KR102549641B1 - Organic Electroluminescent Compound 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. By using the organic electroluminescent compound of the present invention, an organic electroluminescent device having excellent light emitting properties can be manufactured.

Description

Organic Electroluminescent Compound and Organic Electroluminescent Device Comprising the Same}

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

Among display devices, an electroluminescent device (EL device) is a self-luminous display device and has advantages of a wide viewing angle, excellent contrast, and fast 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 [Appl. Phys. Lett. 51, 913, 1987].

The most important factor determining luminous efficiency in an organic electroluminescent device is a light emitting material. Although fluorescent materials have been widely used as light emitting materials so far, research on the development of phosphorescent light emitting materials has been widely conducted in that phosphorescent light emitting materials can theoretically improve luminous efficiency up to 4 times compared to fluorescent light emitting materials due to the mechanism of electroluminescence. It is becoming. Until now, the iridium (III) complex series has been widely known as a phosphorescent light emitting material, and for each RGB, bis(2-(2'-benzothienyl)-pyridinato-N,C-3')iridium (acetylacetonate ) [(acac)Ir(btp) ₂ ], tris(2-phenylpyridine)iridium [Ir(ppy) ₃ ] and bis(4,6-difluorophenylpyridinato-N,C2)picolinate Materials such as toiridium (Firpic) are known.

In the prior art, 4,4'-N,N'-dicarbazole-biphenyl (CBP) was most widely known as a host material for phosphorescence. Recently, Bathocuproine (BCP) and aluminum (III) bis (2-methyl-8-quinolinate) (4-phenylphenolate) ( Balq) has been used as a host material to develop high-performance organic electroluminescent devices.

However, conventional materials are advantageous in terms of light emitting properties, but have the following disadvantages: (1) low glass transition temperature and low thermal stability, which deteriorates during a high-temperature deposition process in a vacuum and reduces the lifespan of the device. (2) Power efficiency = [(π/voltage) × current efficiency] in organic light emitting devices, so power efficiency is inversely proportional to voltage. Although the current efficiency (cd/A) is higher than that of the light emitting device, there is no significant advantage in terms of power efficiency (lm/w) because the driving voltage is also considerably higher. (3) In addition, when used in an organic electroluminescent device, it is not satisfactory in terms of operating life, and improvement in luminous efficiency is still required.

Meanwhile, the organic electroluminescent device has a multilayer structure including a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer in order to increase its efficiency and stability. At this time, selection of a compound included in the hole transport layer is recognized as a means capable of improving device characteristics such as hole transport efficiency to the light emitting layer, luminous efficiency, and lifetime.

In this regard, copper phthalocyanine (CuPc), 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB), N,N as hole injection and transport materials in organic electroluminescent devices '-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (TPD), 4,4',4"-tris(3-methylphenyl) Phenylamino)triphenylamine (MTDATA), etc. have been used, but when these materials are used, the organic electroluminescent device has a problem in that the quantum efficiency and lifespan decrease. This is because thermal stress occurs between the anode and the hole injection layer, and the lifetime of the device is rapidly reduced by this thermal stress. Because of this, the hole-electron charge balance is broken, and thus the quantum efficiency (cd/A) is lowered.

Therefore, development of a hole transport layer for improving durability of an organic EL device is still required.

Synthetic Metals Vol.162 (2012) pp.2059-2062 discloses methyl compounds substituted with phenyl, diphenylaniline and dibenzofuran as compounds for organic electroluminescent devices. However, the above document does not specifically disclose an organic electroluminescent device using a compound having a structure in which all of the aryls of diarylamine are not phenyl.

Synthetic Metals Vol.162 (2012) pp.2059-2062 (published on November 9, 2012)

An object of the present invention is to provide an organic electroluminescent compound having excellent light emitting properties.

As a result of intensive research to solve the above technical problems, the present inventors have found that an organic electroluminescent compound represented by the following Chemical Formula 1 achieves the above object and completed the present invention.

