KR20070017733A - Fluorene derivatives, Organic Electroluminescent Polymer Prepared Therefrom and the Electroluminescent Device Manufactured Using the Same - Google Patents

Abstract

The present invention is to prevent the formation of excimer of the main chain in the 9-position of fluorene and to the organic electro-adhesion molecule polymerized using a fluorene derivative and a monomer introduced therein a substituent capable of emitting light by itself It is about. The present invention also relates to an electroluminescent device made of the organic electroluminescent advertising molecule. In the fluorene derivative of the present invention, a substituent is fused to the 9-position of fluorene, and the organic electroluminescent polymer polymerized using the monomer as a monomer has high solubility, high thermal stability, high purity blue, green and It can be used as a host material such as red.

Light emitting polymer, light emitting device, blue light emission, quantum efficiency, fluorene, fluorenyl

Description

Fluorene derivatives, Organic Electroluminescent Polymer Prepared Therefrom and the Electroluminescent Device Manufactured Using the Same}

1 is a cross-sectional view showing a structure of a general organic electroluminescent device manufactured from a substrate / anode / hole transport layer / light emitting layer / electron transport layer / cathode.

FIG. 2 is a schematic representation of the synthesis mechanism of compounds S8, S9 and S10 prepared according to the preparation of the present invention; FIG.

3 is a schematic view showing the synthesis mechanism of the compounds S6 and S11 prepared according to the preparation of the present invention.

※ Explanation of code about main part of drawing ※

11 substrate 12 anode

13 hole transport layer 14 light emitting layer

15: electron transport layer 16: cathode

The present invention relates to fluorene derivatives, organic electroluminescent molecules polymerized using the same as monomers, and electroluminescent devices prepared therefrom. More specifically, excimers of the main chain at the 9-position of fluorene The present invention relates to a monomer for producing an organic electro-molecule advertisement molecule having properties of excellent thermal stability, light stability, solubility, film formability and high quantum efficiency by fusing large substituents capable of preventing formation and self-luminous. The present invention also relates to an organic electroluminescent molecule prepared by polymerization or copolymerization from the monomer and an electroluminescent device using the same.

Recently, due to the rapid growth of the optical communication and multimedia fields, the development into a highly information society has been accelerated. Accordingly, optoelectronic devices using the conversion of photons to electrons or the conversion of electrons to photons have become the core of the modern information electronics industry. Such semiconductor optoelectronic devices can be broadly classified into electroluminescent devices, light receiving devices, and devices in which they are combined. Until now, most displays are light-receiving, while self-emissive electroluminescence displays are fast responding and self-luminous, so they do not require backlighting and have excellent brightness. It is attracting attention as a display element. Electroluminescent devices are classified into inorganic and organic light emitting devices according to the material for forming the light emitting layer. Organic electroluminescence (EL) is a phenomenon in which when an electric field is applied to an organic material, electrons and holes are transferred from the cathode and the anode, respectively, to be combined within the material, and the energy generated is emitted as light.

1 is a cross-sectional view showing the structure of a general organic electroluminescent device manufactured from a substrate / anode / hole transport layer / light emitting layer / electron transport layer / cathode. In FIG. 1, an anode 12 is formed on the substrate 11. The hole transport layer 13, the light emitting layer 14, the electron transport layer 15, and the cathode 16 are sequentially formed on the anode 12. Here, the hole transport layer 13, the light emitting layer 14, and the electron transport layer 15 are organic thin films made of an organic compound. The driving principle of the organic electroluminescent device of the above structure is as follows:

When a voltage is applied between the anode 12 and the cathode 16, holes injected from the anode 12 are moved to the light emitting layer 14 via the hole transport layer 13. Meanwhile, electrons are injected into the light emitting layer 14 from the cathode 16 via the electron transport layer 15, and carriers are recombined in the light emitting layer 14 to generate excitons. This exciton is changed from the excited state to the ground state, whereby the fluorescent molecules of the light emitting layer emit light to form an image.

The organic electroluminescent device driven on the principle described above is classified into a polymer organic electroluminescent device and a low molecular organic electroluminescent device according to the molecular weight of the material for forming an organic film. In general, when the low molecular weight is used in forming the organic layer, the low molecular weight is easy to purify and almost eliminates impurities, so the light emission characteristics are excellent. However, there is a problem in that spin coating is not possible and heat resistance is poor, thereby deteriorating or recrystallizing by driving heat generated when driving the device. On the other hand, when the polymer is used to form the organic film, the energy level is separated into the conduction band and the electrical appliance diagram by the superposition of the π-electron wave function in the polymer backbone, and the band gap energy corresponding to the energy difference is used. The semiconducting properties of the polymers are determined and full color is possible. Such polymers are called π-conjugated polymers.

Al from Cambridge University, UK. H. After an electroluminescent device using poly (p-phenylenevinylene) (PPV), a polymer having conjugated double bonds, was first published in 1990 by Professor RH Friend Research using organic polymers is being actively conducted. Compared with the low molecular weight polymer, the polymer has excellent heat resistance and can be spin coated to easily increase the size of the display device. By introducing various substituents, polyphenylenevinylene (PPV) derivatives, polythiophene (Pth) derivatives, and the like, which can improve processability and express various colors, have been reported. However, as materials such as polyphenylenevinylene derivatives and polythiophene derivatives, high-efficiency red and green light-emitting polymer materials can be obtained among the three primary colors of light, red, green, and blue. Hard to get

On the other hand, polyphenylene derivatives, polyfluorene derivatives, and the like have been reported as blue light emitting polymer materials. Polyphenylene has high oxidation stability and thermal stability, but has a disadvantage of low luminous efficiency and poor solubility. With respect to the polyfluorene derivatives, the prior art is as follows:

US Pat. No. 6,255,449 discloses 9-substituted-2,7-dihalofluorene compounds, and oligomers and polymers thereof, suitable as light emitting materials, such as light emitting layers or carrier transport layers of light emitting diodes. US Patent Nos. 6,309,763 and 6,605,373 introduce electroluminescent copolymers containing florin groups and amine groups in repeat units. According to the '763 patent, such copolymers are useful as light emitting layers or electrotransport layers of electroluminescent devices.

