KR101511954B1 - New material for transporting electron and organic electroluminescent device using the same - Google Patents

Abstract

The present invention relates to a novel electron transport material and an organic light emitting device comprising the same. The present invention provides a novel electron transport material using the electron transport material according to the present invention, There is an advantage that the improved organic light emitting device can be manufactured.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a novel electron transport material and an organic light emitting device using the same. BACKGROUND ART < RTI ID = 0.0 &

The present invention relates to a novel electron transport material and an organic light emitting device using the same.

An organic light emitting device is a device that injects electric charge into an organic film formed between an electron injection electrode (cathode) and a hole injection electrode (anode) to form an electron and a hole. It is possible to form a device on a flexible transparent substrate such as a plastic substrate and to operate at a lower voltage (10 V or less) than a plasma display panel or an inorganic EL display, It is relatively small and has an advantage of excellent color.

The structure of a general organic electroluminescent device includes a substrate, a cathode, a hole injecting layer for receiving holes from the anode, a hole transporting layer for transporting holes, a light emitting layer for emitting light by combining holes and electrons, An electron transport layer, and a cathode. In some cases, a light emitting layer may be formed by doping a small amount of a fluorescent or phosphorescent dye to an electron transporting layer or a hole transporting layer without a separate light emitting layer. In the case of using a polymer, a hole transporting layer, a light emitting layer, and an electron transporting layer Can be performed simultaneously. The organic thin film layers between the two electrodes are formed by a vacuum deposition method, a spin coating method, an ink jet printing method, a roll coating method, or the like, and a separate electron injection layer may be inserted to efficiently inject electrons from the cathode.

Since the interface between the electrode and the organic material is stabilized, or the organic material has a large difference in moving speed between the hole and the electron, if a suitable hole transporting layer and electron transporting layer are used, holes and electrons can be effectively transferred to the light emitting layer. And the electron density are balanced so as to increase the luminous efficiency, the organic light emitting device is fabricated as a multilayer thin film structure.

On the other hand, typical examples of conventional electron transporting materials include aluminum complexes such as Alq3 (tris (8-hydroxyquinoline) aluminum (III)) and Bebq (bis (10-hydroxybenzo- [h] quinolinato) beryllium) and beryllium complexes. However, in the case of using these materials, there is a problem that the color purity is lowered due to the light emission by exciton diffusion when used for a blue light emitting device.

In addition, TPBI (see structure below) disclosed by Kodak in 1996 and disclosed in U.S. Patent No. 5,645,948 is known as a typical electron transport layer material having an imidazole group. Phenylbenzimidazole group and functions not only to block electrons from the luminescent layer but also to lower the stability of the device.

Particularly noteworthy in the conventional electron transporting material is that the driving voltage is merely slightly improved or the driving life of the device is remarkably lowered compared to the contents to be announced. In addition, variations in the lifetime of the devices and deterioration of thermal stability Side effects.

In addition, although the conventional organic light emitting element uses a fluorescent light emitting material, it gradually changes to adopt a phosphorescent light emitting material. Therefore, the electron transporting layer material, which is a common material, is also required to have suitable electron mobility, low driving voltage, and hole blocking property suitable for the phosphorescent material.

U.S. Patent No. 5,645,948

The present invention provides novel electron transport materials.

In addition, the present invention provides an organic light emitting device using the novel electron transport material and having improved light emission characteristics as well as enhanced driving voltage by inducing an increase in power efficiency, thereby improving power consumption.

The present invention relates to a novel electron transport material capable of greatly improving luminous efficiency, stability and device lifetime. The novel electron transport material of the present invention is represented by the following formula (1).

[Chemical Formula 1]

[In the above formula (1)

X ₁ to X ₅ are independently of each other N or CR and R is hydrogen, (C 1 -C 30) alkyl, (C 3 -C 30) cycloalkyl, (C 6 -C 30) aryl or (C 3 -C 30) heteroaryl;

L ₁ is a single bond, (C 6 -C 30) arylene or (C 2 -C 30) heteroarylene;

Z is S or O;

R ₁ is independently from each other (C ₁ -C 30) alkyl, (C 3 -C 30) cycloalkyl, (C 6 -C 30) aryl or (C 3 -C 30) heteroaryl;

Of said R alkyl, cycloalkyl, aryl, heteroaryl, arylene and heteroarylene, R ₁ alkyl, cycloalkyl, aryl and heteroaryl (C1-C30) alkyl, halo (C1-C30) alkyl of L ₁ (C1-C30) alkyl, (C6-C30) aryl, (C6-C30) aryl (C3-C30) aryl (C3-C30) heteroaryl, (C3-C30) heteroaryl substituted with (C1-C30) alkylsilyl, di (C1-C30) alkyl (C6-C30) arylsilyl, mono- or di Tri (C6-C30) arylsilyl, nitro, and hydroxy;

Wherein said heteroarylene and said heteroaryl comprise at least one heteroatom selected from B, N, O, S, P (= O), Si and P.

