KR20170070640A - Novel compound and organic electroluminescent device including the same - Google Patents

Abstract

And a novel compound and an organic light emitting device comprising the compound as an electron transporting layer or a hole blocking layer.

Description

TECHNICAL FIELD [0001] The present invention relates to a novel compound and an organic light emitting device comprising the compound. [0002]

The present invention relates to a novel compound and an organic light emitting device comprising the compound as an electron transporting layer or a hole blocking layer.

In recent years, an organic light emitting device which can be driven by a low voltage in a self-emission type has a better viewing angle and contrast ratio than a liquid crystal display (LCD), which is a mainstream of a flat panel display device, It has been attracting attention as a next generation display device because it is advantageous in terms of power consumption and has a wide color reproduction range.

A material used as an organic material layer in an organic light emitting device can be classified into a light emitting material, a hole injecting material, a hole transporting material, an electron transporting material, and an electron injecting material depending largely on functions. The light emitting material may be classified into a polymer and a single molecule according to the molecular weight, and may be classified into a fluorescent material derived from singlet excited state of electrons according to the light emitting mechanism, a phosphorescent material derived from the triplet excited state of electrons, Can be classified as a retardation fluorescent material derived from the movement of electrons from the anti-excitation state to the singlet excitation state. The luminescent material can be classified into blue, green and red luminescent materials and yellow and orange luminescent materials necessary for realizing a better natural color depending on luminescent color. Further, in order to increase the color purity and increase the luminous efficiency through energy transfer, a host / dopant system can be used as a light emitting material. The principle is that when a small amount of dopant having a smaller energy band gap and higher luminous efficiency than a host mainly constituting the light emitting layer is mixed with a light emitting layer in a small amount, the excitons generated in the host are transported as a dopant to emit light with high efficiency. At this time, since the wavelength of the host is shifted to the wavelength band of the dopant, light of a desired wavelength can be obtained depending on the type of the dopant and host.

Various compounds have been known as materials used in such organic light emitting devices. However, organic light emitting devices using known materials have been difficult to put to practical use due to high driving voltage, low efficiency, and short lifetime. Accordingly, efforts have been made to develop an organic light emitting device having low voltage driving, high luminance, and long life using a material having excellent characteristics.

In this regard, Korean Patent Laid-Open Publication No. 2013-0060953 discloses an anthracene derivative-based organic electroluminescent device.

However, no organic electroluminescent device has been reported for achieving low voltage, high efficiency, high optical stability, and long-term stability of organic light emitting devices by using phosphine oxide-based compounds as an electron transport layer or a hole blocking layer.

The present invention is directed to a novel compound and an organic light emitting device comprising the compound as an electron transporting layer or a hole blocking layer.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

A first aspect of the invention provides a compound represented by formula 1:

[Chemical Formula 1]

Wherein R ₁ and R ₂ are each independently selected from the group consisting of hydrogen, deuterium, halogen, nitro, nitrile, substituted or unsubstituted C ₆ to C ₅₀ aryl, or substituted or unsubstituted C ₂ - a heteroaryl group of C _50, X is a substituted or unsubstituted CR ₃ or N, R ₃ is hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to C ₅₀ aryl, or A substituted or unsubstituted C ₂ to C ₅₀ heteroaryl group, L is a substituted or unsubstituted C ₆ to C ₃₀ arylene or C ₃ to C ₂₀ heteroarylene group, Z is N or CR ₃ , R ₁ may form a ring with the α carbon of the peripheral aryl (α carbon of the repeating unit m or α carbon of R ₂ ), m and n are each independently an integer of 0 to 2, provided that X is When all are CR ₃ , n is not zero.

The second aspect of the present invention provides an organic light emitting device comprising at least one organic compound layer containing a compound according to the first aspect of the present invention formed between an anode electrode and a cathode electrode.

By using the compound according to one embodiment of the present invention as an electron transporting layer or a hole blocking layer, the phosphine oxide unit included in the compound has a strong electron withdrawing effect and a lowest occupied molecular orbital (HOMO) Level, the electron transporting property and the hole blocking property are strengthened, whereby the low voltage high efficiency and high color purity of the organic light emitting device can be attained. In addition, the phosphine oxide unit prevents an increase in conjugate bond length, and thus it is possible to maintain high singlet energy and triplet energy.

In addition, the X-axis and Y-axis coordinates of the CIE chromaticity coordinate can be reduced by moving the recombination region by the compound according to one embodiment of the present invention.

The long-term device driving stability is also improved due to the low voltage, high efficiency, and high optical stability of the organic light emitting device.

FIG. 1 schematically shows a cross-section of an organic light emitting device according to an embodiment of the present invention.
2 is a graph showing current density characteristics of an organic light emitting device according to an embodiment of the present invention.
FIG. 3 is a graph illustrating current efficiency characteristics of an organic light emitting device according to an embodiment of the present invention. Referring to FIG.
FIG. 4 shows an electroluminescence spectrum of an organic light emitting device according to an embodiment of the present invention.
FIG. 5 is a graph illustrating lifetime of an organic light emitting device according to an embodiment of the present invention.
FIG. 6 is a graph showing current density characteristics of an organic light emitting device according to one embodiment of the present invention.
7 is a graph illustrating current efficiency characteristics of an organic light emitting device according to an embodiment of the present invention.
FIG. 8 shows an electroluminescence spectrum of an organic light emitting device according to an embodiment of the present invention.
9 is a graph showing lifetime of an organic light emitting device according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. It should be understood, however, that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, the same reference numbers are used throughout the specification to refer to the same or like parts.

Throughout this specification, when a part is referred to as being "connected" to another part, it is not limited to a case where it is "directly connected" but also includes the case where it is "electrically connected" do.

