JP5086608B2 - Novel di (phenanthroline) derivative, electron transport material comprising the same, and organic electroluminescence device including the same - Google Patents

Description

  The present invention relates to a novel di (phenanthroline) derivative, an electron transport material comprising the same, and an organic electroluminescence device including the same.

  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 (non Patent Document 3).

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）ピリジネート−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 1 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) pyridinate-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. For these phosphorescent materials, Alq ₃ [tris (8-hydroxyquinolinolato) aluminum] and BAlq ₂ [bis (2-methyl-8-hydroxyquinolinolato) (which are conventionally used for electron transport materials) ( 4-phenylphenoxy) aluminum] and the like are used, but 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 Appl. Phys. Lett 1999 75 (1) 4-7 Appl. Phys. Lett. 79, 2082 (2001) J. et al. Appl. Phys. 90 5048 (2001) Polyhedron 23 (2004) 419-428

  An object of the present invention is to provide a novel di (phenanthroline) derivative that has a high electron transporting property and can form a highly efficient blue fluorescent device, an electron transport material comprising the same, and an organic electroluminescent device including the same.

（式中、Ｑは

よりなる群から選ばれた基であり、Ｒ^１〜Ｒ^７およびＲ ^２２ 〜Ｒ ^６２ は水素および炭素数１〜６の直鎖または分岐のアルキル基よりなる群からそれぞれ独立して選ばれた基である）
で示されるジ（フェナントロリン）誘導体に関する。
本発明の第２は、請求項１記載のジ（フェナントロリン）誘導体よりなる電子輸送材料に関する。
本発明の第３は、請求項１記載のジ（フェナントロリン）誘導体を含む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 is the following general formula (1)

(Where Q is

R ^{1 to} R ⁷ and R ^{22 to} R ⁶² are groups independently selected from the group consisting of hydrogen and a linear or branched alkyl group having 1 to 6 carbon atoms. Is)
It is related with the di (phenanthroline) derivative shown by these.
The second of the present invention relates to an electron transport material comprising the di (phenanthroline) derivative according to claim 1.
3rd of this invention is related with the organic electroluminescent element containing the di (phenanthroline) derivative of Claim 1.

（式中、Ｑは前記〔化８〕で示される基であり、ＥｔＯＨはエチルアルコールである。）
また前記Ｒ^１〜Ｒ^７およびＲ ^２２ 〜Ｒ ^６２ における炭素数１〜６の直鎖または分岐のアルキル基としては、メチル、エチル、プロピル、イソプロピル、ｎ−ブチル、イソブチル、ｔ−ブチル、ヘプチル、イソヘプチル、ｎ−ヘキシル等を挙げることができる。 The di (phenanthroline) derivative of the present invention can be produced by the following reaction.

(In the formula, Q is a group represented by the above [Chemical Formula 8], and EtOH is ethyl alcohol .)
Further Examples of the linear or branched alkyl group having 1 to 6 carbon atoms in R ¹ to R ⁷ and R ²² to R ^62, methyl, ethyl, propyl, isopropyl, n- butyl, isobutyl, t- butyl, heptyl, Examples include isoheptyl and n-hexyl.

Specific examples of the compound of the present invention are shown below.

The di (phenanthroline) derivative of the present invention has high electron transport performance. Therefore, it can be used as an electron injection material and an electron transport material.
When the di (phenanthroline) derivative of the present invention is used in an organic electroluminescence device, it can be used in combination with a suitable light emitting material (dopant).
When the di (phenanthroline) derivative of the present invention is used for an electron transport layer, the compound of the present invention can be used as an electron injection material or an electron transport material. It can also be used in combination with other electron transport materials.

  Next, the organic electroluminescence element of the present invention will be described. The organic electroluminescence device of the present invention is a device in which a single layer or a multilayer organic compound is laminated between an anode and a cathode, and at least one layer of the organic compound layer contains the di (phenanthroline) derivative of the present invention. When the organic electroluminescence element is a single layer, a light emitting layer is provided between the anode and the cathode. The light emitting layer contains a light emitting material and may contain a hole injecting material or an electron injecting material for the purpose of transporting holes injected from the anode or electrons injected from the cathode to the light emitting material. . Examples of the configuration of the multi-layer organic electroluminescence element include, for example, ITO / hole transport layer / light-emitting layer / electron transport layer / cathode, ITO / hole injection layer / hole transport layer / light-emitting layer / electron transport layer / cathode, ITO / Hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode, ITO / hole transport layer / light emitting layer / hole block layer / electron transport layer / cathode, ITO / hole injection layer / hole transport layer / light emitting layer / hole Block layer / electron transport layer / cathode, ITO / hole transport layer / light emitting layer / hole block layer / electron transport layer / electron injection layer / cathode, ITO / hole injection layer / hole transport layer / light emitting layer / hole block layer / electron Examples thereof include those laminated in a multilayer structure such as a transport layer / electron injection layer / cathode. Moreover, you may have a sealing layer on a cathode as needed.

