KR101996651B1 - Fluorene derivatives and organic light-emitting diode including the same - Google Patents

Abstract

The present invention relates to a fluorene derivative represented by the following formula (1) and an organic electroluminescent device including the same, wherein the organic electroluminescent device comprising the fluorene derivative according to the present invention has high thermal stability, low driving voltage, And longevity.
[Chemical Formula 1]

Description

[0001] The present invention relates to a fluorene derivative and an organic electroluminescent device including the same,

The present invention relates to a novel fluorene derivative that can be used as a light emitting layer material and an organic electroluminescent device including the same. More particularly, the present invention relates to a fluorene derivative having excellent thermal stability, low driving voltage, And an organic electroluminescent device including the same.

In recent years, organic light emitting devices capable of being driven by a low voltage in a self-emission type have superior viewing angles and contrast ratios as compared with liquid crystal displays (LCDs), which are the mainstream of flat panel display devices, and require no backlight, It is attracting attention as a next-generation display device because it is advantageous in terms of power and has a wide color reproduction range.

In organic light emitting diodes (OLEDs), when electrons are injected into an organic light emitting layer formed between an electron injection electrode (cathode) and a hole injection electrode (anode), electrons and holes are paired, to be.

An organic electroluminescent device using an organic light emitting phenomenon usually has a structure including an anode, an anode, and an organic material layer therebetween. Here, in order to increase the efficiency and stability of the organic electroluminescent device, the organic material layer may have a multi-layer structure composed of different materials and may include a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, . When a voltage is applied between the two electrodes in the structure of the organic electroluminescent device, holes are injected into the anode, electrons are injected into the organic layer, and excitons are formed when injected holes and electrons meet. When it falls back to the ground state, the light comes out.

The organic electroluminescent device can be formed on a flexible transparent substrate such as a plastic substrate and can be driven at a voltage as low as 10 V or less as compared with a plasma display panel or inorganic electroluminescence display The power consumption is relatively low, and the color is excellent. In addition, organic electroluminescent devices can display three colors of green, blue, and red, making them an object of interest for a large number of people as a next-generation rich color display device.

In order for the organic electroluminescent device to sufficiently exhibit the above-described excellent characteristics, materials constituting the organic material layer in the device, such as a hole injecting material, a hole transporting material, a light emitting material, an electron transporting material, and an electron injecting material are supported by a stable and efficient material However, the development of a stable and efficient organic material layer material for an organic electroluminescence device has not been sufficiently developed yet. Therefore, there is a continuing need in the art for the development of new materials having low-voltage driving, high efficiency and long life.

Accordingly, a first object of the present invention is to provide a fluorene derivative having excellent thermal stability, low driving voltage, and excellent luminescence properties such as luminance.

A second object of the present invention is to provide an organic electroluminescent device comprising the fluorene derivative.

In order to achieve the first object, the present invention provides a fluorene derivative represented by the following formula (1).

[Chemical Formula 1]

In the above formula (1)

X ₁ To X ₁₈ Each independently represent a substituted or unsubstituted L, a substituted or unsubstituted arylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 24 carbon atoms, a substituted or unsubstituted C2-C24 heteroaryl A substituted or unsubstituted alkyl group having 1 to 24 carbon atoms, a substituted or unsubstituted 1 to 24 heteroalkyl group, a substituted or unsubstituted cycloalkyl group having 3 to 24 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 24 carbon atoms A halogen atom, a substituted or unsubstituted aryloxy group having 6 to 24 carbon atoms, a substituted or unsubstituted silyl group, deuterium, and hydrogen,

R ₁ To R ₄ each independently represents a substituted or unsubstituted arylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 24 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 24 carbon atoms, A substituted or unsubstituted alkyl group having 1 to 24 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 24 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 24 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 24 carbon atoms, , A halogen group, a substituted or unsubstituted aryloxy group having 6 to 24 carbon atoms, a substituted or unsubstituted silyl group having 1 to 24 carbon atoms, deuterium and hydrogen,

A ₁ to A ₂ each independently represent a substituted or unsubstituted aryl group having 6 to 24 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 24 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 24 carbon atoms, A substituted or unsubstituted heteroalkyl group having from 3 to 24 carbon atoms, a substituted or unsubstituted cycloalkyl group having from 3 to 24 carbon atoms,

n is an integer of 1 to 4;

According to an embodiment of the present invention, the X ₁ To X ₁₈ , R ₁ To R < ₄ > and A &_lt; ₁ > to A &_lt; ₂ > may be bonded to each other to form a saturated or unsaturated ring or may be attached or fused by a pendant method.

