WO2007086552A1

WO2007086552A1 - Novel compound and organic electroluminescent device using same

Info

Publication number: WO2007086552A1
Application number: PCT/JP2007/051363
Authority: WO
Inventors: Yohei Ono; Manabu Uchida
Original assignee: Chisso Corporation
Priority date: 2006-01-30
Filing date: 2007-01-29
Publication date: 2007-08-02
Also published as: TW200738636A; JPWO2007086552A1; JP5119929B2

Abstract

Disclosed is a compound for an electron-transporting material and/or an electron injecting material, which contributes to decrease driving voltage of an organic EL device and to extend life of the organic EL device. Also disclosed is an organic EL device using such a compound. Specifically disclosed is a novel compound represented by the following formula (1). (1) In the formula, R1-R4 independently represent a hydrogen, an alkyl having 1-6 carbon atoms, a cycloalkyl having 3-6 carbon atoms, an optionally substituted aromatic ring having 6-18 carbon atoms or an optionally substituted heteroaromatic ring having 2-18 carbon atoms; R5-R8, R9, R10, R16 and R17 independently represent a hydrogen, an alkyl having 1-6 carbon atoms or a cycloalkyl having 3-6 carbon atoms; and R11-R15 and R18-R22 independently represent a hydrogen, an alkyl having 1-6 carbon atoms, a cycloalkyl having 3-6 carbon atoms, an optionally substituted aromatic ring having 6-18 carbon atoms or an optionally substituted heteroaromatic ring having 2-18 carbon atoms.

Description

Novel compound and organic electroluminescence device using the same

Technical field

[0001] The present invention relates to a novel compound having a 2,2'biviridine 5yl group, and an organic electroluminescence device using the same (hereinafter sometimes abbreviated as an organic EL device or simply a device).

Background art

[0002] In recent years, organic EL elements have attracted attention as next-generation full-color flat panel displays, and active research has been conducted. In order to promote the practical application of organic EL elements, it is essential to reduce the drive voltage and extend the life of the elements. The challenge is to improve blue elements, which have a long life. In order to achieve these goals, new electron transport materials have been developed, and organic EL devices using 2, 2, -bibilidyl compounds as electron transport materials are disclosed in Japanese National Publication of Heisei 11-5141 43 (Patent Literature 1) , Proceedings of the 10 International Workshop on Inorganic and Organic Electroluminescence, pages 241-244 (Non-Patent Document 1), and JP-A No. 2002-18093 (Patent Document 2). Patent Document 1 uses a compound having a triazine skeleton and lists 2,2′-bibilidyl as a substituent, but does not specifically disclose a 2,2 ′ bibilidyl compound. The 2,2′-bibilidyl compound described in Non-Patent Document 1 has a low glass transition temperature (hereinafter abbreviated as Tg) and is not practical. The 2,2′-bibilidyl compound described in Patent Document 2 can drive an organic EL device at a relatively low voltage, but further reduction of the voltage is desired for practical use. In addition, JP 2003-123983 A (Patent Document 3) discloses that an organic EL device can be formed at a low voltage by using a phantom-mouth phosphorus derivative or a 2,2′-bibilidyl compound as an electron transport material. It is described that it can be driven. However, the device characteristics (driving voltage, luminous efficiency, etc.) reported in the examples of this document are only relative values based on the comparative example (phenantorin phosphorus derivative), and the measured values are It is not described and it is unclear whether it has practical characteristics. And when the present inventors tested, the luminance retention rate However, it was difficult to put it to practical use.

Patent Document 1: Japanese Patent Publication No. 11 514143

Patent Document 2: Japanese Patent Laid-Open No. 2002-158093

Patent Document 3: Japanese Patent Laid-Open No. 2003-123983

Non-Patent Literature 1: Proceedings of the lOthlnternational Workshop on Inorganic and Organic Electroluminescence 241–244

Disclosure of the invention

Problems to be solved by the invention

[0003] The present invention has been made in view of the problems of such conventional techniques. It is an object of the present invention to provide an electron transport material that contributes to reducing the driving voltage and extending the lifetime of an organic EL element, and in particular to reducing the driving voltage and extending the lifetime of a blue element. Another object of the present invention is to provide an organic EL device using this electron transport material.

Means for solving the problem

[0004] As a result of intensive studies, the inventors of the present invention have used a compound in which a 2,2, -biviridine-5-yl group is bonded to the 9,10-position of anthracene for an electron transport layer of an organic EL device. We found that a blue light-emitting organic EL element that can be driven with high brightness, long life, and low voltage can be obtained.

The present invention has been completed based on this finding.

Said subject is solved by each item shown below.

[0005] [1] A compound having two 2,2 ′ biviridine 5yl groups represented by the following formula (1).

During the ceremony! ^ ¹ to! ^ ⁴ is independently hydrogen, alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, an optionally substituted aromatic ring system having 6 to 18 carbon atoms, or substituted. A heteroaromatic ring having 2 to 18 carbon atoms; R ^{5 to} R ⁸ , R ⁹ , R ¹⁰ , R ¹⁶ , and R ¹⁷ are independently hydrogen, alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons; and

R ^{U to} R ¹⁵ and R ^{18 to} R ²² are independently hydrogen, alkyl having 1 to 6 carbons, cycloalkyl having 3 to 6 carbons, an optionally substituted aromatic ring system having 6 to 18 carbons, Or substituted V or a heteroaromatic ring having 2 to 18 carbon atoms.

[2] The compound according to [1], wherein R ^{5 to} R ⁸ , R ⁹ , R ^1G , R ¹⁶ , and R ¹⁷ are hydrogen.

^{[3] 1 ^ ~1 ^ 4} , R U ~R 15 and R ¹⁸ to R ²² is hydrogen, cyclohexyl methyl, Echiru, propyl, isopropyl, butyl, isobutyl, t-butyl, hexyl, cyclohexane, phenyl, 1 The compound according to the above item [2], which is a group independently selected from naphthyl, 2-naphthyl, bipheryl, and terferyl.

[0006] [4] 1 ^ to 1 ^ ⁴ are hydrogen;

R ^{U to} R ¹⁵ and R ^{18 to} R ²² are hydrogen, methyl, ethynole, propyl, isopropyl, butynole, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1 naphthyl, 2-naphthyl, biphenyl, And the compound according to the above item [3], wherein the terfyl strength is also a group independently selected. ]! ^ ¹¹ to! ^ ¹⁵ and R ^{18 to} R ²² are independently selected from hydrogen, methyl, t-butyl, phenol, 1-naphthyl, 2-naphthyl, 4-biphenyl, and 3-biphenyl. The compound according to [4] above, which is a group.

[6] The compound according to [4] or [5] above, wherein two 2, 2, -biviridine-5-yl are the same.

[7] The compound according to [4] or [5] above, wherein R ^{U to} R ¹⁵ and R ^{18 to} R ²² are hydrogen.

