KR20200141748A - An electroluminescent compound and an electroluminescent device comprising the same - Google Patents

Abstract

The present invention relates to an organic light-emitting compound represented by chemical formula I and employed as a hole transport material in an organic light-emitting device, and to an organic light-emitting device capable of driving low voltage using the same and having improved light-emitting efficiency.

Description

An organic light emitting compound and an organic light emitting device comprising the same {An electroluminescent compound and an electroluminescent device comprising the same}

The present invention relates to an organic light-emitting compound, and more particularly, to an organic light-emitting compound employed as a hole transport material for an organic light-emitting device, and an organic light-emitting device capable of low voltage driving by employing the same and improved luminous efficiency.

Recently, organic light-emitting devices capable of low voltage driving by self-luminous type have superior viewing angles and contrast ratios compared to liquid crystal displays, which are the mainstream of flat panel display devices, do not require a backlight, are lightweight and thin, are advantageous in terms of power consumption, and color reproduction range Is attracting attention as a next-generation display device.

An organic light-emitting device is a device that emits light as electrons and holes form a pair and then disappear when electric charges are injected into the organic light-emitting layer formed between the electron injection electrode (cathode) and the hole injection electrode (anode). In addition to being able to form a device on a substrate, it is possible to drive at a lower voltage of 10 V or less compared to a plasma display panel or an inorganic light emitting display, consumes relatively little power, and has an excellent color. In addition, the organic light emitting device is capable of displaying three colors of green, blue, and red, and thus is a subject of much interest as a next-generation rich color display device.

In the organic light emitting device, the processes for emitting light, that is, charge injection, charge transport, photoexcitation formation, and light generation, are divided into roles using different organic layers. Accordingly, an organic light-emitting device having a structure subdivided into layers including a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, etc. between the anode and the cathode is used, and the organic light-emitting device has the above-described characteristics. In order to demonstrate this, it must first be supported by a stable and efficient material such as a hole injection material, a hole transport material, a light emitting material, an electron transport material, an electron injection material, an electron blocking material, etc., which constitute the organic layer in the device. The development of an efficient and efficient organic material layer material for an organic light-emitting device has not been made sufficiently.

Therefore, in order to realize a more stable organic light emitting device, and to achieve high efficiency, long life, and large size of the device, additional improvement is required in terms of efficiency and lifespan characteristics. In this regard, recently, a hole transport layer among the structures of the organic light emitting device For materials, research has been conducted to further provide a layer containing a p-type material between the electrode and the hole transport layer by doping or subdividing the layer with a p-type material to improve the mobility of the existing organic material. Is losing.

In particular, when doping with organic materials, negative conductivity is formed, so that even a thick transport layer can lower the voltage drop in the transport layer, and a thin space charge layer formed by increasing the doping level enables charge injection by tunneling effectively. By doping the hole transport layer, it is possible to control the high conductivity of the hole transport layer and the charge density of the charge carrier, and as a result, the conductivity of the organic material layer is improved to improve the characteristics of the device, thereby realizing a device with low driving voltage and high efficiency.

However, there are still problems such as poor process efficiency due to the application of additional organic materials and organic layers, and it is difficult to implement low voltage driving due to the thickness of the organic layer.

Accordingly, the present invention is to solve the above problems, as a p-type doping material (p-dopant) for the hole transport material, or a material of a layer including a p-type doping material adjacent to the hole transport layer, furthermore Provides a compound of a fused material structure that can be collected together with p-doping and hole transport without separate p-doping, and introduced them to stably realize characteristics such as improved luminous efficiency and long life, It is intended to provide an organic light-emitting device capable of implementing low voltage driving at the same level or higher.

In order to solve the above problems, the present invention provides a p-type doping material (p-dopant) represented by the following [Chemical Formula I], and each moiety having a p-doping function and hole transport property. It provides an organic light-emitting device comprising an organic light-emitting compound introduced into the structure of and at least one light-emitting compound represented by [Chemical Formula I] in an organic layer.

[Chemical Formula Ⅰ]

The structure and substituent of [Chemical Formula I] will be described later.

The organic light-emitting compound according to the present invention is a p-doping material for the hole transport material, through which it is possible to control the high conductivity of the hole transport layer and the charge density of the charge carrier, and eventually the conductivity of the organic material layer is improved. As the characteristics are improved, it is possible to implement a device with low driving voltage and high efficiency.

In addition, it is characterized by fusion of a p-doping function and a hole transport property, and the device incorporating it improves the hole transport rate without additional p-doping compared to the conventional device, thereby improving luminous efficiency and It is possible to implement low voltage driving at an equivalent level or higher than that of conventional devices, so it can be usefully used for various display devices. Can be improved.

1 is a representative diagram 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 introduces a p-doping material for the hole transport material, and furthermore, each moiety having a p-doping function and hole transport property into one structure to provide a separate p-doping. The present invention relates to an organic light-emitting compound represented by the following [Chemical Formula I], which can realize a low-voltage driving characteristic of a device without having to do so, and to achieve improved luminous efficiency of the device by excellent hole transport.

[Chemical Formula Ⅰ]

In the above [Formula I],

X ₁ and X ₂ are the same as or different from each other, and may each independently be O, S or NR.