Throughout this specification, when a member is " on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as " including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise. The terms " about ", " substantially ", etc. used to the extent that they are used throughout the specification are intended to be taken to mean the approximation of the manufacturing and material tolerances inherent in the stated sense, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure. The word " step (or step) " or " step " used to the extent that it is used throughout the specification does not mean " step for.

Throughout this specification, the term " combination (s) thereof " included in the expression of the machine form means a mixture or combination of one or more elements selected from the group consisting of the constituents described in the expression of the form of a marker, Quot; means at least one selected from the group consisting of the above-mentioned elements.

Throughout this specification, the description of "A and / or B" means "A or B, or A and B".

 The term "aromatic heterocycle" or "heteroaryl" refers to an aromatic ring having at least one aromatic hydrocarbon group and at least one heteroatom Means that at least one carbon atom of the aromatic hydrocarbon group is substituted by a heteroatom. When the aromatic ring (aryl) or the aromatic heterocycle (heteroaryl) comprises a plurality of rings, the aromatic ring or the aromatic heterocycle includes one aromatic ring and an aromatic ring or a non-aromatic ring as an additional ring May include. The plurality of rings may include, but are not limited to, one in which at least one aromatic ring and an additional ring are bonded through one atom or a fused structure through two or more atoms. The aryl may be, for example, a benzene ring, a toluene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a pentaren ring, an indene ring, a biphenylene ring, a phenalene ring, an azene ring, A heterocyclic ring, a thiophene ring, a thienylene ring, a fluorene ring, a tetracene ring, a triphenylene ring, a pyrene ring, a chrysene ring, an ethyl-chrysene ring, a picene ring, a perylene ring, a pentaphene ring, A benzene ring, a benzene ring, a benzene ring, a benzene ring, a benzene ring, a benzene ring, a phenylene ring, a hexane ring, a rubisen ring, a coronene ring, a trinaphthylene ring, a heptaphene ring, a heptacene ring, a pyranthrene ring, A thienyl group, a triphenyl group, a terphenyl group, a 9-anthryl group, a 2-anthryl group, a 9-phenanthryl group, a 2-phenanthryl group, a 1-pyrenyl group, a chrysene group, a naphthacene group and a coronyl group However, the present invention is not limited thereto.

The heteroaryl is, for example, 1-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl, pyrazinyl, 2-pyridinyl, 3-pyridinyl, 4-pyridinyl, Isoindolyl group, 3-isoindolyl group, 4-indolyl group, 4-indolyl group, 4-indolyl group, Isoindolyl group, a 7-isoindolyl group, a 2-furyl group, a 3-furyl group, a 2-benzofuranyl group, a 3-benzofuranyl group, a 4- Isobenzofuranyl group, a 4-isobenzofuranyl group, a 5-isobenzofuranyl group, a 5-isobenzofuranyl group, a 5-isobenzofuranyl group, Isobenzofuranyl, quinolyl, 3-quinolyl, 4-quinolyl, 5-quinolyl, 6-quinolyl, 7-quinolyl, 8- Quinolyl group, 1-isoquinolyl group, 3-isoquinolyl group, 4-isoquinolyl group, 5-isoquinolyl group Isoquinolyl group, 2-quinoxalinyl group, 5-quinoxalinyl group, 6-quinoxalinyl group, 1-carbazolyl group, 2-carbazole group, A phenanthridinyl group, a 3-phenanthridinyl group, a 4-phenanthridinyl group, a 6-phenanthridinyl group, a 6-phenanthridinyl group, Acenaphthyridyl group, 1-acridinyl group, 2-acridinyl group, 3-phenanthridinyl group, 3-phenanthridinyl group, Acridine group, 4-acridine group, 9-acridine group, 1,7-phenanthroline-2-yl group, 1,7-phenanthroline-3-yl group, 1,7-phenanthroline Yl group, a 1,7-phenanthroline-6-yl group, a 1,7-phenanthroline-8-yl group, a 1,7-phenanthroline-9 -Yl group, a 1,7-phenanthroline-10-yl group, a 1,8-phenanthroline-2-yl group, a 1,8-phenanthroline- , 1,8-phenanthroline-5-yl group, 1,8-phenanthroline-6-yl group, 1,8- A 1,9-phenanthroline-2-yl group, a 1,9-phenanthroline-3-yl group, a 1,9-phenanthroline- Phenanthroline-6-yl group, a 1,9-phenanthroline-7-yl group, a 1,9-phenanthroline-5-yl group, Yl group, a 1,10-phenanthroline-3-yl group, a 1,10-phenanthroline-10-yl group, 4-yl group, 1,10-phenanthroline-5-yl group, 2,9-phenanthroline-1-yl group, 2,9-phenanthroline- A 2,9-phenanthroline-6-yl group, a 2,9-phenanthroline-7-yl group, a 2,9-phenanthroline- A 2,8-phenanthroline-4-yl group, a 2, 8-phenanthroline-1-yl group, A 2,8-phenanthroline-6-yl group, a 2,8-phenanthroline-7-yl group, a 2,8- A phenanthroline-10-yl group, a 2,7-phenanthroline-1-yl group, a 2,7-phenanthroline-3-yl group, Phenanthroline-6-yl group, 2,7-phenanthroline-8-yl group, 2,7-phenanthroline-9-yl group, 2,7-phenanthrol 2-phenothiazine, 2-phenothiazine, 2-phenothiazine, 3-phenothiazine, 4-phenothiazine, 10-phenothiazine, Phenoxadinyl group, 2-oxazoyl group, 4-oxazolyl group, 4-thiazolidinyl group, 4-thiazolidinyl group, A 2-thienyl group, a 2-methylpyrrol-1-yl group, a 2-methylpyrrolidinyl group, a 2-methylpyridazinyl group, Methylpyrrol-4-yl group, 3-methylpyrrol-1-yl group, 3-methylpyrrol-2-yl group, 3- Methylpyrrol-5-yl group, 2-t-butylpyrrol-4-yl group, 3- Indolyl group, 2-methyl-3-indolyl group, 4-methyl-3-indolyl group, 2- butyryl group, t-butyl-1-indolyl group, 2-t-butyl-3-indolyl group and 4-t-butyl-3-indolyl group.

