KR20120038319A - Platinum complex for phosphorescent materials in organic light emitting diode - Google Patents

Abstract

PURPOSE: A platinum complex for phosphor material of an organic electroluminescence device is provided to have very high internal quantum efficiency, thereby using for blue luminescence material for an organic electroluminescence device. CONSTITUTION: A platinum complex for phosphor material is selected from organic metal compounds in chemical formula 1-4. In chemical formulas R1-R16 is selected from hydrogen, C1-C20 alkane, C2-C20 alkene, C2-C20 alkyne, isopropyl, t-butyl, methoxy, phenyloxy, benzyloxy, dimethylamino, diphenylamino, pyrrolidone, phenyl, fluorine, bromine, chlorine, iodine, cyano, nitro, trifluoromethyl. The wavelength of the phosphor of the platinum complex is 350-520 nm.

Description

Platinum complex for phosphorescent material of organic electroluminescent device {PLATINUM COMPLEX FOR PHOSPHORESCENT MATERIALS IN ORGANIC LIGHT EMITTING DIODE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a platinum complex for phosphorescent materials of organic electroluminescent devices, and to a binuclear platinum complex having a novel structure applicable to phosphorescent organic electroluminescent devices.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting material applied to an organic light emitting diode (OLED), and is applied as a light emitting device to a flat wall display television or a flat light emitting display device of a flexible organic device, or a light source for illumination of a light emitting device. The present invention relates to a phosphorescent material used in organic light emitting diodes that exhibit high luminous efficiency and low power consumption even at high luminance.

Today, the movement to the information society is accelerating, and accordingly, the need to exchange information anytime and anywhere is increasing. In addition to the increasing necessity, the proportion of flat panel display as a display is increasing. Among the flat panel displays, the organic light emitting diode display device is not only possible to be meridians by adopting an organic light emitting diode device capable of emitting light, but also has many advantages such as low voltage driving, wide viewing angle, and fast response speed. Therefore, the organic light emitting diode display device is rapidly growing as a next generation display.

An organic electroluminescent element using an organic material includes an anode, a cathode, and the organic light emitting layer described therebetween. The organic light emitting diode device has a configuration including a light emitting layer and a pair of electrodes disposed on both sides of the light emitting layer. When the electric field is applied between the two electrodes, electrons are injected from the cathode side, holes are injected from the anode side, and the electrons are combined with holes in the light emitting layer to form an excited state. The energy generated when returning to the ground state is emitted as light.

In this case, the organic light emitting layer may be divided into a low molecular weight light emitting material and a high molecular weight light emitting material. The low molecular weight light emitting material has a simple synthetic route compared to the high molecular weight light emitting material and can be easily purified to obtain a high purity material. As a result, the low molecular weight light emitting material can improve the efficiency and lifespan of the organic light emitting diode device. In addition, the low molecular light emitting material can easily implement the three primary color pixels through the appropriate molecular design. On the contrary, the polymer light emitting material can form an organic light emitting layer that is more durable than the low molecular weight light emitting material, and has an advantage of easy film forming process. However, the low molecular weight and the high molecular weight light emitting materials have a problem in that the luminous efficiency is low.

Light emission from organic light emitting diodes can be classified into fluorescence and phosphorescence. If fluorescence is emitted when organic molecules fall from the singlet excited state to the ground state, phosphorescence Is a phenomenon in which organic molecules emit light when they are dropped from the triplet excited state to the ground state.

In more detail, the valence band having a band formed by the bond orbits formed in the molecular electron orbit and the band formed by the semi-bonded orbits are called conducting bands. The highest energy level of the valence band is called HOMO (Highest Occupied Molecular Orbital), and the lowest energy level of the conductive band is called LUMO (Lowest Unoccupied Molecular Orbital), and the difference between HOMO energy and LUMO energy is the band gap ( Band Gap).

Electrons and holes injected into the organic light emitting layer constituting the organic light emitting device are recombined to form an exciton, and the light of the color corresponding to the band gap of the light emitting layer is realized in the process of converting the exciton electric energy into light energy. do. In this process, a singlet exciton with a spin of 1 and triplet excitons with a spin of 1 are produced at a ratio of 1: 3. According to the selection rule for the electric dipole transition, the spin quantum number should not change when transitioning from the excited state to the ground state. Since the ground state of the organic molecule is the singlet state, the singlet excitons can shine and transition to the ground state. However, triplet excitons glow and cannot transit. Therefore, the maximum quantum efficiency is generally limited to 25%.

