JP2008285450A - Condensed ring aromatic compound and organic light-emitting element using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic light-emitting element having high-efficiency and high-luminance optical output and also high durability. <P>SOLUTION: The organic light-emitting element is constituted of an anode, a cathode and a layer comprising an organic compound nipped between the anode and the cathode, and the layer comprising the organic compound contains at least one kind of a condensed ring aromatic compound represented by general formula [I] (wherein, R<SB>1</SB>to R<SB>14</SB>are each a hydrogen atom, an alkyl group, a substituted or nonsubstituted aralkyl group, a substituted or nonsubstituted aryl group, a substituted or nonsubstituted heterocyclic group, a substituted amino group or a halogen atom). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a condensed ring aromatic compound and an organic light-emitting device using the same.

  An organic light-emitting element is an element in which a thin film containing a fluorescent organic compound or a phosphorescent organic compound is sandwiched between an anode and a cathode. In addition, by injecting electrons and holes from each electrode, excitons of a fluorescent compound or a phosphorescent compound are generated, and the organic light emitting element emits light when the excitons return to the ground state.

  In addition, recent advances in organic light-emitting elements are remarkable, and the characteristics are that high luminance, a variety of emission wavelengths, high-speed response, and light-emitting devices can be made thinner and lighter at a low applied voltage. This suggests that the organic light emitting device has a wide range of uses.

  However, under the present circumstances, light output with higher brightness or higher conversion efficiency is required. In addition, there are still many problems in terms of durability, such as changes over time due to long-term use and deterioration due to atmospheric gas containing oxygen or moisture. Furthermore, when considering application to a full-color display or the like, it is necessary to emit blue, green, and red with high color purity, but these problems have not been sufficiently solved.

  As one method for solving the above-described problems, it has been proposed to use a relatively large condensed ring aromatic compound containing a five-membered ring structure as a material for an organic light-emitting device. Examples of such condensed ring aromatic compounds and organic light-emitting devices using them include those disclosed in Patent Documents 1 to 4.

Japanese Patent Laid-Open No. 10-330295 JP 2002-170681 A JP 2002-110356 A Japanese Patent Laid-Open No. 11-176573

  An object of the present invention is to provide a novel fused ring aromatic compound. Another object of the present invention is to provide a durable organic light-emitting device having a light output with high efficiency and high brightness. Still another object of the present invention is to provide an organic light emitting device that is easy to manufacture and can be manufactured at a relatively low cost.

  The condensed ring aromatic compound of the present invention is represented by the following general formula [I].

（式［Ｉ］において、Ｒ₁乃至Ｒ₁₄は、それぞれ水素原子、アルキル基、置換あるいは無置換のアラルキル基、置換あるいは無置換のアリール基、置換あるいは無置換の複素環基、置換アミノ基又はハロゲン原子を表す。）

(In the formula [I], R _{1 to} R ₁₄ are each a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted amino group, or Represents a halogen atom.)

  According to the present invention, it is possible to provide a durable organic light-emitting device having a light output with high efficiency and high brightness. That is, the organic light emitting device using the fused ring aromatic compound of the present invention as a host or guest of the light emitting layer can emit light with high luminance and has excellent durability.

  Moreover, according to this invention, the organic light emitting element which can be manufactured easily and can be produced comparatively cheaply can be provided.

  Hereinafter, the present invention will be described in detail.

  First, the condensed ring aromatic compound of the present invention will be described. The condensed ring aromatic compound of the present invention is a compound represented by the following general formula [I].

In the formula [I], R _{1 to} R ₁₄ are each a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted amino group, or a halogen. Represents an atom.

Examples of the alkyl group represented by R _{1 to} R ₁₄ include a methyl group, an ethyl group, a normal propyl group, an isopropyl group, a normal butyl group, a tertiary butyl group, an octyl group, a cyclohexyl group, and a trifluoromethyl group.

Examples of the aralkyl group represented by R _{1 to} R ₁₄ include a benzyl group and a phenethyl group.

