Boron compound and organic light-emitting devices containing them

Abstract

One embodiment of the present invention provides a boron compound. The boron compound according to an embodiment of the present invention exhibits thermally activated delayed fluorescence by having a specific framework, and an organic light-emitting device employing the same has improved efficiency.

Description

Technology Field

[0001] The present invention relates to a boron compound and an organic light-emitting device containing the same, and more specifically, to a boron compound that is a blue delayed fluorescent material containing a carbazole compound, a method for manufacturing the same, and an organic light-emitting device containing the same. Background Technology

[0002] With the recent acceleration of development in the information and communication industry, there is a demand for high-performance display devices.

[0003] These display devices can be classified into emissive and non-emissive types. Examples of emissive display devices include Cathode Ray Tubes (CRTs), Electroluminescent Displays (ELDs), Light Emitting Diodes (LEDs), and Plasma Display Panels (PDPs), while examples of non-emissive display devices include Liquid Crystal Displays (LCDs).

[0004] Generally, organic luminescence refers to the phenomenon of converting electrical energy into light energy using organic materials.

[0005] Organic light-emitting diodes (OLEDs) utilizing the organic light-emitting phenomenon typically have a structure comprising an anode, a cathode, and an organic layer between them. Here, the organic layer is often composed of a multilayer structure made of different materials to enhance the efficiency and stability of the OLED, and may consist of, for example, a hole injection layer, a hole transport layer, an emissive layer, an electron transport layer, and an electron injection layer. In the structure of such an OLED, when a voltage is applied between the two electrodes, 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, an exciton is formed, and light is emitted when this exciton falls back to the ground state.

[0006] In order to meet high performance requirements, research on the structure of organic electroluminescent devices and the materials included in each layer as described above is actively underway, and the key may be the light-emitting material included in the light-emitting layer.

[0007] Recently, following fluorescent and phosphorescent materials, there has been increasing interest in materials exhibiting Thermally Activated Delayed Fluorescence (TADF), which are evaluated as third-generation OLED materials. Unlike phosphorescent materials that convert singlet excitons into light by converting them into triplets, the aforementioned materials exhibiting Thermally Activated Delayed Fluorescence convert triplet excitons into singlets. Due to this process, they exhibit delayed fluorescence characteristics. Furthermore, because they can theoretically convert both singlet and triplet excitons into light, achieving 100% internal quantum efficiency is possible. Consequently, they are attracting attention as materials capable of overcoming the limitations of lifespan and efficiency found in blue and red phosphorescent materials, leading to active research in this area. Prior art literature

[0008] Republic of Korea Published Patent Application 10-2023-0065433 The problem to be solved

[0009] The present invention provides two boron compounds with high applicability and synthesis efficiency as a method to solve the problems of the aforementioned prior art.

[0010] In addition, a method for simply preparing the two boron compounds above is provided according to temperature control within an appropriate range.

[0011] The technical problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art to which the present invention belongs from the description below. means of solving the problem

[0012] To achieve the above technical problem, one embodiment of the present invention provides a boron compound.

[0013] A boron compound according to one embodiment of the present invention is characterized by being represented by the following chemical formula 1.

[0014] [Chemical Formula 1]

[0015]

[0016] In the above chemical formula 1,

[0017] X1 and X2 are each independently N or P, and

[0018] R1 to R6 are the same or different from one another and are each independently selected from the group consisting of hydrogen; deuterium; halogen; straight-chain or branched-chain alkyl of C1 to C60; straight-chain or branched-chain alkenyl of C2 to C60; straight-chain or branched-chain alkynyl of C2 to C60; straight-chain or branched-chain alkoxy of C1 to C60; monocyclic or polycyclic cycloalkyl of C3 to C60; monocyclic or polycyclic heterocycloalkyl of C2 to C60; monocyclic or polycyclic aryl of C6 to C60; and monocyclic or polycyclic heteroaryl of C2 to C60.

