KR101149721B1 - high-efficiency organic light emitting material with thermal stability and preparation thereof - Google Patents

Abstract

The present invention relates to a high performance organic light emitting material having high thermal stability and a method of manufacturing the same, for organic light emitting diodes having high thermal stability and high glass transition temperature, which can improve the light emitting efficiency of an organic light emitting diode and increase its lifetime. It is an object to provide a hole transport material and a method of manufacturing the same.

An organic light emitting material used in the manufacture of the organic light emitting diode (OLED) represented by the following [Formula 1].

[Formula 1]

Ar ₁ to Ar ₄ in Formula 1 are the same as or different from each other. Ar ₁ to Ar ₄ is substituted or substituted with an alkyl group of C1 ~ C30 substituted or unsubstituted C1 ~ C30 alkyl group containing at least one hetero atom of S, N, O, P, Si and halogen atoms An aryl group including an unsubstituted aryl group, C3 to C30 heterocycle including at least one hetero atom of S, N, O, P, and Si atoms, and two or more adjacent ones of Ar ₁ to Ar ₄ are connected to each other; To form a ring. n and m are each an integer of 0-4. m is an integer of 1 or more and 4 or less, and m + n is 1-8.

Organic light emitting diode, OLED, hexaphenylbenzene, thermal stability, glass transition temperature, organic light emitting material, hole transport material]

Description

High-efficiency organic light emitting material with thermal stability and preparation method

The present invention relates to a high-performance organic light emitting material having high thermal stability and a method of manufacturing the same, and more particularly to a high thermal stability organic light emitting material used as a hole transporting material of the OLED and a method of manufacturing the same.

Organic light emitting diode (OLED) is a self-luminous type that is driven by low voltage, has a wide viewing angle, fast response time, light weight, and thinness, and can be manufactured.It is one of the next generation flat panel displays to replace LCD in the future. It is an active field.

U.S. Patent No. 4,356,429 discloses a two-layered organic light emitting diode comprising two organic layers sandwiched between an anode and a cathode. That is, the hole transport layer adjacent to the anode contains a hole transport material and has a function of transferring only holes to the light emitting layer mainly in the organic light emitting diode device. Similarly, the electron transport layer adjacent to the cathode contains an electron transport material, and the organic light emitting diode device having a two-layer structure selected to mainly transmit only electrons within the organic light emitting diode device achieves a high luminous efficiency and thus a large part of the organic light emitting diode. Improved technology Therefore, in terms of luminous efficiency, a multilayer structure including a hole transport layer such as a hole injection layer and a hole transporting layer, an electron transporting layer, a hole blocking layer, and the like Without the system, it is impossible to expect high efficiency and high luminance emission characteristics.

The organic light emitting diode should be a material in which the device material, in particular, the hole transport material is thermally and electrically stable, in addition to the device having a multilayer structure. Because molecules with low thermal stability due to heat generated in the device are low in crystal stability, rearrangement may occur, and eventually localized crystallization results in deterioration and destruction of the device by concentrating the electric field in this area. Because it comes.

Therefore, the organic layer is usually used in an amorphous state. Furthermore, since the organic light emitting diode is a current injection type device, if the material used has a low glass transition temperature (Tg), the heat generated during use causes the organic light emitting diode to deteriorate. It will shorten the life. In this respect, materials having a high glass transition temperature are preferred.

Representative examples of the hole transport material currently used include CuPC [copper phthalocyanine] of [Formula 2], 2-TNATA [4,4 ′, 4 ”-tris ( N- (naphthylene-2) of [Formula 3] -Yl) -N -phenylamino) -triphenylamine], TPD [ N, N' -diphenyl- N, N' -di (3-methylphenyl) -4,4'-diamino of the following [Formula 4]: Biphenyl] and NPB [ N, N' -di (naphthalen-1-yl) -N, N' -diphenylbenzidine] of the following [Formula 5].

Copper phthalocyanine (CuPc) of [Formula 2] is a representative material used as a hole injection layer due to its high conductivity, but due to its structural characteristics, it is applied to a full color OLED device due to a decrease in external quantum efficiency due to light absorption in the visible region. It is difficult to apply.

TPD of [Formula 4] shows superior hole transport ability, interfacial property with ITO, superior voltage than other materials in terms of applied voltage and brightness, but its low thermal stability prevents recrystallization due to Joule's heat. It is observed, which causes a decrease in the lifetime and EL characteristics of the device.

