JP2002069061A - Oxazole compound and organic light emitting element using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new oxazole compound suitable as an organic layer for an organic light emitting element. SOLUTION: This oxazole compound is represented by general formula [I] (X1, X2 and X3 are each an alkyl group, a substituted or nonsubstituted aralkyl group, a substituted or nonsubstituted vinyl group, a substituted or nonsubstituted aryl group, a substituted or nonsubstituted heterocyclic group or a substituted carbonyl group; X1, X2 and X3 may be the same or different and X2 and X3 may form a ring).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a novel organic compound and an organic light emitting device using the same.

[0002]

2. Description of the Related Art In an organic light emitting device, a thin film containing a fluorescent organic compound is sandwiched between an anode and a cathode, and electrons and holes (holes) are injected from each electrode to exciton the fluorescent compound. It is an element that utilizes light emitted when this exciton is returned to the ground state.

In 1987, a study by Kodak Company (Appl.
Phys. Lett. 51, 913 (1987)), a function-separated type 2 using ITO as an anode, magnesium-silver alloy as a cathode, an aluminum quinolinol complex as an electron transporting material and a luminescent material, and a triphenylamine derivative as a hole transporting material. This device has a layered structure, and has an applied voltage of about 10 V and 1000 cd / m ^2.
A degree of luminescence has been reported. Related patents include U.S. Pat. No. 4,539,507 and U.S. Pat.
No. 32, U.S. Pat. No. 4,885,211 and the like.

[0004] In addition, by changing the type of the fluorescent organic compound, light emission from ultraviolet to infrared can be achieved, and various compounds have recently been actively studied. For example, US Pat. No. 5,151,629 and US Pat.
9,783, U.S. Pat. No. 5,382,477, JP-A-2-247278, JP-A-3-255190, JP-A-5-202356, JP-A-9-202
No. 878, Japanese Patent Application Laid-Open No. 9-227576, and the like.

[0005] In addition to the organic light-emitting device using the above low-molecular material, an organic light-emitting device using a conjugated polymer is also a group of Cambridge University (Nature,
347, 539 (1990)).
In this report, light emission was confirmed in a single layer by forming a film of polyphenylenevinylene (PPV) in a coating system.

US Pat. No. 5,247,190, US Pat. No. 5,514,878, and US Pat. No. 5,672,678 are related patents for organic light emitting devices using conjugated polymers.
JP-A-4-145192, JP-A-5-247
No. 460, for example.

As described above, recent advances in organic light-emitting elements are remarkable, and the characteristics thereof are that high luminance, a variety of emission wavelengths, high-speed response, a thin and lightweight light-emitting device can be realized at a low applied voltage. It suggests potential for a wide range of applications.

However, at present, light output with higher luminance or higher conversion efficiency is required. In addition, there are still many problems in terms of durability such as a change with time due to long-term use and deterioration due to an atmospheric gas containing oxygen or moisture. Further, when application to a full-color display or the like is considered, light emission of blue, green, and red with good color purity is required, but this problem is not yet sufficient.

As the fluorescent organic compound used for the electron transport layer, the light emitting layer, etc., many compounds having a heterocyclic ring have been studied. For example, a pyrrole compound, a thiophene compound, an oxazole compound, an oxadiazole compound and the like can be mentioned, and among these, there are many reports of an oxazole compound having a relatively strong electron acceptor property and a good electron transport property. For example, Japanese Patent Application Laid-Open No. 5-214
JP-A-335, JP-A-9-188876 and JP-A-11-345686 are mentioned, but none of them have satisfactory light emission luminance and durability.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel oxazole compound.

Another object of the present invention is to provide an organic light-emitting device using the oxazole compound and having extremely high efficiency, high luminance and long life light output. Another object of the present invention is to provide an organic light-emitting device that has various emission wavelengths, exhibits various emission hues, and is extremely durable. Another object of the present invention is to provide an organic light emitting device that can be easily manufactured and can be manufactured at relatively low cost.

[0012]

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

[0013]

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(Wherein X ₁ , X ₂ and X ₃ are an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted vinyl group, a substituted or unsubstituted aryl group,
Represents a substituted or unsubstituted heterocyclic group or substituted carbonyl group, and X ₁ , X ₂ and X ₃ may be the same or different. X ₂ and X ₃ may form a ring. )

The oxazole compound of the present invention is preferably an oxazole compound represented by the following general formulas [II] to [VII].

[0016]

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(In the formula, R ₁ and R ₄ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and R ₁ and R ₄ may be the same or different. R ₂ and R ₃ are hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, or cyano group, R ₂ and R ₃ are the same Or may be different.)

