A compound containing a phenanthroline structure and an OLED light-emitting device comprising the same

Abstract

The present invention discloses a phenanthroline-containing compound and an organic electroluminescent device comprising the same, belonging to the technical field of semiconductor materials. The structure of the compound of the present invention is shown in general formula (1). By introducing a specific bridging mode between two phenanthroline structural units, the formed compound has characteristics such as a high glass transition temperature and molecular thermal stability, good electron mobility, a low evaporation temperature, and appropriate HOMO / LUMO energy levels. When the compound of the present invention is used as a material for an organic electroluminescent device, good efficiency and lifespan can be achieved at a low driving voltage.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor materials, and in particular to an organic compound containing a 1,10-phenanthroline structure, a single-layer OLED light-emitting device and an OLED stacked light-emitting device prepared therefrom. Background Art

[0002] The technology of organic light-emitting diodes (OLEDs) can be used to manufacture new display products and new lighting products, and is expected to replace existing liquid crystal displays and fluorescent lamp lighting, with a very broad application prospect. The OLED light-emitting device has a sandwich structure, including electrode material layers and organic functional materials sandwiched between different electrode layers. Various different functional materials are stacked together according to their uses to jointly form an OLED light-emitting device. As a current device, when a voltage is applied to the two electrodes of the OLED light-emitting 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, that is, OLED electroluminescence is generated.

[0003] At present, OLED display technology has been applied in the fields of smart phones, tablet computers, etc., and will further expand to large-size application fields such as televisions. However, compared with the actual product application requirements, the performance of OLED devices such as luminous efficiency and service life still needs to be further improved. Currently, the research on improving the performance of OLED light-emitting devices includes: reducing the driving voltage of the device, improving the luminous efficiency of the device, improving the service life of the device, etc. In order to continuously improve the performance of OLED devices, it is necessary not only to innovate the OLED device structure and manufacturing process, but also to continuously research and innovate OLED optoelectronic functional materials to create higher-performance OLED functional materials.

[0004] OLED optoelectronic functional materials applied to OLED devices can be classified into two categories according to their uses, namely charge injection and transport materials and light-emitting materials. Further, the charge injection and transport materials can be divided into electron injection and transport materials, electron blocking materials, hole injection and transport materials, and hole blocking materials. As charge transport materials, they are required to have good carrier mobility, high glass transition temperature, etc. For OLED devices, electrons are injected from the cathode and then transferred to the host material through the electron transport layer, and recombine with holes in the host material to generate excitons. Therefore, improving the injection ability and transport ability of the electron transport layer is beneficial to reducing the driving voltage of the device and obtaining high-efficiency electron-hole recombination efficiency.

[0005] In addition, in a stacked OLED, the stacked OLED is formed by connecting two or more independent light-emitting units in series through a charge generation layer (CGL). Under the action of an external electric field, the electrons and holes generated by the CGL are respectively injected into adjacent light-emitting units, and excitons are recombined in the light-emitting units to emit light. Therefore, the material selection and design of the CGL are key factors affecting the optoelectronic performance and lifespan of the stacked OLED. The CGL layer is constructed in a p-n structure form, where the p-type material mainly generates holes, such as materials like F4-TCNQ and HAT-CN, while the n-type doped material is obtained by doping a low work function metal into an electron transport layer material, such as Alq3:Mg and Bphen:Li, etc. Therefore, the performance of the electron transport material of the n-type doped material in the CGL has a very great impact on the device performance. It is required to have efficient electron injection ability, transport ability, and high electron durability. At the same time, the heat resistance and film stability of the material are also important. Materials with low heat resistance are not only prone to decomposition during material evaporation, but also thermal decomposition will occur due to the heat generated by the device during device operation, leading to material deterioration. When the phase stability of the material film is poor, the material also undergoes thin film crystallization in a short time, resulting in direct layer separation of the organic film layer and device deterioration. Therefore, the materials used are required to have high heat resistance and good film stability.

[0006] With the remarkable progress of OLED devices, the required performance of materials is also increasing day by day. It is not only required to have good material stability, but also to achieve good efficiency and lifespan at low driving voltages. Summary of the Invention

[0007] In view of the above problems existing in the prior art, the present invention provides a compound containing a phenanthroline structure and an OLED light-emitting device comprising the same. In the compound of the present invention, 1,10-phenanthroline is connected through a specific bridging group, and this type of compound can effectively reduce the device driving voltage and improve the device operating lifespan.

[0008] The technical solution provided by the present invention is as follows:

[0009] A compound containing a phenanthroline structure, the structure of the compound is shown as general formula (1):

[0010]

[0011] In general formula (1), L represents a structure shown as general formula (C-1), general formula (C-2), general formula (C-3), general formula (C-4), general formula (C-5), general formula (C-6), general formula (C-7), general formula (C-8), general formula (C-9) or general formula (C-10); Ar 1 、Ar 2 each independently represents a structure of general formula (2), Ar 1Same as or different from Ar 2 Same or different;

[0012] In general formula (2), L 0 Represents a single bond or a phenylene group; R 1 Represents a hydrogen atom or a phenyl group.

[0013] Preferably, the structure of the compound is as shown in any one of general formulas (1-1) to (1-9):

[0014]

[0015] The definitions of Ar1 and Ar2 are the same as those defined above.

[0016] Preferably, the structure of the compound is as shown in any one of general formulas (2-1) to (2-9):

[0017]

[0018] Ar 1 and Ar 2 Have the same meanings as those defined above.

[0019] Preferably, general formula (2) is represented by any one of the following structures:

[0020]

[0021] Preferably, the specific structure of the compound is any one of the following structures:

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042] An OLED light-emitting device includes a first electrode, a second electrode, and an organic functional layer. The organic functional layer is located between the first electrode and the second electrode. The organic functional layer includes a hole transport layer, a light-emitting layer, and an electron transport layer. The light-emitting layer is located between the hole transport layer and the electron transport layer. The electron transport layer contains the compound containing a phenanthroline structure.