[0019] In an embodiment of the present invention, in Formula 1, R1 to R4 are the same or different from each other, and each independently an aryl of C6 to C30; or a heteroaryl of C3 to C30; and

[0020] R5 and R6 may be boron compounds characterized by being the same or different from each other and each independently selected from the group consisting of hydrogen; deuterium; halogen; cyano; C1 to C30 alkyl; C1 to C30 alkoxy; C3 to C30 cycloalkyl; C3 to C30 heterocycloalkyl; C6 to C30 aryl; and C3 to C30 heteroaryl.

[0021] In an embodiment of the present invention, the boron compound is characterized in that the formula 1 is selected from the following compound group 1:

[0022] [Compound Group 1]

[0023]

[0024]

[0025]

[0027] To achieve the above technical problem, another embodiment of the present invention provides a boron compound.

[0028] A boron compound according to one embodiment of the present invention is characterized by being represented by the following chemical formula 2.

[0029] [Chemical Formula 2]

[0030]

[0031] In the above chemical formula 2,

[0032] X3 and X4 are each independently N or P, and

[0033] R7 to R 12The elements are the same or different from one another and are each independently selected from the group consisting of hydrogen; deuterium; halogen; straight-chain or branched-chain alkyl of C1 to C60; straight-chain or branched-chain alkenyl of C2 to C60; straight-chain or branched-chain alkynyl of C2 to C60; straight-chain or branched-chain alkoxy of C1 to C60; monocyclic or polycyclic cycloalkyl of C3 to C60; monocyclic or polycyclic heterocycloalkyl of C2 to C60; monocyclic or polycyclic aryl of C6 to C60; and monocyclic or polycyclic heteroaryl of C2 to C60.

[0034] In an embodiment of the present invention, in the above chemical formula 2, R7 to R 10 are the same or different from each other, and each independently is a C6 to C30 aryl; or a C3 to C30 heteroaryl; and R 11 and R 12 The boron compound may be characterized by being the same or different from one another and each independently selected from the group consisting of hydrogen; deuterium; halogen; cyano; C1 to C30 alkyl; C1 to C30 alkoxy; C3 to C30 cycloalkyl; C3 to C30 heterocycloalkyl; C6 to C30 aryl; and C3 to C30 heteroaryl.

[0035] In an embodiment of the present invention, the chemical formula 2 may be a boron compound characterized by being selected from the following compound group 2.

[0036] [Compound Group 2]

[0037]

[0038]

[0039]

[0041] To achieve the above technical problem, another embodiment of the present invention provides an organic light-emitting element.

[0042] An organic light-emitting device according to one embodiment of the present invention is an organic electroluminescent device comprising a first electrode, a second electrode, and one or more organic layers disposed between the first electrode and the second electrode, wherein one or more of the organic layers comprise a compound of [Chemical Formula 1] or [Chemical Formula 2] according to claim 1 or 4.

[0043] In an embodiment of the present invention, the compound of [Chemical Formula 1] or [Chemical Formula 2] may be an organic light-emitting device characterized by being used as a host compound within the organic layer.

[0044] In an embodiment of the present invention, the organic layer comprising the compound of [Chemical Formula 1] or [Chemical Formula 2] may be an organic light-emitting element that emits blue light. Effects of the invention

[0045] According to an embodiment of the present invention, a boron compound containing a carbazole compound has high triplet energy and stability, and can exhibit thermally activated delayed fluorescence.

[0046] In addition, an organic electric field device comprising a boron compound according to one embodiment of the present invention may have the effect of improved color purity, lifespan, and increased reaction efficiency.

[0047] Additionally, the method for manufacturing a boron compound according to one embodiment of the present invention has the advantage of synthesizing boron in different directions depending on temperature control, thereby allowing two types of blue delayed fluorescent materials to be obtained simply.