According to one embodiment of the present invention, X ₁ to X ₁₈ , R ₁ To R ₄ And The substituents of A ₁ to A ₂ are a substituted or unsubstituted arylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 24 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 24 carbon atoms, A substituted or unsubstituted alkyl group having 1 to 24 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 24 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 24 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 24 carbon atoms, A halogen atom, a substituted or unsubstituted aryloxy group having 6 to 24 carbon atoms, a substituted or unsubstituted silyl group having 1 to 24 carbon atoms, deuterium, and hydrogen.

According to another aspect of the present invention,

And a light emitting layer interposed between the anode and the cathode, wherein the light emitting layer comprises a fluorene derivative represented by the formula (1).

Since the fluorene derivative represented by the formula (1) according to the present invention has excellent luminous efficiency as compared with the conventional materials, the organic electroluminescent device including the same has high thermal stability, low driving voltage, excellent luminance and long- And improve the luminous efficiency.

1 is a schematic view of an organic electroluminescent device according to one embodiment of the present invention.

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

The present invention improves thermal stability, brightness and lifetime characteristics compared to the conventional light emitting layer host material, and is characterized in that various substituents are bonded with the structure represented by the above formula (1).

In the fluorene derivative of the above formula (1) according to the present invention, the substituent will be described in more detail as follows.

Wherein X ₁ to X ₁₈ , R ₁ To R ₄ And The substituents of A ₁ to A ₂ are a substituted or unsubstituted arylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 24 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 24 carbon atoms, A substituted or unsubstituted alkyl group having 1 to 24 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 24 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 24 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 24 carbon atoms, A halogen atom, a substituted or unsubstituted aryloxy group having 6 to 24 carbon atoms, a substituted or unsubstituted silyl group having 1 to 24 carbon atoms, deuterium, and hydrogen.

Further, the X ₁ To X ₁₈ , R ₁ To R < ₄ > and A &_lt; ₁ > to A &_lt; ₂ > may be bonded to each other to form a saturated or unsaturated ring or may be attached or fused by a pendant method.

Specific examples of the alkyl group as the substituent used in the present invention include a methyl group, an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isoamyl group, a hexyl group, a heptyl group, A halogen atom, a hydroxyl group, a nitro group, a cyano group, a trifluoromethyl group, a silyl group (in this case, a " alkylsilyl group "hereinafter), a substituted or unsubstituted amino group _{(-NH 2, -NH (R)} , -N (R ') (R"), where R, R' and R "are independently C 1 each A hydrazine group, a hydrazone group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, an alkyl group having 1 to 24 carbon atoms, a halogenated alkyl group having 1 to 24 carbon atoms, an alkylamino group having 1 to 24 carbon atoms, An alkenyl group having 2 to 24 carbon atoms, an alkynyl group having 2 to 24 carbon atoms, An aryl group having from 5 to 24 carbon atoms, an aryl group having from 5 to 24 carbon atoms, an arylalkyl group having from 6 to 24 carbon atoms, a heteroaryl group having from 3 to 24 carbon atoms, or a heteroarylalkyl group having from 3 to 24 carbon atoms.

Specific examples of the alkoxy group used as the substituent in the compound of the present invention include methoxy, ethoxy, propoxy, isobutyloxy, sec-butyloxy, pentyloxy, isoamyloxy, And can be substituted with substituents similar to those in the case of the alkyl group.

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

Specific examples of the aryl group as the substituent group used in the compound of the present invention include a phenyl group, a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, a 4-ethylphenyl group, Examples of the aryl group include phenyl group, 4-methylbiphenyl group, 4-ethylbiphenyl group, o-terphenyl group, m-terphenyl group, p-terphenyl group, 1-naphthyl group, , Anthryl group, phenanthryl group, pyrenyl group, fluorenyl group, tetrahydronaphthyl group and the like, which may be substituted with the same substituents as those in the case of the alkyl group.

