KR20170014439A

KR20170014439A - Organic electroluminescent compound, producing method of the same and organic electroluminescent divice including the same

Info

Publication number: KR20170014439A
Application number: KR1020150107814A
Authority: KR
Inventors: 윤승수; 김영석; 김좌진; 이현우; 김세현; 김동영; 정수진; 김영관; 이송은
Original assignee: 성균관대학교산학협력단
Priority date: 2015-07-30
Filing date: 2015-07-30
Publication date: 2017-02-08
Also published as: KR101774374B1

Abstract

The present invention relates to a novel organic light emitting compound, a method for producing the same, and an organic electroluminescent device including the same.

Description

TECHNICAL FIELD The present invention relates to an organic electroluminescent compound, an organic electroluminescent compound, a method for producing the same, and an organic electroluminescent device including the electroluminescent compound.

Display is an important means of visually expressing various information, and is rapidly developing in various fields. In particular, the LED industry is attracting attention as a next-generation technology of the future, and it is also leading the high-value-added derivative industry by combining various functions such as wavelength control, modulation, polarization, . Among them, OLED (Organic Light Emitting Diode) is a representative eco-friendly lighting that does not contain heavy metals such as lead and mercury compared to inorganic LED, and is becoming a light source to lead the future display market. In the case of such an OLED, a back light is not necessary, so that a lightweight thin type is possible, a response speed is high, and a contrast ratio and a viewing angle are excellent. In addition, a flexible substrate such as plastic can be used instead of a glass substrate to make it thinner and lighter without being broken, making it possible to develop a flexible display. Due to these characteristics, there is an unlimited possibility to be applied to a wearable device and a smart home.

In 1963, an organic electroluminescent device was first fabricated by using an anthracene single crystal by Pope et al. [M. Pope, HP Kallmamm and P. Magnae. J. Chem. Phys. 38, 2042 (1963)]. Subsequently, in 1987, a double layer thin film device using Alq ₃ and TPD as the light emitting layer and the charge transport layer, respectively, was reported by C. Tang and SA VanSlyke. Currently, the development of low-molecular OLED displays with improved efficiency and stability using a multi-layered EL device incorporating a charge injection layer and a transport layer is rapidly under development.

The realization of a full color display requires high stability, efficiency and color purity of the three primary colors of light, red, green and blue. In addition, as the display used for the organic electroluminescent device becomes large, high efficiency and long lifetime are demanded. However, blue light emitting materials exhibit shorter lifetime and lower EL characteristics than red and green. Because of the wide band gap of the blue light emitting material, charge injection and transmission are not easy due to mismatched between the charge transport layer and the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels It is not balanced. In order to solve this problem, studies have been actively conducted to change the light emitting core and the side groups to affect the HOMO and LUMO energy levels to facilitate charge injection (Korean Patent Laid-Open No. 10-2009-0111915). In addition, it is possible to increase the color purity and efficiency by preventing the formation of excimer and self-quenching by reducing the intermolecular interaction by fabricating a device using a host-dopant system. In order to further improve the characteristics of the organic electroluminescent device, development of a more stable and efficient material that can be used in the organic electroluminescent device is continuously required.

The present invention provides a novel organic light emitting compound, a method for producing the same, and an organic electroluminescent device including the same.

However, the problems to be solved by the present invention are not limited to the problems described above, and other problems not described can be clearly understood by those skilled in the art from the following description.

A first aspect of the invention provides an organic electroluminescent compound represented by Formula 1:

[Chemical Formula 1]

In Formula 1,

R ₁ and R ₂ are each independently a linear or branched C ₁ -C ₆ alkyl which may be substituted; A 5-membered unsaturated or aromatic ring which may be substituted, a 6-membered unsaturated or aromatic ring which may be substituted, a 5-membered unsaturated or aromatic heterocyclic ring which may be substituted and a 6-membered unsaturated or aromatic heterocyclic ring which may be substituted , Or a polycyclic ring fused with two or more rings selected from the above group,

R ₃ and R ₄ are each independently H; Or an arylamine group which may be substituted, a 5-membered unsaturated or aromatic ring which may be substituted, a 6-membered unsaturated or aromatic ring which may be substituted, a 5-membered unsaturated or aromatic heterocyclic ring which may be substituted, Is a polycyclic ring fused with at least one ring selected from the group consisting of a 6-membered unsaturated or aromatic heterocyclic ring or two or more rings selected from the group mentioned above,

Wherein the heterocycle includes at least one member selected from the group consisting of N, O and S,

The substitution is substituted by a linear or branched C ₁ -C ₆ alkyl, or a cyano group.