[0007] [8]! ^ ~ R ⁴ is at least one of methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1 naphthyl, 2-naphthyl Rubi, biphenyl and terferyl forces independently selected groups with the remainder being hydrogen;

R ^{U to} R ¹⁵ and R ^{18 to} R ²² are hydrogen, methyl, ethynole, propyl, isopropyl, butynole, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1 naphthyl, 2-naphthyl, biphenyl, And the compound according to [3] above, wherein the terferyl power is also a group independently selected.

[Where R ¹ is methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1-naphthyl, 2-naphthyl, biphenylyl, and terphenyl- Yes;

R ^{2 to} R ⁴ are hydrogen;

R ^{U to} R ¹⁵ and R ^{18 to} R ²² are hydrogen, methyl, ethynole, propyl, isopropyl, butynole, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1 naphthyl, 2-naphthyl, biphenyl, And the compound according to the above item [3], wherein the terfyl strength is also a group independently selected.

[10] The above item [9], wherein! ^ Is a group in which methyl, t-butyl, phenol, 1-naphthyl, 2-naphthyl, 4-biphenyl, and 3-biphenyl are also selected. Compound.

[Eh! ^! ^ ~! ^^ ^ ~! The compound according to item [10], wherein ^ is a group independently selected from hydrogen, methyl, t-butyl, phenol, 1-naphthyl, 2-naphthyl, 4-biphenyl, and 3-biphenyl. .

[12] The compound according to [10] or [11] above, wherein the two 2,2,1-biviridine 5-yl groups are the same.

The compound according to [10] or [11] above, wherein []! ^ ¹¹ to! ^ ¹⁵ and R ^{18 to} R ²² are hydrogen. [0008] [14] R ¹ and R ² are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1 naphthyl, 2-naphthyl, biphenylyl, and terphe- Rill force is an independently selected group;

R ³ and R ⁴ are hydrogen;

R ^{U to} R ¹⁵ and R ^{18 to} R ²² are hydrogen, methyl, ethynole, propyl, isopropyl, butynole, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1 naphthyl, 2-naphthyl, biphenyl, And the compound according to the above [3], wherein the terferyl strength is also independently selected.

[15] The above item [14], wherein! ^ And R ² are groups independently selected from methyl, t-butyl, phenol, 1-naphthyl, 2-naphthyl, 4-biphenyl, and 3-biphenyl. Compound described in 1.

[! ^] ^ ¹¹ ~ ^ ¹⁵ and R ¹⁸ to R ²² are hydrogen, methyl, t-butyl, Hue -! Le, 1-naphthyl, 2-naphthyl, 4 Bifue - Lil, and 3 Bifue - selected Lil force independently The compound according to item [15], wherein the compound is a group.

[17] The compound according to [15] or [16] above, wherein the two 2,2,1 bibilyidine 5-yl groups are the same.

[18] R "to R ¹⁵ and R ¹⁸ to R ²² is hydrogen, the [15] or [16] compound of according to claim.

[0009] [l R ¹ and R ³ are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1 naphthyl, 2-naphthyl, biphenylyl, and terfenyl Force is an independently selected group;

R ² and R ⁴ are hydrogen;

R ^{U to} R ¹⁵ and R ^{18 to} R ²² are hydrogen, methyl, ethynole, propyl, isopropyl, butynole, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1 naphthyl, 2-naphtha The thiol, biphenyl-, and terferyl-powers are also independently selected groups, [

The compound according to item 3].

[20]! ^ And R ³ are groups in which methyl, t-butyl, phenol, 1-naphthyl, 2-naphthyl, 4-biphenyl, and 3-biphenyl are also independently selected. Compound described in 1.

[S jRn R ¹⁵ and R ¹⁸ -R ²² are hydrogen, methyl, t-butyl, phenol, 1-naphthyl, 2 naphthyl, 4-biphenyl, and 3-biphenyl, independently selected groups The compound according to [20] above, wherein

[22] The compound according to [20] or [21] above, wherein the two 2,2,1-biviridine 5-yl groups are the same.

[SS R ¹⁵ and ~ are hydrogen, the [20] or [21] compound of according to claim.

And R ⁴ carbyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1-naphthyl, 2-naphthyl, biphenylyl, and terfenylyl independently selected A group;

R ² and R ³ are hydrogen;

[25]! ^ And R ⁴ are groups in which methyl, t-butyl, phenol, 1-naphthyl, 2-naphthyl, 4-biphenyl, and 3-biphenyl are also independently selected. Compound described in 1. [26] R ^{11 to} R ¹⁵ and R ^{18 to} R ²² are independently selected from hydrogen, methyl, t-butyl, phenol, 1-naphthyl, 2-naphthyl, 4-biphenyl, and 3-biphenyl. The compound according to item [25], which is a group.

[27] The compound according to [25] or [26] above, wherein the two 2,2,1 bibilyidine 5-yl groups are the same. [δ]! ^ ¹¹ ! ^ ¹⁵ and the compound according to [25] or [26] above, wherein R ^{18 to} R ²² are hydrogen.

[29] An organic electroluminescent device, wherein the electron transport layer and Z or the electron injection layer contain the compound according to any one of [1] to [28].

[30] The item [29], wherein the light-emitting layer contains at least one selected from an anthracene derivative, a pyrene derivative, a force rubazole derivative, and an aluminum complex force as a light-emitting material. Organic electroluminescent device.

[31] The organic electroluminescent element as described in the above item [29], wherein the light emitting layer contains an anthracene derivative as a light emitting material.

[32] The organic electroluminescent element as described in the above item [29], wherein the light emitting layer contains a pyrene derivative as a light emitting material.

[33] The organic electroluminescent element as described in the above item [29], wherein the light emitting layer contains a force rubazole derivative as a light emitting material.

[34] The organic electroluminescent element as described in the above item [29], wherein the light emitting layer contains an aluminum complex as a light emitting material. [35] The light-emitting layer is at least one selected from a perylene derivative, a borane derivative, an amine-containing styryl derivative, an aromatic amine derivative, a coumarin derivative, a pyran derivative, an iridium complex, and a platinum complex as a luminescent dopant. The organic electroluminescent element as described in the item [29] above, comprising:

[36] The organic electroluminescent element as described in the above item [29], wherein the light emitting layer contains a perylene derivative as a light emitting dopant.

[37] The organic electroluminescent element as described in the above item [29], wherein the light emitting layer contains a borane derivative as a light emitting dopant.

[38] The organic electroluminescent element as described in the above item [29], wherein the light emitting layer contains an amine-containing styryl derivative as a light emitting dopant.

[39] The organic electroluminescent element as described in the above item [29], wherein the light emitting layer contains an aromatic amine derivative as a light emitting dopant.

[40] The organic electroluminescent element as described in the above item [29], wherein the light emitting layer contains a coumarin derivative as a light emitting dopant.

[41] The organic electroluminescent element as described in the above item [29], wherein the light emitting layer contains a pyran derivative as a light emitting dopant.

[42] The organic electroluminescent element as described in the above item [29], wherein the light emitting layer contains an iridium complex as a light emitting dopant.

