WO2012050347A1

WO2012050347A1 - Novel compounds for organic electronic material and organic electroluminescent device using the same

Info

Publication number: WO2012050347A1
Application number: PCT/KR2011/007544
Authority: WO
Inventors: Hong Yoep Na; Seok Keun Yoon; Soo Yong Lee; Young Gil Kim; Hyo Jung Lee; Hee Choon Ahn; Su Hyun Lee; Soo-Jin Hwang; Hee Sook Kim; Doo-Hyeon Moon; Kyung Joo Lee; Bong Ok Kim
Original assignee: Rohm and Haas Electronic Materials Korea Ltd; Rohm and Haas Electronic Materials LLC
Current assignee: DuPont Specialty Materials Korea Ltd; DuPont Electronic Materials International LLC
Priority date: 2010-10-13
Filing date: 2011-10-11
Publication date: 2012-04-19
Anticipated expiration: 2013-04-13
Also published as: CN103249800A; KR20120038060A; JP2013546171A; TW201226398A

Abstract

Provided are novel compounds for an organic electronic material and an organic electroluminescent device using the same. Because the compound for an organic electronic material disclosed herein exhibits high electron transport efficiency and thus prevents crystallization upon manufacturing a device, and also facilitates the formation of a layer, thus improving current properties of the device. Thereby, OLED devices having improved power efficiency as well as reduced operating voltage can be manufactured.

Description

NOVEL COMPOUNDS FOR ORGANIC ELECTRONIC MATERIAL AND ORGANIC ELECTROLUMINESCENT DEVICE USING THE SAME

The present invention relates to novel compounds for an organic electronic material and an organic electroluminescent device including the same.

Among display devices, electroluminescence (EL) devices, which are self-emissive display devices, are advantageous in that they provide a wide viewing angle, superior contrast and a fast response rate. In 1987, Eastman Kodak first developed an organic EL device using a low-molecular-weight aromatic diamine and aluminum complex as a substance for forming an electroluminescent layer [Appl. Phys. Lett. 51, 913, 1987].

Organic EL devices emit light using luminescence (phosphorescence or fluorescence) upon inactivation of excitons which result from electron-hole pairs formed by injecting charges into an organic layer formed between an electron injection electrode (cathode) and a hole injection electrode (anode). Organic EL devices can emit polarized light at a luminance of 100 ~ 10,000 cd/㎡ with a voltage of about 10 V, and simply adopt a fluorescent material, thereby emitting light in the blue to red spectral range. Such a device may be formed on a flexible transparent substrate such as a plastic, and may also operate at a lower voltage, namely 10 V or less, compared to that of a plasma display panel or an inorganic EL display, and may consume comparatively less power and exhibit superior color.

The most important factor in determining the performance including the luminous efficiency, life, etc., of an organic EL device is the electroluminescent material, and some requirements of the electroluminescent material include a high fluorescent quantum yield in a solid phase, high mobility of electrons and holes, slow decomposition upon vacuum deposition, and formation of a uniform and stable thin film.

The organic electroluminescent materials are broadly classified into high-molecular-weight materials and low-molecular-weight materials, and the low-molecular-weight materials include a metal complex compound and a pure organic electroluminescent material without a metal in terms of molecular structure. Such an electroluminescent material is known to be a chelate complex such as a tris(8-quinolinolato)aluminum complex or the like, a coumarin derivative, a tetraphenylbutadiene derivative, a bisstyrylarylene derivative, an oxadiazole derivative, etc., which have been reported to be able to emit visible light ranging from blue to red.

In order to achieve a full-color OLED display, RGB three electroluminescent materials have to be used. The development of RGB electroluminescent materials having high efficiency and long life is important to improve the total properties of the organic EL device. The electroluminescent material includes a host material and a dopant material for purposes of functionality. Typically, a device that has very superior electroluminescent properties is known to have a structure in which a host is doped with a dopant to form an electroluminescent layer. Recently, the development of an organic EL device having high efficiency and long life is being urgently called for. Particularly, taking into consideration the electroluminescent properties required of medium to large OLED panels, the development of materials very superior to conventional electroluminescent materials is urgent, and hence, the development of a host material is regarded as very important. As such, a host material which functions as the solvent in a solid phase and plays a role in transferring energy should be of high purity and must have a molecular weight appropriate to enabling vacuum deposition. Also, the glass transition temperature and heat decomposition temperature should be high to ensure thermal stability, and high electrochemical stability is required to attain a long life, and the formation of an amorphous thin film should become simple, and the force of adhesion to materials of other adjacent layers must be good but interlayer migration should not occur.

In the case where an organic EL device is manufactured using a doping technique, the rate at which energy is transferred from a host molecule in an excited state to a dopant is not 100%, and the host material as well as the dopant may emit light. In particular, in the case of a red-emitting electroluminescent device, a host material emits light in a wavelength range that is more clearly visible than does a dopant, and thus color purity is deteriorated due to unclear light emission of the host material. In practice, EL life and durability should be improved.

At present, CBP is most widely known as a host material for a phosphorescent material. High-efficiency OLEDs using a hole blocking layer comprising BCP, BAlq, etc. are reported. High-performance OLEDs using BAlq derivatives as a host were reported by Pioneer (Japan) and others.

Although these conventional materials provide good electroluminescent properties, they are disadvantageous in that degradation may occur during the high-temperature vapor deposition process in a vacuum because of the low glass transition temperature and poor thermal stability. Because the power efficiency of an OLED is given by (π/voltage)×current efficiency, power efficiency is inversely proportional to the voltage, and should thus be high in order to reduce the power consumption of an OLED. Actually, OLEDs using phosphorescent materials provide much higher current efficiency (cd/A) than do those using fluorescent materials. However, when existing materials such as BAlq, CBP or the like are used as the host of the phosphorescent material, there is no significant advantage in power efficiency (lm/W) over the OLEDs using fluorescent materials because of the high operating voltage. Furthermore, the life of an OLED device is not satisfactory, and therefore the development of a more stable host material having higher performance is required.

