KR20210052171A - Tertiary amine derivatives and organic electroluminescent device including the same - Google Patents

Abstract

Provided is a tertiary amine derivative which effectively absorbs a high-energy external light source in a UV region and minimizes damage to organic materials inside an organic electroluminescent device, thereby contributing to substantially improving a lifespan of the organic electroluminescent device. The organic electroluminescent device according to the present invention comprises: a first electrode; a second electrode; one or more organic material layers disposed between the first electrode and the second electrode; and a capping layer, wherein the capping layer includes the tertiary amine derivative represented by chemical formula 1. The chemical formula 1 is as defined in the detailed description of the invention.

Description

Tertiary amine derivatives and organic electroluminescent device including the same}

The present invention relates to a tertiary amine derivative and an organic electroluminescent device including the same, wherein the organic electroluminescent device including a capping layer by the tertiary amine derivative has a high refractive index characteristic and an ultraviolet absorption characteristic at the same time.

OLED (Organic Light Emitting Diodes) is attracting attention as a display using the self-luminous phenomenon in the display industry.

In OLED, in 1963, Pope et al. first attempted a study of carrier injection type electroluminescence (EL) using a single crystal of anthracene aromatic hydrocarbon. From these studies, basic mechanisms such as charge injection, recombination, exciton generation, and light emission in organic materials and electroluminescence characteristics have been understood and studied.

In particular, in order to increase luminous efficiency, various approaches such as structural change of devices and material development have been taken [Sun, S., Forrest, S. R., Appl. Phys. Lett. 91, 263503 (2007)/Ken-Tsung Wong, Org. Lett., 7, 2005, 5361-5364].

The basic structure of an OLED display is generally an anode, a hole injection layer (HIL), a hole transporting layer (HTL), an emission layer (EML), an electron transporting layer, and It is composed of a multilayer structure of ETL) and a cathode, and has a sandwich structure in which an electronic organic multilayer film is formed between two electrodes.

In general, the organic light emission phenomenon refers to a phenomenon in which electrical energy is converted into light energy by using an organic material. An organic light-emitting device using the organic light-emitting phenomenon usually has a structure including an anode, a cathode, and an organic material layer therebetween. Here, the organic material layer is often made of a multilayer structure made of different materials in order to increase the efficiency and stability of the organic light emitting device, and may include, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and the like.

In the structure of such an organic light emitting device, when a voltage is applied between two electrodes, holes are injected from the anode and electrons are injected into the organic material layer from the cathode, and excitons are formed when the injected holes and electrons meet. It glows when it falls to the ground. These organic light emitting devices are known to have characteristics such as self-luminescence, high luminance, high efficiency, low driving voltage, wide viewing angle, high contrast, and high-speed response.

Materials used as the organic material layer in the organic light-emitting device can be classified into light-emitting materials and charge transport materials, such as hole injection materials, hole transport materials, electron transport materials, and electron injection materials, according to their functions.

Light-emitting materials include blue, green, and red light-emitting materials and yellow and orange light-emitting materials necessary to realize better natural colors depending on the light-emitting color. In addition, in order to increase color purity and increase luminous efficiency through energy transfer, a host/dopant system may be used as a luminescent material. The principle is that when a small amount of a dopant having an energy band gap smaller than that of a host mainly constituting the light emitting layer and having excellent light emission efficiency is mixed in a light emitting layer, excitons generated from the host are transported to the dopant to emit light with high efficiency. At this time, since the wavelength of the host moves to the wavelength of the dopant, light having a desired wavelength can be obtained according to the type of dopant used.

In order to sufficiently express the excellent characteristics of the above-described organic light emitting device, materials that form the organic material layer in the device, such as hole injection materials, hole transport materials, light-emitting materials, electron transport materials, electron injection materials, etc., have been developed. The performance of organic light emitting devices is recognized by products.

However, as the organic light-emitting device is commercialized and time passes, the need for other characteristics other than the light-emitting characteristics of the organic light-emitting device itself has emerged.

In most cases, the organic light emitting device is exposed to an external light source, so it is in an environment exposed to ultraviolet rays having high energy. Accordingly, there is a problem that the organic material constituting the organic light emitting device is continuously affected. In order to prevent exposure to such a high-energy light source, the problem can be solved by applying a capping layer having ultraviolet absorption characteristics to the organic light-emitting device.

In general, it is known that the viewing angle characteristics of organic light-emitting devices are wide, but from the viewpoint of the light source spectrum, considerable variation occurs depending on the viewing angle. This is due to the total refractive index of the glass substrate, organic material, and electrode material constituting the organic light-emitting device and the emission wavelength of the organic light-emitting device. This is due to the occurrence of a deviation between the appropriate refractive indices.

In general, the higher the refractive index value required for blue and the longer the wavelength, the smaller the required refractive index value. Accordingly, it is necessary to develop a material forming a capping layer that simultaneously satisfies the above-mentioned ultraviolet absorption characteristics and an appropriate refractive index.

The efficiency of an organic light-emitting device can be generally divided into internal luminescent efficiency and external luminescent efficiency. The internal luminous efficiency is related to the efficiency of the formation of excitons in the organic layer in order to perform light conversion.

External luminous efficiency refers to the efficiency in which light generated in the organic layer is emitted to the outside of the organic light-emitting device.

In order to improve overall efficiency, it is necessary to increase not only the internal luminous efficiency but also the external luminous efficiency. In order to increase external luminous efficiency and prevent various problems that may be caused when exposed to daylight for a long time, development of a capping layer (CPL) compound having a new function is required. In particular, among the CPL functions, development of a capping layer (CPL) material having excellent ability to absorb light in the UV wavelength band is required.

Republic of Korea Patent Publication No. 2016-0062307 (name of the invention: organic light emitting display device including a high refractive index capping layer)

It is an object of the present invention to provide a capping layer material for an organic light-emitting device, which can improve luminous efficiency and lifetime and at the same time improve viewing angle characteristics.

It is an object of the present invention to provide a highly efficient and long-life organic electroluminescent device including a capping layer having high refractive index and heat resistance in order to improve the light extraction rate of an organic electroluminescent device.

The present invention is a first electrode; An organic material layer disposed on the first electrode; A second electrode disposed on the organic material layer; And a capping layer disposed on the second electrode, wherein the organic material layer or the capping layer includes a tertiary amine derivative represented by Formula 1 below.

[Formula 1]

In Formula 1,

Z ₁ is O or S,

n, p and q are each independently 0 or 1,

Ar ₁ and Ar ₂ are the same as each other, and a cyano group; An aryl group substituted with a cyano group; A substituted or unsubstituted dibenzofuran group; A substituted or unsubstituted dibenzothiophene group; A substituted or unsubstituted benzoxazole group; And a substituted or unsubstituted benzthiazole group; It is any one selected from among.

The compound described in the present specification may be used as a material for an organic material layer or a capping layer of an organic light-emitting device.

The compound according to the present invention exhibits ultraviolet absorption characteristics, thereby minimizing damage to organic materials in the organic light-emitting device by an external light source, and improving efficiency, low driving voltage, and/or lifespan characteristics in the organic light-emitting device.

In addition, in an organic light-emitting device using the compound described in the present specification as a capping layer, it is possible to remarkably improve the color purity according to the improvement of luminous efficiency and reduction of the half width of the emission spectrum.

1 is a first electrode 110, a hole injection layer 210, a hole transport layer 215, a light emitting layer 220, an electron transport layer 230, an electron injection layer on the substrate 100 according to an embodiment of the present invention. 235, a second electrode 120, and a capping layer 300 are sequentially stacked on an organic light-emitting device.
2 is a graph of light refraction and absorption characteristics when a tertiary amine derivative according to an embodiment of the present invention is used.

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

In the present invention, various modifications may be made and various forms may be applied, and specific embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to a specific form disclosed, it should be understood to include all changes, equivalents, or substitutes included in the spirit and scope of the present invention.

In describing each drawing, similar reference numerals have been used for similar elements. In the accompanying drawings, the dimensions of the structures are shown to be enlarged than actual for clarity of the present invention. Terms such as first and second may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another component. For example, without departing from the scope of the present invention, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. Singular expressions include plural expressions unless the context clearly indicates otherwise.

In the present application, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance the possibility of the presence or addition. Further, when a part such as a layer, film, region, plate, etc. is said to be "on" another part, this includes not only the case where the other part is "directly above", but also the case where there is another part in the middle.

In the present specification, “substituted or unsubstituted” refers to a deuterium atom, a halogen atom, a cyano group, a nitro group, an amino group, a hydroxy group, a silyl group, a boron group, a phosphine oxide group, a phosphine sulfide group, an alkyl group, an alkoxy group, an alke It may mean substituted or unsubstituted with one or more substituents selected from the group consisting of a nil group, an aryl group, a hetero aryl group, and a heterocyclic group. In addition, each of the substituents exemplified above may be substituted or unsubstituted. For example, the biphenyl group may be interpreted as an aryl group, or may be interpreted as a phenyl group substituted with a phenyl group.