[0018]

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(Wherein R ₅ , R ₆ , R ₇ and R ₈ represent a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group Or a cyano group, wherein R ₅ , R ₆ , R
₇ and R ₈ may be the same or different. R ₉
Represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group. )

[0020]

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(Wherein R ₁₀ , R ₁₁ and R ₁₂ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and even if R ₁₀ , R ₁₁ and R ₁₂ are the same, R ₁₃ , R ₁₄ , R ₁₅ and R ₁₆ may be different
R ₁₃ represents a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group or a cyano group;
R ₁₄ , R ₁₅ and R ₁₆ may be the same or different. )

[0022]

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(Wherein R ₁₇ , R ₁₈ and R ₁₉ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and even if R ₁₇ , R ₁₈ and R ₁₉ are the same, Y may be ＝ C (R ₂₀ ) -C (R ₂₁ )
=, = C (R ₂₂₎ represents a -N = or = N-N =.
R _20, R ₂₁ and R ₂₂ represents a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, R _20, R ₂₁ and R ₂₂ may be the same or different. )

[0024]

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(Wherein R ₂₃ , R ₂₄ and R ₂₅ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and even if R ₂₃ , R ₂₄ and R ₂₅ are the same, May be different.)

[0026]

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Where R₂₆, R₂₇, R₂₈, R₂₉And R
₃₀Is a substituted or unsubstituted aryl group,
Represents an unsubstituted heterocyclic group;₂₆, R₂₇, R₂₈, R₂₉You
And R ₃₀May be the same or different. )

The organic light-emitting device of the present invention is an organic light-emitting device having at least a pair of electrodes comprising an anode and a cathode, and a layer containing one or more organic compounds sandwiched between the pair of electrodes. At least one layer containing a compound contains at least one of the oxazole compounds represented by the above general formula [I], preferably the above general formulas [II] to [VII].

In the organic light emitting device of the present invention, it is preferable that at least the electron transport layer or the light emitting layer among the layers containing the organic compound contains at least one of the oxazole compounds.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION The oxazole compound of the present invention
It is represented by the following general formula [I].

[0031]

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(Wherein X ₁ , X ₂ and X ₃ are an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted vinyl group, a substituted or unsubstituted aryl group,
Represents a substituted or unsubstituted heterocyclic group or substituted carbonyl group, and X ₁ , X ₂ and X ₃ may be the same or different. X ₂ and X ₃ may form a ring. )

The oxazole compound of the present invention is not particularly limited as long as it is represented by the above general formula [I], but is preferably one represented by the following general formulas [II] to [V]. In addition, among those represented by the following general formula [II], those represented by the following general formula [VI] are more preferable, and those represented by the following general formula [III] represented by the following general formula [VII] are more preferable. Is more preferred.

[0034]

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(In the formula, R ₁ and R ₄ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and R ₁ and R ₄ may be the same or different. R ₂ and R ₃ are hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, or cyano group, R ₂ and R ₃ are the same Or may be different.)

[0036]

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(Wherein R ₅ , R ₆ , R ₇ and R ₈ are a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group Or a cyano group, wherein R ₅ , R ₆ , R
₇ and R ₈ may be the same or different. R ₉
Represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group. )

[0038]

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(Wherein R ₁₀ , R ₁₁ and R ₁₂ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and even if R ₁₀ , R ₁₁ and R ₁₂ are the same, R ₁₃ , R ₁₄ , R ₁₅ and R ₁₆ may be different
R ₁₃ represents a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group or a cyano group;
R ₁₄ , R ₁₅ and R ₁₆ may be the same or different. )

[0040]

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(Wherein R ₁₇ , R ₁₈ and R ₁₉ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and even if R ₁₇ , R ₁₈ and R ₁₉ are the same, Y may be ＝ C (R ₂₀ ) -C (R ₂₁ )
=, = C (R ₂₂₎ represents a -N = or = N-N =.
R _20, R ₂₁ and R ₂₂ represents a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, R _20, R ₂₁ and R ₂₂ may be the same or different. )

[0042]

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(Wherein R ₂₃ , R ₂₄ and R ₂₅ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and even if R ₂₃ , R ₂₄ and R ₂₅ are the same, May be different.)

[0044]

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(Where R₂₆, R₂₇, R₂₈, R₂₉And R
₃₀Is a substituted or unsubstituted aryl group,
Represents an unsubstituted heterocyclic group;₂₆, R₂₇, R₂₈, R₂₉You
And R ₃₀May be the same or different. )

Specific examples of the substituents in the above general formulas [I] to [VII] are shown below.

Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a ter-butyl group and an octyl group.

Examples of the aralkyl group include a benzyl group and a phenethyl group.

Examples of the aryl group include a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, an anthryl group,
Examples include a phenanthryl group, a fluorenyl group and a pyrenyl group.

Examples of the heterocyclic group include a thienyl group, a pyrrolyl group, a pyridyl group, a quinolyl group, a carbazolyl group, an oxazolyl group, an oxadiazolyl group, a terthienyl group and a terpyrrolyl group.