Each of the hole transport layer, the electron transport layer, and the light emitting layer may have a single layer structure or a multilayer structure. In addition, the hole transport layer and the electron transport layer should be provided separately with a layer responsible for the injection function (hole injection layer and electron injection layer) and a layer responsible for the transport function (hole transport layer and electron transport layer). You can also.
The organic electroluminescence element of the present invention is not limited to the above configuration example, and can have various configurations. If necessary, a layer in which a hole transport layer component and a light emitting layer component or an electron transport layer component and a light emitting layer component are mixed may be provided.

Hereinafter, the constituent elements of the organic electroluminescence element of the present invention will be described in detail by taking as an example an element configuration comprising an anode / hole transport layer / light emitting layer / electron transport layer / cathode. The organic electroluminescence device of the present invention is preferably supported on a substrate.
There is no restriction | limiting in particular about the raw material of a board | substrate, What is necessary is just used for the conventional organic electroluminescent element, For example, what consists of glass, quartz glass, a transparent plastic etc. can be used.

As an anode of the organic electroluminescence device of the present invention, an electrode material may be a single metal having a high work function (4 eV or more), an alloy of metals having a high work function (4 eV or more), a conductive substance, or a mixture thereof. preferable. Specific examples of such electrode materials include metals such as gold, silver, and copper, conductive transparent materials such as ITO (indium-tin oxide), tin oxide (SnO ₂ ), and zinc oxide (ZnO), polypyrrole, and polythiophene. Examples thereof include conductive polymer materials such as For the anode, these electrode materials can be formed on the substrate by a method such as vapor deposition, sputtering, or coating. The sheet electrical resistance of the anode is preferably several hundred Ω / cm ² or less. The thickness of the anode depends on the material, but is generally about 5 to 1,000 nm, preferably 10 to 500 nm.

As the cathode, an electrode material is preferably a single metal having a small work function (4 eV or less), an alloy of metals having a small work function (4 eV or less), a conductive substance, or a mixture thereof. Specific examples of such electrode materials include lithium, lithium-indium alloy, sodium, sodium-potassium alloy, magnesium, magnesium-silver alloy, magnesium-indium alloy, aluminum, aluminum-lithium alloy, and aluminum-magnesium alloy. Can be mentioned. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. The sheet electrical resistance of the cathode is preferably several hundred Ω / cm ² or less. The thickness of the cathode depends on the material, but is generally about 5 to 1,000 nm, preferably 10 to 500 nm. In order to efficiently extract light emitted from the organic electroluminescence device of the present invention, at least one of the anode and the cathode is preferably transparent or translucent.

The hole transport layer of the organic electroluminescence device of the present invention is made of a hole transfer compound and has a function of transferring holes injected from the anode to the light emitting layer. When a hole transport compound is disposed between two electrodes to which an electric field is applied and holes are injected from the anode, a hole transport material having a hole mobility of at least 10 ⁻⁶ cm ² / V · second or more is obtained. preferable. The hole transport material used for the hole transport layer of the organic electroluminescence device of the present invention is not particularly limited as long as it has the above-mentioned preferable properties. It is possible to select and use any of the materials conventionally used as hole charge injection / transport materials in photoconductive materials and known materials used for the hole transport layer of organic electroluminescent devices. it can.

  Examples of the hole transfer material include phthalocyanine derivatives such as copper phthalocyanine, N, N, N ′, N′-tetraphenyl-1,4-phenylenediamine, and N, N′-di (m-tolyl) -N. , N′-diphenyl-4,4′-diaminobiphenyl (TPD), N, N′-di (1-naphthyl) -N, N′-diphenyl-4,4′-diaminobiphenyl (α-NPD), etc. And triarylamine derivatives, polyphenylenediamine derivatives, polythiophene derivatives, and water-soluble PEDOT: PSS (polyethylenedioxathiophene-polystyrenesulfonic acid). The hole transport layer may be composed of one or more of these other hole transport compounds, and a hole transport layer composed of a compound different from the hole transport material is laminated. It may be a thing.

正孔輸送材料としては、下記化学式に示すＴＰＤ、ＤＴＡＳＩ、ｍ−ＤＴＡＴＰＢなどを挙げることができる。

Examples of the hole injection material include PEDOT: PSS (polymer mixture) and DNTPD represented by the following chemical formula.

Examples of the hole transport material include TPD, DTASI, and m-DTATPB represented by the following chemical formula.

