KR102251474B1 - Novel organic electroluminescent compounds and organic electroluminescent device comprising the same - Google Patents

Abstract

The present invention relates to a novel organic electroluminescent compound and an organic electroluminescent device including the same, and the organic electroluminescent compound of the present invention can be used in a light emitting layer, has excellent luminous efficiency, and has a long driving life, current efficiency and power efficiency. This improved organic electroluminescent device can be manufactured.

Description

A novel organic electroluminescent compound and an organic electroluminescent device including the same TECHNICAL FIELD [NOVEL ORGANIC ELECTROLUMINESCENT DEVICE COMPRISING THE SAME}

The present invention relates to a novel organic electroluminescent compound and an organic electroluminescent device including the same.

An electroluminescence device (EL device) is a self-luminous display device and has an advantage in that it has a wide viewing angle, excellent contrast, and a high response speed. In 1987, Eastman Kodak Co., Ltd. first developed an organic EL device using a low-molecular aromatic diamine and an aluminum complex as a material for forming a light emitting layer [see Appl. Phys. Lett. 51, 913, 987].

An organic EL device usually has a structure including an anode and a cathode, and an organic material layer therebetween, and light emission occurs by recombination of holes and electrons injected from the anode and the cathode. The organic material layer of the organic EL device may be composed of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, etc., and the material used for the organic material layer is a hole injection material, a hole transport material, a light emitting material, an electron transport material, It is divided into electron injection materials.

The light-emitting material of an organic EL device is the most important factor in determining the light-emitting efficiency of the device. The light-emitting material must have high quantum efficiency and high mobility of electrons and holes, and the formed light-emitting material layer must be uniform and stable. These light-emitting materials are classified into blue, green, or red light-emitting materials according to the light-emitting color, and there are additionally yellow or orange light-emitting materials. Further, the light-emitting material is classified into a fluorescent light-emitting material (singlet excited state) and a phosphorescent light-emitting material (triplet excited state) according to the excited state. Initially, organic EL devices mainly used fluorescent materials, but phosphorescent materials containing phosphorus as the main component have more than four times the efficiency of converting electricity into light (luminescence efficiency) compared to fluorescent materials and can reduce power consumption, so they have a relatively long lifespan. In view of the prolonged effect, research on the development of phosphorescent materials has been widely conducted.

Until now, iridium (III) complex series are widely known as phosphorescent materials, and (acac)Ir(btp) ₂ (bis(2-(2'-benzothienyl)-pyridine) for each red, green, and blue light emission. Naito-N,C-3') iridium (acetylacetonate)), Ir (ppy) ₃ (tris (2-phenylpyridine) iridium) and Firpic (bis (4,6-difluorophenylpyridinato) Materials such as -N,C2) picol lineatoiridium) are known.

The light-emitting material may be used by mixing a host and a dopant to improve color purity, luminous efficiency, and stability. When using such a dopant/host material system, the host material has a great influence on the efficiency and performance of the light emitting device, so the selection is important. In the prior art, as a host material for phosphorescence, 4,4'-N,N'-dicarbazole-biphenyl (CBP) was most widely known. In recent years, Bathocuproine (BCP) and aluminum (III) bis(2-methyl-8-quinolinate) (4-phenylphenolate), which were used as materials for hole blocking layers by Japanese pioneers, etc. Balq) has been used as a host material to develop high-performance organic EL devices.

However, the existing host materials for phosphorescence have advantages in terms of light emission characteristics, but have the following disadvantages: (1) The glass transition temperature is low and the thermal stability is low, so that when the material undergoes a high-temperature evaporation process under vacuum, the material is Changes. (2) In an organic EL device, power efficiency = [(π/voltage) × current efficiency], so power efficiency is inversely proportional to voltage. An organic EL device using a phosphorescent host material has a higher current efficiency (cd/A) than an organic EL device using a fluorescent host material, but has a significantly higher driving voltage, so there is no significant advantage in terms of power efficiency (lm/w). (3) When used in an organic EL device, the operating life is not satisfactory, and the luminous efficiency is still required to be improved.

Meanwhile, copper phthalocyanine (CuPc), 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB), N,N'- Diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (TPD), 4,4',4"-tris(3-methylphenylphenyl) Although amino) triphenylamine (MTDATA) has been used, there is a problem in that the quantum efficiency and lifetime of the organic EL device are deteriorated when such a material is used, because when the organic EL device is driven at a high current, the anode and the anode are used. This is because thermal stress occurs between the hole injection layers, and the life of the device is rapidly reduced due to such thermal stress. The hole-electron charge balance is broken, resulting in a lower quantum efficiency (cd/A).

Therefore, in order to implement excellent characteristics of the organic EL device, materials constituting the organic material layer in the device, particularly, a host or dopant constituting a light emitting material must be appropriately selected. Meanwhile, Korean Patent Publication No. 1219492 discloses an organic electroluminescent compound containing a fused heterocycle having a specific structure, and the inventors of the present application synthesize the compound disclosed in the registered patent publication through actual experiments to determine the characteristics of the light emitting device. By testing, it was confirmed that the compound device performance was excellent. Accordingly, as a result of researching to find an organic electroluminescent compound capable of providing a light emitting device with better performance than the compound described in the above registered patent publication, the compound of the present invention has high luminous efficiency and provides excellent device performance, and has a molecular weight. It has been found that the reduction can increase thermal stability by lowering the deposition temperature and improve the synthesis method as well.

Korean Patent Publication No. 1219492 (filing date: December 11, 2009, notification date: January 28, 2013)

Accordingly, an object of the present invention is to firstly provide an organic electroluminescent compound having high luminous efficiency, and secondly, an organic electroluminescent compound including the organic electroluminescent compound, which has a long driving life, and has improved power efficiency and current efficiency. It is to provide the device.

