KR20140071944A - Organic Electroluminescence Compounds and Organic Electroluminescence Device Comprising the Same - Google Patents

Abstract

The present invention relates to an organic electroluminescent compound and an organic electroluminescent device including the same. The organic electroluminescent device with improved driving lifetime and improved current efficiency and power efficiency due to low drive voltage can be manufactured using the organic electroluminescent compound of the present invention.

Description

TECHNICAL FIELD [0001] The present invention relates to an organic electroluminescent compound and an organic electroluminescent device including the organic electroluminescent compound.

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

Among the display elements, electroluminescence devices (EL devices) are self-luminous display devices having a wide viewing angle, excellent contrast, and fast response speed. In 1987, Eastman Kodak Company developed an organic EL device using an aromatic diamine and an aluminum complex having low molecular weight as a light emitting layer forming material [Appl. Phys. Lett. 51, 913, 1987].

The most important factor determining the luminous efficiency in an organic electroluminescent device is a light emitting material. Fluorescent materials have been widely used as luminescent materials to date, but the development of phosphorescent materials has been widely studied in that phosphorescent materials can improve luminous efficiency up to 4 times the theoretical efficiency of phosphorescent materials in terms of the mechanism of electroluminescence . Until now, an iridium (III) complex series has been widely known as a phosphorescent material. Each RGB has bis (2- (2'-benzothienyl) -pyridinate-N, C-3 ') iridium (acetylacetonate ) [(acac) Ir (btp ) 2], tris (2-phenylpyridine) iridium [Ir (ppy) _3] and bis (4,6-difluorophenyl pyridinyl Nei Sat -N, C2) avoid collision Ney And materials such as tolidium (Firpic) are known.

In the prior art, 4,4'-N, N'-dicarbazole-biphenyl (CBP) is the most widely known phosphorescent host material. In recent years, Pioneer et al. Of Japan have been using bathocuproine (BCP) and aluminum (III) bis (2-methyl-8-quinolinate) (4-phenyl phenolate) Balq) as a host material and developed a high-performance organic electroluminescent device.

However, existing materials are advantageous in terms of luminescent properties, but they have the following disadvantages: (1) the material is changed when the glass transition temperature is low and the thermal stability is low and the material is subjected to a high temperature deposition process under vacuum. (2) In the organic electroluminescent device, the power efficiency is in the relation of [(? / Voltage) x current efficiency], so that the power efficiency is inversely proportional to the voltage. In the organic electroluminescent device using the phosphorescent host material, The current efficiency (cd / A) is higher than that of the light emitting device, but the driving voltage is also very high, so there is no great advantage in terms of power efficiency (lm / w). (3) In addition, when used in an organic electroluminescent device, it is unsatisfactory in terms of operating life, and luminous efficiency is still required to be improved.

Korean Patent Laid-Open Nos. 10-2011-0013220, 10-2005-0100694, and 10-2007-0073868 disclose that heteroaryl containing aryl or nitrogen at the nitrogen position of the benzocarbazole or dibenzocarbazole skeleton This substituted compound is disclosed as a compound for an organic electroluminescence device.

However, the above documents do not disclose specifically an organic electroluminescent compound having a structure in which phenyl is substituted for the carbon position of benzocarbazole, and heteroaryl containing nitrogen is substituted at the nitrogen position.

Korean Patent Publication KR10-2011-0013220 A (Published on February, 2011) Korean Patent Publication KR10-2005-0100694 A (published on October 19, 2005) Korean Patent Publication No. KR10-2007-0073868 A (published on July 10, 2007)

An object of the present invention is to provide an organic electroluminescent compound capable of producing an organic electroluminescent device having an excellent driving lifetime and a low driving voltage, thereby improving current efficiency and power efficiency.

As a result of intensive studies to solve the above technical problems, the present inventors have found that an organic electroluminescent compound represented by the following general formula (1) achieves the above-mentioned object and completed the present invention.

[Chemical Formula 1]

In Formula 1,

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

Ar ₁ to Ar ₄ each independently represent hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C6- A substituted or unsubstituted (C1-C30) alkylamino group, a substituted or unsubstituted (C6-C30) arylamino group, or a substituted or unsubstituted (C1-C30) alkyl (C6-C30) arylamino group; May be connected to the adjacent substituent to form a (3-30 membered) monocyclic or polycyclic substituted or unsubstituted alicyclic or aromatic ring, and the carbon atom of the alicyclic or aromatic ring formed is selected from nitrogen, oxygen and sulfur Lt; / RTI > may be replaced by one or more heteroatoms;

A ring represents substituted or unsubstituted (C6-C30) aryl, or substituted or unsubstituted (3-30 membered heteroaryl;

X ₁ is -N- or -CR ₁ -;

X ₂ is -N- or -CR ₂ -;

X ₃ is -N- or -CR ₃ -;

When X ₁ to X ₃ are each -CR ₁ -, -CR ₂ - and -CR ₃ -, ring A is nitrogen-containing (3-30 membered heteroaryl);

Wherein R ₁ to R ₃ are each independently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted (C 1 -C 30) alkyl, substituted or unsubstituted (C 6 -C 30) aryl, substituted or unsubstituted (C 13 -C 30) Or a substituted or unsubstituted (3-30 membered) heteroaryl group;

l is 0 or 1, m is an integer from 0 to 5, n is an integer from 0 to 2, and when m or n is an integer of 2 or more, each Ar ₁ or each Ar ₂ may be the same or different;

The heteroaryl comprises at least one heteroatom selected from B, N, O, S, P (= O), Si and P.

