CN104629748A - Blue-ray organic electroluminescent material, as well as preparation method and organic electroluminescent device thereof - Google Patents

Abstract

The invention belongs to the field of organic electroluminescent materials, and discloses a blue-ray organic electroluminescent material, as well as a preparation method and an organic electroluminescent device thereof. The material has a structural formula as shown in the specification. In the blue-ray organic electroluminescent material, imidazole is a relatively good electron transmission unit and has good thermal stability, anthracene and phenanthrene have relatively high fluorescence quantum yield, and the luminescence efficiency of the organic electroluminescent device can be improved by using the material as a luminescent layer material.

Description

Blue-ray organic electroluminescent material and preparation method thereof and organic electroluminescence device

Technical field

The present invention relates to field of organic electroluminescent materials, particularly relate to a kind of blue-ray organic electroluminescent material and preparation method thereof.The invention still further relates to a kind of this blue-ray organic electroluminescent material that adopts as the organic electroluminescence device of luminescent layer material of main part.

Background technology

Organic electroluminescent has the features such as low-voltage direct-current drives, brightness is high, diopter is wide, be considered to one of most promising flat panel display technology of future generation (C.W.Tang and S.A.Vanslyke.Appl.Phys.Lett., 1987,51 (12): 913-915).Organic molecule electroluminescent device is made up of more than two layers organic molecular films mostly, and they have electronics and hole transport performance respectively.And organic polymer electroluminescent device only needs individual layer organic film (J.H.Burroughes, D.D.C.Bradley, A.R.Brown, R.N.Marks, K.Mackay, R.H.Friend, P.L.Burns and A.B.Holms.Nature, 1990,347:539-541), thus its preparation technology is more convenient.The minimizing at molecular layer part interface, favourable to the stability of device.Organic molecule electroluminescent device needs two-layer with upper film, and be the restriction of the carrier transmission characteristics due to the organic molecule used, or they are based on transmission electronic, or based on transporting holes.The performance of organic molecule depends on its structure, its carrier transmission characteristics is relevant with the conjugated system of molecule, polyaromatic conjugated system often has electronic transmission performance, and triarylamine quasi-molecule has cavity transmission ability, although can molecular designing be passed through at present, obtain luminescent organic molecule material that is of a great variety, different properties, but have that such as price is high, preparation is complicated, second-order transition temperature (T _g) low, the not high deficiency of carrier transmission performance.

Summary of the invention

Problem to be solved by this invention is to provide a kind of glass transition temp and the higher blue-ray organic electroluminescent material of carrier transmission performance.

For achieving the above object, blue-ray organic electroluminescent material provided by the invention, its structure is such as formula as follows:

i.e. 2,2 '-(4,4 '-(2-tert-butyl anthracene-9,10-bis-base) two (4,1-penylenes)) two (1-phenyl-1H-phenanthro-[9,10-d] imidazoles).

Another object of the present invention is to provide the preparation method of the blue-ray organic electroluminescent material that a kind of synthetic route is simple, material is cheap and easy to get, described preparation method comprises the steps:

The compd A providing following structural formula to represent respectively and B,

Under oxygen-free environment, compd A and B are added in the organic solvent containing catalyzer and alkaline solution and dissolve, compd A and B mol ratio are 1:2 ~ 2.4, the mixing solutions obtained after dissolving carries out Suzuki coupling reaction 12 ~ 48 hours at 70 ~ 130 DEG C, stopped reaction cool to room temperature, separating-purifying reaction solution, obtains blue-ray organic electroluminescent material described in following structural formula:

Wherein, described catalyzer is bis-triphenylphosphipalladium palladium dichloride or tetra-triphenylphosphine palladium; Or,

Described catalyzer is the mixture of organic palladium and organophosphorus ligand, and the mol ratio of described organic palladium and organophosphorus ligand is 1:4 ~ 8; Preferably, described organic palladium is palladium or three or two argon benzyl acetone two palladiums, and described organophosphorus ligand is three (o-methyl-phenyl-) phosphines or 2-dicyclohexyl phosphine-2 ', 6 '-dimethoxy-biphenyl; More preferably, described mixture is the mixture of palladium and three (o-methyl-phenyl-) phosphine, or described mixture is three or two argon benzyl acetone two palladiums and 2-dicyclohexyl phosphine-2 ', the mixture of 6 '-dimethoxy-biphenyl.

