KR100604196B1 - Polyspirobifluorenyl-2,7-vinylene and Polydialkylfluorenyl-2,7-vinylene Derivatives Having High Thermal Stability, Luminescence Property and Light Emitting Diodes Using the Same - Google Patents

Abstract

The present invention is poly (spirobifluorenyl-2,7-vinylene), (Spiro-PFV, X₂-Spiro-PFV) that can be used in the organic electroluminescent device And a poly (florenyl-2,7-vinylene) (PFV) derivative and an organic electroluminescent device using the same.

The poly (spirobifluorenyl-2,7-vinylene) -based and poly (alkylflorenyl-2,7-vinylene) derivatives synthesized in the present invention emit light compared to the PPV derivatives used in conventional organic electroluminescent devices. The heat resistance, stability of the electric field, and light emission characteristics of the driving voltage are greatly improved.

Poly (paraphenylenevinylene) (PPV), poly (spirobifluorenyl-2,7-vinylene) (Spiro-PFV, X₂-Spiro-PFV), poly (alkylflorenyl-2,7-vinyl Rennes) (PFV)

Description

Poly (spirobifluorenyl-2,7-vinylene) -based and poly (alkylflorenyl-2,7-vinylene) derivatives having improved thermal stability and luminescence properties and electroluminescent devices using the same {Poly (spirobifluorenyl-2 , 7-vinylene) and Poly (dialkylfluorenyl-2,7-vinylene) Derivatives Having High Thermal Stability, Luminescence Property and Light Emitting Diodes Using the Same}

1 is a cross-sectional view showing the structure of a conventional general organic electroluminescent device.

Figure 2 is a reaction diagram illustrating a monomer manufacturing process of Spiro-PFV derivative according to Example 1 of the present invention.

Figure 3 is a reaction diagram showing a monomer manufacturing process of X₂-Spiro-PFV derivative according to another embodiment 2 of the present invention.

Figure 4 is a reaction diagram showing a monomer manufacturing process of the PFV derivative according to another embodiment 3 of the present invention.

FIG. 5 is a reaction diagram illustrating a polymerization process of monomers synthesized according to Examples 1, 2, and 3 of the present invention. FIG.

6 is an FT-IR graph of the X₂-Spiro-PFV derivative synthesized according to an embodiment of the present invention.

Figure 7 is a graph measuring the UV-visible absorbance of the Spiro-PFV, X₂-Spiro-PFV and PFV derivatives synthesized in the present invention, respectively.

8 is a graph measuring the PL strength of the Spiro-PFV, X₂-Spiro-PFV and PFV derivatives synthesized in the present invention, respectively.

Figure 9 is a graph showing the EL intensity of the electroluminescent device fabricated using the Spiro-PFV, X₂-Spiro-PFV and PFV derivatives synthesized in the present invention, respectively.

10 is a schematic cross-sectional view of an organic electroluminescent device employing Spiro-PFV, X₂-Spiro-PFV and PFV derivatives, which are light emitting polymers prepared according to Examples 4, 5 and 6 of the present invention, as light emitting layers.

11 is a graph showing the current density and the intensity of light emission luminance according to the voltage of the organic electroluminescent device manufactured using the X₂-Spiro-PFV derivative synthesized in the present invention.

12 is a graph showing luminous efficiency versus current density of an electroluminescent device fabricated using the X₂-Spiro-PFV derivative synthesized in the present invention.

13A and 13B are graphs showing EL intensities according to applied voltages of the X 2 -Spiro-PFV and PFV derivatives synthesized in the present invention.

14A and 14B are graphs showing the voltage and current intensity of the electroluminescent device fabricated using the optical spectrum of MEH-PPV and MEH-PPV, respectively, a conventional PPV derivative.

The present invention relates to a light emitting polymer that can be used in an organic electroluminescent device, and more particularly, to poly (spirobifluorenyl-2,7-vinylene) [poly (spirobifluorenyl-2,7-vinylene), (Spiro -PFV, X₂-Spiro-PFV)] and poly (florenyl-2,7-vinylene) (PFV) derivatives and organic electroluminescent device using the same.

Conductive polymers, which have both the electrical and optical properties of semiconductors and metals and the advantages of polymers, have been developed since the 1970s and have been applied to films, fibers, and various fields. In particular, R.H. of Cambridge University, UK. Since the first presentation of organic electroluminescent devices using poly (paraphenylenevinylene) (PPV), a polymer having conjugated double bonds, by the Friend team, various PPV derivatives as materials of organic electroluminescent devices Research is being done on.

