WO2015009076A1

WO2015009076A1 - A combination of a dopant compound and a host compound and an organic electroluminescent device comprising the same

Info

Publication number: WO2015009076A1
Application number: PCT/KR2014/006496
Authority: WO
Inventors: Young-Gil Kim; Hyo-Jung Lee; Jin-Hee Kim; Jeong-Hwan Jeon; Chi-Sik Kim; Young-Jun Cho; Kyung-Joo Lee
Original assignee: Rohm And Haas Electronic Materials Korea Ltd.
Priority date: 2013-07-17
Filing date: 2014-07-17
Publication date: 2015-01-22
Also published as: KR20150010016A; CN105359292A

Abstract

The present invention relates to a specific combination of a dopant compound comprising an amino-pyrene and a host compound comprising a di-aryl subsituted anthracene, and an organic electroluminescent device comprising the same. The organic electroluminescent device of the present invention provides the advantages of remarkable luminous efficiency, excellent color purity, low driving voltage, and good operational lifespan.

Description

A COMBINATION OF A DOPANT COMPOUND AND A HOST COMPOUND AND AN ORGANIC ELECTROLUMINESCENT DEVICE COMPRISING THE SAME

The present invention relates to a combination of a dopant compound and a host compound, and an organic electroluminescent device comprising the same.

An electroluminescent device (EL device) is a self-light-emitting device which has advantages in that it provides a wider viewing angle, a greater contrast ratio, and a faster response time. An organic EL device was first developed by Eastman Kodak, by using small aromatic diamine molecules and aluminum complexes as materials for forming a light-emitting layer [Appl. Phys. Lett. 51, 913, 1987].

An organic EL device can reduce production cost and material cost, and has advantages in that it provides a wider viewing angle, a greater contrast ratio, and a faster response time compared to liquid crystal devices (LCD). Organic EL devices have been remarkably developed to have over 80 times more efficiency and over 100 times more lifespan since they first came out.

In addition, organic EL devices are favorable for display widening, and so display widening is rapidly in progress, e.g. a 40-inch organic EL device panel is presented. For display widening, longer lifespan and improved luminous efficiency of the device are desired.

For improving the lifespan of an organic EL device, preventing material crystallization caused by Joule heat generated during device operation is needed. Accordingly, it is desired to develop an organic compound having excellent electron injection and mobility, and high electrochemical stability.

The most important factor determining luminous efficiency of an organic EL device is the light-emitting material. The light-emitting materials are categorized as fluorescence which is the use of an exciton in a singlet state; and phosphorescence which is the use of an exciton in a triplet state. In general, the organic EL devices using phosphorescent materials have short lifespan, and thus fluorescent materials have been widely used until now.

In addition, a host/dopant system may be used as light-emitting materials. When using only one substance as a light-emitting material, the maximum emission wavelength shifts to a longer wavelength due to interactions between molecules, and problems are occurred such as decrease of color purity or device efficiency drop due to the attenuation effect of light emission. A host/dopant system is advantageous for increasing color purity, luminous efficiency due to energy transfer, and stability.

For blue fluorescent host materials, many materials have been researched and commercialized after the development of 4,4'-bis(2,2'-diphenylvinyl)-1,1'-biphenyl (DPVBi) from Idemitsu Kosan. Although the blue material system of Idemitsu Kosan and the dinaphthylanthracene, tetra(t-butyl)perylene system of Kodak are known, much research has been conducted until now to develop blue fluorescent host materials that can provide better characteristics in the device.

As for fluorescent dopants, compounds such as amine-based compounds, aromatic compounds, chelate complexes such as tris(8-quinolinolate)aluminum complexes, coumarin derivatives, tetraphenylbutadiene derivatives, bisstyrylarylene derivatives, and oxadiazole derivatives can be selected for desired emission color.

Meanwhile, when applying light-emitting materials containing a conventional dopant compound and a host compound to an organic EL device, unsatisfactory results in luminous efficiency, power efficiency, operational lifespan, etc., are shown. In particular, it is difficult to obtain a blue light-emitting layer having excellent lifespan characteristics.

The first objective of the present invention is to provide an organic EL device in which an organic layer is inserted between an anode and a cathode on a substrate wherein the organic layer comprises a light-emitting layer comprising a combination of one or more dopant compounds and one or more host compounds. The second is to provide an organic EL device having high luminous efficiency, excellent color purity, low driving voltage, and good operational lifespan.

In order to achieve the above objective, the present invention provides a combination of one or more host compounds represented by the following formula 1, and one or more dopant compounds represented by the following formula 2, and an organic EL device comprising the same:

wherein

R₁to R₁₈ each independently represent hydrogen, deuterium, a halogen, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C3-C30)cycloalkyl, a substituted or unsubstituted (C1-C30)alkoxy, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, -SiR₃₁R₃₂R₃₃, a cyano or a hydroxyl; or R₁ to R₅, and R₁₄ to R₁₈ are linked to an adjacent substituent(s) to form a mono- or polycyclic, substituted or unsubstituted (3- to 30-membered) alicyclic or aromatic ring in which the carbon atom of the ring may form a spiro structure, and the carbon atom(s) of the ring may be replaced with at least one hetero atom selected from nitrogen, oxygen and sulfur;

R₃₁ to R₃₃ each independently represent hydrogen, deuterium, a halogen, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl;

Ar₁ and Ar₂ each independently represent hydrogen, deuterium, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl; or are linked to an adjacent substituent(s) to form a mono- or polycyclic, substituted or unsubstituted (3- to 30-membered) alicyclic or aromatic ring in which the carbon atom of the ring may form a spiro structure, and the carbon atom(s) of the ring may be replaced with at least one hetero atom selected from nitrogen, oxygen and sulfur; where Ar₁and Ar₂ are not simultaneously hydrogen; and

the heteroaryl contains at least one hetero atom selected from B, N, O, S, P(=O), Si and P;

wherein

Ar₃ represents a substituted or unsubstituted pyrene;

L represents a single bond, a substituted or unsubstituted (C6-C30)arylene, or a substituted or unsubstituted (3- to 30-membered)heteroarylene;

Ar₄and Ar₅ each independently represent a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl; or Ar₄ and Ar₅ are linked with the nitrogen atom to form a mono- or polycyclic, substituted or unsubstituted (3- to 30-membered) alicyclic or aromatic ring, whose carbon atom(s) may be replaced with at least one hetero atom selected from nitrogen, oxygen and sulfur; and

n represents an integer of 1 to 3; where n is 2 or more, each of

are same or different.

By comprising the specific combination of a dopant compound and a host compound according to the present invention, it is possible to provide an organic EL device with high luminous efficiency, excellent color purity, low driving voltage, and good operational lifespan.

