Organic electroluminescent element

Abstract

The present invention can provide an organic electroluminescent element comprising: an emission layer including a plurality of hosts and a plurality of dopants; an auxiliary electron transport layer disposed between the emission layer and an electron transport region; and an electron transport layer disposed adjacent to the auxiliary electron transport layer and provided in the electron transport region, wherein the hosts, the dopants, the auxiliary electron transport layer, and the electron transport layer, previously described, are controlled in a coordinated manner so that each has a predetermined energy level and an appropriate energy gap, thereby optimizing the driving voltage, luminous efficiency, and lifespan characteristics of the element.

Description

Organic light-emitting diode

[0001] The present invention relates to an organic electroluminescent device having optimized driving voltage, luminous efficiency, and lifespan characteristics, wherein the device comprises a light-emitting layer including a plurality of hosts and a plurality of dopants, an electron transport auxiliary layer disposed between the light-emitting layer and an electron transport region, and an electron transport layer disposed adjacent to the electron transport auxiliary layer and provided in the electron transport region, wherein the aforementioned host, dopant, electron transport auxiliary layer, and electron transport layer are each organically controlled to have a predetermined energy level and an appropriate energy gap.

[0002]

[0003] Research on organic electroluminescent (EL) devices (hereinafter simply referred to as 'organic EL devices') continued following the blue electroluminescence using anthracene single crystals in 1965. In 1987, Tang proposed an organic EL device with a two-layer stacked structure consisting of a hole layer (NPB) and an emissive layer (Alq3). Subsequently, to achieve the high efficiency and long lifespan characteristics required for commercialization, multilayer stacked structures were proposed that assigned distinct and specialized functions within the device, such as an organic layer responsible for hole injection and transport, an organic layer responsible for electron injection and transport, and an organic layer that induces electroluminescence through the combination of holes and electrons. The introduction of multilayer stacked structures has improved the performance of organic EL devices to commercialization levels, and starting with automotive radio display products in 1997, there is an effort to expand their scope of application to portable information display devices and TV display devices.

[0004] The demand for larger and higher resolution displays presents the challenge of increasing the efficiency and lifespan of organic EL devices. In particular, achieving higher resolution by forming more pixels within the same area results in a reduction in the light-emitting area of ​​organic EL pixels, which inevitably leads to a decrease in lifespan and has become the most critical technical challenge that organic EL devices must overcome.

[0005] When current or voltage is applied to two electrodes of an organic EL device, holes are injected into the organic layer from the anode and electrons are injected into the organic layer from the cathode. When the injected holes and electrons meet, excitons are formed, and these excitons fall to the ground state to emit light. At this time, depending on the type of electron spin of the formed excitons, organic EL devices can be classified into fluorescent EL devices in which singlet excitons contribute to light emission and phosphorescent EL devices in which triplet excitons contribute to light emission.

[0006] The electron spins of excitons formed by the recombination of electrons and holes are generated in singlet excitons and triplet excitons at a ratio of 25% and 75%, respectively. For fluorescent EL devices that emit light through singlet excitons, the internal quantum efficiency theoretically cannot exceed 25% depending on the generation ratio, and the external quantum efficiency is accepted to be limited to 5%. For phosphorescent EL devices that emit light through triplet excitons, the luminescence efficiency can be improved by up to four times compared to fluorescence when metal complex compounds containing transition metal heavy atoms such as Ir and Pt are used as phosphorescent dopants.

[0007] As mentioned above, based on theoretical facts, phosphorescent EL devices exhibit higher efficiency than fluorescence in terms of luminous efficiency. However, regarding blue phosphorescent devices excluding green and red, the level of development for deep blue color purity, high-efficiency phosphorescent dopants, and hosts with a wide energy gap that satisfy these requirements is insufficient, so blue phosphorescent devices have not yet been commercialized and blue fluorescent devices are being used in products.

[0008] Research results have been reported to increase the stability of the device by preventing holes from diffusing into the electron transport layer in order to improve the characteristics of the aforementioned organic EL device. However, satisfactory results have not been obtained to date.

[0009]

[0010] The present invention was devised to solve the aforementioned problems, and its technical objective is to provide an organic electroluminescent device that simultaneously exhibits high efficiency, low voltage, and long lifespan by precisely controlling the light-emitting layer, the electron transport auxiliary layer, and the electron transport layer constituting the organic electroluminescent device to each have a predetermined energy level and an appropriate energy gap between them. In particular, the present invention was completed by discovering that the lifespan of the device can be maximized when the adjacently arranged electron transport layer and the electron transport auxiliary layer have appropriate energy levels and satisfy sufficient electrical properties.

[0011] Other objects and advantages of the present invention may be more clearly explained by the following detailed description of the invention and claims.

[0012]

[0013] To achieve the above-mentioned technical problem, the present invention relates to an organic electroluminescent device having a structure in which a first electrode; a hole transport region; a light-emitting layer; an electron transport region and a second electrode are sequentially stacked, wherein

[0014] It includes an electron transport auxiliary layer disposed between the light-emitting layer and the electron transport region,

[0015] The light-emitting layer comprises a first host, a second host, a first dopant, and a second dopant that are different from each other, and

[0016] The first dopant above is a phosphorescent dopant containing platinum, and

[0017] The above second dopant is a fluorescent dopant containing boron, and

[0018] The superimposed emission wavelength of the first dopant and the second dopant is 10 nm or more, and

[0019] The first host (H1), the second host (H2), the first dopant (D1), and the second dopant (D2) each satisfy the conditions of the following equations (i) to (iv), and

[0020] (i) HOMO H1 < 5.5 eV

[0021] (ii) HOMO H2 ≥ 5.5 eV

[0022] (iii) 440 ≤ λmax D1 ≤ 490

[0023] (iv) 450 ≤ λmax D2 ≤ 500

[0024] (In the above formula, HOMO H1 and HOMO H2 ε₀ is the absolute value of the HOMO energy levels of the first host material and the second host material calculated according to the Gaussian, respectively, and λmax D1 and λmax D2 is the maximum emission wavelength of the first dopant material and the second dopant material, respectively.

[0025] The above electron transport region comprises an electron transport layer disposed adjacent to the above electron transport auxiliary layer, wherein

[0026] The above electron transport auxiliary layer comprises a compound represented by the following chemical formula 5, and

[0027] The above electron transport auxiliary layer (aETL) and the above electron transport layer (ETL) satisfy the conditions of the following equation (xi), and

[0028] (xi) 0 ≤ LUMO ETL - LUMO aETL ≤ 0.2 eV

[0029] (In the above equation, LUMO ETL is the absolute value of the LUMO energy level of the electron transport layer material calculated according to the Gaussian, and LUMO aETL is the absolute value of the LUMO energy levels of the electron transport auxiliary layer material calculated according to the Gaussian),

[0030] The triplet energy (T1) of the first host mentioned above H1 ), triplet energy of the second host (T1 H2 ), triplet energy (T1 of the electron transport auxiliary layer aETL ), and the triplet energy (T1) of the electron transport layer ETL The present invention provides an organic electroluminescent device characterized by all having a voltage of 2.7 eV or higher.

[0031] [Chemical Formula 5]

[0032]

[0033] In the above chemical formula 5,

[0034] Y4 to Y6 are identical or different from each other, and each independently N or CR 31 However, at least one of Y4 to Y6 is N, and

[0035] R 12 , R 31 , Ar8 and Ar9 are identical or different from each other, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group,

[0036] v is an integer from 1 to 4, and

[0037] L is a single bond, or C6~C 18 Selected from the group consisting of an arylene group and a heteroarylene group having 5 to 18 nuclei,

[0038] A is C, Si, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group,

[0039] The arylene group and heteroarylene group of the above L, and the above R 12 , R 31 , the alkyl groups, alkenyl groups, alkynyl groups, aryl groups, heteroaryl groups, aryloxy groups, alkyloxy groups, cycloalkyl groups, heterocycloalkyl groups, alkylsilyl groups, arylsilyl groups, alkylboron groups, arylboron groups, arylphosphine groups, arylphosphine oxide groups, and arylamine groups of Ar8~Ar9 and A are each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C1~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other.

[0040] For example, in one embodiment according to the present invention, the singlet energy (S1) of the first host H1 ) and the singlet energy of the second host (S1 H2 All energies can be 3.2 eV or higher.

[0041] For example, in one embodiment according to the present invention, the triplet energy (T1) of the first host H1 ) and the triplet of the second host (T1 H2 All energies can be 2.8 eV or higher.

[0042] For example, in one embodiment according to the present invention, the mixing ratio of the first host and the second host may be a weight ratio of 2:8 to 8:2.

[0043] For example, in one embodiment according to the present invention, the first host may be a hole-transporting compound that does not contain an electron-transporting moiety, and the second host may be an electron-transporting compound that contains at least one electron-transporting moiety.

[0044] For example, in one embodiment according to the present invention, the second dopant may have an absorption wavelength that overlaps with the emission wavelength of the first dopant by 10 nm or more.

[0045] For example, in one embodiment according to the present invention, the first dopant may be included in an amount of 15 weight% or less based on 100 weight% of the light-emitting layer.

[0046] For example, in one embodiment according to the present invention, the second dopant may be included in an amount of 4 weight% or less based on 100 weight% of the light-emitting layer.

[0047] For example, in one embodiment according to the present invention, the content ratio of the total host and the total dopant in the light-emitting layer may be a weight ratio of 70:30 to 99.5:0.5.

[0048] For example, in one embodiment according to the present invention, the electron transport auxiliary layer (aETL) may include a material satisfying the conditions of the following formulas (v) to (vii).

[0049] (v) HOMO aETL ≥ 5.5 eV

[0050] (vi) LUMO aETL ≤ 2.0 eV

[0051] (vii) T1 aETL ≥ 2.8 eV

[0052] (In the above formula, HOMO aETL , LUMO aETL and T1 aETL ε₀ are the absolute values ​​of the HOMO energy levels, LUMO energy levels, and triplet energies of the electron transport auxiliary layer material calculated according to the Gaussian, respectively).

[0053] In one embodiment according to the present invention, the first host (H1) and the electron transport auxiliary layer (aETL) can satisfy the condition of the following equation (viii).

[0054] (viii) HOMO aETL - HOMO H1 ≥ 0.3 eV

[0055] (In the above formula, HOMO aETL silver It is the absolute value of the HOMO energy levels of the electron transport auxiliary layer material calculated according to the Gaussian, and HOMO H1 is the absolute value of the HOMO energy level of the first host material calculated according to the Gaussian.

[0056] For example, in one embodiment according to the present invention, the first host (H1) and the electron transport auxiliary layer (aETL) can satisfy the condition of the following formula (ix).

[0057] (ix) LUMO aETL - LUMO H1 ≥ 0.3 eV

[0058] (In the above equation, LUMO aETL silver It is the absolute value of the LUMO energy levels of the electron transport auxiliary layer material calculated according to the Gaussian, and LUMO H1 is the absolute value of the LUMO energy level of the first host material calculated according to the Gaussian.

[0059] In one embodiment according to the present invention, the second host (H2) and the electron transport auxiliary layer (aETL) can satisfy the condition of the following equation (x).

[0060] (x) LUMO aETL - LUMO H2 ≤ 0.2 eV

[0061] (In the above equation, LUMO aETL silver It is the absolute value of the LUMO energy level of the electron transport auxiliary layer material calculated according to the Gaussian formula, and LUMO H2 is the absolute value of the LUMO energy level of the second host material calculated according to the Gaussian.

[0062] In one embodiment according to the present invention, the electron transport layer (ETL) may satisfy the conditions of the following formulas (xii) to (xiv).

[0063] (xii) HOMO ETL ≥ 5.7 eV

[0064] (xiii) LUMO ETL ≤ 2.1 eV

[0065] (xiv) T1 ETL ≥2.8 eV

[0066] (In the above formula, HOMO ETL , LUMO ETL and T1 ETL ε₀ are the absolute values ​​of the HOMO energy levels, LUMO energy levels, and triplet energies of the electron transport layer material calculated according to the Gaussian, respectively).

[0067] For example, in one embodiment according to the present invention, the electron transport region comprises at least one layer including an electron transport layer, and based on the electron transport auxiliary layer, may include an electron transport layer or an electron transport layer and an electron injection layer.

[0068] For example, in one embodiment according to the present invention, the hole transport region may include at least one of a hole injection layer, a hole transport layer, a hole transport auxiliary layer, and a light-emitting auxiliary layer.

[0069] For example, in one embodiment according to the present invention, the organic electroluminescent device comprises a plurality of light-emitting layer stacks including at least one light-emitting layer, and the at least one light-emitting layer may include the first host, the second host, the first dopant, and the second dopant.

[0070]

[0071] According to one embodiment of the present invention, by adjusting the light-emitting layer, the electron transport auxiliary layer, and the electron transport layer that are arranged adjacent to each other to each have physical properties such as a predetermined HOMO energy, LUMO energy, and triplet energy (T1), and at the same time precisely controlling the energy gap between them, an organic electroluminescent device with optimized driving voltage, luminous efficiency, and lifetime characteristics can be provided.

[0072] The effects according to the present invention are not limited to those exemplified above, and a wider variety of effects are included in this specification.

[0073]

[0074] FIG. 1 is a cross-sectional view showing the structure of an organic electroluminescent device according to one embodiment of the present invention.

[0075] <Explanation of Symbols>

[0076] 100: Organic electroluminescent device

[0077] A: Organic layer

[0078] 10: First electrode

[0079] 20: Second electrode

[0080] 30: Precision Transport Area

[0081] 31: Hole injection layer

[0082] 32: Precision Transport Layer

[0083] 40: Emissive layer

[0084] 50: Electronic transport area

[0085] 53: Electron transport auxiliary layer

[0086] 52: Electron transport layer

[0087] 51: Electron injection layer

[0088]

[0089] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Accordingly, in some embodiments, well-known process steps, well-known device structures, and well-known techniques are not specifically described to avoid the present invention being interpreted ambiguously. Throughout the specification, like reference numerals refer to like components.

[0090] Unless otherwise defined, all terms used in this specification (including technical and scientific terms) may be used in a meaning commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless explicitly and specifically defined otherwise.

[0091] Furthermore, throughout the specification, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. Also, throughout the specification, the terms "above" or "on" mean not only cases where a part is located above or below the subject part but also cases where another part is located in between, and do not necessarily mean that it is located above based on the direction of gravity. Furthermore, in this specification, terms such as "first," "second," etc., are used to distinguish components from one another, rather than indicating an arbitrary order or importance.

[0092] In this specification, HOMO energy (HOMO, Highest Occupied Molecular Orbital), LUMO energy (LUMO, Lowest Unoccupied Molecular Orbital), triplet energy (T1), and singlet energy (S1) each refer to values ​​calculated according to a Gaussian and converted into absolute values. In addition, in this specification, the maximum emission wavelength (λmax) refers to the emission wavelength range based on the maximum emission peak.

[0093] In addition, in the present invention, "number of nuclei" refers to the number of ring atoms constituting a ring structure, and said nuclei may be carbon or heteroatoms selected from the group consisting of N, O, S, and Se. For example, the number of nuclei of pyridine refers to 6, including 5 C and 1 N constituting the pyridine ring.

[0094] In the present invention, "alkyl" refers to a monovalent substituent derived from a straight-chain or side-chain saturated hydrocarbon having 1 to 40 carbon atoms. Examples thereof include, but are not limited to, methyl, ethyl, propyl, isobutyl, sec-butyl, pentyl, iso-amyl, hexyl, etc.

[0095] In the present invention, "alkenyl" refers to a monovalent substituent derived from a straight-chain or side-chain unsaturated hydrocarbon having 2 to 40 carbon atoms and having one or more carbon-carbon double bonds. Examples thereof include vinyl, allyl, isopropenyl, 2-butenyl, etc., but are not limited thereto.

[0096] In the present invention, "alkynyl" refers to a monovalent substituent derived from a straight-chain or side-chain unsaturated hydrocarbon having 2 to 40 carbon atoms and having one or more carbon-carbon triple bonds. Examples thereof include, but are not limited to, ethynyl and 2-propynyl.

[0097] In the present invention, "aryl" refers to a monovalent substituent derived from an aromatic hydrocarbon having 6 to 40 carbon atoms, consisting of a single ring or a combination of two or more rings. Additionally, forms in which two or more rings are simply penantated or condensed may also be included. Examples of such aryls include, but are not limited to, phenyl, naphthyl, phenanthryl, and anthryl.

[0098] In the present invention, "heteroaryl" refers to a monovalent substituent derived from a monoheterocyclic or polyheterocyclic aromatic hydrocarbon having 5 to 40 nuclei. In this case, one or more carbons in the ring, preferably 1 to 3 carbons, are substituted with heteroatoms selected from the group consisting of N, O, S, and Se. Additionally, forms in which two or more rings are simply pendent or condensed with each other may be included, and furthermore, forms condensed with an aryl group may also be included. Examples of such heteroaryls include, but are not limited to, 6-membered monocyclic rings such as pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, and triazinyl; polycyclic rings such as phenoxathienyl, indolizinyl, indolyl, purinyl, quinolyl, benzothiazole, and carbazolyl; and 2-furanyl, N-imidazolyl, 2-isoxazolyl, 2-pyridinyl, and 2-pyrimidinyl.

[0099] In the present invention, "aryloxy" refers to a monovalent substituent represented by RO-, where R means an aryl having 5 to 40 carbon atoms. Examples of such aryloxy include phenyloxy, naphthyloxy, diphenyloxy, etc., but are not limited thereto.

[0100] In the present invention, "alkyloxy" refers to a monovalent substituent represented by R'O-, where R' represents an alkyl group having 1 to 40 carbon atoms, and may include a linear, branched, or cyclic structure. Examples of alkyloxy include, but are not limited to, methoxy, ethoxy, n-propoxy, 1-propoxy, t-butoxy, n-butoxy, pentoxy, etc.

[0101] In the present invention, "arylamine" means an amine substituted with an aryl group having 6 to 40 carbon atoms.

[0102] In the present invention, "cycloalkyl" refers to a monovalent substituent derived from a monocyclic or polycyclic non-aromatic hydrocarbon having 3 to 40 carbon atoms. Examples of such cycloalkyls include, but are not limited to, cyclopropyl, cyclopentyl, cyclohexyl, norbornyl, and adamantine.

[0103] In the present invention, "heterocycloalkyl" refers to a monovalent substituent derived from a non-aromatic hydrocarbon having 3 to 40 nuclei, wherein one or more carbons in the ring, preferably 1 to 3 carbons, are substituted with heteroatoms such as N, O, S, or Se. Examples of such heterocycloalkyls include, but are not limited to, morpholine and piperazine.

[0104] In the present invention, "alkylsilyl" means a silyl substituted with an alkyl group having 1 to 40 carbon atoms, and "arylsilyl" means a silyl substituted with an aryl group having 5 to 40 carbon atoms.

[0105] In the present invention, "condensed ring or condensed ring" means a condensed aliphatic ring, a condensed aromatic ring, a condensed heteroaliphatic ring, a condensed heteroaromatic ring, or a combination thereof.

[0106]

[0107] Organic Electroluminescent Device

[0108] Hereinafter, preferred embodiments of an organic electroluminescent device according to the present invention will be described with reference to the attached drawings. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below.

[0109] FIG. 1 is a cross-sectional view schematically showing the structure of an organic electroluminescent device (100) according to one embodiment of the present invention.

[0110] Referring to FIG. 1, the organic electroluminescent device (100) comprises: a first electrode (10); a second electrode (20); a light-emitting layer (40) located between the first electrode (10) and the second electrode (20); a hole transport region (30) located between the first electrode (10) and the light-emitting layer (40); and an electron transport region (50) located between the light-emitting layer (40) and the second electrode (20), and further comprises an electron transport auxiliary layer (53) between the light-emitting layer (40) and the electron transport region (50), wherein a plurality of hosts, a plurality of dopants constituting the light-emitting layer (40), and the electron transport auxiliary layer (53) are each organically controlled to have physical properties such as a predetermined HOMO energy, LUMO energy, triplet energy (T1), maximum light emission wavelength, etc., described later, and an appropriate energy gap between them.

[0111] Specifically, in the present invention, a light-emitting layer, an electron transport assist layer, and an electron transport layer are sequentially arranged, wherein the light-emitting layer includes a first host (H1) and a second host (H2) having a predetermined HOMO energy, and a first dopant (D1) and a second dopant (D2) having a predetermined maximum light-emitting wavelength as essential components, and the electron transport assist layer including a specific compound described later and the electron transport layer adjacent thereto are controlled to have a predetermined LUMO energy difference, and at the same time, each material of the first host, second host, electron transport assist layer, and electron transport layer described above is precisely controlled to have a specific triplet energy, e.g. 2.7 eV or more, thereby optimizing the overall efficiency and lifespan characteristics of the device.

[0112] Currently, the red and green light-emitting layers of organic electroluminescent devices utilize phosphorescent materials, respectively, and their technological maturity is high. In contrast, blue phosphorescent materials are still under development, resulting in a high barrier to entry. Thus, while the blue light-emitting layer has significant development potential, the relatively high technical difficulty limits the improvement of the overall performance of blue phosphorescent devices equipped with it.

[0113] Meanwhile, when the organic electroluminescent device is a blue phosphorescent light-emitting device, the color purity and luminous efficiency of the device vary depending on the triplet energy levels of each material constituting the first host, the second host, the electron transport auxiliary layer, and the electron transport layer. As described above, when the triplet (T1) energy of the first host, the second host, the electron transport auxiliary layer, and the electron transport layer materials constituting the light-emitting layer is all adjusted to 2.7 eV or higher, sky blue light can be emitted among blue light, and specifically, when it is 2.8 eV or higher, deep blue light with higher color purity can be emitted. Accordingly, the present invention can significantly improve the luminescence and color purity characteristics of conventional blue phosphorescent devices, which have limitations in development.

[0114] Hereinafter, the configuration of an organic electroluminescent device (100) according to one embodiment of the present invention having the above-described configuration will be explained in more detail.

[0115] substrate

[0116] In the organic electroluminescent device according to the present invention, the substrate may be any substrate commonly used in the field of organic electroluminescent devices without limitation. Considering the mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water resistance of the organic electroluminescent device, it is preferable to use a glass substrate or a transparent plastic substrate.

[0117] First electrode

[0118] In the organic electroluminescent device (100) according to the present invention, the first electrode (10) is disposed on a substrate and acts as an anode that injects holes into the organic layer (A).

[0119] This first electrode (10) may be made of a material with a relatively high work function and, accordingly, becomes an anode that injects holes into an adjacent hole transport region (30). In this case, the second electrode (20) positioned opposite the first electrode (10) becomes a cathode that injects electrons into an adjacent electron transport region (50). However, it is not limited thereto, and depending on the case, the first electrode (10) may be a cathode and the second electrode (20) may be an anode.

[0120] The material forming the first electrode (10) is not particularly limited and may use conventional materials known in the industry. Non-limiting examples include metals such as vanadium, chromium, copper, zinc, and gold; 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 and SnO2:Sb; conductive polymers such as polythiophene, poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDT), polypyrrole, and polyaniline; and carbon black.

