CN1587268A - Anthracene compound and organic electroluminescent device comprising the anthracene compound - Google Patents

Abstract

The present invention relates to an anthracene compound having two silicon-based phenyl groups, which has photoluminescent properties and can be applied to organic electroluminescent devices. The compound has a chemical formula (I), wherein each _R1 and _R2 are independently hydrogen, a substituted or unsubstituted aromatic group having 6 to 20 carbon atoms, a substituted or unsubstituted heteroaromatic group having 2 to 5 carbon atoms, or a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, and each _R3 is independently a substituted or unsubstituted aromatic group having 6 to 20 carbon atoms or a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, wherein the substituent is a _C1-10 alkyl group, a _C1-10 alkoxy group, a phenyl group, or a halogen.

Description

Anthracene compound and organic electroluminescent device comprising the anthracene compound

technical field

The present invention relates to an anthracene compound, in particular to an anthracene compound with two silicon phenyl groups, which can be used as a luminescent material for an organic electroluminescent device.

Background technique

Organic electroluminescent device (organic electroluminescent device), also known as organic light-emitting diode (organic light-emitting diode; OLED), is a light-emitting diode (LED) with an organic layer as the active layer. Due to the advantages of low-voltage operation, high brightness, light weight, wide viewing angle, and high contrast value, organic electroluminescent devices have been gradually used in flat panel displays in recent years.

In general, an OLED includes a pair of electrodes, and a light emitting layer between the electrodes. Light emission is due to the following phenomenon: when an electric field is applied to both electrodes, the cathode emits electrons to the light-emitting layer, and the anode emits holes to the light-emitting layer. When electrons and holes combine in the light-emitting layer, the energy level shifts to the valence bond band, causing them to release energy and emit fluorescent light.

Anthracenes have been used as materials for hole transport layers and light emitting layers. For example, U.S. Patent No. 6,465,115 discloses an organic anthracene substance as a hole transport layer, which has the following chemical formula:

Its R ₁ , R ₂ , R ₃ , and R ₄ are each independently hydrogen, an alkyl group having 1 to 24 carbons, an aromatic group having 5 to 20 carbons or a substituted aromatic group, having 5 to 24 carbons heteroaryl or substituted heteroaryl, fluoro, chloro, bromo, or cyano.

In U.S. Patent No. 6,534,199 a luminescent anthracene compound is disclosed having a triarylamine moiety which may have the following chemical formula:

A luminescent aromatic silicon compound is disclosed in U.S. Patent No. 6,310,231, which may have the following chemical formula:

However, there is still demand for anthracene compounds with different structures in order to improve the luminous efficiency.

Contents of the invention

The present invention provides a kind of anthracene compound, has chemical formula (I)

Wherein, each R ₁ and R ₂ may be the same or different, independently hydrogen, a substituted or unsubstituted aromatic group with 6 to 20 carbon atoms, a substituted or unsubstituted aromatic group with 2 to 5 carbon atoms Atomic heteroaryl, or substituted or unsubstituted alkyl having 1 to 12 carbon atoms, each R ₃ may be the same or different, independently substituted or unsubstituted having 6 to 20 carbons Atomic aryl or substituted or unsubstituted alkyl having 1 to 12 carbon atoms, wherein the substituent is C _1-10 alkyl, C _1-10 alkoxy, phenyl, or halogen.

The present invention further provides an organic electroluminescent device, which comprises a pair of electrodes, and an organic luminescent medium layer between the pair of electrodes, wherein the organic luminescent medium layer includes the above-mentioned anthracene compound.

The present invention is characterized in that, in the anthracene compound according to the present invention, each of the 9 and 10 positions of the anthracene ring has a silylphenyl group as a substituent, and silicon may have a substituent.

In more detail, the anthracene compound according to the invention has the formula (I):

In chemical formula (I), R ₁ and R ₂ can be the same or different, can be hydrogen, substituted or unsubstituted aromatic groups with 6 to 20 carbon atoms, substituted or unsubstituted aryl groups with 2 to 5 carbon atoms atom, or a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms. Among them, hydrogen, a substituted or unsubstituted aromatic group with 6 to 10 carbon atoms, a substituted or unsubstituted heteroaryl group with 4 to 5 carbon atoms, or a substituted or unsubstituted heteroaryl group with 1 to 5 carbon atoms Alkyl group of 4 carbon atoms.

In chemical formula (I), each R ₃ may be the same or different, and independently is a substituted or unsubstituted aromatic group having 6 to 20 carbon atoms or a substituted or unsubstituted aromatic group having 1 to 12 carbon atoms alkyl. Among them, a substituted or unsubstituted aryl group having 6 to 10 carbon atoms or a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms is preferable.