Hereinafter, the present invention will be described in detail. However, the following description is intended to explain the invention, and is not meant in any way to restrict the scope of the invention.

The present invention relates to an organic electroluminescent device comprising a combination of one or more host compounds represented by formula 1, and one or more dopant compounds represented by formula 2.

The compounds represented by the above formulae 1 and 2 will be described in detail.

Herein, “alkyl” includes methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, etc.; “alkenyl” includes vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 2-methylbut-2-enyl, etc.; “alkynyl” includes ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-methylpent-2-ynyl, etc.; “cycloalkyl” includes cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, etc.; “5- to 7-membered heterocycloalkyl” is a cycloalkyl having at least one heteroatom selected from B, N, O, S, P(=O), Si and P, preferably O, S and N, and 5 to 7 ring backbone atoms, and includes tetrahydrofuran, pyrrolidine, thiolan, tetrahydropyran, etc.; “aryl(ene)” is a monocyclic or fused ring derived from an aromatic hydrocarbon, and includes phenyl, biphenyl, terphenyl, naphthyl, binaphthyl, phenylnaphthyl, naphthylphenyl, fluorenyl, phenylfluorenyl, benzofluorenyl, dibenzofluorenyl, phenanthrenyl, phenylphenanthrenyl, anthracenyl, indenyl, indanyl, triphenylenyl, pyrenyl, tetracenyl, perylenyl, chrysenyl, naphthacenyl, fluoranthenyl, etc.; “3- to 30-membered heteroaryl(ene)” is an aryl group having at least one, preferably 1 to 4 heteroatom selected from the group consisting of B, N, O, S, P(=O), Si and P, and 3 to 30 ring backbone atoms; is a monocyclic ring, or a fused ring condensed with at least one benzene ring; may be partially saturated; may be one formed by linking at least one heteroaryl or aryl group to a heteroaryl group via a single bond(s); and includes a monocyclic ring-type heteroaryl such as furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl, triazolyl, tetrazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, etc., and a fused ring-type heteroaryl such as benzofuranyl, benzothiophenyl, isobenzofuranyl, dibenzofuranyl, dibenzothiophenyl, benzoimidazolyl, benzothiazolyl, benzoisothiazolyl, benzoisoxazolyl, benzoxazolyl, isoindolyl, indolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, carbazolyl, phenoxazinyl, phenanthridinyl, benzodioxolyl, etc. Further, “halogen” includes F, Cl, Br and I.

Herein, “substituted” in the expression “substituted or unsubstituted” means that a hydrogen atom in a certain functional group is replaced with another atom or group, i.e., a substituent. The substituents of the substituted alkyl, the substituted cycloalkyl, the substituted alkoxy, the substituted aryl, the substituted heteroaryl, the substituted pyrene, the substituted arylene, the substituted heteroarylene, the substituted mono- or polycyclic, alicyclic or aromatic ring in R₁ to R₁₈, R₃₁ to R₃₃, Ar₁ to Ar₅, and L in the above formulae 1 and 2 each independently are at least one selected from the group consisting of deuterium, a halogen, a (C1-C30)alkyl, a (C1-C30)alkyl substituted with a halogen, a (C1-C30)alkoxy, a (C6-C30)aryl, a (C6-C30)aryl substituted with a (3- to 30-membered)heteroaryl, a (C6-C30)aryl substituted with deuterium, a (3- to 30-membered)heteroaryl, a (3- to 30-membered)heteroaryl substituted with a (C6-C30)aryl, a (3- to 30-membered)heteroaryl substituted with a (C1-C30)alkyl(C6-C30)aryl, a (C3-C30)cycloalkyl, a (5- to 7-membered)heterocycloalkyl, a tri(C1-C30)alkylsilyl, a tri(C6-C30)arylsilyl, a di(C1-C30)alkyl(C6-C30)arylsilyl, a (C1-C30)alkyldi(C6-C30)arylsilyl, a (C2-C30)alkenyl, a (C2-C30)alkynyl, a cyano, a mono- or di- (C1-C30)alkylamino, a mono- or di- (C6-C30)arylamino, a (C1-C30)alkyl(C6-C30)arylamino, a di(C6-C30)arylboronyl, a di(C1-C30)alkylboronyl, a (C1-C30)alkyl(C6-C30)arylboronyl, a (C6-C30)aryl(C1-C30)alkyl, a (C1-C30)alkyl(C6-C30)aryl, a carboxyl, a nitro, and a hydroxyl, and preferably each independently are at least one selected from the group consisting of deuterium, a halogen, a (C1-C6)alkyl, a (C1-C6)alkyl substituted with a halogen, a (C1-C6)alkoxy, a (C6-C15)aryl, a (C6-C15)aryl substituted with deuterium, a (5- to 15-membered)heteroaryl, a (5- to 15-membered)heteroaryl substituted with a (C6-C15)aryl, a (5- to 15-membered)heteroaryl substituted with a (C1-C6)alkyl(C6-C15)aryl, a tri(C1-C6)alkylsilyl, a tri(C6-C15)arylsilyl, a (C1-C6)alkyldi(C6-C15)arylsilyl, a cyano, a (C1-C6)alkyl(C6-C15)aryl, and a hydroxyl.

In formula 1 above, R₁ to R₁₈ preferably, each independently represent hydrogen, deuterium, a halogen, a substituted or unsubstituted (C1-C10)alkyl, a substituted or unsubstituted (C6-C20)aryl, or a substituted or unsubstituted (5- to 20-membered)heteroaryl; or R₁to R₅ are linked to an adjacent substituent(s) to form a mono- or polycyclic, substituted or unsubstituted (5- to 20-membered) alicyclic or aromatic ring which may form a spiro structure, and more preferably, each independently represent hydrogen, deuterium, a halogen, a (C1-C6)alkyl, a (C6-C15)aryl, or a (5- to 15-membered)heteroaryl; or R₁ to R₅ are linked to an adjacent substituent(s) to form a mono- or polycyclic, (5- to 15-membered) alicyclic or aromatic ring unsubstituted or substituted with a methyl or a phenyl, which may form a spiro fluorene structure.

In formula 1 above, Ar₁ and Ar₂ preferably, each independently represent a substituted or unsubstituted (C6-C20)aryl, or a substituted or unsubstituted (5- to 20-membered)heteroaryl, and more preferably, each independently represent a (C6-C18)aryl unsubstituted or substituted with deuterium, a halogen, a (C1-C6)alkyl, a (C6-C15)aryl, a (5- to 15-membered)heteroaryl, or a (C1-C6)alkyl(C6-C15)aryl; or a (5- to 15-membered)heteroaryl unsubstituted or substituted with a (C6-C15)aryl.