In the present specification, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

In the present specification, the alkyl group may be linear, branched or cyclic. The number of carbon atoms in the alkyl group is 1 or more and 50 or less, 1 or more and 30 or less, 1 or more and 20 or less, 1 or more and 10 or less, or 1 or more and 6 or less. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, s-butyl group, t-butyl group, i-butyl group, 2-ethylbutyl group, 3, 3-dimethylbutyl group , n-pentyl group, i-pentyl group, neopentyl group, t-pentyl group, cyclopentyl group, 1-methylpentyl group, 3-methylpentyl group, 2-ethylpentyl group, 4-methyl-2-pentyl group , n-hexyl group, 1-methylhexyl group, 2-ethylhexyl group, 2-butylhexyl group, cyclohexyl group, 4-methylcyclohexyl group, 4-t-butylcyclohexyl group, n-heptyl group, 1 -Methylheptyl group, 2,2-dimethylheptyl group, 2-ethylheptyl group, 2-butylheptyl group, n-octyl group, t-octyl group, 2-ethyloctyl group, 2-butyloctyl group, 2-hexyl Siloctyl group, 3,7-dimethyloctyl group, cyclooctyl group, n-nonyl group, n-decyl group, adamantyl group, 2-ethyldecyl group, 2-butyldecyl group, 2-hexyldecyl group, 2-oxy Tyldecyl group, n-undecyl group, n-dodecyl group, 2-ethyldodecyl group, 2-butyldodecyl group, 2-hexyldodecyl group, 2-octyldodecyl group, n-tridecyl group, n-tetradecyl group, n -Pentadecyl group, n-hexadecyl group, 2-ethylhexadecyl group, 2-butylhexadecyl group, 2-hexylhexadecyl group, 2-octylhexadecyl group, n-heptadecyl group, n-octadecyl group , n-nonadecyl group, n-icosyl group, 2-ethyl icosyl group, 2-butyl icosyl group, 2-hexyl icosyl group, 2-octyl icosyl group, n-henicosyl group, n-docosyl group, n-trico A group, n-tetracosyl group, n-pentacosyl group, n-hexacosyl group, n-heptacosyl group, n-octacosyl group, n-nonacosyl group, and n-triacontyl group, etc. are mentioned, It is not limited to these.

In the present specification, a hydrocarbon ring group means any functional group or substituent derived from an aliphatic hydrocarbon ring. The hydrocarbon cyclic group may be a saturated hydrocarbon cyclic group having 5 to 20 ring carbon atoms.

In the present specification, an aryl group means any functional group or substituent derived from an aromatic hydrocarbon ring. The aryl group may be a monocyclic aryl group or a polycyclic aryl group. The number of ring carbon atoms in the aryl group may be 6 or more and 30 or less, 6 or more and 20 or less, or 6 or more and 15 or less. Examples of aryl groups include phenyl group, naphthyl group, fluorenyl group, anthracenyl group, phenanthryl group, biphenyl group, terphenyl group, quarterphenyl group, quincphenyl group, sexyphenyl group, triphenylenyl group, pyrenyl group, peryleneyl group, naphtha Although a senyl group, a pyrenyl group, a benzofluoranthenyl group, a chrysenyl group, etc. can be illustrated, it is not limited to these.

In the present specification, the fluorenyl group may be substituted, and two substituents may be bonded to each other to form a spiro structure.

In the present specification, the heteroaryl group may be a heteroaryl group including one or more of O, N, P, Si, and S as heterogeneous elements. The N and S atoms may be oxidized in some cases, and the N atom(s) may be quaternized in some cases. The number of ring carbon atoms in the heteroaryl group is 2 or more and 30 or less or 2 or more and 20 or less. The heteroaryl group may be a monocyclic heteroaryl group or a polycyclic heteroaryl group. The polycyclic heteroaryl group may have, for example, a bicyclic or tricyclic structure.

Examples of the heteroaryl group include thiophene group, furan group, pyrrole group, imidazole group, pyrazolyl group, thiazole group, oxazole group, oxadiazole group, triazole group, pyridine group, bipyridine group, pyrimidine group, triazine group , Tetrazine group, triazole group, tetrazole group, acridyl group, pyridazine group, pyrazinyl group, quinoline group, quinazoline group, quinoxaline group, phenoxazine group, phthalazine group, pyrido pyrimidine group, pyrido pyrazino Pyrazine group, isoquinoline group, cinnoly group, indole group, isoindole group, indazole group, carbazole group, N-aryl carbazole group, N-heteroaryl carbazole group, N-alkyl carbazole group, benzoxazole group, benzoimidazole group , Benzothiazole group, benzocarbazole group, benzothiophene group, benzothiophene group, benzoisothiazolyl, benzoisoxazolyl, dibenzothiophene group, thienothiophene group, benzofuran group, phenanthroline group, phenanthridine group , Thiazole group, isoxazole group, oxadiazole group, thiadiazole group, isothiazole group, isoxazole group, phenothiazine group, benzodioxole group, dibenzosilol group and dibenzofuran group, isobenzofuran group, etc. It is not limited to these. In addition, there are N-oxide aryl groups corresponding to the monocyclic hetero aryl group or polycyclic hetero aryl group, for example, quaternary salts such as a pyridyl N-oxide group and a quinolyl N-oxide group. Not limited.

In the present specification, the silyl group includes an alkyl silyl group and an aryl silyl group. Examples of the silyl group include trimethylsilyl group, triethylsilyl group, t-butyldimethylsilyl group, vinyldimethylsilyl group, propyldimethylsilyl group, triphenylsilyl group, diphenylsilyl group, phenylsilyl group, and the like. Not limited.

In the present specification, the boron group includes an alkyl boron group and an aryl boron group. Examples of the boron group include, but are not limited to, trimethyl boron group, triethyl boron group, t-butyldimethyl boron group, triphenyl boron group, diphenyl boron group, and phenyl boron group.

In the present specification, the alkenyl group may be linear or branched. The number of carbon atoms is not particularly limited, but is 2 or more and 30 or less, 2 or more and 20 or less, or 2 or more and 10 or less. Examples of the alkenyl group include, but are not limited to, a vinyl group, 1-butenyl group, 1-pentenyl group, 1,3-butadienyl aryl group, styrenyl group, and styrylvinyl group.

In the present specification, examples of the arylamine group include a substituted or unsubstituted monoarylamine group, a substituted or unsubstituted diarylamine group, or a substituted or unsubstituted triarylamine group. The aryl group in the arylamine group may be a monocyclic aryl group, and may include a polycyclic aryl group or a monocyclic aryl group and a polycyclic aryl group at the same time.

Specific examples of the aryl amine group include phenylamine group, naphthylamine group, biphenylamine group, anthracenylamine group, 3-methyl-phenylamine group, 4-methyl-naphthylamine group, and 2-methyl-biphenylamine Group, 9-methyl-anthracenylamine group, diphenyl amine group, phenyl naphthylamine group, ditolyl amine group, phenyl tolyl amine group, carbazole and triphenyl amine group, but are not limited thereto.

In the present specification, examples of the heteroarylamine group include a substituted or unsubstituted monoheteroarylamine group, a substituted or unsubstituted diheteroarylamine group, or a substituted or unsubstituted triheteroarylamine group. The heteroaryl group in the heteroarylamine group may be a monocyclic heterocyclic group or a polycyclic heterocyclic group. The heteroarylamine group including two or more heterocyclic groups may include a monocyclic heterocyclic group, a polycyclic heterocyclic group, or a monocyclic heterocyclic group and a polycyclic heterocyclic group at the same time.

In the present specification, an arylheteroarylamine group means an amine group substituted with an aryl group and a heterocyclic group.

In the present specification, “adjacent group” may mean a substituent substituted on an atom directly connected to the atom where the corresponding substituent is substituted, another substituent substituted on an atom where the corresponding substituent is substituted, or a substituent that is three-dimensionally adjacent to the substituent. have. For example, in 1,2-dimethylbenzene, two methyl groups can be interpreted as "adjacent groups", and in 1,1-diethylcyclopentene, 2 The two ethyl groups can be interpreted as “adjacent groups” to each other.

Hereinafter, a tertiary amine derivative compound used in the organic material layer and/or the capping layer will be described.

The tertiary amine derivative compound according to an embodiment of the present invention is represented by the following formula (1).

[Formula 1]

In Formula 1,

Z ₁ is O or S,

n, p and q are each independently 0 or 1,

Ar ₁ and Ar ₂ are the same as each other, and a cyano group; An aryl group substituted with a cyano group; A substituted or unsubstituted dibenzofuran group; A substituted or unsubstituted dibenzothiophene group; A substituted or unsubstituted benzoxazole group; And a substituted or unsubstituted benzthiazole group; It is any one selected from among.

In an embodiment of the present invention, the tertiary amine derivative represented by Formula 1 may be any one selected from compounds represented by Formula 2 below, and the following compounds may be further substituted.