WO02 / 77060 discloses conjugated polymers containing spirofluorene units. According to the patent, the polymer exhibits improved profile properties as a light emitting material for electronic components such as PLEDs.

As described above, researches using polyfluorene derivatives as blue light emitting polymers are being actively conducted, but the interaction between excitons generated in one molecule and excitons of other molecules adjacent to each other, efficiency improvement, lifetime improvement, etc. I have a problem.

Therefore, in the present invention, as a result of extensive research to solve the above-mentioned problems, the disadvantages of the conventional polyfluorene-based system having high solubility and excellent solubility and minimizing intermolecular interaction are significantly improved. The present invention has developed fluorene derivatives and polymers or copolymers using the same, which are excellent as monomers for producing electroluminescent polymers that can be used as host materials such as blue, green, and red.

Accordingly, an object of the present invention is to minimize the intermolecular interaction, to facilitate energy transfer, to suppress the excimer as much as possible to exhibit excellent luminous efficiency, and can be used as a host material for realizing high efficiency blue, green and red colors. It is to provide a fluorene derivative for producing an organic electro-molecular advertising molecule.

Another object of the present invention is to provide a polymerized or copolymerized organic electroadhesion molecule using the fluorene derivative as a monomer.

Still another object of the present invention is to provide an electroluminescent device manufactured using the organic electroluminescent molecule.

The fluorene derivative which is a monomer for preparing an organic electroadhesive molecule of the present invention for achieving the object of the present invention is represented by the following formula (1).

Wherein R ₁ , R ₂ , R ₃ and R ₄ are the same as or different from each other, hydrogen; A linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms;

Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , and Ar ₆ are the same as or different from each other, hydrogen; An aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; Linear or branched alkyl or alkoxy groups having 1 to 20 carbon atoms having at least one hetero atom selected from the group consisting of F, S, N, O, P and Si; Aryl group substituted with at least one substituent selected from the group consisting of a straight or branched chain alkyl group having 1 to 20 carbon atoms and an alkoxy group having at least one hetero atom selected from the group consisting of F, S, N, O, P and Si ; An aryl group having 2 to 24 carbon atoms which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; C 2 substituted with at least one substituent selected from the group consisting of a straight or branched chain alkyl group having 1 to 20 carbon atoms and an alkoxy group having at least one hetero atom selected from the group consisting of F, S, N, O, P and Si An aryl group having a heterocycle of ˜24; A C3 to C40 substituted or unsubstituted trialkylsilyl group; C3-C40 substituted or unsubstituted arylsilyl group; C12-C60 substituted or unsubstituted carbazole group; C6-C60 substituted or unsubstituted phenothiazine group; Or a C 6 -C 60 substituted or unsubstituted arylamine group; And

, 또는

임.X ₁ and X ₂ are the same as or different from each other, and Cl, Br, I, B (OH) ₂ ,

, or

being.

The organic electroadhesion molecule polymerized or copolymerized using the fluorene derivative for achieving another object of the present invention is represented by the following formula (2).

Wherein R ₁ , R ₂ , R ₃ , R ₄ , Ar 1, Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , and Ar ₆ are the same as above; Ar ₇ is selected from the group consisting of C6-C60 substituted or unsubstituted aromatic compounds, C2-C60 substituted or unsubstituted heteroaromatic compounds, and combinations thereof; And

L is an integer of 1 to 1,000,

m is an integer of 1 to 1,000, and

n is an integer of 1-1,000.

The organic electroluminescent device for achieving another object of the present invention is formed between at least one layer comprising an organic electroluminescent molecule represented by the formula (2) between the anode and the cathode, the layer is a hole transport layer, light emitting layer, electron It is characterized in that it is a transport layer or a hole blocking layer.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

As described above, the present invention is a fluorene derivative having a large substituent capable of preventing the excimer formation of the main chain in the fluorine 9-position and capable of emitting light by itself, using the monomer The present invention relates to a polymerized or copolymerized organic electroluminescent molecule, and is intended to be used as a light emitting layer positioned between a pair of electrodes in an electroluminescent device.

Specifically, in the present invention, a novel fluorene derivative in which a substituent is fused to the 9-position, which has a high luminous efficiency and excellent solubility and minimizes intermolecular interactions, significantly improves the performance of existing light emitting polymers, Provided is an organic electroluminescent molecule polymerized and copolymerized using the same and an electroluminescent device prepared therefrom.

According to the present invention, it is possible to prevent the formation of the excimer of the main chain and to introduce a large substituent capable of self luminescence at the 9-position of fluorene to improve the luminous efficiency, as well as the effect of intermolecular excitation by the substituents. Since the excimer is maximally suppressed, one of the biggest problems of polyfluorenes is that it suppresses the formation of aggregation and / or excimer extremely. It is possible. Intramolecular or intermolecular energy transfer is possible with long-chain substituents in the main chain, and the large 9-position substituent of fluorene used in the main chain prevents excimers and greatly reduces nonradiative decay. Since it plays a role, it is possible to exhibit high efficiency luminous characteristics. Therefore, the organic electroluminescent polymer using the monomer of the present invention and the organic electroluminescent device using the same have excellent color purity and high efficiency.