In formula 2 above, Ar₃ preferably represents a pyrene unsubstituted or substituted with a (C1-C6)alkyl, a (C6-C15)aryl, a (C6-C15)aryl substituted with deuterium, a (5- to 15-membered)heteroaryl substituted with a (C6-C15)aryl, or a (5- to 15-membered)heteroaryl substituted with a (C1-C6)alkyl(C6-C15)aryl.

Ar₃ is preferably selected from the following structures:

wherein A represents deuterium, a halogen, a (C1-C30)alkyl, a (C1-C30)alkyl substituted with a halogen, a (C1-C30)alkoxy, a (C6-C30)aryl, a (C6-C30)aryl substituted with a (3- to 30-membered)heteroaryl, a (C6-C30)aryl substituted with deuterium, a (3- to 30-membered)heteroaryl, a (3- to 30-membered)heteroaryl substituted with a (C6-C30)aryl, a (3- to 30-membered)heteroaryl substituted with a (C1-C30)alkyl(C6-C30)aryl, a (C3-C30)cycloalkyl, a (5- to 7-membered)heterocycloalkyl, a tri(C1-C30)alkylsilyl, a tri(C6-C30)arylsilyl, a di(C1-C30)alkyl(C6-C30)arylsilyl, a (C1-C30)alkyldi(C6-C30)arylsilyl, a (C2-C30)alkenyl, a (C2-C30)alkynyl, a cyano, a mono- or di- (C1-C30)alkylamino, a mono- or di- (C6-C30)arylamino, a (C1-C30)alkyl(C6-C30)arylamino, a di(C6-C30)arylboronyl, a di(C1-C30)alkylboronyl, a (C1-C30)alkyl(C6-C30)arylboronyl, a (C6-C30)aryl(C1-C30)alkyl, a (C1-C30)alkyl(C6-C30)aryl, a carboxyl, a nitro, or a hydroxyl; and m represents an integer of 0 to 4. A preferably represents a (C1-C6)alkyl, a (C6-C15)aryl, a (C6-C15)aryl substituted with deuterium, a (5- to 15-membered)heteroaryl substituted with a (C6-C15)aryl, or a (5- to 15-membered)heteroaryl substituted with a (C1-C6)alkyl(C6-C15)aryl.

In formula 2 above, L preferably represents a single bond, or a substituted or unsubstituted (C6-C20)arylene, and more preferably represents a single bond, or a (C6-C15)arylene unsubstituted or substituted with a (C1-C6)alkyl.

In formula 2 above, Ar₄ and Ar₅ preferably, each independently represent a substituted or unsubstituted (C6-C20)aryl, or a substituted or unsubstituted (5- to 20-membered)heteroaryl; or Ar₄ and Ar₅ are linked with the nitrogen atom to form a mono- or polycyclic, substituted or unsubstituted (5- to 20-membered) alicyclic or aromatic ring, and more preferably, each independently represent a (C6-C18)aryl unsubstituted or substituted with deuterium, a halogen, a (C1-C6)alkyl, a (C1-C6)alkyl substituted with a halogen, a (C1-C6)alkoxy, a (C6-C15)aryl, a tri(C1-C6)alkylsilyl, a tri(C6-C15)arylsilyl, a (C1-C6)alkyldi(C6-C15)arylsilyl, a cyano, or a hydroxyl; or a (5- to 15-membered)heteroaryl unsubstituted or substituted with a (C6-C15)aryl; or Ar₄ and Ar₅ are linked with the nitrogen atom to form a polycyclic, (5- to 15-membered) alicyclic or aromatic ring unsubstituted or substituted with a halogen, a cyano, a (C1-C6)alkyl, a (C6-C15)aryl, or a cyano(C6-C15)aryl.

Ar₄ and Ar₅ may be linked with the nitrogen atom to form a ring selected from the following structures:

The specific compounds of formula 1 include the following compounds, but are not limited thereto:

The specific compounds of formula 2 include the following compounds, but are not limited thereto:

The compounds of formulae 1 and 2 according to the present invention can be prepared by a synthetic method known to a person skilled in the art.

The organic electroluminescent device comprises a first electrode, a second electrode, and at least one organic layer between the first and second electrodes. The organic layer comprises a light-emitting layer, and the light-emitting layer comprises the combination of one or more host compounds represented by formula 1, and one or more dopant compounds represented by formula 2.

One of the first and second electrodes may be an anode, and the other may be a cathode. The organic layer may further comprise at least one layer selected from the group consisting of a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, an interlayer, a hole blocking layer, and an electron blocking layer.

The light-emitting layer is a layer which emits light, and it may be a single layer, or it may be a multi layer of which two or more layers are laminated. The light-emitting layer can also inject/transport electrons/holes, besides emitting light. The dopant is preferably doped in a concentration of less than 17 wt%, based on the total amount of the dopant and host of the light-emitting layer.

In another embodiment of the present invention, a host/dopant combination of one or more host compounds represented by formula 1, and one or more dopant compounds represented by formula 2 is provided. In addition, an organic EL device comprising the host/dopant combination is also provided.

In another embodiment, the present invention provides an organic electroluminescent material comprising the host/dopant combination of one or more host compounds represented by formula 1, and one or more dopant compounds represented by formula 2, and an organic EL device comprising the material. The above material can be comprised of the combination of a compound of formula 1 and a compound of formula 2 alone, or can further include conventional materials generally used in organic electroluminescent materials.

In another embodiment, the present invention provides an organic layer comprising the combination of one or more host compounds represented by formula 1, and one or more dopant compounds represented by formula 2. The organic layer comprises plural layers. The dopant compound and the host compound can be comprised in the same layer, or can be comprised in different layers. In addition, the present invention provides an organic EL device comprising the organic layer.

The organic layer of the organic EL device according to the present invention may further comprise, in addition to the combination of a host compound of formula 1 and a dopant compound of formula 2, at least one compound selected from the group consisting of arylamine-based compounds and styrylarylamine-based compounds.

In the organic EL device according to the present invention, the organic layer may further comprise at least one metal selected from the group consisting of metals of Group 1, metals of Group 2, transition metals of the 4^th period, transition metals of the 5^th period, lanthanides and organic metals of d-transition elements of the Periodic Table, or at least one complex compound comprising said metal. The organic layer may further comprise one or more additionally comprised light-emitting layer and a charge generating layer.

In addition, the organic EL device according to the present invention may emit white light by further comprising at least one light-emitting layer which comprises a blue electroluminescent compound, a red electroluminescent compound or a green electroluminescent compound known in the field, besides the compound according to the present invention. Also, if needed, a yellow or orange light-emitting layer can be comprised in the device.

