KR20070119218A - Calixarene-based compound and an organic light emitting device employing the same - Google Patents

Abstract

A calixarene-based compound is provided to obtain a material having excellent electrical property and charge transportability, and to impart excellent luminance, lifespan, efficiency and power consumption characteristics to an organic light emitting device. A calixarene-based compound is represented by the following formula 1, wherein each of R1-R4 is an organic group with a electron transportability and each represents a C5-C30 substituted aryl group or C5-C30 substituted heteroaryl ring. Preferably, each of R1-R4 independently represents a C2-C20 fluorine-substituted aryl group or a heteroaryl group having a heteroatom in a C5-C20 ring.

Description

Calxarene-based compound and organic light emitting device using the same {Calixarene-based compound and an organic light emitting device employing the same}

1A to 1C are cross-sectional views briefly illustrating a structure of an organic light emitting diode according to the present invention.

2 illustrates an EL spectrum in the organic light emitting device according to Example 1 of the present invention.

3 is a view illustrating an organic light emitting diode according to Example 1 and Comparative Example 1 of the present invention;

A diagram showing a change in current density according to the driving voltage,

4 is a view showing a luminance change according to a driving voltage in the organic light emitting device according to Example 1 and Comparative Example 1 of the present invention,

5 illustrates an EL spectrum in the organic light emitting device according to Example 2 of the present invention.

6 is a view showing a change in current density according to a driving voltage in the organic light emitting device according to Example 2 and Comparative Example 1 of the present invention,

7 is a view showing a luminance change according to a driving voltage in the organic light emitting device according to Example 2 and Comparative Example 1 of the present invention.

The present invention relates to a calex arene-based compound and an organic light emitting device using the same, and more particularly, by employing a calex arene-based compound having an excellent electrical property and high electron injection or electron transport ability and an organic film including the same, The present invention relates to an organic light emitting device having improved driving voltage, brightness, and lifetime characteristics.

The organic light emitting device is a self-luminous display device, which has a wide viewing angle, excellent contrast, and fast response time. It has the advantage of being excellent and multicolored.

The organic light emitting device generally has a stacked structure of an anode / organic light emitting layer / cathode, and further an anode / organic light emitting layer / hole blocking layer / cathode, anode / organic layer by further stacking a hole blocking layer or an electron injection layer between the light emitting layer and the cathode. Light emitting layer / electron transport layer / cathode or anode / organic light emitting layer / hole blocking layer / electron injection layer / cathode.

As a material used in the light emitting layer, the hole transporting layer, and the electron transporting layer of the organic light emitting device, it is required to have characteristics such as high brightness, low driving voltage, light emission of various colors, and the like to develop a material that meets the requirements. It is necessary. As examples of such materials, low molecular materials such as copper phthalocyanine and starburst compounds, and polymer materials such as poly (p-phenylenevinylene) (PPV) and polyaniline have been developed.

However, the organic light emitting device having a material used to form the light emitting layer, the hole transport layer, and the electron transport layer known to date has a lot of room for improvement since the life, efficiency and power consumption characteristics do not reach a satisfactory level.

In order to solve the problems of the prior art, the technical problem of the present invention is to provide a calex arene-based compound that can improve the lifespan, efficiency and power consumption characteristics of the organic light emitting device, a manufacturing method and an organic light emitting device using the same will be.

The technical problem of the present invention is made by a calex arene-based compound represented by the following formula (1).

<Formula 1>

Wherein R ₁ to R ₄ are electron transporting organic groups, which are independently of each other a substituted aryl group of C 5 -C 30 or substituted hetero aryl ring of C 5 -C 30.

Another technical problem of the present invention is a compound of Formula 4,

It is made by a method for preparing a calex arene-based compound represented by the following formula (1) comprising the step of reacting one selected from the boron compound of formula (5) and tin compound of formula (6).

[Formula 4]

Wherein X is Br, Cl, or I.

[Formula 5]

Wherein R5 and R6 are hydrogen, methyl group, ethyl group, cyano group, fluorine, methoxy group, ethoxy group, or C2-C6 heterocyclic group, or R5 and R6 are linked to each other to form a C5-C6 carbon ring or C2- Forms a C6 heterocycle.

 [Formula 6]

In the above formula, R7 and R8 are methyl group, ethyl group, trifluoromethyl group, fluorine, C2-C6 heterocyclic group, or phenyl group.

<Formula 1>

Wherein R ₁ to R ₄ are electron transporting organic groups, which are independently of each other a substituted aryl group of C 5 -C 30 or substituted hetero aryl ring of C 5 -C 30.

Another technical problem of the present invention is one electrode; Second electrode; And at least an organic layer between the first electrode and the second electrode,

The organic film is made of an organic light-emitting device characterized in that it comprises the above-described calex arene-based compound.