[Formula 1]

In Formula 1,

Ar ₁ and Ar ₂ are each independently a substituted or unsubstituted (C6-C30)aryl or a substituted or unsubstituted (5-30 membered) heteroaryl;

However, the case where both Ar ₁ and Ar ₂ are phenyl is excluded;

L ₁ and L ₂ are each independently a single bond, a substituted or unsubstituted (C6-C30)arylene, or a substituted or unsubstituted (3-30 membered) heteroarylene;

X is O, S, CR ₅ R ₆ or NR ₇ ;

R ₁ to R ₇ 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 membered) heterocycloalkyl, substituted or unsubstituted (C6-C30) aryl, substituted or unsubstituted (3- 30-membered) heteroaryl, -NR ₈ R ₉ or -SiR ₁₀ R ₁₁ R ₁₂ or may form a substituted or unsubstituted (C3-C30) monocyclic or polycyclic alicyclic or aromatic ring with adjacent substituents; , a carbon atom of the alicyclic or aromatic ring may be replaced with one or more heteroatoms selected from nitrogen, oxygen and sulfur;

R ₈ to R ₁₂ 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 membered) heterocycloalkyl, substituted or unsubstituted (C6-C30) aryl, or substituted or unsubstituted (3 -30 member) heteroaryl;

a is an integer of 1 to 4, and when an integer of 2 or greater, each R ₁ may be the same as or different from each other;

b is an integer of 1 to 3, and when it is an integer of 2 or more, each R ₂ may be the same as or different from each other;

c and d are each independently an integer of 1 to 5, and when c or d is an integer of 2 or greater, each R ₃ and each R ₄ may be the same as or different from each other;

The heteroaryl (ene) and heterocycloalkyl each independently include one or more heteroatoms selected from B, N, O, S, Si and P.

The organic electroluminescent compound according to the present invention has the advantage of being able to manufacture an organic electroluminescent device having excellent light emitting properties.

Although the present invention is described in more detail below, it is for illustrative purposes only and should not be construed in any way to limit the scope of the present invention.

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

A more detailed description of the organic electroluminescent compound represented by Chemical Formula 1 is as follows.

"(C1-C30)alkyl" as described in the present invention means straight-chain or branched-chain alkyl having 1 to 30 carbon atoms constituting the chain, preferably 1 to 10 carbon atoms, and 1 to 6 carbon atoms it is more preferable Specific examples of the alkyl include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl. As used herein, "(C2-C30)alkenyl" means a straight or branched chain alkenyl having 2 to 30 carbon atoms constituting the chain, preferably 2 to 20 carbon atoms, and more preferably 2 to 10 carbon atoms. desirable. Specific examples of the alkenyl include vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 2-methylbut-2-enyl, and the like. As used herein, "(C2-C30)alkynyl" means straight or branched chain alkynyl having 2 to 30 carbon atoms constituting the chain, preferably 2 to 20 carbon atoms, and more preferably 2 to 10 carbon atoms. desirable. Examples of the alkynyl include ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 3-butynyl, and 1-methylpent-2-ynyl. As used herein, “(C3-C30)cycloalkyl” means a monocyclic or polycyclic hydrocarbon having 3 to 30 carbon atoms in the ring skeleton, 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 membered) heterocycloalalkyl" has 3 to 7 ring skeleton atoms, and at least one heteroatom selected from the group consisting of B, N, O, S, Si and P, preferably O, It means a cycloalkyl containing at least one heteroatom selected from S and N, and examples thereof include tetrahydrofuran, pyrrolidine, thiolane, and tetrahydropyran. As used herein, “(C6-C30)aryl(ene)” means a monocyclic or fused ring radical derived from an aromatic hydrocarbon having 6 to 30 carbon atoms in the ring skeleton, and preferably 6 to 20 carbon atoms in the ring skeleton, , more preferably 6 to 15. Examples of the aryl include phenyl, biphenyl, terphenyl, naphthyl, binapthyl, phenylnaphthyl, naphthylphenyl, fluorenyl, phenylfluorenyl, benzofluorenyl, dibenzofluorenyl, and phenane. trenyl, phenylphenanthrenyl, anthracenyl, indenyl, triphenylenyl, pyrenyl, tetracenyl, perylenyl, chrysenyl, naphthacenyl, fluoranthenyl, and the like. As used herein, “(5-30 membered) heteroaryl (ene)” refers to an aryl group having 5 to 30 ring skeleton atoms and containing one or more heteroatoms selected from the group consisting of B, N, O, S, Si and P. it means. The number of hetero atoms 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 includes a form in which one or more heteroaryl 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, single ring heteroaryl such as pyridazinyl, benzofuranyl, benzothiophenyl, isobenzofuranyl, dibenzofuranyl, di Benzothiophenyl, Benzonaphthothiophenyl, Benzoimidazolyl, Benzothiazolyl, Benzoisothiazolyl, Benzoisoxazolyl, Benzoxazolyl, Isoindolyl, Indolyl, Indazolyl, Benzothiadiazolyl, Quinolyl , isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, carbazolyl, phenoxazinyl, phenanthridinyl, fused ring system heteroaryl such as benzodioxolyl, and the like. As used herein, “halogen” includes F, Cl, Br and I atoms.