[Formula 2]

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 and 2.

1 is a schematic cross-sectional view of an organic light-emitting device according to an embodiment of the present invention. Referring to FIG. 1, in an organic light emitting diode according to an embodiment, a first electrode 110, a hole injection layer 210, a hole transport layer 215, a light emitting layer 220, and an electron are sequentially stacked on a substrate 100. A transport layer 230, an electron injection layer 235, a second electrode 120, and a capping layer 300 may be included.

The first electrode 110 and the second electrode 120 are disposed to face each other, and the organic material layer 200 may be disposed between the first electrode 110 and the second electrode 120. The organic material layer 200 may include a hole injection layer 210, a hole transport layer 215, a light emitting layer 220, an electron transport layer 230, and an electron injection layer 235.

Meanwhile, the capping layer 300 presented in the present invention is a functional layer deposited on the second electrode 120 and includes an organic material according to Formula 1 of the present invention.

In the organic light-emitting device of the exemplary embodiment illustrated in FIG. 1, the first electrode 110 has conductivity. The first electrode 110 may be formed of a metal alloy or a conductive compound. The first electrode 110 is generally an anode, but its function as an electrode is not limited.

The first electrode 110 may be formed on the substrate 100 by using an electrode material deposition method, an electron beam evaporation method, or a sputtering method. The material of the first electrode 110 may be selected from materials having a high work function to facilitate injection of holes into the organic light-emitting device.

The capping layer 300 proposed in the present invention is applied when the emission direction of the organic light-emitting device is front emission, and thus, the first electrode 110 uses a reflective electrode. These materials include Mg (magnesium), Al (aluminum), Al-Li (aluminum-lithium), Ca (calcium), Mg-In (magnesium-indium), and Mg-Ag (magnesium-silver), which are not oxides. It can also be made using the same metal. Recently, carbon substrate flexible electrode materials such as CNT (carbon nanotube) and graphene (graphene) may be used.

The organic material layer 200 may be formed of a plurality of layers. When the organic material layer 200 is a plurality of layers, the organic material layer 200 includes a hole transport region 210 to 215 disposed on the first electrode 110, a light emitting layer 220 disposed on the hole transport region, and the light emitting layer The electron transport regions 230 to 235 disposed on the 220 may be included.

The capping layer 300 according to an embodiment includes an organic compound represented by Formula 1 to be described later.

The hole transport regions 210 to 215 are provided on the first electrode 110. The hole transport regions 210 to 215 may include at least one of a hole injection layer 210, a hole transport layer 215, a hole buffer layer, and an electron blocking layer (EBL). It plays a role and generally has a thicker thickness than the electron transport region because the hole mobility is faster than the electron mobility.

The hole transport regions 210 to 215 may have a single layer made of a single material, a single layer made of a plurality of different materials, or a multilayer structure having a plurality of layers made of a plurality of different materials.

For example, the hole transport regions 210 to 215 may have a single layer structure of the hole injection layer 210 or the hole transport layer 215, or may have a single layer structure made of a hole injection material and a hole transport material. have. In addition, the hole transport regions 210 to 215 have a single-layer structure made of a plurality of different materials, or a hole injection layer 210/hole transport layer 215 sequentially stacked from the first electrode 110, Hole injection layer 210 / hole transport layer 215 / hole buffer layer, hole injection layer 210 / hole buffer layer, hole transport layer 215 / hole buffer layer, or hole injection layer 210 / hole transport layer 215 / electron Although it may have a structure of the blocking layer (EBL), the embodiment is not limited thereto.

Among the hole transport regions 210 to 215, the hole injection layer 210 may be formed on the anode by various methods such as a vacuum deposition method, a spin coating method, a cast method, and an LB method. When the hole injection layer 210 is formed by vacuum deposition, the deposition conditions are 100 to 500 depending on the compound used as the material of the hole injection layer 210 and the structure and thermal characteristics of the hole injection layer 210. The deposition rate at °C can be freely controlled by around 1 Å/s, and is not limited to specific conditions. In the case of forming the hole injection layer 210 by the spin coating method, the coating conditions are different depending on the characteristics between the compound used as the material of the hole injection layer 210 and the layers formed as the interface, but the coating speed and coating are used for even film formation. After the solvent is removed, heat treatment or the like is required.

The hole transport regions 210 to 215 are, for example, m-MTDATA, TDATA, 2-TNATA, NPB, β-NPB, TPD, Spiro-TPD, Spiro-NPB, methylated-NPB, TAPC, HMTPD, and TCTA. (4,4',4"-tris (N-carbazolyl) triphenylamine (4,4',4"-tris (Ncarbazolyl) triphenylamine)), Pani/DBSA (Polyaniline/Dodecylbenzenesulfonic acid: polyaniline/dodecylbenzene) Sulfonic acid), PEDOT/PSS(Poly(3,4-ethylenedioxythiophene)/Poly(4-styrene sulfonate):poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate)), Pani/CSA( Polyaniline/Camphor sulfonic acid: polyaniline/camphor sulfonic acid), PANI/PSS(Polyaniline)/Poly(4-styrenesulfonate):polyaniline)/poly(4-styrenesulfonate)), and the like.

The hole transport regions 210 to 215 may have a thickness of about 100 to about 10,000 Å, and the organic material layers of each hole transport region 210 to 215 are not limited to the same thickness. For example, if the thickness of the hole injection layer 210 is 50 Å, the thickness of the hole transport layer 215 may be 1000 Å, and the thickness of the electron blocking layer may be 500 Å. The thickness condition of the hole transport regions 210 to 215 may be set to a degree that satisfies efficiency and lifetime within a range in which an increase in the driving voltage of the organic light emitting device does not increase. The organic material layer 200 includes a hole injection layer 210, a hole transport layer 215, a functional layer having a hole injection function and a hole transport function at the same time, a buffer layer, an electron blocking layer, a light emitting layer 220, a hole blocking layer, an electron transport layer ( 230), an electron injection layer 235, and one or more layers selected from the group consisting of a functional layer having an electron transport function and an electron injection function at the same time.

The hole transport regions 210 to 215 may use doping to improve characteristics like the light emitting layer 220, and doping of a charge-generating material into the hole transport regions 210 to 215 will improve the electrical properties of the organic light emitting device. I can.

The charge-generating material is generally composed of a material having very low HOMO and LUMO. For example, the LUMO of the charge-generating material has a similar value to that of the hole transport layer 215 material. Due to such a low LUMO, the electrons of the LUMO are vacant, and holes are easily transferred to the adjacent hole transport layer 215 to improve electrical characteristics.

The charge-generating material may be, for example, a p-dopant. The p-dopant may be one of a quinone derivative, a metal oxide, and a cyano group-containing compound, but is not limited thereto. For example, non-limiting examples of the p-dopant include tetracyanoquinonedimethane (TCNQ) and 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinonedimethane Quinone derivatives such as phosphorus (F4-TCNQ) and the like; Metal oxides such as tungsten oxide and molybdenum oxide; Cyano group-containing compounds; And the like, but are not limited thereto.

In addition to the aforementioned materials, the hole transport regions 210 to 215 may further include a charge generating material to improve conductivity.

The charge generating material may be uniformly or non-uniformly dispersed in the hole transport regions 210 to 215. The charge generating material may be, for example, a p-dopant. The p-dopant may be one of a quinone derivative, a metal oxide, and a cyano group-containing compound, but is not limited thereto. For example, non-limiting examples of p-dopants include quinone derivatives such as TCNQ (Tetracyanoquinodimethane) and F4-TCNQ (2,3,5,6-tetracyanoquinodimethane), metal oxides such as tungsten oxide and molybdenum oxide, and the like. However, it is not limited thereto.

As described above, the hole transport regions 210 to 215 may further include at least one of a hole buffer layer and an electron blocking layer in addition to the hole injection layer 210 and the hole transport layer 215. The hole buffer layer may increase light emission efficiency by compensating for a resonance distance according to a wavelength of light emitted from the emission layer 220. As a material included in the hole buffer layer, a material capable of being included in the hole transport regions 210 to 215 may be used.

The electron blocking layer is a layer that serves to prevent injection of electrons from the electron transport regions 230 to 235 to the hole transport regions 210 to 215. The electron blocking layer may use a material having a high T1 value so as not only to block electrons moving to the hole transport region, but also to prevent the excitons formed in the light emitting layer 220 from diffusing into the hole transport regions 210 to 215. For example, in general, _{a host of the light emitting layer 220 having a high T 1} value may be used as a material for the electron blocking layer.

The emission layer 220 is provided on the hole transport regions 210 to 215. The emission layer 220 may have a thickness of, for example, about 100 Å to about 1000 Å or about 100 Å to about 300 Å. The emission layer 220 may have a single layer made of a single material, a single layer made of a plurality of different materials, or a multilayer structure having a plurality of layers made of a plurality of different materials.

