KR102301612B1 - An electroluminescent compound and an electroluminescent device comprising the same - Google Patents

Abstract

The present invention relates to a novel organic light emitting compound represented by chemical formula I that is employed in a light efficiency improving layer provided in an organic light emitting device to realize light emitting characteristics such as low voltage driving and excellent light emitting efficiency of a device, and an organic light emitting device including the same.

Description

An organic light emitting compound and an organic light emitting device comprising the same

The present invention relates to an organic light emitting compound, and more particularly, to an organic light emitting compound, characterized in that it is employed as a material for a light efficiency improving layer (Capping layer) provided in an organic light emitting device, and low voltage driving and excellent luminous efficiency of the device by employing the same It relates to an organic light emitting device with significantly improved light emitting characteristics, such as.

Organic light emitting devices can be formed on transparent substrates as well as low voltage driving of 10 V or less compared to plasma display panels or inorganic electroluminescence (EL) displays, and consumes relatively little power. , has the advantage of excellent color, and can represent three colors of green, blue, and red, and has recently become a subject of much interest as a next-generation display device.

However, in order for such an organic light emitting device to exhibit the above characteristics, a hole injection material, a hole transport material, a light emitting material, an electron transport material, an electron injection material, etc. However, the development of a stable and efficient organic material layer material for an organic light emitting device has not yet been sufficiently developed.

Therefore, in order to realize a more stable organic light emitting device, and to achieve high efficiency, long lifespan, and large size of the device, additional improvements are required in terms of efficiency and lifespan characteristics. It is desperately needed.

In this regard, recently, with respect to the material of the hole transport layer in the structure of the organic light emitting device, research for improving the conductivity of the existing organic material has been actively conducted.

In addition, recently, as well as research on improving the characteristics of organic light emitting devices by changing the performance of each organic layer material, color purity improvement and luminous efficiency enhancement technology by the optical thickness optimized between the anode and the cathode have been developed. It has been focused on as one of the important factors for improving the performance, and as an example of this method, an increase in light efficiency and excellent color purity are achieved by using a capping layer on an electrode.

Accordingly, the present invention is to provide a novel organic light emitting compound capable of implementing excellent light emitting characteristics such as low voltage driving and improved light emitting efficiency of the device by being employed in the light efficiency improving layer provided in the organic light emitting device and an organic light emitting device including the same. .

In order to solve the above problems, the present invention provides any one organic light emitting compound selected from the compounds represented by the following [Formula I].

[Formula Ⅰ]

Characteristic structures of the [Formula I] and X and Ar ₁ to Ar ₄ will be described later.

In addition, the present invention is an organic light emitting device comprising a first electrode, a second electrode, and one or more organic layers disposed between the first electrode and the second electrode, wherein the first electrode and the upper or lower portion of the second electrode An organic light-emitting device comprising an organic light-emitting compound represented by the [Formula I] in the light-efficiency improving layer while further comprising a light efficiency improving layer (Capping layer) formed on at least one side opposite to the organic layer among do.

When the organic light emitting compound according to the present invention is employed as a material for the light efficiency improvement layer provided in the organic light emitting device, it can realize light emitting characteristics such as low voltage driving and excellent light emitting efficiency of the device, and thus can be usefully used in various display devices.

1 is a representative view showing the structure of an organic light emitting compound according to the present invention.

Hereinafter, the present invention will be described in more detail.

The present invention relates to an organic light emitting compound represented by the following [Formula I], which is employed in a light efficiency improving layer provided in an organic light emitting device to obtain light emitting characteristics such as low voltage driving and excellent light emission efficiency of the device, and is structurally dibenzo It is characterized in that it has furan or dibenzothiophene as its backbone, and a substituted or unsubstituted alkyl group, cycloalkyl group, aryl group, etc. is introduced at the 2nd, 4th, 6th, or 8th carbon positions.

[Formula Ⅰ]

In the [Formula I],

X is O or S, Ar _{1 To} Ar ₄ are the same as or different from each other, and each independently a substituted or unsubstituted C 1 to C 20 alkyl group, a substituted or unsubstituted C 3 to C 20 cycloalkyl group, and a substituted or unsubstituted Any one selected from a cyclic aryl group having 6 to 30 carbon atoms.

