JP4907912B2 - Novel 1,3,5-triphenylbenzene derivative and organic electroluminescence device containing the same - Google Patents

Description

  The present invention relates to a novel 1,3,5-triphenylbenzene derivative useful for forming a wide-gap electron transport layer suitable for a novel phosphorescent material, particularly a blue phosphorescent material, and an organic electroluminescence containing the same. It relates to an element.

  The organic EL element emits light when excitation energy generated by recombination of holes injected from the electrode and the electrode is relaxed to a ground state through a light emission process. However, there are two types of excited states generated by recombination of holes and electrons, a singlet excited state and a triplet excited state, in a ratio of 1: 3. In many cases, a fluorescent material utilizing light emission from a singlet excited state has been used as a light emitting material, and therefore, the internal quantum efficiency is 25% at the maximum. The quantum efficiency was the theoretical limit of 5%.

  In recent years, improvement in luminous efficiency has been reported by using light emission from a triplet excited state, that is, phosphorescence emission, using a complex compound utilizing a heavy atom effect such as iridium or platinum (for example, non-patented) Reference 1). The maximum internal quantum efficiency can theoretically reach 100% by utilizing light emission from the triplet excited state in addition to the singlet excited state, and phosphorescent materials are attracting attention as light emitting materials.

に示すトリス（２−フェニルピリジナト）イリジウム（III）［Ｉｒ（ｐｐｙ）_３］が広く利用されている。 For example, as a green material, the following formula

Tris (2-phenylpyridinato) iridium (III) [Ir (ppy) ₃ ] shown in FIG.

で示すビス［２−（４，６−ジフルオロフェニル）ピリジル−Ｎ，Ｃ２′］イリジウム（III）ピコリレート（ＦＩｒｐｉｃ）が注目を浴びるようになり、それ以降ＦＩｒｐｉｃを用いた有機ＥＬ素子の高効率化検討および新規な青色リン光錯体探索研究が盛んに行われるようになった。 In addition, the following formula, which is a blue light-emitting material according to Non-Patent Document 2 by Adachi et al.

Bis [2- (4,6-difluorophenyl) pyridyl-N, C2 ′] iridium (III) picolylate (FIrpic) has been attracting attention, and since then, the efficiency of organic EL devices using FIrpic has been increased. Studies and new blue phosphorescent complex exploration studies have been actively conducted.

で示すトリス［１−（４−（トリフルオロメチル）フェニル）−１Ｈ−ピラゾラート，Ｎ，Ｃ２′］イリジウム（III）（Ｉｒｔｆｍｐｐｚ３）やＭ．Ｅ．Ｔｈｏｍｐｓｏｎらによる非特許文献４では下記式

で示すビス［２−（４′，６′−ジフルオロフェニル）ピリジナト−Ｎ，Ｃ２′］テトラキス（１−ピラゾリル）ボレート（Ｆｉｒ６）が開発された。 As a result, S. R. Non-patent document 3 by Forrest et al.

Tris [1- (4- (trifluoromethyl) phenyl) -1H-pyrazolate, N, C2 ′] iridium (III) (Irtfmpppz3) and M. E. Non-Patent Document 4 by Thompson et al.

Bis [2- (4 ′, 6′-difluorophenyl) pyridinato-N, C2 ′] tetrakis (1-pyrazolyl) borate (Fir6) has been developed.

In order for these light emitting materials to emit light efficiently, the hole and electron injection balance must be adjusted, and a hole transporting agent or electron transporting agent must be selected so that these carriers can be sufficiently combined in the light emitting layer. .
In particular, since the blue phosphorescent material has a large energy gap, a hole transport agent and an electron transport agent having a wide gap are required. As for these phosphorescent materials, Alq ₃ [tris (8-quinolinolato) aluminum] and BAlq ₂ [bis (2-methyl-8-quinolinolato) aluminum p-phenylphenolate] conventionally used for electron transport materials. However, since it does not have a sufficient energy gap for use in phosphorescent materials, it is necessary to develop a new wide-gap electron transport material.
M.M. A. Baldo, S.M. Lamansky, P.M. E. Burrows, M.M. E. Thompson, S.M. R. Forrest APPLYED PHYSICS LETTER 1999 75 (1) 4-7 Appl. Phys. Lett. 79, 2082 (2001) J. et al. Appl. Phys. 90 5048 (2001) 4 Polyhedron 23 (2004) 419-428

  The first object of the present invention is to provide a novel 1,3,5-triphenylbenzene derivative. The second object of the present invention is to provide a novel organic electroluminescence device using the same.

