A boron-containing organic compound and an organic electroluminescent device prepared therefrom

Abstract

The present invention discloses a boron-containing organic compound and an organic electroluminescent device prepared therefrom, belonging to the technical field of semiconductors. The structure of the organic compound of the present invention is shown in general formula (1). The compound of the present invention has a narrow full width at half maximum and a high fluorescence quantum yield, and can be used as a green light doping material for the light-emitting layer of an organic electroluminescent device, thereby improving the color purity and efficiency of the device.

Description

[0001] This divisional application of the present invention is based on the prior application with the application number: 2023101970803, the application date: March 2, 2023, and the invention title: A Boron-Containing Organic Compound and an Organic Electroluminescent Device Prepared Therefrom. Technical Field

[0002] The present invention relates to the field of semiconductor technology, and particularly to a boron-containing organic compound as an OLED doping material and an organic electroluminescent device comprising the same. Background Art

[0003] Limited by early technology, traditional fluorescent doping materials can only utilize 25% of the singlet excitons formed by electrical excitation for luminescence. The internal quantum efficiency of the device is relatively low (up to 25%), and the external quantum efficiency is generally lower than 5%, showing a large gap compared with the efficiency of phosphorescent devices. Due to the strong spin-orbit coupling of heavy atom centers, phosphorescent materials enhance intersystem crossing and can effectively utilize both singlet and triplet excitons formed by electrical excitation for luminescence, enabling the internal quantum efficiency of the device to reach 100%. However, most phosphorescent materials are expensive, have poor material stability, poor color purity, and serious efficiency roll-off problems of the device, which limit their application in OLEDs.

[0004] With the advent of the 5G era, higher requirements are put forward for the color rendering standard. In addition to being efficient and stable, luminescent materials also require a narrower full width at half maximum to improve the color purity of device luminescence. Fluorescent doping materials can achieve high fluorescence quantum and narrow full width at half maximum through molecular engineering. Breakthroughs have been achieved in blue fluorescent doping materials, and the full width at half maximum of boron-based materials can be reduced to less than 30 nm. In the green light region, to which the human eye is more sensitive, research mainly focuses on phosphorescent doping materials, but it is difficult to narrow their emission peak shape through simple methods. Therefore, to meet higher color rendering standards, it is of great significance to study efficient green fluorescent doping materials with narrow full width at half maximum.

[0005] In addition, the sensitization technology combines a triplet exciton sensitizing material with a fluorescent doping material. Using the triplet exciton sensitizing material as an exciton sensitizing medium, it fully utilizes triplet excitons and transfers energy to the fluorescent doping material through energy transfer, and can also achieve a 100% internal quantum efficiency of the device. This technology can make up for the deficiency of the exciton utilization rate of fluorescent doping materials and effectively play the characteristics of high fluorescence quantum yield, high device stability, high color purity, and low cost of fluorescent doping materials, showing broad prospects in the application of OLEDs.

[0006] Boron compounds with resonance structures are more likely to achieve narrow full-width at half-maximum (FWHM) luminescence. When such materials are applied in sensitization technologies, devices with high efficiency and narrow FWHM emission can be fabricated. For example, in CN 107507921 A and CN 110492006 A, a luminescent layer combination technology is disclosed, which uses a thermally activated delayed fluorescence (TADF) material with the lowest singlet and lowest triplet energy level difference less than or equal to 0.2 eV as the host and a boron-containing material as the dopant; in CN 110492005 A and CN 110492009 A, a luminescent layer combination scheme is disclosed, which uses an exciplex as the host and a boron-containing material as the dopant; both can achieve efficiency comparable to phosphorescence and a relatively narrow FWHM. Therefore, developing sensitization technologies based on narrow FWHM boron-based luminescent materials has unique advantages and strong potential in meeting the BT.2020 display specifications. Summary of the Invention

[0007] In view of the above problems existing in the prior art, the present invention provides a boron-containing organic compound and an organic electroluminescent device prepared therefrom. The compound of the present invention has a narrow FWHM and a high fluorescence quantum yield, and can be used as a green light doping material for the luminescent layer of an organic electroluminescent device, thereby improving the color purity and lifespan of the device.

[0008] The technical solution of the present invention is as follows: A boron-containing organic compound, the structure of the boron-containing organic compound is shown in the general formula (1):

[0009]

[0010] In the general formula (1), A1 and A2 each independently represent one of a substituted or unsubstituted C6-C 30 aryl, a substituted or unsubstituted C2-C 30 heteroaryl;

[0011] X represents O, S, N(R1), C(R2)(R3) or Si(R4)(R5); Z1 represents C-R6;

[0012] R1, R2, R3, R4, and R5 each independently represent one of a substituted or unsubstituted C1-C 10 alkyl, a substituted or unsubstituted C3-C 10 cycloalkyl, a substituted or unsubstituted C1-C 10 alkoxy, a substituted or unsubstituted C6-C 10 aryloxy, a substituted or unsubstituted C6-C 30 aryl, a substituted or unsubstituted C2-C 30 heteroaryl; R1 can also be connected to A1 to form a ring;

[0013] A3 represents the structure shown in the general formula (2):

[0014]

[0015] In general formula (2), Z2 is represented as C-R7;

[0016] Each occurrence of R6 and R7 is the same or different and is represented as a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a substituted or unsubstituted C1-C 10 alkoxy group, a substituted or unsubstituted C6-C 10 aryloxy group, a substituted or unsubstituted arylamino group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group;

[0017] The substituents for the substituting groups are each independently selected from a deuterium atom, a halogen atom, a cyano group, a C1-C 10 alkyl group, a C3-C 10 cycloalkyl group, a C6-C 30 aryl group, a C2-C 30 heteroaryl group, an amino group, or one or more of them;

[0018] The heteroatoms in the heteroaryl group are each independently selected from one or more of oxygen, sulfur, nitrogen, and silicon atoms.

[0019] Preferably, the structure of the organic compound is any one of general formula (3) and general formula (4):

[0020]

[0021] In general formula (3) and general formula (4), the meanings of A1, A2, X, Z1, and Z2 are as defined above.

[0022] Preferably, the structure of the organic compound is as shown in general formula (II-1) to general formula (II-10):

[0023]

[0024]

[0025] In general formula (II-1) to general formula (II-10), the meanings of A1, A2, Z1, Z2, R1, R2, R3, R4, and R5 are as defined above.

[0026] Preferably, the structure of the organic compound is any one of general formula (3-1) and general formula (4-1):

[0027]

[0028] In General Formulas (3-1) and (4-1), the meanings of X, Z1, and Z2 are the same as those defined above in the text.

[0029] Z3 is represented as C-R;

[0030] R is represented as a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a substituted or unsubstituted C1-C 10 alkoxy group, a substituted or unsubstituted C6-C 10 aryloxy group, a substituted or unsubstituted arylamino group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group;

[0031] The substituents for the substituted groups are each independently selected from a deuterium atom, a halogen atom, a cyano group, a C1-C 10 alkyl group, a C3-C 10 cycloalkyl group, a C6-C 30 aryl group, a C2-C 30 heteroaryl group, an amino group, or one or more of them;

[0032] The heteroatoms in the heteroaryl group are each independently selected from one or more of oxygen, sulfur, nitrogen, and silicon atoms.