In addition, in the _{definition of Ar 1} to Ar ₄ , 'substituted or unsubstituted' means deuterium, a halogen group, a cyano group, a nitro group, a hydroxyl group, a silyl group, an alkyl group, a cycloalkyl group, an alkoxy group, and an aryl group. It means that it is substituted with one or two or more selected substituents, or is substituted with a substituent to which two or more of the substituents are connected, or does not have any substituents, and specific structures thereof can be found in the structures of specific compounds to be described later.

For specific examples, the substituted aryl group includes a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, a pyrenyl group, a phenanthrenyl group, a peryleneyl group, a tetracenyl group, an anthracenyl group, etc. It means that it is further substituted or is substituted with a substituent in which two or more of the substituents are connected.

In the present invention, examples of the substituents will be described in detail below, but the present invention is not limited thereto.

In the present invention, the alkyl group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 1 to 20. Specific examples include methyl group, ethyl group, propyl group, n-propyl group, isopropyl group, butyl group, n-butyl group, isobutyl group, tert-butyl group, sec-butyl group, 1-methyl-butyl group, 1- Ethyl-butyl group, pentyl group, n-pentyl group, isopentyl group, neopentyl group, tert-pentyl group, hexyl group, n-hexyl group, 1-methylpentyl group, 2-methylpentyl group, 4-methyl- 2-pentyl group, 3,3-dimethylbutyl group, 2-ethylbutyl group, heptyl group, n-heptyl group, 1-methylhexyl group, cyclopentylmethyl group, cyclohexylmethyl group, octyl group, n-octyl group, tert -Octyl group, 1-methylheptyl group, 2-ethylhexyl group, 2-propylpentyl group, n-nonyl group, 2,2-dimethylheptyl group, 1-ethyl-propyl group, 1,1-dimethyl-propyl group , isohexyl group, 2-methylpentyl group, 4-methylhexyl group, 5-methylhexyl group, and the like, but is not limited thereto.

In the present invention, the aryl group may be monocyclic or polycyclic, and the number of carbon atoms is not particularly limited, but is preferably 6 to 30. Examples of the monocyclic aryl group include a phenyl group, a biphenyl group, a terphenyl group, and a stilbene group, and examples of the polycyclic aryl group include a naphthyl group, anthracenyl group, phenanthrenyl group, pyrenyl group, perylenyl group, tetracenyl group , chrysenyl group, fluorenyl group, acenaphthacenyl group, triphenylene group, fluoranthrene group, etc., but the scope of the present invention is not limited to these examples.

,

등이 있다.In the present invention, the fluorenyl group is a structure in which two ring organic compounds are connected through one atom, for example,

,

etc.

,

등이 있다.In the present invention, the fluorenyl group includes a structure of an open fluorenyl group, wherein the open fluorenyl group is a structure in which one ring compound is disconnected in a structure in which two ring organic compounds are connected through one atom. , for example

,

etc.

In the present invention, cycloalkyl groups refer to monocyclic, polycyclic and spiro alkyl radicals and include, but are not limited to, cyclopropyl, cyclopentyl, cyclohexyl, bicycloheptyl, spirodecyl, spirodecyl, adamantyl, and the like. , the cycloalkyl group may be optionally substituted.

In the present invention, the silyl group specifically includes a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, a vinyldimethylsilyl group, a propyldimethylsilyl group, a triphenylsilyl group, a diphenylsilyl group, a phenylsilyl group, and the like. However, the present invention is not limited thereto.

Specific examples of the halogen group as a substituent used in the present invention include fluorine (F), chlorine (Cl), bromine (Br), and the like.