The mol ratio of described catalyzer and described compd A is 1:20 ~ 1:100.

In described preparation method, described alkaline solution is selected from least one in sodium carbonate solution, solution of potassium carbonate and sodium hydrogen carbonate solution; In described alkaline solution, the mol ratio of alkali solute and described compd A is 20:1.

In a preferred embodiment, organic solvent is selected from least one in toluene, DMF, tetrahydrofuran (THF).

In a preferred embodiment, the temperature of reaction of Suzuki coupling reaction is 90 ~ 120 DEG C, and the reaction times is 24 ~ 36 hours.

In a preferred embodiment, described separating-purifying reaction solution comprises:

After Suzuki coupling reaction stops, with dichloromethane extraction reaction solution repeatedly and merge organic phase, after this organic phase is spin-dried for after anhydrous magnesium sulfate drying, obtain crude product, this crude product adopts volume ratio to be that sherwood oil and the ethyl acetate of 10:1 mixes leacheate and be separated through silica gel column chromatography and obtain crystalline substance, this crystalline substance, under vacuo after 50 DEG C of dry 24h, obtains described blue-ray organic electroluminescent material.

In described preparation method, oxygen-free environment is made up of at least one gas in argon gas, nitrogen.

Above-mentioned preparation method's principle is simple, easy and simple to handle, low for equipment requirements, can wide popularization and application.

Another object of the present invention is to provide the application of above-mentioned blue-ray organic electroluminescent material in organic electroluminescence device luminescent layer.

The structure of this organic electroluminescence device comprises conductive substrates and is sequentially laminated on the hole injection layer on conductive substrates surface, hole transport/electronic barrier layer, luminescent layer, electric transmission/hole blocking layer, electron injecting layer, cathode layer; Wherein:

Conductive substrates comprises substrate of glass, and is deposited on the anode layer of glass basic surface, and the material of this anode layer is indium tin oxide (ITO);

The material of hole injection layer is PEDOT:PSS;

The material of hole transport/electronic barrier layer is N, N'-phenylbenzene-N, N'-bis-(3-aminomethyl phenyl)-1,1'-biphenyl-4,4'-diamines (TPD);

The material of luminescent layer is blue-ray organic electroluminescent material described above, namely 2,2 '-(4,4 '-(2-tert-butyl anthracene-9,10-bis-base) two (4,1-penylenes)) two (1-phenyl-1H-phenanthro-[9,10-d] imidazoles);

The material of electric transmission/hole blocking layer is 4,7-phenylbenzene-1,10-phenanthroline (BPhen);

The material of electron injecting layer is LiF;

The material of cathode layer is Al.

In blue-ray organic electroluminescent material provided by the invention, imidazoles is a good electric transmission unit and thermal stability is good; Anthracene, phenanthrene have higher fluorescence quantum yield, using this material as emitting layer material, can improve the luminous efficiency of organic electroluminescence device.

The preparation method of above-mentioned blue-ray organic electroluminescent material, have employed better simply synthetic route, thus reduces technical process, and starting material are cheap and easy to get, and manufacturing cost is reduced.

Accompanying drawing explanation

Fig. 1 is the thermogravimetic analysis (TGA) figure of the blue-ray organic electroluminescent material that embodiment 1 obtains;

Fig. 2 is the organic electroluminescence device structural representation that embodiment 5 obtains.

Embodiment

In order to understand the content of patent of the present invention better, further illustrate technology case of the present invention below by concrete example and legend, specifically comprise material preparation and device preparation, but these embodiments do not limit the present invention, wherein, compd A, compd B are all purchased from scientific and technological in lark prestige.

