it has higher light extraction efficiency and device stability.

[0332] For example, the light-emitting functional layer includes a hole transport unit, a light-emitting functional layer and an electron transport unit, and the hole transport unit, the light-emitting functional layer and the electron transport unit are stacked in sequence from the anode to the cathode. Among them, the hole transport unit includes at least one of a hole injection layer, a hole transport layer and an electron blocking layer; the electron transport unit includes at least one of a hole blocking layer, an electron transport layer and an electron injection layer.

[0333] In some examples (1), the hole transport unit includes a hole transport layer, wherein the anode, the hole transport layer, and the light-emitting functional layer are stacked in sequence.

[0334] In some examples (2), the hole transport unit includes a hole injection layer and a hole transport layer, wherein the anode, the hole injection layer, the hole transport layer, and the light-emitting functional layer are stacked in sequence.

[0335] In some examples (3), the hole transport unit includes a hole transport layer and an electron blocking layer, wherein the anode, the hole transport layer, the electron blocking layer, and the light-emitting functional layer are stacked in sequence.

[0336] In some examples (4), the hole transport region includes a hole transport layer, an electron blocking layer and a hole injection layer, wherein the anode, the hole injection layer, the hole transport layer, the electron blocking layer and the light-emitting functional layer are stacked in sequence.

[0337] In some examples (5), the electron transport region includes an electron transport layer, wherein the cathode, the electron transport layer, and the light-emitting functional layer are stacked in sequence.

[0338] In some examples (6), the electron transport region includes an electron transport layer and an electron injection layer, wherein the cathode, the electron injection layer, the electron transport layer, and the light-emitting functional layer are stacked in sequence.

[0339] In some examples (7), the electron transport region includes an electron transport layer and a hole blocking layer, wherein the cathode, the electron transport layer, the hole blocking layer, and the light-emitting functional layer are stacked in sequence.

[0340] In some examples (8), the electron transport region includes an electron transport layer, a hole blocking layer, and an electron injection layer, wherein the cathode, the electron injection layer, the electron transport layer, the hole blocking layer, and the light-emitting functional layer are stacked in sequence.

[0341] The hole transport unit, the electron transport unit, the anode and the cathode may all be made of currently known related materials, which will not be described in detail here.

[0342] For example, the hole injection layer includes but is not limited to: inorganic oxides, p-type dopants of strong electron-withdrawing systems and dopants of hole transport materials, such as hexacyanohexaazatriphenylene, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), 1,2,3-tris[(cyano)(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane, etc.

[0343] The hole transport material / electron blocking layer includes, but is not limited to, aromatic amines having hole transport properties and dimethylfluorene or carbazole materials and their derivatives.

[0344] The light-emitting layer is selected according to the actual light-emitting requirements. Taking the blue light-emitting material as an example, it can be a pyrene derivative, anthracene derivative, fluorene derivative, perylene derivative, amine derivative, etc.

[0345] The hole blocking layer / electron transport layer includes but is not limited to: aromatic heterocyclic compounds, which can be selected from but not limited to at least one of benzimidazole, triazine, pyrimidine, pyridine, pyrazine, quinoxaline, quinoline, diazole, diazaphosphine, phosphine oxide, aromatic ketone, lactam, borane compounds and their derivatives.

[0346] The electron injection layer is generally an alkali metal or a metal, such as LiF, Yb, Mg, Ca, or a compound thereof.

[0347] On the other hand, an embodiment of the present application further provides a display device, which includes any one of the organic electroluminescent devices mentioned above.

[0348] The display device provided in the embodiment of the present application has all the advantages of an organic electroluminescent device. Exemplarily, the display device includes but is not limited to: OLED TVs, tablet computers, car displays, MP3 players, smart watches, fitness bracelets, virtual reality (VR) helmets, augmented reality (AR) glasses, etc.

[0349] The exemplary embodiments of the present application will be described in more detail below. Although the exemplary embodiments of the present application are described below, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. The specific techniques or conditions not specified in the embodiments are carried out according to the techniques or conditions described in the documents in this area or according to the product specification. The reagents used or the instruments not specified in the manufacturers are all conventional products that can be obtained commercially.

