KR101025453B1 - Luminescent Compound for Organic Electroluminescent Device - Google Patents

Abstract

A luminescent compound which is used in an organic electroluminescent device by emitting blue in a solid and solution state as a compound containing a fluorene group according to the present invention and containing sulfur atoms at both ends of the fluorene group is represented by the following structural formula:

[Formula 1]

Wherein R ₁ and R ₂ are each independently an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, R ₃ is the same or different allyl group, heterocycle group or aliphatic hydrocarbon group, and R ₄ is An alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms having an alkyl group having 1 to 20 carbon atoms, or an allyl group having 6 to 20 carbon atoms having an alkoxy group having 1 to 20 carbon atoms, n Is an integer of 0-2, m is an integer of 1-3.

Organic EL device, bipolaron, hole transport layer, fluorene, sulfone, sulfide

Description

Luminescent Compound for Organic Electroluminescent Device             

1 is a graph showing UV-visible absorption spectra of PST, ST, and CNST compounds according to the present invention.

2 is a graph showing the photoluminescence spectra of PST, ST, and CNST compounds according to the present invention.

3 is a graph showing the photoluminescence spectrum according to the doping ratio in the PST / PVK doping system.

4 is a graph showing the photoluminescence spectrum according to the doping ratio in the ST / PVK doping system.

5 is a view schematically showing the structure of an organic light emitting diode (OLED).

6 is a graph showing the electroluminescence spectra of PST / PVK and ST / PVK.

7 is a graph showing the CIE color coordinates of PST / PVK and ST / PVK.

8 is a graph showing the luminance of the electroluminescent elements of PST / PVK and ST / PVK.

9 is a graph showing the luminous efficiency of PST / PVK and ST / PVK electroluminescent devices.                 

* Brief description of the major symbols in the drawings *

1: glass (substrate) 2: ITO (anode: transparent electrode)

3: hole transport layer (PEDOT: polyethylenedioxythiophene)

4: light emitting layer (PVK / Dye) 5: cathode (Mg / Ag)

6: Cathode protective layer (Ag) 7: Power supply

Field of invention

The present invention relates to an organic electroluminescent device. More specifically, the present invention relates to a novel light emitting compound used in an organic electroluminescent device by emitting blue light in a solid and solution state as a compound containing a fluorene group and containing sulfur atoms at both ends of the fluorene group.

Background of the Invention

Liquid crystal display (LCD), which is the most widely used at present, is a light-emitting display device that consumes little power and is light. However, the device driving system is complicated and characteristics such as response time and contrast are not satisfactory. Accordingly, researches on organic electroluminescence devices (OELDs, or 'organic EL devices'), which are recently attracting attention as flat panel displays, are being actively conducted. The organic electroluminescent device is a self-luminous device, and has various advantages such as excellent brightness, driving voltage, and response speed, and no viewing angle dependency, compared to a liquid crystal display.

In the organic EL device, holes are injected into a valence band (HOMO) of a hole injection layer at an anode and proceed to a light emitting layer through a hole transporting layer. At the same time, in the cathode, electrons move through the electron injection layer to the light emitting layer through the electron transporting layer, and combine with holes to form excitons. The exciton falls to the ground and emits light.

Using the principle of the organic EL device, in 1987, Eastmann Kodak developed an electroluminescent device using TPD as a hole transport layer and Alq ₃ as a light emitting layer (Appl. Phys. Lett. 51, 913). , 1987). Since then, research into electroluminescent devices using organic materials has been actively conducted.

Up to now, Eastman Kodak's Alq ₃ is widely used as a green light emitting material, and a blue light emitting material and a red light emitting material have been developed by many companies and research institutes, but there are still many improvements to be made.

Eastman Kodak Corp. has developed a hole (hole) transport material and a blue light emitting material using an anthracene-based derivative, which is disclosed in Korean Patent Publication Nos. 2000-48008 and 2000-48009.