[0033] In a preferred embodiment, the structure of the organic compound is any one of General Formulas (Ⅲ-1) to (Ⅲ-4):

[0034]

[0035] In General Formulas (Ⅲ-1) to (Ⅲ-4), Z1 is represented as C-R6;

[0036] Z2 is represented as C-R7; Z3 is represented as C-R;

[0037] Each occurrence of R6, R7, and R is the same as or different from each other and is represented as a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a substituted or unsubstituted C1-C 10 alkoxy group, a substituted or unsubstituted C6-C 10 aryloxy group, a substituted or unsubstituted arylamino group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group;

[0038] X is represented as O, S, N(R1), C(R2)(R3) or Si(R4)(R5);

[0039] R1, R2, R3, R4, and R5 are each independently represented as substituted or unsubstituted C1-C 10 alkyl, substituted or unsubstituted C3-C 10 cycloalkyl, substituted or unsubstituted C1-C 10 alkoxy, substituted or unsubstituted C6-C 10 aryloxy, substituted or unsubstituted C6-C 30 aryl, substituted or unsubstituted C2-C 30 heteroaryl;

[0040] R a 、R b 、R c 、R d 、R e 、R f are each independently represented as a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, substituted or unsubstituted C1-C 10 alkyl, substituted or unsubstituted C3-C 10 cycloalkyl, substituted or unsubstituted C1-C 10 alkoxy, substituted or unsubstituted C6-C 10 aryloxy, substituted or unsubstituted arylamino, substituted or unsubstituted C6-C 30 aryl, substituted or unsubstituted C2-C 30 heteroaryl;

[0041] The substituents for the substituted groups are each independently selected from a deuterium atom, a halogen atom, a cyano group, C1-C 10 alkyl, C3-C 10 cycloalkyl, C6-C 30 aryl, C2-C 30 heteroaryl, an amino group, or one or more thereof;

[0042] The heteroatoms in the heteroaryl are each independently selected from one or more of oxygen, sulfur, nitrogen, and silicon atoms.

[0043] In a preferred embodiment, R1, R2, R3, R4, and R5 are each independently selected from the group consisting of adamantyl, methyl, deuterated methyl, trifluoromethyl, ethyl, deuterated ethyl, isopropyl, deuterated isopropyl, tert-butyl, deuterated tert-butyl, cyclopentyl, deuterated cyclopentyl, methyl-substituted cyclopentyl, cyclohexyl, phenyl, deuterated phenyl, biphenyl, deuterated biphenyl, terphenyl, deuterated terphenyl, diphenyl ether group, methyl-substituted diphenyl ether group, naphthyl, anthracenyl, phenanthryl, pyridyl, phenyl-substituted pyridyl, quinolinyl, furyl, thienyl, benzofuranyl, dibenzofuranyl, dibenzothienyl, carbazolyl, N-phenylcarbazolyl, 9,9-dimethylfluorenyl, spirofluorene, methyl-substituted phenyl, ethyl-substituted phenyl, isopropyl-substituted phenyl, tert-butyl-substituted phenyl, methyl-substituted biphenyl, ethyl-substituted biphenyl, isopropyl-substituted biphenyl, tert-butyl-substituted biphenyl, deuterated methyl-substituted phenyl, deuterated ethyl-substituted phenyl, deuterated isopropyl-substituted phenyl, deuterated tert-butyl-substituted phenyl, deuterated methyl-substituted biphenyl, deuterated ethyl-substituted biphenyl, deuterated isopropyl-substituted biphenyl, deuterated tert-butyl-substituted biphenyl, tert-butyl-substituted dibenzofuranyl, phenyl-substituted tert-butyl, xanthenone group, phenyl-substituted triazinyl, phenyl-substituted boranyl, methoxy, and tert-butoxy;

[0044] R6, R7, R, R a , R b , R c , R d , R e , R fThey are respectively represented by one of a hydrogen atom, a deuterium atom, a halogen atom, an adamantyl group, a methyl group, a deuterated methyl group, a trifluoromethyl group, an ethyl group, a deuterated ethyl group, an isopropyl group, a deuterated isopropyl group, a tert-butyl group, a deuterated tert-butyl group, a cyclopentyl group, a deuterated cyclopentyl group, a methyl-substituted cyclopentyl group, a cyclohexyl group, a phenyl group, a deuterated phenyl group, a biphenyl group, a deuterated biphenyl group, a terphenyl group, a deuterated terphenyl group, a diphenyl ether group, a methyl-substituted diphenyl ether group, a naphthyl group, an anthracenyl group, a phenanthryl group, a pyrenyl group, a pyridyl group, a phenyl-substituted pyridyl group, a quinolinyl group, a furyl group, a thienyl group, a benzofuryl group, a dibenzofuryl group, a dibenzothienyl group, a carbazolyl group, an N-phenylcarbazolyl group, a 9,9-dimethylfluorenyl group, a spirofluorene group, a methyl-substituted phenyl group, an ethyl-substituted phenyl group, an isopropyl-substituted phenyl group, a tert-butyl-substituted phenyl group, a methyl-substituted biphenyl group, an ethyl-substituted biphenyl group, an isopropyl-substituted biphenyl group, a tert-butyl-substituted biphenyl group, a deuterated methyl-substituted phenyl group, a deuterated ethyl-substituted phenyl group, a deuterated isopropyl-substituted phenyl group, a deuterated tert-butyl-substituted phenyl group, a deuterated methyl-substituted biphenyl group, a deuterated ethyl-substituted biphenyl group, a deuterated isopropyl-substituted biphenyl group, a deuterated tert-butyl-substituted biphenyl group, a phenyl-substituted amino group, a tert-butylbenzene-substituted amino group, a tert-butyl-substituted dibenzofuryl group, a phenyl-substituted tert-butyl, an xanthone group, a phenyl-substituted triazine group, a phenyl-substituted boranyl group, a methoxy group, a tert-butoxy group, a diphenyl-substituted triazine group, a diphenylamino group.

[0045] In a preferred embodiment, the specific structural formula of the organic compound is any one of the following structures:

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057] An organic electroluminescent device includes a cathode and an anode, and an organic light-emitting functional layer therebetween. The organic light-emitting functional layer includes a light-emitting layer, and the light-emitting layer contains the boron-containing organic compound.

[0058] In a preferred embodiment, the light-emitting layer contains a host material and a doping material, and the doping material contains the boron-containing organic compound.

[0059] In a preferred embodiment, the light-emitting layer contains a first host material, a second host material and a doping material. At least one of the first host material and the second host material is a TADF material, and the doping material is the boron-containing organic compound.

[0060] In a preferred embodiment, the light-emitting layer contains a host material, an exciton sensitizing material and a doping material. The exciton sensitizing material is a metal element-containing complex, and the doping material is the boron-containing organic compound.

