Nitrogen-containing heterocyclic compound and organic electroluminescent element comprising same

Abstract

The invention belongs to the technical field of photoelectric materials, and provides a nitrogen-containing heterocyclic compound and an organic electroluminescent element containing the nitrogen-containing heterocyclic compound. A nitrogen-containing heterocyclic compound having a structure # imgabs0 # represented by formula (1), in which X is selected from O or S, R1-R16 are each independently selected from hydrogen, deuterium, halogen, cyano, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted C3-C30 heteroaryl, and in the formula (1), R1-R16 are each independently selected from hydrogen, deuterium, halogen, cyano, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C6-C30 aryl, or substituted or unsubstituted C6-C30 heteroaryl, r1 to R16 independently exist, or two adjacent R1 to R16 are connected to form a ring. The organic electroluminescent element prepared by using the compound can realize reduced driving voltage and durable service life, and the organic electroluminescent element has better performance.

Description

Technical Field

[0001] The present invention belongs to the technical field of optoelectronic materials, and in particular relates to a nitrogen-containing heterocyclic compound and an organic electroluminescent element containing the same. Background Art

[0002] Organic light emitting devices (OLEDs) have the advantages of surface light source, cold light, energy saving, fast response, flexibility, ultra-light and low cost, and their mass production technology is becoming increasingly mature. OLEDs are injection-type light-emitting devices, and their basic structure is to sandwich an organic light-emitting thin film layer between two electrodes with at least one transparent electrode. On this basis, people have developed more complex device structures, especially the introduction of more organic subdivided functional layers; these "functional layers" play a very important role in improving the luminous efficiency and life of the device. The main organic functional layers in organic electroluminescent devices include: hole transport layer (HTL), electron transport layer (ETL), light-emitting layer, hole injection layer, electron injection layer, hole blocking layer, etc.

[0003] Since the electron mobility of the electron transport layer material is much lower than the hole mobility of the hole transport layer material, an imbalance of holes and electrons entering the light-emitting layer occurs, which affects the luminous efficiency and life of the component.

[0004] A series-connected element usually has a charge generation layer between the light-emitting units to ensure that the charge is effectively distributed to the light-emitting stack while improving the current efficiency in each light-emitting layer. Usually, the charge generation layer has a PN junction, in which an N-type charge generation layer and a P-type charge generation layer are stacked in sequence. The injection barrier of electrons from the N-type charge generation layer to the adjacent electron transport layer is relatively large. Therefore, electrons accumulate at the interface between the N-type charge generation layer and the adjacent electron transport layer, which easily causes the interface to deteriorate, shortening the life of the element.

[0005] Therefore, it is urgent to develop new materials for the preparation of charge generation layer to improve the performance of the device. Summary of the invention

[0006] The object of the present invention is to provide a nitrogen-containing heterocyclic compound, wherein an organic electroluminescent element prepared by using the compound can achieve a reduced driving voltage and a durable service life.

[0007] The technical solution adopted by the present invention to solve its technical problem is:

[0008] A nitrogen-containing heterocyclic compound having a structure shown in formula (1) in

[0009] X is selected from O or S,

[0010] R 1 -R 16 Each is independently selected from hydrogen, deuterium, halogen, cyano, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl,

[0011] R 1 -R 16 They exist independently, or two adjacent ones are connected to form a ring.

[0012] Preferably, the compound is selected from any one of formula (1-1), (1-2), (1-3), (1-4),

[0013]

[0014] Preferably, the compound is selected from any one of formula (1-5), (1-6), (1-7), (1-8),

[0015]

[0016] Preferably, R 1 -R 16 Each is independently selected from one of hydrogen, deuterium, halogen, phenyl, biphenyl, naphthyl, pyridyl, bipyridyl or a combination of multiple thereof. A combination of multiple substituents refers to multiple combinations of hydrogen, deuterium, halogen and phenyl, biphenyl, naphthyl, pyridyl, bipyridyl, wherein the combination refers to groups connected by single bonds, such as R 1 Phenyl or deuterated phenyl can be selected.