However, if the spin-orbital coupling is large, the singlet form and the triplet form are mixed to cause inter-system crossing in the singlet-triplet state, so the triplet excitons are phosphorescent to the ground state. Can make a transition. After all, if the triplet excitons can be used to emit light, the internal quantum efficiency of the organic light emitting diode can theoretically be improved to 100%.

As a result, in recent years, the organic light emitting diode device is formed as a host of a phosphorescent dopant in the organic light emitting layer, thereby improving luminous efficiency of the organic light emitting diode device. This is because phosphorescence uses the light emitted from the excited triplet excited state compared to the fluorescence which uses only the singlet excited light for emitting light, and thus the external quantum efficiency can reach 100% (Baldo, et al., Nature, Vol. 395). 151-154, 1998).

When heavy metals such as ruthenium, iridium, and platinum are introduced into organic molecules, the complex is in singlet state ( ¹ MLCT) and triplet through spin-orbital coupling, which is caused by the heavy atom effect. The mixing of the steady state ( ³ MLCT) allows forbidden transitions and can effectively phosphorescent at room temperature.

As such, phosphorescent organic light emitting diodes, which can dramatically improve the luminous efficiency of organic light emitting diodes, were developed by SR Forrest professor of Princeton University and ME Thompson professor of USC in 1999. In particular, spin-orbit coupling Since is proportional to the square of the atomic number, complexes of heavy atoms such as iridium, platinum and europium (Eu) are known to have high phosphorescence efficiency. In this regard, C. Adachi et al. Published a phosphor bis (2-phenylpyridine) iridium (acetylacetonate) [(ppy) ₂ Ir (acac)] with iridium as its core metal. In addition, recently released materials called Ir (dfpmpy) ₂ (picN), Ir (dfpmpy) ₂ (ppc), Ir (dfpmpy) ₂ (anth), Ir (dfpmpy) ₂ (prz) having phosphorescence properties (Korean patent application There have been many reports of mononuclear complexes such as No. 10-2006-0130554).

However, research on phosphorescent materials using platinum is not very active. Platinum octaethylporphyrin (PtOET), a typical phosphorescent platinum complex, has an internal quantum efficiency of 60% in the red region of 641 nm (D. Eastwood, M. Gouterman. J. Mol . Spectrosc . 35 (1970) 359). Unfortunately, the life time is relatively long at 60, making it difficult to use commercially. And recently published papers on the ligands of complexes that can be used as phosphorescent materials using platinum complexes show that (C ^ N) ligands coordinated with para-phenyl pyridine (ppy) are sigma The bonded carbon is a very strong sigma electron donor and the pyridine group is a good pi-acceptor (L. Chassot, E. Muller. A. Von Zelewsky, Inorg . Chem . 23 (1984) 4249).

Williams et al. (Inorg. Chem. 42 (2003) 8609) described a green phosphorescent material of 480-580 nm in a complex obtained by coordinating bipyridylbenzene containing (N ^ C ^ N) in platinum metal. Internal quantum efficiency: 58 ~ 68%) was reported.

Yam, etc. (J. Organometal. Chem. 689 ( 2004), 1393) is released, but the results for the second nuclear platinum complex ([Pt2 (dppm) (CC -R) (CC-R)] +, most of the red In the region (590 to 640 nm), the luminescence properties are shown.In the case of platinum (II) complexes containing isoquinolinyl indazole ( Adv . Funct . Mater . 15 (2005) 223), the red region (553 nm and 635 nm) Very high internal quantum efficiency (internal quantum efficiency: 64 ~ 81%) and external quantum efficiency in electroluminescent device is 14.9% (24.57cd / A, 100mA /).

However, most of the platinum complexes reported so far show red light emission, and the results of platinum complexes with blue light are very insufficient, and the internal quantum efficiency of platinum complexes emitted from blue light is about 2%. Very low ( Inorg . Chem . 41 (2002) 3055).

According to the research trends so far, many complexes made of iridium as the center metal have been examined as phosphorescent materials, but recently, complexes made of platinum as the center metal have been examined ( Coord . Chem) . Rev. 250 (2006) 2093 and Coord. Chem . Rev. 252 (2008) 2596).