[0048] The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description of the invention or the claims. Brief explanation of the drawing

[0049] FIG. 1 is a conceptual diagram showing a multilayer organic light-emitting diode according to one embodiment of the present invention. FIG. 2 is a diagram showing the NMR spectrum of a boron compound having the structure of Formula 3, which is one manufacturing example of the present invention. Figure 3 is a diagram showing the NMR spectrum of a boron compound having the structure of Formula 11, which is a manufacturing example of the present invention. Figure 4 is a diagram showing the NMR spectrum of a boron compound having the structure of Formula 3 and Formula 11, which is a manufacturing example of the present invention. Specific details for implementing the invention

[0050] The present invention will be described below with reference to the attached drawings. However, the present invention may be implemented in various different forms and is therefore not limited to the embodiments described herein. Furthermore, in order to clearly explain the present invention in the drawings, parts unrelated to the explanation have been omitted, and similar parts throughout the specification have been given similar reference numerals.

[0051] Throughout the specification, when it is stated that a part is "connected (connected, in contact, combined)" with another part, this includes not only cases where they are "directly connected," but also cases where they are "indirectly connected" with other members interposed between them. Furthermore, when it is stated that a part "includes" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but rather allows for the inclusion of additional components.

[0052] The terms used herein are merely for describing specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “comprising” or “having” are intended to indicate the presence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0053] As used herein, the term “alkyl” means a saturated straight-chain or branched non-cyclic hydrocarbon having 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms (where the number of carbon atoms is not particularly limited). Representative saturated straight-chain alkyls include -methyl, -ethyl, -n-propyl, -n-butyl, -n-pentyl, -n-hexyl, -n-heptyl, -n-octyl, -n-nonyl, and -n-decyl, while saturated branched alkyls include -isopropyl, -sec-butyl, -isobutyl, -tert-butyl, isopentyl, 2-methylhexyl, 3-methylbutyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 2-methylhexyl, 3-methylhexyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, 2,3-dimethylbutyl, 2,3-dimethylpentyl, 2,4-dimethylpentyl, It includes 2,3-dimethylhexyl, 2,4-dimethylhexyl, 2,5-dimethylhexyl, 2,2-dimethylpentyl, 2,2-dimethylhexyl, 3,3-dimethylpentyl, 3,3-dimethylhexyl, 4,4-dimethylhexyl, 2-ethylpentyl, 3-ethylpentyl, 2-diethylhexyl, 3-ethylhexyl, 4-ethylhexyl, 2-methyl-2-ethylpentyl, 2-methyl-3-ethylpentyl, 2-methyl-4-ethylpentyl, 2-methyl-2-ethylhexyl, 2-methyl-3-ethylhexyl, 2-methyl-4-ethylhexyl, 2,2-diethylpentyl, 3,3-diethylhexyl, 2,2-diethylhexyl, and 3,3-diethylhexyl.

[0054] In this specification, "C 1-5 When written as ", this means that the number of carbon atoms is 1 to 5. For example, C 1-5 Alkyl means an alkyl having 1 to 5 carbon atoms.

[0055] The terms “halogen” and “halo” as used in this specification mean fluorine, chlorine, bromine, or iodine.

[0056] As used in this specification, the term “alkoxy” means -O-(alkyl), including -OCH3, -OCH2CH3, -O(CH2)2CH3, -O(CH2)3CH3, -O(CH2)4CH3, -O(CH2)5CH3, and similar ones, wherein alkyl is as defined above.

[0057] As used herein, the term "aryl" refers to a carbon-ring aromatic group containing 5 to 10 ring atoms.

[0058] Examples of targets include, but are not limited to, phenyl, tolyl, xylyl, naphthyl, tetrahydronaphthyl, anthracenyl, fluorenyl, indenyl, azulenyl, etc. The carbon ring aromatic group may be optionally substituted.

[0059] As used herein, the term "cycloalkyl" means a monocyclic or polycyclic saturated ring having carbon and hydrogen atoms and not having carbon-carbon multiple bonds. Examples of cycloalkyl groups include, but are not limited to, (C3-C10)cycloalkyls (e.g., cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl). Cycloalkyl groups may be optionally substituted. In one embodiment, the cycloalkyl group is a monocyclic or bicyclic ring.