The light emitting layer 220 is a region where holes and electrons meet to form excitons, and the material forming the light emitting layer 220 must have an appropriate energy band gap to exhibit high light emission characteristics and a desired light emission color, and generally play two roles as a host and a dopant. Eggplant is made of two materials, but is not limited thereto.

The host may include at least one of the following TPBi, TBADN, ADN (also referred to as "DNA"), CBP, CDBP, TCP, and mCP, and if the characteristics are appropriate, the material is not limited thereto.

The dopant of the emission layer 220 according to an embodiment may be an organic metal complex. The content of a general dopant may be selected from 0.01 to 20%, and is not limited thereto in some cases.

The electron transport regions 230 to 235 are provided on the emission layer 220. The electron transport regions 230 to 235 may include at least one of a hole blocking layer, an electron transport layer 230 and an electron injection layer 235, but is not limited thereto.

The electron transport regions 230 to 235 may have a single layer made of a single material, a single layer made of a plurality of different materials, or a multilayer structure having a plurality of layers made of a plurality of different materials.

For example, the electron transport regions 230 to 235 may have a single layer structure of the electron injection layer 235 or the electron transport layer 230, or may have a single layer structure made of an electron injection material and an electron transport material. have. In addition, the electron transport regions 230 to 235 have a single layer structure made of a plurality of different materials, or an electron transport layer 230 / electron injection layer 235 sequentially stacked from the light emitting layer 220, and hole blocking. The layer/electron transport layer 230/electron injection layer 235 may have a structure, but is not limited thereto. The thickness of the electron transport regions 230 to 235 may be, for example, about 1000 Å to about 1500 Å.

The electron transport regions 230 to 235 are various such as vacuum evaporation method, spin coating method, cast method, LB method (Langmuir-Blodgett), inkjet printing method, laser printing method, laser induced thermal imaging (LITI), etc. It can be formed using a method.

When the electron transport regions 230 to 235 include the electron transport layer 230, the electron transport region 230 may include an anthracene compound. However, the present invention is not limited thereto, and the electron transport region is, for example, Alq3(Tris(8-hydroxyquinolinato)aluminum),1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene,2 ,4,6-tris(3'-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine,2-(4-(N-phenylbenzoimidazolyl-1-ylphenyl)-9,10 -dinaphthylanthracene,TPBi(1,3,5-Tri(1-phenyl-1H-benzo[d]imidazol-2-yl)phenyl),BCP(2,9-Dimethyl-4,7-diphenyl-1,10- phenanthroline),Bphen(4,7-Diphenyl-1,10-phenanthroline),TAZ(3-(4-Biphenylyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole),NTAZ(4 -(Naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole),tBu-PBD(2-(4-Biphenylyl)-5-(4-tert-butylphenyl)-1, 3,4-oxadiazole),BAlq(Bis(2-methyl-8-quinolinolato-N1,O8)-(1,1'-Biphenyl-4-olato)aluminum), Bebq2(berylliumbis(benzoquinolin-10-olate), It may include ADN (9,10-di(naphthalene-2-yl)anthracene) and a mixture thereof.

Since the electron transport layer 230 is selected as a material having a fast electron mobility or a slow electron mobility according to the structure of the organic light emitting device, it is necessary to select a variety of materials, and in some cases, the following Liq or Li may be doped.

The electron transport layers 230 may have a thickness of about 100 Å to about 1000 Å, for example, about 150 Å to about 500 Å. When the thickness of the electron transport layers 230 satisfies the above-described range, satisfactory electron transport characteristics can be obtained without a substantial increase in driving voltage.

When the electron transport regions 230 to 235 include the electron injection layer 235, the electron transport regions 230 to 235 select a metal material that facilitates injection of electrons, and LiF, LiQ (Lithium quinolate), Lanthanum group metals such as Li ₂ O, BaO, NaCl, CsF, and Yb, or halogenated metals such as RbCl and RbI may be used, but are not limited thereto.

The electron injection layer 235 may also be formed of a material in which an electron transport material and an insulating organo metal salt are mixed. The organometallic salt may be a material having an energy band gap of approximately 4 eV or more. Specifically, for example, the organometallic salt may include metal acetate, metal benzoate, metal acetoacetate, metal acetylacetonate, or metal stearate. I can. The electron injection layers 235 may have a thickness of about 1 Å to about 100 Å, and about 3 Å to about 90 Å. When the thickness of the electron injection layers 235 satisfies the above-described range, satisfactory electron injection characteristics can be obtained without a substantial increase in driving voltage.

As mentioned above, the electron transport regions 230 to 235 may include a hole blocking layer. The hole blocking layer includes, for example, at least one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), and Balq It can be, but is not limited thereto.

The second electrode 120 is provided on the electron transport regions 230 to 235. The second electrode 120 may be a common electrode or a cathode. The second electrode 120 may be a transmissive electrode or a transflective electrode. Unlike the first electrode 110, the second electrode 120 may be used in combination with a metal having a relatively low work function, an electroconductive compound, an alloy, and the like.

The second electrode 120 is a transflective electrode or a reflective electrode. The second electrode 120 is Li (lithium), Mg (magnesium), Al (aluminum), Al-Li (aluminum-lithium), Ca (calcium), Mg-In (magnesium-indium), Mg-Ag (magnesium -Silver) or a compound or mixture containing them (eg, a mixture of Ag and Mg). Alternatively, a plurality of layer structures including a reflective film or a semi-transmissive film formed of the material and a transparent conductive film formed of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium tin zinc oxide (ITZO), etc. Can be

Although not shown, the second electrode 120 may be connected to the auxiliary electrode. When the second electrode 120 is connected to the auxiliary electrode, the resistance of the second electrode 120 may be reduced.

An electrode and an organic material layer are formed on the illustrated substrate 100, and in this case, a hard or soft material may be used as the material of the substrate 100. For example, the hard material is soda lime glass, alkali-free glass, aluminosilicate glass PC (polycarbonate), PES (polyethersulfone), COC (cyclic olefin copolymer), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), etc. can be used as the soft material. .

In the organic light emitting diode, as voltages are applied to the first electrode 110 and the second electrode 120, respectively, holes injected from the first electrode 110 pass through the hole transport regions 210 to 215 and the emission layer The electrons are moved to 220, and electrons injected from the second electrode 120 are transferred to the emission layer 220 through the electron transport regions 230 to 235. The electrons and holes recombine in the emission layer 220 to generate excitons, and the excitons fall from the excited state to the ground state to emit light.

The light path generated in the light emitting layer 220 may exhibit very different trends depending on the refractive indexes of organic and inorganic materials constituting the organic light emitting device. Light passing through the second electrode 120 may pass only light transmitted at an angle smaller than the critical angle of the second electrode 120. In addition, light that contacts the second electrode 120 greater than the critical angle is totally reflected or reflected, and thus cannot be emitted to the outside of the organic light-emitting device.

When the refractive index of the capping layer 300 is high, it contributes to the improvement of luminous efficiency by reducing such total reflection or reflection, and when it has an appropriate thickness, it contributes to high efficiency improvement and color purity by maximizing the micro-cavity phenomenon. .

The capping layer 300 is positioned on the outermost side of the organic light-emitting device, and does not affect the driving of the device at all and has a great influence on device characteristics. Therefore, the capping layer 300 is important from both viewpoints of improving device characteristics as well as an internal protection role of the organic light emitting device. Organic materials absorb light energy in a specific wavelength range, which depends on the energy band gap. If this energy band gap is adjusted for the purpose of absorbing the UV region that may affect organic materials inside the organic light emitting device, the capping layer 300 can be used for the purpose of protecting the organic light emitting device, including improving optical properties. have.

The organic light-emitting device according to the present specification may be a top emission type, a bottom emission type, or a double-sided emission type depending on the material used.

Hereinafter, examples will be described in detail in order to describe the present specification in detail. However, the embodiments according to the present specification may be modified in various other forms, and the scope of the present application is not construed as being limited to the embodiments described below. The embodiments of the present application are provided to more completely describe the present specification to those of ordinary skill in the art.

[Example]

Intermediate Synthesis example 1: Synthesis of intermediate (1)

4-bromodibenzo[b,d]furan (4-bromodibenzo[b,d]furan) 10.0 g (40.5 mmol), benzophenone imine 8.1 g (44.7 mmol), Pd (dba) ₂ 0.7 g A mixture of (1.2 mmol), 1.5 g (2.5 mmol) of BINAP, 11.7 g (121.7 mmol) of tert -butoxy sodium, and 200 mL of toluene was stirred at 110° C. all day. The reaction mixture was cooled to room temperature, passed through a pad of Celite, and then distilled under reduced pressure to remove the solvent. The obtained compound was dissolved in 100 mL of tetrahydrofuran, slowly acidified (pH<2) with a 4N hydrochloric acid solution, and stirred at 50° C. for 4 hours. After cooling to room temperature, tetrahydrofuran was removed by distillation under reduced pressure, and diethyl ether was added thereto, followed by stirring. The resulting solid was filtered under reduced pressure, and the filtered wet body was suspended in 200 mL of water, and the acidity was adjusted to 8 or more with a saturated sodium carbonate solution, followed by stirring for 1 hour. The resulting solid was filtered, washed with water, and dried under reduced pressure. The obtained compound was purified by column chromatography to obtain 5.0 g (yield: 67%) of a compound (intermediate (1)).