Embodiment 1: the blue-ray organic electroluminescent material of the present embodiment, namely 2,2 '-(4,4 '-(2-tert-butyl anthracene-9,10-bis-base) two (4,1-penylenes)) two (1-phenyl-1H-phenanthro-s [9,10-d] imidazoles), preparation process is as follows:

Under argon shield, by 9, the bromo-2-tert-butyl anthracene (78mg, 0.2mmol) of 10-bis-, 2-(4-tetramethyl ethylene ketone boric acid ester phenyl)-1-phenyl-1H-phenanthro-[9,10-d] imidazoles (198mg, 0.4mmol) add in the flask filling 10ml toluene solvant, after abundant dissolving, salt of wormwood (2mL, 2mol/L) solution is joined in flask, vacuumize deoxygenation and be filled with argon gas, then bis-triphenylphosphipalladium palladium dichloride (5.6mg, 0.008mmol) is added; Flask is heated to 120 DEG C and carries out Suzuki coupling reaction 24h.Stopped reaction cool to room temperature, with dichloromethane extraction reaction solution repeatedly and merge organic phase, after this organic phase is spin-dried for after anhydrous magnesium sulfate drying, obtain crude product, this crude product adopts volume ratio to be that sherwood oil and the ethyl acetate of 10:1 mixes leacheate and be separated through silica gel column chromatography and obtain crystalline substance, this crystalline substance, under vacuo after 50 DEG C of dry 24h, obtains described blue-ray organic electroluminescent material.Productive rate is 78%.Mass spectrum: m/z971.2(M ⁺+ 1); Ultimate analysis (%) C ₇₂h ₅₀n ₄: theoretical value: C89.04, H5.19, N5.77; Measured value: C89.17, H5.24, N5.60.

Fig. 1 is the thermogravimetic analysis (TGA) figure of the blue-ray organic electroluminescent material that embodiment 1 obtains; Thermogravimetic analysis (TGA) is completed by the measurement of Perkin-Elmer Series7 Thermo System, and all measurements all complete in atmosphere at room temperature.As shown in Figure 1, the thermal weight loss temperature (T of blue-ray organic electroluminescent material 5% _d) be 393 DEG C.

Embodiment 2: the blue-ray organic electroluminescent material of the present embodiment, its structure is 2,2 '-(4,4 '-(2-tert-butyl anthracene-9,10-bis-base) two (4,1-penylene)) two (1-phenyl-1H-phenanthro-[9,10-d] imidazoles), preparation process is as follows:

Under nitrogen and argon gas gas mixture are protected; by 9; the bromo-2-tert-butyl anthracene of 10-bis-(118mg; 0.3mmol), 2-(4-tetramethyl ethylene ketone boric acid ester phenyl)-1-phenyl-1H-phenanthro-[9; 10-d] imidazoles (327mg; 0.66mmol) add in the two-mouth bottle of 50mL specification with 15mL tetrahydrofuran (THF); after the gas mixture air-discharging passing into nitrogen and argon gas after abundant dissolving is about 20min; then by tetra-triphenylphosphine palladium (4mg; 0.003mmol) add wherein; sodium bicarbonate (3mL, 2mol/L) solution is added again after abundant dissolving.After the gas mixture air-discharging of fully logical nitrogen and argon gas is about 10min again, two-mouth bottle is joined 70 DEG C and carry out Suzuki coupling reaction 48h.Stopped reaction cool to room temperature, with dichloromethane extraction reaction solution repeatedly and merge organic phase, after this organic phase is spin-dried for after anhydrous magnesium sulfate drying, obtain crude product, this crude product adopts volume ratio to be that sherwood oil and the ethyl acetate of 10:1 mixes leacheate and be separated through silica gel column chromatography and obtain crystalline substance, this crystalline substance, under vacuo after 50 DEG C of dry 24h, obtains described blue-ray organic electroluminescent material.Productive rate is 74%.

Embodiment 3: the blue-ray organic electroluminescent material of the present embodiment, its structure is 2,2 '-(4,4 '-(2-tert-butyl anthracene-9,10-bis-base) two (4,1-penylene)) two (1-phenyl-1H-phenanthro-[9,10-d] imidazoles), preparation process is as follows:

Under nitrogen protection, by 9, the bromo-2-tert-butyl anthracene of 10-bis-(118mg, 0.3mmol), 2-(4-tetramethyl ethylene ketone boric acid ester phenyl)-1-phenyl-1H-phenanthro-[9,10-d] imidazoles (342mg, 0.69mmol), palladium (3.5mg, 0.015mmol) He three (o-methyl-phenyl-) phosphine (21mg, 0.06mmol) join the N filling 12mL, in the flask of dinethylformamide, salt of wormwood (3mL, 2mol/L) solution is added, after logical nitrogen purge gas is about 30min in flask subsequently after abundant dissolving; Flask is heated to 130 DEG C and carries out Suzuki coupling reaction 12h.Stopped reaction cool to room temperature, with dichloromethane extraction reaction solution repeatedly and merge organic phase, after this organic phase is spin-dried for after anhydrous magnesium sulfate drying, obtain crude product, this crude product adopts volume ratio to be that sherwood oil and the ethyl acetate of 10:1 mixes leacheate and be separated through silica gel column chromatography and obtain crystalline substance, this crystalline substance, under vacuo after 50 DEG C of dry 24h, obtains described blue-ray organic electroluminescent material.Productive rate is 80%.