[0017] Preferably, in the compounds represented by formula (1), (1-1), (1-2), (1-3), (1-4), (1-5), (1-6), (1-7), and (1-8), R 4 , R 5 Linked into a ring, and / or R 12 , R 13 Preferably, the ring C is a six-membered ring; preferably, the ring C is an unsaturated six-membered ring. More preferably, the ring C is a benzene ring.

[0018] Preferably, in the compounds represented by formula (1), (1-1), (1-2), (1-3), (1-4), (1-5), (1-6), (1-7), and (1-8), R 4 and R 5 The phenyl groups are connected to form a benzene ring, and the remaining groups are independently selected from one or a combination of hydrogen, deuterium, halogen, phenyl, biphenyl, naphthyl, pyridyl, bipyridyl.

[0019] Preferably, in the compounds represented by formula (1), (1-1), (1-2), (1-3), (1-4), (1-5), (1-6), (1-7), and (1-8), R 12 and R 13 The phenyl groups are connected to form a benzene ring, and the remaining groups are independently selected from one or a combination of hydrogen, deuterium, halogen, phenyl, biphenyl, naphthyl, pyridyl, bipyridyl.

[0020] Preferably, in formula (1-5), X is selected from O or S, R 8 Selected from pyridyl or deuterated pyridyl, the number of deuterations is 1-4.

[0021] Preferably, in formula (1-6), X is selected from O or S, R 16 Selected from pyridyl or deuterated pyridyl, the number of deuterations is 1-4.

[0022] Preferably, in formula (1-6), X is selected from O or S, R 16 is selected from pyridyl or deuterated pyridyl, wherein the number of deuterated pyridyl is 1-4; R 4 and R 5 Connected to form a benzene ring; R 1 is selected from hydrogen, phenyl or deuterated phenyl, wherein the number of deuterations is 1-5; and the remaining groups are selected from hydrogen or deuterium.

[0023] Preferably, in formula (1-7), X is selected from O or S, R 8 Selected from pyridyl or deuterated pyridyl, the number of deuterations is 1-4.

[0024] Preferably, in formula (1-7), X is selected from O or S, R 8 is selected from pyridyl or deuterated pyridyl, wherein the number of deuterated pyridyl is 1-4; R 12 and R 13 Connected to form a benzene ring; R 9 is selected from hydrogen, phenyl or deuterated phenyl, wherein the number of deuterations is 1-5; and the remaining groups are selected from hydrogen or deuterium.

[0025] Preferably, in formula (1-8), X is selected from O or S, R 4 and R 5 Connected to form a benzene ring, R 12 and R 13 Connected to form a benzene ring, R 1 is selected from hydrogen, phenyl or deuterated phenyl, R 9 is selected from hydrogen, phenyl or deuterated phenyl, and the remaining groups are selected from hydrogen or deuterium.

[0026] Preferably, the compound is selected from any one of the following compounds No. 1-36

[0027]

[0028]

[0029]

[0030] A use of the nitrogen-containing heterocyclic compound of the present invention as an organic electroluminescent element material.

[0031] An organic electroluminescent element comprises an anode, a cathode, and an organic layer located between the anode and the cathode, wherein the organic layer comprises the nitrogen-containing heterocyclic compound of the present invention.

[0032] Preferably, the organic layer comprises an electron transport layer and a light emitting layer, and the electron transport layer comprises the nitrogen-containing heterocyclic compound described in the present invention.

[0033] Preferably, the organic layer comprises more than or equal to two light-emitting units, a charge generation layer is included between the light-emitting units, the light-emitting units comprise an electron transport layer, and at least one charge generation layer and / or at least one electron transport layer comprises the nitrogen-containing heterocyclic compound described in the present invention.

[0034] Preferably, the organic layer comprises more than or equal to two light-emitting units, a charge generation layer is included between the light-emitting units, the light-emitting unit comprises an electron transport layer, the charge generation layer comprises an N-type charge generation layer and a P-type charge generation layer, and at least one of the N-type charge generation layer and the electron transport layer comprises the nitrogen-containing heterocyclic compound described in the present invention.