Intermediate Synthesis example 2: Synthesis of intermediate (3)

(Synthesis of intermediate (2))

4-bromo-1-iodobenzene 10.0 g (35.3 mmol), dibenzofuran-4-ylboronic acid 8.2 g (38.9 mmol), Pd ( PPh ₃ ) ₄ 0.2 g (1.1 mmol), 2M sodium carbonate solution 36.0 mL (72.0 mmol), a mixture of toluene 90 mL and ethanol 36 mL was stirred under reflux for 12 hours. The reaction mixture was cooled to room temperature, diluted with 100 mL of toluene, and washed with water. The organic layer was separated, dried over anhydrous magnesium sulfate, filtered, and concentrated to obtain 10.7 g (yield: 93%) of a solid compound (intermediate (2)).

(Synthesis of intermediate (3))

Intermediate (2) 60.0 g (185.7 mmol), Benzophenone imine 37.0 g (204.2 mmol), Pd (dba) ₂ 5.3 g (9.3 mmol), BINAP 11.5 g (18.5 mmol), tert -butoxy sodium A mixture of 44.6 g (464.1 mmol) and 600 mL of toluene was stirred under reflux for 12 hours. After cooling the reaction mixture to room temperature, it was dissolved in chloroform. After passing this solution through a pad of Celite, it was concentrated under reduced pressure. After dissolving the obtained compound in 500 mL of tetrahydrofuran, 80 mL of 6N hydrochloric acid was slowly added, followed by stirring at room temperature overnight. The resulting precipitate was filtered under reduced pressure and washed with chloroform. The filtered wet body was suspended in 600 mL of water, and the pH was adjusted to 8 or higher with saturated sodium carbonate solution, followed by extraction with chloroform and layer separation. The separated chloroform layer was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The concentrated residue was slurried with dichloromethane and normal hexane to obtain 28.0 g (yield: 58%) of a yellow solid compound (intermediate (3)).

Intermediate Synthesis example 3: Synthesis of intermediate (4)

1-(2-bromodibenzo[b,d]furan)(1-(2-bromodibenzo[b,d]furan)) 10.0 g (40.5 mmol), benzophenone imine 8.07 g (44.5 mmol) A mixture of 0.70 g (1.22 mmol) of Pd(dba) ₂ , 1.51 g (2.43 mmol) of BINAP, 7.78 g (81.0 mmol) of tert -butoxy sodium, and 100 mL of toluene was stirred under reflux for 12 hours. The reaction mixture was cooled to room temperature, diluted with 100 mL of toluene, and washed twice with 200 mL of water. The organic layer was separated, dried over anhydrous sodium sulfate, filtered and concentrated. After the concentrated residue was dissolved in 100 mL of tetrahydrofuran, 5 mL of 6N hydrochloric acid was slowly added, followed by stirring at 50° C. for 1 hour. After cooling to room temperature, the obtained solid was filtered under reduced pressure and washed with acetone. The filtered wet body was suspended in 200 mL of water, and the acidity was adjusted to 8 or more with a saturated sodium carbonate solution, followed by stirring for 1 hour. The resulting precipitate was filtered, washed with water, and dried under reduced pressure to obtain 4.09 g (yield: 55%) of the intermediate (4).

Intermediate Synthesis example 4: Synthesis of intermediate (5)

4-bromodibenzo[b,d]thiophene 10.0 g (38.0 mmol), benzophenone imine 6.9 g (38.0 mmol), Pd (dba) ₂ 1.1 A mixture of g (1.9 mmol), BINAP 2.4 g (3.8 mmol), tert -butoxy sodium 7.3 g (76.0 mmol), and 190 mL of toluene was stirred under reflux for 3 hours. After cooling the reaction mixture to room temperature, 190 mL of distilled water was added and extracted. 100 mL of 6 N HCl was added to the organic layer, stirred at room temperature for 3 hours, and then the resulting solid was filtered under reduced pressure. The filtered wet body was basified (pH>8) with saturated sodium carbonate solution and extracted with 190 mL of dichloromethane. The separated organic layer was dried over anhydrous sodium sulfate, filtered, concentrated, and purified by column chromatography to obtain 3.6 g (yield: 47.6%) of a pale orange solid compound (intermediate (5)).

Intermediate Synthesis example 5: Synthesis of intermediate (6)

2-bromodibenzo[b,d]thiophene 6.0 g (22.8 mmol), benzophenone imine 4.6 mL (27.4 mmol), Pd ₂ (dba) ₃ A mixture of 1.04 g (1.14 mmol), 1.42 g (2.28 mmol) of BINAP, 22.3 g (68.4 mmol) of cesium carbonate and 110 mL of toluene was stirred under reflux for 12 hours. The reaction mixture was cooled to room temperature, filtered through a pad of Celite, and the filtrate was concentrated under reduced pressure. The filtered wet body was dissolved in 70 mL of tetrahydrofuran, 30 mL of 6N hydrochloric acid was added, and the mixture was stirred for 1 hour. The mixture was basified (pH 7-8) with saturated sodium carbonate solution and extracted with dichloromethane. The separated organic layer was dried over anhydrous sodium sulfate, filtered, concentrated, and purified by column chromatography to obtain 2.72 g (yield: 59.9%) of a brown solid compound (intermediate (6)).

Intermediate Synthesis example 6: Synthesis of intermediate (8)

(Synthesis of intermediate (7))

4-bromo-1-iodobenzene 10.0 g (35.3 mmol), dibenzofuran-4-ylboronic acid 8.2 g (38.9 mmol), Pd ( PPh ₃ ) ₄ 0.2 g (1.1 mmol), 2M sodium carbonate solution 36.0 mL (72.0 mmol), a mixture of toluene 90 mL and ethanol 36 mL was stirred under reflux for 12 hours. The reaction mixture was cooled to room temperature, diluted with 100 mL of toluene, and washed with water. The organic layer was separated, dried over anhydrous magnesium sulfate, filtered, and concentrated to obtain 10.7 g (yield: 93%) of a solid compound (intermediate (7)).

(Synthesis of intermediate (8))

Intermediate (7) 60.0 g (185.7 mmol), Benzophenone imine 37.0 g (204.2 mmol), Pd (dba) ₂ 5.3 g (9.3 mmol), BINAP 11.5 g (18.5 mmol), tert -butoxy sodium A mixture of 44.6 g (464.1 mmol) and 600 mL of toluene was stirred under reflux for 12 hours. After cooling the reaction mixture to room temperature, it was dissolved in chloroform. After passing this solution through a pad of Celite, it was concentrated under reduced pressure. After dissolving the obtained compound in 500 mL of tetrahydrofuran, 80 mL of 6N hydrochloric acid was slowly added, followed by stirring at room temperature overnight. The resulting precipitate was filtered under reduced pressure and washed with chloroform. The filtered wet body was suspended in 600 mL of water, and the pH was adjusted to 8 or higher with saturated sodium carbonate solution, followed by extraction with chloroform and layer separation. The separated chloroform layer was dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The concentrated residue was slurried with dichloromethane and normal hexane to obtain 28.0 g (yield: 58%) of a yellow solid compound (intermediate (8)).

Intermediate Synthesis example 7: Synthesis of intermediate (9)

In a 1-neck 250 mL flask, intermediate (3) 4.6 g (17.7 mmol), 1-Bromo-4-iodobenzene 11.0 g (39.0 mmol), Pd (dba) ₂ 0.5 g (0.9 mmol), DPPF 1.0 g (1.8 mmol), NaOtBu 5.1 g (53.2 mmol), and 90 mL of toluene were added, followed by refluxing and stirring for 4 hours. After cooling at room temperature, impurities were removed through Celite filtration. After removing the solvent, it was dissolved in dichloromethane and purified by silica gel column chromatography (DCM:HEX). The obtained solid was filtered through a mixed solution (dichloromethane/acetone) to obtain 6.9 g (yield: 68.6%) of a white solid compound (intermediate (9)).

Intermediate Synthesis example 8: Synthesis of intermediate (10)

In a 1-neck 500 mL flask, intermediate (6) 4.0 g (20.1 mmol), 1-Bromo-4-iodobenzene 12.5 g (44.2 mmol), Pd (dba) ₂ 0.6 g (1.0 mmol), DPPF 1.1 g (2.0 mmol), NaOtBu 5.8 g (60.2 mmol), and toluene 100 mL were added, followed by refluxing and stirring for 4 hours. After cooling at room temperature, impurities were removed through Celite filtration. After removing the solvent, it was dissolved in dichloromethane and purified by silica gel column chromatography (DCM:HEX). The obtained solid was filtered with a mixed solution (acetone/methanol) to obtain 8.8 g (yield: 86.2%) of a yellow solid compound (intermediate (10)).