The organic electroluminescent compound according to the present invention has an advantage of being able to manufacture an organic electroluminescent device having an excellent driving lifetime and an improved current efficiency and power efficiency due to a low driving voltage.

The present invention will now be described in more detail, but this 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 same.

The organic electroluminescent compound represented by Formula 1 of the present invention will be described in more detail as follows.

Specific examples of the "alkyl" described in the present invention include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl. Specific examples of the "alkenyl" herein include vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 2-methylbut-2-enyl and the like. Examples of "alkynyl" herein include ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-methylpent-2- Examples of "cycloalkyl" herein include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like. The term "(5-7 membered) heterocycloalkyl" as used herein means an aromatic heterocycle having 5 to 7 ring skeletal atoms and at least one heteroatom selected from the group consisting of B, N, O, S, P (= O) Preferably one or more heteroatoms selected from O, S and N, and includes, for example, tetrahydrofuran, pyrrolidine, thiolane, tetrahydropyran and the like. Means a single ring or fused ring radical derived from an aromatic hydrocarbon and includes, for example, phenyl, biphenyl, terphenyl, naphthyl, binaphthyl, phenylnaphthyl, naphthylphenyl, Anthracenyl, indenyl, triphenylenyl, pyrenyl, tetracenyl, perylenyl, and cricenyl < RTI ID = 0.0 > , Naphthacenyl, fluoranthenyl and the like. The term "(3-30) heteroaryl (phenylene)" used herein refers to a heteroaryl group having 3 to 30 ring skeletal atoms and one or more heteroatoms selected from the group consisting of B, N, O, S, P Quot; means an aryl group containing an atom. The number of heteroatoms is preferably 1 to 4, and may be a monocyclic ring system or a fused ring system condensed with at least one benzene ring, and may be partially saturated. In addition, the heteroaryl (phenylene) also includes a heteroaryl group in which at least one heteroaryl or aryl group is linked to a heteroaryl group by a single bond. Examples of such heteroaryls include furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl , Monocyclic heteroaryl such as triazolyl, tetrazolyl, furanzyl, pyridyl, pyrazinyl, pyrimidinyl and pyridazinyl, benzofuranyl, benzothiophenyl, isobenzofuranyl, dibenzofuranyl, di Benzoimidazolyl, benzothiazolyl, benzothiazolyl, benzoisothiazolyl, benzooxazolyl, isoindolyl, indolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, Fused heterocyclic heteroaryl such as norbornyl, quinazolinyl, quinoxalinyl, carbazolyl, phenoxaphyl, phenanthridinyl, benzodioxolyl and the like. As used herein, "halogen" includes F, Cl, Br, and I atoms.

Also, in the phrase "substituted or unsubstituted" described in the present invention, "substituted" means that a hydrogen atom is replaced with another atom or another functional group (ie, a substituent) in a certain functional group. Substituted alkyl, substituted aryl (phenylene), substituted heteroaryl (phenylene), substituted alkylamino, substituted arylamino and substituted alkylarylamino in R ₁ , Ar ₁ to Ar ₄ , ring A and R ₁ to R ₃ in Formula 1 (C6-C30) aryl, (C6-C30) aryl optionally substituted by deuterium, halogen, halogen substituted or unsubstituted (C1-C30) (C3-C30) cycloalkyl, (5-7 membered) heterocycloalkyl, tri (C1-C30) alkylsilyl, tri (C1-C30) alkylsilyl, (C2-C30) alkenyl, (C2-C30) alkynyl, cyano, di (C1- (C1-C30) alkylamino, di (C6-C30) arylamino, (C1- (C6-C30) aryl (C1-C30) alkyl, (C6-C30) arylcarbonyl, Means that at least one selected from the group, and; Are each independently at least one member selected from the group consisting of (C1-C6) alkyl and (C6-C21) aryl.

The compound represented by the formula (1) is preferably a compound represented by the following formula (1a) or (1b).

[Formula 1a]

[Chemical Formula 1b]

In the above formulas (1a) and (1b), L ₁ , Ar ₁ to Ar ₄ , A ring, X ₁ , X ₂ , X ₃ , R ₂ , R ₃ , l, m and n are as defined in the above formula (1).

In one embodiment of the present invention, L < ₁ > is a single bond, a substituted or unsubstituted (C6-C30) arylene group, or a substituted or unsubstituted (3-30 membered) heteroarylene group; Preferably a single bond, or a substituted or unsubstituted (C6-C21) arylene group; More preferably a single bond or an unsubstituted (C6-C12) arylene group; Even more preferably a single bond or phenylene.