Embodiment 4: the blue-ray organic electroluminescent material of the present embodiment, its structure is 2,2 '-(4,4 '-(2-tert-butyl anthracene-9,10-bis-base) two (4,1-penylene)) two (1-phenyl-1H-phenanthro-[9,10-d] imidazoles), preparation process is as follows:

Under nitrogen protection; by 9; the bromo-2-tert-butyl anthracene of 10-bis-(118mg; 0.3mmol), 2-(4-tetramethyl ethylene ketone boric acid ester phenyl)-1-phenyl-1H-phenanthro-[9; 10-d] imidazoles (357mg; 0.72mmol), three or two argon benzyl acetone two palladium (9mg; 0.009mmol) with 2-dicyclohexyl phosphine-2 '; 6 '-dimethoxy-biphenyl (29mg; 0.072mmol) join the N filling 12mL; in the flask of dinethylformamide, after fully dissolving, add sodium carbonate (3mL, 2mol/L) solution.After in flask, logical nitrogen purge gas is about 30min subsequently; Flask is heated to 90 DEG C and carries out Suzuki coupling reaction 36h.Stopped reaction cool to room temperature, with dichloromethane extraction reaction solution repeatedly and merge organic phase, after this organic phase is spin-dried for after anhydrous magnesium sulfate drying, obtain crude product, this crude product adopts volume ratio to be that sherwood oil and the ethyl acetate of 10:1 mixes leacheate and be separated through silica gel column chromatography and obtain crystalline substance, this crystalline substance, under vacuo after 50 DEG C of dry 24h, obtains described blue-ray organic electroluminescent material.Productive rate is 86%.

Embodiment 5:

The present embodiment is organic electroluminescence device, the material of its luminescent layer is the blue-ray organic electroluminescent material that the present invention obtains, namely 2,2'-(4,4'-(2-tert-butyl anthracene-9,10-bis-base) two (4,1-penylenes)) two (1-phenyl-1H-phenanthro-[9,10-d] imidazoles).

As shown in Figure 2, the structure of this organic electroluminescence device comprises conductive substrates 1 and is sequentially laminated on the hole injection layer 2 on conductive substrates surface, hole transport/electronic barrier layer 3, luminescent layer 4, electric transmission/hole blocking layer 5, electron injecting layer 6, cathode layer 7; Wherein:

Conductive substrates 1 comprises substrate of glass, and is deposited on the anode layer of glass basic surface, and the material of this anode layer is indium tin oxide (ITO); ITO is combined with glass, is called for short ito glass;

The material of hole injection layer 2 is PEDOT:PSS;

The material of hole transport/electronic barrier layer 3 is N, N'-phenylbenzene-N, N'-bis-(3-aminomethyl phenyl)-1,1'-biphenyl-4,4'-diamines (TPD);

The material of luminescent layer 4 is 2,2 '-(4,4 '-(2-tert-butyl anthracene-9,10-bis-base) two (4,1-penylenes)) two (1-phenyl-1H-phenanthro-[9,10-d] imidazoles) (representing with P);

The material of electric transmission/hole blocking layer 5 is 4,7-phenylbenzene-1,10-phenanthroline (BPhen);

The material of electron injecting layer 6 is LiF;

The material of cathode layer 7 is Al.

The concrete grammar that this organic electroluminescence device makes is:

First, at the upper spin coating PEDOT:PSS of the anode layer (ITO) of the conductive substrates through cleaning, hole injection layer (PEDOT:PSS) after drying, is obtained;

Then, evaporation evaporation hole transport/electronic barrier layer (TPD), luminescent layer (P), electric transmission/hole blocking layer (BPhen), electron injecting layer (LiF), cathode layer (Al) is stacked gradually on hole injection layer surface.