[43] The organic electroluminescent element as described in the above item [29], wherein the light emitting layer contains a platinum complex as a luminescent dopant. The invention's effect

[0013] The compound of the present invention applies voltage in a thin film state! It is stable and has a high charge transport capability. The compounds of the present invention are suitable as charge transport materials and charge injection materials in organic EL devices! / By using the compound of the present invention for the electron transport layer and the Z or electron injection layer of the organic EL device, an organic EL device having a low driving voltage and a long lifetime can be obtained. Since the compound of the present invention can reduce the driving voltage and extend the life of a blue light emitting element, a high-performance display device such as a full color display can be created by using the organic EL element of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

[0014] Hereinafter, the present invention will be described in more detail.

The first of the present invention is a compound represented by the following formula (1), which has a structure in which two 2,2, -biviridine-5-yl groups are linked to the 9,10-positions of anthracene.

Hereinafter, in this specification, “the compound represented by the formula (1)” is expressed as “the compound (1)”. Similarly, “compound represented by formula (1-1)”, “compound represented by formula (1-2)”, etc. are referred to as “compound (1-1)”, “compound (1-2)”, etc. May be written.

[0015] In the present specification, a group formed by R ^{9 to} R ¹⁵ and 2, 2, -biviridine-5-yl nucleus, and R ^{la to} R ²² and 2, 2, monobiviridine-5-yl nucleus The group formed in is called a 2, 2, 1 bibiridin-5-yl group. In the formula (1), the two 2, 2, -biviridine-5-yl groups may be the same or different, but are preferably the same.

In compound (1), I ^ to R ⁴ may all be hydrogen, but are independently alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, and optionally substituted 6 to 6 carbon atoms. 18 aromatic ring systems, Alternatively, it may be substituted or a monovalent group such as a heteroaromatic ring having 2 to 18 carbon atoms. When these monovalent groups are introduced into 1 ^ to R ⁴ , the crystallinity of the compound of formula (1) is lowered, which has the effect of forming a stable thin film. Furthermore, by introducing one or more of these monovalent groups I ^ to R ^4, by an asymmetrical structure, the crystallinity of the compound is further lowered, the stability of the thin film state is above improvement. If these compounds are used in the electron transport layer and the Z or electron injection layer of an organic EL device, the drive of the device is stabilized, and it is thought that it contributes to the long life of the device. However greens grounds, in order to lower the driving voltage of the organic EL element is adjacent to it it desirable instrument electron transfer is efficiently performed between molecules I ^ to R ⁴ is a monovalent group above Of these, 1 to 2 are preferred. When there are a plurality of monovalent groups, they may be the same or different. In addition, the position at which the monovalent group is introduced is not selected.

[0017] Next, these monovalent groups will be specifically described.

The alkyl having 1 to 6 carbon atoms may be linear or branched. Examples of the alkyl having 1 to 6 carbon atoms are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, pentyl, hexyl and the like, and preferred examples are methyl and t-butyl.

Examples of the cycloalkyl having 3 to 6 carbon atoms are cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like, and a preferred example is cyclohexyl.

An aromatic ring system having 6 to 18 carbon atoms is a monovalent group derived from an aromatic monocyclic hydrocarbon having 6 to 18 carbon atoms or a condensed polycyclic aromatic hydrocarbon having 6 to 18 carbon atoms, or a plurality thereof. It is a monovalent group composed of a combination of aromatic ring groups. Examples of aromatic ring systems with 6 to 18 carbon atoms are: phenol, 1-naphthyl, 2 naphthyl, 2 biphenyl, 3 biphenyl, 4 bifurinole, m-terfeninole 1, 1inole, m —Tuffeninore 4, 1-inole, m—Taffeninore 5, 5-inole, o Turfinore 3, 3-inole, o Turfinore 4, 4-inole, p Preferred examples are phenyl, 1-naphthyl, 2-naphthyl, 4-biphenylyl, and 3-biphenylyl.

[0018] The heteroaromatic ring having 2 to 18 carbon atoms contains 1 to 5 heteroatoms selected from an oxygen atom, a sulfur atom and a nitrogen atom in addition to the 2 to 18 carbon atoms constituting the ring. It is a terror fragrance ring. Examples of heteroaromatic rings having 2 to 18 carbon atoms are furyl, chael, pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, oxy Sadazolyl, furazanyl, thiadiazolyl, triazolyl, tetrazolyl, pyridyl, pyrimidyl, pyridazyl, pyrazyl, triazyl, benzofural, isobenzofural, benzo [b] chell, indolyl, isoindolyl 1H-indazolyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, 1H-benzotriazolyl, quinolyl, isoquinolyl, cinnolyl, quinazolyl, quinoxalinyl, phthaladil, naphthyridinyl, purinyl, pteridinyl, carbazolyl, etharidinyl Examples include phenothiazinyl, phenadyl, phenoxathiyl, thiantrail, indolizyl and the like. Preferred examples are chenyl, oxadiazolyl, pyridyl, benzo [b] chenyl, quinolyl, strength rubazolyl and the like.

[0019] Examples of the substituents on which these aromatic ring systems or heteroaromatic rings may be substituted are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sbutyl, t-butyl, pentenole, cyclo Alkyl such as pentinole, hexinole, cyclohexenole, heptinole, cycloheptinole, octyl, cyclooctyl, trifluoromethyl, etc .; aryls such as phenyl, naphthyl, anthracyl, phenanthryl; methylphenol, ethylphenol , S butyl phenyl, t butyl phenyl, 1 methyl naphthyl, 2 methyl naphthyl, 4 methyl naphthyl, 1,6 dimethyl naphthyl, 1 ethyl naphthyl, 2 ethyl naphthyl, 4 ethyl naphthyl, 1, 6 jetyl naphthyl, 4 tert-butyl naphthyl ; Pyridyl, quinazolyl, quinolyl Pyrimidine - - Le, furyl, Choi Le, pyrrolyl, imidazolyl, tetrazolyl, hetero rings such as Fuenanto port Riniru; and Shiano the like. The number of substituents is, for example, the maximum number that can be substituted, and is preferably 1 to 3, more preferably 1 to 2.

[0020] R ⁵ ~R ⁸ are independently hydrogen, cycloalkyl Le 3-6 alkyl carbon atoms or 1 to 6 carbon atoms. R ^{5 to} R ⁸ may be hydrogen or short alkyl (methyl, ethyl, t-butyl, etc.) to avoid steric hindrance with the 9, 10-position 2, 2, -biviridine-5-yl group. More preferred is hydrogen.

[0021] R ⁹ , R ¹⁰ , R ¹⁶ , and R ¹⁷ in the 2, 2, -biviridine-5-yl group are independently hydrogen, alkyl having 1 to 6 carbons, or cyclohexane having 3 to 6 carbons. Alkyl. For the same reason as above, hydrogen, methyl or t-butyl is preferred, and hydrogen is more preferred. Yes.