The light emitting material of the light emitting layer of the organic electroluminescence device of the present invention is not particularly limited, and any one of conventionally known compounds can be selected and used.
Examples of the light-emitting material include perylene derivatives, naphthacene derivatives, quinacridone derivatives, coumarin derivatives (eg, coumarin 1, coumarin 540, coumarin 545, etc.), pyran derivatives (eg, DCM-1, DCM-2, DCJTB, etc.), organometallic complexes {Tris Fluorescent materials such as (8-hydroxyquinolinolato) aluminum (Alq ₃ ) and tris (4-methyl-8-hydroxyquinolinolato) aluminum (Almq ₃ ) and bis [2- (4,6-difluorophenyl) pyridyl -N, C2 '] iridium (III) picorylate (FIrpic), tris {1- [4- (trifluoromethyl) phenyl] -1H-pyrazolate, N, C2'} iridium (III) (Irtfmpppz ₃ ), bis [ 2- (4 ', 6'-difluorophenyl) pyridinate-N C2 '] tetrakis (1-pyrazolyl) borate (FIr6), tris (2-phenylpyridinato-), and the like iridium _{(III) [Ir (PPy)} 3] phosphorescent material such}.

The light-emitting layer can also be formed of a host material and a guest material (dopant) [Appl. Phys. Lett. 65 3610 (1989)]. In particular, when a phosphorescent material is used for the light emitting layer, it is necessary to use a host material, and the host material used at this time is 4,4'-di (N-carbazolyl) -1,1'-biphenyl (CBP). 1,2-di (N-carbazolyl) benzene, 2,2′-di [4 ″-(N-carbazolyl) phenyl] -1,1′-biphenyl (4CzPBP) and the like.
The guest material is preferably 0.01 to 40% by weight, more preferably 0.1 to 20% by weight, based on the host material. Examples of guest materials include conventionally known FIrpic (Chemical Formula 4), Ir (PPy) ₃ (Chemical Formula 3), and Fir6 (Chemical Formula 6).

  As the material for the electron transport layer of the organic electroluminescence device of the present invention, the heteroaryl compound of the present invention is preferred. Although this thing can be used independently, you may use together with another electron transport material.

  The organic electroluminescent device of the present invention may further include an electron injection layer composed of an insulator between the cathode and the organic layer for the purpose of further improving the electron injection property. As the conductor used here, it is preferable to use at least one metal compound selected from alkali metal halides and alkaline earth metal halides. Examples of the alkali metal halide include lithium fluoride, sodium fluoride, potassium fluoride, cesium fluoride, and lithium chloride. Examples of the alkaline earth metal halide include magnesium fluoride, calcium fluoride, barium fluoride, and strontium fluoride.

  The method for forming the hole transport layer and the light emitting layer is not particularly limited. For example, a dry film forming method (for example, a vacuum deposition method, an ionization vapor deposition method, etc.) or a wet film forming method [a solution coating method (for example, a spin coating method, a casting method, an ink jet method, etc.)] can be used. As a method for forming the electron transport layer of the di (phenanthroline) derivative of the present invention, a dry film forming method (for example, a vacuum evaporation method or an ionization evaporation method) is preferable. In addition, the above-described film formation method may be used in combination for manufacturing the element.

When forming each layer such as a hole transport layer, a light emitting layer, and an electron transport layer by a vacuum deposition method, the vacuum deposition conditions are not particularly limited. Usually, a boat temperature (deposition source temperature) of about 50 to 500 ° C. under a vacuum of about 10 ⁻⁴ Pa or less, a substrate temperature of about −50 to 300 ° C., and 0.01 to 50 nm / sec. Vapor deposition is preferred. When forming each layer of a positive hole transport layer, a light emitting layer, and an electron carrying layer using a some compound, it is preferable to co-evaporate each boat which put the compound, temperature-controlling each.

  When forming the hole transport layer and the light emitting layer by a solvent coating method, the components constituting each layer are dissolved or dispersed in a solvent to obtain a coating solution. Solvents include hydrocarbon solvents (eg, heptane, toluene, xylene, cyclohexane, etc.), ketone solvents (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), halogen solvents (eg, dichloromethane, chloroform, chlorobenzene, dichlorobenzene, etc.) ), Ester solvents (eg, ethyl acetate, butyl acetate, etc.), alcohol solvents (eg, methanol, ethanol, butanol, methyl cellosolve, ethyl cellosolve, etc.), ether solvents (eg, dibutyl ether, tetrahydrofuran, 1,4-dioxane, 1,2-dimethoxyethane and the like), aprotic solvents (for example, N, N'-dimethylacetamide, dimethyl sulfoxide and the like), water and the like. The solvent may be used alone, or a plurality of solvents may be used in combination.

  The thickness of each layer such as the hole transport layer, the light emitting layer, and the electron transport layer is not particularly limited, but is usually 5 to 5,000 nm.