In the present invention, the alkoxy group may be straight-chain or branched. Although carbon number of an alkoxy group is not specifically limited, It is preferable that it is a range which does not give steric hindrance that it is 1-20. Specifically, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, i-propyloxy group, n-butoxy group, isobutoxy group, tert-butoxy group, sec-butoxy group, n-pentyloxy group , neopentyloxy group, isopentyloxy group, n-hexyloxy group, 3,3-dimethylbutyloxy group, 2-ethylbutyloxy group, n-octyloxy group, n-nonyloxy group, n-decyloxy group , a benzyloxy group, a p-methylbenzyloxy group, etc., but is not limited thereto.

The organic light emitting compound according to the present invention represented by the above [Formula I] can be used as various organic material layers in an organic light emitting device due to its structural specificity, and more specifically, it can be used as a material for the light emitting layer, hole transport layer or light efficiency improvement layer in the organic material layer. have.

Preferred examples of the organic light emitting compound represented by [Formula I] according to the present invention include the following compounds, but is not limited thereto.

As such, the organic light emitting compound according to the present invention can synthesize an organic light emitting compound having various characteristics using a characteristic skeleton exhibiting unique properties and a moiety having intrinsic properties introduced thereto, As a result, when the organic light emitting compound according to the present invention is applied to various organic material layer materials such as a light emitting layer, a light efficiency improving layer, a hole transport layer, an electron transport layer, an electron blocking layer, a hole blocking layer, etc. can

In addition, the compound of the present invention can be applied to a device according to a general organic light emitting device manufacturing method.

The organic light emitting device according to an embodiment of the present invention may have a structure including a first electrode and a second electrode and an organic material layer disposed therebetween. Except for this, it may be manufactured using conventional device manufacturing methods and materials.

The organic material layer of the organic light emitting device according to the present invention may have a single-layer structure, but may have a multi-layer structure in which two or more organic material 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, an electron blocking layer, a hole blocking layer, a light efficiency improving layer (Cappinglayer), and the like. However, the present invention is not limited thereto and may include a smaller number or a larger number of organic material layers.

In addition, the organic electroluminescent device according to an embodiment of the present invention includes a substrate, a first electrode (anode), an organic material layer, a second electrode (cathode) and a light efficiency improving layer, wherein the light efficiency improving layer is a lower portion of the first electrode ( Bottom emission) or it may be formed on top of the second electrode (Top emission).

In the method formed on the second electrode top (Top emission), the light formed in the light emitting layer is emitted toward the cathode, and the light emitted toward the cathode passes through the light efficiency improvement layer (CPL) formed of the compound according to the present invention having a relatively high refractive index. The wavelength of the wavelength is amplified and thus the light efficiency is increased .

The organic material layer structure of the preferred organic light emitting device according to the present invention will be described in more detail in the following Examples.

In addition, the organic light emitting device according to the present invention uses a PVD (physical vapor deposition) method, such as sputtering or e-beam evaporation, to form a metal or a conductive metal oxide or an alloy thereof on a substrate. It can be prepared by depositing an anode, forming an organic material layer including a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer thereon, and then depositing a material that can be used as a cathode thereon.

In addition to this method, an organic light emitting diode may be manufactured by sequentially depositing a cathode material, an organic material layer, and an anode material on a substrate. The organic material layer may have a multilayer structure including a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer, but is not limited thereto and may have a single layer structure. In addition, the organic layer is formed using a variety of polymer materials by a solvent process rather than a deposition method, such as spin coating, dip coating, doctor blading, screen printing, inkjet printing, or a thermal transfer method. It can be made in layers.

As the anode material, a material having a large work function is generally preferred so that holes can be smoothly injected into the organic material layer. Specific examples of the anode material that can be used in the present invention include metals such as vanadium, chromium, copper, zinc, gold, or alloys thereof, zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), etc. Metal oxides, combinations of metals and oxides such as ZnO:Al or SnO ₂ :Sb, poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDT) , a conductive polymer such as polypyrrole and polyaniline, but is not limited thereto.

The cathode material is preferably a material having a small work function to facilitate electron injection into the organic material layer. Specific examples of the negative electrode material include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead or alloys thereof, and multilayers such as _{LiF/Al or LiO 2 /Al} Structural materials and the like, but are not limited thereto.