[0060] As used herein, the term “heterocycloalkyl” refers to a stable 3- to 18-membered saturated or partially unsaturated radical composed of 2 to 12, preferably 2 to 10, carbon atoms and 1 to 6 heteroatoms selected from the group consisting of nitrogen, oxygen, and sulfur, e.g., 1 to 5 heteroatoms, 1 to 4 heteroatoms, 1 to 3 heteroatoms, or 1 to 2 heteroatoms. Exemplary heterocycloalkyls include, without limitation, stable 3-15 member saturated or partially unsaturated radicals, stable 3-12 member saturated or partially unsaturated radicals, stable 3-9 member saturated or partially unsaturated radicals, stable 8 member saturated or partially unsaturated radicals, stable 7 member saturated or partially unsaturated radicals, stable 6 member saturated or partially unsaturated radicals, or stable 5 member saturated or partially unsaturated radicals.

[0061] As used herein, “heteroaryl” is an aromatic heterocycle ring of 5 to 10 members comprising at least one carbon atom selected from the group consisting of nitrogen, oxygen and sulfur, and having at least one heteroatom selected from the group consisting of mono- and bicyclic ring systems. Representative heteroaryls are triazoleyl, tetrazolyl, oxadiazoleyl, pyridyl, furyl, benzofuranyl, thiophenyl, benzothiophenyl, quinolinyl, pyrrolyl, indoleyl, oxazolyl, benzoxazolyl, imidazoleyl, benzimidazoleyl, thiazolyl, benzothiazoleyl, isoxazolyl, pyrazolyl, isothiazoleyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, cinnolinyl, phthalazinyl, quinazolinyl, pyrimidyl, oxetanil, azefinil, piperazinyl, morpholinyl, dioxanil, tiethanil, and oxazolyl. The heteroaryl group can be monocyclic or bicyclic. Heteroaryl may be used interchangeably with the terms heteroaryl ring, heteroaryl group, or heteroaromatic, all of which may include an arbitrarily substituted ring.

[0062] As used herein, the term “monoalkylamino” means -NH(alkyl), including -NHCH3, -NHCH2CH3, -NH(CH2)2CH3, -NH(CH2)3CH3, -NH(CH2)4CH3, -NH(CH2)5CH3, and similar ones, wherein alkyl is as defined above.

[0063] As used herein, the term “dialkylamino” means -N(alkyl)(alkyl), including -N(CH3)2, -N(CH2CH3)2, -N((CH2)2CH3)2, -N(CH3)(CH2CH3), and similar ones, wherein each alkyl is an alkyl defined above independently of each other.

[0065] The present invention provides a boron compound comprising boron and a carbazole compound, and provides two types of boron compounds having a symmetrical structure and an asymmetrical structure.

[0066] The boron compound of the present invention has excellent thermal stability and a small difference between the singlet energy level and the triplet energy level, thereby improving the optical properties of an organic light-emitting device employing it, and in particular, can improve the stability, luminous efficiency, and color purity of said device.

[0067] In addition, the boron compounds of the present invention have the advantage of synthesizing boron in different directions by simply controlling only the temperature under the same reaction process, thereby allowing two types of blue delayed fluorescent materials to be obtained simply.

[0069] Embodiments of the present invention will be described in detail below with reference to the attached drawings.

[0071] A boron compound according to one embodiment of the present invention is described.

[0072] A boron compound according to one embodiment of the present invention is characterized by being represented by the following chemical formula 1.

[0073] [Chemical Formula 1]

[0074]

[0075] In the above chemical formula 1,

[0076] X1 and X2 are each independently N or P, and

[0077] R1 to R6 are the same or different from one another and are each independently selected from the group consisting of hydrogen; deuterium; halogen; straight-chain or branched-chain alkyl of C1 to C60; straight-chain or branched-chain alkenyl of C2 to C60; straight-chain or branched-chain alkynyl of C2 to C60; straight-chain or branched-chain alkoxy of C1 to C60; monocyclic or polycyclic cycloalkyl of C3 to C60; monocyclic or polycyclic heterocycloalkyl of C2 to C60; monocyclic or polycyclic aryl of C6 to C60; and monocyclic or polycyclic heteroaryl of C2 to C60.