A second aspect of the present invention provides a process for preparing an organic luminescent compound according to the present invention which comprises reacting a compound represented by formula 2 with an arylamine or a heterocyclic compound in the presence of a palladium catalyst:

(2)

In Formula 2,

R ₅ and R ₆ are each independently H or halogen,

The third aspect of the present invention provides an organic electroluminescent device comprising the organic electroluminescent compound according to the present invention.

The organic luminescent compound of the present invention may be a dibenzo [ g , p ] chrysene derivative in which a bulky methyl group, a tert -butyl group, or a variety of aromatic and arylamine derivatives are introduced into one or both of Based organic luminescent compound. It is believed that by introducing bulky methyl, tert -butyl or various aromatic derivatives to both sides of a molecule to reduce intermolecular interactions and to form an excimer and self-quenching It is possible to increase the color purity and efficiency. Further, by introducing an electron-rich arylamine derivative, it is possible to control the emission wavelength of the device by changing the energy interval. This luminescent material can be used to control the luminescent characteristics of the device.

The organic electroluminescent compound of the present invention has high luminescence efficiency and high color purity and can contribute to the OLED industry such as flexible display and illumination by applying it to an organic electroluminescent device and an organic photonic device for solar power generation .

1 is a schematic view of an organic electroluminescent device according to an embodiment of the present invention.

Hereinafter, embodiments and examples of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains.

It should be understood, however, that the present invention may be embodied in many different forms and is not limited to the embodiments and examples described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout this specification, when a member is "on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as "including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise. The terms "about "," substantially ", etc. used to the extent that they are used throughout the specification are intended to be taken to mean the approximation of the manufacturing and material tolerances inherent in the stated sense, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure. The word " step (or step) "or" step "used to the extent that it is used throughout the specification does not mean" step for.

Throughout this specification, the term "combination thereof" included in the expression of the machine form means one or more combinations or combinations selected from the group consisting of the constituents described in the expression of the machine form, And the like.

Throughout this specification, the description of "A and / or B" means "A or B, or A and B".

Throughout this specification, the term "aromatic ring" refers to a C _6-30 aromatic hydrocarbon ring group such as phenyl, naphthyl, biphenyl, terphenyl, fluorene, phenanthrenyl, triphenylenyl, perylenyl Means an aromatic ring such as benzyl, benzyl, benzyl, benzyl, benzyl, benzyl, benzyl, benzyl, benzyl, benzyl, As the aromatic ring containing a hetero element, for example, pyrrolyl, pyrazinyl, pyridinyl, indolyl, isoindolyl, furyl, benzofuranyl, isobenzofuranyl, dibenzofuranyl, benzothiophenyl, di Thienyl, and pyridine rings, pyrazine rings, pyrimidine rings, pyridazine rings, pyrimidinyl rings, pyridazinyl rings, pyrimidinyl rings, pyridazinyl rings, A triazine ring, an indole ring, a quinoline ring , Acridine ring, pyrrolidine ring, dioxane ring, piperidine ring, morpholine ring, piperazine ring, carbazole ring, furan ring, thiophene ring, oxazole ring, oxadiazole ring, benzoxazine Means an aromatic heterocyclic group formed from a heterocyclic ring, a thiazole ring, a thiadiazole ring, a thiadiazole ring, a benzothiazole ring, a triazole ring, an imidazole ring, a benzimidazole ring, a pyran ring or a dibenzofuran ring.

Throughout this specification, the term "fused" means that, with respect to two or more rings, at least one or more adjacent atoms are included in both rings.

Throughout the specification, the term "alkyl" may be linear or branched, including saturated or unsaturated C ₁ -C ₆ alkyl, such as methyl, ethyl, propyl, butyl, pentyl, But is not limited to, all possible isomers.