Hereinafter, the present invention will be described in more detail.

In the calex arene-based compound of the general formula (1) of the present invention, the phenyl group constituting the calex arene structure has an electron transport group.

<Formula 1>

R ₁ to R ₄ is preferably an aryl group substituted with C ₂ -C 20 fluorine and a heteroaryl group substituted with a hetero atom in the ring of C 5 -C 20.

The above-described CalexArene-based compound is a difluorobenzonitrile-based or difluoro-based material having four chains of benzene ring linked to a carbon atom, and having electrical stability and high electron transport ability. By introducing at least two or four pyridine substituents, electron withdrawing groups are located at both ortho positions of both the carbon of which the cyano group is substituted in the benzonitrile ring having a high electron affinity and the nitrogen of the pyridine ring. The electron transport capacity is increased because the element has) in the structure. When these compounds are used as the electron injection layer, the electron transporting layer or the light emitting material of the organic light emitting device, the host material of the light emitting layer and the hole blocking layer, they are driven at a low voltage based on their excellent electron transporting ability, so that they exhibit high luminescence brightness and emit light for a long time. It is advantageous. In particular, the effect can be further enhanced when the molecule has two or more 2,6-difluorobenzonitrile groups or 2,6-difluoropyridine groups having excellent electron transporting ability.

The calex arene-based compounds represented by the general formula (1) according to the present invention are useful as an electron injection material, an electron transport material, and can also be used as a holdoff layer and a light emitting material.

In Formula 1, R1 to R4 are particularly aryl groups substituted with C 2 -C 20 fluorine and heteroaryl groups substituted with heteroatoms in the ring. Examples of heteroaryls include pyrazole, imidazole, oxazole, thiazole and triazole having two or more heteroatoms (1,2,3- or 1). Nitrogen-containing 5-membered cyclic hetero, such as 2,4-), tetrazole, oxadiazole (1,2,4-, 1,2,5- or 1,3,4-) And aromatic groups and groups derived from nitrogen-containing six-membered cyclic heteroaromatic compounds such as pyridine, pyridazine, pyrimidine, and triazine.

Examples of the fluorine-substituted aryl group are preferably a phenyl group substituted with 1 to 5 fluorine, and the positions other than fluorine are C1-C20 substituted or unsubstituted alkyl groups, aryl groups, C4-C30 substituted or unsubstituted hetero groups. Cyclic compounds, and adjacent groups may combine with each other to form a saturated or unsaturated carbon ring.

As the heteroaryl group, more preferably, a difluorobenzonitrile group and a difluoropyridine group are preferable, wherein two carbons of the difluoronitrile group and the difluoropyridine group include a hydrogen atom, a halogen, a cyano group, and a C1-C30 group. Substituents which represent a substituted or unsubstituted alkyl group, a C6-C30 substituted or unsubstituted aryl group, a C4-C30 substituted or unsubstituted heterocycle, and adjacent groups combine with each other to form a saturated or unsaturated carbon ring may be substituted.

In addition, all of R1 to R4 may be the same substituent or two identical substituents may be substituted for R1 = R3 and R2 = R4.

Representative structures of the novel compounds of the present invention are shown in the following table, but the present invention should not be limited to these compounds. In the following table, R represents a substituent in which R 1 = R 2 = R 3 = R 4 in Formula 1 are the same.

The calex arene-based compound of Formula 1 is particularly preferably a compound represented by the following formula (2) or (3).

 [Formula 2]

Wherein R5 and R6 are hydrogen, methyl group, ethyl group, cyano group, fluorine, methoxy group, ethoxy group, or C2-C6 heterocyclic group, or R5 and R6 are linked to each other to form a C5-C6 carbon ring or C2- Forms a C6 heterocycle.

[Formula 3]

In the above formula, R7 and R8 are methyl group, ethyl group, trifluoromethyl group, fluorine, C2-C6 hete logori group, or phenyl group.

The compound of the formula (1) according to the present invention is particularly preferably a compound represented by the following formula.

Wherein R 'and R "are independently of each other hydrogen or a C1-C10 alkyl group.

Looking at the method for producing a calex arene-based compound represented by Formula 1 as follows.

The callexarene-based compound represented by Formula 1 of the present invention is prepared by reacting a compound of Formula 4 with one selected from a boron compound of Formula 5 and a tin compound of Formula 6 below.

[Formula 4]

Wherein X is Br, Cl, or I.

[Formula 5]

Wherein R5 and R6 are hydrogen, methyl group, ethyl group, cyano group, fluorine, methoxy group, ethoxy group, or C2-C6 heterocyclic group, or R5 and R6 are linked to each other to form a C5-C6 carbon ring or C2- Forms a C6 heterocycle.

 [Formula 6]

In the above formula, R7 and R8 are methyl group, ethyl group, trifluoromethyl group, fluorine, C2-C6 heterocyclic group, or phenyl group.

