KR20020041987A - Bis-substituted quinoline-based red fluoroscent material, the preparation thereof, and organic electroluminescent device containing same - Google Patents

Abstract

PURPOSE: Provided are a bis-substituted quinoline red phosphor, which is excellent in stability and can express orange to red, and a preparation thereof and an organic electroluminescent element containing the bis-substituted quinoline red phosphor. CONSTITUTION: The bis-substituted quinoline red phosphor is represented by the formula (I) and produced by heat-reacting a compound represented by the formula (II) and a pyran derivative represented by the formula (III) in the molar ratio of about 1:2 in the presence of a base in an alcohol solvent, wherein A is C1-C4 alkylene, or C1-C4 alkyl or C1-C4 alkoxy substituted or unsubstituted aryl, aryloxy or heteroaryl, R1-R12 are independently hydrogen, C1-C4 alkyl, C1-C4 alkoxy, or C1-C4 alkyl or C1-C4 alkoxy substituted or unsubstituted aryl, aryloxy, or heteroaryl. And the organic electroluminescent element has an organic luminescent layer containing the red phosphor.

Description

B-SUBSTITUTED QUINOLINE-BASED RED FLUOROSCENT MATERIAL, THE PREPARATION THEREOF, AND ORGANIC ELECTROLUMINESCENT DEVICE CONTAINING SAME}

The present invention relates to a di-substituted quinoline derivative having a red light emission property, a method for preparing the same, and an organic electroluminescent device including the same.

Compounds well known as red fluorescent materials for organic electroluminescent devices to date are as follows: 4- (dicyanomethylene) -2-methyl-6- (4-dimethylaminostyryl) -4H-pyran (DCM) Nitrogen atoms have alkyl substituted groups such as methyl groups:

However, the conventional red light emitting material having an alkyl substituent is not only low in heat resistance, but also has a difficulty in emitting red color due to the light emitting color being in an orange region when used as a doping material for the light emitting layer of the organic light emitting device.

Accordingly, it is an object of the present invention to provide a novel red fluorescent substance and a method of manufacturing the same, and an organic electroluminescent device including the same, which are excellent in stability and can be expressed from an orange to a red region.

In order to achieve the above object, the present invention provides a di-substituted quinoline-based red fluorescent substance of the general formula (I):

Formula 1

Where

A is aryl optionally substituted by C _1-4 alkylene, or C _1-4 alkyl or C _1-4 alkoxy, aryl, aryloxy or heteroaryl,

R ₁ to R ₁₂ are each independently aryl, aryloxy or heteroaryl unsubstituted or substituted with hydrogen, C _1-4 alkyl, C _1-4 alkoxy, or C _1-4 alkyl or C _1-4 alkoxy, In this case, the hetero element in the heteroaryl may be nitrogen, sulfur or phosphorus.

The present invention also provides a method for preparing the compound of Formula (I) and an organic electroluminescent device comprising the compound in a light emitting layer.

Hereinafter, the present invention will be described in more detail.

The fluorescent material according to the present invention increases the molecular weight by about two times or more than the conventional red fluorescent material such as DCM to achieve a stable deposition rate during resistive heating.

Especially preferred in the compounds of the general formula (I) of the present invention are those wherein A is phenyl and R ₁ to R ₁₂ are each methyl, phenyl or benzyl.

The manufacturing process of the red fluorescent substance of the general formula (I) according to the present invention is shown in the following scheme.

Wherein A and R ₁ to R ₁₂ are each as defined above and R is as defined in R ₆ or R ₉ .

Specifically, the compound of formula (I) comprises about 1 compound of formula (II) and pyran derivative of formula (III) in the presence of a base such as piperidine in alcohol solvents such as methanol, ethanol and propanol. It can be synthesized by heating at a molar ratio of 2: 2, for example, by reacting at about 70 ° C. for about 1 to 5 hours.

The compounds of the general formula (II) used as starting materials are known in a known manner, for example in the Vilsmeier-Heck reaction at a temperature of 1 to 100 ℃ in the presence of POCl _{3 in an} organic solvent such as DMF. Can be synthesized, and the compound of formula (III) can be purchased commercially.