In addition, R is hydrogen, deuterium, a halogen group, a cyano group, a substituted or unsubstituted alkyl group having 1 to 24 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 24 carbon atoms, a substituted or unsubstituted C 1 to 24 It is selected from a halogenated alkyl group, a substituted or unsubstituted halogenated alkoxy group having 1 to 24 carbon atoms, a substituted or unsubstituted aryl group having 6 to 24 carbon atoms, and a substituted or unsubstituted heteroaryl group having 3 to 24 carbon atoms.

Z ₁ to Z ₆ may be the same as or different from each other, and each independently N, or may be CR ₁ to CR ₆ .

In addition, the R ₁ to R ₆ and R ₇ to R ₁₂ are each independently hydrogen, deuterium, a halogen group, a cyano group, a substituted or unsubstituted C1-C24 alkyl group, a substituted or unsubstituted C2-C24 Alkenyl group, substituted or unsubstituted alkoxy group having 1 to 24 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 24 carbon atoms, substituted or unsubstituted halogenated alkoxy group having 1 to 24 carbon atoms, substituted or unsubstituted It is selected from an aryl group having 6 to 24 carbon atoms or a substituted or unsubstituted heteroaryl group having 3 to 24 carbon atoms.

In addition, the R ₁ to R ₁₂ may be bonded to each other or connected with an adjacent substituent to form an alicyclic, aromatic monocyclic or polycyclic ring, and the formed alicyclic, aromatic monocyclic or polycyclic carbon atoms are It may be substituted with any one or more heteroatoms selected from N, S and O.

Meanwhile, in [Chemical Formula I], the term'substituted or unsubstituted' means that each of R and R ₁ to R ₁₂ may be further substituted with one or more substituents, and the one or more substituents Deuterium, cyano group, halogen group, amino group, thiol group, hydroxy group, nitro group, alkyl group having 1 to 24 carbon atoms, halogenated alkyl group having 1 to 24 carbon atoms, alkenyl group having 2 to 24 carbon atoms, aryl group having 6 to 24 carbon atoms , C2-C24 heteroaryl group, C1-C24 alkoxy group, C1-C24 C1-C24 alkylsilyl group, and C1-C24 arylsilyl group are selected from the group consisting of.

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

In the present invention, the alkyl group may be a straight chain or branched chain, and specific examples are 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, and the like, but are not limited thereto. In addition, the halogenated alkyl group is a group formed by substitution of an alkyl group by a halogen atom.

In the present invention, the aryl group may be monocyclic or polycyclic, examples of the monocyclic aryl group include a phenyl group, a biphenyl group, a terphenyl group, a stilbene group, and examples of the polycyclic aryl group include a naphthyl group, an anthracenyl group. , Phenanthrenyl group, pyrenyl group, perylenyl group, tetrasenyl group, chrysenyl group, fluorenyl group, acenaphthacenyl group, triphenylene group, fluoranthrene group, etc., but the scope of the present invention It is not limited to these examples.

In the present invention, the heteroaryl group is a heterocyclic group containing O, N or S as a heteroatom, and examples of the heterocyclic group include thiophene group, furan group, pyrrole group, imidazole group, thiazole group, oxazole group, oxa Diazole group, triazole group, pyridyl group, bipyridyl group, pyrimidyl group, triazine group, triazole group, acridyl group, pyridazine group, pyrazinyl group, quinolinyl group, quinazoline group, quinoxalinyl group, phthalazinyl Group, pyrido pyrimidinyl group, pyrido pyrazinyl group, pyrazino pyrazinyl group, isoquinoline group, indole group, carbazole group, benzoxazole group, benzoimidazole group, benzothiazole group, benzocarbazole group, benzothiophene Group, dibenzothiophene group, benzofuranyl group, dibenzofuranyl group, phenanthroline group, thiazolyl group, isoxazolyl group, oxadiazolyl group, thiadiazolyl group, benzothiazolyl group, phenothiazinyl group, etc. However, it is not limited to these.

In the present invention, examples of the halogen group include fluorine, chlorine, bromine or iodine.

In the present invention, the aryl group in the arylsilyl group is the same as the example of the aryl group described above, and the silyl group is specifically trimethylsilyl group, triethylsilyl group, t-butyldimethylsilyl group, vinyldimethylsilyl group, propyldimethylsilyl group , Triphenylsilyl group, diphenylsilyl group, phenylsilyl group, and the like, but are not limited thereto.

Specific examples of the alkoxy group as a substituent used in the present invention include methoxy, ethoxy, propoxy, isobutyloxy, sec-butyloxy, pentyloxy, iso-amyloxy, hexyloxy, and the like, and the alkoxy group At least one of the hydrogen atoms may be substituted with the same substituent as in the case of the aryl group, and the halogenated alkoxy group is a group formed by substituting an alkoxy group with a halogen atom.

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

Specific examples of the alkenyl group used in the present invention represent a linear or branched alkenyl group, 3-pentenyl group, 4-hexenyl group, 5-heptenyl group, 4-methyl-3-pentenyl group, 2,4 -Dimethyl-pentenyl group, 6-methyl-5-heptenyl group, 2,6-dimethyl-5-heptenyl group, etc. are mentioned.