As a result of intensive research in order to solve the above technical problem, the present inventors have completed the present invention by discovering that the compound represented by the following formula (1) achieves the above-described object.

[Formula 1]

In Formula 1,

L ₁ is a single bond, a substituted or unsubstituted (3-30 membered) heteroarylene, a substituted or unsubstituted (C6-C30)arylene, or (C1-C30) alkylene;

X ₁ is NR ₅ , -CR ₆ R ₇ , O or S, provided that when Y ₁ is -N-, X ₁ is not S;

X ₂ to X ₅ are each independently -CR ₈ -or -N-;

Y ₁ and Y ₂ are each independently -CR ₉ -or -N- _{, when Y 1} is -N-, Y ₂ is -CR ₉ -, and when Y ₁ is -CR ₉ -, Y ₂ is -N-;

R ₁ to R ₄ are each independently hydrogen, deuterium, halogen, cyano, carboxyl, nitro, hydroxy, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C3-C30)cycloalkyl , Substituted or unsubstituted (C3-C30)cycloalkenyl, substituted or unsubstituted (3-7 member) heterocycloalkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (3- 30 membered) heteroaryl, substituted or unsubstituted (C6-C30) arylamine, -NR ₁₀ R ₁₁ or -SiR ₁₂ R ₁₃ R ₁₄ ;

R ₁ , R ₂ and R ₃ together with adjacent substituents may form a (C3-C30) monocyclic or polycyclic alicyclic or aromatic ring;

R ₅ to R ₉ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (3-30 membered) Heteroaryl, substituted or unsubstituted (C3-C30)cycloalkyl, substituted or unsubstituted (5-7 membered) heterocycloalkyl, substituted or unsubstituted (C6-C30)ar(C1-C30)alkyl,- NR ₁₀ R ₁₁ , SiR ₁₂ R ₁₃ R ₁₄ , cyano, nitro or hydroxy;

R ₁₀ and R ₁₁ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, or substituted or unsubstituted (3-30 membered ) Heteroaryl;

R ₁₂ to R ₁₄ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (3-30 membered) Heteroaryl, substituted or unsubstituted (5-7 membered) heterocycloalkyl, or substituted or unsubstituted (C3-C30) cycloalkyl, or substituted or unsubstituted (3-30 membered) monocyclic with an adjacent substituent Or it may form a polycyclic alicyclic or aromatic ring;

The alicyclic or aromatic ring carbon atom may be replaced by one or more heteroatoms selected from nitrogen, oxygen and sulfur;

The heteroaryl(ene) and heterocycloalkyl contain one or more heteroatoms selected from B, N, O, S, P(=O), Si and P;

a, b, c and d are each independently an integer of 1 to 4, and when an integer of 2 or more, each of R ₁ , R ₂ , R ₃ and R ₄ may be the same or different.

The organic electroluminescent compound according to the present invention has excellent luminous efficiency and excellent material life characteristics, and an organic electroluminescent device including such a compound has a long driving life and very good current efficiency and power efficiency.

Hereinafter, the present invention will be described in more detail, but this is for illustrative purposes and should not be construed as limiting the scope of the present invention.

The present invention relates to an organic electroluminescent compound represented by Formula 1, an organic electroluminescent material including the organic electroluminescent compound, and an organic electroluminescent device including the material.

"(C1-C30)alkyl (ene)" as described in the present invention means a straight-chain or branched-chain alkyl (ene) having 1 to 30 carbon atoms, where it is preferably 1 to 20 carbon atoms, and 1 to It is more preferable to have 10. Specific examples of the alkyl include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl. As used herein, "(C2-C30)alkenyl" refers to a straight-chain or branched alkenyl having 2 to 30 carbon atoms, wherein the carbon number is preferably 2 to 20, and more preferably 2 to 10. Specific examples of the alkenyl include vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, and 2-methylbut-2-enyl. As used herein, "(C2-C30)alkynyl" refers to a straight-chain or branched-chain alkynyl having 2 to 30 carbon atoms, where it is preferably 2 to 20 carbon atoms, and more preferably 2 to 10 carbon atoms. Examples of the alkynyl include ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-methylpent-2-ynyl, and the like. As used herein, "(C3-C30)cycloalkyl" refers to a monocyclic or polycyclic hydrocarbon having 3 to 30 carbon atoms, and preferably 3 to 20 carbon atoms, and more preferably 3 to 7 carbon atoms. Examples of the cycloalkyl include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and the like. As used herein, "(3-7 member) heterocycloalkyl" has 3 to 7, preferably 5 to 7 ring skeleton atoms, and consists of B, N, O, S, P(=O), Si and P It means a cycloalkyl containing at least one heteroatom selected from the group, preferably at least one heteroatom selected from O, S and N, and, for example, tetrahydrofuran, pyrrolidine, thiolane, tetrahydropyran, etc. There is this. As used herein, "(C6-C30)aryl (ene)" refers to a monocyclic or fused cyclic radical derived from an aromatic hydrocarbon having 6 to 30 carbon atoms, wherein the cyclic skeletal carbon number is preferably 6 to 20, and 6 It is more preferably 15 to 15. Examples of the aryl include phenyl, biphenyl, terphenyl, naphthyl, fluorenyl, phenanthrenyl, anthracenyl, indenyl, triphenylenyl, pyrenyl, tetracenyl, perylenyl, chrysenyl, naphthacenyl And fluoranthenyl. As used herein, "(3-30 membered) heteroaryl (ene)" has 3 to 30 ring skeleton atoms, and at least one hetero selected from the group consisting of B, N, O, S, P(=O), Si and P It means an aryl group containing an atom. Here, the number of ring skeleton atoms is preferably 3 to 20, and more preferably 3 to 15. The number of heteroatoms is preferably 1 to 4, and may be a single ring system or a fused ring system condensed with one or more benzene rings, and may be partially saturated. In addition, the heteroaryl (ene) herein also includes a form in which one or more heteroaryl groups or aryl groups are connected to a heteroaryl group by a single bond. Examples of the heteroaryl include furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl , Triazolyl, tetrazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, and other single ring heteroaryl, benzofuranyl, benzothiophenyl, isobenzofuranyl, dibenzofuranyl, di Benzothiophenyl, benzoimidazolyl, benzothiazolyl, benzoisothiazolyl, benzoisoxazolyl, benzoxazolyl, isoindolyl, indolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, sine Fused cyclic heteroaryls such as nolinyl, quinazolinyl, quinoxalinyl, carbazolyl, phenoxazyl, phenanthridinyl, and benzodioxolyl. “Halogen” as used herein includes F, Cl, Br and I atoms.