Examples of the substituent which the above substituent may have include an alkyl group such as a methyl group, an ethyl group and a propyl group, an aralkyl group such as a benzyl group and a phenethyl group, a phenyl group, a naphthyl group, an anthryl group and a fluorenyl group. Group, aryl group such as pyrenyl group, thienyl group, pyrrolyl group, pyridyl group, heterocyclic group such as quinolyl group, diethylamino group, dibenzylamino group, diphenylamino group, amino group such as ditolylamino group, methoxyl group,
Examples include an alkoxyl group such as an ethoxyl group, a propoxydyl group, and a phenoxyl group, a cyano group, and a nitro group.

Next, typical examples of the oxazole compound of the present invention are shown below, but the present invention is not limited to these.

[0053]

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[0054]

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[0055]

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[0056]

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[0057]

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[0058]

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The oxazole compound of the present invention can be synthesized by a generally known method, for example, by a 1,3 dipolar cycloaddition reaction of nitrile oxide with an unsaturated carbon bond.
An oxazole compound having a formyl group or a carbonyl group can be synthesized as an intermediate, and a substituent can be added to the oxazole compound to obtain an oxazole compound having various substituents.

The oxazole compounds represented by the general formulas [I] to [VII] of the present invention are excellent in electron transporting property, light emitting property and durability as compared with conventional compounds. The layer containing the compound is particularly useful as an electron transporting layer and a light emitting layer, and a layer formed by a vacuum evaporation method, a solution coating method, or the like hardly causes crystallization or the like and has excellent stability over time.

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

The organic light emitting device of the present invention is an organic light emitting device having at least a pair of electrodes consisting of an anode and a cathode, and at least a layer containing one or more organic compounds sandwiched between the pair of electrodes. At least one of the layers containing the general formula [I], preferably the general formula [I]
It is characterized by containing at least one of the oxazole compounds represented by I] to [VII].

In the organic light emitting device of the present invention, it is preferable that at least the electron transporting layer or the light emitting layer among the layers containing the organic compound contains at least one of the oxazole compounds.

In the organic light emitting device of the present invention, the oxazole compounds represented by the above general formulas [I] to [VII] are formed between the anode and the cathode by a vacuum deposition method or a solution coating method. The thickness of the organic layer is less than 10 μm, preferably 0.5 μm or less, more preferably 0.01 to 0.5 μm.
It is preferable to make the film thin to a thickness of μm.

FIGS. 1 to 3 show preferred examples of the organic light emitting device of the present invention.

FIG. 1 is a sectional view showing an example of the organic light emitting device of the present invention. FIG. 1 shows a structure in which an anode 2, a light emitting layer 3 and a cathode 4 are sequentially provided on a substrate. The light-emitting element used here is useful when it has a single hole-transporting ability, electron-transporting ability, and light-emitting performance, or when a mixture of compounds having the respective properties is used.

FIG. 2 is a sectional view showing another example of the organic light emitting device of the present invention. FIG. 2 shows a configuration in which an anode 2, a hole transport layer 5, an electron transport layer 6, and a cathode 4 are sequentially provided on a substrate 1. In this case, when the luminescent material has a hole transporting property or an electron transporting property or a material having both functions in each layer, and is used in combination with a mere hole transporting substance having no light emitting property or an electron transporting substance Useful for In this case, the light emitting layer 3 is made of either the hole transport layer 5 or the electron transport layer 6.

FIG. 3 is a sectional view showing another example of the organic light emitting device of the present invention. FIG. 3 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. It separates the functions of carrier transport and light emission, and is used in a timely combination with a compound having hole transport, electron transport, and light emitting properties. Can be used, so that the emission hue can be diversified. Further, it is possible to effectively confine each carrier or exciton in the central light emitting layer 3 to improve the luminous efficiency.

However, FIGS. 1 to 3 show only very basic device configurations, and the configuration of an organic light-emitting device using the compound of the present invention is not limited to these. For example, various layer configurations such as providing an insulating layer at the interface between the electrode and the organic layer, providing an adhesive layer or an interference layer, and forming the hole transport layer from two layers having different ionization potentials can be employed.

The general formulas [I] to [VI] used in the present invention
The oxazole compound represented by I] is a compound having excellent electron transporting property, light emitting property and durability as compared with conventional compounds, and can be used in any of the forms shown in FIGS.

In particular, an organic layer using the oxazole compound of the present invention is useful as an electron transporting layer and a light emitting layer, and a layer formed by a vacuum evaporation method, a solution coating method, or the like is unlikely to cause crystallization or the like and is stable with time. Excellent in nature.

In the present invention, the oxazole compounds represented by the general formulas [I] to [VII] are used as components of the electron transporting layer and the light emitting layer. Compounds or electron transporting compounds can be used together if necessary.

The following are examples of these compounds.