The Ar ₁ To Ar ₄ are each independently hydrogen, deuterium, a halogen, a cyano group, a substituted or unsubstituted (C1-C30) alkyl group, a substituted or unsubstituted (C6-C30) aryl group, a substituted or unsubstituted (3-30 membered) heterocycloalkyl (C6-C30) arylamino group, a substituted or unsubstituted (C1-C30) alkylamino group, a substituted or unsubstituted (C6-C30) arylamino group, or a substituted or unsubstituted (3-30 membered) monovalent or polycyclic substituted or unsubstituted alicyclic or aromatic ring; (C1-C6) alkyl group, a substituted or unsubstituted (C6-C21) aryl group, or an unsubstituted (5-21 member) heteroaryl group. More preferably Ar ₁ , Ar ₃ and Ar ₄ are each independently hydrogen or an unsubstituted (C6-C12) aryl group; Ar < ₂ > is hydrogen; (C1-C4) alkyl group; (C6-C18) aryl group substituted or unsubstituted with (C1-C4) alkyl; Or an unsubstituted (5-18 member) heteroaryl group. Even more preferably, Ar ₁ is hydrogen, phenyl or a naphthyl group; Wherein Ar ₂ is selected from the group consisting of hydrogen, (C 1 -C 4) alkyl, phenyl, naphthyl, dibenzofuranyl, dibenzothiophenyl, fluorenyl substituted by (C 1 -C 4) alkyl, Substituted benzofluorenyl and Ar < ₃ > is hydrogen; Ar ₄ is hydrogen or phenyl.

The ring A represents a substituted or unsubstituted (C6-C30) aryl, or a substituted or unsubstituted (3-30) heteroaryl, preferably a substituted or unsubstituted (C6-C21) (5 to 21 member) heteroaryl group, more preferably a (C6-C12) aryl group; Or a (5-15 member) heteroaryl group substituted or unsubstituted with (C6-C12) aryl, still more preferably phenyl; Biphenyl; Naphthyl; Quinolyl; Isoquinolyl; Naphthyridinyl; Phenanthrenyl; Phenanthridinyl; Benzoquinolyl; Benzoquinazolinyl; Benzoisoquinolyl; Phenanthrolinyl; Pyridyl; Pyrimidinyl; Or pyridyl substituted with phenyl.

X ₁ is -N- or -CR ₁ -; X ₂ is -N- or -CR ₂ -; X ₃ is -N- or -CR ₃ -. When X ₁ to X ₃ are each -CR ₁ -, -CR ₂ - and -CR ₃ -, ring A is a nitrogen containing (3-30 membered heteroaryl, preferably nitrogen containing (5-21 member) Heteroaryl, more preferably nitrogen-containing (5-15 membered) heteroaryl.

Wherein R ₁ to R ₃ are each independently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted (C 1 -C 30) alkyl, substituted or unsubstituted (C 6 -C 30) aryl, substituted or unsubstituted (C 13 -C 30) (C6-C21) aryl group, a substituted or unsubstituted (C15-C25) spirofluorenyl group, a substituted or unsubstituted (C30-C25) heteroaryl group, Or a substituted or unsubstituted (5-21 member) heteroaryl group, more preferably hydrogen; (C6-C18) aryl group unsubstituted or substituted by (C1-C4) alkyl or (C6-C12) aryl; (C15-C25) spirofluorenyl group; Or a (5-15 member) heteroaryl group substituted or unsubstituted with (C6-C12) aryl, still more preferably hydrogen; Phenyl; Biphenyl; Terphenyl; Naphthyl; Naphthylphenyl; (C1-C4) alkyl; Fluorenyl; (Cl-C4) alkyl or fluorenyl substituted with phenyl; Spirobifluorenyl; Spiro [cyclopentane-1,9'-fluorene] yl; Spiro [cyclohexane-1,9'-fluorene] yl; Dibenzofuranyl; Dibenzothiophenyl; Or a carbazolyl substituted with phenyl. Specifically, R ₁ is hydrogen; R < ₂ > is hydrogen or phenyl; R ₃ can be hydrogen, phenyl, biphenyl, terphenyl, naphthyl, phenyl substituted with (C 1 -C 4) alkyl, dibenzofuranyl, dibenzothiophenyl, or carbazolyl substituted with phenyl.

Wherein l is 0 or 1; M is an integer of 0 to 5, preferably an integer of 0 to 2; N is an integer from 0 to 2, preferably 0 or 1; When m or n is an integer of 2 or more, each Ar ₁ or each Ar ₂ may be the same or different.

According to one embodiment of the present invention, in Formula 1, L ₁ is a single bond or a substituted or unsubstituted (C6-C21) arylene group; The Ar ₁ To Ar ₄ are each independently hydrogen, unsubstituted (C1-C6) alkyl group, a substituted or unsubstituted (C6-C21) aryl group, or unsubstituted (5-21 W) may be an heteroaryl; Ring A represents a substituted or unsubstituted (C6-C21) aryl group, or a substituted or unsubstituted (5-21 membered heteroaryl group; X ₁ is -N- or -CR ₁ -; X ₂ is -N- or -CR ₂ -; X ₃ is -N- or -CR ₃ -; When X ₁ to X ₃ are each -CR ₁ -, -CR ₂ - and -CR ₃ -, the ring A is nitrogen-containing (5-21 membered heteroaryl); Wherein R ₁ to R ₃ are each independently hydrogen, a substituted or unsubstituted (C6-C21) aryl group, a substituted or unsubstituted (C15-C25) spirofluorenyl group, or a substituted or unsubstituted An aryl group; Wherein l is 0 or 1; M is an integer from 0 to 2; N is 0 or 1; When m is 2, each Ar ₂ may be the same or different.