In addition, Japanese Idemitsu Co., Ltd. has developed a blue light emitting compound using an anthracene-based and a bianthracene-based, which is disclosed in Korean Patent Laid-Open No. 2002-26864. In addition, Idemitsu Co., Ltd. has developed a blue light emitting compound in which a phenyl group of a side branch interferes with crystallization using an aromatic dimethylidine compound and has been patented in European Patent EP 0 388 768 B1.

A luminescent material incorporating fluorene into the main chain of the compound has also been developed and disclosed in Korean Patent Laid-Open Nos. 2001-79343, 2002-95210, 2001-31366, 2003-16169, and Korea Patent No. 280708, and Synthetic Metals (1997, 91, 209,) and J. Am. Chem. Soc. (2002, 124, 11571-1177). These compounds have a number of excellent properties with the introduction of fluorene. Fluorene groups as functional groups have excellent thermal and optical properties over the thermal decomposition temperature of 400 ° C., and have high photoluminescence quantum efficiencies of more than 50% in solution and solid state. It is also advantageous for blue light emission due to large bandgap energy (Macromolecular rapid commun. 22, 1365 (2001) / Chem. Mater. 13, 1984 (2001)).

In addition, blue OLED light emitting materials incorporating sulfone groups have been developed. The sulfone group improves the solubility of the compound, and is limited to excitons due to the intramolecular kink structure, and the HOMO-LUMO energy level is lowered, thereby providing high efficiency of light emission and high stability, which is suitable for blue organic electroluminescent device (OLE) materials. (Polym. Bull. 1999, 143, 13, Thin Solid Films 2001, 401, 111).

The present inventors have developed a novel luminescent compound used in an organic electroluminescent device which emits blue light in a solid and solution state as a compound containing a fluorene group and containing sulfur atoms at both ends of the fluorene group and having excellent luminous efficiency. It is early.

It is an object of the present invention to provide solids and solutions as compounds having a sulfide group, sulfoxide group, or sulfone group containing a fluorene group and containing sulfur atoms at both ends of the fluorene group. It is to provide a novel light emitting compound that emits blue light in a state.

Another object of the present invention is to provide a novel light emitting compound having excellent luminescence efficiency as a compound containing a fluorene group and having a sulfide group, a sulfoxide group, or a sulfone group containing sulfur atoms at both ends of the fluorene group.

It is still another object of the present invention to limit the excitons due to the good electron solubility, good solubility, color tuning and bending structure of the blue-expressing materials such as fluorene having a large band gap and high photoluminescence quantum efficiency in the chromophore. The present invention provides a novel light emitting compound that simultaneously introduces a sulfone group or a sulfide group to show blue electroluminescence and increase efficiency.

The above and other objects of the present invention can be achieved by the present invention described below.

Summary of the Invention

A luminescent compound which is used in an organic electroluminescent device by emitting blue in a solid and solution state as a compound containing a fluorene group according to the present invention and containing sulfur atoms at both ends of the fluorene group is represented by the following structural formula:

[Formula 1]

Wherein R ₁ and R ₂ are each independently an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, R ₃ is the same or different allyl group, heterocycle group, or aliphatic hydrocarbon group, and R ₄ is An alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms having an alkyl group having 1 to 20 carbon atoms, or an allyl group having 6 to 20 carbon atoms having an alkoxy group having 1 to 20 carbon atoms, n Is an integer of 0-2, m is an integer of 1-3.

Hereinafter, with reference to the accompanying drawings will be described in detail the contents of the present invention.

Detailed Description of the Invention

Compounds containing a fluorene group according to the present invention and containing sulfur atoms at both ends of the fluorene group can prevent the intermolecular packing intermolecular interaction to increase the luminous efficiency.

The present invention lowers the energy level of the highest occupied molecular orbital (HOMO) -lowest unoccupied molecular orbital (HOMO) by introducing sulfur atoms, in particular by including sulfone groups, sulfoxide or sulfide groups, thereby providing high efficiency of luminescence and high efficiency. Because of its stability, it is suitable as a blue organic electroluminescent (OLED) material.