Specific examples of the heteroaryl group used as the substituent in the compound of the present invention include pyridinyl, pyrimidinyl, triazinyl, indolinyl, quinolinyl, pyrrolidinyl, piperidinyl, An oxazolyl group, an oxadiazolyl group, a benzoxazolyl group, a thiazolyl group, a thiadiazolyl group, a benzothiazolyl group, a triazolyl group, an imidazolyl group, a benzoimidazole group, And at least one of the hydrogen atoms of the heteroaryl group may be substituted with the same substituent as the alkyl group.

The aryloxy group used in the present invention means an -O-aryl radical, wherein the aryl group is as defined above, and specific examples include phenoxy, naphthoxy, anthracenyloxy, phenanthrenyloxy, fluorenyloxy, Indenyloxy and the like, and at least one hydrogen atom contained in the aryloxy group may be further substituted.

Specific examples of the silyl group used in the present invention include trimethylsilyl, triethylsilyl, triphenylsilyl, trimethoxysilyl, dimethoxyphenylsilyl, diphenylmethylsilyl, silyl, diphenylvinylsilyl, methylcyclobutylsilyl , Dimethyl furyl silyl and the like.

In the present invention, the term "substituted or unsubstituted" means an aryl group, a heteroaryl group, an alkyl group, a heteroalkyl group, a cycloalkyl group, an alkoxy group, a cyano group, a halogen group, an aryloxy group, an alkylsilyl group, , Germanium, phosphorus, boron, deuterium and hydrogen. The term " substituted or unsubstituted "

The fluorene derivative according to the above formula (1) having the above-mentioned structure is not limited by the following specific examples, but specifically, it is preferable that any of the compounds represented by the following formulas (2) to Can be one

[Chemical Formula 2] < EMI ID =

[Chemical Formula 5] < EMI ID =

[Chemical Formula 8]

[Chemical Formula 12] [Chemical Formula 13]

[Chemical Formula 14]

[Chemical Formula 18] [Chemical Formula 19]

[Chemical Formula 20]

[Chemical Formula 23] [Chemical Formula 25]

[Chemical Formula 26]

[Chemical Formula 30] [Chemical Formula 30]

[Chemical Formula 32]

[Chemical Formula 35]

[Chemical Formula 38] [Chemical Formula 39]

The present invention also relates to a fuel cell comprising an anode; Cathode; And a layer interposed between the anode and the cathode, the layer including a fluorene derivative represented by the formula (1).

In this case, the layer containing the fluorene derivative is preferably a light emitting layer between the anode and the cathode, and a hole injecting layer, a hole transporting layer, an electron blocking layer, a hole blocking layer, an electron transporting layer, ≪ RTI ID = 0.0 > and / or < / RTI >

As a specific example, a hole transport layer (HTL) may be additionally stacked, and an electron transport layer (ETL) may be further stacked between the cathode and the organic emission layer. An electron donor molecule having a low ionization potential is used as the material of the hole transport layer. A diamine, triamine or tetraamine derivative having a basic skeleton of triphenylamine is used as the material of the hole transport layer. It is widely used.

In the present invention, the material for the hole transport layer is not particularly limited as long as it is commonly used in the art. For example, N, N'-bis (3-methylphenyl) -N, N'- , 1-biphenyl] -4,4'-diamine (TPD) or N, N'-di (naphthalene-1-yl) -N, N'-diphenylbenzidine (a-NPD).

A HIL (Hole Injection Layer) may be additionally deposited on the lower portion of the hole transport layer. The material for the hole injection layer is not particularly limited as long as it is commonly used in the art. For example, (4,4 ', 4 "-tri (N-carbazolyl) triphenylamine), m-MTDATA (4,4', 4" -tris- (3-methylphenylphenylamino) triphenylamine).

In addition, the electron transport layer used in the organic electroluminescent device according to the present invention can transport electrons supplied from the cathode smoothly to the organic luminescent layer and inhibit the movement of holes which are not bonded in the organic luminescent layer, . The material of the electron transport layer is not particularly limited as long as it is commonly used in the art. For example, oxadiazole derivative PBD, BMD, BND or Alq ₃ can be used.