According to the present invention, at least one layer (hereinafter, "a surface layer”) is preferably placed on an inner surface(s) of one or both electrode(s); selected from a chalcogenide layer, a metal halide layer and a metal oxide layer. Specifically, a chalcogenide(includes oxides) layer of silicon or aluminum is preferably placed on an anode surface of an electroluminescent medium layer, and a metal halide layer or a metal oxide layer is preferably placed on a cathode surface of an electroluminescent medium layer. Such a surface layer provides operation stability for the organic electroluminescent device. Preferably, said chalcogenide includes SiO_X(1≤X≤2), AlO_X(1≤X≤1.5), SiON, SiAlON, etc.; said metal halide includes LiF, MgF₂, CaF₂, a rare earth metal fluoride, etc.; and said metal oxide includes Cs₂O, Li₂O, MgO, SrO, BaO, CaO, etc.

In the organic EL device according to the present invention, a mixed region of an electron transport compound and an reductive dopant, or a mixed region of a hole transport compound and an oxidative dopant is preferably placed on at least one surface of a pair of electrodes. In this case, the electron transport compound is reduced to an anion, and thus it becomes easier to inject and transport electrons from the mixed region to an electroluminescent medium. Further, the hole transport compound is oxidized to a cation, and thus it becomes easier to inject and transport holes from the mixed region to the electroluminescent medium. Preferably, the oxidative dopant includes various Lewis acids and acceptor compounds; and the reductive dopant includes alkali metals, alkali metal compounds, alkaline earth metals, rare-earth metals, and mixtures thereof. A reductive dopant layer may be employed as a charge generating layer to prepare an electroluminescent device having two or more electroluminescent layers and emitting white light.

In order to form each layer of the organic EL device according to the present invention, dry film-forming methods such as vacuum evaporation, sputtering, plasma and ion plating methods, or wet film-forming methods such as spin coating, dip coating, and flow coating methods can be used.

When using a wet film-forming method, a thin film can be formed by dissolving or diffusing materials forming each layer into any suitable solvent such as ethanol, chloroform, tetrahydrofuran, dioxane, etc. The solvent can be any solvent where the materials forming each layer can be dissolved or diffused, and where there are no problems in film-formation capability.

Hereinafter, the compound of the present invention, the preparation method of the compound, and the luminescent properties of the device will be explained in detail with reference to the following examples. However, these are just for exemplifying the embodiment of the present invention, so the scope of the present invention cannot be limited thereto.

Example 1: Preparation of compound H-26

Preparation of compound 1-2

After mixing compound 1-1 (25 g, 0.157 mol) and HCl (10%, 840 mL) in a flask, the mixture was stirred at 0°C. NaNO₂(11.6 g, 0.168 mol) was then dissolved in H₂O 85 mL, and added to the reaction mixture, and the mixture was stirred for 20 minutes at 0°C. KI (52 g, 0.314 mol) was then dissolved in H₂O 165 mL and added to the reaction mixture, and the mixture was stirred at 0°C for 3 hours. After the reaction, the mixture was washed with distilled water and extracted with ethylacetate (EA). The organic layer was then dried with MgSO₄, the solvent was removed using a rotary evaporator, and the remaining substance was then purified with column chromatography to obtain compound 1-2 (10.2 g, 24%).

Preparation of compound 1-4

After introducing compound 1-2 (9.2 g, 0.034 mol) in a flask, and adding compound 1-3 (11 g, 0.037 mol), Pd(PPh₃)₄ (2.0 g, 0.001 mol), K₂CO₃ (2 M, 51 mL), EtOH 51 mL, and toluene 100 mL, the reaction mixture was heated to 120°C and stirred for 8 hours. After the reaction, the mixture was washed with distilled water and extracted with EA. The organic layer was then dried with MgSO₄, the solvent was removed using a rotary evaporator, and the remaining substance was then purified with column chromatography to obtain compound 1-4 (9.5 g, 70%).

Preparation of compound 1-5

After mixing compound 1-4 (9.5 g, 0.024 mol) and methylenechloride (MC) 200 mL in a flask, the reaction mixture was stirred at 0°C for 20 minutes. Triethylamine (10 mL, 0.072 mol) was then added to the reaction mixture. Trifluoromethanesulfonic anhydride (OTf₂) (5.1 mL, 0.031 mol) was then added to the mixture and stirred at room temperature for 6 hours. After the reaction, 4 M HCl was added to the mixture, the mixture was washed with distilled water and extracted with EA. The organic layer was then dried with MgSO₄, the solvent was removed using a rotary evaporator, and the remaining substance was then purified with column chromatography to obtain compound 1-5 (8.0 g, 63%).

Preparation of compound H-26

After introducing compound 1-5 (8.0 g, 0.015 mol) in a flask, and adding compound 1-6 (2.0 g, 0.016 mol), Pd(PPh₃)₄ (1.0 g, 0.001 mol), K₂CO₃ (2 M, 22 mL), EtOH 22 mL, and toluene 50 mL, the reaction mixture was heated to 120°C and stirred for 8 hours. After the reaction, the mixture was washed with distilled water and extracted with EA. The organic layer was then dried with MgSO₄, the solvent was removed using a rotary evaporator, and the remaining substance was then purified with column chromatography to obtain compound H-26 (3.1 g, 45%).

Example 2: Preparation of compound H-47

After introducing compound 1-5 (3.7 g, 0.007 mol) of Example 1 in a flask, and adding compound 2-1 (2.7 g, 0.007 mol), Pd(PPh₃)₄ (465 mg, 0.0004 mol), K₂CO₃(2 M, 11 mL), EtOH 11 mL, and toluene 22 mL, the reaction mixture was heated to 120°C and stirred for 8 hours. After the reaction, the mixture was washed with distilled water and extracted with EA. The organic layer was then dried with MgSO₄, the solvent was removed using a rotary evaporator, and the remaining substance was then purified with column chromatography to obtain compound H-47 (3.3 g, 78%).

Example 3: Preparation of compound H-48

After introducing compound 1-5 (3.7 g, 0.006 mol) of Example 1 in a flask, and adding compound 3-1 (1.3 g, 0.006 mol), Pd(PPh₃)₄ (350 mg, 0.0003 mol), K₂CO₃ (2 M, 10 mL), EtOH 10 mL, and toluene 20 mL, the reaction mixture was heated to 120°C and stirred for 8 hours. After the reaction, the mixture was washed with distilled water and extracted with EA. The organic layer was then dried with MgSO₄, the solvent was removed using a rotary evaporator, and the remaining substance was then purified with column chromatography to obtain compound H-48 (1.8 g, 48%).

Example 4: Preparation of compound H-45

After introducing compound 1-5 (4.0 g, 0.007 mol) of Example 1 in a flask, and adding compound 4-1 (1.6 g, 0.008 mol), Pd(PPh₃)₄ (462 mg, 0.0004 mol), K₂CO₃ (2 M, 11 mL), EtOH 11 mL, and toluene 22 mL, the reaction mixture was heated to 120°C and stirred for 8 hours. After the reaction, the mixture was washed with distilled water and extracted with EA. The organic layer was then dried with MgSO₄, the solvent was removed using a rotary evaporator, and the remaining substance was then purified with column chromatography to obtain compound H-45 (1.7 g, 43%).