[0043] An OLED stacked light-emitting device includes a first electrode, a second electrode, a first light-emitting unit, a second light-emitting unit, and a charge generation layer. The first light-emitting unit, the second light-emitting unit, and the charge generation layer are located between the first electrode and the second electrode. The charge generation layer is located between the first light-emitting unit and the second light-emitting unit. The charge generation layer contains the compound containing a phenanthroline structure.

[0044] Preferably, the first light-emitting unit includes a hole transport region, a light-emitting layer, and an electron transport region. The second light-emitting unit includes a hole transport region, a light-emitting layer, and an electron transport region.

[0045] Preferably, the charge generation layer further contains a metal material.

[0046] More preferably, the metal material is Li, Ca, Ag, Cs, or Yb.

[0047] The beneficial technical effects of the present invention are as follows:

[0048] (1) In the compound of the present invention, 1,10-phenanthroline is connected on both sides through a specific bridging group (biphenyl or terphenyl), which can effectively improve electron injection and transport, increase the electron mobility, and thus reduce the device driving voltage.

[0049] (2) By introducing a specific bridging group (biphenyl or terphenyl) between the 1,10-phenanthrolines in the compounds of the present invention, the film crystallinity of the molecules can be inhibited, the film stability and heat resistance durability of the materials can be improved, which is beneficial to improving the device efficiency and lifespan.

[0050] (3) Further, due to the good electron-withdrawing ability, film stability and electron tolerance of the compounds of the present invention, when used as the n-type material of the CGL layer, they can form stable N-metal coordination bonds with metals such as Li or Yb, forming a stable and flat organic-metal doped film, inhibiting the oxidation of the metal, which is beneficial to improving the charge generation efficiency and device stability.

[0051] (4) After the compounds of the present invention are applied as the materials of the organic electroluminescent functional layer in OLED devices, they can effectively reduce the driving voltage of the devices, improve the device lifespan, have good application effects in OLED light-emitting devices, and have good industrialization prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 is a schematic structural diagram of the materials listed in the present invention applied to a single-layer OLED device;

[0053] In the figure: 1. Substrate; 2. Anode; 3. Hole injection layer; 4. Hole transport layer; 5. Electron blocking layer; 6. Light-emitting layer; 7. Hole blocking layer; 8. Electron transport layer; 9. Electron injection layer; 10. Cathode;

[0054] Figure 2 is a schematic structural diagram of the materials listed in the present invention applied to a stacked OLED device;

[0055] In the figure: 1. Substrate; 2. First electrode layer; 3. Hole injection layer; 4. Hole transport layer; 5. Electron blocking layer; 6. Light-emitting layer; 7. Hole blocking layer; 8. Electron transport layer; 9. Charge generation layer (CGL layer); 10. Hole transport layer; 11. Electron blocking layer; 12. Light-emitting layer; 13. Hole blocking layer; 14. Electron transport layer; 15. Electron injection layer; 16. Second electrode layer.

[0056] The first light-emitting unit is composed of 3. Hole injection layer; 4. Hole transport layer; 5. Electron blocking layer; 6. Light-emitting layer; 7. Hole blocking layer; 8. Electron transport layer, and the second light-emitting unit is composed of 10. Hole transport layer; 11. Electron blocking layer; 12. Light-emitting layer; 13. Hole blocking layer; 14. Electron transport layer; 15. Electron injection layer. DETAILED DESCRIPTION OF THE INVENTION

[0057] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Without conflict, the embodiments and features in the embodiments of the present invention may be combined with each other. The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but it is not intended to limit the present invention.

[0058] In the present invention, unless otherwise specified, HOMO means the highest occupied molecular orbital, and LUMO means the lowest unoccupied molecular orbital. In addition, in the present invention, the HOMO and LUMO energy levels are represented by absolute values, and the comparison between energy levels is also the comparison of the magnitudes of their absolute values. Those skilled in the art know that the larger the absolute value of the energy level, the lower the energy of the energy level.

[0059] 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.

[0060] In the present invention, when describing electrodes, organic electroluminescent devices, and other structures, terms indicating directions such as "upper", "lower", "top", and "bottom" are only used to indicate the directions in a specific state, and do not mean that the relevant structures can only exist in the stated directions; on the contrary, if the structure can be transformed in position, such as being inverted, the directions 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 away from the substrate is the "top" and "upper" sides.

[0061] Organic electroluminescent device

[0062] The present invention provides an OLED light-emitting device, including a first electrode, a second electrode, and an organic functional layer. The organic functional layer is located between the first electrode and the second electrode. The organic functional layer includes a hole transport layer, a light-emitting layer, and an electron transport layer. The light-emitting layer is located between the hole transport layer and the electron transport layer. The electron transport layer contains the compound represented by the general formula (1).

[0063] The present invention provides an OLED stacked light-emitting device, including a first electrode, a second electrode, a first light-emitting unit, a second light-emitting unit, and a charge generation layer. The first light-emitting unit, the second light-emitting unit, and the charge generation layer are located between the first electrode and the second electrode. The charge generation layer is located between the first light-emitting unit and the second light-emitting unit. The charge generation layer contains the compound represented by the general formula (1).

[0064] In a preferred embodiment, the first light-emitting unit includes a hole transport region, a light-emitting layer, and an electron transport region, and the second light-emitting unit includes a hole transport region, a light-emitting layer, and an electron transport region. In a preferred embodiment, the charge generation layer further includes a metal material. In a preferred embodiment, the metal material is Li, Ca, Ag, Cs, or Yb.

[0065] 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.

[0066] A first electrode is formed on the substrate, and the first electrode and the second electrode can face 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.

[0067] The organic functional material layer disposed between the first electrode and the second electrode includes a hole transport region, a light-emitting layer, and an electron transport region in sequence from bottom to top.