[0035] The electron transport layer comprises the electron transport layer of each light-emitting unit, and at least one of the N-type charge generation layer and the electron transport layer comprises the nitrogen-containing heterocyclic compound of the present invention, which means that one N-type charge generation layer comprises the nitrogen-containing heterocyclic compound of the present invention; or multiple N-type charge generation layers comprise the nitrogen-containing heterocyclic compound of the present invention; or one electron transport layer in a light-emitting unit comprises the nitrogen-containing heterocyclic compound of the present invention; or one N-type charge generation layer and one electron transport layer in a light-emitting unit comprise the nitrogen-containing heterocyclic compound of the present invention; or one N-type charge generation layer and each electron transport layer in multiple light-emitting units comprise the nitrogen-containing heterocyclic compound of the present invention; or multiple N-type charge generation layers and each electron transport layer in multiple light-emitting units comprise the nitrogen-containing heterocyclic compound of the present invention, etc. When two or more layers comprise the nitrogen-containing heterocyclic compound of the present invention, the nitrogen-containing heterocyclic compounds are the same or different.

[0036] An electronic device comprises the organic electroluminescent element of the present invention.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. The organic electroluminescent compound of the present invention has a benzofuran-substituted phenyl structure, and the phenyl group has an N-containing heteroaryl group at the para position, which can effectively improve the electron injection and transmission capabilities; the organic electroluminescent element prepared using the compound can achieve a reduced driving voltage and a long service life.

[0039] 2. Organic electroluminescent elements have a better lifespan. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the structure of the organic electroluminescent element described in Application Example 1, wherein the first electrode layer 1, the hole injection layer 2, the hole transport layer 3, the light-emitting layer 4, the electron transport layer 5, the N-type charge generation layer 6, the P-type charge generation layer 7, the hole transport layer 8, the light-emitting layer 9, the electron transport layer 10, the electron injection layer 11 and the second electrode layer 12, wherein 100 is the first light-emitting unit and 200 is the second light-emitting unit. DETAILED DESCRIPTION

[0041] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0042] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "include" and / or "include" are used in this specification, it indicates that it is not limited to the content disclosed in this specification.

[0043] In order to more fully describe the present invention to those skilled in the art, embodiments of the present invention are provided. The scope of the present invention is not limited to the following embodiments. These embodiments can make the present invention more thorough and complete, and fully convey the viewpoints of the present invention to those skilled in the art.

[0044] As used herein, the term "halogen" may include fluorine, chlorine, bromine or iodine.

[0045] As used in the present invention, the term "C1-C10 alkyl" refers to a monovalent substituent derived from a straight or branched chain saturated hydrocarbon having 1 to 10 carbon atoms, examples of which include but are not limited to methyl, ethyl, propyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl and hexyl.

[0046] As used in the present invention, the term "C3-C10 cycloalkyl" refers to a monovalent substituent derived from a monocyclic or polycyclic non-aromatic hydrocarbon having 3 to 10 carbon atoms. Examples of such cycloalkyl include, but are not limited to, cyclopropane, cyclobutane, cyclopentane, cyclohexane, norbornyl, adamantane, and the like.

[0047] As used in the present invention, the term "C6-C30 aryl" refers to a monovalent substituent derived from an aromatic hydrocarbon having a monocyclic ring or a combination of two or more rings and having 6 to 30 carbon atoms. Further, such an aryl may have a form in which two or more rings are simply lateral to each other or fused to each other. Examples of such aryl groups include, but are not limited to, phenyl, biphenyl, terphenyl, naphthyl, phenanthrenyl, anthracenyl, pyrenyl, triphenylene, fluoranthenyl, dimethyl 9,9-dimethylfluorene, 9,9-diphenylfluorene, spirobifluorenyl, etc.