Therefore, the structure of this organic electroluminescence device also can be expressed as:

Glass/ITO(150nm)/PEDOT:PSS (30nm)/TPD (40nm)/P(30nm)/BPhen (35nm)/LiF (1.5nm)/Al (150nm); Wherein, brace represents laminate structure, the one-tenth-value thickness 1/10 of each functional layer of the numeric representation in bracket.

Current versus brightness-the voltage characteristic of this organic electroluminescence device is tested, test completes by with Keithley source measuring system (Keithley2400Sourcemeter) correcting silicon photoelectric diode, and all measurements all complete in atmosphere at room temperature.Test result shows: the trigger voltage of device is 4.8V, at 1000cd/m ²brightness under, luminous efficiency is 5.5lm/W.

The above embodiment only have expressed several embodiment of the present invention, and it describes comparatively concrete and detailed, but therefore can not be interpreted as the restriction to the scope of the claims of the present invention.It should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection scope of the present invention.Therefore, the protection domain of patent of the present invention should be as the criterion with claims.

Claims (10)

1. a blue-ray organic electroluminescent material, is characterized in that, its structure is such as formula as follows:

2. a preparation method for blue-ray organic electroluminescent material as claimed in claim 1, is characterized in that, its step is as follows:

The compd A providing following structural formula to represent respectively and B,

Under oxygen-free environment, be dissolve mol ratio during the compd A of 1:2 ~ 2.4 and B are added into containing catalyzer and alkaline solution organic solvent, the mixing solutions obtained carries out Suzuki coupling reaction 12 ~ 48 hours at 70 ~ 130 DEG C, stopped reaction cool to room temperature, separating-purifying reaction solution, obtains the described blue-ray organic electroluminescent material described in following structural formula:

3. the preparation method of blue-ray organic electroluminescent material according to claim 2, is characterized in that, described catalyzer is bis-triphenylphosphipalladium palladium dichloride or tetra-triphenylphosphine palladium; The mol ratio of described catalyzer and described compd A is 1:20 ~ 1:100.

4. the preparation method of blue-ray organic electroluminescent material according to claim 2, is characterized in that, described catalyzer is the mixture of organic palladium and organophosphorus ligand, and the mol ratio of described organic palladium and organophosphorus ligand is 1:4 ~ 8; The mol ratio of described catalyzer and described compd A is 1:20 ~ 1:100.

5. the preparation method of blue-ray organic electroluminescent material according to claim 4, it is characterized in that, described organic palladium is palladium or three or two argon benzyl acetone two palladiums, described organophosphorus ligand is three (o-methyl-phenyl-) phosphines or 2-dicyclohexyl phosphine-2 ', 6 '-dimethoxy-biphenyl.

6. the preparation method of blue-ray organic electroluminescent material according to claim 5, it is characterized in that, described mixture is the mixture of palladium and three (o-methyl-phenyl-) phosphine, or described mixture is three or two argon benzyl acetone two palladiums and 2-dicyclohexyl phosphine-2 ', the mixture of 6 '-dimethoxy-biphenyl.

7. the preparation method of blue-ray organic electroluminescent material according to claim 2, is characterized in that, described alkaline solution is selected from least one in sodium carbonate solution, solution of potassium carbonate and sodium hydrogen carbonate solution; In described alkaline solution, the mol ratio of alkali solute and described compd A is 20:1.

8. the preparation method of blue-ray organic electroluminescent material according to claim 2, is characterized in that, described organic solvent is selected from as at least one in toluene, DMF, tetrahydrofuran (THF).

9., according to the preparation method of the arbitrary described blue-ray organic electroluminescent material of claim 2 to 8, it is characterized in that, described separating-purifying reaction solution comprises:

After Suzuki coupling reaction stops, with dichloromethane extraction reaction solution repeatedly and merge organic phase, after this organic phase is spin-dried for after anhydrous magnesium sulfate drying, obtain crude product, this crude product adopts volume ratio to be that sherwood oil and the ethyl acetate of 10:1 mixes leacheate and be separated through silica gel column chromatography and obtain crystalline substance, this crystalline substance, under vacuo after 50 DEG C of dry 24h, obtains described blue-ray organic electroluminescent material.

10. an organic electroluminescence device, is characterized in that, the material of its luminescent layer adopts blue-ray organic electroluminescent material according to claim 1.