The reaction takes place at 75 to 90 ° C. in the presence of bases such as triphenylphosphine and potassium carbonate. And the content of the boron compound of formula (5) or tin compound of formula (6) is preferably 4 to 5 moles based on 1 mole of the compound of formula (4).

Compound of Formula 4 is the first step of obtaining compound (A) from 1,3,5-trihalobenzene; Obtaining a compound (B) from the compound (A); A third step of obtaining compound (C) from the compound (B); A fourth step of reacting the compound (B) with the compound (C) to obtain a compound (D); And a fifth step of obtaining the compound of Formula 4 from the compound (D).

Wherein X is Br, Cl, or I.

In the first step, 1,3,5-trihalobenzene is mixed with an organic lithium compound such as n-butyllithium and a solvent, and mixed with a formate compound such as methyl formate to react compound (A). You can get it. This reaction temperature is preferably -70 to -80 ° C. And the content of the formate compound is preferably 0.5 to 0.6 moles based on 1 mole of 1,3,5-trihalobenzene.

The compound (A) can be mixed with red P and acetic acid to undergo a reduction reaction to obtain a compound (B). Herein, the content of red P is 3 to 3.5 mol based on 1 mol of compound (A), and the content of acetic acid is preferably 200 to 250 mol based on 1 mol of compound (A).

Subsequently, the compound (B) is reacted with an organolithium compound, which is then reacted with methylformanalide to obtain the compound (C). Herein, the content of methylformanalide is 1 to 1.1 moles based on 1 mole of the compound (B), and the reaction temperature is preferably -78 to -80 ° C.

The compound (D) can be obtained by reacting the compound (B) with an organolithium compound such as t-butyllithium and then reacting with the compound (C). The compound (E) can be obtained by mixing red P and acetic acid with this compound (D).

The calex arene-based compound represented by the general formula (1) of the present invention is excellent in luminescence properties and hole transporting properties, and thus is useful as a blue light emitting material, a green, red phosphorescent and fluorescent host material, and a hole transporting material.

An organic light emitting device according to the present invention includes a first electrode, a second electrode, and at least an organic film between the first electrode and the second electrode, wherein the organic film is a Calex arene-based compound represented by Formula 1 as described above. It may include.

More specifically, it may include an electron injection layer, an electron transport layer, or a light emitting layer comprising a light emitting layer and the triazine-based compound represented by Formula 1 between the first electrode and the second electrode.

The structure of the organic light emitting device of the present invention is very diverse.

It may further include one or more layers selected from the group consisting of a hole injection layer, an electron blocking layer, a hole blocking layer, an electron transport layer and an electron injection layer between the first electrode and the second electrode.

More specifically, various embodiments of the organic light emitting device according to the present invention refer to Figures 1a, 1b and 1c. The organic light emitting device of Figure 1a has a structure consisting of a first electrode / hole transport layer / light emitting layer / charge transport layer / a second electrode, the organic light emitting device of Figure 1b has a first electrode / hole injection layer / hole transport layer / light emitting layer / electron transport layer It has a structure consisting of an electron injection layer and a second electrode. In addition, the organic light emitting device of FIG. 1C has a structure of a first electrode / hole injection layer / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / electron injection layer / second electrode. At this time, it is a matter of course that the electron transport layer, the electron injection layer or the light emitting layer may include a Calex arene-based compound represented by the formula (1).

The light emitting layer of the organic light emitting device according to the present invention may include a phosphorescent or fluorescent dopant including red, green, blue or white. Among these, the phosphorescent dopant may be an organometallic compound including at least one element selected from the group consisting of Ir, Pt, Os, Ti, Zr, Hf, Eu, Tb, and Tm.

Hereinafter, a method of manufacturing an organic light emitting diode according to the present invention will be described with reference to the organic light emitting diode illustrated in FIG. 1C.

First, a first electrode material having a high work function on the substrate is formed by vapor deposition or sputtering to form a first electrode. The first electrode may be an anode. Herein, a substrate used in a conventional organic light emitting device is used, and an organic substrate or a transparent plastic substrate having excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and waterproofness is preferable. As the material for the first electrode, transparent indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO 2), zinc oxide (ZnO), and the like are used.

Next, a hole injection layer HIL may be formed on the first electrode by using various methods such as vacuum deposition, spin coating, casting, and LB.

When the hole injection layer is formed by vacuum deposition, the deposition conditions vary depending on the compound used as the material of the hole injection layer, the structure and thermal properties of the hole injection layer as desired, and the deposition temperature is generally 50 to 500 ° C., It is preferable that a vacuum degree of 10 ^-8 to 10 ^-3 torr, a deposition rate of 0.01 to 100 mW / sec, and a film thickness are usually appropriately selected in the range of 10 mV to 5 m.