According to another aspect of the present invention, in Formula 1, wherein L ₁ is a single bond or unsubstituted (C6-C12) aryl group; Ar ₁ , Ar ₃ and Ar ₄ are each independently hydrogen or an unsubstituted (C6-C12) aryl group; Ar < ₂ > is hydrogen; (C1-C4) alkyl group; (C6-C18) aryl group substituted or unsubstituted with (C1-C4) alkyl; Or an unsubstituted (5-18 member) heteroaryl group; Ring A is a (C6-C12) aryl group or a (5-15 membered) heteroaryl group substituted or unsubstituted with (C6-C12) aryl; X ₁ is -N- or -CR ₁ -; X ₂ is -N- or -CR ₂ -; X ₃ is -N- or -CR ₃ -; When X ₁ to X ₃ are each -CR ₁ -, -CR ₂ - and -CR ₃ -, the ring A is a nitrogen-containing (5-15 member) heteroaryl; R ₁ to R ₃ are each independently hydrogen; (C6-C18) aryl group unsubstituted or substituted by (C1-C4) alkyl or (C6-C12) aryl; (C15-C25) spirofluorenyl group; Or a (5-15 member) heteroaryl group substituted or unsubstituted with (C6-C12) aryl; Wherein l is 0 or 1; M is an integer from 0 to 2; N is 0 or 1; When m is 2, each Ar ₂ may be the same or different.

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

The organic electroluminescent compound according to the present invention can be prepared by a synthesis method known to a person skilled in the art and can be prepared, for example, as shown in the following reaction formula.

[Reaction Scheme 1]

[Reaction Scheme 2]

The present invention also provides an organic electroluminescent material comprising an organic electroluminescent compound of Formula 1 and an organic electroluminescent device comprising the same.

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

An organic electroluminescent device according to the present invention includes a first electrode; A second electrode; And at least one organic material layer interposed between the first electrode and the second electrode, and the organic material layer may include at least one organic electroluminescent compound represented by 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 may further include one or more layers selected from the group consisting of 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 layer may include a light emitting layer, and the organic electroluminescent compound of Formula 1 may be used as a host material in the light emitting layer.

The phosphorescent dopant for an organic electroluminescent device used together with the host material according to the present invention is typically represented by the following formula (2).

(2)

M ^One L ¹⁰¹ L ¹⁰² L ¹⁰³

In Formula 2,

Wherein M ¹ is selected from the group consisting of Ir, Pt, Pd and Os,

Ligands L ¹⁰¹ , L ¹⁰² and L ¹⁰³ are independently selected from the following structures,

R ₂₀₁ to R ₂₀₃ independently represent hydrogen, deuterium, (C 1 -C 30) alkyl in which the halogen is optionally substituted (C 1 -C 30) alkyl, (C 6 -C 30) aryl or halogen in which the (C 1 -C 30) alkyl is optionally substituted;

R ₂₀₄ to R ₂₁₉ are each independently selected from the group consisting of hydrogen, deuterium, substituted or unsubstituted (C 1 -C 30) alkyl, substituted or unsubstituted (C 1 -C 30) alkoxy, substituted or unsubstituted (C 3 -C 30) (C6-C30) aryl, substituted or unsubstituted mono- or di- (C1-C30) alkylamino, substituted or unsubstituted mono- or di- ) arylamino, SF _5, a substituted or unsubstituted tree (C1-C30) alkylsilyl, substituted or unsubstituted di (C1-C30) alkyl (C6-C30) arylsilyl, substituted or unsubstituted tree (C6-C30) aryl Silyl, cyano, or halogen; Together with the adjacent substituents, form a single or multiple (C5-C30) alicyclic or aromatic ring;

R ₂₂₀ to R ₂₂₃ independently of one another are hydrogen, deuterium, (C 1 -C 30) alkyl in which the halogen is optionally substituted (C 1 -C 30) alkyl or (C 6 -C 30) aryl in which the (C 1 -C 30) alkyl is optionally substituted;

R ₂₂₄ and R ₂₂₅ independently represent hydrogen, deuterium, substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C6-C30) aryl or halogen, R ₂₂₄ and R ₂₂₅ is a single part together with the adjacent substituents Or a polycyclic (C5-C30) alicyclic or aromatic ring;

R ₂₂₆ is substituted or unsubstituted (C 1 -C 30) alkyl, substituted or unsubstituted (C 6 -C 30) aryl, substituted or unsubstituted (5-30 membered) heteroaryl or halogen;

R ₂₂₇ to R ₂₂₉ are independently of each other hydrogen, deuterium, substituted or unsubstituted (C 1 -C 30) alkyl, substituted or unsubstituted (C 6 -C 30) aryl or halogen;

