KR101694487B1 - Quinoxaline derivative compound, pyridopyrazine derivative compound and organic electroluminescent devices using the sames - Google Patents

Abstract

The present invention relates to a quinoxaline (or pyridopyrazine) derivative compound and an organic electroluminescent device using the quinoxaline (or pyridopyrazine) derivative compound, and more particularly to an organic electroluminescent device using a quinoxaline (or pyridopyrazine) A quinoxaline (or pyridopyrazine) derivative compound which can realize a low driving voltage in addition to excellent light emission characteristics, luminous efficiency, lifetime characteristics and thermal and electrical stability when used as a host (eg, red host) And an organic electroluminescent device.

Description

TECHNICAL FIELD [0001] The present invention relates to a quinoxaline derivative compound, a pyridopyrazine derivative compound, and an organic electroluminescent device using the same. BACKGROUND ART < RTI ID = 0.0 >

The present invention relates to a quinoxaline (or pyridopyrazine) derivative compound and an organic electroluminescent device using the quinoxaline (or pyridopyrazine) derivative compound, and more particularly to an organic electroluminescent device using a quinoxaline (or pyridopyrazine) A quinoxaline (or pyridopyrazine) derivative compound which can realize a low driving voltage in addition to excellent light emission characteristics, luminous efficiency, lifetime characteristics and thermal and electrical stability when used as a host (eg, red host) And an organic electroluminescent device.

As the movement toward the information society accelerates, interest in electronic devices using organic semiconductors is rapidly increasing in the information electronics industry. Therefore, over the last 10 years, development of organic materials having semiconductive properties overcoming the durability problems of organic materials has been actively carried out and various applications have been actively studied. The field of applied research using organic semiconductors such as electromagnetic wave shielding films, organic EL displays, organic thin film transistors, and solar cells continues to expand. Organic semiconductors are expected to be indispensable for future industries as they have the advantages of simple fabrication processes, low cost, breakable by impact, and the ability to implement devices on thin and flexible substrates such as paper. In particular, the development of organic displays capable of meeting these needs is an important research area.

Organic light emitting (EL) devices are attracting attention as color display devices that complement the disadvantages of currently used display devices. Due to their high efficiency, self-luminescence, low temperature processability, ) Display. Particularly, the driving life of the organic light emitting diode (OLED) has been largely solved, and the materials to be used have been diversified.

OLED is a structure in which an organic thin film is stacked between an anode and a cathode by using a characteristic of emitting organic light when a voltage is applied. When a voltage is applied to the electrode, holes injected from the transparent anode and electrons injected from the cathode recombine in the light emitting layer, and light corresponding to the energy gap generated at this time is generated. However, in a simple structure, efficiency becomes low due to a large energy difference between the layers to the light emitting region of holes and electrons. (HIL), a hole transport layer (HTL), an electron injection layer (EIL), and an electron transport layer (Electron Injection Layer) to obtain high efficiency and low driving voltage by generating a large number of excitons. Transfer Layer (ETL). In this case, holes and electrons that do not form excitons will have a leakage current, so a balanced injection is needed. In order to inject holes and electrons from the electrode, it is necessary to go beyond the energy barrier. Therefore, the anode uses ITO having a small work function and the cathode has a low work function metal (Ca / Al, Li: Al, Mg: Ag , LiF / Al, LiF: Al / Al, etc.) is used.

The light emitting material of the organic electroluminescent device OLED is divided into fluorescence and phosphorescence. The method of forming a light emitting layer includes a method of doping a fluorescent host with a dopant, and a method of doping a fluorescent host with a dopant, (DPVBi, Rubrene, DCJTB, etc.) to the light emitting body, and a method of moving the emission wavelength to a long wavelength. Such doping is intended to improve the emission wavelength, efficiency, driving voltage, lifetime, and the like.

Such a thin film structure formed by a vacuum evaporation method in a general organic electroluminescent device can adjust the moving speed of holes and electrons to balance the density of holes and electrons in the light emitting layer, thereby enhancing the luminous efficiency. In addition, in order to realize practical use and improve the characteristics of the organic electroluminescent device, the device material (for example, a light emitting layer material, a hole transporting material, etc.) must be thermally and electrically stable as well as constituting the device with a multilayer structure as described above. When a voltage is applied, a molecule having a low thermal stability due to heat generated in a device has a low crystal stability and is rearranged. As a result, local crystallization occurs, which causes deterioration and destruction of the device.