The hole injection layer material is not particularly limited, and for example, a phthalocyanine compound such as copper phthalocyanine disclosed in U.S. Patent No. 4,356,429 or a starburst amine derivative described in Advanced Material, 6, p.677 (1994). Retained TCTA, m-MTDATA, m-MTDAPB, etc. can be used as the hole injection layer. The chemical formula of m-MTDATA is referred to the following chemical formula.

Next, a hole transport layer (HTL) may be formed on the hole injection layer by using various methods such as vacuum deposition, spin coating, cast, and LB. When the hole transport layer is formed by a vacuum deposition method, the deposition conditions vary depending on the compound used, but are generally selected from the ranges of conditions almost the same as that of the hole injection layer.

The hole transport layer material is not particularly limited and may be selected from any of known ones used in the hole transport layer. As a general hole transporting material, carbazole derivatives such as N-phenylcarbazole and polyvinylcarbazole, N, N'-bis (3-methylphenyl) -N, N'-diphenyl- [1,1-biphenyl ] 4,4'-diamine (TPD), N, N'-di (naphthalen-1-yl) -N, N'-diphenyl benzidine (α-NPD), and other conventional amine derivatives having aromatic condensed rings Etc. are used. For the formula of α-NPD, see the formula below.

Next, the light emitting layer EML may be formed on the hole transport layer by using a vacuum deposition method, a spin coating method, a cast method, an LB method, or the like. In the case of forming the light emitting layer by vacuum deposition, the deposition conditions vary depending on the compound used, but are generally selected from the ranges of conditions substantially the same as those of forming the hole injection layer.

The light emitting layer material is not particularly limited and may be arbitrarily selected from known materials, known host materials, and dopant materials. In the case of the host material, for example, Alq ₃ or CBP (4,4'-N, N'-dicarbazole-biphenyl) or the like can be used. On the other hand, for the dopant, for example, as the fluorescent dopant, IDE102, IDE105 and C545T available from Hayamibara Corp., etc., which can be purchased from Idemitsu Corp., can be used. , Green phosphorescent dopant Ir (PPy) ₃ (PPy = 2-phenylpyridine), F2Irpic which is a blue phosphorescent dopant, red phosphorescent dopant RD 61 by UDC, etc. can be used. In addition, a dopant represented by the following formula can be used.

Doping concentration is not particularly limited, but the content of the dopant is generally 0.01 to 15 parts by weight based on 100 parts by weight of the host and the dopant.

In the case of using the phosphorescent dopant in the light emitting layer, the hole blocking material (HBL) may be further laminated by vacuum deposition or spin coating in order to prevent the triplet excitons or holes from diffusing into the electron transport layer. A well-known material can also be used as a hole blocking material which can be used at this time. Known hole blocking materials include, for example, oxadiazole derivatives, triazole derivatives, phenanthroline derivatives, hole blocking materials described in JP 11-329734 (A1), BCP, and the like.

Next, the electron transport layer (ETL) is formed using various methods such as vacuum deposition, spin coating, and casting. The electron transport layer material has a function of stably transporting electrons injected from an electron injection electrode (Cathode), using a known material such as quinoline derivatives, especially tris (8-quinolinorate) aluminum (Alq ₃ ), or the like. The calex arene type compound represented by General formula (1) of this invention is used.

In addition, an electron injection layer (EIL), which is a material having a function of facilitating injection of electrons from the cathode, may be stacked on the electron transport layer, which does not particularly limit the material.

As the electron injection layer, a material such as LiF, NaCl, CsF, Li 2 O, BaO, or the like may be used, and a calexarene compound represented by Chemical Formula 1 of the present invention may be used.

The deposition conditions of the hole blocking layer (HBL), the electron transport layer (ETL), and the electron injection layer (EIL) vary depending on the compound used, but are generally selected from the same range of conditions as the formation of the hole injection layer.

Finally, the second electrode may be formed on the electron injection layer by using a method such as vacuum deposition or sputtering. The second electrode may be used as a cathode. As the metal for forming the second electrode, a metal, an alloy, an electrically conductive compound having a low work function, and a mixture thereof may be used. Specific examples include lithium (Li), magnesium (Mg), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag), and the like. Can be mentioned. In addition, a transmissive cathode using ITO and IZO may be used to obtain the front light emitting device.

The organic light emitting device of the present invention includes a first electrode, a hole injection layer (HIL), a hole transport layer (HTL), a light emitting layer (EML), a hole blocking layer (HBL), an electron transport layer (ETL), an electron injection layer shown in FIG. (EIL) and the organic light emitting element of the second electrode structure, as well as the structure of the organic light emitting element of various structures are possible, it is also possible to further form one or two intermediate layers as needed.