[0061] The beneficial technical effects of the present invention are as follows:

[0062] (1) The compound of the present invention can be used as a doping material for the light-emitting layer material in an OLED device, and can emit green fluorescence under the action of an electric field, and can be applied to the fields of OLED lighting or OLED display;

[0063] (2) The compound of the present invention as a doping material has a high fluorescence quantum efficiency, and the fluorescence quantum efficiency of the material is close to 100%;

[0064] (3) The compound of the present invention as a doping material, introducing a phosphorescent material as an exciton sensitizer, can effectively improve the device lifetime;

[0065] (4) The spectral FWHM of the compound of the present invention is narrow, which can effectively improve the device color gamut and the device luminous efficiency. Description of the Drawings

[0066] Figure 1 It is a schematic structural diagram of the materials listed in the present invention applied to an OLED device;

[0067] Among them, 1 is a transparent substrate layer, 2 is an anode layer, 3 is a hole injection layer, 4 is a hole transport layer, 5 is an electron blocking layer, 6 is a light-emitting layer, 7 is a hole blocking layer, 8 is an electron transport layer, 9 is an electron injection layer, and 10 is a cathode layer. Detailed Embodiments

[0068] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other. The present invention will be further described below in conjunction with the drawings and specific embodiments, but it is not limited to the present invention.

[0069] In the present invention, when describing electrodes, organic electroluminescent devices, and other structures, terms indicating directions such as "upper", "lower", "top", and "bottom" only represent the directions in a specific state and do not mean that the relevant structures can only exist in the described directions; on the contrary, if the structures can be transformed in position, for example, inverted, the directions of the structures will be changed accordingly. Specifically, in the present invention, the "bottom" and "lower" sides of the electrode refer to the side of the electrode close to the substrate during the preparation process, and the opposite side far from the substrate is the "top" and "upper" sides.

[0070] In the present invention, substituted or unsubstituted C6-C 30 aryl and / or substituted or unsubstituted C2-C 30 heteroaryl refers to substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted anthryl, substituted or unsubstituted phenanthryl, substituted or unsubstituted condensed tetraphenyl, substituted or unsubstituted pyrenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted p-terphenyl, substituted or unsubstituted m-terphenyl, substituted or unsubstituted group, substituted or unsubstituted terrylene, substituted or unsubstituted indenyl, substituted or unsubstituted furyl, substituted or unsubstituted thienyl, substituted or unsubstituted pyrrolyl, substituted or unsubstituted pyrazolyl, substituted or unsubstituted imidazolyl, substituted or unsubstituted triazolyl, substituted or unsubstituted oxazolyl, substituted or unsubstituted thiazolyl, substituted or unsubstituted oxadiazolyl, substituted or unsubstituted thiadiazolyl, substituted or unsubstituted pyridyl, substituted or unsubstituted pyrimidinyl, substituted or unsubstituted pyrazinyl, substituted or unsubstituted triazinyl, substituted or unsubstituted benzofuryl, substituted or unsubstituted benzothienyl, substituted or unsubstituted benzimidazolyl, substituted or unsubstituted indolyl, substituted or unsubstituted quinolinyl, substituted or unsubstituted isoquinolinyl, substituted or unsubstituted quinazolinyl, substituted or unsubstituted quinoxalinyl, substituted or unsubstituted naphthyridinyl, substituted or unsubstituted benzoxazinyl, substituted or unsubstituted benzothiazinyl, substituted or unsubstituted acridinyl, substituted or unsubstituted phenazinyl, substituted or unsubstituted phenothiazinyl, substituted or unsubstituted phenoxazinyl, substituted or unsubstituted fluorene, substituted or unsubstituted dibenzofuryl, substituted or unsubstituted dibenzothienyl, substituted or unsubstituted carbazolyl, their combinations or fused rings of the foregoing group combinations, but not limited thereto.

[0071] C1-C described in the present invention10 Alkyl groups (including straight-chain and branched-chain alkyl groups) refer to methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, isobutyl, sec-butyl, neopentyl, n-pentyl, isopentyl, octyl, heptyl, n-decyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 1-butylpentyl, etc., but are not limited thereto.

[0072] The halogen atoms in the present invention refer to chlorine atoms, fluorine atoms, bromine atoms, etc., but are not limited thereto.

[0073] C3-C in the present invention 10 Cycloalkyl groups refer to monovalent monocyclic saturated hydrocarbon groups containing 3 to 10 carbon atoms as ring-forming atoms. In this article, C4-C9 cycloalkyl groups are preferably used, C5-C8 cycloalkyl groups are more preferably used, and C5-C7 cycloalkyl groups are particularly preferably used. Non-limiting examples thereof may include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4,4-dimethylcyclohexyl, adamantyl, and cycloheptyl, etc., but are not limited thereto.

[0074] As the substrate of the organic electroluminescent device of the present invention, any substrate commonly used in organic electroluminescent devices can be used. Examples are transparent substrates such as glass or transparent plastic substrates; opaque substrates such as silicon substrates; flexible PI film substrates. Different substrates have different mechanical strengths, thermal stabilities, transparencies, surface smoothness, and water resistances. Depending on the nature of the substrate, its usage directions are different. In the present invention, a transparent substrate is preferably used. The thickness of the substrate is not particularly limited.

[0075] A first electrode is formed on the substrate, and the first electrode and the second electrode can be opposite to each other. The first electrode can be an anode. The first electrode can be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. When the first electrode is a transmissive electrode, it can be formed using a transparent metal oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium tin zinc oxide (ITZO), etc. When the first electrode is a semi-transmissive electrode or a reflective electrode, it can include Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a metal mixture. The thickness of the first electrode layer depends on the material used and is usually 50-500 nm, preferably 70-300 nm, and more preferably 100-200 nm.

[0076] The organic functional material layer disposed between the first electrode and the second electrode sequentially includes a hole transport region, a light-emitting layer, and an electron transport region from bottom to top.

[0077] In this article, the hole transport region constituting the organic electroluminescent device can include a hole injection layer, a hole transport layer, an electron blocking layer, etc.

[0078] As the material for the hole injection layer, hole transport layer, and electron blocking layer, any material can be selected from known related materials for OLED devices for use.

[0079] Examples of the above materials may be phthalocyanine derivatives, triazole derivatives, triarylmethane derivatives, triarylamine derivatives, oxazole derivatives, oxadiazole derivatives, hydrazone derivatives, stilbene derivatives, pyridinoline derivatives, polysilane derivatives, imidazole derivatives, phenylenediamine derivatives, amino-substituted quinone derivatives, styryl anthracene derivatives, styrylamine derivatives and other styrene compounds, fluorene derivatives, spirofluorene derivatives, silazane derivatives, aniline copolymers, porphyrin compounds, carbazole derivatives, polyarylalkane derivatives, polyphenylene vinyl and its derivatives, polythiophene and its derivatives, poly-N-vinylcarbazole derivatives, thiophene oligomers and other conductive polymer oligomers, aromatic tertiary amine compounds, styrylamine compounds, triamines, tetraamines, benzidine compounds, propynediamine derivatives, p-phenylenediamine derivatives, m-phenylenediamine derivatives, 1,1'-bis(4-diarylaminophenyl)cyclohexane, 4,4'-bis(diarylamino)biphenyls, bis[4-(diarylamino)phenyl]methanes, 4,4'-bis(diarylamino)terphenyls, 4,4'-bis(diarylamino)quaterphenyls, 4,4'-bis(diarylamino)diphenyl ethers, 4,4'-bis(diarylamino)diphenyl sulfides, bis[4-(diarylamino)phenyl]dimethylmethanes, bis[4-(diarylamino)phenyl]-bis(trifluoromethyl)methanes or 2,2-diphenylethylene compounds, etc.