Therefore, the present invention has been made keeping in mind the problems occurring in the related art and an object of the present invention is to provide a compound for an organic electronic material, which has a backbone so that it can achieve better luminous efficiency and device life with appropriate color coordinates compared to conventional materials.

Another object of the present invention is to provide an organic electroluminescent device having high efficiency and a long life using the compound for an organic electronic material as an electroluminescent material.

Provided are a compound for an organic electronic material represented by Chemical Formula 1 below, and an organic electroluminescent device including the same. With superior luminous efficiency and excellent life, the compound for an organic electronic material according to the present invention may be used to manufacture an OLED device having very superior operating life and consuming less power due to improved power efficiency.

[Chemical Formula 1]

In Chemical Formula 1, L₁ and L₂ independently represent a single bond, (C6-C30)arylene or (C3-C30)heteroarylene;

X₁ and X₂ independently represent CR₄ or N, in which both X₁ and X₂ are not CR₄;

ring A represents a monocyclic or polycyclic (C6-C30)aromatic ring;

R₁ through R₄ independently represent hydrogen, deuterium, (C1-C30)alkyl, halo(C1-C30)alkyl, halogen, cyano, (C3-C30)cycloalkyl, 5- to 7-membered heterocycloalkyl, (C2-C30)alkenyl, (C2-C30)alkynyl, (C6-C30)aryl, (C1-C30)alkoxy, (C6-C30)aryloxy, (C3-C30)heteroaryl, (C6-C30)ar(C1-C30)alkyl, (C6-C30)arylthio, mono or di(C1-C30)alkylamino, mono or di(C6-C30)arylamino, tri(C1-C30)alkylsilyl, di(C1-C30)alkyl(C6-C30)arylsilyl, tri(C6-C30)arylsilyl, nitro or hydroxyl;

the arylene and heteroarylene of L₁ and L₂, the aromatic ring of ring A, and the alkyl, cycloalkyl, heterocycloalkyl, alkenyl, alkynyl, aryl and heteroaryl of R₁ through R₄ may be independently further substituted with one or more selected from the group consisting of deuterium, (C1-C30)alkyl, halo(C1-C30)alkyl, halogen, cyano, (C3-C30)cycloalkyl, 5- to 7-membered heterocycloalkyl, (C2-C30)alkenyl, (C2-C30)alkynyl, (C6-C30)aryl, (C1-C30)alkoxy, (C6-C30)aryloxy, (C3-C30)heteroaryl, (C1-C30)alkyl-substituted (C3-C30)heteroaryl, (C6-C30)aryl-substituted (C3-C30)heteroaryl, (C6-C30)ar(C1-C30)alkyl, (C6-C30)arylthio, mono or di(C1-C30)alkylamino, mono or di(C6-C30)arylamino, tri(C1-C30)alkylsilyl, di(C1-C30)alkyl(C6-C30)arylsilyl, (C1-C30)alkyldi(C6-C30)arylsilyl, tri(C6-C30)arylsilyl, nitro and hydroxyl;

the heteroarylene, heterocycloalkyl and heteroaryl include one or more heteroatoms selected from the group consisting of B, N, O, S, P(=O), Si and P; and

except for the case where

is hydrogen.

As described herein, "alkyl", "alkoxy" and other substituents containing the "alkyl" moiety include both linear and branched species, and the cycloalkyl includes polycyclic hydrocarbon ring such as adamantyl with or without substituent(s) or (C7-C30)bicycloalkyl with or without substituent(s) as well as a monocyclic hydrocarbon ring. As described herein, the term "aryl" means an organic radical derived from an aromatic hydrocarbon by the removal of one hydrogen atom, and includes a 4- to 7-membered, particularly 5- or 6-membered, single ring or fused ring, and even further includes a structure where a plurality of aryls are linked by single bonds. Specific examples thereof include phenyl, naphthyl, biphenyl, anthryl, indenyl, fluorenyl, phenanthryl, triphenylenyl, pyrenyl, perylenyl, chrysenyl, naphthacenyl, fluoranthenyl, or the like, but are not limited thereto. The naphthyl includes 1-naphthyl and 2-naphthyl, and the anthryl includes 1-anthryl, 2-anthryl and 9-anthryl, and the fluorenyl includes 1-fluorenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl and 9-fluorenyl. The "heteroaryl" described herein means an aryl group containing 1 to 4 heteroatom(s) selected from the group consisting of B, N, O, S, P(=O), Si and P as aromatic ring backbone atom(s) and the remaining aromatic ring backbone atom is carbon. It may be a 5- or 6-membered monocyclic heteroaryl, or polycyclic heteroaryl fused with one or more benzene rings, and may be partially saturated. In the present invention, "heteroaryl" includes a structure where one or more heteroaryls are linked by single bonds. The heteroaryl includes a divalent heteroaryl group wherein the heteroatom(s) in the ring may be oxidized or quaternized to form, for example, N-oxide or a quaternary salt. Specific examples thereof include monocyclic heteroaryl such as furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl, triazolyl, tetrazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, or the like, polycyclic heteroaryl such as benzofuranyl, benzothiophenyl, isobenzofuranyl, benzoimidazolyl, benzothiazolyl, benzoisothiazolyl, benzoisoxazolyl, benzoxazolyl, isoindolyl, indolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, carbazolyl, phenanthridinyl, benzodioxolyl, or the like, N-oxide thereof (e.g., pyridyl N-oxide, quinolyl N-oxide), quaternary salt thereof, and the like, but are not limited thereto.

As described herein, the term "(C1-C30)alkyl" includes (C1-C20)alkyl or (C1-C10)alkyl, and the term "(C6-C30)aryl" includes (C6-C20)aryl or (C6-C12)aryl. The term "(C3-C30)heteroaryl" includes (C3-C20)heteroaryl or (C3-C12)heteroaryl, and the term "(C3-C30)cycloalkyl" includes (C3-C20)cycloalkyl or (C3-C7)cycloalkyl. The term, "(C2-C30)alkenyl or alkynyl" includes (C2-C20)alkenyl or alkynyl, or (C2-C10)alkenyl or alkynyl.