Particularly, in order to suppress the interaction at the interface in the light emitting element, it is preferable to form the light emitting layer using a bipolar organic compound having both an electron transporting property and a hole transporting property. Currently, however, most organic compounds are monopoleic materials that are biased to one side only. Therefore, it is required to develop a new bipolar organic compound having both characteristics.

Quinoxaline is an electron acceptor molecule that combines with an electron donor molecule such as an amine to form a new bandgap compound. A light emitting device using quinoxaline having excellent electron transportability exhibits a low driving voltage and excellent electrical stability.

Accordingly, the present inventors have found that when a novel compound in which a quinoxaline (or pyridopyrazine) derivative is bonded to various derivatives of electrons is used for an organic electroluminescent device, excellent luminescence characteristics and electrical stability are imparted, Efficiency, color purity, and lifespan characteristics are remarkably improved, and the present invention has been completed.

Korean Patent Publication No. 10-2004-0025986

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the prior art as described above, and it is an object of the present invention to provide a quinoxaline (or pyrido) material which can realize a high luminous efficiency and a low driving voltage, Pyrazine) derivative as a core, a method for efficiently and economically synthesizing such a heterocyclic compound, and an organic electroluminescent device using the heterocyclic compound.

In order to accomplish the above object, the present invention provides a quinoxaline (or pyridopyrazine) derivative compound having a specific structure containing quinoxaline (or pyridopyrazine) as an electron acceptor molecule.

Also, the quinoxaline (or pyridopyrazine) derivative compound is used as an organic material layer material of an organic electroluminescent device. The present invention also provides a quinoxaline (or pyridopyrazine) derivative compound.

Specifically, the quinoxaline (or pyridopyrazine) derivative compound is used as a light emitting layer material of an organic electroluminescent device, and provides a quinoxaline (or pyridopyrazine) derivative compound.

More specifically, the quinoxaline (or pyridopyrazine) derivative compound is used as a host material of a light emitting layer of an organic electroluminescent device, for example, as a red host material. The quinoxaline (or pyridopyrazine) ) Derivative compound.

According to another aspect of the present invention, there is provided an organic electroluminescent device comprising a first electrode, a second electrode, and at least one organic material layer disposed between the electrodes, wherein the at least one organic material layer includes a light emitting layer, (Or pyridopyrazine) derivative compound represented by the general formula (1).

In addition, the light emitting layer is dopant doped in the quinoxaline (or pyridopyrazine) derivative compound as a host material.

In addition, the at least one organic material layer may further include at least one layer selected from the group consisting of a hole injection layer, a hole transport layer, a hole blocking layer, an electron transport layer, and an electron injection layer.

The present invention can be applied to organic electroluminescent devices (for example, as a light emitting layer material of a multi-layered organic electroluminescent device) by combining a compound of a new structure in which a quinoxaline (or pyridopyrazine) derivative is bonded to various derivatives of electron donors, It is possible to realize excellent luminescence characteristics, electrical and thermal stability of the device, and greatly improve the driving voltage, luminous efficiency, light emission luminance, color purity and lifetime characteristics.

1 is a schematic view illustrating a single layer structure of an organic electroluminescent device according to an embodiment of the present invention.
FIG. 2 is a schematic view illustrating a multiple layer structure of an organic electroluminescent device according to another embodiment of the present invention. Referring to FIG.
3 is a graph showing the 1H NMR spectrum of the quinoxaline derivative compound 1 according to the present invention.
4 is a graph showing the thermal stability of the quinoxaline derivative compound 1 according to the present invention.

Hereinafter, the present invention will be described in detail.

Quinoxaline (or pyridopyrazine) derivative compound

The quinoxaline (or pyridopyrazine) derivative compound according to the present invention is a novel compound having a quinoxaline (or pyridopyrazine) derivative, which is an electron acceptor molecule, and a variety of electron donor derivatives, When applied to an organic material layer of a device, it can realize excellent luminescence characteristics, thermal stability and electric stability of the device, lowering the driving voltage, and significantly improving the luminous efficiency, color purity and lifetime characteristics.