[0068] 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.

[0069] As the materials for the hole injection layer, the hole transport layer, and the electron blocking layer, any material can be selected from known related materials for OLED devices for use.

[0070] Examples of the above materials may include 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 quinolone derivatives, styryl anthracene derivatives, styrylamine derivatives, and other styrene compounds such as fluorene derivatives, spirofluorene derivatives, silazane derivatives, aniline copolymers, porphyrin compounds, carbazole derivatives, polyarylalkane derivatives, polyphenylene vinylene 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.

[0071] 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-mentioned hole carrier conduction film layers with different functions, their film thicknesses are not particularly limited.

[0072] 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 very 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 conduction.

[0073] In view of the above empirical summaries, for hole-type host materials with different HOMO energy levels, different P-doping materials need to be selected to match them in order to achieve ohmic contact at the interface and improve the hole injection effect.

[0074] Thus, in one embodiment of the present invention, in order to better inject holes, the hole injection layer further comprises a P-type doping material with charge conductivity 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-tris(methylene(cyanocarbonylimino)))tris(2,3,5,6-tetrafluorobenzyl); or metal oxides such as tungsten oxide and molybdenum oxide, but not limited thereto.

[0075] In the hole injection layer of the present invention, the ratio of the hole transport material to the P-type doping material used is 99:1 - 95:5, preferably 99:1 - 97:3, by mass.

[0076] 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.

[0077] 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.

[0078] The thickness of the electron blocking layer of the present invention can be 1 - 20 nm, preferably 5 - 10 nm, but the thickness is not limited to this range.

[0079] 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.

[0080] The light-emitting layer may comprise a host material and a doping material. The host material can be selected from any of the known relevant materials for OLED devices for use, and the doping material can be selected from any of the known relevant materials for OLED devices for use.

[0081] In the light-emitting layer of the present invention, the ratio of the host material to the guest material used is 99:1 - 70:30, preferably 99:1 - 85:15, and more preferably 97:3 - 87:13, by mass.

[0082] The thickness of the light-emitting layer can be adjusted to optimize the light-emitting efficiency and the driving voltage. The preferred thickness range is 5 nm to 50 nm, further preferably 10 - 50 nm, and more preferably 15 - 30 nm, but the thickness is not limited to this range.

[0083] 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 provided above the light-emitting layer, but is not limited thereto.

[0084] 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 lifespan of the device and improving the efficiency of the device. The hole blocking layer of the present invention may be provided 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 having a hole blocking effect 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. The thickness of the hole blocking layer of the present invention may be 2 - 200 nm, preferably 5 - 150 nm, and more preferably 10 - 100 nm, but the thickness is not limited to this range.

[0085] The electron transport layer may be provided above the light-emitting layer or (if present) the hole blocking layer.

[0086] The thickness of the electron transport layer of the present invention may be 10 - 80 nm, preferably 20 - 60 nm, and more preferably 25 - 45 nm, but the thickness is not limited to this range.

[0087] The electron injection layer may be provided above the electron transport layer. The electron injection layer material 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 electron injection layer material of the organic electroluminescent device of the present invention, electron injection layer materials known in the prior art for 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.

[0088] The second electrode may be disposed over 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.

[0089] The organic light-emitting 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 light-emitting 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.

[0090] A method for preparing the organic light-emitting 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 on a substrate, and optionally a covering layer. 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 of the layers. Those skilled in the art can conventionally select each process condition in the vacuum evaporation method according to actual needs.

[0091] 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;

[0092] Synthesis of intermediates N1, L1, and P1:

[0093]

[0094] Under nitrogen protection, in a 500 ml round-bottom flask, successively add raw material A1 (7.77 g, 30 mmol), bis(pinacolato)diboron (8.38 g, 33 mmol, CAS: 73183-34-3), KOAC (8.83 g, 90 mmol), dioxane (200 mL), purge with nitrogen for 30 min to displace air, and add Pd(PPh 3 ) 4(0.6 mmol), heated under reflux for 10 h under nitrogen protection. The reaction solution was taken for TLC detection and it was found that raw material A1 had completely reacted. After the reaction was completed, the reaction system was naturally cooled to room temperature, poured into a separatory funnel, shaken, and then allowed to stand for phase separation. After liquid separation, the aqueous phase was extracted with dichloromethane (50 ml × 3). The organic phases were combined, dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by rotary evaporation to remove dichloromethane to obtain intermediate N1. LC-MS: Measured value: 307.24 ([M + H] + ); Exact mass: 306.15.

[0095] In a 250 ml three-necked flask, 20 mmol of raw material A1 (5.18 g), 22 mmol of m-chlorophenylboronic acid (3.44 g), 50 ml of toluene, 50 ml of ethanol, 50 ml of water, 0.04 mmol of tetrakis(triphenylphosphine)palladium(0) (0.05 g), and 60 mmol of sodium carbonate (6.36 g) were added. The flask was purged with nitrogen for 10 minutes. Then, mechanical stirring was carried out, and the temperature was raised to reflux and the reaction was maintained for 12 hours. Then, TLC was used to check the reaction, and it was confirmed that raw material A1 had completely reacted, and the reaction mixture was naturally cooled to room temperature. The reaction liquid was extracted twice with 50 ml of ethyl acetate. The organic phases were combined, dried over anhydrous magnesium sulfate, concentrated by rotary evaporation, and passed through a silica gel column with an eluent of toluene:petroleum ether = 1:3. The filtrate was concentrated by rotary evaporation to obtain intermediate L1. LC-MS: Measured value: 291.28 ([M + H] + ); Exact mass 290.06.