[0121] The method of manufacturing the first electrode (10) is not particularly limited and can be manufactured according to conventional methods known in the industry. For example, a method of coating an anode material on a substrate made of a silicon wafer, quartz, glass plate, metal plate, or plastic film may be used.

[0122] Second electrode

[0123] In the organic electroluminescent device (100) according to the present invention, the second electrode (20) is a portion positioned opposite to the first electrode (10) described above, specifically positioned on an electron transport region (50) and serves as a cathode that injects electrons into the organic layer (A).

[0124] The material forming the second electrode (20) is not particularly limited and can use conventional materials known in the industry. Non-limiting examples include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead; alloys thereof; and multilayer materials such as LiF / Al and LiO2 / Al.

[0125] In this case, the second electrode (20) is a (semi)transparent electrode, and the organic electroluminescent device including the second electrode (20) may have a front-emitting structure. At this time, light generated from the light-emitting layer (40) may pass through the second electrode (20), but may also be reflected from the lower surface of the second electrode (20), and accordingly, may be repeatedly reflected between the upper surface of the first electrode (10) and the lower surface of the second electrode (20).

[0126] The method of manufacturing the second electrode (20) is also not particularly limited and can be manufactured according to methods known in the industry.

[0127] organic layer

[0128] The organic layer (A) included in the organic electroluminescent device according to the present invention may use a conventional configuration used as an organic layer of a conventional organic EL device without limitation, and may include, for example, one or more selected from the group consisting of a hole transport region (30), a light-emitting layer (40), and an electron transport region (50). At this time, considering the characteristics of the organic electroluminescent device, it is preferable to include all of the aforementioned organic layers.

[0129] Precision transport area

[0130] The hole transport region (30) included in the organic layer (A) of the present invention serves to move holes injected from the first electrode (10) to the light-emitting layer (40). This hole transport region (30) may include one or more selected from the group consisting of a hole injection layer (31), a hole transport layer (32), an electron blocking layer (hole transport auxiliary layer, not shown), and a light-emitting auxiliary layer (not shown). At this time, considering the characteristics of the organic electroluminescent device, it is preferable to include the hole injection layer (31) and the hole transport layer (32).

[0131] The material forming the aforementioned hole injection layer (31) and hole transport layer (32) is not particularly limited as long as it is a material with a low hole injection barrier and high hole mobility, and any hole injection layer / transport layer material used in the industry can be used without limitation. At this time, the material forming the hole injection layer (31) and hole transport layer (32) may be the same or different from each other.

[0132] The hole injection material mentioned above may be any hole injection material known in the art without limitation. Non-limiting examples of usable hole injection materials include phthalocyanine compounds such as copper phthalocyanine; DNTPD (N,N'-diphenyl-N,N'-bis-[4-(phenyl-m-tolyl-amino)-phenyl]-biphenyl-4,4'-diamine), m-MTDATA (4,4',4"-tris(3-methylphenylphenylamino) triphenylamine), TDATA(4,4'4"-Tris(N,N-diphenylamino)triphenylamine), 2TNATA(4,4',4"-tris{N,-(2-naphthyl)-N-phenylamino}-triphenylamine), PEDOT / PSS(Poly(3,4-ethylenedioxythiophene) / Poly(4-styrenesulfonate)), PANI / DBSA (Polyaniline / Dodecylbenzenesulfonic acid), PANI / CSA (Polyaniline / Camphor sulfonicacid), and PANI / PSS ((Polyaniline) / Poly(4-styrenesulfonate)) can be used individually. Or, two or more types can be mixed.

[0133] In addition, the hole transport material mentioned above may be any hole transport material known in the art without limitation. Non-limiting examples of usable hole transport materials include carbazole derivatives such as phenylcarbazole and polyvinylcarbazole, fluorene derivatives, triphenylamine derivatives such as TPD (N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine) and TCTA (4,4',4"-tris(N-carbazolyl)triphenylamine), NPB (N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine), and TAPC (4,4'-Cyclohexylidene bis[N,N-bis(4-methylphenyl)benzenamine]). These may be used individually or in combination of two or more types.

[0134] The hole transport region (30) can be manufactured using conventional methods known in the art. Examples include vacuum deposition, spin coating, casting, LB method (Langmuir-Blodgett), inkjet printing, laser printing, and laser induced thermal imaging (LITI), but are not limited thereto.

[0135] The thickness of the hole transport region (30) can be appropriately adjusted within a normal range known in the art, for example, from 100 Å to about 2000 Å. If the hole transport region (30) includes an electron blocking layer (hole transport auxiliary layer), a hole transport layer, or any combination thereof, the thickness of the electron blocking layer (hole transport auxiliary layer) is about 50 Å to about 400 Å, and in this case, the thickness of the hole transport layer (32) can be about 50 Å to about 1600 Å. When the thicknesses of the hole transport region (30), the electron blocking layer (hole transport auxiliary layer), and the hole transport layer (32) satisfy the aforementioned ranges, satisfactory hole transport characteristics can be obtained without a substantial increase in driving voltage.

[0136] light-emitting layer

[0137] The light-emitting layer (40) included in the organic layer (A) of the present invention is a layer in which holes and electrons meet to form excitons, and the color of light emitted by the organic electroluminescent device may vary depending on the material forming the light-emitting layer (40).

[0138] Generally, the light-emitting layer is configured to include a single host and a dopant, or a plurality of hosts and a single dopant, or a single host and a plurality of dopants. In contrast, the light-emitting layer (40) of the present invention is differentiated from conventional organic electroluminescent devices in that it necessarily includes a plurality of hosts and a plurality of dopants, and the plurality of hosts and the plurality of dopants are each controlled to have physical properties such as a predetermined HOMO energy level (IP), triplet energy (T1), and / or maximum emission wavelength.

[0139] The plurality of hosts constituting the light-emitting layer (40) of the present invention include at least two hosts that are different from each other, specifically including a first host (H1) and a second host (H2).

[0140] For example, the first host (H1) and the second host (H2) may each satisfy the conditions of the following equations (i) and (ii).

[0141] (i) HOMO H1 < 5.5 eV

[0142] (ii) HOMO H2 ≥ 5.5 eV

[0143] In the above equation, HOMO H1 and HOMO H2 is the absolute value of the HOMO energy levels of the first host material and the second host material calculated according to the Gaussian, respectively.

[0144] When the first host (H1) and the second host (H2) have the aforementioned HOMO energy levels, the charge balance within the light-emitting layer can be improved and efficient charge recombination characteristics can be exhibited due to the mixing of multiple types of hosts. Specifically, the absolute value of the HOMO energy level of the first host (H1) [HOMO H1 ] may be 5.4 eV or less, and the absolute value of the HOMO energy level of the second host (H2) [HOMO H2 ] may be 5.51 eV or higher. Here, the absolute lower limit of the HOMO energy level of the first host (H1) and the absolute upper limit of the HOMO energy level of the second host (H2) are not specifically limited.

[0145] As another specific example, the triplet energy (T1) of the first host mentioned above H1 ) and the triplet energy (T1 of the second host) H2 ) can all be 2.8 eV or higher.

[0146] When the first host (H1) and the second host (H2) have the aforementioned triplet (T1) energy values, the movement of excitons to other layers is prevented, thereby exhibiting an effect of increasing the efficiency of the device. Specifically, the triplet energy (T1) of the first host (H1) H1) is the triplet energy (T1) of the second host (H2) H2 It may be equal to or smaller than ). For example, the difference between the triplet energy of the first host (H1) and the triplet energy of the second host (H2) may be 0.01 eV or less, specifically 0 eV or less. Here, the lower limit of the triplet (T1) energy of the first host and the second host is not specifically limited.

[0147] As another specific example, the singlet energy (S1 of the first host) H1 ) and the singlet energy of the second host (S1 H2 All energies can be 3.2 eV or higher.

[0148] When the first host (H1) and the second host (H2) have the aforementioned singlet (S1) energy values, the phenomenon in which singlet excitons generated in the light-emitting layer diffuse to adjacent interfaces and / or other layers, or light emission occurs at the interface, is prevented, and the singlet excitons are efficiently confined. Accordingly, the amount of excitons increases, thereby improving the luminous efficiency of the organic electroluminescent device. Specifically, the singlet energy (S1) of the first host (H1) H1 ) is the singlet energy (S1) of the second host (H2) H2 It may be equal to or higher than ). For example, the difference [Δ(S1] between the singlet energy of the first host (H1) and the singlet energy of the second host (H2). H1 - S1 H2 )] may be 0.01 eV or more. Here, the upper limit of the singlet (S1) energy of the first host and the second host is not specifically limited, respectively.

[0149] In the light-emitting layer (40) according to the present invention, the content ratio of the first host (H1) and the second host (H2) can be appropriately adjusted within a range known in the art. For example, the first host (H1) and the second host (H2) may be in a weight ratio of 2:8 to 8:2, specifically 3:7 to 7:3, more specifically 4:6 to 6:4, or 5:5.

[0150] If the first host (H1) and the second host (H2) satisfy the aforementioned HOMO energy level (HOMO), singlet (S1) energy, and triplet (T1) energy properties, the detailed composition of the compounds constituting the first host and the second host, such as the type of moiety included in the compound and its bonding location, whether a linker is introduced and its bonding location, etc., is not particularly limited.

[0151] For example, the first host may be a hole-transporting compound that does not contain an electron-transporting moiety and contains a hole-transporting moiety, and the second host may be an electron-transporting compound that contains at least one electron-transporting moiety.

[0152] In the case of using a single host in the conventional method, a charge imbalance within the light-emitting layer (40) may occur due to the inherent difference in charge mobility of the materials. In contrast, in the present invention, by using a combination of a first host (H1) with high hole mobility and a second host (H2) with high electron mobility, it is possible to improve the charge balance within the light-emitting layer (40).

[0153] Here, the electron-transporting moiety may be a conventional electron-withdrawing group (EWG) known in the art, specifically a single or polycyclic nitrogen-containing heteroaromatic ring (e.g., an azine group) containing at least one nitrogen (N). Such electron-transporting moiety (EWG) may be further specified by any one selected from the group of structural formulas below, but is not particularly limited thereto.

[0154]

[0155] In the above formula,

[0156] * indicates the part that forms a bond with the corresponding compound. Although not specifically indicated in the above structural formula, at least one substituent known in the art (e.g., identical to the definition part of R1 to R2 described below) may be substituted. Additionally, although only one part (*) connected to the compound is indicated in the above structural formula, if the electron-transporting moiety is included as a linker, cases where 2 to 3 * parts are included also fall within the scope of the present invention.

[0157] In addition, the hole transport moiety may be a conventional electron donating group (EDG) known in the field, and, for example, may mean a conventional electron donating group (EDG) moiety that is different from the aforementioned electron withdrawing group (EWG) and has higher electron donating properties than the electron withdrawing group (EWG).

[0158] For example, a compound that can be used as the first host (H1) can be represented by the following chemical formula 1.

[0159] [Chemical Formula 1]

[0160]

[0161] In the above chemical formula 1,

[0162] X1 is a single bond, or C, O, SNR 11 and CR12 R 13 It is selected from a group consisting of,

[0163] Ar1 is hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group,

[0164] R1 and R2 are identical or different from each other, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 Selected from the group consisting of arylamine groups,

[0165] R 11 to R 13 They are identical or different from one another, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group,

[0166] m, and o are identical or different from each other, and each is independently an integer from 0 to 4, and

[0167] The above Ar1, R1~R2, R 11 ~R 13 The alkyl group, alkenyl group, alkynyl group, aryl group, heteroaryl group, aryloxy group, alkyloxy group, cycloalkyl group, heterocycloalkyl group, alkylsilyl group, arylsilyl group, alkylboron group, arylboron group, arylphosphine group, arylphosphine oxide group, and arylamine group are each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C1~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other.

[0168] As a preferred embodiment of the above Chemical Formula 1, X1 is a single bond, or C, O, SNR 11 and CR 12 R 13 It is selected from a group consisting of,

[0169] Ar1 is C1~C 30 alkyl group of, C6~C 60 an aryl group, a heteroaryl group having 5 to 60 nuclei, and C6~C 60 It is selected from the group consisting of arylsilyl groups, and

[0170] R1 and R2 are identical or different from each other, and each independently C1~C 30 alkyl group of, C6~C 60 an aryl group, a heteroaryl group having 5 to 60 nuclei, and C6~C 60 It can be selected from the group consisting of arylsilyl groups, or can form a condensed ring by combining with any adjacent group,

[0171] R11 to R 13 They are identical or different from each other, and each independently hydrogen, C1~C 30 alkyl group of, C6~C 60 an aryl group, a heteroaryl group having 5 to 60 nuclei, and C6~C 60 It can be selected from the group consisting of arylsilyl groups, or can form a condensed ring by combining with any adjacent group,

[0172] m, and o are each independently integers from 0 to 4, and

[0173] The above Ar1, R1~R2, R 11 ~R 13 The alkyl group, aryl group, heteroaryl group, and arylsilyl group are each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C6~C 60 The arylsilyl group of, and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other.

[0174] The first host represented by Chemical Formula 1 described above may be further specified by compounds represented by BPH-01 to BPH-24, which are exemplified below. However, the first host of the present invention is not limited to those exemplified below.

[0175]

[0176]

[0177] As another specific example, a compound that can be used as the second host (H2) can be represented by the following chemical formula 2.

[0178] [Chemical Formula 2]

[0179]

[0180] In the above chemical formula 2,

[0181] X2 is a single bond, or C, O, SNR 21 and CR 22 R 23 It is selected from a group consisting of,

[0182] Y1 to Y3 are identical or different from each other, and each independently N or CR 24 And, at least one of Y1 to Y3 includes N,

[0183] Ar2 and Ar3 are identical or different from each other, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group,

[0184] R3 and R4 are identical or different from each other, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 Selected from the group consisting of arylamine groups,

[0185] R 21 to R 24 They are identical or different from one another, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group,

[0186] p and q are identical or different from each other, and each is independently an integer from 0 to 4, and

[0187] The above Ar2~Ar3, R3~R4, R 21 ~R 24 The alkyl group, alkenyl group, alkynyl group, aryl group, heteroaryl group, aryloxy group, alkyloxy group, cycloalkyl group, heterocycloalkyl group, alkylsilyl group, arylsilyl group, alkylboron group, arylboron group, arylphosphine group, arylphosphine oxide group, and arylamine group are each independently hydrogen, deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C1~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other.

[0188] As a preferred embodiment of the above Chemical Formula 2, X2 is a single bond, or C, O, SNR 21 and CR 22 R 23 It is selected from a group consisting of,

[0189] Y1 to Y3 are identical or different from each other, and each independently N or CR 24 And, at least one of Y1 to Y3 is N, and

[0190] Ar2 and Ar3 are identical or different from each other, and each independently C1~C 30 alkyl group of, C6~C 60 an aryl group, a heteroaryl group having 5 to 60 nuclei, and C6~C 60 It is selected from the group consisting of arylsilyl groups, and

[0191] R3 and R4 are identical or different from each other, and each independently C1~C 30 alkyl group of, C6~C 60 an aryl group, a heteroaryl group having 5 to 60 nuclei, and C6~C 60 It can be selected from the group consisting of arylsilyl groups, or can form a condensed ring by combining with any adjacent group,

[0192] R 21 to R 24 They are identical or different from each other, and each independently hydrogen, C1~C 30 alkyl group of, C6~C 60 an aryl group, a heteroaryl group having 5 to 60 nuclei, and C6~C 60 It can be selected from the group consisting of arylsilyl groups, or can form a condensed ring by combining with any adjacent group,

[0193] p and q are each independently integers from 0 to 4, and

[0194] The above Ar2~Ar3, R3~R4, R 21 ~R 24 The alkyl group, aryl group, heteroaryl group, and arylsilyl group are each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C6~C 60 The arylsilyl group of, and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other.

[0195] The second host represented by Chemical Formula 2 described above may be further embodied in compounds represented by BNH-01 to BNH-24, which are exemplified below. However, the second host of the present invention is not limited to those exemplified below.

[0196]

[0197]

[0198] The light-emitting layer (40) of the present invention comprises a first dopant (D1) and a second dopant (D2) as two or more different types of dopants. Specifically, the first dopant (D1) and the second dopant (D2) have different light emission wavelength regions centered on the maximum light emission peak, but at least a portion of these light emission wavelength regions overlap.

[0199] For example, the maximum emission wavelength (λmax) of the first dopant (D1) D1 ) is 440 nm to 490 nm, and the maximum emission wavelength (λmax) of the second dopant (D2) D2 The wavelength is 450 nm to 500 nm, wherein the emission wavelengths of the first dopant and the second dopant include an overlapping same wavelength region of 10 nm or more. For example, the long wavelength range of the first dopant (D1) and the short wavelength range of the second dopant (D2) may overlap by 10 nm or more, and specifically, the emission wavelength of the first dopant and the absorption wavelength of the second dopant overlap by 10 nm or more.

[0200] The first dopant (D1) and the second dopant (D2) may be dopants commonly used in the field. Specifically, the first dopant (D1) may be a phosphorescent dopant, and the second dopant (D2) may be a thermally activated delayed fluorescence dopant (TADF). Here, the delayed fluorescence dopant (TADF) refers to a substance that emits fluorescence (e.g., T1 -> S1 -> S0) after reverse inter-system crossing of a extinguishing triplet (T1) exciton into a singlet (S1) exciton.

[0201] Generally, holes and electrons meet to form excitons, and among the generated excitons, singlet (S1) excitons account for 25% and triplet (T1) excitons account for 75%. Singlet (S1) excitons emit light through a fluorescence phenomenon (S1 -> S0), but the fluorescence efficiency is too low. Accordingly, most organic electroluminescent devices utilize light emission through the phosphorescence phenomenon (T1 -> S0) of triplet excitons, which have high efficiency, and the internal quantum efficiency (IQE) due to this phosphorescence emission is up to about 75%.

[0202] In contrast, when a first dopant that emits phosphorescent light and a second dopant that emits fluorescent light are mixed by adjusting their physical properties to suit the present invention, 75% phosphorescent light and 25% fluorescent light can be utilized through reverse intersystem transition, thereby increasing the internal quantum efficiency of the device to 100% and significantly improving the efficiency characteristics of the device.

[0203] In the light-emitting layer (40) according to the present invention, the first dopant (D1) may be included in an amount of 15 weight% or less based on 100 weight% of the light-emitting layer, specifically 13 weight% or less, and more specifically 12 weight% or less. In addition, the second dopant (D2) may be included in an amount of 4 weight% or less based on 100 weight% of the light-emitting layer, specifically 3.5 weight% or less, and more specifically 3 weight% or less. At this time, the lower limit of the content of the first dopant and the second dopant is not particularly limited and may, for example, exceed 0 weight%.

[0204] In addition, the content ratio of the first dopant (D1) and the second dopant (D2) can be appropriately adjusted within a range known in the art. For example, the first dopant (D1) and the second dopant (D2) may be in a weight ratio of 9.5:0.5 to 7:3, and specifically, in a weight ratio of 9:1 to 7.5:2.5.

[0205] If the above-mentioned first dopant (D1) and second dopant (D2) satisfy the physical properties of the maximum emission wavelength (λmax) and the overlapping wavelength range thereof, the detailed composition of the compounds constituting the first dopant and the second dopant, such as the type of moiety included in the compound and its bonding location, whether a linker is introduced and its bonding location, etc., is not particularly limited.

[0206] For example, the first dopant (D1) is a phosphorescent dopant containing a metal (M), such as platinum (Pt). Specifically, the first dopant may be an organic complex containing platinum (Pt). The metal may be a transition metal capable of forming polydentate chemical bonds with an organic material (e.g., a ligand), including platinum. In this case, the chemical bonds include conventional bonds known in the art, and may be, for example, at least one of covalent bonds and coordinate bonds.

[0207] For example, a compound that can be used as the first dopant (D1) can be represented by the following chemical formula 3.

[0208] [Chemical Formula 3]

[0209]

[0210] In the above chemical formula 3,

[0211] M is a metal atom capable of two covalent bonds and two coordinate bonds, which is platinum (Pt), and

[0212] R5 to R7 are identical or different from one another, and each independently has a single bond, O, S, C2~C 30 alkylene group of, C6~C 18 Selected from the group consisting of an arylene group and a heteroarylene group having 5 to 18 nuclei,

[0213] B, C, D, and E are identical or different from one another, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 Selected from the group consisting of arylamine groups,

[0214] However, at least one of B, C, D and E comprises a moiety represented by the following chemical formula 3A, and

[0215] [Chemical Formula 3A]

[0216]

[0217] In the above chemical formula 3A,

[0218] * indicates the position where it combines with M,

[0219] r can be an integer from 0 to 4, and

[0220] R8 is hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It may be selected from the group consisting of arylamines or may form a condensation ring by combining with any adjacent group, wherein if r is 2 or more, multiple R8s are identical or different from each other,

[0221] Ar4 and Ar5 are identical or different from each other, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring with any one selected from adjacent B, C, D, and E, and

[0222] G is C6~C 60 aryl group of, C6~C 60 It is selected from the group consisting of an arylene group and a heteroarylene group having 5 to 60 nuclei, wherein when r is 2 or more, multiple Gs are identical or different from each other,

[0223] B, C, D, and E of Formula 3 above, and the alkyl groups of R8, Ar4~Ar5, alkenyl, alkynyl, aryl, heteroaryl, aryloxy, alkyloxy, cycloalkyl, heterocycloalkyl, alkylsilyl, arylsilyl, alkylboron, arylboron, arylphosphine, arylphosphine oxide, and arylamine groups of Formula 3A above; and the aryl group, arylene group, and heteroarylene group of G of Formula 3A above; each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C1~C40 alkyloxy group of, C6~C 60 The aryloxy group of, C1~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other.

[0224] In a preferred embodiment of the above Chemical Formula 3 and Chemical Formula 3A, M is platinum, and

[0225] R5 to R7 are each independently a single bond or O, and

[0226] B, C, D, and E are each independently C6~C 60 an aryl group, a heteroaryl group having 5 to 60 nuclei, and C6~C 60 Selected from the group consisting of arylsilyl groups, provided that at least one of B, C, D and E comprises a moiety represented by 3A below,

[0227] R8 is C1~C 30 alkyl group of, C6~C 60 an aryl group, a heteroaryl group having 5 to 60 nuclei, and C6~C 60 It can be selected from the group consisting of arylsilyl groups, or can form a condensed ring by combining with any adjacent group,

[0228] Ar4 and Ar5 can each independently form a condensation ring with any one selected from adjacent B, C, D, and E, provided that if Chemical Formula 3A is B or E, C1~C 30 alkyl group of, C6~C 60 an aryl group, a heteroaryl group having 5 to 60 nuclei, and C6~C60 It can be selected from the group consisting of arylsilyl groups, or can form a condensed ring by combining with any adjacent group,

[0229] G is C6~C 60 aryl group of, C6~C 60 It can be selected from the group consisting of an arylene group and a heteroarylene group having 5 to 60 nuclei, wherein when r is 2 or more, multiple Gs are identical or different from each other,

[0230] B, C, D, and E of Formula 3 above, and the alkyl groups R8, Ar4~Ar5, aryl groups, heteroaryl groups, and arylsilyl groups of Formula 3A above; and the aryl group, arylene group, and heteroarylene group of G of Formula 3A above; each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C6~C 60 The arylsilyl group of, and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other.