The hole injection material is a material capable of well injecting holes from the anode at a low voltage, and it is preferable that the highest occupied molecular orbital (HOMO) of the hole injection material is between the work function of the positive electrode material and the HOMO of the surrounding organic material layer. Specific examples of the hole injection material include metal porphyrine, oligothiophene, arylamine-based organic material, hexanitrile hexaazatriphenylene, quinacridone-based organic material, perylene-based organic material, anthraquinone, polyaniline, and polythiophene-based conductive polymers, but is not limited thereto.

As the hole transport material, a material capable of transporting holes from the anode or the hole injection layer to the light emitting layer is suitable, and a material having high hole mobility is suitable. Specific examples include an arylamine-based organic material, a conductive polymer, and a block copolymer having a conjugated portion and a non-conjugated portion together. can be further improved.

The light emitting material is a material capable of emitting light in the visible ray region by receiving and combining holes and electrons from the hole transport layer and the electron transport layer, respectively, and a material having good quantum efficiency for fluorescence or phosphorescence is preferable. Specific examples include 8-hydroxy-quinoline aluminum complex (Alq ₃ ), carbazole-based compounds, dimerized styryl compounds, BAlq, 10-hydroxybenzoquinoline-metal compounds, benzoxazole, benzthiazole and Benzimidazole-based compounds, poly(p-phenylenevinylene) (PPV)-based polymers, spiro compounds, polyfluorene, rubrene, and the like, but are not limited thereto.

As the electron transport material, a material capable of receiving electrons from the cathode and transferring them to the light emitting layer is suitable, and a material having high electron mobility is suitable. Specific examples include, but are not limited to, an Al complex of 8-hydroxyquinoline _{, a complex including Alq 3} , an organic radical compound, and a hydroxyflavone-metal complex.

The organic light emitting device according to the present invention may be a top emission type, a back emission type, or a double side emission type depending on the material used.

In addition, the organic light emitting compound according to the present invention can act on a principle similar to that applied to the organic light emitting device in an organic electronic device including an organic solar cell, an organic photoreceptor, an organic transistor, and the like.

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. However, these examples are for explaining the present invention in more detail, the scope of the present invention is not limited thereby, and it is common in the art that various changes and modifications are possible within the scope and spirit of the present invention. It will be self-evident to those with knowledge.

Synthesis example 1: Synthesis of compound 5

(One) manufacturing example 1: Synthesis of Intermediate 5-1

4,6-Dibromodibenzofuran (10 g, 0.031 mol, TCI), Phenylboronic acid (8.98 g, 0.074 mol, sigma aldrich), potassium carbonate (25.4 g, 0.184 mol, sigma aldrich), Pd(PPh ₃ ) ₄ (0.71 g) , 0.0006 mol, sigma aldrich), toluene 200 mL, ethanol 50 mL, H ₂ O 50 mL, and reacted by stirring under reflux at 100 °C for 6 hours. After completion of the reaction, extraction and column purification were performed to obtain 7.1 g (yield 72.2%) of <Intermediate 5-1>.

(2) manufacturing example 2: Synthesis of intermediate 5-2

Intermediate 5-1 (10 g, 0.031 mol) and N-Bromosuccinimide (13.3 g, 0.075 mol, sigma aldrich) were added to 200 mL of DMF and reacted by stirring at room temperature for 5 hours. After completion of the reaction, extraction was performed and column purification was performed to obtain 11.2 g (yield 75.0%) of <Intermediate 5-2>.

(3) manufacturing example 3: Synthesis of compound 5

Intermediate 5-2 (10 g, 0.021 mol), tert-butylboronic acid (5.12 g, 0.050 mol, mascot), tripotassium phosphate (22.2 g, 0.105 mol, sigma aldrich), Pd ₂ (dba) ₃ (0.96 g, 0.001) mol, sigma aldrich), and the ligand S-Phos (0.86 g, 0.002 mol, sigma aldrich) were added with 200 mL of toluene, and reacted by stirring under reflux at 90° C. for 16 hours. After completion of the reaction, extraction was performed and column purification was performed to obtain 8.1 g (yield 58.1%) of <Compound 5>.