[0080] Furthermore, according to the device matching requirements, the hole transport film layer between the hole transport auxiliary layer and the hole injection layer that constitutes the organic electroluminescent device can be a single film layer or a stacked structure of multiple hole transport materials. In this article, for the above various hole carrier conduction film layers with different functions, their film thicknesses are not particularly limited.

[0081] The hole injection layer contains a host organic material that can conduct holes, and also contains a P-type doping material with a deep HOMO energy level (the corresponding LUMO energy level will also be deep). Based on empirical summaries, in order to achieve smooth injection of holes from the anode to the organic film layer, the HOMO energy level of the host organic material that conducts holes used in the anode interface buffer layer must have certain characteristics with the P-doping material, so as to be expected to achieve the occurrence of the charge transfer state between the host material and the doping material, achieve Ohmic contact between the buffer layer and the anode, and achieve efficient injection from the electrode to hole injection conduction.

[0082] In view of the above empirical summary, for hole-type host materials with different HOMO energy levels, different P-doped materials need to be selected to match them in order to achieve ohmic contact at the interface and improve the hole injection effect.

[0083] Therefore, in one embodiment of the present invention, in order to better inject holes, the hole injection layer further comprises a charge-conductive P-type doped material selected from the following: quinone derivatives such as tetracyanoquinodimethane (TCNQ) and 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinodimethane (F4-TCNQ); or hexaazatriphenylene derivatives such as 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (HAT-CN); or cyclopropane derivatives such as 4,4',4”-((1E,1'E,1”E)-cyclopropane-1,2,3-trimethylenetri(cyanomethanylidene))tris(2,3,5,6-tetrafluorobenzyl); or metal oxides such as tungsten oxide and molybdenum oxide, but not limited thereto.

[0084] In the hole injection layer of the present invention, the ratio of the hole transport material to the P-type doped material used is 99:1 - 95:5, preferably 99:1 - 97:3, based on mass.

[0085] The thickness of the hole injection layer of the present invention can be 5 - 100 nm, preferably 5 - 50 nm and more preferably 5 - 20 nm, but the thickness is not limited to this range.

[0086] The thickness of the hole transport layer of the present invention can be 5 - 200 nm, preferably 10 - 150 nm and more preferably 20 - 100 nm, but the thickness is not limited to this range.

[0087] The thickness of the electron blocking layer of the present invention can be 1 - 50 nm, preferably 5 - 30 nm, but the thickness is not limited to this range.

[0088] After forming the hole injection layer, the hole transport layer and the electron blocking layer, a corresponding light-emitting layer is formed on the electron blocking layer.

[0089] The light-emitting layer may comprise a host material and a doping material. The host material may use common green light host materials in the art, and the doping material uses the boron-containing organic compound represented by the general formula (1) of the present invention.

[0090] In the light-emitting layer of the present invention, the ratio of the host material to the doping material used is 99:1 - 70:30, preferably 99:1 - 85:15 and more preferably 97:3 - 87:13, based on mass.

[0091] The thickness of the light-emitting layer can be adjusted to optimize the light-emitting efficiency and driving voltage. The preferred thickness range is 5 nm to 50 nm, more preferably 10 - 50 nm, and even more preferably 15 - 30 nm, but the thickness is not limited to this range.

[0092] In the present invention, the electron transport region may sequentially include, from bottom to top, a hole blocking layer, an electron transport layer, and an electron injection layer disposed above the light-emitting layer, but is not limited thereto.

[0093] The hole blocking layer is a layer that blocks holes injected from the anode from passing through the light-emitting layer and entering the cathode, thereby extending the lifespan of the device and improving the efficiency of the device. The hole blocking layer of the present invention can be disposed above the light-emitting layer. As the hole blocking layer material of the organic electroluminescent device of the present invention, compounds known in the prior art with hole blocking effects can be used, for example, phenanthroline derivatives such as bathocuproine (referred to as BCP), metal complexes of hydroxyquinoline derivatives such as aluminum(III) bis(2-methyl-8-quinolinolato)-4-phenylphenolate (BAlq), various rare earth complexes, oxazole derivatives, triazole derivatives, triazine derivatives, 9,9'-(5-(6-([1,1'-biphenyl]-4-yl)-2-phenylpyrimidin-4-yl)-1,3-phenylene)bis(9H-carbazole) (CAS No.: 1345338-69-3) and other pyrimidine derivatives, etc. The thickness of the hole blocking layer of the present invention can be 2 - 200 nm, preferably 5 - 150 nm, and more preferably 10 - 100 nm, but the thickness is not limited to this range.

[0094] The electron transport layer can be disposed above the light-emitting layer or (if present) the hole blocking layer. The electron transport layer material is a material that easily receives electrons from the cathode and transfers the received electrons to the light-emitting layer. Materials with high electron mobility are preferred. As the electron transport layer material of the organic electroluminescent device of the present invention, electron transport layer materials known in the prior art for organic electroluminescent devices can be used, for example, metal complexes of hydroxyquinoline derivatives represented by Alq3, BAlq, and Liq, various rare earth metal complexes, triazole derivatives, 2,4-bis(9,9-dimethyl-9H-fluoren-2-yl)-6-(naphthalen-2-yl)-1,3,5-triazine (CAS No.: 1459162-51-6) and other triazine derivatives, 2-(4-(9,10-di(naphthalen-2-yl)anthracen-2-yl)phenyl)-1-phenyl-1H-benzo[d]imidazole (CAS No.: 561064-11-7, commonly known as LG201) and other imidazole derivatives, oxadiazole derivatives, thiadiazole derivatives, carbodiimide derivatives, quinoxaline derivatives, phenanthroline derivatives, silicon-based compound derivatives, etc. The thickness of the electron transport layer of the present invention can be 10 - 80 nm, preferably 20 - 60 nm, and more preferably 25 - 45 nm, but the thickness is not limited to this range.

[0095] The electron injection layer may be disposed above the electron transport layer. The material of the electron injection layer is generally preferably a material with a low work function, such that electrons can be easily injected into the organic functional material layer. As the material of the electron injection layer of the organic electroluminescent device of the present invention, the materials known in the prior art for the electron injection layer of organic electroluminescent devices can be used, for example, lithium; lithium salts such as lithium 8-hydroxyquinoline, lithium fluoride, lithium carbonate or lithium azide; or cesium salts, cesium fluoride, cesium carbonate or cesium azide. The thickness of the electron injection layer of the present invention may be 0.1 - 5 nm, preferably 0.5 - 3 nm and more preferably 0.8 - 1.5 nm, but the thickness is not limited to this range.