As aryl groups represented by R _{1 to} R ₁₄ , phenyl group, biphenyl group, terphenyl group, fluorenyl group, naphthyl group, fluoranthenyl group, anthryl group, phenanthryl group, pyrenyl group, tetracenyl group, pentacenyl group, triphenylenyl Group, perylenyl group and the like.

Examples of the heterocyclic group represented by R _{1 to} R ₁₄ include thienyl group, pyrrolyl group, pyridyl group, oxazolyl group, oxadiazolyl group, thiazolyl group, thiadiazolyl group, tertienyl group, quinolyl group, isoquinolyl group, carbazolyl group and the like. .

Examples of the substituted amino group represented by R _{1 to} R ₁₄ include a dimethylamino group, a diethylamino group, a dibenzylamino group, a diphenylamino group, a ditolylamino group, and a dianisolylamino group.

Examples of the halogen atom represented by R _{1 to} R ₁₄ include fluorine, chlorine, bromine, iodine and the like.

  As the substituents that the aralkyl group, aryl group and heterocyclic group may further have, an alkyl group such as a methyl group, an ethyl group, a normal propyl group, an isopropyl group, a tertiary butyl group, a cyclohexyl group, a benzyl group, Aralkyl groups such as phenethyl group, aryl groups such as phenyl group and biphenyl group, heterocyclic groups such as thienyl group, pyrrolyl group and pyridyl group, dimethylamino group, diethylamino group, dibenzylamino group, diphenylamino group, ditolylamino group, Substituted amino groups such as dianisolylamino group, alkoxyl groups such as methoxyl group, ethoxyl group, propoxyl group, aryloxyl groups such as phenoxyl group, halogen atoms such as fluorine, chlorine, bromine and iodine, cyano group, etc. Can be mentioned.

  Although there is no restriction | limiting in particular about the method to manufacture the condensed ring aromatic compound of this invention, For example, it can manufacture by the method shown below.

When the fused ring aromatic compound of the present invention is produced by this method, R ₂ , R ₇ , R ₁₀ and R in the general formula [I] are preferably used from the viewpoint of the stability of the intermediate 2 and the intermediate 5. _The substituent corresponding to ₁₃ is a substituted or unsubstituted aryl group.

  In addition, since the condensed ring aromatic compound of the present invention has a relatively large condensed ring as a main skeleton, when used as a constituent material of an organic light emitting device, particularly as a light emitting material, in order to suppress concentration quenching of the light emitting material. It preferably has a substituent having a large steric hindrance.

  Hereinafter, specific structural formulas of the organic compounds used in the present invention are shown below. However, these are merely representative examples, and the present invention is not limited thereto.

  Next, the organic light emitting device of the present invention will be described in detail.

  The organic light emitting device of the present invention includes an anode, a cathode, and a layer made of an organic compound sandwiched between the anode and the cathode. The organic light-emitting device of the present invention preferably emits light by applying a voltage between the anode and the cathode.

  Hereinafter, the organic light-emitting device of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a first embodiment of the organic light-emitting device of the present invention. In the organic light emitting device 10 of FIG. 1, an anode 2, a light emitting layer 3, and a cathode 4 are sequentially provided on a substrate 1. This organic light emitting device 10 is useful when the light emitting layer 3 is composed of an organic compound having all of hole transport ability, electron transport ability, and light emitting performance. Further, it is also useful when an organic compound having any one of the characteristics of hole transport ability, electron transport ability and light emitting performance is mixed.

  FIG. 2 is a cross-sectional view showing a second embodiment of the organic light emitting device of the present invention. In the organic light emitting device 20 of FIG. 2, an anode 2, a hole transport layer 5, an electron transport layer 6 and a cathode 4 are sequentially provided on a substrate 1. This organic light emitting device 20 is useful when a light emitting organic compound having either a hole transporting property or an electron transporting property and an organic compound having only an electron transporting property or only a hole transporting property are used in combination. . In the organic light emitting device 20, the hole transport layer 5 or the electron transport layer 6 also serves as a light emitting layer.