In addition, 'substitution' in the description of "substituted or unsubstituted" described in the present invention means that a hydrogen atom in a functional group is replaced with another atom or another functional group (ie, a substituent). Substituted alkyl, substituted cycloalkyl, substituted cycloalkenyl, substituted heterocycloalkyl, substituted aryl (ene), substituted heteroaryl in Ar ₁ , Ar ₂ , L ₁ , L ₂ and R ₁ to R ₁₂ of Formula 1 ( Ren), and substituents of substituted monocyclic or polycyclic alicyclic or aromatic rings 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 membered) heterocycloalkyl, (C6-C30) aryloxy, (C6-C30) arylthio, (3-30 membered) heteroaryl unsubstituted or substituted with (C6-C30) aryl, (3-30 membered) (C6-C30) aryl, tri (C1-C30) alkylsilyl, tri (C6-C30) arylsilyl, di (C1-C30) alkyl (C6-C30) arylsilyl, unsubstituted or substituted with heteroaryl, (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) The group consisting of )alkylboronyl, (C1-C30)alkyl(C6-C30)arylboronyl, (C6-C30)ar(C1-C30)alkyl and (C1-C30)alkyl(C6-C30)aryl It means one or more selected from, and each independently a group consisting of (C1-C6) alkyl, (C6-C25) aryl, tri (C6-C12) arylsilyl and (C1-C6) alkyl (C6-C15) aryl. It is preferably one or more selected from

The compound of Formula 1 may be represented by one of Formulas 2 and 3 below.

[Formula 2]

[Formula 3]

In Formulas 2 and 3,

Ar ₁ , Ar ₂ , L ₁ , L ₂ , X, R ₁ to R ₄ and a to d are as defined in Formula 1.

In Formula 1, Ar ₁ and Ar ₂ are each independently a substituted or unsubstituted (C6-C30)aryl or a substituted or unsubstituted (5-30 membered) heteroaryl, provided that Ar ₁ and Ar ₂ are Except for the case where all are phenyl, preferably each independently substituted or unsubstituted (C6-C20) aryl, more preferably each independently (C1-C6) alkyl, (C6-C25) aryl, tri( It is (C6-C20) aryl unsubstituted or substituted with C6-C12) arylsilyl or (C1-C6) alkyl (C6-C15) aryl.

Specifically, Ar ₁ and Ar ₂ may each independently be represented by one of the following structures.

Wherein L ₁ and L ₂ are each independently a single bond, a substituted or unsubstituted (C6-C30)arylene, or a substituted or unsubstituted (3-30 membered) heteroarylene, and preferably each independently a single A bond or a substituted or unsubstituted (C6-C12)arylene, more preferably a single bond or unsubstituted (C6-C12)arylene each independently.

X is O, S, CR ₅ R ₆ or NR ₇ .