Hereinafter, specific examples and examples of the compounds 1 and 15, which are representative examples of the organic light emitting compound having a calixarene derivative having four substituents in the molecule of the present invention as a basic skeleton, are specifically illustrated. The invention is not limited to the following examples. The compounds of Formula 1 may be useful as blue light emitting materials, green, red phosphorescent and fluorescent host materials as light emitting materials having excellent light emission characteristics and hole transport characteristics, and may also be used as electron transport materials or electron injection materials.

Synthesis Example  1 (intermediate compound E)

Intermediate compound E was synthesized via the reaction route of Chemical Scheme 1 below.

Scheme 1

Synthesis of Intermediate (A)

28.3 g (90 mmol) of 2,4,6-tribromotoluene was dissolved in 600 mL of diethyl ether, cooled to -78 ^° C., and 36.0 mL (90 mmol, 2.5 M in Hexane) of normal butyl lithium was slowly added. After stirring the reaction mixture at -78 ^o C for about 1 hour, 2.7 mL (44 mmol) of methyl formate was added at the same temperature, which was then slowly raised to room temperature and stirred for 16 hours, followed by distilled water and di Washed with ethyl ether. The washed diethyl ether layer was dried over MgSO ₄ and dried under reduced pressure to obtain a crude product, which was recrystallized from boiling hexane to give 19.3 g (yield 86%) of intermediate A as colorless crystals.

Intermediate (A): mp 170 ^o C, ¹ H NMR (CDCl ₃ , 400 MHz) δ (ppm) 7.61 (t, 2H), 7.43 (d, 4H), 5.68 (d, 1H), 2.35 (d, 1H) ; ¹³ C NMR (CDCl ₃ , 100 MHz) δ (ppm) 146.1, 133.8, 128.3, 123.4, 73.7.

Synthesis of Intermediate (B)

Intermediate (A) 72.8 g (146 mmol), red P 15.3 g (492 mmol) and iodine 7.41 g (29.2 mmol) were mixed, dissolved in 1800 mL of acetic acid and heated to reflux for 42 hours. After the reaction, water was added to the solution, and the resulting solid was filtered and washed with water and methanol. The resulting solid was soxhlet extracted with chloroform to give 63 g (89% yield) of intermediate (B) as a white solid.

Intermediate (B): mp 192 ^o C, ¹ H NMR (CDCl ₃ , 400 MHz) δ (ppm) 7.55 (s, 2H), 7.23 (s, 4H), 3.84 (2H); ¹³ C NMR (CDCl ₃ , 100 MHz) δ (ppm) 143.1, 132.6, 130.72, 123.3, 40.0.

Synthesis of Intermediate (C)

Dissolve 4.01 g (8.29 mmol) of intermediate (B) in 100 mL of THF, cool to -78 ^o C, and slowly add 19.5 mL (33.2 mmol, 1.7 M in pentane) of t-butyllithium. After stirring at −78 ^° C. for 1 h, 10.4 mL (16.6 mmol, 1.6 M in THF) of methylformanilide were added at the same temperature. Slowly raise the temperature to 0 ^o C and stir for 16 hours, then wash with distilled water and chloroform at room temperature. Recrystallization from chloroform and hexane gave 1.95 g (yield 61%) of an intermediate (C) as a yellow solid.

Intermediate (C): mp> 200 ^o C dec., ¹ H NMR (CDCl ₃ , 400 MHz) δ (ppm) 9.93 (s, 2H), 7.90 (s, 2H), 7.62 (s, 2H), 7.58 (s , 2H), 4.08 (s, 2H); ¹³ C NMR (CDCl ₃ , 100 MHz) δ (ppm) 190.5, 142.5, 138.3, 137.6, 131.3, 128.3, 123.8, 40.5.

Synthesis of Intermediates (D) and (E)

Dissolve 1.27 g (2.62 mmol) of intermediate (B) in 50 mL of THF, cool to -78 ^o C, and then slowly add 6.15 mL (10.5 mmol, 1.7 M in pentane) of t-butyllithium. After stirring for 1 h at -78 ^o C, 1.00 g (2.62 mmol) of intermediate (C) are dissolved in 50 mL of THF and added slowly at the same temperature. slowly  The temperature was raised to room temperature and stirred for 36 hours, followed by extraction three times with 50 mL of distilled water and ethyl acetate at room temperature. The combined organic layers were dried over magnesium sulfate, and the residue obtained by evaporation of the solvent was recrystallized with chloroform and THF to give the intermediate (D) as a white solid, which was used as it was in the next reaction.

2.04 g of Intermediate (D) and 4.45 g (˜150 mmol) and 1.08 g (4.2 mmol) of iodine were dissolved in 100 mL of acetic acid and heated to reflux for 48 hours. Acetic acid and iodine were removed by boiling, and the remaining solid was washed with water and methanol and soxhlet extracted with chloroform to obtain the intermediate (E) as a white solid (0.83 g, yield> 40%).