NPB (IP: 5.39eV) of [Formula 5] has a glass transition temperature (Tg) of 96 ° C., higher than 65 ° C. of TPD of [Formula 4], and high durability due to thermal stability, but NPB alone is used without a hole injection layer. In this case, the hole transport capacity is inferior. Therefore, attempts to supplement this by using the hole injection layer have been described, and the results are described in the US patent (USP 6617051 B1, 2003) and the European patent (EP0728828 A2, 1996), but they are still insufficient to realize a large screen and a long life. to be.

As described above, the hole transport material used in the conventional organic light emitting diode still has many problems and needs improvement. In particular, in order to improve the luminous efficiency of the organic light emitting diode and increase its lifetime, There is an urgent need for the development of materials with high glass transition temperatures.

In addition, Korean Patent Publication No. 2006-127201 discloses a hole transport material including polysiloxane, and Korean Patent Publication No. 2005-67945 discloses using an aluminum tris (8-hydroxyquinoline) doped with a polycyclic aromatic hydrocarbon as an electron transporting layer. An OLED is disclosed, and Korean Patent Laid-Open No. 2001-75614 discloses an OLED using a 2,7-fluorenyl-containing conjugated polymer as an electroluminescent material.

[Reference 1] US Patent No. 4,356,429

[Document 2] US Patent No. 6,617,051

[Patent 3] Japanese Patent Application Laid-Open No. 2004-244400

SUMMARY OF THE INVENTION An object of the present invention is to provide a hole transport material for an organic light emitting diode having a high thermal stability and a high glass transition temperature and a method of manufacturing the same, which can improve the luminous efficiency of an organic light emitting diode and increase its lifetime.

An organic light emitting material used in the manufacture of the organic light emitting diode (OLED) represented by the following [Formula 1].

Ar ₁ to Ar ₄ in Formula 1 are the same as or different from each other. Ar ₁ to Ar ₄ is substituted or substituted with an alkyl group of C1 ~ C30 substituted or unsubstituted C1 ~ C30 alkyl group containing at least one hetero atom of S, N, O, P, Si and halogen atoms An aryl group including an unsubstituted aryl group, C3 to C30 heterocycle including at least one hetero atom of S, N, O, P, and Si atoms, and two or more adjacent ones of Ar ₁ to Ar ₄ are connected to each other; To form a ring. n and m are each an integer of 0-4. m is an integer of 1 or more and 4 or less, and m + n is 1-8.

The hexaphenylbenzene derivatives of [Formula 1] are each prepared through an intermediate of the following [Formula 6]. The intermediate of [Formula 6] is dibromotetraphenylcyclopentadienone using diphenyl ether as a solvent without a special catalyst. Prepared by refluxing. [E. Maly, J. Am. Chem. Soc. 4306 (2007)

Here, the amination reaction for preparing [Formula 1] from the halo compound [Formula 6] synthesized by the above method is largely two methods.

The first method is the Ulmanmm reaction using a copper catalyst. Although not particularly limited, copper powder or copper sulfate (CuSO ₄ ) is suitable as a copper catalyst, and potassium carbonate or sodium carbonate is most suitable as a reaction base. For example, N, N -dimethylsulfoxide, nitrobenzene or decalin may be used without using a reaction solvent or having a high boiling point. Crown ether or poly (ethylene glycol) may be used to facilitate the reaction.

The second method is a method using a palladium catalyst, which performs an amination reaction using a palladium catalyst, a phosphine catalyst and a base under a suitable reaction solvent. The palladium catalyst used in the reaction is not particularly limited, but mainly palladium acetate or Tris (dibenzylideneacetone) dipalladium (0) is used, and the phosphine catalyst is also not particularly limited, so tri- ( o -tolyl) phosphine, 2,2'-bis (diphenylphosphino) -1, 1'-binafthyl, tri- (n-butyl) phosphine or tri- (t-butyl) phosphine and the like are used. As the reaction base, metal alkoxides such as sodium t-butoxide or potassium th-butoxide are used. The reaction solvent is not particularly limited and may be non-reactive with the reagents used and have a solubility that allows the reaction to proceed smoothly. Specific examples thereof include benzene, toluene, xylene, N, N -dimethylformamide, N, N -dimethylsulfoxide, and the like.