  FIG. 3 is a cross-sectional view showing a third embodiment of the organic light-emitting device of the present invention. The organic light emitting device 30 in FIG. 3 is obtained by inserting the light emitting layer 3 between the hole transport layer 5 and the electron transport layer 6 in the organic light emitting device 20 in FIG. The organic light emitting device 30 has functions of separating carrier transport and light emission, and organic compounds having hole transport property, electron transport property, and light emission property can be used in appropriate combination. For this reason, the degree of freedom of material selection is greatly increased, and various compounds having different emission wavelengths can be used, so that the emission hue can be diversified. Furthermore, it is possible to effectively confine each carrier or exciton in the central light emitting layer 3 to improve the light emission efficiency of the organic light emitting device 30.

  FIG. 4 is a cross-sectional view showing a fourth embodiment of the organic light emitting device of the present invention. An organic light emitting device 40 in FIG. 4 is obtained by providing a hole injection layer 7 between the anode 2 and the hole transport layer 5 in the organic light emitting device 30 in FIG. 3. Since the organic light emitting element 40 is provided with the hole injection layer 7, the adhesion between the anode 2 and the hole transport layer 5 or the hole injection property is improved. It is.

  FIG. 5 is a cross-sectional view showing a fifth embodiment of the organic light-emitting device of the present invention. The organic light emitting device 50 shown in FIG. 5 has a layer (hole / exciton blocking layer 8) that prevents holes or excitons (excitons) from passing to the cathode 4 side in the organic light emitting device 30 shown in FIG. 3 and the electron transport layer 6. By using an organic compound having a very high ionization potential as the hole / exciton blocking layer 8, the light emission efficiency of the organic light emitting device 50 is improved.

  FIG. 6 is a cross-sectional view showing a sixth embodiment of the organic light emitting device of the present invention. The organic light emitting device 60 of FIG. 6 is obtained by inserting the hole / exciton blocking layer 8 between the light emitting layer 3 and the electron transport layer 6 in the organic light emitting device 40 of FIG. By using a compound having a very high ionization potential as the hole blocking layer 8, the light emission efficiency of the organic light emitting device 60 is improved.

  However, FIG. 1 to FIG. 6 are very basic device configurations, and the configuration of the organic light emitting device using the condensed ring aromatic compound of the present invention is not limited to these. For example, various layer configurations such as providing an insulating layer, an adhesive layer, or an interference layer at the interface between the electrode and the organic layer, and the hole transport layer including two layers having different ionization potentials can be employed.

  The condensed ring aromatic compound of the present invention is a compound having excellent light-emitting properties and durability as compared with conventional compounds, and can be used in any form of FIGS.

  In the organic light-emitting device of the present invention, at least one kind of the condensed ring aromatic compound of the present invention is contained in a layer made of an organic compound. Here, the layer made of an organic compound specifically refers to the light emitting layer 3, the hole transport layer 5, the electron transport layer 6, the hole injection layer 7 or the hole / exciton blocking layer shown in FIGS. 8. Preferably, the light emitting layer 3 contains the condensed ring aromatic compound of the present invention. In the organic light emitting device of the present invention, the fused ring aromatic compound of the present invention may be contained only in a single layer or in a plurality of layers. Moreover, the condensed ring aromatic compound of this invention may be contained 1 type per layer, and may be contained 2 or more types.

  In the organic light emitting device of the present invention, the light emitting layer 3 is preferably composed of a host and a guest. Here, the fused ring aromatic compound of the present invention may be used as a host or a guest. Here, the guest refers to a compound that emits light in response to recombination of holes and electrons in the light emitting region of the organic light emitting device, and is included in a substance (host) that forms the light emitting region.