[0022] R ^{U to} R ¹⁵ and R ^{18 to} R ²² are independently hydrogen, alkyl having 1 to 6 carbons, cycloalkyl having 3 to 6 carbons, an aromatic ring system having 6 to 18 carbons, or substituted. It may be a heteroaromatic ring having 2 to 18 carbon atoms. These alkyls having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, aromatic ring systems having 6 to 18 carbon atoms, and optionally substituted heteroaromatic rings having 2 to 18 carbon atoms are represented by the above I ^ to R Examples similar to those described in the explanation of ⁴ are exemplified, and the same groups are preferred.

[0023] <Specific examples of compounds>

Specific examples of the compounds of the present invention are shown by the formulas listed below, but the present invention is not limited by the disclosure of these specific structures.

Specific examples of the compound represented by the formula (1) are the following compounds (11) to (1100). Among these, preferred compounds are (1 1) to (1 5), (1 7) to (1 11), (1-13), (1 21), (1 23), (1 26), (1 27), (1 39) to (1 41), (1 43), and (1 96) to (1 98). More preferred! /, The compounds are compounds (11) to (14). The symbols Me and t Bu in the formula represent methyl and t-butyl, respectively.



[0028]

[0029]



[0031]

20

(1-99)

[0034] <Synthesis of compounds>

The compound of the present invention can be synthesized by a known method such as Suzuki coupling reaction or Negishi coupling reaction. It can also be synthesized by combining both reactions. First, the synthesis method of compound (1) in which the same 2,2, -biviridine-5-yl group is substituted at the 9,10-position of anthracene is exemplified below. Scheme 1: Suzuki coupling

Pd-catalyst I base In the above formula, X is chlorine, bromine, iodine, or triflate. R is a short-chain alkyl, and usually methinole, ethinole, isopropyl and the like are preferably used. ! The definition of ^ to ¹⁵ is the same as above. G represents the following anthracene 9, 10 gil.

Scheme 2: Negishi coupling

Pd-catalyst

X-G-X ► (1)

Pd-catalyst In the above formula, X! ^ ~ ⁵ and -G are as defined above.

[0036] Scheme 1 shows an example of the Suzuki coupling reaction. The reaction of 1-1) is a method in which 2,2'-biviridine having a 2-fold mole of reactive groups is reacted with anthracene in which the 9 and 10-positions are boronic acid in the presence of a palladium catalyst and a base. It is. The reaction of 1-2) is a method in which anthracene having reactive groups at the 9 and 10-positions is reacted with 2-fold moles of 2,2'-biviridine boronic acid in the presence of a palladium catalyst and a base. is there. In these reactions, boronic acid esters are also preferably used instead of boronic acid.

[0037] An example of the Negishi coupling reaction is shown in Scheme 2. The reaction of 2-1) is a method of reacting 2,2'-biviridine having a 2-fold mole of reactive groups in the presence of a palladium catalyst with anthracene in which the 9, 10-position is a zinc complex. . The reaction of 2-2) is a method in which an anthracene having a reactive group at two positions of the 9, 10-positions is reacted with a double mole of a 2,2'-biviridine zinc complex in the presence of a palladium catalyst. In both schemes 1 and 2, the process of reacting one kind of 2,2'-biviridine derivative with a 2-fold molar reaction with the anthracene derivative is explained. In the resulting compound, the formula (1) defined above is used. 2, 2 'chatter Gin - 5-I le substituent group has is R ¹⁶ is R ^9, R ¹⁷ is R ^10, R ¹⁸ is ^1, R ¹⁹ is R ^12, R ² ° is R ^13, R ²¹ Needless to say, R ¹⁴ and R ²² can be read as R ¹⁵ respectively. [0038] Next, a method for synthesizing compound (1) in which a different 2,2,1-biviridine-5-yl group is substituted at the 9,10-positions of anthracene is exemplified below.

Scheme 3

(0)

Pd-catalyst I base

Pd-catalyst In the above formula, X! The definitions of ^ to ⁵ and —G— are the same as described above.

[0039] Synthesis example of reaction intermediate (0) is shown in Scheme 3 above. In the reaction of 3-1), anthracene with boronic acid at one of the 9, 10-positions is reacted with 2,2'-biviridine having an equimolar reactive group in the presence of a palladium catalyst and a base. Is the method. In the reaction of 3-2), anthracene having a reactive group at two positions in the 9, 10-position, in the presence of a palladium catalyst and a base, In this method, equimolar 2,2′-biviridine boronic acid is reacted. In these reactions, boronic acid esters are also preferably used instead of boronic acid. The reaction of 3-3) is a method in which an anthracene having a zinc complex at one of the 9, 10-positions is reacted with 2,2'biviridine having an equimolar reactive group in the presence of a palladium catalyst. The reaction of 3-4) is a method in which equimolar 2,2'-biviridine zinc complex is reacted with anthracene having a reactive group at two positions of 9, 10 in the presence of a palladium catalyst.

Scheme 4

Pd -catalyst In the above formula, X! ^ ~ ² and —G are as defined above.

Scheme 4 above shows a method for synthesizing the compound represented by the formula (1) from the reaction intermediate (0). The reaction of 4-1) is a method in which the reactive group of (0) is converted to boronic acid, and 2,2′-biviridine having an equimolar reactive group is reacted in the presence of a palladium catalyst and a base. 4- 2) The reaction of (0) is carried out with equimolar 2,2 ′ biviridine borate in the presence of palladium catalyst and base. This is a method of reacting with ronic acid. In these reactions, a boronic acid ester is also preferably used in place of the boronic acid. The reaction of 4-3) is a method in which the reactive group of (0) is converted to a zinc complex and 2,2'biviridine having an equimolar amount of the reactive group is reacted in the presence of a palladium catalyst. The reaction of 4-4) is a method in which (0) is reacted with an equimolar 2,2'-biviridine zinc complex in the presence of a palladium catalyst.

[0041] Specific examples of the palladium catalyst used in the Suzuki coupling reaction include Pd (PPh), PdCl

3 4 2

(PPh), Pd (OAc), Tris (dibenzylideneacetone) dipalladium (0), Tris (Dibe

3 2 2

Ndylideneacetone) dipalladium black-form complex (0) and the like. In order to accelerate the reaction, a phosphinic compound may be added to these palladium compounds. Specific examples of the phosphine compound include tri (t-butyl) phosphine, tricyclohexylphosphine, 1- (N, N-dimethylaminomethyl) 1-2- (di-t-butylphosphino) phenocene, 1- (N, N— Dibutylaminomethyl) -2- (di-t-butylphosphino) phenocene, 1- (methoxymethyl) -2- (di-t-butylphosphino) phenocene, 1,1, -bis (di-t-butylphosphino) ferrocene, 2,2,1bis (di-t-butylphosphino) -1,1,1'-binaphthyl, 2-methoxy-1,2- (di-t-butylphosphino) -1,1,1'-binaphthyl, 2-dicyclohexylphosphino-2 ', 6'-dimethoxy biphenyl and the like. Specific examples of the base used in this reaction are sodium carbonate, potassium carbonate, cesium carbonate, sodium hydrogen carbonate, sodium hydroxide, potassium hydroxide, barium hydroxide, sodium ethoxide, sodium t-butoxide, acetic acid. Sodium, tripotassium phosphate, potassium fluoride and the like. Furthermore, specific examples of the solvent used in this reaction include benzene, toluene, xylene, N, N dimethylformamide, tetrahydrofuran, jetyl ether, t-butyl methyl ether, 1,4 dioxane, methanol, ethanol, isopropyl alcohol, and the like. It is. These solvents can be appropriately selected and may be used alone or as a mixed solvent.