For example, it has been reported that an ortho-metalized platinum complex having a compound having an arylpyridine skeleton as a ligand and platinum as a central atom is useful as a phosphorescent light emitting material (for example, JP 2001-181617 A). Platinum complexes having bipyridine-biaryl skeleton compounds as ligands have also been reported (for example, JP-A-2002-175884). Moreover, the platinum complex using the tetradentate ligand in which the hydroxyl group was introduce | transduced into the bipyridine skeleton or the phenanthroline skeleton is reported (for example, Unexamined-Japanese-Patent No. 2005-524727). In addition, platinum complexes using tetradentate ligands in which a phenylpyridine skeleton or the like is linked with a crosslinking group have also been reported (WO2005 / 42444, JP 2005-310733, JP 2006-93542 and JP 2007) / 82284). Since the organic EL device using phosphorescence light emission is limited to red and green light emission as a current state, the application range as a color display is narrow, and development of the device which improved the light emission characteristic also about other colors is desired. In particular, if the green and blue light emitting elements can be improved, full colorization and whitening can be achieved, and the practical use of the phosphorescent EL element can be greatly improved.

As described above, various phosphorescent materials have been developed, but there are still a number of areas to be solved. In particular, there is an urgent need for the development of phosphorescent materials that emit light in the green and blue regions and the efficient supply of the materials.

The present invention has been made to solve the above-mentioned conventional problems, to provide a skeleton compound having excellent properties than conventional materials as a material applicable to the organic light emitting device for phosphorescence, that is applicable to an organic light emitting diode device An object is to provide a mononuclear or binuclear platinum complex of a new structure.

In order to solve the above problems,

The present invention provides a platinum complex for a phosphorescent material of an organic light emitting device, characterized in that selected from organometallic compounds represented by the following formulas (I) to (VI):

(I)

[Formula II]

[Formula III]

[Formula IV]

[Formula Ⅴ]

[Formula VI]

From here,

R ₁ to R ₁₆ are hydrogen, C ₁ Alkanes having from to C ₂₀ , carbon number C ₂ Alkenes having from to C ₂₀ , carbon number C ₂ To C ₂₀ of alkyne (alkyne), isopropyl, tert-butyl, methoxy, phenyloxy, benzyloxy, dimethylamino, diphenylamino Oh minno, pyrrolidine, phenyl, fluorine, bromine, chlorine, iodine, cyano, Nitro and trifluoromethyl.

It is preferable that the wavelength of the phosphorescence emission of the platinum complex for phosphorescent materials of the organic electroluminescent device is 350 to 520 nm which is a blue region.

The platinum complexes represented by the formulas (I) to (VI) of the present invention provide a novel platinum complex, which is a dopant material of organic EL, has a short wavelength luminescence property and exhibits very high quantum efficiency. Therefore, it can be applied as a blue light emitting material for organic electroluminescence and is very useful industrially.

1 is a graph showing the emission spectrum of the complex prepared from Example 1 of the present invention.
2 is a graph showing the emission spectrum of the complex prepared from Example 2 of the present invention.
3 is a graph showing the emission spectrum of the complex prepared from Example 3 of the present invention.
4 is a graph showing the emission spectrum of the complex prepared from Example 4 of the present invention.

The inventors conducted repeated studies to solve the above problems, and as a result, the platinum complex represented by the compounds represented by the following formulas (I) to (VI) exhibited excellent luminescence properties having short wavelength emission of blue series, Therefore, it was confirmed that the emission wavelength can be adjusted.

That is, the present invention relates to a platinum complex represented by the following formulas (I) to (VI). The characteristics of the compound represented by Formulas (I) to (VI) are as follows.

(I)

In the compound represented by the above formula (I), a compound composed of a bipyridine ligand (bpy) and another bipyridine ligand (BPB) having R ₁ to R ₅ as a substituent is coordinated to a mononuclear platinum atom.

[Formula II]

In the compound represented by the above formula (II), a compound composed of a bipyridine ligand (bpy) and another bipyridine ligand (BPB) having R ₁ to R ₅ as a substituent is coordinated with a binuclear platinum atom.

[Formula III]

In the compound represented by Formula III, a compound consisting of a phenanthroline ligand (PT) and a bipyridine-based ligand (BPB) having R ₄ to R ₇ as a substituent is coordinated with a mononuclear platinum atom.

[Formula IV]

In the compound represented by the above formula (IV), a compound composed of a phenanthroline ligand (PT) and a bipyridine-based ligand (BPB) having R ₄ to R ₉ as a substituent is coordinated with a heteronuclear platinum atom.