  The organic electroluminescence device of the present invention can be protected by providing a protective layer (sealing layer) for the purpose of blocking contact with oxygen, moisture, or the like, or by encapsulating the device in an inert substance. Examples of the inert substance include paraffin, silicon oil, and fluorocarbon. Examples of the material used for the protective layer include fluorine resin, epoxy resin, silicone resin, polyester, polycarbonate, and photocurable resin.

  The organic electroluminescence device of the present invention can be used as a normal DC drive device. When a DC voltage is applied, light emission is observed when a voltage of about 1.5 to 20 V is applied with the positive polarity of the anode and the negative polarity of the cathode. Moreover, the organic electroluminescent element of this invention can be used also as an element of an alternating current drive. When an AC voltage is applied, light is emitted when the anode is in a positive state and the cathode is in a negative state. The organic electroluminescence device of the present invention includes, for example, a flat light emitter such as an electrophotographic photosensitive member and a flat panel display, a copying machine, a printer, a backlight of a liquid crystal display, a light source such as an instrument, various light emitting devices, various display devices, and various signs. It can be used for various sensors and various accessories.

20 to 33 show preferred examples of the organic electroluminescence element of the present invention.
FIG. 20 is a cross-sectional view showing an example of the organic electroluminescence element of the present invention. FIG. 20 shows a configuration in which an anode 2, a light emitting layer 3 and a cathode 4 are sequentially provided on a substrate 1. The light-emitting element used here is useful when it has a single hole-transporting property, electron-transporting property, and light-emitting function, or a mixture of compounds having the respective functions. It is.
FIG. 21 is a cross-sectional view showing another example of the organic electroluminescence element of the present invention. FIG. 21 shows a configuration in which an anode 2, a hole transport layer 5, a light emitting layer 3, and a cathode 4 are sequentially provided on a substrate 1. In this case, the light emitting layer is useful when it has an electron transporting function.
FIG. 22 is a cross-sectional view showing another example of the organic electroluminescence element of the present invention. FIG. 22 shows a structure in which an anode 2, a light emitting layer 3, an electron transport layer 6 and a cathode 4 are sequentially provided on a substrate 1. In this case, the light emitting layer is useful when it has a hole transporting function.

FIG. 23 is a cross-sectional view showing another example of the organic electroluminescence element of the present invention. FIG. 23 shows a structure in which an anode 2, a hole transport layer 5, a light emitting layer 3, an electron transport layer 6 and a cathode 4 are sequentially provided on a substrate 1. This separates the functions of carrier transport and light emission, and the degree of freedom in material selection increases, so that the efficiency of light emission and the degree of freedom in light emission color increase.
FIG. 24 is a cross-sectional view showing another example of the organic electroluminescence element of the present invention. FIG. 24 shows a configuration in which an anode 2, a hole injection layer 7, a hole transport layer 5, a light emitting layer 3, an electron transport layer 6 and a cathode 4 are sequentially provided on a substrate 1. In this case, the provision of the hole injection layer 7 improves the adhesion between the anode 2 and the hole transport layer 5, improves the injection of holes from the anode, and is effective in driving the light emitting element at a low voltage.

FIG. 25 is a cross-sectional view showing another example of the organic electroluminescence element of the present invention. FIG. 25 shows a structure in which an anode 2, a hole transport layer 5, a light emitting layer 3, an electron transport layer 6, an electron injection layer 8 and a cathode 4 are sequentially provided on a substrate 1. In this case, injection of electrons from the cathode 4 is improved, which is effective for driving the light emitting element at a low voltage.
FIG. 26 is a cross-sectional view showing another example of the organic electroluminescence element of the present invention. FIG. 26 shows a structure in which an anode 2, a hole injection layer 7, a hole transport layer 5, a light emitting layer 3, an electron transport layer 6, an electron injection layer 8 and a cathode 4 are sequentially provided on a substrate 1. In this case, injection of holes from the anode 2 is improved and injection of electrons from the cathode 4 is improved, which is the most effective for low voltage driving.

27 to 33 are cross-sectional views of a device in which a hole blocking layer is inserted. The hole blocking layer has an effect of preventing holes injected from the anode or excitons generated by recombination in the light emitting layer 3 from escaping to the cathode 4, and is effective in improving the light emission efficiency of the electroluminescence element. is there. The hole blocking layer 9 can be inserted between the light emitting layer 3 and the cathode 4, between the light emitting layer 3 and the electron transport layer 6, or between the light emitting layer 3 and the electron injection layer 8. More preferred is between the light emitting layer 3 and the electron transport layer 6.
27 to 33, each of the hole transport layer 5, the hole injection layer 7, the electron transport layer 6, the electron injection layer 8, the light emitting layer 3, and the hole blocking layer 9 has a single layer structure. A multilayer structure may be used.