[0074]

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[0075]

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[0076]

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[0077]

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[0078]

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[0079]

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[0080]

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[0081]

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[0082]

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[0083]

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[0084]

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In the organic light-emitting device of the present invention, the layer containing the oxazole compounds represented by the general formulas [I] to [VII] and the layer containing another organic compound are generally formed by a vacuum evaporation method or a suitable solvent. And a thin film is formed by a coating method. Especially when the film is formed by the coating method,
The film can also 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,
Examples include, but are not limited to, diallyl phthalate resin, phenol resin, epoxy resin, silicone resin, polysulfone resin, urea resin, and the like. These may be used alone or as a copolymer, alone or as a mixture of two or more.

The anode material preferably has a work function as large as possible. For example, simple metals such as gold, platinum, nickel, palladium, cobalt, selenium, and vanadium or alloys thereof, tin oxide, zinc oxide, indium tin oxide ( Metal oxides such as ITO) and indium zinc oxide can be used. In addition, conductive polymers such as polyaniline, polypyrrole, polythiophene, and polyphenylene sulfide can also be used. These electrode substances may be used alone or in combination of two or more.

On the other hand, it is preferable that the cathode material has a small work function, such as lithium, sodium, potassium, calcium, magnesium, aluminum, indium, silver, or the like.
It can be used as a single metal or a plurality of alloys such as lead, tin and chromium. It is also possible to use metal oxidation such as indium tin oxide (ITO). Further, the cathode may have a single-layer structure or a multilayer structure.

The substrate used in the present invention is not particularly limited, but an opaque substrate such as a metal substrate or a ceramic substrate, or a transparent substrate such as glass, quartz, or a plastic sheet is used. Further, it is also possible to control the emitted light by using a color filter film, a fluorescent color conversion filter film, a dielectric reflection film or the like on the substrate.

Incidentally, a protective layer or a sealing layer may be provided on the fabricated device for the purpose of preventing contact with oxygen, moisture, or the like. Examples of the protective layer include a diamond thin film, an inorganic material film such as a metal oxide and a metal nitride, a polymer film such as a fluorine resin, a polyparaxylene, a polyethylene, a silicone resin, and a polystyrene resin, and a photocurable resin. Can be Alternatively, the device itself can be covered with glass, a gas impermeable film, metal, or the like, and the element itself can be packaged with an appropriate sealing resin.

[0091]

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

Example 1 Compound no. Synthesis of 1 20 g of benzaldehyde in a 300 ml three-necked flask
(189 mmol) and 150 ml of ethanol, and stirred at 5 ° C. with hydroxylamine hydrochloride 13.8.
g (199 mmol) was added, and then an aqueous solution of 8.3 g (207 mmol) of sodium hydroxide in 50 ml of water was added dropwise. After stirring at room temperature for 3 hours, water was added, the organic layer was extracted with ethyl acetate, dried over anhydrous sodium sulfate, and the solvent was distilled off to obtain 22 g of oxime [1] (colorless liquid) (yield 9).
7%).

[0093]

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3.2 g (24.5 mmol) of phenylpropargylaldehyde, 4.5 g (36.8 mmol) of oxime [1] and 150 ml of dichloromethane were placed in a 300 ml three-necked flask, and stirred at 0 ° C. with antiformin (12% aqueous solution). 27.6 g (45 mmol) were added dropwise and then 0.5 ml of triethylamine was added.
After gradually raising the temperature and stirring at room temperature for 5 hours, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and then purified on a silica gel column to give an oxazole intermediate [2] (white crystals)
3.2 g was obtained (yield 51%).

[0095]

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In a 100 ml three-necked flask, 1.0 g (4.0 mmol) of the oxazole intermediate [2], 1.0 g (4.4 mmol) of the phosphonate compound and DM
To the mixture, 40 ml of F was added, and 0.55 g (4.8 mmol) of potassium t-butoxide was added with stirring at 5 ° C. After gradually raising the temperature and stirring at room temperature for 3 hours, water was added, the organic layer was extracted with ethyl acetate, dried over anhydrous sodium sulfate, and purified with a silica gel column. 1.0 g of 1 (white crystals) was obtained (80% yield).

[0097]

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Example 2 Compound no. Synthesis of 10 Oxime [3] (yellow crystal) was synthesized in the same manner as in Example 1.

[0099]

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In a 300 ml three-necked flask, 2.0 g (15.4 mmol) of phenylpropargylaldehyde, 7.3 g (23.1 mmol) of oxime [3] and 150 ml of dichloromethane were placed, and stirred at 0 ° C. with antiformin (12% aqueous solution). 17.2 g (27.7 mmo
l) was added dropwise and then 0.5 ml of triethylamine was added. After gradually heating and stirring at room temperature for 5 hours, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and then purified on a silica gel column to obtain 2.9 g of an oxazole intermediate [4] (yellow crystals) (yield). Rate 43%).