[0048] As used in the present invention, the term "C3-C30 heteroaryl group" refers to a monovalent substituent derived from a monocyclic heterocyclic or polycyclic aromatic hydrocarbon having 3 to 30 carbon atoms. In this connection, at least one carbon, preferably 1 to 3 carbons in the ring are substituted with a heteroatom such as N, O, S, P, B or Si. In addition, this heteroaryl group may have a form in which two or more rings are simply lateral to each other or fused to each other or fused to an aromatic group. Examples of such heteroaryl groups include pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, triazinyl, indolizinyl, indolyl, indolopyridinyl, purinyl, phenanthroline, quinolyl, isoquinolyl, quinazolinyl, quinoxalinyl, thiazolyl, imidazolyl, oxazolyl, furanyl, thienyl, benzofuranyl, benzothienyl, benzothiazolyl, benzimidazolyl, benzoxazolyl, carbazolyl, dibenzofuranyl, dibenzothienyl and the like, but the present invention is not limited thereto.

[0049] As used in the present invention, the term "C2-C10 alkenyl" refers to a monovalent substituent derived from a straight or branched unsaturated hydrocarbon having one or more carbon-carbon double bonds and 2 to 10 carbon atoms. Examples thereof include, but are not limited to, vinyl, propenyl, allyl, isopropenyl, 2-butenyl, etc.

[0050] As used in the present invention, the "carbon number is AA-BB" in the expression "Z group having carbon atoms AA-BB" or "Z group having C(AA-BB)" means the carbon number of the Z group when it is unsubstituted, and does not include the carbon number of the substituent when it is substituted. For example, a C6-C30 aryl group means that when it is unsubstituted, the number of carbon atoms in the aryl group is any integer between 6 and 30, that is, the number of carbon atoms when it is unsubstituted can be 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20...30.

[0051] As used in the present invention, the term "substituted" means that a hydrogen atom in a compound is replaced by another substituent. The position where the substitution occurs can be the position where the hydrogen atom is replaced. That is, the position is not limited to a specific position, as long as the hydrogen at the position can be replaced by a substituent. For example, carbazolyl includes any of the following groups, but is not limited thereto, as long as it is not otherwise described in this specification,

[0052]

[0053] Indicates the position of substitution. "Unsubstituted" means that hydrogen atoms remain, in this case, hydrogen atoms include protium, deuterium, tritium.

[0054] When two or more substituents are present, the two or more substituents may be the same or different.

[0055] Unsaturated six-membered ring refers to R 4 With R 5 , R 12 With R 13 pass Link, as shown in the figure Represents the link location.

[0056] As used in the present invention, hydrogen atoms include protium, deuterium and tritium. The compounds of the present invention may contain deuterium atoms of natural origin, or may introduce deuterium atoms by deuterating a portion or all of the raw material compounds. If deuterium atoms are introduced from the raw materials, the deuteration rate may be 100%, or may be less than 100%, or less than 95%, or less than 90%, or less than 80%, and the deuteration rate may also be more than 1%, or more than 5%, or more than 10%. If the deuteration rate is not 100%, it means a mixture of deuterated compounds and undeuterated compounds, or a mixture of completely deuterated compounds and incompletely deuterated compounds, or a mixture of completely deuterated compounds and undeuterated compounds and incompletely deuterated compounds.

[0057] As used in the present invention, terms such as first, second, A, B, etc. are used. The above terms are only used to distinguish components, and do not limit the nature or order of the components to which the terms correspond.

[0058] Organic electroluminescent element

[0059] The structure of the organic electroluminescent element of the present invention is a disclosed structure, comprising an anode, a cathode and an organic layer located between the anode and the cathode, wherein the organic layer comprises a light-emitting layer, and at least one layer of the organic layer comprises the compound of the present invention.

[0060] The organic layer may further include one or more of a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, and an electron injection layer, but is not limited thereto.

[0061] The light-emitting element of the present invention may emit fluorescence or phosphorescence or a combination thereof. The light-emitting element may emit light alone or in series with multiple light-emitting units.