The term "heteroatom" as used herein throughout the specification refers to atoms other than carbon and hydrogen atoms, for example, the heteroatom may be Si, Se, N, O, S, P, As, F, Cl, Br And < RTI ID = 0.0 > I, < / RTI >

Throughout this specification, the term " halogen "or" halo " means that the halogen atom belonging to group 17 of the periodic table is included in the compound as a form of a functional group, and may be, for example, chlorine, bromine, fluorine or iodine , But may not be limited thereto.

Throughout the present specification, the term "substituted or unsubstituted" is CN, hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to C ₅₀ aryl group, or a substituted or unsubstituted C ₂ To C ₅₀ heteroaryl groups, and the like.

A first aspect of the invention provides a compound represented by formula 1:

 [Chemical Formula 1]

Wherein R ₁ to R ₂ are each independently selected from the group consisting of hydrogen, deuterium, halogen, nitro, nitrile, substituted or unsubstituted C ₆ to C ₅₀ aryl, or substituted or unsubstituted C ₂ - a heteroaryl group of C _50, X is a substituted or unsubstituted CR ₃ or N, R ₃ is hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to C ₅₀ aryl, or A substituted or unsubstituted C ₂ to C ₅₀ heteroaryl group, L is a substituted or unsubstituted C ₆ to C ₃₀ arylene or C ₃ to C ₂₀ heteroarylene group, Z is N or CR ₃ , R ₁ may form a ring with the α carbon of the peripheral aryl, m and n are each independently an integer of 0 to 2, provided that when X is all CR ₃ , n is not 0. At this time, α carbon of the peripheral aryl is α α carbon of carbon or R ₂ in the repeating unit m.

In one embodiment of the present invention, when R ₁ forms a ring with the α carbon of the peripheral aryl, the rigidity of the molecule may be increased to have high thermal stability.

In one embodiment of the present invention, when the compound represented by Formula 1 is used as an electron transporting material, the electron transport increase (LUMO) energy level is lowered, so that electrons are easily transported. The efficiency of the organic light emitting device can be increased.

In one embodiment of the present invention, by using the compound represented by Formula 1 as a hole blocking layer, holes can be prevented from leaking into the electron transporting layer, and the holes can remain in the light emitting layer to increase the efficiency of the organic light emitting device.

In one embodiment herein, each of R ₁ to R ₃ may include, but is not limited to, independently selected from the following substituents:

Of the above formula, - * is a bonding site, Y are each independently, a C, N, or CR _4, R ₄ is hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to C ₅₀ aryl group, or a substituted or unsubstituted C ₂ to C ₅₀ heteroaryl group.

In one embodiment herein, L may be selected from, but not limited to, the following substituents:

Of the above formula, - * is a bonding site, Y are each independently, a C, N, or CR _4, R ₄ is hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to C ₅₀ aryl group, or a substituted or unsubstituted C ₂ to C ₅₀ heteroaryl group.

In one embodiment herein, the compound may include, but is not limited to, those represented by any of the following formulas:

In one embodiment herein, the compound may be, but is not limited to, those prepared by the process for preparing a compound represented by the following Reaction Scheme 1:

 [Reaction Scheme 1]

Wherein R ₁ to R ₂ are each independently selected from the group consisting of hydrogen, deuterium, halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to C ₅₀ aryl, or a substituted or unsubstituted C ₂ - a heteroaryl group of C _50, X is a substituted or unsubstituted CR ₃ or N, R ₃ is hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to C ₅₀ aryl, or A substituted or unsubstituted C ₂ to C ₅₀ heteroaryl group, L is a substituted or unsubstituted C ₆ to C ₃₀ arylene or C ₃ to C ₂₀ heteroarylene group, Z is N or CR ₃ , R ₁ may form a ring with the α carbon of the peripheral aryl, m and n are each independently an integer of 0 to 2, provided that when X is all CR ₃ , n is not 0. At this time, α carbon of the peripheral aryl is α α carbon of carbon or R ₂ in the repeating unit m.

In one embodiment of the present invention, when R ₁ forms a ring with the α carbon of the peripheral aryl, the rigidity of the molecule may be increased to have high thermal stability.

In one embodiment herein, each of R ₁ to R ₃ may include, but is not limited to, independently selected from the following substituents:

Of the above formula, - * is a bonding site, Y are each independently, a C, N, or CR _4, R ₄ is hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to C ₅₀ aryl group, or a substituted or unsubstituted C ₂ to C ₅₀ heteroaryl group.

In one embodiment herein, L may be selected from, but not limited to, the following substituents:

Of the above formula, - * is a bonding site, Y are each independently, a C, N, or CR _4, R ₄ is hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to C ₅₀ aryl group, or a substituted or unsubstituted C ₂ to C ₅₀ heteroaryl group.

The second aspect of the present invention provides an organic light emitting device comprising at least one organic compound layer containing a compound according to the first aspect of the present invention formed between an anode electrode and a cathode electrode.

Although a detailed description of the organic light emitting device according to the second aspect of the present invention is omitted from the description of the first aspect of the present invention, the description of the first aspect of the present invention is not limited to the second aspect of the present invention As shown in FIG.

In one embodiment of the present invention, the organic light emitting device may include one or more organic layers including a compound represented by Formula 1.

In one embodiment of the present invention, the organic material layer including the compound represented by Formula 1 may be an electron transport layer or a hole blocking layer. At this time, the compound may be used alone or as a known electron injecting material or a compound for an electron transporting material as an electron transporting material, but the present invention is not limited thereto.