[0101]

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Dry THF 5 was placed in a 100 ml three-necked flask.
After adding 0 ml, and stirring at 5 ° C., 0.13 g (2.4 mmol) of sodium methoxide was added, and then 0.15 g (2.3 mmol) of dicyanomethylene was added.
After stirring for 30 minutes, the oxazole intermediate [4]
g (2.2 mmol) / 20 ml of THF was added dropwise, and the mixture was stirred for 2 hours, further stirred at 60 ° C. for 1 hour, water was added, the organic layer was extracted with ethyl acetate, dried over anhydrous sodium sulfate, and then silica gel column. And the oxazole compound No. 0.8 g of 10 (red crystals) was obtained (yield: 7).
5%).

[0103]

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Example 3 Compound no. Synthesis of 15 Oxime [5] (white crystal) was synthesized in the same manner as in Example 1.

[0105]

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In a 300 ml three-necked flask, 3.0 g (23.1 mmol) of phenylpropargylaldehyde, 5.2 g (34.6 mmol) of oxime [5], THF8
0 ml and dichloromethane 80 ml were added thereto, and 25.8 g of antiformin (12% aqueous solution) (4%
1.6 mmol) were added dropwise. After gradually heating and stirring at room temperature for 5 hours, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and purified by a silica gel column to obtain 3.5 g of an oxazole intermediate [6] (white crystals) (yield). Rate 5
5%).

[0107]

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In a 100 ml three-necked flask, 1.0 g (3.6 mmol) of the oxazole intermediate [6], 3.1 g (7.9 mmol) of a phosphonate compound and DM
50 g of F was added, and 1.0 g (8.7 mmol) of potassium t-butoxide was added thereto while stirring at 5 ° C. After gradually raising the temperature and stirring at room temperature for 3 hours, water was added, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and purified with a silica gel column. 2.0 g of 15 (yellow crystals) was obtained (yield 73%).

[0109]

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Example 4 Compound no. Synthesis of 20 Oxime [7] (white crystal) was synthesized in the same manner as in Example 1.

[0111]

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A 300 ml three-necked flask was charged with 3.0 g (12.8 mmol) of dibenzoylacetylene, 2.6 g (19.2 mmol) of oxime [7] and 150 ml of dichloromethane, and stirred at 0 ° C. with antiformin (12% aqueous solution). 14.3 g (23.0 mmol) were added dropwise and then 0.5 ml of triethylamine was added. After gradually raising the temperature and stirring at room temperature for 5 hours, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, purified on a silica gel column, and then an oxazole intermediate [8] (white crystals)
3.2 g was obtained (yield 69%).

[0113]

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In a 100 ml three-necked flask, 1.0 g (2.7 mmol) of the oxazole intermediate [8], 1.4 g (5.9 mmol) of the phosphonate compound and DM
After adding 40 ml of F, 0.73 g (6.5 mmol) of potassium t-butoxide was added at 5 ° C. while stirring. After gradually raising the temperature and stirring at room temperature for 3 hours, water was added, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and purified with a silica gel column. 1.0 g of 20 (white crystals) was obtained (67% yield).

[0115]

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Example 5 Compound no. Synthesis of 25 Oxime [9] (white crystal) was synthesized in the same manner as in Example 1.

[0117]

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In a 300 ml three-necked flask, 3.0 g (12.8 mmol) of dibenzoylacetylene, 3.8 g (19.2 mmol) of oxime [9], 80 ml of THF
And 80 ml of dichloromethane, and stirred at 0 ° C.
Antiformin (12% aqueous solution) 14.3 g (23.0
mmol) was added dropwise. After the temperature was gradually raised and stirred at room temperature for 5 hours, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and then purified on a silica gel column to obtain 4.1 g of an oxazole intermediate [10] (white crystals) (yield). Rate 75
%).

[0119]

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In a 200 ml three-necked flask, 1.0 g (2.3 mmol) of the oxazole intermediate [10] and 50 ml of acetic acid were added, and with stirring at room temperature, 0.23 g (4.6 mmol) of hydrazine monohydrate was added dropwise. After stirring at 90 ° C. for further 12 hours, the mixture was poured into water, the organic layer was extracted with ethyl acetate, dried over anhydrous sodium sulfate, and purified with a silica gel column. 2
0.65 g of 5 (yellow crystals) was obtained (66% yield).

[0121]

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Example 6 An element having the structure shown in FIG. 2 was prepared.

On a glass substrate as a substrate 1, indium tin oxide (ITO) as an anode 2 was
A film having a thickness of 20 nm was used as a transparent conductive support substrate. This was ultrasonically washed with acetone and isopropyl alcohol (IPA) sequentially, then washed with boiling IPA and dried. Further, the substrate subjected to UV / ozone cleaning was used as a transparent conductive support substrate.

A compound represented by the following structural formula was formed into a film having a thickness of 60 nm on a transparent conductive support substrate by a vacuum evaporation method to form a hole transport layer 5.

[0125]

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Further, Compound No. The oxazole compound represented by No. 1 was formed into a film having a thickness of 60 nm by a vacuum evaporation method to form an electron transport layer 6. The degree of vacuum during deposition is 1.0
× 10 ^-4 Pa, deposition rate 0.2 to 0.3 nm / sec
Under the following conditions.