Throughout the specification of the present application, the term "halogen" may include, but is not limited to, Group 17 elements of the periodic table, for example, F, Cl, Br,

[Chemical Formula 1]

In Formula 1,

The substitution may be, but is not limited to, substituted by linear or branched C ₁ -C ₆ alkyl, or cyano.

In one embodiment of the present invention, R ₁ and R ₂ may be the same as each other, but the present invention is not limited thereto. Wherein R ₁ and R ₂ are selected from the group consisting of methyl, dimethylethyl, phenyl, dimethylethylphenyl, naphthyl, fluorenyl, dibenzofuranyl, dibenzothiophenyl, furyl, thienyl, benzofuranyl, benzothiophenyl, Quinoline, and the like, but may not be limited thereto.

In one embodiment of the present invention, R ₃ and R ₄ may be the same as or different from each other, but may not be limited thereto. Wherein R ₃ and R _4, but may be selected from hydrogen, a diphenylamine group, and the group consisting of date of indole which may be substituted, may not be limited thereto. The diphenylamine group which may be substituted may be, for example, a cyano group, but may not be limited thereto.

In one embodiment herein, the organic light emitting compounds according to the present invention are based on dibenzo [ g , p ] chrysene derivatives with substituted aryl amine and bulky substituents as dopants. For example, an electron-rich arylamine group may be introduced to increase the mobility of holes and increase the HOMO energy level, thereby facilitating the injection of holes, but the present invention is not limited thereto.

In one embodiment of the present invention, the organic light emitting compound may include, but is not limited to, the following compounds:

A second aspect of the invention herein provides a process for preparing an organic luminescent compound according to the present invention which comprises reacting a compound represented by formula 2 with an arylamine or heterocyclic compound present in a palladium catalyst:

(2)

In Formula 2,

R ₅ and R ₆ are each independently H or halogen,

The substitution may be, but is not limited to, being substituted by a linear or branched C ₁ -C ₆ alkyl, or a cyano group.

In one embodiment of the invention, the arylamine may be, but is not limited to, an optionally substituted diphenylamine, such as diphenylamine or a cyano group-substituted diphenylamine. The polycyclic heterocyclic compound may include, but is not limited to, indole.

In one embodiment of the present invention, the organic light emitting compound may be doped in the light emitting layer of the organic electroluminescent device, but the present invention is not limited thereto.

In one embodiment of the invention, the organic light emitting device, for example, ITO (180 nm) / NPB (50 nm) / mADN: The organic electroluminescent compounds (20 nm, 3%) doped / Alq ₃ (30 nm) / Liq (1 nm) / Al (100 nm), but the present invention is not limited thereto. The organic electroluminescent device can be manufactured as follows: A transparent electrode ITO (indium-tin-oxide) thin film (sheet resistance 12 Ω / square) obtained from an organic EL glass is sequentially used with acetone, methanol, After ultrasonic cleaning, store in isopropyl alcohol for 20 minutes before use. The above ITO substrate was placed in a substrate folder of a vacuum deposition apparatus, NPB (4,4'-bis [N- (1-naphthyl) -N-phenylamino] -biphenyl) was added to a cell in a vacuum deposition apparatus, After evacuation until the degree of vacuum in the chamber reaches 5.0 x 10 < ^-7 > Torr, a current is applied to the cell to evaporate NPB to deposit a hole transporting layer of about 50 nm thickness on the ITO substrate. Thereafter, the organic light emitting compounds according to the present invention are doped into the mADN at a concentration of 3%, and then evaporated at a rate of 1.0 Å / sec to deposit a light emitting layer having a thickness of about 20 nm on the hole transporting layer. Then, Alq ₃ (tris (8-hydroxyquinoline) aluminum) and Liq (lithium quinolate) are sequentially evaporated to deposit an electron transport layer and an electron injection layer of about 30 nm and about 1 nm thick, respectively. Then, an Al cathode is deposited using another vacuum deposition equipment to manufacture an organic electroluminescent device.

The organic light emitting compounds according to aspects of the present invention may be applied to all of the first and second aspects of the present invention, but the present invention is not limited thereto.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited by these Examples.