In one embodiment of the present invention, the organic light emitting diode includes a hole injection layer (HIL), a hole transport layer (HTL), a light emitting layer (EML), an electron transport layer (ETL) Layer (EIL) or the like, but may not be limited thereto.

In this regard, FIG. 1 schematically shows a cross section of an organic light emitting device according to an embodiment of the present invention.

1, an organic light emitting device according to an embodiment of the present invention includes an anode electrode 11 formed on a substrate 10, a hole injection layer 12 formed on the anode electrode 11, A light emitting layer 14 formed on the hole transporting layer 13, an electron transporting layer 15 formed on the light emitting layer 14, an electron transporting layer 15 formed on the electron transporting layer 15, a hole transporting layer 13 formed on the electron transporting layer 12, An injecting layer 16, and a cathode electrode 17 formed on the electron injecting layer 16, but the present invention is not limited thereto.

The organic light emitting device according to one embodiment of the present invention can be manufactured by the following method.

First, the anode electrode 11 is formed by depositing an anode electrode material having a low work function so that holes can be injected onto the substrate 10.

In one embodiment of the present invention, the substrate 10 is not particularly limited as long as it is a substrate used in a conventional organic light emitting device. In particular, the substrate 10 can be used in a variety of applications, such as a mechanical strength, thermal stability, transparency, surface smoothness, But may include, but is not limited to, an excellent glass substrate or a transparent plastic substrate.

In one embodiment of the present invention, the anode electrode 11 is made of transparent indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO ₂ ), zinc oxide (ZnO) But are not limited to, those selected from the group consisting of combinations. The anode electrode material may be deposited by a conventional anode electrode forming method, for example, but may be deposited on a substrate by a vapor deposition method or a sputtering method, but the present invention is not limited thereto.

The hole injecting layer 12 may be formed on the anode electrode 11 by a vacuum deposition method, a spin coating method, a casting method, or a Langmuir-Blodgett (LB) method. . Preferably, the hole injection layer 12 may be formed by a vacuum deposition method which is easy to obtain a uniform film quality and hardly generates pin holes. For example, when the hole injection layer 12 is formed by the vacuum deposition method, the compound used as the material of the hole injection layer 12 or the structure and thermal properties of the desired hole injection layer 12 The deposition conditions generally vary between about 50 캜 and about 500 캜, a vacuum of about 10 ^-8 torr to about 10 ^-3 torr, a deposition rate of about 0.01 Å / sec to about 100 Å / sec, and It is preferred to deposit in a layer thickness range of from about 10 A to about 5 mu m.

In one embodiment of the present invention, the material of the hole injection layer 12 is not particularly limited and may be a phthalocyanine compound such as copper phthalocyanine disclosed in U.S. Patent No. 4,356,429, or a star burst type amine derivative TCTA [4, MTDAPA [4,4 ', 4 "-tris (3-methylphenylamino) triphenylamine], m-MTDAPB [ , 4 "-tris (3-methylphenylamino) phenoxy benzene], or ^{HI-406 [N 1, N} 1 '- ( biphenyl-4,4'-diyl) bis (N ¹ - (naphthalen-1-yl ) -N ⁴ , N ⁴ -diphenylbenzene-1,4-diamine] may be used as the hole injection layer material, but the present invention is not limited thereto.

Next, the hole transport layer 13 may be formed on the hole injection layer 12 by a method such as a vacuum deposition method, a spin coating method, a casting method, or an LB method. However, the present invention is not limited thereto. Preferably, the hole transport layer 13 may be formed by a vacuum vapor deposition method which is easy to obtain a uniform film quality and hardly generates pin holes. For example, in the case where the hole transport layer 13 is formed by the vacuum deposition method, the deposition conditions vary depending on the compound used, but it is generally preferable to select the deposition conditions under the same conditions as the deposition conditions of the hole injection layer .

The material of the hole transporting layer 13 is not particularly limited and may be selected from commonly known materials used as the hole transporting layer 13. Specifically, the material of the hole transporting layer 13 is a carbazole derivative such as N-phenylcarbazole, polyvinylcarbazole, or the like, a carbazole derivative such as N, N'-bis (3-methylphenyl) -N, Aromatic condensed rings such as 1-biphenyl-4,4'-diamine (TPD) or N, N'-di (naphthalen-1-yl) -N, N'-diphenylbenzidine A typical amine derivative and the like may be used.

Then, the light emitting layer 14 may be formed on the hole transport layer 13 by a method such as a vacuum evaporation method, a spin coating method, a casting method, an LB method, or the like, but the present invention is not limited thereto. Preferably, the light-emitting layer 14 may be formed by a vacuum deposition method which is easy to obtain a uniform film quality and is difficult to generate pin holes. In the case where the light emitting layer 14 is formed by the vacuum deposition method, the deposition conditions are different depending on the compound used, but it is generally preferable to select the deposition conditions in substantially the same range as the deposition conditions of the hole injection layer. A well-known host or dopant may be used for the material of the light emitting layer 14. [ For instance, the fluorescent dopant is Idemitsu Co. (Idemitsu Co.), available IDE102 or IDE105, or BD142 (N ^6, N ¹² in-bis (3,4-dimethylphenyl) -N ^6, N ¹² - D-mesityl Cri The phosphorescent dopant may be a green phosphorescent dopant {Ir (ppy) ₃ [tris (2-phenylpyridine) iridium]}, a blue phosphorescent dopant F ₂ Irpic {iridium (III) Bis [4,6-difluorophenyl) -pyridinate-N, C2 '] picolinate)}, UDC's red phosphorescent dopant RD61 and the like can be vacuum vacuum deposited (doped). The doping concentration of the dopant is not particularly limited, but is preferably doped with about 0.01 to about 15 parts by weight of the dopant relative to 100 parts by weight of the host.