An organic light emitting device comprising the compound of formula (I) of the present invention comprises a hole transport layer, an compound-containing light emitting layer of formula (I) of the present invention and an electron transport layer (or a light emitting / electron transport layer) on an ITO-glass substrate. It can obtain by laminating | stacking in order according to a conventional method, then laminating | stacking a metal electrode for negative electrodes.

The novel fluorescent material according to the invention is preferably used as an orange or red light emitting doping material in the light emitting layer.

The hole transport layer, the light emitting layer and the electron transport layer of the organic electroluminescent device may be deposited by wet coating or vacuum deposition such as spin coating, doctor blading, roll printing or screen printing, and the metal electrode may be coated by vacuum deposition. .

The active material used to form the hole transport layer and the electron transport layer may be any known in the art, and examples of the metal electrode for the cathode may include aluminum, silver, calcium, magnesium, copper, and alloys thereof.

The novel red fluorescent substance according to the present invention is excellent in stability, and the organic electroluminescent device including the same in the light emitting layer may have a wide color of emission from orange to red region.

Through the following examples will be described the present invention in more detail. However, the scope of the present invention is not limited only to the following Examples.

Production Example

Compounds of formula (II-a) and formula (II-b) used as starting materials in the following examples were synthesized by the known Vilsmeier-Heck method, and the yield and NMR data thereof are as follows.

(II-a): yield 64%

¹ NMR (CDCl ₃ , 200 MHz) δ (ppm) 9.66 (2H, s), 7.49-7.50 (2H, d), 7.46 (2H, s), 6.60 (2H, s), 6.48-6.50 (2H, d) , 4.52 (6H, s), 3.46-3.50 (4H, t), 2.85-2.89 (4H, t), 2.02-2.06 (4H, m)

(II-b): Yield 76%

¹ NMR (CDCl ₃ , 200 MHz) δ (ppm) 9.87 (2H, s), 7.75-7.73 (2H, d), 7.57 (2H, s), 7.49-7.50 (2H, d), 7.46 (2H, s) , 7.39-7.41 (2H, d), 6.48-6.50 (2H, d), 4.56 (4H, s), 3.95 (2H, s), 3.48-3.52 (4H, t), 2.90-2.95 (4H, t) , 2.04-2.08 (4H, m)

Example 1

The compound of formula (I) of the present invention was prepared by the following scheme.

Specifically, 0.082 g (0.48 mmol) of 4-dicyanomethylene-2,6-dimethyl-4H-pyran in 10 ml of ethanol and 0.116 g (0.24 mmol) of the compound of formula (II-a) obtained in Preparation Example 1 were prepared. After addition, 0.045 g (0.52 mmol) of piperidine was added thereto and heated at 75 ° C. for 1-3 hours. The resulting red precipitate was filtered and washed with ethanol to give 0.1 g (53% yield) of the title compound.

Example 2

The compound of formula (I) of the present invention was prepared by the following scheme.

Specifically, 1.82 g (10.6 mmol) of 4-dicyanomethylene-2,6-dimethyl-4H-pyran in 10 ml of ethanol and 2.71 g (5.3 mmol) of the compound of formula (II-b) obtained in Preparation Example 2 were prepared. After addition, 1.26 g (14 mmol) of piperidine was added thereto and heated at 75 ° C. for 1-3 hours. The resulting red precipitate was filtered and washed with ethanol to give 2.756 g (63% yield) of the title compound.

The organometallic light emitting material of the present invention is excellent in stability and can be expressed from the orange to the red region, the organic light conductor (OPC), photorefractive thin film device, photodiode, solar It can be applied to the development of batteries and the like.

Claims (3)

Di-substituted quinoline red fluorescent substance of the general formula (I) Formula 1 Where A is aryl optionally substituted by C _1-4 alkylene, or C _1-4 alkyl or C _1-4 alkoxy, aryl, aryloxy or heteroaryl, R ₁ to R ₁₂ are each independently aryl, aryloxy or heteroaryl unsubstituted or substituted with hydrogen, C _1-4 alkyl, C _1-4 alkoxy, or C _1-4 alkyl or C _1-4 alkoxy. An organic electroluminescent device having an organic light emitting layer comprising a red fluorescent substance according to claim 1. The method of claim 2, The organic light emitting device, characterized in that the fluorescent material is used as an orange or red light emitting doping material.