The novel electron transport material of the present invention has a heteroaryl as a central skeleton, especially a heteroaryl having pyrimidine as its central skeleton and a phenanthrene group as its central skeleton, The organic light emitting device having improved power consumption can be manufactured.

In addition, the novel electron transport materials of the present invention have phenanthrene groups in the central skeleton of heteroaryls and various substituents, especially thiazolopyridines, so that they have better luminescent properties and lifetime characteristics.

The substituents comprising the "alkyl", "alkoxy" and other "alkyl" moieties described in the present invention include both linear and branched forms, and "cycloalkyl" includes both single ring systems as well as substituted or unsubstituted adamantyl Or a plurality of cyclic hydrocarbons such as substituted or unsubstituted (C7-C30) bicycloalkyl. &Quot; Aryl " in the present invention means an organic radical derived from an aromatic hydrocarbon by one hydrogen elimination and is a single or fused ring containing 4 to 7, preferably 5 or 6 ring atoms, And includes a form in which a plurality of aryls are connected by a single bond. Specific examples include phenyl, naphthyl, biphenyl, terphenyl, anthryl, indenyl, fluorenyl, phenanthryl, triphenylenyl, pyrenyl, perylenyl, . Heteroaryl " as used in the present invention includes 1 to 4 hetero atoms selected from B, N, O, S, P (= O), Si and P as aromatic ring skeletal atoms and the remaining aromatic ring skeletal atoms are carbon An aryl group, a 5- to 6-membered monocyclic heteroaryl, and a polycyclic heteroaryl condensed with one or more benzene rings, and may be partially saturated. The heteroaryl in the present invention also includes a form in which one or more heteroaryl is connected to a single bond. The heteroaryl groups include divalent aryl groups in which the heteroatoms in the ring are oxidized or trisubstituted to form, for example, an N-oxide or a quaternary salt. Specific examples include furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl, triazolyl, Monocyclic heteroaryl such as tetrazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl and pyridazinyl, benzofuranyl, benzothiophenyl, isobenzofuranyl, benzoimidazolyl, benzothiazolyl, benzoiso Benzothiazolyl, benzothiazolyl, benzooxazolyl, isoindolyl, indolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, (Such as pyridyl N-oxide, quinolyl N-oxide), polycyclic heteroaryls such as benzyloxycarbonyl, benzyloxycarbonyl, benzyloxycarbonyl, benzyloxycarbonyl, Quaternary salts and the like.

The '(C 1 -C 30) alkyl' group described in the present invention is preferably (C 1 -C 20) alkyl, more preferably (C 1 -C 10) alkyl, and the ' Is (C6-C20) aryl. The '(C3-C30) heteroaryl' group is preferably (C3-C20) heteroaryl. The '(C3-C30) cycloalkyl' group is preferably (C3-C20) cycloalkyl, more preferably (C3-C10) cycloalkyl.

Specifically, R ₁ in Formula 1, which is a novel electron transport material of the present invention, may be selected from the following structural formulas.

[In the above formula,

R ₁₁ and R ₁₂ are each independently hydrogen, (C1-C30) alkyl, halo (C1-C30) alkyl, halogen, cyano, (C1-C30) alkoxy, (C6-C30) aryl, (C6-C30) (C1-C30) alkyl, (C1-C30) alkyl (C6-C30) aryl, (C3-C30) heteroaryl, nitro or hydroxy;

o is an integer from 1 to 5;

p or b are each independently an integer of 1 to 4;

q is an integer from 1 to 6;

r is an integer from 1 to 7;

and a is an integer of 1 to 3.]

Preferably, Formula 1, which is an electron transporting material of the present invention, may be represented by Formula 2 below.