In addition, when the light emitting layer 14 is used together with a phosphorescent dopant, a hole blocking material (HBL) is further laminated by a vacuum evaporation method or a spin coating method to prevent the triplet excitons or holes from diffusing into the electron transporting layer . The hole blocking material that can be used at this time is not particularly limited, and any known hole blocking material may be selected and used. For example, the hole blocking material may be an oxadiazole derivative, a triazole derivative, a phenanthroline derivative, or a hole blocking material described in Japanese Patent Application Laid-Open No. 11-329734 (A1). Typically, Balq [ Bisphenols such as bis (8-hydroxy-2-methylquinolinonato) -aluminum biphenoxide] or phenanthrolines based compounds such as UDC BCP (bassocouroin) But may not be limited thereto.

Next, the electron transport layer 15 is formed on the light emitting layer 14.

The electron transport layer 15 may be formed by a method such as a vacuum evaporation method, a spin coating method, a casting method, or an LB method, but the present invention is not limited thereto. Preferably, the electron transport layer 15 may be formed. For example, in the case where the electron transport layer 15 is formed by the vacuum deposition method, the deposition conditions vary depending on the compound used, but it is generally preferable to select the deposition conditions under the same conditions as the deposition conditions of the hole injection layer .

In one embodiment of the present invention, the electron transport layer 15 serves to stably transport electrons injected from the electron injection electrode (cathode electrode 17), and the compound represented by Formula 1 is used alone Or a known electron transport layer material may be mixed and used.

In one embodiment of the present invention, by using the compound represented by Formula 1 as the electron transport layer 15, the electron transporting property is enhanced by the phosphine oxide unit contained in the compound, Voltage characteristics and high-efficiency characteristics. In addition, the recombination region is shifted by the phosphine oxide unit, so that the color coordinates x, y can be reduced. Further, the phosphine oxide unit prevents an increase in the conjugated bond length, and it is possible to maintain a high triplet energy.

In one embodiment of the present invention, an electron injection layer (EIL) 16, which is a material having a function of facilitating the injection of electrons from the cathode (cathode electrode 17), is laminated on the electron transport layer 15 But may not be limited thereto. For example, the electron injection layer 16 material may include, but is not limited to, LiF, NaCl, CsF, Li ₂ O, BaO, and combinations thereof .

In addition, although not shown, in one embodiment of the present invention, the compound represented by Formula 1 may be additionally included between the light emitting layer 14 and the electron transporting layer 15, . By using the compound represented by Chemical Formula 1 as the hole blocking layer, it is possible to prevent the holes from leaking into the electron transporting layer, and the holes can remain in the light emitting layer to increase the efficiency of the organic light emitting element.

Finally, a metal for forming a cathode may be formed on the electron injection layer 16 by a vacuum evaporation method or a sputtering method, and used as the cathode electrode 17. The cathode electrode 17 may include, but is not limited to, lithium, magnesium, aluminum, calcium, indium, silver, gold, and combinations thereof. The cathode 17 may be a transmissive cathode using ITO, IZO, SnO ₂ , or ZnO to obtain a top emission device, but the present invention is not limited thereto.

The organic light emitting device according to one embodiment of the present invention may have various structures as well as an anode, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and a cathode structure, Layer or an intermediate layer of two layers may be additionally formed.

The thickness of each organic layer formed according to one embodiment herein may be controlled depending on the required degree, preferably it may be from about 10 nm to about 1,000 nm, more preferably from about 20 nm to about 150 nm Nm. ≪ / RTI >

In one embodiment of the present invention, the organic material layer including the compound represented by the formula (1) has a uniform surface and excellent shape stability because the thickness of the organic material layer can be controlled by the molecular unit.

Hereinafter, embodiments and examples of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to these embodiments and examples and drawings.

[ Manufacturing example ]

1. Synthesis of intermediates

1-1. Synthesis of Intermediate 1

In a 250 mL flask, 24 g of 3,5-dibromopyridine and 100 mmol of thiophene were dissolved in 250 mL of THF. Then, 48 mL of n- BuLi (2.5 M) was added at -78 ° C. and maintained for 1 hour. 18 mL of phosphine chloride was added, and the mixture was stirred at room temperature for 12 hours. When the reaction was completed, it was extracted three times with MC and distilled water. The water was removed with anhydrous sodium sulfate and the solvent was removed to give a solid. The obtained solid was dissolved in MC and H ₂ O ₂ , stirred for 3 hours, and then extracted three times with MC and distilled water. Subsequently, water was removed with anhydrous sodium sulfate, and hexane: MC (1: 1) was subjected to column separation using a mobile phase to obtain 25 g of a white solid.

1-2. Synthesis of intermediate 2

The following compounds were synthesized using the same procedure for the synthesis of Intermediate 1 but using 1-chloro-3-iodobenzene instead of 3,5-dibromopyridine:

1-3. Synthesis of intermediate 3

The following compound was synthesized using 2-chloro-4-iodobenzene instead of 3,5-dibromopyridine, using the same method as that for the synthesis of intermediate 1 above:

1-4. Synthesis of Intermediate 4

The following compounds were synthesized using the same procedure for the synthesis of Intermediate 1 but using 5-bromo-2-chloropyridine instead of 3,5-dibromopyridine:

1-5. Synthesis of Intermediate 5

24 g of 1,3,5-tribromobenzene, 25 g of 9,9-dimethylfluorene-2-boronic acid, 25 g of tetrakis (triphenylphosphine) palladium ( 0), 300 mL of dioxane, and 25 g of sodium carbonate were dissolved in 100 mL of water, and the mixture was heated and stirred under reflux for 24 hours. When the reaction was completed, the reaction mixture was cooled to room temperature, and the precipitated crystals were separated by filtration. The filtrate-separated crystals were recrystallized from toluene to obtain 23 g (67%) of white solid 2- (3,5-dibromophenyl) -9,9-dimethylfluorene.

