Compound taking benzene or azabenzene as core and organic electroluminescent device

Abstract

The invention relates to a compound taking benzene or azabenzene as a core and an organic electroluminescent device, and belongs to the technical field of semiconductors, the structure of the compound taking the benzene or the azabenzene as the core is shown in a general formula (1): # imgabs0 #, and the compound taking the benzene or the azabenzene as the core is applied to the organic electroluminescent device. After the compound taking benzene or azabenzene as the core is applied to the organic electroluminescent device, the device voltage is relatively low, the luminous efficiency of the device can be effectively improved, and the service life of the device can be effectively prolonged.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and particularly to a compound with benzene or azabenzene as the core and an organic electroluminescent device. Background Art

[0002] Organic electroluminescent devices (OLEDs: Organic Light Emission Diodes) can be used to manufacture new display products and new lighting products, and are expected to replace existing liquid crystal displays and fluorescent lamp lighting, with a very broad application prospect. The organic electroluminescent device has a sandwich-like structure, including electrode material layers, and organic functional materials sandwiched between different electrode material layers. Various different organic functional materials are stacked together according to their uses to jointly form an organic electroluminescent device. As a current device, when a voltage is applied to the two electrodes of the organic electroluminescent device, and positive and negative charges in the organic layer functional material layer are affected by the electric field, the positive and negative charges further recombine in the light-emitting layer, thereby generating organic electroluminescence.

[0003] Currently, organic electroluminescent display technology has been applied in the fields of smartphones, tablet computers, televisions, etc. However, compared with the actual product application requirements, the performance of organic electroluminescent devices, such as luminous efficiency and service life, still needs to be further improved. The research on improving the performance of organic electroluminescent devices includes: reducing the driving voltage of the device, increasing the luminous efficiency of the device, and increasing the service life of the device. In order to continuously improve the performance of organic electroluminescent devices, not only innovation in the structure and manufacturing process of organic electroluminescent devices is required, but also continuous research and innovation on organic functional materials to create higher-performance organic functional materials.

[0004] Blue organic electroluminescent devices have always been the weak link in the development of full-color OLEDs. So far, it has been difficult to comprehensively improve the performance of blue devices such as efficiency and lifespan. Therefore, how to improve the performance of such devices remains a crucial issue and challenge in this field. Most of the blue doping materials used in the market currently are fluorescent dopants. Due to the constraints of the quantum mechanical transition of spin conservation, the material can only utilize 25% of the singlet luminescence, while 75% of the triplet states are lost through non-radiative transition due to spin-forbidden reasons. The earliest proposed way to break through the singlet exciton limit is the concept of TTA delayed fluorescence. When the concentration of triplet excitons in the system is relatively high, two long-lived triplet excitons collide with each other, generating an excited singlet exciton and a ground-state molecule while "annihilating" each other. Theoretically, in a device based on TTA delayed fluorescence, the highest proportion of singlet exciton generation reaches 0.25 + 0.75 / 2 = 0.625. However, the exciton utilization rate of this method still cannot meet the requirements currently. How to utilize the majority of triplet luminescence is the most critical issue for improving the efficiency of organic electroluminescent devices. The spin-orbit coupling effect caused by heavy metal Pt atoms enables triplet states to emit light at room temperature. However, phosphorescent materials are not perfect either. The relatively wide bandgap of blue phosphorescence leads to a very short lifespan of blue phosphorescent devices, which is also one of the reasons restricting the further industrialization of blue phosphorescence. To solve the above problems, relevant technical personnel have been committed to improving the light-emitting layer auxiliary layer of blue phosphorescent devices in order to improve the lifespan of blue phosphorescent devices. Summary of the Invention

[0005] In view of the above problems existing in the prior art, the applicant of the present invention provides a compound with benzene or azabenzene as the core and an organic electroluminescent device. The compound of the present invention has benzene or azabenzene as the core and can improve the device efficiency and extend the lifespan by connecting specific types of branched chains at specific sites, especially the improvement of the device lifespan is very significant.