In addition, in the description of "substituted or unsubstituted" described in the present invention, "substituted" means that a hydrogen atom is replaced by another atom or another functional group (ie, a substituent) in a certain functional group. Substituted (C1-C30)alkyl (ene), substituted (C3-C30)cycloalkyl, substituted (C3-C30)cycloalkenyl, substituted (3-7 membered) in _{L 1} and R ₁ to R ₁₄ of the formulas of the present invention ) Heterocycloalkyl, substituted (C6-C30) aryl (ene), substituted (3-30 membered) heteroaryl (ene) and substituted (3-30 membered) monocyclic or polycyclic alicyclic or aromatic ring substituents, respectively Independently, deuterium, halogen, cyano, carboxyl, nitro, hydroxy, (C1-C30)alkyl, halo(C1-C30)alkyl, (C2-C30)alkenyl, (C2-C30)alkynyl, ( C1-C30)alkoxy, (C1-C30)alkylthio, (C3-C30)cycloalkyl, (C3-C30)cycloalkenyl, (3-7 member)heterocycloalkyl, (C6-C30)aryloxy, ( C6-C30) arylthio, (C6-C30) aryl substituted or unsubstituted (3-30 membered) heteroaryl, (3-30 membered) heteroaryl substituted or unsubstituted (C6-C30) aryl, tri (C1-C30)alkylsilyl, tri(C6-C30)arylsilyl, di(C1-C30)alkyl(C6-C30)arylsilyl, (C1-C30)alkyldi(C6-C30)arylsilyl, amino, mono Or di(C1-C30)alkylamino, mono or di(C6-C30)arylamino, (C1-C30)alkyl(C6-C30)arylamino, (C1-C30)alkylcarbonyl, (C1-C30)alkoxy Carbonyl, (C6-C30)arylcarbonyl, di(C6-C30)arylboronyl, di(C1-C30)alkylboronyl, (C1-C30)alkyl(C6-C30)arylboronyl, One or more selected from the group consisting of (C6-C30)ar(C1-C30)alkyl and (C1-C30)alkyl(C6-C30)aryl.

The compound represented by Formula 1 may be represented by the following Formula 2.

[Formula 2]

In Chemical Formula 2,

Y ₂ is -CR ₉ -, _{and the definitions of L 1} , X ₁ to X ₅ , R ₁ to R ₁₄ , a, b, c and d are the same as those in Formula 1.

The compound represented by Formula 1 may be represented by the following Formula 3.

[Formula 3]

In Chemical Formula 3,

Y ₁ is -CR ₉ -, and L ₁ , X ₁ to X ₅ , R ₁ to R ₁₄ , The definitions of a, b, c and d are the same as those in Chemical Formula 1.

The compound represented by Formula 1 may be represented by the following Formula 4.

[Formula 4]

In Chemical Formula 4,

Y ₁ and Y ₂ are -CR ₉ -, X ₂ , X ₃ and X ₄ are -CR ₈ - _{, and the definitions of L 1} , X ₁ , R ₁ to R ₁₄ , a, b, c, and d are It is the same as the definition in Formula 1.

In Formulas 1 to 4, preferably, L ₁ is a single bond or a substituted or unsubstituted (C6-C30) arylene, and R ₁ to R ₄ are each independently hydrogen, cyano, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (3-30 membered)heteroaryl or -NR ₁₀ R ₁₁ ; R ₅ to R ₉ are each independently hydrogen or a substituted or unsubstituted (C6-C30)aryl, and R ₁₀ and R ₁₁ are each independently a substituted or unsubstituted (C6-C30)aryl.

The compound represented by Formula 1 is selected from the following compounds.

The organic electroluminescent compound according to the present invention can be prepared by a synthetic method known to those skilled in the art, for example, can be prepared according to the following scheme.

In a further aspect, the present invention provides an organic electroluminescent material comprising the organic electroluminescent compound of Formula 1 and an organic electroluminescent device comprising the material. The material may be formed of the organic electroluminescent compound of the present invention alone, and may further include materials included in the organic electroluminescent material. The organic electroluminescent device according to the present invention comprises: a first electrode; A second electrode; And at least one organic material layer interposed between the first electrode and the second electrode, wherein the organic material layer includes at least one compound of Formula 1 above.

One of the first electrode and the second electrode may be an anode and the other may be a cathode. The organic material layer includes an emission layer, and may further include at least one layer selected from a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, an interlayer, and a hole blocking layer.

The organic electroluminescent compound of Formula 1 of the present invention may be included in the emission layer as a host material. Preferably, the emission layer may include one or more dopants, and if necessary, may further include a compound other than the organic electroluminescent compound of Formula 1 of the present invention as a second host material.

The present invention provides a material for manufacturing an organic electroluminescent device in a further aspect. The material includes a first host material and a second host material, and the first host material includes the organic electroluminescent compound of the present invention. At this time, the weight ratio of the first host material and the second host material is in the range of 1:99 to 99:1.

As the second host material, any known phosphorescent host may be used, and preferably, a phosphorescent host represented by the following Chemical Formulas 5 to 9 may be selected and used.