To be specific, L₁ and L₂ independently represent a single bond, (C6-C30)arylene or (C3-C30)heteroarylene; X₁ and X₂ independently represent CR₄ or N, wherein both X₁ and X₂ are not CR₄; ring A represents a monocyclic or polycyclic (C6-C30)aromatic ring; R₁ through R₄ independently represent hydrogen, deuterium, (C6-C30)aryl or (C3-C30)heteroaryl; the arylene and heteroarylene of L₁ and L₂, the aromatic ring of ring A, and the aryl and heteroaryl of R₁ through R₄ may be independently further substituted with one or more selected from the group consisting of deuterium, (C1-C30)alkyl, halo(C1-C30)alkyl, (C6-C30)aryl, (C3-C30)heteroaryl, (C1-C30)alkyl-substituted (C3-C30)heteroaryl, (C6-C30)aryl-substituted (C3-C30)heteroaryl, and (C6-C30)ar(C1-C30)alkyl.

More specifically,

is

,

or

;

R_a and R_b independently represent (C1-C7)alkyl or (C6-C12)aryl;

R_c through R_e independently represent hydrogen, deuterium, (C1-C30)alkyl, halo(C1-C30)alkyl, (C6-C30)aryl, (C3-C30)heteroaryl, (C1-C30)alkyl-substituted (C3-C30)heteroaryl, (C6-C30)aryl-substituted (C3-C30)heteroaryl, and (C6-C30)ar(C1-C30)alkyl;

and

independently represent hydrogen or are selected from the following structures, except for the case where

is hydrogen.

More particularly, the compound for an organic electronic material according to the present invention may be exemplified by the following compounds, which are not intended to limit the present invention.

The compound for an organic electronic material according to the present invention may be prepared as shown in Scheme 1 below, but is not limited thereto, and may also be prepared using known methods of organic synthesis.

[Scheme 1]

In Scheme 1, X₁, X₂, L₁, L₂, ring A and R₁ through R₃ of Chemical Formula 1 are the same as defined in Chemical Formula 1; and X represents a halogen.

Provided is an organic electroluminescent device, which comprises a first electrode; a second electrode; and one or more organic layers interposed between the first electrode and the second electrode, wherein the organic layer comprises one or more compounds for an organic electronic material of Chemical Formula 1. The organic layer includes an electroluminescent layer, and the compound for an organic electronic material of Chemical Formula 1 is used as a host material in the electroluminescent layer.

In the electroluminescent layer, when the compound for an organic electronic material of Chemical Formula 1 is used as a host, one or more phosphorescent dopants may be included. The phosphorescent dopant applied to the organic electroluminescent device of the present invention is not specifically limited but may be selected from among compounds represented by Chemical Formula 2 below.

[Chemical Formula 2]

M¹L¹⁰¹L¹⁰²L¹⁰³

In Chemical Formula 2, M¹ is selected from the group consisting of Groups 7, 8, 9, 10, 11, 13, 14, 15 and 16 metals, and ligands L¹⁰¹, L¹⁰² and L¹⁰³ are independently selected from the following structures:

wherein R₂₀₁ through R₂₀₃ independently represent hydrogen, deuterium, halogen-substituted or unsubstituted (C1-C30)alkyl, (C1-C30)alkyl-substituted or unsubstituted (C6-C30)aryl or halogen;

R₂₀₄ through R₂₁₉ independently represent hydrogen, deuterium, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C1-C30)alkoxy, substituted or unsubstituted (C3-C30)cycloalkyl, substituted or unsubstituted (C2-C30)alkenyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted mono- or substituted or unsubstituted di-(C1-C30)alkylamino, substituted or unsubstituted mono- or substituted or unsubstituted di-(C6-C30)arylamino, SF₅, substituted or unsubstituted tri(C1-C30)alkylsilyl, substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl, substituted or unsubstituted tri(C6-C30)arylsilyl, cyano or halogen;

R₂₂₀ through R₂₂₃ independently represent hydrogen, deuterium, halogen-substituted or unsubstituted (C1-C30)alkyl, or (C1-C30)alkyl-substituted or unsubstituted (C6-C30)aryl;

R₂₂₄ and R₂₂₅ independently represent hydrogen, deuterium, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl or halogen, or R₂₂₄ and R₂₂₅ may be linked via (C3-C12)alkylene or (C3-C12)alkenylene with or without a fused ring to form an alicyclic ring and a monocyclic or polycyclic aromatic ring;

R₂₂₆ represents substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (C5-C30)heteroaryl, or halogen;

R₂₂₇ through R₂₂₉ independently represent hydrogen, deuterium, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, or halogen; and

Q represents

,

or

, wherein R₂₃₁ through R₂₄₂ independently represent hydrogen, deuterium, halogen-substituted or unsubstituted (C1-C30)alkyl, (C1-C30)alkoxy, halogen, substituted or unsubstituted (C6-C30)aryl, cyano or substituted or unsubstituted (C5-C30)cycloalkyl, or they may be linked to an adjacent substituent via alkylene or alkenylene to form a spiro ring or a fused ring, or may be linked to R₂₀₇ or R₂₀₈ via alkylene or alkenylene to form a saturated or unsaturated fused ring.

The phosphorescent dopant compound of Chemical Formula 2 may be exemplified by the following compounds, but is not limited thereto.

The organic electroluminescent device according to the present invention includes the compound for an organic electronic material of Chemical Formula 1, and may further include one or more compounds selected from the group consisting of arylamine compounds and styrylarylamine compounds. Specific examples of the arylamine compounds or the styrylarylamine compounds are illustrated in Korean Patent Publication No. 2010-0064712 or 2010-0048447, but are not limited thereto.

In the organic electroluminescent device according to the present invention, the organic layer may further comprise one or more metals selected from the group consisting of organic metals of Group 1, Group 2, 4^th period and 5^th period transition metals, lanthanide metals and d-transition elements or complex compounds, in addition to the compound for an organic electronic material of Chemical Formula 1. The organic layer may comprise an electroluminescent layer and a charge generating layer.