The organic light-emitting compound according to the present invention represented by [Chemical Formula I] may be used as an organic material layer of an organic light-emitting device due to its structural specificity, and more specifically, as a hole transport material in the organic material layer.

In particular, it can be used as a p-type dopant to control the high conductivity of the hole transport layer formed on the ITO substrate and the charge density of the charge carrier, or can be used for a layer made of p-type dopant formed adjacent to the hole transport layer. Further, a single hole transport layer made of a compound represented by [Chemical Formula I] or [Chemical Formula II] may be applied without a separate p-type dopant process or insertion.

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

As described above, the organic light-emitting compound according to the present invention has a p-doping function, and furthermore, each moiety having p-doping and hole transport characteristics is introduced into one structure, and each of the introduced substituents An organic light-emitting compound having intrinsic characteristics can be synthesized, and as a result, when the organic light-emitting compound according to the present invention is applied as a material for a hole transport layer, the low-voltage driving characteristics, luminous efficiency, and lifetime characteristics of the device can be further improved.

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, a second electrode, and an organic material layer disposed therebetween, and that the organic light emitting compound according to the present invention is used for the organic material layer of the device. Except, it can 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 multilayer 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, and the like, and may further include a p-dopant layer adjacent to the hole transport layer, and is not limited thereto. It may include a number or a greater number of organic material layers.

Therefore, in the organic light emitting device according to the present invention, the organic material layer may include a hole transport layer, a layer that simultaneously injects and transports holes, or one or more of a p-dopant layer formed adjacent thereto, and the layers One or more of the layers may include the compound represented by [Chemical Formula I].

The organic material layer structure of the 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, and uses a metal or conductive metal oxide or alloy thereof on a substrate. It can be prepared by depositing an anode to form 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 device 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, an emission layer, an electron transport layer, and the like, but is not limited thereto and may have a single layer structure. In addition, the organic material layer is made of a variety of polymer materials, and is used in a smaller number of solvent processes, such as spin coating, dip coating, doctor blading, screen printing, inkjet printing, or thermal transfer. It can be made in layers.

As the anode material, a material having a large work function is preferable so that hole injection into the organic material layer can be smoothly performed. 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), and indium zinc oxide (IZO). 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) , Polypyrrole and conductive polymers such as polyaniline, but are not limited thereto.

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

As the hole transport material, a material capable of transporting holes from the anode or the hole injection layer and transferring them to the emission layer, and a material having high mobility for holes 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, but the low-voltage driving characteristics, luminous efficiency, and lifetime characteristics of the device using the organic light-emitting compound according to the present invention. Can be further improved.

As a light emitting material, a material capable of emitting light in a visible light region by transporting 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 There are 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, and a material having high mobility for electrons 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 of a top emission type, a bottom emission type, or a double-sided 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 an organic light-emitting device in organic electronic devices including organic solar cells, organic photoreceptors, and organic transistors.

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

Synthesis Example 1: Synthesis of Compound 1

(1) Preparation Example 1: Synthesis of Intermediate 1-1

1,2-Phenylenediamine (10 g, 0.092 mol), 1,1'-carbonyldiimidazole (18 g, 0.111 mol), and 300 mL of DMF were added and stirred at room temperature for 24 hours to react. After completion of the reaction, extraction was performed and recrystallized to give 9.2 g (yield 74.2%) of <Intermediate 1-1>.

(2) Preparation Example 2: Synthesis of Intermediate 1-2

Intermediate 1-1 (10 g, 0.075 mol), potassium hydroxide (20.9 g, 0.373 mol) H ₂ O 30 mL, 1,4-dioxane 400 mL added K ₃ Fe(CN) ₆ (73.6 g, 0.224 mol) After adding a solution (420 mL of H ₂ O) dropwise, the mixture was stirred at 100° C. for 12 hours to react. After completion of the reaction, extraction was performed and column purification was performed to obtain 3.5 g (35.5% yield) of <Intermediate 1-2>.

(3) Preparation Example 3: Synthesis of Intermediate 4-3

Diethyl malonate (25.5 g, 0.159 mol) and THF 400 mL were added, cooled to 0 ℃, stirred, and sodium hydride (2.54 g, 0.106 mol) was slowly added dropwise and stirred for 1 hour. Intermediate 1-2 (10 g, 0.076 mol) dissolved in THF 60 mL was added and stirred at room temperature for 12 hours to react. After completion of the reaction, extraction was performed and 15.7 g (75.6% yield) of <Intermediate 1-3> was obtained through column purification.

(4) Preparation Example 4: Synthesis of Intermediate 4-4

Intermediate 1-3 (10 g, 0.037 mol) and 2-Aminophenol (16.3 g, 0.150 mol) were added and stirred at 200° C. for 12 hours to react. After completion of the reaction, extraction was performed and recrystallized to obtain 9.5 g (71.5% yield) of compound 1.