〔式中、Ａｒ^１は、ピリミジニル基、またはイソキノリル基である〕
本発明の第２は、請求項１記載の１，３，５−トリフェニルベンゼン誘導体を含有することを特徴とする有機エレクトロルミネッセンス素子に関する。
本発明の第３は、請求項１記載の１，３，５−トリフェニルベンゼン誘導体を電子輸送材料として使用したことを特徴とする有機エレクトロルミネッセンス素子に関する。 The first of the present invention relates to a 1,3,5-triphenylbenzene derivative represented by the following general formula (1) .

[ Wherein Ar ¹ represents a pyrimidinyl group or an isoquinolyl group ]
The second invention relates to an organic electroluminescent device characterized by containing the claims 1 Symbol placement No 1,3,5 benzene derivatives.
The third invention relates to an organic electroluminescent device, characterized in that using the claim 1 Symbol placement No 1,3,5 benzene derivative as an electron transport material.

（式中、ＸはＢｒなどのハロゲンであり、Ａｒ^１は前記と同一である。） One method for synthesizing the compound of the present invention is shown by the following reaction formula.

(Wherein, X is halogen such as Br, A ^{r 1} is the same as above.)

Representative compounds in the present invention are shown below.

Examples of other compounds of the present invention are shown below.

(1) According to the present invention, a novel 1,3,5-triphenylbenzene derivative could be provided.
( 2 ) A novel organic electroluminescence device could be provided by using the 1,3,5-triphenylbenzene derivative of the present invention.

  Synthesis Examples and Examples are shown below, but the present invention is not limited thereto.

四つ口フラスコに３−ブロモアセトフェノン（３−ｂｒｏｍｏａｃｅｔｏｐｈｅｎｏｎｅ）（５．９７ｇ，３０ｍｍｏｌ）と無水エタノール（６０ｍＬ）を入れて、窒素気流下０℃まで冷やした。激しく撹拌しながら、ゆっくりテトラクロロシラン（１０．２ｇ、６０ｍｍｏｌ）を滴下し、さらに１時間同温で反応させ、室温に戻した。その後、さらに２４時間反応させた。反応終了後、反応溶液を水に注ぎ、クロロホルムで抽出し、飽和食塩水で洗浄した。無水硫酸マグネシウムで脱水し、溶媒をエバポレーターで除去した。
ＴＨＦ／ｎ−ヘキサンによる再結晶を行い、白い固体の１，３，５−トリス（ｍ−ブロモフェニル）ベンゼン｛１，３，５−ｔｒｉｓ（ｍ−ｂｒｏｍｏｐｈｅｎｙｌ）ｂｅｎｚｅｎｅ（ＴｍＢｒＰｈＢ）｝を得た。収率：８２．１ｍｏｌ％。
構造確認は^１ＨＮＭＲで行った。 Synthesis example 1
(1) Synthesis of 1,3,5-tris (m-bromophenyl) benzene {1,3,5-tris (m-bromophenyl) benzene (TmBrPhB)}

3-Bromoacetophenone (5.97 g, 30 mmol) and absolute ethanol (60 mL) were placed in a four-necked flask and cooled to 0 ° C. under a nitrogen stream. Tetrachlorosilane (10.2 g, 60 mmol) was slowly added dropwise with vigorous stirring, and the mixture was further reacted at the same temperature for 1 hour, and returned to room temperature. Thereafter, the reaction was further continued for 24 hours. After completion of the reaction, the reaction solution was poured into water, extracted with chloroform, and washed with saturated brine. It dehydrated with anhydrous magnesium sulfate and the solvent was removed by an evaporator.
Recrystallization with THF / n-hexane gave 1,3,5-tris (m-bromophenyl) benzene {1,3,5-tris (m-bromophenyl) benzene (TmBrPhB)} as a white solid. Yield: 82.1 mol%.
The structure was confirmed by ¹ HNMR.

