JP2015159238A - Compound for organic electroluminescent element and organic electroluminescent element using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compound for an organic electroluminescent element with a long life, and an organic electroluminescent element using the same.SOLUTION: The compound for an organic electroluminescent element is represented by general formula (I). (In the general formula (I), CZ represents a substituted or unsubstituted carbazoyl group; X represents a substituted or unsubstituted aryl group; Aand Aeach independently represent a substituted or unsubstituted anthracene; and Land Lare linking groups and each independently represent a substituted or unsubstituted arylene group.)

Description

  The present invention relates to a compound for an organic electroluminescence device and an organic electroluminescence device using the same.

  Organic electroluminescence devices have features such as self-luminance and high-speed response, and are expected to be applied to flat panel displays. In particular, since a two-layered type (laminated type) in which a hole-transporting organic thin film (hole-transporting layer) and an electron-transporting organic thin film (electron-transporting layer) are reported has been reported, a low voltage of 10 V or less. It has attracted attention as a large-area light-emitting element that emits light with voltage. A laminated organic electroluminescent element is composed of a thin film laminated film having a basic structure of positive electrode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / negative electrode. Among these, the light emitting layer may have the function of the hole transport layer and the electron transport layer as in the case of the two-layer type. Further, since various colors can be emitted by selecting the type of the fluorescent organic compound, application to various light emitting elements, display elements and the like is expected.

  In such an organic electroluminescence device, materials having various structures for various colors have been proposed in order to realize a long-life and high-efficiency device. Among them, the anthracene structure is used as a material having high stability. Among them, the anthracene dimer disclosed in Patent Document 1 is a material having a high glass transition temperature (Tg). By using this, a stable thin film can be produced, and a long-life organic electroluminescence device can be produced.

  Patent Document 2 discloses that a light-emitting layer is not formed of a single host material, but is mixed with a triarylamine compound that is a hole-transporting material, so that a longer-life organic electroluminescence device is used. It is disclosed that it is possible to produce.

  In addition, the anthracene derivative having one diphenylanthracene structure and one carbazoyl group simultaneously disclosed in Patent Document 3 has improved thermal stability due to the effect of the carbazoyl group. An electroluminescent element can be manufactured.

  However, even if these methods are used, the lifetime of the organic electroluminescent device is still insufficient, and materials and device configurations for further extending the lifetime are desired.

Japanese Patent No. 4190542 JP 2001-52870 A JP 2007-39431 A

  Therefore, the present invention examined the skeleton of the host material having anthracene as the mother skeleton from the viewpoint of the stability of the thin film in the organic electroluminescence device, and used a compound for an organic electroluminescence device having a longer life and the same. An object is to provide an organic electroluminescent device.

  In the present invention, as a result of examining various material skeletons in order to achieve the above object, it was found that the object can be achieved by a compound in which a carbazole group is arranged at the end of an anthracene dimer.

（一般式（Ｉ）において、ＣＺは置換または無置換のカルバゾイル基を、Ｘは置換または無置換のアリール基を、Ａ_１、Ａ_２は、それぞれ独立に置換または無置換のアントラセンを表す。Ｌ_１、Ｌ_２は連結基であり、それぞれ独立に置換または無置換のアリーレン基を表す。） That is, this invention is a compound for organic electroluminescent elements represented by the following general formula (I).

(In general formula (I), CZ represents a substituted or unsubstituted carbazoyl group, X represents a substituted or unsubstituted aryl group, and A ₁ and A ₂ each independently represents a substituted or unsubstituted anthracene. L ₁ and L ₂ each represent a linking group and each independently represents a substituted or unsubstituted arylene group.

According to another aspect of the present invention, there is provided an organic electric field light emitting device comprising a compound of the general formula (I) in an organic electroluminescent device in which at least one organic layer is sandwiched between a pair of electrodes composed of an anode and a cathode. It is a light emitting element. A long-life organic electroluminescent device can be provided by using a compound of general formula (I) having high thin film stability in an organic electroluminescent device comprising at least one organic layer.

  The present invention also provides an organic electroluminescent device in which at least one organic layer is sandwiched between a pair of electrodes consisting of an anode and a cathode, wherein the light emitting layer comprises a compound of the general formula (I) and a triarylamine derivative. It is an organic electroluminescent element characterized by comprising a mixed layer. In the general formula (I), CZ represents a carbazoyl group, and the carbazoyl group is arranged at the end of the molecule, so that polarity is generated in the whole molecule. In the mixed film with the polar compound, the compatibility is improved, a stable thin film can be produced, and a long-life organic electroluminescence device can be provided.

  The present invention also relates to an organic electroluminescent device in which at least one organic layer is sandwiched between a pair of electrodes consisting of an anode and a cathode, wherein the hole injection layer comprises the compound of the general formula (I) and the electron acceptor. An organic electroluminescent element comprising a mixed layer with a compound. By reducing the work function of the compound of general formula (I) using an electron acceptor compound, the compound of general formula (I) can be used as a hole injection layer. In particular, since the compound of the general formula (I) has polarity, it has good adhesion to the anode, so that a stable thin film can be produced and a long-life organic electroluminescence device can be provided.