Specific examples of the hole transport material that enables the organic light emitting diode having a high luminous efficiency and a long lifetime obtained through the amination reaction include hexaphenylbenzene derivatives represented by the following [Formula 7]. . However, the present invention is not limited to these.

The hexaphenylbenzene derivatives according to the present invention synthesized by the method as described above are used as the hole transport material or the light emitting material of the organic light emitting diode. The hexaphenylbenzene derivatives according to the present invention will be described in detail in the following examples to purify by recrystallization and sublimation method due to the characteristics of the organic light emitting diode that requires high purity.

Using the hexaphenylbenzene derivative of the present invention [Formula 1] as a hole transport layer and a hole injection layer to fabricate an organic light emitting diode can solve the problem of low luminance and low luminous efficiency, which is the biggest disadvantage of the conventional organic light emitting diode In addition, it is possible to manufacture a full-color organic light emitting diode having a long lifespan due to its high glass transition temperature.

The construction of the present invention will be further clarified by the following examples, and the effect will be demonstrated by the comparative examples.

≪ Example 1 >

Next, the hexaphenylbenzene derivative of [Formula 7] was prepared by the 5-step reaction from [Scheme 1] to [Scheme 5].

1) First step

200 g (0.94 mol) of 4-bromophenylacetic acid was added to a 2,000 ml three-necked round bottom flask, and a solution of 180 g of sulfuric acid was slowly added to 1,000 ml of ethanol, and the mixture was refluxed for 4 hours, and then cooled to 1,500 ml. Extracted with ether. Subsequently, the mixture was washed several times with an aqueous solution of sodium bicarbonate, dried with anhydrous sodium sulfate, and then distilled under reduced pressure to obtain 180 g of a target compound (yield 80%).

¹ H NMR (DMSO): δ 7.41 (d, 2H), 7.13 (d, 2H), 4.13 (q, 2H), 3.53 (t, 2H), 1.22 (t, 3H).

2) second stage

Slowly add dropwise isopropyl magnesium dissolved in 150 ml of THF in a 2000 ml-3 round-bottomed flask to 4-bromophenyl ethylacetate dissolved in 300 ml of diethyl ether. After stirring for 1 hour, the mixture was further stirred at room temperature for 15 hours. Then, 300 ml of 10% ammonium chloride solution was added, 200 ml of 10% hydrochloric acid solution was slowly added thereto, and the separated organic layer was washed with 200 ml of 10% NaOH aqueous solution, and concentrated by distillation under reduced pressure. The concentrated liquid compound was added to a 2,000 ml three-neck round bottom flask, and refluxed with 1,000 ml of acetic acid and 200 ml of 18% hydrochloric acid for 6 hours, and then reduced temperature, extracted with 200 ml of ether, and distilled under reduced pressure to give 62 g of the target compound ( Yield 60%).

¹ H NMR (CDCl ₃ ): δ 7.44 (d, 4H), 7.00 (d, 4H), 3.67 (s, 5H)

3) third stage

In a 1,000 ml three-neck round bottom flask, 62 g (0.168 mol) of the compound prepared in the second step, 33.6 g (0.168 mol) of benzyl, and 300 ml of ethanol were added thereto, stirred for 10 minutes, and then dissolved in 40 ml of 4.70 g ( 0.084 mol) of KOH was added dropwise for 20 minutes, stirred at room temperature for 30 minutes, and filtered. The filtrate was then washed with distilled water and dried to give 68 g (yield 67%) of the title compound.

¹ H NMR (CDCl ₃ ): δ 6.90-7.37 (m, 28H)

4) Fourth Step

In a 250 ml three-neck round bottom flask, 48 g (0.089 mol) of the compound prepared in the third step, 17.4 g (0.098 mol) of diphenyl acetylene and 120 ml of diphenyl ester were added under reflux at a temperature of 220 ° C. for 4 hours. After cooling to room temperature, the mixture was washed with methanol and dried to obtain 55.2 g (yield 90%) of the title compound.

¹ H NMR (CDCl ₃ ) δ [ppm]: 7.05 (d, 2H), 6.79-6.88 (m, 10H), 6.4 (d, 2H).

5) 5th step

In a 250-ml three-necked round bottom flask, 25 g (0.036 mol) of the intermediate of [Formula 6] prepared in the fourth step was added under a nitrogen atmosphere and dissolved in 75 ml of o-xylene. 17.4 g (0.079 mol) of 1-PNA, 293 mg of P (t-Bu) ₃ , 163 mg of Pd (OAc) _2, and 8.33 g (0.086 mol) of Na ^t BuO were added and refluxed for 3 hours. Cooled. Subsequently, 75 ml of THF was added to increase fluidity. The mixture was poured into 1,500 ml of methanol, filtered, washed with methanol, and dried to obtain 44.6 g (yield 95%) of the title compound.