[Formula Ⅴ]

In the compound represented by the above formula (V), a compound composed of a benzoquinoline ligand (bqx) and a bipyridine-based ligand (BPB) having R ₁₀ to R ₁₆ as a substituent is coordinated with a mononuclear platinum atom.

[Formula VI]

In the compound represented by the above formula (VI), a compound composed of a benzoquinoline ligand (bqx) and a bipyridine-based ligand (BPB) having R ₁₀ to R ₁₆ as a substituent is coordinated with a dinuclear platinum atom.

The substituents R ₁ to R ₁₆ of the ligands used in the present invention are adjustable to change the light emission wavelength, and they may be used in the same kind of substituent or mixed with other substituents.

Examples of preferred substituents include hydrogen, C ₁ Alkanes having from to C ₂₀ , carbon number C ₂ Alkenes having from to C ₂₀ , carbon number C ₂ To C ₂₀ of alkyne (alkyne), isopropyl, tert-butyl, methoxy, phenyloxy, benzyloxy, dimethylamino, diphenylamino Oh minno, pyrrolidine, phenyl, fluorine, bromine, chlorine, iodine, cyano, Nitro, trifluoromethyl, and the like.

Hereinafter, the platinum complex represented by Formulas (I) to (VI) of the present invention will be described in more detail.

The compounds represented by the general formula (I) and the general formula (II) of the present invention are mononuclear or dinuclear complexes of tetragonal Pt (II) composed of two bipyridine. The compounds represented by the general formulas (III) and (IV) of the present invention are mononuclear or heteronuclear complexes of tetragonal Pt (II) composed of one bipyridine ligand and phenanthroline. In addition, the compounds represented by the formulas (V) and (VI) of the present invention are mononuclear or dinuclear complexes of tetragonal Pt (II) composed of one bipyridine ligand and one bisbenzoquinoline.

Substituents R ₁ to R ₁₆ of Formulas (I) to (VI) of the present invention are electron donor components or compounds containing electron acceptor components. Substituents include hydrogen and C ₁ Alkanes having from to C ₂₀ , carbon number C ₂ Alkenes having from to C ₂₀ , carbon number C ₂ To C ₂₀ of alkyne (alkyne), isopropyl, tert-butyl, methoxy, phenyloxy, benzyloxy, dimethylamino, diphenylamino Oh minno, pyrrolidine, phenyl, fluorine, bromine, chlorine, iodine, cyano, Nitro and trifluoromethyl and the like are composed of the same substituents or combined substituents. As a platinum complex of this invention, it is preferable that max (light emission maximum wavelength) of the phosphorescence obtained by the said platinum complex is 380 nm or more and 520 nm or less in green-blue light emitting material. Specific examples of the platinum complexes represented by the formulas (I) to (VI) of the present invention are shown below, but the present invention is not limited thereto.

The following describes in detail the manufacturing method of the platinum complex represented by the formula (I) to (VI) of the present invention.

Compounds in which one platinum is bonded as in Formulas (I), (III), and (V) of the present invention may be synthesized as follows.

Pt (bpy) Cl ₂ complex and 1,4-Bis (5'-2 ', 2 "-bipyridine) benzene, which acts as an intermediate crosslinking agent, are added to the water / ethanol solution in the same equivalence ratio in the range of 1 ~ 12 at 100 ~ 110 ℃. The mixture was refluxed for about an hour, cooled, and then added with excess NH ₄ PF ₆ (245 mg, 1.503 mmol) and stirred for 30 minutes. Next, the precipitate was filtered to remove the supernatant, and the precipitated solid was dissolved in CH ₃ CN solvent. After extraction, the extracted solution is dried.

Further, the platinum as Ⅱ formula, formula and formula Ⅳ Ⅵ of the present invention two compounds are combined in 1,4-Bis (5'-2 ' , 2 the amount of Pt (bpy) ₂ Cl synthesis of the cross-linking agent It is prepared by the same method except that it reacts with about 2.1 equivalents more than -bipyridine) benzene.

As a preferable synthesis example, the compound represented by general formula (I) of this invention can be manufactured as described in following formula (1).