Wherein R ₁ to R ₇ are each independently hydrogen, deuterium, halogen, cyano, carboxyl, nitro, hydroxy, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C3-C30)cyclo Alkyl, substituted or unsubstituted (C3-C30) cycloalkenyl, substituted or unsubstituted (3-7 membered) heterocycloalkyl, substituted or unsubstituted (C6-C30) aryl, substituted or unsubstituted (3 -30-membered) heteroaryl, -NR ₈ R ₉ or -SiR ₁₀ R ₁₁ R ₁₂ , or may form a substituted or unsubstituted (C3-C30) monocyclic or polycyclic alicyclic or aromatic ring with adjacent substituents And, the carbon atoms of the alicyclic or aromatic ring may be replaced with one or more heteroatoms selected from nitrogen, oxygen and sulfur, preferably each independently hydrogen, substituted or unsubstituted (C1-C6) alkyl, or It is a substituted or unsubstituted (C6-C12) aryl, and more preferably independently hydrogen, unsubstituted (C1-C6) alkyl, or unsubstituted (C6-C12) aryl.

Wherein R ₈ to R ₁₂ are each independently hydrogen, deuterium, halogen, cyano, carboxyl, nitro, hydroxy, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C3-C30)cyclo Alkyl, substituted or unsubstituted (C3-C30) cycloalkenyl, substituted or unsubstituted (3-7 membered) heterocycloalkyl, substituted or unsubstituted (C6-C30) aryl, or substituted or unsubstituted ( 3-30 membered) heteroaryl, preferably each independently substituted or unsubstituted (C6-C12) aryl, more preferably each independently unsubstituted (C6-C12) aryl.

According to one aspect of the present invention, in Formula 1, Ar ₁ and Ar ₂ are each independently a substituted or unsubstituted (C6-C20)aryl; L ₁ and L ₂ are each independently a single bond or a substituted or unsubstituted (C6-C12)arylene; X is O, S, CR ₅ R ₆ or NR ₇ ; R ₁ to R ₇ are each independently hydrogen, substituted or unsubstituted (C1-C6)alkyl, or substituted or unsubstituted (C6-C12)aryl.

According to another aspect of the present invention, in Formula 1, Ar ₁ and Ar ₂ are each independently (C1-C6)alkyl, (C6-C25)aryl, tri(C6-C12)arylsilyl or (C1-C6) ) (C6-C20) aryl unsubstituted or substituted with alkyl (C6-C15) aryl; L ₁ and L ₂ are each independently a single bond or unsubstituted (C6-C12)arylene; X is O, S, CR ₅ R ₆ or NR ₇ ; R ₁ to R ₇ are each independently hydrogen, unsubstituted (C1-C6)alkyl, or unsubstituted (C6-C12)aryl.

In Formula 1, the case where both Ar ₁ and Ar ₂ are phenyl is excluded. If the arylamine conjugation length is too short, side reactions such as a cyclization reaction may occur when the compound of Formula 1 becomes an exciton, so that charges cannot be efficiently transferred.

In addition, since the three-dimensional shape varies depending on how substituents are attached to diphenylmethyl in Chemical Formula 1, it greatly affects the efficiency of the device. The reason is that when a molecule such as dibenzofuran is bonded at position 3 or 4 (position 1 or 2 in carbazole), it is located in a spatially close position to the phenyl of the substituent, and is located in position 2 (position 2 in carbazole). position 3), less polar oxygen atoms are exposed in space than when bonded at position 3), and this positively affects the charge transfer of the material and the characteristics of the device. This is because if a large number of atoms with high polarity are exposed in space, they may interact with charges in the device and act as a factor hindering efficient transfer.

On the other hand, since a molecule such as fluorene does not have a polar element, bonding at position 3, which is the most common form, is the most preferred embodiment.

The organic electroluminescent compound of Chemical Formula 1 may be more specifically exemplified as the following compounds, but is not limited thereto.

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, as shown in the following reaction scheme.

[Scheme 1]

In Reaction Scheme 1, Ar ₁ , Ar ₂ , L ₁ , L ₂ , X, R ₁ to R ₄ and a to d are the same as defined in Formula 1.

In addition, the present invention provides an organic electroluminescent material including the organic electroluminescent compound of Chemical Formula 1 and an organic electroluminescent device including the material.

The material may be made of the organic electroluminescent compound of the present invention alone, and may further include conventional materials included in the organic electroluminescent material.