  According to the present invention, the skeleton of the host material having anthracene as the host skeleton is studied from the viewpoint of the stability of the thin film in the organic electroluminescence device, and the compound for the organic electroluminescence device having a longer life and the use thereof are used. It was possible to provide an organic electroluminescent device.

1 is an outline of an organic electroluminescence device of the present invention. 1H NMR spectrum of H1. IR spectrum of H1. 1H NMR spectrum of H2. IR spectrum of H2.

（一般式（Ｉ）において、ＣＺは置換または無置換のカルバゾイル基を、Ｘは置換または無置換のアリール基を、Ａ_１、Ａ_２は、それぞれ独立に置換または無置換のアントラセンを表す。Ｌ_１、Ｌ_２は連結基であり、それぞれ独立に置換または無置換のアリーレン基を表す。） This embodiment is a compound for organic electroluminescent elements represented by the following general formula (I).

(In general formula (I), CZ represents a substituted or unsubstituted carbazoyl group, X represents a substituted or unsubstituted aryl group, and A ₁ and A ₂ each independently represents a substituted or unsubstituted anthracene. L ₁ and L ₂ each represent a linking group and each independently represents a substituted or unsubstituted arylene group.

  Symmetrical molecular structures are easily aligned and crystallized during high-temperature storage and high-temperature driving, but the aromatic compound represented by the general formula (I) can be prevented from being crystallized due to its asymmetric molecular structure. Therefore, it is considered that the stability as a thin film is increased. Furthermore, since the carbazoyl group is arranged at the end of the molecule, polarity is generated in the whole molecule, and it is considered that the stability as a thin film is increased by this polarity. In particular, the presence of two anthracene groups in the molecule makes it possible to increase the polarity as compared with the case of one and improve the thermal stability by increasing the molecular weight. Moreover, it is considered that the compatibility is improved in a mixed film with a polar compound such as a triarylamine derivative due to the polarity, and the effect is remarkable. It is thought that the lifetime as an organic electroluminescent element is extended as a result by the increase in stability of such a thin film.

  There are many substituents that impart polarity other than the carbazoyl group, and examples thereof include nitrogen-containing heterocyclic compounds such as pyridyl groups and amine compounds such as diphenylamino groups. However, when such a compound is used, the electron accepting property or electron donating property of the whole molecule becomes strong, and the bipolar property required for the host material is lowered. Besides, it is possible to generate the polarity only with the hydrocarbon material, but the polarity in this case is very small and cannot contribute to the improvement of the thin film stability. On the other hand, the carbazoyl group also has a nitrogen atom, and the polarity derived from the nitrogen atom is generated, but the electron donating property is kept low due to the influence of the five-membered ring structure. For this reason, only the polarity of the molecule can be increased without changing the value of the energy level (HOMO, LUMO, Eg, etc.) optimum for the host material possessed by anthracene.

Coupling position to L ₁ of the carbazoyl group 3-position, 6-position, preferably any of the 9-position. This substitution position is easy to synthesize. The carbazoyl group is preferably unsubstituted, but may be substituted, and usually a low molecular weight aryl group such as a phenyl group or a biphenyl group is preferred. The substitution positions are preferably the 3rd, 6th and 9th positions as in the linking position.

In the general formula (I), A ₁ and A ₂ represent anthracene. A ₁ is connected to the linking groups L ₁ and L ₂ and A ₂ is connected to L _{2 and the} substituent X at two positions, and preferable connecting positions are 2-position, 3-position, 6-position, 7-position, 9-position of anthracene. However, the 9th and 10th positions are more preferable because they are easily synthesized. A ₁ and A ₂ may each be substituted, and usually a low molecular weight aryl group such as a phenyl group or a biphenyl group is preferred. The substitution position is preferably the 2-position, 3-position, 6-position, 7-position, 9-position, and 10-position similarly to the linking position.

  X is a substituted or unsubstituted aryl group, and a low molecular weight aryl group such as a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group is preferable because it can be easily synthesized. These substituents may be further substituted, but aryl groups having no polarity are preferred.

L ₁ and L ₂ are linking groups, each of which is a substituted or unsubstituted arylene group. A low molecular weight arylene group such as a phenylene group, a biphenylene group, or a naphthylene group is preferred because it can be easily synthesized. These linking groups are usually preferably unsubstituted, but may be further substituted, in which case an aryl group having no polarity is preferred.

  The molecular weight of the compound is not particularly limited, but is preferably 1000 or less in consideration of the film forming process. When the molecular weight exceeds 1000, synthesis becomes difficult due to a decrease in solubility, and the coating process for application to a device becomes difficult. In addition, even when a device is produced by a vapor deposition process, the vapor deposition temperature is often a high temperature of 400 ° C. or more, and the material may be decomposed.

  Although the specific example of the compound of this embodiment represented by general formula (I) below is shown, this embodiment is not limited to these.

  Moreover, this invention is an organic electroluminescent element characterized by including the compound of the said general formula (I). An organic electroluminescent device according to an embodiment of the present invention will be described with reference to FIG. As shown in FIG. 1, the organic electroluminescent device 1 includes an anode 3, a hole injection layer 4, a hole transport layer 5, a light emitting layer 6, an electron transport layer 7, an electron injection layer 8, and a cathode 9 on a substrate 2. In order.