Fluorene derivatives according to the present invention are represented by the following formula (1).

Formula 1

Wherein R ₁ , R ₂ , R ₃ and R ₄ are the same as or different from each other, hydrogen; A linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms;

Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , and Ar ₆ are the same as or different from each other, hydrogen; An aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; Linear or branched alkyl or alkoxy groups having 1 to 20 carbon atoms having at least one hetero atom selected from the group consisting of F, S, N, O, P and Si; An aryl group substituted with at least one substituent selected from the group consisting of a straight or branched chain alkyl group having 1 to 20 carbon atoms and an alkoxy group having at least one hetero atom selected from the group consisting of F, S, N, O, P and Si ; An aryl group having 2 to 24 carbon atoms which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; C 2 substituted with at least one substituent selected from the group consisting of a straight or branched chain alkyl group having 1 to 20 carbon atoms and an alkoxy group having at least one hetero atom selected from the group consisting of F, S, N, O, P and Si An aryl group having a heterocycle of ˜24; A C3 to C40 substituted or unsubstituted trialkylsilyl group; C3-C40 substituted or unsubstituted arylsilyl group; C12-C60 substituted or unsubstituted carbazole group; C6-C60 substituted or unsubstituted phenothiazine group; Or a C 6 -C 60 substituted or unsubstituted arylamine group; And

, 또는

이다.X ₁ and X ₂ are the same as or different from each other, and Cl, Br, I, B (OH) ₂ ,

, or

to be.

The fluorene derivative may be synthesized through an alkylation reaction, bromination reaction, Grignard reaction, or Wittig reaction, which is commonly used in the art, but the method is accompanied. In this regard, specific synthetic mechanisms are shown in FIGS. 2 and 3 and are described in detail in the preparation examples below. However, the present invention is not necessarily limited to these specific examples.

Preferably, in Formula 1, R ₁ , R ₂ , R ₃ and R ₄ may be selected from the following compounds, each the same or different.

Hydrogen,

Preferably, Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , and Ar ₆ may be each selected from the following compounds, the same as or different from each other.

R ₅ to R ₂₇ are the same as or different from each other, hydrogen, a linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms. Preferably, R ₅ to R ₂₇ may be selected from the following compounds, each the same or different.

Hydrogen,

The organic electroadhesion molecule polymerized or copolymerized with the fluorene derivative represented by Chemical Formula 1 of the present invention is represented by the following Chemical Formula 2.

Formula 2

Wherein R ₁ , R ₂ , R ₃ , R ₄ , Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , and Ar ₆ are the same as above;

Ar7 is selected from the group consisting of C6-C60 substituted or unsubstituted aromatic compounds, C2-C60 substituted or unsubstituted heteroaromatic compounds, and combinations thereof; And

L is an integer of 1 to 1,000,

m is an integer of 1 to 1,000, and

n is an integer of 1-1,000.

As the polymerization or copolymerization method of the organic electroluminescent polymer represented by Chemical Formula 2, any method known in the art may be adopted, and preferably a CC such as a Yamamoto coupling reaction or a Suzuki coupling reaction. It can be carried out through a coupling reaction.

In addition, in the present invention, other residues may be selectively included in addition to the specific fluorene derivative represented by Chemical Formula 1, and are represented by Ar ₇ in Chemical Formula 2. That is, Ar ₇ is a component copolymerized with the monomer represented by Formula 1, in which the ratio of L: m in Formula 2 is in the range of 1: 100 to 100: 1, more preferably 5: 100 to 100: 5. Is introduced to be.

Representative examples of the Ar ₇ component are as follows:

(Iii) a C6 to C60 substituted or unsubstituted arylene group;

(Ii) a C2 to C60 substituted or unsubstituted heterocyclic arylene group wherein at least one hetero atom selected from the group consisting of N, S, O, P and Si is included in the aromatic ring;

(Iii) a C 6 to C 60 substituted or unsubstituted arylenevinylene group;

(Iii) a C6-C60 substituted or unsubstituted arylamine group;

(Iii) a C12-C60 substituted or unsubstituted carbazole group; And

(Iii) selected from the group consisting of combinations thereof

Here, Ar ₇ is a straight or branched chain alkyl or alkoxy group having 1 to 20 carbon atoms; An aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; Cyano group (-CN); Or a substituent such as a silyl group.

More specifically,

(Iii) when Ar ₇ is a phenylene group or a fluorenyl group among the substituted or unsubstituted arylene groups of C6 to C60, representative examples of such compounds are as follows, and may be selected from:

(Ii) where Ar ₇ is a C2-C60 substituted or unsubstituted heterocyclic arylene group, representative examples of such compounds are as follows and may be selected from:

(Iii) where Ar ₇ is a C6 to C60 substituted or unsubstituted arylenevinylene group, representative examples of such compounds are as follows, and may be selected from:

(Iii) when Ar ₇ is a C6-C60 substituted or unsubstituted arylamine group, representative examples of such compounds are as follows, and may be selected from

Wherein R ₂₈ , R ₂₉ and R ₃₀ are each the same as or different from each other, hydrogen; Linear or branched alkyl or alkoxy groups having 1 to 20 carbon atoms; Or an aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a straight or branched chain alkyl group having 1 to 20 carbon atoms and an alkoxy group, and more specifically, may be selected from the following compounds:

And,

(Iii) when Ar ₇ is a substituted or unsubstituted carbazole group of C ₁₂ to C 60, representative examples of such compounds are as follows and may be selected from them;

In the formula, R ₃₁ represents a straight or branched chain alkyl group or alkoxy group having 1 to 20 carbon atoms; Or an aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group.