四つ口フラスコに１，３，５−トリス（ｍ−ブロモフェニル）ベンゼン｛１，３，５−ｔｒｉｓ（ｍ−ｂｒｏｍｏｐｈｅｎｙｌ）ｂｅｎｚｅｎｅ｝（０．９１ｇ、１．６８ｍｍｏｌ）、４−イソキノリンホウ酸（４−ｉｓｏｑｕｉｎｏｌｉｎｅｂｏｒｏｎｉｃａｃｉｄ）（１．０ｇ、５．７８ｍｍｏｌ）、テトラキス（トリフェニルホスフィン）パラジウム〔Ｐｄ（ＰＰｈ_３）_４〕（３３４ｍｇ、０．２８９ｍｍｏｌ）、トルエン／ＴＨＦ（１／１，１２０ｍＬ）と２ＭＫ_２ＣＯ_３（４０ｍＬ）を入れて、窒素気流下９０℃で２４時間反応させ、１，３，５−トリ〔ｍ−（４−イソキノリル）フェニル〕ベンゼン（ＴｍｉＱＰｈＢ）を得た。反応終了後、反応溶液を水に注ぎ、クロロホルムで抽出し、飽和食塩水で洗浄した。無水硫酸マグネシウムで脱水し、溶媒をエバポレーターで除去した。
精製はカラムクロマトグラフィー法（展開溶媒：クロロホルム／酢酸エチル／メタノル＝１５／５／１）を二回行い、薄い黄色の固体を得た。収率：５４．７ｍｏｌ％。
構造確認は^１ＨＮＭＲで行った。電気化学的特性および熱特性を後記表１に示す。 (2) Synthesis of 1,3,5-tri [m- (4-isoquinolyl) phenyl] benzene (TmiQPhB)

In a four-necked flask, 1,3,5-tris (m-bromophenyl) benzene {1,3,5-tris (m-bromophenyl) benzene} (0.91 g, 1.68 mmol), 4-isoquinoline boric acid ( 4-isoquinolinone boronic acid (1.0 g, 5.78 mmol), tetrakis (triphenylphosphine) palladium [Pd (PPh ₃ ) ₄ ] (334 mg, 0.289 mmol), toluene / THF (1/1, 120 mL) and 2MK ₂ CO ₃ (40 mL) was added and reacted at 90 ° C. for 24 hours under a nitrogen stream to obtain 1,3,5-tri [m- (4-isoquinolyl) phenyl] benzene (TmiQPhB). After completion of the reaction, the reaction solution was poured into water, extracted with chloroform, and washed with saturated brine. It dehydrated with anhydrous magnesium sulfate and the solvent was removed by an evaporator.
Purification was performed twice by column chromatography (developing solvent: chloroform / ethyl acetate / methanol = 15/5/1) to obtain a pale yellow solid. Yield: 54.7 mol%.
The structure was confirmed by ¹ HNMR. The electrochemical characteristics and thermal characteristics are shown in Table 1 below.

四つ口フラスコに５−ブロモピリミジン（５−ｂｒｏｍｏｐｙｒｉｍｉｄｉｎｅ）（９．８１ｇ、６１．７ｍｍｏｌ）、３−クロロフェニルボロン酸（３−ｃｈｌｏｒｏｐｈｅｎｙｌｂｏｒｏｎｉｃ ａｃｉｄ）（９．６５ｇ、６１．７ｍｍｏｌ）、Ｐｄ（ＰＰｈ_３）_４（１．４８ｇ、１．２８ｍｍｏｌ）、トルエン／エタノール（９／２、２２０ｍＬ）と２ＭＫ_２ＣＯ_３（１２０ｍＬ）を入れて、窒素気流下９０℃で２４時間反応させ、５−（３−クロロフェニル）ピリミジン（ＣＰｈ５Ｐｍ）を得た。反応終了後、反応溶液を水に注ぎ、トルエンで抽出し、飽和食塩水で洗浄した。無水硫酸マグネシウムで脱水し、溶媒をエバポレーターで除去した。
精製はカラムクロマトグラフィー法（展開溶媒：ｎ−ヘキサン／酢酸エチル＝１／１）を行い、白い固体を得た。収率：９５．０ｍｏｌ％。
構造確認は^１ＨＮＭＲで行った。 Synthesis example 2
(1) Synthesis of 5- (3-chlorophenyl) pyrimidine (CPh5Pm)