For each of R ₁ , R ₂ , and R ₃ in the compound of formula (I), specific examples of substituted or unsubstituted aromatic groups having 6 to 20 carbon atoms include but are not limited to phenyl (phenyl), 2 -Methylphenyl, 3-methylphenyl, 4-methylphenyl, 4-ethylphenyl, biphenyl, 4-methylbiphenyl, 4-ethylbiphenyl, 4-cyclohexylbiphenyl, terphenyl, 3,5-dichlorophenyl, naphthyl, 5-methylnaphthyl, anthryl, and pyrenyl .

For each of R ₁ , R ₂ , and R ₃ in the compound of formula (I), specific examples of substituted or unsubstituted alkyl groups having 1 to 12 carbon atoms include, but are not limited to, methyl, ethyl, propyl butyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, 2-phenylisopropyl, trichloromethyl, and trifluoromethyl.

For each of R ₁ and R ₂ in the compound of formula (I), specific examples of substituted or unsubstituted heteroaryl groups having 2 to 5 carbon atoms include, but are not limited to, furanyl, thiophenyl ), pyrrolyl, pyranyl, thiopyranyl, pyridinyl, thiazolyl, imidazolyl, pyrimidinyl, and triazinyl (triazinyl).

The substituents of the aforementioned R ₁ , R ₂ , and R ₃ may be, for example, C _1-10 alkyl, C _1-10 alkoxy, phenyl, or halogen.

Specific examples of anthracene compounds according to the invention are listed below:

The anthracene compound of the present invention can emit light, especially blue light in several specific examples, or can be used as a blue light host material. This kind of luminescent material is novel and belongs to the one with higher luminous efficiency among blue light materials. For example, in a specific embodiment of the present invention, the luminous efficiency is as high as 3.2 cd/A, so it can be advantageously applied to organic electroluminescent devices. Furthermore, according to the anthracene compound of the present invention, it has two silicon-based phenyl groups. Due to the introduction of silicon-containing substituents, the structure has a silane molecular part. Therefore, in addition to being used as a light-emitting material, it can also be used as an organic electrical Electron transport materials or hole transport materials in luminescent devices.

Description of drawings

Fig. 1 is a graph showing the photoluminescence (PL) intensity of compound (1) and compound (2) at different wavelengths.

Detailed ways

The features and advantages of the present invention will be further described through several examples below. Synthesis of Preparation Example 1 Intermediate Product (2)

The synthetic route is as follows:

Intermediate Product (1) Intermediate Product (2)

Dissolve 1,3-dibromobenzene (5.7g, 24mmol) in 100mL of tetrahydrofuran (THF), and slowly add 9.2mL of n-butyllithium (n-BuLi, 21mmol, 2.3M) into the solution at -78°C middle. After 30 minutes, anthraquinone (2 g, 9.6 mmol) dissolved in 30 mL THF was added dropwise to the above mixture at -78 °C. The mixture was allowed to come to room temperature, then stirred for 24 hours. Cold water (100 mL) was added and the organic phase was separated. The aqueous phase was extracted with ethyl acetate. The organic phase was dried over MgSO ₄ and the solvent was removed by rotary evaporator to obtain the crude intermediate (1). KI (4.7 g, 29 mmol), sodium hypophosphite monohydrate (6.8 g, 58 mmol), and 50 mL of acetic acid were added to the crude product. The mixture was heated to reflux for 2 hours. After cooling, the white precipitate was collected and purified by column chromatography to give intermediate product (2) (4.5 g).

The synthesis of embodiment 1 compound (1)

The synthetic route is as follows:

Compound (1)

11.3 mL of n-butyllithium (27 mmol, 2.4 M) was slowly added to a solution of intermediate product (2) (6 g, 12.3 mmol) in 150 mL of anhydrous THF at -78°C. After 30 minutes, triphenylsilyl chloride (8 g, 27.1 mmol) dissolved in 20 mL of anhydrous THF was slowly added to the above mixture. The mixture was brought to room temperature, then stirred for 16 hours. Cold water (100 mL) was added, the precipitate was filtered off, and the filter cake was washed with 30 mL of ethanol and 30 mL of hexane to obtain a solid product. It was further purified by sublimation to obtain 4.0 g of compound (1).

Analysis data:

¹ H NMR (400MHz, CDCl ₃ ): δ7.3～7.5(m, 23H), 7.5～7.7(m, 15H), 7.7～7.84(m, 8H)

FAB-MS: m/e=847(M+)

The preparation of embodiment 2 compound (2)

The method is the same as in Example 1, but using 1,4-dibromobenzene to replace 1,3-dibromobenzene to obtain an intermediate product and further obtain compound (2).