Subsequently, 20 g of 2- (3,5-dibromophenyl) -9,9-dimethylfluorene obtained above, 27 g of Reactant 5, 20 g of tetrakis (triphenylphosphine) palladium Phenylphosphine) palladium (0), 300 mL of dioxane, and 20 g of sodium carbonate were dissolved in 100 mL of water, and the mixture was heated and stirred under reflux for 24 hours. When the reaction was completed, the reaction mixture was cooled to room temperature, and the precipitated crystals were separated by filtration. The filtrate-separated crystals were recrystallized from toluene to finally yield 20 g (71%) of a white solid:

1-6. Synthesis of Intermediate 6

The following compounds were synthesized using Reactant 1 instead of Reactant 5, using the same procedure as for the synthesis of Intermediate 5:

1-7. Synthesis of Intermediate 7

The following compounds were synthesized using reactant 2 instead of reactant 5, using the same procedure as for the synthesis of intermediate 5 above:

MS (EI) (m / z) [M ^< ⁺ &^gt;] [

1-8. Synthesis of Intermediate 8

Dibromo-9,9-dimethylfluorene, 17 g of Reactant 2, 0.9 g of tetrakis (triphenylphosphine) palladium (0), and 10 g of 1,3-dibromo-9,9-dimethylfluorene were placed in a 250 mL flask under argon or nitrogen atmosphere. 150 mL of dioxane, and 14 g of sodium carbonate were dissolved in 50 mL of water, and the mixture was heated and stirred while being refluxed for 24 hours. When the reaction was completed, the reaction mixture was cooled to room temperature, and the precipitated crystals were separated by filtration. The filtrate-separated crystals were recrystallized from toluene to give 12 g (66%) of the following white solid:

1-9. Synthesis of intermediate 9

The following compounds were synthesized using Reactant 1 instead of Reactant 2, using the same procedure for the synthesis of Intermediate 8 as above:

1-10. Synthesis of intermediate 10

To a 250 mL flask was charged 17 g of 3,5-dibromocyanobenzene, 23 g of reactant, 1.5 g of tetrakis (triphenylphosphine) palladium (0), 150 mL of dioxane, and sodium carbonate 16 g in 50 mL of water, and the mixture was heated and stirred with refluxing for 24 hours. When the reaction was completed, the reaction mixture was cooled to room temperature, and the precipitated crystals were separated by filtration. The filtrate-separated crystals were recrystallized from toluene to synthesize 13 g (65%) of the following compound:

1-11. Synthesis of Intermediate 11

19.5 g of 4- (3,5-dibromophenyl) cyanobenzene, 22 g of the reactant 1, 1.7 g of tetrakis (triphenylphosphine) palladium (0) and 0.025 g of dioxane 200 were added to a 250 mL flask under an atmosphere of argon or nitrogen. and 19 g of sodium carbonate were dissolved in 70 mL of water, and the mixture was heated and stirred with refluxing for 24 hours. When the reaction was completed, the reaction mixture was cooled to room temperature, and the precipitated crystals were separated by filtration. The filtrate-separated crystals were recrystallized from toluene to obtain 14.3 g (67%) of the following compound:

1-12. Synthesis of Intermediate 12

19.5 g of 3- (3,5-dibromophenyl) cyanobenzene, 22 g of the reactant 1, 1.7 g of tetrakis (triphenylphosphine) palladium (0) and 0.3 g of dioxane 200 were added to a 250 mL flask under an atmosphere of argon or nitrogen. and 19 g of sodium carbonate were dissolved in 70 mL of water, and the mixture was heated and stirred with refluxing for 24 hours. When the reaction was completed, the reaction mixture was cooled to room temperature, and the precipitated crystals were separated by filtration. The filtrate-separated crystals were recrystallized from toluene to obtain 15.1 g (69%) of the following compound:

1-13. Synthesis of Intermediate 13

1) Synthesis of intermediate 13-1

17 g of 2,7-dibromo-9,9-dimethyl-fluorene, 23 g of Reactant 2, 1.5 g of tetrakis (triphenylphosphine) palladium (0) in a 250 mL flask under an atmosphere of argon or nitrogen , 150 mL of dioxane, and 16 g of sodium carbonate were dissolved in 50 mL of water, and the mixture was heated and stirred while being refluxed for 24 hours. When the reaction was completed, the reaction mixture was cooled to room temperature, and the precipitated crystals were separated by filtration. The filtrate-separated crystals were recrystallized from toluene to synthesize 13 g (65%) of the compound represented by the following intermediate 13-1.

2) Synthesis of intermediate 13-2

13 g of Intermediate 13-1 obtained above, 17 g of bis (pinacolato) diboron, 17 g of [1,1'-bis (diphenylphosphino) ferrocene] di 0.5 g of chloropalladium (II), 15 g of potassium acetate, and 130 mL of dioxane were placed, and the mixture was heated and stirred while being refluxed for 24 hours. When the reaction was completed, the reaction mixture was cooled to room temperature, and the precipitated crystals were separated by filtration. The filtrate-separated crystals were recrystallized from toluene to synthesize 12 g (83%) of the compound represented by the following intermediate 13-2:

1-14. Synthesis of Intermediate 14

1) Synthesis of intermediate 14-1

Using the same method as that for the synthesis of Intermediate 13-1, except that Reactant 1 was used in place of Reactant 2, a compound represented by the following Intermediate 14-1 was synthesized.

2) Synthesis of intermediate 14-2

Using the same method as that for the synthesis of Intermediate 13-2, but using Intermediate 14-1 instead of Intermediate 13-1, the following intermediate 14-2 was synthesized:

2. Reactants

The following Reactants 1 to 5 were used as reactants for producing the organic light emitting device.