In a four-necked flask, 5-bromopyrimidine (9.81 g, 61.7 mmol), 3-chlorophenylboronic acid (9.65 g, 61.7 mmol), Pd (PPh ₃ ) ₄ (1.48 g, 1.28 mmol), toluene / ethanol (9/2, 220 mL) and 2MK ₂ CO ₃ (120 mL) were allowed to react at 90 ° C. for 24 hours under a nitrogen stream, and 5- (3-chlorophenyl) ) Pyrimidine (CPh5Pm) was obtained. After completion of the reaction, the reaction solution was poured into water, extracted with toluene, and washed with saturated brine. It dehydrated with anhydrous magnesium sulfate and the solvent was removed by an evaporator.
Purification was performed by column chromatography (developing solvent: n-hexane / ethyl acetate = 1/1) to obtain a white solid. Yield: 95.0 mol%.
The structure was confirmed by ¹ HNMR.

四つ口フラスコにＣＰｈ５Ｐｍ（６．２６ｇ、３２．８ｍｍｏｌ）、ビス（ピナコラート）ジボロン｛ｂｉｓ（ｐｉｎａｃｏｌａｔｏ）ｄｉｂｏｒｏｎ｝（１０ｇ、３９．４ｍｍｏｌ）、酢酸カリウム（４．８３ｇ、４９．２ｍｍｏｌ）、ビス（ジベンジリデンアセトン）パラジウム（０）｛ｂｉｓ（ｄｉｂｅｎｚｙｌｉｄｅｎｅａｃｅｔｏｎｅ）ｐａｌｌａｄｉｕｍ（０）｝〔Ｐｄ（ｄｂａ）_２〕（５６６ｍｇ、０．９８４ｍｍｏｌ）、トリシクロヘキシルホスフィン（ｔｒｉｃｙｃｌｏｈｅｘｙｌｐｈｏｓｐｈｉｎｅ）（１．１０ｇ、３．９４ｍｍｏｌ）と無水１，４−ジオキサン（１５０ｍＬ）を入れて、窒素気流下８０℃で９６時間反応させ、５−｛３−（４，４，５，５−テトラメチル−１，３，２−ジオキサボラン−２−イル）フェニル｝ピリミジン（５ＰｍＰｈＤＯＢ）を得た。その後、反応溶液に水を注ぎ、トルエンで抽出し、飽和食塩水で洗浄した。無水硫酸マグネシウムで脱水し、溶媒をエバポレーターで除去した。
精製はカラムクロマトグラフィー法〔展開溶媒：ｎ−ヘキサン／酢酸エチル＝２／１（１回）；クロロホルム／酢酸エチル＝６／１（２回）〕を行い、薄い黄色の粘体を得た。収率：４６．５ｍｏｌ％。
構造確認は^１ＨＮＭＲで行った。 (2) Synthesis of 5- {3- (4,4,5,5-tetramethyl-1,3,2-dioxaboran-2-yl) phenyl} pyrimidine (5PmPhDOB)

In a four-necked flask, CPh5Pm (6.26 g, 32.8 mmol), bis (pinacolato) diboron {bis (pinacolato) diboron} (10 g, 39.4 mmol), potassium acetate (4.83 g, 49.2 mmol), bis ( Dibenzylideneacetone) palladium (0) {bis (dibenzylideneacetone) paladium (0)} [Pd (dba) ₂ ] (566 mg, 0.984 mmol), tricyclohexylphosphine (1.10 g, 3.94 mmol) and anhydrous 1,4-Dioxane (150 mL) was added, and the mixture was reacted at 80 ° C. for 96 hours under a nitrogen stream. 5- {3- (4,4,5,5-tetramethyl-1,3,2-dioxaborane-2- Il Phenyl} pyrimidine (5PmPhDOB). Thereafter, water was poured into the reaction solution, extracted with toluene, and washed with saturated brine. It dehydrated with anhydrous magnesium sulfate and the solvent was removed by an evaporator.
Purification was performed by column chromatography [developing solvent: n-hexane / ethyl acetate = 2/1 (once); chloroform / ethyl acetate = 6/1 (once)] to obtain a pale yellow viscous body. Yield: 46.5 mol%.
The structure was confirmed by ¹ HNMR.