Further, the organic layer may include one or more organic electroluminescent layers including compounds emitting red, green and blue light at the same time, in addition to the above compound for an organic electronic material, in order to embody a white-emitting organic electroluminescent device. The compounds emitting red, green and blue light may be exemplified by the compounds described in Korean Patent Publication No. 2010-0064712 or 2010-0048447, but are not limited thereto.

In the organic electroluminescent device according to the present invention, a layer (hereinafter referred to as "surface layer" selected from a chalcogenide layer, a metal halide layer and a metal oxide layer may be placed on the inner surface of one or both electrodes among the pair of electrodes. Specifically, a metal chalcogenide (including the oxide) layer of silicon and aluminum may be placed on the anode surface of the electroluminescent medium layer, and a metal halide layer or a metal oxide layer may be placed on the cathode surface of the electroluminescent medium layer. Operation stability may be attained therefrom. The chalcogenide may be, for example, SiO_x (1 ≤ x ≤ 2), AlO_x (1 ≤ x ≤ 1.5), SiON, SiAlON, etc. The metal halide may be, for example, LiF, MgF₂, CaF₂, a rare earth metal fluoride, etc. The metal oxide may be, for example, Cs₂O, Li₂O, MgO, SrO, BaO, CaO, etc.

In the organic electroluminescent device according to the present invention, it is also preferable to arrange on at least one surface of the pair of electrodes thus manufactured a mixed region of an electron transport compound and a reductive dopant, or a mixed region of a hole transport compound and an oxidative dopant. In that case, because the electron transport compound is reduced to an anion, injection and transport of electrons from the mixed region to an electroluminescent medium are facilitated. In addition, because the hole transport compound is oxidized to a cation, injection and transport of holes from the mixed region to an electroluminescent medium are facilitated. Preferable oxidative dopants include a variety of Lewis acids and acceptor compounds. Preferable reductive dopants include alkali metals, alkali metal compounds, alkaline earth metals, rare-earth metals, and mixtures thereof. Further, a white-emitting organic electroluminescent device having two or more electroluminescent layers may be manufactured by employing a reductive dopant layer as a charge generating layer.

According to the present invention, compounds for an organic electronic material can be used to manufacture OLED devices having improved power efficiency as well as reduced operating voltage while exhibiting good luminous efficiency.

Hereinafter, the present invention is further described by taking representative compounds of the present invention as examples of the compounds for an organic electronic material according to the invention, a method of preparation thereof, and electroluminescent properties of the devices. But, those examples are provided only for the sake of illustrating the embodiments, and are not intended to limit the scope of the invention.

[Preparation Example 1] Preparation of Compound 1

Preparation of Compound 1-1

1-bromo-2-nitrobenzene 10g(49.5mmol) and 1-naphthalene boronic acid 10.2g(59.3mmol) were dissolved in a mixture comprising toluene 200mL, ethanol 50mL and water 50mL, and Pd(PPh₃)₄ 2.9g(2.5mmol) and potassium carbonate 20.5g(148.3mmol) were added. This mixture was stirred at 120℃ for 5 hours and cooled to room temperature, and the reaction was terminated with aqueous ammonium chloride 40mL. This mixture was extracted with EA 500mL, and the obtained organic layer was washed with distilled water 100mL. The organic layer was dried with anhydrous MgSO₄, and the organic solvent was removed under reduced pressure. Subsequently, the obtained solid was separated using silica gel column chromatography, yielding Compound 1-1 (10g, 81%).

Preparation of Compound 1-2

Compound 1-1 10g(40.1mmol) was dissolved in 1,2-dichlorobenzene 100mL, and triethoxyphosphine 100mL was added. This mixture was stirred at 150℃ for 20 hours and cooled to room temperature, and the solvents, namely, 1,2-dichlorobenzene and triethoxyphosphine were removed using distillation under reduced pressure. The remaining organic material was extracted with EA 300mL, and the obtained organic layer was washed with distilled water 40mL. The organic layer was dried with anhydrous MgSO₄, and the organic solvent was removed under reduced pressure. Subsequently, the obtained solid was separated using silica gel column chromatography, yielding Compound 1-2 (7g, 80%).

Preparation of Compound 1-3

Compound 1-2 7g(32.2mmol) was dissolved in DMF 150mL, and NBS 5.74g(32.2mmol) was added. This mixture was stirred at room temperature for 12 hours. Subsequently, the reaction was terminated with aqueous saturated sodium thiosulfate 30mL, and the mixture was extracted with EA 200mL, and the obtained organic layer was washed with distilled water 20mL. The organic layer was dried with anhydrous MgSO₄, and the organic solvent was removed under reduced pressure. The obtained solid was separated using silica gel column chromatography, yielding Compound 1-3 (9g, 94%).

Preparation of Compound 1-4

Compound 1-3 9g(30.4mmol) and iodobenzene 8.8mL(61mmol) were dissolved in toluene 150mL, and CuI 2.9g(15.2mmol), 1,2-diaminoethane 1mL(15.2mmol) and cesium carbonate 29.7g(91.2mmol) were added. This mixture was refluxed for 20 hours and cooled to room temperature, and the reaction was terminated with 10% aqueous hydrochloric acid. The mixture was extracted with EA 300mL, and the obtained organic layer was washed with distilled water 40mL. The organic layer was dried with anhydrous MgSO₄, and the organic solvent was removed under reduced pressure. The obtained solid was separated using silica gel column chromatography, yielding Compound 1-4 (8.5g, 75%).

Preparation of Compound 1-5

Compound 1-4 10g(26.9mmol) was dissolved in THF 120mL, and this solution was cooled to -78℃. n-BuLi(2.5M in hexane) 13mL was added at -78℃. This mixture was stirred at -78℃ for 1 hour, and a trimetoxyborane compound 4.5mL was added. The mixture was stirred for 2 hours, and the reaction was terminated with aqueous ammonium chloride 30mL. The mixture was extracted with EA 300mL, and the obtained organic layer was washed with distilled water 50mL. The organic layer was dried with anhydrous MgSO₄, and the organic solvent was removed under reduced pressure. The obtained solid was separated using recrystallization, yielding Compound 1-5 (6.7g, 74%).