H-NMR (200MHz, CDCl3): δ ppm, 2H (7.48/s, 7.44/s, 7.41/m) 4H (7.52/d, 7.51/d) 18H (1.35/s)

LC/MS: m/z=432 [(M+1) ⁺ ]

Synthesis example 2: Synthesis of compound 13

(One) manufacturing example 1: Synthesis of compound 13

2,4,6,8-tetrabromodibenzofuran (10 g, 0.017 mol, mascot), 3-Biphenylboronic acid (14.8 g, 0.083 mol, sigma aldrich), potassium carbonate (28.8 g, 0.208 mol, sigma aldrich), Pd(PPh) ₃ ) ₄ (0.8 g, 0.0007 mol, sigma aldrich), 200 mL of toluene, 50 mL of ethanol, and 50 mL of H ₂ O were added, and the reaction was stirred under reflux at 100 °C for 6 hours. After completion of the reaction, extraction and column purification were performed to obtain 9.1 g (yield 78.9%) of <Compound 13>.

H-NMR (200 MHz, CDCl3): δ ppm, 2H (7.67/s, 7.63/s) 4H (7.70/s, 7.57/m, 7.41/m) 8H (7.52/d, 7.51/m, 7.48/d)

LC/MS: m/z=776[(M+1) ⁺ ]

Synthesis example 3: Synthesis of compound 27

(One) manufacturing example 1: Synthesis of intermediate 27-1

4,6-Dibromodibenzofuran (10 g, 0.031 mol, TCI), 4-tert-Butylphenylboronic acid (13.1 g, 0.074 mol, sigma aldrich), potassium carbonate (25.4 g, 0.184 mol, sigma aldrich), Pd(PPh ₃ ) ₄ (0.71 g, 0.0006 mol, sigma aldrich), 200 mL of toluene, 50 mL of ethanol, and 50 mL of H ₂ O were added, and the reaction was stirred under reflux at 100 °C for 6 hours. After completion of the reaction, extraction and column purification were performed to obtain 9.2 g (yield 69.3%) of <Intermediate 27-1>.

(2) manufacturing example 2: Synthesis of intermediate 27-2

Intermediate 27-1 (10 g, 0.023 mol) and N-Bromosuccinimide (9.9 g, 0.056 mol, sigma aldrich) were added to 200 mL of DMF and reacted by stirring at room temperature for 5 hours. After completion of the reaction, extraction was performed and column purification was performed to obtain 8.9 g (yield 64.1%) of <Intermediate 27-2>.

(3) manufacturing example 3: Synthesis of compound 27

Intermediate 27-2 (10 g, 0.017 mol), 2-Biphenylboronic acid (8.05 g, 0.041 mol, sigma aldrich) potassium carbonate (14.1 g, 0.102 mol, sigma aldrich), Pd(PPh ₃ ) ₄ (0.39 g, 0.0003) mol, sigma aldrich), toluene 200 mL, ethanol 50 mL, H ₂ O 50 mL, and reacted by stirring under reflux at 100 °C for 6 hours. After completion of the reaction, extraction and column purification were performed to obtain 8.9 g (yield 71.3%) of <Compound 27>.

H-NMR (200MHz, CDCl3): δ ppm, 2H (7.67/s, 7.63/s, 7.41/m) 4H (7.85/d, 7.79/d, 7.51/m, 7.47/m, 7.38/d, 7.37/d ) 18H (1.35/s)

LC/MS: m/z=736[(M+1) ⁺ ]

Synthesis example 4: Synthesis of compound 62

(One) manufacturing example 1: Synthesis of Intermediate 62-1

4,6-Dibromodibenzofuran (10 g, 0.031 mol, TCI), (2-(tert-Butyl)phenyl)boronic acid (13.1 g, 0.074 mol, mascot), potassium carbonate (25.4 g, 0.184 mol, sigma aldrich), Pd(PPh ₃ ) ₄ (0.71 g, 0.0006 mol, sigma aldrich), 200 mL of toluene, 50 mL of ethanol, and 50 mL of H ₂ O were added, and the reaction was stirred under reflux at 100 °C for 6 hours. After completion of the reaction, extraction and column purification were performed to obtain 8.4 g (yield 63.3%) of <Intermediate 62-1>.