The present invention is suitable as an organic electroluminescent (OLED) material that produces effective blue light emission by introducing fluorene groups having a large band gap.

A luminescent compound which is used in an organic electroluminescent device by emitting blue in a solid and solution state as a compound containing a fluorene group according to the present invention and containing sulfur atoms at both ends of the fluorene group is represented by the following structural formula:

[Formula 1]

Wherein R ₁ and R ₂ are each independently an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, R ₃ is the same or different allyl group, heterocycle group, or aliphatic hydrocarbon group, and R ₄ is An alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms having an alkyl group having 1 to 20 carbon atoms, or an allyl group having 6 to 20 carbon atoms having an alkoxy group having 1 to 20 carbon atoms, n Is an integer of 0-2, m is an integer of 1-3.

In particular, R ₃ is substituted or unsubstituted triphenylamine, substituted or unsubstituted naphthyldiphenylamine, substituted or unsubstituted oxadiazole, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms and alkoxy group having 1 to 20 carbon atoms. Unsubstituted anthracene, substituted or unsubstituted carbazole, substituted or unsubstituted fluorene, substituted or unsubstituted triphenylbenzene, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthalene, substituted or unsubstituted Diphenylbiphenylamine, substituted or unsubstituted 3,5-bis (trifluoro) biphenyl, and substituted or unsubstituted diphenyl-vinyl-phenyl.

More specifically, R ₃ may have a structure of the following Structural Formulas 2 to 5.

[Formula 2]

Wherein R ₂₁ , R ₂₂ and R ₂₃ are hydrogen or a substituent and p is an integer from 0 to 2.

[Formula 3]

Wherein R ₃₁ , R ₃₂ and R ₃₃ are hydrogen or a substituent, Ar ₃₁ is a divalent aryl group or heterocyclic group, and p is an integer from 0 to 2.

[Structure 4]

Wherein R ₄₁ , R ₄₂ , R ₄₃ and R ₄₄ are hydrogen or substituents and p is an integer from 0 to 2.

[Structure 5]

Wherein R ₅₁ , R ₅₂ and R ₅₃ are hydrogen or substituents and p is an integer from 0 to 2.

Allyl groups in the above formulas 1 to 5 are one ring or 2 to 4 rings having 6 to 30 carbons. For example, it is selected from rings such as phenyl, naphthyl, anthryl, phenanthryl and pyrenyl.

The heterocyclic group in the above Formula 1 to 5 is a saturated or unsaturated heterocyclic group having 3 to 10 atoms including a nitrogen atom, an oxygen atom, and a sulfur atom. For example, pyrolidine, pyrrole, imidazole, pyrazole, pyridine, pyrazine, pyridazine, triazole, triazole, Triazine, indole, indazole, purine, thiazoline, thiazole, thiadiazole, oxazoline, oxazole (oxazole), oxadiazole, quinoline, isoquinoline, isoquinoline, phthalazine, naphthyridine, quinoxaline, quinoxaline, quinazolin, and quinolin cinnoline, pteridine, acridinephenanthroline, acridinephenanthroline, phenzine, tetrazole, benzimidazole, benzoxazole, benzothiazole , Benzotriazole, tetrazaindene and thiophene, and the same or different water A.

Aliphatic hydrocarbon groups in the above formulas 1 to 5 are linear, branched, or cyclic alkyl groups. For example, methyl, ethyl, isopropyl, tert-butyl, n-octyl, n-decyl, n-hexa It is selected from materials such as decyl (n-hexadecyl), cyclopropyl (cyclopropyl), cyclopentyl (cyclophentyl), cyclohexyl (cyclohexyl).

Substituents in Formulas 1 to 5 are selected from the allyl, heterocyclic, and aliphatic hydrocarbon groups.

Representative examples of the compound according to the present invention represented by the formula 1 is as follows.