¹ H-NMR (DMSO-d ₆ ) δ [ppm]: 7.92 (d, 2H), 7.80 (d, 2H), 7.40-7.44 (m, 4H), 7.20 (t, 2H), 7.13 (t, 4H ), 7.06 (d, 2H), 6.80-6.89 (m, 22H), 6.69 (d, 4H), 6.63 (d, 4H), 6.48 (d, 4H).

MALDI-TOF MS: m / z 968.201, cal. 968.413.

<Example 2>

Next, hexaphenylbenzene derivatives of [Formula 11] were prepared through [Scheme 6] and [Scheme 7].

1) First step

In a 250-ml three-necked round bottom flask, 8.5 g (12.3 mmol) of the intermediate of [Formula 6] were added under a nitrogen atmosphere and dissolved in 17 ml of toluene. Then, 2.75 g (29.5 mmol) of aniline, 0.1 g (0.49 mmol) of P (t-Bu) ₃ , 225 mg (0.25 mmol) of Pd ₂ (dba) ₃ and 2.96 g (30.8 mmol) of Na ^t BuO were added thereto. The mixture was refluxed for 4 hours, cooled to room temperature, and 34 ml of MeOH was added thereto. The resulting solid was filtered and washed with MeOH to give 8.8 g (yield 100%) of the title compound.

MALDI-TOF MS: m / z 716.23, cal. 716.32.

2) second stage

7.7 g (10.8 mmol) of the compound prepared in the first step was added to a 250-ml three neck round bottom flask under nitrogen atmosphere, and dissolved in 27 ml of o-xylene. This solution was then added with 7.68 g (23.7 mmol) of N, N-diphenyl-N- (4-bromophenyl) amine, 87 mg (0.431 mmol) of P (t-Bu) ₃ and 48.4 mg (0.22) of Pd (OAc) _2. mmol) and Na ^t BuO 2.49g (25.9mmol) the input, and the mixture refluxed for 5 hours, allowed to cool to room temperature, then, poured into methanol, filtered, 1,000ml the product was washed with methanol and dried target compound 12.9g (yield 99%).

¹ H-NMR (DMSO-d ₆ ) δ [ppm]: 7.9 (d, 2H), 7.74 (d, 2H), 7.56 (d, 2H), 7.32-7.45 (m, 4H), 7.19 (t, 10H) ), 7.04 (d, 2H), 6.77-6.91 (m, 32H), 6.67 (d, 4H), 6.52 (d, 4H), 6.45 (d, 4H)

MALDI-TOF MS: m / z 1201.98, cal. 1202.53.

<Example 3>

Next, hexaphenylbenzene derivatives of [Formula 12] were prepared through [Scheme 8] and [Scheme 9].

1) First step

After drying the 250-ml three-necked round bottom flask completely, 8.5 g (12.3 mmol) of the above-formed Chemical Formula 6 was added under a nitrogen atmosphere and dissolved in 20 ml of toluene. 2.75 g (29.5 mmol) of aniline, 0.1 g (0.49 mmol) of P (t-Bu) ₃ , 225 mg (0.25 mmol) of Pd ₂ (dba) ₃ and 2.96 g (30.8 mmol) of Na ^t BuO were added to the solution. The mixture was refluxed for 2 hours, cooled to room temperature, and 50 ml of methanol was added thereto. The resulting solid was filtered, washed with methanol and dried to give 8.8 g (yield 100%) of the title compound.

MALDI-TOF MS: m / z 816.30, cal. 816.35.

2) second stage

Into a 250-ml three-necked round bottom flask, 8.8 g (10.8 mmol) prepared in the first step under nitrogen atmosphere were dissolved in 27 ml of o-xylene, and then N, N-diphenyl-N was added to the solution. - (4-bromophenyl) amine 7.68g (23.7mmol), P (t -Bu) 3 87mg (0.431mmol), Pd (OAc) 2 48.4mg (0.22mmol) and Na ^t BuO 2.49g (25.9mmol) Was added. The mixture was refluxed for 6 hours, cooled to room temperature, and added to 54 ml of THF to increase fluidity, and then added to 810 ml of MeOH. The resulting solid was filtered and washed with MeOH to give 14.0 g (99% yield) of the target compound.

