Compound containing triazine and naphthyl as well as organic electroluminescent device and display element thereof

Abstract

The invention discloses a compound containing triazine and naphthyl, and an organic electroluminescent device and a display element thereof, and belongs to the technical field of semiconductor materials. The structure of the compound containing the triazine and the naphthyl is shown as any one of the general formula (1): # imgabs0 #, an organic electroluminescent device comprises a substrate, a first electrode and a second electrode, a plurality of organic thin film layers are arranged between the first electrode and the second electrode, and the organic thin film layers contain the compound containing the triazine and the naphthyl. The invention further discloses a display element. The display element comprises the organic light-emitting device provided by the invention. The triazine and naphthyl-containing compound has good stability and electron endurance capability, and also has good electron injection and electron transport capabilities, and when the triazine and naphthyl-containing compound is used as a material of an organic electroluminescent device, the driving voltage of the device is significantly reduced, and the service life of the device is significantly improved.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor materials, in particular to a compound containing triazine and naphthyl, and an organic electroluminescent device and a display element thereof. Background Art

[0002] Organic light emitting diode (OLED) technology can be used to manufacture new display products as well as new lighting products. It is expected to replace existing liquid crystal displays and fluorescent lighting, and has a wide range of applications. Organic light emitting diodes have a sandwich-like structure, including electrode material films and organic functional materials sandwiched between different electrode material films. Various organic functional materials are superimposed on each other according to their uses to form organic light emitting diodes. As a current device, when voltage is applied to the electrodes at both ends of the organic light emitting diode and the electric field acts on the positive and negative charges in the organic layer functional material film layer, the positive and negative charges further recombine in the light emitting layer, generating organic electroluminescence.

[0003] Currently, OLED display technology has been applied in smart phones, tablet computers, TVs and other fields. However, compared with the actual product application requirements, the performance of organic electroluminescent devices such as luminous efficiency and service life needs to be further improved. In order to continuously improve the performance of organic electroluminescent devices, it is necessary to continuously research and innovate organic optoelectronic functional materials to create higher performance organic optoelectronic functional materials.

[0004] Organic optoelectronic functional materials used in organic electroluminescent devices can be divided into two categories based on their uses, namely charge injection transport materials and luminescent materials. Furthermore, charge injection transport materials can also be divided into electron injection transport materials, electron blocking materials, hole injection transport materials and hole blocking materials. As charge transport materials, they are required to have good carrier mobility, high glass transition temperature, etc. For organic electroluminescent devices, electrons are injected from the cathode and then transferred to the main material through the electron transport layer, where they recombine with holes to generate excitons. Therefore, improving the injection and transmission capabilities of the electron transport layer is conducive to reducing the device driving voltage while obtaining efficient electron-hole recombination efficiency. Therefore, the electron transport layer is very important and requires it to have efficient electron injection capability, transmission capability and high electronic durability.

[0005] For the device life, 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 caused by the heat generated by the device when the device is working, resulting in material degradation. In the case of poor phase stability of the material film, the material will also undergo thin film crystallization in a short period of time, resulting in direct layer separation of the organic film layer and device degradation. Therefore, the materials used are required to have high heat resistance and good film stability.

[0006] With the demand for improving the performance of organic electroluminescent devices, the requirements for material performance are also increasing. Not only are they required to have good material stability, but they are also required to achieve good efficiency and life at low driving voltages. However, the current electron transport materials have insufficient thermal stability and defects in the electronic tolerance of the materials, which leads to phase separation or decomposition of the materials when the device is working, resulting in a short device life. Summary of the invention

[0007] In view of the above problems existing in the prior art, the applicant of the present invention provides a compound containing triazine and naphthyl, and an organic electroluminescent device and a display element thereof. The compound of the present invention is bridged by a naphthyl group of a specific structure, so that the compound has excellent electron injection and transmission capabilities. When applied to an organic electroluminescent device, it can effectively reduce the operating voltage of the device and extend the working life of the device.