[0042] Specific examples of the palladium catalyst used in the Negishi coupling reaction include Pd (PPh), PdCl

3 4 2

(PPh), Pd (OAc), Tris (dibenzylideneacetone) dipalladium (0), Tris (Dibe

3 2 2

Benzylideneacetone) dipalladium (0), bis (tri-tert-butylphosphino) palladium (0), (1,1,1bis (diphenylphosphino) phenolic) dichloropalladium (II) and the like. Furthermore, specific examples of the solvent used in this reaction are benzene, toluene, xylene, N, N— Dimethylformamide, tetrahydrofuran, jetyl ether, t-butyl methyl ether, 1,4 dioxane and the like. These solvents can be appropriately selected, and may be used alone or as a mixed solvent.

[0043] When the compound of the present invention is used for an electron injection layer, an electron transport layer or a hole blocking layer in an organic EL device, it is stable when an electric field is applied, and light emission can be obtained at a low voltage. It becomes possible. These indicate that the compound of the present invention is excellent as an electron injection material, an electron transport material, or a hole blocking layer of an electroluminescent element. Here, the electron injection layer is a layer that receives electrons into the cathode force organic layer, the electron transport layer is a layer for transporting injected electrons to the light emitting layer, and the hole blocking layer is a light emitting layer. This is a layer for confining holes. The electron transport layer can also serve as the electron injection layer and the Z or hole blocking layer. The materials used for each layer are called an electron injection material, an electron transport material, and a hole blocking material.

[0044] <Description of organic EL device>

A second aspect of the present invention is an organic EL device containing a compound represented by the formula (1) of the present invention in an electron injection layer, an electron transport layer, or a hole blocking layer. The organic EL element according to a preferred embodiment of the present invention has high durability during driving when the driving voltage is low.

[0045] The structure of the organic EL device of the present invention has various aspects. Basically, it has a multilayer structure in which at least a hole transport layer, a light emitting layer, and an electron transport layer are sandwiched between an anode and a cathode. Examples of the specific configuration of the device are: (1) anode Z hole transport layer Z light emitting layer Z electron transport layer Z cathode, (2) anode Z hole injection layer Z hole transport layer Z light emitting layer Z electron transport layer Z cathode, (3) anode Z hole injection layer Z hole transport layer Z light emitting layer Z electron transport layer Z electron injection layer Z cathode, and the like.

[0046] Since the compound of the present invention has high electron injecting property and electron transporting property, it can be used as an electron injecting layer, an electron transporting layer or a hole blocking layer alone or in combination with other materials. The organic EL device of the present invention emits blue, green, red or white light by combining the electron transport material of the present invention with a hole injection layer, a hole transport layer, a light emitting layer, etc. using other materials. Get away with it.

[0047] The light-emitting material or light-emitting dopant that can be used in the organic EL device of the present invention is described in Polymer Science Society, Polymer Functional Material Series "Optical Functional Material", Joint Publication (1991), P236. Luminescent materials such as daylight fluorescent materials, fluorescent brighteners, laser dyes, organic scintillators, various fluorescent analysis reagents, etc., supervised by Koji Koji, "Organic EL materials and displays", published by CMC Company (2001) P 155 to 156 !, dopant materials such as those described above, and triplet material luminescent materials such as those described in P 170 to 172.

[0048] The compounds that can be used as the light-emitting material or the light-emitting dopant include polycyclic aromatic compounds, heteroaromatic compounds, organometallic complexes, dyes, polymer-based light-emitting materials, styryl derivatives, aromatic amine derivatives, coumarin derivatives, and boranes. Derivatives, oxazine derivatives, compounds having a spiro ring, oxaziazole derivatives, fluorene derivatives, and the like. Examples of the polycyclic aromatic compound are anthracene derivatives, phenanthrene derivatives, naphthacene derivatives, pyrene derivatives, taricene derivatives, perylene derivatives, coronene derivatives, rubrene derivatives, and the like. Examples of heteroaromatic compounds include oxadiazole derivatives having a dialkylamino group or a diarylamino group, pyrazoguchi quinoline derivatives, pyridine derivatives, pyran derivatives, phenanthorin derivatives, silole derivatives, thiophene derivatives having a triphenylamino group, Quinacridone derivatives and the like. Examples of organometallic complexes are zinc, aluminum, beryllium, europium, terbium, dysprosium, iridium, platinum, osmium, gold, etc., quinolinol derivatives, benzoxazole derivatives, benzothiazole derivatives, oxadiazole derivatives, thiadiazole derivatives , Benzimidazole derivatives, pyrrole derivatives, pyridine derivatives, phenantorin derivatives, and the like. Examples of dyes are xanthene derivatives, polymethine derivatives, porphyrin derivatives, coumarin derivatives, dicyanmethylenepyran derivatives, dicyanomethylenethiopyran derivatives, oxobenzanthracene derivatives, carbostyril derivatives, perylene derivatives, benzoxazole derivatives, Examples thereof include pigments such as benzothiazole derivatives and benzimidazole derivatives. Examples of the polymer light-emitting material are polyparaphenylene biylene derivatives, polythiophene derivatives, polybulur rubazole derivatives, polysilane derivatives, polyfluorene derivatives, polyparaphenylene derivatives, and the like. Examples of styryl derivatives are ammine-containing styryl derivatives, styryl arylene derivatives, and the like.

[0049] Other electron transport materials used in the organic EL device of the present invention include a compound that can be used as an electron transporting compound in a photoconductive material, an electron transport layer of the organic EL device, and electron injection. Any compound that can be used in the layer can be selected and used.

[0050] Specific examples of such electron transport materials include quinolinol metal complexes, 2,2'-bibilidyl derivatives, phenanthorin derivatives, diphenylquinone derivatives, perylene derivatives, oxadiazole derivatives, thiophene derivatives, triazoles. Derivatives, thiadiazole derivatives, metal complexes of oxine derivatives, quinoxaline derivatives, polymers of quinoxaline derivatives, benzazole compounds, gallium complexes, pyrazole derivatives, perfluorinated phenylene derivatives, triazine derivatives, pyrazine derivatives, benzoquinolines Derivatives, imidazopyridine derivatives, borane derivatives and the like.

[0051] Regarding the hole injection material and the hole transport material used in the organic EL device of the present invention, in the photoconductive material, a compound conventionally used as a charge transport material for holes or an organic EL device is used. Any known material used for the hole injection layer and the hole transport layer can be selected and used. Specific examples thereof are force rubazol derivatives, triarylamine derivatives, phthalocyanine derivatives and the like.