Conventionally, an organic electroluminescent device composed of a pn junction of an inorganic semiconductor has been mainly used as an organic electroluminescent device. However, in the case of an inorganic electroluminescent device, a driving voltage is required to be AC 200V or more, and the size of the organic electroluminescent device is difficult because the device is manufactured in a vacuum state. In particular, there is a problem that it is difficult to obtain high efficiency blue color.

Due to these problems, research on organic electroluminescent devices using organic materials has been ongoing. The organic electroluminescence phenomenon is a phenomenon in which electrons and holes are transferred from the cathode and the anode, respectively, and are combined within the organic material when the electric field is applied to the organic material, and the energy generated is emitted as light.

The organic electroluminescent device manufactured using the organic electroluminescence phenomenon includes a single layer light emitting device having a structure in which a polymer organic material having light emitting characteristics is inserted between a transparent electrode and a metal electrode, and an organic light emitting layer between the electron transport layer and the hole transport layer. It can be divided into a multi-layered light emitting device that introduces, a brief description of a conventional organic electroluminescent device as follows.

1 is a cross-sectional view showing the structure of an organic electroluminescent device having a single layer consisting of a substrate / electrode / light emitting layer / electrode.

In the organic electroluminescent device, a substrate 101, an anode 103, an emissive layer 105, and a cathode 109 are sequentially formed from a lower layer thereof. The substrate 101 is made of glass or plastic. Typically, the anode 103 is coated with indium tin oxide (ITO), and the cathode 109 is coated with aluminum (Al).

The driving principle of the organic electroluminescent device of such a configuration is as follows. When a voltage is applied between the anode 103 and the cathode 109, holes injected from the anode 103 are moved from the anode 103 to the light emitting layer 105.

Meanwhile, electrons are injected into the light emitting layer 105 from the cathode 109. As such, carriers such as electrons and holes injected into the light emitting layer 105 recombine to form neutral excitons, and the excitons change from the excited state to the ground state, and thus the light emitting layer 105 The light is emitted to form a screen.

In FIG. 1, an organic electroluminescent device having a single layer type is illustrated, but a hole injection layer 105 coated with PEDOT or the like is disposed between the anode 103 and the light emitting layer 105, and the cathode 109 and the light emitting layer ( Between the 105 may be a multi-layer organic electroluminescent device having an electron injection layer or an entire embroidery transport layer not shown.

In particular, recently, a polymer is used as a material of the light emitting layer of the organic electroluminescent device, and the polymer corresponds to the energy difference because the energy level is separated into the conduction band and the home appliance by the superposition of the π-electron wave function of the main chain. The semiconductor properties of the polymer are determined by the band gap energy, and full color can be realized.

As such, the light emitting polymer using poly (paraphenylenevinylene) (PPV) in the organic electroluminescent polymer is a polymer in which one or two alkoxy groups, alkyl groups or aryl groups are substituted in the side chain of the main chain PPV. An electroluminescent device is manufactured.

For example, U.S. Patent No. 5,189,136 (Fred Wudl et al.) Discloses a poly [2-methoxy- substituted with a methoxy group and an alkoxy group in the side chain of a poly (paraphenylenevinylene) main chain. 5- (2'-ethylhexyloxy) -p-phenylenevinylene] (MEH-PPV) is disclosed. The compounds are described as being possible in the form of homopolymers, copolymers, blends or composites.

The poly (paraphenylenevinylene) derivatives mentioned above have excellent solubility in organic solvents, but their electrical properties are insufficient, and especially when used in single layer organic electroluminescent devices, they have poor adhesion to ITO or metal electrodes. Injection of electrons and electrons is not efficient, and when used in a multilayer thin film device, there is a problem in that the durability of the device is reduced because the interface adhesion with the charge transport layer is reduced.

In particular, in the process of preparing the precursor PPV derivative, which is a typical polymer-based organic electroluminescent device, due to the deterioration of solubility, a non-uniform polymer in which a precipitate is partially produced is produced simultaneously with the organic electroluminescent device using the same. There is a problem that the characteristics of the deterioration, there is a difficulty in controlling the polymerization conditions required to remove impurities generated during the polymerization process due to the decrease in solubility, there is a limit to mass production.

In addition, in the synthesis method of the conventional PPV derivative, a long time is consumed in the polymerization process for preparing the sulfonium precursor, which is a PPV precursor, and the yield is low, and high cost is required. In particular, in order to prepare a complete PPV derivative, it is necessary to remove the sulfonium salt, which is difficult to remove completely, and to form a light emitting layer in the form of a thin film (about 100 nm) in order to operate at a low voltage. As the nium salt is gradually removed, a pin hole is generated, thereby decreasing the uniformity of the film, and as a result, a leakage current is generated to lower the luminous efficiency.