¹ H-NMR (DMSO-d ₆ ) δ [ppm]: 7.90 (d, 2H), 7.72 (d, 2H), 7.57 (d, 2H), 7.35-7.40 (m, 4H), 7.19 (t, 10H) ), 7.08 (d, 2H), 6.75-6.99 (m, 36H), 6.65 (d, 4H), 6.50 (d, 4H), 6.48 (d, 4H)

MALDI-TOF MS: m / z 1303.2647, cal. 1302.56.

<Example 4-5, Comparative Example 1>

In [Example 4] and [Example 5], an organic light emitting diode was manufactured using [Formula 11] and [Formula 12] prepared in [Example 2] and [Example 3], respectively, and as a material of the light emitting layer. Is deposited to 200 Å of 4- (2,2-diphenyl vinyl) -1- [4- (2,2-diphenyl vinylphenyl] benzene (DPVBi), a well-known blue light emitting layer material, and Alq ₃ [tris (8) -Hydroxyquinoline) aluminum (III)] was deposited to a thickness of 500 kW to form an electron transport layer, and as the hole injection layer material, 2-TNATA of [Chemical Formula 3] was deposited to a thickness of 600 kW and a hole seed layer In the present invention, the NPB of [Formula 5] was manufactured to have an organic light emitting diode having a thickness of 300 Å, and 2-TNATA of [Formula 3] using [Formula 11] and [Formula 18] as the material of the hole injection layer as in the following example. Compared with.

<Example 4>

An organic light emitting diode was manufactured using the hexaphenylbenzene derivative of [Formula 11] prepared in [Example 2], and the physical properties and electrical characteristics of the organic light emitting diode were compared. The results are shown in the following [Table 1] together with the results of [Example 5] and [Comparative Example 1].

1) A transparent anode of indium tin oxide (ITO) was formed to a thickness of 750 kPa on a glass substrate having a width of 25 mm, a length of 75 mm, and a thickness of 1.1 mm.

2) The glass substrate was placed in a vacuum deposition apparatus to reduce the pressure to about 10 ^-7 torr, and the present invention [Formula 11] was deposited to a thickness of 600 kV to form a hole injection layer, and then NPB of the following [Formula 5] was 300 kV. It was deposited to a thickness of to form a hole transport layer.

3) DPVBi of Chemical Formula 17 was deposited to a thickness of 200 μs, and Alq ₃ [Tris (8-hydroxyquinoline) aluminum (III)] of Chemical Formula 16 was deposited to a thickness of 200 μs to form a light emitting layer. .

4) Finally, aluminum and lithium were simultaneously deposited to form a cathode having a thickness of 1,000 Å.

Luminescence test was performed by applying a voltage of 0 ~ 15V to the organic light emitting diode manufactured through the above process. The current density at each voltage, luminance, luminous efficiency, EL peak, color coordinates, highest luminance, and the like were measured, and the results are shown in Table 1 below.

Example 5

In the same manner as in [Example 4], an organic light emitting diode was manufactured using the hexaphenylbenzene derivative of [Formula 12] prepared in [Example 3], and the physical properties and electrical properties of the organic light emitting diode were compared. The results are shown in the following [Table 1] together with the results of [Example 4] and [Comparative Example 1].

Comparative Example 1

Using 2-TNATA (known material) of [Formula 3] to produce an organic light emitting diode in the same manner as in [Example 4], the organic light emitting diode and the physical properties and electrical properties were compared. The results are shown in the following [Table 1] together with the results of [Example 4] and [Example 5].

 Physical Properties and Electroluminescent Properties of Examples 4, 5 and Comparative Example 1 division Chemical formula Layer thickness
(A) Applied voltage
(V) Current density
(mA / cm ² ) efficiency
(cd / A) UV
λ _max (nm) PL
(nm) Tg
(℃) Example 4 Formula 11 600 4 0.723 2.400 342 421 143 Example 5 Formula 12 600 4 0.521 2.604 328 472 157 Comparative Example 1 Formula 3 600 4 0.132 2.836 334 485 105

(The abbreviations used in the table above are as follows: UV = ultraviolet absorption, PL = photoluminescence, Tg = glass transition temperature)

In order to confirm the optical properties, the UV maximum absorption wavelength (λ _max ) of [Chemical Formula 11] was measured and found to be 342 nm, and the light absorption (PL) spectrum of the compound of [Chemical Formula 11] was determined as the excitation wavelength As a result, the maximum peak was measured at 421nm. The measurement result is shown in [FIG. 1].