[0231] The first dopant (D1) represented by Chemical Formula 3 described above may be further specified by compounds represented by PTB-01 to PTB-10, which are exemplified below. However, the first dopant of the present invention is not limited to those exemplified below.

[0232]

[0233] In addition, the second dopant (D2) may be a fluorescent dopant containing boron (B), specifically having an absorption wavelength that overlaps with the emission wavelength of the first dopant by more than 10 nm.

[0234] For example, a compound that can be used as the second dopant (D2) can be represented by the following chemical formula 4.

[0235] [Chemical Formula 4]

[0236]

[0237] In the above chemical formula 4,

[0238] R9 to R 11 , Ar6 and Ar7 are identical or different from each other, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group,

[0239] s, and t are integers from 0 to 4, respectively, and

[0240] u is an integer from 0 to 3, and

[0241] The above R9~R 11, in Ar6~Ar7, alkyl groups, alkenyl groups, alkynyl groups, aryl groups, heteroaryl groups, aryloxy groups, alkyloxy groups, cycloalkyl groups, heterocycloalkyl groups, alkylsilyl groups, arylsilyl groups, alkylboron groups, arylboron groups, arylphosphine groups, arylphosphine oxide groups, and arylamine groups are; each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C1~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other.

[0242] A preferred embodiment of the above Chemical Formula 4 is R9 to R 11 , Ar6 and Ar7 are identical or different from each other, and each independently C1~C 30 alkyl group of, C6~C 60 an aryl group, a heteroaryl group having 5 to 60 nuclei, and C6~C 60 It can be selected from the group consisting of arylsilyl groups, or combined with any adjacent group to form a condensed ring.

[0243] If s is 0, R9 is hydrogen, and if s is not 0, it may have the aforementioned substituents excluding hydrogen without restriction. The same applies to t and u. Specifically, s, t and u may each be integers from 0 to 2.

[0244] The above R9~R 11 , in Ar6~Ar7, the alkyl group, aryl group, heteroaryl group, and arylsilyl group are each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C6~C 60 The arylsilyl group of, and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other.

[0245] The second dopant (D2) represented by Chemical Formula 4 described above may be further embodied in compounds represented by BD-01 to BD-10 as exemplified below. However, the second dopant of the present invention is not limited to those exemplified below.

[0246]

[0247] The light-emitting layer (40) according to the present invention is composed of the first host (H1), the second host (H2), the first dopant (D1), and the second dopant (D2) described above. At this time, the mixing ratio of these can be appropriately adjusted within a range known in the art. For example, the content ratio of the total host and the total dopant in the light-emitting layer (40) may be a weight ratio of 70:30 to 99.5:0.5, specifically a weight ratio of 75:25 to 97:3, and more specifically a weight ratio of 80:20 to 95:5.

[0248] The aforementioned light-emitting layer (40) may be a single layer composed of multiple different hosts and dopants, or a plurality of layers comprising two or more layers. For example, when the light-emitting layer consists of multiple layers, the organic electroluminescent device can emit light of various colors. Additionally, when multiple light-emitting layers are included, the driving voltage of the device increases, while the current value within the organic electroluminescent device becomes constant, thereby providing an organic electroluminescent device with improved light-emitting efficiency corresponding to the number of light-emitting layers.

[0249] The light-emitting layer (40) can be manufactured using conventional methods known in the art. Examples include vacuum deposition, spin coating, casting, LB method (Langmuir-Blodgett), inkjet printing, laser printing, and laser induced thermal imaging (LITI), but are not limited thereto.

[0250] In addition, the thickness of the light-emitting layer (40) can be appropriately adjusted within a conventional range known in the art, for example, about 100 Å to about 500 Å. When the thickness of the light-emitting layer (40) satisfies the range described above, excellent light-emitting characteristics can be exhibited.

[0251] Meanwhile, although not shown in the drawing, the organic electroluminescent device (100) may have a plurality of light-emitting stacks (not shown) including at least one light-emitting layer.

[0252] A plurality of light-emitting layers included in such a light-emitting stack may each be light-emitting layers that emit light of different colors or light-emitting layers that emit light of the same color. That is, the color of light emitted may vary depending on the material constituting the light-emitting layer. For example, a plurality of light-emitting stacks may include materials that emit blue, green, red, yellow, white, etc., and may be formed using phosphorescent or fluorescent materials. In this case, the colors exhibited by each light-emitting layer may be complementary colors to one another. Additionally, colors may be selected as a combination of colors capable of emitting white light. Each of these light-emitting layers may each include phosphorescent dopants or fluorescent dopants corresponding to the selected color.

[0253] For example, at least one of the plurality of light-emitting layers may include the aforementioned first host, second host, first dopant, and second dopant.

[0254] Additionally, although not shown in the drawing, the organic electroluminescent device (100) may further include a charge generation layer (not shown) that is disposed between adjacent stacks among a plurality of light-emitting stacks and connects them.

[0255] A charge generation layer (CGL) refers to a layer that separates adjacent light-emitting stacks without directly contacting both electrodes (e.g., anode, cathode) in an organic light-emitting device having multiple light-emitting stacks. This charge generation layer is positioned between two adjacent light-emitting stacks to generate electrons for one light-emitting stack and act as a cathode, and generates holes for the other light-emitting stack and acts as an anode. The charge generation layer may be formed using any material known in the art that can be used as a charge generation layer material without limitation. Additionally, the material used for the charge generation layer may be formed by doping it with a conventional n-type material and / or p-type material known in the art.

[0256] Electron transport auxiliary layer

[0257] The organic electroluminescent device according to the present invention includes an electron transport auxiliary layer (53) disposed between the light-emitting layer (40) and the electron transport region (50).

[0258] This electron transport auxiliary layer (53) serves to more efficiently transport electrons from the electron transport region (50), specifically the electron transport layer (52), to the light-emitting layer (40), while simultaneously trapping excitons generated within the light-emitting layer (40) and preventing excess holes within the light-emitting layer (40) from being transported to the electron transport region (50), such as the electron transport layer (52). Accordingly, the present invention not only increases the light-emitting efficiency in the light-emitting layer (40) but also prevents hole leakage from the light-emitting layer (40) to the electron transport region (50), thereby improving the lifespan characteristics of the device.

[0259] In particular, the electron transport auxiliary layer (53) according to the present invention is differentiated from conventional organic electroluminescent devices in that it not only has physical properties such as a predetermined HOMO energy (HOMO), LUMO energy (LUMO), and triplet (T1) energy, but also organically and precisely controls to have an appropriate energy gap compared to the light-emitting layer (40) and electron transport layer (52) that include all of the aforementioned multiple types of hosts and multiple types of dopants.

[0260] For example, the electron transport auxiliary layer (53) may satisfy the following formulas (v) to (vii).

[0261] (v) HOMO aETL ≥ 5.5 eV

[0262] (vi) LUMO aETL ≤ 2.0 eV

[0263] (vii) T1 aETL ≥ 2.8 eV

[0264] In the above equation, HOMO aETL, LUMO aETL and T1 aETL are the absolute values ​​of the HOMO energy levels, LUMO energy levels, and triplet energies of the electron transport auxiliary layer material calculated according to the Gaussian, respectively.

[0265] The electron transport auxiliary layer (53) has the aforementioned HOMO energy level (HOMO aETL If the value is ), the phenomenon in which holes delivered to the light-emitting layer (40) diffuse or cross over to the electron transport region (50), such as the electron transport layer (52), can be blocked. Accordingly, the probability of recombination where holes and electrons meet inside the light-emitting layer (40) can be increased, thereby further increasing the luminous efficiency of the organic electroluminescent device. In addition, the lifespan characteristics of the device can be improved by resolving the irreversible decomposition reaction caused by oxidation resulting from holes diffusing or moving beyond the light-emitting layer (40) to the electron transport layer (52), and the resulting degradation of the lifespan of the organic electroluminescent device. Specifically, the absolute value of the HOMO energy level of the electron transport auxiliary layer (53) (HOMO aETL ) can be 5.51 eV or higher. Here, the upper limit of the HOMO energy of the electron transport auxiliary layer (53) is not specifically limited.

[0266] The electron moves along the LUMO energy level. The electron transport layer (53) follows the aforementioned LUMO energy level (LUMO aETL If the value is ), electrons transferred from the electron transport region (50) can move smoothly to the light-emitting layer (40), thereby increasing the efficiency of the organic electroluminescent device. Specifically, the absolute value of the LUMO energy level of the electron transport auxiliary layer (53) (LUMO aETL ) is 1.97 eV or less, and more specifically, may be 1.95 eV or less. Here, the absolute lower limit of the LUMO energy level of the electron transport auxiliary layer (53) is not specifically limited.

[0267] In addition, if the electron transport assist layer (53) has the aforementioned triplet (T1) energy value, it prevents excitons in the light-emitting layer (40) from moving to other layers, thereby enabling the effect of significantly increasing the efficiency of the organic electroluminescent device. Specifically, the triplet (T1) energy of the electron transport assist layer (53) may be 2.81 eV or higher. Here, the upper limit of the triplet (T1) energy of the electron transport assist layer (53) is not particularly limited.

[0268] As another specific example, the first host (H1) and the electron transport auxiliary layer (53) included in the light-emitting layer (40) may satisfy the following equation (viii).

[0269] (viii) HOMO aETL - HOMO H1 ≥ 0.3 eV

[0270] In the above equation, HOMO aETL silver It is the absolute value of the HOMO energy levels of the electron transport auxiliary layer material calculated according to the Gaussian, and HOMO H1 is the absolute value of the HOMO energy level of the first host material calculated according to the Gaussian.

[0271] When the difference between the absolute value of the HOMO energy level of the electron transport assist layer (53) and the absolute value of the HOMO energy level of the first host (H1) has the aforementioned range, the HOMO of the electron transport assist layer (53) is formed deeply, thereby preventing excess holes in the light-emitting layer from moving to the electron transport layer (Hole Block), and at the same time, it can have sufficient electrical properties to efficiently confine excitons within the light-emitting layer. Specifically, the absolute value of the HOMO energy level of the electron transport assist layer (HOMO aETL The absolute value of the HOMO energy level of the first host (H1) included in the ) and the light-emitting layer (40) (HOMO H1 The difference of ) can be greater than 0.32 eV.

[0272] As another specific example, the first host (H1) and the electron transport auxiliary layer (53) included in the light-emitting layer (40) may satisfy the following formula (ix).

[0273] (ix) LUMO aETL - LUMO H1 ≥ 0.3 eV

[0274] In the above equation, LUMO aETL silver It is the absolute value of the LUMO energy levels of the electron transport auxiliary layer material calculated according to the Gaussian, and LUMO H1 is the absolute value of the LUMO energy level of the first host material calculated according to the Gaussian.

[0275] When the difference between the absolute value of the LUMO energy level of the electron transport assist layer (53) and the absolute value of the LUMO energy level of the first host (H1) has the aforementioned range, the LUMO energy level of the first host (H1) is sufficiently high, so that electrons transmitted from the electron transport assist layer (53) are not transmitted to the first host (H1) but are smoothly transmitted to the second host (H2), and at the same time, the efficiency and lifespan characteristics of the device can be simultaneously improved by preventing electrons from escaping the light-emitting layer (40) and flowing into the hole transport region (30). Specifically, the absolute value of the LUMO energy level of the electron transport assist layer (53) (LUMO aETL The absolute value of the LUMO energy level of the first host (H1) included in the ) and the light-emitting layer (40) (LUMO H1 The difference of ) can be greater than 0.5 eV.

[0276] As another specific example, the second host (H2) and the electron transport auxiliary layer (53) included in the light-emitting layer (40) may satisfy the following equation (x).

[0277] (x) LUMO aETL - LUMO H2 ≤ 0.2 eV

[0278] In the above equation, LUMOaETL Is It is the absolute value of the LUMO energy level of the electron transport auxiliary layer material calculated according to the Gaussian formula, and LUMO H2 is the absolute value of the LUMO energy level of the second host material calculated according to the Gaussian.

[0279] When the difference between the absolute value of the LUMO energy level of the electron transport assist layer (53) and the absolute value of the LUMO energy level of the second host (H2) has the aforementioned range, since the LUMO energy level of the second host (H2) is lower than that of the electron transport assist layer (53), electron transfer from the electron transport region (50) to the light-emitting layer (40) is facilitated, thereby producing an advantageous effect in the driving voltage characteristics of the device. Specifically, the absolute value of the LUMO energy level (LUMO) of the electron transport assist layer (53) aETL The absolute value of the LUMO energy level of the second host (H2) included in the ) and the light-emitting layer (40) (LUMO H2 The difference of ) is 0.20 eV or less, and more specifically, may be 0.19 eV or less. This can be determined as an energy level value that facilitates the transfer of electrons from one layer to another while sufficiently increasing the electron density at the interface between the electron transport assist layer (53) and the light-emitting layer (40).

[0280] The electron transport auxiliary layer (53) according to the present invention is the aforementioned HOMO energy (HOMO aETL ), LUMO Energy (LUMO aETL ), triplet (T1 aETL If the physical properties such as energy and the appropriate energy gap properties relative to the host included in the light-emitting layer (40) are satisfied, the detailed composition of the compound constituting the electron transport auxiliary layer (53), such as the type of moiety included in the compound and its bonding location, whether a linker is introduced and its bonding location, etc., is not particularly limited.

[0281] For example, the electron transport auxiliary layer (53) may include an electron transport compound that is different from the second host (H2) and includes at least one conventional electron transport moiety known in the art.

[0282] For example, the electron transport auxiliary layer (53) may include a compound represented by the following chemical formula 5.

[0283] [Chemical Formula 5]

[0284]

[0285] In the above chemical formula 5,

[0286] Y4 to Y6 are identical or different from each other, and each independently N or CR 31 However, at least one of Y4 to Y6 is N, and

[0287] R 12 , R 31 , Ar8 and Ar9 are identical or different from each other, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group,

[0288] v is an integer from 1 to 4, and

[0289] L is a single bond, or C6~C 18 Selected from the group consisting of an arylene group and a heteroarylene group having 5 to 18 nuclei,

[0290] A is C, Si, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group,

[0291] The arylene group and heteroarylene group of the above L, and the above R 12 , R 31 , the alkyl groups, alkenyl groups, alkynyl groups, aryl groups, heteroaryl groups, aryloxy groups, alkyloxy groups, cycloalkyl groups, heterocycloalkyl groups, alkylsilyl groups, arylsilyl groups, alkylboron groups, arylboron groups, arylphosphine groups, arylphosphine oxide groups, and arylamine groups of Ar8~Ar9 and A are each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C1~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other.

[0292] In a preferred embodiment of the above Chemical Formula 5, Y4 to Y6 are identical or different from each other, and each independently N or CR 31 However, at least one of Y4 to Y6 is N, and

[0293] R 12 , R 31 , Ar8 and Ar9 are identical or different from each other, and each independently C1~C 30 alkyl group of, C6~C 60 an aryl group, a heteroaryl group having 5 to 60 nuclei, and C6~C 60 It can be selected from the group consisting of arylsilyl groups, or can form a condensed ring by combining with any adjacent group,

[0294] L is a single bond, or C6~C 18 Selected from the group consisting of an arylene group and a heteroarylene group having 5 to 18 nuclei,

[0295] A is C, Si, C6~C 60 an aryl group, a heteroaryl group having 5 to 60 nuclei, and C6~C 60It can be selected from the group consisting of arylsilyl groups, or can form a condensation ring by combining with any adjacent group, and specifically can be selected from C, Si, benzene, naphthalene, dibenzofuran, etc.

[0296] v is an integer from 1 to 4, wherein v is 4 when A is C or Si, and v is an integer from 1 to 3 when A is a substituent other than C and Si.

[0297] The arylene group and heteroarylene group of the above L, and the above R 12 , R 31 , the alkyl, aryl, heteroaryl, and arylsilyl groups of Ar8~Ar9 and A are each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C6~C 60 The arylsilyl group of, and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other.

[0298] The compound constituting the electron transport assist layer (53) represented by Chemical Formula 5 described above may be further specified as the compounds represented by ETA-1 to ETA-24 exemplified below. However, the electron transport assist layer material of the present invention is not limited to those exemplified below.

[0299]

[0300]

[0301] The electron transport auxiliary layer (53) can be manufactured using conventional methods known in the art. Examples include vacuum deposition, spin coating, casting, LB method (Langmuir-Blodgett), inkjet printing, laser printing, and laser induced thermal imaging (LITI), but are not limited thereto.

[0302] In addition, the thickness of the electron transport auxiliary layer (53) can be appropriately adjusted within a normal range known in the field, for example, about 50 Å to about 200 Å. When the thickness of the electron transport auxiliary layer (53) satisfies the range described above, not only is the light emission efficiency of the light-emitting layer increased, but hole leakage from the light-emitting layer to the electron transport region is prevented, thereby ensuring an increase in the efficiency and lifespan characteristics of the device.

[0303] Meanwhile, in the present invention, the electron transport auxiliary layer (53) is described as a separate layer, but this is described as an example for convenience, and in a broader sense, it can be understood as being included in a part of the electron transport region (50) described later.

[0304] Electronic transport area

[0305] In the organic electroluminescent device (100) according to the present invention, the electron transport region (50) included in the organic layer (A) serves to move electrons injected from the second electrode (20) to the light-emitting layer (40).

[0306] This electron transport region (50) has an electron transport layer (52) positioned adjacent to the electron transport auxiliary layer (53), and may include an electron injection layer (51) as needed. Considering the characteristics of the organic electroluminescent device, it is preferable to include the electron transport layer (52) and the electron injection layer (51).

[0307] The electron transport layer (52) according to the present invention is characterized in that its physical properties, such as HOMO energy (HOMO), LUMO energy (LUMO), and triplet (T1) energy, are controlled to be within a predetermined range, and also have an appropriate energy gap property compared to the adjacent electron transport auxiliary layer (53).

[0308] For example, the electron transport auxiliary layer (aETL, 53) and the electron transport layer (ETL, 52) may satisfy the conditions of the following equation (xi).

[0309] (xi) 0 ≤ LUMO ETL - LUMO aETL ≤ 0.2 eV

[0310] In the above equation, LUMO ETL is the absolute value of the LUMO energy level of the electron transport layer material calculated according to the Gaussian, and LUMO aETL is the absolute value of the LUMO energy level of the electron transport auxiliary layer material calculated according to the Gaussian.

[0311] Electrons in the electron transport layer (52) move along the LUMO energy levels. However, if the difference between the absolute value of the LUMO energy level of the electron transport layer (52) and the absolute value of the LUMO energy level of the electron transport auxiliary layer (53) is large, an electron injection barrier is formed between these interfaces, making it difficult for electrons to be transferred smoothly, which causes a problem of increasing the driving voltage of the device. Accordingly, in the present invention, the difference in LUMO energy levels between the electron transport auxiliary layer (53) and the electron transport layer (52) is adjusted so that it does not exceed the aforementioned range, thereby allowing a sufficient amount of electrons to be transferred smoothly from the electron transport layer (52) to the electron transport auxiliary layer (53). Specifically, the absolute value of the LUMO energy level of the electron transport layer (52) (LUMO ETL ) and the absolute value of the LUMO energy level of the electron transport auxiliary layer (52) (LUMO aETLThe difference of ) is 0 to 0.19 eV, and more specifically, may be 0 to 0.18 eV.

[0312] As another specific example, the electron transport layer (52) may satisfy the conditions of the following formulas (xii) to (xiv).

[0313] (xii) HOMO ETL ≥ 5.7 eV

[0314] (xiii) LUMO ETL ≤ 2.1 eV

[0315] (xiv) T1 ETL ≥2.8 eV

[0316] In the above equation, HOMO ETL , LUMO ETL and T1 ETL ε₀ is the absolute value of the HOMO energy level, the absolute value of the LUMO energy level, and the triplet energy of the electron transport layer material calculated according to the Gaussian, respectively.

[0317] Specifically, electrons in the electron transport layer (52) move along LUMO energy levels, and this electron transport layer (52) is the absolute value of the aforementioned LUMO energy level (LUMO ETL If the value is ), electrons delivered from the electron injection layer (51) can move smoothly to the electron transport assist layer (53), thereby increasing the efficiency of the organic electroluminescent device. Specifically, the absolute value of the LUMO energy level of the electron transport layer (52) (LUMO ETL ) is 2.1 eV or less, and more specifically, may be 2.05 eV or less. Here, the absolute lower limit of the LUMO energy level of the electron transport layer (52) is not specifically limited.

[0318] In addition, the electron transport layer (52) has the absolute value of the aforementioned HOMO energy level (HOMO ETLIf the value is ), the irreversible decomposition reaction caused by oxidation resulting from holes diffusing or moving beyond the light-emitting layer (40) to the electron transport layer (52) and the resulting degradation of the lifespan of the organic electroluminescent device can be resolved, thereby improving the lifespan characteristics of the device. Specifically, the absolute value of the HOMO energy level of the electron transport layer (5) (HOMO ETL ) is 5.71 eV or higher, and more specifically, may be 5.71 to 6.1 eV. Here, the upper limit of the absolute value of the HOMO energy level of the electron transport layer (52) is not particularly limited.

[0319] In addition, if the electron transport layer (52) has the aforementioned triplet (T1) energy value, it prevents excitons in the light-emitting layer (40) from moving to other layers, thereby enabling the effect of significantly increasing the efficiency of the organic electroluminescent device. Specifically, the triplet (T1) of the electron transport layer (52) ETL The energy can be 2.81 eV or higher. Here, the upper limit of the triplet (T1) energy of the electron transport layer (52) is not specifically limited.

[0320] The electron transport layer (52) according to the present invention is the aforementioned HOMO energy (HOMO ETL ), LUMO Energy (LUMO ETL ), triplet energy (T1 ETL If the physical properties such as ) and the appropriate energy gap properties relative to the electron transport auxiliary layer (53) are satisfied, the detailed composition of the compound constituting the electron transport layer (52), such as the type of moiety included in the compound and its bonding location, whether a linker is introduced and its bonding location, etc., is not particularly limited.

[0321] For example, the electron transport layer (52) may be different from the electron transport auxiliary layer (53) material and may include an electron transport compound comprising at least one conventional electron transport moiety known in the art.

[0322] For example, the electron transport layer (52) may include a compound represented by the following chemical formula 6.