In the Wittig reaction and Heck reaction, another method of preparing the PPV precursor, since the final synthesized polymer has a low molecular weight, the ability to form a thin film due to the polymer is inferior, and many metal catalysts are used in the polymerization reaction. In addition, there are problems that must go through many steps.

In order to solve this problem, U.S. Pat.Nos. 5,900,038 and 6,177,975 (Hwang et al.) Disclose that green light emission efficiency can be increased by using a soluble PPV derivative substituted with two silyl groups in the light emitting layer.

However, in the case of the organic electroluminescent device using the conventional PPV derivative including the PPV derivative disclosed in the US patent, the injection of holes is easier than the injection of electrons, the hole movement speed is significantly higher than the movement speed of electrons Therefore, there is a problem in that the luminous efficiency is lowered and the lifespan of the organic electroluminescent device is lowered due to the nonuniformity of the injected holes and electrons.

Therefore, while maintaining the solubility and electrical conductivity of the organic solvent intact, it is necessary to develop a new type of light emitting polymer without the above problems, and there is still a need in the industry to develop an organic electroluminescent device using the same.

The present invention has been proposed to solve the above problems, and the first object of the present invention is to deteriorate due to heat generated when driving the organic electroluminescent device by replacing a functional group having a large steric hindrance in the side chain of the produced light emitting polymer. The present invention is to provide a new type of light emitting polymer by the longitudinal polymerization method that can significantly improve the mechanical strength of the thin film.

Another object of the present invention is to provide a light emitting polymer that can greatly improve the luminous efficiency by reducing the difference between the injection of holes and electrons in the organic electroluminescent device.

It is still another object of the present invention to provide an organic electroluminescent device having high efficiency, wherein the organic electroluminescent polymer is manufactured using a light emitting layer, a hole transport layer electron injection layer, and an electron transport layer material.

According to one aspect, the present invention provides a polyfluorenylvinylene derivative composed of the following Chemical Formula 1 as a light emitting polymer having excellent heat resistance.

Formula 1

이고, R은 수소, 또는 탄소수 1~20의 직쇄 또는 측쇄의 지방족 알킬기, 탄소수 1~20의 알콕시기, 또는 방향족 치환기이며; n은 10 ~ 1000 사이의 정수임.)(Q in Formula 1 is

R is hydrogen or a linear or branched aliphatic alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an aromatic substituent; n is an integer between 10 and 1000.)

The polyfluorenyl vinylene derivative according to the present invention is characterized in that the weight average molecular weight is in the range of 5,000 to 10,000, preferably a fluorenyl group substituted with an aliphatic alkoxy group having 1 to 20 carbon atoms, more preferably It is preferable that it is substituted by the fluorenyl group substituted by the aliphatic alkoxy group of 5-15, or the linear or branched aliphatic alkyl group of 1-20 carbon atoms.

On the other hand, according to another aspect of the invention, there is provided an organic electroluminescent device doped with a polyfluorenyl vinylene derivative of the formula (1) as a light emitting layer.

The organic electroluminescent device manufactured according to the present invention may be a single layer organic electroluminescent device of a first electrode / light emitting layer / second electrode, a hole transport layer, an electron injection layer, between the first electrode and the second electrode, It may be an organic electroluminescent device of a multilayer thin film form further comprising at least one of the electron transport layer.

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

As described above, the organic electroluminescent device is configured to emit light by emitting energy absorbed by neutral excitons generated by the collision of holes and electrons emitted through the anode and the cathode in the light emitting layer, and the organic electroluminescent device In general, there is a problem in that the movement / emission rate of holes is much faster than the movement / emission rate of electrons and thus the luminous efficiency is lowered.

In the case of a conventional poly (florene) derivative, when the device is driven or heat is applied to the light emitting layer, the emission wavelength of the long wavelength is shown in the range of 500-600 nm due to the formation of excimer or aggregation of the light emitting polymer. As a result, color purity is lowered and luminous efficiency is lowered.

Therefore, in the present invention, a multi-layered organic material in which an electron injection layer and an electron transport layer are introduced to improve injection of electrons at the cathode to improve luminous efficiency, and a hole injection layer is introduced to facilitate injection of holes at the anode. A new Spiro-PFV, X₂-Spiro, in which side chains are substituted with other functional groups with large steric hinderance to improve the mechanical strength, which is a disadvantage of organic electroluminescent devices using PPV derivatives. -PFV and PFV derivatives were synthesized.

2 to 4 are each a spiro- fluorene having a skeleton and an aliphatic alkyl group, an alkyloxy group, or an aromatic substituent group of spirobifluorene, X₂-Spiro-PFV, and PFV introduced with an alkyl substituent according to a preferred embodiment of the present invention. It shows the process of synthesizing a monomer which is a precursor of a derivative.