Intermediate (D): mp> 290 ^o C dec., ¹ H NMR (CDCl ₃ , 400 MHz) δ (ppm) 7.50, 7.47 (s, 8H), 7.20, 7.14 (s, 4H), 6.13 (bs, 2H) , 5.62 (bs, 2H), 3.84 (s, 4H); ¹³ C NMR (CDCl ₃ , 100 MHz) δ (ppm) 149.4, 149.3, 144.7, 130.9, 127.5, 127.4, 125.7, 122.6, 73.8, 41.2.

Intermediate (E): mp> 290 ^° C dec., ¹ H NMR (CDCl ₃ , 400 MHz) δ (ppm) 7.23 (s, 8H), 6.54 (s, 4H), 3.76 (s, 8H); ¹³ C NMR (CDCl ₃ , 100 MHz) δ (ppm) 142.8, 130.0, 127.5, 12.6, 41.0.

Synthesis of Compounds 1 and 15

Compound 1 was synthesized through the reaction route of Scheme 2 below.

Scheme 2

　　　　　　　　　　　

Intermediate F  synthesis

6.0 mL (12.0 mmol) of LDA (Lithium diisopropylamide) was added to diethyl ether (50 mL), and 0.91 mL (10.0 mmol) of difluoropyridine was added dropwise at -78 ° C, followed by stirring for 1 hour. 1.4 mL (12.5 mmol) of trimethylborate are added to the reaction mixture and the temperature is raised to room temperature and stirred for 1 hour. 5% aqueous sodium hydroxide solution (20 mL) is added and the aqueous layer is neutralized with 3 N aqueous hydrochloric acid solution. The aqueous layer is extracted three times with 20 mL of ethyl acetate. The combined organic layers were dried over magnesium sulfate and the residue obtained by evaporation of the solvent was dried under vacuum to yield 1.03 g (yield 65%) of white solid F.

Synthesis of Compound 1

Dissolve Intermediate F 1.27 g (8.0 mmol) and Intermediate E 1.35 g (2.0 mmol) in 20 mL THF, add 289 mg (0.25 mmol) of tetrakistriphenylphosphinepalladium, and add 6.91 g (50 mmol) of potassium carbonate to 15 mL of distilled water. The aqueous solution dissolved in was added and stirred at 75 ⁰ C for 12 hours. The reaction solution was extracted three times with 10 mL of ethyl acetate. The combined organic layers were dried over magnesium sulfate, and the residue obtained by evaporation of the solvent was separated and purified by silica gel column chromatography to obtain 325 mg (yield 40%) of compound 1 as a white solid. The structure was confirmed by ¹ H NMR.

¹ H NMR (CDCl ₃ , 300 MHz) δ (ppm) 7.63-7.55 (m, 4H), 7.27 (s, 8H), 7.09-7.05 (m, 4H), 6.53 (s, 4H), 4.06 (s, 8H ); ¹³ C NMR (CDCl ₃ , 100 MHz) δ (ppm) 170.4, 170.3, 167.9, 167.8, 164.36, 158.0, 157.9, 155.5, 155.4, 151.1, 150.1, 143.4, 143.3, 141.9, 128.8, 128.7, 128.6, 110.0, 109.9 , 109.7, 109.6, 106.7, 106.6, 106.4, 106.3, 42.7.

Compound 15 was synthesized through the reaction route of Scheme 3 below.

Scheme 3

Intermediate Of G  synthesis

To a solution of 1.4 g (10.0 mmol) of difluorobenzonitrile and diethyl ether (50 mL) was added dropwise 6.0 mL (12.0 mmol) of LDA (Lithium diisopropylamide) at -78 ° C, followed by stirring for 1 hour. 12.5 mL (12.5 mmol) of 1M trimethyltin chloride solution is added to the reaction mixture, the temperature is raised to room temperature and stirred for 1 hour. 5% aqueous sodium hydroxide solution (20 mL) is added and the aqueous layer is neutralized with 3 N aqueous hydrochloric acid solution. The aqueous layer is extracted three times with 20 mL of ethyl acetate. The combined organic layers were dried over magnesium sulfate and the residue obtained by evaporation of the solvent was dried under vacuum to obtain 2.0 g of a white solid G (yield 66%).

compound 15 of  synthesis

Dissolve Intermediate G 2.41 g (8.0 mmol) and Intermediate E 1.35 g (2.0 mmol) in 20 mL DMF, then add tetrakistriphenylphosphinepalladium (577 mg, 0.50 mmol), K ₂ CO ₃ (3.44 g, 25 mmol), and add 120 Stir at ⁰ C for 2 hours. The reaction solution was extracted three times with 10 mL of ethyl ether. The combined organic layer was dried over magnesium sulfate, and the residue obtained by evaporation of the solvent was separated and purified by silica gel column chromatography to obtain 410 mg (yield 45%) of compound 15 as a white solid. The structure was confirmed by ¹ H NMR.