[0323] [Chemical Formula 6]

[0324]

[0325] In the above chemical formula 6,

[0326] A plurality of Zs are identical or different from one another, and each is independently CR or N, provided that at least one of the plurality of Zs is N,

[0327] Ar 10 or Ar 14 They are identical or different from each other, and each independently hydrogen, deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 arylphosphine oxide group, C6~C 60 The arylamine group of, C5~C 60 It can be selected from the group consisting of an aryl heteroarylamine group and a heteroarylamine group having 5 to 60 nuclei, or can form a condensation ring by combining with any adjacent group;

[0328] M is C, Si, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group,

[0329] R, R 13 to R 14 They are identical or different from each other, and each independently hydrogen, deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 arylphosphine oxide group, C6~C 60 The arylamine group of, C5~C 60It can be selected from the group consisting of an aryl heteroarylamine group and a heteroarylamine group having 5 to 60 nuclei, or can form a condensation ring by combining with any adjacent group;

[0330] w is an integer from 1 to 4, provided that if M is C or Si, w is 1, and

[0331] N is a monocyclic or polycyclic hydrocarbon ring containing one or more heteroatoms, and

[0332] L1 and L2 are identical or different from each other, and each is independently a single bond or C6~C 18 Selected from the group consisting of an arylene group and a heteroarylene group having 5 to 18 nuclei,

[0333] In the above chemical formula 6, the arylene groups of L1 to L2, the heteroarylene group; and Ar 10 ~Ar 14 , R, R 13 ~R 14 , and the alkyl group, alkenyl group, alkynyl group, cycloalkyl group, heterocycloalkyl group, aryl group, heteroaryl group, alkyloxy group, aryloxy group, alkylsilyl group, arylsilyl group, alkylboron group, arylboron group, arylphosphine group, arylphosphine oxide group, arylamine group of M, and the hydrocarbon ring of N are each independently hydrogen, deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C1~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C60 arylphosphine group of, C6~C 60 arylphosphine oxide group, C6~C 60 The arylamine group of, C5~C 60 It may be substituted with one or more substituents selected from the group consisting of an aryl heteroarylamine group and a heteroarylamine group having 5 to 60 nuclei, and in the case where there are multiple substituents, they may be identical or different from each other.

[0334] In a preferred embodiment of the above chemical formula 6, a plurality of Zs include 2 to 3 Ns, and

[0335] Ar 10 or Ar 14 are identical or different from each other, and each independently C1~C 30 alkyl group of, C6~C 30 aryl groups, heteroaryl groups with 5 to 30 nuclei, and C6~C 30 It can be selected from the group consisting of arylsilyl groups, or can form a condensed ring by combining with any adjacent group,

[0336] M can be selected from C, Si, benzene, naphthalene, and dibenzofuran, and

[0337] R, R 13 to R 14 are identical or different from each other, and each independently C1~C 30 alkyl group of, C6~C 30 aryl groups, heteroaryl groups with 5 to 30 nuclei, and C6~C 30 It can be selected from the group consisting of arylsilyl groups, or can form a condensed ring by combining with any adjacent group,

[0338] w is an integer from 1 to 4, wherein w is 1 when M is C or Si, and w is an integer from 1 to 3 when M is any one of the aforementioned substituents excluding C and Si, such as benzene, naphthalene, and dibenzofuran.

[0339] N is a nitrogen-containing heterocyclic ring with at least two Ns, either monocyclic or polycyclic, and may be identical to or different from the aforementioned plurality of Z-containing rings.

[0340] In the above chemical formula 6, the arylene groups of L1 to L2, the heteroarylene group; and Ar 10 ~Ar 14 , R, R 13 ~R 14 , and the alkyl group, alkenyl group, alkynyl group, cycloalkyl group, heterocycloalkyl group, aryl group, heteroaryl group, alkyloxy group, aryloxy group, alkylsilyl group, arylsilyl group, alkylboron group, arylboron group, arylphosphine group, arylphosphine oxide group, arylamine group of M, and the hydrocarbon ring of N are each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C6~C 60 The arylsilyl group of, and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other.

[0341] The compound constituting the electron transport layer (52) represented by Chemical Formula 6 described above may be further specified as the compounds represented by ETL-1 to ETL-20 exemplified below. However, the electron transport layer (52) material of the present invention is not limited to those exemplified below.

[0342]

[0343]

[0344] The electron transport region (50) according to the present invention may have an electron injection layer (51).

[0345] This electron injection layer (51) may be used in which an n-type dopant is co-deposited to facilitate the injection of electrons from the cathode (20). In this case, the n-type dopant may be any alkali metal complex known in the art without limitation, such as alkali metals, alkaline earth metals, or rare earth metals.

[0346] The aforementioned electron transport region (50) can be manufactured through conventional methods known in the art. Examples include vacuum deposition, spin coating, casting, LB method (Langmuir-Blodgett), inkjet printing, laser printing, and laser induced thermal imaging (LITI), but are not limited thereto.

[0347] Meanwhile, the electron transport region (50) may be composed of an electron transport layer (52) and an electron transport auxiliary layer (53), and the total thickness may be 150 Å to 600 Å. At this time, the thickness of the electron transport layer (52) may be about 100 Å to 400 Å, and the thickness of the electron transport auxiliary layer (53) may be about 50 Å to about 200 Å as described above. If the electron transport region (50) satisfies the thickness range described above, satisfactory electron transport characteristics can be obtained without a substantial increase in driving voltage. In addition, the electron transport region (50) may include an electron injection layer (51), and the thickness of such electron injection layer (51) may be appropriately adjusted within a conventional range known in the art, for example, about 5 Å to about 100 Å.

[0348] light-emitting auxiliary layer

[0349] The organic light-emitting element (100) of the present invention may further include a light-emitting auxiliary layer (not shown) disposed between the hole transport region (30) and the light-emitting layer (40).

[0350] The light-emitting auxiliary layer serves to transport holes moving from the hole transport region (30) to the light-emitting layer (30) and to control the thickness of the organic layer (A). This light-emitting auxiliary layer has a high LUMO value to prevent electrons from moving to the hole transport layer and has a high triplet energy to prevent excitons from the light-emitting layer from diffusing into the hole transport layer.

[0351] This light-emitting auxiliary layer may include a hole transport material and may be made of the same material as the hole transport region. Additionally, the light-emitting auxiliary layers of red, green, and blue organic light-emitting devices may be made of the same material.

[0352] The material for the light-emitting auxiliary layer is not particularly limited, and examples include carbazole derivatives or arylamine derivatives. Non-limiting examples of usable light-emitting auxiliary layers include NPD (N, N-dinaphthyl-N, N'-diphenyl benzidine), TPD (N, N'-bis-(3-methylphenyl)-N, N'-bis(phenyl)-benzidine), s-TAD, and MTDATA (4, 4', 4″-Tris(N-3-methylphenyl-Nphenyl-amino)-triphenylamine). These may be used alone or in a mixture of two or more. In addition, the light-emitting auxiliary layer may include a p-type dopant in addition to the aforementioned materials. Known p-type dopants used in the relevant art may be used as such p-type dopants.

[0353] capping layer

[0354] The organic electroluminescent device (100) according to the present invention may further include a capping layer (not shown) disposed on the second electrode (20). This capping layer protects the organic electroluminescent device and helps light generated from the organic layer (A) to be efficiently emitted to the outside.

[0355] The capping layer may comprise at least one selected from the group consisting of tris-8-hydroxyquinoline aluminum (Alq3), ZnSe, 2,5-bis(6′- (2′,2″-bipyridyl))-1,1-dimethyl-3,4-diphenylsilole, 4′-bis[N-(1-napthyl)-N-phenyl-amion] biphenyl (α-NPD), N,N′-diphenyl-N,N′-bis(3-methylphenyl)-1,1′-biphenyl-4,4′-diamine (TPD), and 1,1′-bis(di-4-tolylaminophenyl) cyclohexane (TAPC).

[0356] The capping layer may be a single layer, or may include two or more layers having different refractive indices, so that the refractive index changes gradually as it passes through two or more layers.

[0357] The above capping layer can be manufactured through conventional methods known in the art, and various methods such as vacuum deposition, spin coating, casting, or the Langmuir-Blodgett (LB) method can be used.

[0358] The organic electroluminescent device (100) of the present invention, comprising the above-described configuration, can be manufactured according to conventional methods known in the art. For example, an organic light-emitting device can be manufactured by vacuum depositing an anode material on a substrate, and then vacuum depositing materials of a hole transport region material, a light-emitting layer material, an electron transport auxiliary layer material, an electron transport region material, and a cathode material in sequence on the anode.

[0359] In addition, the organic electroluminescent device (100) according to the present invention has a structure in which a first electrode (10), an organic layer (A), and a second electrode (20) are sequentially stacked, and may further include a conventional insulating layer or adhesive layer known in the art between the first electrode (10) and the organic layer (A) or between the second electrode (20) and the organic layer (A). The organic electroluminescent device of the present invention may have excellent lifespan characteristics because, when voltage, current, or both are applied, the lifespan of the initial brightness is increased while maintaining maximum luminous efficiency.

[0360]

[0361] The present invention will be described in detail below through examples, but the following examples are merely illustrative of the invention and the invention is not limited by the following examples.

[0362]

[0363] <1st Host Synthesis>

[0364] [Synthesization Example 1] Synthesis of BPH-01

[0365]

[0366] 9-([1,1'-biphenyl]-3-yl)-9H,9'H-3,3'-bicarbazole (4.84 g, 10 mmol), (3-bromophenyl)triphenylsilane (4.15 g, 10 mmol), Pd(OAc)2 (0.22 g, 1 mmol), P(t-Bu)3 (0.47 ml, 2 mmol), NaO(t-Bu) (1.92 g, 20 mmol), and 100 ml of toluene were mixed under a nitrogen stream and stirred at 110°C for 3 hours. After the reaction was complete, the toluene was concentrated, the solid salt was filtered, and the target compound BPH-01 (3.76 g, yield 46%) was obtained using column chromatography.

[0367] Mass : [(M+H) + ] : 819

[0368]

[0369] [Synthesization Example 2] Synthesis of BPH-02

[0370]

[0371] 9-phenyl-9H,9'H-3,3'-bicarbazole (4.08 g, 10 mmol), (3-bromophenyl)triphenylsilane (4.15 g, 10 mmol), Pd(OAc)2 (0.22 g, 1 mmol), P(t-Bu)3 (0.47 ml, 2 mmol), NaO(t-Bu) (1.92 g, 20 mmol), and 100 ml of toluene were mixed under a nitrogen stream and stirred at 110°C for 3 hours. After the reaction was complete, the toluene was concentrated, the solid salt was filtered, and the target compound BPH-02 (3.49 g, yield 47%) was obtained using column chromatography.

[0372] Mass : [(M+H) + ] : 743

[0373]

[0374] [Synthesization Example 3] Synthesis of BPH-03

[0375]

[0376] 4-(9H-carbazol-3-yl)-N,N-diphenylaniline (4.10 g, 10 mmol), (3-bromophenyl)triphenylsilane (4.15 g, 10 mmol), Pd(OAc)2 (0.22 g, 1 mmol), P(t-Bu)3 (0.47 ml, 2 mmol), NaO(t-Bu) (1.92 g, 20 mmol), and 100 ml of toluene were mixed under a nitrogen stream and stirred at 110°C for 3 hours. After the reaction was complete, the toluene was concentrated, the solid salt was filtered, and the target compound BPH-03 (3.65 g, yield 49%) was obtained using column chromatography.

[0377] Mass : [(M+H) + ] : 745

[0378]

[0379] [Synthesization Example 4] Synthesis of BPH-04

[0380]

[0381] 3'-phenyl-9H-3,9'-bicarbazole (4.08 g, 10 mmol), (3-bromophenyl)trimethylsilane (2.29 g, 10 mmol), Pd(OAc)2 (0.22 g, 1 mmol), P(t-Bu)3 (0.47 ml, 2 mmol), NaO(t-Bu) (1.92 g, 20 mmol), and 100 ml of toluene were mixed under a nitrogen stream and stirred at 110°C for 3 hours. After the reaction was complete, the toluene was concentrated, the solid salt was filtered, and the target compound BPH-04 (2.33 g, yield 42%) was obtained using column chromatography.

[0382] Mass : [(M+H) + ] : 556

[0383]

[0384] [Synthesization Example 5] Synthesis of BPH-05

[0385]

[0386] (3,5-di(9H-carbazol-9-yl)phenyl)boronic acid (4.52 g, 10 mmol), (3-bromophenyl)trimethylsilane (2.29 g, 10 mmol), Pd(PPh3)4 (0.34 g, 0.3 mmol), and K2CO3 (2.76 g, 20 mmol) were added to 100 ml of 1,4-Dioxane and 25 ml of H2O, and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound BPH-05 (3.06 g, yield 55%) was obtained by column chromatography.

[0387] Mass : [(M+H) + ] : 556

[0388]

[0389] [Synthesization Example 6] Synthesis of BPH-06

[0390] 9-(3-bromophenyl)-9H-carbazole (3.22 g, 10 mmol) was dissolved in excess THF, the temperature was lowered to -78°C, and 2.5 M n-BuLi (1 eq) was added dropwise to obtain Reactant-1. 9-(3-bromophenyl)-3-phenyl-9H-carbazole (3.98 g, 10 mmol) was dissolved in excess THF in another flask, the temperature was lowered to -78°C, and 2.5 M n-BuLi (1 eq) was added dropwise and stirred for 3 hours, after which dichlorodiphenylsilane (2.53 g, 10 mmol) was added to obtain Reactant-2. The previously produced Reactant-1 was added dropwise to the resulting Reactant-2, the mixture was slowly heated to room temperature, and stirred for 10 hours. After the reaction was completed, water was added and the solvent of the organic layer was removed by extraction, and the target compound BPH-06 (2.45 g, yield 33%) was obtained using silica column chromatography.

[0391] Mass : [(M+H) + ] : 743

[0392]

[0393] [Synthesization Example 7] Synthesis of BPH-07

[0394]

[0395] 3-bromo-9-(3-(triphenylsilyl)phenyl)-9H-carbazole (5.80 g, 10 mmol), (7-(naphthalen-2-yl)-7H-benzo[c]carbazol-10-yl)boronic acid (3.87 g, 10 mmol), Pd(PPh3)4 (0.34 g, 0.3 mmol), and K2CO3 (2.76 g, 20 mmol) were added to 100 ml of 1,4-Dioxane and 25 ml of H2O, and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound BPH-07 (4.29 g, yield 51%) was obtained by column chromatography.

[0396] Mass : [(M+H) + ] : 843

[0397]

[0398] [Synthesization Example 8] Synthesis of BPH-08

[0399]

[0400] (3-bromophenyl)triphenylsilane (4.15 g, 10 mmol), 5-phenyl-5,7-dihydroindolo[2,3-b]carbazole (3.32 g, 10 mmol), Pd(OAc)2 (0.22 g, 1 mmol), P(t-Bu)3 (0.47 ml, 2 mmol), NaO(t-Bu) (1.92 g, 20 mmol), and 100 ml of toluene were mixed under a nitrogen stream and stirred at 110°C for 3 hours. After the reaction was complete, the toluene was concentrated, the solid salt was filtered, and the target compound BPH-08 (3.20 g, yield 48%) was obtained using column chromatography.

[0401] Mass : [(M+H) + ] : 666

[0402]

[0403] [Synthesization Example 9] Synthesis of BPH-09

[0404]

[0405] (3-bromophenyl)triphenylsilane (4.15 g, 10 mmol), 5-(naphthalen-2-yl)-5,7-dihydroindolo[2,3-b]carbazole (3.82 g, 10 mmol), Pd(OAc)2 (0.22 g, 1 mmol), P(t-Bu)3 (0.47 ml, 2 mmol), NaO(t-Bu) (1.92 g, 20 mmol), and 100 ml of toluene were mixed under a nitrogen stream and stirred at 110°C for 3 hours. After the reaction was complete, the toluene was concentrated, the solid salt was filtered, and the target compound BPH-09 (3.22 g, yield 45%) was obtained using column chromatography.

[0406] Mass : [(M+H) + ] : 716

[0407]

[0408] [Synthesization Example 10] Synthesis of BPH-10

[0409]

[0410] (3-bromophenyl)triphenylsilane (4.15 g, 10 mmol), 7-phenyl-7H,7'H-10,10'-bibenzo[c]carbazole (5.08 g, 10 mmol), Pd(OAc)2 (0.22 g, 1 mmol), P(t-Bu)3 (0.47 ml, 2 mmol), NaO(t-Bu) (1.92 g, 20 mmol), and 100 ml of toluene were mixed under a nitrogen stream and stirred at 110°C for 3 hours. After the reaction was complete, the toluene was concentrated, the solid salt was filtered, and the target compound BPH-10 (3.54 g, yield 42%) was obtained using column chromatography.

[0411] Mass : [(M+H) + ] : 843

[0412]

[0413] [Synthesization Example 11] Synthesis of BPH-11

[0414]

[0415] (3-bromophenyl)di(naphthalen-2-yl)(phenyl)silane (5.15 g, 10 mmol), 9-phenyl-9H,9'H-3,3'-bicarbazole (4.08 g, 10 mmol), Pd(OAc)2 (0.22 g, 1 mmol), P(t-Bu)3 (0.47 ml, 2 mmol), NaO(t-Bu) (1.92 g, 20 mmol), and 100 ml of toluene were mixed under a nitrogen stream and stirred at 110°C for 3 hours. After the reaction was complete, the toluene was concentrated, the solid salt was filtered, and the target compound BPH-11 (3.37 g, yield 40%) was obtained using column chromatography.

[0416] Mass : [(M+H) + ] : 843

[0417]

[0418] [Synthesization Example 12] Synthesis of BPH-12

[0419] <Step 1> Synthesis of (3-bromophenyl)tri(naphthalen-2-yl)silane

[0420]

[0421] 1,3-dibromobenzene (2.35 g, 10 mmol) was dissolved in excess THF, the temperature was lowered to -78°C, and 2.5 M n-BuLi (1 eq) was added dropwise to obtain Reactant-1. 2-bromonaphthalene (2.07 g, 10 mmol) was dissolved in excess THF in another flask, the temperature was lowered to -78°C, and 2.5 M n-BuLi (1 eq) was added dropwise and stirred for 3 hours, after which dichlorodi(naphthalen-2-yl)silane (3.53 g, 10 mmol) was added to obtain Reactant-2. The previously produced Reactant-1 was added dropwise to the resulting Reactant-2, the mixture was slowly heated to room temperature, and stirred for 10 hours. After the reaction was completed, water was added and the solvent of the organic layer was removed by extraction, and the target compound (3-bromophenyl)tri(naphthalen-2-yl)silane (2.09 g, yield 37%) was obtained using silica column chromatography.

[0422] Mass : [(M+H) + ] : 565

[0423] <Step 2> Synthesis of BPH-12

[0424]

[0425] (3-bromophenyl)di(naphthalen-2-yl)(phenyl)silane (5.65 g, 10 mmol), N-(4-(9H-carbazol-3-yl)phenyl)-N-phenylnaphthalen-1-amine (4.60 g, 10 mmol), Pd(OAc)2 (0.22 g, 1 mmol), P(t-Bu)3 (0.47 ml, 2 mmol), NaO(t-Bu) (1.92 g, 20 mmol), and 100 ml of toluene were mixed under a nitrogen stream and stirred at 110°C for 3 hours. After the reaction was complete, the toluene was concentrated, the solid salt was filtered, and the target compound BPH-12 (4.15 g, yield 44%) was obtained using column chromatography.

[0426] Mass : [(M+H) + ] : 945

[0427]

[0428] <2nd Host Synthesis>

[0429] [Synthesization Example 13] Synthesis of BNH-01

[0430]

[0431] 9-(4,6-dichloro-1,3,5-triazin-2-yl)-9H-carbazole (3.15 g, 10 mmol), (3-(triphenylsilyl)phenyl)boronic acid (7.60 g, 20 mmol), Pd(PPh3)4 (0.34 g, 0.3 mmol), and K2CO3 (2.76 g, 20 mmol) were added to 100 ml of 1,4-Dioxane and 25 ml of H2O, and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound BNH-01 (3.75 g, yield 41%) was obtained by column chromatography.

[0432] Mass : [(M+H) +] : 915

[0433]

[0434] [Synthesization Example 14] Synthesis of BNH-02

[0435]

[0436] 10-(4,6-dichloro-1,3,5-triazin-2-yl)-10H-phenoxazine (3.31 g, 10 mmol), (3-(triphenylsilyl)phenyl)boronic acid (7.60 g, 20 mmol), Pd(PPh3)4 (0.34 g, 0.3 mmol), and K2CO3 (2.76 g, 20 mmol) were added to 100 ml of 1,4-Dioxane and 25 ml of H2O, and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound BNH-O2 (3.72 g, yield 40%) was obtained by column chromatography.

[0437] Mass : [(M+H) + ] : 931

[0438]

[0439] [Synthesization Example 15] Synthesis of BNH-03

[0440] <Step 1> Synthesis of (2'-nitro-[1,1'-biphenyl]-2-yl)triphenylsilane

[0441]

[0442] triphenyl(2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)silane (4.62 g, 10 mmol), 1-bromo-2-nitrobenzene (2.02 g, 10 mmol), Pd(PPh3)4 (0.34 g, 0.3 mmol), and K2CO3 (2.76 g, 20 mmol) were added to 100 ml of 1,4-Dioxane and 25 ml of H2O and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, the compound (2'-nitro-[1,1'-biphenyl]-2-yl)triphenylsilane (2.33 g, yield 51%) was obtained by column chromatography.

[0443] Mass : [(M+H) + ] : 457

[0444] <Step 2> Synthesis of 4-(triphenylsilyl)-9H-carbazole

[0445]

[0446] (2'-nitro-[1,1'-biphenyl]-2-yl)triphenylsilane (4.57 g, 10 mmol) and PPh3 (6.55 g, 25 mmol) were added to 50 ml of 1,2-Dichlorobenzene and stirred at 150°C for 18 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound 4-(triphenylsilyl)-9H-carbazole (1.83 g, yield 43%) was obtained using column chromatography.

[0447] Mass : [(M+H) + ] : 425

[0448] <Step 3> Synthesis of BNH-03

[0449]

[0450] 4-(triphenylsilyl)-9H-carbazole (4.25 g, 10 mmol), 2-chloro-4-phenyl-6-(3-(triphenylsilyl)phenyl)-1,3,5-triazine (5.26 g, 10 mmol), Pd(OAc)2 (0.22 g, 1 mmol), P(t-Bu)3 (0.47 ml, 2 mmol), NaO(t-Bu) (1.92 g, 20 mmol), and 100 ml of toluene were mixed under a nitrogen stream and stirred at 110°C for 3 hours. After the reaction was complete, the toluene was concentrated, the solid salt was filtered, and the target compound BNH-03 (4.48 g, yield 49%) was obtained using column chromatography.

[0451] [Mass]: 915

[0452]

[0453] [Synthesization Example 16] Synthesis of BNH-04

[0454]

[0455] 9-(2,6-dichloropyrimidin-4-yl)-9H-carbazole (3.14 g, 10 mmol), (3-(triphenylsilyl)phenyl)boronic acid (7.60 g, 20 mmol), Pd(PPh3)4 (0.34 g, 0.3 mmol), and K2CO3 (2.76 g, 20 mmol) were added to 100 ml of 1,4-Dioxane and 25 ml of H2O, and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound BNH-04 (4.02 g, yield 44%) was obtained by column chromatography.