(2) manufacturing example 2: Synthesis of Intermediate 62-2

Intermediate 62-1 (10 g, 0.023 mol) and N-Bromosuccinimide (9.9 g, 0.056 mol, sigma aldrich) were added to 200 mL of DMF and reacted by stirring at room temperature for 5 hours. After completion of the reaction, extraction was performed and column purification was performed to obtain 10.2 g (yield 74.7%) of <Intermediate 62-2>.

(3) manufacturing example 3: Synthesis of compound 62

Intermediate 62-2 (10 g, 0.017 mol), 3,5-Di-tert-butylphenylboronic Acid (9.52 g, 0.041 mol, TCI) potassium carbonate (14.1 g, 0.102 mol, sigma aldrich), Pd(PPh ₃ ) ₄ (0.39 g, 0.0003 mol, sigma aldrich), 200 mL of toluene, 50 mL of ethanol, and 50 mL of H ₂ O were added, and the reaction was stirred under reflux at 100 °C for 6 hours. After completion of the reaction, extraction and column purification were performed to obtain 9.3 g of <Compound 62> (yield 67.9%).

H-NMR (200 MHz, CDCl3): δ ppm, 2H (7.71/d, 7.67/s, 7.63/s, 7.52/d, 7.41/s, 7.33/m, 7.31/m) 4H (7.82/s) 54H (1.35) /s)

LC/MS: m/z=808[(M+1) ⁺ ]

Synthesis example 5: Synthesis of compound 99

(One) manufacturing example 1: Synthesis of intermediate 99-1

4,6-Dibromodibenzothiophene (10 g, 0.029 mol, TCI), Naphthalene-1-boronic acid (12.1 g, 0.070 mol, sigma aldrich), potassium carbonate (24.2 g, 0.175 mol, sigma aldrich), Pd(PPh ₃ ) ₄ (0.68 g, 0.0006 mol, sigma aldrich), toluene 200 mL, ethanol 50 mL, and H ₂ O 50 mL were added, and the reaction was stirred under reflux at 100 °C for 6 hours. After completion of the reaction, extraction and column purification were performed to obtain 9.5 g (yield 74.4%) of <Intermediate 99-1>.

(2) manufacturing example 2: Synthesis of intermediate 99-2

Intermediate 99-1 (10 g, 0.023 mol) and N-Bromosuccinimide (9.8 g, 0.055 mol, sigma aldrich) were added to 200 mL of DMF and reacted by stirring at room temperature for 5 hours. After completion of the reaction, extraction was performed and column purification was performed to obtain 9.5 g (yield 69.8%) of <Intermediate 99-2>.

(3) manufacturing example 3: Synthesis of compound 99

Intermediate 99-2 (10 g, 0.017 mol), 4-Fluoro-1-naphthaleneboronic Acid (7.67 g, 0.040 mol, sigma aldrich), potassium carbonate (13.9 g, 0.101 mol, sigma aldrich), Pd(PPh ₃ ) ₄ (0.39 g, 0.0003 mol, sigma aldrich), 200 mL of toluene, 50 mL of ethanol, and 50 mL of H ₂ O were added, and the reaction was stirred under reflux at 100 °C for 6 hours. After completion of the reaction, extraction and column purification were performed to obtain 7.5 g of <Compound 99> (yield 61.5%).