Preparation of Compound 1-6

1,4-dibromobenzene 110g(466mmol) and 1-naphthalene boronic acid 40g(233mmol) were dissolved in a mixture comprising toluene 2L, ethanol 500mL and water 500mL, and Pd(PPh₃)₄ 13.4g(11.6mmol) and sodium carbonate 74g(698mmol) were added. This mixture was stirred at 120℃ 5 hours and cooled to room temperature, and the reaction was terminated with aqueous ammonium chloride 500mL. The mixture was extracted with EA 3L, and the obtained organic layer was washed with distilled water 1L. The organic layer was dried with anhydrous MgSO₄, and the organic solvent was removed under reduced pressure. Subsequently, the obtained solid was separated using silica gel filtration and recrystallization, yielding Compound 1-6 (50g, 50%).

Preparation of Compound 1-7

Compound 1-6 60g(0.21mol) was dissolved in THF 1L, and this solution was cooled to -78℃. n-BuLi(2.5M in hexane) 102mL was added at -78℃. This mixture was stirred at -78℃ for 1 hour and B(OMe)₃ 35.1mL was added. The mixture was stirred for 2 hours, and the reaction was terminated with aqueous ammonium chloride 300mL. The mixture was extracted with EA 2L, and the obtained organic layer was washed with distilled water 500mL. The organic layer was dried with anhydrous MgSO₄, and the organic solvent was removed under reduced pressure. Subsequently, the obtained solid was separated using recrystallization, yielding Compound 1-7 (34g, 65%).

Preparation of Compound 1-8

2,4-dichloroquinazoline 27.1g(136mmol) and Compound 1-7 33.8g(136mmol) were dissolved in a mixture comprising toluene 800mL, ethanol 200mL and water 200mL, and Pd(PPh₃)₄ 6.3g(5.45mmol) and sodium carbonate 43.3g(409mmol) were added. This mixture was stirred at 120℃ for 5 hours and cooled to room temperature, and the reaction was terminated with aqueous ammonium chloride 200mL. This mixture was extracted with EA 1.5L, and the obtained organic layer was washed with distilled water 500mL. The organic layer was dried with anhydrous MgSO₄, and the organic solvent was removed under reduced pressure. Subsequently, the obtained solid was separated using silica gel filtration and recrystallization, yielding Compound 1-8 (21g, 42%).

Preparation of Compound 1

Compound 1-8 5g(13.6mmol) and Compound 1-5 6.7g(19.9mmol) were dissolved in a mixture comprising toluene 100mL, ethanol 20mL, and water 20mL, and Pd(PPh₃)₄ 1.6g(1.4mmol) and potassium carbonate 5.7g(41.2mmol) were added. This mixture was stirred at 120℃ for 5 hours and cooled to room temperature, and the reaction was terminated with aqueous ammonium chloride 50mL. This mixture was extracted with EA 500mL, and the obtained organic layer was washed with distilled water 50mL. The organic layer was dried with anhydrous MgSO₄, and the organic solvent was removed under reduced pressure. Subsequently, the obtained solid was separated using silica gel filtration and recrystallization, yielding Compound 1 (8.2g, 96%).

MS/FAB: 623.74(exp.), 623.24(calculated)

[Preparation Example 2] Preparation of Compound 20

Preparation of Compound 2-1

Compound 2-1 (13g, 83%) was prepared by the same method as in the synthesis of Compound 1-1 in Preparation Example 1, with the exception that 9,9-dimethyl-9H-fluoren-2-yl boronic acid 17.7g(74.3mmol) was used in lieu of 1-naphthalene boronic acid.

Preparation of Compound 2-2

Compound 2-2 (4.2g, 36%) was prepared using Compound 2-1 13g(41.2mmol) by the same method as in the synthesis of Compound 1-2 in Preparation Example 1.

Preparation of Compound 2-3

Compound 2-2 6.8g(24mmol) and 1-bromo-4-iodobenzene 13.6g(48mmol) were dissolved in toluene 240mL, and Pd(OAc)₂ 270mg(1.2mmol), 50% P(i-Bu)₃ 1.6mL(2.4mmol) and NaOt-Bu 4.6g(48mmol) were added. This mixture was refluxed for two days and cooled to room temperature, and the reaction was terminated with aqueous saturated ammonium chloride 50mL. The mixture was extracted with EA 300mL, and the obtained organic layer was washed with distilled water 40mL. The organic layer was dried with anhydrous MgSO₄, and the organic solvent was removed under reduced pressure. Subsequently, the obtained solid was separated using silica gel column chromatography, yielding Compound 2-3 (4.3g, 41%).

Preparation of Compound 2-4

Compound 2-4 (2.5g, 63%) was prepared by the same method as in the synthesis of Compound 1-5 in Preparation Example 1, with the exception that Compound 2-3 4.3g(9.8mmol) was used in lieu of 1-naphthalene boronic acid.

Preparation of Compound 2-5

Compound 2-5 (16.5g, 37%) was prepared by the same method as in the synthesis of Compound 1-6 in Preparation Example 1, with the exception that 2,4-dichloroquinazoline 33g(139mmol) was used in lieu of 1,4-dibromobenzene and 9,9-dimethyl-9H-fluoren-2-yl boronic acid 25g(126mmol) was used in lieu of 1-naphthalene boronic acid.

Preparation of Compound 20

Compound 20 (1.7g, 60%) was prepared by the same method as in the synthesis of Compound 1 in Preparation Example 1, with the exception that Compound 2-5 1.5g(4.2 mmol) was used in lieu of Compound 1-8 and Compound 2-4 2g(5.0 mmol) was used in lieu of Compound 1-5.