Intermediate Synthesis example 8: Synthesis of intermediate (11)

6-hydroxy-2-naphthonitrile (6-Hydroxy-2-naphthonitrile) 10.0 g (59.1 mmol) was dissolved in dichloromethane (DCM) 300 mL, and pyridine (Pyridine) 14.0 g (177.3 mmol) was added dropwise. The temperature was lowered to 0°C. Tf ₂ O 20.0 g (70.9 mmol) was slowly added dropwise, and the temperature was raised to room temperature, followed by reaction for 12 hours. After washing the reaction product with water (500 mL), the separated organic layer was dried over anhydrous sodium sulfate, filtered, concentrated, and purified by column chromatography (CHCl ₃ ) to form a yellow solid compound (intermediate (11)) 15.8 g (yield : 88.7%) was obtained.

Intermediate Synthesis example 9: Synthesis of intermediate (13)

(Synthesis of intermediate (12))

In a 1-neck 1000 mL flask, 1-bromo-4-iodobenzene 37.2 g (131.5 mmol), dibenzo[b,d]thiophen-4-ylboronic acid (dibenzo[b ,d]thiophen-4-ylboronic acid) 30.0 g (131.5 mmol), Pd (PPh ₃ ) ₄ 4.6 g (3.9 mmol) and toluene 400 mL were added and stirred, then ethanol 200 mL, K ₂ CO ₃ 27.3 g (197.3 mmol) )/200 mL of water was added, and the mixture was stirred for 8 hours under heating and refluxing. Upon completion of the reaction, the reaction mixture was cooled to room temperature, the solvent was removed, water was added, extracted with dichloromethane, the organic phase was dried over anhydrous MgSO ₄ , and purified by column chromatography (DCM) to form a slightly yellow solid compound (intermediate (12 )) 29.1 g (yield: 65.3%) was obtained.

(Synthesis of intermediate (13))

In a 1-neck 1000 mL flask, add 29.1 g (85.8 mmol) of the intermediate (12), 17.1 g (94.4 mmol) of benzophenone imine, 16.5 g (171.6 mmol) of NaOtBu, 500 mL of toluene, and stir, then Pd (dba). ₂ 1.5 g (2.6 mmol) and 3.2 g (5.2 mmol) of BINAP were added, and the mixture was stirred under heating and refluxing throughout the day. After the reaction was completed, the reaction was cooled to room temperature, the solvent was removed, water was added, extracted with dichloromethane, the organic phase was dried over anhydrous MgSO ₄ , passed through a pad covered with Celite with 1000 mL of chloroform, and then distilled under reduced pressure to remove the solvent. Removed. A slightly brownish liquid compound was mixed with 500 mL of tetrahydrofuran, stirred, and then adjusted to pH 2 or higher with 4N HCl, followed by stirring at 50° C. for 4 hours. Upon completion of the reaction, the solvent was blown off, acetone was added to the obtained solid, stirred for 30 minutes, and filtered to obtain a red solid. This solid was adjusted to pH 8 or higher with NaOH, stirred for 30 minutes, extracted with dichloromethane, removed the solvent, and purified by column chromatography (Hex:CHCl ₃ ) to form a slightly reddish solid compound (intermediate (13)) 12.6 g ( Yield: 53.4%) was obtained.

Various tertiary amine derivatives were synthesized as follows using the synthesized intermediate compound.

Example 1: Synthesis of compound 2-4 (LT19-35-308)

Intermediate (4) 2.8 g (15.4 mmol), 2-bromodibenzo[b,d]thiophene 8.9 g (33.9 mmol), Pd (dba) ₂ 1.8 g (3.1 mmol), tert -butoxysodium 7.4 g (77.1 mmol), tri- tert -butylphosphine 1.3 g (3.0 mmol, 50 wt% toluene solution), and a mixture of xylene 100 mL were stirred at 110° C. for 8 hours. The reaction mixture was cooled to room temperature, water was added, and then extracted twice with 300 mL of chloroform. The organic layer was dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained mixture was purified by column chromatography to obtain 4.9 g (yield: 58.1%) of compound 2-4 (LT19-35-308).

Example 2: Synthesis of compound 2-5 (LT19-30-224)

Intermediate (4) 1.5 g (8.2 mmol ), intermediate (2) 5.3 g (16.4 mmol ), Pd (dba) 2 0.2 g (0.4 mmol), tert - butoxy sodium 2.4 g (24.6 mmol), tree - tert - A mixture of 0.3 g (0.6 mmol, 50wt% toluene solution) of butylphosphine and 23 mL of toluene was stirred under reflux for 3 hours. After cooling the reaction mixture to room temperature, 115 mL of methanol was added. The resulting semi-solid precipitate was separated and purified by column chromatography to obtain 3.4 g (yield: 62.1%) of a yellow solid compound 2-5 (LT19-30-224).

Example 3: Synthesis of compound 2-9 (LT19-30-192)

Intermediate (1) 1.5 g (8.2 mmol), Intermediate (2) 5.3 g (16.4 mmol), Pd (dba) ₂ 0.2 g (1.2 mmol), tri- tert -butylphosphine 0.3 g (0.8 mmol, 50wt% toluene) Solution), tert -butoxy sodium 1.6 g (16.4 mmol), and a mixture of 82 mL of toluene were stirred under reflux for 8 hours. The reaction mixture was cooled to room temperature, washed with water, and the organic layer was separated, dried over anhydrous sodium sulfate, filtered and concentrated. The concentrated mixture was purified by column chromatography and recrystallized from dichloromethane and ethyl acetate to give 3.9 g (yield: 71.2%) of a white solid compound 2-9 (LT19-30-192).

Example 4: Synthesis of compound 2-13 (LT18-30-239)

Intermediate (4) 1.5 g(8.2 mmol), 2-(4-bromophenyl)benzo[d]oxazole(2-(4-bromophenyl)benzo[d]oxazole)5.3 g(19.3mmol), Pd(dba ) ₂ 483 mg (840.6 μmol), tri- tert -butylphosphine 680 mg (1.7 mmol, 50wt% toluene solution), tert -butoxy sodium 4.9 g (50.4 mmol) and a mixture of xylene 56 mL at 120°C The mixture was stirred for 12 hours. The reaction mixture was cooled to room temperature, diluted with chloroform, and washed with water. The organic layer was separated, dried over anhydrous sodium sulfate, filtered and concentrated. The obtained mixture was purified by column chromatography to obtain a yellow solid compound 2-13 (1.8 g (LT18-30-239) (yield: 38.5%)).

Example 5: Synthesis of compound 2-14 (LT19-30-305)

In a 250 mL one neck flask, 1.3 g (7.0 mmol) of intermediate (4), 5.1 g (14.7 mmol) of 2-(4-bromophenyl)benzothiazole (2-(4-bromophenyl)benzo[d]thiazole) and After adding 100 mL of xylene and stirring at 50 ℃, Pd(dba) ₂ 403.0 mg (0.7 mmol), Sodium tert -butoxide 2.0 g (21.0 mmol) and tri- tert -butylphospine (50wt% in Toluene) 567.2 mg ( 1.4 mmol) was added, followed by stirring at 125-130 °C all day. After the reaction was completed, the reaction mixture was cooled to room temperature, and the reaction product _{was passed through a Celite pad with CHCl 3} and distilled under reduced pressure to remove the solvent. The obtained compound was solidified with Hexane to obtain a yellow solid, _{dissolved by heating in 800 mL of CHCl 3, and} then charcoal was added and stirred for 30 minutes. _{After passing through a pad of Celite and SiO 2} using a hot mixed solvent (Hot CHCl ₃ :EA=20:1), the solvent was removed by distillation under reduced pressure. The obtained compound was _{purified by SiO 2} column chromatography (EA:CHCl ₃ :HEX=1:1:5). Slurry was performed with DCM and Hexane to obtain 3.1 g (yield: 73.5%) of compound 2-14 (LT19-35-305) as a yellow solid.

Example 6: Synthesis of compound 2-21 (LT19-30-312)

Intermediate (8) 1.7 g (6.5 mmol), intermediate (2) 4.6 g (14.4 mmol), tert -butoxy sodium 1.9 g (19.6 mmol), Pd (dba) ₂ 0.2 g (0.4 mmol), tri- tert -butylphosphine A mixture of 0.2 g (0.5 mmol, 50 wt% toluene solution) and 150 mL of xylene was stirred under reflux throughout the day. The reaction mixture was cooled to room temperature, diluted with 500 mL of chloroform, and filtered through a pad of Celite. After the filtrate was concentrated, the residue was purified by column chromatography to obtain 2.9 g (yield: 60.7%) of compound 2-21 (LT19-35-312) as a yellow solid.