R ₂₃₀ is hydrogen, substituted or unsubstituted (C 1 -C 30) alkyl, or substituted or unsubstituted (C 3 -C 30) cycloalkyl;

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 ₂₃₀ may be the same or different from each other;

,

또는

이며, R₂₃₁ 내지 R₂₄₂는 서로 독립적으로 수소, 중수소, 할로겐이 치환되거나 치환되지 않은 (C1-C30)알킬, (C1-C30)알콕시, 할로겐, 치환 또는 비치환 (C6-C30)아릴, 시아노, 치환 또는 비치환 (C5-C30)시클로알킬이거나, 인접한 치환체와 알킬렌 또는 알케닐렌으로 연결되어 스피로 고리 또는 융합고리를 형성할 수 있거나, R₂₀₇ 또는 R₂₀₈과 알킬렌 또는 알케닐렌으로 연결되어 포화 또는 불포화의 융합고리를 형성할 수 있다.Q is

,

or

R ₂₃₁ to R ₂₄₂ are independently selected from the group consisting of hydrogen, deuterium, (C 1 -C 30) alkyl optionally substituted with halogen, (C 1 -C 30) alkoxy, halogen, substituted or unsubstituted (C 6 -C 30) (C5-C30) cycloalkyl, or may be connected to an adjacent substituent with an alkylene or alkenylene to form a spiro ring or a fused ring, or R < _{207 >} or R & To form a saturated or unsaturated fused ring.

Specifically, it is preferable to use the following compound as the dopant compound of the above formula (2).

The organic electroluminescent device of the present invention includes the organic electroluminescent compound of Formula 1, and at the same time, may include one or more compounds selected from the group consisting of an arylamine-based compound and a styrylarylamine-based compound.

Further, in the organic electroluminescent device of the present invention, in addition to the organic electroluminescent compound of Formula 1, an organic electroluminescent compound of the group 1, 2, 4, 5 period transition metal, lanthanide series and d- The organic compound layer may further include at least one metal or complex compound selected from the group consisting of a light emitting layer and a charge generating layer.

In addition, the organic material layer may include at least one organic light emitting layer including a blue, red, or green light emitting compound in addition to the organic electroluminescent compound to form an organic electroluminescent device emitting white light.

In the organic electroluminescent device of the present invention, one layer selected from a chalcogenide layer, a metal halide layer and a metal oxide layer (hereinafter referred to as " surface layer ") is formed on the inner surface of at least one of the pair of electrodes, Or more. Concretely, it is preferable to dispose a halogenated metal layer or a metal oxide layer on the surface of the anode on the side of the light emitting medium layer and on the surface of the cathode on the side of the light emitting medium layer, with a chalcogenide (including oxide) layer of a metal of silicon and aluminum Do. Thus, stabilization of the drive can be obtained. Preferable examples of the chalcogenide include SiO _X (1? _X ? 2), AlO _x (1? _X ? 1.5), SiON or SiAlON. Preferred examples of the halogenated metal include LiF, MgF ₂ , CaF ₂ , Rare-earth metals, etc. Preferred examples of the 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, a mixed region of the electron transfer compound and the reducing dopant or a mixed region of the hole transport compound and the oxidative dopant is disposed on at least one surface of the pair of electrodes thus fabricated desirable. 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 and becomes a cation, it becomes easy to inject and transport holes from the mixed region into the light emitting medium. Preferred oxidizing dopants include various Lewis acids and acceptor compounds, and preferred reducing dopants include alkali metals, alkali metal compounds, alkaline earth metals, rare earth metals, and mixtures thereof. Also, a white organic light emitting device having two or more light emitting layers can be manufactured using a reducing dopant layer as a charge generating layer.

The formation of each layer of the organic electroluminescent device of the present invention can be performed by a dry film formation method such as vacuum deposition, sputtering, plasma or ion plating, or a wet film formation method such as spin coating, dipping or flow coating .

In the case of the wet film formation method, a thin film is formed by dissolving or dispersing a material forming each layer in an appropriate solvent such as ethanol, chloroform, tetrahydrofuran, dioxane, etc., and any solvent may be used.

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

[ Example ] Preparation of the present compound

[ Example  1] Preparation of Compound C-12

Compound 2 [(4- Phenyl naphthalene -1 day) Boronic acid ]

1-Bromo-4-phenylnaphthalene (Compound 1) (50 g, 176 mmol) was dissolved in 1 L of anhydrous tetrahydrofuran (THF) and stirred at -78 ° C. To this was added n-BuLi (2.5 M, 132 mL in hexane) slowly dropwise. The reaction was stirred at room temperature for 1 hour. The reaction was cooled again to -78 ° C and then triisopropylborate (61 mL, 264 mmol) was slowly added dropwise. The reaction product was stirred at room temperature for 3 hours. After the reaction was completed, the organic layer was extracted with ethyl acetate, and the residue was dried with magnesium sulfate, and then dried and solidified with hexane to obtain Compound 2 (30 g, 68%).