  The substrate 2 is preferably formed of a transparent or translucent material, such as a glass plate, a transparent plastic sheet, a translucent plastic sheet, quartz, transparent ceramics, or a composite sheet combining these. The substrate 2 may be formed from an opaque material. In this case, the organic electroluminescent element 1 should just reverse the lamination | stacking order shown by FIG. Furthermore, the emission color may be controlled by combining the substrate 2 with, for example, a color filter film, a color conversion film, a dielectric reflection film, or the like.

  The anode 3 preferably uses a metal, an alloy or an electrically conductive compound having a relatively large work function as an electrode material. Examples of the electrode material used for the anode 3 include gold, platinum, silver, copper, cobalt, nickel, palladium, vanadium, tungsten, tin oxide, zinc oxide, ITO (Indium Tin Oxide), polythiophene, and polypyrrole. These electrode materials may be used alone or in combination. The anode 3 can form these electrode materials on the substrate 2 by, for example, a vapor phase growth method such as a vapor deposition method or a sputtering method. Further, the anode 3 may have a single layer structure or a multilayer structure.

  The hole injection layer 4 is a layer containing a compound having a function of facilitating injection of holes from the anode 3. In addition, adhesion with the anode 3 is also an important factor when selecting a material. Specifically, it can be formed using at least one phthalocyanine derivative, triarylmethane derivative, triarylamine derivative, or the like. Since the compound represented by the general formula (I) of the present invention has a work function larger than that of the anode 3, the compound is usually not suitable for the hole injection layer 4. However, when holes are forcibly generated using an electron acceptor such as antimony chloride, iron chloride, or molybdenum oxide, hole injection from the anode 3 is facilitated, so that the general formula (I ) Can also be used as the hole injection layer 4. In particular, since the compound of the present invention has a polarity mainly based on a carbazoyl group, it has good adhesion to the anode, can be used suitably, and can provide a long-life organic electroluminescence device.

  The hole transport layer 5 is a layer containing a compound having a function of transporting injected holes to the light emitting layer 6 and a function of preventing electrons in the light emitting layer from being injected into the hole transport layer 5. is there. The hole transport layer 5 includes at least one hydrocarbon compound such as a triarylmethane derivative, a triarylamine derivative, a stilbene derivative, a polysilane derivative, polyphenylene vinylene and a derivative thereof, polythiophene and a derivative thereof, a carbazole derivative, or an anthracene derivative. Can be formed. Moreover, the compound represented by the general formula (I) of the present invention can also be used as the hole transport layer 5, and a long-life organic electroluminescence device can be provided.

  In addition, if it is a material which has the function of the positive hole injection layer 4 and the positive hole transport layer 5, as a positive hole injection transport layer, it can fulfill the function for two layers by a single layer. On the other hand, the hole injection layer 4 and the hole transport layer 5 can be further functionally separated into a plurality of layers.

  The light emitting layer 6 is a layer containing a compound having a function of transporting injected holes and electrons and a function of generating excitons by recombination of holes and electrons. Hydrocarbon compounds such as naphthalene derivatives, anthracene derivatives, phenanthrene derivatives, pyrene derivatives, fluoranthene derivatives, and naphthacene derivatives are preferably used. The compound represented by the general formula (I) in the present invention is preferably used for the light emitting layer 6 and is usually used as a host material, and can provide a long-life organic electroluminescence device.

  In addition to the host material, the light emitting layer 6 may contain another fluorescent substance as a light emitting doping material. Examples of fluorescent substances include compounds such as quinacridone, rubrene, and styryl dyes, quinoline derivatives such as metal complex dyes having 8-quinolinol or a derivative thereof such as tris (8-quinolinolato) aluminum as a ligand, tetraphenyl, and the like. Examples thereof include butadiene, anthracene, fluoranthene, pyrene, perylene, coronene, 12-phthaloperinone derivatives, phenylanthracene derivatives, tetraarylethene derivatives, aromatic amine derivatives, and the like. In particular, aromatic amine derivatives such as aminonaphthalene derivatives, aminopyrene derivatives, aminophenanthrene derivatives, aminofluorene derivatives, aminochrysene derivatives, aminoanthracene derivatives, and aminoperylene derivatives are very preferable materials.

  The light emitting layer 6 may contain other compounds in addition to the host material and the light emitting doping material. It can be used by adjusting the transport of carriers by mixing other compounds, or by changing the emission color by mixing fluorescent dyes. Examples of compounds that regulate carrier transport include electron transport such as 8-quinolinol such as tris (8-quinolinolato) aluminum or its derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, imidazopyridine derivatives, imidazopyrimidine derivatives, phenanthroline derivatives, and the like. Or a hole transporting compound such as a triarylamine derivative can be preferably used. Since the compound represented by the general formula (I) in the present invention has a polarity based on a carbazoyl group, the compatibility with a highly polar material such as an electron transporting compound or a hole transporting compound is also good. A stable thin film can be formed over a long period of time.