Next, using a vapor deposition material composed of aluminum and lithium (lithium concentration 1 atomic%) as the cathode 4, a 150 nm thick film was formed on the organic layer by a vacuum vapor deposition method.
m of the metal layer film was formed. The degree of vacuum during vapor deposition is 1.0 × 1
The film was formed under the conditions of 0 ^-4 Pa and a film formation speed of 1.0 to 1.2 nm / sec.

When a DC voltage of 8 V was applied to the device thus obtained with the ITO electrode (anode 2) serving as a positive electrode and the Al—Li electrode (cathode 4) serving as a negative electrode, 8.3 mA / cm ^2.
And a blue light emission was observed at a luminance of 650 cd / m ² .

Further, the current density was increased to 7.0 under a nitrogen atmosphere.
When a voltage was applied for 100 hours while maintaining the current at mA / cm ² ,
470 cd after 100 hours from the initial luminance of 530 cd / m ²
/ M ² and the luminance degradation was small.

Examples 7 to 15 Exemplified Compound Nos. In place of Exemplified Compound No. 1, 4,6,9,12,15,1
An element was prepared in the same manner as in Example 6 except that the electron transport layer 6 was formed using 9, 23, 27, and 30, and the same evaluation was performed. Table 1 shows the results.

Comparative Examples 1 to 3 A device was prepared in the same manner as in Example 6, except that the electron transport layer 6 was formed using a compound represented by the following structural formula instead of 1, and the same evaluation was performed. Table 1 shows the results.

[0132]

Embedded image

[0133]

Embedded image

[0134]

Embedded image

[0135]

[Table 1]

Example 16 An element having the structure shown in FIG. 2 was prepared.

In the same manner as in Example 6, a hole transport layer 5 was formed on a transparent conductive support substrate. Further, the exemplified compound No.
An electron transport layer 6 was formed by depositing an oxazole compound represented by 10 and aluminum trisquinolinol (weight ratio 1:20) to a thickness of 60 nm by a vacuum evaporation method.
The degree of vacuum at the time of vapor deposition was 1.0 × 10 ⁻⁴ Pa, and the film formation rate was 0.
The film was formed under the conditions of 2 to 0.3 nm / sec.

Next, using a vapor deposition material composed of aluminum and lithium (lithium concentration 1 atomic%) as the cathode 4, a 150 nm thick film was formed on the organic layer by a vacuum vapor deposition method.
m of the metal layer film was formed. The degree of vacuum during vapor deposition is 1.0 × 1
The film was formed under the conditions of 0 ^-4 Pa and a film formation speed of 1.0 to 1.2 nm / sec.

When a DC voltage of 8 V was applied to the device thus obtained with an ITO electrode (anode 2) serving as a positive electrode and an Al-Li electrode (cathode 4) serving as a negative electrode, 9.0 mA / cm ² was applied.
A current flowed through the device at a current density of 1.9 cd / m ² , and light emission was observed at a luminance of 980 cd / m ² .

Further, the current density was increased to 7.0 under a nitrogen atmosphere.
When a voltage was applied for 100 hours while maintaining the current at mA / cm ² ,
Initial luminance of 790 cd / m ² to 700 cd after 100 hours
/ M ² and the luminance degradation was small.

[Examples 17 to 25] Exemplified Compound Nos. 1
0 in place of Exemplified Compound No. 2,5,8,13,1
A device was prepared in the same manner as in Example 16 except that the electron transport layer 6 was formed using 7, 18, 22, 26, and 28, and the same evaluation was performed. Table 2 shows the results.

[Comparative Examples 4 to 6] In place of Comparative Compound No. 10, An element was prepared in the same manner as in Example 16 except that the electron transport layer 6 was formed using 1, 2, and 3,
Similar evaluations were made. Table 2 shows the results.

[0143]

[Table 2]

Example 26 An element having the structure shown in FIG. 3 was produced.

As in Example 6, a hole transport layer 5 was formed on a transparent conductive support substrate. Next, the exemplified compound No. 2
The oxazole compound represented by the formula
The light emitting layer 3 was formed by forming a film with a thickness of 5 nm. Further, aluminum trisquinolinol is vacuum-deposited to 40 nm.
To form the electron transport layer 6. The degree of vacuum at the time of vapor deposition is 1.0 × 10 ⁻⁴ Pa, and the film formation rate is 0.2 to 0.3 n.
The film was formed under the conditions of m / sec.

Next, using a vapor deposition material composed of aluminum and lithium (lithium concentration 1 atomic%) as the cathode 4, a 150 nm thick film was formed on the organic layer by a vacuum vapor deposition method.
m of the metal layer film was formed. The degree of vacuum during vapor deposition is 1.0 × 1
The film was formed under the conditions of 0 ^-4 Pa and a film formation speed of 1.0 to 1.2 nm / sec.