(2)

[In the formula (2)

X ₃ to X ₅ are independently of each other N or CR and R is hydrogen, (C 1 -C 20) alkyl, (C 3 -C 30) cycloalkyl, (C 6 -C 30) aryl or (C 3 -C 30) heteroaryl;

L ₁ is a single bond, (C 6 -C 20) arylene or (C 2 -C 20) heteroarylene;

R ₁ is independently from each other (C ₁ -C 30) alkyl, (C 3 -C 30) cycloalkyl, (C 6 -C 30) aryl or (C 3 -C 30) heteroaryl;

Of said R alkyl, cycloalkyl, aryl, heteroaryl, arylene and heteroarylene, R ₁ alkyl, cycloalkyl, aryl and heteroaryl (C1-C30) alkyl, halo (C1-C30) alkyl of L ₁ (C1-C30) alkyl, (C6-C30) aryl, (C6-C30) aryl (C3-C30) aryl (C3-C30) heteroaryl, (C3-C30) heteroaryl substituted with (C1-C30) alkylsilyl, di (C1-C30) alkyl (C6-C30) arylsilyl, mono- or di Tri (C6-C30) arylsilyl, nitro, and hydroxy;

Wherein said heteroarylene and said heteroaryl comprise at least one heteroatom selected from B, N, O, S, P (= O), Si and P.

More preferably, the electron transporting material of the present invention may be represented by the following formulas (3) to (6).

(3)

[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

[In the above formulas 3 to 6,

X ₃ to X ₅ are independently of each other N or CR and R is hydrogen, (C 1 -C 20) alkyl, (C 3 -C 30) cycloalkyl, (C 6 -C 30) aryl or (C 3 -C 30) heteroaryl;

R ₁ is independently from each other (C ₁ -C 30) alkyl, (C 3 -C 30) cycloalkyl, (C 6 -C 30) aryl or (C 3 -C 30) heteroaryl;

Alkyl, cycloalkyl, aryl, heteroaryl, alkyl, cycloalkyl, aryl and heteroaryl of R ₁ of said R is halogen, cyano, (C6-C30) aryloxy, (C6-C30) aryl, (C6-C30 (C6-C30) aryl, (C3-C30) heteroaryl, (C3-C30) heteroaryl substituted with (C1- C30) aryl-substituted (C3-C30) heteroaryl nitro and hydroxy;

Wherein said heteroarylene and said heteroaryl comprise at least one heteroatom selected from B, N, O, S, P (= O), Si and P.

In the novel electron transport materials of the present invention represented by the above formulas 3 to 6, in terms of excellent luminescent properties and driving voltage enhancement,

Wherein X ₃ or X ₄ is N;

X < ₅ > is CH;

The R ₁ may be selected from the following structural formulas.

[In the above formula,

R ₁₁ and R ₁₂ are each independently hydrogen, (C1-C30) alkyl, halo (C1-C30) alkyl, halogen, cyano, (C1-C30) alkoxy, (C6-C30) aryl, (C6-C30) (C1-C30) alkyl, (C1-C30) alkyl (C6-C30) aryl, (C3-C30) heteroaryl, nitro or hydroxy;

o is an integer from 1 to 5;

p or b are each independently an integer of 1 to 4;

q is an integer from 1 to 6;

r is an integer from 1 to 7;

and a is an integer of 1 to 3.]

More specifically, the electron transport materials according to the present invention can be exemplified by the following compounds, but are not limited thereto.

The process for producing an electron transporting material according to an embodiment of the present invention is specifically illustrated in the following Reaction Scheme 1, but it is not limited thereto and may be produced through a conventional organic reaction.

[Reaction Scheme 1]

Wherein R ₁ , R, L ₁ , X ₁ to X ₅ and Z are the same as defined in Formula 1, and Ha is halogen.

In addition, the present invention provides an organic light emitting device, wherein the organic light emitting device according to the present invention includes a first electrode; A second electrode; And at least one organic material layer interposed between the first electrode and the second electrode, wherein the organic material layer includes an electron transporting layer including the electron transporting material of Formula 1. When the electron transporting material of Formula 1 according to the present invention is used in an electron transporting layer, the driving voltage is increased to increase the power efficiency, thereby improving power consumption.

In addition, the organic material layer may include at least one electron transport layer containing an electron transport material of Formula 1 and at least one light emitting layer comprising a fluorescent host-fluorescent dopant or a phosphorescent host-phosphorescent dopant. The fluorescent host, fluorescent dopant, phosphorescent host or phosphorescent dopant applied to the device is not particularly limited.

The electron transporting material of the present invention has an advantage of being able to manufacture an organic light emitting device in which power consumption is improved by inducing an increase in power efficiency by not only luminescing characteristics but also enhancing a driving voltage.

1 is a graph showing the efficiency (cd / A) - luminance (cd / m 2) of the organic light emitting device manufactured in Examples 1 to 3 and Comparative Example 1.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the present invention. However, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention. And does not intend to limit the scope of protection of the present invention.