  The electron transport layer 7 has a function of transporting injected electrons and a function of preventing holes from being injected from the light emitting layer 6. The electron transport layer 7 is composed of an organometallic complex having an 8-quinolinol-like derivative such as tris (8-quinolinolato) aluminum as a ligand, an oxadiazole derivative, a triazole derivative, a triazine derivative, a quinoline derivative, a quinoxaline derivative, diphenyl At least one quinone derivative, nitro-substituted fluorenone derivative, thiopyrandioxide derivative, pyridine derivative, pyrimidine derivative, imidazopyridine derivative, imidazopyrimidine derivative, heterocyclic compound such as phenanthroline derivative, hydrocarbon derivative such as anthracene derivative or fluoranthene derivative, etc. It can be formed using seeds. In addition, the compound represented by the general formula (I) of the present invention can also be used as an electron transporting layer. In particular, when the compound represented by the general formula (I) is used in the light emitting layer, the same material is converted into an electron. It is preferable to use it for the transport layer.

  The electron injection layer 8 has a function of facilitating injection of electrons from the cathode 9 and a function of improving adhesion with the cathode 9. The electron injection layer 8 is composed of an organometallic complex having an 8-quinolinol or its derivative such as tris (8-quinolinolato) aluminum as a ligand, oxadiazole derivative, triazole derivative, triazine derivative, quinoline derivative, quinoxaline derivative, diphenyl A quinone derivative, a nitro-substituted fluorenone derivative, a thiopyrandioxide derivative, a pyridine derivative, a pyrimidine derivative, an imidazopyridine derivative, an imidazopyrimidine derivative, a phenanthroline derivative, or the like can be used. The compound represented by the general formula (I) of the present invention is usually not suitable for the electron injection layer 8, but when a cathode 9 having excellent injectability is used, or relatively, such as alkali metal or alkaline earth metal. The electron injection layer 8 can be used by doping a metal having a low work function and a salt thereof.

  For the cathode 9, a metal having a relatively small work function and a salt thereof, an alloy, or an electrically conductive compound can be used as an electrode constituent material. For example, lithium, sodium, calcium, magnesium, indium, ruthenium, titanium, manganese, yttrium, aluminum as metal, lithium oxide, sodium oxide, calcium oxide, magnesium oxide as oxide, lithium fluoride, fluoride as fluoride Sodium, calcium fluoride, magnesium fluoride, alloys include lithium-indium alloy, sodium-potassium alloy, magnesium-silver alloy, magnesium-indium alloy, aluminum-lithium alloy, aluminum-calcium alloy, aluminum-magnesium alloy, electrical conduction Examples of the functional compound include a graphite thin film.

  These electrode constituent materials may be used alone or in combination. The cathode 9 can be formed of these electrode materials on the electron injection layer 8 by a method such as vapor deposition, sputtering, ionized vapor deposition, ion plating, or cluster ion beam. Further, the cathode 9 may have a single layer structure or a multilayer structure. In order to efficiently extract light emitted from the organic electroluminescent device, at least one of the anode 3 and the cathode 9 is preferably transparent or translucent, and generally has a light transmittance of 80% or more. More preferably, the material and thickness of the anode 3 or the cathode 9 are set.

The organic electroluminescent element is often formed by a vapor deposition process, but the compound represented by the general formula (I) in the present invention has high solubility due to low symmetry, and can be sufficiently applied by the coating process. Film formation is possible. Therefore, the cost of the process can be reduced by using the compound of the present invention. As the coating solvent, a hydrocarbon solvent such as toluene or xylene, or a halogen solvent such as dichloroethane can be used. As a film forming method, a spin coating method, various printing methods such as gravure printing, an ink jet method, or the like can be used. In the case of the spin coating method, a thin film of about 50 nm to 200 nm can be formed by using a solution having a concentration of about 1 to 3%.

  Hereinafter, specific synthesis examples of the compound of the present invention will be shown to explain the present invention in more detail.

１２．７ｇ（５０ｍｍｏｌ）の９−フェニルアントラセンをＮ，Ｎ−ジメチルホルムアミド２５０ｍｌに溶解し、９．８ｇ（５５ｍｍｏｌ）のＮ−ブロモコハク酸イミドを加えて、室温で１２時間反応させた。蒸留水を加えた後に析出した固体をろ過し、カラムクロマトグラフィーを用いて精製を行い、１３．６ｇ（４０．８ｍｍｏｌ）の９−ブロモ−１０−フェニルアントラセンを得た。収率は８１．６％であった。

12.7 g (50 mmol) of 9-phenylanthracene was dissolved in 250 ml of N, N-dimethylformamide, 9.8 g (55 mmol) of N-bromosuccinimide was added, and the mixture was reacted at room temperature for 12 hours. The solid precipitated after adding distilled water was filtered and purified using column chromatography to obtain 13.6 g (40.8 mmol) of 9-bromo-10-phenylanthracene. The yield was 81.6%.