[0006] The technical solution of the present invention to solve the above technical problems is as follows: A compound with benzene or azabenzene as the core, and the structure of the compound is shown in the general formula (1):

[0007]

[0008] X1, X2, and X3 each independently represent N or CH;

[0009] R1 represents the general formula A;

[0010] When at least one of X1, X2, and X3 represents a nitrogen atom, R1 can also represent a substituted or unsubstituted C6-C 30 aryl;

[0011] M1, M2, M3, and M4 are each independently represented by any one of Formula a, Formula b, and Formula c, and at least one of M1, M2, M3, and M4 is not represented by Formula a;

[0012]

[0013] In General Formula A, Y is represented by one of N(Ra), O, or S;

[0014] In Formula c, X is represented by one of N(Rb), O, or S;

[0015] Z1, Z2, Z3, Z4, Z5, Z6, Z7, and Z8 are each independently represented by C-H or C-R;

[0016] R is selected from 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 C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group;

[0017] L and L1 are each independently represented by a direct bond, a substituted or unsubstituted C6-C 30 arylene group, a substituted or unsubstituted C2-C 30 heteroarylene group;

[0018] Ra and Rb are each independently selected from a substituted or unsubstituted C1-C 10 alkyl group, a substituted or unsubstituted C3-C 10 cycloalkyl group, a substituted or unsubstituted C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group;

[0019] The substituents for the substituent groups are each independently selected from a deuterium atom, a substituted or unsubstituted C1-C 10 alkyl group, a C3-C 10 cycloalkyl group, a C6-C 30 aryl group, a C2-C 30 heteroaryl group;

[0020] The heteroatoms in the heteroaryl group or heteroarylene group are O, N, or S;

[0021] L2, L3, L4, L5, L6, L7, L8, L9, L 10 , L 11 are represented by Formula a, Formula b, and Formula c as the linking sites of M1, M2, M3, and M4.

[0022] Further, the structure of the compound is any one of the following structures:

[0023]

[0024] Wherein, M1, M2, M3, M4, and R1 are the same as the previous definitions.

[0025] Further, the structure of the compound is any one of the following structures:

[0026]

[0027] Wherein, M1, M2, M3, M4, R1, and L1 are the same as the previous definitions.

[0028] Further, the structure of the compound is any one of the following structures:

[0029]

[0030]

[0031] Wherein, M1, M2, M3, M4, R1, and L are the same as the previous definitions.

[0032] Further, the structure of the compound is any one of the following structures:

[0033]

[0034] Wherein, M1, M2, M3, M4, R1, L, and L1 are the same as the previous definitions.

[0035] Further, R1 represents a dibenzofuranyl group substituted or unsubstituted by R, a dibenzothiophenyl group substituted or unsubstituted by R, an N-phenylcarbazolyl group substituted or unsubstituted by R; when at least one of X1, X2, and X3 represents a nitrogen atom, R1 can also represent a phenyl group substituted or unsubstituted by R0, a naphthyl group substituted or unsubstituted by R0, a biphenyl group substituted or unsubstituted by R0, a terphenyl group substituted or unsubstituted by R0, a phenanthryl group substituted or unsubstituted by R0;

[0036] R0 is arbitrarily selected from a deuterium atom, a fluorine atom, a methyl group, an ethyl group, a tert-butyl group, a phenyl group, a naphthyl group, a biphenyl group, a pyridyl group, a naphthyridinyl group, a thiophenyl group, a furanyl group, a benzothiophenyl group, a benzofuranyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a fluorenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, a carbazolyl group, or a spirofluorene group;

[0037] R is selected from a deuterium atom, a halogen atom, a methyl group, an ethyl group, a tert-butyl group, a phenyl group, a naphthyl group, a biphenyl group, a pyridyl group, a naphthyridinyl group, a thienyl group, a furyl group, a benzothienyl group, a benzofuryl group, a dibenzofuryl group, a dibenzothienyl group, a fluorenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, a carbazolyl group or a spirofluorenyl group;

[0038] Ra and Rb are each independently represented by any one of a methyl group, an ethyl group, a tert-butyl group, a phenyl group, a naphthyl group, a biphenyl group, a pyridyl group, a naphthyridinyl group, a thienyl group, a furyl group, a benzothienyl group, a benzofuryl group, a dibenzofuryl group, a dibenzothienyl group, a fluorenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, a carbazolyl group or a spirofluorenyl group;

[0039] L and L1 are each independently represented by any one of a direct bond, a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted biphenylene group, a substituted or unsubstituted pyridyl group.