¹ H NMR (CDCl ₃ , 300 MHz) δ (ppm) 7.83 (q, 4H), 7.28 (s, 8H), 7.27-7.21 (m, 4H), 6.44 (s, 4H), 4.09 (s, 8H); ¹³ C NMR (CDCl ₃ , 100 MHz) δ (ppm) 170.5, 170.4, 167.9, 167.8, 162.6, 162.4, 162.3, 159.8, 159.7, 156.2, 156.1, 141.3, 141.2, 140.2, 128.2, 128.1, 128.0, 125.8, 125.5 , 114.2, 114.1, 112.2, 112.0, 92.8, 92.5, 92.2, 42.9.

Example  One

Anode cut corning 15Ω / m ² (1200Å) ITO glass substrate into 50mm x 50mm x 0.7mm size and ultrasonically clean for 5 minutes in isopropyl alcohol and pure water, and then irradiate with ultraviolet rays for 30 minutes and ozone The glass substrate was installed in a vacuum deposition apparatus after exposure to cleaning. The IDE 406, a well-known material well known as a hole injection layer, was first vacuum deposited on the substrate to a thickness of 600 Å. Subsequently, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPB) was vacuum deposited to a thickness of 300 로서 as a hole transport compound to form a hole transport layer.

After forming the hole transport layer as described above, Alq ₃ , a known green fluorescent host, and C545T, a known green fluorescent dopant, were simultaneously deposited at a weight ratio of 98: 2 on the hole transport layer to form a light emitting layer having a thickness of 200 Å.

Subsequently, Compound 1 was deposited to a thickness of 300 kV with the electron transport layer, and then LiF, an alkali metal halide, was deposited to a thickness of 10 kW with the electron injection layer, and Al was vacuum deposited to a thickness of 3000 kW (cathode electrode) to form LiF / An organic light emitting device was manufactured by forming an Al electrode.

The driving voltage (turn-on voltage) of this device was 2.5V, and the current density of 21.97mA / cm 2 and emission luminance of 2178cd / m 2 was obtained at the applied voltage of 6.0V. / A. The EL emission spectrum of this device is shown in FIG.

Comparative example  One

In Example 1, an organic light emitting device was manufactured in the same manner as in Example 1 except that Alq ₃ was used instead of Compound 1 forming the electron transport layer.

The device had a driving voltage of 3.0 V, a current density of 7.77 mA / cm 2 and an emission luminance of 905.5 cd / m 2 at an applied voltage of 6.0 V. The color coordinates of (0.30, 0.64) were 10.55 cd / A.

As a result of using the compound 1 according to the present invention as the electron transport layer, the driving voltage was lowered by 0.5V due to the improvement of the electron injection and transport ability, the applied voltage was lowered by about 1V at the same current value, and the current density value was lowered. It was confirmed that the luminance value increased as it was improved. As a result, it was possible to achieve a low power consumption organic electroluminescent device capable of high brightness with low applied voltage compared to the same brightness. 3 and 4 show comparison results of current density values and luminance values under the same applied voltage.

Example  2

Anode cut corning 15Ω / m ² (1200Å) ITO glass substrate into 50mm x 50mm x 0.7mm size and ultrasonically clean for 5 minutes in isopropyl alcohol and pure water, and then irradiate with ultraviolet rays for 30 minutes and ozone The glass substrates were installed in a vacuum deposition apparatus after being exposed to the substrate. On the substrate, first, IDE 406, a well-known material well-known as a hole injection layer, was vacuum deposited to form a thickness of 600 Å. Subsequently, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPB) was vacuum-deposited to 300 GPa as a hole transport compound to form a hole transport layer.

After the hole transport layer was formed in this manner, Alq ₃ , a known green fluorescent host, and C545T, a known green fluorescent dopant, were simultaneously deposited at a weight ratio of 98: 2 on the hole transport layer to form a light emitting layer having a thickness of 200 kHz. Subsequently, compound 15 was deposited to a thickness of 300 kV with an electron transport layer, LiF, an alkali metal halide, was deposited to a thickness of 10 kW with an electron injection layer, and Al was vacuum deposited to a thickness of 3000 kV (cathode electrode) on the upper layer of the electron transport layer. An organic light emitting device was manufactured by forming an Al electrode.

The device had a driving voltage of 2.5 V, a current density of 35.11 mA / cm 2, emission luminance of 3286 cd / m 2 at an applied voltage of 6.0 V, a color coordinate of (0.30, 0.64), and an emission efficiency of 9.36 cd / A. The EL emission spectrum of this device is shown in FIG.