When the quinoxaline (or pyridopyrazine) is combined with an electron donor molecule as an electron acceptor molecule, a new band gap is formed. The band gap at this time is a homo-energy level (HOMO energy level is determined, and the LUMO energy level is determined from the electron donor. Thus, the electron-accepting molecule newly synthesized according to the present invention has an advantage that the energy level can be easily determined.

Specifically, the quinoxaline (or pyridopyrazine) derivative compound according to the present invention is selected from the group of compounds represented by the following structural formulas and can be suitably used as an organic material layer material of an organic electroluminescent device.

Here, the organic material layer of the organic electroluminescent device may include at least one of an electroluminescence layer, a hole injection layer, a hole transport layer, a hole blocking layer, an electron transport layer, And an electron injection layer (electron injection layer).

Specifically, the quinoxaline (or pyridopyrazine) derivative compound according to the present invention exhibits excellent luminescence characteristics, and it can be applied to a light emitting layer material of an organic electroluminescence device, more specifically a host of a light emitting layer of an organic electroluminescence device, ) ≪ / RTI > material.

In addition, the quinoxaline (or pyridopyrazine) derivative compound according to the present invention may have various properties depending on the type of the substituent, in addition to the light emitting layer material. And it is expected to contribute greatly to the improvement of the display industry by providing an organic electroluminescent device having high efficiency and excellent color purity.

In addition, the quinoxaline (or pyridopyrazine) derivative compound according to the present invention can be used for a flat panel display, a planar light emitting device, a light emitting device of a surface emitting OLED for illumination, a flexible light emitting device, A backlight, a meter light source, a display plate, and the like, and organic electronic devices such as an organic solar cell (OSC), an electronic paper (e-paper), an organic photoconductor (OPC) Can act as a similar principle.

Organic field  Light emitting element

According to another aspect of the present invention, there is provided an organic electroluminescent device comprising the above quinoxaline (or pyridopyrazine) derivative compound as an organic material layer.

The organic layer of the organic electroluminescent device of the present invention may have a single layer structure of one layer or a multilayer structure of two or more layers including a light emitting layer. Here, in the case where the organic material layer has a multilayer structure, it may be a structure in which a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and the like are stacked. That is, the organic electroluminescent device of the present invention may have the structure shown in FIG. 1 (single layer structure) and FIG. 2 (multiple layer structure), but it is not limited thereto.

Specifically, the present invention comprises a first electrode (02), a second electrode (03) formed on a substrate (01), and at least one organic layer disposed between the electrodes and at least one layer of the organic layer And an organic electroluminescent device comprising the quinoxaline (or pyridopyrazine) derivative compound according to the present invention.

More specifically, the present invention is an organic electroluminescent device comprising a first electrode (02), a second electrode (03) formed on a substrate (01) and one or more organic layers disposed between the electrodes The organic layer includes the light emitting layer 06 and the light emitting layer 06 comprises the quinoxaline (or pyridopyrazine) derivative compound according to the present invention. Here, the one or more organic layers may include at least one layer selected from the group consisting of a hole injection layer 04, a hole transport layer 05, a hole blocking layer (not shown), an electron transport layer 07 and an electron injection layer 08 As shown in FIG. For example, in the organic electroluminescent device of the present invention, the organic material layer includes a hole injecting layer 04, a hole transporting layer 05, a light emitting layer 06, a hole blocking layer (not shown), an electron transporting layer 07, 08, and one or two layers of a hole injection layer 04, a hole transport layer 05, a hole blocking layer (not shown), an electron transport layer 07 and an electron injection layer 08 are formed as needed Can be used in an omitted state.

The organic electroluminescent device of the present invention can be produced by a conventional method and materials for producing an organic electroluminescent device, except that the above-described quinoxaline (or pyridopyrazine) derivative compound is used to form one or more organic layers .

For example, the organic electroluminescent device according to the present invention may be formed by depositing a metal and a conductive material on the substrate 01 by using a known PVD (Physical Vapor Deposition) method such as sputtering or e-beam evaporation A hole transporting layer 05, a light emitting layer 06, a hole blocking layer (not shown), and an electron transporting layer 07 (not shown) are formed on the anode 02 by depositing a metal oxide or an alloy thereof. And an electron injection layer 08, and then depositing a material usable as the cathode 03 on the organic layer. An organic electroluminescent device may also be manufactured by sequentially depositing a cathode 03 material, an organic material layer, and an anode 02 material on the substrate 01. Herein, the organic material layer may be formed by using a variety of polymer materials, but not by evaporation, but by using a solvent process such as spin coating, dip coating, doctor blading, screen printing, inkjet printing, Can also be produced.