[0350] Synthesis example E1:

[0351]

[0352] Add toluene solvent to the bottle, then add 1.05eq of compound A1 and 1eq of compound A2 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of palladium acetate, and 0.02eq of X-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, and dry in a vacuum drying oven for 3h to obtain a solid intermediate 1.

[0353]

[0354] Add toluene solvent to the bottle, then add compound A3 1eq, intermediate 1 1.1eq in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add sodium tert-butoxide 1.5eq, Pd2(dba)3 0.01eq, S-Phos 0.02eq. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, let stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, dry in a vacuum oven for 3h to obtain a solid, and sublime the solid to obtain compound E1.

[0355] Mass spectrum m / z: 590.68, element content (%): C42H26N2O2, C, 85.40; H, 4.44; O, 5.42; N, 4.74.

[0356] 1H NMR (300MHz, DMSO): 8.43-8.44(2H),8.34(1H),8.09(1H),8.06(1H),7.99(1H),7.68(1H),7.63 -7.64(5H),7.6(1H),7.55-7.57(5H),7.37-7.38(5H),7.33(1H),7.21(1H),6.56(1H).

[0357] Synthesis Example E2:

[0358]

[0359] Add toluene solvent to the bottle, then add 1.05eq of compound A1 and 1eq of compound A4 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of palladium acetate, and 0.02eq of X-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, and dry in a vacuum oven for 3h to obtain a solid intermediate 2.

[0360]

[0361] Add toluene solvent to the bottle, then add 1eq of compound A3 and 1.1eq of intermediate 2 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of Pd2(dba)3, and 0.02eq of S-Phos. Fill with nitrogen again and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain a filtrate. After concentration, heat, add a small amount of ethanol, let stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, dry in a vacuum drying oven for 3h to obtain a solid, and sublime the solid to obtain compound E2;

[0362] Mass spectrum m / z: 590.68, element content (%): C42H26N2O2, C, 85.40; H, 4.44; O, 5.42; N, 4.74.

[0363] 1H NMR (300MHz, DMSO): 8.34-8.44(2H),8.09(1H),8.06(1H),7.99(1H),7.73-7. 74(4H),7.68(1H),7.63-7.64(3H),7.6(1H),7.55-7.57(5H),7.37-7.38(7H).

[0364] Synthesis Example E3:

[0365]

[0366] Add toluene solvent to the bottle, then add 1.05eq of compound A1 and 1eq of compound A5 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of palladium acetate, and 0.02eq of X-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, and dry in a vacuum drying oven for 3h to obtain a solid intermediate 3.

[0367]

[0368] Add toluene solvent to the bottle, then add compound A3 1eq, intermediate 3 1.1eq in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add sodium tert-butoxide 1.5eq, Pd2(dba)3 0.01eq, S-Phos 0.02eq. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, dry in a vacuum oven for 3h to obtain a solid, and sublime the solid to obtain compound E3.

[0369] Mass spectrum m / z: 599.73, element content (%): C45H29NO, C, 90.12; H, 4.87; O, 2.67; N, 2.34.

[0370] 1H NMR (300MHz, DMSO): 8.44(1H), 8.34(1H), 8.09(2H), 8.06(2H), 7.99(2H), 7.68(1H), 7.63-7.64(4H), 7.6(2H), 7.55-7.57(8H), 7.37-7.38(6H).

[0371] Synthesis example E4:

[0372]

[0373] Add toluene solvent to the bottle, then add 1.05eq of compound A6 and 1eq of compound A4 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of palladium acetate, and 0.02eq of X-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, and dry in a vacuum drying oven for 3h to obtain a solid intermediate 4.

[0374]

[0375] Add toluene solvent to the bottle, then add 1eq of compound A3 and 1.1eq of intermediate 4 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of Pd2(dba)3, and 0.02eq of S-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, dry in a vacuum drying oven for 3h to obtain a solid, and sublime the solid to obtain compound E4.