Meanwhile, an electron injection layer (EIL) may be further formed on the electron transport layer to facilitate injection of electrons from the cathode to ultimately improve power efficiency. The electron injection layer material As long as it is commonly used in the art, it can be used without any particular limitation. For example, materials such as LiF, NaCl, CsF, Li ₂ O, and BaO can be used.

The organic electroluminescent device according to the present invention can be used for a display device, a display device, an element for a single color or a white light, and the like.

1 is a cross-sectional view showing the structure of an organic electroluminescent device of the present invention. The organic electroluminescent device according to the present invention includes an anode 20, a hole transport layer 40, an organic emission layer 50, an electron transport layer 60 and a cathode 80, The electron injecting layer 70 may be further formed. In addition, one or two intermediate layers may be further formed, or a hole blocking layer or an electron blocking layer may be further formed.

Referring to FIG. 1, the organic electroluminescent device of the present invention and its manufacturing method will be described as follows. First, an anode electrode material is coated on the substrate 10 to form an anode 20. Here, as the substrate 10, an organic substrate or a transparent plastic substrate which is excellent in transparency, surface smoothness, ease of handling, and waterproofness is used as a substrate used in a conventional organic EL device. As the material for the anode electrode, indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO ₂ ), zinc oxide (ZnO) and the like which are transparent and excellent in conductivity are used.

A hole injection layer 30 is formed on the anode 20 by vacuum thermal deposition or spin coating. Subsequently, a hole transport layer 40 is formed by vacuum thermal deposition or spin coating on the hole transport layer 30 above the hole injection layer 30. A hole blocking layer (not shown) is selectively formed on the organic light emitting layer 50 by a vacuum deposition method or a spin coating method to form a thin film on the organic light emitting layer 50 can do. In the case where holes are injected into the cathode through the organic light-emitting layer, the lifetime and the efficiency of the device are reduced, and thus the hole blocking layer plays a role of preventing such a problem by using a material having a very low HOMO (Highest Occupied Molecular Orbital) level . In this case, the hole blocking material to be used is not particularly limited, but it is required to have an ionization potential higher than that of the light emitting compound while having electron transporting ability. Typically, BAlq, BCP, TPBI and the like can be used.

After the electron transport layer 60 is deposited on the hole blocking layer by a vacuum deposition method or a spin coating method, an electron injection layer 70 is formed, and a cathode forming metal is deposited on the electron injection layer 70 in a vacuum heat- And the cathode 80 is formed by vapor deposition to complete the organic EL device. Here, as the metal for forming the cathode, lithium, magnesium, aluminum, aluminum-lithium, calcium, magnesium-magnesium, Mg-Ag), and a transmissive cathode using ITO or IZO can be used to obtain a top light-emitting device.

According to another embodiment of the present invention, at least one layer selected from the hole injecting layer, the hole transporting layer, the electron blocking layer, the light emitting layer, the hole blocking layer, the electron transporting layer and the electron injecting layer is formed by a single molecular deposition method or a solution process And the organic electroluminescent device according to the present invention can be used for a display device, a display device, and a monochromatic or white illumination device.

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. It will be apparent, however, to those skilled in the art that these embodiments are for further illustrating the present invention and that the scope of the present invention is not limited thereby.

<Examples>

Synthesis Example 1. Synthesis of [Formula 2]

(1) [Intermediate 1-a] was synthesized according to Reaction Scheme 1 below.

[Reaction Scheme 1]

[Intermediate 1-a]

(0.284 mol) of 2,7-dibromo-9,9'-dimethylfluorene was placed in a reaction vessel containing 1 L of tetrahydrofuran. The temperature was lowered to -78 ° C in the nitrogen state. 177.5 ml (0.284 mol) of n-butyllithium 1.6 M was slowly added dropwise. After completion of dropwise addition, the mixture was stirred for about 1 hour. 38.4 g (0.369 mol) of trimethyl borate was slowly added thereto, and then the temperature was raised to room temperature. 2 N hydrochloric acid was added until acidic. The organic layer was distilled under reduced pressure and recrystallized from hexane. Filtered and dried to obtain 71 g (yield 78.9%) of Intermediate 1-a.

(2) [Intermediate 1-b] was synthesized according to Reaction Scheme 2 below.