１３．６ｇ（４０．８ｍｍｏｌ）の９−ブロモ−１０−フェニルアントラセンを脱水テトラヒドロフランに溶解し、−７０℃に冷却した。ここに２８．３ｍｌ（４５ｍｍｏｌ）のｎブチルリチウムのｎヘキサン溶液を滴下し、更に１時間後に１１．７ｇ（８０ｍｍｏｌ）のホウ酸トリエチルを加えた。４時間反応を行った後に希塩酸溶液を加えた。次いで分離した有機層を用いて再結晶を行い、８．９ｇ（２９．９ｍｍｏｌ）の１０−フェニルアントラセン−９−ボロン酸を得た。収率は７３．３％であった。

13.6 g (40.8 mmol) of 9-bromo-10-phenylanthracene was dissolved in dehydrated tetrahydrofuran and cooled to -70 ° C. 28.3 ml (45 mmol) of n-butyllithium in n-hexane was added dropwise thereto, and 11.7 g (80 mmol) of triethyl borate was further added after 1 hour. After reacting for 4 hours, a diluted hydrochloric acid solution was added. The separated organic layer was then recrystallized to obtain 8.9 g (29.9 mmol) of 10-phenylanthracene-9-boronic acid. The yield was 73.3%.

２．９８１５ｇ（１０．０ｍｍｏｌ）の１０−フェニルアントラセン−９−ボロン酸と１８．８７３ｇ（８０．０ｍｍｏｌ）の１，４−ジブロモベンゼン、触媒としてのテトラキストリフェニルホスフィンパラジウム６９３ｍｇをトルエン８０ｍｌ、エタノール２０ｍｌの混合溶媒に溶解した。ここに２Ｍの炭酸ナトリウム水溶液３０ｍｌを加え３０℃にて７２時間反応した。反応終了後に有機層を分離し、カラムクロマトグラフィーによる精製を行い、２．３１ｇ（５．１ｍｍｏｌ）の９−（４−ブロモフェニル）−１０−フェニルアントラセンを得た。収率は５１．４％であった。

2.9815 g (10.0 mmol) 10-phenylanthracene-9-boronic acid, 18.873 g (80.0 mmol) 1,4-dibromobenzene, tetrakistriphenylphosphine palladium 693 mg as a catalyst in 80 ml toluene, 20 ml ethanol In a mixed solvent. 30 ml of 2M sodium carbonate aqueous solution was added thereto and reacted at 30 ° C. for 72 hours. After completion of the reaction, the organic layer was separated and purified by column chromatography to obtain 2.31 g (5.1 mmol) of 9- (4-bromophenyl) -10-phenylanthracene. The yield was 51.4%.

２．０４５ｇ（５．０ｍｍｏｌ）の９−（４−ブロモフェニル）−１０−フェニルアントラセンと１．３３２ｇ（６．０ｍｍｏｌ）のアントラセン−９−ボロン酸、触媒としてのテトラキストリフェニルホスフィンパラジウム１７３ｍｇをトルエン２５ｍｌ、エタノール５ｍｌの混合溶媒に溶解した。ここに２Ｍの炭酸ナトリウム水溶液７．５ｍｌを加え１１０℃にて１７時間反応した。反応終了後に有機層を分離し、カラムクロマトグラフィーによる精製を行い、２．３２ｇ（４．６ｍｍｏｌ）の９−（４−（アントラセン―１０−イル）フェニル）−１０−フェニルアントラセンを得た。収率は５１．４％であった。

2.045 g (5.0 mmol) of 9- (4-bromophenyl) -10-phenylanthracene and 1.332 g (6.0 mmol) of anthracene-9-boronic acid, 173 mg of tetrakistriphenylphosphine palladium as a catalyst in toluene It was dissolved in a mixed solvent of 25 ml and ethanol 5 ml. 7.5M of 2M sodium carbonate aqueous solution was added here, and it reacted at 110 degreeC for 17 hours. After completion of the reaction, the organic layer was separated and purified by column chromatography to obtain 2.32 g (4.6 mmol) of 9- (4- (anthracen-10-yl) phenyl) -10-phenylanthracene. The yield was 51.4%.

２．３１４ｇ（４．６ｍｍｏｌ）の９−（４−（アントラセン―１０−イル）フェニル）−１０−フェニルアントラセンをＮ，Ｎ−ジメチルホルムアミド１２０ｍｌに溶解し、０．８９０ｇ（５．１ｍｍｏｌ）のＮ−ブロモコハク酸イミドを加えて、室温で５時間反応させた。蒸留水を加えた後に析出した固体をろ過し、カラムクロマトグラフィーを用いて精製を行い、２．５３２ｇ（４０．８ｍｍｏｌ）の９−（４−（９−ブロモアントラセン―１０−イル）フェニル）−１０−フェニルアントラセンを得た。収率は９４．６％であった。

2.314 g (4.6 mmol) 9- (4- (anthracen-10-yl) phenyl) -10-phenylanthracene was dissolved in 120 ml N, N-dimethylformamide and 0.890 g (5.1 mmol) N -Bromosuccinimide was added and allowed to react at room temperature for 5 hours. The solid precipitated after adding distilled water was filtered and purified using column chromatography to obtain 2.532 g (40.8 mmol) of 9- (4- (9-bromoanthracen-10-yl) phenyl)- 10-phenylanthracene was obtained. The yield was 94.6%.