As the anode material, a material having a large work function is preferably used so that hole injection can be smoothly conducted into the organic material layer. Specifically, metals such as vanadium, chromium, copper, zinc, and gold, or alloys thereof; Metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), titanium oxide (TiO), and indium zinc oxide (IZO); ZnO: Al or SnO _2: a combination of a metal and an oxide such as Sb; A conductive polymer such as poly (3-methylthiophene), poly [3,4- (ethylene-1,2-dioxy) thiophene] (PEDT), polypyrrole and polyaniline may be used, no.

As the negative electrode material, a material having a small work function is preferably used to facilitate electron injection into the organic material layer. Specifically, metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead or alloys thereof; Layer structure materials such as LiAl and LiF / Al or LiO2 / Al, but the present invention is not limited thereto.

As the hole injection layer material, it is preferable that HOMO (Highest Occupied Molecular Orbital) of the hole injection layer material be between the work function of the anode material and the HOMO of the surrounding organic layer . It is also preferable to use a material having a surface adhesion with the anode and a planarizing ability capable of alleviating the surface roughness of the anode. Materials having HOMO and LUMO (Lowest Unoccupied Molecular Orbital) values larger than the band gap of the light emitting layer and materials having high chemical stability and thermal stability are preferable. Specifically, the hole injection layer material may include at least one selected from the group consisting of metal porphyrin, oligothiophene, arylamine-based organic materials, hexanitrile hexaazatriphenylene-based organic materials, quinacridone- Perylene based organic materials, anthraquinone, polyaniline and polythiophene-based conductive polymers, but the present invention is not limited thereto.

As the hole transport layer material, a material capable of transporting holes from the anode or the hole injection layer to the light emitting layer is preferable. Materials having HOMO and LUMO values larger than the band gap of the light emitting layer and materials having high chemical stability and thermal stability are preferable. Specifically, an arylamine-based organic material, a conductive polymer, and a block copolymer having a conjugated portion and a non-conjugated portion together may be used, but the present invention is not limited thereto.

The light emitting layer material is a material capable of emitting light in a visible light region by transporting and receiving holes and electrons from the hole transporting layer and the electron transporting layer, respectively. In the present invention, the quinoxaline (or pyridopyrazine) Lt; / RTI >

In one preferred embodiment, the light emitting layer in the organic electroluminescent device of the present invention may be dopant doped with a host, for example, a quinoxaline (or pyridopyrazine) derivative compound which is a red host material. In the case of single emission, efficiency and brightness are very low, and the molecules are brought close to each other, so that excimer characteristics other than the intrinsic characteristics of each molecule can be exhibited. As a result, a dopant material is doped on a host material It is preferable to use one light-emitting layer. When the dopant material is doped on the host material, the energy generated by the excited electrons in the host material returning to the base state is absorbed by the dopant material, and the dopant material returns to the base state and emits light. Ir can be used as the dopant. For example, Ir (ppq) ₃ and Ir (phq) ₂ (acac) and Ir (ppy) ₃ may be used.

As the hole blocking layer material, a material larger than the HOMO value of the light emitting layer is preferable. Materials having high chemical stability and thermal stability are also desirable. Specifically, TPBi and BCP are mainly used, and CBP, PBD, PTCBI, and BPhen may be used, but the present invention is not limited thereto.

As the electron transport layer and the electron injection layer material, a material capable of injecting electrons from the cathode well and transferring the electrons to the light emitting layer is preferable. Materials with high chemical stability and thermal stability are also suitable. Specifically, Al complex of 8-hydroxyquinoline; Complexes containing Alq ₃ ; Organic radical compounds; Hydroxyflavone-metal complex, and the like may be used, but the present invention is not limited thereto.

The organic electroluminescent device according to the present invention may be a front emission type, a back emission type, or a both-sided emission type, depending on the material used.

Hereinafter, the present invention will be described more specifically by way of Synthesis Examples and Examples. However, these synthesis examples and examples are provided only for the understanding of the present invention, and the scope of the present invention is not limited to these examples in any sense.