[0062] As simple light emitting elements, the following may be cited, but are not limited thereto:

[0063] (1) hole transport layer / fluorescent light emitting layer / electron transport layer;

[0064] (2) hole transport layer / phosphorescent light emitting layer / electron transport layer;

[0065] (3) hole transport layer / first fluorescent light-emitting layer / second fluorescent light-emitting layer / electron transport layer;

[0066] (4) hole transport layer / first phosphorescent light-emitting layer / second phosphorescent light-emitting layer / electron transport layer;

[0067] (5) hole transport layer / fluorescent emitting layer / spacer layer / phosphorescent emitting layer / electron transport layer;

[0068] (6) hole transport layer / electron blocking layer / fluorescent light emitting layer / electron transport layer;

[0069] (7) hole transport layer / electron blocking layer / fluorescent light emitting layer / hole blocking layer / electron transport layer;

[0070] (8) hole transport layer / electron blocking layer / phosphorescent light emitting layer / electron transport layer;

[0071] (9) hole transport layer / electron blocking layer / phosphorescent emitting layer / hole blocking layer / electron transport layer;

[0072] (10) hole injection layer / hole transport layer / phosphorescent light emitting layer / electron transport layer / electron injection layer;

[0073] (11) hole injection layer / hole transport layer / fluorescent light emitting layer / electron transport layer / electron injection layer;

[0074] (12) hole injection layer / hole transport layer / electron blocking layer / phosphorescent light emitting layer / electron transport layer / electron injection layer;

[0075] (13) hole injection layer / hole transport layer / electron blocking layer / fluorescent light emitting layer / electron transport layer / electron injection layer;

[0076] The phosphorescent / fluorescent light-emitting layers mentioned above can each emit light of a different color.

[0077] As a tandem type organic electroluminescent element, it can be an anode / first light-emitting unit / intermediate layer / second light-emitting unit / cathode. The intermediate layer can also be generally called a charge generation layer, an electron extraction layer, a connecting layer, etc. For example, when stacking a fluorescent light-emitting layer and a phosphorescent light-emitting layer, an intermediate layer is placed between the fluorescent light-emitting layer and the phosphorescent light-emitting layer in order to prevent the excitons generated by the phosphorescent light-emitting layer from diffusing to the fluorescent light-emitting layer or to adjust the balance of carriers.

[0078] When the organic light emitting element includes a plurality of organic material layers, the organic material layers may be formed of the same material or different materials.

[0079] The organic electroluminescent element of the present specification can be manufactured by using materials and methods known in the art, except that one or more of the organic material layers is prepared by using a compound comprising Formula I.

[0080] As the anode material, a material having a relatively large work function may be used, and a transparent conductive oxide, a metal, a conductive polymer, etc. may be used. Specific examples of the anode material include: metals such as vanadium, chromium, copper, zinc, and gold, or alloys thereof; metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); combinations of metals and oxides such as ZnO:Al or SnO2:Sb; conductive polymers such as poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDOT), polypyrrole, and polyaniline, etc., but are not limited thereto.

[0081] As the cathode material, a material with a low work function is generally used to facilitate electron injection into the organic material layer, and metals, metal oxides, conductive polymers, etc. can be used. Specific examples of cathode materials include: metals, such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead, or alloys thereof; multilayer structure materials, such as LiF / Al or LiO2 / Al, etc., but are not limited thereto.

[0082] The hole injection layer is a layer that injects holes from the electrode and has the ability to transport holes. In order to reduce the energy level difference between the electrodes, the hole injection layer is mainly prepared based on aromatic amine compounds, and can also be prepared with the following materials, such as copper phthalocyanine in the metal complex, and HATCN (2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene) with a phenylene structure in the material with the lowest unoccupied molecular orbital energy level. When used as a light-emitting host and dopant, F4-TCNQ (22,3,5,6-tetrafluoro-7,7',8,8'-tetracyanodimethyl-p-benzoquinone) inducer with the lowest unoccupied molecular orbital energy level can be doped in the aromatic amine compound.

[0083] The hole transport material is a layer that receives holes from the hole injection layer and transports the holes to the light-emitting layer, and the hole transport material can appropriately receive holes from the anode or the hole injection layer and transfer the holes to the light-emitting layer. Aromatic amine derivatives, triphenyldiamine derivatives, etc. can be used, and low molecular or high molecular materials can also be used.