[0008] A compound containing triazine and naphthyl, wherein the structure of the compound containing triazine and naphthyl is shown in general formula (1):

[0009]

[0010] In the general formula (1), * represents the attachment site;

[0011] L1 and L2 are independently selected from a single bond, a phenylene group substituted or unsubstituted by a cyano group, and at least one of L1 and L2 is a single bond;

[0012] A and B are independently selected from the general formula (2) or the general formula (3), and at least one of A and B is represented by the general formula (2). When one and only one of L1 or L2 is represented by a phenyl group substituted or unsubstituted by a cyano group, A and B may be the same or different; when L1 or L2 are both represented by a single bond, A and B must be different;

[0013]

[0014] In the general formula (2) and the general formula (3),

[0015] Ar1、A r2, Ar3, Ar4 each independently represent substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted pyridyl, substituted or unsubstituted pyrimidinyl;

[0016] Ar1、A r2 , Ar3, Ar4 may be the same or different;

[0017] X1, X2, and X3 are each independently represented by CH or N; and at least two of X1, X2, and X3 are represented by N;

[0018] The substituent of the substitutable group may be selected from cyano, phenyl, biphenyl, terphenyl, pyridyl, pyrimidyl;

[0019] The general formula (1) does not include the following structures:

[0020]

[0021] Furthermore, the structure of the compound containing triazine and naphthyl is shown in any one of general formulas (2-1) to (2-4):

[0022]

[0023] In the general formula (2-1) to the general formula (2-4), Ar1, A r2 , Ar3, Ar4, X1, X2, and X3 have the same meanings as above; * represents a connection site.

[0024] Furthermore, the structure of the compound containing triazine and naphthyl is shown in any one of general formulas (3-1) to (3-8):

[0025]

[0026] In the general formula (3-1) to the general formula (3-8), Ar 1 , A r 2 ,Ar 3 ,Ar 4 , X 1 , X 2 , X 3 The meaning is the same as above.

[0027] Furthermore, the triazine and naphthyl-containing compound is characterized in that when one and only one of L1 or L2 is represented by a phenyl group substituted or unsubstituted by a cyano group, A and B are simultaneously represented by the general formula (2).

[0028] Furthermore, the triazine and naphthyl-containing compound is characterized in that, when one and only one of L1 or L2 is represented by a phenyl group substituted or unsubstituted by a cyano group, A and B are each independently represented by the general formula (2) or the general formula (3), and two of X1, X2, and X3 are represented by N.

[0029] Furthermore, the structure of the compound containing triazine and naphthyl is shown in any one of general formulas (4-1) to (4-14):

[0030]

[0031] In the general formula (4-1) to the general formula (4-14), Ar1, A r2 , Ar3, Ar4, X1, X2, and X3 have the same meanings as above.

[0032] Further, L1 and L2 are independently selected from a single bond, an o-phenylene group substituted or unsubstituted by a cyano group, an m-phenylene group substituted or unsubstituted by a cyano group, and a p-phenylene group substituted or unsubstituted by a cyano group;

[0033] Ar1, A r2 , Ar3, Ar4 are each independently represented by the following structure:

[0034]

[0035]

[0036] Any one of.

[0037] Furthermore, the specific structure of the compound containing triazine and naphthyl is any one of the following structures:

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050] The invention also discloses an organic electroluminescent device, comprising a substrate, a first electrode and a second electrode, wherein a plurality of organic thin film layers are provided between the first electrode and the second electrode, and the organic thin film layers contain the triazine- and naphthyl-containing compounds of the invention.

[0051] Furthermore, the organic thin film layer includes a hole transport region thin film layer, a light emitting region thin film layer and an electron transport region thin film layer, and the electron transport region thin film layer contains the triazine and naphthyl-containing compound of the present invention.

[0052] Furthermore, the electron transport region thin film layer comprises an electron transport layer, and the electron transport layer contains the triazine- and naphthyl-containing compound of the present invention.

[0053] Furthermore, the hole transport region thin film layer comprises a hole injection layer, a hole transport layer and an electron blocking layer, the electron transport region thin film layer comprises a hole blocking layer, an electron transport layer and an electron injection layer, and the electron transport layer contains the triazine and naphthyl-containing compound of the present invention.

[0054] The invention also discloses a display element, which contains the organic electroluminescent device of the invention.

[0055] Technical Effects

[0056] The compounds of the present invention are based on nitrogen-containing heterocyclic rings and naphthyl structures, triazine and pyrimidine groups or triazine and triazine groups are connected by specific naphthyl bridging groups, and the triazine and naphthyl framework bridging characteristics are formed. Such compounds have good electronic tolerance and stability, and have good electron injection and transmission capabilities. Therefore, when used as an electron transmission material for an OLED functional layer, it can effectively reduce the device driving voltage and improve the optoelectronic performance and device life of the OLED device.

[0057] Since triazine can further delocalize the LUMO electron cloud distribution of the material, it can improve the anti-electronic properties of the material and effectively improve the electronic stability of the material. In addition, the parent core can increase the weak interaction within the molecule, effectively reduce the evaporation temperature of the molecule, and improve the thermal durability of the material. Furthermore, since the parent core can inhibit the π-π stacking between molecules, it significantly improves the electron mobility of the molecule and reduces the driving voltage of the device. In addition, due to the existence of the electron-withdrawing conjugation effect of the parent core, the glass transition temperature of the material is increased, and the film stability of the material is effectively improved. Therefore, it is possible to effectively reduce the device driving voltage, improve the device efficiency and service life.