Example 5: Preparation of compound H-49

After introducing compound 1-5 (3.0 g, 0.005 mol) of Example 1 in a flask, and adding compound 5-1 (1.5 g, 0.006 mol), Pd(PPh₃)₄ (330 mg, 0.0002 mol), K₂CO₃ (2 M, 9 mL), EtOH 9 mL, and toluene 22 mL, the reaction mixture was heated to 120°C and stirred for 8 hours. After the reaction, the mixture was washed with distilled water and extracted with EA. The organic layer was then dried with MgSO₄, the solvent was removed using a rotary evaporator, and the remaining substance was then purified with column chromatography to obtain compound H-49 (2.0 g, 60%).

Example 6: Preparation of compound H-1

After introducing compound 6-1 (5.4 g, 0.010 mol) in a flask, and adding compound 1-6 (1.4 g, 0.011 mol), Pd(PPh₃)₄ (580 mg, 0.0005 mol), K₂CO₃ (2 M, 15 mL), EtOH 15 mL, and toluene 30 mL, the reaction mixture was heated to 120°C and stirred for 8 hours. After the reaction, the mixture was washed with distilled water and extracted with EA. The organic layer was then dried with MgSO₄, the solvent was removed using a rotary evaporator, and the remaining substance was then purified with column chromatography to obtain compound H-1 (3.3 g, 73%).

Example 7: Preparation of compound H-19

After introducing compound 6-1 (4.0 g, 0.007 mol) of Example 6 in a flask, and adding compound 4-1 (1.6 g, 0.008 mol), Pd(PPh₃)₄(462 mg, 0.0004 mol), K₂CO₃ (2 M, 11 mL), EtOH 11 mL, and toluene 22 mL, the reaction mixture was heated to 120°C and stirred for 8 hours. After the reaction, the mixture was washed with distilled water and extracted with EA. The organic layer was then dried with MgSO₄, the solvent was removed using a rotary evaporator, and the remaining substance was then purified with column chromatography to obtain compound H-19 (2.7 g, 67%).

Example 8: Preparation of compound H-20

After introducing compound 6-1 (3.0 g, 0.005 mol) of Example 6 in a flask, and adding compound 5-1 (1.8 g, 0.008 mol), Pd(PPh₃)₄ (330 mg, 0.0003 mol), K₂CO₃(2 M, 10 mL), EtOH 10 mL, and toluene 20 mL, the reaction mixture was heated to 120°C and stirred for 8 hours. After the reaction, the mixture was washed with distilled water and extracted with EA. The organic layer was then dried with MgSO₄, the solvent was removed using a rotary evaporator, and the remaining substance was then purified with column chromatography to obtain compound H-20 (1.5 g, 47%).

Example 9: Preparation of compound H-21

After introducing compound 6-1 (3.0 g, 0.005 mol) of Example 6 in a flask, and adding compound 2-1 (2.2 g, 0.006 mol), Pd(PPh₃)₄ (346 mg, 0.0003 mol), K₂CO₃ (2 M, 10 mL), EtOH 10 mL, and toluene 20 mL, the reaction mixture was heated to 120°C and stirred for 8 hours. After the reaction, the mixture was washed with distilled water and extracted with EA. The organic layer was then dried with MgSO₄, the solvent was removed using a rotary evaporator, and the remaining substance was then purified with column chromatography to obtain compound H-21 (2.2 g, 65%).

Example 10: Preparation of compound D-8

After mixing 1,6-dibromopyrene (5 g, 13.8 mmol), diphenylamine (5.8 g, 34.2 mmol), Pd(OAc)₂(0.16 g, 0.71 mmol), and NaOtBu (6.7 g, 69.7 mmol), the mixture was introduced into a vacuum state and nitrogen atmosphere. P(t-Bu)₃ (1 mL, 2.0 mmol) and toluene 80 mL were then added to the reaction mixture, and stirred under reflux at 120°C for 5 hours. After the reaction, the mixture was extracted using EA and distilled water, and recrystallized with EA/MeOH to obtain compound D-8 (2.5 g, 9.3 mmol, 30%).

Example 11: Preparation of compound D-9

Compound D-9 (4 g, 50%) was obtained in the same manner as the synthetic method of compound D-8 by using 1,6-dibromopyrene and 4-(phenylamino)benzonitrile.

Example 12: Preparation of compound D-10

Compound D-10 (5.6 g, 40%) was obtained in the same manner as the synthetic method of compound D-8 by using 6-bromo-N,N-diphenylpyrene-1-amine and N-phenyl-4-(triphenylsilyl)aniline.

Example 13: Preparation of compound D-21

After mixing 1,6-dibromopyrene (13 g, 0.068 mol), 4-(phenylamino)benzonitrile (52 g, 0.144 mol), Cu (7.6 g, 0.12 mol), Cs₂CO₃ (54 g, 0.167 mol), and 18-Crown-6 (2.1 g, 0.008 mol) in a flask, the mixture was dissolved in 1,2-dichlorobenzene 300 mL and stirred under reflux at 190°C for 12 hours. After the reaction, 1,2-dichlorobenzene was removed using a distiller, an organic layer was extracted with EA, the remaining moisture was removed using magnesium sulfate, and the remaining substance was then separated with column chromatography to obtain compound 6-1 (15.5 g, 50%).

After mixing the obtained compound 6-1 (6 g, 0.012 mol), 3-(9H-carbazol-9-yl)phenyl boronic acid (5.4 g, 0.019 mol), Pd(PPh₃)₄ (732 mg, 0.63 mmol), and K₂CO₃ (5.2 g, 0.036 mol) in a flask, the mixture was dissolved by adding toluene 40 mL, EtOH 20 mL, and H₂O 20 mL, and then stirred at 120°C for 7 hours. After completing the reaction by adding H₂O slowly, an organic layer was extracted with EA, the remaining moisture was removed using magnesium sulfate, and the remaining substance was then dried and separated with column chromatography to obtain compound D-21 (4 g, 50%).

Example 14: Preparation of compound D-25

Compound D-25 (1.9 g, 30%) was obtained in the same manner as the synthetic method of compound D-25 by using compound 6-1 and 9-phenyl-9H-carbazol-3-yl boronic acid.