[Reaction Scheme 2]

[Intermediate 1-b]

[Intermediate 1-a] 71 g (0.244 mol), 4- bromo-2-iodo-aniline 73.4 g (0.246 mol), tetrakis (triphenylphosphine) palladium _{(Pd (PPh 3) 4)} 8.2g (4 mmol ) And potassium carbonate (61.91 g, 0.448 mol) were placed in a round bottom flask containing 350 ml of 1,4-dioxane, 350 ml of toluene and 140 ml of water. The mixture was refluxed for 24 hours, cooled to room temperature and extracted, and the organic layer was concentrated under reduced pressure. The product was separated by column chromatography, recrystallized from toluene and methanol, and dried to obtain 63 g (yield: 63.5%) of Intermediate 1-b

(3) [Intermediate 1-c] was synthesized according to the following Reaction Scheme 3.

[Reaction Scheme 3]

[Intermediate 1-c]

63 g (0.142 mol) of Intermediate 1-b, 24.5 g (0.355 mol) of sodium nitrite, 59 g (0.355 mol) of potassium iodide, 0.75 L of acetonitrile and 0.75 L of water were added to the reaction vessel and stirred. The mixture was stirred at room temperature for 24 hours. After the extraction, the organic layer was distilled off under reduced pressure, and the resultant was subjected to column separation to obtain 65 g (yield: 82.5%) of Intermediate 1-c.

(4) [Intermediate 1-d] was synthesized according to Reaction Scheme 4 below.

[Reaction Scheme 4]

[Intermediate 1-d]

60.4 g (0.109 mol) of [Intermediate 1-c] were placed in a reaction vessel containing 0.6 L of tetrahydrofuran. The temperature was lowered to -78 ° C in the nitrogen state. 59.1 ml (0.095 mol) of n-butyllithium 1.6 M was slowly added dropwise. After completion of dropwise addition, the mixture was stirred for about 1 hour. 15 g (0.073 mol) of dibenzo subrene was added thereto, and the temperature was raised to room temperature. The organic layer was concentrated under reduced pressure, and then charged into a reaction vessel containing 600 ml of acetic acid. 1 ml of concentrated hydrochloric acid was added, and the mixture was refluxed for 1 hour to filter out the solid. The reaction mixture was separated by column, recrystallized with toluene methanol, and dried to obtain 12 g of [intermediate 1-d] (yield: 26.8%).

(5) [Formula 2] was synthesized by the following Reaction Scheme 5.

[Reaction Scheme 5]

(2)

To a round bottom flask was added 5 g (8 mmol) of Intermediate 1-d, 3.3 g (19 mmol) of diphenylamine, 0.04 g (0.2 mmol) of palladium acetate {Pd (OAc) (24 mmol), 0.06 g (0.2 mmol) of triturated butylphosphine (50%) and 50 ml of toluene, and the mixture was reacted at 100 ° C for 2 hours. When the reaction was completed, the filtrate was concentrated after the filtration and then separated by column chromatography. After recrystallization from toluene and methanol, the resulting solid was filtered and dried to obtain 2.7 g (yield 42%) of a pale yellow solid of Formula 2.

MS: m / z 792 [M] ^&lt; ⁺ & gt ^;

Synthesis Example 2. Synthesis of [Formula 3]

Synthesis was conducted in the same manner as in Synthesis Example 1, except that di-para-tolueneamine was used instead of diphenylamine in the above Reaction Scheme 5 to obtain 1.8 g (yield 32%) of a pale yellow solid.

MS: m / z 848 [M] ^&lt; ⁺ & gt ^;

Synthesis Example 3. Synthesis of [Formula 5]

Synthesis was conducted in the same manner as in Synthesis Example 1, except that 3-methyldiphenylamine was used instead of diphenylamine in the above Reaction Scheme 5 to obtain 1.9 g (yield: 27%) of a pale yellow solid.

MS: m / z 820 [M] ^&lt; ⁺ & gt ^;

Synthesis Example 4. Synthesis of [Formula 8]

Synthesis was conducted in the same manner as in Synthesis Example 1, except that N-phenyl-1-naphthylamine was used instead of diphenylamine in the above Reaction Scheme 5 to obtain 1.1 g (yield 18%) of pale yellow solid.