（合成例１）・・・例示化合物Ｈ１の合成
１．１７ｇ（２．０ｍｍｏｌ）の９−（４−（９−ブロモアントラセン―１０−イル）フェニル）−１０−フェニルアントラセンと０．６３ｇ（２．２ｍｍｏｌ）の４−（９Ｈ−カルバザイル）フェニルボロン酸、触媒としてのテトラキストリフェニルホスフィンパラジウム１１５ｍｇをトルエン４０ｍｌ、エタノール１０ｍｌの混合溶媒に溶解した。ここに２Ｍの炭酸ナトリウム水溶液１０ｍｌを加え１２０℃にて１８時間反応した。反応終了後に有機層を分離し、カラムクロマトグラフィーによる精製を行い、１．２０ｇ（１６．６ｍｍｏｌ）の例示化合物Ｈ１を得た。収率は８０．３％であった。得られた固体の１Ｈ ＮＭＲとＩＲを測定し、この固体が目的物である例示化合物Ｈ１であることを確認した。図２および図３に測定データを示した。

Synthesis Example 1 Synthesis of Exemplified Compound H1 1.17 g (2.0 mmol) of 9- (4- (9-bromoanthracen-10-yl) phenyl) -10-phenylanthracene and 0.63 g (2 .2 mmol) of 4- (9H-carbazayl) phenylboronic acid and 115 mg of tetrakistriphenylphosphine palladium as a catalyst were dissolved in a mixed solvent of 40 ml of toluene and 10 ml of ethanol. 10 ml of 2M sodium carbonate aqueous solution was added thereto and reacted at 120 ° C. for 18 hours. After completion of the reaction, the organic layer was separated and purified by column chromatography to obtain 1.20 g (16.6 mmol) of exemplified compound H1. The yield was 80.3%. 1H NMR and IR of the obtained solid were measured, and it was confirmed that this solid was Exemplified Compound H1 which was the target product. The measurement data are shown in FIGS.

４．４７２ｇ（１５．０ｍｍｏｌ）の１０−フェニルアントラセン−９−ボロン酸と１８．８７３ｇ（７５．０ｍｍｏｌ）の１，３−ジブロモベンゼン、触媒としてのテトラキストリフェニルホスフィンパラジウム８６７ｍｇをトルエン１５０ｍｌ、エタノール５０ｍｌの混合溶媒に溶解した。ここに２Ｍの炭酸ナトリウム水溶液７５ｍｌを加え１００℃にて５時間反応した。反応終了後に有機層を分離し、カラムクロマトグラフィーによる精製を行い、４．３１７ｇ（１０．５ｍｍｏｌ）の９−（３−ブロモフェニル）−１０−フェニルアントラセンを得た。収率は７０．３％であった。

4.472 g (15.0 mmol) of 10-phenylanthracene-9-boronic acid, 18.873 g (75.0 mmol) of 1,3-dibromobenzene, 867 mg of tetrakistriphenylphosphine palladium as a catalyst, 150 ml of toluene and 50 ml of ethanol In a mixed solvent. To this, 75 ml of 2M aqueous sodium carbonate solution was added and reacted at 100 ° C. for 5 hours. After completion of the reaction, the organic layer was separated and purified by column chromatography to obtain 4.317 g (10.5 mmol) of 9- (3-bromophenyl) -10-phenylanthracene. The yield was 70.3%.

２．０４５ｇ（５．０ｍｍｏｌ）の９−（３−ブロモフェニル）−１０−フェニルアントラセンと１．３３２ｇ（６．０ｍｍｏｌ）のアントラセン−９−ボロン酸、触媒としてのテトラキストリフェニルホスフィンパラジウム１７３ｍｇをトルエン２５ｍｌ、エタノール５ｍｌの混合溶媒に溶解した。ここに２Ｍの炭酸ナトリウム水溶液７．５ｍｌを加え１１０℃にて２４時間反応した。反応終了後に有機層を分離し、カラムクロマトグラフィーによる精製を行い、２．４２ｇ（４．８ｍｍｏｌ）の９−（３−（アントラセン―１０−イル）フェニル）−１０−フェニルアントラセンを得た。収率は９５．３％であった。

2.045 g (5.0 mmol) of 9- (3-bromophenyl) -10-phenylanthracene, 1.332 g (6.0 mmol) of anthracene-9-boronic acid, 173 mg of tetrakistriphenylphosphine palladium as a catalyst in toluene It was dissolved in a mixed solvent of 25 ml and ethanol 5 ml. 7.5 ml of 2M sodium carbonate aqueous solution was added thereto and reacted at 110 ° C. for 24 hours. After completion of the reaction, the organic layer was separated and purified by column chromatography to obtain 2.42 g (4.8 mmol) of 9- (3- (anthracen-10-yl) phenyl) -10-phenylanthracene. The yield was 95.3%.

２．４１５ｇ（４．８ｍｍｏｌ）の９−（３−（アントラセン―１０−イル）フェニル）−１０−フェニルアントラセンをＮ，Ｎ−ジメチルホルムアミド１３０ｍｌに溶解し、０．９３４ｇ（５．３ｍｍｏｌ）のＮ−ブロモコハク酸イミドを加えて、６０℃にて７２時間反応させた。蒸留水を加えた後に析出した固体をろ過し、カラムクロマトグラフィーを用いて精製を行い、２．２４７ｇ（４０．８ｍｍｏｌ）の９−（３−（９−ブロモアントラセン―１０−イル）フェニル）−１０−フェニルアントラセンを得た。収率は８０．４％であった。

2.415 g (4.8 mmol) 9- (3- (anthracen-10-yl) phenyl) -10-phenylanthracene was dissolved in 130 ml N, N-dimethylformamide and 0.934 g (5.3 mmol) N -Bromosuccinimide was added and reacted at 60 ° C for 72 hours. The solid precipitated after adding distilled water was filtered and purified using column chromatography to obtain 2.247 g (40.8 mmol) of 9- (3- (9-bromoanthracen-10-yl) phenyl)- 10-phenylanthracene was obtained. The yield was 80.4%.