In addition, when Ar ₇ is a (i) C ₆ to C 60 substituted or unsubstituted arylamine group, they may be contained in an amount of about 5 mol% to 15 mol% in the light emitting polymer.

The number average molecular weight (Mn) of the light emitting polymer obtained as described above is about 5,000 to 1,000,000, preferably 10,000 to 300,000, and the molecular weight distribution is 1 to 10, more preferably 1.5 to 5.

The organic electro-adhesive molecules according to the present invention described above have excellent thermal stability, oxidative stability and solubility, minimize intermolecular interactions, facilitate energy transfer, suppress vibration modes as much as possible, and exhibit blue, green and It can be applied as a red light emitting host.

According to the present invention, the organic electroluminescent molecule is used as a material for forming a light emitting layer, a hole transport layer, an electron transport layer or a hole blocking layer positioned between a pair of electrodes in the electroluminescent device.

The organic electroluminescent device of the present invention may be configured to further include a hole transport layer and an electron transport layer as well as the most common device configuration of the anode / light emitting layer / cathode.

1 is a cross-sectional view illustrating a structure of a general organic electroluminescent device composed of a substrate / anode / hole transport layer / light emitting layer / electron transport layer / cathode. Referring to this, an example of an organic electroluminescent device to which the organic electroluminescent molecule of the present invention is applied is as follows. It can be prepared as follows.

First, a material for the anode 12 electrode is coated on the substrate 11.

Here, the substrate 11 is a substrate used in a conventional organic electroluminescent device, preferably a glass substrate or a transparent plastic substrate excellent in transparency, surface smoothness, ease of handling and waterproof.

In addition, as the material for the anode 12 electrode, indium tin oxide (ITO), tin oxide (SnO ₂ ), zinc oxide (ZnO), or the like, which is transparent and has excellent conductivity, may be used.

Next, the hole transport layer 13 may be formed by vacuum deposition or sputtering on the anode 11 electrode, and the light emitting layer 14 may be formed through a solution coating method such as spin coating or inkjet printing. In addition, the electron transport layer 15 is formed on the light emitting layer 14 before the cathode 16 is formed. At this time, the thickness of the light emitting layer 14 is preferably 5nm ~ 1㎛, preferably 10 ~ 500nm, the thickness of the hole transport layer and the electron transport layer is preferably 10 ~ 10,0001.

According to the present invention, a material for forming an electron transport layer may be used for the electron transport layer 15, or the compound represented by Chemical Formula 1 may be formed by vacuum deposition, sputtering, spin coating, or inkjet printing.

The hole transport layer 13 and the electron transport layer 15 serves to increase the probability of light emitting coupling in the light emitting polymer by efficiently transporting the carriers to the light emitting polymer. The material for forming the hole transport layer 13 and the electron transport layer 15 usable in the present invention is not particularly limited, but preferably, the material for the hole transport layer 13 is doped with a poly (styrenesulphonic acid) (PSS) layer. PEDOT: PSS, N, N'-bis (3-methylphenyl) -N, N-diphenyl- [1,1'-biphenyl]-which is poly (3,4-ethylenedioxy-thiophene) (PEDOT)- 4,4'-diamine (TPD) is preferred, and as the electron transport layer material, aluminum trihydroxyquinoline (Alq3), 1,3,4-oxadiazole derivative PBD (2- (4-biphenylyl)- 5-phenyl-1,3,4-oxadiazole, quinoxaline derivative TPQ (1,3,4-tris [(3-penyl-6-trifluoromethyl) quinoxaline-2-yl] benzene) and triazole derivatives are preferred. .

On the other hand, when the organic electro-adhesive molecule according to the present invention to form a layer through the solution coating method, by blending with polymers having conjugated double bonds, such as other fluorene-based polymers, polyphenylene vinylene-based, polyparaphenylene-based In some cases, binder resins may be mixed and used. Examples of the binder resins include polyvinylcarbazole, polycarbonate, polyester, polyarylate, polystyrene, acrylic polymer, methacryl polymer, polybutyral, polyvinyl acetal, diallyl phthalate polymer, phenol resin, epoxy resin, Silicone resins, polysulfone resins or urea resins, and the like, which may be used individually or in combination.

Optionally, a hole-blocking layer, such as lithium fluoride (LiF), is further formed by vacuum deposition or the like to limit the transfer rate of holes in the light-emitting layer 14 and to bond electron-holes. You can increase the probability.

Finally, a material for the cathode 16 electrode is coated on the electron transport layer 15. As the cathode forming metal, lithium (Li), magnesium (Mg), calcium (Ca), aluminum (Al), Al: Li, and the like having a small work function are used.

The organic electroluminescent device according to the present invention may be manufactured in the order as described above, namely anode / hole transport layer / light emitting layer / electron transport layer / cathode, and vice versa, that is, cathode / electron transport layer / light emitting layer / hole transport layer / anode You may manufacture in order.

In addition, the organic electroluminescent molecules according to the present invention can be used not only as a polymer organic electroluminescent device but also as a photoconversion material in a photodiode or a semiconductor material in a polymer TFT (Thin Film Transistor).

As described above, the organic electro-adhesive molecule according to the present invention has not only the effect of improving the luminous efficiency by introducing a large substituent at the 9-position of fluorene used as the main chain, but also the property of inhibiting the intermolecular excimer by the substituent as much as possible. This expression suppresses the formation of aggregation and / or excimer, which is one of the biggest problems of the polyfluorene system. In addition, not only the intra- and intermolecular energy transfer is possible with substituents having a long wavelength in the main chain, but also the 9-position of the fluorene group used as the main chain prevents the excimer from being substituted by a large substituent, thereby greatly reducing non-radiative attenuation. It has high efficiency luminous characteristics. Therefore, fluorene derivatives for the production of organic electroluminescent molecules of the present invention, organic electroluminescent molecules polymerized and copolymerized using the same, and organic electroluminescent devices prepared therefrom exhibit excellent color purity, brightness and high efficiency characteristics.