  20 to 33 are basic device configurations to the last, and the configuration of the organic electroluminescence device using the compound of the present invention is not limited thereto.

Examples of the electron injecting material used for the electron injecting layer include the compounds according to Japanese Patent Application No. 2006-292032 of the applicant, for example, the following compound group.

The compound of the present invention has a very high electron mobility compared to a conventional electron transfer agent such as Alq ₃ . Therefore, the light emission start voltage can be reduced by 1 V or more, and the current density in unit voltage is large. Therefore, by using the electron transport material of the present invention, the device can be driven at a low voltage, which contributes to a longer life of the device.

  Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited thereto.

温度計、冷却管、Ｎ_２ガス導入管、撹拌機のついた３００ｍｌの４つ口丸底フラスコに８−アミノ−７−アルデヒドキノリン（８−Ａｍｉｎｏ−７−ａｌｄｅｈｙｄｅｑｕｉｎｏｌｉｎｅ）１．６４ｇ（９．５２ｍｍｏｌ）、２，６−ビス（３，３′−ジアセチルフェニル）ピリジン〔２，６−Ｂｉｓ（３，３′−ｄｉａｃｅｔｙｌｐｈｅｎｙｌ）ｐｙｒｉｄｉｎｅ〕１．５ｇ（４．７６ｍｍｏｌ）、エタノール１８０ｍｌおよび飽和水酸化カリウム（２．０ｇ）のエタノール溶液２０ｍｌを加え、Ｎ_２気流下還流温度で一晩反応した。反応後室温まで冷却し、クロロホルムで抽出し、食塩水で三回洗った。有機層を硫酸マグネシウムで乾燥し、得られた有機層は減圧下で溶媒回収を行い粗精製物を得た。この粗生成物をシリカゲルカラムクロマトグラフ（展開溶媒クロロホルム：酢酸エチル＝１：１）で精製し、目的物１．８ｇ（収率６４％）を得た。 Example 1
Synthesis of 2,6-bis [(3-phenanthrolin-2-yl) phenyl] pyridine {2,6-Bis [(3-phenanthrolin-2-yl) phenyl]} (BPnPhPy)

1.64 g (9.52 mmol) of 8-amino-7-aldehydequinoline in a 300 ml four-necked round bottom flask equipped with a thermometer, condenser, N ₂ gas inlet tube, and stirrer ), 2,6-bis (3,3′-diacetylphenyl) pyridine [2,6-Bis (3,3′-diacetylphenyl) pyridine], 1.5 g (4.76 mmol), ethanol 180 ml and saturated potassium hydroxide ( was added an ethanol solution 20ml of 2.0 g), it was reacted overnight under _{N 2} stream at reflux temperature. After the reaction, the mixture was cooled to room temperature, extracted with chloroform, and washed three times with brine. The organic layer was dried over magnesium sulfate, and the resulting organic layer was subjected to solvent recovery under reduced pressure to obtain a crude product. The crude product was purified by silica gel column chromatography (developing solvent: chloroform: ethyl acetate = 1: 1) to obtain 1.8 g (yield 64%) of the target product.

温度計、冷却管、Ｎ_２ガス導入管、撹拌機のついた３００ｍｌの４つ口丸底フラスコに８−アミノ−７−アルデヒドキノリン（８−Ａｍｉｎｏ−７−ａｌｄｅｈｙｄｅｑｕｉｎｏｌｉｎｅ）１．５ｇ（８．８ｍｍｏｌ）、１，３−ビス（６，６′−ジアセチルピリジル−２−２′−イル）ベンゼン〔１，３−Ｂｉｓ（６，６′−ｄｉａｃｅｔｙｌｐｙｒｉｄｙ−２−２′−ｙｌ）ｂｅｎｚｅｎｅ〕１．４ｇ（４．４ｍｍｏｌ）、エタノール１００ｍｌおよび飽和水酸化カリウム（１．０ｇ）エタノール溶液２０ｍｌを加え、Ｎ_２気流下還流温度で一晩反応した。反応後室温まで冷却し、クロロホルムで抽出し、食塩水で三回洗った。有機層を硫酸マグネシウムで乾燥し、得られた有機層は減圧下で溶媒回収を行い粗精製物を得た。これを２００ｍｌのエタノールで分散洗浄し、減圧ろ過により、目的物１．９ｇ（収率７３％）を得た。 Example 2
1,3-bis [(6-phenanthrolin-2-yl) pyridyl-2-yl] benzene {1,3-Bis [(6-phenanthrolin-2-yl) pyridine-2-yl] benzene} (BPyPnB ) Synthesis