２．２５ｇ（３．８ｍｍｏｌ）の９−（３−（９−ブロモアントラセン―１０−イル）フェニル）−１０−フェニルアントラセンと１．１０ｇ（３．８ｍｍｏｌ）の４−（９Ｈ−カルバザイル）フェニルボロン酸、触媒としてのテトラキストリフェニルホスフィンパラジウム１１５ｍｇをトルエン８０ｍｌ、エタノール２０ｍｌの混合溶媒に溶解した。ここに２Ｍの炭酸ナトリウム水溶液２０ｍｌを加え１１０℃にて１８時間反応した。反応終了後に有機層を分離し、カラムクロマトグラフィーによる精製を行い、１．７６ｇ（２．３６ｍｍｏｌ）の例示化合物Ｈ２を得た。収率は６１．４％であった。得られた固体の１Ｈ ＮＭＲとＩＲを測定し、この固体が目的物である例示化合物Ｈ２であることを確認した。図４および図５に測定データを示した。

(Synthesis Example 2) ... Synthesis of Exemplified Compound H2

2.25 g (3.8 mmol) 9- (3- (9-bromoanthracen-10-yl) phenyl) -10-phenylanthracene and 1.10 g (3.8 mmol) 4- (9H-carbazayl) phenylboron 115 mg of tetrakistriphenylphosphine palladium as an acid and a catalyst was dissolved in a mixed solvent of 80 ml of toluene and 20 ml of ethanol. 20 ml of 2M sodium carbonate aqueous solution was added thereto and reacted at 110 ° C. for 18 hours. After completion of the reaction, the organic layer was separated and purified by column chromatography to obtain 1.76 g (2.36 mmol) of exemplified compound H2. The yield was 61.4%. 1H NMR and IR of the obtained solid were measured, and it was confirmed that this solid was Exemplified Compound H2 which was the target product. The measured data are shown in FIGS.

  Hereinafter, specific examples of the present invention will be shown together with comparative examples, and the present invention will be described in more detail.

Example 1
An ITO transparent electrode thin film having a thickness of 100 nm was formed on a glass substrate by RF sputtering and patterned. This glass substrate with an ITO transparent electrode was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol, and then pulled up from boiling ethanol and dried. After the surface of the transparent electrode was washed with UV / O _3, it was fixed to a substrate holder of a vacuum deposition apparatus, and the inside of the tank was depressurized to 1 × 10 ⁻⁴ Pa or less.

  Next, while maintaining the reduced pressure state, Chemical Formula 13 having the following structure was deposited at a deposition rate of 0.1 nm / sec to a film thickness of 50 nm to form a hole injection layer.

  Next, chemical compound 14 having the following structure was deposited at a deposition rate of 0.1 nm / sec to a thickness of 10 nm to form a hole transport layer.

  Furthermore, while maintaining the reduced pressure state, the compound H1 of the present invention as a host material and the chemical structure 15 of the following structure as a light-emitting dopant with a volume ratio of 97: 3 and a total deposition rate of 0.1 nm / sec and a thickness of 40 nm The light emitting layer was formed by vapor deposition.

  Next, while maintaining the reduced pressure state, the compound H1 of the present invention was deposited at 10 nm, followed by tris (8-hydroxyquinoline) aluminum (Alq3) at 5 nm and a deposition rate of 0.1 nm / sec to form an electron transport layer. .

  Next, LiF was deposited at a deposition rate of 0.1 nm / sec to a thickness of 0.5 nm to form an electron injection electrode, Al was deposited as a protective electrode to 100 nm, and finally glass sealed to obtain an organic electroluminescent device. .

When a direct current voltage was applied to the organic electroluminescent element, blue light emission derived from a light emitting dopant having an initial luminance of 440 cd / m ² and a luminance half life of 2600 hours was obtained at a current density of 10 mA / cm ² .

(Examples 2-23, Comparative Examples 1-2)
An organic electroluminescent element was produced in the same manner as in Example 1 except that the compounds listed in Table 1 were used instead of the compound (H1). Table 1 shows the test results of the initial luminance and the luminance half time of these elements. The compound shown in the comparative example has the following structure.

(Example 24)
An ITO transparent electrode thin film having a thickness of 100 nm was formed on a glass substrate by RF sputtering and patterned. This glass substrate with an ITO transparent electrode was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol, and then pulled up from boiling ethanol and dried. After the surface of the transparent electrode was washed with UV / O _3, it was fixed to a substrate holder of a vacuum deposition apparatus, and the inside of the tank was depressurized to 1 × 10 ⁻⁴ Pa or less.

Next, while maintaining the reduced pressure state, Chemical Formula 13 was deposited at a deposition rate of 0.1 nm / sec to a film thickness of 50 nm to form a hole injection layer.