When the light emitting layer is composed of a carrier transporting host and guest, the main process leading to light emission is composed of the following several processes.
1. Transport of electrons and holes in the light emitting layer.
2. Host exciton generation.
3. Excitation energy transfer between host molecules.
4). Excitation energy transfer from host to guest.

  Desired energy transfer and light emission in each process occur through various deactivation processes and competition.

  Needless to say, in order to increase the light emission efficiency of the organic light emitting device, the emission center material itself has a high emission quantum yield. However, how to efficiently transfer energy between the host and the host or between the host and the guest is also a big problem. Further, although the cause of light emission deterioration due to energization is not clear at present, it is assumed that it is related to the environmental change of the light emitting material due to at least the light emission center material itself or its peripheral molecules.

  Therefore, when the fused ring aromatic compound of the present invention is used as a guest in the light emitting layer, the light emitting efficiency of the device is improved, high luminance is maintained for a long period of time, and deterioration of energization is reduced.

  When the fused ring aromatic compound of the present invention is used as a guest, the content thereof is preferably 0.1% by weight or more and 30% by weight or less, and more preferably 0.1% from the viewpoint of concentration quenching suppression. % By weight or more and 15% by weight or less.

  On the other hand, when the fused ring aromatic compound of the present invention is used as a host, the guest is not particularly limited, and the guest can be appropriately used depending on the desired emission color or the like. In addition to the light-emitting material that serves as a guest, a hole-transporting compound, an electron-transporting compound, or the like can be doped together as necessary.

  As described above, the fused ring aromatic compound of the present invention is used as a material constituting a layer made of an organic compound, particularly a light emitting layer, and is used as a material constituting a layer other than the light emitting layer, if necessary. be able to. For example, it can be used as a material constituting a hole injection layer, a hole transport layer, an electron injection layer, an electron transport layer, an electron barrier layer, or the like.

  As described above, the organic light-emitting device of the present invention uses the condensed ring aromatic compound of the present invention as a component of the electron transport layer and the light-emitting layer. A luminescent compound, an electron transporting compound, and the like can be used together as necessary.

  Examples of these compounds are given below.

  The anode material should have a work function as large as possible. For example, a simple metal such as gold, platinum, nickel, palladium, cobalt, selenium, vanadium, or an alloy combining these simple metals can be used. Metal oxides such as tin oxide, zinc oxide, indium tin oxide (ITO), and indium zinc oxide can also be used. Conductive polymers such as polyaniline, polypyrrole, polythiophene and polyphenylene sulfide can also be used. These electrode materials may be used alone or in combination of two or more.

  On the other hand, a cathode material having a small work function is preferable. For example, a single metal such as lithium, sodium, potassium, cesium, calcium, magnesium, aluminum, indium, silver, lead, tin, chromium, or an alloy in which a plurality of these metals are combined can be used. It is also possible to use metal oxidation such as indium tin oxide (ITO). Moreover, the cathode may be composed of a single layer or a plurality of layers.

  Although it does not specifically limit as a board | substrate used with the organic light emitting element of this invention, Transparent substrates, such as opaque board | substrates, such as a metal board | substrate and a ceramic board | substrate, glass, quartz, a plastic sheet, can be used. It is also possible to control the color light by using a color filter film, a fluorescent color conversion filter film, a dielectric reflection film or the like on the substrate.

  Note that a protective layer or a sealing layer can be provided for the manufactured element for the purpose of preventing contact with oxygen, moisture, or the like. Examples of the protective layer include diamond thin films, inorganic material films such as metal oxides and metal nitrides, polymer films such as fluorine resin, polyparaxylene, polyethylene, silicone resin, polystyrene resin, and photo-curing resins. It is done. Further, it is possible to cover glass, a gas-impermeable film, a metal, etc., and to package the element itself with an appropriate sealing resin.

  In the organic light-emitting device of the present invention, the layer containing the compound represented by the general formula [I] and the layer containing another organic compound are generally formed into a thin film by a vacuum evaporation method or a coating method by dissolving in an appropriate solvent. Form. In particular, when a film is formed by a coating method, the film can be formed in combination with an appropriate binder resin.