Compound 4 [1- (4- Bromo -2- Nitrophenyl )-4- Phenyl naphthalene ]

To the flask was added 1,4-dibromo 2-nitrobenzene (Compound 3) (14.2 g, 50.38 mmol) and Compound 2 (15 g, 60.46 mmol) and tetrakis (triphenylphosphine) palladium (0) PPh ₃ ) ₄ ) (1.7 g, 1.51 mmol) was dissolved in 125 mL of 2 M Na ₂ CO ₃ , 250 mL of toluene and 125 mL of ethanol, and the mixture was refluxed at 120 ° C. for 5 hours. After the reaction was completed, the organic layer was extracted with ethyl acetate, and the residue was dried with magnesium sulfate, dried and separated into a column to obtain Compound 4 (13 g, 64%).

Compound 5 [1- (3-Nitro [1,1'-biphenyl] -4-yl) -4- Phenyl naphthalene ]

Compound 4 (13 g, 33.87 mmol) and phenylboronic acid (3.9 g, 32.26 mmol) were synthesized by the method of Compound 4 to obtain Compound 5 (12 g, 98%).

Compound 7 [5,9- Diphenyl -7H- Benzo [c] carbazole ]

Compound 5 (12 g, 32 mmol) was dissolved in 130 mL of triethylphosphate and refluxed at 150 ° C for 6 hours. After the reaction was completed, the reaction mixture was distilled and then triturated with methanol to obtain Compound 7 (6.8 g, 62%).

compound C-12  [5,9- Diphenyl -7- (4- Phenylquinazoline Yl) -7H- Benzo [c] carbazole ]

(4 g, 10.83 mmol) and compound 7 (3.2 g, 12.99 mmol) were dissolved in 55 mL of dimethylformamide (DMF) and NaH (0.4 g, 16.4 mmol, 60% in mineral oil). The mixture was stirred at room temperature for 12 hours, and methanol and distilled water were added thereto. The resulting solid was filtered off under reduced pressure and subjected to column separation to obtain a compound C-12 (2 g, 33%).

UV: 384 nm, PL: 515 nm, melting point: 178 DEG C

MS / EIMS measurement 573.7; Calculated 573.23

[ Example  2-24]

The following compounds were prepared in a manner similar to that of Example 1,

[ Example  25] Preparation of Compound C-56

compound C-56 [5,9- Diphenyl -7- (2- Phenylquinoline -7-yl) -7H- Benzo [c] carbazole ]

To a solution of 7-chloro-2-phenylquinoline (3 g, 11.91 mmol) and compound 7 (4 g, 10.83 mmol) in 60 mL of dimethylformamide (DMF) was added NaH (0.4 g, 16.4 mmol, %). The mixture was stirred at room temperature for 12 hours, and methanol and distilled water were added thereto. The resulting solid was filtered under reduced pressure and subjected to column separation to obtain a compound C-56 (2 g, 33%).

Table 1 below shows the physical properties of the compounds prepared in Examples 1 to 25.

[ Example  26] Preparation of Compound C-66

Preparation of Compound 2-5

Compound 2-5 (12 g, 76%) was obtained in the same manner as in the preparation of Compound 7 of Example 1 above.

Preparation of Compound 2-6

Compound 12 (12 g), 1-bromo-4-iodobenzene (8 g), CuI (500 mg), ethylenediamine (EDA) (4 mL) and toluene (100 mL) were added to a 250 mL round- do. After the reaction is completed, the reaction mixture is cooled to room temperature and then worked up, followed by column chromatography to obtain Compound 2-6 (14 g, 87%).

Preparation of compound 2-7

(14 g), B ₂ (Pin) ₂ (15 g), bis (triphenylphosphine) palladium (II) dichloride (PdCl ₂ (PPh ₃ ) ₂ ) (1.2 mg), potassium Acetate (KOAc ₂ ) (10 g) and 1,4-dioxane (100 mL) were added, and the mixture was refluxed and stirred for 13 hours. After completion of the reaction, the reaction mixture was cooled to room temperature and then worked up and subjected to column chromatography to obtain Compound 2-7 (15 g, 82%).

Preparation of Compound 2-9

500mL compound 2-8 (50g) To a round flask, phenylboronic acid _{(26g), Pd (PPh 3} ) 4 (3g), K 2 CO 3 (26g), ethanol (EtOH) (50mL), distilled water (100mL), Toluene (400 mL) was added, and the mixture was refluxed and stirred for 4 hours. When the reaction is completed, the reaction mixture is cooled to room temperature and then worked up and subjected to column chromatography to obtain Compound 2-9 (25 g).

Preparation of Compound C-66

Compound 2-7 in 250mL round bottom flask (11g), compound 2-9 (4g), Pd (PPh 3) 4 (1g), K 2 CO 3 (5g), EtOH (30mL), distilled water (60mL), and toluene (200 mL) were added, and the mixture was refluxed with stirring for 20 hours. After completion of the reaction, the reaction mixture was cooled to room temperature and then worked up and subjected to column chromatography to obtain Compound C-66 (1.5 g).