[0376] Mass spectrum m / z: 581.63, element content (%): C39H23N3O3, C, 80.54; H, 3.99; O, 8.25; N, 7.22.

[0377] 1H NMR (300MHz, DMSO): 8.44(1H), 8.34(1H), 7.73-7.74(8H), 7.68(1H), 7.63-7.64(2H), 7.56-7.57(2H), 7.37-7.38(8H).

[0378] Synthesis example E5:

[0379]

[0380] Add toluene solvent to the bottle, then add 1.05eq of compound A7 and 1eq of compound A2 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of palladium acetate, and 0.02eq of X-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, and dry in a vacuum drying oven for 3h to obtain a solid intermediate 5.

[0381]

[0382] Add toluene solvent to the bottle, then add compound A3 1eq, intermediate 5 1.1eq in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add sodium tert-butoxide 1.5eq, Pd2(dba)3 0.01eq, S-Phos 0.02eq. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, dry in a vacuum oven for 3h to obtain a solid, and sublime the solid to obtain compound E5.

[0383] Mass spectrum m / z: 581.63, element content (%): C39H23N3O3, C, 80.54; H, 3.99; O, 8.25; N, 7.22; S, 4.32.

[0384] 1H NMR (300MHz, DMSO): 8.43-8.44(3H), 8.34(1H), 7.68(1H), 7.63-7.64(6H), 7.56-7.57(2H), 7.37(4H), 7.33(2H), 7.21(2H), 6.56(2H).

[0385] Synthesis Example E6:

[0386]

[0387] Add toluene solvent to the bottle, then add 1eq of compound A8 and 2.1eq of intermediate 1 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of Pd2(dba)3, and 0.02eq of S-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, let stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, dry in a vacuum drying oven for 3h to obtain a solid, and sublime the solid to obtain compound E6.

[0388] Mass spectrum m / z: 1001.16, element content (%): C71H44N4O3, C, 85.18; H, 4.43; O, 4.79; N, 5.60.

[0389] 1H NMR (300MHz, DMSO): 8.43(2H),8.09(2H),8.06(2H),7.99(2H),7.63-7.64(8H) ,7.6(2H),7.55-7.57(10H),7.37-7.38(10H),7.33(2H),7.21(2H),6.56(2H).

[0390] Synthesis Example E7:

[0391]

[0392] Add toluene solvent to the bottle, then add 1.05eq of compound A9 and 1eq of compound A2 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of palladium acetate, and 0.02eq of X-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, and dry in a vacuum drying oven for 3h to obtain a solid intermediate 7.

[0393]

[0394] Add toluene solvent to the bottle, then add 1eq of compound A3 and 1.1eq of intermediate 7 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of Pd2(dba)3, and 0.02eq of S-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain a filtrate. After concentration, heat, add a small amount of ethanol, let stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, dry in a vacuum oven for 3h to obtain a solid, and sublime the solid to obtain compound E7.

[0395] Mass spectrum m / z: 604.66, element content (%): C42H24N2O3, C, 83.43; H, 4.00; O, 7.94; N, 4.63.

[0396] 1H NMR (300MHz, DMSO): 8.43-8.44(2H),8.34(1H),8.28(1H),8.22(1H),8.11(1H),7.75(1H),7.68-7.69(2H), 7.63-7.64(4H),7.56-7.57(3H),7.49(1H),7.42(1H),7.37(2H),7.33(1H),7.21(1H),6.97(1H),6.56(1H).

[0397] Synthesis example E8:

[0398]

[0399] Add toluene solvent to the bottle, then add 1.05eq of compound A10 and 1eq of compound A2 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of palladium acetate, and 0.02eq of X-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, and dry in a vacuum oven for 3h to obtain a solid intermediate 8.

[0400]

[0401] Add toluene solvent to the bottle, then add 1eq of compound A3 and 1.1eq of intermediate 8 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of Pd2(dba)3, and 0.02eq of S-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain a filtrate. After concentration, heat, add a small amount of ethanol, let stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, dry in a vacuum drying oven for 3h to obtain a solid, and sublime the solid to obtain compound E8.