When a DC voltage of 10 V was applied to the device thus obtained with the ITO electrode (anode 2) serving as a positive electrode and the Al—Li electrode (cathode 4) serving as a negative electrode, 12.0 mA / c was obtained.
current flows through the device at a current density of m ^2, 1450cd / m ²
A blue-green light emission was observed at a luminance of.

Further, the current density was set to 10.
When a voltage was applied for 100 hours while maintaining the current at 0 mA / cm ² , the initial luminance was changed from 1220 cd / m ² to 100 hours later.
The luminance degradation was small at 00 cd / m ² .

Examples 27 to 35 Exemplified Compound Nos. 2
0 in place of Exemplified Compound No. 3,7,11,14,1
A device was prepared in the same manner as in Example 26 except that the light emitting layer 3 was formed using 6, 21, 24, 25, and 29, and the same evaluation was performed. Table 3 shows the results.

[Comparative Examples 7 to 9] In place of Comparative Compound No. 20, Light-emitting layer 3 using 1, 2, and 3
A device was prepared in the same manner as in Example 26 except that was formed, and the same evaluation was performed. Table 3 shows the results.

[0151]

[Table 3]

Example 36 An element having the structure shown in FIG. 1 was produced.

On the transparent conductive support substrate used in Example 6, Exemplified Compound No. A solution obtained by dissolving 0.050 g of the oxazole compound represented by No. 10 and 1.00 g of poly-N-vinylcarbazole (weight average molecular weight = 63,000) in 80 ml of chloroform by a spin coating method (rotation speed = 2000 rpm) to form a 120 nm film. An organic layer (light-emitting layer 3) was formed by forming a thick film.

Next, using a vapor deposition material composed of aluminum and lithium (lithium concentration 1 atomic%) as the cathode 4, a 150 nm thick film was formed on the organic layer by a vacuum vapor deposition method.
m of the metal layer film was formed. The degree of vacuum during vapor deposition is 1.0 × 1
The film was formed under the conditions of 0 ^-4 Pa and a film formation speed of 1.0 to 1.2 nm / sec.

When a DC voltage of 10 V was applied to the device thus obtained with the ITO electrode (anode 2) serving as a positive electrode and the Al-Li electrode (cathode 4) serving as a negative electrode, 8.7 mA / cm
^At a current density of ² , current flowed through the device, and orange light emission was observed at a luminance of 540 cd / m ² .

[Comparative Example 10] In place of Comparative Compound No. 10, 2 was used to form a light-emitting layer 3, except that a light-emitting layer 3 was formed. In the same manner as in Example 36, when a DC voltage of 10 V was applied, a current flowed through the element at a current density of 8.4 mA / cm ² and 70 cd / cm ^2. Green light emission was observed at a luminance of m ² .

[0157]

As described above, the novel oxazole compounds represented by the general formulas [I] to [VII] of the present invention can be suitably used as an organic layer of an organic light emitting device.

The organic light-emitting devices using these oxazole compounds can emit light with high luminance at a low applied voltage and have excellent durability. In particular, the organic layer containing the oxazole compound of the present invention is excellent as an electron transporting layer and also excellent as a light emitting layer.

Further, the device can be prepared by using a vacuum evaporation method or a casting method, and a relatively inexpensive and large-area device can be easily prepared.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an organic light emitting device according to the present invention.

FIG. 2 is a cross-sectional view illustrating another example of the organic light emitting device according to the present invention.

FIG. 3 is a cross-sectional view illustrating another example of the organic light emitting device according to the present 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

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C09K 11/06 655 C09K 11/06 655 690 690 H05B 33/14 H05B 33/14 B 33/22 33/22 B (72) Inventor Andreessen Sven 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 3K007 AB02 AB06 AB11 AB18 CA01 CB01 DA01 DB03 EB00 4C056 AA01 AB01 AC01 AD01 AE03 4C063 AA01 AA03 BB01 BB03 CC51 CC92 DD04 DD08 DD12 DD51 EE10 4C072 AA01 BB02 CC03 CC11 DD10 EE02 FF07 FF08 GG01 HH02

Claims (15)

