Organic compound, luminescent material, organic electroluminescent device and display panel

Abstract

The invention relates to an organic compound, a luminescent material, an organic electroluminescent device and a display panel, and the organic compound has a structural general formula as shown in formula I. According to the organic compound, dibenzo [A, H] pyrene is used as a core structure unit, the core structure is used as a center, and electron-withdrawing aromatic groups or heteroaromatic groups are symmetrically modified, so that the organic compound is obtained. And an electron-donating aromatic group or heteroaromatic group. The compound has the characteristics of a heat exciton material, the performance of a blue light OLED device is improved, and the service life is prolonged. # imgabs0 #

Description

Technical Field

[0001] The present application relates to the technical field of organic electroluminescence, and in particular to an organic compound, a luminescent material, an organic electroluminescent device and a display panel. Background Art

[0002] OLED (Organic Light-Emitting Diode) devices are devices that use a multi-layer organic thin film structure to generate electroluminescence. Generally speaking, OLED devices are composed of substrates, cathodes, anodes, hole injection layers (HIL), electron injection layers (EIL), hole transport layers (HTL), electron transport layers (ETL) and light-emitting layers (EML). Under the action of the electric field, the holes generated by the anode and the electrons generated by the cathode will move, pass through the hole injection layer and the electron injection layer, and be injected into the hole transport layer and the electron transport layer respectively, and then migrate to the light-emitting layer. When the two meet in the light-emitting layer, energy excitons are generated, thereby exciting the light-emitting molecules to finally produce visible light.

[0003] After nearly three decades of development, OLED has entered the commercial application stage in the field of small and medium-sized display screens. Among them, red and green light materials and technologies have reached commercial application standards, but blue light still faces low brightness and short device life at high brightness. Therefore, it is particularly urgent and important to develop blue light materials that can remain stable at high energy states. Summary of the invention

[0004] Based on this, it is necessary to provide a new type of organic compound. The organic compound is used as a luminescent material, especially as a thermoexciton blue light host material, in an organic luminescent functional layer to realize a high-efficiency and long-life OLED device.

[0005] In the first aspect of the present application, an organic compound having the general structural formula shown in Formula I is provided:

[0006]

[0007] wherein X is independently selected from CR or N at each occurrence, and R is selected from H, D or C1-C6 alkyl;

[0008] Ar1 and Ar2 are each independently selected from a substituted or unsubstituted aromatic group having 5 to 60 ring atoms or a substituted or unsubstituted heteroaromatic group having 5 to 60 ring atoms, and one of Ar1 and Ar2 is an electron withdrawing group and the other is an electron donating group;

[0009] L1 and L2 are each independently selected from a single bond, a substituted or unsubstituted aromatic group having 5 to 30 ring atoms, or a substituted or unsubstituted heteroaromatic group having 5 to 30 ring atoms.

[0010] In some embodiments of the first aspect of the present application, the electron-donating group is selected from: an aromatic group or a nitrogen-containing heteroaromatic group having 5 to 30 ring atoms, an aromatic group or a nitrogen-containing heteroaromatic group having 5 to 30 ring atoms substituted by R1,

[0011] wherein R1 is selected from a substituted or unsubstituted aryl group having 5 to 20 ring atoms, a substituted or unsubstituted nitrogen-containing heteroaryl group having 5 to 20 ring atoms, a substituted or unsubstituted arylamino group having 5 to 20 ring atoms, or a substituted or unsubstituted C1-C6 alkyl group; and / or,

[0012] The electron withdrawing group is selected from: an aromatic group or a nitrogen-containing heteroaromatic group having 5 to 30 ring atoms, an aromatic group or a nitrogen-containing heteroaromatic group having 5 to 30 ring atoms substituted by R2,

[0013] Wherein, R2 is selected from halogen, -CN, -CF3, -NO2, -CO2R 6 、-C(O)R 6 、-S(O)R 6 、-SO2R 6 、-SO3R 6 、-P(O)R 6 ,-PO2R 6 or-PO3R 6 ; R 6 Selected from substituted or unsubstituted C1-C6 alkyl groups.

[0014] In some embodiments of the first aspect of the present application, the electron donating group is selected from the following groups, or groups obtained by mutual substitution or fusion of the following groups:

[0015]

[0016] Among them, X 1 Each occurrence is independently selected from CR 1 or N;

[0017] Y 1 Each occurrence is independently selected from CR 2 R 3 , PR 4 NR 5 , S or O,

[0018] R 1 ~R 5 Each occurrence is independently selected from H, D, substituted or unsubstituted aryl having 5 to 20 ring atoms or substituted or unsubstituted C1-C6 alkyl; and / or

[0019] The electron withdrawing group is selected from the following groups, or groups obtained by mutual substitution or fusion of the following groups:

[0020]

[0021] Among them, X 2 Each occurrence is independently selected from CR 7 or N;

[0022] Y 2 Each time there is a separate CR 8 R 9 , S, O, C(=O) or S(=O)2,

[0023] R 7 ~R 9 Each occurrence is independently selected from H, D, halogen, -CN, -CF3, -NO2, substituted or unsubstituted aryl having 5-20 ring atoms, or substituted or unsubstituted C1-C6 alkyl.