[Reaction product 1]

[Reactant 2]

[Reaction product 3]

[Reaction 4]

[Reaction product 5]

3. Synthesis of Compound

3-1. Synthesis of Compound 1

4.2 g of the intermediate 1, 6.8 g of the reactant 1 and 0.6 g of tetrakis (triphenylphosphine) palladium (0) were dissolved in 50 mL of dioxane, and 7.6 g of sodium carbonate was added to a 250 mL flask under argon or nitrogen atmosphere. Dissolved in 20 mL of water was further added, and the mixture was heated and stirred for 24 hours. After the reaction, the reaction mixture was cooled to room temperature and the precipitated crystals were separated by filtration. Finally, it was recrystallized with toluene to synthesize 2.7 g (40%) of Compound 1.

_{1H-NMR (CDCl 3, 400MHz} ): δ7.46-7.50 (4H, m), 7.54-7.63 (10H, m), 7.69-7.74 (6H, m), 7.86 (1H, d), 8.04 (1H, d), 8.75-8.81 (6 H, m)

LC-MS Purity < / RTI > 99.91%, Rt = 2.67 min; MS Calcd .: 586.19; MS Found: 587.4 [M].

3-2. Synthesis of Compound 2

Compound 2 was synthesized by using the same method as Compound 1 except that Intermediate 2 was used instead of Intermediate 1.

MS Calcd.: 585.20; MS Found: 586.4 [M].

3-3. Synthesis of Compound 3

Compound 3 was synthesized by using the same method as Compound 1 except that Reactant 2 was used instead of Reactant 1.

MS Calcd .: 586.19; MS Found: 587.4 [M].

3-4. Synthesis of Compound 4

Compound 4 was synthesized by using the same method as Compound 1 except that Reactant 2 was used instead of Reactant 1 and Intermediate 2 was used instead of Intermediate 1.

MS Calcd.: 585.20; MS Found: 586.4 [M].

3-5. Synthesis of Compound 5

Compound 1 was used instead of Reaction 1, and Compound 5 was synthesized using Intermediate 2 instead of Intermediate 1.

MS Calcd .: 580.20; MS Found: 581.4 [M].

3-6. Synthesis of Compound 6

Compound 6 was synthesized by using the same method as Compound 1 but using Reaction 3 instead of Reaction 1.

MS Calcd .: 581.19; MS Found: 582.4 [M].

3-7. Synthesis of Compound 7

Compound 7 was synthesized by using the same method as Compound 1 except that Reactant 4 was used instead of Reactant 1 and Intermediate 2 was used instead of Intermediate 1.

MS Calcd .: 580.20; MS Found: 581.4 [M].

3-8. Synthesis of Compound 8

Compound 8 was synthesized by using the same method as Compound 1 except that Reactant 4 was used instead of Reactant 1.

MS Calcd .: 581.19; MS Found: 582.4 [M].

3-9. Synthesis of Compound 9

30 g of diphenylphosphine oxide, 41 g of anhydrous potassium phosphate, 3.25 g of dichloro (1,3- (bisdiphenylphosphino) propene) nickel (II) , And 250 mL of dioxane, and the mixture was heated and stirred for 24 hours while refluxing. If the reaction is no longer in progress, cool to room temperature, add 200 mL of distilled water, and extract three times with 30 mL of MC. Subsequently, water was removed with anhydrous sodium sulfate, and then hexane: ethyl acetate (1: 1) was subjected to column separation using a mobile phase to synthesize 20 g (50%) of Compound 9 as a white solid compound.

MS Calcd .: 701.79; MS Found: 701.26 [M].

3-10. Synthesis of Compound 10

Compound 10 was synthesized using Intermediate 6 instead of Intermediate 5, using the same method as for the synthesis of Compound 9.

MS Calcd .: 777.89; MS Found: 777.29 [M].

3-11. Synthesis of Compound 11

Compound 11 was synthesized using Intermediate 7 instead of Intermediate 5, using the same method as that for compound 9.

MS Calcd .: 777.89; MS Found: 777.29 [M].

3-12. Synthesis of Compound 12

10 g of Intermediate 8, 12 g of diphenylphosphine oxide, 11 g of anhydrous potassium phosphate, and 10 g of dichloro (1,3- (bisdiphenylphosphino) propene) nickel (II) were added to a 500 mL flask under argon or nitrogen atmosphere. , And 100 mL of dioxane were placed, and the mixture was heated and stirred with refluxing for 24 hours. If the reaction is no longer in progress, cool to room temperature, add 200 mL of distilled water, and extract three times with 30 mL of MC. After removing water with anhydrous sodium sulfate, hexane: ethyl acetate (1: 1) was subjected to column separation using a mobile phase to synthesize 10 g (51%) of compound 12 as a white solid compound.

MS Calcd .: 701.79; MS Found: 701.26 [M].

3-13. Synthesis of Compound 13

Compound 13 was synthesized using Intermediate 9 instead of Intermediate 8, using the same method as that for compound 12.

MS Calcd .: 701.79; MS Found: 701.26 [M].

3-14. Synthesis of Compound 14

Compound 14 was synthesized using Intermediate 10 instead of Intermediate 8, using the same method as that for compound 12.

MS Calcd .: 610.64; MS Found: 610.19 [M].

3-15. Synthesis of Compound (15)

Compound 15 was synthesized using Intermediate 11 instead of Intermediate 8, using the same method as that for compound 12.

MS Calcd.: 686.74; MS Found: 686.22 [M].

3-16. Synthesis of Compound 16

Compound 16 was synthesized using Intermediate 12 instead of Intermediate 8, using the same method as that for compound 12.

MS Calcd.: 686.74; MS Found: 686.22 [M].

3-17. Synthesis of Compound 17

12 g of Intermediate 13-2, 9.4 g of Intermediate 2, and 0.9 g of tetrakis (triphenylphosphine) palladium (0) were dissolved in 120 mL of dioxane under an atmosphere of argon or nitrogen. To a 250 mL flask was added sodium carbonate 11 g in 40 mL of water was added thereto, and the mixture was heated and stirred for 24 hours. When the reaction was completed, the solution was cooled to room temperature, and the precipitated crystals were separated by filtration. Finally, the filtrate-separated crystals were recrystallized from toluene to obtain 8 g (49%) of Compound 17.