In a 300 ml four-necked round bottom flask equipped with a thermometer, a condenser tube, an N ₂ gas introduction tube, and a stirrer, 1.5 g (8.8 mmol) of 8-amino-7-aldehydequinoline (8.8 mmol) ), 1,3-bis (6,6′-diacetylpyridyl-2-2′-yl) benzene [1,3-Bis (6,6′-diacylpyridine-2-2′-yl) benzene] 1.4 g (4.4 mmol), ethanol 100ml and saturated potassium hydroxide (1.0 g) in ethanol 20ml was added and reacted overnight at a stream of _{N 2} at reflux temperature. After the reaction, the mixture was cooled to room temperature, extracted with chloroform, and washed three times with brine. The organic layer was dried over magnesium sulfate, and the resulting organic layer was subjected to solvent recovery under reduced pressure to obtain a crude product. This was dispersed and washed with 200 ml of ethanol, and 1.9 g (yield 73%) of the target product was obtained by filtration under reduced pressure.

温度計、冷却管、Ｎ_２ガス導入管、撹拌機のついた３００ｍｌの４つ口丸底フラスコに８−アミノ−７−アルデヒドキノリン２．５ｇ（１４．２ｍｍｏｌ）、４，６−ビス（３′−アセチルフェニル）ピリミジン２．２ｇ（６．９５ｍｍｏｌ）、エタノール１４０ｍｌおよび飽和水酸化カリウム（１．０ｇ）エタノール溶液２０ｍｌを加え、Ｎ_２気流下還流温度で一晩反応した。反応後室温まで冷却し、クロロホルムで抽出し、食塩水で三回洗った。有機層を硫酸マグネシウムで乾燥し、得られた有機層を減圧下で溶媒回収を行い粗精製物を得た。この粗精製物をシリカゲルカラムクロマトグラフ（展開溶媒クロロホルム：酢酸エチル：メタノール＝２０：２：１）で精製し、目的物２．４ｇ（収率５９％）を得た。 Example 3
Synthesis of 4,6-bis (3-phenanthro-2-ylphenyl) pyrimidine (PmDPhPn)

To a 300 ml four-necked round bottom flask equipped with a thermometer, a condenser tube, an N ₂ gas introduction tube, and a stirrer, 2.5 g (14.2 mmol) of 8-amino-7-aldehyde quinoline, 4,6-bis (3 '-Acetylphenyl) pyrimidine (2.2 g, 6.95 mmol), ethanol (140 ml) and saturated potassium hydroxide (1.0 g) in ethanol (20 ml) were added, and the mixture was reacted overnight at reflux temperature in a N ₂ stream. After the reaction, the mixture was cooled to room temperature, extracted with chloroform, and washed three times with brine. The organic layer was dried over magnesium sulfate, and the resulting organic layer was subjected to solvent recovery under reduced pressure to obtain a crude product. This crude product was purified by silica gel column chromatography (developing solvent: chloroform: ethyl acetate: methanol = 20: 2: 1) to obtain 2.4 g (yield 59%) of the desired product.

温度計、冷却管、Ｎ_２ガス導入管、撹拌機のついた３００ｍｌの４つ口丸底フラスコに８−アミノ−７−アルデヒドキノリン１．９ｇ（１０．９ｍｍｏｌ）、２−メチル−４，６−ビス（３′−アセチルフェニル）ピリミジン１．８ｇ（５．４５ｍｍｏｌ）、エタノール１００ｍｌおよび飽和水酸化カリウム（１．０ｇ）のエタノール溶液２０ｍｌを加え、Ｎ_２気流下還流温度で一晩反応した。反応後室温まで冷却し、クロロホルムで抽出し、食塩水で三回洗った。有機層を硫酸マグネシウムで乾燥し、得られた有機層を減圧下で溶媒回収を行い粗精製物を得た。これをシリカゲルカラムクロマトグラフ（展開溶媒クロロホルム：酢酸エチル：メタノール＝１０：１０：２）で精製し、目的物２．３ｇ（収率７０％）を得た。 Example 4
Synthesis of 2-methyl-4,6-bis (3-phenanthro-2-ylphenyl) pyrimidine (MPmDPhPn)

In a 300 ml four-necked round bottom flask equipped with a thermometer, a condenser tube, an N ₂ gas introduction tube, and a stirrer, 1.9 g (10.9 mmol) of 8-amino-7-aldehyde quinoline, 2-methyl-4,6 - bis (3'-acetylphenyl) pyrimidine 1.8 g (5.45 mmol), ethanol solution 20ml of ethanol 100ml and saturated potassium hydroxide (1.0 g) was added and reacted overnight at a stream of _{N 2} at reflux temperature. After the reaction, the mixture was cooled to room temperature, extracted with chloroform, and washed three times with brine. The organic layer was dried over magnesium sulfate, and the resulting organic layer was subjected to solvent recovery under reduced pressure to obtain a crude product. This was purified by silica gel column chromatography (developing solvent chloroform: ethyl acetate: methanol = 10: 10: 2) to obtain 2.3 g (yield 70%) of the desired product.