[0456] Mass : [(M+H) + ] : 914

[0457]

[0458] [Synthesization Example 17] Synthesis of BNH-05

[0459]

[0460] (3-(9H-carbazol-9-yl)phenyl)boronic acid (2.87 g, 10 mmol), 2-chloro-4-phenyl-6-(3-(triphenylsilyl)phenyl)-1,3,5-triazine (5.26 g, 10 mmol), Pd(PPh3)4 (0.34 g, 0.3 mmol), and K2CO3 (2.76 g, 20 mmol) were added to 100 ml of 1,4-dioxane and 25 ml of H2O and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound BNH-05 (3.81 g, yield 52%) was obtained by column chromatography.

[0461] Mass : [(M+H) + ] : 732

[0462]

[0463] [Synthesization Example 18] Synthesis of BNH-06

[0464]

[0465] 9-(4-([1,1'-biphenyl]-3-yl)-6-chloro-1,3,5-triazin-2-yl)-9H-carbazole (4.32 g, 10 mmol), (3-(triphenylsilyl)phenyl)boronic acid (3.80 g, 10 mmol), Pd(PPh3)4 (0.34 g, 0.3 mmol), and K2CO3 (2.76 g, 20 mmol) were added to 100 ml of 1,4-Dioxane and 25 ml of H2O and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound BNH-06 (4.03 g, yield 55%) was obtained by column chromatography.

[0466] Mass : [(M+H) + ] : 732

[0467]

[0468] [Synthesization Example 19] Synthesis of BNH-07

[0469]

[0470] 9-(4-chloro-6-(phenanthren-9-yl)-1,3,5-triazin-2-yl)-9H-carbazole (4.56 g, 10 mmol), (3-(triphenylsilyl)phenyl)boronic acid (3.80 g, 10 mmol), Pd(PPh3)4 (0.34 g, 0.3 mmol), and K2CO3 (2.76 g, 20 mmol) were added to 100 ml of 1,4-Dioxane and 25 ml of H2O, and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound BNH-07 (3.93 g, yield 52%) was obtained by column chromatography.

[0471] Mass : [(M+H) + ] : 756

[0472]

[0473] [Synthesization Example 20] Synthesis of BNH-08

[0474] <Step 1> Synthesis of 2-chloro-4-(naphthalen-2-yl)-6-(3-(triphenylsilyl)phenyl)-1,3,5-triazine

[0475]

[0476] 2,4-dichloro-6-(naphthalen-2-yl)-1,3,5-triazine (5.52 g, 20 mmol), (3-(triphenylsilyl)phenyl)boronic acid (3.80 g, 10 mmol), PdCl2(PPh3)2 (0.14 g, 0.2 mmol), and K2CO3 (2.76 g, 20 mmol) were added to 100 ml of toluene and 25 ml of H2O, and stirred at 100°C for 12 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, the compound 2-chloro-4-(naphthalen-2-yl)-6-(3-(triphenylsilyl)phenyl)-1,3,5-triazine (2.76 g, yield 48%) was obtained using column chromatography.

[0477] Mass : [(M+H) + ] : 576

[0478] <Step 2> Synthesis of BNH-08

[0479]

[0480] 2-chloro-4-(naphthalen-2-yl)-6-(3-(triphenylsilyl)phenyl)-1,3,5-triazine (5.76 g, 10 mmol), 5H-benzo[b]carbazole (2.17 g, 10 mmol), Pd(OAc)2 (0.22 g, 1 mmol), P(t-Bu)3 (0.47 ml, 2 mmol), NaO(t-Bu) (1.92 g, 20 mmol), and 100 ml of toluene were mixed under a nitrogen stream and stirred at 110°C for 3 hours. After the reaction was complete, the toluene was concentrated, the solid salt was filtered, and the target compound BNH-08 (3.33 g, yield 44%) was obtained using column chromatography.

[0481] [Mass]: 756

[0482]

[0483] [Synthesization Example 21] Synthesis of BNH-09

[0484]

[0485] 2-chloro-4-phenyl-6-(3-(triphenylsilyl)phenyl)-1,3,5-triazine (5.26 g, 10 mmol), 6H-dibenzo[b,h]carbazole (2.67 g, 10 mmol), Pd(OAc)2 (0.22 g, 1 mmol), P(t-Bu)3 (0.47 ml, 2 mmol), NaO(t-Bu) (1.92 g, 20 mmol), and 100 ml of toluene were mixed under a nitrogen stream and stirred at 110°C for 3 hours. After the reaction was complete, the toluene was concentrated, the solid salt was filtered, and the target compound BNH-09 (2.95 g, yield 39%) was obtained using column chromatography.

[0486] [Mass]: 756

[0487]

[0488] [Synthesization Example 22] Synthesis of BNH-10

[0489] <Step 1> Synthesis of (3-bromophenyl)di(naphthalen-2-yl)(phenyl)silane

[0490]

[0491] 1,3-dibromobenzene (2.35 g, 10 mmol) was dissolved in excess THF, the temperature was lowered to -78°C, and 2.5 M n-BuLi (1 eq) was added dropwise to obtain Reactant-1. Bromobenzene (1.57 g, 10 mmol) was dissolved in excess THF in another flask, the temperature was lowered to -78°C, and 2.5 M n-BuLi (1 eq) was added dropwise and stirred for 3 hours, after which dichlorodi(naphthalen-2-yl)silane (3.53 g, 10 mmol) was added to obtain Reactant-2. The previously produced Reactant-1 was added dropwise to the resulting Reactant-2, the mixture was slowly heated to room temperature, and stirred for 10 hours. After the reaction was completed, water was added and the solvent of the organic layer was removed by extraction, and the target compound (3-bromophenyl)di(naphthalen-2-yl)(phenyl)silane (1.80 g, yield 35%) was obtained using silica column chromatography.

[0492] Mass : [(M+H) + ] : 515

[0493] <Step 2> Synthesis of di(naphthalen-2-yl)(phenyl)(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)silane

[0494]

[0495] (3-bromophenyl)di(naphthalen-2-yl)(phenyl)silane (5.15 g, 10 mmol), 4,4,4',4',5,5,5',5'-octamethyl-2,2'-bi(1,3,2-dioxaborolane) (3.80 g, 15 mmol), Pd(dppf)Cl2 (0.36 g, 0.5 mmol), and KOAc (1.96 g, 20 mmol) were added to 100 ml of 1,4-Dioxane and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, the compound di(naphthalen-2-yl)(phenyl)(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)silane (2.86 g, yield 51%) was obtained using column chromatography.

[0496] Mass : [(M+H) + ] : 562

[0497] <Step 3> Synthesis of 2-chloro-4-(3-(di(naphthalen-2-yl)(phenyl)silyl)phenyl)-6-(naphthalen-1-yl)-1,3,5-triazine

[0498]

[0499] di(naphthalen-2-yl)(phenyl)(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)silane (5.52 g, 10 mmol), 2,4-dichloro-6-(naphthalen-1-yl)-1,3,5-triazine (5.52 g, 20 mmol), PdCl2(PPh3)2 (0.14 g, 0.2 mmol), and K2CO3 (2.76 g, 20 mmol) were added to 100 ml of toluene and 25 ml of H2O and stirred at 100°C for 12 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, the compound 2-chloro-4-(3-(di(naphthalen-2-yl)(phenyl)silyl)phenyl)-6-(naphthalen-1-yl)-1,3,5-triazine (2.09 g, yield 31%) was obtained using column chromatography.

[0500] Mass : [(M+H) + ] : 676

[0501] <Step 4> Synthesis of BNH-10

[0502]

[0503] 2-chloro-4-(3-(di(naphthalen-2-yl)(phenyl)silyl)phenyl)-6-(naphthalen-1-yl)-1,3,5-triazine (6.76 g, 10 mmol), (4-(9H-carbazol-9-yl)naphthalen-1-yl)boronic acid (3.37 g, 10 mmol), Pd(PPh3)4 (0.34 g, 0.3 mmol), and K2CO3 (2.76 g, 20 mmol) were added to 100 ml of 1,4-dioxane and 25 ml of H2O and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, the compound BNH-10 (5.03 g, yield 54%) was obtained by column chromatography.

[0504] Mass : [(M+H) + ] : 933

[0505]

[0506] <Synthesis of the 1st Dopant>

[0507] [Synthesization Example 23 Synthesis of PTB-05]

[0508] <Step 1> Synthesis of 3-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)aniline

[0509]

[0510] Under a nitrogen stream, 2-bromo-9-(pyridin-2-yl)-9H-carbazole (32.3 g, 100.0 mmol), 3-aminophenol (13.1 g, 120.0 mmol), CuI (1.9 g, 10.0 mmol), L-proline (2.3 g, 20.0 mmol), and Cs2CO3 (65.2 g, 200.0 mmol) were added to 200 mL of DMSO and stirred at 120°C for 72 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, ethyl acetate was added, and the organic layer was separated and extracted. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography to obtain compound 3-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)aniline (25.5 g, 72.6 mmol, yield 73%).

[0511] Mass [(M+H) + ] : 352

[0512] <Step 2> N 1 -phenyl-N 2 -Synthesis of (3-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)phenyl)benzene-1,2-diamine

[0513]

[0514] Under a nitrogen stream, 2-bromo-N-phenylaniline (16.4 g, 66.1 mmol), 3-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)aniline (25.5 g, 72.6 mmol), Pd(OAc)2 (815 mg, 3.6 mmol), CyJohnPhos (2.5 g, 7.3 mmol), and t-BuONa (10.5 g, 108.9 mmol) were added to 360 mL of toluene and heated and stirred under reflux for 18 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and ethyl acetate was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography to obtain compound N 1 -phenyl-N 2 -(3-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)phenyl)benzene-1,2-diamine (29.5 g, 56.9 mmol, yield 78%) was obtained.

[0515] Mass [(M+H) + ] : 519

[0516] <Step 3> Synthesis of PTB-05

[0517]

[0518] N under a nitrogen stream 1 -phenyl-N 2-(3-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)phenyl)benzene-1,2-diamine (29.5 g, 56.9 mmol) and NH4PF6 (10.2 g, 62.6 mmol) were added to 115 mL of triethyl orthoformate and stirred at 120°C for 12 hours. After the reaction was complete, ethyl acetate was added and stirred at room temperature. The precipitated solid was filtered to obtain 3-phenyl-1-(3-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)phenyl)-1H-benzo[d]imidazol-3-ium hexafluorophosphate (22.3 g, 33.0 mmol). Subsequently, 3-phenyl-1-(3-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)phenyl)-1H-benzo[d]imidazol-3-ium hexafluorophosphate (22.3 g, 33.0 mmol), Pt(COD)Cl2 (11.2 g, 30.0 mmol), and NaOAc (2.8 g, 34.7 mmol) were added to 66 mL of THF under a nitrogen stream and heated and refluxed for 68 hours. After the reaction was complete, the mixture was concentrated and then purified by column chromatography packed with silica gel to obtain compound PTB-05 (7.9 g, 10.9 mmol, yield 19%).

[0519] Mass [(M+H) + ] : 722

[0520]

[0521] [Synthesization Example 24 Synthesis of PTB-06]

[0522] <Step 1> Synthesis of [Pt2(μ-Cl)2(ppb)2]

[0523]

[0524] N under a nitrogen stream 1 ,N 2-diphenylbenzene-1,2-diamine (26.0 g, 100.0 mmol) and NH4BF4 (10.5 g, 100.0 mmol) were added to 300 mL of triethyl orthoformate and stirred at 120°C for 18 hours. After the reaction was complete, the mixture was stirred at room temperature, and the precipitated solid was filtered and washed with triethyl orthoformate and petroleum ether to obtain 1,3-diphenyl-1H-benzo[d]imidazol-3-ium tetrafluoroborate (29.9 g, 83.6 mmol). Subsequently, under a nitrogen stream, 1,3-diphenyl-1H-benzo[d]imidazol-3-ium tetrafluoroborate (29.9 g, 83.6 mmol) was added to 3.1 L of DCM, Ag2O (9.7 g, 41.8 mmol) was added, and the mixture was stirred at room temperature for 3 hours. Next, [{Pt(ㅅ-Cl)(η 3 22.9 g, 40.1 mmol of 2-2-Me-Cl(3H4)}2] was added and stirred at room temperature for 3 hours. The reaction mixture was filtered through celite, and after concentrating the solution, 850 mL of 2-methoxyethanol was added and heated under reflux stirring for 3 hours. After the reaction was complete, the mixture was stirred at room temperature to filter the precipitated solid, which was then washed with diethyl ether to obtain the compound [Pt2(μ-Cl)2(ppb)2] (21.6 g, 21.6 mmol, yield 43%).

[0525] Mass [(M+H) + ] : 999

[0526] <Step 2> Synthesis of PTB-06

[0527]

[0528] [Pt2(μ-Cl)2(ppb)2] (21.6 g, 21.6 mmol) and 9-(pyridin-2-yl)-9H-carbazole (13.2 g, 54.0 mmol) were added to 45 mL of 2-methoxyethanol and heated under reflux stirring for 24 hours. After the reaction was complete, the mixture was stirred at room temperature to precipitate the solid. The precipitated solid was filtered, washed with diethyl ether, and purified by column chromatography packed with silica gel to obtain compound PTB-06 (xx g, xx mmol, yield xx%).

[0529] Mass [(M+H) + ] : 708

[0530]

[0531] [Synthesization Example 25 Synthesis of PTB-07]

[0532] <Step 1> Synthesis of 3-(tert-butyl)-5-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)aniline

[0533]

[0534] Under a nitrogen stream, 2-bromo-9-(pyridin-2-yl)-9H-carbazole (32.3 g, 100.0 mmol), 3-amino-5-(tert-butyl)phenol (19.8 g, 120.0 mmol), CuI (1.9 g, 10.0 mmol), L-proline (2.3 g, 20.0 mmol), and Cs2CO3 (65.2 g, 200.0 mmol) were added to 200 mL of DMSO and stirred at 120°C for 72 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, ethyl acetate was added, and the organic layer was separated and extracted. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography to obtain the compound 3-(tert-butyl)-5-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)aniline (30.3 g, 74.3 mmol, yield 73%).

[0535] Mass [(M+H) + ] : 408

[0536] <Step 2> N 1 -(3-(tert-butyl)-5-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)phenyl)-N 2 Synthesis of -phenylbenzene-1,2-diamine

[0537]

[0538] Under a nitrogen stream, 2-bromo-N-phenylaniline (16.8 g, 67.6 mmol), 3-(tert-butyl)-5-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)aniline (30.3 g, 74.3 mmol), Pd(OAc)2 (834 mg, 3.7 mmol), CyJohnPhos (2.6 g, 7.4 mmol), and t-BuONa (10.7 g, 111.5 mmol) were added to 370 mL of toluene and heated and stirred under reflux for 18 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and ethyl acetate was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography to obtain compound N 1 -(3-(tert-butyl)-5-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)phenyl)-N 2 -phenylbenzene-1,2-diamine (32.6 g, 56.8 mmol, yield 76%) was obtained.

[0539] Mass [(M+H) + ] : 575

[0540] <Step 3> Synthesis of PTB-07

[0541]

[0542] N under a nitrogen stream 1 -(3-(tert-butyl)-5-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)phenyl)-N 2-phenylbenzene-1,2-diamine (32.6 g, 56.8 mmol) and NH4PF6 (10.2 g, 62.4 mmol) were added to 110 mL of triethyl orthoformate and stirred at 120°C for 12 hours. After the reaction was complete, ethyl acetate was added and stirred at room temperature. The precipitated solid was filtered to obtain 1-(3-(tert-butyl)-5-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)phenyl)-3-phenyl-1H-benzo[d]imidazol-3-ium hexafluorophosphate (25.0 g, 34.2 mmol). Subsequently, 1-(3-(tert-butyl)-5-((9-(pyridin-2-yl)-9H-carbazol-2-yl)oxy)phenyl)-3-phenyl-1H-benzo[d]imidazol-3-ium hexafluorophosphate (25.0 g, 34.2 mmol), Pt(COD)Cl2 (11.6 g, 31.1 mmol), and NaOAc (2.9 g, 35.9 mmol) were added to 70 mL of THF under a nitrogen stream and heated and refluxed for 65 hours. After the reaction was complete, the mixture was concentrated and then purified by column chromatography packed with silica gel to obtain compound PTB-07 (9.4 g, 12.1 mmol, yield 21%).

[0543] Mass [(M+H) + ] : 778

[0544]

[0545] [Synthesization Example 26 Synthesis of PTB-08]

[0546] <Step 1> Synthesis of 6-((9-phenyl-9H-carbazol-2-yl)oxy)pyridin-2-amine

[0547]

[0548] Under a nitrogen stream, 2-bromo-9-phenyl-9H-carbazole (32.3 g, 100.0 mmol), 6-aminopyridin-2-ol (13.2 g, 120.0 mmol), CuI (1.9 g, 10.0 mmol), L-proline (2.3 g, 20.0 mmol), and Cs2CO3 (65.2 g, 200.0 mmol) were added to 200 mL of DMSO and stirred at 120°C for 72 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, ethyl acetate was added, and the organic layer was separated and extracted. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography to obtain compound 6-((9-phenyl-9H-carbazol-2-yl)oxy)pyridin-2-amine (22.0 g, 62.6 mmol, yield 63%).

[0549] Mass [(M+H) + ] : 352

[0550] <Step 2> N 1 -phenyl-N 2 -Synthesis of (6-((9-phenyl-9H-carbazol-2-yl)oxy)pyridin-2-yl)benzene-1,2-diamine

[0551]

[0552] Under a nitrogen stream, 2-bromo-N-phenylaniline (14.1 g, 57.0 mmol), 6-((9-phenyl-9H-carbazol-2-yl)oxy)pyridin-2-amine (22.0 g, 62.6 mmol), Pd(OAc)2 (703 mg, 3.1 mmol), CyJohnPhos (2.2 g, 6.3 mmol), and t-BuONa (9.0 g, 93.9 mmol) were added to 315 mL of toluene and heated and stirred under reflux for 18 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and ethyl acetate was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography to obtain compound N 1 -phenyl-N 2 -(6-((9-phenyl-9H-carbazol-2-yl)oxy)pyridin-2-yl)benzene-1,2-diamine (25.8 g, 49.7 mmol, yield 79%) was obtained.

[0553] Mass [(M+H) + ] : 519

[0554] <Step 3> Synthesis of PTB-08

[0555]

[0556] N under a nitrogen stream 1 -phenyl-N 2-(6-((9-phenyl-9H-carbazol-2-yl)oxy)pyridin-2-yl)benzene-1,2-diamine (25.8 g, 49.7 mmol) and NH4PF6 (8.9 g, 54.7 mmol 1.1 eq) were added to 100 mL of triethyl orthoformate and stirred at 120°C for 12 hours. After the reaction was complete, ethyl acetate was added and stirred at room temperature. The precipitated solid was filtered to obtain 3-phenyl-1-(6-((9-phenyl-9H-carbazol-2-yl)oxy)pyridin-2-yl)-1H-benzo[d]imidazol-3-ium hexafluorophosphate (22.1 g, 32.7 mmol). Subsequently, 3-phenyl-1-(6-((9-phenyl-9H-carbazol-2-yl)oxy)pyridin-2-yl)-1H-benzo[d]imidazol-3-ium hexafluorophosphate (22.1 g, 32.7 mmol), Pt(COD)Cl2 (11.1 g, 29.8 mmol), and NaOAc (2.8 g, 34.3 mmol) were added to 65 mL of THF under a nitrogen stream and heated and refluxed for 70 hours. After the reaction was complete, the mixture was concentrated and then purified by column chromatography packed with silica gel to obtain compound PTB-08 (6.2 g, 8.7 mmol, yield 17%).

[0557] Mass [(M+H) + ] : 722

[0558]

[0559] Synthesis of the 2nd Dopant

[0560] [Synthesized Example 27] Synthesis of BD-05

[0561] <Step 1> N 1 ,N 3 -bis(3-(tert-butyl)phenyl)-2-chloro-N 1 ,N 3Synthesis of -diphenylbenzene-1,3-diamine

[0562]

[0563] Under a nitrogen stream, 1-Bromo-2,3-dichlorobenzene (22.6 g, 100 mmol), 3-(tert-butyl)-N-phenylaniline (49.6 g, 220.0 mmol), (AMPHOS)2PdCl2 (779 mg, 1.1 mmol), and t-BuONa (24.0 g, 250.0 mmol) were added to 225 mL of o-xylene and stirred at 80°C for 2 hours and at 120°C for 3 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and ethyl acetate was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. The solid obtained after concentration and stirring with a small amount of toluene and hexane was filtered to obtain compound N 1 ,N 3 -bis(3-(tert-butyl)phenyl)-2-chloro-N 1 ,N 3 -diphenylbenzene-1,3-diamine (36.6 g, 65.4 mmol, yield 65%) was obtained.

[0564] Mass [(M+H) + ] : 559

[0565] <Step 2> Synthesis of BD-05

[0566]

[0567] N under a nitrogen stream 1 ,N 3 -bis(3-(tert-butyl)phenyl)-2-chloro-N 1 ,N 336.6 g, 65.4 mmol of diphenylbenzene-1,3-diamine was added to 220 mL of tert-butylbenzene, and tert-butyllithium (46.2 mL, 78.5 mmol, 1.70 M sol. in pentane) was slowly added at -30°C and stirred at 60°C for 3 hours. Next, the mixture was concentrated to remove pentane, cooled to -30°C, and then BBr3 (7.6 mL, 78.5 mmol) was slowly added. The reaction mixture was stirred at room temperature for 30 minutes, cooled to 0°C, and then N,N-Diisopropylethylamine (22.8 mL, 130.8 mmol) was added. Next, the mixture was stirred at 120°C for 2 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, ethyl acetate was added, and the organic layer was separated and extracted. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. After concentration, the solid obtained by stirring with a small amount of toluene and hexane was filtered to obtain the compound 3,11-di-tert-butyl-5,9-diphenyl-5,9-dihydro-5,9-diaza-13b-boranaphtho[3,2,1-de]anthracene (9.9 g, 18.6 mmol, yield 28%).

[0568] Mass [(M+H) + ] : 533

[0569]

[0570] [Synthesized Example 28] Synthesis of BD-06

[0571] <Step 1> Synthesis of 2,3-dichloro-N-(m-tolyl)-N-(p-tolyl)aniline

[0572]

[0573] Under a nitrogen stream, 1-Bromo-2,3-dichlorobenzene (22.6 g, 100 mmol), 3-methyl-N-(p-tolyl)aniline (19.7 g, 100.0 mmol), (AMPHOS)2PdCl2 (354 mg, 0.5 mmol), and t-BuONa (14.4 g, 150.0 mmol) were added to 225 mL of o-xylene and stirred at 90°C for 3 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and ethyl acetate was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. After concentration, the solid obtained by stirring with a small amount of toluene and hexane was filtered to obtain the compound 2,3-dichloro-N-(m-tolyl)-N-(p-tolyl)aniline (26.6 g, 77.6 mmol, yield 78%).