In Formula 1, when R ₁ and R ₂ are ethyl, R ₃ is -CH = CHPh-, n is 2, and R ₄ is methyl, the compound has the structure of Formula 1A. In the present specification, the compound of the following structural formula 1A is abbreviated as 'ST'.

[Formula 1A]

In Formula 1, R ₁ and R ₂ are ethyl, R ₃ is -PhCH = CHPh-, n is 2, and R ₄ is methyl, and has the structure of Formula 1B. In the present specification, the compound of formula 1B is abbreviated as 'PST'.

[Formula 1B]

In Formula 1, R ₁ and R ₂ are ethyl, R ₃ is -PhCH = CHCN-, n is 2, and R ₄ is methyl, and has the structure of Formula 1C. In the present specification, the compound of formula 1C is abbreviated as 'CNST'.

[Formula 1C]

In Formula 1, when R ₁ and R ₂ are ethyl, R ₃ is -Ph-, n is 0, and R ₄ is methyl, each has a structure of Formula 1D. In the present specification, the compound of the following structural formula 1D is abbreviated as 'sulfide compound'.

[Structure 1D]

In the present invention, since a substance capable of emitting blue light is introduced into the core and has a kink structure, it has a strong electron affinity, good solubility, good color tuning, and a sulfone that localizes excitons by the kink structure. By using the group has the effect of increasing the blue light emitting efficiency. It also shows excellent blue color purity in the doping system with the synthesized compound and PVK.

The preparation process of the compound according to the invention is as follows.

Preparation of 9,9-diethyl-9H-fluorene :

After replacing the reactor containing 9H-fluorene with nitrogen as shown in Scheme 1, the fluorene is dissolved in anhydrous tetrahydrofuran solution to make a low temperature -78 ℃. N-BuLi is slowly added dropwise through a syringe, followed by slowly dropwise addition of ethyl bromide. Stir at room temperature for 12 hours to purify the column.

Scheme 1

Preparation of 2,7-Dibromo-9,9-diethyl-9H-fluorene :

Distilled water, CuBr ₂ , and alumina were added to the 9,9-diethyl-9H-fluorene compound prepared above, followed by stirring, and then water was removed under reduced pressure. Then pretreated by drying in a vacuum oven at 90 ℃ for 12 hours. As shown in Scheme 2, pretreated 9,9-diethyl-9H-fluorene was added to carbon tetrachloride and pretreated CuBr ₂ / Alumina was added. Reflux with stirring at 90 ° C. for 5 hours. Purify by reprecipitation on n-Hexane.

Scheme 2

Preparation of 2,7-bis-bromomethyl-9,9-diethyl-9H-fluorene :

Paraformaldehyde and HBr were added to 9,9-diethyl-9H-fluorene as in Scheme 3 below, and the mixture was refluxed for 12 hours with mechanical stirring at 60 ° C. Purify by reprecipitation in ethyl acetate.

Scheme 3

Preparation of 7- (diethoxy-phosphorylmethyl) -9,9-diethyl-9H-fluoren-2-ylmethyl-phosphonic acid diethylester :

As shown in Scheme 4, 2,7-bis-bromomethyl-9,9-diethyl-9H-fluorene prepared above was dissolved in toluene together with triethyl phosphite. The mixture was refluxed at 130 ° C. for 12 hours and then purified by distillation.

Scheme 4

Preparation of Compound EF-B-al :

As shown in Scheme 5, 2,7-dibromo-9,9-diethyl-9H-fluorene prepared in Scheme 2 was converted to 4-formylphenylboronic acid and tetrakistriphenylphosphine palladium ( II) together in aqueous tetrahydrofuran / 2N sodium carbonate solution. The mixture was purified by reflux for 12 hours with stirring at 70 ° C.