[0040] Furthermore, in the general formula (1), are each independently represented by the following structures:

[0041] any one of;

[0042] wherein are not simultaneously

[0043] R1 is represented by the following structures:

[0044]

[0045] any one of;

[0046] L and L1 are each independently represented by a single bond or the following structures:

[0047] any one of. Furthermore, the specific structure of the compound is any one of the following structures:

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065] The present invention also discloses an organic electroluminescent device, comprising a cathode, an anode and a functional layer, wherein the functional layer is located between the cathode and the anode, and at least one functional layer in the organic electroluminescent device contains the compound with benzene or azabenzene as the core according to the present invention.

[0066] Further, the functional layer includes a light-emitting auxiliary layer, and the light-emitting auxiliary layer contains the compound with benzene or azabenzene as the core according to the present invention.

[0067] Further, the functional layer includes a hole transport region, a light-emitting region and an electron transport region. The hole transport region includes a hole injection layer, a hole transport layer and a light-emitting auxiliary layer, and the light-emitting auxiliary layer contains the compound with benzene or azabenzene as the core according to the present invention.

[0068] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0069] (1) The organic compound with benzene or azabenzene as the core according to the present invention has more excellent exciton blocking ability and hole mobility under high current density. When applied to a device, while improving the device efficiency, it has excellent device lifetime.

[0070] (2) The organic compound with benzene or azabenzene as the core in the present invention has a stable structure. When the hole injection becomes stronger under a high current density, holes can still be conducted to the light-emitting layer through different carrier conduction channels, ensuring the hole concentration under a high current density, and thus improving the light-emitting efficiency of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 It is a cross-sectional view of the organic electroluminescent device described in the embodiment.

[0072] In the figure, 1. Substrate layer; 2. Anode layer; 3. Hole injection layer; 4. Hole transport layer; 5. Light-emitting auxiliary layer; 6. Light-emitting layer; 7. Hole blocking layer; 8. Electron transport layer; 9. Electron injection layer; 10. Cathode layer; 11. Covering layer. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0073] The principles and features of the present invention will be described below with reference to the drawings and embodiments. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0074] In the drawings, for clarity, the dimensions of layers and regions may be exaggerated. It will also be understood that when a layer or element is referred to as being "on" another layer or substrate, the layer or element may be directly on the other layer or substrate, or an intermediate layer may also be present. In addition, it will also be understood that when a layer is referred to as being "between" two layers, the layer may be the only layer between the two layers, or one or more intermediate layers may also be present. The same reference numerals throughout the text denote the same elements.

[0075] In the present invention, when describing electrodes, organic electroluminescent devices, and other structures, the orientation words such as "upper", "lower", "top", and "bottom" are only used to represent the orientation in a certain specific state, and do not mean that the relevant structures can only exist in the described orientation; on the contrary, if the structure can be changed in position, for example, inverted, the orientation of the structure 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.

[0076] 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. According to the nature of the substrate, its usage direction is different. In the present invention, a transparent substrate is preferably used. The thickness of the substrate is not particularly limited.

[0077] An anode is formed on a substrate, and the anode can be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. When the anode 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 anode 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 anode layer depends on the material used, usually being 50 - 500 nm, preferably 70 - 300 nm, and more preferably 100 - 200 nm.

[0078] The functional layer disposed between the anode and the cathode may sequentially include a hole transport region, a light-emitting region, and an electron transport region from bottom to top.

[0079] Examples of the hole transport region constituting the organic electroluminescent device may include a hole injection layer, a hole transport layer, a light-emitting auxiliary layer, etc.

[0080] As the materials for the hole injection layer, the hole transport layer, and the light-emitting auxiliary layer, any material can be selected from the known related materials for organic electroluminescent devices for use.

[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 expect the occurrence of a 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 and conduction.

[0082] In the hole injection layer of the present invention, the ratio of the hole transport material to the P-type doping material is 99:1 - 95:5, preferably 99:1 - 97:3, based on mass.

[0083] 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.

[0084] The thickness of the hole transport layer of the present invention can be 5 - 200 nm, preferably 10 - 150 nm, but the thickness is not limited to this range.

[0085] The thickness of the light-emitting auxiliary layer of the present invention can be 1 - 50 nm, preferably 5 - 50 nm, but the thickness is not limited to this range.

[0086] The light-emitting auxiliary layer material can use a compound with benzene or azabenzene as the core represented by the general formula (1) of the present invention.

[0087] After forming the hole injection layer, the hole transport layer and the light-emitting auxiliary layer, a corresponding light-emitting layer is formed on the light-emitting auxiliary layer.