Example 15: Preparation of compound D-32

After dissolving 1.6-dibromopyrene (10 g, 27.8 mmol), indoline (6.9 mL, 61.1 mmol), palladium acetate (318 mg, 1.4 mmol), tri-t-butylphosphine (0.7 mL, 2.8 mmol), and cesium carbonate (27 g, 83.3 mmol) in toluene, the mixture was stirred under reflux for 24 hours at 120°C. After the reaction, the mixture was extracted with EA, washed with distilled water, dried with magnesium sulfate, and distilled under reduced pressure. The remaining substance was then separated with column chromatography to obtain compound D-32 (5 g, 41%).

Example 16: Preparation of compound D-88

Preparation of compound 16-1

After adding 3-aminobenzonitrile (50 g, 423 mmol), iodobenzene (39 mL, 352 mmol), palladium(II) acetate (Pd(OAc)₂) 3.9 g, tri-t-butylphosphine (P(t-Bu)₃) 8.5 mL, and Cs₂CO₃ 228 g to toluene, the mixture was stirred at 120°C for 24 hours. After the reaction, the mixture was slowly cooled to room temperature, H₂O was added thereto, and the mixture was extracted with EA. The organic layer was dried with Na₂SO₄, condensed, and separated with column chromatography to obtain compound 16-1 (70 g, 85%).

Preparation of compound 16-2

After adding compound 16-1 (8 g, 41 mmol), 1,6-dibromopyrene (30 g, 83 mmol), Cu 4.8 g, and Cs₂CO₃ 34 g to 1,2-dichlorobenzene 400 mL, the mixture was stirred at 200°C for 19 hours. After stirring, H₂O was slowly added to the mixture to complete the reaction, and the mixture was cooled to room temperature, H₂O was added thereto, and the mixture was extracted with EA. The organic layer was dried with Na₂SO₄, condensed, and separated with column chromatography to obtain compound 16-2 (12 g, 60%).

Preparation of compound D-88

After mixing compound 16-2 (5 g, 10 mmol) and 1,2,3,4-tetrahydroquinoline 1.6 mL, compound D-88 (3.8 g, 69%) was obtained by the synthetic method of compound 16-1.

Example 17: Preparation of compound D-149

Preparation of compound 17-1

After adding 4-isobutyrylbenzonitrile (6.2 g, 35.7 mmol) and phenylhydrazine (3.8 g, 35.7 mmol) to acetic acid 120 mL, the mixture was stirred at 80°C for 3 hours. After cooling the mixture, 1,2-dichloroethane 120 mL was added thereto, and sodium triacetoxyborohydride (NaBH(OAc)₃) (9.8 g, 46.6 mmol) was slowly added thereto. Thereafter, the mixture was stirred at room temperature for 30 minutes, H₂O was added thereto, and extracted with EA. The organic layer was dried with Na₂SO₄, condensed, and separated with column chromatography to obtain compound 17-1 (5.3 g, 60%).

Preparation of compound D-149

After mixing compound 16-2 (5 g, 10 mmol) and compound 17-1 (2.5 g, 20 mmol), compound D-149 (4.5 g, 70%) was obtained by the synthetic method of compound 16-1.

Example 18: Preparation of compound D-98

Preparation of compound 18-1

After dissolving 2,4-dibromo-6-fluoroaniline (25 g, 92.9 mmol), phenyl boronic acid (34 g, 278 mmol), tetrakis(triphenylphosphine)palladium (Pd(PPh₃)₄) (10 g, 9.29 mmol), and K₂CO₃ (64 g, 464 mmol) in a mixture solvent of toluene 300 mL, ethanol (EtOH) 100 mL, and H₂O 100 mL, the mixture was stirred at 120°C for 7 hours. After the reaction, H₂O was slowly added to the mixture to complete the reaction, and the mixture was extracted with EA. The organic layer was dried with Na₂SO₄ and separated with column chromatography to obtain compound 18-1 (20 g).

Preparation of compound 18-2

Compound 18-2 (23 g, 72%) was obtained in the same manner as the synthetic method of compound 16-1 by using compound 18-1 (30 g, 113.9 mmol) and iodobenzene (19.3 g, 94 mmol).

Preparation of compound 18-3

Compound 18-3 (2.2 g, 12%) was obtained in the same manner as the synthetic method of compound 16-2 by using compound 18-2 (10 g, 29.4 mmol) and 1,6-dibromopyrene (21 g, 58 mmol).

Preparation of compound D-98

Compound D-98 (1 g, 43%) was obtained in the same manner as the synthetic method of compound D-88 by using compound 18-3 (5 g, 8 mmol) and indoline (1 mL, 9.6 mmol).

Example 19: Preparation of compound D-153

Compound D-153 (1 g, 40%) was obtained in the same manner as the synthetic method of compound D-88 by using compound 19-3 (5 g, 8 mmol) and 1,2,3,4-tetrahydroquinoline-6-carbonitrile (1.5 g, 9.6 mmol).

Example 20: Preparation of compound D-147

Preparation of compound 20-1

Compound 20-1 (4 g, 60%) was obtained in the same manner as the synthetic method of compound 16-2 by using compound A (3 g, 8.6 mmol) and 1,6-dibromopyrene (6.2 g, 17.2 mmol).

Preparation of compound D-147

Compound D-147 (2.2 g, 50%) was obtained in the same manner as the synthetic method of compound 16-1 by using compound 20-1 (4 g, 6.4 mmol) and 1,2,3,4-tetrahydroquinoline-6-carbonitrile (1.2 g, 7.7 mmol).

Example 21: Preparation of compound D-148

Compound D-148 (2 g, 50%) was obtained in the same manner as the synthetic method of compound 16-1 by using compound 21-2 (6 g, 12.6 mmol) and 2-phenyl-1H-indole (3 g, 15.2 mmol).

Example 22: Preparation of compound D-150

Preparation of compound 22-1

Compound 22-1 (12 g, 52%) was obtained in the same manner as the synthetic method of compound 17-1 by using 2-methyl-1-phenylpropan-1-one (15.7 mL, 104 mmol) and phenylhydrazine (15 g, 104 mmol).

Preparation of compound 22-2

Compound 22-2 (10.6 g, 50%) was obtained in the same manner as the synthetic method of compound 16-2 by using diphenylamine (8 g, 47.3 mmol) and 1,6-dibromopyrene (34 g, 94.6 mmol).

Preparation of compound D-150

Compound D-150 (12 g, 52%) was obtained in the same manner as the synthetic method of compound 16-1 by using compound 22-1 (3.1 g, 13.9 mmol) and compound 22-2 (7.5 g, 16.7 mmol).

Example 23: Preparation of compound D-144

Compound D-144 (1.5 g, 20%) was obtained in the same manner as the synthetic method of compound 16-1 by using compound 22-1 (3.1 g, 13.9 mmol) and compound 16-2 (6 g, 12.7 mmol).