H-NMR (200MHz, CDCl3): δppm, 2H (7.99/s, 7.86/m) 4H (7.74/m, 7.39/d)

LC/MS: m/z=364[(M+1) ⁺ ]

Synthesis Example 2: Synthesis of Compound 38

(1) Preparation Example 1: Synthesis of Intermediate 38-1

Quinoxaline-2,3-diamine (10 g, 0.062 mol), 1,1'-carbonyldiimidazole (12.1 g, 0.075 mol), and 200 mL of DMF were added and stirred at room temperature for 24 hours to react. After completion of the reaction, extraction was performed and recrystallized to obtain 8.6 g (73.9% yield) of <Intermediate 38-1>.

(2) Preparation Example 2: Synthesis of Intermediate 38-2

Intermediate 38-1 (10 g, 0.054 mol), potassium hydroxide (15.1 g, 0.269 mol) H ₂ O 20 mL, 1,4-dioxane 400 mL added K ₃ Fe(CN) ₆ (53 g, 0.161 mol) After adding a solution (420 mL of H ₂ O) dropwise, the mixture was stirred at 100° C. for 12 hours to react. After completion of the reaction, extraction was performed and column purification was performed to give 3.5 g (35.4% yield) of <Intermediate 38-2>.

(3) Preparation Example 3: Synthesis of Intermediate 38-3

Diethyl malonate (18.3 g, 0.114 mol), THF 400 mL, cooled to 0 °C, stirred, and sodium hydride (1.82 g, 0.076 mol) was slowly added dropwise and stirred for 1 hour. Intermediate 38-2 (10 g, 0.054 mol) dissolved in THF 60 mL was added and stirred at room temperature for 12 hours to react. After completion of the reaction, extraction was performed and 13.3 g (75% yield) of <Intermediate 38-3> was obtained through column purification.

(4) Preparation Example 4: Synthesis of Intermediate 38-4

Intermediate 38-3 (10g, 0.031mol) and 3-aminoquinoxalin-2-ol (10.4 g, 0.064 mol) were added and stirred at 200° C. for 12 hours to react. After completion of the reaction, extraction was performed and recrystallized to give 8.9 g (68% yield) of <Intermediate 38-4>.

(5) Preparation Example 5: Synthesis of Compound 38

Intermediate 38-4 (10 g, 0.024 mol) and 2-Amino-4,5-difluorophenol (7.2 g, 0.050 mol) were added and stirred at 200° C. for 12 hours to react. After completion of the reaction, the mixture was extracted and recrystallized to give 8.5 g (71% yield) of compound 38.

H-NMR (200MHz, CDCl3): δppm, 2H (7.99/d, 7.86/m, 7.80/d, 7.67/m, 6.95/s)

LC/MS: m/z=504[(M+1) ⁺ ]

Synthesis Example 3: Synthesis of Compound 40

(1) Preparation Example 1: Synthesis of Intermediate 40-1

5,6-difluoropyrazine-2,3-diamine (10 g, 0.068 mol), 1,1'-carbonyldiimidazole (13.3 g, 0.082 mol), and 200 mL of DMF were added and stirred at room temperature for 24 hours to react. After completion of the reaction, extraction was performed and recrystallized to give 8.9 g (yield 75.6%) of <Intermediate 40-1>.

(2) Preparation Example 2: Synthesis of Intermediate 40-2

Intermediate 40-1 (10 g, 0.058 mol), potassium hydroxide (16.3 g, 0.291 mol) H ₂ O 20 mL, 1,4-dioxane 400 mL were added and K ₃ Fe(CN) ₆ (57.4 g, 0.174 mol) After adding a solution (420 mL of H ₂ O) dropwise, the mixture was stirred at 100° C. for 12 hours to react. After completion of the reaction, extraction was performed and column purification was performed to obtain 3.5 g (yield 35%) of <Intermediate 40-2>.

(3) Preparation Example 3: Synthesis of Intermediate 40-3

Diethyl malonate (19.8 g, 0.123 mol) and THF 400 mL were added, cooled to 0 ℃, stirred, sodium hydride (1.97 g, 0.082 mol) was slowly added dropwise and stirred for 1 hour. Intermediate 40-2 (10 g, 0.059 mol) dissolved in 60 mL of THF was added and stirred at room temperature for 12 hours to react. After completion of the reaction, extraction was performed and 13.2 g (72% yield) of <Intermediate 40-3> was obtained through column purification.

(4) Preparation Example 4: Synthesis of Compound 40

Intermediate 40-3 (10 g, 0.032 mol) and 3-aminodibenzo[b,d]furan-2-ol (26.2 g, 0.131 mol) were added and stirred at 200° C. for 12 hours to react. After completion of the reaction, extraction was performed and recrystallized to give 13.2 g (71% yield) of compound 40.

H-NMR (200MHz, CDCl3): δppm, 2H (7.89/d, 7.66/d, 7.49/s, 7.42/s, 7.38/m, 7.32/m)

LC/MS: m/z=582[(M+1) ⁺ ]

Synthesis Example 4: Synthesis of Compound 64

(1) Preparation Example 1: Synthesis of Intermediate 64-1

4,5-Difluoro-1,2-phenylenediamine (10 g, 0.069 mol), 1,1'-carbonyldiimidazole (13.5 g, 0.083 mol), and 200 mL of DMF were added and stirred at room temperature for 24 hours to react. After completion of the reaction, extraction was performed and recrystallized to obtain 8.4 g (71% yield) of <Intermediate 64-1>.