An organic electroluminescent device according to the present invention includes a first electrode; a second electrode; and one or more organic material layers interposed between the first electrode and the second electrode, and the organic material layer may include one or more organic electroluminescent compounds represented by Chemical Formula 1.

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 a light emitting layer, and may further include one or more layers selected from a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, an interlayer, a hole blocking layer, and an electron blocking layer.

The organic electroluminescent compound of the present invention may be included in at least one of the light emitting layer and the hole transport layer. When used in a hole transport layer, the organic electroluminescent compound of the present invention may be included as a hole transport material. When used in a light emitting layer, the organic electroluminescent compound of the present invention may be included as a host material.

The organic electroluminescent device including the organic electroluminescent compound of the present invention may further include one or more compounds other than the organic electroluminescent compound of the present invention as a host material, and may further include one or more dopants.

When the organic electroluminescent compound of the present invention is included as the host material (first host material) of the light emitting layer, other compounds may be included as the second host material. At this time, the weight ratio of the first host material and the second host material ranges from 1:99 to 99:1.

Any known phosphorescent host can be used as a host material for compounds other than the organic electroluminescent compound of the present invention, but those selected from the group consisting of compounds represented by Formulas 11 to 13 below are particularly effective in terms of luminous efficiency. desirable.

[Formula 11]

H-(Cz-L ₄ ) _h -M

[Formula 12]

H-(Cz) _i -L ₄ -M

[Formula 13]

In Formulas 11 to 13,

Cz has the following structure,

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 (3-30 members) Heteroaryl or -SiR ₂₅ R ₂₆ R ₂₇ , 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, substituted or unsubstituted (C6-C30)arylene, or 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 -O-, -S-, -N(R ₃₁ )-, -C(R ₃₂ )(R ₃₃ )-, and Y ₁ and Y ₂ do not exist at the same time;

R ₃₁ to R ₃₃ are each independently substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, or substituted or unsubstituted (5-30 membered) heteroaryl, and 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, and 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 host material are as follows.

[Here, TPS is a triphenylsilyl group]

As the dopant included in the organic electroluminescent device of the present invention, 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-metallated iridium complex compound is still more preferable.

The phosphorescent dopant is preferably selected from the group consisting of compounds represented by Chemical Formulas 101 to 103 below.

[Formula 101] [Formula 102] [Formula 103]

In Formulas 101 to 103, 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, cyano, substituted or unsubstituted (C1-C30)alkoxy, substituted or unsubstituted (C6-C30)aryl or substituted or unsubstituted (C3-C30)cycloalkyl; R ₁₀₆ to R ₁₀₉ may form a substituted or unsubstituted fused ring by linking adjacent substituents, for example, fluorene substituted or unsubstituted with alkyl, dibenzothiophene substituted or unsubstituted with alkyl, Or it is possible to form dibenzofuran substituted or unsubstituted with alkyl; Adjacent substituents of R ₁₂₀ to R ₁₂₃ may be linked to each other to form a substituted or unsubstituted fused ring, for example, an alkyl or aryl substituted or unsubstituted 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; R ₁₂₄ to R ₁₂₇ may form a substituted or unsubstituted fused ring by linking adjacent substituents, for example, fluorene substituted or unsubstituted with alkyl, dibenzothiophene substituted or unsubstituted with alkyl, Or it is possible to form dibenzofuran substituted or unsubstituted with alkyl;

R ₂₀₁ to R ₂₁₁ are each independently hydrogen, deuterium, halogen, halogen-substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C3-C30)cycloalkyl, or substituted or unsubstituted (C6 -C30) aryl, and R ₂₀₈ to R ₂₁₁ may form a substituted or unsubstituted fused ring by linking adjacent substituents to each other, for example, fluorene substituted or unsubstituted with alkyl, substituted or unsubstituted with alkyl dibenzothiophene or alkyl substituted or unsubstituted dibenzofuran can be formed;

r and s are each independently an integer of 1 to 3, and when r or s are each an integer of 2 or more, each R ₁₀₀ may be the same as or different from each other;

e is an integer from 1 to 3;

Specific examples of the phosphorescent dopant material are as follows.