Scheme 5

Preparation of Compound ST :

Potassium tertiary butoxide is added to a reactor with a hygroscopic tube and then dissolved in tetrahydrofuran. 7- (diethoxy-phosphorylmethyl) -9,9-diethyl-9H-fluoren-2-ylmethyl-phosphonic acid diethyl ester prepared in Scheme 4 together with 4-methysulfonylbenzaldehyde It is dissolved in tetrahydrofuran and then introduced into the reactor as in Scheme 6 below. After stirring for 30 minutes at room temperature, the column is purified by ethyl acetate: n-Hexane = 1: 1.

Scheme 6

Preparation of Compound PST :

As shown in Scheme 7, EF-B-al and MSOBP are dissolved in tetrahydrofuran, and then tertiary-butoxide is added to a reactor in which a hygroscopic tube in which tetrahydrofuran is dissolved is installed. Stirred at room temperature for 30 minutes and purified by column with ethyl acetate: n-Hexane = 1: 2.

Scheme 7

Preparation of Compound CNST :

As shown in Scheme 8, EF-B-al and phenylsulfonylacetonitrile were dissolved in benzene at room temperature in a reactor equipped with a absorption tube, and then 2-3 drops of piperidine and acetic acid were added dropwise thereto, and the mixture was heated at 80 ° C. for 1 hour. Reflux with stirring. Purify the column with ethyl acetate: n-Hexane = 1: 1.

Scheme 8

The present invention will be further illustrated by the following examples, which are merely illustrative of the present invention and are not intended to limit or limit the scope of the present invention.

Example

Preparation of 9,9-diethyl-9H-fluorene :

The reactor containing 5 g of 9H-fluorene was replaced with nitrogen, and the fluorene was dissolved in anhydrous tetrahydrofuran solution and then cooled to -78 ° C. 2.5 M n-BuLi 2 equivalents was slowly added dropwise by syringe, followed by 2 drops of ethyl bromide. Stirred at room temperature for 12 hours. Purified by column.

Preparation of 2,7-Dibromo-9,9-diethyl-9H-fluorene :

50 ml of distilled water, 5 g of CuBr2 and 10 g of alumina were added thereto, followed by stirring. Then, water was removed under reduced pressure. It was then pretreated by drying in a vacuum oven at 90 ° C. for 12 hours. 1 g of 9,9-diethyl-9H-fluorene was added to carbon tetrachloride and pretreated CuBr 2 / Alumina was added. It was refluxed with stirring at 90 ° C. for 5 hours. Purification by reprecipitation on n-Hexane.

Preparation of 2,7-bis-bromomethyl-9,9-diethyl-9H-fluorene :

5 g of 9,9-diethyl-9H-fluorene, 6.75 g of paraformaldehyde, and 69.1 g of HBr were added thereto, and the mixture was refluxed for 12 hours while being connected to a absorption tube and subjected to mechanical stirring at 60 ° C. Purification was carried out by reprecipitation on ethyl acetate.

Preparation of 7- (diethoxy-phosphorylmethyl) -9,9-diethyl-9H-fluoren-2-ylmethyl-phosphonic acid diethylester:

1 g of 2,7-bis-bromomethyl-9,9-diethyl-9H-fluorene and 1.26 mL of triethyl phosphite were dissolved in 10 mL of toluene. It was refluxed at 130 degreeC for 12 hours. Purification via distillation. Yield: 100%

Preparation of Compound EF-B-al :

1 g of 2,7-dibromo-9,9-diethyl-9H-fluorene, 0.8 g of 4-formylphenylboronic acid, and 0.036 g of tetrakistriphenylphosphine palladium (II) were added thereto. Tetrahydrofuran / 2N aqueous sodium carbonate solution = 40 mL / 20 mL was added and dissolved. It was refluxed for 12 hours with stirring at 70 degreeC. Purified by column. Yield: 53%

Preparation of Compound ST :

0.43 g of potassium tert-butoxide was added to a reactor having a hygroscopic tube, and then dissolved in tetrahydrofuran. 0.77 g of 7- (diethoxy-phosphorylmethyl) -9,9-diethyl-9H-fluoren-2-ylmethyl-phosphonic acid diethyl ester and 0.6 g of 4-methysulfonylbenzaldehyde are tetrahydrofuran It was dissolved in and then put into the reactor. Stirred at room temperature for 30 minutes. Ethyl acetate: n-Hexane = 1: 1 was purified by column.