(2) Preparation Example 2: Synthesis of Intermediate 64-2

Intermediate 64-1 (10 g, 0.059 mol), potassium hydroxide (16.5 g, 0.294 mol) H ₂ O 20 mL, 1,4-dioxane 400 mL was added to K ₃ Fe(CN) ₆ (58.1 g, 0.177 mol) After adding a solution (420 mL of H ₂ O) dropwise, the mixture was stirred at 100° C. for 12 hours to react. After completion of the reaction, extraction was performed and column purification was performed to give 3.2 g (32% yield) of <Intermediate 64-2>.

(3) Preparation Example 3: Synthesis of Intermediate 64-3

Diethyl malonate (20 g, 0.125 mol), 400 mL of THF was added, cooled to 0 ℃, stirred, and sodium hydride (2 g, 0.083 mol) was slowly added dropwise and stirred for 1 hour. Intermediate 64-2 (10 g, 0.060 mol) dissolved in THF 60 mL was added and stirred at room temperature for 12 hours to react. After completion of the reaction, extraction was performed and 13.5 g (73.2% yield) of <Intermediate 64-3> was obtained through column purification.

(4) Preparation Example 4: Synthesis of Compound 64

Intermediate 64-3 (10 g, 0.032 mol) and 2-amino-4,5-difluorobenzenethiol (21.3 g, 0.132 mol) were added and stirred at 200° C. for 12 hours to react. After completion of the reaction, extraction was performed and recrystallized to give 11.1 g (68% yield) of compound 64.

H-NMR (200MHz, CDCl3): δppm, 2H (4.8/s, 8.01/s, 7.92/s)

LC/MS: m/z=503[(M+1) ⁺ ]

Synthesis Example 5: Synthesis of Compound 74

(1) Preparation Example 1: Synthesis of Intermediate 74-1

5,6-Diamino-2,3-dicyanopyrazine (10 g, 0.062 mol), 1,1'-carbonyldiimidazole (12.2 g, 0.075 mol), and 200 mL of DMF were added and stirred at room temperature for 24 hours to react. After completion of the reaction, the mixture was extracted and recrystallized to obtain 8.4 g (yield 72.3%) of <Intermediate 74-1>.

(2) Preparation Example 2: Synthesis of Intermediate 74-2

Intermediate 74-1 (10 g, 0.054 mol), potassium hydroxide (15.1 g, 0.269 mol) H ₂ O 20 mL, 1,4-dioxane 400 mL were added and K ₃ Fe(CN) ₆ (53.1 g, 0.161 mol) After adding a solution (420 mL of H ₂ O) dropwise, the mixture was stirred at 100° C. for 12 hours to react. After completion of the reaction, extraction was performed and column purification was performed to obtain 3.1 g (31.3% yield) of <Intermediate 74-2>.

(3) Preparation Example 3: Synthesis of Intermediate 74-3

Diethyl malonate (18.3 g, 0.114 mol), THF 400 mL, cooled to 0 °C, stirred, and sodium hydride (1.82 g, 0.076 mol) was slowly added dropwise and stirred for 1 hour. Intermediate 74-2 (10 g, 0.054 mol) dissolved in 60 mL of THF was added and stirred at room temperature for 12 hours to react. After completion of the reaction, extraction was performed and 13.3 g (75% yield) of <Intermediate 74-3> was obtained through column purification.

(4) Preparation Example 4: Synthesis of Compound 74

Intermediate 74-3 (10 g, 0.031 mol) and 2-amino-3,4,5,6-tetrafluorobenzenethiol (24.8 g, 0.126 mol) were added and stirred at 200° C. for 12 hours to react. After completion of the reaction, extraction was performed and recrystallized to give 12.9 g (71% yield) of compound 74.

Synthesis Example 6: Synthesis of Compound 83

(1) Preparation Example 1: Synthesis of Intermediate 83-1

Intermediate 1-3 (10 g, 0.021 mol) and 1,2-Phenylenediamine (16.2 g, 0.150 mol) were added and stirred at 200° C. for 12 hours to react. After completion of the reaction, extraction was performed and recrystallized to obtain 9.8 g (74% yield) of <Intermediate 83-1>.

(2) Preparation Example 2: Synthesis of Compound 83

A solution of intermediate 83-1 (10 g, 0.028 mol) in 20 mL of DMF was added to potassium hydroxide (0.8 g, 0.014 mol) and stirred at 20° C. for 15 minutes. Then, Iodomethane (0.9 g, 0.006 mol) was stirred dropwise for 3 hours to react. When the reaction was completed, the mixture was extracted and recrystallized to give 8.2 g (yield 76.1%) of compound 83.

H-NMR (200MHz, CDCl3): δppm, 2H (7.99/d, 7.86/m) 4H (7.59/d, 7.22/m) 6H (3.88/s)

LC/MS: m/z=390[(M+1) ⁺ ]

Synthesis Example 7: Synthesis of Compound 112

(1) Preparation Example 1: Synthesis of Intermediate 112-1

5,6-diaminopyrazine-2-carbonitrile (10 g, 0.074 mol), 1,1'-carbonyldiimidazole (14.4 g, 0.089 mol), and 200 mL of DMF were added and stirred at room temperature for 24 hours to react. After completion of the reaction, the mixture was extracted and recrystallized to obtain 8.4 g (70.5% yield) of <Intermediate 112-1>.