[ Example ]

Example 1: 3 , 6-dimethyl-11- Diphenylamino Dibenzo [g, p] chrysene ( 1) of synthesis

1- (1): 3- Bromo -9,10- Of di (4-methylphenyl) phenanthrene synthesis

0.72 ml (2.5 eq, 6.83 mmol) of 1-bromo-4-methylbenzene was charged into a reaction vessel, dried under vacuum, and then filled with nitrogen gas. Then, 3.58 ml (2.1 eq, 5.73 mmol) of n-butyllithium (1.6 M) was slowly added dropwise at -78 deg. After stirring for 1 hour, 1.0 g (1 eq, 2.73 mmol) of 3-bromophenanthrene-9,10-dione was added to the reaction vessel. Then, the mixture was stirred at room temperature for 5 hours. After completion of the reaction, the organic layer was washed with distilled water and extracted with ethyl acetate. Dried over magnesium sulfate, filtered through celite and then chromatographed through column chromatography to yield 1.11 g of 3-bromo-9,10-dihydro-9,10-di (4-methylphenyl) phenanthrene- (40%). This was placed in a reaction vessel, vacuum dried, and then filled with nitrogen gas. Then, 60 ml of ethanoic acid was added, and the mixture was stirred under reflux at 120 ° C. After adding 0.9 g (5 eq, 14 mmol) of zinc powder, 0.3 ml (2.4 eq, 6.7 mmol) of hydrochloric acid and 1.7 ml (9.6 eq, 26.8 mmol) of ethanoic acid were added dropwise. After 30 minutes, 0.9 g (5 eq, 14 mmol) of zinc powder was added and 0.3 ml (2.4 eq, 6.7 mmol) of hydrochloric acid and 1.7 ml (9.6 eq, 26.8 mmol) of ethanoic acid were added dropwise. After completion of the reaction, the organic layer was washed with distilled water and extracted with dichloromethane. After drying over magnesium sulfate, the mixture was filtered through celite, and then 1.0 g (yield: 92%) of 3-bromo-9,10-di (4-methylphenyl) phenanthrene was obtained through column chromatography.

1- (2): 11- Bromo -3,6- Dimethyl dibenzo [ g , p ] Of Chrysene synthesis

1.1 g (1 eq, 3.07 mmol) of 3-bromo-9,10-di (4-methylphenyl) phenanthrene obtained in the above step 1- (1) was placed in a reaction vessel and vacuum dried and then purged with nitrogen gas. Then, 120 ml of dichloromethane as a solvent was dissolved in the reaction vessel. After lowering the temperature to 0 占 폚, 35 ml of methylene sulfonic acid and 1.4 g (2 eq, 6.14 mmol) of 2,3-dicloro-5,6-dicyano-1,4-benzoquinone were added thereto and stirred for 30 minutes. After completion of the reaction, the organic layer was washed with distilled water and extracted with dichloromethane. After drying over magnesium sulfate and filtration through celite, 0.61 g (yield: 55%) of 11-bromo-3,6-dimethyldibenzo [ g , p ] chrysene was obtained through column chromatography.

1- (3): 3,6-Dimethyl-11- Diphenylamino Dibenzo [g, p] chrysene ( 1) of synthesis

0.37 g (1 eq, 1.71 mmol) of 11-bromo-3,6-dimethyldibenzo [ g , p ] cresene and 0.27 g (2.2 eq, 1.6 mmol) of diphenylamine obtained in the above 1- (2) 0.053 g (0.08 eq, 0.058 mmol) of tris (dibenzylideneacetone) dipalladium (0) and 0.14 g (2 eq, 1.46 mmol) of sodium tert-butoxide were placed in a reaction vessel and vacuum dried and then purged with nitrogen gas. 25 ml of toluene was added to the above reaction vessel to dissolve the compounds. Then, 0.36 ml (1 eq, 1.71 mmol) of 50% tri- tert -butylphosphine was added and the mixture was refluxed at 120 ° C for 12 hours and stirred. After completion of the reaction, the reaction mixture was washed with distilled water and the organic layer was extracted with toluene. Dried over magnesium sulfate, filtered through celite and then subjected to column chromatography to obtain 0.23 g (yield: 45%) of the final compound 3,6-dimethyl-11-diphenylamino dibenzo [ g , p ] chrysene.