Synthesis Example 1: Preparation of Compound 1

<Step 1>

To a dried round flask was added 1 eq of 2,8-dibromodibenzothiophene (15 g, 43.8 mmol), 0.04 eq of bis (triphenylphosphine) palladium (II) dichloride (1.2 g, 1.7 mmol) 0.4 mmol), and 0.4 eq of triphenylphosphine (4.6 g, 17 mmol). After the pressure was reduced, nitrogen was sufficiently charged. Triethylamine (120 ml) was added and the temperature was raised while stirring. At 50 &lt; 0 &gt; C, 2.1eq of phenylacetylene (10.11ml, 92mmol) was slowly added dropwise. Then, the mixture was stirred at 80 DEG C for 24 hours.

The resultant was cooled to room temperature, extracted with dichloromethane and distilled water, and then the organic layer was dried over anhydrous magnesium sulfate and filtered. The filtered organic layer was concentrated under reduced pressure, and the resulting mixture was purified by column chromatography with dichloromethane / hexane to obtain Compound A (7 g, 44%).

<Step 2>

In a dried round flask, 1 eq of the compound A (5 g, 13 mmol) obtained in <Step 1> was added together with 1.05 eq of iodine (3.46 g, 13.6 mmol), and after the decompression, nitrogen was sufficiently charged. Then, dimethylsulfoxide (100 ml) was added thereto, and the mixture was stirred at 155 캜 for 24 hours.

The resultant was cooled to room temperature, and water and NaHCO ₃ were added thereto. After stirring for 1 hour or longer, the powder was washed with alcohol and recrystallized from dichloromethane / hexane to obtain Compound B (5 g, 70%).

<Step 3>

In a dried round flask, 1 eq of the compound B (2 g, 4.45 mmol) obtained in <Step 2> was added together with 2.2 eq of 1,2-phenylenediamine (1.06 g, 9.8 mmol), and after the decompression, nitrogen was sufficiently charged. Then, ethanol (100 ml) was added thereto, and the mixture was stirred at 85 占 폚 for 24 hours.

The resultant was cooled to room temperature, the solvent was removed, and the residue was dissolved in dichloromethane and recrystallized to obtain Compound 1 (2 g, 77%). The &lt; 1 &gt; H NMR spectrum of Compound 1 prepared is shown in FIG.

FD-MS: m / z = 593 (C ₄₀ H ₂₄ N ₄ S = 592.71)

A graph of the thermal stability of the compound 1 prepared above is shown in FIG.

Synthesis Example 2: Preparation of Compound 2

Compound 2 was prepared in the same manner except that 3,4-diaminopyridine was used instead of 1,2-phenylene diamine in < Step 3 > of Synthesis Example 1.

FD-MS: m / z = 595.01 (C ₃₈ H ₂₂ N ₆ S = 594.69)

Synthesis Example 3: Preparation of Compound 3

Compound 3 was prepared in the same manner except that 2,3-diaminopyridine was used in place of 1,2-phenylene diamine in < Step 3 > of Synthesis Example 1.

FD-MS: m / z = 594.78 (C ₃₈ H ₂₂ N ₆ S = 594.69)

Synthesis Example 4: Preparation of Compound 4

Compound 4 was prepared in the same manner except that 3,6-diiodo-9-phenylcarbazole was used instead of 2,8-dibromodibenzothiophene in < Step 1 > of Synthesis Example 1.

FD-MS: m / z = 651.80 (C ₄₆ H ₂₉ N ₅ = 651.76)

Synthesis Example 5: Preparation of Compound 5

Compound 5 was prepared in the same manner except that 3,4-diaminopyridine was used instead of 1,2-phenylene diamine in < Step 3 > of Synthesis Example 4.

FD-MS: m / z = 653.98 (C ₄₄ H ₂₇ N ₇ = 653.73)

Synthesis Example 6: Preparation of Compound 6

Compound 6 was prepared in the same manner except that 2,3-diaminopyridine was used instead of 1,2-phenylene diamine in < Step 3 > of Synthesis Example 4.

FD-MS: m / z = 653.77 (C ₄₄ H ₂₇ N ₇ = 653.73)

Synthesis Example 7: Preparation of Compound 7

Compound 7 was prepared in the same manner except that 1,6-dibromopyrylene was used instead of 2,8-dibromodibenzothiophene in < Step 1 > of Synthesis Example 1.