[0096] Under nitrogen protection, in a 500 ml round-bottomed flask, intermediate L1 (5.82 g, 20 mmol), bis(pinacolato)diboron (6.09 g, 24 mmol, CAS: 73183-34-3), KOAC (5.89 g, 60 mmol), and dioxane (200 mL) were successively added. The flask was purged with nitrogen for 30 min to displace air, and Pd(PPh 3 ) 4 (0.46 g, 0.4 mmol) was added. The reaction mixture was heated under reflux for 14 h under nitrogen protection. The reaction solution was taken for TLC detection and it was found that intermediate L1 had completely reacted. After the reaction was completed, the reaction system was naturally cooled to room temperature, poured into a separatory funnel, shaken, and then allowed to stand for phase separation. After liquid separation, the aqueous phase was extracted with dichloromethane (50 ml × 3). The organic phases were combined, dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by rotary evaporation to remove dichloromethane to obtain intermediate P1. LC-MS: Measured value: 383.32 ([M + H] + ); Exact mass 382.19.

[0097] Intermediate N was prepared by a synthesis method similar to that of intermediate N1, and the raw materials used are shown in Table 1;

[0098] Intermediate L was prepared by a synthesis method similar to that of intermediate L1, and the raw materials used are shown in Table 1;

[0099] The intermediate P is prepared by a synthesis method similar to that of intermediate P1, and the intermediates used are shown in Table 1;

[0100] Table 1

[0101]

[0102] Mass spectrometry data of intermediate N1: LC-MS: Measured value: 307.25 ([M+H] + ); Exact mass 306.15.

[0103] Mass spectrometry data of intermediate N2: LC-MS: Measured value: 307.31 ([M+H] + ); Exact mass 306.15.

[0104] Mass spectrometry data of intermediate N3: LC-MS: Measured value: 307.20 ([M+H] +) ; Exact mass 306.15.

[0105] Mass spectrometry data of intermediate N4: LC-MS: Measured value: 383.26 ([M+H] + ); Exact mass 382.19.

[0106] Mass spectrometry data of intermediate N5: LC-MS: Measured value: 383.12 ([M+H] + ); Exact mass 382.19.

[0107] Mass spectrometry data of intermediate N6: LC-MS: Measured value: 307.09 ([M+H] + ); Exact mass 306.15.

[0108] Mass spectrometry data of intermediate L1: LC-MS: Measured value: 291.28 ([M+H] + ); Exact mass 290.06.

[0109] Mass spectrometry data of intermediate L2: LC-MS: Measured value: 291.15 ([M+H] + ); Exact mass 290.06.

[0110] Mass spectrometry data of intermediate L3: LC-MS: Measured value: 291.03 ([M+H] + ); Exact mass 290.06.

[0111] Mass spectrometry data of intermediate L4: LC-MS: Measured value: 367.14 ([M+H] + ); Exact mass 366.09.

[0112] Mass spectrometry data of intermediate L5: LC-MS: Measured value: 367.06 ([M+H] + ); Exact mass 366.09.

[0113] Preparation of intermediate M1 and intermediate Q1:

[0114]

[0115] Under nitrogen protection, in a 500 ml round-bottom flask, successively add raw material B1 (9.52 g, 30 mmol), phenylboronic acid (3.66 g, 30 mmol), K 2 CO 3 (12.44 g, 90 mmol), tetrahydrofuran (180 mL), water (60 mL), purge with nitrogen for 30 min to displace air, add Pd(PPh 3 ) 4 (0.693 g, 0.6 mmol), and heat under reflux for 15 h under nitrogen protection. Take a TLC test of the reaction solution and find that raw material B1 has completely reacted. After the reaction is completed, naturally cool the reaction system to room temperature, rotary evaporate to remove the solvent, dissolve the residue in 150 ml of dichloromethane, wash with 100 ml of water, pour it into a separatory funnel, shake and let it stand for liquid separation. After liquid separation, extract the aqueous phase with dichloromethane (50 ml * 3). Combine the organic phases, dry with anhydrous magnesium sulfate, filter, rotary evaporate the filtrate to remove dichloromethane to obtain a crude product, and purify the crude product by silica gel column chromatography to obtain intermediate M1. LC-MS: Measured value: 266.91 ([M+H] + ); Exact mass: 265.95.

[0116] Under nitrogen protection, in a 500 ml round-bottom flask, successively add intermediate N1 (6.74 g, 22 mmol), intermediate M1 (5.89 g, 22 mmol), K 2 CO 3 (8.29 g, 60 mmol), tetrahydrofuran (180 mL), water (60 mL), purge with nitrogen for 30 min to displace air, add Pd(PPh 3 ) 4 (0.46 g, 0.4 mmol), and heat under reflux for 14 h under nitrogen protection. Take a TLC test of the reaction solution and find that intermediate N1 has completely reacted. After the reaction is completed, naturally cool the reaction system to room temperature, rotary evaporate to remove the solvent, dissolve the residue in 150 ml of dichloromethane, wash with 100 ml of water, pour it into a separatory funnel, shake and let it stand for liquid separation. After liquid separation, extract the aqueous phase with dichloromethane (50 ml * 3). Combine the organic phases, dry with anhydrous magnesium sulfate, filter, rotary evaporate the filtrate to remove dichloromethane to obtain a crude product, and purify the crude product by silica gel column chromatography to obtain intermediate Q1. LC-MS: Measured value: 367.15 ([M+H]+ ); Exact mass: 366.09.

[0117] Intermediate M was prepared by a synthetic method similar to that of Intermediate M1, and the raw materials used are shown in Table 2;

[0118] Intermediate Q was prepared by a synthetic method similar to that of Intermediate Q1, and the raw materials used are shown in Table 2;

[0119] Table 2

[0120]

[0121]

[0122]

[0123] Mass spectrometry data of Intermediate M1: LC-MS: Measured value: 266.91 ([M+H] + ); Exact mass: 265.95.

[0124] Mass spectrometry data of Intermediate M2: LC-MS: Measured value: 266.98 ([M+H] + ); Exact mass: 265.95.