Example 24: Preparation of compound D-143

Preparation of compound 24-1

Compound 24-1 (7.5 g, 30%) was obtained in the same manner as the synthetic method of compound 17-1 by using 2-methyl-1-phenylpropan-1-one (15 g, 101 mmol) and p-cyanophenylhydrazine (17.1 g, 101 mmol).

Preparation of compound D-143

Compound D-143 (1.25 g, 20%) was obtained in the same manner as the synthetic method of compound 16-1 by using compound 24-1 (2.5 g, 10.1 mmol) and compound 16-2 (5 g, 10.6 mmol).

Example 25: Preparation of compound D-164

Compound D-164 (5.4 g, 78%) was obtained in the same manner as the synthetic method of compound 16-1 by using compound 16-2 (6.3 g, 13.3 mmol) and 1,2,3,4-tetrahydroquinoline-6-carbonitrile (2 g, 12.6 mmol).

Host compounds H-1 to H-62, and dopant compounds D-1 to D-184 used in an organic EL device were produced by the same synthetic methods as in Examples 1 to 25. Yield (%), MS/EIMS, UV (nm), and PL (nm) of the produced dopant compounds are shown in Table 1 as follows:

[Table 1]

Device Example 1: Production of an OLED device using the

organic electroluminescent compound according to the present invention

An OLED device was produced using the light-emitting materials according to the present invention. A transparent electrode indium tin oxide (ITO) thin film (15 Ω/sq) on a glass substrate for an organic light-emitting diode (OLED) device (Samsung Corning, Republic of Korea) was subjected to an ultrasonic washing with trichloroethylene, acetone, ethanol and distilled water, sequentially, and then was stored in isopropanol. Then, the ITO substrate was mounted on a substrate holder of a vacuum vapor depositing apparatus. N¹,N^1'-([1,1'-biphenyl]-4,4'-diyl)bis(N¹-(naphthalen-1-yl)-N⁴,N⁴-diphenylbenzen-1,4-diamine) was introduced into a cell of said vacuum vapor depositing apparatus, and then the pressure in the chamber of said apparatus was controlled to 10^-6 torr. Thereafter, an electric current was applied to the cell to evaporate the above introduced material, thereby forming a hole injection layer having a thickness of 60 nm on the ITO substrate. Then, N,N'-bis(α-naphthyl)-N,N'-diphenyl-4,4'-diamine was introduced into another cell of said vacuum vapor depositing apparatus, and was evaporated by applying an electric current to the cell, thereby forming a hole transport layer having a thickness of 20 nm on the hole injection layer. Thereafter, compound H-26 was introduced into one cell of the vacuum vapor depositing apparatus, as a host material, and compound D-9 was introduced into another cell as a dopant. The two materials were evaporated at different rates and were deposited in a doping amount of 3 wt% based on the total amount of the dopant and host to form a light-emitting layer having a thickness of 30 nm on the hole transport layer. Then, 2-(4-(9,10-di(naphthalen-2-yl)anthracen-2-yl)phenyl)-1-phenyl-1H-benzo[d]imidazole was introduced into one cell and lithium quinolate was introduced into another cell. The two materials were evaporated at the same rate and were deposited in a doping amount of 50 wt% each to form an electron transport layer having a thickness of 30 nm on the light-emitting layer. Then, after depositing lithium quinolate as an electron injection layer having a thickness of 2 nm on the electron transport layer, an Al cathode having a thickness of 150 nm was deposited by another vacuum vapor deposition apparatus on the electron injection layer. Thus, an OLED device was produced. All the materials used for producing the OLED device were purified by vacuum sublimation at 10^-6 torr prior to use.

The produced OLED device showed a blue emission having a luminance of 2020 cd/m² and a current density of 72.2 mA/cm². The half-life period was 169 hours.

Device Example 2: Production of an OLED device using the

organic electroluminescent compound according to the present invention

An OLED device was produced in the same manner as in Device Example 1, except for using compound H-1 as a host, and compound D-9 as a dopant of the light-emitting material.

The produced OLED device showed a blue emission having a luminance of 2020 cd/m² and a current density of 73.9 mA/cm². The half-life period was 162 hours.

Device Example 3: Production of an OLED device using the

organic electroluminescent compound according to the present invention

An OLED device was produced in the same manner as in Device Example 1, except for using compound H-45 as a host, and compound D-9 as a dopant of the light-emitting material.

The produced OLED device showed a blue emission having a luminance of 2020 cd/m²and a current density of 76.2 mA/cm². The half-life period was 165 hours.

Device Example 4: Production of an OLED device using the

organic electroluminescent compound according to the present invention

An OLED device was produced in the same manner as in Device Example 1, except for using compound H-49 as a host, and compound D-9 as a dopant of the light-emitting material.

The produced OLED device showed a blue emission having a luminance of 2140 cd/m² and a current density of 77.2 mA/cm². The half-life period was 164 hours.

Device Example 5: Production of an OLED device using the

organic electroluminescent compound according to the present invention

An OLED device was produced in the same manner as in Device Example 1, except for using compound H-48 as a host, and compound D-9 as a dopant of the light-emitting material.

The produced OLED device showed a blue emission having a luminance of 1890 cd/m²and a current density of 73.6 mA/cm². The half-life period was 170 hours.

Device Example 6: Production of an OLED device using the

organic electroluminescent compound according to the present invention

An OLED device was produced in the same manner as in Device Example 1, except for using compound H-20 as a host, and compound D-9 as a dopant of the light-emitting material.

The produced OLED device showed a blue emission having a luminance of 1890 cd/m² and a current density of 72.1 mA/cm². The half-life period was 178 hours.

Comparative Example 1: Production of an OLED device using conventional organic electroluminescent materials

An OLED device was produced in the same manner as in Device Example 1, except for using compound R-1 as a host, and compound D-9 as a dopant of the light-emitting material.

The produced OLED device showed a blue emission having a luminance of 1890 cd/m² and a current density of 67.6 mA/cm². The half-life period was 146 hours.

As shown above, it is verified that the organic electroluminescent device using the host and dopant combination according to the present invention has advanced lifespan characteristics while maintaining excellent current characteristics.