[0058] In addition, under the action of electric field or thermal energy, the triazine and naphthyl-containing compound of the present invention can easily reduce and free lithium ions in the lithium complex due to its strong electron-withdrawing conjugation effect, thereby improving the electron injection capacity. Therefore, the triazine and naphthyl-containing compound as an electron transport material has excellent electron transport capacity and good electron injection properties, which can effectively reduce the device driving voltage, improve the device efficiency and service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 Schematic diagram of the structure of OLED devices in device embodiments and device comparative examples;

[0060] In the figure, 1 is a transparent substrate layer, 2 is an anode layer, 3 is a hole injection layer, 4 is a hole transport layer, 5 is an electron blocking layer, 6 is a light emitting layer, 7 is a hole blocking layer, 8 is an electron transport layer, 9 is an electron injection layer, 10 is a cathode layer, and 11 is a light extraction layer.

[0061] Figure 2 This is the H NMR spectrum of compound 168 in deuterated reagent CDCl3. DETAILED DESCRIPTION

[0062] The technical solution of the present invention will be described in detail below in conjunction with the implementation scheme.

[0063] In the present invention, unless otherwise specified, HOMO means the highest occupied orbital of a molecule, and LUMO means the lowest unoccupied orbital of a molecule. In addition, in the present invention, HOMO and LUMO energy levels are expressed in absolute values, and the comparison between energy levels is also a comparison of the magnitude of their absolute values. Those skilled in the art know that the greater the absolute value of an energy level, the lower the energy of the energy level.

[0064] In the drawings, the sizes of layers and regions may be exaggerated for clarity. 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 intervening layers may also be present. In addition, it will 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 intervening layers may also be present.

[0065] In the present invention, when describing electrodes and organic electroluminescent devices, as well as other structures, the words "upper" and "lower" used to indicate orientation only indicate orientation in a certain state, and do not mean that the related structure can only exist in the orientation described; on the contrary, if the structure can change its position, such as inverted, the orientation of the structure will be changed accordingly. Specifically, in the present invention, the "lower" side of the electrode refers to the side of the electrode close to the substrate during the preparation process, and the opposite side away from the substrate is the "upper" side.

[0066] Organic electroluminescent devices

[0067] The organic electroluminescent device of the present invention may be a bottom-emitting organic electroluminescent device, a top-emitting organic electroluminescent device, or a stacked organic electroluminescent device, without any particular limitation.

[0068] The organic electroluminescent device of the present invention comprises a substrate, a first electrode, a multi-layer organic thin film layer and a second electrode. The multi-layer organic thin film layer comprises a hole transport region, a light-emitting layer and an electron transport region, the hole transport region comprises a hole injection layer, a hole transport layer and an electron blocking layer, the electron transport region comprises a hole blocking layer, an electron transport layer and an electron injection layer, and a covering layer may be provided on the second electrode.

[0069] The organic electroluminescent device of the present invention may include layers and the positional relationship of each layer is as follows: it may include a substrate, a first electrode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer and a second electrode. If the above layers exist, the first electrode is above the substrate, the hole injection layer is above the first electrode, the hole transport layer is above the hole injection layer, the electron blocking layer is above the hole transport layer, the light-emitting layer is above the electron blocking layer, the hole blocking layer is above the light-emitting layer, the electron transport layer is above the hole blocking layer, the electron injection layer is above the electron transport layer, the second electrode is above the electron injection layer, and the covering layer is above the second electrode.

[0070] 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 stability, transparency, surface smoothness, and waterproofness. Depending on the properties of the substrate, its use direction is different. In the present invention, it is preferred to use a transparent substrate, and the thickness of the substrate is not particularly limited.

[0071] A first electrode is formed on a substrate, and the first electrode and the second electrode may be opposite to each other. The first electrode may be an anode or a cathode. In the present invention, the first electrode is used as an anode, and the anode material is preferably a material with a high work function so that holes are easily injected into the organic functional material layer. Non-limiting examples of anode materials include, but are not limited to, indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), zinc oxide (ZnO), magnesium (Mg), aluminum (Al), silver (Ag), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In) and magnesium-silver (Mg-Ag). The first electrode may have a single-layer structure or a multilayer structure including two or more layers. In addition, the thickness of the anode depends on the material used, typically 50-500nm, preferably 70-300nm, and more preferably 100-200nm.