  The binder resin can be selected from a wide range of binder resins. For example, polyvinyl carbazole resin, polycarbonate resin, polyester resin, polyarylate resin, polystyrene resin, acrylic resin, methacrylic resin, butyral resin, polyvinyl acetal resin, diallyl phthalate resin, phenol resin, epoxy resin, silicone resin, polysulfone resin, urea resin However, it is not limited to these. Moreover, these resin may be used individually or as a copolymer polymer, and may be used individually by 1 type, or 2 or more types may be mixed and used for it.

  In the organic light-emitting device of the present invention, a layer containing the condensed ring aromatic compound of the present invention is formed between the anode and the cathode by a vacuum deposition method or a solution coating method. The film thickness of the layer containing the condensed ring aromatic compound of the present invention is preferably less than 10 μm, more preferably 0.5 μm or less, and still more preferably 0.01 μm or more and 0.5 μm or less.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

  Example 1 [Exemplary Compound No. Synthesis of A-4]

(1) Synthesis of Intermediate A To a reaction vessel substituted with argon, 52.8 g (0.34 mol) of acenaphthene and 4.5 L of carbon disulfide were added, and the solution was cooled to 0 ° C. in an ice bath. Next, after adding 75.0 g (0.35 mol) of oxalyl bromide to this reaction solution, 187.5 g (0.70 mol) of anhydrous aluminum bromide was slowly added, followed by stirring for 1 hour. Next, after returning the reaction solution to room temperature, carbon disulfide was removed by decantation. Next, 3 L of 10% HCl solution was added in an ice bath and stirred for 2 hours. Thereafter, the solution was filtered, and the obtained solid was washed successively with methanol and isopropyl ether to obtain a brown solid. This solid was dissolved in chloroform, purified by silica gel chromatography (developing solvent: chloroform), and then recrystallized from chloroform to obtain 16.4 g (78.8 mmol, yield 23%) of intermediate A. .

(2) Synthesis of Intermediate B The following reagents and solvent were charged in a reaction vessel.
Intermediate A: 10.0 g (48 mmol)
Ethanol: 150ml
Toluene: 15ml

  Next, 10.0 g (48 mmol) of 1,3-diphenyl-2-propanone was added to the reaction solution, and then 20 ml of 6N aqueous KOH solution was slowly added dropwise. Next, the reaction solution was heated and stirred in an oil bath at 80 ° C. for 15 minutes. After completion of the reaction, the reaction solution is returned to room temperature, a small amount of water is added and filtered, and the resulting crystals are washed successively with water, methanol and isopropyl ether, and then dried under reduced pressure to obtain Intermediate B 15 0.8 g (41.4 mmol, yield 86%) was obtained.

(3) Synthesis of Intermediate C The following reagents and solvent were charged in a reaction vessel.

Intermediate B: 8.0 g (21 mmol)
1,2-dichloroethane: 160 ml
Benzenediazonium-2-carboxylate hydride: 4.0 g (23 mmol)
Propylene oxide: 5.0 g (83 mmol)

  Next, the reaction solution was heated and stirred in an oil bath at 80 ° C. for 1 hour. After completion of the reaction, the reaction solution was returned to room temperature, and then the solvent was distilled off under reduced pressure to obtain a brown solid. This solid was purified by silica gel chromatography (developing solvent: chloroform / hexane = 1/2) and then recrystallized from chloroform / ethanol to obtain 7.0 g (15.6 mmol, 75% yield) of intermediate C. )Obtained.

(4) Synthesis of Intermediate D The following reagents and solvent were charged in a reaction vessel.
Intermediate C: 5.0 g (12 mmol)
Chlorobenzene: 260ml
Benzene Serenic Anhydride (purity 70%, manufactured by Aldrich): 8.5 g (23 mmol)

  Next, the reaction solution was heated and stirred in an oil bath at 135 ° C. for 12 hours. After completion of the reaction, the reaction solution was returned to room temperature, and then the solvent was distilled off under reduced pressure to obtain a reddish brown solid. This solid was purified by silica gel chromatography (developing solvent: chloroform / hexane = 1/5) to obtain 4.9 g (10.8 mmol, yield 90%) of Intermediate D.