Preparation of Compound PST :

0.3 g of EF-B-al and 0.47 g of MSOBP were dissolved in tetrahydrofuran, and 0.2 g of tertiary-butoxide was added to a reactor equipped with a hygroscopic tube dissolved in tetrahydrofuran. Stirred at room temperature for 30 minutes. The column was purified by ethyl acetate: n-Hexane = 1: 2. Yield 80%.

Preparation of Compound CNST :

0.2 g of EF-B-al and 0.185 g of phenylsulfonylacetonitrile were dissolved in benzene at room temperature in a reactor equipped with a absorption tube, and then 2-3 drops of piperidine and acetic acid were added dropwise thereto. It was refluxed with stirring at 80 ° C. for 1 hour. Ethyl acetate: n-Hexane = 1: 1 was purified by column.

Fabrication of Organic Light Emitting Device :

5, glass 1 (substrate), ITO (2) (anode: transparent electrode), hole transport layer (PEDOT: polyethylenedioxythiophene) (3), light emitting layer (PVK / Dye) (4), cathode (Mg) / Ag) (5), and an organic light emitting device (OLED) having a structure consisting of a cathode protective layer (Ag) (6).

Physical property measurement :

Physicochemical and optical tests were performed on the compound prepared above and the organic electroluminescent device. 1 is a graph showing UV-visible absorption spectra of PST, ST, and CNST compounds according to the present invention. 2 is a graph showing the photoluminescence spectra of PST, ST, and CNST compounds according to the present invention. 3 is a graph showing the photoluminescence spectrum according to the doping ratio in the PST / PVK doping system. 4 is a graph showing the photoluminescence spectrum according to the doping ratio in the ST / PVK doping system.

6 is a graph showing the electroluminescence spectra of PST / PVK and ST / PVK. 7 is a graph showing the CIE color coordinates of PST / PVK and ST / PVK. 8 is a graph showing the luminance of the electroluminescent elements of PST / PVK and ST / PVK. 9 is a graph showing the luminous efficiency of PST / PVK and ST / PVK electroluminescent devices.

The present invention is a compound containing a fluorene group and having a sulfone group or sulfide group containing sulfur atoms at both ends of the fluorene group, the blue light emission in the solid and solution state, the luminous efficiency is Introduces blue, such as fluorene, which has excellent band gap and high photoluminescence quantum efficiency, and sulfonated or sulfide group that has strong electron affinity and localizes excitons due to good solubility, color tuning and bending structure Thereby providing a novel electroluminescent compound that exhibits blue electroluminescence and increases efficiency.

Simple modifications and variations of the present invention can be readily used by those skilled in the art, and all such variations or modifications can be considered to be included within the scope of the present invention.

Claims (13)

A luminescent compound containing a fluorene group and containing sulfur atoms at both ends of the fluorene group and used in an organic electroluminescent device by emitting blue light in a solid and solution state: [Formula 1]

Wherein R ₁ and R ₂ are each independently an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, R ₃ is selected from the group consisting of the same or different allyl groups, heterocycle groups and aliphatic hydrocarbon groups, R ₄ is an allyl group having 6 to 20 carbon atoms having an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms having an alkyl group having 1 to 20 carbon atoms, and an alkoxy group having 1 to 20 carbon atoms. Selected from the group consisting of: n is an integer from 0 to 2 and m is an integer from 1 to 3. According to claim 1, wherein R ₃ is substituted or unsubstituted triphenylamine, substituted or unsubstituted naphthyldiphenylamine, substituted or unsubstituted oxadiazole, substituted or unsubstituted anthracene, substituted or unsubstituted Carbazole, substituted or unsubstituted fluorene, substituted or unsubstituted triphenylbenzene, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthalene, substituted or unsubstituted diphenylbiphenylamine, substituted or unsubstituted 3,5-bis (trifluoro) biphenyl, and substituted or unsubstituted diphenyl-vinyl-phenyl. The light emitting compound for use in an organic electroluminescent device. The light emitting compound of claim 1, wherein R ₃ is selected from the group consisting of functional groups of Formula 2, Formula 3, Formula 4 and Formula 5. [Formula 2]