MS/FAB: 679.85(exp.), 679.30(calculated)

[Preparation Example 3] Preparation of Compound 23

Compound 23 (1.8g, 62%) was prepared by the same method as in the synthesis of Compound 1 in Preparation Example 1, with the exception that Compound 2-4 2g(5.0 mmol) was used in lieu of Compound 1-5.

MS/FAB: 689.84(exp.), 689.28(calculated)

[Preparation Example 4] Preparation of Compound 25

Preparation of Compound 4-1

Compound 4-1 (94g, 60%) was prepared by the same method as in the synthesis of Compound 1-6 in Preparation Example 1, with the exception that 2-naphthalene boronic acid 157g(554mmol) was used in lieu of 1-naphthalene boronic acid and 1-bromo-4-iodobenzene 100g(581.7mmol) was used in lieu of 1,4-dibromobenzene.

Preparation of Compound 4-2

Compound 4-2 (57g, 67.0%) was prepared by the same method as in the synthesis of Compound 1-7 in Preparation Example 1, with the exception that Compound 4-1 94g(332mmol) was used in lieu of Compound 1-6.

Preparation of Compound 4-3

Compound 4-3 (51g, 99.9%) was prepared by the same method as in the synthesis of Compound 1-8 in Preparation Example 1, with the exception that Compound 4-2 57g(230mmol) was used in lieu of Compound 1-7.

Preparation of Compound 25

NaH 706mg(17.6mmol) was dissolved in DMF 200mL and Compound 2-2 dissolved in DMF 200mL was added. This mixture was stirred at room temperature for 1 hour, and slowly added to Compound 4-3 4.3g(11.8mmol) dissolved in DMF 170mL. This mixture was stirred at room temperature for one day. The mixture was quenched with MeOH 30mL and distilled water 30mL, filtered under reduced pressure and washed with distilled water and MeOH. The obtained solid was triturated with MeOH/EA, DMF and EA/THF, in that order, dissolved in chloroform, filtered with silica, and triturated with MeOH/EA, yielding Compound 25 (5.5g, 76.4%).

MS/FAB: 613.75(exp.), 613.25(calculated)

[Preparation Example 5] Preparation of Compound 26

Preparation of Compound 5-1

Compound 1-2 30g(0.138mol), 1,4-dibromobenzene 98g(3eq), CuI 13.1g(0.5eq), K₃PO₄ 90g(3eq), ethylenediamine 9.3mL(1eq) and toluene 700mL were stirred under reflux at 100℃ for 12 hours. After termination of the reaction, the mixture was extracted with EA, and column chromatography was performed, yielding white Compound 5-1 (39g, 56 %).

Preparation of Compound 5-2

Compound 5-1 39g, n-BuLi 50.3mL(1.2eq) and THF 500mL were stirred at -78℃ for 30 minutes. After completion of the stirring, B(OMe)₃ 36mL(1.5eq) was added, and the mixture was stirred for 12 hours and extracted with EA. Subsequently, column chromatography was conducted, yielding white Compound 5-2 (25g, 71%).

Preparation of Compound 26

Compound 2-5 6.8g(0.019mol), Compound 5-2 9.64g(1.5eq), 2M K₃PO₄ 12.4g(3eq), Pd(OAC)₂ 0.43g(0.1eq), P(t-Bu)₃ 3.8mL(0.3eq), toluene 120mL and EtOH 60mL were stirred for 12 hours. After the reaction, the mixture was extracted with EA, and column chromatography was conducted, yielding white Compound 26 (5.8g, 50%).

MS/FAB: 613.75(exp.), 613.25(calculated)

[Preparation Example 6] Preparation of Compound 9

Compound 1-3 6g(0.016mol), Compound 5-3 8.3g(1.5eq), 2M K₂CO₃ 6.8g(3eq), Pd(PPh₃)₄ 1.9g(0.1eq), toluene 100mL and EtOH 50mL were stirred at 100℃ for 12 hours. After the reaction, the mixture was extracted with EA, and column chromatography was conducted, yielding white Compound 9 (7g, 70%).

MS/FAB: 623.74(exp.), 623.24(calculated)

[Preparation Example 7] Preparation of Compound 21

Preparation of Compound 7-1

Compound 7-1 (11g, 44%) was prepared by the same method as in the synthesis of Compound 5-2 in Preparation Example 5, with the exception that 11,12-dihydro-12,12-dimethylindeno[2,1-a]carbazole 15.3g(53.99mmol) was used in lieu of Compound 1-2.

Preparation of Compound 7-2

Compound 7-2 (5.8g, 57%) was prepared by the same method as in the synthesis of Compound 5-3 in Preparation Example 5, with the exception that Compound 7-1 11g(0.025mmol) was used in lieu of Compound 5-1.

Preparation of Compound 21

Compound 21 (3.3g, 45%) was prepared by the same method as in the synthesis of Compound 26 in Preparation Example 5, with the exception that Compound 7-2 5.1g(12.77mmol) was used in lieu of Compound 5-2.

MS/FAB: 679.85(exp.), 679.30(calculated)

[Preparation Example 8] Preparation of Compound 13

Preparation of Compound 8-1

Compound 8-1 (18.4g, 45%) was prepared by the same method as in the synthesis of Compound 1-6 in Preparation Example 1, with the exception that 1,3-dibromobenzene 25g(0.14mol) was used in lieu of 1,4-dibromobenzene.

Preparation of Compound 8-2

Compound 8-2 (10g, 63%) was prepared by the same method as in the synthesis of Compound 1-7 in Preparation Example 1, with the exception that Compound 8-1 18.4g(0.065mol) was used in lieu of Compound 1-6.

Preparation of Compound 8-3

Compound 8-3 (4.5g, 37%) was prepared by the same method as in the synthesis of Compound 1-8 in Preparation Example 1, with the exception that Compound 8-2 8.8g(85.48mmol) was used in lieu of Compound 1-7.

Preparation of Compound 13

Compound 13 (4.3g, 56%) was prepared by the same method as in the synthesis of Compound 1 in Preparation Example 1, with the exception that Compound 8-3 4.5g(0.012mol) was used in lieu of Compound 1-8, and Compound 5-2 4.9g(0.014mol) was used in lieu of Compound 1-5.