[0402] Mass spectrum m / z: 604.66, element content (%): C42H24N2O3, C, 83.43; H, 4.00; O, 7.94; N, 4.63.

[0403] 1H NMR (300MHz, DMSO): 8.43-8.44(2H),8.34(1H),8.28(1H),8.11(1H),8.03(1H),7.8(1H),7.75(1H),7.68-7.69( 2H),7.63-7.64(4H),7.56-7.57(2H),7.49(1H),7.42(1H),7.37(2H),7.33(1H),7.21(1H),6.91(1H),6.56(1H).

[0404] Synthesis example E9:

[0405]

[0406] Add toluene solvent to the bottle, then add compound A8 1eq, intermediate 2 2.1eq in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add sodium tert-butoxide 1.5eq, Pd2(dba)3 0.01eq, S-Phos 0.02eq. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain a filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, dry in a vacuum oven for 3h to obtain a solid, and sublime the solid to obtain compound E9.

[0407] Mass spectrum m / z: 1001.16, element content (%): C71H44N4O3, C, 85.18; H, 4.43; O, 4.79; N, 5.60.

[0408] 1H NMR (300MHz, DMSO): 8.09(2H), 8.06(2H), 7.99(2H), 7.73-7.74(8H), 7.63-7.64(4H), 7.6(2H), 7.55-7.57(10H), 7.37-7.38(14H).

[0409] Synthesis example E10:

[0410]

[0411] Add toluene solvent to the bottle, then add 1.05eq of compound A1 and 1eq of compound A11 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of palladium acetate, and 0.02eq of X-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain a filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, and dry in a vacuum drying oven for 3h to obtain a solid intermediate 10.

[0412]

[0413] Add toluene solvent to the bottle, then add compound A8 1eq, intermediate 10 2.1eq in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add sodium tert-butoxide 1.5eq, Pd2(dba)3 0.01eq, and S-Phos 0.02eq. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain a filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, dry in a vacuum oven for 3h to obtain a solid, and sublime the solid to obtain compound E10.

[0414] Mass spectrum m / z: 1033.28, element content (%): C71H44N4OS2, C, 82.53; H, 4.29; O, 1.55; N, 5.42; S, 6.21.

[0415] 1H NMR (300MHz, DMSO): 8.18(2H),8.09(2H),8.06(2H),8.02(2H),7.99(2H),7.85(4 H),7.63-7.64(4H),7.6(2H),7.55-7.57(10H),7.51-7.53(4H),7.37-7.38(10H).

[0416] Synthesis example E11:

[0417]

[0418] Add toluene solvent to the bottle, then add 1.05eq of compound A6 and 1eq of compound A2 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of palladium acetate, and 0.02eq of X-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain a filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, and dry in a vacuum drying oven for 3h to obtain a solid intermediate 11.

[0419]

[0420] Add toluene solvent to the bottle, then add 1eq of compound A8 and 2.1eq of intermediate 11 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of Pd2(dba)3, and 0.02eq of S-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain a filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, dry in a vacuum drying oven for 3h to obtain a solid, and sublime the solid to obtain compound E11.

[0421] Mass spectrum m / z: 983.06, element content (%): C65H38N36O5, C, 79.42; H, 3.90; O, 8.14; N, 8.55.

[0422] 1H NMR (300MHz, DMSO): 8.43(2H), 7.73-7.74(8H), 7.63-7.64(6H), 7.56-7.57(4H), 7.37-7.38(12H), 7.33(2H), 7.21(2H), 6.56(2H).

[0423] Synthesis example E12:

[0424]

[0425] Add toluene solvent to the bottle, then add 1.05eq of compound A12 and 1eq of compound A2 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of palladium acetate, and 0.02eq of X-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain the filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, and dry in a vacuum oven for 3h to obtain a solid intermediate 12.