 [Example 1] Preparation of Compound 5

compound  5-1 Manufacturing

(80.0 g, 0.311 mol), bis (pinacolato) diboron (90.36 g, 0.358 mol), 1,4-dioxane (1600 mL), 1,1'-bis (diphenylphosphino ) Ferrocene-Palladium (II) dichloride Dichloromethane complex (3.05 g, 0.004 mol) and potassium acetate (61.07 g, 0.622 mol) were mixed and refluxed with stirring. After 12 hours, the reaction mixture was cooled to room temperature, and a saturated aqueous solution of sodium chloride and ethyl acetate were added to extract the organic layer. The organic layer was dried over anhydrous magnesium sulfate, treated with activated charcoal, and filtered through celite. The obtained filtrate was concentrated under reduced pressure, and the obtained solid was suspended in hexane, filtered again, and washed with hexane to obtain solid compound 5-1 (71 g, 75%).

_{^{1 H-NMR (CDCl 3)}} δ [ppm]: 8.86 (m, 1H) 8.74-8.69 (m, 2H) 8.42 (S, 1H) 7.97 (d, 1H) 7.72-7.59 (m, 4H) 1.49 (s , 12H)

compound  5-2 Manufacturing

Compound 5-1 (60g, 0.197mol), 6-trichloro pyrimidine (38g, 0.207mol), THF ( 1200mL), Pd (PPh 3) 4 (2.28g, 0.002mol) and 2M K ₂ CO ₃ aqueous solution (450 mL) were mixed and refluxed with stirring for 18 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, saturated NaCl aqueous solution and ethyl acetate (EA) were added to extract the organic layer, dried over MgSO ₄ and concentrated under reduced pressure. Ethyl acetate was added to the resulting oil to precipitate a solid. The resulting solid was filtered and washed with ethyl acetate to give 34.6 g (54% yield) of compound 5-2.

_{^{1 H-NMR (CDCl 3)}} δ [ppm]: 8.82-8.80 (d, 1H), 8.75-8.73 (d, 1H) (d, 1H), 8.00 (s, 1H), 7.98 (s, 1H), 7.81-7.67 (m, 5 H)

compound  5-3 Manufacturing

(60.0 g, 0.195 mol), bis (pinacolato) diboron (57.04 g, 0.225 mol), 1,4-dioxane (1200 mL), 1,1'- (1.91 g, 0.002 mol) and potassium acetate (38.34 g, 0.391 mol) were mixed and refluxed with stirring. After 12 hours, the reaction mixture was cooled to room temperature, and a saturated aqueous solution of sodium chloride and ethyl acetate were added to extract the organic layer. The organic layer was dried over anhydrous magnesium sulfate, treated with activated charcoal, and filtered through celite. The resulting filtrate was concentrated under reduced pressure, and the resulting solid was suspended in hexane, filtered again, and washed with hexane to obtain solid compound 5-3 (54 g, 78%).

¹ H-NMR (CDCl 3)? 8.93-8.90 (m, 3H), 8.12-8.10 (q, 3H), 7.90-7.80

Preparation of compound 5-4

Compound (5-3) (40 g, 0.104 mol), compound 5-2 (24.99 g, 0.110 mol) and tetrahydrofuran (800 mL) are added. 1.21 g (0.001 mol) of tetrakis (triphenylphosphine) palladium (0) was added, 290 ml of 2M potassium carbonate aqueous solution was added, and the mixture was heated to reflux. After about 18 hours of reaction, the reaction was cooled to room temperature. The mixture was extracted with a saturated aqueous solution of sodium chloride and dichloromethane, dried over magnesium sulfate and concentrated under reduced pressure. The solid was separated by silica gel column (Hexane: M.C = 10: 1), concentrated and washed with hexane to obtain a pale yellow solid compound 5-4 (32.4 g, yield 60%).

_{^{1 H-NMR (CDCl 3)}} δ [ppm]: 9.34 (d, 1H), 8.95-8.94 (d, 1H), 8.86- 8.85 (d, 1H), 8.79-8.78 (d, 1H), 8.72-8.71 (d, 1H), 8.47-8.46 (d, 1H), 8.33-8.31 (q, 2H), 8.16-8.15 -7.76 (m, 8 H), 7.59 (s, 1 H)