(2) Preparation Example 2: Synthesis of Intermediate 112-2

Intermediate 112-1 (10 g, 0.062 mol), potassium hydroxide (17.4 g, 0.310 mol) H ₂ O 20 mL, 1,4-dioxane 400 mL added K ₃ Fe(CN) ₆ (61.3 g, 0.186 mol) After adding a solution (420 mL of H ₂ O) dropwise, the mixture was stirred at 100° C. for 12 hours to react. After completion of the reaction, extraction was performed and column purification was performed to obtain 3.2 g (32.4% yield) of <Intermediate 112-2>.

(3) Preparation Example 3: Synthesis of Intermediate 112-3

Diethyl malonate (21.1 g, 0.132 mol) and THF 400 mL were added, cooled to 0 ℃, stirred, and sodium hydride (2.1 g, 0.088 mol) was slowly added dropwise and stirred for 1 hour. Intermediate 112-2 (10 g, 0.063 mol) dissolved in THF 60 mL was added and stirred at room temperature for 12 hours to react. After completion of the reaction, extraction was performed and 14.2 g (75% yield) of <Intermediate 112-3> was obtained through column purification.

(4) Preparation Example 4: Synthesis of Intermediate 112-4

Intermediate 112-3 (10 g, 0.033 mol) and 5,6-diaminopyrazine-2-carbonitrile (9.4 g, 0.070 mol) were added and stirred at 200° C. for 12 hours to react. After completion of the reaction, extraction was performed and recrystallized to give 9.2 g (74% yield) of <Intermediate 112-4>.

(5) Preparation Example 5: Synthesis of Intermediate 112-5

Intermediate 112-4 (10 g, 0.027 mol) and 5-Chloropyrazine-2,3-diamine (8.1 g, 0.056 mol) were added and stirred at 200° C. for 12 hours to react. After the reaction was completed, extraction was performed and recrystallized to give 8.5 g (70.5% yield) of <Intermediate 112-5>.

(6) Preparation Example 6: Synthesis of Intermediate 112-6

A solution of intermediate 112-5 (10 g, 0.028 mol) in 20 mL of DMF was added to potassium hydroxide (0.6 g, 0.012 mol) and stirred at 20° C. for 15 minutes. Then, Iodomethane (0.7 g, 0.005 mol) was stirred dropwise for 3 hours to react. When the reaction was complete, extraction was performed and then recrystallized to give 7.8 g (73% yield) of <Intermediate 112-6>.

(7) Preparation Example 7: Synthesis of Compound 112

Intermediate 112-6 (10 g, 0.021 mol), Dibenzofuran-3-ylboronic acid (5.3 g, 0.025 mol), potassium carbonate (8.62 g, 0.062 mol), Pd(PPh ₃ ) ₄ (1.20 g, 0.001 mol), 200 mL of toluene, 40 mL of ethanol, and 20 mL of H ₂ O were added and stirred under reflux for 5 hours to react. After completion of the reaction, extraction and column purification were performed to give 8.7 g (68% yield) of compound 112.

H-NMR (200MHz, CDCl3): δppm, 1H (9.01/s, 8.79/s, 7.95/d, 7.89/d, 7.75/d, 7.66/d, 7.64/d 7.50/s, 7.38/m, 7.32/ m) 6H (3.72/s)

LC/MS: m/z=612[(M+1) ⁺ ]

Synthesis Example 8: Synthesis of Compound 137

(1) Preparation Example 1: Synthesis of Intermediate 137-1

4,5-diaminophthalonitrile (10 g, 0.063 mol), 1,1'-carbonyldiimidazole (12.3 g, 0.076 mol), and 200 mL of DMF were added and stirred at room temperature for 24 hours to react. After completion of the reaction, extraction was performed and recrystallized to obtain 8.2 g (70% yield) of <Intermediate 137-1>.

(2) Preparation Example 2: Synthesis of Intermediate 137-2

Intermediate 137-1 (10 g, 0.054 mol), potassium hydroxide (15.2 g, 0.272 mol) H ₂ O 20 mL, 1,4-dioxane 400 mL added K ₃ Fe(CN) ₆ (53.6 g, 0.163 mol) After adding a solution (420 mL of H ₂ O) dropwise, the mixture was stirred at 100° C. for 12 hours to react. After completion of the reaction, extraction was performed and column purification was performed to obtain 3 g (yield 33%) of <Intermediate 137-2>.

(3) Preparation Example 3: Synthesis of Intermediate 137-3

Diethyl malonate (18.5 g, 0.115 mol), THF 400 mL, cooled to 0 °C, stirred, and sodium hydride (1.84 g, 0.077 mol) was slowly added dropwise and stirred for 1 hour. Intermediate 137-2 (10 g, 0.055 mol) dissolved in 60 mL of THF was added and stirred at room temperature for 12 hours to react. After completion of the reaction, extraction was performed and 13.8 g (77.5% yield) of <Intermediate 137-3> was obtained through column purification.