[0072] A hole injection layer, a hole transport layer, and an electron blocking layer may be disposed between the first electrode and the light emitting layer.

[0073] The hole injection layer may include a main material and a P-type doping material, wherein the main material may be selected from conventional hole transport materials in the prior art, preferably the same organic material as the hole transport layer, and the P-type doping material is selected from compounds with charge conductivity disclosed in the prior art, and may be selected from compounds disclosed in the following patent documents: WO2011073149A, EP1968131A1, EP2276085A1, EP2213662A1, EP1722602A1, EP2 045848A1, DE102007031220A1, US20100181555A1, US20100102709A1, WO2009003455A1, WO2010094378A1, WO2011120709A1, US20100096600A1, DE102012209523A1, CN101728485A and WO2012095143A1, but are not limited thereto.

[0074] For example, the compound shown below:

[0075]

[0076] According to the present invention, P1 is preferably used as the P-type doping material.

[0077] The thickness of the hole injection layer of the present invention may be 1-100 nm, preferably 2-50 nm, and more preferably 5-20 nm.

[0078] The material of the hole transport layer is preferably a material having high hole mobility, which enables holes to be transferred from the anode or the hole injection layer to the light emitting layer.

[0079] Preferably, the hole transport layer material of the present invention may be selected from the following compounds disclosed in the prior art:

[0080]

[0081] The thickness of the hole transport layer of the present invention may be 5-200 nm, preferably 10-180 nm, and more preferably 20-150 nm.

[0082] The electron blocking layer requires that the triplet state (T1) energy level of the material is higher than the T1 energy level of the main material in the light-emitting layer, which can play a role in blocking the energy loss of the light-emitting layer material; the HOMO energy level of the electron blocking layer material is between the HOMO energy level of the hole transport layer material and the HOMO energy level of the main material of the light-emitting layer, which is conducive to the injection of holes from the positive electrode into the light-emitting layer. At the same time, the electron blocking layer material is required to have a high hole mobility, which is conducive to hole transport and reduces the power of the device; the LUMO energy level of the electron blocking layer material is higher than the LUMO energy level of the main material of the light-emitting layer, which plays a role in electron blocking, that is, the electron blocking layer material is required to have a wide bandgap width (Eg). The electron blocking layer materials that meet the above conditions can be triarylamine derivatives, fluorene derivatives, spirofluorene derivatives, dibenzofuran derivatives, carbazole derivatives, etc.

[0083] In one embodiment of the present invention, the electron blocking layer material of the present invention may be selected from the following compounds disclosed in the prior art:

[0084]

[0085] According to the present invention, the thickness of the electron blocking layer may be 1-200 nm, preferably 5-150 nm, and more preferably 5-50 nm.

[0086] According to the present invention, the light-emitting layer is located between the electron blocking layer and the hole blocking layer, and the material of the light-emitting layer is a material that can emit visible light by receiving holes from the hole transport region and electrons from the electron transport region respectively, and combining the received holes and electrons. The light-emitting layer may include a host material and a doping material. As the host material and guest material of the light-emitting layer of the organic electroluminescent device of the present invention, the host material may be one or a combination of two of anthracene derivatives, quinoxaline derivatives, triazine derivatives, xanthone derivatives, diphenyl ketone derivatives, carbazole derivatives, pyridine derivatives or pyrimidine derivatives. The guest material may be a pyrene derivative, a boron derivative, a chrysene derivative, a spirofluorene derivative, an iridium complex or a platinum complex.

[0087] The thickness of the light-emitting layer of the present invention may be 5-60 nm, preferably 10-50 nm, and more preferably 20-45 nm.

[0088] The hole blocking layer can be arranged on the light-emitting layer. The triplet state (T1) energy level of the hole blocking layer material is higher than the T1 energy level of the main material of the light-emitting layer, which can play a role in blocking the energy loss of the light-emitting layer material; the HOMO energy level of the material is lower than the HOMO energy level of the main material of the light-emitting layer, which plays a role in hole blocking. At the same time, the hole blocking layer material is required to have a high electron mobility, which is conducive to electron transmission and reduces the application power of the device; the hole blocking layer material that meets the above conditions can be triazine derivatives, azabenzene derivatives, etc. Among them, triazine derivatives are preferred; but not limited to this.

[0089] As the hole blocking layer of the organic electroluminescent device of the present invention, the hole blocking layer material for organic electroluminescent devices disclosed in the following prior art can be used:

[0090]

[0091] The thickness of the hole blocking layer of the present invention may be 2-200 nm, preferably 5-150 nm, and more preferably 5-50 nm, but the thickness is not limited to this range.