(5) Synthesis of Intermediate E The following reagents and solvent were charged in a reaction vessel.
Intermediate D: 4.0 g (7.0 mmol)
Ethanol: 50ml
Toluene: 5ml

  Next, 2.0 g (7.0 mmol) of 1,3-diphenyl-2-propanone was added to the reaction solution, and then 4 ml of 6N aqueous KOH solution was slowly added dropwise. Next, the reaction solution was heated and stirred in an oil bath at 80 ° C. for 30 minutes. After completion of the reaction, the reaction solution was returned to room temperature, a small amount of water was added and filtered, and the resulting crystals were washed successively with water, methanol, and isopropyl ether. Thereafter, the washed crystal was dried under reduced pressure to obtain 4.0 g (5.0 mmol, yield 71%) of Intermediate E.

(6) Exemplified Compound No. Synthesis of A-4 The following reagents and solvent were charged in a reaction vessel.
Intermediate E: 2.0 g (3.2 mmol)
Xylene: 30ml
Norbornane-2,5-diene: 0.9 g (10 mmol)

  Next, the reaction solution was heated in a 130 ° C. oil bath for 40 hours. After completion of the reaction, the reaction solution was returned to room temperature and then filtered to obtain a brown solid. This solid was purified by silica gel chromatography (developing solvent: chloroform) and then purified by sublimation, whereby Exemplified Compound No. 1.26 g (2.0 mmol, yield 63%) of A-4 was obtained.

  630.2 which is M + of this compound was confirmed by MALDI-TOF MS (matrix-assisted ionization-time-of-flight mass spectrometry).

  Moreover, the structure of this compound was confirmed by NMR measurement.

¹ H-NMR (CDCl ₃ , 500 MHz) σ (ppm): 7.62-7.52 (m, 10H), 7.51-7.42 (m, 12H), 7.29 (m, 2H), 7.11 (s, 2H), 6.78 (d, 2H), 6.16 (d, 2H).

  Example 2 [Exemplary Compound No. Synthesis of B-7]

The following reagents and solvent were charged in the reaction vessel.
Intermediate E: 2.0 g (3.2 mmol)
Xylene: 30ml
Ethynylbenzene: 0.33 g (3.2 mmol)

  Next, the reaction solution was heated and stirred in an oil bath at 130 ° C. for 8 hours. After completion of the reaction, the reaction solution was returned to room temperature and then filtered to obtain a brown solid. This solid was purified by silica gel chromatography (eluent: chloroform), and then purified by sublimation, whereby Exemplified Compound No. 1.62 g (2.3 mmol, yield 72%) of B-7 was obtained.

  706.3 which is M + of this compound was confirmed by MALDI-TOF MS (matrix-assisted ionization-time-of-flight mass spectrometry).

  Moreover, the structure of this compound was confirmed by NMR measurement.

¹ H-NMR (CDCl ₃ , 500 MHz) σ (ppm): 7.62-7.52 (m, 8H), 7.51-7.42 (m, 9H), 7.29 (m, 7H), 7.14 (m, 6H), 6.85 (d, 1H), 6.25 (d, 1H), 6.17 (m, 1H), 6.12 (s, 1H).

  Example 3 [Exemplary Compound No. Synthesis of B-8]

The following reagents and solvents were charged in the reaction vessel.
Intermediate E: 2.0 g (3.2 mmol)
Xylene: 30ml
Diphenylacetylene: 0.57 g (3.2 mmol)

  Next, the reaction solution was heated and stirred in an oil bath at 130 ° C. for 40 hours. After completion of the reaction, the reaction solution was returned to room temperature and then filtered to obtain a brown solid. Next, this solid was purified by silica gel chromatography (developing solvent: chloroform), and then purified by sublimation, whereby Example Compound No. 1.75 g (2.2 mmol, yield 70%) of B-8 was obtained.