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

In the following Examples and Comparative Examples, the compounds referred to as S1 to S11 are each represented by the following structural formula as monomers for the preparation of the organic advertised molecules of the present invention.

       Preparation Examples 1 to 3 were carried out according to the reaction mechanism shown in FIG.

Preparation Example 1

Preparation of Monomer S8

A) Synthesis of M1-1

20 g of 2,7-dibromofluorenone and 96 g of o-cresol are dissolved in 300 ml of methylene chloride, and 11.4 g of methanesulfonic acid is slowly injected at 0 ° C, followed by reaction for 3 hours. After completion of the reaction, unreacted o-cresol was removed by vacuum distillation and washed several times with hexane to obtain 25 g of M1-1.

B) Synthesis of M1-2

After dissolving 25 g of M1-1 in 300 ml of DMSO (dimethylsulfoxide) and injecting 20 g of KOH, 50 g of bromooctane was injected and reacted for 6 hours. After completion of the reaction, 400 ml of distilled water was added, extracted with hexane, and washed with distilled water. After extraction, 23 g of M1-2 was obtained using column chromatography.

C) Synthesis of M1-3

Dissolve 23 g of M1-2 in 300 ml of benzene and raise the temperature to the boiling point of benzene. 11 g of N-bromosuccimide (NBS) and 0.5 g of BPO (benzoperoxide) are rapidly injected while boiling in benzene and the reaction proceeds for 3 hours. After the reaction was completed, the temperature was lowered to room temperature, 400 ml of hexane was added, and 22 g of a mixture containing M1-3 was obtained through column chromatography.

D) Synthesis of M1-4

10 g of triethyl phosphite was injected into 22 g of the M1-3 mixture, and the temperature was raised to 100 ° C. for 12 hours. After completion of the reaction, unreacted triethyl phosphite was removed by vacuum distillation.

E) Synthesis of M1-6

After dissolving 50 g of 2-methoxyphenol in 300 ml of DMF (demethylformamide), NBS dissolved in DMF was slowly injected while maintaining the reactor temperature at 0 ° C. After the reaction for 12 hours, the product was added to 1 liter of distilled water and extracted with chloroform to obtain 4-bromo-2-methoxyphenol (4-bromo-2-methoxyphenol). 40 g of 4-bromo-2-methoxyphenol and 140 g of KOH were injected into 400 mL of DMSO, and bromohexane was slowly injected at room temperature, followed by reaction for 12 hours. After the reaction was completed, the reactant was added to 2 liters of distilled water, extracted using MC (Methylene chloride), and M1-6 '35g was obtained by using column chromatography with MC and hexane. After dissolving 20 g of M1-6 'in 400 ml of THF (Tetrahydrofuran), 1 equivalent of n-BuLi was injected and reacted for 1 hour while maintaining the reactor temperature at -78 ° C. After the reaction, 27 ml of DMF was slowly injected at -78 ° C and reacted for 3 hours. After completion of the reaction, THF was removed, extracted with chloroform, and column chromatography was used to obtain 10 g of M1-6.

F) synthesis of S8

After dissolving 7.0 g of M1-4 and 3.4 g of M1-6 in 300 ml of THF, 3.4 g of tBuOK was injected and reacted at room temperature for 8 hours. After completion of the reaction, the mixture was neutralized with 2N HCl aqueous solution, extracted with methylene chloride, and 4.2 g of S10 was obtained using column chromatography.

Preparation Example 2

Synthesis of Monomer S9

A) Synthesis of M1-7

POCl ₃ was slowly injected into 50 mL of DMF at 0 ° C. and stirred for 3 hours. 50 ml of DMF and 20 g of triphenylamine were injected and reacted at 80 ° C. for 6 hours, and then the reaction was poured into NaHCO ₃ aqueous solution and stirred for 1 hour. Extraction with methylene chloride and recrystallization with methylene chloride and ethanol gave 18 g of the compound represented by M1-7.

B) Synthesis of S9

After dissolving 6.2 g of M1-4 and 3.5 g of M1-7 in 300 ml of THF, 3.2 g of tBuOK was injected and reacted at room temperature for 8 hours. After completion of the reaction, neutralized with 2N HCl aqueous solution, extracted with methylene chloride and obtained 4.5g of S9 by column chromatography.

Preparation Example 3

Synthesis of Monomer S10

A) Synthesis of M1-5

After 30ml of DMF was injected into the reactor and 9ml of POCl ₃ was slowly injected while maintaining the temperature at 0 ° C, the reaction was performed for 2 hours, and then 20g of N-hexylcarbazole was added to 50ml of DMF 50ml. It was dissolved in the reactor was injected and the temperature was maintained at 80 ℃ to react for 6 hours. After completion of the reaction, the product was put into iced water, neutralized with NaOH aqueous solution, and extracted with EA (Ethyl Acetate). After extraction, 15 g of M1-5 was obtained using column chromatography.

B) synthesis of S10

After dissolving 5.5 g of M1-4 and 3.5 g of M1-5 in 300 ml of THF, 2.8 g of tBuOK was injected and reacted at room temperature for 8 hours. After completion of the reaction, neutralized with 2N HCl aqueous solution, extracted with methylene chloride and 4.2g of S10 by column chromatography.

Preparation Example 4 and Preparation Example 5 were synthesized according to the reaction mechanism of FIG. 3.