[0574] Mass [(M+H) + ] : 342

[0575] <Step 2> N 1 -(4-(9H-carbazol-9-yl)phenyl)-2-chloro-N 1 -phenyl-N 3 -(m-tolyl)-N 3 Synthesis of -(p-tolyl)benzene-1,3-diamine

[0576]

[0577] Under a nitrogen stream, 2,3-dichloro-N-(m-tolyl)-N-(p-tolyl)aniline (26.6 g, 77.6 mmol), 4-(9H-carbazol-9-yl)-N-phenylaniline (26.0 g, 77.6 mmol), (AMPHOS)2PdCl2 (604 mg, 0.9 mmol), and t-BuONa (11.2 g, 116.4 mmol) were added to 175 mL of o-xylene and stirred at 120°C for 2 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and ethyl acetate was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. The solid obtained after concentration and stirring in small amounts of toluene and hexane was filtered to obtain compound N 1 -(4-(9H-carbazol-9-yl)phenyl)-2-chloro-N 1 -phenyl-N 3 -(m-tolyl)-N 3 -(p-tolyl)benzene-1,3-diamine (40.4 g, 63.2 mmol, yield 81%) was obtained.

[0578] Mass [(M+H) + ] : 640

[0579] <Step 3> Synthesis of BD-06

[0580]

[0581] N under a nitrogen stream 1 -(4-(9H-carbazol-9-yl)phenyl)-2-chloro-N 1 -phenyl-N 3 -(m-tolyl)-N 3-(p-tolyl)benzene-1,3-diamine (40.4 g, 63.2 mmol) was added to 420 mL of tert-butylbenzene, and tert-butyllithium (44.6 mL, 75.8 mmol, 1.70 M sol. in pentane) was slowly added at -30°C and stirred at 60°C for 3 hours. Next, the mixture was concentrated to remove pentane, cooled to -30°C, and BBr3 (7.3 mL, 75.8 mmol) was slowly added. The reaction mixture was stirred at room temperature for 30 minutes, cooled to 0°C, and then N,N-Diisopropylethylamine (22.0 mL, 126.3 mmol) was added. Next, the mixture was stirred at 120°C for 2 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, ethyl acetate was added, and the organic layer was separated and extracted. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. After concentration, the solid obtained by stirring with a small amount of toluene and hexane was filtered to obtain the compound 9-(4-(9H-carbazol-9-yl)phenyl)-3-methyl-5-(p-tolyl)-5,9-dihydro-5,9-diaza-13b-boranaphtho[3,2,1-de]anthracene (11.4 g, 18.6 mmol, yield 29%).

[0582] Mass [(M+H) + ] : 614

[0583]

[0584] [Synthesized Example 29] Synthesis of BD-07

[0585] <Step 1> N 1 ,N 3 -bis(4-(tert-butyl)phenyl)-2-chloro-N 1 ,N 3 Synthesis of -diphenylbenzene-1,3-diamine

[0586]

[0587] Under a nitrogen stream, 1-Bromo-2,3-dichlorobenzene (22.6 g, 100 mmol), 4-(tert-butyl)-N-phenylaniline (49.6 g, 220.0 mmol), (AMPHOS)2PdCl2 (779 mg, 1.1 mmol), and t-BuONa (24.0 g, 250.0 mmol) were added to 225 mL of o-xylene and stirred at 80°C for 2 hours and at 120°C for 3 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and ethyl acetate was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. The solid obtained after concentration and stirring with a small amount of toluene and hexane was filtered to obtain compound N 1 ,N 3 -bis(4-(tert-butyl)phenyl)-2-chloro-N 1 ,N 3 -diphenylbenzene-1,3-diamine (42.1 g, 75.3 mmol, yield 75%) was obtained.

[0588] Mass [(M+H) + ] : 559

[0589] <Step 2> Synthesis of BD-07

[0590]

[0591] N under a nitrogen stream 1 ,N 3 -bis(4-(tert-butyl)phenyl)-2-chloro-N 1 ,N 3-diphenylbenzene-1,3-diamine (42.1 g, 75.3 mmol) was added to 250 mL of tert-butylbenzene, and tert-butyllithium (53.2 mL, 90.4 mmol, 1.70 M sol. in pentane) was slowly added at -30°C and stirred at 60°C for 3 hours. Next, the mixture was concentrated to remove pentane, cooled to -30°C, and BBr3 (8.7 mL, 90.4 mmol) was slowly added. The reaction mixture was stirred at room temperature for 30 minutes, cooled to 0°C, and then N,N-Diisopropylethylamine (26.2 mL, 150.6 mmol) was added. Next, the mixture was stirred at 120°C for 2 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, ethyl acetate was added, and the organic layer was separated and extracted. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. After concentration, the solid obtained by stirring with a small amount of toluene and hexane was filtered to obtain the compound 5,9-bis(4-(tert-butyl)phenyl)-5,9-dihydro-5,9-diaza-13b-boranaphtho[3,2,1-de]anthracene (10.5 g, 19.7 mmol, yield 26%).

[0592] Mass [(M+H) + ] : 533

[0593]

[0594] [Synthesization Example 30] Synthesis of BD-08

[0595] <Step 1> N 1 ,N 1 ,N 3 ,N 3 -Synthesis of tetrakis(4-(tert-butyl)phenyl)-2-chlorobenzene-1,3-diamine

[0596]

[0597] Under a nitrogen stream, 1-Bromo-2,3-dichlorobenzene (22.6 g, 100 mmol), bis(4-(tert-butyl)phenyl)amine (61.9 g, 220.0 mmol), (AMPHOS)2PdCl2 (779 mg, 1.1 mmol), and t-BuONa (24.0 g, 250.0 mmol) were added to 225 mL of o-xylene and stirred at 80°C for 2 hours and at 120°C for 3 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and ethyl acetate was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. The solid obtained after concentration and stirring in small amounts of toluene and hexane was filtered to obtain compound N 1 ,N 1 ,N 3 ,N 3 -tetrakis(4-(tert-butyl)phenyl)-2-chlorobenzene-1,3-diamine (49.4 g, 73.6 mmol, yield 74%) was obtained.

[0598] Mass [(M+H) + ] : 671

[0599] <Step 2> Synthesis of BD-08

[0600]

[0601] N under a nitrogen stream 1 ,N 1 ,N 3 ,N 349.4 g, 73.6 mmol of tetrakis(4-(tert-butyl)phenyl)-2-chlorobenzene-1,3-diamine (49.4 g, 73.6 mmol) was added to 245 mL of tert-butylbenzene, and tert-butyllithium (52.0 mL, 88.3 mmol, 1.70 M sol. in pentane) was slowly added at -30°C and stirred at 60°C for 3 hours. Next, the mixture was concentrated to remove pentane, cooled to -30°C, and then BBr3 (8.5 mL, 88.3 mmol) was slowly added. The reaction mixture was stirred at room temperature for 30 minutes, cooled back to 0°C, and then N,N-Diisopropylethylamine (25.6 mL, 147.2 mmol) was added. Next, the mixture was stirred at 120°C for 2 hours. After the reaction was completed, the sample was inactivated with a sufficient amount of water, transferred to a separatory funnel, and ethyl acetate was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. After concentration, the solid obtained by stirring with a small amount of toluene and hexane was filtered to obtain the compound 2,12-di-tert-butyl-5,9-bis(4-(tert-butyl)phenyl)-5,9-dihydro-5,9-diaza-13b-boranaphtho[3,2,1-de]anthracene (10.3 g, 16.0 mmol, yield 22%).

[0602] Mass [(M+H) + ] : 645

[0603]

[0604] Synthesis of Electron Transport Auxiliary Layer Materials

[0605] [Synthesization Example 31] Synthesis of Compound ETA-01

[0606]

[0607] <Step 1> Synthesis of ETA-1-i

[0608] 25 g of 2-chloro-4,6-diphenyl-1,3,5-triazine (93.4 mmol, 1 eq), 36.8 g of 2-(8-chlorodibenzo[b,d]furan-4-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (112.1 mmol, 1.2 eq), 4.3 g of Pd(PPh3)4 (3.7 mmol, 0.04 eq), and 25.8 g of K2CO3 (186.8 mmol, 2 eq) were added to 375 ml of THF and 125 ml of H2O and heated under reflux and stirred for 4 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and MC was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, purified by column chromatography, and the compound ETA-1-i, 2-(8-chlorodibenzo[b,d]furan-4-yl)-4,6-diphenyl-1,3,5-triazine (34.4g, yield 85%) was obtained.

[0609] Mass : [(M+H) + ] : 434

[0610] NMR( 1 H): σ= 8.46(4H, m), 8.08(1H, d), 7.88(1H, d), 7.54-7.43(9H, m), 7.20(1H, d)

[0611] <Step 2> Synthesis of ETA-1

[0612] 34.4g (79.4mmol, 1eq) of 2-(8-chlorodibenzo[b,d]furan-4-yl)-4,6-diphenyl-1,3,5-triazine, 40.4g (87.3mmol, 1.1eq) of triphenyl(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)silane, 0.5g (2.4mmol, 0.03eq) of Pd(OAc)2, 3.8g (7.9mmol, 0.1eq) of Xphos, and 24.1g (174.6mmol, 2eq) of K2CO3 were added to 500ml of toluene, 120ml of EtOH, and 120ml of H2O and heated and stirred under reflux for 10 hours. After the reaction was completed, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and MC was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. It was dissolved in toluene and then hexane was added dropwise to produce white crystals, which were filtered to obtain the compound ETA-1, 72,4-diphenyl-6-(8-(4-(triphenylsilyl)phenyl)dibenzo[b,d]furan-4-yl)-1,3,5-triazine (44.3 g, yield 76%).

[0613] Mass : [(M+H) + ] : 734

[0614]

[0615] [Synthesization Example 32] Synthesis of Compound ETA-2

[0616]

[0617] 2,4-diphenyl-6-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-1,3,5-triazine, 25 g (57.4 mmol, 1 eq), 9-chlorospiro[benzo[c]fluorene-7,9'-xanthene], 28.7 g (68.9 mmol, 1.2 eq), Pd(OAc)2, 0.4 g (1.7 mmol, 0.03 eq), Xphos, 2.7 g (5.7 mmol, 0.1 eq), and K2CO3, 15.9 g (114.9 mmol, 2 eq) were added to ml of Toluene, ml of EtOH, and ml of H2O and heated and refluxed for 10 hours. After the reaction was completed, the sample was inactivated with a sufficient amount of water, transferred to a separatory funnel, and MC was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. The sample was dissolved in toluene and hexane was added dropwise to form white crystals, which were then filtered to obtain the compound ETA-2, 2,4-diphenyl-6-(3-(spiro[c]fluorene-7,9'-xanthen]-9-yl)phenyl)-1,3,5-triazine (31.7 g, yield 80%).

[0618] Mass : [(M+H) + ] : 690

[0619]

[0620] [Synthesization Example 33] Synthesis of Compound ETA-3

[0621]

[0622] 25 g (61.3 mmol, 1 eq) of 2-chloro-4-(naphtho[2,1-b]benzofuran-10-yl)-6-phenyl-1,3,5-triazine, 34.0 g (73.6 mmol, 1.2 eq) of triphenyl(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)silane, 2.8 g (2.5 mmol, 0.04 eq) of Pd(PPh3)4, and 16.9 g (122.6 mmol, 2 eq) of K2CO3 were added to 375 ml of toluene, 100 ml of EtOH, and 100 ml of H2O, and heated and stirred under reflux for 8 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and MC was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. The white crystals formed by dissolving in toluene and adding hexane dropwise were filtered to obtain the compound ETA-3, 2-(naphtho[2,1-b]benzofuran-10-yl)-4-phenyl-6-(3-(triphenylsilyl)phenyl)-1,3,5-triazine (33.0 g, yield 76%).

[0623] Mass : [(M+H)+] : 708

[0624]

[0625] [Synthesization Example 34] Synthesis of Compound ETA-4

[0626]

[0627] 25 g (46.1 mmol, 1 eq) of 4-([1,1'-biphenyl]-4-yl)-6-(3,5-dibromophenyl)-2-phenylpyrimidine, 17.7 g (106.0 mmol, 2.3 eq) of 9H-carbazole, 2.1 g (2.3 mmol, 0.05 eq) of Pd2(dba)3, 3.3 g (6.9 mmol, 0.15 eq) of Xphos, and 18.1 g (184.4 mmol, 4.0 eq) of NaOtBu were added to 500 ml of toluene and heated under reflux and stirred for 12 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, and the precipitated solid was filtered and dried. The obtained solid was dissolved in a sufficient amount of MCB, filtered through silica gel, purified by column chromatography, and the compound ETA-4, 9,9'-(5-(6-([1,1'-biphenyl]-4-yl)-2-phenylpyrimidin-4-yl)-1,3-phenylene)bis(9H-carbazole) (23.7 g, yield 72%) was obtained.

[0628] Mass : [(M+H)+] : 715

[0629]

[0630] [Synthesization Example 35] Synthesis of Compound ETA-5

[0631]

[0632] <Step 1> Synthesis of ETA-5-i

[0633] 25 g of 2'-bromo-6'-chloro-1,1':4',1''-terphenyl (73.2 mmol, 1 eq), 38.2 g of 2,4-diphenyl-6-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-1,3,5-triazine (87.8 mmol, 1.2 eq), 3.4 g of Pd(PPh3)4 (2.9 mmol, 0.04 eq), and 20.2 g of K2CO3 (146.3 mmol, 2 eq) were added to 375 ml of THF and 125 ml of H2O and heated and refluxed for 5 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and MC was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography to obtain the compound ETA-5-i, 2-(3'-chloro-5'-phenyl-[1,1':2',1''-terphenyl]-3-yl)-4,6-diphenyl-1,3,5-triazine (35.6 g, yield 85%).

[0634] Mass : [(M+H)+] : 572

[0635] NMR(1H): σ= 8.36(4H, m), 8.26(1H, s), 8.01(1H, s), 7.94(1H, s), 7.75-7.73(3H, m), 7.61(1H, d), 7.51-7.41(14H, m)

[0636] <Step 2> Synthesis of ETA-5

[0637] 35.6 g (62.2 mmol, 1 eq) of 2-(3'-chloro-5'-phenyl-[1,1':2',1''-terphenyl]-3-yl)-4,6-diphenyl-1,3,5-triazine, 31.6 g (68.4 mmol, 1.1 eq) of triphenyl(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)silane, 0.4 g (1.9 mmol, 0.03 eq) of Pd(OAc)2, 3.0 g (6.2 mmol, 0.1 eq) of Xphos, and 18.9 g (136.8 mmol, 2 eq) of K2CO3 were added to 530 ml of toluene, 140 ml of EtOH, and 140 ml of H2O, and heated and stirred under reflux for 10 hours. After the reaction was completed, the sample was inactivated with a sufficient amount of water, transferred to a separatory funnel, and MC was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography. The white crystals formed by dissolving in toluene and adding hexane dropwise were filtered to obtain the compound ETA-5, 2,4-diphenyl-6-(5'-phenyl-3'-(4-(triphenylsilyl)phenyl)-[1,1':2',1''-terphenyl]-3-yl)-1,3,5-triazine (37.4 g, yield 69%).

[0638] Mass : [(M+H)+] : 872

[0639]

[0640] [Synthesization Example 36] Synthesis of Compound ETA-6

[0641]

[0642] 25 g (55.8 mmol, 1 eq) of 2-chloro-4,6-bis(dibenzo[b,d]furan-4-yl)-1,3,5-triazine, 31.0 g (67.0 mmol, 1.2 eq) of triphenyl(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)silane, 2.6 g (2.2 mmol, 0.04 eq) of Pd(PPh3)4, and 15.4 g (111.6 mmol, 2 eq) of K2CO3 were added to 375 ml of THF and 125 ml of H2O and heated and stirred under reflux for 4 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, and the precipitated solid was filtered and dried. The obtained solid was dissolved in a sufficient amount of MCB, filtered through silica gel, purified by column chromatography, and the compound ETA-6, 2,4-bis(dibenzo[b,d]furan-4-yl)-6-(3-(triphenylsilyl)phenyl)-1,3,5-triazine (34.2 g, yield 82%) was obtained.

[0643] Mass : [(M+H)+] : 748

[0644]

[0645] [Synthesization Example 37] Synthesis of Compound ETA-7

[0646]

[0647] 25 g of 2-chloro-4-(dibenzo[b,d]furan-2-yl)-6-(4-(triphenylsilyl)phenyl)-1,3,5-triazine (40.6 mmol, 1 eq), 22.5 g of triphenyl(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)silane (48.7 mmol, 1.2 eq), 1.9 g of Pd(PPh3)4 (1.6 mmol, 0.04 eq), and 11.2 g of K2CO3 (81.1 mmol, 2 eq) were added to 375 ml of THF and 125 ml of H2O and heated under reflux and stirred for 5 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, transferred to a separatory funnel, and MC was added to separate and extract the organic layer. The extracted organic layer was concentrated, adsorbed onto silica gel, and purified by column chromatography to obtain the compound ETA-7, 2-(dibenzo[b,d]furan-2-yl)-4-(3-(triphenylsilyl)phenyl)-6-(4-(triphenylsilyl)phenyl)-1,3,5-triazine (27.9g, yield 75%).

[0648] Mass : [(M+H)+] : 916

[0649]

[0650] [Synthesization Example 38] Synthesis of Compound ETA-8

[0651]

[0652] 25 g (59.5 mmol, 1 eq) of 2-([1,1'-biphenyl]-4-yl)-4-(2-chlorophenyl)-6-phenyl-1,3,5-triazine, 32.6 g (71.4 mmol, 1.2 eq) of 4,4,5,5-tetramethyl-2-(spiro[fluorene-9,9'-xanthen]-2'-yl)-1,3,2-dioxaborolane, 0.4 g (1.8 mmol, 0.03 eq) of Pd(OAc)2, 2.8 g (6.0 mmol, 0.1 eq) of Xphos, and 16.5 g (119.1 mmol, 2 eq) of K2CO3 were added to 375 ml of THF and 125 ml of H2O and heated and stirred under reflux for 6 hours. After the reaction was completed, the reaction was inactivated with a sufficient amount of water, and the precipitated solid was filtered and dried. The obtained solid was dissolved in a sufficient amount of MCB, filtered through silica gel, purified by column chromatography, and the compound ETA-8, 2-([1,1'-biphenyl]-4-yl)-4-phenyl-6-(2-(spiro[fluorene-9,9'-xanthen]-2'-yl)phenyl)-1,3,5-triazine (32.0 g, yield 75%) was obtained.

[0653] Mass : [(M+H)+] : 716

[0654]

[0655] [Synthesization Example 39] Synthesis of Compound ETA-9

[0656]

[0657] 25 g (44.1 mmol, 1 eq) of 2-(3,5-dibromophenyl)-4,6-di(naphthalen-2-yl)-1,3,5-triazine, 16.9 g (101.4 mmol, 2.3 eq) of 9H-carbazole, 2.0 g (2.2 mmol, 0.05 eq) of Pd2(dba)3, 3.2 g (6.6 mmol, 0.15 eq) of Xphos, and 17.3 g (176.3 mmol, 4.0 eq) of NaOtBu were added to 500 ml of toluene and heated under reflux and stirred for 12 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, and the precipitated solid was filtered and dried. The obtained solid was dissolved in a sufficient amount of MCB, filtered through silica gel, purified by column chromatography, and the compound ETA-9, 9,9'-(5-(4,6-di(naphthalen-2-yl)-1,3,5-triazin-2-yl)-1,3-phenylene)bis(9H-carbazole) (23.2 g, yield 68%) was obtained.

[0658] Mass : [(M+H)+] : 740

[0659]

[0660] [Synthesization Example 40] Synthesis of Compound ETA-10

[0661]

[0662] 25 g (56.3 mmol, 1 eq) of 2-(2-chlorophenyl)-4,6-di(naphthalen-2-yl)-1,3,5-triazine, 31.0 g (67.6 mmol, 1.2 eq) of 4,4,5,5-tetramethyl-2-(spiro[fluorene-9,9'-xanthen]-2'-yl)-1,3,2-dioxaborolane, 0.4 g (1.7 mmol, 0.03 eq) of Pd(OAc)2, 2.7 g (5.6 mmol, 0.1 eq) of Xphos, and 15.6 g (112.6 mmol, 2 eq) of K2CO3 were added to 375 ml of THF and 125 ml of H2O and heated and stirred under reflux for 6 hours. After the reaction was completed, the reaction was inactivated with a sufficient amount of water, and the precipitated solid was filtered and dried. The obtained solid was dissolved in a sufficient amount of MCB, filtered through silica gel, purified by column chromatography, and the compound ETA-10, 2,4-di(naphthalen-2-yl)-6-(2-(spiro[fluorene-9,9'-xanthen]-2'-yl)phenyl)-1,3,5-triazine (27.5 g, yield 66%) was obtained.

[0663] Mass : [(M+H)+] : 740

[0664]

[0665] [Synthesization Example 41] Synthesis of Compound ETA-11

[0666]

[0667] 20 g (58.2 mmol, 1 eq) of 2-(2-chlorophenyl)-4,6-diphenyl-1,3,5-triazine, 33.1 g (69.8 mmol, 1.2 eq) of 2-(9,9'-spirobi[xanthen]-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, 0.4 g (1.7 mmol, 0.03 eq) of Pd(OAc)2, 2.8 g (5.8 mmol, 0.1 eq) of Xphos, and 16.1 g (116.3 mmol, 2 eq) of K2CO3 were added to 400 ml of THF and 150 ml of H2O and heated and stirred under reflux for 6 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, and the precipitated solid was filtered and dried. The obtained solid was dissolved in a sufficient amount of MCB, filtered through silica gel, purified by column chromatography, and the compound ETA-11, 2-(2-(9,9'-spirobi[xanthen]-2-yl)phenyl)-4,6-diphenyl-1,3,5-triazine (29.0 g, yield 76%) was obtained.

[0668] Mass : [(M+H)+] : 656

[0669]

[0670] [Synthesization Example 42] Synthesis of Compound ETA-12

[0671]

[0672] 20 g of 2-(3-bromophenyl)-4,6-diphenyl-1,3,5-triazine (51.5 mmol, 1 eq), 36.1 g of 4,4,5,5-tetramethyl-2-(3',4',5'-triphenyl-[1,1':2',1''-terphenyl]-3-yl)-1,3,2-dioxaborolane (61.8 mmol, 1.2 eq), 2.4 g of Pd(PPh3)4 (2.1 mmol, 0.04 eq), and 14.2 g of K2CO3 (103.0 mmol, 2 eq) were added to 400 ml of THF and 150 ml of H2O and heated and stirred under reflux for 6 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, the precipitated solid was filtered, and the mixture was thoroughly dried. The solid was dissolved in MCB, filtered through silica gel, and purified by column chromatography to obtain the compound ETA-12, 2,4-diphenyl-6-(4',5',6'-triphenyl-[1,1':2',1'':3'',1'''-quaterphenyl]-3'''-yl)-1,3,5-triazine (31.6 g, yield 80%).