(4) Preparation Example 4: Synthesis of Compound 137

Intermediate 137-3 (10 g, 0.031 mol), N ² -(4-fluorophenyl)quinoxaline-2,3-diamine (32.1 g, 0.126 mol) was added and stirred at 200° C. for 12 hours to react. After completion of the reaction, extraction was performed and recrystallized to give 14.5 g (66% yield) of compound 137.

H-NMR (200MHz, CDCl3): δppm, 1H(6.0/s) 4H(7.80/d, 7.67/m, 7.60/d, 7.24/d)

LC/MS: m/z=704[(M+1) ⁺ ]

Synthesis Example 9: Synthesis of Compound 148

(1) Preparation Example 1: Synthesis of Intermediate 148-1

Intermediate 1-3 (10 g, 0.021 mol) and 4,5-bis(trifluoromethoxy)benzene-1,2-diamine (41.3 g, 0.150 mol) were added and stirred at 200° C. for 12 hours to react. After completion of the reaction, extraction was performed and recrystallized to give 16.5 g (65% yield) of <Intermediate 148-1>.

(2) Preparation Example 2: Synthesis of Compound 148

Intermediate 148-1 (10 g, 0.014 mol), 3-cyanophenylboronic (4.2 g, 0.029 mol) Copper(II) acetate monohydrate (0.6 g, 0.003 mol) and 40 mL of DMF were added and stirred at 30° C. for 24 hours to react. . After completion of the reaction, extraction was performed with Toluene, and 10.2 g (79% yield) of compound 148 was obtained through column purification.

H-NMR (200MHz, CDCl3): δppm, 2H (7.99/d, 7.86/m, 7.92/d, 7.78/d, 7.63/s, 7.5/s) 4H (7.03/s)

LC/MS: m/z=900[(M+1) ⁺ ]

Synthesis Example 10: Synthesis of Compound 175

(1) Preparation Example 1: Synthesis of Intermediate 175-1

Intermediate 38-3 (10 g, 0.031 mol) and 4,5-bis(trifluoromethoxy)benzene-1,2-diamine (34.7 g, 0.126 mol) were added and stirred at 200° C. for 12 hours to react. After completion of the reaction, extraction was performed and recrystallized to give 15.5 g (67% yield) of <Intermediate 175-1>.

(2) Preparation Example 2: Synthesis of Compound 175

Add intermediate 175-1 (10 g, 0.013 mol) and 200 mL of Anhydrous benzene, add cyanogen bromide (0.7 g, 0.007 mol), stir, and boil for at least 1 hour. Thereafter, when the reaction was completed, the mixture was cooled to 30° C., extracted, and 6.8 g (63.7% yield) of compound 175 was obtained through column purification.

H-NMR (200MHz, CDCl3): δppm, 2H (7.99/d, 7.86/m) 4H (7.03/s)

LC/MS: m/z=800[(M+1) ⁺ ]

Device Example

In an embodiment according to the present invention, the ITO transparent electrode was patterned to have a light emitting area of 2 mm × 2 mm on a glass substrate of 25 mm × 25 mm × 0.7 mm, using an ITO glass substrate with an ITO transparent electrode attached thereto. After washing. After mounting the substrate in the vacuum chamber, the base pressure was 1 × 10 ^-6 torr or more, and then the organic material and metal were deposited on the ITO in the following structure.

Device Examples 1 to 10

Using the compound according to the present invention as a doping compound for a hole transport material, a blue light emitting organic light emitting device having the following device structure was fabricated, and light emission characteristics including light emission efficiency were measured.

ITO / hole transport + p-dopant layer (5%, 5 nm) / hole transport layer (100 nm) / electron blocking layer (10 nm) / light emitting layer (20 nm) / electron transport layer (201:Liq 30 nm) / LiF ( 1 nm) / Al (100 nm)

The hole transport layer material of the ITO transparent electrode is doped with the compound according to the present invention (Chemical Formulas 1, 38, 40, 64, 74, 83, 112, 137, 148, 175) to make the hole transport + p-dopant layer 5 nm thick. The film was formed, and the hole transport layer was formed to a thickness of 100 nm using [?-NPB]. The hole blocking layer was formed to a thickness of 10 nm using [EBL1]. In addition, [BH1] was used as the host compound for the light emitting layer, and [BD1] was used as the dopant compound to form a film having a thickness of about 20 nm, and an electron transport layer (following [201] compound Liq 50% doped) An organic light emitting device was fabricated by depositing 30 nm and 1 nm of LiF and 100 nm of aluminum.

Device Comparative Example 1

The organic light-emitting device for Device Comparative Example 1 was fabricated in the same manner as in Example 1 except that the hole transport material was not doped with a p-dopant in the hole transport + p-dopant layer of the device structure.

Experimental Example 1: Light emission characteristics of device Examples 1 to 10

The organic electroluminescent device manufactured according to the above example measured voltage, current and luminous efficiency using a source meter (Model 237, Keithley) and a luminance meter (PR-650, Photo Research), and a current density of 10 mA/cm 2 The voltage to be defined as "driving voltage" was compared. The results are shown in Table 1 below.