[0426]

[0427] Add toluene solvent to the bottle, then add 1eq of compound A8 and 1.1eq of intermediate 12 in sequence, fill with nitrogen, and heat to reflux for 0.5h. Add 1.5eq of sodium tert-butoxide, 0.01eq of Pd2(dba)3, and 0.02eq of S-Phos. Then fill with nitrogen and reflux for 10h. After the reaction is completed, cool to room temperature, extract, and filter through diatomaceous earth to obtain a filtrate. After concentration, heat, add a small amount of ethanol, stand to room temperature for recrystallization 4 times, filter to obtain a recrystallized solid, dry in a vacuum oven for 3h to obtain a solid, and sublime the solid to obtain compound E12.

[0428] Mass spectrum m / z: 1015.18, element content (%): C65H38N6O3S2, C, 76.90; H, 3.77; O, 4.73; N, 8.28, S, 6.32.

[0429] 1H NMR (300MHz, DMSO): 8.43(2H),8.18(2H),8.02(2H),7.85(4H),7.63-7.64(6H) ),7.56-7.57(4H),7.51-7.53(4H),7.37(8H),7.33(2H),7.21(2H),6.56(2H).

[0430] Comparative Example

[0431] The comparative example involves compounds Ref1 and Ref2, and the chemical structural formulas of the two compounds are shown below:

[0432]

[0433] Test Example 1

[0434] The refractive index and glass transition temperature of the compounds E1-E12 provided in the above synthesis examples and the compounds Ref1 and Ref2 provided in the comparative examples at different wavelengths were tested. The test results are shown in Table 1.

[0435] Table 1

[0436]

[0437] As can be seen from Table 1, the refractive index of the fluorenone derivative provided in the embodiment of the present application is significantly improved compared to the ref material, which is beneficial to improving the light extraction efficiency of the OLED device, obtaining a higher external quantum efficiency, reducing the loss of light inside the OLED device, and improving the device efficiency. At the same time, the glass transition temperature of the fluorenone derivative is relatively high, which is beneficial to improving the thermal stability of the OLED device.

[0438] Test Example 2

[0439] A plurality of OLED devices are provided. The OLED devices respectively use the compounds E1 to E12 provided in the above synthesis examples and the compounds Ref1 and Ref2 provided in the comparative examples as light extraction layers.

[0440] OLED devices are top-emitting devices prepared by vacuum evaporation, which include an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer (including host and guest doping), a hole blocking layer, an electron transport layer, an electron injection layer, a cathode, and a light extraction layer arranged in sequence.

[0441] Among them, the materials involved in each layer of the OLED device are as follows:

[0442]

[0443]

[0444] (1) The structure and layer thickness of the blue OLED device are as follows:

[0445] ITO / m-MTDATA:F4TCNQ 3%10nm / m-MTDATA 110nm / CBP 5nm / BH:BD 5%20nm / TPBI5nm / BCP:Liq 1:1 30nm / Yb 1nm / Mg:Ag 13nm / CPL 65nm.

[0446] The performance of the blue light OLED device was tested, and the test results are shown in Table 2.

[0447] Table 2

[0448] Light extraction layer Voltage efficiency Lifespan (LT95@1000nit) Comparative Example 1 CP1 100％ 100％ 100％ Comparative Example 2 CP2 100％ 102％ 101％ Example B-1 Compound E1 100％ 103％ 103％ Example B-2 Compound E2 100％ 103％ 104％ Example B-3 Compound E3 100％ 102％ 104％ Example B-4 Compound E4 100％ 104％ 103％ Example B-5 Compound E5 100％ 106％ 105％ Example B-6 Compound E6 100％ 107％ 104％ Example B-7 Compound E7 100％ 105％ 103％ Example B-8 Compound E8 100％ 106％ 102％ Example B-9 Compound E9 100％ 105％ 103％ Example B-10 Compound E10 100％ 107％ 102％ Example B-11 Compound E11 100％ 108％ 104％ Example B-12 Compound E12 100％ 109％ 103％

[0449] It can be seen from Table 2 that, compared with compounds Ref1 and Ref2, the blue light OLED device prepared by using the fluorenone compounds provided in the examples of the present application has improved device efficiency and lifespan.