First, according to the first embodiment of the present invention, 2,7-dibromoflorene is synthesized by reacting florene with bromine and using 2,7-dibromoflorene using an oxidizing agent. Synthesize -9-one ((2) of FIG. 2).

Subsequently, 2-bromobiphenyl ((3) in FIG. 2) is reacted with magnesium to prepare a Grignard reagent ((4) in FIG. 2), followed by compound 2,7-brobromoflorene-9- synthesized above. 2,7-dibromo-9- (2-biphenyl) -9-florenol ((5) of FIG. 2) by reacting with warm, and synthesized with 2,7-dibro via cyclization reaction with acetic acid Mo-9,9'-spirofluorene ((6) in FIG. 2) was synthesized and reacted with copper cyanide (I) to give 2,7-disaano-9,9'-spiroflorene ((7 in FIG. 2). )) And then 9,9'-spirofluorene-2,7-dicarboxylic acid ((8) of FIG. 2) through a hydrolysis reaction and 9,9'-pyrofloph through a reduction reaction Lauren-2,7-dimethanol ((9) of FIG. 2) was synthesized and finally reacted with thionyl chloride to yield 2,7-bis (chloromethyl) -9,9'- which is the monomer of Example 1. Spirobifluorene (FIG. 2 (10)) was synthesized.

The excellent solubility characteristics of light emitting polymers in general organic solvents can not only synthesize high molecular weight light emitting polymers, but also facilitate the fabrication of organic electroluminescent devices.

Synthesis of the light emitting polymer of Example 4 described later by Gilch polymerization method using the monomer of Example 1 has a very low solubility, and thus there is a limit to the application. Therefore, to compensate for the shortcomings of the monomer synthesized in Example 1, the monomer of Example 2 was synthesized as shown in FIG.

First, 2-bromo-5,3'-dimethoxybiphenyl ((11) in FIG. 3) is synthesized by reacting 3,3-dimethoxybiphenyl with NBS and reacted with a dimethyl sulfide compound to 2-bromo. Mobiphenyl-3,3-diol (Fig. 3 (12)) was prepared.

Then, 2-bromo-5,3'-bis (3,7-dimethyloctyloxy) ratio was reacted with 1-bromo-3,7-dimethyloctane to improve the solubility of the resulting monomer of Example 3. Phenyl ((13) in FIG. 3) was synthesized and reacted with 2,7-dibromofloren-9-one ((2) in FIG. 2) to give 9- (5,3'-bis (3,7-dimethyl Octyloxy) -biphenyl-2-yl) -2,7-dibromo-9H-fluorene-9ol (Fig. 3 (14)) was synthesized and cyclized with acetic acid to give 2,7- Dibromo-3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobifluorene (FIG. 3) is synthesized and then reacted with copper cyanide (I) To synthesize 2,7-dicyano-3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9, -spirobifluorene (FIG. 3) and undergo a hydrolysis reaction. Through 3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9, -spirobifluorene-2,7-dicarboxylic acid (Fig. 3 (17)) to synthesize and reduce 3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9, -spy The synthesized by Florencio-2,7-dimethanol (18 in Fig. 3).

Finally, the monomer of Example 2 reacts with thionyl chloride and the compound (Fig. 3 (18)) to give 2,7-bis (chloromethyl) -3 ', 6'-bis (3,7-dimethyloctyloxy). -9,9'-spirobifluorene (19 in Fig. 3) was synthesized.

When 1-bromooctyl is reacted to florene under a phase transfer catalyst, octyl groups are easily introduced into the 9th position of florene ((20) of FIG. 4), and paraforumaldehyde at 2nd and 7th positions of florene. When reacted with HCl in a 1,4-dioxane solvent, 2,7-bis (chloromethyl) -9,9'-dioctylfluorene (21 (Fig. 4)), a monomer having a chloromethyl group introduced thereto, was synthesized. .

On the other hand, Spiro-PFV, X₂-Spiro-PFV, and PFV derivatives prepared by the monopolymerization of the monomers prepared by the above method may increase the solubility or the solubility of the monomers other than the general alkyl substituents on the side chain thereof. Since the introduction of 3,7-dimethyloctyloxy substituents with florene, aliphatic alkyl or alkyloxy and aromatic substituents, problems caused by heat resistance, stability and aggregation of organic electroluminescent devices including PPV have been introduced. I can solve it.

The monomers finally synthesized in FIGS. 2, 3 and 4 can themselves form homopolymers via Gilch polymerization.