H-NMR (200 MHz, CDCl3): δ ppm, 2H (8.42/d, 8.04/d, 7.96/s, 7.93/d, 7.75/s, 7.61/m, 7.09/d) 4H (8.55/d, 8.08/d) ) 8H (7.55/m)

LC/MS: m/z=724 [(M+1) ⁺ ]

Synthesis example 6: Synthesis of compound 131

(One) manufacturing example 1: Synthesis of intermediate 131-1

4,6-Dibromodibenzothiophene (10 g, 0.029 mol, TCI), 3,5-Di-tert-butylphenylboronic Acid (16.4 g, 0.070 mol, TCI) potassium carbonate (24.2 g, 0.175 mol, sigma aldrich), Pd(PPh) ₃ ) ₄ (0.68 g, 0.0006 mol, sigma aldrich), 200 mL of toluene, 50 mL of ethanol, and 50 mL of H ₂ O were added, and the reaction was stirred under reflux at 100 °C for 6 hours. After completion of the reaction, extraction and column purification were performed to obtain 10.7 g (yield 67.2%) of <Intermediate 131-1>.

(2) manufacturing example 2: Synthesis of intermediate 131-2

Intermediate 131-1 (10 g, 0.018 mol) and N-Bromosuccinimide (7.8 g, 0.044 mol, sigma aldrich) were added to 200 mL of DMF and reacted by stirring at room temperature for 5 hours. After completion of the reaction, extraction was performed and column purification was performed to obtain 8.2 g (yield 63.6%) of <Intermediate 131-2>.

(3) manufacturing example 3: Synthesis of compound 131

Intermediate 131-2 (10 g, 0.014 mol), (2-(tert-Butyl)phenyl)boronic acid (6.08 g, 0.034 mol, mascot), potassium carbonate (11.8 g, 0.085 mol, sigma aldrich), Pd(PPh) ₃ ) ₄ (0.33 g, 0.0003 mol, sigma aldrich), 200 mL of toluene, 50 mL of ethanol, and 50 mL of H ₂ O were added, and the reaction was stirred under reflux at 100 °C for 6 hours. After completion of the reaction, extraction and column purification were performed to obtain 7.2 g (yield 61.3%) of <Compound 131>.

H-NMR (200 MHz, CDCl3): δ ppm, 2H (7.96/s, 7.75/s, 7.71/d, 7.52/d, 7.41/s, 7.33/m, 7.31/m) 4H (7.82/s) 54H (1.35) /s)

LC/MS: m/z=824 [(M+1) ⁺ ]

Device embodiment (capping layer)

In the embodiment according to the present invention, the ITO transparent electrode was cleaned using an ITO glass substrate containing 25 mm × 25 mm × 0.7 mm Ag, after patterning so that the emission area was 2 mm × 2 mm in size. After the substrate was mounted in a vacuum chamber, the base pressure was 1 × 10 ^-6 torr or more, and an organic material and a metal were deposited on the Ag-containing ITO glass substrate in the following structure.

Device Examples 1 to 10

By employing the compound implemented according to the present invention in the light efficiency improving layer, a blue organic light emitting device having the following device structure was manufactured, and light emission characteristics including light emission efficiency were measured.

Ag/ITO / hole injection layer (HAT-CN, 5 nm) / hole transport layer (α-NPB, 100 nm) / electron blocking layer (TCTA, 10 nm) / light emitting layer (20 nm) / electron transport layer (201: Liq, 30 nm) / LiF (1 nm) / Mg:Ag (15 nm) / Light efficiency improvement layer (70 nm)

HAT-CN was formed to a thickness of 5 nm to form a hole injection layer on an ITO transparent electrode containing Ag on a glass substrate, and then α-NPB was formed as a film of 100 nm for the hole transport layer. The electron blocking layer was formed of TCTA with a thickness of 10 nm. In addition, the light emitting layer was co-deposited at 20 nm using BH1 as a host compound and BD1 as a dopant compound. Further, an electron transport layer (50% doped with [201] compound Liq below) was formed to a thickness of 30 nm and LiF 1 nm. Then, a film of 15 nm was formed of Mg:Ag in a ratio of 1:9. And as a light efficiency improving layer (capping layer) compound, compounds 5, 13, 27, 31, 62, 99, 120, 123, 129, 131 implemented in the present invention were formed into a film to a thickness of 70 nm to prepare an organic light emitting diode. .

Device Comparative Example 1

The organic light emitting device for Device Comparative Example 1 was manufactured in the same manner except that the light efficiency improving layer was not used in the device structures of Examples 1 to 10.