[Formula 5]

H-(Cz-L ₄ ) _h -M

[Formula 6]

H-(Cz) _i -L ₄ -M

[Formula 7]

[Formula 8]

[Formula 9]

In Formulas 5 to 9,

Cz is the following structure,

X is -O- or -S-;

R ₂₁ to R ₂₄ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (5-30 membered) heteroaryl, or Is R ₂₅ R ₂₆ R ₂₇ Si-; It is connected with an adjacent substituent to form a (5-30 membered) monocyclic or polycyclic alicyclic or aromatic ring, wherein the carbon atom of the formed alicyclic or aromatic ring is at least one selected from nitrogen, oxygen, and sulfur. May be replaced by a heteroatom;

R ₂₅ to R ₂₇ are each independently substituted or unsubstituted (C1-C30)alkyl, or substituted or unsubstituted (C6-C30)aryl;

L ₄ is a single bond, a substituted or unsubstituted (C6-C30)arylene, or a substituted or unsubstituted (5-30 membered) heteroarylene;

M is a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (5-30 membered) heteroaryl;

Y ₁ and Y ₂ are each independently -O-, -S-, -N(R ₃₁ )-, or -C(R ₃₂ )(R ₃₃ )-, and Y ₁ and Y ₂ are not present at the same time;

R ₃₁ to R ₃₃ are each independently a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (5-30 membered) heteroaryl; It is connected with an adjacent substituent to form a (5-30 membered) monocyclic or polycyclic alicyclic or aromatic ring, wherein the carbon atom of the formed alicyclic or aromatic ring is at least one selected from nitrogen, oxygen, and sulfur. May be replaced by a heteroatom; R ₃₂ and R ₃₃ may be the same or different;

h and i are each independently an integer of 1 to 3;

j, k, l and m are each independently an integer of 0 to 4;

When h, i, j, k, l or m is an integer of 2 or more, each (Cz-L ₄ ), each (Cz), each R ₂₁ , each R ₂₂ , each R ₂₃ or each R ₂₄ May be the same or different.

Specifically, preferred examples of the second host material are as follows.

[Here, TPS is triphenylsilyl]

As the dopant, at least one phosphorescent dopant is preferable. The phosphorescent dopant material applied to the organic electroluminescent device of the present invention is not particularly limited, but a complex compound of metal atoms selected from iridium (Ir), osmium (Os), copper (Cu), and platinum (Pt) is preferred. And, an ortho-metallized complex compound of a metal atom selected from iridium (Ir), osmium (Os), copper (Cu) and platinum (Pt) is more preferable, and an ortho-metallized iridium complex compound is even more preferable.

Compounds represented by the following Chemical Formulas 10 to 12 may be used as the dopant included in the organic electroluminescent device of the present invention.

[Formula 10] [Formula 11] [Formula 12]

In Formulas 10 to 12,

L is selected from the following structures;

R ₁₀₀ is hydrogen, substituted or unsubstituted (C1-C30)alkyl, or substituted or unsubstituted (C3-C30)cycloalkyl;

R ₁₀₁ to R ₁₀₉ and R ₁₁₁ to R ₁₂₃ are each independently hydrogen, deuterium, halogen, halogen-substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C3-C30)cycloalkyl, cyano , Or a substituted or unsubstituted (C1-C30)alkoxy; R ₁₂₀ to R ₁₂₃ may have adjacent substituents linked to each other to form a fused ring, for example, quinoline may be formed;

R ₁₂₄ to R ₁₂₇ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C1-C30)alkyl, or substituted or unsubstituted (C6-C30)aryl; When R ₁₂₄ to R ₁₂₇ are an aryl group, adjacent groups may be linked to each other to form a fused ring, for example, fluorene may be formed;

R ₂₀₁ to R ₂₁₁ are each independently hydrogen, deuterium, halogen, or halogen-substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C3-C30)cycloalkyl, or (C6-C30)aryl. ego;

f and g are each independently an integer of 1 to 3; When f or g is an integer of 2 or more, each R ₁₀₀ may be the same as or different from each other;

n is an integer of 1 to 3.

Specific examples of the phosphorescent dopant material are as follows.

The organic electroluminescent device of the present invention may include the organic electroluminescent compound of Formula 1 in the organic material layer, and at the same time include at least one compound selected from the group consisting of an arylamine-based compound and a styrylarylamine-based compound.

In addition, in the organic electroluminescent device of the present invention, in the organic material layer, in addition to the organic electroluminescent compound of Formula 1, a group 1, a group 2, a period 4 transition metal, a period 5 transition metal, a lanthanum metal, and an organic metal of the d-transition element One or more metals selected from the group consisting of, or one or more complex compounds containing such metals may be further included.

In addition, the organic electroluminescent device of the present invention may emit white light by further including at least one light-emitting layer including a blue, red, or green light-emitting compound known in the art in addition to the organic electroluminescent compound of the present invention. Further, if necessary, a yellow or orange light emitting layer may be further included.

In the organic electroluminescent device of the present invention, on at least one inner surface of the pair of electrodes, at least one layer selected from a chalcogenide layer, a metal halide layer, and a metal oxide layer (hereinafter referred to as "surface layer" It is preferable to place). Specifically, it is preferable to provide a silicon and aluminum chalcogenide (including oxide) layer on the surface of the anode on the side of the light emitting medium layer, and a metal halide layer or a metal oxide layer on the surface of the cathode on the side of the light emitting medium layer. Stabilization of driving of the organic electroluminescent device can be obtained by the surface layer. Preferred examples of the chalcogenide include SiO _X (1≤X≤2), AlO _X (1≤X≤1.5), SiON or SiAlON, and preferred examples of the metal halide include LiF, MgF ₂ , CaF ₂ , fluoride Rare earth metals, and the like, and preferred examples of metal oxides include Cs ₂ O, Li ₂ O, MgO, SrO, BaO, CaO, and the like.