compound  5-5 Manufacturing

5,4-b] pyridine (40 g, 0.137 mol), 4,4,5,5-tetramethyl-2- (4,4,5,5-tetra Dioxaborolan-2-yl) -1,3,2-dioxaborolane (40.12 g, 0.158 mol), 1,4-dioxane (800 mL), 1,1'- A mixture of bis (diphenylphosphino) ferrocene-palladium (II) dichloride dichloromethane complex (1.35 g, 0.0016 mol) and CH3CO2K (26.96 g, 0.275 mol) was mixed and refluxed for 12 hours and then cooled to room temperature. Saturated NaCl aqueous solution and ethyl acetate (EA) were added to the reaction mixture, and the organic layer was extracted, dried over MgSO ₄ , treated with activated charcoal, and filtered through celite. The resulting filtrate was concentrated under reduced pressure, and the obtained solid was suspended and stirred in nucleic acid, filtered and washed with nucleic acid to obtain Compound 5-5 (41.35 g, yield 89%).

¹ H-NMR (CDCl ₃ )? [Ppm]: 8.60-8.58 (d, IH), 8.50 (s, IH), 8.32-8.30 (d, IH), 8.25-8.22 (d, IH), 7.55 (t, IH), 7.48-7.44 (q, IH), 1.40

compound  5 Manufacturing

Compound 5-5 (20 g, 0.059 mol) and compound 5-4 (29.04 g, 0.056 mol) were placed in a 1000 mL-3-necked round bottom flask and 400 mL of tetrahydrofuran (THF) was added. Tetrakis (triphenylphosphine) palladium (0) (0.683 g, 0.0006 mol) was added, 145 ml of a 2M potassium carbonate aqueous solution was added, and the mixture was heated to reflux. After about 18 hours of reaction, the reaction was cooled to room temperature. The mixture was extracted with a saturated aqueous solution of sodium chloride and dichloromethane, dried over magnesium sulfate and concentrated under reduced pressure. The solid was separated by silica gel column (Hexane: M.C = 6: 1), concentrated and washed with hexane to obtain a white solid compound 5 (29.5 g, yield: 72%).

¹ H-NMR (CDCl ₃ )? [Ppm]: 9.47 (d, 1H), 9.00-8.98 (d, 1H), 8.90-8.89 (q, 1H) 8.87-8.83 (m, 2H), 8.54-8.52 (m, 2H), 8.47 (d, 1H), 8.35-8.33 (q, 2H), 8.28-8.26 7.79 (m, 11H), 7.71-7.67 (q, 2H), 7.34-7.31 (t, 1H)

[Example 2] Preparation of Compound 53

compound  53-1 Manufacturing

(43.22 g, 0.173 mol), 1,4-dioxane (1000 mL), 1,1'-bis (diphenyl (1.47 g, 0.002 mol) and potassium acetate (29.45 g, 0.3 mol) were mixed and refluxed with stirring. After 12 hours, the reaction mixture was cooled to room temperature, and a saturated aqueous solution of sodium chloride and ethyl acetate were added to extract the organic layer. The organic layer was dried over anhydrous magnesium sulfate, treated with activated charcoal, and filtered through celite. The obtained filtrate was concentrated under reduced pressure and the resulting solid was recrystallized with hexane to obtain solid compound 53-1 (46.79 g, 82%).

¹ H-NMR (CDCl ₃ )? [Ppm]: 8.27-8.26 (q, 2H), 7.84-7.82 (q, 2H), 7.66-7.64 (q, 2H), 7.49-7.38 (s, 12 H)

compound  53-2 Manufacturing

Pd (PPh ₃ ) ₄ (1.064 g, 0.0009 mol) and 2M K ₂ CO ₃ aqueous solution (250 mL) were added to a solution of Compound 53-1 (35 g, 0.092 mol), Compound 5-2 (22.04 g, 0.097 mol), THF (700 mL) ) Were mixed and refluxed with stirring for 18 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, saturated NaCl aqueous solution and ethyl acetate (EA) were added to extract the organic layer, dried over MgSO ₄ and concentrated under reduced pressure. Ethyl acetate was added to the resulting oil to precipitate a solid. The resulting solid was filtered and washed with ethyl acetate to give 30.3 g (61.49% yield) of compound 53-2.