Example 7: Synthesis of compound 2-27 (LT19-30-286)

Intermediate (3) 4.0 g (15.4 mmol), 4-bromobenzonitrile 8.4 g (46.3 mmol), Pd (dba) ₂ 1.8 g (3.1 mmol), tri- tert -butylphosphine 3.0 mL A mixture of (6.2 mmol, 50wt% toluene solution), tert -butoxysodium 5.9 g (61.7 mmol) and toluene 154 mL was stirred under reflux for 16 hours. The reaction mixture was cooled to room temperature, washed with water, and the organic layer was separated, dried over anhydrous sodium sulfate, filtered, and concentrated. The concentrated mixture was purified by column chromatography and recrystallized with ethyl acetate to obtain 1.3 g (yield: 18.3%) of an ivory solid compound 2-27 (LT19-30-286).

Example 8: Synthesis of compound 2-29 (LT19-30-259)

Intermediate (3) 4.0 g (15.4 mmol), 2-bromodibenzo[b,d]thiophene 8.9 g (33.9 mmol), Pd (dba) ₂ 1.8 g (3.1 mmol), tert -butoxysodium 7.4 g (77.1 mmol), tri- tert -butylphosphine 1.3 g (3.0 mmol, 50 wt% toluene solution), and a mixture of xylene 100 mL were stirred at 110° C. for 8 hours. The reaction mixture was cooled to room temperature, water was added, and then extracted twice with 300 mL of chloroform. The organic layer was dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained mixture was purified by column chromatography to obtain 1.7 g (yield: 17.7%) of compound 2-29 (LT19-30-259).

Example 9: Synthesis of compound 2-36 (LT19-30-278)

Intermediate (6) 2.5 g (12.5 mmol), 4-bromobenzonitrile 4.8 g (26.3 mmol), Pd (dba) ₂ 1.4 g (2.5 mmol), tert -butoxy sodium 6.0 g (62.7 mmol), tri- tert -butylphosphine 1.0 g (2.5 mmol, 50wt% toluene solution), and a mixture of xylene 100 mL were stirred at 110° C. for 8 hours. The reaction mixture was cooled to room temperature, water was added, and then extracted twice with 300 mL of chloroform. The organic layer was dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained compound was purified by column chromatography to obtain 1.4 g (yield: 27.9%) of compound 2-36 (LT19-30-278).

Example 10: Synthesis of compound 2-40 (LT19-30-218)

Intermediate (6) 1.3 g (6.5 mmol), Intermediate (2) 4.6 g (14.4 mmol), tert -butoxy sodium 1.9 g (19.6 mmol), Pd (dba) ₂ 0.2 g (0.4 mmol), tri- tert -butylphosphine A mixture of 0.2 g (0.5 mmol, 50 wt% toluene solution) and 150 mL of xylene was stirred under reflux throughout the day. The reaction mixture was cooled to room temperature, diluted with 500 mL of chloroform, and filtered through a pad of Celite. After the filtrate was concentrated, the residue was purified by column chromatography to obtain 2.7 g (yield: 60.7%) of compound 2-40 (LT19-30-218) as a yellow solid.

Example 11: Synthesis of compound 2-44 (LT19-30-199)

Intermediate (5) 2.0 g (10.0 mmol), intermediate (2) 6.5 g (20.1 mmol), Pd (dba) ₂ 0.6 g (1.0 mmol), tri- tert -butylphosphine 1.0 mL (2.0 mmol, 50wt% toluene) Solution), tert -butoxysodium 3.9 g (40.2 mmol), and a mixture of toluene 100 mL were stirred under reflux for 8 hours. The reaction mixture was cooled to room temperature, washed with water, and the organic layer was separated _{, dried over Na 2} SO ₄ , filtered and concentrated. The concentrated mixture was purified by column chromatography and recrystallized with dichloromethane and MeOH to obtain 1.5 g (yield: 21.9%) of a white solid compound 2-44 (LT19-30-199).

Example 12: Synthesis of compound 2-48 (LT18-30-263)

Intermediate (6) 1.6 g(8.0 mmol), 2-(4-bromophenyl)benzo[d]oxazole(2-(4-bromophenyl)benzo[d]oxazole) 5.5 g(20.1 mmol), Pd(dba ) ₂ 0.92 g (1.61 mmol), tri- tert -butylphosphine 1.3 g (3.2 mmol, 50wt% toluene solution), tert -butoxy sodium 3.1 g (32.1 mmol), and a mixture of xylene 54 mL were refluxed all day. Stirred. The reaction mixture was cooled to room temperature, filtered through a pad of Celite, and distilled under reduced pressure to remove the solvent. The obtained mixture was purified by column chromatography to obtain 3.1 g (yield: 66.2%) of compound 2-48 (LT18-30-263) as a brown solid.

Example 13: Synthesis of compound 2-87 (LT20-30-070)

In a 250 mL one neck flask, 2.8 g (15.3 mmol) of intermediate (4), 4'-bromo-[1.1'-biphenyl]-4-carbonitrile (4'-bromo-[1.1'-biphenyl]-4- carbonitrile) 8.7 g (33.6 mmol), NaO t Bu 4.4 g (45.8 mmol) and xylene 150 mL were added and _{stirred.Pd(dba) 2} 0.5 g (0.9 mmol), P( t -Bu) ₃ 0.3 mL (1.2 mmol) was added and stirred under heating to reflux throughout the day. When the reaction is complete, the mixture is cooled to room temperature, the solvent is blown off, and 500 mL of chloroform is passed through a pad of Celite, and the solvent is removed by distillation under reduced pressure. Purified by column chromatography (Hex:CHCl ₃ ) to give 2.5 g (yield: 30.4%) of compound 2-87 (LT20-30-070) as a yellow solid.

Example 14: Synthesis of compound 2-114 (LT20-30-068)

In a one neck 250 mL flask, intermediate (9) 4.7 g (8.3 mmol), 4-cyanophenylboronic acid 3.6 g (24.8 mmol), Pd (dba) ₂ 0.5 g (0.8 mmol), XPhos 0.8 g (1.7 mmol), 2M K ₃ PO ₄ 16 mL (33.0 mmol) and 1,4-dioxane 40 mL were added and stirred at 85° C. for 2 hours. After cooling at room temperature, the resulting solid was filtered and washed with ethanol. The solid was boiled in chloroform (200 mL) and purified through silica gel column chromatography (CHCl ₃ :HEX). The obtained solid was filtered with dichloromethane and washed with acetone to obtain 2.9 g (yield: 58.3%) of a yellow solid compound 2-114 (LT20-30-068).

Example 15: Synthesis of compound 2-117 (LT20-30-260)

In a 1-neck 250 mL flask, intermediate (3) 5.0 g (19.3 mmol), intermediate (11) 12.2 g (40.5 mmol), Pd (dba) ₂ 1.1 mg (1.9 mmol), 50% t-Bu ₃ P 1.6 g ( 3.9 mmol), NaOtBu 5.6 g (57.9 mmol) and Xylene 80 mL were added and mixed, and then reacted at 120° C. for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, water was added, extracted with chloroform, and the solvent was removed under reduced pressure. The obtained compound was purified by silica gel column chromatography (Hex:EA), dissolved in acetone, and solidified by slowly adding methanol dropwise thereto to obtain 1.5 g (yield: 13.8%) of compound 2-117 (LT20-30-260) as a yellow solid. Got it.

Example 16: Synthesis of compound 2-123 (LT20-30-051)

In a 1-neck 250 mL flask, intermediate (10) 4.6 g (9.0 mmol), 4-cyanophenylboronic acid 4.0 g (27.1 mmol), Pd (dba) ₂ 0.5 g (0.9 mmol), XPhos 0.9 g (1.8 mmol), 2M K ₃ PO ₄ 18 mL (36.1 mmol) and 1,4-dioxane 45 mL were added and stirred at 85° C. for 2 hours. After cooling at room temperature, the resulting solid was filtered and washed with ethanol. The solid was boiled in chloroform and purified through silica gel column chromatography (CHCl ₃ :HEX). The obtained solid was boiled with dichloromethane, cooled, filtered, and washed with acetone to obtain 3.4 g (yield: 68.7%) of a yellow solid compound 2-123 (LT20-30-051).

Example 17: Synthesis of compound 2-153 (LT20-35-365)

In a 1-neck 250 mL flask, intermediate (13) 5.0 g (18.2 mmol), intermediate (11) 11.5 g (38.1 mmol), Pd (dba) ₂ 1.0 mg (1.8 mmol), 50% t-Bu ₃ P 1.5 g ( 3.6 mmol), 5.2 g (54.5 mmol) of NaOtBu, and 80 mL of Xylene were added and mixed, and then reacted at 120° C. for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, water was added, extracted with chloroform, and the solvent was removed under reduced pressure. The obtained compound was purified by silica gel column chromatography (Hex:EA), dissolved in acetone, and then solidified while slowly adding methanol dropwise to obtain 1.1 g (yield: 10.5%) of a yellow solid compound 2-153 (LT20-35-365). Got it.