In a further aspect, the present invention provides a composition for preparing an organic electroluminescent device. The composition includes the compound of the present invention as a host material or a hole transport layer material.

In addition, the organic electroluminescent device of the present invention includes a first electrode; a second electrode; and one or more organic material layers interposed between the first electrode and the second electrode, the organic material layer including a light emitting layer, and the light emitting layer may include the composition for an organic electroluminescent device of the present invention.

The organic electroluminescent device of the present invention may include the organic electroluminescent compound of Chemical Formula 1 and at least one compound selected from the group consisting of arylamine-based compounds and styrylarylamine-based compounds.

In addition, in the organic electroluminescent device of the present invention, in addition to the organic electroluminescent compound of Formula 1, the organic material layer is composed of group 1, group 2, period 4, and period 5 transition metals, lanthanum series metals, and organometallics of d-transition elements. It may further include one or more metals or complex compounds selected from the group, and furthermore, the organic material layer may further include a light emitting layer and a charge generation layer.

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 compound of the present invention. In addition, if necessary, a yellow or orange light emitting layer may be further included.

In the organic electroluminescent device of the present invention, a layer selected from a chalcogenide layer, a metal halide layer, and a metal oxide layer (hereinafter referred to as "surface layer") is provided on the inner surface of at least one of the pair of electrodes. It is desirable to arrange the above. Specifically, it is preferable to dispose a metal chalcogenide (including oxide) layer of silicon and aluminum on the surface of the anode on the light emitting medium layer side, and a metal halide layer or metal oxide layer on the surface of the cathode on the light emitting medium layer side. do. In this way, stabilization of driving can be obtained. Preferable 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 There are rare earth metals and the like, and preferable examples of the metal oxide 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 possible to arrange a mixed region of an electron transfer compound and a reducing dopant or a mixed region of a hole transfer compound and an oxidizing dopant on at least one surface of a pair of electrodes manufactured in this way. desirable. Since the electron transfer compound is reduced to negative ions in this way, it is easy to inject and transfer electrons from the mixed region to the light emitting medium. In addition, since the hole transfer compound is oxidized to become a cation, it becomes easy to inject and transfer holes from the mixed region to the light emitting medium. Preferable 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, a white organic electroluminescent device having two or more light emitting layers may be manufactured by using the reducing dopant layer as a charge generation layer.

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

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

Hereinafter, for a detailed understanding of the present invention, the organic electroluminescent compound according to the present invention, its preparation method, and light emitting characteristics of the device will be described with reference to representative compounds of the present invention.

[ Example 1] Preparation of Compound C-1

Preparation of compound 1-1

Benzoyl chloride (45 mL, 376 mmol), 4-dibenzofuryl-boronic acid (40 g, 188.7 mmol), tetrakis (triphenylphosphine) palladium (6.5 g, 5.66 mmol), cesium carbonate (92 g, 283 mmol) and 1 L of toluene were added, followed by stirring at 120°C for 2 hours. After the reaction was completed, the mixture was washed with distilled water and the organic layer was extracted with ethyl acetate. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, it was purified by column chromatography to obtain compound 1-1 (46 g, 90%).

Preparation of compound 1-2

Compound 1-1 (38 g, 140 mmol) and 500 mL of tetrahydrofuran were put in a reaction vessel, and then cooled to 0°C under nitrogen conditions. To the mixture, 60 mL (3 M, 182 mmol) of phenylmagnesium bromide solution was slowly added dropwise. The temperature was raised slowly and stirred under reflux for 3 hours. An aqueous solution of ammonium chloride was added to the reaction solution to terminate the reaction, and extraction was performed with ethyl acetate. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, it was purified by column chromatography to obtain compound 1-2 (29 g, 59%).

Preparation of compounds 1-3

Compound 1-2 (28.5 g, 81 mmol), 4-bromotriphenylamine (53 g, 162 mmol) and 400 mL of methylene chloride (MC) were put in a reaction vessel, and nitrogen conditions were created. 2.5 mL of Eaton's reagent was slowly added dropwise to the mixture. After stirring at room temperature for 2 hours, the reaction was terminated by adding ethanol and distilled water, followed by extraction with methylene chloride. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, it was purified by column chromatography to obtain compound 1-3 (28.5 g, 54%).