[0078] A boron compound according to one embodiment of the present invention has excellent thermal stability and is a polycyclic aromatic compound containing boron, having a large HOMO-LUMO gap and a small difference between the singlet energy level and the triplet energy level, so an organic electronic device employing it can achieve high efficiency.

[0079] A boron compound according to one embodiment of the present invention includes a carbazole compound at a specific site of the boron compound as in Chemical Formula 1, and corresponds to a symmetrical structure in which the left and right sides of the backbone are symmetrical.

[0080] In this case, in the above chemical formula 1, preferably R1 to R4 are the same or different from each other and are each independently an aryl of C6 to C30; or a heteroaryl of C3 to C30, and

[0081] R5 and R6 may be boron compounds characterized by being the same or different from each other and each independently selected from the group consisting of hydrogen; deuterium; halogen; cyano; C1 to C30 alkyl; C1 to C30 alkoxy; C3 to C30 cycloalkyl; C3 to C30 heterocycloalkyl; C6 to C30 aryl; and C3 to C30 heteroaryl.

[0082] Specifically, Formula 1 according to one embodiment of the present invention may be a boron compound selected from compound group 1, but is not limited thereto.

[0083] [Compound Group 1]

[0084]

[0085]

[0086]

[0088] A boron compound according to another embodiment of the present invention is described.

[0089] A boron compound according to another embodiment of the present invention is characterized by being represented by the following chemical formula 2.

[0090] [Chemical Formula 2]

[0091]

[0092] In the above chemical formula 2,

[0093] X3 and X4 are each independently N or P, and

[0094] R7 to R 12 The elements are the same or different from one another and are each independently selected from the group consisting of hydrogen; deuterium; halogen; straight-chain or branched-chain alkyl of C1 to C60; straight-chain or branched-chain alkenyl of C2 to C60; straight-chain or branched-chain alkynyl of C2 to C60; straight-chain or branched-chain alkoxy of C1 to C60; monocyclic or polycyclic cycloalkyl of C3 to C60; monocyclic or polycyclic heterocycloalkyl of C2 to C60; monocyclic or polycyclic aryl of C6 to C60; and monocyclic or polycyclic heteroaryl of C2 to C60.

[0095] A boron compound according to another embodiment of the present invention has excellent thermal stability and is a polycyclic aromatic compound containing boron, having a large HOMO-LUMO gap and a small difference between the singlet energy level and the triplet energy level, so an organic electronic device employing it can achieve high efficiency.

[0096] A boron compound according to one embodiment of the present invention includes a carbazole compound at a specific site of the boron compound as in Chemical Formula 2 above, and unlike the boron compound of Chemical Formula 1 above, it corresponds to an asymmetric structure in which the left and right sides of the skeleton are asymmetric.

[0097] At this time, in the above chemical formula 2, R7 to R 10 are the same or different from each other, and each independently is a C6 to C30 aryl; or a C3 to C30 heteroaryl; and R 11 and R 12 The boron compound may be characterized by being the same or different from one another and each independently selected from the group consisting of hydrogen; deuterium; halogen; cyano; C1 to C30 alkyl; C1 to C30 alkoxy; C3 to C30 cycloalkyl; C3 to C30 heterocycloalkyl; C6 to C30 aryl; and C3 to C30 heteroaryl.

[0098] In an embodiment of the present invention, the chemical formula 2 may be a boron compound characterized by being selected from the following compound group 2.

[0099] [Compound Group 2]

[0100]

[0101]

[0102]

[0104] An organic light-emitting element according to another embodiment of the present invention is described.

[0105] An organic light-emitting device according to one embodiment of the present invention is an organic electroluminescent device comprising a first electrode, a second electrode, and one or more organic layers disposed between the first electrode and the second electrode, wherein one or more of the organic layers comprise a compound of [Chemical Formula 1] or [Chemical Formula 2].

[0106] That is, an organic light-emitting device according to one embodiment of the present invention may be formed with a structure including a first electrode, a second electrode, and an organic layer disposed between them, and may be manufactured using conventional manufacturing methods and materials for devices, except that a compound of [Chemical Formula 1] or [Chemical Formula 2] according to the present invention is used in the organic layer of the device.