¹ H-NMR (CDCl ₃ )? [Ppm]: 8.84-8.81 (m, 2H), 8.35 (d, 1H), 8.25-8.23 (q, 2H), 7.89-7.83 (q, 2H), 7.84-7.80 (m, 3H), 7.79-7.75 7.39 (m, 7H)

compound  53-3 Manufacturing

(22.0 g, 0.076 mol), bis (pinacolato) diboron (22.07 g, 0.087 mol), 1,4-dioxane (0.74 g, 0.0009 mol) and potassium acetate (14.83 g, 0.151 mol) were mixed and refluxed with stirring. The resulting mixture was stirred at room temperature for 2 hours. After 12 hours, the reaction mixture was cooled to room temperature, and a saturated aqueous solution of sodium chloride and ethyl acetate were added to extract the organic layer. The organic layer was dried over anhydrous magnesium sulfate, treated with activated charcoal, and filtered through celite. The obtained filtrate was concentrated under reduced pressure, and the resulting solid was suspended in hexane, filtered again, and washed with hexane to obtain solid compound 53-3 (19.93 g, 78%).

_{^{1 H-NMR (CDCl 3)}} δ [ppm]: 8.60-8.58 (d, 1H), 7.74-7.72 (d, 1H), 7.61-7.59 (d, 2H), 7.49-7.48 (d, 2H), 7.48 -7.44 (t, 1 H), 1.40 (s, 12 H)

compound  53 Manufacturing

Compound 53-3 (18 g, 0.053 mol), compound 53-2 (27.46 g, 0.051 mol) and tetrahydrofuran (800 mL) were added. Tetrakis (triphenylphosphine) palladium (0) (0.615 g, 0.0005 mol) was added, and 130 ml of a 2M potassium carbonate aqueous solution was added and the mixture was heated to reflux. After about 18 hours of reaction, the reaction was cooled to room temperature. The mixture was extracted with a saturated aqueous solution of sodium chloride and dichloromethane, dried over magnesium sulfate and concentrated under reduced pressure. The solid was separated by silica gel column (Hexane: M.C = 10: 1), concentrated and washed with hexane to obtain a white solid compound 53 (28.31 g, yield: 74%).

¹ H-NMR (CDCl ₃ )? [Ppm]: 8.81-8.77 (m, 2H), 8.54-8.52 (q, 1H), 8.42 (d, 1H), 8.32-8.30 (m, 1H), 7.94-7.92 (m, 4H), 7.90-7.88 (d, 2H), 7.83-7.80 1H), 7.34-7.31 (m, 2H), 7.50-7.66 (m, 2H), 7.56-7.53 1H)

[Example 3] Preparation of Compound 61

compound  61-1 Manufacturing

Benzo [d] imidazole (60 g, 0.172 mol), bis (pinacolato) diboron (50.17 g, 0.198 mol), 1,4-dioxane (1.684 g, 0.002 mol) and 1,1'-bis (diphenylphosphino) ferrocene-palladium (II) dichloride methane complex (1200 mL) and potassium acetate (33.723 g, 0.344 mol) were mixed and refluxed with stirring . After 12 hours, the reaction mixture was cooled to room temperature, and a saturated aqueous solution of sodium chloride and ethyl acetate were added to extract the organic layer. The organic layer was dried over anhydrous magnesium sulfate, treated with activated charcoal, and filtered through celite. The obtained filtrate was concentrated under reduced pressure, and the obtained solid was recrystallized with hexane to obtain solid compound 61-1 (52.43 g, 77%).

_{H-NMR (CDCl 3) δ} [ppm]: 7.92 (d, 1H), 7.76 (d, 2H), 7.59 (d, 2H), 7.56-7.45 (m, 3H), 7.41-7.29 (m, 4H) , 7.27 (s, 1 H), 1.35 (s, 12 H)

compound  61-2 Manufacturing

Compound 61-1 (45g, 0.114mol), compound 5-2 (27.19g, 0.119mol), THF (900mL), Pd (PPh 3) 4 (1.312g, 0.0012mol) and K ₂ CO ₃ aqueous solution of 2M (325mL ) Were mixed and refluxed with stirring for 18 hours. After the reaction was completed, the reaction mixture was cooled to room temperature, saturated aqueous NaCl solution and ethyl acetate (EA) were added to extract the organic layer, dried over MgSO4 and concentrated under reduced pressure. Ethyl acetate was added to the obtained oil to precipitate a solid. The resulting solid was filtered and washed with ethyl acetate to give compound 61-2 (36.82 g, yield 58%).