[0024] In some embodiments of the first aspect of the present application, the electron donating group is selected from any one of the following groups:

[0025]

[0026]

[0027] The electron withdrawing group is selected from any one of the following groups:

[0028]

[0029] In some embodiments of the first aspect of the present application, L1 and L2 are each independently selected from a single bond or a phenylene group.

[0030] In some embodiments of the first aspect of the present application, the organic compound is any one of the following structural formulas:

[0031]

[0032]

[0033] In some embodiments of the first aspect of the present application, the method for preparing the organic compound comprises the following steps:

[0034] Using dibenzo[A,H]pyrene as a raw material for bromination reaction, 7,14-dibromodibenzo[A,H]pyrene was prepared;

[0035] Performing a first metal coupling reaction on 7,14-dibromodibenzo[A,H]pyrene and a first aryl borate ester to obtain a compound c;

[0036] Performing a second metal coupling reaction on compound c and a second aryl borate to obtain the organic compound;

[0037] Wherein, the general structural formula of the first aryl borate is shown in Formula A, and the general structural formula of the second aryl borate is shown in Formula B:

[0038]

[0039] According to a second aspect of the present application, a light-emitting material is provided, wherein the light-emitting material comprises the organic compound.

[0040] In a third aspect of the present application, an organic electroluminescent device is provided, wherein the luminescent material of the luminescent layer of the organic electroluminescent device includes the organic compound.

[0041] In a fourth aspect of the present application, a display panel is provided, comprising the organic electroluminescent device.

[0042] Compared with the prior art, this application has the following beneficial effects:

[0043] The organic compound shown in the general formula I provided by the present application has dibenzo[A,H]pyrene as the core structural unit, and symmetrically modifies the electron-withdrawing aromatic group or heteroaromatic group and the electron-donating aromatic group or heteroaromatic group with the core structure as the center. The compound has the characteristics of a hot exciton material, which is conducive to separating the channel of the high triplet exciton reversely crossing to the singlet state and the exciton radiation transition channel, reducing the probability of triplet exciton accumulation and quenching, inhibiting the breakage and decomposition of the chemical bonds of the luminescent material, avoiding the red shift of the light color caused by strong CT and the expansion of the half-peak width of the emission peak, and improving the performance and life of the blue light OLED device. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a schematic diagram of the structure of an OLED device in one embodiment of the present application. DETAILED DESCRIPTION

[0045] The organic compound, luminescent material, organic electroluminescent device and display panel of the present application are further described in detail below in conjunction with specific embodiments. The present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0046] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0047] the term

[0048] Unless otherwise specified or incompatible herewith, the terms and phrases used herein shall have the following meanings:

[0049] In the present application, "substituted" means that a hydrogen atom in a substituted group is replaced by a substituent.

[0050] In this application, "substituted or unsubstituted" means that the defined group may be substituted or unsubstituted. When the defined group is substituted, it should be understood that it is optionally substituted by a group acceptable in the art, including but not limited to: C 1-30 Alkyl, cycloalkyl containing 3-20 ring atoms, heterocyclyl containing 3-20 ring atoms, aryl containing 5-20 ring atoms, heteroaryl containing 5-20 ring atoms, silanyl, carbonyl, alkoxycarbonyl, aryloxycarbonyl, carbamoyl, haloformyl, formyl, -NRR', cyano, isocyano, isocyanate, thiocyanate, isothiocyanate, hydroxyl, trifluoromethyl, nitro or halogen, and the above groups can also be further substituted by substituents acceptable in the art; it is understandable that R in -NR0R0' R0 and R0′ are each independently substituted by an acceptable group in the art, including but not limited to H, C1-C6 alkyl, cycloalkyl containing 3-8 ring atoms, heterocyclyl containing 3-8 ring atoms, aryl containing 5-20 ring atoms or heteroaryl containing 5-10 ring atoms; the C1-C6 alkyl, cycloalkyl containing 3-8 ring atoms, heterocyclyl containing 3-8 ring atoms, aryl containing 5-20 ring atoms or heteroaryl containing 5-10 ring atoms are optionally further substituted by one or more of the following groups: C 1-6 Alkyl, cycloalkyl containing 3 to 8 ring atoms, heterocyclyl containing 3 to 8 ring atoms, halogen, cyano, hydroxy, nitro or amino.

[0051] In the present application, the "number of ring atoms" refers to the number of atoms in the atoms constituting the ring itself of a structural compound (e.g., a monocyclic compound, a condensed ring compound, a cross-linked compound, a carbocyclic compound, a heterocyclic compound) formed by atoms bonding to form a ring. When the ring is substituted by a substituent, the atoms contained in the substituent are not included in the ring atoms. The same is true for the "number of ring atoms" described below unless otherwise specified. For example, the number of ring atoms of a benzene ring is 6, the number of ring atoms of a naphthalene ring is 10, and the number of ring atoms of a thienyl group is 5.