[0125] Mass spectrometry data of Intermediate M3: LC-MS: Measured value: 266.86 ([M+H] + ); Exact mass: 265.95.

[0126] Mass spectrometry data of Intermediate M4: LC-MS: Measured value: 266.94 ([M+H] + ); Exact mass: 265.95.

[0127] Mass spectrometry data of Intermediate M6: LC-MS: Measured value: 266.90 ([M+H] + ); Exact mass: 265.95

[0128] Example 1: Synthesis of Compound 1

[0129]

[0130] Under nitrogen protection, in a 500 ml round-bottom flask, Intermediate Q1 (7.34 g, 20 mmol), Intermediate P1 ((8.41 g, 22 mmol), K 2 CO 3 (8.29 g, 60 mmol), tetrahydrofuran (180 mL), water (60 mL) were successively added. Nitrogen was passed for 30 min to displace air, and Pd(PPh 3 ) 4(0.46 g, 0.4 mmol) was heated under reflux for 16 h under nitrogen protection. The reaction solution was taken for TLC detection and it was found that the intermediate Q1 had completely reacted. After the reaction was completed, the reaction system was naturally cooled to room temperature, and the solvent was removed by rotary evaporation. The residue was dissolved in 150 ml of dichloromethane, washed with 100 ml of water, poured into a separatory funnel, shaken, and allowed to stand for liquid separation. The aqueous phase was extracted with dichloromethane (50 ml × 3) after liquid separation. The combined organic phases were dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by rotary evaporation to remove dichloromethane to obtain the crude product. The crude product was purified by silica gel column chromatography to obtain Compound 1. Elemental analysis for C 42 H 26 N 4 , theoretical values: C, 85.98; H, 4.47; N, 9.55; measured values: C, 86.29; H, 4.36; N, 9.30. LC-MS: measured value: 587.51 ([M + H] + ), exact mass: 586.22.

[0131] Example 2: Synthesis of Compound 5

[0132]

[0133] Compound 5 was prepared according to the synthesis method of Compound 1 in Example 1, with the difference that intermediate P2 was selected to replace intermediate P1. Elemental analysis for C 42 H 26 N 4 , theoretical values: C, 85.98; H, 4.47; N, 9.55; measured values: C, 85.77; H, 4.59; N, 9.76. LC-MS: measured value: 587.18 ([M + H] + ), exact mass: 586.22.

[0134] Example 3: Synthesis of Compound 17

[0135]

[0136] Compound 17 was prepared according to the synthesis method of Compound 1 in Example 1, with the difference that intermediate Q2 was selected to replace intermediate Q1, and intermediate P3 was selected to replace intermediate P1. Elemental analysis for C 42 H 26 N 4 , theoretical values: C, 85.98; H, 4.47; N, 9.55; measured values: C, 86.19; H, 4.76; N, 9.47. LC-MS: measured value: 587.28 ([M + H] + ), exact mass: 586.22.

[0137] Example 4: Synthesis of Compound 28

[0138]

[0139] Compound 28 was prepared according to the synthesis method of Compound 1 in Example 1, except that intermediate Q3 was selected to replace intermediate Q1. Elemental analysis C 42 H 26 N 4 , theoretical values: C, 85.98; H, 4.47; N, 9.55; measured values: C, 86.07; H, 4.30; N, 9.72. LC-MS: measured value: 587.47 ([M+H] + ), exact mass: 586.22.

[0140] Example 5: Synthesis of Compound 31

[0141]

[0142] Compound 31 was prepared according to the synthesis method of Compound 1 in Example 1, except that intermediate Q3 was selected to replace intermediate Q1 and intermediate P2 was selected to replace intermediate P1. Elemental analysis C 42 H 26 N 4 , theoretical values: C, 85.98; H, 4.47; N, 9.55; measured values: C, 86.19; H, 4.48; N, 9.70. LC-MS: measured value: 587.24 ([M+H] + ), exact mass: 586.22.

[0143] Example 6: Synthesis of Compound 47

[0144]

[0145] Compound 47 was prepared according to the synthesis method of Compound 1 in Example 1, except that intermediate Q4 was selected to replace intermediate Q1 and intermediate P4 was selected to replace intermediate P1. Elemental analysis C 54 H 34 N 4 , theoretical values: C, 87.78; H, 4.64; N, 7.58; measured values: C, 88.00; H, 4.73; N, 7.37. LC-MS: measured value: 739.73 ([M+H] + ), exact mass: 738.28.

[0146] Example 7: Synthesis of Compound 61

[0147]

[0148] Compound 61 was prepared according to the synthesis method of compound 1 in Example 1, except that intermediate Q5 was selected to replace intermediate Q1, and intermediate P5 was selected to replace intermediate P1. Elemental analysis C 54 H 34 N 4 , theoretical values: C, 87.78; H, 4.64; N, 7.58; measured values: C, 88.09; H, 4.53; N, 7.76. LC-MS: measured value: 739.76 ([M+H] + ), exact mass: 738.28.

[0149] Example 8: Synthesis of Compound 84

[0150]

[0151] Compound 84 was prepared according to the synthesis method of compound 1 in Example 1, except that intermediate Q6 was selected to replace intermediate Q1, and intermediate P2 was selected to replace intermediate P1. Elemental analysis C 48 H 30 N 4 , theoretical values: C, 86.98; H, 4.56; N, 8.45; measured values: C, 86.87; H, 4.69; N, 8.55. LC-MS: measured value: 663.36 ([M+H] + ), exact mass: 662.25.

[0152] Example 9: Synthesis of Compound 100

[0153]

[0154] Compound 100 was prepared according to the synthesis method of compound 1 in Example 1, except that intermediate Q7 was selected to replace intermediate Q1. Elemental analysis C 42 H 26 N 4 , theoretical values: C, 85.98; H, 4.47; N, 9.55; measured values: C, 85.91; H, 4.47; N, 9.43. LC-MS: measured value: 587.27 ([M+H] + ), exact mass: 586.22.