[0052] Each layer constituting the organic EL device of the present invention can be formed by forming a material to constitute each layer into a thin film by a method such as a vapor deposition method, a spin coat method, or a cast method. The film thickness of each layer formed in this way is not particularly limited, and can be set as appropriate according to the nature of the material. Usually 2ηπ! It is in the range of ~ 5000nm. As a method of thinning the light emitting material, it is preferable to employ a vapor deposition method from the standpoint that a homogeneous film can be obtained and pinholes are not easily formed. When thinning using the vapor deposition method, the vapor deposition conditions differ depending on the type of the light emitting material of the present invention. The deposition conditions are generally boat heating temperature of 50 to 400 ° C, vacuum degree of 10 ^_6 to 10 ^_3 Pa, deposition rate 0. 01～50NmZ sec, a substrate temperature 150 to + 300 ° C, film thickness 5nm~5 μ m It is preferable to set appropriately within the range.

[0053] The organic EL device of the present invention is preferably supported by a substrate in any of the structures described above. The substrate only needs to have mechanical strength, thermal stability and transparency, and glass, a transparent plastic film and the like can be used. As the anode material, metals, alloys, electrically conductive compounds and mixtures thereof having a work function larger than 4 eV can be used. Specific examples thereof include metals such as Au, Cul, indium tinoxide (hereinafter abbreviated as ITO), SnO, ZnO, and the like. [0054] As the cathode material, a metal, an alloy, an electrically conductive compound having a work function smaller than 4 eV, or a mixture thereof can be used. Specific examples thereof are aluminum, calcium, magnesium, lithium, magnesium alloy, aluminum alloy and the like. Specific examples of the alloy are aluminum Z lithium fluoride, aluminum Z lithium, magnesium Z silver, magnesium Z indium and the like. It is desirable that at least one of the electrodes has a light transmittance of 10% or more in order to efficiently extract the light emitted from the organic EL device. The sheet resistance as an electrode is preferably several hundred Ω / □ (Ω / sq) or less. Although the film thickness depends on the properties of the electrode material, it is usually set in the range of 10 nm to 1 μm, preferably 10 to 400 nm. Such an electrode can be produced by forming a thin film by a method such as vapor deposition or sputtering using the electrode material described above.

[0055] Next, as an example of a method for producing an organic EL device using the light emitting material of the present invention, the above-described anode Z hole injection layer Z hole transport layer Z light emitting layer Z electron transport material Z cathode of the present invention A method for producing an organic EL device consisting of A thin film of an anode material is formed on a suitable substrate by vapor deposition to produce an anode, and then a thin film of a hole injection layer and a hole transport layer is formed on the anode. A light emitting layer thin film is formed thereon. On this light emitting layer, the electron transport material of this invention is vacuum-deposited, a thin film is formed, and it is set as an electron carrying layer. Furthermore, the target organic EL device can be obtained by forming a thin film of material for the cathode by a vapor deposition method to form a cathode. In the preparation of the above-mentioned organic EL element, it is possible to reverse the production order and produce the cathode, the electron transport layer, the light emitting layer, the hole transport layer, the hole injection layer, and the anode in this order. .

[0056] When a DC voltage is applied to the organic EL device thus obtained, it is sufficient to apply a voltage of about 2 to 40 V when the anode is + and the negative electrode is one polarity. Luminescence can be observed from the semi-transparent electrode side (anode or cathode and both). The organic EL element also emits light when an alternating voltage is applied. The alternating current waveform to be applied may be arbitrary.

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

[Synthesis Example 1: Synthesis of Compound (1 1)]

[0057] <9, 10 Bis (4, 4, 5, 5—tetramethyl-1, 3, 2 dioxaborola) anthrac Synthesis>

9, 10 Dibromoanthracene 2.99 g, bis (pinacolato) diboron 5 g, palladium (0) bis (dibenzylideneacetone) 614 mg, tricyclohexylphosphine 724 mg, acetic acid potassium 2.6 g, and dioxane 80 ml are placed in a flask. The mixture was stirred at reflux temperature for 20 hours under an atmosphere. After completion of the heating, the reaction solution was cooled to room temperature, pure water was added, and the organic layer was extracted. The organic layer is concentrated by an evaporator, the concentrate is purified by silica gel column chromatography using toluene as a moving bed, and the powder obtained by concentrating again is washed with methanol, and 9, 10 bis (4, 4, 4, 5,5-tetramethyl-1,3,2 dioxaboral)) anthracene 2.3 g was obtained.

[0058] <5 Synthesis of bromo-2,2, bibilysine>

Nitrogen gas stream, 120 ml of toluene solution containing 14 ml of 2 bromopyridine was cooled to 78 ° C., and 100 ml of hexane solution of 1.59 molZl of n-butyllithium was prepared. After stirring at −78 ° C. for 35 minutes, 40 g of sodium chloride zinc tetramethylethylenediamine was added and stirred at room temperature for 30 minutes. 2,5 dibromopyridine 40 g, Pd (PPh) 8.3 g

3 4

Stir for 2 hours. After completion of heating, the reaction solution was cooled to room temperature and filtered through celite. The filtrate was concentrated, and the concentrate was purified by silica gel chromatography using a mixed solvent of formaldehyde / ethyl acetate in a moving bed and concentrated again to recrystallize the powder with ethyl acetate. Bromo-2,2,1biviridine 4.lg was obtained.

[0059] <Synthesis of 9, 10bis (2,2,1biviridine-5-yl) anthracene>

9, 10 Bis (4, 4, 5, 5—tetramethyl-1, 3, 2 dioxaborolanyl) anthracene 2g, 5 bromo 2, 2, monobiviridine 2.4g, Pd (PPh) 322mg, triphosphate Potassium 3.

3 4

95 g, 50 ml of dioxane and 10 ml of pure water were placed in a flask and stirred overnight at the reflux temperature under an argon atmosphere. After completion of the heating, the reaction solution was cooled to room temperature, pure water was added, and the organic layer was extracted. The organic layer is concentrated by an evaporator, and the concentrate is purified by silica gel silica gel column chromatography using a mixed solvent of toluene and ethyl acetate in the moving bed.

The powder obtained by concentration again was recrystallized with toluene to obtain 1.lg of 9,10bis (2,2'-biviridine-5 yl) anthracene.

1H-NMR (CDC1): δ = 7.3—7.4 (m, 6H), 7.7—7.8 (m, 4H), 7.9 (t, 2H), 7.95—8.05 (m , 2H), 8.6 (d, 2H), 8.7 (d, 2H), 8.8-8.9 (m, 4H).

[Synthesis Example 2: Synthesis of Compound (1 2)]

[0060] Synthesis of 2 Hue-Noranthracene>

2 Black mouth anthracene 5. OOg, phenol boronic acid 4.3 g, tris (dibenzylideneacetone) dipalladium (0) 538 mg, tricyclohexylphosphine 494 mg, tripotassium phosphate 9.98 g, and toluene 75 ml The mixture was stirred at reflux temperature for 2 hours under an argon atmosphere. After completion of the heating, 1.5 liters of toluene was added to the reaction solution, cooled to room temperature and filtered, and the filtrate was purified by silica gel column chromatography (mobile phase: toluene) using toluene as a moving bed. The solvent was distilled off under reduced pressure, and the concentrate was recrystallized also with toluene to give 2-phenolinanthracene 5. Og.