[0096] The second electrode may be disposed above the electron transport region. The second electrode may be a cathode. The second electrode may be a transmissive electrode, a semi-transmissive electrode or a reflective electrode. When the second electrode is a transmissive electrode, the second electrode may include, for example, Li, Yb, Ca, LiF / Ca, LiF / Al, Al, Mg, BaF, Ba, Ag or a compound or mixture thereof; when the second electrode is a semi-transmissive electrode or a reflective electrode, the second electrode may include Ag, Mg, Yb, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti or a compound or mixture thereof, but is not limited thereto. The thickness of the cathode depends on the material used and is generally 10 - 50 nm, preferably 15 - 20 nm.

[0097] The organic electroluminescent device of the present invention may further include a packaging structure. The packaging structure may be a protective structure for preventing external substances such as moisture and oxygen from entering the organic layer of the organic electroluminescent device. The packaging structure may be, for example, a can, such as a glass can or a metal can; or a thin film covering the entire surface of the organic layer.

[0098] A method for preparing the organic electroluminescent device of the present invention includes successively laminating an anode, a hole injection layer, a hole transport layer, an electron blocking layer, an organic film layer, an electron transport layer, an electron injection layer and a cathode, and optionally a covering layer on a substrate. In this regard, methods such as vacuum deposition, vacuum evaporation, spin coating, casting, LB method, inkjet printing, laser printing or LITI may be used, but are not limited thereto. In the present invention, vacuum evaporation is preferably used to form each layer. Those skilled in the art can conventionally select each process condition in the vacuum evaporation method according to actual needs.

[0099] The raw materials involved in the synthesis examples of the present invention can all be purchased from the market or prepared by conventional preparation methods in the art;

[0100] Synthesis of Compound 8 in Example 1:

[0101]

[0102] Under nitrogen protection, 10 mmol of raw material A-1, 10 mmol of N-chlorosuccinimide (NCS), 20 mL of acetonitrile, and 1 mmol of thiourea were added to a three-necked flask and stirred at room temperature for 2 hours. After the reaction was completed, the reaction solution was concentrated, and the intermediate a-1 was obtained by column chromatography. LC-MS: Measured value: 208.13 ([M+H] + ), Theoretical value: 207.08.

[0103] 10 mmol of intermediate a-1, 10 mmol of raw material B-1, 1.0 mmol of Cu powder, 20 mmol of K2CO3, 20 mmol of Na2SO4, and 50 mL of 1,2-dichlorobenzene were added to a three-necked flask, heated to 190 °C, and stirred for 12 hours. After the reaction was completed, 1,2-dichlorobenzene was removed, the organic layer was separated with dichloromethane, and then the organic phase was dried with anhydrous magnesium sulfate. The solvent was removed under reduced pressure, and the intermediate b-1 was purified by silica gel column chromatography (eluent: hexane:CH2Cl2 = 2:1). LC-MS: Measured value: 418.21 ([M+H] + ), Theoretical value: 417.09.

[0104] 10 mmol of intermediate b-1, 1.5 mmol of Pd(OAc)2, 50 mmol of K2CO3, 10 mmol of BnEt3NCl, 3.5 mmol of PPh3, and 50 mL of DMA were added to a three-necked flask and stirred at 100 °C for 6 hours. After the reaction was completed, DMA was removed, the organic layer was separated with dichloromethane, and then the organic phase was dried with anhydrous magnesium sulfate. The solvent was removed under reduced pressure, and the intermediate c-1 was purified by silica gel column chromatography (eluent: hexane:CH2Cl2 = 2:1). LC-MS: Measured value: 338.10 ([M+H] + ), Theoretical value: 337.16.

[0105] Under nitrogen protection, 10 mmol of intermediate c-1, 11 mmol of raw material C-1, 1 mmol of X-phos, 20 mmol of Cs2CO3, and a mixed solution of toluene / EtOH / H2O (80 mL / 40 mL / 40 mL) were added to a three-necked flask, and then 0.5 mmol of Pd(OAc)2 was added. The mixture was stirred at 110 °C for 12 hours. After the reaction was completed, it was extracted with dichloromethane, and then the organic phase was dried with anhydrous magnesium sulfate. The solvent was removed, and the intermediate d-1 was purified by silica gel column chromatography (eluent: hexane:CH2Cl2 = 2:1). LC-MS: Measured value: 481.22 ([M+H] + ), Theoretical value: 480.28.

[0106] 10 mmol of intermediate d-1, 30 mmol of triphenylphosphine, and 50 ml of 1,2-dichlorobenzene were added to a three-necked flask, and the mixture was stirred and reacted for 12 hours. After the reaction was completed, the mixture was extracted with dichloromethane, and then the organic phase was dried over anhydrous magnesium sulfate. The solvent was removed, and the residue was purified by silica gel column chromatography (eluent: hexane:CH2Cl2 = 2:1) to obtain intermediate e-1. LC-MS: measured value: 449.31 ([M+H] + ), theoretical value: 448.29.

[0107] Under nitrogen protection, 0.90 mmol of raw material D-1, 1.35 mmol of intermediate e-1, 5.20 mmol of K2CO3, and 20 mL of DMF were added to a three-necked flask, and then the mixture was heated to 110 °C. After stirring for 3 hours, the reaction mixture was cooled to room temperature. The reaction mixture was poured into a large amount of MeOH to form a precipitate. After filtration, the obtained solid was washed with MeOH, and the obtained filtrate was evaporated under vacuum. The obtained residue was purified by silica gel column chromatography (eluent: PE:DCM = 5:1) to obtain intermediate f-1. LC-MS: measured value: 659.12 ([M+H] + ), theoretical value: 658.29.

[0108] Under nitrogen protection, 0.90 mmol of raw material E-1, 1.35 mmol of intermediate f-1, 5.20 mmol of K2CO3, and 20 mL of DMF were added to a three-necked flask, and then the mixture was heated to 110 °C. After stirring for 3 hours, the reaction mixture was cooled to room temperature. The reaction mixture was poured into a large amount of MeOH to form a precipitate. After filtration, the obtained solid was washed with MeOH, and the obtained filtrate was evaporated under vacuum. The obtained residue was purified by silica gel column chromatography (eluent: PE:DCM = 5:1) to obtain intermediate g-1. LC-MS: measured value: 729.52 ([M+H] + ), theoretical value: 728.47.

[0109] In a three-necked flask, under nitrogen protection, 2.20 mmol of boron tribromide and 1.10 mmol of intermediate g-1 were dissolved in 30 mL of 1,2,4-trichlorobenzene. After stirring at 180 °C for 20 hours, the reaction mixture was diluted with dichloromethane (50 mL), and 100 mL of sodium phosphate buffer solution with pH = 6 was added at 0 °C. The aqueous layer was separated and extracted with dichloromethane (100 mL, three times). The crude product was purified by silica gel column chromatography (eluent: hexane / CH2Cl2 = 5 / 1) to obtain the target compound 8.