[0155] Example 10: Synthesis of Compound 134

[0156]

[0157] Compound 134 was prepared according to the synthesis method of compound 1 in Example 1, except that intermediate Q8 was selected to replace intermediate Q1, and intermediate P2 was selected to replace intermediate P1. Elemental analysis C 42 H26 N 4 , Theoretical values: C, 85.98; H, 4.47; N, 9.55; Test values: C, 85.80; H, 4.33; N, 9.88. LC-MS: Measured value: 587.16 ([M+H] + ), Exact mass: 586.22.

[0158] Example 11: Synthesis of Compound 151

[0159]

[0160] Compound 151 was prepared according to the synthesis method of Compound 1 in Example 1, with the difference that intermediate Q9 was selected to replace intermediate Q1, and intermediate P4 was selected to replace intermediate P1. Elemental analysis of C 54 H 34 N 4 , Theoretical values: C, 87.78; H, 4.64; N, 7.58; Test values: C, 87.53; H, 4.67; N, 7.46. LC-MS: Measured value: 739.64 ([M+H] + ), Exact mass: 738.28.

[0161] Example 12: Synthesis of Compound 168

[0162]

[0163] Compound 168 was prepared according to the synthesis method of Compound 1 in Example 1, with the difference that intermediate Q10 was selected to replace intermediate Q1, and intermediate P5 was selected to replace intermediate P1. Elemental analysis of C 54 H 34 N 4 , Theoretical values: C, 87.78; H, 4.64; N, 7.58; Test values: C, 87.51; H, 4.68; N, 7.30. LC-MS: Measured value: 739.59 ([M+H] + ), Exact mass: 738.28.

[0164] Example 13: Synthesis of Compound 208

[0165]

[0166] Compound 208 was prepared according to the synthesis method of Compound 1 in Example 1, with the difference that intermediate Q11 was selected to replace intermediate Q1. Elemental analysis of C 42 H 26 N 4, Theoretical values: C, 85.98; H, 4.47; N, 9.55; Test values: C, 86.19; H, 4.41; N, 9.50. LC-MS: Measured value: 587.29 ([M+H] + ), Exact mass: 586.22.

[0167] Example 14: Synthesis of Compound 244

[0168]

[0169] Compound 244 was prepared according to the synthesis method of Compound 1 in Example 1, with the difference that intermediate Q12 was selected to replace intermediate Q1. Elemental analysis C 48 H 30 N 4 , Theoretical values: C, 86.98; H, 4.56; N, 8.45; Test values: C, 86.87; H, 4.71; N, 8.22. LC-MS: Measured value: 663.58 ([M+H] + )), Exact mass: 662.25.

[0170] Example 15: Synthesis of Compound 307

[0171]

[0172] Compound 307 was prepared according to the synthesis method of Compound 1 in Example 1, with the difference that intermediate Q5 was selected to replace intermediate Q1, and intermediate N5 was selected to replace intermediate P1. Elemental analysis C 48 H 30 N 4 , Theoretical values: C, 86.98; H, 4.56; N, 8.45; Test values: C, 86.70; H, 4.40; N, 8.56. LC-MS: Measured value: 663.61 ([M+H] + )), Exact mass: 662.25.

[0173] The compounds in the following Synthesis Examples 16-25 were prepared using the same method as in Synthesis Example 1, except that different raw materials and intermediates were used. The raw materials and intermediates used in the synthesis process are shown in Table 8 below.

[0174] Example 26: Synthesis of Compound 513

[0175]

[0176] Under nitrogen protection, Pd(dppf)Cl 2 (0.29 g, 0.4 mmol) was added to a degassed solution of raw material A6 (1.63 g, 4.2 mmol), intermediate N1 (3.25 g, 10.6 mmol) and KOAc (2.49 g, 25.4 mmol) in dry DMF (20 mL). The reaction mixture was stirred at 80 °C for 16 hours. After the reaction was completed, the reaction system was cooled to room temperature. After evaporating the solvent, the crude product was purified by column chromatography (SiO2, petroleum ether / AcOEt – 9:1) to obtain compound 513. Elemental analysis of C 42 H 26 N 4 , theoretical values: C, 85.98; H, 4.47; N, 9.55; measured values: C, 85.93; H, 4.40; N, 9.57. LC-MS: measured value: 587.16 ([M+H] + ), exact mass: 586.22.

[0177] The compounds in the following Synthesis Examples 27 - 32 were prepared using the same method as in Synthesis Example 26, except that different raw materials and intermediates were used. The raw materials and intermediates used in the synthesis process are shown in Table 9 below.

[0178] Table 8

[0179]

[0180]

[0181] Table 9

[0182]

[0183]

[0184] The organic compounds of the present invention can be used in light-emitting devices and can be used as electron transport layer materials.

[0185] The compounds of the present invention have good electron mobility and can be applied to electron transport materials. The glass transition temperature of the materials is greater than 135 °C, indicating that they have good film stability and durability. Moreover, the compounds of the present invention have a low evaporation temperature (<350 °C), which can effectively reduce the risk of thermal decomposition during evaporation of the materials. The compounds of the present invention have a high electron mobility, which is beneficial to the transport of electrons, thereby effectively reducing the operating voltage of the device and reducing the power consumption of the device.

[0186] Further, in order to show that when the compound of the present invention is used as a charge generation layer (CGL) material, it can form a stable and flat organic-metal doped film with metals such as Li and Yb, the surface roughness of the metal-organic doped film was tested, and the specific results are shown in Table 3.

[0187] Table 3

[0188]

[0189]

[0190] Note 2: The surface roughness was tested using an AFM device, and the device model was Bruker BioScope Resolve. The above materials were evaporated onto a flat quartz glass substrate, and the evaporation film thickness was 100 nm. The surface roughness was tested using an AFM device under an N 2 atmosphere. Among them, compound:Li = 97:3 means that the mass percentage of the compound and Li is 97:3.