That is, 2,7-bis (chloromethyl) -9,9'-spirobifluorene as the finally synthesized monomer in FIG. 2 is potassium t-butoxide dissolved in THF in the presence of a THF solvent. In the presence of (t-BuOK) it can be reacted as in Scheme 1 below to synthesize poly (9.9'-spirobiflorenyl-2,7-vinylene) (Spiro-PFV).

Scheme 1

(n is an integer from 10 to 1000.)

Meanwhile, 2,7-bis (chloromethyl) -3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobifluorene, which is a monomer finally synthesized in FIG. 3, is a THF solvent. Poly (3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9 having a repeating unit as shown in Scheme 2 below by reacting with potassium t-butoxide dissolved in THF in the presence of '-Spirobiflorenyl-2,7-vinylene) (X 2 -Spiro-PFV) can be synthesized.

Scheme 2

(Alkyl, alkoxy and n are integers from 10 to 1000.)

Meanwhile, 2,7-bis (chloromethyl) -9,9-dioctylfluorene, a monomer finally synthesized in FIG. 4, is reacted with potassium t-butoxide dissolved in THF in the presence of a THF solvent. It is possible to synthesize poly (9,9-dioctylflorenyl-2,7-vinylene) (PFV) having a repeating unit as indicated in.

Scheme 3

(R: alkyl, alkyloxy or aromatic substituent, n is an integer from 10 to 1000.)

As described above, the synthesized Spiro-PFV, X₂-Spiro-PFV, and PFV homopolymers not only have excellent heat resistance to heat generated when the device is driven by the functional groups connected to the side chain, but also occur in the florescent light emitting material. Since it is possible to effectively suppress the peak occurring in the long wavelength of the green series can improve the color purity, it can be used as a light emitting layer coated between the electrodes of the organic electroluminescent device.

10 is a schematic cross-sectional view of an organic electroluminescent device to which Spiro-PFV, X₂-Spiro-PFV, and PFV, which are light emitting polymers manufactured according to the present invention, are applied.

As illustrated, the organic electroluminescent device includes a substrate 901, a first electrode 1002, a hole transport layer 1003, a light emitting layer 1004, an electron transport layer 1005, an electron injection layer 1006, and a second electrode ( It takes the form of a multilayer thin film composed of 1007).

The substrate 1001 may be made of glass or plastic, and is preferably made of glass.

Meanwhile, the first electrode 1002 and the second electrode 1007 function as an anode and a cathode, respectively, and the first electrode 1002 is connected to the second electrode 1007. In comparison, materials with a larger work function are used.

ITO (indium-tin oxide), polyaniline (polyaniline), polythiophene (polythiophene) and the like may be used as the first electrode 1002, and preferably ITO is used.

Meanwhile, gold, aluminum, copper, silver or alloys thereof, calcium / aluminum alloys, magnesium / silver alloys, aluminum / lithium alloys, and the like may be used as the second electrode 1007, and preferably aluminum or aluminum / It is a calcium alloy.

The electron injection layer 1006 is preferably LiF or BaF ₂ and the electron transport layer 1005 is Alq ₃ and BAlq ₃ .

On the other hand, as the light emitting layer 1004, Spiro-PFV, X₂-Spiro-PFV, and PFV derivative homopolymers synthesized according to the present invention are used by dissolving in a suitable organic solvent, preferably chlorobenzene.

In particular, when ITO is coated with the first electrode 1001, the uniformity of the surface of ITO and adhesion between Spiro-PFV, X₂-Spiro-PFV, and PFV derivative interfaces, which are light emitting polymers injected into the ITO and the light emitting layer 1004, are used. Since the driving voltage and the luminous efficiency of the organic electroluminescent device may be affected according to the capability, a hole transport layer 1003 coated with an organic material is preferably included between the first electrode 1002 and the light emitting layer 1004. Can be.

As the hole transport layer 1003, poly (3,4-ethylenedioxythiophene) -polystyrenesulfonate (PEPOT / PSS) may be used in a form coated on the first electrode.

In addition, in order to balance the electrons and holes in order to improve the luminous efficiency, an electron injection layer 1006 and an electron transport layer 1005 capable of effectively moving electrons to the light emitting layer 1004 are provided to the light emitting layer 1004 and the second electrode. It should be formed between (1007).

In FIG. 10, the electroluminescent device in the form of a multilayer thin film including a carrier injection layer or a carrier transfer layer between the light emitting layer 1004 and the electrodes 1001 and 1007 is described. However, the substrate 1001, the first electrode 1002, It is apparent to those skilled in the art that a single layer organic electroluminescent device composed of only the light emitting layer 1004 and the second electrode 1007 is possible.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following examples are only for illustrating the present invention, and the present invention is not limited by the following examples.