[0110] Synthesis of Compound 34 in Example 2:

[0111]

[0112] 10.0 mmol of starting material A-1 and 20 mL of THF were added to a three-necked flask, and then at -70 °C, butyllithium (4.2 mL, 2.5 M hexane solution) was added dropwise. The resulting suspension was maintained at -70 °C for 30 minutes, bubbled with CO2 for 10 min, and the clear solution was allowed to stand for 10 minutes. Then the solvent was evaporated (0 °C, 1 mmHg), the crystalline residue was dissolved in 20 mL of dry THF, and cooled to -70 °C, and then tert-butyllithium (6.2 mL, 1.7 M pentane solution) was added dropwise. After the resulting yellow solution was maintained at -70 °C for 1 h, 10.0 mmol of C2Cl6 was added, and then the reaction mixture was maintained at -70 °C for 1 hour, 1 mL of water was added, and the solution was brought to room temperature. Then it was poured into NH4Cl (saturated aqueous solution, 50 mL) with stirring, 50 mL of ether was added, the organic phase was separated, washed with brine, and then the organic phase was dried over anhydrous magnesium sulfate. The solvent was removed, and the solid residue was purified by flash chromatography (hexane / ether = 4:1) to obtain intermediate a-2. LC-MS: found: 208.02 ([M+H] + ) and theoretical value: 207.08.

[0113] Intermediate b-2 was prepared in the same manner as intermediate b-1, except that intermediate a-2 was used in place of intermediate a-1 to obtain intermediate b-2. LC-MS: found: 418.20 ([M+H] + ) and theoretical value: 417.09.

[0114] Intermediate c-2 was prepared in the same manner as intermediate c-1, except that intermediate b-2 was used in place of intermediate b-1 to obtain intermediate c-2. LC-MS: found: 338.08 ([M+H] + ) and theoretical value: 337.16.

[0115] Intermediate d-2 was prepared in the same manner as intermediate d-1, except that intermediate c-2 was used in place of intermediate c-1 to obtain intermediate d-2. LC-MS: found: 481.32 ([M+H] + ) and theoretical value: 480.28.

[0116] Intermediate e-2 was prepared in the same manner as intermediate e-1, except that intermediate d-2 was used in place of intermediate d-1 to obtain intermediate e-2. LC-MS: found: 449.18 ([M+H] + ) and theoretical value: 448.29.

[0117] The preparation method of intermediate f-2 is the same as that of intermediate f-1, except that intermediate e-2 is used to replace intermediate e-1, and raw material D-2 is used to replace raw material D-1 to obtain intermediate f-2. LC-MS: Measured value: 603.20 ([M+H] + ), theoretical value: 602.23.

[0118] The preparation method of intermediate g-2 is the same as that of intermediate g-1, except that intermediate f-2 is used to replace intermediate f-1 to obtain intermediate g-2. LC-MS: Measured value: 673.26 ([M+H] + ), theoretical value: 672.41.

[0119] The preparation method of compound 34 is the same as that of compound 8, except that intermediate g-2 is used to replace intermediate g-1 to obtain compound 34.

[0120] Synthesis of compound 43 in Example 3:

[0121]

[0122] The preparation method of intermediate f-3 is the same as that of intermediate f-2, except that raw material D-3 is used to replace raw material D-2 to obtain intermediate f-3. LC-MS: Measured value: 834.19 ([M+H] + ), theoretical value: 833.31.

[0123] The preparation method of intermediate g-3 is the same as that of intermediate g-1, except that intermediate f-3 is used to replace intermediate f-1 to obtain intermediate g-3. LC-MS: Measured value: 904.41 ([M+H] + ), theoretical value: 903.49.

[0124] The preparation method of compound 43 is the same as that of compound 8, except that intermediate g-3 is used to replace intermediate g-1 to obtain compound 43.

[0125] Synthesis of compound 60 in Example 4:

[0126]

[0127] The preparation method of intermediate g-4 is the same as that of intermediate g-1, except that raw material E-4 is used to replace raw material E-1 to obtain intermediate g-4. LC-MS: Measured value: 745.60 ([M+H] + ), theoretical value: 744.45.

[0128] The preparation method of compound 60 is the same as that of compound 8, except that intermediate g-4 is used to replace intermediate g-1 to obtain compound 60.

[0129] Synthesis of Compound 86 in Example 5:

[0130]

[0131] The preparation method of intermediate f-5 is the same as that of intermediate f-2, except that raw material D-1 is used to replace raw material D-2 to obtain intermediate f-5. LC-MS: Measured value: 659.41 ([M+H] + ), Theoretical value: 658.29.

[0132] The preparation method of intermediate g-5 is the same as that of intermediate g-2, except that intermediate f-5 is used to replace intermediate f-2 and raw material E-4 is used to replace raw material E-1 to obtain intermediate g-5. LC-MS: Measured value: 745.48 ([M+H] + ), Theoretical value: 744.45.

[0133] The preparation method of compound 86 is the same as that of compound 8, except that intermediate g-5 is used to replace intermediate g-1 to obtain compound 86.

[0134] Synthesis of Compound 112 in Example 6:

[0135]

[0136] The preparation method of intermediate g-6 is the same as that of intermediate g-1, except that raw material E-6 is used to replace raw material E-1 to obtain intermediate g-6. LC-MS: Measured value: 860.62 ([M+H] + ), Theoretical value: 859.58.

[0137] The preparation method of compound 112 is the same as that of compound 8, except that intermediate g-6 is used to replace intermediate g-1 to obtain compound 112.

[0138] Synthesis of Compound 121 in Example 7:

[0139]

[0140] The preparation method of intermediate f-7 is the same as that of intermediate f-1, except that raw material D-3 is used to replace raw material D-1 to obtain intermediate f-7. LC-MS: Measured value: 834.28 ([M+H] + ), Theoretical value: 833.31.

[0141] The preparation method of intermediate g-7 is the same as that of intermediate g-1, except that intermediate f-7 is used to replace intermediate f-1 and raw material E-6 is used to replace raw material E-1 to obtain intermediate g-7. LC-MS: Measured value: 1035.44 ([M+H] + ), Theoretical value: 1034.60.

[0142] The preparation method of Compound 121 is the same as that of Compound 8, except that Intermediate g-7 is used to replace Intermediate g-1 to obtain Compound 121.

[0143] Synthesis of Compound 141 in Example 8:

[0144]

[0145] The preparation method of Intermediate g-8 is the same as that of Intermediate g-5, except that Raw Material E-6 is used to replace Raw Material E-4 to obtain Intermediate g-8. LC-MS: Measured value: 860.64 ([M+H] + ) and theoretical value: 859.58.

[0146] The preparation method of Compound 141 is the same as that of Compound 8, except that Intermediate g-8 is used to replace Intermediate g-1 to obtain Compound 141.

[0147] Synthesis of Compound 169 in Example 9:

[0148]

[0149] The preparation method of Intermediate g-9 is the same as that of Intermediate g-1, except that Raw Material E-9 is used to replace Raw Material E-1 to obtain Intermediate g-9. LC-MS: Measured value: 858.42 ([M+H] + ) and theoretical value: 857.56.