  782.3 which is M + of this compound was confirmed by MALDI-TOF MS (matrix-assisted ionization-time-of-flight mass spectrometry).

  Moreover, the structure of this compound was confirmed by NMR measurement.

¹ H-NMR (CDCl ₃ , 500 MHz) σ (ppm): 7.62-7.52 (m, 6H), 7.51-7.42 (m, 6H), 7.29 (m, 2H), 7.11 (m, 10H), 6.84 (m, 10H), 6.17 (d, 2H), 6.11 (d, 2H).
Example 4 [Exemplary Compound No. Synthesis of C-20]

(1) Synthesis of Intermediate F The following reagents and solvent were charged in a reaction vessel.
Intermediate D: 4.0 g (7.0 mmol)
Ethanol: 50ml
Toluene: 5ml

  Next, after adding 3.0 g (7.0 mmol) of 1,3-bis (3,5-ditertiarybutylphenyl) propan-2-one, 4 ml of 6N KOH aqueous solution was slowly added dropwise. Next, the reaction solution was heated and stirred in an oil bath at 80 ° C. for 30 minutes. After completion of the reaction, the reaction solution was returned to room temperature, a small amount of water was added and filtered. Next, the obtained crystals were washed successively with water, methanol, and isopropyl ether, and then dried under reduced pressure to obtain 4.0 g of Intermediate F (4.9 mmol, yield 70%).

(2) Exemplified Compound No. Synthesis of C-20 The following reagents and solvents were charged into a reaction vessel.
Intermediate F: 2.0 g (2.3 mmol)
Xylene: 20ml
Norbornane-2,5-diene: 0.9 g (10 mmol)

  Next, the reaction solution was heated in a 130 ° C. oil bath for 40 hours. After completion of the reaction, the reaction solution was returned to room temperature and then filtered to obtain a brown solid. This solid was purified by silica gel chromatography (developing solvent: chloroform) and then purified by sublimation, whereby Exemplified Compound No. 1.28 g (1.5 mmol, 66% yield) of C-20 was obtained.

  854.5 which is M + of this compound was confirmed by MALDI-TOF MS (matrix-assisted ionization-time-of-flight mass spectrometry).

  Moreover, the structure of this compound was confirmed by NMR measurement.

¹ H-NMR (CDCl ₃ , 500 MHz) σ (ppm): 7.61-7.52 (m, 6H), 7.51-7.42 (m, 8H), 7.45 (d, 4H), 7.29 (m, 2H), 7.17 (s, 2H), 6.85 (d, 2H), 6.12 (d, 2H), 1.36 (s, 36H).

Example 5 [Production of Organic Light-Emitting Element]
The organic light emitting device shown in FIG. 3 was produced by the following method.

  First, indium tin oxide (ITO) was formed as an anode 2 on a glass substrate (substrate 1) with a film thickness of 120 nm by a sputtering method. Next, the substrate was successively subjected to ultrasonic cleaning with acetone and isopropyl alcohol (IPA), then boiled and cleaned with IPA, and then dried. Further, it was washed with UV / ozone. The substrate thus treated was used as a transparent conductive support substrate.

  Next, on the transparent conductive support substrate, a chloroform solution of Compound 1 shown below was formed into a film with a thickness of 20 nm by spin coating to form a hole transport layer 5.

Next, other organic layers and electrode layers were vacuum-deposited by resistance heating in a vacuum chamber of 10 ⁻⁵ Pa to continuously form a device.