[0052] The term "alkyl" refers to a saturated hydrocarbon containing a primary (normal) carbon atom, or a secondary carbon atom, or a tertiary carbon atom, or a quaternary carbon atom, or a combination thereof. Phrases containing this term, for example, "C1-C6 alkyl" refers to an alkyl group containing 1 to 6 carbon atoms, and each occurrence can be independently C1 alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, C6 alkyl. Suitable examples include, but are not limited to: methyl (Me, -CH3), ethyl (Et, -CH2CH3), 1-propyl (n-Pr, n-propyl, -CH2CH2CH3), 2-propyl (i-Pr, i-propyl, -CH(CH3)2), 1-butyl (n-Bu, n-butyl, -CH2CH2CH2CH3), 2-methyl-1-propyl (i-Bu, i-butyl, -CH2CH(CH3)2), 2-butyl (s-Bu, s-butyl, -CH(CH3) CH2CH3), 2-methyl-2-propyl (t-Bu, t-butyl, -C(CH3)3), 1-pentyl (n-pentyl, -CH2CH2CH2CH2CH3), 2-pentyl (-CH(CH3)CH2CH2CH3), 3-pentyl (-CH(CH2CH3)2), 2-methyl-2-butyl (-C(CH3)2CH2CH3), 3-methyl-2-butyl (-CH(CH3)CH(CH3)2), 3-methyl-1-butyl (-CH2CH 2CH(CH3)2), 2-methyl-1-butyl (-CH2CH(CH3)CH2CH3), 1-hexyl (-CH2CH2CH2CH2CH2CH3), 2-hexyl (-CH(CH3)CH2CH2CH2CH3), 3-hexyl (-CH(CH2CH3)(CH2CH2CH3)), 2-methyl-2-pentyl (-C(CH3)2CH2CH2CH3), 3-methyl-2-pentyl (-CH(CH3)CH(CH3)CH2 CH3), 4-methyl-2-pentyl (-CH(CH3)CH2CH(CH3)2), 3-methyl-3-pentyl (-C(CH3)(CH2CH3)2), 2-methyl-3-pentyl (-CH(CH2CH3)CH(CH3)2), 2,3-dimethyl-2-butyl (-C(CH3)2CH(CH3)2) and 3,3-dimethyl-2-butyl (-CH(CH3)C(CH3)3. The "alkyl" in the present application can be a straight chain alkyl, a branched alkyl or a cycloalkyl.

[0053] In this application, "aryl" and "aromatic group" are equivalent, and refer to an aromatic hydrocarbon group derived from an aromatic ring compound by removing a hydrogen atom, which can be a monocyclic aromatic group, a condensed aromatic group, or a polycyclic aromatic group. For polycyclic rings, at least one is an aromatic ring system. For example, "aryl having 5-20 ring atoms" refers to an aromatic group containing 5 to 20 ring atoms (i.e., carbon atoms). Suitable examples include, but are not limited to: benzene, biphenyl, naphthalene, anthracene, phenanthrene, diphenylene, triphenylene and its derivatives. It is understandable that multiple aromatic groups can also be interrupted by short non-aromatic units (e.g., <10% non-H atoms, such as C, N or O atoms), such as acenaphthene, fluorene, or 9,9-diarylfluorene, triarylamine, diaryl ether system should also be included in the definition of aromatic group.

[0054] In the present application, "heteroaryl" and "heteroaromatic group" are equivalent, which means that at least one carbon atom on the basis of an aryl or aromatic group is replaced by a non-carbon atom, and the non-carbon atom can be an N atom, an O atom, an S atom, an Si atom, a P atom, etc., and can further be an N atom, an O atom and an S atom. For example, "heteroaryl having 5-20 ring atoms" refers to a heteroaryl containing 5-20 ring atoms. Suitable examples include, but are not limited to, furan, benzofuran, thiophene, benzothiophene, pyrrole, pyrazole, triazole, imidazole, oxazole, oxadiazole, thiazole, tetrazole, indole, carbazole, pyrroloimidazole, pyrrolopyrrole, thienopyrrole, thienothiophene, furanopyrrole, furanofuran, thienofuran, benzisoxazole, benzisothiazole, benzimidazole, pyridine, pyrazine, pyridazine, pyrimidine, triazine, quinoline, isoquinoline, o-naphthylidene, quinoxaline, phenanthridine, primidine, quinazoline, and quinazolinone.

[0055] "Halogen" or "halo" refers to F, Cl, Br or I.

[0056] "Arylamino" refers to an amino group in which at least one hydrogen atom is replaced by an aryl group, wherein the aryl moiety may include 5 to 20 carbon atoms. For example, any structure of a monoarylamino group represented by an -NH(aryl) group, a diarylamino group represented by an -N(aryl)(aryl) group. In this case, the aryl groups may be independently the same as those described in the above description of aryl groups. Suitable examples include, but are not limited to, phenylamino groups.

[0057] In the present application, when a linking site is not specified in a group, it means that an optional linking site in the group can be used as a linking site.

[0058] In the present application, when the fusion site is not specified in the group, it means that any fusion site in the group can be used as the fusion site, and preferably two or more sites in the ortho position in the group are fusion sites.

[0059] In the present application, the single bond to which the substituent is connected runs through the corresponding ring, indicating that the substituent can be connected to any position of the ring, for example R is connected to any substitutable position of the benzene ring.

[0060] Traditional blue light OLEDs have uneven distribution of excitons and polarons in the EML layer, and their local concentration is too high, resulting in aggregation, which causes TTA and TPA phenomena and generates high-energy excited state excitons. The chemical covalent bonds of the luminescent material are broken in the high-energy state, causing material decomposition, resulting in a short device life.

[0061] Therefore, in the first aspect of the present application, an organic compound is provided, which has the general structural formula shown in Formula I below:

[0062]

[0063] X is independently selected at each occurrence from CR or N, and R is selected from H, D or C1-C6 alkyl.