FD-MS: m / z = 612.77 (C ₄₄ H ₂₈ N ₄ = 612.72)

Synthesis Example 8: Preparation of Compound 8

Compound 8 was prepared in the same manner except that 3,4-diaminopyridine was used instead of 1,2-phenylene diamine in < Step 3 > of Synthesis Example 7.

FD-MS: m / z = 614.45 (C ₄₂ H ₂₆ N ₆ = 614.7)

Synthesis Example 9: Preparation of Compound 9

Compound 9 was prepared in the same manner except that 2,3-diaminopyridine was used instead of 1,2-phenylene diamine in < Step 3 > of Synthesis Example 7.

FD-MS: m / z = 614.67 (C ₄₂ H ₂₆ N ₆ = 614.7)

Synthesis Example 10: Preparation of Compound 10

Compound 10 was prepared in the same manner except that 2,7-dibromo-9,9-spirobifluorene was used instead of 2,8-dibromodibenzothiophene in Step 1 of Synthesis Example 1 Respectively.

FD-MS: m / z = 724.88 (C ₅₃ H ₃₂ N ₄ = 724.85)

Synthesis Example 11: Preparation of Compound 11

Compound 11 was prepared in the same manner except that 3,4-diaminopyridine was used instead of 1,2-phenylene diamine in < Step 3 > of Synthesis Example 10.

FD-MS: m / z = 726.96 (C ₅₁ H ₃₀ N ₆ = 726.82)

Synthesis Example 12: Preparation of Compound 12

Compound 12 was prepared in the same manner except that 2,3-diaminopyridine was used instead of 1,2-phenylene diamine in < Step 3 > of Synthesis Example 10.

FD-MS: m / z = 726.99 (C ₅₁ H ₃₀ N ₆ = 726.82)

Synthesis Example 13: Preparation of Compound 13

In the same manner as in Synthesis Example 1 except that 2,7-dibromo-9,9-dimethyl-9H-fluorene was used instead of 2,8-dibromodibenzothiophene, compound 13 .

FD-MS: m / z = 602.75 (C ₄₃ H ₃₀ N ₄ = 602.73)

Synthesis Example 14: Preparation of Compound 14

Compound 14 was prepared in the same manner except that 3,4-diaminopyridine was used instead of 1,2-phenylene diamine in < Step 3 > of Synthesis Example 13.

FD-MS: m / z = 605.10 (C ₄₁ H ₂₈ N ₆ = 604.7)

Synthesis Example 15: Preparation of Compound 15

Compound 15 was prepared in the same manner except that 2,3-diaminopyridine was used instead of 1,2-phenylene diamine in < Step 3 > of Synthesis Example 13.

FD-MS: m / z = 604.66 (C ₄₁ H ₂₈ N ₆ = 604.7)

Example 1: Fabrication of organic electroluminescent device

Before the deposition for the device fabrication, a glass substrate coated with a thin film of ITO (Indium Tin Oxide) at a thickness of 1500Å was cleaned (impurities and fine particles on the surface were deformed by organic substances, deterioration of interfacial properties between ITO and organic materials, A phenomenon in which light is not partially or totally caused due to burning of impurities at the time of contact, defective contact with ITO, and shortening of the lifetime of the device). In order to remove impurities such as organic substances, ionic substances, and metallic substances present on the substrate before the organic material deposition, the substrate was removed by ultrasonic cleaning for 5 minutes at room temperature with acetone, and then 5 parts by IPA (Isopropyl alcohol) Ultrasonic cleaning was performed for a minute and then dried using N ₂ gas.

HAT-CN, which is a hole injection layer, was vacuum deposited on the prepared ITO transparent electrode to a thickness of 100 Å and a hole transport material TAPC was vacuum deposited thereon to a thickness of 600 Å. Then, an Ir compound (Ir (mphmq2 (acac)) was vacuum deposited to a thickness of 300 Å. A BmPyPb was vacuum deposited as an electron transport layer to a thickness of 500 Å. Lithium fluoride (LiF) and aluminum The deposition rate of the organic material was 1 Å / sec, the deposition rate of lithium fluoride was 0.1 Å / sec, and the deposition rate of aluminum was 1 Å / sec.