Preparation Example 4

Synthesis of Monomer S6

A) Synthesis of M3-1

3.5 g (145 mmol) of Mg was added to a 500 ml three-necked flask, and 60 g (145 mmol) of 9,9-dihexyl-2-bromofluorene was dissolved in 300 ml of THF to slowly add dropwise Grignard reagent. . The bath temperature was lowered to 0 ° C. or lower, and then 39 g (102 mmol) of 2,7-dibromofluorenone was added under a nitrogen stream, and the temperature was gradually raised to room temperature, followed by stirring for 10 hours. The reaction is poured into water, the organic layer is separated and the solvent is blown on a rotary evaporator. 65 g (97 mmol, 83%) of compound (9- (9 ', 9'-dihexylfluorene-2'-yl) -2,7-dibromofluorene-9-ol separated by column chromatography) ) (M3-1).

B) Synthesis of S6

45 g (67 mmol) of the compound M3-1 and 67 g (200 mmol) of 9 ', 9'-dihexylfluorene were dissolved in 500 ml of dichloromethane, and the temperature was lowered to 0 ° C. and stirred in a round flask. A solution of 7.5 g (78 mmol) of methanesulfonic acid dissolved in 100 ml of dichloromethane was slowly injected, followed by stirring for 2 hours. The reaction is poured into water and extracted with methylene chloride, then the solvent is blown on a rotary evaporator. Separation by column chromatography was performed to obtain 33 g (33 mmol, 50 g) of compound 2,7-dibromo-9,9-di- (9 ', 9'-dihexylfluorene-2'-yl) fluorene (S6). %) Obtained.

Preparation Example 5

Synthesis of Monomer S11

A) Synthesis of M3-2

In a 500 ml round flask, 20 g (91 mmol) of compound catechol and 107 g (436 mmol) of 2-methyl butyl p-toluenesulfonate were dissolved in 200 ml of DMSO. , 53 g (473 mmol) of potassium-t-butoxide (t-BuOK) was added slowly, followed by reaction at 70 ° C. for 12 hours. The reaction was poured into 500 ml of water, extracted with methylene chloride, the solvent was removed with a rotary evaporator, separated by column chromatography using a mixed solvent of hexane and ethyl acetate, and then 1,2-di (2-methyl). 3 g (148 mmol, 81%) of butyloxy benzene (1,2-di (2-methyl) butyloxy benzene; M3-2) were obtained.

B) synthesis of S11

In a round flask of 2 ??, 45 g (67 mmol) of compounds M3-1 and 22.6 g (90 mmol) of M3-2 were dissolved in 500 ml of dichloromethane, and then the temperature was lowered to 0 ° C. A solution of 7.5 g (78 mmol) of phenolic acid (methanesulfonic acid) dissolved in 100 ml of dichloromethane was slowly added thereto, followed by stirring for 2 hours. The reaction was poured into water, extracted with methylene chloride, the solvent was removed by rotary evaporator and separated using column chromatography. As a result, compound 2,7-dibromo-9- (9 ', 9'-dihexylfluorene-2'-yl) -9- (3 ", 4" -di (2 "-methyl) butyloxy Phenyl) fluorine (2,7-dibromo-9- (9 ', 9'-dihexylfluoren-2'-yl) -9- (3 ", 4" -di (2 "-methyl) butyloxyphenyl) fluorine; S11) 57 g (63 mmol, 94%) was obtained.

Comparative Example 1

In a 50 ml Schlenk flask, Compound S1 0.89 mmol, Compound S2 0.87 mmol, Compound S3 0.21 mmol Compound S4 0.10 mmol, Compound S5 0.06 mmol, dissolved in 16.4 ml of toluene degassed with nitrogen, and then stored under nitrogen. 4.35 mmol of Ni (COD) ₂ , 4.35 mmol of 1.4-cyclooctadiene (COD), and 4.35 mmol of dipyridyl were added to a Schlenk flask under nitrogen, 8.2 ml of toluene degassed with nitrogen, and 8.2 ml of DMF. Then stirred at 80 ° C. for 30 minutes. It was added to the reaction vessel, and polymerization was performed for 24 hours. After the polymerization, the reaction solution was added to 300 ml of hydrochloric acid (35 w%): acetone: ethanol = 1: 1: 1 solution to remove the unreacted catalyst and precipitate the polymer. After filtering the polymer was dissolved in chloroform and filtered again with celite to remove the residual catalyst, concentrated and reprecipitated in methanol and dried (Mw = 94,000, Mn = 40,700 PDI (polydispersity) = 2.31).

Example 1

Into a 50 ml Schlenk flask, Compound S1 0.80 mmol, Compound S2 0.80 mmol, Compound S3 0.21 mmol Compound S4 0.10 mmol, Compound S5 0.06 mmol, and Compound S8 0.14 mmol, were dissolved in 16.4 ml of toluene degassed with nitrogen, and then nitrogen. Stored under. 4.35 mmol of Ni (COD) 2, 4.35 mmol of 1.4-cyclooctadiene (COD), and 4.35 mmol of dipyridyl were added to the Schlenk flask under nitrogen, 8.2 ml of toluene degassed with nitrogen, and 8.2 ml of DMF. Then stirred at 80 ° C. for 30 minutes. The monomer solution was added to the reaction vessel together with the catalyst, and polymerization was performed for 24 hours. After the polymerization, the reaction solution was added to 300 ml of hydrochloric acid (35 w%): acetone: ethanol = 1: 1: 1 solution to remove the unreacted catalyst and precipitate the polymer. After filtering the polymer was dissolved in chloroform and filtered again with celite to remove the residual catalyst, concentrated and reprecipitated in methanol and dried (Mw = 106,000, Mn = 51,000, PDI = 2.08).