Example 1 Preparation of 2,7-bis (chloromethyl) -9,9'-spirobifluorene

(1) step 1: Preparation of 2,7-dibromoflorene

In a three-neck flask, florene (30 g, 180 mmol) was added thereto, and dichloromethane (300 ml) was added thereto, followed by stirring. The flask was blocked by light, cooled to 0 ° C. or lower, and when the temperature of the flask was sufficiently cooled, bromine (58 g, 364 mmol) was diluted in dichloromethane and dropped into the flask very slowly.

After stirring for 2 hours or more at 0 ℃ or less, and further stirred at room temperature for 24 hours. After the reaction, sodium carbonate solution was added little by little to adjust the pH to neutral. The excess bromine and bromic acid were removed in an aqueous sodium sulfate solution, the organic layer was extracted three times, dried over magnesium sulfate, and recrystallized with hexane and dichloromethane to give a white powder of 2,7-dibromoflorene. (50 g, yield: 80%) were obtained.

mp: 164-166 ° C.

¹ H-NMR (CDCl ₃ ): (ppm) 7.68 (d, J = 1.1 Hz, 2H), 7.64 (s, 1H), 7.59 (s, 1H), 7.54 (t, J = 0.91, 1H), 7.49 (t, J = 0.73 Hz, 1H), 3.87 (s, 2H).

¹³ C-NMR (CDCl ₃ ): (ppm) 144.65, 139.53, 130.00, 128.15, 121.05, 120.82, 36.47.

Anal. Calcd for C ₁₃ H ₈ Br ₂ : C, 48.19; H, 2.49; Br; 49.32. Found: C, 48.30; H, 2.58

(2) step 2: Preparation of 2,7-dibromofloren-9-one

In a three-neck flask, 2,7-dibromoflorene (20 g, 61 mmol) and acetic acid (300 ml) were added, K ₂ Cr ₂ O ₇ (18 g, 61.70 mmol) and cerium (III) carbonate hydrate (1.00 g, Small amount) was added at around 80 ° C.

The mixture of reaction was stirred at 120 ° C for 12 h. The reaction was then cooled to room temperature, diluted with distilled water and filtered. The obtained solid was washed in 10% aqueous sodium carbonate solution for 30 minutes, and washed several times in 80% sodium bisulfite solution for 30 minutes.

The resulting yellow solid was added to hydrochloric acid (100 ml), stirred at 80 ° C. for one hour, filtered, washed with distilled water and recrystallized with acetone to give a yellow solid of 2,7-dibromofluorene-9- Warm (19 g, yield: 91%) was obtained.

mp: 203-205 ° C

¹ H-NMR (CDCl ₃ ): (ppm) 7.76 (d, J = 1.8 Hz, 2H), 7.68 (d, J = 1.8 Hz, 1H), 7.62 (d, J = 1.8 Hz), 7.40 (s, 1H), 7.36 (s, 1 H).

¹³ C-NMR (CDCl ₃ ): (ppm) 142.327, 137.539, 135.406, 127.943, 123.484, 121.942.

IR (KBr): 3061 (C = O overtone), 1726 (C = O stretch), 1556-1416 (aromatic C = C stretch), 1245, 1184, 1056, 818, 782, 684, 465, 410 cm-1 .

Anal. Calcd for C ₁₃ H ₆ Br ₂ O: C, 46.20; H, 1.79; Br, 47.28; 0, 4.73. Found: C, 46.32; H, 1.83.

(3) step 3: preparation of 2,7-dibromo-9- (2-biphenyl) -9-florenol

Magnesium (1.4 g, 54 mmol) was added to a three-necked flask, and water was removed by decompression and nitrogen injection. Anhydrous ether (20 ml) was added thereto. A small amount of 1,2-dibroethane was added to activate magnesium, and a 2-bromobiphenyl (10.49 g, 45 mmol) solution diluted in anhydrous ether was slowly dropped into the flask and refluxed for 2-3 hours. Grignard reagents were prepared.

Another Erlenmeyer flask was prepared, and 2,7-dibromofloren-9-one (15 g, 44.40 mmol) and anhydrous ether were added under reflux, and the Grignard reagent prepared in advance was slowly dropped into the flask. After refluxing for 12 hours or more, the reaction was cooled to room temperature, and the yellow solid, which was precipitated, was filtered and washed with cold ether.

Then, put into 10% ammonium chloride solution, stirred for 10 hours, filtered, washed with distilled water, recrystallized from ethanol and 2,7-dibromo-9- (2-biphenyl) -9-florenol (13 g , Yield: 60%).