[0064] Ar1 and Ar2 are each independently selected from an aromatic group having 5-60 ring atoms, which is substituted or unsubstituted by a substituent selected from the following S1 group, or a heteroaromatic group having 5-60 ring atoms, which is substituted or unsubstituted by a substituent selected from the following S1 group; suitable substituents of the S1 group include, but are not limited to, unsubstituted C1-C6 alkyl, C1-C6 alkyl substituted by halogen, aryl containing 5-20 ring atoms or heteroaryl containing 5-10 ring atoms, wherein the aryl containing 5-20 ring atoms or the heteroaryl containing 5-10 ring atoms is optionally further substituted by one or more of the following groups: C1-C6 alkyl, halogen, cyano, nitro or amino.

[0065] As shown in the general structure of Formula I, one of Ar1 and Ar2 is an electron withdrawing group and the other is an electron donating group. In some embodiments, Ar1 is an electron withdrawing group and Ar2 is an electron donating group. In other embodiments, Ar1 is an electron donating group and Ar2 is an electron withdrawing group.

[0066] L1 and L2 are each independently selected from a single bond, an aromatic group having 5 to 30 ring atoms, which is substituted or unsubstituted by a substituent selected from the following S2 group, or a heteroaromatic group having 5 to 30 ring atoms, which is substituted or unsubstituted by a substituent selected from the following S2 group. Suitable substituents of the S2 group include, but are not limited to, unsubstituted C1-C6 alkyl or C1-C6 alkyl substituted by halogen.

[0067] Optionally, L1 and L2 are each independently selected from a single bond or a phenyl group. In some embodiments, L1 and L2 are both selected from a single bond. In other embodiments, L1 and L2 are both selected from a phenylene group.

[0068] In some embodiments, the electron-donating group is selected from: an aromatic group or a nitrogen-containing heteroaromatic group having 5 to 30 ring atoms, an aromatic group or a nitrogen-containing heteroaromatic group having 5 to 30 ring atoms substituted by R1,

[0069] Wherein, R1 is selected from an aryl group having 5-20 ring atoms which is substituted or unsubstituted by a substituent selected from the following S3 group, a nitrogen-containing heteroaryl group having 5-20 ring atoms which is substituted or unsubstituted by a substituent selected from the following S3 group, an arylamino group having 5-20 ring atoms which is substituted or unsubstituted by a substituent selected from the following S3 group, or a C1-C6 alkyl group which is substituted or unsubstituted by a substituent selected from the following S4 group. Suitable substituents of the S3 group include, but are not limited to, unsubstituted C1-C6 alkyl groups or C1-C6 alkyl groups substituted by halogen. Suitable substituents of the S3 group include, but are not limited to, halogen.

[0070] In some embodiments, R1 is selected from phenyl, phenylamino, diphenylamino or methyl.

[0071] Optionally, the electron donating group is selected from the following groups, or groups obtained by mutual substitution or fusion of the following groups:

[0072]

[0073] Among them, X 1 Each occurrence is independently selected from CR 1 or N;

[0074] Y 1 Each occurrence is independently selected from CR 2 R 3 , PR 4 NR 5 , S or O,

[0075] R 1 ~R 5 Each occurrence is independently selected from H, D, aryl having 5-20 ring atoms substituted or unsubstituted by a substituent selected from the following S5 group, or C1-C6 alkyl substituted or unsubstituted by a substituent selected from the following S6 group. Suitable substituents of the S5 group include, but are not limited to, C1-C6 alkyl. Suitable substituents of the S6 group include, but are not limited to, halogen.

[0076] In some embodiments, R 1 ~R 5 Each occurrence is independently selected from H, D, phenyl or methyl.

[0077] Further optionally, the electron donating group is selected from any one of the following groups:

[0078]

[0079] In some embodiments, the electron withdrawing group is selected from: an aromatic group or a nitrogen-containing heteroaromatic group having 5 to 30 ring atoms, an aromatic group or a nitrogen-containing heteroaromatic group having 5 to 30 ring atoms substituted by R2,

[0080] Wherein, R2 is selected from halogen, -CN, -CF3, -NO2, -CO2R 6 、-C(O)R 6 、-S(O)R 6 、-SO2R 6 、-SO3R 6 、-P(O)R 6 ,-PO2R 6 or-PO3R 6 ; R 6 Selected from C1-C6 alkyl substituted or unsubstituted by a substituent selected from the following S7 group. Suitable substituents of S7 group include, but are not limited to, halogen.

[0081] In some embodiments, R2 is selected from halogen or -CN.

[0082] Optionally, the electron withdrawing group is selected from the following groups, or groups obtained by mutual substitution or fusion of the following groups:

[0083]

[0084] Among them, X 2 Each occurrence is independently selected from CR 7 or N;

[0085] Y 2 Each time there is a separate CR 8 R 9 , S, O, C(=O) or S(=O)2,

[0086] R 7 ~R 9 Each occurrence is independently selected from H, D, halogen, -CN, -CF3, -NO2, aryl having 5-20 ring atoms substituted or unsubstituted by a substituent selected from the following S8 group, or C1-C6 alkyl substituted or unsubstituted by a substituent selected from the following S9 group. Suitable substituents of the S8 group include, but are not limited to, C1-C6 alkyl. Suitable substituents of the S9 group include, but are not limited to, halogen.