[0107] The organic layer of the organic light-emitting device according to the present invention may be formed as a single layer structure, but may be formed as a multilayer structure in which two or more organic layers are stacked. For example, it may have a structure including a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, etc. However, it is not limited thereto and may include a smaller or larger number of organic layers.

[0108] Accordingly, in the organic light-emitting device of the present invention, the organic layer may include one or more layers among a hole injection layer, a hole transport layer, and a layer that performs hole injection and hole transport simultaneously, and one or more layers among the layers may include a compound represented by [Chemical Formula 1] or [Chemical Formula 2].

[0109] In addition, in the organic light-emitting device of the present invention, the organic layer may include one or more layers among an electron injection layer, an electron transport layer, and a layer that performs electron injection and electron transport simultaneously, and one or more layers among the layers may include a compound represented by [Chemical Formula 1] or [Chemical Formula 2].

[0110] Additionally, the organic layer may include a light-emitting layer, and the light-emitting layer may include a compound represented by [Chemical Formula 1] or [Chemical Formula 2]. Here, the compound represented by [Chemical Formula 1] or [Chemical Formula 2] may be included as a host material within the light-emitting layer and may be a layer that emits thermally active delayed fluorescence. When the compound represented by [Chemical Formula 1] is included as a host material within the light-emitting layer, the light-emitting layer may further include one or more dopant compounds. Thus, in the present invention, a dopant material may be used in addition to a host in the light-emitting layer. When the light-emitting layer includes a host and a dopant, the content of the dopant may typically be selected in the range of about 0.01 to about 20 parts by weight based on about 100 parts by weight of the host.

[0111] In addition, in such a multilayer organic layer, the compound represented by [Chemical Formula 1] may be included in a light-emitting layer, a layer that simultaneously performs hole injection / hole transport and light emission, a layer that simultaneously performs hole transport and light emission, or a layer that simultaneously performs electron transport and light emission.

[0112] FIG. 1 is a conceptual diagram showing an organic electroluminescent device according to the present invention. The organic electroluminescent device according to the present invention includes an anode (20), a hole transport layer (40), an organic light-emitting layer (50), an electron transport layer (60), and a cathode (80). If necessary, it may further include a hole injection layer (30) and an electron injection layer (70). Additionally, it may be possible to further form one or two intermediate layers, or to further form a hole blocking layer or an electron blocking layer, and may further include an organic layer having various functions depending on the characteristics of the device.

[0113] The organic electroluminescent element according to the present invention can be used in a device selected from a flat panel display device, a flexible display device, a monochromatic or white flat panel lighting device and a monochromatic or white flexible lighting device.

[0115] The present invention will be explained in more detail below through manufacturing examples, comparative examples, and experimental examples. However, the present invention is not limited to the following manufacturing examples and experimental examples.

[0117] Preparation Example 1: Synthesis of DABNA-Cz (Green, Chemical Formula 3)

[0118] [Reaction Equation 1]

[0119]

[0120] [Reaction Equation 1-1]

[0121]

[0122] 4-bromo-1,1'-biphenyl (25.0 g, 107.24mmol), dimethylaniline (12.98 g, 107.24 mmol), Sodium tert-butoxide (20.6 g, 214.5mmol), Tri-tert-butylphosphine 2.5M (1.71 ml, 4.29mmol), Dissolve Pd2(dba)3 (0.98 g, 10.7 mmol) in 250 ml of Toluene.

[0123] The mixture was heated and stirred at 120°C under a nitrogen atmosphere for 8 hours. After cooling to room temperature, the reaction mixture was poured into water, the precipitate was filtered, and washed with water. The crude product was extracted with toluene. The organic layer was dried over MgSO4 and filtered through silica gel. After evaporating the solvent, the product was washed with methanol to obtain a white solid. (22.0 g, 75% yield)

[0125] [Reaction Equation 1-2]

[0126]

[0127] Dissolve 1,3-dibromo-5-fluorobenzene (25.0 g, 98.5 mmol), Carbazole (11.52 g, 95.5mmol), and Cesium carbonate (35.3 g, 108.3 mmol) in 150 ml of N-Methyl-2-pyrrolidone.