The characteristics such as the driving voltage (1Cd / m &lt; ² &gt;) of the thus fabricated organic electroluminescent device, the luminescence brightness at a current density of 10 mA / cm &lt; ² &gt; and the luminescent efficiency are shown in Table 1 below.

Example 2: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that Compound 2 obtained in Synthesis Example 2 was used as the light emitting layer HOST.

The characteristics of the organic electroluminescent device such as the driving voltage (1Cd / m ² ), the luminescence brightness at a current density of 10 mA / cm ² , the luminous efficiency, and the like are shown in Table 1 below.

Example 3: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that Compound 4 obtained in Synthesis Example 4 was used as the light emitting layer HOST.

The characteristics of the organic electroluminescent device such as the driving voltage (1Cd / m ² ), the luminescence brightness at a current density of 10 mA / cm ² , the luminous efficiency, and the like are shown in Table 1 below.

Example 4: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that Compound 6 obtained in Synthesis Example 6 was used as the light emitting layer HOST.

The characteristics of the organic electroluminescent device such as the driving voltage (1Cd / m ² ), the luminescence brightness at a current density of 10 mA / cm ² , the luminous efficiency, and the like are shown in Table 1 below.

Example 5: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that Compound 10 obtained in Synthesis Example 10 was used as the light emitting layer HOST.

The characteristics of the organic electroluminescent device such as the driving voltage (1Cd / m ² ), the luminescence brightness at a current density of 10 mA / cm ² , the luminous efficiency, and the like are shown in Table 1 below.

Example 6: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that the compound 11 obtained in Synthesis Example 11 was used as the light emitting layer HOST.

The characteristics of the organic electroluminescent device such as the driving voltage (1Cd / m ² ), the luminescence brightness at a current density of 10 mA / cm ² , the luminous efficiency, and the like are shown in Table 1 below.

Example 7: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that the compound 13 obtained in Synthesis Example 13 was used as the light emitting layer HOST.

The characteristics of the organic electroluminescent device such as the driving voltage (1Cd / m ² ), the luminescence brightness at a current density of 10 mA / cm ² , the luminous efficiency, and the like are shown in Table 1 below.

Comparative Example 1: Fabrication of organic electroluminescent device

(Carbazole-9-yl) biphenyl (CBP) represented by the following chemical formula was used as the light emitting layer HOST, an organic electroluminescent device was fabricated in the same manner as in Example 1.

The characteristics of the organic electroluminescent device such as the driving voltage (1Cd / m ² ), the luminescence brightness at a current density of 10 mA / cm ² , the luminous efficiency, and the like are shown in Table 1 below.

 [Table 1]

As shown in Table 1, when an organic electroluminescent device is fabricated using the quinoxaline (or pyridopyrazine) derivative compound according to the present invention as a light emitting layer material, a low voltage, high efficiency, It is possible to realize various characteristics required for an organic electroluminescent device such as high brightness and thermal stability in a harmonized manner.

01: substrate
02: anode (or first electrode)
03: cathode (or second electrode)
04: Hole injection layer
05: Hole transport layer
06: light emitting layer
07: Electron transport layer
08: Electron injection layer

Claims (8)

A pyridopyrazine derivative compound selected from the group of compounds represented by the structural formula:

.
The method according to claim 1,
Wherein the pyridopyrazine derivative compound is used as an organic material layer material of an organic electroluminescent device.
3. The method of claim 2,
Wherein the pyridopyrazine derivative compound is used as a light emitting layer material of an organic electroluminescent device.
The method of claim 3,
Wherein the pyridopyrazine derivative compound is used as a host material of the light emitting layer of the organic electroluminescent device.
5. The method of claim 4,
Wherein the pyridopyrazine derivative compound is used as a red host material of the light emitting layer of the organic electroluminescent device.
1. An organic electroluminescent device comprising a first electrode, a second electrode, and at least one organic material layer disposed between the electrodes,
Wherein the one or more organic layers include a light emitting layer,
Wherein the light emitting layer comprises the pyridopyrazine derivative compound according to any one of claims 1 to 5.
The method according to claim 6,
Wherein the light emitting layer is doped with a dopant to the pyridopyrazine derivative compound as a host material.
The method according to claim 6,
Wherein the at least one organic material layer further comprises at least one layer selected from the group consisting of a hole injection layer, a hole transport layer, a hole blocking layer, an electron transport layer, and an electron injection layer.

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