[0087] In some embodiments, R 7 ~R 9 Each occurrence is independently selected from H, D, halogen, -CN, -CF3, -NO2, phenyl or methyl.

[0088] Further optionally, the electron withdrawing group is selected from any one of the following groups:

[0089]

[0090] Specifically, the organic compound of the present application can be selected from the following structures but is not limited thereto:

[0091]

[0092]

[0093] The organic compound shown in Formula I in the present application can be prepared according to the following preparation method provided in the present application, but is not limited to the preparation method provided in the present application. The specific preparation method comprises the following steps:

[0094] Using dibenzo[A,H]pyrene as a raw material for bromination reaction, 7,14-dibromodibenzo[A,H]pyrene was prepared;

[0095] The 7,14-dibromodibenzo[A,H]pyrene is subjected to a metal coupling reaction with a first aryl borate ester to prepare a compound c;

[0096] Compound c is subjected to a metal coupling reaction with a second aryl borate ester to obtain the organic compound.

[0097] The general structural formula of the first aryl borate is shown in Formula A, and the general structural formula of the second aryl borate is shown in Formula B:

[0098]

[0099] The definitions of Ar1, Ar2, L1 and L2 are as described above and will not be repeated here.

[0100] In some embodiments, the bromination reagent of the bromination reaction is NBS (N-bromobutanesulfonimide). Optionally, the molar ratio of dibenzo[A,H]pyrene to NBS is 1:(2.5-3.5). Further optionally, the temperature of the bromination reaction is 10°C to 25°C, and the time is 0.5h to 1.5h.

[0101] In some embodiments, the metal coupling reaction of 7,14-dibromodibenzo[A,H]pyrene and the first aryl borate ester refers to a first metal coupling reaction of 7,14-dibromodibenzo[A,H]pyrene and the first aryl borate ester under an inert gas atmosphere and in the presence of a first base and a first catalyst. Optionally, the molar ratio of 7,14-dibromodibenzo[A,H]pyrene to the first aryl borate ester is 1:(0.8-1.4).

[0102] In some embodiments, the first catalyst is Pd(PPh3)4 or Pd2(dba)3.

[0103] In some embodiments, the first base is potassium phosphate or sodium tert-butoxide. Optionally, the molar ratio of 7,14-dibromodibenzo[A,H]pyrene to the first base is 1:(3-8).

[0104] In some embodiments, the temperature of the first metal coupling reaction is 75° C. to 110° C., and the time of the first metal coupling reaction is 12 h to 24 h.

[0105] The solvent for the first metal coupling reaction was ultra-dry THF or anhydrous toluene solvent with 1% tri-tert-butylphosphine added.

[0106] In some embodiments, the metal coupling reaction of compound c and the second aryl borate refers to a first metal coupling reaction of compound c and the second aryl borate in an inert gas atmosphere in the presence of a second base and a second catalyst. Optionally, the molar ratio of compound c to the second aryl borate is 1:(0.8-1.4).

[0107] In some embodiments, the second catalyst is Pd(PPh3)4.

[0108] In some embodiments, the second base is potassium phosphate. Optionally, the molar ratio of compound c to the second base is 1:(3-8).

[0109] In some embodiments, the temperature of the second metal coupling reaction is 75° C. to 90° C., and the time of the second metal coupling reaction is 12 h to 24 h.

[0110] The solvent for the second metal coupling reaction was super dry THF or anhydrous toluene with 1% tri-tert-butylphosphine added.

[0111] The first aryl borate comprises a first aryl group and a borate group, and the first aryl group and the borate group are directly bonded by a chemical bond. The first aryl group can be selected from any aryl group defined in the above organic compound. The second aryl borate comprises a second aryl group and a borate group, and the second aryl group can be selected from any aryl group defined in the above organic compound, and the second aryl group and the borate group are directly bonded by a chemical bond.

[0112] In a second aspect of the present application, a luminescent material is further provided, the luminescent material comprising the organic compound shown in any embodiment of the first aspect of the present application. The organic compound in the present application can preferably be used as a thermoexciton blue light host material.

[0113] The third aspect of the present application further provides an organic electroluminescent device, wherein the light-emitting material of the light-emitting layer of the organic electroluminescent device includes the organic compound shown in any embodiment of the first aspect of the present application.

[0114] The fourth aspect of the present application relates to the application of the organic electroluminescent device according to the third aspect of the present application in various electronic devices, including, but not limited to, display devices, lighting devices, light sources, sensors, and the like.

[0115] The fifth aspect of the present application also relates to electronic devices comprising the organic electroluminescent device according to the third aspect of the present application, including, but not limited to, display devices, lighting devices, light sources, sensors, and the like.

[0116] In some specific embodiments, a display panel is provided, comprising the organic electroluminescent device described above.

[0117] In addition, the organic electroluminescent device of the present application will be described below with reference to the drawings as appropriate.

[0118] The organic electroluminescent device comprises a cathode, an anode and one or more organic functional layers between the cathode and the anode. The organic functional layer is selected from one or more layers of an electron injection layer, an electron transport layer, a hole blocking layer, a hole injection layer, a hole transport layer, an electron blocking layer and a light-emitting layer, wherein at least one light-emitting layer is included. Typically, the organic functional layer comprises a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer and an electron injection layer.