[0084] The luminescent material is a material that receives holes and electrons from the hole transport layer and the electron transport layer, respectively, and combines the holes and electrons to emit light in the visible light region. The luminescent layer material includes a host material and a doping material. Red, green or blue luminescent materials can be used, and two or more luminescent materials can be mixed as needed. As the luminescent material, a fluorescent material can be used, and a phosphorescent material can also be used. As the luminescent material, a single component material can be used, and a multi-component material can also be used.

[0085] The electron transport material is a layer that receives electrons from the electron injection layer and transports the electrons to the light-emitting layer, and the electron transport material can receive electrons from the cathode and transfer the electrons to the light-emitting layer. The metal complexes of triazine derivatives, oxadiazole derivatives, benzoquinone and its derivatives, naphthoquinone and its derivatives, anthraquinone and its derivatives, fluorenone derivatives, diphenyl dicyanoethylene and its derivatives, 8-hydroxyquinoline and its derivatives, etc. can be used, and polymer materials and small molecule materials can also be used.

[0086] The electron injection layer is a layer that injects electrons from the electrode. The present application uses LiF, however, the present application is not limited thereto.

[0087] The hole blocking layer is a layer that blocks holes from reaching the cathode.

[0088] The electron blocking layer is a layer that blocks electrons from reaching the anode.

[0089] The organic light-emitting element of the present specification may be a top-emitting element, a bottom-emitting element, or a dual-emission element depending on the materials used.

[0090] The charge generation layer is an intermediate layer between the anode and cathode in a tandem structure element, and is a layer that generates holes and electrons by charge separation. The charge generation layer is usually formed by a P-type layer on the cathode side and an N-type layer on the anode side, and can effectively separate charges and effectively transport carriers.

[0091] Those skilled in the art can synthesize the compounds of the present invention by referring to the synthesis of the following compounds and known synthesis methods.

[0092] The following are specific examples of the synthesis of the compounds of the present invention, but are not limited to the compounds exemplified below. Synthesis Example 1: Synthesis of Compound 15

[0093]

[0094] Step 1: Add raw material 1 (20 g, 71.04 mmol), potassium acetate (20.92 g, 213.12 mmol), bis(triphenylphosphine)palladium dichloride (0.99 g, 1.42 mmol) and diboric acid pinacol ester (23.36 g, 92.35 mmol) to a 500 ml reaction bottle in sequence, and 200 ml of anhydrous dioxane as solvent. After nitrogen replacement, heat to 100 ° C and stir for 2 hours. Monitor the reaction by TLC spot plate. Column purification (pure hexane elution) to obtain intermediate 15-1 (21 g, 63.9 mmol). LC-MS: [M+H] + =329.60

[0095] Step 2: Add raw material 2 (10 g, 32.01 mmol), intermediate 15-1 (10.52 g, 32.01 mmol), sodium carbonate (5.1 g, 48.015 mmol), tetrakis(triphenylphosphine)palladium (0.74 g, 0.64 mmol), 100 ml of tetrahydrofuran and 30 ml of water as solvent to a 500 ml reaction bottle in sequence. After nitrogen substitution, stir at 80 ° C for 12 hours, terminate the reaction, cool to room temperature, separate and discard the aqueous phase. Add anhydrous sodium sulfate to the organic layer, stir the mixture, filter on silica gel, concentrate under reduced pressure, and slurry with 100 mL of ethanol to obtain intermediate 15-2 (11 g, 25.35 mmol).

[0096] LC-MS: [M+H] + =434.90

[0097] Step 3: Add intermediate 15-2 (11 g, 25.35 mmol), potassium acetate (7.46 g, 76.06 mmol), DPPF palladium dichloride (0.37 g, 0.507 mmol) and diboric acid pinacol ester (7.73 g, 30.42 mmol) to a 500 ml reaction bottle in sequence, and 150 ml of anhydrous dioxane as solvent. After nitrogen replacement, heat to 100 ° C and stir for 2 hours. After the reaction is completed, filter, and add 100 ml of n-hexane to the filtrate to obtain intermediate 15-3 (11.31 g, 21.53 mmol).