[0088] The light-emitting layer can include a host material and a doping material. The host material can use the light-emitting layer materials for organic electroluminescent devices known in the prior art; the doping material uses conventional phosphorescent materials in the art.

[0089] 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.

[0090] 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, but the thickness is not limited to this range.

[0091] In the present invention, the electron transport region can sequentially include a hole blocking layer, an electron transport layer, and an electron injection layer disposed on the light-emitting layer from bottom to top, but is not limited thereto.

[0092] 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 prolonging the life of the device and improving the performance of the device. The hole blocking layer of the present invention can be disposed on the light-emitting layer. As the hole blocking layer material of the organic electroluminescent device of the present invention, compounds having a hole blocking effect known in the prior art can be used. The thickness of the hole blocking layer of the present invention can be 2 - 200 nm, preferably 5 - 150 nm, but the thickness is not limited to this range.

[0093] The electron transport layer can be disposed on 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. A material with a high electron mobility is preferred. As the electron transport layer of the organic electroluminescent device of the present invention, the electron transport layer materials for organic electroluminescent devices known in the prior art can be used. 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.

[0094] The electron injection layer can be disposed on top of the electron transport layer. The material of the electron injection layer is generally preferably a material having 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, 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 can 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.

[0095] The cathode can be disposed on top of the electron transport region. The cathode can be a transmissive electrode, a semi-transmissive electrode or a reflective electrode. When the cathode is a transmissive electrode, the cathode can include, for example, Li, Yb, Ca, LiF / Ca, LiF / Al, Al, Mg, BaF, Ba, Ag or a compound or mixture thereof; when the cathode is a semi-transmissive electrode or a reflective electrode, the cathode can 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.

[0096] In order to improve the light extraction efficiency of the organic electroluminescent device, a light extraction layer (i.e., a CPL layer, also referred to as a cover layer) can also be added on the cathode of the device. Any material known in the art can be used as the CPL layer material. The thickness of the CPL cover layer is generally 5 - 300 nm, preferably 20 - 100 nm and more preferably 40 - 80 nm.

[0097] The organic electroluminescent device of the present invention can also include a packaging structure. The packaging structure can 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 can 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, a light-emitting auxiliary layer, an organic film layer, an electron transport layer, an electron injection layer and a cathode on a substrate, and optionally a cover layer. In this regard, methods such as vacuum deposition, vacuum evaporation, spin coating, casting, LB method, inkjet printing, laser printing or LITI can be used, but are not limited thereto. In the present invention, vacuum evaporation is preferably used to form each of the layers. Those skilled in the art can conventionally select each process condition in the vacuum evaporation method according to actual needs.

[0099] Preparation Examples

[0100] Synthesis of Intermediate B-3:

[0101]

[0102] In a three-necked flask, under nitrogen protection, 12 mmol (3.82 g) of starting material Z-1 and 10 mmol (2.48 g) of starting material W-1 were dissolved in tetrahydrofuran (THF), and then 0.1 mmol (0.12 g) of Pd(PPh3)4 and 50 mL of a 3 mol / L aqueous solution of K2CO3 were added. The mixture was heated under reflux for 14 hours. Samples were taken for TLC to confirm the completion of the reaction. After cooling to room temperature, the reaction mixture was filtered through a pad of diatomaceous earth, rinsed with chloroform, and the resulting filtrate was evaporated in vacuo. The obtained residue was purified by column chromatography on silica gel using hexane / toluene as the eluent to give Intermediate B-3.

[0103] Other Intermediates B were prepared in a similar manner to the synthesis of Intermediate B-3 as shown in Table 1 below:

[0104] Table 1

[0105]

[0106] Synthesis of Intermediate C-1:

[0107]

[0108] In a three-necked flask, under nitrogen protection, 10 mmol (1.67 g) of starting material A-1 and 13 mmol (4.12 g) of starting material Z-5 were added to the three-necked flask and dissolved in 150 mL of toluene. Then 30 mmol (3.37 g) of potassium tert-butoxide, 0.5 mmol (0.46 g) of Pd2(dba)3, and 1.5 mmol (0.11 g) of trimethylphosphine were added. The mixture was heated under reflux for 12 hours under nitrogen protection. Samples were taken for TLC to confirm the completion of the reaction. After cooling to room temperature, the mixture was filtered and the filtrate was rotary evaporated until no more distillate was obtained. The obtained residue was purified by column chromatography on silica gel to give Intermediate C-1.