Example 2

Into a 50 ml Schlenk flask, Compound S1 0.80 mmol, Compound S2 0.80 mmol, Compound S3 0.21 mmol Compound S4 0.10 mmol, Compound S5 0.06 mmol, and Compound S9 0.14 mmol, dissolved in 16.8 ml of degassed toluene with nitrogen, and then nitrogen. Stored under. As a catalyst, 4.25 mmol of Ni (COD) _2, 4.25 mmol of 1.4-cyclooctadiene (COD), and 4.25 mmol of dipyridyl were added to a Schlenk flask under nitrogen, 8.4 ml of toluene degassed with nitrogen, and 8.4 ml of DMF. Then stirred at 80 ° C. for 30 minutes. The monomer solution was added to the reaction vessel together with the catalyst, and polymerization was performed for 24 hours. After the polymerization, the reaction solution was added to 300 ml of hydrochloric acid (35w%): acetone: ethanol = 1: 1: 1 solution to remove the unreacted catalyst and precipitate the polymer. After filtering the polymer was dissolved in chloroform and filtered again with celite to remove the residual catalyst, concentrated and reprecipitated in methanol and dried (Mw = 89,400, Mn = 37,400, PDI = 2.39).

Example 3

In a 50 ml Schlenk flask, compound S3 0.067 mmol, compound S5 0.027 mmol, compound S6 0.526 mmol, compound S7 0.034 mmol, and compound S9 0.0472 mmol were dissolved in 6.9 ml of toluene degassed with nitrogen, and then stored under nitrogen. As a catalyst, 1.416 mmol of Ni (COD) 2, 1.416 mmol of 1.4-cyclooctadiene (COD), and 1.416 mmol of dipyridyl were added to a Schlenk flask under nitrogen, 3.4 ml of toluene degassed with nitrogen, and 3.4 ml of DMF. Then stirred at 80 ° C. for 30 minutes. The monomer solution was added to the reaction vessel together with the catalyst, and polymerization was performed for 24 hours. After the polymerization was completed, the reaction solution was added to 300 ml of hydrochloric acid (35w%): acetone: ethanol = 1: 1: 1 solution to remove the unreacted catalyst and precipitate the polymer. After filtering the polymer was dissolved in chloroform and filtered again with celite to remove the residual catalyst, concentrated and reprecipitated in methanol and dried (Mw = 50,700, Mn = 24,100, PDI = 2.1).

Example 4

Into a 50 ml Schlenk flask, compound S2 0.220 mmol, compound S3 0.063 mmol, compound S5 0.025 mmol, compound S6 0.220 mmol, compound S7 0.032 mmol, and compound S9 0.094 mmol were dissolved in 5.5 ml of toluene degassed with nitrogen. Stored under nitrogen. As a catalyst, 1.32 mmol of Ni (COD) _2, 1.32 mmol of 1.4-cyclooctadiene (COD), and 1.32 mmol of dipyridyl were added to a Schlenk flask under nitrogen, 2.8 ml of toluene degassed with nitrogen, and 2.8 ml of DMF. Then stirred at 80 ° C. for 30 minutes. The monomer solution and the catalyst were added to the reaction vessel, and polymerization was performed for 24 hours. After the polymerization, the reaction solution was added to 300 ml of hydrochloric acid (35w%): acetone: ethanol = 1: 1: 1 solution to remove the unreacted catalyst and precipitate the polymer. After filtering the polymer was dissolved in chloroform and filtered again with celite to remove the residual catalyst, concentrated and reprecipitated in methanol and dried (Mw = 61,200, Mn = 27,800, PDI = 2.2).

Example 5

Manufacture of Electroluminescent Device

Baytron AI4083 (HC Stark Co., Ltd.) was spin-coated at 2000 rpm on the top of the patterned ITO substrate, dried at 100 ° C. for 5 minutes, and the polymers polymerized in Comparative Examples and Examples were coated with a solution dissolved in 0.5 to 2 wt% toluene. A light emitting layer having a thickness of 1000 mW was formed. LiF 20 kV was vacuum-deposited on the emission layer and Al 1000 kV was vacuum-deposited to manufacture an organic electroluminescent device. The characteristics of the organic electroluminescent device thus manufactured were tested and the results are shown in Table 1 below.

Start voltage Maximum Efficiency (Cd / A) Color coordinates (x, y) External quantum efficiency (%) Comparative Example 1 6.2 V 0.36 0.18, 0.21 0.24 Example 1 5.0 V 0.42 0.17, 0.19 0.30 Example 2 5.0 V 0.41 0.16, 0.15 0.35 Example 3 5.4 V 1.31 0.16, 0.14 1.33 Example 4 4.8 V 0.81 0.17, 0.16 1.20

As shown in Table 1, compared with the polymer Comparative Example 1 using the monomers S1, S2, S3, S4, and S5 Examples 1 to 4 used the monomers S6, S8, S9 according to the present invention. Example 1 further polymerized by injecting S8 showed an effect of improving the external quantum efficiency as well as color coordinates. The excimer formation is prevented by the S8 substituents, and the color coordinate improvement effect is considered to be a phenomenon due to the energy transfer.

In addition, Example 2 using S9 also showed better performance in color coordinates and efficiency than Comparative Example 1 due to the similar effect to Example 1 and showed better color coordinates and external quantum efficiency than Example 1.

In the case of Example 3, S6 was used in place of S1, but the efficiency improvement effect was better than that of Example 2, which shows that S6 is superior to S1 as the host material of the blue polymer. In Example 4, a certain amount of S6 was replaced with S2, and this result also shows that S6 is a superior host material than S2.