MS Calcd .: 610.64; MS Found: 610.19 [M].

3-18. Synthesis of compound 18

Compound 18 was synthesized using Intermediate 14-2 instead of Intermediate 13-2 using the same method as Compound 17.

MS Calcd .: 610.64; MS Found: 610.19 [M].

4. Manufacture of organic light emitting device

The organic light emitting device according to this embodiment was fabricated according to the structure shown in FIG. The organic light emitting device includes an anode electrode (hole injection electrode 11) / hole injection layer 12 / hole transport layer 13 / light emitting layer 14 / electron transport layer 15 / cathode electrode (electron injection electrode 17)].

The following materials were used as the hole injecting layer 12, the hole transporting layer 13, the light emitting layer 14, and the electron transporting layer 15 of this embodiment and the comparative example:

[ Example ]

Example  One

A glass substrate coated with thin film of indium tin oxide (ITO) of 1500 Å thickness was cleaned by distilled water ultrasonication. After the distilled water was washed, it was ultrasonically washed with a solvent such as isopropyl alcohol, acetone, or methanol and dried. Subsequently, the substrate was transferred to a plasma cleaner, and then the substrate was cleaned using an oxygen plasma for 5 minutes. Subsequently, HT01 600 Å was formed as a hole injecting layer and Ref 4, 250 Å was used as a hole transporting layer on the ITO substrate by using a thermal evaporator. Subsequently, BH01: BD01 was doped with 5% as a light emitting layer to form a film with a thickness of 250 Å. Next, as the electron transport layer, the compound 1 prepared above and Liq were formed into a film having a thickness of 300 Å at a ratio of 1: 1, LiF 10 Å and aluminum (Al) 1,000 Å were formed and encapsulated in a glove box ) To prepare an organic light emitting device.

Example  2 to Example  18

An organic light emitting diode was fabricated using the same method as in Example 1, and an electron transport layer was formed using the compounds 2 to 18 prepared above.

Comparative Example  One

The same method as in Example 1 was used except that ET-01 was used instead of Compound 1 as an electron transporting layer to prepare an organic light emitting device.

Evaluation of performance of organic light emitting device

A voltage was applied to the Keithley 2400 source measurement unit to inject electrons and holes and the luminance was measured using a Konica Minolta spectrophotometer (CS-2000) The performance of the organic light emitting devices of Examples and Comparative Examples was evaluated by measuring the current density and the luminance with respect to the applied voltage under the atmospheric pressure condition. The results are shown in Table 1 below.

As can be seen from Table 1, the organic light emitting device according to the present embodiment has improved physical properties as compared with the comparative example.

2 to 5 are graphs showing current density characteristics, current efficiency characteristics, electroluminescence spectrum, and lifespan of the organic light emitting device according to the sixth embodiment.

As can be seen from FIGS. 2 to 5, the organic light emitting diode according to Example 6 exhibits excellent current density, current efficiency, electroluminescence spectrum, and long-time stability.

6 to 9 are graphs showing the current density characteristics, the current efficiency characteristics, the electroluminescence spectrum, and the lifespan of the organic light emitting device according to the eighth embodiment, respectively.

As can be seen from FIGS. 6 to 9, the organic light emitting device according to Example 8 exhibits excellent current density, current efficiency, electroluminescence spectrum, and long-time stability.

It will be understood by those of ordinary skill in the art that the foregoing description of the embodiments is for illustrative purposes and that those skilled in the art can easily modify the invention without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

10: substrate
11: anode electrode
12: Hole injection layer
13: hole transport layer
14:
15: electron transport layer
16: electron injection layer
17: cathode electrode

Claims (7)

A compound represented by the following formula (1):
[Chemical Formula 1]

In Formula 1,
R ₁ to R ₂ each independently represent hydrogen, deuterium, halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to C ₅₀ aryl group, or a substituted or unsubstituted C ₂ to C ₅₀ hetero Lt; / RTI >
X is substituted or unsubstituted CR ₃ or N,
R ₃ is hydrogen, deuterium, halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to C ₅₀ aryl group, or a substituted or unsubstituted C ₂ to C ₅₀ heteroaryl group,
L is a substituted or unsubstituted heteroaryl group of _C6 to C ₃₀ arylene or C ₃ to C ₂₀ a,
Z is N or CR < ₃ >
R ₁ may form a ring with the α carbon of the peripheral aryl (α carbon of the repeating unit m or α carbon of R ₂ )
m and n are each independently an integer of 0 to 2,
Provided that when X is all CR < ₃ >, then n is not zero.
The method according to claim 1,
Wherein each of R &_lt; ₁ > to R &_lt; ₃ > is independently selected from the following substituents:

Of the above formula, - * is a bonding site, Y are each independently, a C, N, or CR _4, R ₄ is hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to An aryl group of C ₅₀ , or a substituted or unsubstituted C ₂ to C ₅₀ heteroaryl group.
The method according to claim 1,
Wherein L is selected from the following substituents:

Of the above formula, - * is a bonding site, Y are each independently, a C, N, or CR _4, R ₄ is hydrogen, deuterium, a halogen, a nitro group, a nitrile group, a substituted or unsubstituted C ₆ to An aryl group of C ₅₀ , or a substituted or unsubstituted C ₂ to C ₅₀ heteroaryl group.
The method according to claim 1,
Wherein the compound is represented by any one of the following formulas:

The method according to claim 1,
Wherein the compound represented by Formula 1 is an electron transporting material.
An organic light emitting device comprising at least one organic layer containing a compound according to any one of claims 1 to 5 formed between an anode electrode and a cathode electrode.
The method according to claim 6,
Wherein the organic material layer is an electron transporting layer or a hole blocking layer.

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