[ Example  27] Preparation of Compound C-65

Compound 3-1 was prepared in the same manner as in the production of Compound 2 to 7 of Example 1 except that 1-bromo-4-phenylnaphthalene (Compound 1) was replaced by 1-bromonaphthalene, To a solution of 6.8 g (28.41 mmol) of the compound 2-9, 10 g (34.09 mmol) of the compound 3-1, 4.7 g (34.09 mmol) of K ₂ CO ₃ and 4-dimethylaminopyridine (2.1 g, 17.05 mmol) The mixture was stirred at the reflux time. The mixture was cooled to room temperature and distilled water was added thereto. Extracted with methylene chloride (MC) and dried over magnesium sulfate. The mixture was distilled under reduced pressure and recrystallized from ethyl acetate (EA) and methanol to obtain a compound C-65 (3.5 g, 22%).

[device Manufacturing example  1] The organic Field  Using a luminescent compound OLED  Device fabrication

An OLED device having a structure using the light emitting material of the present invention was fabricated. First, a transparent electrode ITO thin film (15? /?) Obtained from a glass for OLED (manufactured by Samsung Corning) was ultrasonically cleaned using trichlorethylene, acetone, ethanol and distilled water sequentially and stored in isopropanol Respectively. Next, an ITO substrate was mounted on a substrate holder of a vacuum deposition apparatus, and N ¹ , N ^{1 '} - ([1,1'-biphenyl] -4,4'-diyl) bis ¹ - (naphthalene- ¹ -yl) -N ⁴ , N ⁴ -diphenylbenzene-1,4-diamine) was added and the chamber was evacuated until the degree of vacuum reached 10 ^-6 torr. And evaporated to deposit a 60 nm thick hole injection layer on the ITO substrate. Subsequently, N, N'-di (4-biphenyl) -N, N'-di (4-biphenyl) -4,4'- diaminobiphenyl was added to another cell in the vacuum vapor- And evaporated to deposit a hole transport layer having a thickness of 20 nm on the hole injection layer. A hole injecting layer and a hole transporting layer were formed, and then a light emitting layer was deposited thereon as follows. The compound C-12 of the present invention was added as a host to one cell in a vacuum deposition apparatus and the compound D-7 as a dopant was introduced into another cell. Then, the two substances were evaporated at different rates to prepare a dopant A 30 nm thick light emitting layer was deposited on the hole transport layer by doping the dopant in an amount of 4 wt%. Then, on one side of the luminescent layer as an electron transporting layer was added a solution of 2- (4- (9,10-di (naphthalen-2-yl) anthracen- And lithium quinolate was added to each of the other cells. Then, the two materials were evaporated at the same rate and doped in an amount of 50 wt% each to deposit an electron transport layer of 30 nm. Next, lithium quinolate was deposited to a thickness of 2 nm as an electron injecting layer, and an Al cathode was deposited to a thickness of 150 nm using another vacuum vapor deposition apparatus to fabricate an OLED device. Each compound was purified by vacuum sublimation under 10 ^-6 torr.

As a result, a current of 5.9 mA / cm ² flowed at a voltage of 3.4 V, and red emission of 980 cd / m ² was confirmed. At a luminance of 5000 nits, the time required for the emission to drop to 90% was more than 160 hours.

[device Manufacturing example  2 to 27] Using the organic luminescent compound according to the present invention OLED  Device fabrication

OLED devices were fabricated in the same manner as in Example 1 except that the host and the dopant described in [Table 2] were used.

[ Comparative Example  1] Conventional organic Field  Using a luminescent compound OLED  Luminescent characteristics of device

Emitting layer of 30 nm thickness was deposited on the hole transport layer using 4,4'-N, N'-dicarbazole-biphenyl (CBP) as the luminescent material and aluminum (III) bis 2-methyl-8-quinolinato) 4-phenylphenolate was deposited to a thickness of 10 nm, and Compound D-11 was used as the dopant.

As a result, a current of 20.0 mA / cm ² was passed at a voltage of 8.2 V, and red luminescence of 1000 cd / m ² was confirmed. At a luminance of 5000 nits, the time taken for the emission to drop to 90% was more than 10 hours.

The results of the above Examples and Comparative Examples are summarized in the following [Table 2].

The organic electroluminescent compound according to the present invention has an advantage of being able to produce an organic electroluminescent device having an excellent driving life and a low driving voltage and thus improving current efficiency and power efficiency. Layer. However, when the present compounds are used, there is an advantage that a hole blocking layer is not needed.

Claims (7)

An organic electroluminescent compound represented by the following formula (1).
[Chemical Formula 1]