[0128] The mixture was heated and stirred at 100°C under a nitrogen atmosphere for 10 hours. After cooling to room temperature, the reaction mixture was poured into water, the precipitate was filtered, and washed with water. The crude product was extracted with MC. The organic layer was dried over MgSO4 and filtered through silica gel. After evaporating the solvent, the product was washed with methanol to obtain a white solid. (32.3 g, 81.8% yield)

[0130] [Reaction Equation 1-3]

[0131]

[0132] Compound (1) (15.0 g, 37.0 mmol), compound (2) (20.0 g, 73.15 mmol), sodium tert-butoxide (21.75 g, 226.36 mmol), tri-tert-butylphosphine 2.5M (1.46 ml, 3.65 mmol), and Pd2(dba)3 (1.3 g, 1.46 mmol) are dissolved in 300 ml of toluene.

[0133] The mixture was heated and stirred at 120°C under a nitrogen atmosphere for 8 hours. After cooling to room temperature, the reaction mixture was poured into water, the precipitate was filtered, and washed with water. The crude product was extracted with toluene. The organic layer was dried over MgSO4 and filtered through silica gel. After evaporating the solvent, the product was washed with methanol to obtain a white solid. (21.4 g, 72.8% yield) 1H NMR

[0135] [Reaction Equation 1-4]

[0136]

[0137] Compound (3) (3 g, mmol) is dissolved in 40 ml of 1,2-Dichlorobenzene under a nitrogen atmosphere by stirring.

[0138] After adding BBr3 dropwise to the mixture, heat and stir at 200°C for 24 hours. Once the reaction is finished, cool to 0°C and observe the color change while adding N-ethyldiisopropylamine dropwise. When it is confirmed that no further exothermic reaction occurs, filter the reaction mixture with toluene and purify the product by column chromatography (Hex:Tol = 5:1).

[0139] After purification, the product was recrystallized with toluene to obtain a yellow solid. (1.2 g, 39.8% yield)

[0140] The compound (4) produced corresponds to a symmetric boron compound identical to Formula 3, which is an embodiment of the present invention, and is named DABNA-cz(Green) below.

[0142] Preparation Example 2: Synthesis of DABNA-Cz(Blue, Chemical Formula 11)

[0143] [Reaction Equation 2]

[0145]

[0146] Compound (3) (3 g, mmol) obtained from reaction scheme 1-3 of Preparation Example 1 above is dissolved in 40 ml of toluene under a nitrogen atmosphere by stirring.

[0147] After adding BBr3 dropwise to the mixture, the mixture is heated and stirred at 120°C for 5 days. After the reaction is finished, the mixture is cooled to 0°C, and N-ethyldiisopropylamine is added dropwise while observing the color change. Once it is confirmed that no further exothermic reaction occurs, the reaction mixture is filtered using toluene, and the product is purified by column chromatography (Hex:Tol = 5:1).

[0148] After purification, the product was recrystallized with toluene and methanol to obtain a yellow solid. (0.9 g, 29.8% yield)

[0149] The compound (5) produced corresponds to an asymmetric boron compound identical to Formula 11, which is an embodiment of the present invention, and is named DABNA-cz(Blue) below.

[0151] That is, as in Preparation Examples 1 and 2 above, the present invention has the feature of being able to control the synthesis of a boron compound having a symmetric structure of Formula 3 or an asymmetric structure of Formula 11 by changing the time and temperature conditions of the reaction under the same reaction process.

[0152] Specifically, when the reaction is carried out at a high temperature (200°C) as in [Reaction Scheme 1-4] above, a symmetric boron compound having the structure of Chemical Formula 3 described above can be the major product.

[0153] Conversely, when the reaction is carried out at a low temperature (120°C) as in [Reaction Scheme 2] above, an asymmetric boron compound having the structure of Chemical Formula 11 described above can be the major product compound.