[0092] The electron transport layer may be disposed above 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. The electron transport layer comprises one or more organic compounds of the present invention. Preferably, the electron transport layer consists of the organic compound of the present invention and other electron transport layer materials. More preferably, the other electron transport layer materials are electron transport materials commonly used in the art. Most preferably, the electron transport layer consists of the organic compound of the present invention and LiQ, and the ratio of the organic compound of the present invention to the other electron transport layer materials is 1:9-9:1, preferably 2:8-8:2, more preferably 4:6-6:4, and most preferably 5:5.

[0093] 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.

[0094] According to the present invention, the electron injection layer can be arranged between the electron transport layer and the cathode. The electron injection layer material is generally preferably a material with a low work function, so that electrons are easily injected into the organic functional material layer. Preferably, the electron injection layer material is an N-type metal material. As the electron injection layer material of the organic electroluminescent device of the present invention, the electron injection layer materials for organic electroluminescent devices disclosed in the following prior art can be used: LiF, Cs2CO3, CsF, Csq, NaF, MgF2, CaF2, Al2O3, Yb.

[0095] The thickness of the electron injection layer of the present invention may be 0.1-5 nm, preferably 0.5-3 nm, more preferably 0.8-1.5 nm, but the thickness is not limited to this range.

[0096] According to the present invention, as mentioned above, the second electrode can be a cathode or an anode. In the present invention, the second electrode is used as a cathode. The material used to form the cathode can be a material with a low work function, such as a metal, an alloy, a conductive compound or a mixture thereof. Non-limiting examples of cathode materials can include lithium (Li), ytterbium (Yb), magnesium (Mg), aluminum (Al), calcium (Ca), and aluminum-lithium (Al-Li), magnesium-indium (Mg-In) and magnesium-silver (Mg-Ag). The thickness of the cathode depends on the material used, typically 5-100nm, preferably 7-50nm, and more preferably 10-25nm.

[0097] Optionally, in order to improve the light extraction efficiency of the organic electroluminescent device, a light extraction layer (ie, CPL layer) may be added on the second electrode (ie, cathode) of the device. The following compounds disclosed in the prior art may be used as CPL layer materials.

[0098]

[0099] The thickness of the CPL layer is generally 5-300 nm, preferably 20-100 nm, and more preferably 40-80 nm.

[0100] The organic electroluminescent device may further include an encapsulation structure. The encapsulation structure may be a protective structure that prevents foreign substances such as moisture and oxygen from entering the organic layer of the organic electroluminescent device. The encapsulation 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.

[0101] Organic electroluminescent device preparation method

[0102] The method for preparing the above-mentioned organic electroluminescent device of the present invention comprises laminating a first electrode, a multi-layer organic thin film layer and a second electrode on a substrate in sequence. The multi-layer organic thin film layer is formed by laminating a hole transport region, a light-emitting layer and an electron transport region on the first electrode from bottom to top, the hole transport region is formed by laminating a hole injection layer, a hole transport layer and an electron blocking layer on the first electrode in sequence from bottom to top, and the electron transport region is formed by laminating a hole blocking layer, an electron transport layer and an electron injection layer on the light-emitting layer in sequence from bottom to top. In addition, optionally, a CPL layer can also be laminated on the second electrode to improve the light extraction efficiency of the organic electroluminescent device.

[0103] For lamination, vacuum deposition, vacuum evaporation, spin coating, casting, LB method, inkjet printing, laser printing or LITI methods may be used, but are not limited thereto. Vacuum evaporation means heating and coating a material onto a substrate in a vacuum environment.

[0104] In the present invention, the various layers are preferably formed by vacuum evaporation, wherein the layers can be formed at a temperature of about 100-500° C. and at a temperature of about 10 -8 -10 -2 Torr vacuum and approx. The vacuum evaporation is carried out at a rate of 10 -6 -10 -2 Torr, preferably 10 -5 -10 -3 Torr. The rate is about More preferably, about

[0105] In addition, it should be noted that the materials used to form each layer described in the present invention can be formed into a film alone and used as a single layer, or can be mixed with other materials to form a film and used as a single layer. It can also be a stacked structure between layers formed into films alone, a stacked structure between layers formed into films after mixing, or a stacked structure of layers formed into films alone and layers formed into films after mixing.