[0109] Intermediates C were prepared in a similar manner to the synthesis of Intermediate C-1 as shown in Table 2 below:

[0110] Table 2

[0111]

[0112]

[0113]

[0114] Synthesis of Intermediate E-1:

[0115]

[0116] In a three-necked flask, under nitrogen protection, 15 mmol (5.36 g) of intermediate C-2 and 12 mmol (3.99 g) of raw material A-5 were added to the three-necked flask, dissolved in 150 mL of toluene, then 35 mmol (3.93 g) of potassium tert-butoxide, 0.45 mmol (0.41 g) of Pd2(dba)3, and 5 mmol (0.38 g) of trimethylphosphine were added. The reaction was heated to reflux under nitrogen protection for 18 hours. Samples were taken for TLC to confirm the completion of the reaction. After cooling to room temperature, the mixture was filtered, and the filtrate was rotary evaporated until no distillate was obtained. The residue obtained was purified by column chromatography on silica gel to obtain intermediate E-1.

[0117] Intermediate E was prepared in a method similar to that in the synthesis of intermediate E-1, as shown in Table 3 below:

[0118] Table 3

[0119]

[0120]

[0121]

[0122] Synthesis of intermediate E-10:

[0123]

[0124] Under nitrogen protection, intermediate C-6 (12 mmol, 5.55 g) and cesium carbonate (54 mmol, 17.59 g) were added to a three-necked flask, 120 mL of anhydrous DMF was added, and the mixture was stirred at room temperature for 25 minutes. Raw material A-2 (10 mmol, 2.57 g) was further added to the reaction mixture, and the mixture was stirred and refluxed for 20 hours. After cooling, filtering, washing with water, drying, and purification by silica gel column chromatography, intermediate E-10 was obtained.

[0125] Intermediate E was prepared in a method similar to that in the synthesis of intermediate E-10, as shown in Table 4 below:

[0126] Table 4

[0127]

[0128] Example 1: Synthesis of compound 13:

[0129]

[0130] In a three-necked flask, under nitrogen protection, 15 mmol (9.13 g) of intermediate E-1 and 20 mmol (2.44 g) of raw material D-1 were added to the three-necked flask, dissolved in tetrahydrofuran (THF), then 0.1 mmol (0.12 g) of Pd(PPh3)4 and 60 mL of 3 mol / L aqueous K2CO3 solution were added, and the reaction was heated under reflux for 17 hours under nitrogen protection. Samples were taken for TLC to confirm the completion of the reaction. After cooling to room temperature, the reaction mixture was filtered through a pad of diatomaceous earth, rinsed with chloroform, and the resulting filtrate was evaporated in vacuo. The residue obtained was purified by column chromatography on silica gel using hexane / toluene as the eluent to give compound 13. Elemental analysis for C 47 H 30 N4 theoretical values: C, 86.74; H, 4.65; N, 8.61; found values: C, 86.73; H, 4.60; N, 8.63. LC-MS: found value: 651.18 ([M+H] + ), exact mass: 650.25.

[0131] The following target compounds were synthesized with reference to the preparation process of Example 1; the reaction conditions were the same, except that the intermediates E and raw materials D listed in Table 5 below were used:

[0132] Table 5

[0133]

[0134]

[0135]

[0136] Device Examples and Device Comparative Examples

[0137] Device Comparative Example 1

[0138] The specific preparation process is as follows:

[0139] As Figure 1As shown, an anode layer 2 (Ag (100 nm)) is provided on a substrate layer 1. On the anode layer 2, using a vacuum evaporation device, HT1 and HI1 with a film thickness of 10 nm are evaporated as a hole injection layer 3, and the mass ratio of HT1 and HI1 is 97:3. Then, HT1 with a thickness of 120 nm is evaporated as a hole transport layer 4. Subsequently, EB-1 with a thickness of 5 nm is evaporated as a light-emitting auxiliary layer 5. After the evaporation of the above light-emitting auxiliary material is completed, a light-emitting layer 6 of an organic electroluminescent device is fabricated. Its structure includes BH1 and BH2 used as host materials and BD1 used as a doping material in the light-emitting layer 6, and the ratio of the three is 60%:26%:14% by weight, and the film thickness of the light-emitting layer 6 is 35 nm. After the above light-emitting layer 6, BH2 is continuously evaporated with a film thickness of 5 nm as a hole blocking layer 7. On the above hole blocking layer 7, ET-1 and LiQ are continuously evaporated, and the mass ratio of ET-1 and LiQ is 1:1, and the vacuum evaporation film thickness of this material is 30 nm, and this layer is an electron transport layer 8. On the electron transport layer 8, a LiF layer with a film thickness of 1 nm is fabricated by a vacuum evaporation device, and this layer is an electron injection layer 9. On the electron injection layer 9, a Mg:Ag electrode layer with a film thickness of 16 nm is fabricated by a vacuum evaporation device, and the mass ratio of Mg and Ag is 1:9, and this layer is used as a cathode layer 10. On the cathode layer 10, 65 nm of CP-1 is vacuum-evaporated as a cover layer 11.