As a result of using the compound 15 according to the present invention as the electron transport layer, the turn-on voltage was reduced by 0.5V, the applied voltage at the same current value was significantly lowered, and the current density was improved due to the improvement of the electron injection and transport ability. As the characteristic was improved, an increase in luminance value of about 2 times at the same applied voltage was confirmed. As a result, it was possible to achieve a low power consumption organic electroluminescent device capable of high brightness with low applied voltage compared to the same brightness. 6 and 7 show results of comparing the current density value and the luminance value under the same applied voltage.

A novel organic light emitting compound having a calixarene derivative having at least two or four or more substituents in a molecule represented by Chemical Formula 1 according to the present invention, and is used as a host of green, red and blue phosphorescent dopants. It is possible to manufacture high brightness organic light emitting devices based on superior current density characteristics compared to existing materials.

The compounds according to the present invention will be effectively used as host materials and charge transport materials suitable for fluorescence and phosphorescent dopants of all colors such as red, green, blue and white based on such excellent electrical properties and high charge transport ability. A low voltage, high brightness, long life organic light emitting device can be provided.

Claims (12)

Carlex arene compounds represented by the formula (1): <Formula 1>

Wherein R ₁ to R ₄ are electron transporting organic groups, which are independently of each other a substituted aryl group of C 5 -C 30 or substituted hetero aryl ring of C 5 -C 30. According to claim 1, wherein R ₁ to R ₄ is a calex arene-based compound, characterized in that the C2-C20 fluorine-substituted aryl group and a heteroaryl group substituted heteroatoms in the C5-C20 ring. The method of claim 1, wherein the compound is a calex arene-based compound, characterized in that the compound represented by the formula (2) or [Formula 2]

Wherein R5 and R6 are hydrogen, methyl group, ethyl group, cyano group, fluorine, methoxy group, ethoxy group, or C2-C6 heterocyclic group, or R5 and R6 are linked to each other to form a C5-C6 carbon ring or C2- Forms a C6 heterocycle. According to claim 1, wherein the compound is a calex arene-based compound, characterized in that the compound represented by the following formula (3): [Formula 3]

In the above formula, R7 and R8 are methyl group, ethyl group, trifluoromethyl group, fluorine, C2-C6 heterocyclic group, or phenyl group. The method of claim 1, wherein the compound is a calex arene-based compound, characterized in that the compound represented by the formula:

A compound of formula 4, A method for preparing a calexarene compound represented by the following Chemical Formula 1, comprising reacting one selected from a boron compound of Formula 5 and a tin compound of Formula 6 below. [Formula 4]

Wherein X is Br, Cl, or I. [Formula 5]

Wherein R5 and R6 are hydrogen, methyl group, ethyl group, cyano group, fluorine, methoxy group, ethoxy group, or C2-C6 heterocyclic group, or R5 and R6 are linked to each other to form a C5-C6 carbon ring or C2- Forms a C6 heterocycle.  [Formula 6]

In the above formula, R7 and R8 are methyl group, ethyl group, trifluoromethyl group, fluorine, C2-C6 heterocyclic group, or phenyl group. <Formula 1>

Wherein R ₁ to R ₄ are electron transporting organic groups, which are independently of each other a substituted aryl group of C 5 -C 30 or substituted hetero aryl ring of C 5 -C 30. The method of claim 6, wherein the compound of Formula 4, Obtaining compound (A) from 1,3,5-trihalobenzene; Obtaining compound (B) from compound (A); Obtaining compound (C) from compound (B); Reacting the compound (B) with the compound (C) to obtain a compound (D); And Method for producing a calex arene-based compound of formula (1) characterized in that it is prepared through the step of obtaining a compound of formula (4) from the compound (D).

Wherein X is Br, Cl, or I. A first electrode; Second electrode; And at least an organic layer between the first electrode and the second electrode, The organic light-emitting device of claim 1, wherein the organic film comprises the calex arene-based compound of any one of claims 1 to 5. The method of claim 8, wherein between the first electrode and the second electrode comprises a light emitting layer and an electron injection layer or an electron transport layer comprising any one of claims 1 to 5 of the Alexa-based compound. Organic light emitting device. The method of claim 8, further comprising at least one layer selected from the group consisting of a hole injection layer, an electron blocking layer, a hole blocking layer, an electron transport layer and an electron injection layer between the first electrode and the second electrode. Organic light emitting device. The device of claim 8, wherein the device comprises a first electrode / hole transport layer / light emitting layer / electron transport layer / second electrode, first electrode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / second electrode or An organic light-emitting device having a structure of one electrode / hole injection layer / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / electron injection layer / second electrode. The organic light emitting device of claim 7, wherein the light emitting layer comprises a phosphorescent or fluorescent dopant including red, green, blue, or white.

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