MS: m / z 892 [M] ^&lt; ⁺ & gt ^;

Synthesis Example 5. Synthesis of [Formula 9]

Synthesis was conducted in the same manner as in Synthesis Example 1, except that N-phenyl-4-biphenylamine was used instead of diphenylamine in the above Reaction Scheme 5 to obtain 3.1 g (yield 49%) of a pale yellow solid.

MS: m / z 944 [M] ^&lt; ⁺ & gt ^;

Synthesis Example 6. Synthesis of [Formula 23]

(1) [Intermediate 6-a] was synthesized by the following Reaction Scheme 6.

[Reaction Scheme 6]

[Intermediate 6-a]

176 g (1.32 mol) of aluminum chloride and 573 g (3.6 mol) of bromine were stirred in a reaction vessel at 0 占 폚 for 15 minutes. 134.6 g (0.6 mol) of dibenzosuberone was slowly added thereto, followed by stirring for 30 minutes. The temperature was slowly raised to room temperature, followed by extraction with water and ethyl acetate, and the organic layer was concentrated under reduced pressure. The reaction mixture was separated by column, recrystallized with hexane and then dried to obtain 87 g (37.9%) of Intermediate 6-a.

(2) [Intermediate 6-b] was synthesized according to the following Reaction Scheme 7.

[Reaction Scheme 7]

[Intermediate 6-b]

76.4 g (0.2 mol) of [Intermediate 6-a] and 91.6 g (0.44 mol) of pollution were placed in a reaction vessel containing 180 ml of phosphorus chloride, and the mixture was heated to 90 ° C and stirred for 6 hours. After the temperature was lowered to room temperature, the reaction solution was slowly added to a mixed solution containing 400 ml of dichloromethane, 200 ml of methanol and 200 ml of ice water. The mixture was stirred for 12 hours, the crystals were filtered, washed with diethyl ether, and the solid was recrystallized using dichloromethane and hexane. The solid was filtered and dried to obtain 45 g (yield: 59.2%) of [intermediate 6-b].

(3) [Intermediate 6-c] was synthesized according to the following Reaction Scheme 8.

[Reaction Scheme 8]

[Intermediate 6-c]

41.4 g (0.178 mol) of 2-bromobiphenyl was placed in a reaction vessel containing 0.4 L of tetrahydrofuran. The temperature was lowered to -78 ° C in the nitrogen state. 96.2 ml (0.154 mol) of n-butyllithium 1.6 M was slowly added dropwise. After completion of dropwise addition, the mixture was stirred for about 1 hour. 15 g (0.073 mol) of [Intermediate 6-b] was slowly added and the temperature was raised to room temperature. The organic layer was concentrated under reduced pressure, and then placed in a reaction vessel containing 400 ml of acetic acid. 1 ml of concentrated hydrochloric acid was added and the mixture was refluxed for 1 hour. The solid was filtered off at room temperature, and the resulting mixture was subjected to column separation. Recrystallization from dichloromethane and hexane was followed by drying to obtain 55 g of [intermediate 6-b] (yield 90%).

(4) [Intermediate 6-d] was synthesized according to the following Reaction Scheme 9.

[Reaction Scheme 9]

[Intermediate 6-d]

55 g (0.107 mol) of [Intermediate 6-c] were placed in a reaction vessel containing 0.5 L of tetrahydrofuran. The temperature was lowered to -78 ° C in the nitrogen state. 66.6 ml (0.107 mol) of n-butyllithium 1.6 M was slowly added dropwise. After completion of dropwise addition, the mixture was stirred for about 1 hour. 14.4 g (0.138 mol) of trimethyl borate was slowly added thereto, and then the temperature was raised to room temperature. 2 N hydrochloric acid was added until acidic. The organic layer was distilled under reduced pressure and recrystallized from hexane. After filtration and drying, 29 g (yield: 56.6%) of intermediate 6-d was obtained.

(5) [Intermediate 6-e] was synthesized by the following Reaction Scheme 10.

[Reaction Scheme 10]

[Intermediate 6-e]

To the reaction vessel, a mixture of 29 g (0.060 mol) of Intermediate 6-b, 22.6 g (0.066 mol) of methyl 5-bromo-2-iodobenzoate and 1.4 g (0.06 mol) of tetrakistriphenylphosphine palladium (1.2 mmol) and potassium carbonate (16.6 g, 0.12 mol) were placed in a round bottom flask containing 30 ml of 1,4-dioxane, 30 ml of toluene and 15 ml of water. The mixture was refluxed for 24 hours, cooled to room temperature and extracted, and the organic layer was concentrated under reduced pressure. The reaction mixture was separated by column chromatography, recrystallized with dichloromethane and hexane, and dried to obtain 25 g (yield: 63.8%) of Intermediate 6-e.