In addition, in the organic electroluminescent device of the present invention, it is also preferable to arrange a mixed region of an electron transfer compound and a reducing dopant, or a mixed region of a hole transport compound and an oxidizing dopant on at least one surface of the pair of electrodes. . In this way, since the electron transfer compound is reduced to an anion, it becomes easy to inject and transfer electrons from the mixed region to the light emitting medium. Further, since the hole transport compound is oxidized to become a cation, it becomes easy to inject and transfer holes from the mixed region to the light emitting medium. Preferred oxidizing dopants include various Lewis acids and acceptor compounds, and preferable reducing dopants include alkali metals, alkali metal compounds, alkaline earth metals, rare earth metals, and mixtures thereof. In addition, an organic electroluminescent device emitting white light having two or more light emitting layers can be manufactured by using the reducing dopant layer as a charge generating layer.

The formation of each layer of the organic electroluminescent device of the present invention is any one of a dry film deposition method such as vacuum deposition, sputtering, plasma, ion plating, or a wet film deposition method such as spin coating, dip coating, and flow coating. The method of can be applied.

In the case of the wet film formation method, a thin film is formed by dissolving or dispersing the material forming each layer in an appropriate solvent such as ethanol, chloroform, tetrahydrofuran, dioxane, etc., and the solvent is dissolved or dispersed in the material forming each layer. It can be made, and any one may be used as long as there is no problem with the film forming property.

Hereinafter, for a detailed understanding of the present invention, an organic electroluminescent compound according to the present invention, a method of manufacturing the same, and light emission characteristics of the device will be described with reference to the representative compound of the present invention.

[Example 1] Preparation of Compound H-1

Preparation of compound 2-1

In a flask, 1,4-dibromonaphthalene 50g (174.8mmol), pinacol diborane 98g (391.6mmol), bis (triphenylphosphine) palladium (II) dichloride [PdCl ₂ (PPh ₃ ) ₂ ] 12g (17.8mmol), potassium acetate (KOAc) 76g (769.1mmol), and tetrahydrofuran (THF) 1L were added and stirred under reflux for 5 hours. After the reaction was completed, the organic layer was extracted with ethyl acetate (EA), residual moisture was removed using magnesium sulfate, dried, and separated by column to obtain 60 g (yield: 94%) of compound 2-1.

Preparation of compound 2-2

In a flask, compound 2-1 60g (157.8mmol), 1-bromo-2-nitrobenzene 96g (473.4mmol), tetrakis (triphenylphosphine) palladium (O) [Pd (PPh ₃ ) ₄ ] 18.3 g ( 15.7mmol), _{240 mL of 2M Na 2} CO _3, 240 mL of ethanol (EtOH), and 500 mL of toluene were dissolved and refluxed at 120° C. for 5 hours. After the reaction was completed, the organic layer was extracted with ethyl acetate, residual moisture was removed using magnesium sulfate, dried, and separated by column to give 50 g (yield: 85%) of compound 2-2.

Preparation of compound 2-3

Compound 2-2 (43g, 116.1mmol), triphenylphosphine (PPh ₃ ) 61g (232.2mmol) and 600 mL of dichlorobenzyl (DCB) were dissolved in a flask and refluxed at 150° C. for 5 hours. Upon completion of the reaction, the mixture was distilled and pulverized with MeOH to obtain 22 g of compound 2-3 (yield: 56%).

Preparation of compound 2-4

In a flask, compound 2-3 (22 g, 65.0 mmol), iodobenzene 11 mL (97.5 mmol), CuI 6.2 g (32.5 mmol), K ₃ PO ₄ 42 g (195 mmol), ethylenediamine (EDA) 9 mL (130 mmol) and toluene After dissolving 300mL, it was refluxed at 120°C for 5 hours. After the reaction was completed, the organic layer was extracted with ethyl acetate, residual moisture was removed using magnesium sulfate, dried, and separated by column to give 18 g (yield: 67%) of compound 2-4.

Preparation of compound 2-5

Compound 2-4 (18g, 43.4mmol), PPh ₃ 25g (108.5mmol), and 220 mL of DCB were dissolved in a flask and refluxed at 150° C. for 5 hours. After the reaction was completed, the mixture was distilled and pulverized with MeOH to obtain 11 g of compound 2-5 (yield: 70%).

Preparation of compound H-1

4 g (10.47 mmol) of compound 2-5 and 4.2 g (15.7 mmol) of compound 1-9 were dissolved in 50 mL of dimethylformamide (DMF), and 0.6 g of NaH (15.71 mmol, 60% in mineral oil) was added. After stirring at room temperature for 12 hours, methanol and distilled water were added. The resulting solid was filtered under reduced pressure and separated by column to obtain 4.2 g of compound H-1 (yield: 65%).

[Example 2] Preparation of Compound H-62

Preparation of compound 3-1

Compound 2-2 (55 g, 0.148 mol) was added to the flask, PPh ₃ (78 g, 0.297 mol) and 1100 mL of DCB were added, and the reaction mixture was heated to 190° C. and stirred for 5 hours. After the reaction was over, DCB was removed using a distillation apparatus, the mixture was washed with distilled water, extracted with EA, the organic layer _{was dried with MgSO 4} , and the solvent was removed by a rotary evaporator, followed by purification with a column, and compound 3-1 (35 g, 78%). ).

Preparation of compound 3-2

Put compound 3-1 (9.4g, 0.031mol) into a flask and compound iodobenzene (6.3g, 0.031mol), CuI (2.95g, 0.015mol), K ₂ CO ₃ (4.3g, 0.031mol), EDA ( 2 mL, 0.031 mol) and 94 mL of toluene were added, then the reaction mixture was heated to 120° C. and stirred for 5 hours. After the reaction was completed, the mixture was washed with distilled water, extracted with EA, and the organic layer _{was dried over MgSO 4,} and then the solvent was removed by a rotary evaporator and purified by column to obtain compound 3-2 (11g, 93%).