[0119] This application has no particular restrictions on other aspects of the organic electroluminescent device. Figure 1 Schematic diagram of the structure of an organic electroluminescent device as an example. The organic electroluminescent device includes an anode 2, a cathode 4 and an organic functional layer located between the anode 2 and the cathode 4, including a hole injection layer (HIL) 3a, a hole transport layer (HTL) 3b, a light-emitting layer (EML) 3c, an electron transport layer (ETL) 3d, and an electron injection layer (EIL) 3e. Further, the organic electroluminescent device also includes a substrate 1. Preferably, the organic compound in the present application is used as a blue light host material of the light-emitting layer (EML) 3c.

[0120] The device structure of the organic light emitting diode, including the cathode, the anode and the organic functional layer, is further described below, but is not limited thereto.

[0121] The anode may comprise a conductive metal or metal oxide, or a conductive polymer. The anode can easily inject holes into the hole injection layer (HIL) or the hole transport layer (HTL) or the light-emitting layer. In one embodiment, the absolute value of the difference between the work function of the anode and the HOMO energy level or valence band energy level of the light-emitting body in the light-emitting layer or the p-type semiconductor material as the HIL or HTL or the electron blocking layer (EBL) is less than 0.5 eV, preferably less than 0.3 eV, and most preferably less than 0.2 eV. Examples of anode materials include but are not limited to: Al, Cu, Au, Ag, Mg, Fe, Co, Ni, Mn, Pd, Pt, ITO, aluminum-doped zinc oxide (AZO), etc. Other suitable anode materials are known and can be easily selected for use by a person skilled in the art. The anode material can be deposited using any suitable technique, such as a suitable physical vapor deposition method, including radio frequency magnetron sputtering, vacuum thermal evaporation, electron beam (e-beam), etc. In certain embodiments, the anode is patterned. Patterned ITO conductive substrates are commercially available and can be used to prepare devices according to the present invention.

[0122] The cathode may comprise a conductive metal or metal oxide. The cathode can easily inject electrons into the EIL or ETL or directly into the light-emitting layer. In one embodiment, the absolute value of the difference between the work function of the cathode and the LUMO energy level or conduction band energy level of the luminophore in the light-emitting layer or the n-type semiconductor material as the electron injection layer (EIL) or the electron transport layer (ETL) or the hole blocking layer (HBL) is less than 0.5 eV, preferably less than 0.3 eV, and most preferably less than 0.2 eV. In principle, all materials that can be used as cathodes of OLEDs may be used as cathode materials for the device of the present invention. Examples of cathode materials include but are not limited to: Al, Au, Ag, Ca, Ba, Mg, LiF / Al, MgAg alloy, BaF2 / Al, Cu, Fe, Co, Ni, Mn, Pd, Pt, ITO, etc. The cathode material can be deposited using any suitable technique, such as a suitable physical vapor deposition method, including radio frequency magnetron sputtering, vacuum thermal evaporation, electron beam (e-beam), etc.

[0123] Without limitation, the hole injection layer can be at least one of the following materials and their derivatives and materials obtained by doping or passivation: PEODT:PSS (poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid)), HAT-CN (2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene), etc.

[0124] Without limitation, the hole transport layer can be at least one of the following materials and their derivatives and materials obtained by doping or passivation: TFB (poly [(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(4,4'-(N-(4-n-butyl)phenyl)-diphenylamine)]), PVK (polyvinylcarbazole), PFB [N,N'-(4-n-butylphenyl)-N,N'-diphenyl-p-phenylenediamine]-[9,9-di-n-octylfluorenyl-2,7-diyl] copolymer, TPD (N,N'- Bis(3-methylphenyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine), TCTA (4,4',4"-tri(carbazole-9-yl)triphenylamine), TAPC (4,4'-cyclohexylbis[N,N-di(4-methylphenyl)aniline]), Poly-TBP, Poly-TPD, NPB (N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine), CBP (4,4'-bis(9-carbazole)biphenyl), etc.

[0125] Without limitation, the electron injection layer may be at least one of the following materials and their derivatives and materials obtained by doping or passivation: Yb, LiF, lithium oxide, etc.

[0126] Without limitation, the electron transport layer can be at least one of the following materials and their derivatives and materials obtained by doping or passivation: LiQ (8-hydroxylithium phosphate), ET1, metal chelate of 8-hydroxyquinoline, TPBi (1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene), etc.

[0127] The structural formulas of other organic materials involved in this application are as follows:

[0128]

[0129] The organic electroluminescent device described in the present application can be selected from, but not limited to, organic light emitting diodes (OLEDs), organic photovoltaic cells, organic light emitting cells, organic field effect transistors, organic light emitting field effect transistors, organic lasers, organic spintronic devices, organic sensors and organic plasmon emission diodes, etc., with OLED being particularly preferred.

[0130] Example

[0131] Hereinafter, the embodiments of the present application will be described. The embodiments described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. If the techniques or conditions are not specified in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used that do not specify the manufacturer are all conventional products that can be obtained commercially.

[0132] The preparation routes of the target compounds in the following examples are as follows:

[0133]

[0134] Preparation Example 1

[0135] Compound a (5 mmol) was added to a 250 mL two-necked flask, and 100 mL of chloroform was added and placed in an ice bath. NBS (15 mmol) was dissolved in 50 mL of chloroform and slowly added dropwise to the reaction device. After the addition was completed, the mixture was stirred for 10 min in an ice bath, warmed to room temperature and reacted for 1 h. The reaction was quenched with 50 mL of 1 mol / mL sodium thiosulfate aqueous solution, and the reaction solution was extracted and repeatedly washed with dichloromethane (500 mL) and water (200 mL) for 3 to 4 times. The crude product was mixed with 300 to 400 mesh silica gel and separated by column chromatography using PE as the eluent to obtain compound b.