2,6-bis [(3-phenanthrolin-2-yl) phenyl] pyridine (BPnPhPy) obtained in Example 1 ,
1,3-bis [(6-phenanthrolin-2-yl) pyridyl-2-yl] benzene (BPyPnB) obtained in Example 2 ;
2-Methyl-4,6-bis (3-phenanthro-2-ylphenyl) pyrimidine (MPmDPhPn) obtained in Example 4
The electrochemical characteristics and thermal characteristics are shown in Table 1 below, and the UV spectrum and PL spectrum are shown in FIGS.

Td: decomposition temperature, Tg: secondary transition temperature, Tm: melting point, Ip: ionization potential, Eg: energy gap, Ea: electroaffinity (electron affinity), n. d. : Not detected.
As for Tg (secondary transition temperature), a sample is added to DSC (Differential Scanning Calorimeter), the melted sample is rapidly cooled, and a curve representing the glass transition appears on the chart when repeated 2-3 times. The curves are connected by tangent lines, 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, so the temperature at the maximum is read and the temperature is defined as Tm.
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 wavelength W (nm) at the obtained intersection is substituted into the following equation to obtain the target value. The value obtained thereby becomes Eg.
Eg = 1240 ÷ W
For example, if the value W (nm) obtained by drawing a tangent is 470 nm, the value of Eg at this time is Eg = 1240 ÷ 470 = 2.63 (eV)
Would 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 4.2K in a cryostat using a streak camera manufactured by Hamamatsu Photonics.

Examples 5-6 , Comparative Example 1
2,6-bis [(3-phenanthrolin-2-yl) phenyl] pyridine (BPnPhPy) obtained in Example 1 ,
The following organic EL device was produced using 1,3-bis [(6-phenanthrolin-2-yl) pyridyl-2-yl] benzene (BPyPnB) obtained in Example 2 .

<Configuration of organic EL element>
Comparative Example 1: ITO / α-NPD (50 nm) / Alq ₃ (70 nm) / LiF (0.5 nm) / Al
Example 5 : ITO / α-NPD (50 nm) / Alq ₃ (40 nm) / BPnPhPy (30 nm) / LiF (0.5 nm) / Al
Example 6 : ITO / α-NPD (50 nm) / Alq ₃ (40 nm) / BPyPnB (30 nm) / LiF (0.5 nm) / Al

また、実施例５〜６、比較例１の
電流密度−電圧特性を図５に、
輝度 −電圧特性を図６に、
電流効率−電圧特性を図７に、
ＥＬスペクトル を図８に示す。 The characteristics of the organic EL element are shown in Table 2 below.

Further, the current density-voltage characteristics of Examples 5 to 6 and Comparative Example 1 are shown in FIG.
The luminance-voltage characteristics are shown in FIG.
Figure 7 shows the current efficiency vs. voltage characteristics.
The EL spectrum is shown in FIG.

Ｂｕｆｆｅｒは、ホール注入層を指す。 Examples 7-8
2,6-bis [(3-phenanthrolin-2-yl) phenyl] pyridine (BPnPhPy) obtained in Example 1 ,
The following organic EL device was produced using 1,3-bis [(6-phenanthrolin-2-yl) pyridyl-2-yl] benzene (BPyPnB) obtained in Example 2 .

<Configuration of organic EL element>
Example 7 : ITO / Buffer (20 nm) / α-NPD (20 nm) / TBADN: 4% Sty-NPD (30 nm) / BPnPhPy (40 nm) / LiF (0.5 nm) / Al
Example 8 : ITO / Buffer (20 nm) / α-NPD (20 nm) / TBADN: 4% Sty-NPD (30 nm) / BPyPnB (40 nm) / LiF (0.5 nm) / Al

Buffer refers to a hole injection layer.

また、これらの素子の
電流密度−電圧特性を図９に、
輝度 −電圧特性を図１０に、
視感効率−電圧特性を図１１に、
電流効率−電圧特性を図１２に、
電流効率−輝度特性を図１３に、
ＥＬスペクトル を図１４に
示す。 The characteristics of the organic EL element are shown in Tables 3 and 4 below.

The current density-voltage characteristics of these elements are shown in FIG.
The luminance-voltage characteristics are shown in FIG.
The luminous efficiency vs. voltage characteristics are shown in FIG.
The current efficiency vs. voltage characteristics are shown in FIG.
The current efficiency-luminance characteristics are shown in FIG.
The EL spectrum is shown in FIG.