Preparation of compound C-1

In a reaction vessel, compound 1-3 (10 g, 15.2 mmol), 2-naphthylboronic acid (3.1 g, 18.2 mmol), tetrakis (triphenylphosphine) palladium (0.7 g, 0.61 mmol), potassium carbonate (5.2 g, 38 mmol), 60 mL of toluene and 20 mL of ethanol were added, 20 mL of distilled water was added, and the mixture was stirred at 120° C. for 3 hours. After the reaction was finished, the mixture was washed with distilled water and the organic layer was extracted with ethyl acetate. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, it was purified by column chromatography to obtain compound C-1 (8.7 g, 81%).

[device manufacturing example 1] organic according to the present invention electric field containing a luminescent compound OLED device manufacturing

An OLED device containing the organic electroluminescent compound of the present invention was prepared. First, a transparent electrode ITO thin film (10Ω/□) on a glass substrate for OLED (manufactured by Geomatec) was washed with ultrasonic waves using acetone, ethanol, and distilled water sequentially, and then stored in isopropanol before use. Next, after mounting the ITO substrate on the substrate holder of the vacuum deposition equipment, N ⁴ ,N ^4' -diphenyl-N ⁴ ,N ^4' -bis(9-phenyl-9H-carbazole- 3-day) -[1,1'-biphenyl] -4,4'-diamine (compound HI-1) was added, and the vacuum in the chamber was evacuated until it reached 10 ^-6 torr, and then a current was applied to the cell. After applying and evaporating, a first hole injection layer having a thickness of 80 nm was deposited on the ITO substrate. Subsequently, 1,4,5,8,9,12-hexaazatriphenylene-hexacarbonitrile (compound HI-2) was put into another cell in the vacuum deposition equipment, and an electric current was applied to the cell to evaporate it, thereby forming a first hole A second hole injection layer having a thickness of 3 nm was deposited on the injection layer. Then N-([1,1'-biphenyl]-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazole-3- 1) Phenyl) -9H-fluoren-2-amine (compound HT-1) was put thereinto, and an electric current was applied to the cell to evaporate it, thereby depositing a first hole transport layer having a thickness of 10 nm on the second hole injection layer. Subsequently, compound C-1 was put into another cell in the vacuum deposition equipment, and an electric current was applied to the cell to evaporate it, and a second hole transport layer having a thickness of 60 nm was deposited on the first hole transport layer. After forming the hole injection layer and the hole transport layer, a light emitting layer was deposited thereon as follows. After putting compound H-1 as a host in one cell of the vacuum deposition equipment and compound D-96 as a dopant in another cell, respectively, the two materials were evaporated at different rates to form a dopant for the dopant and the host as a whole. A light emitting layer having a thickness of 40 nm was deposited on the second hole transport layer by doping with 2% by weight. Then, in two other cells, 2,4-bis(9,9-dimethyl-9H-fluoren-2-yl)-6-(naphthalen-2-yl)-1,3,5-triazine (compound ET-1) and lithium quinolate (compound EI-1) were evaporated at a rate of 1:1 to deposit an electron transport layer having a thickness of 35 nm on the light emitting layer. Subsequently, after depositing lithium quinolate (compound EI-1) to a thickness of 2 nm as an electron injection layer, an Al cathode was deposited to a thickness of 80 nm using another vacuum deposition equipment to manufacture an OLED device.

As a result, a current of 3.67 mA/cm ² flowed, and red light emission of 1000 cd/m ² was confirmed.

[ comparative example 1] conventional organic electric field containing a luminescent compound OLED device manufacturing

N-([1,1'-biphenyl]-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl as the second hole transport layer An OLED device was manufactured in the same manner as in Device Preparation Example 1, except that )-9H-fluorene-2-amine (compound HT-1) was deposited to a thickness of 60 nm.

As a result, a current of 7.5 mA/cm ² flowed, and red light emission of 1000 cd/m ² was confirmed.