[0140] The preparation method of Device Examples 1-14 is the same as that of Device Comparative Example 1, except that the organic material of the light-emitting auxiliary layer uses the organic compound with benzene or azabenzene as the core described in the present invention. The preparation methods of Device Comparative Examples 2-7 are the same as that of Device Comparative Example 1, except that the organic materials of the light-emitting auxiliary layer use comparative compounds EB-2, EB-3, EB-4, EB-5, EB-6, and EB-7. The specific structures of Device Examples 1-14 and Device Comparative Examples 1-7 are shown in Table 6.

[0141] The molecular structural formulas of the related materials are as follows: The molecular structural formulas of the related materials are as follows:

[0142]

[0143]

[0144] 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 lifetime of the device are measured. Device Examples 1-14 and Comparative Examples 2-7 prepared by the same method are shown in Table 6; the test results of the voltage, current efficiency, and LT70 lifetime at 1000 nits of the obtained devices are shown in Table 7.

[0145] Table 6

[0146]

[0147]

[0148]

[0149] Table 7

[0150]

[0151]

[0152] Note: LT70 refers to the time when the device brightness decays to 70% of the original brightness under the current density condition corresponding to a brightness of 1000 nits.

[0153] The current efficiency and driving voltage were measured using an IVL (current-voltage-brightness) test system (Suzhou FushiDa Scientific Instrument Co., Ltd.); the current density was 10 mA / cm 2 ;

[0154] The lifetime test system was the EAS-62C type OLED lifetime test system of System Science Co., Ltd. of Japan.

[0155] It can be seen from the data in Table 7 above that applying the organic compound with benzene or azabenzene as the core described in the present invention in the light-emitting auxiliary layer of an organic electroluminescent device can reduce the driving voltage, improve the current efficiency, and significantly extend the service life. In the structure of the organic compound with benzene or azabenzene as the core, substitution occurs at the meta- and para-positions, and the substituent groups are mainly carbazole groups. Therefore, the compound of the present invention application has more excellent exciton blocking ability and hole mobility at high current density. When applied to a device, it has excellent device lifetime while improving the device efficiency.

[0156] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, all possible combinations of the technical features in the above embodiments are not exhaustively listed. However, as long as there is no contradiction in the combination of these technical features, it should be considered as falling within the scope described in this specification.

[0157] For those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. The protection scope of the present invention is subject to the appended claims.

Claims

1. A compound with benzene or azabenzene as the core, characterized in that, The structure of the said compound is as shown in general formula (1): X1, X2, and X3 each independently represent N or CH; R1 represents general formula A; When at least one of X1, X2, and X3 represents a nitrogen atom, R1 can also represent a substituted or unsubstituted C6-C 30 aryl; M1, M2, M3, and M4 each independently represent any one of formula a, formula b, and formula c, and at least one of M1, M2, M3, and M4 does not represent formula a; In general formula A, Y represents one of N(Ra), O, or S; In formula c, X represents one of N(Rb), O, or S; Z1, Z2, Z3, Z4, Z5, Z6, Z7, and Z8 each independently represent C-H or C-R; R is selected from 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 C6-C 30 aryl group, a substituted or unsubstituted C2-C 30 heteroaryl group; The L and L1 each independently represent a direct bond, a substituted or unsubstituted C6-C 30 arylene group, a substituted or unsubstituted C2-C 30 heteroarylene group; Ra and Rb are each independently selected from any one of substituted or unsubstituted C1-C 10 alkyl, substituted or unsubstituted C3-C 10 cycloalkyl, substituted or unsubstituted C6-C 30 aryl, substituted or unsubstituted C2-C 30 heteroaryl; The substituents for the substitutable groups are each independently selected from one or more of a deuterium atom, a substituted or unsubstituted C1-C 10 alkyl group, a C3-C 10 cycloalkyl group, a C6-C 30 aryl group, a C2-C 30 heteroaryl group; The heteroatom in the said heteroaryl or heteroarylene is O, N, or S; The L2, L3, L4, L5, L6, L7, L8, L9, L 10 、L 11 are represented as Formula a, Formula b, and Formula c as the connection sites of M1, M2, M3, and M4.