[0154] This is because, due to the reactivity of the electrophilic substitution of the aromatic substituents of the substituted amine and the electrophilic substitution of the carbazole, depending on the temperature of the reaction, the reaction between the aromatic substituents of the amine or the reaction between the aromatic substituents of the amine and the carbazole proceeds, and consequently, a product in which boron is symmetrically or asymmetrically substituted is formed.

[0156] Experimental Example 1: NMR Spectrum

[0157] NMR spectrum analysis was performed on the compounds of Preparation Examples 1 and 2 prepared.

[0158] FIG. 2 is a diagram showing the NMR spectrum of a boron compound having the structure of Formula 3, which is one manufacturing example of the present invention.

[0159] Figure 3 is a diagram showing the NMR spectrum of a boron compound having the structure of Formula 11, which is a manufacturing example of the present invention.

[0160] Figure 4 is a diagram showing the difference in NMR spectra of boron compounds having the structures of Formula 3 and Formula 11, which are one example of the preparation of the present invention.

[0162] As shown in FIGS. 2 and FIGS. 4 above, it can be confirmed that the compound prepared by the above Preparation Example 1 is a compound having the structure of the above Chemical Formula 3.

[0164] As shown in FIGS. 3 and 4 above, it can be confirmed that the compound prepared by Preparation Example 2 is a compound having the structure of Formula 11.

[0166] Experimental Example 2: Physical Property Test

[0167] The compounds of Preparation Examples 1 and 2 were prepared in sol form, and physical property analysis was performed.

[0168] [Chemical Formula 3]

[0169]

[0171]

[0172]

[0173]

[0175] [Chemical Formula 11]

[0176]

[0178]

[0180]

[0182]

[0184] Compound UV (THF) (nm) PL (Tol) (nm) PL low (THF) (nm) FWHM (nm) S 1, onset T 1, onset E ST E g (optical) (eV) HOMO (eV) LOMO (eV) PLQY (%) DABNA―Cz (Green) 461 470 498 31 2.47 2.34 0.13 2.83 -5.51 2.68 50.86 DABNA―Fused Cz (Blue) 447 461 491 29 2.83 2.62 0.21 2.67 -5.40 2.73 64.60

[0185] DABNA―Cz (Green) in is This is a physical property analysis table showing the UV, PL, CV, and PLQY values ​​of a boron compound having the structure of Formula 3, which is one manufacturing example of the present invention.

[0186] DABNA―Fused Cz (Blue) in is This is a physical property analysis table showing the UV, PL, CV, and PLQY values ​​of a boron compound having the structure of Formula 11, which is one manufacturing example of the present invention.

[0188] As shown in above, it can be confirmed that the compounds Formula 3 and Formula 11 prepared by Preparation Example 1 and Preparation Example 2 each have different physical properties.

[0189] The structure of Formula 3, a symmetrically substituted product, exhibited an emission wavelength of 470 nm, whereas the asymmetric compound of Formula 11 showed an emission wavelength of 461 nm. Additionally, the symmetric compound had a relatively small ΔE ST While it had a deep HOMO level, it had asymmetric chemical formula 11, with an emission wavelength of 461 nm and a narrow full width at half maximum.

[0191] The foregoing description of the present invention is for illustrative purposes only, and those skilled in the art will understand that other specific forms can be easily modified without altering the technical spirit or essential features of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single unit may be implemented in a distributed manner, and components described as distributed may likewise be implemented in a combined form.

[0192] The scope of the present invention is defined by the claims set forth below, and all modifications or variations derived from the meaning and scope of the claims and equivalent concepts thereof should be interpreted as being included within the scope of the present invention.

Claims

Claim 1 delete Claim 2 delete Claim 3 delete Claim 4 Boron compound characterized by being selected from the following compound group 2: [Compound group 2] Claim 5 delete Claim 6 delete Claim 7 An organic electroluminescent device comprising a first electrode, a second electrode, and one or more organic layers disposed between the first electrode and the second electrode, wherein one or more of the organic layers comprise a compound according to claim 4. Claim 8 An organic light-emitting device according to claim 7, characterized in that the compound is used as a host compound within the organic layer. Claim 9 In claim 7, the organic light-emitting device wherein the organic layer containing the compound emits blue light.

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