In a flask under a nitrogen atmosphere, 3.32 g of 2-phenylanthracene was dissolved in 400 ml of dichloromethane. A solution prepared by dissolving 5.00 g of bromine in 30 ml of tetrasalt-carbon was added dropwise over 15 minutes. After completion of the dropwise addition, the mixture was stirred for 2 hours at room temperature, and the reaction was stopped with an aqueous sodium thiosulfate solution. The organic layer was extracted with a separatory funnel and concentrated with an evaporator. The concentrate was recrystallized with 50 ml of toluene to obtain 4.4 g of 9, 10 jib mouth moe 2 phenolanthracene.

[0061] <Synthesis of 9, 10 Bis (4, 4, 5, 5—Tetramethyl-1,3,2 Dioxaboral) 2 Feranthracene>

9, 10 Jib mouth mo 2 Phenylanthracene 10. Og, Bis (pinacolato) diboron 14.8g, Bis (dibenzylideneacetone) palladium (0) 838mg, Tricyclohexylphosphine 1.02g, Potassium acetate 7.15g and 50 ml of 1,4 dioxane was placed in a flask and stirred at reflux temperature for 8 hours under argon atmosphere. After the heating was completed, toluene was added to the reaction solution, the solution was cooled to room temperature and filtered, and the filtrate was concentrated by an evaporator. The concentrate was purified by silica gel column chromatography using toluene as the moving bed, and then recrystallized with a mixed solution of tetrahydrofuran and Z-heptane. 9, 10 Bis (4, 4, 5, 5-tetramethyl-1, 3, 2 Dioxaborolaninole) 2 Phenolinanthracene 8.3 g was obtained.

[0062] Synthesis of 9, 10 bis (2, 2, 1-biviridine-5-yl) 2 -phenylanthracene> 9, 10 Bis (4, 4, 5, 5—Tetramethyl 1, 3, 2 Dioxabolananyl) 2 Phenylanthracene 0.80 g, 5 Bromo 2, 2, 1 biviridine 0.83 g, Tris (dibenzylideneacetone) ) 88 mg of dipalladium (0), 8 lmg of tricyclohexylphosphine, 1.36 g of tripotassium phosphate and 35 ml of toluene were placed in a flask and stirred at reflux temperature for 27 and a half hours under an argon atmosphere. After completion of the heating, the reaction solution was cooled to room temperature and pure water was added to extract the organic layer. The organic layer was concentrated by an evaporator, and the concentrate was purified by activated alumina column chromatography using toluene as the moving bed. Recrystallization was performed in a mixed solvent of black mouth form / ethyl acetate to obtain 198 mg of 9,10bis (2,2, -biviridine-5-yl) -2 phenolanthracene.

1H—NMR (CDC1): δ = 7.3 (t, 1H), 7.4 (m, 6H), 7.6 (d, 2H), 7.7 (m, 3H), 7.8 (

Three

d, 1H), 7.9 (m, 3H), 8.0 (m, 2H), 8.6 (d, 2H), 8.7 (d, 2H), 8.8 (m, 2H), 8.9 (m, 2H)

[0063] By appropriately selecting the starting compound, other compounds of the present invention can be synthesized by a method according to the above synthesis example.

Example 1

[0064] A glass substrate (manufactured by Tokyo Sanyo Vacuum Co., Ltd.) of 25 mm X 75 mm X l. 1 mm on which ITO was deposited to a thickness of 150 nm was used as a transparent support substrate. This transparent support substrate is fixed to a substrate holder of a commercially available vapor deposition system (manufactured by Vacuum Co., Ltd.), and a molybdenum vapor deposition boat containing copper phthalocyanine, N, N, —Diferro-N, N, —Dinaphthyl — Molybdenum deposition boat with 4, 4'-diaminobiphenyl (hereinafter abbreviated as NPD), the following compound (2): 9-Fuel 10- [6- (1, 1 ,; 3, 1,,) terferyl 5, 1 yl] naphthalene 1 -2-yl] molybdenum vapor deposition boat with anthracene, styrylamine derivatives (3): N, N, Ν ', N'— Molybdenum vapor deposition boat containing tetra (4-biphenyl) 4, 4, 1-diaminostilbene, molybdenum vapor deposition boat containing compound (11), molybdenum vapor deposition containing lithium fluoride Equipped with a boat and a tungsten evaporation boat containing aluminum

^{Depressurize the} vacuum chamber to 1 X 10 ^_d Pa, heat the vapor deposition boat containing copper phthalocyanine, and form a hole injection layer by vapor deposition to a film thickness of 20 nm, then for vapor deposition containing NPD The boat was heated and NPD was deposited to a film thickness of 30 nm to form a hole transport layer. Next, the vapor deposition boat containing the compound (2) and the vapor deposition boat containing the compound (3) were heated at the same time to form a light emitting layer by vapor deposition to a film thickness of 30 nm. The deposition rate was adjusted so that the weight ratio of compound (2) to compound (3) was approximately 95 to 5. Next, the evaporation boat containing the compound (11) was heated and evaporated to a thickness of 20 nm to form an electron transport layer. The above deposition rate was 0.001 to 3. OnmZ seconds. After that, the vapor deposition boat containing lithium fluoride is heated to deposit at a deposition rate of 0.003-0. OlnmZ seconds so that the film thickness becomes 0.5 nm, and then the vapor deposition boat containing aluminum is heated. Then, an organic EL device was obtained by vapor deposition at a vapor deposition rate of 0.1 to 1. OnmZ seconds so that the film thickness was lOOnm. When a DC voltage was applied using the ITO electrode as the anode and the lithium fluoride Z-aluminum electrode as the cathode, blue light emission with a wavelength of about 455 nm was obtained. The voltage applied to obtain luminance lOOOcdZm ² was 5.09V. When a constant current driving test was performed while maintaining the current density at this time, the luminance after 80 hours was 813 cdZm ² . Based on initial brightness The luminance retention after 80 hours was 81.3%.

Example 2

[0065] An organic EL device was obtained in the same manner as in Example 1 except that the compound (11) was replaced with the compound (12). The voltage applied to obtain a luminance of 1000 cdZm ² with the ITO electrode as the anode and the lithium fluoride / aluminum electrode as the cathode was 5.63V. Was subjected to a constant current driving test holds the current density at this time, the brightness at the time lapse 80 hours was 893cdZm ^2. Based on the initial luminance, the luminance retention rate after 80 hours was 89.3%.

[0066] (Comparative Example 1)

Example except that compound (1-1) was replaced with tris (8 quinolinol) aluminum (Alq)

Three

An organic EL device was obtained in the same manner as in 1. The voltage applied to obtain luminance lOOOcdZm ² with the ITO electrode as the anode and the lithium fluoride Z-aluminum electrode as the cathode was 6.36V. When a constant current driving test was conducted while maintaining the current density at this time, the brightness after 80 hours was 830 cdZm ² . Based on the initial luminance, the luminance retention rate after 80 hours was 83.0%.