¹ H-NMR: (CDCl ₃ , 500 MHz,?); 2H), 7.35 (d, 2H), 7.05 (d, 2H), 7.65 (d, 2H) (m, 4 H), 2.65 (s, 6 H)

APCI-MS (m / z): 524 [M < + >] [

Example 2: 3 , 6-dimethyl-11,14- Bis ( Diphenylamino ) Dibenzo [ g , p ] Chrysene ( 2) of synthesis

2- (1): 3,6- Dibromo -9,10- Of di (4-methylphenyl) phenanthrene synthesis

Except that 3,6-dibromophenanthrene-9,10-dione was used instead of 3-bromophenanthrene-9,10-dione used in step 1- (1) of Example 1, (Yield: 89%) of 3,6-dibromo-9,10-di (4-methylphenyl) phenanthrene.

2- (2): 11,14- Dibromo -3,6-dimethyl Dibenzo [ g , p ] Of Chrysene synthesis

(3-bromo-9,10-di (4-methylphenyl) phenanthrene used in the step 1- (2) Dibromo-3,6-dimethyldibenzo [ g , p ] chrysene was synthesized in the same manner as in Example 1, except that 9,10-di (4-methylphenyl) : 60%).

2- (3): 3,6-Dimethyl-11,14- Bis ( Diphenylamino ) Dibenzo [ g , p ] Chrysene ( 2) of synthesis

Bromo-3,6-dimethyldibenzo [ g , p ] chrysene used in the 1- (3) step of Example 1 was replaced with 11,14-dibromo Mo-3,6-dimethyl-dibenzo [g, p], and is 3,6-dimethyl -11,14- bis synthesized by the same method except for using chrysene (diphenylamino) dibenzo [g, p ] Chrysene 0.38 g (Yield: 75%).

^{_{1 H-NMR: (CDCl 3}} , 500 MHz, δ): 8.50 (s, 2H), 8.45 (d, 2H), 7.90 (m, 2H), 7.405 (d, 2H), 7.31 (dd, 2H), (D, 8H), 7.15 (d, 8H), 7.04 (t, 6H), 2.64

APCI-MS (m / z): 691 [M < + >] [

Example 3: 3 , 6-di (1,1-dimethylethyl) -11-diphenylamino dibenzo [ g , p ] Synthesis of chrysene (3)

3- (1): 3- Bromo Synthesis of 9,10-di [4- (1,1-dimethylethyl) phenyl] phenanthrene

Except that 1-bromo-4- (1,1-dimethylethyl) benzene was used in place of 1-bromo-4-methylbenzene used in 1- (1) 1,27 g (yield: 55%) of 3-bromo-9,10-di [4- (1,1-dimethylethyl) phenyl] phenanthrene was obtained.

3- (2): 11- Bromo -3,6- Di (1,1-dimethylethyl) dibenzo [ g , p ] Of Chrysene synthesis

Bromo-9,10-di (4-methylphenyl) phenanthrene synthesized in the above step 3- (1) was used in place of 3-bromo- (1,1-dimethylethyl) phenyl] phenanthrene was used instead of di [4- (1,1-dimethylethyl) phenyl] phenanthrene, to obtain 11-bromo-3,6- g , p ] chrysene 0.69 g (Yield: 55%).

3- (3): 3,6-di (1,1-dimethylethyl) -11-diphenylamino dibenzo [ g , p ] Synthesis of chrysene (3)

Bromo-3,6-dimethyldibenzo [ g , p ] chrysene used in the step 1- (3) of Example 1 was replaced with 11-bromo- Di (1,1-dimethylethyl) dibenzo [ g , p ] chrysene was used in place of 3,6-di (1,1- 0.5 g (yield: 42%) of phenylamino dibenzo [ g , p ] chrysene was obtained.