Preparation of compound 3-3

Compound 3-2 (11 g, 0.030 mol) was added to the flask and compound 1-bromo-4-iodobenzene (17 g, 0.060 mol), Cu (5.7 g, 0.090 mol), K ₂ CO ₃ (21 g, 0.150 mol) ), 18-Crown-6 (1.6 g, 0.006 mol) and 115 mL of DCB were added, the reaction mixture was heated to 190° C. and stirred for 12 hours. After DCB was removed using a distillation apparatus, the mixture was washed with distilled water, extracted with EA, and the organic layer _{was dried over MgSO 4} , and the solvent was removed by a rotary evaporator and then purified by column to obtain compound 3-3 (14g, 87%).

Preparation of compound 3-4

Compound 3-3 (14 g, 0.026 mol) was put into a flask, and a nitrogen atmosphere was made, and 200 mL of THF was added, and the reaction mixture was stirred at -78°C for 20 minutes. n-Butyl lithium (n-BuLi) (2.5M) (12.5 mL, 0.031 mol) was slowly added to the reaction flask. The reaction mixture was stirred at -78°C for 40 minutes. 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (8 mL, 0.039 mol) was added to the reaction flask and stirred at room temperature for 12 hours. After the reaction was completed, the mixture was washed with distilled water, extracted with EA, and the organic layer _{was dried over MgSO 4} , and the solvent was removed by a rotary evaporator, followed by column purification to obtain compound 3-4 (11g, 73%).

Preparation of compound H-62

Compound 3-4 (2g, 0.003mol) was added to the flask and compound 1-9 (784mg, 0.003mol), Pd(PPh ₃ ) ₄ (230mg, 0.23mmol), K ₂ CO ₃ (2M, 5mL), EtOH 5mL And after adding 10 mL of toluene, the reaction mixture was heated to 120° C. and stirred for 7 hours. After the reaction was completed, the mixture was washed with distilled water, extracted with EA, and the organic layer _{was dried over MgSO 4} , and the solvent was removed by a rotary evaporator, followed by column purification to obtain compound H-62 (1.5g, 71%).

[Example 3] Preparation of Compound H-13

Compound 4-1 (14g, 0.043mol), Compound 4-2 (18.4g, 0.065mol), CuI (4.1g, 0.021mol), ethylenediamine (2.9mL, 0.043mol), Cs ₂ CO ₃ (27.5g 0.129 mol) and 400 mL of toluene were added to the flask and stirred at 120° C. for 12 hours. After the reaction was completed, the mixture was washed with distilled water, extracted with ethyl acetate (EA), and the organic layer _{was dried over MgSO 4} , and the solvent was removed by a rotary evaporator and then purified by column to obtain compound H-13 (8.5g, 43%).

[Example 4] Preparation of Compound H-90

Preparation of compound 5-2

Compound 4-1 (14g, 0.043mol), Compound 5-1 (18.4g, 0.065mol), CuI (4.1g, 0.021mol), ethylenediamine (2.9mL, 0.043mol), Cs ₂ CO ₃ (27.5g 0.129 mol) and 400 mL of toluene were added to the flask and stirred at 120° C. for 12 hours. After the reaction was completed, the mixture was washed with distilled water, extracted with ethyl acetate (EA), and the organic layer _{was dried over MgSO 4} , and the solvent was removed by a rotary evaporator and then purified by column to obtain compound 5-2 (8.5g, 43%).

Preparation of compound 5-3

Compound 5-2 (7.3 g, 0.015 mol) was added to the flask and 4,4,4',4',5,5,5',5'-octamethyl-2,2'-bi (1,3,2 -After adding dioxaborolane) (5.9 g, 0.023 mol), potassium acetate (3.8 g, 0.038 mol), PdCl ₂ (PPh ₃ ) ₂ (561 mg, 0.008 mol) and 70 mL of 1,4-dioxane , The reaction mixture was heated to 150° C. and stirred for 5 hours. After the reaction was completed, the mixture was washed with distilled water, extracted with EA, and the organic layer _{was dried over MgSO 4} , and the solvent was removed by a rotary evaporator, followed by column purification to obtain compound 5-3 (5.0 g, 68%).

Preparation of compound H-90

Put compound 5-3 (2.5g, 0.0048mol) into a flask and compound 4-2 (1.0g, 0.0044 mol), Pd(PPh ₃ ) ₄ (230mg, 0.0005mmol), K ₂ CO ₃ (2M, 6.3mL) After adding 6.3 mL of EtOH and 13 mL of toluene, the reaction mixture was heated to 120° C. and stirred for 7 hours. After the reaction was completed, the mixture was washed with distilled water, extracted with EA, and the organic layer _{was dried over MgSO 4} , and the solvent was removed by a rotary evaporator, followed by column purification to obtain compound H-90 (2.1g, 84%).

[Example 5] Preparation of Compound H-9

Preparation of compound 6-2

Compound 6-1 (15g, 94.23mmol), 2-chloroiodobenzene (12.6mL, 103.65mmol), palladium (II) acetate [Pd(OAc) ₂ ] (0.84g, 3.76mmol), 50% t-butyl Phosphine (3.6 mL, 7.53 mmol) and sodium t-butoxide (22.6 g, 235.57 mmol) were dissolved in 480 mL of toluene and refluxed at 120° C. for 4 hours. After the reaction was completed, the mixture was extracted with dichloromethane/purified water and separated by a column to obtain compound 6-2 (10.4g, 41%).