  Specifically, first, as the light emitting layer 3, the compound 2 shown below as a host and the exemplified compound No. 1 as a guest. A-4 is referred to as Compound 2 and Exemplified Compound No. Co-evaporation was performed so that the weight concentration ratio of A-4 was 98: 2. At this time, the thickness of the light emitting layer 3 was 20 nm. Next, a compound 3 shown below was formed as an electron transport layer 6 with a film thickness of 30 nm. Next, LiF was formed to a thickness of 0.5 nm as the first metal electrode layer. Finally, Al was formed to a thickness of 150 nm as the second metal electrode layer. The first metal electrode layer (LiF film) and the second metal electrode layer (Al film) function as the cathode 4. As described above, an organic light emitting device was obtained.

  When a voltage of 6.0 V was applied to the organic light emitting device of this example, green light emission was observed. Furthermore, when this element was continuously energized in a nitrogen atmosphere, stable light emission was obtained even when energized continuously for 100 hours.

Example 6
In Example 5, as the guest of the light emitting layer 3, Exemplified Compound No. In place of A-4, Exemplified Compound No. A device was fabricated in the same manner as in Example 5 except that B-7 was used and the light emitting layer 3 was formed such that the weight concentration ratio of the host and guest was 90:10.

  When an applied voltage of 6.0 V was applied to the organic light emitting device of this example, yellow-green light emission was observed. Furthermore, when this element was continuously energized in a nitrogen atmosphere, stable light emission was obtained even when energized continuously for 100 hours.

Example 7
In Example 5, as the guest of the light emitting layer 3, Exemplified Compound No. In place of A-4, Exemplified Compound No. A device was fabricated in the same manner as in Example 5 except that B-8 was used and the light emitting layer 3 was formed so that the weight concentration ratio of the host and guest was 85:15.

When an applied voltage of 6.0 V was applied to the organic light emitting device of this example, yellow-green light emission was observed. Furthermore, when this element was continuously energized in a nitrogen atmosphere, stable light emission was obtained even when energized continuously for 100 hours.
Example 8
In Example 5, as the guest of the light emitting layer 3, Exemplified Compound No. In place of A-4, Exemplified Compound No. A device was fabricated in the same manner as in Example 5 except that C-20 was used and the light emitting layer 3 was formed such that the weight concentration ratio of the host and guest was 90:10.

  In the organic light emitting device of this example, green light emission was observed when an applied voltage of 6.0 V was applied. Furthermore, when this element was continuously energized in a nitrogen atmosphere, stable light emission was obtained even when energized continuously for 100 hours.

It is sectional drawing which shows 1st embodiment in the organic light emitting element of this invention. It is sectional drawing which shows 2nd embodiment in the organic light emitting element of this invention. It is sectional drawing which shows 3rd embodiment in the organic light emitting element of this invention. It is sectional drawing which shows 4th embodiment in the organic light emitting element of this invention. It is sectional drawing which shows 5th embodiment in the organic light emitting element of this invention. It is sectional drawing which shows 6th embodiment in the organic light emitting element of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Anode 3 Light emitting layer 4 Cathode 5 Hole transport layer 6 Electron transport layer 7 Hole injection layer 8 Hole / exciton blocking layer 10, 20, 30, 40, 50, 60 Organic light emitting device

Claims (6)

A condensed ring aromatic compound represented by the following general formula [I]:

(In the formula [I], R _{1 to} R ₁₄ are each a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted amino group, or Represents a halogen atom.) The condensed ring aromatic compound according to claim 1, wherein R ₂ , R ₇ , R ₁₀ and R ₁₃ are substituted or unsubstituted aryl groups. An anode and a cathode;
A layer made of an organic compound sandwiched between the anode and the cathode, and
An organic light-emitting device comprising at least one kind of the condensed ring aromatic compound according to claim 1 or 2 in the layer made of the organic compound.   The organic light emitting device according to claim 3, wherein the condensed ring aromatic compound is contained in a light emitting layer.   The organic light-emitting device according to claim 3 or 4, wherein the light-emitting layer comprises a guest and a host, and the fused ring aromatic compound is a guest.   The organic light-emitting device according to claim 3, wherein the organic light-emitting device emits light by applying a voltage between the anode and the cathode.

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