In addition, it was measured using a differential scanning calorimeter (DSC) to confirm the thermal stability for each material. As a result of the differential scanning calorimetry, it was observed that the glass transition temperature of most invention products including the above [Formula 11] and [Formula 12] was 140 ° C. or higher. Therefore, since it has a significantly higher glass transition temperature than 2-TNATA, which has been used as a conventional hole transport material, it has excellent thermal stability. It can be seen that. The measurement result for the compound of [Formula 11] is the same as in [2].

On the other hand, using the hole transport material according to the present invention as described above to produce an organic light emitting diode as in the above embodiment. As a preferred example of the present invention, the structure of the organic light emitting diode is shown in FIG. That is, a cathode and an anode exist on a transparent substrate, and an electron transport layer (ETL), an emission layer, a hole transport layer (HTL), and a hole injection layer (HIL) are stacked between the cathode and the anode, and the derivative according to the present invention is the emission layer. It can be used as a material of a hole transport layer or a hole injection layer. The result of measuring the electroluminescent property of [Example 4], [Example 5], and [Comparative Example 1] is as having described in the said [Table 1]. In this case, a conventional DPVBi represented by the following [Formula 17] was used as the light emitting layer material.

[Table 1] shows the organic light emission using the material of the light emitting layer as DPVBi and at the same applied voltage of 4V, using the compound of [Chemical Formula 11], [Chemical Formula 12] as a hole transport material, specifically a hole injection layer The light emitting characteristics were measured by fabricating a diode. The luminescence properties of the compounds of [Formula 11] and [Formula 12] and 2-TNATA (Comparative Example 1), which are all the same, were fabricated at 600 kV in the same manner.

In the case of using the compounds of [Formula 11] and [Formula 12] as the hole transport material, the current density was significantly higher than 5 V or less than the comparative material 2-TNATA (Formula 3), which may greatly contribute to lowering the driving voltage of the OLED device. It is considered to be. Specifically, as shown in the current density (IV) spectrum according to the applied voltage in Figure 4 the IV peak by the compounds of Examples 1 to 2 according to the present invention is lower voltage than 2-TNATA (Comparative Example 1) according to the prior art Shows excellent current characteristics. 5 shows the luminous efficiency according to the voltage.

1 is a UV / Vis for the hexaphenylbenzene derivative of the present invention [Formula 11]. Spectrometer and fluorescence (PL) spectral graphs.

Figure 2 is a differential scanning calorimeter (DSC) curve graph of the hexaphenylbenzene derivative of the present invention [Formula 11].

3 is a structure of an organic light emitting diode manufactured using the hexaphenylbenzene derivative of the present invention.

4 is a graph showing current density (I-V) spectrum according to applied voltages of [Formula 11] and [Formula 12] of the present invention.

5 is a light emission efficiency spectrum graph according to the voltage of [Formula 11] and [Formula 12] of the present invention.

Claims (5)

Hexaphenylbenzene derivative represented by the following [Formula 1] used as a hole transport material or a light emitting material of an organic light emitting diode. [Formula 1]

Ar ₁ to Ar ₄ in Formula 1 are the same as or different from each other. Ar ₁ to Ar ₄ is an aryl group (Ar2 is an arylene group) substituted or unsubstituted alkyl group of C1 ~ C20, n is 1, m is 2, para of the phenyl ring in a symmetric position in hexaphenylbenzene The amine group is bonded at the position. The hexaphenylbenzene derivative according to claim 1, wherein [Formula 1] is represented by the following [Formula 11] to [Formula 15]. [Formula 11]

[Chemical Formula 12]

[Formula 13]

[Formula 14]

[Formula 15]

A process for preparing [Formula 11] of claim 2, which is prepared by the following two steps [Scheme 6] and [Scheme 7]. Scheme 6

Scheme 7

A process for preparing [Formula 12] of claim 2, which is prepared by the following two steps of [Scheme 8] and [Scheme 9]. Scheme 8

Scheme 9

An organic electroluminescent device manufactured by using the hexaphenylbenzene derivative of claim 1 or 2 as a hole injection material, a hole transport material or a light emitting material.

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