(6) [Intermediate 6-f] was synthesized according to Reaction Scheme 11 below.

[Reaction Scheme 11]

[Intermediate 6-f]

25 g (0.04 mol) of [Intermediate 1-e] was placed in a reaction vessel containing 250 ml of tetrahydrofuran. 3 M Methylmagnesium iodide 40 mL (0.12 mol) was slowly added dropwise. After refluxing overnight, the temperature was lowered to room temperature. The aqueous ammonium chloride solution was slowly added. The organic layer was concentrated under reduced pressure, and then charged into a reaction vessel containing 250 ml of acetic acid. 1 ml of concentrated hydrochloric acid was added and the mixture was refluxed for 1 hour to filter the solid. The reaction mixture was separated by column, recrystallized from dichloromethane and hexane, and dried to obtain 7 g of [intermediate 6-f] (yield: 27.6%).

(7) [Chemical Formula 23] was synthesized by the following Reaction Scheme 12.

[Reaction Scheme 12]

(23)

To a round bottom flask was added 4 g (6 mmol) of intermediate 6-f, 2.6 g (19 mmol) of diphenylamine, 0.03 g (0.1 mmol) of palladium acetate {Pd (OAc) 2, 1.9 g of sodium tertiary butoxide (19 mmol), 0.03 g (0.1 mmol) of triturated butylphosphine (50%) and 50 ml of toluene, and the mixture was reacted at 100 ° C for 2 hours. When the reaction was completed, the filtrate was concentrated after the filtration and then separated by column chromatography. After recrystallization from toluene and methanol, the resulting solid was filtered and dried to obtain 1.5 g (yield: 29%) of a pale yellow solid of the formula (23).

MS: m / z 792 [M] ^&lt; ⁺ & gt ^;

Synthesis Example 7. Synthesis of [Formula 24]

Synthesis was conducted in the same manner as in Synthesis Example 6, except that 3-methyldiphenylamine was used instead of diphenylamine in the above Reaction Scheme 12 to obtain 0.9 g (yield 12%) of pale yellow solid.

MS: m / z 820 [M] ^&lt; ⁺ & gt ^;

Example 1

The ITO glass was patterned so as to have a light emitting area of 2 mm x 2 mm and then cleaned. After the ITO glass was mounted in a vacuum chamber, the base pressure was adjusted to 1 × 10 ^-7 torr, and CuPc was deposited on the ITO to form a hole injection layer having a thickness of 800 Å. On the hole injection layer, NPD was deposited to form a 300 Å thick hole transport layer. Compound ADN and [Formula 1] (3 wt%) were vacuum deposited on the hole transport layer to form a 250 Å thick light emitting layer and Alq ₃ was deposited on the light emitting layer to form a 350 Å thick electron transport layer. Then, a 5 Å thick LiF electron injection layer and a 500 Å thick Al electrode were sequentially formed to fabricate an organic light emitting device.

Examples 2 to 7

Except that the above-mentioned examples were used in place of [Formula 2], [Formula 3], [Formula 5], [Formula 8], [Formula 9], [Formula 23] and [Formula 24] An organic light emitting device was fabricated using the same method as in Example 1.

Comparative Example 1

An organic light emitting device was fabricated in the same manner as in Example 1 except that the following compound A was used in place of the compound of the formula 1 according to the present invention.

<Compound A>

Evaluation example 1

The driving voltage, current, luminance (measured at 0.4 mA), color coordinates and lifetime (T80) were measured with the PR650 Spectroscan Source Measurement Unit (PhotoResearch Co., Ltd.) according to the organic light emitting devices manufactured according to Examples 1 to 7 and Comparative Example 1 Product), and the results are shown in Table 1 below. T80 means the time required for the measured luminance to be reduced to 80% of the initial luminance and measured at 3,000 nits.