[0191] As can be seen from the data in Table 3 above, the surface roughness of the doped film formed by the compound of the present invention and Li is significantly lower than that of the comparative compound. The lower surface roughness can effectively inhibit the phase separation of the organic material, improve the film contact stability of the organic layer material, and because the surface of the material has better stability, it can inhibit the local crystallization effect caused by Joule heat generated during the operation of the device, and improve the stability and life of the device operation.

[0192] The application effects of the compounds synthesized by the present invention as electron transport materials in single-layer OLED devices are described in detail below through Device Examples 1-15, 50-66 and Device Comparative Examples 1-10. Compared with Device Example 1, Device Examples 2-15, 50-66 and Device Comparative Examples 1-10 have exactly the same device manufacturing process, and the same substrate material and electrode material are used, and the film thickness of the electrode material also remains the same. The difference is that the electron transport material in the device has changed. The specific device structure is shown in Table 4.

[0193] Device Example 1

[0194] The specific preparation process is as follows:

[0195] As Figure 1As shown, the transparent substrate layer 1 is a transparent PI film. The ITO anode layer 2 is washed, that is, alkali washing, pure water washing, and drying are carried out in sequence, and then ultraviolet-ozone washing is carried out to remove organic residues on the surface of the anode layer. On the anode layer 2 after the above washing, using a vacuum evaporation device, HT-1 and P-1 with a film thickness of 10 nm are evaporated as the hole injection layer 3, and the mass ratio of HT-1 and P-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 5 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. Its structure includes that the OLED light-emitting layer 6 uses BH-1 as the host material and BD-1 as the doping material, and the doping ratio of the doping material is 3% by weight, and the film thickness of the light-emitting layer is 20 nm. After the above light-emitting layer 6, 5 nm of HB-1 is continuously vacuum-evaporated as the hole blocking layer 7; then, Compound 1 and Liq are evaporated, and the mass ratio of Compound 1 and Liq is 1:1, and the film thickness is 30 nm. This layer is the electron transport layer 8. On the electron transport layer 8, a Yb 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, an 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 the cathode layer 10.

[0196] After fabricating the electroluminescent device according to the above steps, the efficiency data and light decay lifetime of the device are measured, and the results are shown in Table 5. The molecular structural formulas of the related materials are as follows:

[0197]

[0198]

[0199] Table 4

[0200]

[0201]

[0202] The device is tested for its driving voltage, current efficiency, and LT95 lifetime. The driving voltage and current efficiency are tested using an IVL (current-voltage-brightness) test system (Suzhou Fosda Scientific Instruments Co., Ltd.), and the current density during the test is 10 mA / cm 2 . LT95 refers to the time when the device brightness decays to 95% of the initial brightness, and the current density during the test is 50 mA / cm 2 ; the lifetime test system is the EAS-62C type OLED device lifetime tester of System Technology Research Co., Ltd. of Japan. The efficiency and lifetime data of each device example and device comparative example are shown in Table 5.

[0203] Table 5

[0204]

[0205] As can be seen from the device data results in Table 5, the organic light-emitting device of the present invention has obtained a great improvement in both driving voltage and lifetime compared with the OLED device of the comparative material.

[0206] Furthermore, in order to illustrate the application of the compound of the present invention as a charge generation layer in an organic electroluminescent device, the material properties of the present invention are studied by constructing a stacked device (two-layer blue light device). It should be noted that since the optical design of the device needs to be considered for the stacked device, compared with the single-layer device structure, the film thickness and structure of the device need to be redesigned and adjusted, rather than simply stacking the single-layer devices.

[0207] The application effects of the synthesized compounds of the present invention as charge generation layer (CGL) materials in stacked OLED devices are described in detail below through Device Examples 16-35, 67-83 and Device Comparative Examples 11-20. Compared with Device Example 16, the manufacturing processes of the devices in Device Examples 17-35, 67-83 and Device Comparative Examples 11-20 are exactly the same, 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 CGL materials in the devices are changed. The specific device structures are shown in Table 6.

[0208] Device Example 16

[0209] The specific preparation process is as follows:

[0210] As Figure 1As shown, the transparent substrate layer 1 is a transparent PI film. The ITO anode layer 2 is washed, that is, alkali washing, pure water washing, and drying are carried out in sequence, and then ultraviolet-ozone washing is carried out to remove organic residues on the surface of the anode layer. On the anode layer 2 after the above washing, using a vacuum evaporation device, HT-1 and P-1 with a film thickness of 10 nm are evaporated as the hole injection layer 3, and the mass ratio of HT-1 and P-1 is 97:3. Then, HT-1 with a thickness of 40 nm is evaporated as the hole transport layer 4. Subsequently, EB-1 with a thickness of 10 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. Its structure includes that the OLED light-emitting layer 6 uses BH-1 as the host material and BD-1 as the doping material, and the doping ratio of the doping material is 3% by weight, and the film thickness of the light-emitting layer is 20 nm. After the above light-emitting layer 6, 6 nm of HB-1 is evaporated as the hole blocking layer 7; then, 20 nm of ETM-1 is continuously vacuum-evaporated as the electron transport layer 8. On the electron transport layer 8, through a vacuum evaporation device, the charge generation layer 9 (CGL layer) is evaporated, and its structure is Li: Compound 1 (the doping ratio of Li is 3% by weight) / HAT-CN, where the film thickness of Li: Compound 1 is 10 nm and the film thickness of HTA-CN is 5 nm. Then, HT-1 with a film thickness of 10 nm is evaporated as the hole transport layer 10. Subsequently, EB-1 with a thickness of 6 nm is evaporated as the electron blocking layer 11. After the evaporation of the above electron blocking material is completed, the light-emitting layer 12 of the OLED light-emitting device is fabricated. Its structure includes that the OLED light-emitting layer 12 uses BH-1 as the host material and BD-1 as the doping material, and the doping ratio of the doping material is 3% by weight, and the film thickness of the light-emitting layer is 20 nm. After the above light-emitting layer 13, 5 nm of HB-1 is continuously vacuum-evaporated, and this layer is the hole blocking layer 13. On the hole blocking layer 13, 20 nm of ETM-1 is evaporated as the electron transport layer 14. On the electron transport layer 14, through a vacuum evaporation device, the electron injection layer 15 with a film thickness of 10 nm is fabricated, and its structure is EI-1:Li (the doping ratio of Li is 3% by weight), and the film thickness is 10 nm. Finally, an 80-nm Mg:Ag electrode layer with a mass ratio of Mg to Ag of 1:9 is evaporated, and this layer is the cathode layer 16.