[0136] Compound b (2.5 mmol), raw material 1 (2.5 mmol), Pd(PPh3)4 (0.125 mmol) and potassium phosphate (12.5 mmol) were added to a 250 mL two-necked flask, where raw material 1 was 4-boric acid triphenylamine (CAS: 201802-67-7), and then 100 mL of redistilled tetrahydrofuran was added, nitrogen was introduced, and a vacuum pump was used to evacuate and ventilate for 20 min. The reaction solution was stirred and heated to 85 ° C for 24 h, the reaction was stopped, and the temperature was cooled to room temperature. The reaction solution was extracted, and dichloromethane (800 mL) and water (250 mL) were used for repeated washing 3 to 4 times. The obtained organic phase was dried with anhydrous magnesium sulfate, filtered, concentrated, and separated by column chromatography. The eluent PE / DCM = 10:3, and compound c (whose general structural formula is shown in compound c in the above preparation route, wherein D is a triphenylamine group) was separated.

[0137] Compound c (2.5 mmol), 4-cyanophenylboronic acid (2.5 mmol), Pd(PPh3)4 (0.125 mmol) and potassium phosphate (12.5 mmol) were added to a 250 mL two-necked flask, and then 100 mL of redistilled tetrahydrofuran was added. Nitrogen was introduced and vacuum pumped for 20 min. The reaction solution was stirred and heated to 85 ° C for 24 h. The reaction was stopped and cooled to room temperature. The reaction solution was extracted and repeatedly washed with dichloromethane (800 mL) and water (250 mL) for 3 to 4 times. The obtained organic phase was dried with anhydrous magnesium sulfate, filtered, concentrated, and separated by column chromatography. The eluent PE / DCM = 10:3, and the target compound M1 was separated.

[0138] The synthesis method of Preparation Example 2-9 is similar to that of Preparation Example 1, but the types of raw material 1 and raw material 2 are changed as shown in Table 1.

[0139] Table 1

[0140]

[0141]

[0142] Table 2 lists the H-NMR spectrum data of target compounds M1-M9 prepared in Preparation Examples 1-10.

[0143] Table 2

[0144]

[0145]

[0146] 2. Application Examples

[0147] Example 1

[0148] Device structure: IZO / PEDOT:PPS(35nm) / HTL(40nm)EML(45nm) / ETL(25nm) / Yb(1nm) / Ag(100nm).

[0149] PEDOT:PPS is the hole injection layer, the HTL layer material is Poly-TFB film (CAS: 223569-31-1, purchased from Lumtec.Corp; 5 mg / mL xylene solution), and the EML is the light-emitting layer, in which the light-emitting layer uses a host-guest mixture as the EML (BH:BD=98:2), BH is compound M1, and BD is BD01; LiQ (8-hydroxylithium phosphate) and ET1 (8:2) are the electron transport layer, and Ag is the cathode material.

[0150] The preparation steps of OLED devices are as follows:

[0151] 1. Indium zinc oxide (IZO) coated glass (Specifications: thickness 75nm, sheet resistance 10Ωm -2 , surface size 30mm×30mm) pre-processed

[0152] The cleaning machine was used for program cleaning in sequence, with each cleaning step lasting 120 seconds. The stains and dust on the surface of the ITO glass substrate were thoroughly cleaned and placed on a hot plate at 230°C for 30 minutes. Then, the substrate was placed in an electric hot air drying oven for 24 hours for drying. The dried glass substrate was then exposed to UV light and treated with O2 plasma for 15 minutes to reduce the surface work enthalpy.

[0153] 2. The pretreated ITO glass substrate was used as the device anode. Then, PEDOT:PPS was poured into the inkjet printer cartridge in a nitrogen glove box. 9 pL of HI layer ink was injected into each pixel luminous point, and VD was performed for 3 min (vacuum degree was 1×10 - 4 mPa) to form a 35nm thick HI layer and anneal at 230℃ for 30 minutes. Then the hole transport layer material (concentration of 30mg / ml) dissolved in a mixed solution of xylene and cyclohexylbenzene was filtered and poured into the inkjet printer cartridge. 12 pL of HT layer ink was injected into each pixel luminous point and VD was performed for 7min (vacuum degree of 1×10 -4 mPa) to form a 40nm thick HTL layer, which was annealed at 230℃ for 30 minutes. Then, the dissolved luminescent layer material (concentration 20mg / ml) was prepared into ink and poured into the inkjet printer cartridge. 10 picoliters was injected into each pixel of the HTL layer and VD was performed for 5min (vacuum degree 1×10 - 4 mPa), forming an EML layer, annealing at 140 ° C for 20 min, with a thickness of 35 nm, and then transferring the substrate to a vacuum evaporation chamber (vacuum degree of 5×10 -7 Pa), vacuum evaporation is performed to evaporate 25nm of ETL material onto the EML layer, then 1nm of Yb is evaporated onto the surface of the ETL layer, and finally 100nm thick Ag is evaporated onto the top of the ETL, and finally UV curing and packaging is performed, and heating and baking are performed for 20 minutes.