Preparation of compound 6-3

Compound 6-2 (9.4 g, 34.93 mmol), 2-chloroiodobenzene (4.25 mL, 34.93 _{mmol), Cu 2} O (1.5 g, 10.48 mmol), picolinic acid (2.6 g, 20.96 mmol) and cesium carbonate (23g, 69.87mmol) was dissolved in 170 mL of acetonitrile and then refluxed at 100° C. for 12 hours. Upon completion of the reaction, extraction was performed with dichloromethane and separated by column to obtain compound 6-3 (4g, 30%).

Preparation of compound 6-4

Compound 6-3 (4g, 10.55mmol), Pd(OAc) ₂ (0.23g, 1.055mmol), ligand (0.77g, 2.11mmol) and cesium carbonate (13.7g, 42.2mmol) in 50mL of N-methylpyrrolidone After dissolving in, it was refluxed at 220° C. for 3 hours. After the reaction was completed, the mixture was extracted with dichloromethane/purified water and separated by column to obtain compound 6-4 (2.5g, 78%).

Preparation of compound H-9

Compound 6-4 (4g, 13.01mmol) and compound 4-2 (3.1g, 13.01mmol) were dissolved in 50 mL of dimethylformamide (DMF), and NaH (1.56g, 39.03mmol, 60% in mineral oil) was added. . After stirring at room temperature for 12 hours, methanol and distilled water were added. The resulting solid was filtered under reduced pressure and separated by column to obtain compound H-9 (1.7g, 25.5%).

[Device Example 1] Fabrication of an OLED device using the organic electroluminescent compound according to the present invention

An OLED device having a structure using the organic electroluminescent compound of the present invention was fabricated. First, the transparent electrode ITO thin film (15Ω/□) obtained from OLED glass (manufactured by Samsung-Corning) was ultrasonically washed sequentially using trichloroethylene, acetone, ethanol, and distilled water, and then stored in isopropanol. Was used. Next, after mounting the ITO substrate on the substrate holder of the vacuum evaporation equipment, N ¹ ,N ^1' -([1,1'-biphenyl]-4,4'-diyl)bis(N ¹ -(naphthalen- ^{1-yl)-N 4} ,N ⁴ -diphenylbenzene-1,4-diamine) and ^{exhaust until the vacuum level in the chamber reaches 10 -6} torr, and then apply current to the cell. Then, it was evaporated to deposit a hole injection layer having a thickness of 60 nm on the ITO substrate. Next, N,N'-di(4-biphenyl)-N,N'-di(4-biphenyl)-4,4'-diaminobiphenyl was put in another cell in the vacuum deposition equipment, and the current By applying and evaporation, a hole transport layer having a thickness of 20 nm was deposited on the hole injection layer. After putting compound H-90 as a host in one cell of the vacuum evaporation equipment and compound D-88 as a dopant in another cell, the holes are evaporated at different rates and doped in an amount of 4% by weight, respectively. A light emitting layer having a thickness of 30 nm was deposited on the transfer layer. Then, 2-(4-(9,10-di(naphthalen-2-yl)anthracen-2-yl)phenyl)-1-phenyl-1H-benzo[d]imidazole was put in one cell, and another cell After lithium quinolate was added to, the two materials were evaporated at the same rate and doped in an amount of 50% by weight, respectively, thereby depositing an electron transport layer of 30 nm on the light emitting layer. Subsequently, lithium quinolate was deposited to a thickness of 2 nm as an electron injection layer, and then an Al anode was deposited to a thickness of 150 nm using other vacuum deposition equipment to fabricate an OLED device. For each material, each compound was used by vacuum sublimation purification under ^{10 -6 torr.}

As a result, a current of 14.6 mA/cm ² flowed at a voltage of 3.5 V, a red light emission of 980 cd/m ² was observed, and the time taken for the light emission to fall to 90% at a luminance of 5000 nit was more than 100 hours.

[Comparative Example 1] Fabrication of OLED devices using conventional light-emitting materials

을, 도판트에는 화합물 D-88을 사용한 것 외에는 소자 실시예1과 동일한 방법으로 OLED 소자를 제작하였다. Compound C-1 in the host as a light emitting material

In addition, an OLED device was manufactured in the same manner as in Device Example 1, except that Compound D-88 was used as the dopant.

As a result, a current of 15.8 mA/cm ² flowed at a voltage of 3.6 V, a red light emission of 1000 cd/m ² was observed, and the time taken for the light emission to drop to 90% at a luminance of 5000 nit was 80 hours or more.

The organic electroluminescent compound according to the present invention has excellent luminous efficiency, has a long driving life, and can manufacture an organic electroluminescent device with improved current efficiency and power efficiency.

Claims (8)

delete An organic electroluminescent compound represented by the following formula (2).
[Formula 2]

In Chemical Formula 2,
L ₁ is a single bond, a substituted or unsubstituted (3-30 membered) heteroarylene, a substituted or unsubstituted (C6-C30)arylene, or (C1-C30)alkylene;
X ₁ is NR ₅ ;
X ₂ to X ₅ are each independently -CR ₈ -;
Y ₂ is -CR ₉ -;
R ₁ to R ₄ are each independently hydrogen, deuterium, halogen, cyano, carboxyl, nitro, hydroxy, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C3-C30)cycloalkyl , Substituted or unsubstituted (C3-C30)cycloalkenyl, substituted or unsubstituted (3-7 member) heterocycloalkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (3- 30 membered) heteroaryl, substituted or unsubstituted (C6-C30) arylamine, -NR ₁₀ R ₁₁ or -SiR ₁₂ R ₁₃ R ₁₄ ;
R ₅ , R ₈ and R ₉ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (3- 30 membered) heteroaryl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (5-7 membered) heterocycloalkyl, substituted or unsubstituted (C6-C30) ar (C1-C30) Alkyl, -NR ₁₀ R ₁₁ , -SiR ₁₂ R ₁₃ R ₁₄ , cyano, nitro or hydroxy;
R ₁₀ and R ₁₁ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, or substituted or unsubstituted (3-30 membered ) Heteroaryl;
R ₁₂ to R ₁₄ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (3-30 membered) Heteroaryl, substituted or unsubstituted (5-7 membered) heterocycloalkyl, or substituted or unsubstituted (C3-C30) cycloalkyl, or substituted or unsubstituted (3-30 membered) monocyclic with an adjacent substituent Or it may form a polycyclic alicyclic or aromatic ring;
The alicyclic or aromatic ring carbon atom may be replaced by one or more heteroatoms selected from nitrogen, oxygen and sulfur;
The heteroaryl(ene) and heterocycloalkyl contain one or more heteroatoms selected from B, N, O, S, P(=O), Si and P;
a, b, c and d are each independently an integer of 1 to 4, and when an integer of 2 or more, each of R ₁ , R ₂ , R ₃ and R ₄ may be the same or different. An organic electroluminescent compound represented by the following formula (3).
[Formula 3]