[0106] Display components

[0107] The present invention also relates to a display element comprising the above-mentioned organic electroluminescent device, in particular a flat panel display element. In a preferred embodiment, the display element may include one or more of the above-mentioned organic electroluminescent devices, and in the case of including a plurality of devices, the devices are stacked and combined laterally or longitudinally. The display element may also include at least one thin film transistor. The thin film transistor may include a gate electrode, a source electrode and a drain electrode, a gate insulating layer and an active layer, wherein one of the source electrode and the drain electrode may be electrically connected to the first electrode of the organic electroluminescent device. The active layer may include crystalline silicon, amorphous silicon, an organic semiconductor or an oxide semiconductor, but is not limited thereto.

[0108] Exemplary embodiments have been disclosed herein, and although specific terms are used therein, these terms are used and interpreted only as general and descriptive meanings, and not for limiting purposes. In some cases, as will be apparent to those of ordinary skill in the art with the filing of this application, unless specifically indicated, the features, characteristics, and / or elements described in conjunction with a particular embodiment may be used alone or in combination with the features, characteristics, and / or elements described in conjunction with other embodiments. Accordingly, it will be understood by those skilled in the art that various changes may be made in form and detail without departing from the spirit and scope of the invention.

[0109] The following examples are intended to better explain the present invention, but the scope of the present invention is not limited thereto.

[0110] Example

[0111] I. Compound Preparation Examples

[0112] The raw materials involved in the synthesis examples of the present invention can be purchased from the market or prepared by conventional preparation methods in the art;

[0113] Preparation of intermediate C1:

[0114]

[0115] Under nitrogen atmosphere, in a 500 ml round-bottom flask, raw material B1 (12.7 g, 50 mmol), potassium acetate (9.3 g, 95 mmol) and [1,1'-bis(diphenylphosphino)ferrocene] dichloropalladium (II) dichloromethane complex (0.8 g, 0.95 mmol) were added to 80 mL of 1,4-dioxane dissolved raw material A1 (16.6 g, 50 mmol) solution. The reaction mixture was heated at 100 ° C for 17 hours. The reaction mixture was diluted with dichloromethane. The reaction mixture was washed with 2*100 mL of water. The organic phase was dried over anhydrous MgSO4. The organic phase was concentrated under reduced pressure. The remaining product was purified by column chromatography to obtain intermediate C1. LC-MS: Measured value: 333.28 ([M+H] + ), exact mass: 332.06.

[0116]

[0117] Intermediate C2 was prepared according to the synthetic method of intermediate C1, except that raw material A2 was used to replace raw material A1. LC-MS: Measured value: 333.14 ([M+H] + ), exact mass: 332.06.

[0118] Preparation of intermediates E1 and F1:

[0119]

[0120] Under nitrogen protection, in a 250 ml round-bottom flask, intermediate C1 (3.3 g, 10 mmol), raw material D1 (3.2 g, 12 mmol), KOAc (2.9 g, 30 mmol), tetrahydrofuran (100 mL), water (30 mL) were added in sequence, nitrogen was passed through for 30 min to replace the air, Pd(dppf)Cl2 (0.06 g, 0.08 mmol) and 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (0.06 g, 0.13 mmol) were added, and the mixture was heated to 60 ° C and refluxed for 15 h under nitrogen protection. The reaction solution was taken for TCL detection to find that the raw material C1 was completely reacted. After the reaction was completed, the reaction system was naturally cooled to room temperature, the solvent was removed by rotary evaporation, 80 ml of dichloromethane was added to the residue to dissolve, 100 ml of water was added to wash, poured into a separatory funnel and shaken, and then allowed to stand for stratification. After separation, the aqueous phase was extracted with dichloromethane (30 ml*3), the organic phases were combined and dried with anhydrous magnesium sulfate, filtered, and the filtrate was subjected to rotary evaporation to remove dichloromethane to obtain a crude product, which was purified by silica gel chromatography to obtain intermediate E1. LC-MS: Measured value: 437.28 ([M+H] + ), exact mass: 436.06.

[0121] The other intermediates E were prepared by the same synthetic method as intermediate E1, except that the raw materials were different. The raw materials and intermediates used are shown in Table 1;

[0122] Table 1

[0123]

[0124]

[0125] The same synthesis method as intermediate C1 was used to prepare other intermediates F, except that the raw materials were different. The raw materials and intermediates used are shown in Table 2;

[0126] Table 2

[0127]

[0128]

[0129]

[0130] Example 1: Synthesis of Compound 1

[0131]

[0132] Under nitrogen atmosphere, in a 500ml round-bottom flask, the intermediate F1 (4.84g, 10mmol) and the raw material D4 (3.21g, 12mmol) were completely dissolved in 150ml of a mixed solution of toluene, water and ethanol in a volume ratio of 3:1:1, and then 100ml of 2M potassium carbonate solution (K2CO3) was added. After adding Pd(PPh3)4 (0.35g, 0.30mmol), the mixture was heated and stirred at 105°C for 6 hours, then cooled to room temperature, the water layer was removed, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure, and recrystallized from 280ml of ethyl acetate to obtain compound 1. Elemental analysis: C 41 H 27 N5 theoretical value: C, 83.51; H, 4.62; N, 11.88; test value: C, 83.48; H, 4.63; N, 11.90. LC-MS: Found: 590.05 ([M+H] + ), exact mass: 589.23.