Through the above results, we developed light-emitting polymers with excellent efficiency and color purity by using monomers with excimer prevention and energy transfer properties. In addition, we developed light-emitting polymers with improved color purity and efficiency by applying excellent host monomer. It was.

As described above, the electroadhesion molecule polymerized using a fluorene derivative having a large substituent capable of preventing the excimer formation of the main chain and self-emitting at the 9-position of the present invention as a monomer. Has excellent thermal stability and high luminous efficiency, solubility and minimization of intermolecular interaction, and improves the disadvantages of polyfluorene system such as low luminous efficiency and solubility. It is expected to be used as a host material such as to exhibit excellent light emission characteristics.

Claims (7)

Fluorene derivatives characterized in that represented by the following formula (1) in which a substituent is introduced at the 9-position of fluorene; Formula 1

Wherein R ₁ , R ₂ , R ₃ and R ₄ are the same as or different from each other, hydrogen; A linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms; Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , and Ar ₆ are the same as or different from each other, hydrogen; An aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; Linear or branched alkyl or alkoxy groups having 1 to 20 carbon atoms having at least one hetero atom selected from the group consisting of F, S, N, O, P and Si; An aryl group substituted with at least one substituent selected from the group consisting of a straight or branched chain alkyl group having 1 to 20 carbon atoms and an alkoxy group having at least one hetero atom selected from the group consisting of F, S, N, O, P and Si ; An aryl group having 2 to 24 carbon atoms which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; C 2 substituted with at least one substituent selected from the group consisting of a straight or branched chain alkyl group having 1 to 20 carbon atoms and an alkoxy group having at least one hetero atom selected from the group consisting of F, S, N, O, P and Si An aryl group having a heterocycle of ˜24; A C3 to C40 substituted or unsubstituted trialkylsilyl group; C3-C40 substituted or unsubstituted arylsilyl group; C12-C60 substituted or unsubstituted carbazole group; C6-C60 substituted or unsubstituted phenothiazine group; Or a C 6 -C 60 substituted or unsubstituted arylamine group; And X ₁ and X ₂ are each independently Cl, Br, I, B (OH) ₂ ,

, or

being. Organic electro-adhesive molecule comprising the fluorene derivative according to claim 1, characterized in that represented by the formula (2); Formula 2

Wherein R ₁ , R ₂ , R ₃ and R ₄ are the same as or different from each other, hydrogen; A linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms; Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , and Ar ₆ are the same as or different from each other, hydrogen; An aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; Linear or branched alkyl or alkoxy groups having 1 to 20 carbon atoms having at least one hetero atom selected from the group consisting of F, S, N, O, P and Si; An aryl group substituted with at least one substituent selected from the group consisting of a straight or branched chain alkyl group having 1 to 20 carbon atoms and an alkoxy group having at least one hetero atom selected from the group consisting of F, S, N, O, P and Si ; An aryl group having 2 to 24 carbon atoms which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; Carbon number substituted with at least one substituent selected from the group consisting of a straight or branched chain alkyl group having 1 to 20 carbon atoms and an alkoxy group having at least one hetero atom selected from the group consisting of F, S, N, O, P and Si Aryl groups having 2 to 24 heterocycles; A C3 to C40 substituted or unsubstituted trialkylsilyl group; C3-C40 substituted or unsubstituted arylsilyl group; C12-C60 substituted or unsubstituted carbazole group; C6-C60 substituted or unsubstituted phenothiazine group; Or a C 6 -C 60 substituted or unsubstituted arylamine group; Ar ₇ is selected from the group consisting of C6-C60 substituted or unsubstituted aromatic compounds, C2-C60 substituted or unsubstituted heteroaromatic compounds, and combinations thereof; And, L is an integer of 1 to 1,000, m is an integer of 1 to 1,000, and n is an integer of 1-1,000. The method according to claim 2, wherein Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar5, and Ar ₆ are the same as or different from each other organic electro-adhesive molecule, characterized in that selected from the following compounds;

R ₅ to R ₂₇ are the same as or different from each other, hydrogen, a linear or branched alkyl group or alkoxy group having 1 to 20 carbon atoms. The compound of claim 2, wherein Ar ₇ is: (Iii) a C6 to C60 substituted or unsubstituted arylene group; (Ii) a C2 to C60 substituted or unsubstituted heterocyclic arylene group wherein at least one hetero atom selected from the group consisting of N, S, O, P and Si is included in the aromatic ring; (Iii) a C 6 to C 60 substituted or unsubstituted arylenevinylene group; (Iii) a C6-C60 substituted or unsubstituted arylamine group; (Iii) a C12-C60 substituted or unsubstituted carbazole group; And (Iii) selected from the group consisting of combinations thereof Here, the substituent of Ar may be a linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms; An aryl group which is unsubstituted or substituted with at least one substituent selected from the group consisting of a linear or branched alkyl group having 1 to 20 carbon atoms and an alkoxy group; Cyano group (-CN); And silyl groups. Organic electro-adhesive molecules, characterized in that selected from the group consisting of. The method of claim 2, wherein the organic electroluminescent advertising molecule is an organic electroluminescent advertising molecule, characterized in that the number average molecular weight is 5,000 to 1000,000, and has a molecular weight distribution of 1 to 10. An organic electroluminescent device comprising at least one layer comprising an organic electroluminescent advertising molecule according to claim 2 between an anode and a cathode, wherein said layer is a major transport layer, a light emitting layer, an electron transport layer or a hole blocking layer. The organic electroluminescent device according to claim 6, wherein the structure of the electroluminescent device is an anode / light emitting layer / cathode, an anode / hole transporting layer / light emitting layer / cathode, or an anode / hole transporting layer / light emitting layer / electron transporting layer / cathode.

Images