<Test Example>

For the compound of the present invention, J.A. Using WOOLLAM's Ellipsometer, the n (refractive index) and k (extinction coefficient) of the single film for optical property evaluation are measured.

Fabrication of single film for evaluation of optical properties:

For the optical property measurement of the compound, the glass substrate (0.7T) to Ethanol, DI Water, and then each washed for 10 minutes in Acetone, 2 × 10 ^- and an oxygen plasma treatment on the glass substrate for 2 minutes at ² Torr with 125 W 9 × ¹⁰ to deposit the compound on the glass substrate at a vacuum degree of ⁷ Torr at a rate of 1Å / sec 800Å it will be produced danmak.

Comparative Test Example:

REF01 was used as a compound in the preparation of a single film for evaluation of optical properties.

<Test Examples 1 to 17>

In the Comparative Test Example, a single membrane was manufactured in the same manner as in the Comparative Test Example, except that each compound shown in Table 1 was used instead of using REF01.

Table 1 shows the optical properties of the compounds according to the above Comparative Test Examples and Test Examples 1 to 17.

Optical properties are the refractive index constant at 450 nm and 620 nm wavelength and the absorption constant at 380 nm wavelength.

division compound n(450nm, 620nm) k(380nm) Comparative test example REF01 2.000, 1.846 0.193 Test Example 1 2-4
(LT19-35-308) 2.020, 1.884 0.253 Test Example 2 2-5
(LT19-30-224) 2.076, 1.922 0.557 Test Example 3 2-9
(LT19-30-192) 2.081,1.853 0.456 Test Example 4 2-13
(LT18-30-239) 2.241, 1.941 0.864 Test Example 5 2-14
(LT19-35-305) 2.282, 1.983 0.592 Test Example 6 2-21
(LT19-35-312) 2.123, 1.921 0.321 Test Example 7 2-27
(LT19-30-286) 2.111, 1.888 0.532 Test Example 8 2-29
(LT19-30-259) 2.041, 1.899 0.421 Test Example 9 2-36
(LT19-30-278) 2.123, 1.921 0.321 Test Example 10 2-40
(LT19-30-218) 2.086, 1.929 0.539 Test Example 11 2-44
(LT19-30-199) 2.020, 1.884 0.253 Test Example 12 2-48
(LT18-30-263) 2.283, 1.968 0.920 Test Example 13 2-87
(LT20-30-070) 2.253, 1.973 0.809 Test Example 14 2-114
(LT20-30-068) 2.302, 2.015 0.936 Test Example 15 2-117
(LT20-30-260) 2.294, 2.014 0.672 Test Example 16 2-123
(LT20-30-051) 2.265, 1.986 0.758 Test Example 17 2-153
(LT20-35-365) 2.284, 2.019 0.714

As can be seen from Table 1, n values in the blue region (450 nm) and red region (620 nm) of Comparative Test Example (REF01) were 2.000 and 1.846, respectively, whereas most of the compounds according to the present invention were As a result, it was confirmed to have a higher refractive index than Comparative Test Example compound (REF01) in the blue region, green region and red region. This satisfies the high refractive index value required to secure a high viewing angle in the blue region.

In addition, it was confirmed that the k value at 380 nm corresponding to the starting stage of the UV region was also high in most of the example compounds. This may contribute to substantially improving the lifespan of the organic electroluminescent device by effectively absorbing a high-energy external light source in the UV region to minimize damage to organic materials inside the organic light emitting device.

<Example>

Device fabrication

For device fabrication, ITO, a transparent electrode, was used as the anode layer, 2-TNATA was used as the hole injection layer, NPB was the hole transport layer, αβ-ADN was the host of the emission layer, Pyene-CN was the blue fluorescent dopant, Liq was the electron injection layer , Mg:Ag was used as a negative electrode. The structures of these compounds are shown in the following formula.

Comparative Example: ITO / 2-TNATA (60 nm) / NPB (20 nm) / αβ-ADN: 10% Pyrene-CN (30 nm) / Alq ₃ (30 nm) / Liq (2 nm) / Mg:Ag (1:9, 10 nm) / REF01 (60 nm)

Blue fluorescent organic light emitting device is ITO (180 nm) / 2-TNATA (60 nm) / NPB (20 nm) / αβ-ADN:Pyrene-CN 10% (30 nm) / Alq ₃ (30 nm) / Liq (2 nm) / Mg:Ag (1:9, 10 nm) / REF (60nm) was deposited in the order to fabricate a device. Before depositing the organic substance is applied to the ITO electrodes 2 × 10 ^- was for 2 minutes plasma treatment to 125W at ² Torr. Organics are 9 × 10 ^- were deposited at a vacuum degree of ⁷ Torr, Liq was 0.1 Å / sec, αβ-ADN is 0.18 Å / on the basis of sec Pyrene-CN was co-deposited with 0.02 Å / sec, all the remaining organics were 1 It was deposited at a rate of Å/sec. The capping layer material used in the experiment was selected as REF01. After the device was manufactured, the device was sealed in a glove box filled with nitrogen gas to prevent contact with air and moisture. After forming a partition wall with 3M's adhesive tape, barium oxide, a moisture absorbing agent that can remove moisture, was added and a glass plate was attached.

<Examples 1 to 17>

In the comparative example, a device was manufactured in the same manner as in the comparative example, except that each compound shown in Table 2 was used instead of using REF01.

Table 2 shows the electroluminescence characteristics of the organic light emitting devices prepared in Comparative Examples and Examples 1 to 17.

division compound Driving voltage [V] Efficiency [cd/A] life span(%) Comparative Example REF01 4.50 5.10 88.92 Example 1 2-4
(LT19-35-308) 4.42 6.11 97.54 Example 2 2-5
(LT19-30-224) 4.47 6.52 98.13 Example 3 2-9
(LT19-30-192) 4.45 6.13 97.45 Example 4 2-13
(LT18-30-239) 4.38 6.23 97.40 Example 5 2-14
(LT19-35-305) 4.40 6.10 97.32 Example 6 2-21
(LT19-35-312) 4.41 6.23 97.55 Example 7 2-27
(LT19-30-286) 4.42 6.00 98.00 Example 8 2-29
(LT19-30-259) 4.49 5.99 95.61 Example 9 2-36
(LT19-30-278) 4.40 6.22 98.11 Example 10 2-40
(LT19-30-218) 4.42 6.11 97.54 Example 11 2-44
(LT19-30-199) 4.40 6.25 97.42 Example 12 2-48
(LT18-30-263) 4.41 6.23 97.55 Example 13 2-87
(LT20-30-070) 4.45 6.12 97.35 Example 14 2-114
(LT20-30-068) 4.45 6.21 97.91 Example 15 2-117
(LT20-30-260) 4.43 6.11 97.56 Example 16 2-123
(LT20-30-051) 4.45 6.22 97.00 Example 17 2-153
(LT20-35-365) 4.44 6.15 97.49

From the results of Table 2 above, the specific tertiary amine derivative compound according to the present invention can be used as a material for the capping layer of organic electronic devices including organic light emitting devices, and organic electronic devices including organic light emitting devices using the same can be used in terms of efficiency, It can be seen that it exhibits excellent characteristics in terms of driving voltage and stability. In particular, the compound according to the present invention exhibited high efficiency characteristics due to excellent micro-cavity capability.

The compound of Formula 1 has surprisingly desirable properties for use as a capping layer in OLED.

The compounds of the present invention can be applied to industrial organic electronic device products due to these properties.

However, the above synthesis example is an example, and the reaction conditions may be changed as necessary. In addition, the compound according to an embodiment of the present invention may be synthesized to have various substituents using methods and materials known in the art. By introducing various substituents to the core structure represented by Chemical Formula 1, it may have properties suitable for use in an organic electroluminescent device.

100: substrate, 110: first electrode, 120: second electrode, 200: organic material layer, 210: hole injection layer, 215: hole transport layer, 220: light emitting layer, 230: electron transport layer, 235: electron injection layer, 300: capping layer

Claims (3)

A tertiary amine derivative for a capping layer of an organic electroluminescent device represented by the following formula (1).
[Formula 1]

Z ₁ is O or S,
n, p and q are each independently 0 or 1,
Ar ₁ and Ar ₂ are the same as each other, and a cyano group; An aryl group substituted with a cyano group; A substituted or unsubstituted dibenzofuran group; A substituted or unsubstituted dibenzothiophene group; A substituted or unsubstituted benzoxazole group; And a substituted or unsubstituted benzthiazole group; It is any one selected from among. The method of claim 1,
Formula 1 is a tertiary amine derivative for a capping layer of an organic electroluminescent device selected from compounds represented by Formula 2 below.
[Formula 2]

A first electrode;
An organic material layer formed of a plurality of organic material layers disposed on the first electrode;
A second electrode disposed on the organic material layer; And
Including; a capping layer disposed on the second electrode,
The capping layer is an organic electroluminescent device comprising the tertiary amine derivative according to any one of claims 1 to 2.

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