Compound (2)

Figure 1 shows a graph of the photoluminescence (PL) intensity of compounds (1) and (2) at different wavelengths. It shows that the wavelength of the maximum intensity of both compounds (1) and (2) is about 420 nm, indicating blue light emission.

Embodiment 3 Preparation of organic electroluminescence device

The 750 nm-thick glass substrate having the ITO transparent electrode (anode) was cleaned by ultrasonic vibration using a neutral detergent, acetone, and ethanol. The substrate was blown dry with nitrogen, further cleaned with UV/ozone, and deposited under a pressure of 10 ⁻⁴ Pa. First, 2T-NATA (4,4′,4″-tris(N-(2-naphthyl)-N-phenylamino)-triphenylamine) was deposited on the ITO transparent electrode at a deposition rate of 0.1nm/sec. Thickness is 600nm, forms hole injecting layer.Then, with deposition rate 0.1nm/sec with NPB (N, N '-two (naphthalene-1-yl)-N, N '-diphenyl-benzidine) evaporation On the hole injection layer, the thickness is 30nm to form a hole transport layer.

Keep the vacuum, TBPe (2,5,8,11-tetra-tert-butylperylene) (2,5,8,11-Tetra-tert-butyl-perylene) and this The compound (1) of the specific embodiment of the invention was co-deposited on the hole transport layer with a thickness of 30 nm and a weight ratio of 2.5:100 to form a light emitting layer. After that, Alq3 (tris(8-quinolinolato)aluminum salt) was deposited on the resulting light-emitting layer at a deposition rate of 0.1 nm/sec to a thickness of 30 nm to form an electron injection/transport layer. Next, LiF and Al were deposited on the electron injection/transport layer at a deposition rate of 1 nm/sec to a thickness of 1 nm and 100 nm respectively to form an anode, and an organic electroluminescence device was obtained.

Using a direct current with a current density of 24mA/ ^cm2 to pass through the organic electroluminescent device obtained above, a blue luminescence of 770cd/ ^m2 and CIE (1931)=(0.15, 0.18) was measured, and the maximum luminous efficiency was 3.2cd/A.

Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the appended claims.

Claims (12)

1. An anthracene compound having the chemical formula (I) wherein each of R _{and R} is independently hydrogen, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 5 carbon atoms, or A substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, each _R3 is independently a substituted or unsubstituted aromatic group having 6 to 20 carbon atoms or a substituted or unsubstituted aryl group having 1 to 20 carbon atoms An alkyl group of 12 carbon atoms, wherein the substituent is a C _1-10 alkyl group, a C _1-10 alkoxy group, a phenyl group, or a halogen. 2. The anthracene compound as claimed in claim 1, wherein R ₃ is phenyl. 3. The anthracene compound as claimed in claim 1, wherein R ₃ is methyl. 4. The anthracene compound as claimed in claim 1, which has one of the following chemical formulas: 5. The anthracene compound according to claim 1, which is a luminescent material. 6. The anthracene compound as claimed in claim 1, which is a blue light matrix material. 7. An organic electroluminescent device comprising a pair of electrodes, and an organic luminescent medium layer between the pair of electrodes, wherein the organic luminescent medium layer comprises an anthracene compound, having the chemical formula (I)

wherein each of R _{and R} is independently hydrogen, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 5 carbon atoms, or A substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, each _R3 is independently a substituted or unsubstituted aromatic group having 6 to 20 carbon atoms or a substituted or unsubstituted aryl group having 1 to 20 carbon atoms An alkyl group of 12 carbon atoms, wherein the substituent is a C _1-10 alkyl group, a C _1-10 alkoxy group, a phenyl group, or a halogen. 8. The organic electroluminescence device as claimed in claim 7, wherein the R ₃ is phenyl. 9. The organic electroluminescent device as claimed in claim 7, wherein the R ₃ is methyl. 10. The organic electroluminescent device as claimed in claim 7, wherein the anthracene compound has one of the following chemical formulas:

11. The organic electroluminescence device as claimed in claim 7, wherein the organic light-emitting medium layer comprises a light-emitting layer, and the light-emitting layer comprises an anthracene compound having chemical formula (I). 12. The organic electroluminescent device as claimed in claim 7, wherein the organic light-emitting medium layer comprises a light-emitting layer, and the light-emitting layer comprises an anthracene compound having the chemical formula (I) as a blue light host material.

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