[0673] Mass : [(M+H)+] : 766

[0674]

[0675] [Synthesization Example 43] Synthesis of Compound ETA-13

[0676]

[0677] 20 g of 4-([1,1'-biphenyl]-4-yl)-6-(3-bromophenyl)-2-phenylpyrimidine (43.2 mmol, 1 eq), 22.4 g of 2-([1,1':2',1'':2'',1'''-quaterphenyl]-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (51.8 mmol, 1.2 eq), 2.0 g of Pd(PPh3)4 (1.7 mmol, 0.04 eq), and 11.9 g of K2CO3 (86.3 mmol, 2 eq) were added to 400 ml of THF and 150 ml of H2O and heated and stirred under reflux for 6 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, the precipitated solid was filtered, and the mixture was thoroughly dried. The solid was dissolved in MCB, filtered through silica gel, and purified by column chromatography to obtain the compound ETA-13, 4-([1,1'-biphenyl]-4-yl)-6-([1,1':2',1'':2'',1''':2'',1''''-quinquephenyl]-3-yl)-2-phenylpyrimidine (22.0 g, yield 74%).

[0678] Mass : [(M+H)+] : 689

[0679]

[0680] [Synthesization Example 44] Synthesis of Compound ETA-14

[0681]

[0682] 20 g (45.6 mmol, 1 eq) of 2-(3-bromophenyl)-4-(naphthalen-1-yl)-6-phenyl-1,3,5-triazine, 23.7 g (54.8 mmol, 1.2 eq) of 2-([1,1':2',1'':2'',1'''-quaterphenyl]-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, 21 g (1.8 mmol, 0.04 eq) of Pd(PPh3)4, and 12.6 g (91.3 mmol, 2 eq) of K2CO3 were added to 400 ml of THF and 150 ml of H2O and heated and stirred under reflux for 6 hours. After the reaction was complete, the mixture was inactivated with a sufficient amount of water, the precipitated solid was filtered, and the mixture was thoroughly dried. The solid was dissolved in MCB, filtered through silica gel, and purified by column chromatography to obtain the compound ETA-14, 2-([1,1':2',1'':2'',1''':2'',1''''-quinquephenyl]-3-yl)-4-(naphthalen-1-yl)-6-phenyl-1,3,5-triazine (21.2 g, yield 70%).

[0683] Mass : [(M+H)+] : 664

[0684]

[0685] [Synthesization Example 45] Synthesis of Compound ETA-15

[0686]

[0687] 25 g (59.5 mmol, 1 eq) of 2-(3'-chloro-[1,1'-biphenyl]-3-yl)-4,6-diphenyl-1,3,5-triazine, 21.0 g (65.5 mmol, 1.1 eq) of 2-(9,9-dimethyl-9H-fluoren-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, 0.4 g (1.8 mmol, 0.03 eq) of Pd(OAc)2, 2.8 g (6.0 mmol, 0.10 eq) of Xphos, and 16.5 g (119.1 mmol, 2 eq) of K2CO3 were added to 400 ml of toluene, 100 ml of EtOH, and 100 ml of H2O and heated and stirred under reflux for 7 hours. After the reaction was completed, the reaction was inactivated with a sufficient amount of water, and the precipitated solid was filtered and thoroughly dried. The solid was dissolved in MCB, filtered through silica gel, purified by column chromatography, and concentrated. The concentrated solid was dissolved in toluene, and then HX was added dropwise. The resulting solid was filtered to obtain the compound ETA-15, 2-(3'-(9,9-dimethyl-9H-fluoren-2-yl)-[1,1'-biphenyl]-3-yl)-4,6-diphenyl-1,3,5-triazine (26.5 g, yield 77%).

[0688] Mass : [(M+H)+] : 578

[0689]

[0690] [Synthesization Example 46] Synthesis of Compound ETA-16

[0691]

[0692] 25 g (48.1 mmol, 1 eq) of 2-(3-(3-chloronaphthalen-1-yl)phenyl)-4-(naphthalen-2-yl)-6-phenyl-1,3,5-triazine, 16.9 g (52.9 mmol, 1.1 eq) of 2-(9,9-dimethyl-9H-fluoren-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, 0.3 g (1.4 mmol, 0.03 eq) of Pd(OAc)2, 2.3 g (4.8 mmol, 0.10 eq) of Xphos, and 13.3 g (96.1 mmol, 2 eq) of K2CO3 were added to 400 ml of toluene, 100 ml of EtOH, and 100 ml of H2O and heated and stirred under reflux for 7 hours. After the reaction was completed, the reaction was inactivated with a sufficient amount of water, and the precipitated solid was filtered and thoroughly dried. The solid was dissolved in MCB, filtered through silica gel, purified by column chromatography, and concentrated. The concentrated solid was dissolved in toluene, and then HX was added dropwise. The resulting solid was filtered to obtain the compound ETA-16, 2-(3-(3-(9,9-dimethyl-9H-fluoren-2-yl)naphthalen-1-yl)phenyl)-4-(naphthalen-2-yl)-6-phenyl-1,3,5-triazine (24.4 g, yield 75%).

[0693] Mass : [(M+H)+] : 678

[0694]

[0695] <Synthesis of Electron Transport Layer Materials>

[0696] [Synthesization Example 47] Synthesis of Compound ETL-01

[0697]

[0698] 20 g (34 mmol, 1.0 eq) of ETL-01-i, 21.6 g (78.2 mmol, 2.3 eq) of 2-chloro-4,6-diphenyl-1,3,5-triazine, 42.0 g (1.7 mmol, 0.6 eq) of Pd(PPh3), and 14.1 g (102 mmol, 3.0 eq) of K2CO3 were added to 200 ml of toluene, 40 ml of EtOH, and 40 ml of H2O, and stirred at 100°C for 9 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound ETL-01 (36.2 g, yield 75%) was obtained by column chromatography.

[0699] Mass : [(M+H) + ] : 799

[0700]

[0701] [Synthesization Example 48] Synthesis of Compound ETL-03

[0702]

[0703] <Step 1> Synthesis of ETL-03-ii

[0704] 30 g of ETL-03-iii (60.4 mmol, 1.0 eq), 18.4 g of 2-chloro-4,6-diphenyl-1,3,5-triazine (66.4 mmol, 1.1 eq), 42.8 g of Pd(PPh3) (2.4 mmol, 0.5 eq), and 25.0 g of K2CO3 (181.1 mmol, 3.0 eq) were added to 450 ml of toluene, 90 ml of EtOH, and 90 ml of H2O, and stirred at 100°C for 5 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound ETL-03-ii (30.5 g, yield 84%) was obtained by column chromatography.

[0705] Mass : [(M+H) + ] : 602

[0706] NMR(1 H): σ=8.38-8.36(5H, m), 7.96(1H, s), 7.56-7.38(22H, m)

[0707] <Step 2> Synthesis of ETL-03-i

[0708] 30.5 g (50.7 mmol, 1.0 eq) of ETL-03-ii, 18.4 g (66.4 mmol, 1.2 eq) of 4,4,4',4',5,5,5',5'-octamethyl-2,2'-bi(1,3,2-dioxaborolane), 32.8 g (3.0 mmol, 0.05 eq) of Pd2(dba) and 11.9 g (121.7 mmol) of KOAc were added to 300 ml of 1,4-dioxane and stirred at 100°C for 5 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, the compound ETL-03-i (24.3 g, yield 69%) was obtained by column chromatography.

[0709] Mass : [(M+H) + ] : 694

[0710] NMR( 1 H): σ=8.38-8.36(5H, m), 7.96(1H, s), 7.56-7.38(22H, m)

[0711] <Step 3> Synthesis of ETL-03

[0712] 24.3 g (35.0 mmol, 1.0 eq) of ETL-03-i, 10.3 g (38.5 mmol, 1.1 eq) of 5-chloro-2,3-diphenylpyrazine, 41.2 g (1.0 mmol, 0.03 eq) of Pd(PPh3) and 10.6 g (77.0 mmol, 2.0 eq) of K2CO3 were added to 450 ml of toluene, 120 ml of EtOh, and 120 ml of H2O, and stirred at 100°C for 6 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, the compound ETL-03-i (23.5 g, yield 84%) was obtained by column chromatography.

[0713] Mass : [(M+H)+] : 798

[0714]

[0715] [Synthesization Example 49] Synthesis of Compound ETL-07

[0716]

[0717]

[0718] 4.98 g of ETL-07-i (10 mmol, 1.0 eq), 2.74 g of [1,1':2',1''-terphenyl]-4-ylboronic acid (10 mmol, 1.0 eq), 40.34 g of Pd(PPh3) (0.3 mmol, 0.03 eq), and 2.76 g of K2CO3 (20 mmol, 2.0 eq) were added to 40 ml of toluene, 10 ml of EtOH, and 10 ml of H2O and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound ETL-07 (5.2 g, yield 75%) was obtained by column chromatography.

[0719] Mass : [(M+H)+] : 692

[0720]

[0721] [Synthesization Example 50] Synthesis of Compound ETL-08

[0722]

[0723] 4.98 g of ETL-08-i (10 mmol, 1.0 eq), 2.74 g of [1,1':3',1''-terphenyl]-5'-ylboronic acid (10 mmol, 1.0 eq), 40.34 g of Pd(PPh3) (0.3 mmol, 0.03 eq), and 2.76 g of K2CO3 (20 mmol, 2.0 eq) were added to 40 ml of toluene, 10 ml of EtOH, and 10 ml of H2O, and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound ETL-08 (5.5 g, yield 79%) was obtained by column chromatography.

[0724] Mass : [(M+H) + ] : 692

[0725]

[0726] [Synthesization Example 51] Synthesis of Compound ETL-09

[0727]

[0728] 4.94 g (10 mmol, 1.0 eq) of ETL-09-i, 3.50 g (10 mmol, 1.0 eq) of [1,1':2',1'':3'',1'''-quaterphenyl]-3'''-ylboronic acid, 40.34 g (0.3 mmol, 0.03 eq) of Pd(PPh3), and 2.76 g (20 mmol, 2.0 eq) of K2CO3 were added to 40 ml of toluene, 10 ml of EtOH, and 10 ml of H2O, and stirred at 100°C for 8 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound ETL-09 (7.3 g, yield 96%) was obtained by column chromatography.

[0729] Mass : [(M+H) + ] : 768

[0730]

[0731] [Synthesization Example 52] Synthesis of Compound ETL-11

[0732]

[0733] 30.0 g (64.6 mmol, 1.0 eq) of ETL-11-i, 36.3 g (71.1 mmol, 1.1 eq) of 2-([1,1'-biphenyl]-2-yl)-4-phenyl-6-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-1,3,5-triazine, 3.0 g (2.6 mmol, 0.04 eq) of Pd(PPh3)4, and 17.9 g (129.2 mmol, 2.0 eq) of K2CO3 were added to 450 ml of toluene, 120 ml of EtOH, and 120 ml of H2O, and stirred at 100°C for 8 hours. After the reaction was complete, the precipitated solid was filtered. The obtained solid was dissolved in chlorobenzene, and then the compound ETL-11 (39.7 g, yield 80%) was obtained using column chromatography.

[0734] Mass : [(M+H) + ] : 769

[0735]

[0736] [Synthesization Example 53] Synthesis of Compound ETL-12

[0737]

[0738] 30.0 g (71.4 mmol, 1.0 eq) of ETL-12-i, 34.2 g (78.6 mmol, 1.1 eq) of 2,4-diphenyl-6-(2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-1,3,5-triazine, 20.5 g (2.1 mmol, 0.03 eq) of Pd(OAc), 3.4 g (7.1 mmol, 0.1 eq) of Xphos, and 19.7 g (142.9 mmol, 2.0 eq) of K2CO3 were added to 450 ml of toluene, 120 ml of EtOH, and 120 ml of H2O, and stirred at 100°C for 4 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound ETL-12 (30.3 g, yield 59%) was obtained using column chromatography.

[0739] Mass : [(M+H) + ] : 717.84

[0740]

[0741] [Synthesization Example 54] Synthesis of Compound ETL-13

[0742]

[0743] 20.0 g (51.5 mmol, 1.0 eq) of ETL-13-i, 23.5 g (54.1 mmol, 1.05 eq) of 2,4-diphenyl-6-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-1,3,5-triazine, 42.4 g (2.1 mmol, 0.04 eq) of Pd(PPh3), and 14.2 g (103.0 mmol, 2.0 eq) of K2CO3 were added to 300 ml of toluene, 80 ml of EtOH, and 80 ml of H2O, and stirred at 100°C for 8 hours. After the reaction was complete, the precipitated solid was filtered. The obtained solid was dissolved in chlorobenzene, and then the compound ETL-13 (27.3 g, yield 86%) was obtained using column chromatography.

[0744] Mass : [(M+H) + ] : 616.73

[0745]

[0746] [Synthesization Example 55] Synthesis of Compound ETL-17

[0747]

[0748] 20.0 g (47.6 mmol, 1.0 eq) of ETL-17-i, 21.8 g (50.0 mmol, 1.05 eq) of 2,4-diphenyl-6-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-1,3,5-triazine, 42.2 g (1.9 mmol, 0.04 eq) of Pd(PPh3), and 13.2 g (95.3 mmol, 2.0 eq) of K2CO3 were added to 300 ml of toluene, 80 ml of EtOH, and 80 ml of H2O, and stirred at 100°C for 8 hours. After the reaction was complete, the precipitated solid was filtered. The obtained solid was dissolved in chlorobenzene, and then compound ETL-17 (27.4 g, yield 83%) was obtained using column chromatography.

[0749] Mass : [(M+H)+] : 692.83

[0750]

[0751] [Synthesization Example 56] Synthesis of Compound ETL-18

[0752]

[0753] 20.0 g (41.2 mmol, 1.0 eq) of ETL-18-i, 22.4 g (45.3 mmol, 1.1 eq) of 6-(4-chloro-2-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-2-naphthonitrile, 20.3 g (1.2 mmol, 0.34 eq) of Pd(OAc), 2.9 g (6.2 mmol, 0.15 eq) of Xphos, and 11.4 g (82.4 mmol, 2.0 eq) of K2CO3 were added to 300 ml of toluene, 80 ml of EtOH, and 80 ml of H2O, and stirred at 100°C for 3 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound ETL-18 (21.2 g, yield 61%) was obtained using column chromatography.

[0754] Mass : [(M+H)+] : 817.96

[0755]

[0756] [Synthesization Example 57] Synthesis of Compound ETL-19

[0757]

[0758] 20.0 g (41.2 mmol, 1.0 eq) of ETL-18-i, 20.2 g (45.3 mmol, 1.1 eq) of 2'-chloro-6'-(4,6-diphenyl-1,3,5-triazin-2-yl)-[1,1'-biphenyl]-4-carbonitrile, 20.3 g (1.2 mmol, 0.34 eq) of Pd(OAc), 2.9 g (6.2 mmol, 0.15 eq) of Xphos, and 11.4 g (82.4 mmol, 2.0 eq) of K2CO3 were added to 300 ml of toluene, 80 ml of EtOH, and 80 ml of H2O, and stirred at 100°C for 3 hours. After the reaction was complete, the mixture was extracted with methylene chloride, MgSO4 was added, and the solution was filtered. After removing the solvent from the filtered organic layer, compound ETL-19 (20.6 g, yield 65%) was obtained using column chromatography.

[0759] Mass : [(M+H)+] : 767.9

[0760]

[0761] [Synthesization Example 58] Synthesis of Compound ETL-20

[0762]

[0763] 20.0 g (47.6 mmol, 1.0 eq) of ETL-20-i, 2-(naphthalen-2-yl)-4-phenyl-6-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-1,3,5-triazine, 24.3 g (50.0 mmol, 1.05 eq) of 2-(naphthalen-2-yl)-42.2 g (1.9 mmol, 0.04 eq) of Pd(PPh3) and 13.2 g (95.3 mmol, 2.0 eq) of K2CO3 were added to 300 ml of toluene, 80 ml of EtOH, and 80 ml of H2O, and stirred at 100°C for 8 hours. After the reaction was complete, the precipitated solid was filtered. The obtained solid was dissolved in toluene, and the compound ETL-20 (25.1 g, yield 71%) was obtained using column chromatography.

[0764] Mass : [(M+H) + ] : 742.89

[0765]

[0766] [Preparation (Calculation) Example]

[0767] The physical properties of each compound synthesized in Synthesis Examples 1 to 58 above were calculated according to the method described below and are shown in Table 1 below.

[0768] Specifically, the HOMO energy level, LUMO energy level, and singlet (S1) and triplet (T1) energies of the compounds used in the present invention were each calculated according to the Gaussian formula (#B3LYP / 6-31G*). In addition, the HOMO energy level and LUMO energy level of each compound were expressed as absolute values. At this time, the basic calculation method for each physical property was performed using the Schrödinger software release 2022-3, and the B3LYP (Becke, 3-parameter, Lee-Yang-Parr) functional calculation method from Density Functional Theory (DFT) was used, and 6-31G* was used as the basis set.

[0769] Materials HOMOLUMOS1T1 1st Host BPH-014.940.933.583.02 BPH-024.930.743.723.02 BPH-034.750.773.582.85 BPH-045.060.953.583.08 BPH-055.441.253.623.10 BPH-065.260.883.853.0 8BPH-074.971.323.242.58BPH-084.920.783.612.82BPH-094.921.273.152.63 BPH-105.011.033.482.58BPH-114.931.133.522.71BPH-124.761.193.122.492nd Host BNH-015.751.863.323.12BNH-025.551.703.253.06BNH-035.661.883.203.05BNH-045.611.643.402.97BNH-055.391.942.972.80BNH-065.771.903.293.03BNH-075.751.953.252.47BNH-085.321.932.892.41BNH-095.351.872.932.32BNH-105.392.012.902.39 Dopant PTB-054.711.312.842.61 PTB-064.811.352.782.58 PTB-074.671.292.822.60 PTB-084.531.702.372.17 The 2 Dopant BD-054.681.043.112.64 BD-064.771.083.152.67 BD-074.681.023.132.63 BD-084.580.983.082.59 Electron Transport Auxiliary Layer ETA-015.891.893.572.83 ETA-025.411.793.262.34 ETA-035.661.803.452.57 ETA-045.521.973.032.82 ETA-055.821.76 3.612.99ETA-066.001.863.662.82ETA-076.101.843.762.96ETA-085.601.813.252.81ETA-095.452.142.902.44ET A-105.561.853.202.48ETA-115.581.743.362.99ETA-125.811.793.692.97ETA-135.941.653.802.85ETA-145.811.813.492.47 ETA-155.581.823.442.83 ETA-165.431.923.192.49 Electron Transport Layer ETL-016.511.834.053.02 ETL-035.831.793.702.73 ETL-075.971.943.652.94 ETL-086.071.973.622.91 ETL-095.851.953 .482.95ETL-115.931.903.572.75ETL-126.291.993.732.95ETL-136.211.863.852.93ETL-175. 991.973.612.84ETL-185.952.043.432.49ETL-195.931.943.542.50ETL-205.921.963.482.50.

[0770] At this time, the structure of each compound constituting the first host, second host, first dopant, second dopant, electron transport auxiliary layer, and electron transport layer material used in Examples 1 to 50 of the present invention is as follows.

[0771]

[0772]

[0773]

[0774]

[0775]

[0776]

[0777]

[0778] In addition, each compound constituting the blue organic electroluminescent device according to the embodiments and comparative examples of the present invention is as follows.

[0779]

[0780]

[0781] [Examples 1–50] Fabrication of Blue Organic Electroluminescent Devices

[0782] After purifying the compound synthesized in the above synthesis example to high purity through sublimation using a commonly known method, a blue organic electroluminescent device was fabricated according to the following process.

[0783] First, a glass substrate coated with a thin film of ITO (Indium tin oxide) to a thickness of 1200 Å was cleaned with distilled water ultrasonics. After the distilled water cleaning was finished, the substrate was ultrasonically cleaned with a solvent such as isopropyl alcohol, acetone, or methanol and dried, then transferred to a UV OZONE cleaner (Power sonic 405, Hwashin Tech), cleaned with UV light for 5 minutes, and then transferred to a vacuum deposition machine.

[0784] An organic electroluminescent device was fabricated by stacking HI + 2% HAT-CN6 (10 Å) / HI (600 Å) / EB (200 Å) / 88 wt% host (first host : second host = 40 : 60 wt ratio) + 10 wt% first dopant + 2 wt% second dopant (300 Å) / electron transport auxiliary layer (50 Å) / electron transport layer + Liq (1:1) (300 Å) / LiF (10 Å) / Al (200 Å) in that order on an ITO transparent electrode prepared as above.

[0785] At this time, the first host, second host, first dopant, second dopant, electron transport auxiliary layer material, and electron transport layer material of the light-emitting layer used in Examples 1 to 50 are as shown in Table 2 below.

[0786]

[0787] [Comparative Examples 1–22] Fabrication of Blue Organic Electroluminescent Devices

[0788] Organic electroluminescent devices of Comparative Examples 1 to 22 were manufactured by performing the same procedure as Example 1, except that the light-emitting layer material, the electron transport auxiliary layer material, and the electron transport layer material were changed as shown in Table 2 below.

[0789] Specifically, Comparative Examples 1 to 22 manufactured organic electroluminescent devices by stacking HI + 2% HAT-CN6 (10 Å) / HI (600 Å) / EB (200 Å) / 88 wt% host (first host : second host = 40 : 60 wt ratio) + 10 wt% first dopant + 2 wt% second dopant (300 Å) / electron transport auxiliary layer (50 Å) / electron transport layer + Liq (1:1) (300 Å) / LiF (10 Å) / Al (200 Å) in that order on an ITO transparent electrode prepared as above.

[0790]

[0791] [Evaluation Example]

[0792] For the organic electroluminescent devices prepared in Examples 1 to 50 and Comparative Examples 1 to 22, respectively, the driving voltage, current efficiency, lifetime, emission wavelength, and full width at a current density of 10 mA / cm² were measured, and the results are shown in Table 2 below.