2. The compound with benzene or azabenzene as the core according to claim 1, characterized in that, The structure of the said compound is any one of the following structures: Wherein, M1, M2, M3, M4, and R1 are the same as defined in claim 1.

3. A compound with benzene or azabenzene as the core according to claim 1, characterized in that, The structure of the said compound is any one of the following structures: Wherein, M1, M2, M3, M4, R1, and L1 are the same as defined in claim 1.

4. A compound with benzene or azabenzene as the core according to claim 1, characterized in that, The structure of the said compound is any one of the following structures: Wherein, M1, M2, M3, M4, R1, and L are the same as defined in claim 1.

5. A compound with benzene or azabenzene as the core according to claim 1, characterized in that, The structure of the said compound is any one of the following structures: Wherein, M1, M2, M3, M4, R1, L, and L1 are the same as defined in claim 1.

6. A compound with benzene or azabenzene as the core according to any one of claims 1-5, characterized in that, The said R1 represents a dibenzofuranyl group substituted or unsubstituted by R, a dibenzothiophenyl group substituted or unsubstituted by R, an N-phenylcarbazolyl group substituted or unsubstituted by R; when at least one of X1, X2, and X3 represents a nitrogen atom, the said R1 may also represent a phenyl group substituted or unsubstituted by R0, a naphthyl group substituted or unsubstituted by R0, a biphenyl group substituted or unsubstituted by R0, a terphenyl group substituted or unsubstituted by R0, a phenanthryl group substituted or unsubstituted by R0; The said R0 is arbitrarily selected from a deuterium atom, a fluorine atom, a methyl group, an ethyl group, a tert-butyl group, a phenyl group, a naphthyl group, a biphenyl group, a pyridyl group, a naphthyridinyl group, a thiophenyl group, a furyl group, a benzothiophenyl group, a benzofuranyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a fluorenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, a carbazolyl group, or a spirofluorenyl group; The said R is arbitrarily selected from a deuterium atom, a halogen atom, a methyl group, an ethyl group, a tert-butyl group, a phenyl group, a naphthyl group, a biphenyl group, a pyridyl group, a naphthyridinyl group, a thiophenyl group, a furyl group, a benzothiophenyl group, a benzofuranyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a fluorenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, a carbazolyl group, or a spirofluorenyl group; The said Ra and Rb each independently represent any one of a methyl group, an ethyl group, a tert-butyl group, a phenyl group, a naphthyl group, a biphenyl group, a pyridyl group, a naphthyridinyl group, a thiophenyl group, a furyl group, a benzothiophenyl group, a benzofuranyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a fluorenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, a carbazolyl group, or a spirofluorenyl group; The said L and L1 each independently represent a direct bond, a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted biphenylene group, or a substituted or unsubstituted pyridyl group.

7. A compound with benzene or azabenzene as the core according to any one of claims 1-5, characterized in that In the general formula (1), are each independently represented by the following structures: any one of; wherein not simultaneously The R1 is represented by the following structure: any one of; The said L and L1 each independently represent a single bond or the following structure: any one of 8. A compound with benzene or azabenzene as the core according to claim 1, characterized in that, The specific structure of the said compound is any one of the following structures:

9. An organic electroluminescent device, comprising a cathode, an anode, and a functional layer, the functional layer being located between the cathode and the anode, characterized in that, At least one functional layer in the organic electroluminescent device contains the compound with benzene or azabenzene as the core according to any one of claims 1 to 8.

10. An organic electroluminescent device according to claim 9, characterized in that, The functional layer includes a hole transport region, a light-emitting region, and an electron transport region. The hole transport region includes a hole injection layer, a hole transport layer, and a light-emitting auxiliary layer, and the light-emitting auxiliary layer contains the compound with benzene or azabenzene as the core according to any one of claims 1 to 8.

Images