( Synthetic  One)

The reaction temperature is usually 40 to 300 ° C, preferably 60 to 250 ° C, more preferably 80 to 200 ° C. Although reaction time changes with reaction temperature, other solvent, and an additive, it is suitably selected in 30 minutes-1 week, preferably 30 minutes-48 hours, More preferably, 1 to 12 hours.

As a platinum complex precursor used for manufacture of the compound of this invention, any of an inorganic platinum compound and an organic platinum complex can be used suitably. Preferred inorganic platinum compounds include platinum halides such as platinum chloride, platinum bromide and platinum iodide, and halogenated platinum salts such as sodium chloride platinum, potassium chloroplatinate, potassium bromide and potassium iodide. Platinum chloride and potassium chloroplatinate are more preferably used in terms of ease of availability and the like.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples.

In addition, the structure of the compound in the Example was confirmed using ¹ H { ¹³ C} -NMR (Bruker DRX-400).

JASCO FP-6500 was used as a device to investigate the luminescence properties. The excitation wavelength of the complex was based on the absorption wavelength. The equation for calculating the internal quantum efficiency (Φ _s ) of the complex based on the measured data is as follows. The reference light emitting material used in the present invention is [Ru (bpy) ₃ ] ²⁺ , and its internal quantum efficiency is 0.062.

Φ _s = (A _std / A _s ) (I _s / I _std ) Φ _std

Φ _s = quantum yield of the sample

A _s = absorption of the sample at the excitation wavelength

A _std = absorption of the stadard Complex at the excitation wavelength

I _s = point of maxima intensity in the corrected emission spectra (sample)

I _std = point of maxima intensity in the corrected emission spectra (standard complex)

Φ _std = quantum yield of standard complex ([Ru (bpy) ₃ ] (PF ₆ ) ₂ , Φ _std = 0.062)

[ Example  One]

Pt (4,4 ", 6,6'-tetramethyl-2,2'-bipyridiyl) Cl ₂ (0.09 mmol) and 1,4-Bis (5'-2 ', 2" -bipyridine) benzene (0.09 mmol) To 90ml of water and 90ml of methanol, and stirred at room temperature for about 3 hours, it was again refluxed at 100 ~ 110 ℃ 1 hour. After the reflux reaction, the mixture was cooled, and an excess of NH ₄ PF ₆ (245 mg, 1.503 mmol) was added thereto, followed by stirring for 30 minutes. Next, the precipitate was filtered to remove the supernatant. The precipitated solid was extracted with CH ₃ CN solvent. The extracted solution was dried to obtain a pale yellow complex 1 (yield 65%).

¹ H-NMR (DMSO-d ₆ / ppm): 9.12 (s), 8.73 (d), 8.52 (d), 8.47 (d), 8.37 (d), 8.15, 8.06 (t), 7.50 (t) 7.30 (s) 2.6 (s), 2.4 (s)

In the phosphorescence emission characteristics of the complex 1 according to the present embodiment, the light emission wavelength was found at 399 nm and 418 nm, and the emission time (τ) was 3.2 ms. In addition, the internal quantum efficiency was very high, 0.95.

[ Example  2]

After removing argon and vacuum three times to remove oxygen and water in 200cc Schlenk tube, add 1,4-bis (4'-2 ', 2 "-bipyridine) benzene (0.06mmol) and add 60cc of methanol. Pt (3,4,7,8-Tetramethy-1,10-phenanthroline) Cl ₂ (0.06 mmol) and 60 cc of distilled water were added thereto, followed by stirring for 3 hours, followed by reflux in a Schlenk tube containing the mixture. The mixture was refluxed under an argon gas atmosphere for 1 hour, and the mixture was cooled down to room temperature after completion of the reaction by TLC, followed by stirring with NH ₄ PF ₆ (0.158 mmol), followed by precipitation. The precipitate and the supernatant were separated, and the precipitate was dried in vacuo and extracted with acetonitrile to give a clean complex 2 (yield 70%).

¹ H-NMR (DMSO-d ₆ / ppm): 9.32 (s), 9.11 (s), 8.64 (d), 8.46 (dd), 8.33 (d), 7.98 (t), 7.49 (t), 2.74 ( s), 2.67 (s),

¹³ C-NMR (DMSO-d ₆ / ppm): 154.2, 151.7, 146.1, 139.1, 137.6, 136.5, 130.5, 128.9, 126.2, 122.2, 19.3, 169.9

In the phosphorescence emission characteristics of the complex 2 according to the present embodiment, the emission from the 325 nm incident light showed the maximum emission characteristics at 381, 397, and 418 nm, and the light emission lifetime (τ) was 2.1 ㎲. The internal quantum efficiency was very high at 0.98.