^{_{1 H-NMR: (CDCl 3}} , 500 MHz, δ): 8.68 (s, 3H), 8.60 (d, 2H), 8.565 (d, 1H), 8.35 (d, 2H), 7.675 (td, 2H), 7.55 (m, 3H), 7.32 (t, 4H), 7.245 (d, 4H), 7.08 (t, 2H), 1.54 (s, 9H). 1.53 (s, 9 H)

APCI-MS (m / z): 608 [M < + >] [

Example 4: 3 , 6-di (1,1-dimethylethyl) -11,14-bis (diphenylamino) dibenzo [ g , p ] Synthesis of chrysene (4)

4- (1): 3,6- Dibromo -9,10- Di [4- (1,1-dimethylethyl) phenyl] phenanthrene synthesis

3,6-dibromophenanthrene-9,10-dione was used instead of 3-bromophenanthrene-9,10-dione used in step 1- (1) of Example 1, Dibromo-9,10-di [4 (1, 1-dimethylethyl) benzene was used in place of 1-bromo-4- - (1,1-dimethylethyl) phenyl] phenanthrene (yield: 42%).

4- (2): 11,14- Dibromo -3,6- Di (1,1-dimethylethyl) dibenzo [ g , p ] Of Chrysene synthesis

(3-bromo-9,10-di (4-methylphenyl) phenanthrene synthesized in the above step 4- (1) Dibromo-3,6-di (1,1-dimethylethyl) phenyl] phenanthrene was used in place of 9,10-di [4- (1,1- Dimethylethyl) dibenzo [ g , p ] chrysene (yield: 50%).

4- (3): 3,6-di (1,1-dimethylethyl) -11,14-bis (diphenylamino) dibenzo [ g , p ] Chrysene ( 4) of synthesis

The procedure of Example 1 was repeated except that 11,14-dibromo ( g , p ) synthesized in the above step 4- (2) was used instead of 11-bromo-3,6- Dibenzo [ g , p ] chrysene was used in place of 3,6-di (1,1-dimethylethyl) -11 , And 0.35 g (yield: 50%) of 14-bis (diphenylamino) dibenzo [ g , p ] chrysene were obtained.

^{_{1 H-NMR: (CDCl 3}} , 500 MHz, δ): 8.66 (s, 2H), 8.55 (m, 2H), 7.65 (d, 2H), 7.32 (m, 6H), 7.25 (m, 8H), (S, 9H), 1.525 (s, 9H), 7.16 (m, 8H)

APCI-MS (m / z): 775 [M < + >] [

Example 5: 3 , 6-di [4- (1,1-dimethylethyl) phenyl] -11-diphenylamino dibenzo [ g , p ] Chrysene ( 5) of synthesis

5- (1): 3- Bromo -9,10-di [4 '- (1,1-dimethylethyl) [1,1'-biphenyl] -4-yl] phenanthrene

Except that 1-bromo-4- (4 '- (1,1-dimethylethyl) phenylbenzene was used instead of 1-bromo-4-methylbenzene used in Example 1- (1) (Yield: 75%) of 3-bromo-9,10-di [4 '- (1,1- dimethylethyl) [1,1'- &Lt; / RTI >

5- (2): 11- Bromo -3,6- Di [4 '- (1,1-dimethylethyl) phenyl] dibenzo [ g , p ] Of Chrysene synthesis

Bromo-9,10-di (4-methylphenyl) phenanthrene synthesized in the step 5- (1) was used instead of 3- - di [4 '- (1,1-dimethylethyl) [1,1'-biphenyl] -4-yl] phenanthrene was used to synthesize 11- - di [4 '- (1,1-dimethylethyl) phenyl] dibenzo [ g , p ] cresene 0.63 g (Yield: 72%).

5- (3): 3,6-di [4- (1,1-dimethylethyl) phenyl] -11-diphenylamino dibenzo [ g , p ] Synthesis of chrysene (5)

Bromo-3,6-dimethyldibenzo [ g , p ] chrysene used in the step 1- (3) of Example 1 was replaced with 11- Di [4- (1,1-dimethylethyl) phenyl] dibenzo [ g , p ] 1-dimethylethyl) phenyl] -11-diphenylamino dibenzo [ g , p ] cresene 0.5 g (yield: 65%

^{_{1 H-NMR: (CDCl 3}} , 500 MHz, δ): 8.95 (d, 2H), 8.735 (dd, 2H), 8.71 (d, 1H), 8.60 (d, 1H), 8.37 (d, 2H), 2H), 7.87 (d, 2H), 7.79 (dd, 4H), 7.575 (dd, 2H), 7.385 (dd, 2H) (s, 9 H), 1.41 (s, 9 H)