¹ H-NMR (CDCl ₃ )? [Ppm]: 8.85-8.81 (m, 2H), 8.32 (s, 1H), 8.18-8.13 (m, 4H), 7.89-7.87 (m, 7H), 7.72 (s, IH), 7.69-7.67 (q, IH), 7.64-7.56

compound  61-3 Manufacturing

(30 g, 0.103 mol), bis (pinacolato) diboron (29.99 g, 0.118 mol), 1,4 (4-fluoropyridin-3-yl) thiazolo [ (1.006 g, 0.0012 mol) and potassium acetate (20.155 g, 0.205 mol) were mixed together and refluxed in a reflux condenser Lt; / RTI > After 12 hours, the reaction mixture was cooled to room temperature, and a saturated aqueous solution of sodium chloride and ethyl acetate were added to extract the organic layer. The organic layer was dried over anhydrous magnesium sulfate, treated with activated charcoal, and filtered through celite. The obtained filtrate was concentrated under reduced pressure, and the obtained solid was suspended in hexane, filtered again, and washed with hexane to obtain solid compound 61-3 (23.34 g, 67%).

^{1 H-NMR (CDCl3) δ} [ppm]: 8.95 (s, 1H), 8.50 (s, 1H), 8.36-8.35 (d, 1H), 8.30 (s, 1H), 7.70-7.68 (d, 1H) , 7.24-7.21 (t, 1 H), 1.40 (s, 12 H)

compound  61 Manufacturing

Compound 61-3 (20 g, 0.059 mol), compound 61-2 (31.31 g, 0.056 mol) and tetrahydrofuran (THF) 400 mL were added. Tetrakis (triphenylphosphine) palladium (0) (0.681 g, 0.0006 mol) was added, 145 ml of a 2M potassium carbonate aqueous solution was added, and the mixture was heated to reflux. After about 18 hours of reaction, the reaction was cooled to room temperature. The mixture was extracted with a saturated aqueous solution of sodium chloride and dichloromethane, dried over magnesium sulfate and concentrated under reduced pressure. The solid was separated by silica gel column (Hexane: M.C = 4: 1), concentrated and washed with hexane to obtain a white solid compound 61 (25.6 g, yield: 59%).

¹ H-NMR (CDCl ₃ )? [Ppm]: 9.19-9.16 (q, 2H), 8.87-8.84 (m, 2H), 8.63-8.62 (t, 1H), 8.54-8.52 (d, IH), 8.30-8.29 (q, IH), 8.19-8.16 (m, 3H), 8.09 (s, IH), 7.92-7.83 (m, 8H), 7.80-7.75 -7.54 (m, 4H), 7.36-7.29 (m, 3H)

[Example 4] Fabrication of organic light emitting device using Compound 5 according to the present invention

A glass substrate of 25 mm x 25 mm x 0.7 mm, having an ITO (indium tin oxide) transparent electrode line with a thin film thickness of 150 nm, was ultrasonically cleaned for 10 minutes in distilled water containing detergent dissolved therein, Lt; / RTI > After the distilled water was cleaned, the substrate was ultrasonically cleaned by using a solvent of isopropyl alcohol, acetone, and methanol for 10 minutes sequentially and dried. Subsequently, the substrate was dry-cleaned with oxygen / argon plasma, and then a glass substrate having a transparent electrode line was mounted on a substrate holder of a vacuum evaporation apparatus. On the surface where the transparent electrode line was formed, a film thickness of 60 nm of IDE-406 (the following structure, I company) film was formed as a hole injecting layer. Next, H-1 (tetrakis-N-biphenyl-4-yl-benzidine, hereinafter referred to as H-1 film) with a film thickness of 30 nm was formed as a hole transporting layer on the film of IDE-406. Subsequently, BD-1 having the following structure was doped as a dopant on the H-1 film and ADN (9,10-di (naphthalene-2-yl) anthracene) as a luminescent host was deposited at a weight ratio of 16% As a light emitting layer.

Compound 5 of the present invention was deposited on the light-emitting layer to form an electron transport layer having a film thickness of 20 nm. Liq (lithium quinolate) was then deposited thereon to form an electron injection layer. Metal aluminum was deposited on the Liq film to form a metal cathode, thereby fabricating an organic light emitting device.

[Example 5] Fabrication of organic light emitting device using Compound 53 according to the present invention

An organic light emitting device was fabricated in the same manner as in Example 4, except that the compound 53 was used instead of the compound 5 as the electron transport layer material in Example 4.

[Example 6] Fabrication of organic light emitting device using compound 61 according to the present invention

An organic light emitting device was fabricated in the same manner as in Example 4, except that Compound 61 was used instead of Compound 5 as the electron transporting layer material in Example 4.

[Comparative Example 1] Production of organic light emitting device using compound ETM-1

An organic light emitting device was fabricated in the same manner as in Example 4, except that Compound ETM-1 having the following structure was used instead of Compound 5 as the electron transporting layer material in Example 4.