[0098] LC-MS: [M+H] + =526.42

[0099] Step 4: Add raw material 3 (7.58 g, 22.6 mmol), intermediate 15-3 (11.53 g, 21.53 mmol), sodium carbonate (3.42 g, 32.29 mmol) and tetrakis(triphenylphosphine)palladium (0.52 g, 0.451 mmol) to a 500 ml reaction bottle, 100 ml of tetrahydrofuran and 30 ml of water as solvent. After nitrogen substitution, stir at 80 ° C for 6 hours, terminate the reaction, cool to room temperature, and separate. The organic layer was concentrated and dried under reduced pressure, and recrystallized from toluene to obtain the final product compound 15 (11.96 g, 18.29 mmol).

[0100] LC-MS: [M+H] + =654.75

[0101] 1 H NMR(400MHz,Methylene Chloride-d2)δ8.91(dd,2H),8.81(s,2H),8.71(dt,2H),8.62(ddd,2H),8.46–8.38(m,3H),8.30(d,1H),8.13 (d,1H),7.91–7.77(m,4H),7.74–7.65(m,3H),7.58–7.50(m,2H),7.43(ddt,2H),7.31(ddd,2H),7.10(td,1H).

[0102] The following application examples further illustrate the application of the nitrogen-containing heterocyclic compound of the present invention and the organic electroluminescent element containing the same.

[0103] Application Example 1

[0104] This embodiment provides an organic electroluminescent element, such as Figure 1As shown, it includes a stacked first electrode layer 1, a hole injection layer 2, a hole transport layer 3, a light-emitting layer 4, an electron transport layer 5, an N-type charge generation layer 6, a P-type charge generation layer 7, a hole transport layer 8, a light-emitting layer 9, an electron transport layer 10, an electron injection layer 11 and a second electrode layer 12, wherein 100 is a first light-emitting unit and 200 is a second light-emitting unit.

[0105] The specific component structure is:

[0106] ITO(100nm) / NPD:F4-TCNQ(10%)(10nm) / NPD(120nm) / BH:BD(3%)(20nm) / TmPyPB(10nm) / Bphen:Li(2%)( 10nm) / NPD:F4-TCNQ(10%)(20nm) / NPD(20nm) / BH:BD(3%)(20nm) / Alq3(10nm) / LiF(0.5nm) / Al(200nm).

[0107] Component preparation process:

[0108] The bottom-emitting glass substrate used in this embodiment was purchased from Guangdong Xinli Display Technology Co., Ltd., and 100 nm ITO was used as the first electrode layer 1. First, the bottom-emitting glass substrate was cleaned with ITO cleaning agent, deionized water, and isopropyl alcohol in sequence, and then the bottom-emitting glass substrate was baked at 180 degrees Celsius for 30 minutes to dry it.

[0109] Then put the bottom luminescent glass substrate into the evaporation chamber and place it in a vacuum chamber of about 10 -8In the case of torr, each organic layer is deposited on the ITO anode in sequence by thermal vacuum evaporation at a rate of 0.2-2 angstroms / second. Among them, F4-TCNQ (mass content 10%) is doped into NPD to form a thickness of 10nm as a hole injection layer. NPD is formed to a thickness of 120nm as a hole transport layer, and the anthracene main body ADN (9,10-di(naphtha-2-yl-)anthracene) is doped with a 3% mass content of pyrene dopant 1,6-bis(diphenylamino)pyrene to form a blue light-emitting layer with a thickness of 20nm. TmPyPB is formed to a thickness of 10nm as the first electron transport layer, and BPhen (4,7-Diphenyl-1,10-phenanthroline) is doped with 2% mass content of Li to form an N-type charge generation layer 6 with a thickness of 10nm. F4-TCNQ with a mass content of 10% is doped on NPD. A P-type charge generation layer with a thickness of 20 nm is formed, NPD with a thickness of 20 nm is formed as a hole transport layer, an anthracene main body ADN (9,10-di(naphtha-2-yl-)anthracene) is doped with a pyrene dopant 1,6-bis(diphenylamino)pyrene with a mass content of 3% to form a blue light-emitting layer with a thickness of 20 nm, Alq3 (Tris-(8-hydroxyquinolinato)aluminum) is formed with a thickness of 10 nm as a second electron transport layer, LiF is formed with a thickness of 0.5 nm as an electron injection layer, and Al is formed with a thickness of 200 nm as a cathode.