APCI-MS (m / z): 760 [M < + >] [

Example 6: 3 , 6-di [4 '- (1,1-dimethylethyl) phenyl] -11,14-bis (diphenylamino) dibenzo [ g , p ] Synthesis of chrysene (6)

6- (1): 3,6- Dibromo -9,10-di [4 '- (1,1-dimethylethyl) [1,1'-biphenyl] -4-yl] phenanthrene

3,6-dibromophenanthrene-9,10-dione was used instead of 3-bromophenanthrene-9,10-dione used in step 1- (1) of Example 1, Except that 1-bromo-4- (4 '- (1,1-dimethylethyl) phenylbenzene was used in place of 3-bromo-4- Di [4 '- (1,1-dimethylethyl) [1,1'-biphenyl] -4-yl] phenanthrene was obtained in an amount of 0.6 g (yield: 66%).

6- (2): 11,14- Dibromo -3,6- Di [4 '- (1,1-dimethylethyl) phenyl] dibenzo [ g , p ] Of Chrysene synthesis

Except that 3,6-dibromo-9,10-di (4-methylphenyl) phenanthrene synthesized in the above step 6- (1) was used instead of 3- Di [4 '- (1,1-dimethylethyl) [1,1'-biphenyl] -4-yl] phenanthrene was used in place of 9,10- (Yield: 66%) of bromo-3,6-di [4 '- (1,1-dimethylethyl) phenyl] dibenzo [ g , p ]

6- (3): Synthesis of 3,6-di [4 '- (1,1-dimethylethyl) phenyl] -11,14- bis (diphenylamino) dibenzo [ g , p ] Chrysene ( 6) of synthesis

Bromo-3,6-dimethyldibenzo [ g , p ] chrysene used in the 1- (3) step of Example 1 was replaced with 11,14-dibromo Mo-3,6-di [4 '- (1,1-dimethylethyl) phenyl] dibenzo [g, p], and is synthesized by the same method except for using chrysene 3,6-di [4' - (1,1-dimethylethyl) phenyl] -11,14-bis (diphenylamino) dibenzo [ g , p ] chrysene was obtained in a yield of 45%

^{_{1 H-NMR: (CDCl 3}} , 500 MHz, δ): 8.94 (d, 2H), 8.75 (d, 2H), 8.56 (d, 2H), 7.85 (d, 2H), 7.78 (d, 4H). 2H), 7.27 (d, 2H), 7.17 (d, 10H), 7.06 (t, 6H), 1.41

APCI-MS (m / z): 927 [M +] <

Experimental Example 1: Measurement of organic electroluminescence characteristics

A glass substrate coated with an indium tin oxide (ITO) thin film was used for OLED manufacturing. The sheet resistance of the glass substrate was 12 Ω / square and the thickness was 180 nm. The ITO-coated glass was ultrasonically washed in an ultrasonic bath in the order of acetone, methyl alcohol, and distilled water, then left in isopropyl alcohol for 20 minutes and dried using a N ₂ gas gun. The substrate was treated with an O ₂ plasma in an Ar atmosphere. The above ITO substrate was placed in a substrate folder of a vacuum deposition apparatus, NPB (4,4'-bis [N- (1-naphthyl) -N-phenylamino] -biphenyl) was added to a cell in a vacuum deposition apparatus, After evacuation until the degree of vacuum in the chamber reached 5.0 x 10 < ^-7 > Torr, a current was applied to the cell to evaporate NPB to deposit a hole transporting layer about 50 nm thick on the ITO substrate. Then, the organic light emitting compounds 1, 2 and 4 prepared as in the above example and TPPD as a comparative example were added to mADN (2-methyl-9,10-bis (naphthalen-2-yl) anthracene) 3% concentration, and evaporated at a rate of 1.0 Å / sec to deposit a light emitting layer with a thickness of 20 nm on the hole transport layer. Then, Alq ₃ (tris (8-hydroxyquinoline) aluminum) and Liq (lithium quinolate) were sequentially evaporated to deposit an electron transporting layer and an electron injecting layer each having a thickness of about 30 nm and about 1 nm, respectively. All organic materials and metals is high ^vacuum was deposited under (5.0 × 10 ⁷ Torr). Then, an Al cathode was deposited by using other vacuum deposition equipment to manufacture an OLED. The OLED according to this experimental example was prepared in the following sequence: ITO (180 nm) / 4,4'-bis [N- (1-naphthyl) (20 nm, EML) / tris (ethylenediaminetetraacetic acid) (20 nm) doped with an organic luminescent compound (1, 2 and 4, and TPPD) 8-hydroxyquinoline) aluminum (Alq ₃ , ETL) (30 nm) / lithium quinolate (Liq) (1.0 nm) / Al (100 nm). The emission characteristics and the light emission (EL) spectrum of the OLED were measured using a Keithley 2400 source measurement unit and a CS1000A spectrophotometer, and the results are shown in Table 1.