[0133] The same synthesis method as compound 1 was used to prepare other compounds, except that the intermediates and raw materials were different. The raw materials and intermediates used are shown in Table 3;

[0134] Table 3

[0135]

[0136]

[0137]

[0138]

[0139] II. Device Preparation Example

[0140] The following describes in detail the application effect of the compound synthesized according to the present invention as an electron transport material in the device through device examples 1-22 and device comparative examples 1-14. Compared with device comparative examples 1-14, device examples 1-22 have the same manufacturing process of the device, and use the same substrate material and electrode material, and the film thickness of the electrode material is also consistent. The difference is that the electron transport layer material in the device has changed. The device layer structure is shown in Table 4, and the performance test results of each device are shown in Table 5.

[0141] The molecular structure formula of the relevant materials is shown below:

[0142]

[0143]

[0144] The structures of comparative compounds ET-1, ET-2, ET-3, ET-4, ET-5, ET-6, ET-7, ET-8, ET-9, ET-10, ET-11, ET-12, ET-13 and ET-14 are shown above. All the above materials were purchased commercially.

[0145] Device Comparison Example 1

[0146] The specific preparation process is as follows:

[0147] like Figure 1 As shown, the transparent substrate layer 1 is transparent glass, and Ag (100nm) is evaporated as the anode layer 2. On the anode layer 2, a vacuum evaporation device is used to evaporate HT-1 and P-1 with a film thickness of 10nm 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 130nm is evaporated as the hole transport layer 4. Then, EB-1 with a thickness of 5nm is evaporated as the electron blocking layer 5. After the above-mentioned electron blocking material is evaporated, the light-emitting layer 6 of the OLED light-emitting device is prepared, using BH-1 as the main material and BD-1 as the doping material. The doping ratio of the doping material is 3% by weight, and the film thickness of the light-emitting layer 6 is 20nm. After the above-mentioned light-emitting layer 6, HB-1 is continuously evaporated, and the film thickness is 5nm, as a hole blocking layer 7. On the above-mentioned hole blocking layer 7, ET-1 and LiQ are continuously evaporated, and the mass ratio of ET-1 and LiQ is 1:1. The vacuum-deposited film thickness of the material is 30 nm, and this layer is the electron transport layer 8. On the electron transport layer 8, a LiF layer with a film thickness of 1 nm is made by a vacuum evaporation device, and this layer is the electron injection layer 9. On the electron injection layer 9, a Mg:Ag electrode layer with a film thickness of 16 nm is made by a vacuum evaporation device, and the mass ratio of Mg to Ag is 1:9, and this layer is used as the cathode layer 10. On the cathode layer 10, 65 nm of CP-1 is vacuum-deposited as the light extraction layer 11.

[0148] Device Examples 1-22 and Device Comparative Examples 2-14 were prepared in a similar manner to Device Comparative Example 1, except that the electron transport layer materials in Table 4 below were used.

[0149] Table 4

[0150]

[0151]

[0152]

[0153]

[0154] III. Device Testing Example

[0155] The device prepared in II was tested for its driving voltage and LT95 life. The voltage was tested using an IVL (current-voltage-luminance) test system (Suzhou Fushida Scientific Instrument Co., Ltd.) with 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 30mA / cm 2 The life test system is the EAS-62C OLED device life tester from Japan System Technology Co., Ltd. The high temperature life test temperature is 85°C, LT95 refers to the time taken for the device brightness to decay to 95% of the initial brightness, and the current density during the test is 20mA / cm 2 ; The test results are shown in Table 5 below.

[0156] Table 5

[0157]

[0158]

[0159] It can be seen from the device test data results in Table 5 above that compared with the comparative devices using ET-1, ET-2, ET-3, ET-4, ET-5, ET-6, ET-7, ET-8, ET-9, ET-10, ET-11, ET-12, ET-13, and ET-14 as electron transport layer materials, the device driving voltage prepared using the compounds of the present invention as electron transport layer materials is significantly reduced, while at the same time extending the device life. For example, its life is substantially more than 1.25 times that of comparative devices 1-5.