(4) step 4: preparation of 2,7-dibromo-9,9'-spirobifluorene

2,7-dibromo-9- (2-biphenyl) -9-florenol (11.89 g, 24.20 mmol) was added to acetic acid (200 ml) and stirred at 120 ° C. for 12 hours. Subsequently, hydrochloric acid (2-3 ml) was dropped into the reaction vessel and further stirred for 1-2 hours.

In the middle of the reaction, it was confirmed that the reactant falls to a white solid, and after the reaction was completed, a white solid precipitated. After that time the reaction was cooled sufficiently, the solid was filtered off and washed well with acetic acid and water. The resulting product was recrystallized in ethanol to obtain 2,7-dibromo-9,9'-spirobibirene (10.4 g, yield: 90%) as a white solid.

(5) step 5: Preparation of 2,7-dicyano-9,9'-spirobifluorene

2,7-Dibromo-9,9'-spirobibifluorene (10 g, 21 mmol) and copper cyanide (I) (4.54 g, 50.60 mmol) were added to dimethylformamide (200 ml) and 10 hours It was refluxed during. FeCl ₃ (hydrate, 25 g), concentrated hydrochloric acid (1 5 ml) and distilled water (150 ml) were prepared in a beaker, after the reaction was completed, the mixture of the reaction was poured into the beaker, and the temperature of the mixture in the beaker to remove the Cu complex It was kept for 30 minutes at 60-70 ℃.

The hot solution was extracted twice with ethyl acetate and the resulting organic layer was washed with dilute hydrochloric acid, water and 10% sodium hydroxide. After drying over magnesium sulfate, filtration and removing the solvent under reduced pressure, a dark brown product was obtained. The obtained product was recrystallized in methanol to give a yellow solid, 2,7-dicyano-9,9'-spirobibi. Florene (5.3 g, yield: 70%) was obtained.

(6) step 6: Preparation of 9,9'-spirobifluorene-2,7-dicarboxylic acid

2,7-dicyano-9,9'-spirobibifluorene (5,10 g, 3.92 mmol) was added to 30% sodium hydroxide (30 ml) and ethanol (35 ml) and refluxed for at least 6 hours. After the reaction was completed, the solvent was removed under reduced pressure, and the disodium salt of dicarboxylic acid precipitated as a yellow solid.

The yellow precipitate was filtered and placed in 25% aqueous hydrochloric acid solution and refluxed for 1-2 hours to obtain a light yellow solid. , 7-dicarboxylic acid (5.5 g, yield: 98%) was obtained.

(7) step 7: Preparation of 9.9'-spirobifluorene-2,7-dimethanol

In a round bottom flask under N ₂ atmosphere, 9,9'-spirobifluorene-2,7-dicarboxylic acid (5.60 g, 13.80 mmol) and purified benzene (120 ml) were added thereto, stirred, and dissolved in toluene. 65 wt% sodium bis (2-methyloxyethyloxy) aluminum hydride (RED-Al, 38.6 ml) was slowly added dropwise into the flask.

After refluxing for 2-3 hours, the reactant was poured into cold distilled water to remove excess reducing agent, acidified with concentrated hydrochloric acid, and extracted with chloroform to separate the organic layer.

The separated organic layer was washed with distilled water, dried over magnesium sulfate, the solvent was removed under reduced pressure, and recrystallized with benzene to give 9.9'-spirobifluorene-2,7-dimethanol (5 g, yield). : 96%).

(8) step 8: Preparation of 2,7-bis (chloromethyl) -9,9'-spirobifluorene

In a round bottom flask under N ₂ atmosphere, 9.9'-spirobifloren-2,7-dimethanol (6 g, 15.90 mmol) and purified benzene (150 ml) were added, and SOCl ₂ (39.8 g, 318 mmol) was added. It was slowly added dropwise into the flask at room temperature.

After dropping, the flask was refluxed at 120 ° C. for at least 12 hours. After the reaction was completed, the solvent benzene and excess SOCl ₂ was removed under reduced pressure, the reaction was poured into excess distilled water, extracted with chloroform to separate the organic layer.

The separated organic layer was washed several times with distilled water. After drying using anhydrous magnesium sulfate, it was filtered and the solvent was removed by pressure. The product was separated by column chromatography using a hexane / dichloromethane (9: 1) system. As a result, a white powder, 2,7-bis (chloromethyl) -9,9'-spirobibifluorene (5.2 g, Yield: 80%).

Example 2. Preparation of 2,7-bis (chloromethyl) -3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobifluorene

(1) step 9: Preparation of 2-bromo-5,3'-dimethoxybiphenyl

3.3-dimethoxybiphenyl (10 g, 46.70 mmol) was dissolved in 100 ml of dimethylformamide and cooled to 0 ° C. N-bromosuccinimide (NBS, 8.3 g, 46.7 mmol) diluted in dimethylformamide was slowly added dropwise at 0 ° C.