Device Comparative Example 2

The organic light emitting device for Device Comparative Example 2 was manufactured in the same manner except that _{Alq 3} was used instead of the compound of the present invention as the light efficiency improving layer compound in the device structures of Examples 1 to 10.

Experimental Example 1: Light emitting properties of Device Examples 1 to 10

The organic light emitting device manufactured according to the above example was measured using a source meter (Model 237, Keithley) and a luminance meter (PR-650, Photo Research) to measure driving voltage, current efficiency, and color coordinates, and the result value based on 1,000 nits is shown in [Table 1] below.

Example Light efficiency improvement layer V cd/A CIEx CIEy One Formula 5 3.7 8.6 0.140 0.042 2 Formula 13 3.6 8.8 0.141 0.042 3 Formula 27 3.8 8.6 0.142 0.041 4 Formula 31 3.7 8.7 0.142 0.040 5 Formula 62 3.6 8.9 0.140 0.040 6 Formula 99 3.9 8.3 0.142 0.041 7 Formula 120 3.7 8.7 0.141 0.040 8 Formula 123 3.8 8.5 0.142 0.041 9 Formula 129 3.9 8.4 0.141 0.041 10 Formula 131 3.7 8.6 0.140 0.040 Comparative Example 1 not used 4.5 7.0 0.151 0.140 Comparative Example 2 Alq ₃ 4.3 7.8 0.149 0.057

Looking at the results shown in [Table 1], when the compound according to the present invention is applied to the device as a light efficiency improving layer, compared to the conventional device (Comparative Examples 1 and 2), it can be confirmed that the driving voltage is reduced and the current efficiency is improved. have.

[HAT-CN] [α-NPB] [BH1] [BD1] [201]

[TCTA]

Claims (6)

An organic light emitting compound represented by the following [Formula I] and employed in the light efficiency improvement layer (Capping layer) of the organic light emitting device:
[Formula Ⅰ]

In the [Formula I],
X is O or S;
Ar _{1 To} Ar ₂ are the same as or different from each other, and each independently represents a substituted or unsubstituted phenyl group, or a substituted or unsubstituted naphthyl group,
Ar ₃ to Ar ₄ are the same as or different from each other, and each independently a substituted or unsubstituted C 1 to C 20 alkyl group, a substituted or unsubstituted C 3 to C 20 cycloalkyl group, a substituted or unsubstituted phenyl group, or substituted or an unsubstituted naphthyl group,
However, when Ar ₃ to Ar ₄ are each independently selected from a substituted or unsubstituted C 1 to C 20 alkyl group and a substituted or unsubstituted C 3 to C 20 cycloalkyl group, Ar ₁ to Ar ₂ are each independently unsubstituted any one selected from a phenyl group, an unsubstituted biphenyl group, and an unsubstituted terphenyl group,
In the _{definition of Ar 1} to Ar ₄ , 'substituted or unsubstituted' means deuterium, a halogen group, a cyano group, a nitro group, a hydroxyl group, a silyl group, an alkyl group, a cycloalkyl group, an alkoxy group, a phenyl group, a biphenyl group, and a naphthyl group. It means that it is substituted with one or two or more substituents selected from the group consisting of, or is substituted with a substituent to which two or more of the substituents are connected, or does not have any substituents,
However, the _{case in which all Ar 1} to Ar ₄ is a phenyl group substituted with a halogen group is excluded. According to claim 1,
The [Formula I] is an organic light emitting compound, characterized in that selected from the following [Compound 1] to [Compound 132]:

An organic light emitting device comprising a first electrode, a second electrode, and at least one organic material layer disposed between the first electrode and the second electrode,
Further comprising a light efficiency improvement layer (Capping layer) formed on at least one side opposite to the organic material layer among the upper or lower portions of the first electrode and the second electrode,
The light efficiency improving layer is an organic light emitting device comprising the organic light emitting compound according to claim 1 . delete delete 4. The method of claim 3,
The light efficiency improving layer is an organic light emitting device, characterized in that formed on at least one of a lower portion of the first electrode or an upper portion of the second electrode.

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