In Chemical Formula 3,
L ₁ is a single bond, a substituted or unsubstituted (3-30 membered) heteroarylene, a substituted or unsubstituted (C6-C30)arylene, or (C1-C30)alkylene;
X ₁ is NR ₅ , -CR ₆ R ₇ , O or S;
X ₂ to X ₅ are each independently -CR ₈ -;
Y ₁ is -CR ₉ -;
R ₁ to R ₄ are each independently hydrogen, deuterium, halogen, cyano, carboxyl, nitro, hydroxy, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C3-C30)cycloalkyl , Substituted or unsubstituted (C3-C30)cycloalkenyl, substituted or unsubstituted (3-7 member) heterocycloalkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (3- 30 membered) heteroaryl, substituted or unsubstituted (C6-C30) arylamine, -NR ₁₀ R ₁₁ or -SiR ₁₂ R ₁₃ R ₁₄ ;
R ₅ to R ₉ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (3-30 membered) Heteroaryl, substituted or unsubstituted (C3-C30)cycloalkyl, substituted or unsubstituted (5-7 membered) heterocycloalkyl, substituted or unsubstituted (C6-C30)ar(C1-C30)alkyl,- NR ₁₀ R ₁₁ , -SiR ₁₂ R ₁₃ R ₁₄ , cyano, nitro or hydroxy;
R ₁₀ and R ₁₁ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, or substituted or unsubstituted (3-30 membered ) Heteroaryl;
R ₁₂ to R ₁₄ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (3-30 membered) Heteroaryl, substituted or unsubstituted (5-7 membered) heterocycloalkyl, or substituted or unsubstituted (C3-C30) cycloalkyl, or substituted or unsubstituted (3-30 membered) monocyclic with an adjacent substituent Or it may form a polycyclic alicyclic or aromatic ring;
The alicyclic or aromatic ring carbon atom may be replaced by one or more heteroatoms selected from nitrogen, oxygen and sulfur;
The heteroaryl(ene) and heterocycloalkyl contain one or more heteroatoms selected from B, N, O, S, P(=O), Si and P;
a, b, c and d are each independently an integer of 1 to 4, and when an integer of 2 or more, each of R ₁ , R ₂ , R ₃ and R ₄ may be the same or different. delete The method of claim 2 or 3, wherein L ₁ is a single bond, or a substituted or unsubstituted (C6-C30)arylene, and R ₁ to R ₄ are each independently hydrogen, cyano, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted (3-30 membered) heteroaryl or -NR ₁₀ R ₁₁ , and R ₅ to R ₉ are each independently hydrogen Or a substituted or unsubstituted (C6-C30) aryl, and R ₁₀ and R ₁₁ are each independently a substituted or unsubstituted (C6-C30) aryl organic electroluminescent compound. The method according to claim 2 or 3, wherein in L ₁ and R ₁ to R ₁₄ , substituted (C1-C30)alkyl, substituted (C3-C30)cycloalkyl, substituted (C3-C30)cycloalkenyl, substituted (3 -7 membered) heterocycloalkyl, substituted (5-7 membered) heterocycloalkyl, substituted (C6-C30) aryl (ene), substituted (3-30 membered) heteroaryl (ene), substituted (C6-C30) aryl Amine, substituted (C6-C30) ar (C1-C30) alkyl and substituted (3-30 membered) monocyclic or polycyclic alicyclic or aromatic ring substituents are each independently deuterium, halogen, cyano, carboxyl, nitro , Hydroxy, (C1-C30)alkyl, halo (C1-C30)alkyl, (C2-C30)alkenyl, (C2-C30)alkynyl, (C1-C30)alkoxy, (C1-C30)alkylthio, (C3-C30)cycloalkyl, (C3-C30)cycloalkenyl, (3-7 member)heterocycloalkyl, (C6-C30)aryloxy, (C6-C30)arylthio, (C6-C30)arylo Substituted or unsubstituted (3-30 membered) heteroaryl, (3-30 membered) heteroaryl substituted or unsubstituted (C6-C30)aryl, tri(C1-C30)alkylsilyl, tri(C6-C30) Arylsilyl, di(C1-C30)alkyl(C6-C30)arylsilyl, (C1-C30)alkyldi(C6-C30)arylsilyl, amino, mono or di(C1-C30)alkylamino, mono or di( C6-C30)arylamino, (C1-C30)alkyl(C6-C30)arylamino, (C1-C30)alkylcarbonyl, (C1-C30)alkoxycarbonyl, (C6-C30)arylcarbonyl, di( C6-C30)arylboronyl, di(C1-C30)alkylboronyl, (C1-C30)alkyl(C6-C30)arylboronyl, (C6-C30)ar(C1-C30)alkyl and ( An organic electroluminescent compound that is at least one selected from the group consisting of C1-C30)alkyl(C6-C30)aryl. The organic electroluminescent compound according to claim 2 or 3, wherein the compound represented by Formula 2 or 3 is selected from the following compounds.

An organic electroluminescent device comprising the compound according to claim 2 or 3.