[0160] The structural formulas of the comparative compounds ET-1, ET-2, ET-3, ET-4, ET-5, ET-6, ET-7, ET-8, ET-9, ET-10, ET-11, ET-12, ET-13, and ET-14 used in the comparative examples are close to those of the present invention. However, the compounds of the present invention have achieved better technical effects as electron transport materials than the comparative compounds.

[0161] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A compound containing triazine and naphthyl, characterized in that: The structure of the compound containing triazine and naphthyl is shown in general formula (1): In the general formula (1), * represents the attachment site; L1 and L2 are independently selected from a single bond, a phenylene group substituted or unsubstituted by a cyano group, and at least one of L1 and L2 is a single bond; A and B are independently selected from the general formula (2) or the general formula (3), and at least one of A and B is represented by the general formula (2). When one and only one of L1 or L2 is represented by a phenyl group substituted or unsubstituted by a cyano group, A and B may be the same or different; when L1 or L2 are both represented by a single bond, A and B must be different; In the general formula (2) and the general formula (3), Ar1、A r2 , Ar3, Ar4 each independently represent substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted pyridyl, substituted or unsubstituted pyrimidinyl; Ar1、A r2 , Ar3, Ar4 may be the same or different; X1, X2, and X3 are each independently represented by CH or N; and at least two of X1, X2, and X3 are represented by N; The substituent of the substitutable group may be selected from cyano, phenyl, biphenyl, terphenyl, pyridyl, pyrimidyl; The general formula (1) does not include the following structures:

2. A compound containing triazine and naphthyl structure according to claim 1, characterized in that: The structure of the compound containing triazine and naphthyl is shown in any one of the general formulas (2-1) to (2-4): In the general formula (2-1) to the general formula (2-4), Ar1, A r2 , Ar3, Ar4, X1, X2, X3 have the same meanings as defined in claim 1; * represents the connection site.

3. A compound containing triazine and naphthyl according to claim 1, characterized in that: The structure of the compound containing triazine and naphthyl is shown in any one of the general formulas (3-1) to (3-8): In the general formula (3-1) to the general formula (3-8), Ar1, A r2 , Ar3, Ar4, X1, X2, and X3 have the same meanings as defined in claim 1.

4. A compound containing triazine and naphthyl according to claim 1, characterized in that: When only one of L1 or L2 is a phenyl group which may be substituted with a cyano group or not, A and B are simultaneously represented by the general formula (2).

5. A compound containing triazine and naphthyl according to claim 1, characterized in that: When only one of L1 or L2 is a phenyl group which is substituted or unsubstituted with a cyano group, A and B are each independently represented by the general formula (2) or (3), and two of X1, X2, and X3 are represented by N.

6. A compound containing triazine and naphthyl according to claim 1, characterized in that: The structure of the compound containing triazine and naphthyl is shown in any one of the general formulas (4-1) to (4-14): In the general formula (4-1) to the general formula (4-14), Ar1, A r2 , Ar3, Ar4, X1, X2, and X3 have the same meanings as defined in claim 1.

7. A triazine and naphthyl-containing compound according to any one of claims 1 to 6, characterized in that: The L1 and L2 are independently selected from a single bond, an o-phenylene group substituted or unsubstituted by a cyano group, an m-phenylene group substituted or unsubstituted by a cyano group, and a p-phenylene group substituted or unsubstituted by a cyano group; Ar1, A r2 , Ar3, Ar4 are each independently represented by the following structure: Any one of.

8. A compound containing triazine and naphthyl according to claim 1, characterized in that: The specific structure of the compound containing triazine and naphthyl is any one of the following structures:

9. An organic electroluminescent device comprising a substrate, a first electrode and a second electrode, wherein a plurality of organic thin film layers are provided between the first electrode and the second electrode, wherein: The organic thin film layer contains the triazine-naphthyl group-containing compound according to any one of claims 1 to 8. Preferably, the organic thin film layer comprises a hole transport region thin film layer, a light emitting region thin film layer and an electron transport region thin film layer, and the electron transport region thin film layer contains the triazine and naphthyl-containing compound according to any one of claims 1 to 8. Preferably, the electron transport region thin film layer comprises an electron transport layer, and the electron transport layer contains the triazine and naphthyl group-containing compound according to any one of claims 1 to 8. Preferably, the hole transport region thin film layer comprises a hole injection layer, a hole transport layer and an electron blocking layer, the electron transport region thin film layer comprises a hole blocking layer, an electron transport layer and an electron injection layer, and the electron transport layer contains the triazine and naphthyl-containing compound according to any one of claims 1 to 8.

10. A display element, characterized in that: The display element includes the organic electroluminescent device according to claim 9.

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