[0067] (Comparative Example 2)

The same as Example 1 except that the compound (1 1) was replaced with the following compound (4): 2,5 bis (6,1 (2,2,2 "bibilidyl) 1,1 dimethyl-3,4-dimesitylsilole An organic EL device was obtained using the ITO electrode as the anode and the lithium fluoride / aluminum electrode as the cathode, and the voltage applied to obtain luminance 1 OOOcdZm ² was 4.04 V. The current density at this time was maintained. When the constant current drive test was conducted, the luminance after 80 hours was 572 cdZm ^2. The luminance retention rate after 80 hours based on the initial luminance was 57.2%.

[0068] (Comparative Example 3) Except that the compound (1-1) was replaced with the following compound (5): 9, 10 bis (2,2, -bibilidine-6-yl) anthracene (compound II 4 described in Patent Document 3), Example 1 and Similarly, an organic EL device was obtained. The voltage applied to obtain luminance lOOOcdZm ² with the ITO electrode as the anode and the lithium fluoride Z aluminum electrode as the cathode was 3.71V. When a constant current driving test was conducted while maintaining the current density at this time, the luminance after 80 hours was 496 cdZm ² . Based on the initial luminance, the luminance retention rate after 80 hours was 49.6%

The voltage (V) applied to obtain the initial luminance lOOOcdZm, the initial luminance after the lapse of 80 hours, and the luminance based on it, for the devices prepared in Examples 1 and 2 and Comparative Examples 1 to 3 above. The retention rate (%) is summarized in Table 1.

In addition, based on the voltage (V) applied to obtain the initial luminance of 1000 cdZm ² and the initial luminance after the elapse of 80 hours of the elements prepared in Examples 1 and 2 and Comparative Examples 1 to 3 above. Figure 1 shows the relationship between the luminance retention rate (%).

Compared to the device of Comparative Example 1 using the well-known Alq for the electron transport layer, Comparative Example 2

Three

Although the applied voltage of the element created in (3) and (3) is significantly reduced, the brightness after constant current driving for 80 hours has decreased to about 50 to 57% of the initial value. It lacks stability.

On the other hand, the device prepared in Example 1 using the compound (11) of the present invention for the electron transport layer was 80 hours in spite of the fact that the applied voltage was reduced by 1.27 V compared to the device of Comparative Example 1. rear The luminance retention ratio of this sample is 83.0%, which is comparable to 83.0% of Comparative Example 1, and was prepared in Example 2 using the compound (1-2) of the present invention for the electron transport layer. The applied voltage was 0.73 V lower than the device of Comparative Example 1, and the luminance retention after 80 hours was 89.3%, which was superior to that of Comparative Example 1.

It can be seen that the compound of the present invention is effective in reducing the driving voltage and prolonging the life as compared with the compounds used in Comparative Examples 2 and 3.

Furthermore, the compound of the present invention has a longer lifetime than Comparative Example 3 because the compound having the 2,2′-biviridine-5-yl group of the present invention has a longer lifetime than the compound having the 2,2′-biviridine-6-yl group. It shows that it is better.

In addition, the compound of Example 2 has a longer lifetime than the compound of Example 1. This indicates that the compound having an asymmetric structure by introducing a substituent at the 2-position has improved stability. It is shown that.

Industrial applicability

[0070] According to the present invention, it is possible to provide an organic EL device with better performance in terms of driving voltage and device lifetime. In particular, since the driving voltage and device life of the blue light emitting device can be improved, a high-performance display device equipped with the device can be provided.

Brief Description of Drawings

[0071] FIG. 1 is a plot of drive test start voltage (V) and luminance reduction rate (%) after elapse of 80 hours in the organic EL elements of Examples and Comparative Examples.

Claims

The scope of the claims

[1] A compound having two 2,2 ′ biviridine 5yl groups represented by the following formula (1).

During the ceremony! ^ ¹ to! ^ ⁴ are independently hydrogen, alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, optionally substituted aromatic ring system having 6 to 18 carbon atoms, or optionally substituted A heteroaromatic ring having 2 to 18 carbon atoms;

R ^{5 to} R ⁸ , R ⁹ , R ¹⁰ , R ¹⁶ , and R ¹⁷ are each independently hydrogen, an alkyl having 1 to 6 carbons, or a cycloalkyl having 3 to 6 carbons; and

R ^{U to} R ¹⁵ and R ^{18 to} R ²² are each independently hydrogen, alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, an optionally substituted aromatic ring system having 6 to 18 carbon atoms, Or it is a C2-C18 heteroaromatic ring which may be substituted.

The compound of claim 1, wherein R ⁹ , R ¹⁰ , R ¹⁶ , and R ¹⁷ are hydrogen.

R ^{U to} R ¹⁵ and R ^{18 to} R ²² are hydrogen, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1-naphthyl, 2-naphthyl, biphenyl, and The compound according to claim 2, wherein the terferyl power is an independently selected group.

[4] I ^ to R ⁴ are hydrogen;

R ^{U to} R ¹⁵ and R ^{18 to} R ²² are hydrogen, methyl, ethynole, propyl, isopropyl, butynole, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1 naphthyl, 2-naphthyl, biphenyl, 4. The compound according to claim 3, which is a group independently selected from terferyl strength.

[Five] ! ^ ¹ ~! ^ ⁴ is at least one of methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, hexyl, cyclohexyl, phenol, 1-naphthyl, 2-naphthyl, Biferyl and terferyl forces independently selected groups with the remainder being hydrogen; R ^{U to} R ¹⁵ and R ^{18 to} R ²² are hydrogen, methyl, ethynole, propyl, isopropyl, butynole, isobutyl, 4. The compound according to claim 3, which is a group independently selected from t-butyl, hexyl, cyclohexyl, phenyl, 1-naphthyl, 2-naphthyl, biphenyl-, and terferyl.

[6] R ¹ is methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, hexyl, cyclohexyl, phenyl, 1 naphthyl, 2-naphthyl, biphenylyl, and tert-phenylyl A group to be

R ^{2 to} R ⁴ are hydrogen;

[7] The compound according to any one of claims 1 to 6, wherein two 2, 2, -biviridine-5-yl groups are the same.

[8] An organic electroluminescence device wherein the electron transport layer and the Z or electron injection layer contain the compound according to any one of claims 1 to 7.

[9] The light-emitting layer contains at least one selected from an anthracene derivative, a pyrene derivative, a force rubazole derivative, and an aluminum complex force as a light-emitting material.

The organic electroluminescent element according to claim 8.

[10] The light-emitting layer has at least one selected from a perylene derivative, a borane derivative, an amine-containing styryl derivative, an aromatic amine derivative, a coumarin derivative, a pyran derivative, an iridium complex, and a platinum complex as a luminescent dopant. The organic electroluminescent element according to claim 9, wherein the organic electroluminescent element is contained.