MS/FAB: 623.74(exp.), 623.24(calculated)

[Preparation Example 9] Preparation of Compound 10

Preparation of Compound 9-1

3-bromo-9-phenyl-9H-carbazole 50g(0.155mol) was dissolved in THF, and n-buLi 75mL(0.186mol, 2.5M in hexane) was slowly added at -78℃. 1 hour later, triisopropylborate 53.5mL(0.233mol) was added. This mixture was stirred at room temperature for 12 hours and distilled water was added. The mixture was extracted with EA, dried with magnesium sulfate, distilled under reduced pressure, and recrystallized from MC and hexane, yielding Compound 9-1 (33g, 0.115mol, 74%).

Preparation of Compound 10

Compound 10 (5.7g, 9.94mmol, 73%) was prepared by the same method as in the synthesis of Compound 1 in Preparation Example 1, with the exception that Compound 9-1 5.87g(20.44mmol) was used in lieu of Compound 1-5.

MS/FAB: 573.68(exp.), 573.22(calculated)

[Preparation Example 10] Preparation of Compound 14

Compound 4-3 5g(13.63mmol), Compound 5-2 6.9g(20.45mmol), Pd(PPh₃)₄ 1.58g(1.36mmol), 2M K₂CO₃ 5.65g(40.9mmol), toluene 80mL, and ethanol 40mL were mixed and stirred at 120℃ for 5 hours. The mixture was cooled to room temperature, and distilled water was added. The mixture was extracted with EA, distilled under reduced pressure, and recrystallized from EA and MeOH. Further, recrystallization from THF and EA was conducted, yielding Compound 14 (2.7g, 4.43mmol, 32%).

MS/FAB: 623.74(exp.), 623.24(calculated)

[Preparation Example 11] Preparation of Compound 24

Compound 4-3 3.9g(10.7mmol), Compound 7-2 5.2g(12.9mmol) and sodium carbonate 3.4g(32.1mmol) were dissolved in a mixture comprising toluene 50mL, ethanol 20mL, and distilled water 20mL, and Pd(PPh₃)₄ 0.6g(0.6mmol) was added. This mixture was stirred at 120℃ for 5 hours, cooled to room temperature and extracted with EA 300mL, and the obtained organic layer was washed with distilled water 50mL. The organic layer was dried with anhydrous magnesium sulfate, and the organic solvent was removed under reduced pressure. The obtained solid was separated using silica gel column chromatography and recrystallization, yielding Compound 24 (2.3g, 31%).

MS/FAB: 689.84(exp.), 689.28(calculated)

[Example 1] Manufacture of OLED device using the compound for an organic electronic material according to the present invention

An OLED device was manufactured by using the electroluminescent material according to the present invention. First, a transparent electrode ITO thin film (15Ω/□) obtained from a glass for OLED (manufactured by Samsung Corning) was subjected to ultrasonic washing with trichloroethylene, acetone, ethanol and distilled water, sequentially, and stored in isopropanol before use. Then, the ITO substrate was equipped in a substrate holder of a vacuum vapor deposition apparatus, and 4,4'-4''-tris(N,N-(2-naphthyl)-phenylamino)triphenylamine (2-TNATA) was placed in a cell of the vacuum vapor deposition apparatus, which was then ventilated up to 10^-6 torr of vacuum in the chamber. Then, electric current was applied to the cell to evaporate 2-TNATA, 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 (NPB) was placed in another cell of the vacuum vapor deposition apparatus, and electric current was applied to the cell to evaporate NPB, thereby forming a hole transport layer having a thickness of 20 nm on the hole injection layer. After forming the hole injection layer and the hole transport layer, an electroluminescent layer was formed thereon as follows. Compound 1 according to the present invention as a host was placed in a cell, and Ir(piq)₃ [tris(1-phenylisoquinoline)iridium(III)] as a dopant was placed in another cell, within a vacuum vapor deposition apparatus. The two materials were evaporated at different rates such that 4 ~ 10 wt% doping taken place, and thereby the electroluminescent layer having a thickness of 30 nm was vapor-deposited on the hole transport layer. Subsequently, tris(8-hydroxyquinoline)-aluminum(III) (Alq) was vapor-deposited to a thickness of 20 nm as an electron transport layer on the electroluminescent layer. Subsequently, lithium quinolate (Liq) was vapor-deposited to a thickness of 1 ~ 2 nm as an electron injection layer, and an Al cathode having a thickness of 150 nm was vapor-deposited using another vacuum vapor deposition apparatus to manufacture an OLED device.

Each compound used in the OLED device as the electroluminescent material was purified by vacuum sublimation at 10^-6 torr before use.

As a result, the flow of current of 14.3 mA/cm² at a voltage of 6.8 V was confirmed and a red light of 1050 cd/m² was emitted.

[Example 2]

An OLED device was manufactured by the same method as Example 1 except that Compound 18 was used as a host material in the electroluminescent layer.

As a result, the flow of current of 15.1 mA/cm² at a voltage of 6.5 V was confirmed and a red light of 1040 cd/m² was emitted.

[Example 3]

An OLED device was manufactured by the same method as Example 1 except that Compound 9 was used as a host material in the electroluminescent layer.

As a result, the flow of current of 13.9 mA/cm² at a voltage of 6.5 V was confirmed and a red light of 1060 cd/m² was emitted.

[Example 4]

An OLED device was manufactured by the same method as Example 1 except that Compound 20 was used as a host material in the electroluminescent layer.

As a result, the flow of current of 14.5 mA/cm² at a voltage of 6.9 V was confirmed and a red light of 1030 cd/m² was emitted.

[Example 5]

An OLED device was manufactured by the same method as Example 1 except that Compound 25 was used as a host material in the electroluminescent layer.

As a result, the flow of current of 14.2 mA/cm² at a voltage of 7.0 V was confirmed and a red light of 1050 cd/m² was emitted.