In which R ₂₁ , R ₂₂ and R ₂₃ are hydrogen or substituents and p is an integer from 0 to 2; [Formula 3]

In which R ₃₁ , R ₃₂ and R ₃₃ are hydrogen or a substituent, Ar ₃₁ is a divalent aryl group or heterocyclic group, p is an integer from 0 to 2; [Structure 4]

In which R ₄₁ , R ₄₂ , R ₄₃ and R ₄₄ are hydrogen or substituents and p is an integer from 0 to 2; [Structure 5]

Wherein R ₅₁ , R ₅₂ and R ₅₃ are hydrogen or substituents and p is an integer from 0 to 2. The organic electroluminescent device of claim 3, wherein the allyl group is selected from the group consisting of phenyl, naphthyl, anthryl, phenanthryl and pyrenyl. Luminescent compounds used in the device. The method of claim 3, wherein the heterocyclic group is pyrolidine, pyrrole, imidazole, pyrazole, pyridine, pyrazine, pyridazine , Triazole, triazine, indole, indazole, purine, thiazoline, thiazole, thiadiazole, oxazoline (oxazoline), oxazole, oxadiazole, quinoline, quinoline, isoquinoline, phthalazine, naphthyridine, quinoxaline, quinoxaline, quinazolin quinazoline, cynoline, pteridine, acridinephenanthroline, phenzine, tetrazole, benzimidazole, benzoxazole, Selected from the group consisting of benzothiazole, benzotriazole, tetrazaindene and thiophene Light-compound used in the organic electroluminescent device, characterized in that. According to claim 3, wherein the aliphatic hydrocarbon group methyl (methyl), ethyl (ethyl), isopropyl (isopropyl), t-butyl (tert-butyl), n-octyl (n-octyl), n-decyl (n -decyl), n-hexadecyl, cyclopropyl (cyclopropyl), cyclopentyl (cyclophentyl) and cyclohexyl (cyclohexyl) is a light emitting compound used in the organic electroluminescent device, characterized in that selected from the group consisting of . 4. The light emitting compound of claim 3, wherein the substituent is selected from the group consisting of allyl, heterocyclic, and aliphatic hydrocarbon groups. The organic electroluminescent device according to claim 1, wherein R ₁ and R ₂ are ethyl, R ₃ is -CH = CHPh-, n is 2, and R ₄ is methyl, and is represented by the following structural formula 1A. Luminescent compounds used in: [Formula 1A]

The organic electroluminescent device according to claim 1, wherein R ₁ and R ₂ are ethyl, R ₃ is -PhCH = CHPh-, n is 2, and R ₄ is methyl, and is represented by the following structural formula 1B: Luminescent compounds used in: [Formula 1B]

The organic electroluminescent device according to claim 1, wherein each of R ₁ and R ₂ is ethyl, R ₃ is -PhCH = CHCN-, n is 2, and R ₄ is methyl, and is represented by the following Chemical Formula 1C. Luminescent compounds used in: [Formula 1C]

The organic electroluminescent device according to claim 1, wherein R ₁ and R ₂ are ethyl, R ₃ is -Ph-, n is 0, and R ₄ is methyl, and is represented by the following structural formula 1D. Emitting compounds: [Structure 1D]

An organic electroluminescent device comprising an organic film formed of the light emitting compound according to any one of claims 1 to 11 between a pair of electrodes comprising an anode and a cathode. An organic electroluminescent device comprising a device doped with a light emitting compound according to any one of claims 1 to 11 between a pair of electrodes comprising an anode and a cathode.

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