[0110] Finally, the element was transferred back to the glove box and packaged with a glass cover and a moisture absorbent to complete the element, which was recorded as organic electroluminescent element 1.

[0111]

[0112]

[0113] Contrast structure

[0114] Bphen(4,7-Diphenyl-1,10-phenanthroline)

[0115]

[0116] Examples and Comparative Examples

[0117] Charge Generation Layer The N-type charge generation layer 6 is prepared by using the compound prepared in Example 1 of the present invention instead of the Bphen material, and the organic electroluminescent element 2 is prepared by the same method.

[0118] Life test method: Apply voltage to the obtained organic electroluminescent element so that the current density reaches 30mA / cm 2 The time until the brightness reaches 95% of the initial brightness (LT95 (unit: hour)) was measured.

[0119] The driving voltage is at a current density of 15 mA / cm 2 The following test results are shown in Table 1.

[0120] Table 1

[0121] Driving voltage, v Current efficiency, cd / A Life LT95, hours Organic electroluminescent element 1 7.07 17.53 58 Organic electroluminescent element 2 6.88 17.54 92

[0122] The organic electroluminescent element 2 prepared by using the compound of the present invention has a lower driving voltage and a longer service life than the organic electronic element 1 (using the BPHEN material). Therefore, the compound of the present invention is suitable for preparing high-performance organic electroluminescent elements.

[0123] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0124] The above is a detailed introduction to a nitrogen-containing heterocyclic compound and an organic electroluminescent element containing the same provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A nitrogen-containing heterocyclic compound, characterized in that The compound has the structure shown in formula (1): in X is selected from O or S, R 1 -R 16 Each is independently selected from hydrogen, deuterium, halogen, cyano, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, R 1 -R 16 They exist independently, or two adjacent ones are connected to form a ring.

2. The nitrogen-containing heterocyclic compound according to claim 1, characterized in that The compound is selected from any one of formula (1-1), (1-2), (1-3) and (1-4), 3. The nitrogen-containing heterocyclic compound according to claim 1, characterized in that: R 1 -R 16 Each is independently selected from a combination of one or more of hydrogen, deuterium, halogen, phenyl, biphenyl, naphthyl, pyridyl, and bipyridyl.

4. The nitrogen-containing heterocyclic compound according to claim 2, characterized in that: In the compounds represented by formula (1), (1-1), (1-2), (1-3), and (1-4), R 4 , R 5 Linked into a ring, and / or R 12 , R 13 Connect into ring C.

5. The nitrogen-containing heterocyclic compound according to claim 1, characterized in that The compound is selected from any of the following compounds No. 1-36 6. Use of the nitrogen-containing heterocyclic compound according to any one of claims 1 to 5 as an organic electroluminescent element material. 7 . An organic electroluminescent element, comprising an anode, a cathode, and an organic layer located between the anode and the cathode, wherein the organic layer comprises the nitrogen-containing heterocyclic compound according to claim 1 . 8 . The organic electroluminescent element according to claim 7 , wherein the organic layer comprises an electron transport layer and a light emitting layer, and the electron transport layer comprises the nitrogen-containing heterocyclic compound according to claim 1 .

9. The organic electroluminescent element according to claim 7, wherein the organic layer comprises two or more light-emitting units, a charge generation layer is comprised between the light-emitting units, and the light-emitting units comprise an electron transport layer, wherein: The at least one charge generation layer and / or the at least one electron transport layer comprises the nitrogen-containing heterocyclic compound according to any one of claims 1 to 5.

10. An electronic device comprising the organic electroluminescent element according to any one of claims 7 to 9.

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