[0150] The preparation method of Compound 169 is the same as that of Compound 8, except that Intermediate g-9 is used to replace Intermediate g-1 to obtain Compound 169.

[0151] Synthesis of Compound 196 in Example 10:

[0152]

[0153] The preparation method of Intermediate g-10 is the same as that of Intermediate g-5, except that Raw Material E-9 is used to replace Raw Material E-4 to obtain Intermediate g-10. LC-MS: Measured value: 858.59 ([M+H] + ) and theoretical value: 857.56.

[0154] The preparation method of Compound 196 is the same as that of Compound 8, except that Intermediate g-10 is used to replace Intermediate g-1 to obtain Compound 196.

[0155] Synthesis of Compound 206 in Example 11:

[0156]

[0157] The preparation method of intermediate g-11 is the same as that of intermediate g-3, except that raw material E-9 is used to replace raw material E-1 to obtain intermediate g-11. LC-MS: measured value: 1033.46 ([M+H] + ), theoretical value: 1032.58.

[0158] The preparation method of compound 206 is the same as that of compound 8, except that intermediate g-11 is used to replace intermediate g-1 to obtain compound 206.

[0159] Synthesis of compound 233 in Example 12:

[0160]

[0161] The preparation method of intermediate b-3 is the same as that of intermediate b-2, except that raw material A-2 is used to replace intermediate a-2 to obtain intermediate b-3. LC-MS: measured value: 362.05, theoretical value: 361.02.

[0162] The preparation method of intermediate c-3 is the same as that of intermediate c-2, except that intermediate b-3 is used to replace intermediate b-2 to obtain intermediate c-3. LC-MS: measured value: 282.13, theoretical value: 281.10.

[0163] The preparation method of intermediate d-3 is the same as that of intermediate d-2, except that intermediate c-3 is used to replace intermediate c-2 to obtain intermediate d-3. LC-MS: measured value: 369.17, theoretical value: 368.15.

[0164] The preparation method of intermediate e-3 is the same as that of intermediate e-2, except that intermediate d-3 is used to replace intermediate d-2 to obtain intermediate e-3. LC-MS: measured value: 337.22, theoretical value: 336.16.

[0165] The preparation method of intermediate f-8 is the same as that of intermediate f-2, except that intermediate e-3 is used to replace intermediate e-2 and raw material D-3 is used to replace raw material D-2 to obtain intermediate f-8. LC-MS: measured value: 565.20, theoretical value: 564.16.

[0166] Under nitrogen protection, 0.90 mmol of raw material E-9, 1.0 mmol of intermediate f-8, 5.20 mmol of K2CO3 and 20 mL of DMF were added to a three-necked flask, and then heated to 110 °C. After stirring for 3 hours, the reaction mixture was cooled to room temperature. The reaction mixture was poured into a large amount of MeOH to form a precipitate. After filtration, the obtained solid was washed with MeOH, and the obtained filtrate was evaporated under vacuum. The obtained residue was purified by silica gel column chromatography (eluent: PE:DCM = 5:1) to obtain intermediate g-12, LC-MS: measured value: 824.41, theoretical value: 823.35.

[0167] In a sealed pressure-resistant tube, under nitrogen protection, 10 mmol of intermediate g-12 and 85 mL of o-dichlorobenzene were added. A 10 mmol solution of 2.5 M tert-butyllithium in n-hexane was added at 0 °C, and the system was heated to 60 °C and reacted for 4 hours. Then, 15 mmol of boron tribromide was added at 0 °C, and the reaction was continued at room temperature for 3 hours. Then, 20 mmol of N,N-diisopropylethylamine was added to the system at 0 °C, and the system was heated to 200 °C and reacted for 12 hours. After the reaction, the organic layer was concentrated under reduced pressure and then purified by silica gel column chromatography to obtain compound 233.

[0168] The structural characterizations of the compounds obtained in each example are shown in Table 1

[0169] Table 1

[0170]

[0171] The compounds of the present invention can be used in light-emitting devices and can be used as doping materials for the light-emitting layer. The physical and chemical properties of the compounds prepared in the above examples of the present invention were tested, and the test results are shown in Table 2:

[0172] Table 2

[0173]

[0174]

[0175] Note: PLQY (fluorescence quantum yield) and FWHM (full width at half maximum) were measured by a Horiba Fluorolog-3 series fluorescence spectrometer in the thin film state.

[0176] As can be seen from the data in Table 2 above, the compounds of the present invention have a high fluorescence quantum efficiency as doping materials, and the fluorescence quantum efficiency of the materials is close to 100%; at the same time, the spectral FWHM of the materials is narrow, which can effectively improve the color gamut of the device and the light-emitting efficiency of the device.

[0177] The application effects of the synthesized OLED materials of the present invention in devices are described in detail below through Device Examples 1-12 and Device Comparative Examples 1-3. The manufacturing processes of the devices in Device Examples 2-12 and Device Comparative Examples 1-3 of the present invention are exactly the same as those of Device Example 1, and the same substrate materials and electrode materials are used, and the film thicknesses of the electrode materials are also kept consistent. The difference is that the light-emitting layer materials in the devices are replaced. The layer structures and test results of each device example are shown in Table 3 and Table 4 respectively.

[0178] Device Example 1

[0179] As Figure 1 shown, the transparent substrate layer 1 is a transparent PI film. The ITO anode layer 2 (with a film thickness of 150 nm) is washed, that is, washed successively with a cleaning agent (Semiclean M-L20), pure water, and dried, and then washed with ultraviolet-ozone to remove organic residues on the surface of the transparent ITO. On the ITO anode layer 2 after the above washing, using a vacuum evaporation device, HT-1 and HI-1 with a film thickness of 10 nm are evaporated as the hole injection layer 3, and the mass ratio of HT-1 and HI-1 is 97:3. Then, HT-1 with a thickness of 60 nm is evaporated as the hole transport layer 4. Subsequently, EB-1 with a thickness of 30 nm is evaporated as the electron blocking layer 5. After the evaporation of the above electron blocking material is completed, the light-emitting layer 6 of the OLED light-emitting device is fabricated. GH-1 and GH-2 are used as the host materials, and Compound 8 is used as the doping material. The mass ratio of GH-1, GH-2, and Compound 8 is 69:30:1, and the film thickness of the light-emitting layer is 30 nm. After the above light-emitting layer 6, HB-1 is continuously evaporated by vacuum evaporation, with a film thickness of 5 nm. This layer is the hole blocking layer 7. After the above hole blocking layer 7, ET-1 and Liq are continuously evaporated by vacuum evaporation, and the mass ratio of ET-1 and Liq is 1:1, with a film thickness of 30 nm. This layer is the electron transport layer 8. On the electron transport layer 8, a LiF layer with a film thickness of 1 nm is fabricated through a vacuum evaporation device. This layer is the electron injection layer 9. On the electron injection layer 9, a Mg:Ag electrode layer with a film thickness of 80 nm is fabricated through a vacuum evaporation device. The mass ratio of Mg and Ag is 1:9. This layer is used as the cathode layer 10.