[0211] After fabricating the electroluminescent device according to the above steps, the efficiency data and light decay lifetime of the device are measured, and the results are shown in Table 7. The molecular structural formulas of the related materials are as follows:

[0212]

[0213]

[0214] Table 6

[0215]

[0216]

[0217] The device was tested for driving voltage, current efficiency and LT95 life. The driving voltage and current efficiency were tested using an IVL (current-voltage-luminance) test system (Suzhou Fushida Scientific Instrument Co., Ltd.) at a current density of 10 mA / cm 2 LT95 refers to the time it takes for the device brightness to decay to 95% of the initial brightness. The current density during the test is 50mA / cm 2 The life test system is an EAS-62C OLED device life tester produced by Japan System Technology Co., Ltd. The efficiency and life data of each device embodiment and device comparative example are shown in Table 7.

[0218] Table 7

[0219]

[0220]

[0221] From Table 5 and Table 7 above, it can be seen that the compounds of the present invention are used as electron transport materials in single-layer devices. Compared with the comparative materials, under the premise that the device current efficiency (cd / A) is basically the same, the device voltage is reduced and the device life is significantly improved, indicating that the compounds of the present invention have the technical effects of reducing voltage and increasing life. Further, in stacked devices, the compounds of the present invention are used as CGL materials. Compared with the comparative materials, the device voltage is reduced and the device life is improved, further indicating that the compounds of the present invention have the technical effects of low voltage and long life.

[0222] Thus, it can be seen that the compounds of the present application are connected to 1,10-phenanthroline derivatives by specific bridging groups (biphenyl or triphenyl), and due to the introduction of 1,10-phenanthroline, the group has a strong electron-withdrawing ability, can effectively improve electron injection and transmission ability, improve electron mobility, thereby reducing device driving voltage. Further, 1,10-phenanthroline directly, by adding specific bridging groups, effectively destroys the symmetry of the molecule, increases the three-dimensional structure of the molecule, suppresses the film crystallinity of the molecule, reduces the evaporation temperature of the molecule, improves the film stability and durability of the material, and is conducive to improving device efficiency and lifespan. And, because the compounds of the present invention have good electron-withdrawing ability, film stability and electronic tolerance, it is used as an n-type material of the CGL layer, and can form a stable N-metal coordination bond with metals such as Li or Yb, forming a stable and smooth organic-metal doped film, suppressing the oxidation of the metal, and is conducive to improving charge generation and device stability.

[0223] 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 compound containing a phenanthroline structure, characterized in that, the structure of the compound is shown as general formula (1): Ar 1 -L-Ar 2 General formula (1) In general formula (1), L represents a structure shown as general formula (C-1), general formula (C-2), general formula (C-3), general formula (C-4), general formula (C-5), general formula (C-6), general formula (C-7), general formula (C-8), general formula (C-9) or general formula (C-10); Ar 1 、Ar 2 are each independently represented by the structure shown in the general formula (2), and Ar 1 and Ar 2 are the same or different; In general formula (2), L 0 represents a single bond or a phenylene group; R 1 represents a hydrogen atom or a phenyl group.

2. The compound according to claim 1, characterized in that, the structure of the compound is shown as any one of general formulas (1-1) to (1-9): Ar 1 and Ar 2 have the same meaning as the definition in claim 1.

3. The compound according to claim 1, characterized in that, the structure of the compound is shown as any one of general formulas (2-1) to (2-9): Ar 1 and Ar 2 have the same meanings as the definitions in claim 1.

4. The compound according to claim 1, characterized in that, The general formula (2) is represented by any of the following structures:

5. The compound according to claim 1, characterized in that, the specific structure of the compound is any one of the following structures:

6. An OLED light-emitting device, comprising a first electrode, a second electrode and an organic functional layer, the organic functional layer is located between the first electrode and the second electrode, the organic functional layer includes a hole transport layer, a light-emitting layer and an electron transport layer, and the light-emitting layer is located between the hole transport layer and the electron transport layer, characterized in that, the electron transport layer contains the compound containing a phenanthroline structure according to any one of claims 1-5.

7. An OLED stacked light-emitting device, comprising a first electrode, a second electrode, a first light-emitting unit, a second light-emitting unit and a charge generation layer, the first light-emitting unit, the second light-emitting unit and the charge generation layer are located between the first electrode and the second electrode, and the charge generation layer is located between the first light-emitting unit and the second light-emitting unit, characterized in that, the charge generation layer contains the compound containing a phenanthroline structure according to any one of claims 1-5.

8. The OLED stacked light-emitting device according to claim 7, characterized in that, the first light-emitting unit includes a hole transport region, a light-emitting layer and an electron transport region, and the second light-emitting unit includes a hole transport region, a light-emitting layer and an electron transport region.

9. The OLED stacked light-emitting device according to claim 7, characterized in that, the charge generation layer further contains a metal material.

10. The OLED stacked light-emitting device according to claim 9, characterized in that, the metal material is Li, Ca, Ag, Cs or Yb.

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