[Claims] 1. An oxazole compound represented by the following general formula [I]. Embedded image (Wherein X ₁ , X ₂ and X ₃ represent an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted vinyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group or X represents a substituted carbonyl group;
₁ , X ₂ and X ₃ may be the same or different. X ₂ and X ₃ may form a ring. ) 2. The oxazole compound according to claim 1, which is represented by the following general formula [II]. Embedded image (In the formula, R ₁ and R ₄ are substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, R ₁ and R ₄ are good .R ₂ and be different even in the same R ₃ represents a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group or a cyano group;
R ₂ and R ₃ may be the same or different. ) 3. The oxazole compound according to claim 1, which is represented by the following general formula [III]. Embedded image (Wherein R ₅ , R ₆ , R ₇ and R ₈ are a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group or a cyano group And R ₅ , R ₆ , R ₇ and R ₈ may be the same or different. R ₉ represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group.) 4. The oxazole compound according to claim 1, which is represented by the following general formula [IV]. Embedded image (In the formula, R ₁₀ , R ₁₁ and R ₁₂ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and R ₁₀ , R ₁₁ and R ₁₂ may be the same or different. R ₁₃ , R ₁₄ , R ₁₅ and R ₁₆ are each a hydrogen atom,
Represents an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group or a cyano group, even if R ₁₃ , R ₁₄ , R ₁₅ and R ₁₆ are the same It may be different. ) 5. The oxazole compound according to claim 1, which is represented by the following general formula [V]. Embedded image (In the formula, R ₁₇ , R ₁₈ and R ₁₉ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and R ₁₇ , R ₁₈ and R ₁₉ may be the same or different. Y is ＣC (R ₂₀ ) −C (R ₂₁ ) =, ＣC
(R ₂₂₎ represents a -N = or = N-N =. R _20, R ₂₁ and R ₂₂ represents a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, R _20, R
₂₁ and R ₂₂ may be the same or different. ) 6. The oxazole compound according to claim 2, which is represented by the following general formula [VI]. Embedded image (In the formula, R ₂₃ , R ₂₄ and R ₂₅ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and R ₂₃ , R ₂₄ and R ₂₅ may be the same or different. May be.) 7. A compound represented by the following general formula [VII]:
The oxazole compound according to claim 3, characterized in that: Embedded image(Where R₂₆, R₂₇, R₂₈, R₂₉And R₃₀Is the replacement
Or unsubstituted aryl group, substituted or unsubstituted hetero
A ring group;₂₆, R₂₇, R₂₈, R₂₉And R ₃₀Is the same
It may be the same or different. ) 8. An organic light-emitting element having at least a pair of electrodes comprising an anode and a cathode and one or more layers containing an organic compound sandwiched between the pair of electrodes, wherein at least one of the layers containing the organic compound is provided. Contains at least one oxazole compound represented by the following general formula [I]. Embedded image (Wherein X ₁ , X ₂ and X ₃ represent an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted vinyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group or X represents a substituted carbonyl group;
₁ , X ₂ and X ₃ may be the same or different. X ₂ and X ₃ may form a ring. ) 9. The organic light emitting device according to claim 8, wherein the oxazole compound is an oxazole compound represented by the following general formula [II]. Embedded image (In the formula, R ₁ and R ₄ are substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, R ₁ and R ₄ are good .R ₂ and be different even in the same R ₃ represents a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group or a cyano group;
R ₂ and R ₃ may be the same or different. ) 10. The organic light emitting device according to claim 8, wherein the oxazole compound is an oxazole compound represented by the following general formula [III]. Embedded image (Wherein R ₅ , R ₆ , R ₇ and R ₈ are a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group or a cyano group And R ₅ , R ₆ , R ₇ and R ₈ may be the same or different. R ₉ represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group.) 11. The organic light emitting device according to claim 8, wherein the oxazole compound is an oxazole compound represented by the following general formula [IV]. Embedded image (In the formula, R ₁₀ , R ₁₁ and R ₁₂ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and R ₁₀ , R ₁₁ and R ₁₂ may be the same or different. R ₁₃ , R ₁₄ , R ₁₅ and R ₁₆ are each a hydrogen atom,
Represents an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group or a cyano group, even if R ₁₃ , R ₁₄ , R ₁₅ and R ₁₆ are the same It may be different. ) 12. The organic light emitting device according to claim 8, wherein the oxazole compound is an oxazole compound represented by the following general formula [V]. Embedded image (In the formula, R ₁₇ , R ₁₈ and R ₁₉ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and R ₁₇ , R ₁₈ and R ₁₉ may be the same or different. Y is ＣC (R ₂₀ ) −C (R ₂₁ ) =, ＣC
(R ₂₂₎ represents a -N = or = N-N =. R _20, R ₂₁ and R ₂₂ represents a hydrogen atom, an alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, R _20, R
₂₁ and R ₂₂ may be the same or different. ) 13. The organic light emitting device according to claim 9, wherein the oxazole compound is an oxazole compound represented by the following general formula [VI]. Embedded image (In the formula, R ₂₃ , R ₂₄ and R ₂₅ represent a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and R ₂₃ , R ₂₄ and R ₂₅ may be the same or different. May be.) 14. The oxazole compound represented by the following general formula:
An oxazole compound represented by the formula [VII]
The organic light emitting device according to claim 10, wherein: Embedded image(Where R₂₆, R₂₇, R₂₈, R₂₉And R₃₀Is the replacement
Or unsubstituted aryl group, substituted or unsubstituted hetero
A ring group;₂₆, R₂₇, R₂₈, R₂₉And R ₃₀Is the same
It may be the same or different. ) 15. The organic compound according to claim 8, wherein at least one of the electron transport layer and the light emitting layer contains at least one of the oxazole compounds.
15. The organic light-emitting device according to any one of 14.