[0450] (2) The structure and layer thickness of the green OLED device are as follows:

[0451] ITO / m-MTDATA:F4TCNQ 3%10nm / m-MTDATA 110nm / CBP 5nm / GH:GD 10%40nm / TPBI 5nm / BCP:Liq 1:1 30nm / Yb 1nm / Mg:Ag 13nm / CPL 65nm.

[0452] The green light OLED device was subjected to performance testing, and the test results are shown in Table 3.

[0453] Table 3

[0454] Light extraction layer Voltage efficiency Lifespan (LT95@1000nit) Comparative Example 1 CP1 100％ 100％ 100％ Comparative Example 2 CP2 100％ 102％ 101％ Example G-1 Compound E1 100％ 107％ 106％ Example G-2 Compound E2 100％ 105％ 103％ Example G-3 Compound E3 100％ 104％ 105％ Example G-4 Compound E4 100％ 106％ 102％ Example G-5 Compound E5 100％ 108％ 106％ Example G-6 Compound E6 100％ 112％ 105％ Example G-7 Compound E7 100％ 107％ 102％ Example G-8 Compound E8 100％ 108％ 104％ Example G-9 Compound E9 100％ 110％ 104％ Example G-10 Compound E10 100％ 112％ 103％ Example G-11 Compound E11 100％ 113％ 104％ Example G-12 Compound E12 100％ 115％ 102％

[0455] It can be seen from Table 3 that, compared with compounds Ref1 and Ref2, the green light OLED device prepared by using the fluorenone compounds provided in the examples of the present application has improved device efficiency and lifespan.

[0456] (3) The structure and layer thickness of the red OLED device are as follows:

[0457] ITO / m-MTDATA:F4TCNQ 3%10nm / m-MTDATA 110nm / CBP 5nm / RH:RD 3%45nm / TPBI5nm / BCP:Liq 1:1 30nm / Yb 1nm / Mg:Ag 13nm / CPL 65nm.

[0458] The performance of the red light OLED device was tested, and the test results are shown in Table 4.

[0459] Table 4

[0460]

[0461]

[0462] It can be seen from Table 4 that, compared with compounds Ref1 and Ref2, the red light OLED device prepared by using the fluorenone compounds provided in the examples of the present application has improved device efficiency and lifespan.

[0463] The above description is only for the purpose of facilitating those skilled in the art to understand the technical solution of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A fluorenone derivative, characterized in that: The fluorenone derivative comprises: fluorenone and a substituent group connected to at least one benzene ring in the fluorenone, and the chemical formula of the substituent group is as follows: Wherein, L1 and L2 are each independently selected from any one of a single bond, a substituted or unsubstituted C6-C36 arylene group, and a substituted or unsubstituted C2-C36 heteroarylene group; R1 and R2 are each independently selected from hydrogen, deuterium, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted C2-C12 heterocycloalkyl, substituted or unsubstituted C1-C12 alkoxy, substituted or unsubstituted C6-C36 aryl, substituted or unsubstituted C2-C36 heteroaryl, any one of Ar1, Ar2, Ar3, Ar4, Ar5 and Ar6; Among them, the chemical formulas of Ar1, Ar2, Ar3, Ar4, Ar5 and Ar6 are as follows: Multiple Zs are each independently C(r1) or N atom, and multiple r1s are each independently any one of hydrogen, deuterium, cyano, nitro, halogen atom, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted C2-C12 heterocycloalkyl, substituted or unsubstituted C1-C12 alkoxy, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C2-C30 heteroaryl; X1 and Y are selected from O atom, S atom, C(r2r3) or N(r4); r2 and r3 are each independently selected from any one of hydrogen, deuterium, cyano, nitro, a halogen atom, a substituted or unsubstituted C1-C12 alkyl group, a substituted or unsubstituted C2-C12 alkenyl group, a substituted or unsubstituted C3-C12 cycloalkyl group, a substituted or unsubstituted C2-C12 heterocycloalkyl group, a substituted or unsubstituted C1-C12 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, and a substituted or unsubstituted C2-C30 heteroaryl group; r4 is selected from any one of hydrogen, deuterium, cyano, nitro, a halogen atom, a substituted or unsubstituted C1-C12 alkyl group, a substituted or unsubstituted C2-C12 alkenyl group, a substituted or unsubstituted C3-C12 cycloalkyl group, a substituted or unsubstituted C2-C12 heterocycloalkyl group, a substituted or unsubstituted C1-C12 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, and a substituted or unsubstituted C2-C30 heteroaryl group; Ring A and Ring B are each independently selected from any one of a substituted or unsubstituted benzene ring, a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted anthracene ring, and a substituted or unsubstituted phenanthrene ring.