[0793] Example 1 Host 2 Host 1 Dopant 2 Dopant Electron Transport Auxiliary Layer Electron Transport Layer Voltage (V) Efficiency (cd / A) Lifetime (T90) Emission Wavelength (nm) Half Width (nm) Example 1 BPH-01BNH-01BD-05PTB-05ETA-01ETL-074.213715746046 Example 2 BPH-01BNH-01BD-05PTB-05ETA-01ETL-084.313615246046 Example 3 BPH-01BNH-02BD-05PTB-07ETA-01ETL-074.313315946046 Example 4 BPH-01BN H-02BD-05PTB-07ETA-01ETL-094.313216646046 Example 5 BPH-02BNH-03BD-06PTB-05ETA-01ETL-074.313116746046 Example 6 BPH-02BNH-03BD-06PTB-05ETA-01ETL-124.313115646046 Example 7 BPH-01BNH-01BD-08PTB-07ETA-04ETL-174.212213346046 Example 8 BPH-01BNH-01BD-08PTB-07ETA-04ETL-124.2 12111946046Example 9 BPH-02BNH-03BD-06PTB-06ETA-04ETL-084.213311046046Example 10 BPH-02BNH-03BD-06PTB-06ETA-04ETL-124.114110946046Example 11 BPH-02BNH-03BD-06PTB-05ETA-04ETL-084.312916046046Example 12 BPH-02BNH-03BD-06PTB-05ETA-04ETL-174.212515146046Example 13 BPH-04BNH-0 6BD-06PTB-05ETA-05ETL-014.313014246046 Example 14 BPH-04BNH-06BD-06PTB-05ETA-05ETL-074.414416946046 Example 15 BPH-02BNH-03BD-07PTB-05ETA-05ETL-094.314015146046 Example 16 BPH-02BNH-03BD-07PTB-05ETA-05ETL-134.312815046046 Example 17 BPH-08BNH-04BD-06PTB-05ETA-05ETL-014.214211646046Example 18 BPH-08BNH-04BD-06PTB-05ETA-05ETL-134.314013846046Example 19 BPH-01BNH-02BD-05PTB-07ETA-06ETL-084.313715746046Example 20 BPH-01BNH-02BD-05PTB-07ETA-06ETL-074.213014946046Example 21 BPH-02BNH-03BD-06PTB-05ETA-06ETL-084.312513346046Example 22 BPH-02BNH- 03BD-06PTB-05ETA-06ETL-094.312614346046 Example 23 BPH-06BNH-03BD-06PTB-05ETA-07ETL-124.311913346046 Example 24 BPH-06BNH-03BD-06PTB-05ETA-07ETL-134.212213746046 Example 24 BPH-06BNH-03BD-06PTB-05ETA-07ETL-174.314013546046 Example 25 BPH-01BNH-02BD-05PTB-05ETA-07ETL-094. 214310546046Example 25 BPH-01BNH-02BD-05PTB-05ETA-07ETL-124.313515046046Example 26 BPH-01BNH-02BD-05PTB-05ETA-07ETL-174.313316246046Example 27 BPH-02BNH-03BD-05PTB-07ETA-08ETL-014.212215446046Example 28 BPH-02BNH-03BD-05PTB-07ETA-08ETL-074.313311846046Example 29 BPH-06BNH- 03BD-06PTB-05ETA-08ETL-014.111613546046 Example 30 BPH-06BNH-03BD-06PTB-05ETA-08ETL-094.313714846046 Example 31 BPH-01BNH-02BD-05PTB-05ETA-08ETL-014.212414546046 Example 32 BPH-01BNH-02BD-05PTB-05ETA-08ETL-134.212615046046 Example 33 BPH-08BNH-06BD-05PTB-07ETA-11ETL-014.312215546046Example 34 BPH-08BNH-06BD-05PTB-07ETA-11ETL-134.313314046046Example 35 BPH-04BNH-06BD-06PTB-05ETA-11ETL-014.212116046046Example 36 BPH-04BNH-06BD-06PTB-05ETA-11ETL-134.212915446046Example 37 BPH-02BNH-03BD-06PTB-06ETA-12ETL-014.213014446046Example 38 BPH-02BNH -03BD-06PTB-06ETA-12ETL-134.213113446046 Example 39 BPH-08BNH-04BD-06PTB-05ETA-12ETL-014.212215446046 Example 40 BPH-08BNH-04BD-06PTB-05ETA-12ETL-134.312614946046 Example 41 BPH-01BNH-02BD-07PTB-05ETA-12ETL-084.313314346046 Example 42 BPH-01BNH-02BD-07PTB-05ETA-12ETL-174 .313614046046Example 43BPH-02BNH-03BD-05PTB-07ETA-13ETL-014.412317046046Example 44BPH-02BNH-04BD-06PTB-05ETA-13ETL-014.412916146046Example 45BPH-04BNH-06BD-06PTB-06ETA-13ETL-014.412815646046Example 46BPH-04BNH-06BD-06PTB-05ETA-15ETL-074.314015746046Example 47BPH-04BNH -06BD-06PTB-05ETA-15ETL-084.314315946046 Example 48 BPH-01BNH-02BD-05PTB-05ETA-15ETL-094.211816246046 Example 49 BPH-01BNH-02BD-05PTB-05ETA-15ETL-124.212214846046 Example 50 BPH-01BNH-01BD-08PTB-07ETA-15ETL-174.313713546046 Comparative Example 1 BPH-07BNH-05BD-05PTB-05ETA-01ETL-014.51019946048Comparative Example 2 BPH-06BNH-05BD-05PTB-07ETA-08ETL-034.5888046248Comparative Example 3 BPH-07BNH-05BD-06PTB-05ETA-10ETL-014.6705146349Comparative Example 4 BPH-07BNH-09BD-08PTB-07ETA-11ETL-174.7715545850Comparative Example 5 BPH-07BNH-09BD-08PTB-07ETA-11ETL-074.8553346051Comparative Example 6 BPH-07BNH-09BD-08PTB-07ETA -11ETL-084.6795646149Comparative Example 7BPH-01BNH-02BD-06PTB-06ETA-02ETL-034.6504246450Comparative Example 8BPH-01BNH-02BD-06PTB-06ETA-02ETL-114.5514446250Comparative Example 9BPH-02BNH-04BD-06PTB-05ETA-03ETL-184.8392046651Comparative Example 10BPH-02BNH-04BD-06PTB-05ETA-03ETL-194.6622246248Comparative Example 11BPH-09BNH-08BD -07PTB-05ETA-06ETL-014.6605546347Comparative Example 12BPH-09BNH-08BD-07PTB-05ETA-06ETL-114.5331946748Comparative Example 13BPH-09BNH-08BD-06PTB-05ETA-07ETL-194.5664746248Comparative Example 14BPH-09BNH-08BD-06PTB-05ETA-07ETL-114.5402946548Comparative Example 15BPH-01BNH-01BD-08PTB-07ETA-09ETL-135.020847048Comparative Example 16 BPH-01BNH-01BD-08PTB-07ETA-09ETL-125.1211646949Comparative Example 17 BPH-01BNH-02BD-08PTB-06ETA-14ETL-034.6606246348Comparative Example 18 BPH-01BNH-02BD-08PTB-06ETA-14ETL-204.7574346348Comparative Example 19 BPH-07BNH-05BD-06PTB-05ETA-16ETL-134.8221446649Comparative Example 20 BPH-07BNH-05BD-06PTB-05ETA-16ETL-204.5333046248Comparative Example 21BPH-02BNH-04BD-06PTB-05ETA-13ETL-124.81008846048Comparative Example 22BPH-04BNH-06BD-06PTB-06ETA-13ETL-174.81039646048.

[0794] As described in Table 2 above, it was confirmed that the organic electroluminescent devices of Examples 1 to 50, which include a first- and second host, a first- and second dopant, and an electron transport auxiliary layer controlled to specific physical properties as essential components, exhibit significant effects in terms of driving voltage, efficiency characteristics, and lifespan characteristics compared to the organic electroluminescent devices of Comparative Examples 1 to 22. Specifically, in the case of Comparative Examples 3 to 20, which include a light-emitting layer with a low triplet (T1) energy level of the host material, it was confirmed that the efficiency and lifespan characteristics of the device are significantly degraded. Furthermore, in the case of Comparative Examples 9-10, 12, 15-16, and 19-20, in which the T1 of the electron transport auxiliary layer and the electron transport layer is low, it was confirmed that the lifespan characteristics of the device tend to decrease rapidly. This suggests that because the T1 energy level is low, energy transfer from the emissive layer is not effectively transferred to the dopant's T1, and light absorption occurs due to the T1 being lower than the blue emission wavelength. Furthermore, in the case of Comparative Examples 15, 16, 19, and 20, where the LUMO energy of the electron transport assist layer is deep, the efficiency characteristics of the device tended to decrease or the driving voltage increased. This indicates that while the emission wavelength and full width at half maximum (FWHM) shape are maintained and the color deviation is not significant as the first dopant and second dopant are present at the LUMO energy level of the first host that accepts electrons within the emissive layer, it can be confirmed that the efficiency characteristics of the device deteriorate when the energy level of the host is not included within a predetermined range. In other words, it can be inferred that the energy transfer from the host to the dopant is not smooth, leading to an overall increase in voltage, a decrease in efficiency, and a reduction in lifespan of the device.

[0795] Meanwhile, it can be observed that changes in emission wavelength and full width at half maximum become more pronounced depending on the energy level of the host. This can be attributed to the fact that the energy transfer to the dopant is not smooth due to the low energy levels of the host's self-luminescence and triplet (T1), resulting in non-uniform light wavelengths, a larger full width at half maximum, reduced color purity, and a decrease in the efficiency characteristics of the device. In particular, if the energy levels of the first and second hosts are not controlled within a predetermined range, the device exhibits disadvantages in terms of driving voltage; this is because the driving voltage becomes unfavorable due to the charge barrier caused by the difference in energy levels.

[0796] Similarly, when the triplet (T1) energy level of the host is low, the overall efficiency characteristics of the device decrease, and the lifespan characteristics are significantly affected. This is because even if a sufficient amount of excitons are generated, the low triplet (T1) level causes host autoluminescence or losses due to triplet-triplet annihilation (TTA), which significantly affects the reduction in device efficiency. Furthermore, these non-radiative energy transfers release thermal energy throughout the device, accelerating device degradation. Additionally, the voltage of the device is mainly influenced by LUMO energy, and the efficiency and lifespan characteristics of the device show distinct deviations depending on the triplet (T1) energy level.

[0797] In the light-emitting system of the aforementioned type, the energy levels between each layer constituting the device and the deviations between them are important, and it can be seen that if any of these do not satisfy the essential physical property values ​​according to the present invention, it is difficult to actually realize an excellent blue light-emitting device. Accordingly, in order to secure optimized characteristics in terms of luminous efficiency and lifespan characteristics of a blue phosphorescent light-emitting device, it is necessary to include a plurality of hosts, a plurality of hosts, an electron transport assist layer, and an electron transport layer devised in the present invention, and to simultaneously possess appropriate HOMO energy levels (HOMO), LUMO energy levels (LUMO), and triplet (T1) energy levels at a level where excitons do not reverse transition between each of these materials, while also having a specific gap between each energy level as an essential component. In particular, it was confirmed that there is a significant improvement in the overall efficiency and lifespan characteristics of the device depending on the LUMO energy level (LUMO), triplet (T1) energy level, and electron transport performance of the electron transport assist layer.

[0798] Although the present invention has been described with reference to the aforementioned synthesis examples and embodiments, it should be understood that these are merely illustrative and not limiting. Accordingly, those skilled in the art to which the present invention pertains can understand that various modifications and equivalent alternative embodiments are possible therefrom, and consequently, the technical scope of protection of the present invention should be determined by the technical concept of the appended claims.

Claims

An organic electroluminescent device having a structure in which a first electrode; a hole transport region; a light-emitting layer; an electron transport region and a second electrode are sequentially stacked, It includes an electron transport auxiliary layer disposed between the light-emitting layer and the electron transport region, The light-emitting layer comprises a first host, a second host, a first dopant, and a second dopant that are different from each other, and The first dopant above is a phosphorescent dopant containing platinum, and The above second dopant is a fluorescent dopant containing boron, and The superimposed emission wavelength of the first dopant and the second dopant is 10 nm or more, and The first host (H1), the second host (H2), the first dopant (D1), and the second dopant (D2) each satisfy the conditions of the following equations (i) to (iv), and (i) HOMO H1 < 5.5 eV (ii) ENTRY H2 ≥ 5.5 eV (iii) 440 ≤ λmax D1 ≤ 490 (iv) 450 ≤ λmax D2 ≤ 500 (In the above formula, HOMO H1 and HOMO H2 ε₀ is the absolute value of the HOMO energy levels of the first host material and the second host material calculated according to the Gaussian, respectively, and λmax D1 and λmax D2 is the maximum emission wavelength of the first dopant material and the second dopant material, respectively. The above electron transport region comprises an electron transport layer disposed adjacent to the above electron transport auxiliary layer, wherein The above electron transport auxiliary layer comprises a compound represented by the following chemical formula 5, and The above electron transport auxiliary layer (aETL) and the above electron transport layer (ETL) satisfy the conditions of the following equation (xi), and (xi) 0 ≤ LUMO ETL - LUMO aETL ≤ 0.2 eV (In the above equation, LUMO ETL is the absolute value of the LUMO energy level of the electron transport layer material calculated according to the Gaussian, and LUMO aETL is the absolute value of the LUMO energy levels of the electron transport auxiliary layer material calculated according to the Gaussian), The triplet energy (T1) of the first host mentioned above H1 ), triplet energy of the second host (T1 H2 ), triplet energy (T1 of the electron transport auxiliary layer aETL ), and the triplet energy (T1) of the electron transport layer ETL Organic electroluminescent device characterized by all having a voltage of 2.7 eV or higher: [Chemical Formula 5] In the above chemical formula 5, Y4 to Y6 are identical or different from each other, and each independently N or CR 31 However, at least one of Y4 to Y6 is N, and R 12 , R 31 , Ar8 and Ar9 are identical or different from each other, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group, v is an integer from 1 to 4, and L is a single bond, or C6~C 18 Selected from the group consisting of an arylene group and a heteroarylene group having 5 to 18 nuclei, A is C, Si, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group, The arylene group and heteroarylene group of the above L, and the above R 12 , R 31 , the alkyl groups, alkenyl groups, alkynyl groups, aryl groups, heteroaryl groups, aryloxy groups, alkyloxy groups, cycloalkyl groups, heterocycloalkyl groups, alkylsilyl groups, arylsilyl groups, alkylboron groups, arylboron groups, arylphosphine groups, arylphosphine oxide groups, and arylamine groups of Ar8~Ar9 and A are each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C1~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other. In paragraph 1, Singlet energy of the first host (S1 H1 ) and the singlet energy of the second host (S1 H2 Organic electroluminescent device having energies of 3.2 eV or higher. In paragraph 1, The triplet energy (T1) of the first host mentioned above H1 ) and the triplet of the second host (T1 H2 Organic electroluminescent device having energies of 2.8 eV or higher. In paragraph 1, An organic electroluminescent device in which the mixing ratio of the first host and the second host is 2:8 to 8:2 by weight. In paragraph 1, The first host is a hole-transporting compound that does not contain an electron-transporting moiety, and The above second host is an organic electroluminescent device that is an electron-transporting compound comprising at least one electron-transporting moiety. In paragraph 1, The above-mentioned first dopant is an organic electroluminescent device that is a compound represented by the following chemical formula 3: [Chemical Formula 3] In the above chemical formula 3, M is platinum, and R5 to R7 are identical or different from one another, and each independently has a single bond, O, S, C2~C 30 alkylene group of, C6~C 18 Selected from the group consisting of an arylene group and a heteroarylene group having 5 to 18 nuclei, B, C, D, and E are identical or different from one another, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 Selected from the group consisting of arylamine groups, However, at least one of B, C, D and E includes a moiety indicated by 3A below, and [Chemical Formula 3A] In the above chemical formula 3A, * indicates the position where it combines with M, r is an integer from 0 to 4, and R8 is hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It may be selected from the group consisting of arylamines or may form a condensation ring by combining with any adjacent group, wherein if r is 2 or more, multiple R8s are identical or different from each other, Ar4 and Ar5 are identical or different from each other, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring with any one selected from adjacent B, C, D, and E, and G is C6~C 60 aryl group of, C6~C 60 It is selected from the group consisting of an arylene group and a heteroarylene group having 5 to 60 nuclei, wherein when r is 2 or more, multiple Gs are identical or different from each other, B, C, D, and E of Formula 3 above, and the alkyl groups of R8, Ar4~Ar5, alkenyl, alkynyl, aryl, heteroaryl, aryloxy, alkyloxy, cycloalkyl, heterocycloalkyl, alkylsilyl, arylsilyl, alkylboron, arylboron, arylphosphine, arylphosphine oxide, and arylamine groups of Formula 3A above; and the aryl group, arylene group, and heteroarylene group of G of Formula 3A above; each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C1~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other. In paragraph 1, An organic electroluminescent device in which the second dopant has an absorption wavelength that overlaps with the emission wavelength of the first dopant by 10 nm or more. In paragraph 1, The above second dopant is an organic electroluminescent device that is a compound represented by the following chemical formula 4: [Chemical Formula 4] In the above chemical formula 4, R9 to R 11 , Ar6 and Ar7 are identical or different from each other, and each independently consists of hydrogen, deuterium, halogen, cyano group, nitro group, amino group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group, s, and t are integers from 0 to 4, respectively, and u is an integer from 0 to 3, and The above R9~R 11 , in Ar6~Ar7, alkyl groups, alkenyl groups, alkynyl groups, aryl groups, heteroaryl groups, aryloxy groups, alkyloxy groups, cycloalkyl groups, heterocycloalkyl groups, alkylsilyl groups, arylsilyl groups, alkylboron groups, arylboron groups, arylphosphine groups, arylphosphine oxide groups, and arylamine groups are; each independently deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C1~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be substituted with one or more substituents selected from the group consisting of arylamines, and if there are multiple substituents, they may be the same or different from each other. In paragraph 1, An organic electroluminescent device in which the first dopant is included in an amount of 15 weight% or less based on 100 weight% of the light-emitting layer. In paragraph 1, An organic electroluminescent device in which the second dopant is included in an amount of 4 weight% or less based on 100 weight% of the light-emitting layer. In paragraph 1, An organic electroluminescent device having a weight ratio of the total host to the total dopant in the light-emitting layer of 70:30 to 99.5:0.

5. In paragraph 1, The above electron transport auxiliary layer (aETL) is an organic electroluminescent device satisfying the conditions of the following formulas (v) to (vii): (v) HOMOLOGOUS aETL ≥ 5.5 eV (vi) LIGHT aETL ≤ 2.0 eV (vii) T1 aETL ≥ 2.8 eV (In the above formula, HOMO aETL , LUMO aETL and T1 aETL ε₀ are the absolute values ​​of the HOMO energy levels, LUMO energy levels, and triplet energies of the electron transport auxiliary layer material calculated according to the Gaussian, respectively). In paragraph 1, The above first host (H1) and the above electron transport auxiliary layer (aETL) are an organic electroluminescent device satisfying the conditions of the following formula (viii). (viii) MAN aETL - MAN H1 ≥ 0.3 eV (In the above formula, HOMO aETL silver It is the absolute value of the HOMO energy levels of the electron transport auxiliary layer material calculated according to the Gaussian, and HOMO H1 is the absolute value of the HOMO energy level of the first host material calculated according to the Gaussian. In paragraph 1, The above first host (H1) and the above electron transport auxiliary layer (aETL) are an organic electroluminescent device satisfying the conditions of the following formula (ix). (ix) LUMO aETL - LUMO H1 ≥ 0.3 eV (In the above equation, LUMO aETL silver It is the absolute value of the LUMO energy levels of the electron transport auxiliary layer material calculated according to the Gaussian, and LUMO H1 is the absolute value of the LUMO energy level of the first host material calculated according to the Gaussian. In paragraph 1, The above second host (H2) and the above electron transport auxiliary layer (aETL) are an organic electroluminescent device satisfying the conditions of the following equation (x). (x) LUMO aETL - LUMO H2 ≤ 0.2 eV (In the above equation, LUMO aETL silver It is the absolute value of the LUMO energy level of the electron transport auxiliary layer material calculated according to the Gaussian formula, and LUMO H2 is the absolute value of the LUMO energy level of the second host material calculated according to the Gaussian. In paragraph 1, The above electron transport layer (ETL) is an organic electroluminescent device satisfying the conditions of the following formulas (xii) to (xiv): (xii) MAN ETL ≥ 5.7 eV (xiii) LUMO ETL ≤ 2.1 eV (xiv) T1 ETL ≥2.8 eV (In the above formula, HOMO ETL , LUMO ETL and T1 ETL ε₀ are the absolute values ​​of the HOMO energy levels, LUMO energy levels, and triplet energies of the electron transport layer material calculated according to the Gaussian, respectively). In paragraph 1, An organic electroluminescent device in which the electron transport layer comprises a compound represented by the following chemical formula 6: [Chemical Formula 6] In the above chemical formula 6, A plurality of Zs are identical or different from one another, and each is independently CR or N, provided that at least one of the plurality of Zs is N, Ar 10 or Ar 14 They are identical or different from each other, and each independently hydrogen, deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 arylphosphine oxide group, C6~C 60 The arylamine group of, C5~C 60 It can be selected from the group consisting of an aryl heteroarylamine group and a heteroarylamine group having 5 to 60 nuclei, or can form a condensation ring by combining with any adjacent group; M is C, Si, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 The arylphosphine oxide group and C6~C 60 It can be selected from the group consisting of arylamines, or can form a condensation ring by combining with any adjacent group, R, R 13 to R 14 They are identical or different from each other, and each independently hydrogen, deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group with 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C3~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 arylphosphine oxide group, C6~C 60 The arylamine group of, C5~C 60 It can be selected from the group consisting of an aryl heteroarylamine group and a heteroarylamine group having 5 to 60 nuclei, or can form a condensation ring by combining with any adjacent group; w is an integer from 1 to 4, provided that if M is C or Si, w is 1, and N is a monocyclic or polycyclic hydrocarbon ring containing one or more heteroatoms, and L1 and L2 are identical or different from each other, and each is independently a single bond or C6~C 18 Selected from the group consisting of an arylene group and a heteroarylene group having 5 to 18 nuclei, In the above chemical formula 6, the arylene groups of L1 to L2, the heteroarylene group; and Ar 10 ~Ar 14 , R, R 13 ~R 14 , and the alkyl group, alkenyl group, alkynyl group, cycloalkyl group, heterocycloalkyl group, aryl group, heteroaryl group, alkyloxy group, aryloxy group, alkylsilyl group, arylsilyl group, alkylboron group, arylboron group, arylphosphine group, arylphosphine oxide group, arylamine group of M, and the hydrocarbon ring of N are each independently hydrogen, deuterium (D), halogen, cyano group, nitro group, C1~C 40 alkyl group of, C2~C 40 alkenyl group, C2~C 40 alkynyl group, C3~C 40 cycloalkyl group, heterocycloalkyl group having 3 to 40 nuclei, C6~C 60 aryl group, heteroaryl group having 5 to 60 nuclei, C1~C 40 alkyloxy group of, C6~C 60 The aryloxy group of, C1~C 40 alkylsilyl group of, C6~C 60 arylsilyl group of, C1~C 40 alkylboron group of, C6~C 60 arylboron group of, C6~C 60 arylphosphine group of, C6~C 60 arylphosphine oxide group, C6~C 60 The arylamine group of, C5~C 60 It may be substituted with one or more substituents selected from the group consisting of an aryl heteroarylamine group and a heteroarylamine group having 5 to 60 nuclei, and in the case where there are multiple substituents, they may be identical or different from each other. In paragraph 1, The above-mentioned electron transport area is based on the said electron transport auxiliary layer, Electron transport layer or An organic electroluminescent device comprising an electron transport layer and an electron injection layer. In paragraph 1, The above-mentioned hole transport region comprises at least one of a hole injection layer, a hole transport layer, a hole transport auxiliary layer, and a light-emitting auxiliary layer, forming an organic electroluminescent device. In paragraph 1, The above-described organic electroluminescent device comprises a plurality of light-emitting layer stacks, each including at least one light-emitting layer, and The above-mentioned at least one light-emitting layer comprises the first host, the second host, the first dopant, and the second dopant, forming an organic electroluminescent device.

Images