[ Example  3]

To remove oxygen and water in 100cc Schlenk tube, replace argon and vacuum three times, then add 1,4-bis (4'-2 ', 2 "-bipyridine) benzene (0.041mmol) and add 60cc of methanol. Pt (1,10-phenanthroline) Cl ₂ (0.05 mmol) and 60 cc of distilled water were added to the mixture, and the mixture was stirred for 3 hours. After confirming the completion of the reaction by TLC, the mixture was cooled at room temperature, and after cooling, NH ₄ PF ₆ (0.158 mmol) was added thereto, stirred, and precipitated, and the precipitate and the supernatant were separated using a filter paper. Then extracted with acetonitrile to obtain a clear complex 3 (yield 70%).

¹ H-NMR (DMSO-d ₆ / ppm): 9.59 (d), 9.19 (d), 8.40 (d). 8.32 (dd), 8.20 (s)

¹³ C-NMR (DMSO-d ₆ / ppm): 154.5, 144.0, 139.1, 132.3, 130.0, 129.6, 128.6, 128.1, 127.7, 122.2

In the phosphorescent emission characteristics of the complex 3 according to the present embodiment, the emission wavelength of the incident light at 327 nm was found to be 379, 390, and 402 nm, and the internal quantum efficiency was very high as 1.0. The light emission lifetime was 3.2 kW.

[ Example  4]

Pt (2,2'-benzoquinoline) Cl ₂ (0.09mmol) and 1,4-Bis (5'-2 ', 2 "-bipyridine) benzene (0.09mmol) were added to 90ml of water and 90ml of methanol. After stirring at room temperature, the mixture was refluxed for about 1 hour at 100 to 110 ° C. After refluxing, the mixture was cooled, and an excess of NH ₄ PF ₆ (245 mg, 1.503 mmol) was added thereto, followed by stirring for 30 minutes. The precipitate was then filtered to remove the supernatant The precipitated solid was extracted with CH ₃ CN solvent The extracted solution was dried to give a pale yellow complex 4 (yield 70%).

¹ H-NMR (CDCl ₃ / ppm): 8.83 (d), 8.43 (d), 8.31 (d), 7.94 (d), 7.84 (t), 7.63 (t) 7.52 (s), 7.0 (s)

Mass spectrometry (MALI-TOF): M ⁺ (m / e): 837.109

The internal quantum efficiency of the complex 4 according to the present example was 0.95, which was very high, and the emission time (life time) was 3.4 mW. The emission field was found to be 419, 432, and 508 nm in DMSO solution.

[ Comparative example ]

The maximum light emission wavelength of the cis-bis [2- (2'-thienyl) pyridinato] Pt (II) complex synthesized by Korean Patent Application Publication No. 10-2010-0042665 was 578 nm in the red region, and the lifetime was 2.2 ㎲. It was. The internal quantum efficiency was 0.27.

Although the present invention has been described with reference to the above-described embodiments and the accompanying drawings, other embodiments may be configured within the spirit and scope of the present invention. Therefore, the scope of the present invention is defined by the appended claims and equivalents thereof, and is not limited by the specific embodiments described herein.

Claims (2)

A platinum complex for a phosphorescent material of an organic light emitting device, characterized in that selected from organometallic compounds represented by the formula (I) to (VI):
(I)

[Formula II]

[Formula III]

[Formula IV]

[Formula Ⅴ]

[Formula VI]

From here,
R ₁ to R ₁₆ is hydrogen, the carbon number is C ₁ to C ₂₀ alkanes (alkane), the alkyne (alkyne) having a carbon number of the C ₂ to C ₂₀ of the alkene (alkene), a carbon number of C ₂ to C _20, isopropyl, Tert-butyl, methoxy, phenyloxy, benzyloxy, dimethylamino, diphenylamineno, pyrrolidine, phenyl, fluorine, bromine, chlorine, iodine, cyano, nitro and trifluoromethyl.
The method of claim 1,
Phosphorescence emission wavelength of the platinum complex for phosphorescent material of the organic light emitting device selected from the organometallic compounds represented by the above formulas (I) to (VI) is 350 ~ 520nm of the blue light emitting region, the phosphorescent material of the organic electroluminescent device Dragon platinum complex.

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