Claims

A combination of one or more host compounds represented by the following formula 1, and one or more dopant compounds represented by the following formula 2:

wherein

R₁ to R₁₈each independently represent hydrogen, deuterium, a halogen, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C3-C30)cycloalkyl, a substituted or unsubstituted (C1-C30)alkoxy, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, -SiR₃₁R₃₂R₃₃, a cyano or a hydroxyl; or R₁ to R₅, and R₁₄to R₁₈ are linked to an adjacent substituent(s) to form a mono- or polycyclic, substituted or unsubstituted (3- to 30-membered) alicyclic or aromatic ring in which the carbon atom of the ring may form a spiro structure, and the carbon atom(s) of the ring may be replaced with at least one hetero atom selected from nitrogen, oxygen and sulfur;

R₃₁ to R₃₃ each independently represent hydrogen, deuterium, a halogen, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl;

Ar₁ and Ar₂ each independently represent hydrogen, deuterium, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl; or are linked to an adjacent substituent(s) to form a mono- or polycyclic, substituted or unsubstituted (3- to 30-membered) alicyclic or aromatic ring in which the carbon atom of the ring may form a spiro structure, and the carbon atom(s) of the ring may be replaced with at least one hetero atom selected from nitrogen, oxygen and sulfur; where Ar₁ and Ar₂ are not simultaneously hydrogen; and

the heteroaryl contains at least one hetero atom selected from B, N, O, S, P(=O), Si and P;

wherein

Ar₃ represents a substituted or unsubstituted pyrene;

L represents a single bond, a substituted or unsubstituted (C6-C30)arylene, or a substituted or unsubstituted (3- to 30-membered)heteroarylene;

Ar₄ and Ar₅each independently represent a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl; or Ar₄ and Ar₅are linked with the nitrogen atom to form a mono- or polycyclic, substituted or unsubstituted (3- to 30-membered) alicyclic or aromatic ring, whose carbon atom(s) may be replaced with at least one hetero atom selected from nitrogen, oxygen and sulfur; and

n represents an integer of 1 to 3; where n is 2 or more, each of
are same or different.
The combination according to claim 1, wherein in formulae 1 and 2, the substituents of the substituted alkyl, the substituted cycloalkyl, the substituted alkoxy, the substituted aryl, the substituted heteroaryl, the substituted pyrene, the substituted arylene, the substituted heteroarylene, the substituted mono- or polycyclic, alicyclic or aromatic ring in R₁ to R₁₈, R₃₁ to R₃₃, Ar₁ to Ar₅, and L each independently are at least one selected from the group consisting of deuterium, a halogen, a (C1-C30)alkyl, a (C1-C30)alkyl substituted with a halogen, a (C1-C30)alkoxy, a (C6-C30)aryl, a (C6-C30)aryl substituted with a (3- to 30-membered)heteroaryl, a (C6-C30)aryl substituted with deuterium, a (3- to 30-membered)heteroaryl, a (3- to 30-membered)heteroaryl substituted with a (C6-C30)aryl, a (3- to 30-membered)heteroaryl substituted with a (C1-C30)alkyl(C6-C30)aryl, a (C3-C30)cycloalkyl, a (5- to 7-membered)heterocycloalkyl, a tri(C1-C30)alkylsilyl, a tri(C6-C30)arylsilyl, a di(C1-C30)alkyl(C6-C30)arylsilyl, a (C1-C30)alkyldi(C6-C30)arylsilyl, a (C2-C30)alkenyl, a (C2-C30)alkynyl, a cyano, a mono- or di- (C1-C30)alkylamino, a mono- or di- (C6-C30)arylamino, a (C1-C30)alkyl(C6-C30)arylamino, a di(C6-C30)arylboronyl, a di(C1-C30)alkylboronyl, a (C1-C30)alkyl(C6-C30)arylboronyl, a (C6-C30)aryl(C1-C30)alkyl, a (C1-C30)alkyl(C6-C30)aryl, a carboxyl, a nitro, and a hydroxyl.
The combination according to claim 1, wherein in formula 1, R₁ to R₁₈ each independently represent hydrogen, deuterium, a halogen, a substituted or unsubstituted (C1-C10)alkyl, a substituted or unsubstituted (C6-C20)aryl, or a substituted or unsubstituted (5- to 20-membered)heteroaryl; or R₁to R₅are linked to an adjacent substituent(s) to form a mono- or polycyclic, substituted or unsubstituted (5- to 20-membered) alicyclic or aromatic ring which may form a spiro structure; and

Ar₁ and Ar₂ each independently represent a substituted or unsubstituted (C6-C20)aryl, or a substituted or unsubstituted (5- to 20-membered)heteroaryl.
The combination according to claim 1, wherein in formula 2, Ar₃ represents a pyrene unsubstituted or substituted with a (C1-C6)alkyl, a (C6-C15)aryl, a (C6-C15)aryl substituted with deuterium, a (5- to 15-membered)heteroaryl substituted with a (C6-C15)aryl, or a (5- to 15-membered)heteroaryl substituted with a (C1-C6)alkyl(C6-C15)aryl;

L represents a single bond, or a substituted or unsubstituted (C6-C20)arylene; and

Ar₄ and Ar₅ each independently represent a substituted or unsubstituted (C6-C20)aryl, or a substituted or unsubstituted (5- to 20-membered)heteroaryl; or Ar₄ and Ar₅ are linked with the nitrogen atom to form a mono- or polycyclic, substituted or unsubstituted (5- to 20-membered) alicyclic or aromatic ring.
The combination according to claim 1, wherein in formula 2, Ar₃ is selected from the following structures:

wherein A represents deuterium, a halogen, a (C1-C30)alkyl, a (C1-C30)alkyl substituted with a halogen, a (C1-C30)alkoxy, a (C6-C30)aryl, a (C6-C30)aryl substituted with a (3- to 30-membered)heteroaryl, a (C6-C30)aryl substituted with deuterium, a (3- to 30-membered)heteroaryl, a (3- to 30-membered)heteroaryl substituted with a (C6-C30)aryl, a (3- to 30-membered)heteroaryl substituted with a (C1-C30)alkyl(C6-C30)aryl, a (C3-C30)cycloalkyl, a (5- to 7-membered)heterocycloalkyl, a tri(C1-C30)alkylsilyl, a tri(C6-C30)arylsilyl, a di(C1-C30)alkyl(C6-C30)arylsilyl, a (C1-C30)alkyldi(C6-C30)arylsilyl, a (C2-C30)alkenyl, a (C2-C30)alkynyl, a cyano, a mono- or di- (C1-C30)alkylamino, a mono- or di- (C6-C30)arylamino, a (C1-C30)alkyl(C6-C30)arylamino, a di(C6-C30)arylboronyl, a di(C1-C30)alkylboronyl, a (C1-C30)alkyl(C6-C30)arylboronyl, a (C6-C30)aryl(C1-C30)alkyl, a (C1-C30)alkyl(C6-C30)aryl, a carboxyl, a nitro, or a hydroxyl; and

m represents an integer of 0 to 4.
The combination according to claim 1, wherein in formula 2, Ar₄ and Ar₅ are linked with the nitrogen atom to form a ring selected from the following structures:
The combination according to claim 1, wherein the compound represented by formula 1 is selected from the group consisting of:
The combination according to claim 1, wherein the compound represented by formula 2 is selected from the group consisting of:
The organic electroluminescent device comprising the combination according to claim 1.