Example P-dopant V cd/A QE(%) CIEx CIEy One Formula 1 5.43 7.13 5.50 0.135 0.134 2 Formula 38 5.49 7.21 5.64 0.134 0.134 3 Formula 40 5.59 6.96 5.45 0.135 0.135 4 Formula 64 5.54 7.16 5.79 0.133 0.132 5 Formula 74 5.40 7.08 5.68 0.134 0.133 6 Formula 83 5.53 6.94 5.55 0.134 0.134 7 Chemical Formula 112 5.60 6.91 5.50 0.135 0.135 8 Chemical Formula 137 5.36 6.96 5.78 0.134 0.134 9 Chemical Formula 148 5.39 6.93 5.73 0.135 0.135 10 Chemical Formula 175 5.57 7.11 5.92 0.134 0.133 Comparative Example 1 not used 6.03 6.51 5.37 0.137 0.136

Looking at the results shown in [Table 1], when the compound according to the present invention is applied to the device as a separate layer using the p-doped material of the hole transport material, the driving voltage is reduced compared to the conventional device (Comparative Example 1). It can be seen that the luminous efficiency and color coordinates are improved.

[α-NPB] [EBL1] [BH1] [BD1] [201]

Claims (8)

Organic light-emitting compound represented by the following [Formula I]:
[Chemical Formula Ⅰ]

In the above [Formula I],
X ₁ and X ₂ are each independently O, S or NR,
The R is hydrogen, deuterium, a halogen group, a cyano group, a substituted or unsubstituted alkyl group having 1 to 24 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 24 carbon atoms, a substituted or unsubstituted halogenated group having 1 to 24 carbon atoms It is selected from an alkyl group, a substituted or unsubstituted halogenated alkoxy group having 1 to 24 carbon atoms, a substituted or unsubstituted aryl group having 6 to 24 carbon atoms, and a substituted or unsubstituted heteroaryl group having 3 to 24 carbon atoms,
Z ₁ to Z ₆ are each independently N, or CR ₁ to CR ₆ ,
The R ₁ to R ₆ and R ₇ to R ₁₂ are each independently hydrogen, deuterium, a halogen group, a cyano group, a substituted or unsubstituted alkyl group having 1 to 24 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 24 carbon atoms , Substituted or unsubstituted alkoxy group having 1 to 24 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 24 carbon atoms, substituted or unsubstituted halogenated alkoxy group having 1 to 24 carbon atoms, substituted or unsubstituted 6 carbon atoms To 24 aryl groups or substituted or unsubstituted C3-C24 heteroaryl groups,
The R ₁ to R ₁₂ may be bonded to each other or linked with an adjacent substituent to form an alicyclic, aromatic monocyclic or polycyclic ring, and carbon atoms of the formed alicyclic, aromatic monocyclic or polycyclic ring are N, S And it may be substituted with any one or more heteroatoms selected from O. The method according to claim 1 or 2,
Each of R and R ₁ to R ₁₂ may be further substituted with one or more substituents, and the one or more substituents are deuterium, cyano group, halogen group, amino group, thiol group, hydroxy group, nitro group, C1-C24 Alkyl group, halogenated alkyl group having 1 to 24 carbon atoms, alkenyl group having 2 to 24 carbon atoms, aryl group having 6 to 24 carbon atoms, heteroaryl group having 2 to 24 carbon atoms, alkoxy group having 1 to 24 carbon atoms, halogenation of 1 to 24 carbon atoms An organic light-emitting compound, characterized in that it is selected from the group consisting of an alkoxy group, an alkylsilyl group having 1 to 24 carbon atoms, and an arylsilyl group having 6 to 24 carbon atoms. The method of claim 1,
[Chemical Formula I] is an organic light emitting compound, characterized in that selected from the following [Compound 1] to [Compound 181]:

An organic light emitting device comprising a first electrode, a second electrode, and one or more organic material layers disposed between the first electrode and the second electrode,
At least one of the organic material layers is an organic light-emitting device comprising the organic light-emitting compound of [Chemical Formula I] according to claim 1. The method of claim 4,
The organic material layer includes at least one layer selected from a hole injection layer, a hole transport layer, a layer that performs both hole injection and hole transport functions, an electron transport layer, an electron injection layer, a layer that performs electron transport and electron injection functions at the same time, and a light emitting layer,
An organic light-emitting device, wherein at least one of the layers includes an organic light-emitting compound represented by [Chemical Formula I]. The method of claim 5,
An organic light-emitting device comprising an organic light-emitting compound represented by the [Chemical Formula I] in any one layer selected from the hole transport layer and a layer that performs both hole injection and hole transport functions. The method of claim 5,
Further comprising a p-dopant layer formed adjacent to the hole transport layer or a layer that performs both hole injection and hole transport functions, wherein the p-dopant layer comprises an organic light-emitting compound represented by [Chemical Formula I] Organic light emitting device. The method of claim 6,
The hole transport layer, or a layer that performs both hole injection and hole transport functions, is characterized in that each consists of a single layer, is formed without a p-dopant doping process, and is made of an organic light emitting compound represented by the above [Formula I] Organic light-emitting device characterized by.

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