Example 9
An organic EL device was prepared using 2-methyl-4,6-bis (3-phenanthro-2-ylphenyl) pyrimidine (MPmDPhPn) obtained in Example 4 , and the organic EL devices of Comparative Example 1 and Example 5 were used. And its performance was compared.

<Configuration of organic EL element>
Comparative Example 1: ITO / α-NPD (50 nm) / Alq ₃ (70 nm) / LiF (0.5 nm) / Al
Example 5 : ITO / α-NPD (50 nm) / Alq ₃ (40 nm) / BPnPhPy (30 nm) / LiF (0.5 nm) / Al
Example 9 : ITO / α-NPD (50 nm) / Alq ₃ (40 nm) / MPmDPhPn (30 nm) / LiF (0.5 nm) / Al
The current density-voltage characteristics of these elements are shown in FIG.
The luminance-voltage characteristics are shown in FIG.
The luminous efficiency vs. voltage characteristics are shown in FIG.
The current efficiency vs. voltage characteristics are shown in FIG.
The EL spectrum is shown in FIG.

The characteristics of the organic EL element is shown in Table 5 below.

The resulting 2,6-bis in Example 1 [(3-phenanthroline-2-yl) phenyl] pyridine (BPnPhPy), obtained 1,3-bis in Example 2 [(6-phenanthroline 2-yl) pyridyl-2-yl] benzene (BPyPnB). The resulting 2,6-bis in Example 1 [(3-phenanthroline-2-yl) phenyl] pyridine (BPnPhPy), obtained 1,3-bis in Example 2 [(6-phenanthroline The respective PL spectra of -2-yl) pyridyl-2-yl] benzene (BPyPnB) are shown. Obtained in Example 1 2,6-bis [(3-phenanthroline-2-yl) phenyl] pyridine (BPnPhPy) and obtained in Example 4 2-methyl-4,6-bis (3- The respective UV spectra of phenanthro-2-ylphenyl) pyrimidine (MPmDPhPn) are shown. Obtained in Example 1 2,6-bis [(3-phenanthroline-2-yl) phenyl] pyridine (BPnPhPy) and obtained in Example 4 2-methyl-4,6-bis (3- The respective PL spectra of phenanthro-2-ylphenyl) pyrimidine (MPmDPhPn) are shown. The current density-voltage characteristics of the organic EL elements of Examples 5 to 6 and Comparative Example 1 are shown. The luminance-voltage characteristics of the organic EL elements of Examples 5 to 6 and Comparative Example 1 are shown. The current efficiency-voltage characteristics of the organic EL elements of Examples 5 to 6 and Comparative Example 1 are shown. The EL spectra of the organic EL elements of Examples 5 to 6 and Comparative Example 1 are shown. Each current density-voltage characteristic of the organic EL element of Examples 7-8 is shown. The luminance-voltage characteristics of the organic EL elements of Examples 7 to 8 are shown. Each luminous efficiency-voltage characteristic of the organic EL element of Examples 7-8 is shown. Each current efficiency-voltage characteristic of the organic EL element of Examples 7-8 is shown. The current efficiency-luminance characteristics of each of the organic EL elements of Examples 7 to 8 are shown. Each EL spectrum of the organic EL element of Examples 7-8 is shown. The current density-voltage characteristics of the organic EL elements of Example 5 , Example 9 and Comparative Example 1 are shown. The luminance-voltage characteristics of the organic EL elements of Example 5 , Example 9 and Comparative Example 1 are shown. The luminous efficiency-voltage characteristics of the organic EL elements of Example 5 , Example 9 and Comparative Example 1 are shown. The current efficiency-voltage characteristics of the organic EL elements of Example 5 , Example 9 and Comparative Example 1 are shown. Each EL spectrum of the organic EL element of Example 5 , Example 9, and Comparative Example 1 is shown. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. Sectional drawing which shows an example of the organic electroluminescent element in this invention. The data relating to “TrPhDPn” in FIGS. 1, 2, and 5 to 14 is related to the embodiment deleted by the correction, and is not related to the present invention.

1 Substrate 2 Anode (ITO)
3 Light emitting layer 4 Cathode 5 Hole transport layer (hole transport layer)
6 Electron transport layer 7 Hole injection layer (hole injection layer)
8 Electron injection layer 9 Hole blocking layer (hole blocking layer)

Claims (3)

The following general formula (1)

(Where Q is

R ^{1 to} R ⁷ and R ^{22 to} R ⁶² are groups independently selected from the group consisting of hydrogen and a linear or branched alkyl group having 1 to 6 carbon atoms. Is)
A di (phenanthroline) derivative represented by:   An electron transport material comprising the di (phenanthroline) derivative according to claim 1.   An organic electroluminescence device comprising the di (phenanthroline) derivative according to claim 1.

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