It will be understood by those of ordinary skill in the art that the foregoing description of the embodiments is for illustrative purposes and that those skilled in the art can easily modify the invention without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention .

Claims

1. An organic electroluminescent compound represented by the following formula
[Chemical Formula 1]

In Formula 1,
R ₁ and R ₂ are each independently a linear or branched C ₁ -C ₆ alkyl which may be substituted; A 5-membered unsaturated or aromatic ring which may be substituted, a 6-membered unsaturated or aromatic ring which may be substituted, a 5-membered unsaturated or aromatic heterocyclic ring which may be substituted and a 6-membered unsaturated or aromatic heterocyclic ring which may be substituted , Or a polycyclic ring fused with two or more rings selected from the above group,
R ₃ and R ₄ are each independently H; Or an arylamine group which may be substituted, a 5-membered unsaturated or aromatic ring which may be substituted, a 6-membered unsaturated or aromatic ring which may be substituted, a 5-membered unsaturated or aromatic heterocyclic ring which may be substituted, Is a polycyclic ring fused with at least one ring selected from the group consisting of a 6-membered unsaturated or aromatic heterocyclic ring or two or more rings selected from the group mentioned above,
Wherein the heterocycle includes at least one member selected from the group consisting of N, O and S,
Said substitution being substituted by a linear or branched C ₁ -C ₆ alkyl, or cyano group.

The method according to claim 1,
Wherein R ₁ and R ₂ comprise the same with each other, the organic light emitting compound.

The method according to claim 1,
R ₃ and R ₄ are the same as each other.

The method according to claim 1,
Wherein R ₁ and R ₂ are selected from the group consisting of methyl, dimethylethyl, phenyl, dimethylethylphenyl, naphthyl, fluorenyl, dibenzofuranyl, dibenzothiophenyl, furyl, thienyl, benzofuranyl, benzothiophenyl, Quinoline. &Lt; / RTI >

The method according to claim 1,
Wherein R ₃ and R ₄ are selected from the group consisting of hydrogen, an optionally substituted diphenylamine group, and indolyl.

A process for preparing an organic luminescent compound according to claim 1, comprising reacting a compound represented by formula (2) with an arylamine or a heterocyclic compound in the presence of a palladium catalyst.
(2)

In Formula 2,
R ₁ and R ₂ are each independently a linear or branched C ₁ -C ₆ alkyl which may be substituted; A 5-membered unsaturated or aromatic ring which may be substituted, a 6-membered unsaturated or aromatic ring which may be substituted, a 5-membered unsaturated or aromatic heterocyclic ring which may be substituted and a 6-membered unsaturated or aromatic heterocyclic ring which may be substituted , Or a polycyclic ring fused with two or more rings selected from the above group,
R ₅ and R ₆ are each independently H or halogen,
Wherein the heterocycle includes at least one member selected from the group consisting of N, O and S,
Said substitution being substituted by a linear or branched C ₁ -C ₆ alkyl, or cyano group.

The method according to claim 6,
Wherein the polycyclic heterocyclic compound comprises an indole.

An organic electroluminescent device comprising the organic electroluminescent compound according to any one of claims 1 to 5.

9. The method of claim 8,
Wherein the organic light emitting compound is doped in the light emitting layer of the organic electroluminescent device.