[0154] The preparation methods of the OLED devices of Examples 2-9 and Comparative Examples 1-8 are similar to those of Example 1, except that the types of the host material and the guest material are changed, as shown in Table 3.

[0155] The current-voltage (JV) characteristics of each OLED device were characterized by a characterization device, and the lifetime (LT90@1000nits), half-width (FWHM) and external quantum efficiency EQE relative values ​​were recorded. The results are shown in Table 3 below. The lifetime LT90@1000nits refers to the time it takes for the brightness of the device to drop from an initial brightness of 1000nits to 95% of the initial brightness under a constant current. The LT90@1000nits and EQE relative values ​​are calculated relative to the OLED of Comparative Example 1, i.e., the lifetime of the OLED of Comparative Example 1 is 1 and the EQE is 1.

[0156] Table 3

[0157]

[0158]

[0159] It can be seen from Table 3 that mixing the thermoexciton material of the present application into the EML layer can significantly improve the lifespan, efficiency and color purity of the OLED device compared to the comparative example.

[0160] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0161] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. An organic compound having the general structural formula shown in Formula I below: in, X is independently selected from CR or N at each occurrence, and R is selected from H, D or C1-C6 alkyl; Ar1 and Ar2 are each independently selected from a substituted or unsubstituted aromatic group having 5 to 60 ring atoms or a substituted or unsubstituted heteroaromatic group having 5 to 60 ring atoms, and one of Ar1 and Ar2 is an electron withdrawing group and the other is an electron donating group; L1 and L2 are each independently selected from a single bond, a substituted or unsubstituted aromatic group having 5 to 30 ring atoms, or a substituted or unsubstituted heteroaromatic group having 5 to 30 ring atoms.

2. The organic compound according to claim 1, characterized in that The electron-donating group is selected from: an aromatic group or a nitrogen-containing heteroaromatic group having 5 to 30 ring atoms, an aromatic group or a nitrogen-containing heteroaromatic group having 5 to 30 ring atoms substituted by R1, wherein R1 is selected from a substituted or unsubstituted aryl group having 5 to 20 ring atoms, a substituted or unsubstituted nitrogen-containing heteroaryl group having 5 to 20 ring atoms, a substituted or unsubstituted arylamino group having 5 to 20 ring atoms, or a substituted or unsubstituted C1-C6 alkyl group; and / or, The electron withdrawing group is selected from: an aromatic group or a nitrogen-containing heteroaromatic group having 5 to 30 ring atoms, an aromatic group or a nitrogen-containing heteroaromatic group having 5 to 30 ring atoms substituted by R2, Wherein, R2 is selected from halogen, -CN, -CF3, -NO2, -CO2R 6 、-C(O)R 6 、-S(O)R 6 、-SO2R 6 、-SO3R 6 、-P(O)R 6 ,-PO2R 6 or-PO3R 6 ; R 6 Selected from substituted or unsubstituted C1-C6 alkyl groups.

3. The organic compound according to claim 1, characterized in that The electron-donating group is selected from the following groups, or groups obtained by mutual substitution or fusion of the following groups: Among them, X 1 Each occurrence is independently selected from CR 1 or N; Y 1 Each occurrence is independently selected from CR 2 R 3 , PR 4 NR 5 , S or O, R 1 ~R 5 Each occurrence is independently selected from H, D, substituted or unsubstituted aryl having 5 to 20 ring atoms or substituted or unsubstituted C1-C6 alkyl; and / or The electron withdrawing group is selected from the following groups, or groups obtained by mutual substitution or fusion of the following groups: Among them, X 2 Each occurrence is independently selected from CR 7 or N; Y 2 Each occurrence has its own independent CR 8 R 9 , S, O, C(=O) or S(=O)2, R 7 ~R 9 Each occurrence is independently selected from H, D, halogen, -CN, -CF3, -NO2, substituted or unsubstituted aryl having 5-20 ring atoms, or substituted or unsubstituted C1-C6 alkyl.

4. The organic compound according to claim 1, characterized in that The electron donating group is selected from any one of the following groups: The electron withdrawing group is selected from any one of the following groups:

5. The organic compound according to claim 1, characterized in that L1 and L2 are each independently selected from a single bond or a phenylene group.

6. The organic compound according to claim 1, characterized in that The organic compound is any one of the following structural formulas:

7. The method for preparing an organic compound according to any one of claims 1 to 6, characterized in that: The following steps are involved: Using dibenzo[A,H]pyrene as a raw material for bromination reaction, 7,14-dibromodibenzo[A,H]pyrene was prepared; Performing a first metal coupling reaction on 7,14-dibromodibenzo[A,H]pyrene and a first aryl borate ester to obtain a compound c; Performing a second metal coupling reaction on compound c and a second aryl borate to obtain the organic compound; Wherein, the general structural formula of the first aryl borate is shown in Formula A, and the general structural formula of the second aryl borate is shown in Formula B:

8. A luminescent material, characterized in that: The light-emitting material comprises the organic compound according to any one of claims 1 to 7.

9. An organic electroluminescent device, characterized in that: The luminescent material of the luminescent layer of the organic electroluminescent device comprises the organic compound according to any one of claims 1 to 7.

10. A display panel, characterized in that: The organic electroluminescent device according to claim 9 is included.

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