The electroluminescent characteristics and basic physical properties of the organic light emitting devices fabricated in Examples 4 to 6 and Comparative Example 1 are shown in Table 1 below. The organic light emitting devices manufactured in Examples 4 to 6 and Comparative Example 1 shown in FIG. (Cd / m < 2 >) relative to the efficiency (cd / A) of the device.

No. Voltage (V) Current density
(mA / cm ² ) efficiency
(cd / A) The color coordinates (x, y) Luminance
(cd / m 2) Example 1 6.70 18.77 5.87 0.13, 0.14 1278 Example 2 4.70 13.63 7.77 0.13, 0.15 1422 Example 3 5.80 18.01 6.12 0.13, 0.14 1046 Comparative Example 1 6.40 21.23 4.82 0.13, 0.14 1152

As shown in Table 1, it was confirmed that the luminescent characteristics of the electron transporting material of the present invention exhibited superior characteristics to those of the conventional materials.

That is, the electron transporting material of the present invention has heteroaryl as the central skeleton and various aryl or heteroaryl, especially phenanthrene and thiazolopyridine, in the central skeleton, and the organic light emitting device using the electron transporting material of the present invention has excellent luminescence characteristics In addition, by enhancing the driving voltage, it is possible to improve power efficiency by inducing an increase in power efficiency.

Claims (8)

An electron transporting material represented by the following formula (1).
[Chemical Formula 1]

[In the above formula (1)
X ₁ to X ₅ are, independently of each other, N or CR; R is hydrogen;
L ₁ is (C 6 -C 20) arylene or (C 2 -C 20) heteroarylene;
Z is S;
R < ₁ > is (C6-C30) aryl or (C3-C30) heteroaryl;
Wherein said aryl and heteroaryl of R < ₁ > are optionally substituted with one or more further selected from the group consisting of (C6-C30) aryl, (C3-C30) heteroaryl and (C6-C30) ≪ / RTI >
Wherein said heteroarylene and heteroaryl comprise at least one heteroatom selected from N and S. The method according to claim 1,
Wherein R < _{1 >} is selected from the following structural formulas.

[In the above formula,
R ₁₁ and R ₁₂ independently from each other are hydrogen, (C 6 -C 30) aryl or (C 3 -C 30) heteroaryl;
o is an integer from 1 to 5;
p or b are each independently an integer of 1 to 4;
q is an integer from 1 to 6;
r is an integer from 1 to 7;
and a is an integer of 1 to 3.] The method according to claim 1,
(1) is represented by the following formula (2).
(2)

[In the formula (2)
X ₃ to X ₅ independently of one another are N or CR and R is hydrogen;
L ₁ is (C 6 -C 20) arylene or (C 2 -C 20) heteroarylene;
R < ₁ > is (C6-C30) aryl or (C3-C30) heteroaryl;
Wherein said aryl and heteroaryl of R < ₁ > are optionally substituted with one or more further selected from the group consisting of (C6-C30) aryl, (C3-C30) heteroaryl and (C6-C30) ≪ / RTI >
Wherein said heteroarylene and heteroaryl comprise at least one heteroatom selected from N and S. The method according to claim 1,
(1) is represented by the following formulas (3) to (6).
(3)

[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

[In the above formulas 3 to 6,
X ₃ to X ₅ independently of one another are N or CR and R is hydrogen;
R < ₁ > is (C6-C30) aryl or (C3-C30) heteroaryl;
Wherein said aryl and heteroaryl of R < ₁ > are optionally substituted with one or more further selected from the group consisting of (C6-C30) aryl, (C3-C30) heteroaryl and (C6-C30) ≪ / RTI >
Wherein said heteroarylene and heteroaryl comprise at least one heteroatom selected from N and S. 5. The method of claim 4,
Wherein X ₃ or X ₄ is N;
X < ₅ > is CH;
Wherein R < _{1 >} is selected from the following structural formulas.

[In the above formula,
R ₁₁ and R ₁₂ independently from each other are hydrogen, (C 6 -C 30) aryl and (C 3 -C 30) heteroaryl;
o is an integer from 1 to 5;
p or b are each independently an integer of 1 to 4;
q is an integer from 1 to 6;
r is an integer from 1 to 7;
and a is an integer of 1 to 3.] The method according to claim 1,
Lt; RTI ID = 0.0 > of: < / RTI >

An organic light emitting device comprising an electron transport material according to any one of claims 1 to 6. 8. The method of claim 7,
The organic light emitting device includes a first electrode; A second electrode; And at least one organic material layer interposed between the first electrode and the second electrode, wherein the organic material layer includes an electron transporting layer containing the electron transporting material.

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