2. The fluorenone derivative according to claim 1, characterized in that The general chemical formula of the fluorenone derivative is as follows:

3. The fluorenone derivative according to claim 1, characterized in that The general chemical formula of the fluorenone derivative is as follows:

4. The fluorenone derivative according to any one of claims 1 to 3, characterized in that: The chemical formula of Ar1 is shown in any of the following:

5. The fluorenone derivative according to any one of claims 1 to 3, characterized in that: The chemical formula of Ar2 is shown in any of the following:

6. The fluorenone derivative according to any one of claims 1 to 3, characterized in that: The chemical formula of Ar3 is shown in any of the following:

7. The fluorenone derivative according to any one of claims 1 to 3, characterized in that: The chemical formula of Ar4 is shown in any of the following:

8. The fluorenone derivative according to any one of claims 1 to 3, characterized in that: The chemical formula of Ar5 is shown in any of the following:

9. The fluorenone derivative according to any one of claims 1 to 3, characterized in that: The chemical formula of Ar6 is shown in any of the following:

10. The fluorenone derivative according to any one of claims 1 to 9, characterized in that: L1 and L2 are each independently selected from a single bond or a phenylene group; R1 is selected from one of Ar1, Ar2, Ar3, Ar4, Ar5, and Ar6, and R2 is selected from another one of Ar1, Ar2, Ar3, Ar4, Ar5, and Ar6.

11. The method for preparing a fluorenone derivative according to any one of claims 1 to 10, characterized in that: The preparation method comprises: Providing a fluorenone halide and an amine compound corresponding to the substituent group; Under the conditions of protective atmosphere and the presence of a catalyst, the fluorenone halides and the amine compounds corresponding to the substituent groups undergo a nucleophilic substitution reaction to prepare the fluorenone derivatives.

12. The method for preparing a fluorenone derivative according to claim 11, characterized in that: The catalyst is a palladium catalyst.

13. A light extraction material, characterized in that: The light extraction material comprises the fluorenone derivative according to any one of claims 1 to 10.

14. The light extraction material according to claim 13, wherein The mass percentage of the fluorenone derivative is 100%.

15. The light extraction material according to claim 13, wherein The light extraction material further includes an auxiliary agent, and the auxiliary agent is selected from at least one of a material having a refractive index lower than that of a fluorenone derivative, a scattering agent, and a light stabilizer.

16. The light extraction material according to any one of claims 13 to 15, characterized in that: The refractive index of the light extraction material in the wavelength range of 460nm-620nm is greater than 2.

17. The light extraction material according to any one of claims 13 to 15, characterized in that: The glass transition temperature of the light extraction material is greater than or equal to 130°C.

18. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises an anode, a light-emitting functional layer, a cathode and a light extraction layer which are stacked in sequence, wherein the light extraction layer is made of the light extraction material according to any one of claims 13 to 17.

19. The organic electroluminescent device according to claim 18, characterized in that: The light-emitting functional layer comprises a hole transport unit, a light-emitting functional layer and an electron transport unit, and the hole transport unit, the light-emitting functional layer and the electron transport unit are sequentially stacked from the anode to the cathode; Wherein, the hole transport unit includes at least one of a hole injection layer, a hole transport layer, and an electron blocking layer; The electron transport unit includes at least one of a hole blocking layer, an electron transport layer, and an electron injection layer.

20. A display device, characterized in that: The display device comprises the organic electroluminescent device according to any one of claims 18 to 19.

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