  Next, Chemical Formula 14 was deposited at a deposition rate of 0.1 nm / sec to a thickness of 10 nm to form a hole transport layer.

  Further, while maintaining the reduced pressure state, the compound H1 of the present invention, the chemical compound 14 and the chemical compound 15 as the host material were made into a thickness of 40 nm at a volume ratio of 87: 10: 3 and an overall deposition rate of 0.1 nm / sec. It vapor-deposited and it was set as the light emitting layer.

  Next, while maintaining the reduced pressure state, the compound H1 of the present invention was deposited at 10 nm, followed by tris (8-hydroxyquinoline) aluminum (Alq3) at 5 nm and a deposition rate of 0.1 nm / sec to form an electron transport layer. .

  Next, LiF was deposited at a deposition rate of 0.1 nm / sec to a thickness of 0.5 nm to form an electron injection electrode, Al was deposited as a protective electrode to 100 nm, and finally glass sealed to obtain an organic electroluminescent device. .

When a DC voltage was applied to the organic electroluminescence device, blue light emission derived from a light emitting dopant having an initial luminance of 570 cd / m ² and a luminance half life of 3070 hours at a current density of 10 mA / cm ² was obtained.

(Examples 25-39, Comparative Examples 3-4)
An organic electroluminescent element was produced in the same manner as in Example 23 except that the compounds listed in Table 1 were used instead of the compound (H1). Table 2 shows the test results of the initial luminance and luminance half time of these elements.

(Example 40)
An ITO transparent electrode thin film having a thickness of 100 nm was formed on a glass substrate by RF sputtering and patterned. This glass substrate with an ITO transparent electrode was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol, and then pulled up from boiling ethanol and dried. After the surface of the transparent electrode was washed with UV / O _3, it was fixed to a substrate holder of a vacuum deposition apparatus, and the inside of the tank was depressurized to 1 × 10 ⁻⁴ Pa or less.

  Next, while maintaining the reduced pressure state, the compound H1 of the present invention and molybdenum oxide were deposited at a volume ratio of 95: 5 to a film thickness of 50 nm at an overall deposition rate of 0.1 nm / sec. did.

  Next, the compound H1 of the present invention was deposited to a thickness of 10 nm at a deposition rate of 0.1 nm / sec to form a hole transport layer.

  Further, while maintaining the reduced pressure state, the compound H1 of the present invention as a host material and Chemical Formula 15 were vapor-deposited at a volume ratio of 97: 3 to a thickness of 40 nm at an overall vapor deposition rate of 0.1 nm / sec. did.

  Next, while maintaining the reduced pressure state, the compound H1 of the present invention was deposited at 10 nm, followed by tris (8-hydroxyquinoline) aluminum (Alq3) at 5 nm and a deposition rate of 0.1 nm / sec to form an electron transport layer. .

  Next, LiF was deposited at a deposition rate of 0.1 nm / sec to a thickness of 0.5 nm to form an electron injection electrode, Al was deposited as a protective electrode to 100 nm, and finally glass sealed to obtain an organic electroluminescent device. .

When a DC voltage was applied to the organic electroluminescence device, blue light emission derived from a light emitting dopant having an initial luminance of 410 cd / m ² and a luminance half life of 3740 hours was obtained at a current density of 10 mA / cm ² .

(Examples 41-55, Comparative Examples 5-6)
An organic electroluminescent element was produced in the same manner as in Example 40 except that the compounds listed in Table 1 were used instead of the compound (H1). Table 3 shows the test results of the initial luminance and the luminance half time of these elements.

  As described above, the compound in which the carbazoyl group is arranged at the end of the anthracene dimer according to the present invention is useful as a compound for a long-life organic electroluminescence device. An organic electroluminescent element utilizing this can be applied to a light emitting device such as a display or illumination.

DESCRIPTION OF SYMBOLS 1 Organic electroluminescent element 2 Substrate 3 Anode 4 Hole injection layer 5 Hole transport layer 6 Light emitting layer 7 Electron transport layer 8 Electron injection layer 9 Cathode

Claims (4)

The compound for organic electroluminescent elements represented by the following general formula (I).

(In general formula (I), CZ represents a substituted or unsubstituted carbazoyl group, X represents a substituted or unsubstituted aryl group, and A ₁ and A ₂ each independently represents a substituted or unsubstituted anthracene. L ₁ and L ₂ each represent a linking group and each independently represents a substituted or unsubstituted arylene group.   In the organic electroluminescent element in which at least one organic layer is sandwiched between a pair of electrodes composed of an anode and a cathode, at least one of the organic layers is a component of the compound according to claim 1 alone or as a component of a mixture. An organic electroluminescent device comprising:   In the organic electroluminescence device in which at least one organic layer is sandwiched between a pair of electrodes composed of an anode and a cathode, the light emitting layer is composed of a mixed layer of the compound according to claim 1 and a triarylamine derivative. An organic electroluminescent device characterized by that.   2. The organic electroluminescence device in which at least one organic layer is sandwiched between a pair of electrodes consisting of an anode and a cathode, wherein the hole injection layer is a mixed layer of the compound according to claim 1 and an electron acceptor compound. An organic electroluminescent device comprising:

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