Voltage Current density Luminance CIEx CIEy T80 (mA / cm 2) (Cd / m2) Example 1 4.1 10 716 0.145 0.132 131 Implementation 2 4.3 10 802 0.134 0.157 176 Example 3 4.3 10 706 0.148 0.140 123 Implementation 4 4.2 10 699 0.149 0.137 137 Example 5 4.1 10 741 0.137 0.155 142 Example 6 4.3 10 897 0.127 0.188 198 Implementation 7 4.4 10 913 0.130 0.198 214 Comparative Example 1 4.3 10 534 0.133 0.137 45

From Table 1, it can be seen that the organic light emitting devices of Examples 1 to 7 including the fluorene derivative according to the present invention have excellent luminance and lifetime characteristics as compared with the organic light emitting device of Comparative Example 1. [

10: substrate 20: anode
30: Hole injection layer 40: Hole transport layer
50: organic light emitting layer 60: electron transporting layer
70: electron injection layer 80: cathode

Claims (9)

A fluorene derivative represented by the following formula 1:
[Chemical Formula 1]

In the above formula (1)
X &_lt; / RTI &_gt; At least one of the adjacent two selected from X &lt; ₁₈ &gt; is bonded to the L (n is an integer of 1 to 2)
The remaining X &_lt; ₁ &gt; to X &_lt; ₂ &gt; X ₁₈ is a substituted or unsubstituted arylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 24 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 24 carbon atoms, Lt; / RTI &gt; is selected from hydrogen,
R ₁ - R ₄ is a substituted or unsubstituted arylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 24 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 24 carbon atoms, Lt; / RTI &gt; is selected from hydrogen,
A ₁ to A ₂ each independently represent a substituted or unsubstituted alkyl group having 1 to 24 carbon atoms and a substituted or unsubstituted aryl group having 6 to 24 carbon atoms. The method according to claim 1,
The X ₁ To X ₁₈ , R ₁ To R &lt; ₄ &gt; and A &_lt; ₁ &gt; to A &_lt; ₂ &gt; are bonded to each other to form a saturated or unsaturated ring, or attached or fused by a pendant method. The method according to claim 1,
Wherein X ₁ to X ₁₈ , R ₁ to R ₁₈ , R ₄ and The substituents of A ₁ to A ₂ are selected from the group consisting of an arylamino group having 6 to 30 carbon atoms, an aryl group having 6 to 24 carbon atoms, an alkyl group having 1 to 24 carbon atoms, a cyano group, a halogen group, a silyl group having 1 to 24 carbon atoms, Lt; RTI ID = 0.0 &gt; fluorene &lt; / RTI &gt; derivative. The method according to claim 1,
The fluorene derivative according to claim 1, wherein the fluorene derivative is any one selected from the group consisting of the following formulas (2) to (40).
[Chemical Formula 2] &lt; EMI ID =

[Chemical Formula 5] &lt; EMI ID =

[Chemical Formula 8]

[Chemical Formula 12] [Chemical Formula 13]

[Chemical Formula 14]

[Chemical Formula 18] [Chemical Formula 19]

[Chemical Formula 20]

[Chemical Formula 23] [Chemical Formula 25]

[Chemical Formula 26]

[Chemical Formula 30] [Chemical Formula 30]

[Chemical Formula 32]

[Chemical Formula 35]

[Chemical Formula 38] [Chemical Formula 39]

Anode;
Cathode; And
An organic electroluminescent element interposed between the anode and the cathode, the organic electroluminescent element comprising a layer comprising a fluorene derivative according to any one of claims 1 to 4. 6. The method of claim 5,
Wherein the fluorene derivative is contained in the light emitting layer between the anode and the cathode. The method according to claim 6,
Wherein at least one layer selected from the group consisting of a hole injecting layer, a hole transporting layer, an electron blocking layer, a hole blocking layer, an electron transporting layer and an electron injecting layer is further interposed between the anode and the cathode. 8. The method of claim 7,
Wherein at least one layer selected from the group consisting of the hole injection layer, the hole transport layer, the electron blocking layer, the light emitting layer, the hole blocking layer, the electron transport layer and the electron injection layer is formed by a single molecular deposition method or a solution process. 6. The method of claim 5,
Wherein the organic electroluminescent device is used in a display device, a display device, or a monochromatic or white illumination device.

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