[0180] The application effects of the synthesized OLED materials of the present invention in devices are described in detail below through Device Examples 13-24 and Device Comparative Examples 4-6. The manufacturing processes of the devices in Device Examples 14-24 and Device Comparative Examples 4-6 of the present invention are exactly the same as those of Device Example 13, and the same substrate materials and electrode materials are used, and the film thicknesses of the electrode materials are also kept consistent. The difference is that the light-emitting layer materials in the devices are replaced. The layer structures and test results of each device example are shown in Table 3 and Table 4 respectively.

[0181] Device Example 13

[0182] The transparent substrate layer 1 is a transparent PI film. The ITO anode layer 2 (with a film thickness of 150 nm) is washed, that is, washed successively with a cleaning agent (Semiclean M-L20), pure water, and then dried, and then washed with ultraviolet-ozone to remove organic residues on the surface of the transparent ITO. On the ITO anode layer 2 after the above washing, using a vacuum evaporation device, HT-1 and HI-1 with a film thickness of 10 nm are evaporated as the hole injection layer 3, and the mass ratio of HT-1 and HI-1 is 97:3. Then, HT-1 with a thickness of 60 nm is evaporated as the hole transport layer 4. Subsequently, EB-1 with a thickness of 30 nm is evaporated as the electron blocking layer 5. After the evaporation of the above electron blocking material is completed, the light-emitting layer 6 of the OLED light-emitting device is fabricated. GH-1 and GH-2 are used as the host materials, GD-1 is used as the first doping material, and compound 8 is used as the second doping material. The mass ratio of GH-1, GH-2, GD-1, and compound 8 is 66:30:3:1, and the film thickness of the light-emitting layer is 30 nm. After the above light-emitting layer 6, HB-1 is continuously vacuum-evaporated with a film thickness of 5 nm, and this layer is the hole blocking layer 7. After the above hole blocking layer 7, ET-1 and Liq are continuously vacuum-evaporated, and the mass ratio of ET-1 and Liq is 1:1, with a film thickness of 30 nm, and this layer is the electron transport layer 8. On the electron transport layer 8, a LiF layer with a film thickness of 1 nm is fabricated through a vacuum evaporation device, and this layer is the electron injection layer 9. On the electron injection layer 9, a Mg:Ag electrode layer with a film thickness of 80 nm is fabricated through a vacuum evaporation device, and the mass ratio of Mg and Ag is 1:9, and this layer is used as the cathode layer 10.

[0183] The molecular structural formulas of the related materials are as follows:

[0184]

[0185] After the OLED light-emitting device is completed as described above, the anode and the cathode are connected by a known driving circuit, and the voltage, current efficiency, and device lifetime of the device are measured. The device examples and comparative examples prepared by the same method are shown in Table 3; the test results of the voltage, current efficiency, and lifetime of the obtained devices are shown in Table 4.

[0186] Table 3

[0187]

[0188]

[0189] Table 4

[0190]

[0191]

[0192] Note: The voltage, current efficiency, and emission peak were measured using an IVL (current-voltage-luminance) test system (Suzhou FushiDa Scientific Instruments Co., Ltd.); the lifetime test system was the EAS-62C OLED device lifetime tester from System Technology Research Co., Ltd. of Japan; LT95 refers to the time when the device luminance decays to 95%; all data were measured at 10 mA / cm 2 under the test.

[0193] From the device data results in Table 4, it can be seen that compared with Comparative Examples 1-3 of the device, the device lifetime of the compound of the present invention in the single-doping system device is higher than that of the comparative examples; in the single-doping system device, the device efficiency also shows good results. This is because such a boron-nitrogen fused ring parent nucleus can enhance the resonance intensity and improve the device efficiency without changing the light color; compared with Comparative Examples 4-6 of the device, in the double-doping system device using an exciton sensitizing material as the first doping, both the current efficiency and the device lifetime of the device are greatly improved compared to the OLED device of the known material, and in the double-doping device, the device efficiency is also significantly improved compared to the single-doping case.

[0194] In summary, the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A boron-containing organic compound, characterized in that, The structure of the organic compound is any one of general formulas (Ⅲ-1) to (Ⅲ-4): In general formulas (Ⅲ-1) to (Ⅲ-4), Z1 is represented as C-R6; Z2 is represented as C-R7; Z3 is represented as C-R; Each occurrence of R6, R7, and R is independently the same or different and is represented as one of a hydrogen atom and a deuterium atom; X is represented as O, S, or N(R1); R1 is represented as a substituted or unsubstituted phenyl group; R b 、R c 、R d 、R e 、R f are each independently represented by a hydrogen atom, a deuterium atom, or a substituted or unsubstituted C1-C 10 alkyl group; R a is one of a hydrogen atom, a deuterium atom, a substituted or unsubstituted C1-C 10 alkyl group, and a diphenyl-substituted triazinyl group; The substituents for the substituting groups are each independently selected from one or more of a deuterium atom, an alkyl group having 1 to 10 carbon atoms.

2. The boron-containing organic compound according to claim 1, wherein The R1 is represented as one of a phenyl group, a deuterated phenyl group, a methyl-substituted phenyl group, an ethyl-substituted phenyl group, an isopropyl-substituted phenyl group, and a tert-butyl-substituted phenyl group; The R a is respectively represented by one of a hydrogen atom, a deuterium atom, a methyl group, a deuterated methyl group, an ethyl group, a deuterated ethyl group, an isopropyl group, a deuterated isopropyl group, a tert-butyl group, a deuterated tert-butyl group, and a diphenyl-substituted triazinyl group; The R6, R7, and R are each represented as one of a hydrogen atom and a deuterium atom; The R b , R c , R d , R e , R f represents one of a hydrogen atom, a deuterium atom, a methyl group, a deuterated methyl group, an ethyl group, a deuterated ethyl group, an isopropyl group, a deuterated isopropyl group, a tert-butyl group, and a deuterated tert-butyl group, respectively.

3. A boron-containing organic compound, characterized in that, The specific structural formula of the organic compound is any one of the following structures:

4. An organic electroluminescent device includes a cathode and an anode, and an organic light-emitting functional layer therebetween, and the organic light-emitting functional layer includes a light-emitting layer, characterized in that, The light-emitting layer contains the boron-containing organic compound according to any one of claims 1-3.

5. The organic electroluminescent device according to claim 4, wherein the light-emitting layer comprises a host material and a dopant material, and the dopant material contains the boron-containing organic compound according to any one of claims 1-3.

6. The organic electroluminescent device according to claim 4, wherein the light-emitting layer comprises a first host material, a second host material, and a doping material, characterized in that At least one of the first host material and the second host material is a TADF material, and the dopant material is the boron-containing organic compound according to any one of claims 1-3.

7. The organic light-emitting device according to claim 4, wherein the light-emitting layer comprises a host material, an exciton sensitizing material, and a doping material, characterized in that The exciton sensitizing material is a metal element-containing complex, and the dopant material is the boron-containing organic compound according to any one of claims 1-3.

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