四つ口フラスコに１，３，５−トリブロモベンゼン（１，３，５−ｔｒｉｂｒｏｍｏｂｅｎｚｅｎｅ）（０．９４４ｇ，３．０ｍｍｏｌ）、５−｛３−（４，４，５，５−テトラメチル−１，３，２−ジオキサボラン−２−イル）フェニル｝ピリミジン（５ＰｍＰｈＤＯＢ）（２．８５ｇ，１０．１ｍｍｏｌ）、Ｐｄ（ＰＰｈ_３）_４（５２０ｍｇ、０．４５ｍｍｏｌ）、トルエン／エタノール（３／１、１２０ｍＬ）と２ＭＫ_２ＣＯ_３（３０ｍＬ）を入れて、窒素気流下９０℃で２４時間反応させ、１，３，５−トリ〔ｍ−（５−ピリミジル）フェニル〕ベンゼン（Ｔｍ５ＰｍＰｈＢ）を得た。反応終了後、反応溶液を水に注ぎ、トルエンで抽出し、飽和食塩水で洗浄した。無水硫酸マグネシウムで脱水し、溶媒をエバポレーターで除去した。
精製はカラムクロマトグラフィー法（展開溶媒：クロロホルム／酢酸エチル＝１／１；酢酸エチル；クロロホルム／メタノール＝２５／１）を行い、ｎ−ヘキサンによる再結晶を行い白色の粉末を得た。収率：４０．０ｍｏｌ％。
構造確認は^１ＨＮＭＲで行った。電気化学的特性および熱特性を後記表１に示す。 (3) 1,3,5-tri [m-(5-pyrimidine d) phenyl] Synthesis benzene (Tm5PmPhB)

In a four-necked flask, 1,3,5-tribromobenzene (0.944 g, 3.0 mmol), 5- {3- (4,4,5,5-tetramethyl- 1,3,2-dioxaboran-2-yl) phenyl} pyrimidine (5PmPhDOB) (2.85 g, 10.1 mmol), Pd (PPh ₃ ) ₄ (520 mg, 0.45 mmol), toluene / ethanol (3/1, 120 mL) and 2MK ₂ CO ₃ (30 mL) were added and reacted at 90 ° C. for 24 hours under a nitrogen stream to obtain 1,3,5-tri [m- (5-pyrimidyl) phenyl] benzene (Tm5PmPhB). After completion of the reaction, the reaction solution was poured into water, extracted with toluene, and washed with saturated brine. It dehydrated with anhydrous magnesium sulfate and the solvent was removed by an evaporator.
Purification was performed by column chromatography (developing solvent: chloroform / ethyl acetate = 1/1; ethyl acetate; chloroform / methanol = 25/1) and recrystallized with n-hexane to obtain a white powder. Yield: 40.0 mol%.
The structure was confirmed by ¹ HNMR. The electrochemical characteristics and thermal characteristics are shown in Table 1 below.

Ｔｇ：二次転移温度、Ｔｍ：融点、Ｔｄ：分解温度、Ｅｇ：エネルギーギャップ、ＩＰ：イオン化ポテンシャル、Ｅａ：エレクトロアフィニティ（電子親和力）、ｎ．ｄ．：検出されず。
Ｔｇ（ガラス転移温度）については、ＤＳＣ（Ｄｉｆｆｉｒｅｎｔｉａｌ Ｓｃａｎｎｉｎｇ Ｃａｌｏｒｉｍｅｔｅｒ 示差熱量計）中にサンプルを加え、溶融させたものを急冷し、２〜３回繰り返すとガラス転移を表すカーブがチャート上に現れるので、そのカーブを接線で結び、その交点の温度をＴｇとして採用する。
Ｔｍ（融点）は、同じくＤＳＣにサンプルを加え、昇温していくと吸熱カーブが現れるのでその極大のところとの温度を読んで、その温度をＴｍとする。
Ｔｄ（分解温度）は、ＤＴＡ（Ｄｉｆｆｅｒｅｎｔｉａｌ ｔｈｅｒｍａｌ ａｎａｌｙｚｅｒ 示差熱分析装置）にサンプルを加え、加熱していくとサンプルが熱によって分解し、重量が減少しだす。その減少を開始しだしたところの温度を読んで、その温度をＴｄとする。
エネルギーギャップ（Ｅｇ）については、蒸着機で作成した薄膜を紫外−可視吸光度計で薄膜の吸収曲線を測定する。その薄膜の短波長側の立ち上がりの所に接線を引き、求まった交点の波長を次の式に代入し目的の値を求める。それによって得た値がＥｇになる。
Ｅｇ＝１２４０÷ｎｍ
例えば接線を引いて求めた値が４７０ｎｍだったとしたらこの時のＥｇの値は
Ｅｇ＝１２４０÷４７０＝２．６３（ｅＶ）
と言うことになる。
Ｉｐ（イオン化ポテンシャル）は、イオン化ポテンシャル測定装置（例えば理研計器ＡＣ−１）を使用して測定し、測定するサンプルがイオン化を開始しだしたところの電圧（ｅＶ）の値を読む。
Ｅａ（電子親和力）は、ＩｐからＥｇを引いた値である。
本明細書における波長に対する強度（ｉｎｔｅｎｓｉｔｙ ａ．ｕ．）の測定は、浜松ホトニクス社製ストリークカメラを用いて、クライオスタット中で４．２ｋにおいて測定した。