It was confirmed that the emission characteristics of the organic electroluminescent compounds developed in the present invention are superior to conventional materials. In addition, the device using the organic electroluminescent compound according to the present invention has excellent light emission characteristics.

Claims (8)

An organic electroluminescent compound represented by Formula 1 below.
[Formula 1]

In Formula 1,
Ar ₁ and Ar ₂ are each independently represented by one of the following structures;

However, the case where both Ar ₁ and Ar ₂ are unsubstituted phenyl is excluded;
L ₁ and L ₂ are each independently a single bond, a substituted or unsubstituted (C6-C30)arylene, or a substituted or unsubstituted (3-30 membered) heteroarylene;
X is O, S, CR ₅ R ₆ or NR ₇ ;
R ₁ to R ₇ 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 membered) heterocycloalkyl, substituted or unsubstituted (C6-C30) aryl, substituted or unsubstituted (3- 30-membered) heteroaryl, -NR ₈ R ₉ or -SiR ₁₀ R ₁₁ R ₁₂ ; A substituted or unsubstituted (C3-C30) monocyclic or polycyclic alicyclic or aromatic ring may be formed together with adjacent substituents, and the carbon atom of the alicyclic or aromatic ring is one or more selected from nitrogen, oxygen and sulfur. can be replaced by a heteroatom;
R ₈ to R ₁₂ 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 membered) heterocycloalkyl, substituted or unsubstituted (C6-C30) aryl, or substituted or unsubstituted (3 -30 member) heteroaryl;
a is an integer of 1 to 4, and when an integer of 2 or greater, each R ₁ may be the same as or different from each other;
b is an integer of 1 to 3, and when it is an integer of 2 or more, each R ₂ may be the same as or different from each other;
c and d are each independently an integer of 1 to 5, and when c or d is an integer of 2 or greater, each R ₃ and each R ₄ may be the same as or different from each other;
The heteroaryl (ene) and heterocycloalkyl each independently include one or more heteroatoms selected from B, N, O, S, Si and P. The method of claim 1, wherein L ₁ , L ₂ and R ₁ to R ₁₂ are substituted alkyl, substituted cycloalkyl, substituted cycloalkenyl, substituted heterocycloalkyl, substituted aryl(ene), substituted heteroaryl(ene), and The substituents of the substituted monocyclic or polycyclic alicyclic or aromatic ring 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 members) ) heterocycloalkyl, (C6-C30) aryloxy, (C6-C30) arylthio, (3-30 membered) heteroaryl unsubstituted or substituted with (C6-C30) aryl, (3-30 membered) heteroaryl Substituted or unsubstituted with (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)alkylboro One selected from the group consisting of nyl, (C1-C30)alkyl(C6-C30)arylboronyl, (C6-C30)ar(C1-C30)alkyl and (C1-C30)alkyl(C6-C30)aryl The above organic electroluminescent compound. The organic electroluminescent compound according to claim 1, wherein the compound of Formula 1 is represented by one of Formulas 2 and 3 below.
[Formula 2]

[Formula 3]

In Formulas 2 and 3,
Ar ₁ , Ar ₂ , L ₁ , L ₂ , X, R ₁ to R ₄ and a to d are as defined in claim 1. delete According to claim 1, L ₁ and L ₂ are each independently a single bond or a substituted or unsubstituted (C6-C12) arylene;
X is O, S, CR ₅ R ₆ or NR ₇ ;
R ₁ to R ₇ are each independently hydrogen, substituted or unsubstituted (C1-C6)alkyl, or substituted or unsubstituted (C6-C12)aryl, an organic electroluminescent compound. According to claim 1, L ₁ and L ₂ are each independently a single bond or unsubstituted (C6-C12) arylene;
X is O, S, CR ₅ R ₆ or NR ₇ ;
R ₁ to R ₇ are each independently hydrogen, unsubstituted (C1-C6)alkyl, or unsubstituted (C6-C12)aryl, an organic electroluminescent compound. The organic electroluminescent compound according to claim 1, wherein the compound represented by Formula 1 is selected from the following compounds.

An organic electroluminescent device comprising the organic electroluminescent compound of claim 1.