[Comparative Example 1]

An OLED device was manufactured by the same method as Example 1 except that 4,4'-bis(carbazol-9-yl)biphenyl (CBP) was used as a host material in the electroluminescent layer in lieu of the compound according to the present invention, and bis(2-methyl-8-quinolinato)(p-phenylphenolate)aluminum(III) (BAlq) was used for a hole blocking layer.

As a result, the flow of current of 15.3 mA/cm² at a voltage of 7.5 V was confirmed and a red light of 1000 cd/m² was emitted.

It was confirmed that the organic electroluminescent compounds developed in the present invention showed superior electroluminescent properties compared to the conventional materials. Devices using the organic electroluminescent compounds according to the present invention as a host material can exhibit superior electroluminescent properties and can reduce operating voltage to thus increase power efficiency, and thereby consumes less power.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions, and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims

A compound for an organic electronic material, represented by Chemical Formula 1 below.

[Chemical Formula 1]

In Chemical Formula 1, L₁ and L₂ independently represent a single bond, (C6-C30)arylene or (C3-C30)heteroarylene;

X₁ and X₂ independently represent CR₄ or N, in which both X₁ and X₂ are not CR₄;

ring A represents a monocyclic or polycyclic (C6-C30)aromatic ring;

R₁ through R₄ independently represent hydrogen, deuterium, (C1-C30)alkyl, halo(C1-C30)alkyl, halogen, cyano, (C3-C30)cycloalkyl, 5- to 7-membered heterocycloalkyl, (C2-C30)alkenyl, (C2-C30)alkynyl, (C6-C30)aryl, (C1-C30)alkoxy, (C6-C30)aryloxy, (C3-C30)heteroaryl, (C6-C30)ar(C1-C30)alkyl, (C6-C30)arylthio, mono or di(C1-C30)alkylamino, mono or di(C6-C30)arylamino, tri(C1-C30)alkylsilyl, di(C1-C30)alkyl(C6-C30)arylsilyl, tri(C6-C30)arylsilyl, nitro or hydroxyl;

the arylene and heteroarylene of L₁ and L₂, the aromatic ring of ring A, and the alkyl, cycloalkyl, heterocycloalkyl, alkenyl, alkynyl, aryl and heteroaryl of R₁ through R₄ may be independently further substituted with one or more selected from the group consisting of deuterium, (C1-C30)alkyl, halo(C1-C30)alkyl, halogen, cyano, (C3-C30)cycloalkyl, 5- to 7-membered heterocycloalkyl, (C2-C30)alkenyl, (C2-C30)alkynyl, (C6-C30)aryl, (C1-C30)alkoxy, (C6-C30)aryloxy, (C3-C30)heteroaryl, (C1-C30)alkyl-substituted (C3-C30)heteroaryl, (C6-C30)aryl-substituted (C3-C30)heteroaryl, (C6-C30)ar(C1-C30)alkyl, (C6-C30)arylthio, mono or di(C1-C30)alkylamino, mono or di(C6-C30)arylamino, tri(C1-C30)alkylsilyl, di(C1-C30)alkyl(C6-C30)arylsilyl, (C1-C30)alkyldi(C6-C30)arylsilyl, tri(C6-C30)arylsilyl, nitro and hydroxyl;

the heteroarylene, heterocycloalkyl and heteroaryl include one or more heteroatoms selected from the group consisting of B, N, O, S, P(=O), Si and P; and

except for the case where
is hydrogen.
The compound for an organic electronic material of claim 1, wherein L₁ and L₂ independently represent a single bond, (C6-C30)arylene or (C3-C30)heteroarylene; X₁ and X₂ independently represent CR₄ or N, wherein both X₁ and X₂ are not CR₄; ring A represents a monocyclic or polycyclic (C6-C30)aromatic ring; R₁ through R₄ independently represent hydrogen, deuterium, (C6-C30)aryl or (C3-C30)heteroaryl; the arylene and heteroarylene of L₁ and L₂, the aromatic ring of ring A, and the aryl and heteroaryl of R₁ through R₄ may be independently further substituted with one or more selected from the group consisting of deuterium, (C1-C30)alkyl, halo(C1-C30)alkyl, (C6-C30)aryl, (C3-C30)heteroaryl, (C1-C30)alkyl-substituted (C3-C30)heteroaryl, (C6-C30)aryl-substituted (C3-C30)heteroaryl, and (C6-C30)ar(C1-C30)alkyl.
The compound for an organic electronic material of claim 2, wherein
is
,
or
;

R_a and R_b independently represent (C1-C7)alkyl or (C6-C12)aryl;

R_c through R_e independently represent hydrogen, deuterium, (C1-C30)alkyl, halo(C1-C30)alkyl, (C6-C30)aryl, (C3-C30)heteroaryl, (C1-C30)alkyl-substituted (C3-C30)heteroaryl, (C6-C30)aryl-substituted (C3-C30)heteroaryl, and (C6-C30)ar(C1-C30)alkyl;

and
independently represent hydrogen or are selected from the following structures, except for the case where
is hydrogen.
The compound for an organic electronic material of claim 3, which is selected from following compounds.
An organic electroluminescent device comprising the compound for an organic electronic material of any one of claims 1 to 4.
The organic electroluminescent device of claim 5, which comprises a first electrode; a second electrode; and one or more organic layers interposed between the first electrode and the second electrode, wherein the organic layer comprises one or more compounds for an organic electronic material and one or more phosphorescent dopants.
The organic electroluminescent device of claim 6, wherein the organic layer further comprises one or more amine compounds selected from the group consisting of arylamine compounds and styrylarylamine compounds.
The organic electroluminescent device of claim 6, wherein the organic layer further comprises one or more metals selected from the group consisting of organic metals of Group 1, Group 2, 4^th period and 5^th period transition metals, lanthanide metals and d-transition elements or complex compounds.
The organic electroluminescent device of claim 6, wherein the organic layer comprises an electroluminescent layer and a charge generating layer.
The organic electroluminescent device of claim 6, wherein the organic layer further comprises one or more organic electroluminescent layers emitting red, green and blue light to emit white light.