Tg: secondary transition temperature, Tm: melting point, Td: decomposition temperature, Eg: energy gap, IP: ionization potential, Ea: electroaffinity (electron affinity), n. d. : Not detected.
About Tg (glass transition temperature), a sample is added to DSC (Differential Scanning Calorimeter), the melted material is rapidly cooled, and a curve representing the glass transition appears on the chart when repeated 2-3 times. The curves are connected by a tangent line, and the temperature at the intersection is adopted as Tg.
As for Tm (melting point), an endothermic curve appears when a sample is added to the DSC and the temperature is raised.
As for Td (decomposition temperature), when a sample is added to DTA (Differential Thermal Analyzer) and heated, the sample is decomposed by heat and the weight starts to decrease. The temperature at which the decrease starts is read and the temperature is defined as Td.
Regarding the energy gap (Eg), an absorption curve of the thin film prepared with a vapor deposition machine is measured with an ultraviolet-visible absorptiometer. A tangent line is drawn at the rising edge of the thin film on the short wavelength side, and the target wavelength is obtained by substituting the obtained intersection wavelength into the following equation. The value obtained thereby becomes Eg.
Eg = 1240 ÷ nm
For example, if the value obtained by drawing a tangent is 470 nm, the value of Eg at this time is Eg = 1240 ÷ 470 = 2.63 (eV)
It will be said.
Ip (ionization potential) is measured using an ionization potential measuring apparatus (for example, Riken Keiki AC-1), and the value of the voltage (eV) at which the sample to be measured starts ionization is read.
Ea (electron affinity) is a value obtained by subtracting Eg from Ip.
Intensity au in this specification was measured at 4.2 k in a cryostat using a streak camera manufactured by Hamamatsu Photonics.

Example 1
Application structure to organic EL device using TmiQPhB as electron transport layer:
ITO / α-NPD (50 nm) / Alq ₃ (40 nm) / TmiQPhB (30 nm) / LiF (0.5 nm) / Al (100 nm); (Example 1 )
Physical property data of the element of this is shown in Table 2-4 a.

Ｔｕｒｎ ｏｎ ｖｏｌｔａｇｅ Ｍａｘ．は、最大発光開始電圧
Ｍａｘ．Ｐ．Ｅ．は、最大視感効率
Ｍａｘ．Ｃ．Ｅ．は、最大電流効率
Ｍａｘ．Ｑ．Ｅ．は、最大外部量子効率

Turn on voltage Max. Is the maximum light emission start voltage Max. P. E. Is the maximum luminous efficiency Max. C. E. Is the maximum current efficiency Max. Q. E. Is the maximum external quantum efficiency

ＰＥ：視感効率、ＱＥ：外部量子効率

PE: Luminous efficiency, QE: External quantum efficiency

¹ H NMR of 1,3,5-tri [m- (4-isoquinolyl) phenyl] benzene (TmiQPhB) is shown. Shows The ¹ HNMR of 1,3,5-tri [m-(5-pyrimidine d) phenyl] benzene (Tm5PmPhB). The PL intensity and EL intensity of 1,3,5-tri [m- (4-isoquinolyl) phenyl] benzene (TmiQPhB) are shown.

Claims (3)

1,3,5-triphenylbenzene derivative represented by the following general formula (1) .

[ Wherein , Ar ¹ represents a pyrimidinyl group or an isoquinolyl group. ] The organic electroluminescent device characterized by containing the claims 1 Symbol placement No 1,3,5 benzene derivatives. The organic electroluminescent device characterized by claims 1 Symbol placement No 1,3,5 benzene derivatives used as the electron transporting material.

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