In Formula 1,
L ₁ is a single bond, a substituted or unsubstituted (C6-C30) arylene group, or a substituted or unsubstituted (3-30 membered) heteroarylene group;
Ar ₁ to Ar ₄ each independently represent hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C6- A substituted or unsubstituted (C1-C30) alkylamino group, a substituted or unsubstituted (C6-C30) arylamino group, or a substituted or unsubstituted (C1-C30) alkyl (C6-C30) arylamino group; May be connected to the adjacent substituent to form a (3-30 membered) monocyclic or polycyclic substituted or unsubstituted alicyclic or aromatic ring, and the carbon atom of the alicyclic or aromatic ring formed is selected from nitrogen, oxygen and sulfur Lt; / RTI > may be replaced by one or more heteroatoms;
A ring represents substituted or unsubstituted (C6-C30) aryl, or substituted or unsubstituted (3-30 membered heteroaryl;
X ₁ is -N- or -CR ₁ -;
X ₂ is -N- or -CR ₂ -;
X ₃ is -N- or -CR ₃ -;
When X ₁ to X ₃ are each -CR ₁ -, -CR ₂ - and -CR ₃ -, ring A is nitrogen-containing (3-30 membered heteroaryl);
Wherein R ₁ to R ₃ are each independently selected from the group consisting of hydrogen, deuterium, halogen, substituted or unsubstituted (C 1 -C 30) alkyl, substituted or unsubstituted (C 6 -C 30) aryl, substituted or unsubstituted (C 13 -C 30) Or a substituted or unsubstituted (3-30 membered) heteroaryl group;
l is 0 or 1, m is an integer from 0 to 5, n is an integer from 0 to 2, and when m or n is an integer of 2 or more, each Ar ₁ or each Ar ₂ may be the same or different;
The heteroaryl comprises at least one heteroatom selected from B, N, O, S, P (= O), Si and P. The organic electroluminescent compound according to claim 1, wherein the compound represented by Formula 1 is a compound represented by Formula 1a or 1b.
[Formula 1a]

[Chemical Formula 1b]

In the general formulas (1a) and (1b), L ₁ , Ar ₁ to Ar ₄ , A ring, X ₁ , X ₂ , X ₃ , R ₂ , R ₃ , l, m and n are the same as defined in the above item 1. A compound according to claim 1, wherein said L ₁ , Ar ₁ to Ar ₄ , ring A and R ₁ to R ₃ are substituted alkyl, substituted aryl (phenylene), substituted heteroaryl (C6-C30) aryl, (C6-C30) aryl which is unsubstituted or substituted by halogen, halogen, (C1-C30) alkyl, (C3-C30) cycloalkyl, (5-7 membered) heterocycloalkyl, tri (C1-C30) alkylsilyl, tri (C6-C30) arylsilyl, di (C2-C30) alkynyl, cyano, di (C1-C30) alkylsilyl, (C6-C30) arylamino, di (C6-C30) arylamino, di (C6-C30) arylamino, di (C1-C30) alkyl, (C6-C30) arylcarbonyl, (C6-C30) Ro And an organic electroluminescent compound. 2. The method of claim 1, wherein L ₁ is a single bond, or a substituted or unsubstituted (C6-C21) aryl group;
The Ar ₁ To Ar ₄ are each independently hydrogen, unsubstituted (C1-C6) alkyl group, a substituted or unsubstituted (C6-C21) aryl group, or unsubstituted (5-21 W) may be an heteroaryl;
The ring A represents a substituted or unsubstituted (C6-C21) aryl group, or a substituted or unsubstituted (5-21 member) heteroaryl group;
X ₁ is -N- or -CR ₁ -; X ₂ is -N- or -CR ₂ -; X ₃ is -N- or -CR ₃ -; When X ₁ to X ₃ are each -CR ₁ -, -CR ₂ - and -CR ₃ -, the ring A is nitrogen-containing (5-21 membered heteroaryl);
Wherein R ₁ to R ₃ are each independently hydrogen, a substituted or unsubstituted (C6-C21) aryl group, a substituted or unsubstituted (C15-C25) spirofluorenyl group, or a substituted or unsubstituted An aryl group;
Wherein l is 0 or 1; M is an integer from 0 to 2; N is 0 or 1; When m is 2, each Ar ₂ may be the same or different. 2. The method of claim 1, wherein L ₁ is a single bond or unsubstituted (C6-C12) aryl group;
Wherein Ar _1, Ar ₃ and Ar ₄ are each independently hydrogen or unsubstituted (C6-C12) aryl group wherein Ar ₂ is hydrogen; (C1-C4) alkyl group; (C6-C18) aryl group substituted or unsubstituted with (C1-C4) alkyl; Or an unsubstituted (5-18 member) heteroaryl group;
The A ring is a (C6-C12) aryl group or a (5-15 member) heteroaryl group substituted or unsubstituted with (C6-C12) aryl;
X ₁ is -N- or -CR ₁ -; X ₂ is -N- or -CR ₂ -; X ₃ is -N- or -CR ₃ -; When X ₁ to X ₃ are each -CR ₁ -, -CR ₂ - and -CR ₃ -, the ring A is a nitrogen-containing (5-15 member) heteroaryl;
R ₁ to R ₃ are each independently hydrogen; (C6-C18) aryl group unsubstituted or substituted by (C1-C4) alkyl or (C6-C12) aryl; (C15-C25) spirofluorenyl group; Or a (5-15 member) heteroaryl group substituted or unsubstituted with (C6-C12) aryl;
Wherein l is 0 or 1; M is an integer from 0 to 2; N is 0 or 1; When m is 2, each Ar ₂ may be the same or different. The organic electroluminescent compound according to claim 1, wherein the compound represented by Formula 1 is selected from the group consisting of the following compounds.

An organic electroluminescent device comprising the organic electroluminescent compound according to claim 1.