Stir at room temperature for about 12 hours, add distilled water, and then stir for about 10 minutes, extract with hexane, wash with distilled water several times, dry with anhydrous magnesium sulfate, and remove hexane under reduced pressure. Bromo-5,3'-dimethoxybiphenyl (13 g, yield: 95%) was obtained.

¹ H-NMR (CDCl ₃ ): (ppm) 7.55-7.51 (d, 1H), 7.34-7.30 (m, 1H), 7.00-6.91 (m, 4H), 6.88-6.74 (m, 1H), 3.90- 3.80 (d, 6 H).

Anal. Calcd for C ₁₄ H ₁₃ BrO ₂ : C, 57.36; H, 4. 47; Br, 27.26; O, 10.92. Found: C, 58.01; H, 4.82.

(2) step 10: preparation of 2-bromo-biphenyl-3,3'-diol

2-bromo-5,3'-dimethoxybiphenyl (12.40 g, 42.30 mmol), 150 ml dichloromethane and AlCl ₃ (56.40 g, 423 mmol) were added to a 500 ml three-necked flask, and cooled to 0 ° C. or lower. .

Methyl sulfide (31.5 g, 508 mmol) was slowly added dropwise into the flask at 0 ° C. for 30 minutes. As the reaction progressed, the starting material was completely disappeared through TLC, and the reaction was terminated.

After the reaction, the product was poured into the aqueous ammonium chloride solution very slowly, stirred for about 20 minutes, extracted with ether, and the organic layer was separated. The separated organic layer was then dried over magnesium sulfate, and the solvent was removed under reduced pressure to obtain 2-bromo-biphenyl-3,3'-diol (11 g, yield: 98%).

mp: 109-111 ° C.

¹ H-NMR (CDCl ₃ ): (ppm) 7.50-7.46 (d, 1H), 7.28 (m, 1H), 7.04-6.91 (m, 4H), 6.86-6.70 (m, 1H).

¹³ C-NMR (CDCl ₃ ): (ppm) 155.0, 154.9, 143.1, 142.3, 133.9, 129.2, 121.8, 118.1, 116.3, 116.2, 114.7, 112.8.

IR (KBr): 3443 (br, OH stretch), 1581-1459, 1314, 1219, 771 cm ^-1 .

Anal. Calcd for C ₁₂ H ₉ BrO ₂ : C, 54.37; H, 3. 42; Br, 30.14; O, 12.07. Found: C, 54.31: H, 3.52.

 (3) step 11: Preparation of 2-bromo-5,3'-bis (3,7-dimethyloctyloxy) -biphenyl

2-bromo-biphenyl-3,3'-diol (10.88 g, 41.04 mmol), potassium carbonate (34 g, 246.24 mmol), potassium iodide (6.81 g, 41.04 mmol) in dimethylformamide (150 ml) After melting, it was heated for 2 hours while maintaining the temperature of about 120 ℃.

The reaction mixture was then cooled to room temperature and 1-bromo-3,7-dimethyloctane (19.97 g, 90.29 mmol) was added dropwise. The reaction was refluxed for 18 hours while maintaining the temperature of about 150 ℃.

After the reaction, the mixture was extracted with distilled water and hexane, the separated organic layer was dried over anhydrous magnesium sulfate, and the solvent was removed under reduced pressure. Chromatographic purification on silica gel using 4% dichloromethane in hexanes gave 2-bromo-5,3'-bis (3,7-dimethyloctyloxy) -biphenyl (13 g, yield: 60%).

¹ H-NMR (CDCl ₃ ): (ppm) 7.53-7.49 (d, J = 8.8 Hz, 1H), 7.30 (t, J = 11.0 Hz), 6.98-6.79 (m, 4H), 6.77-6.74 (dd , J = 5.5 Hz, 1H), 3.99-3.96 (m, 4H), 1.63-1.53 (m, 10H), 1.32-1.13 (m, 11H), 0.95-0.84 (m, 17H).

Anal. Calcd for C ₃₂ H ₄₉ BrO ₂ : C, 70.44; H, 9.05; Br, 14.64; O, 5.86. Found: C, 70.56; H, 9.12.

(4) step 12: Preparation of 9- (5,3'-bis (3,7-dimethyloctyloxy) -biphenyl-2-yl) -2,7-dibromo-9H-floren-9ol

₂ -bromo-5,3'-bis (3,7-dimethyloctyloxy) -biphenyl (10.80 g, 19.79 mmol) and dried tetrahydrofuran (150 ml) were placed in a three-necked flask under N ₂ atmosphere. After cooling to 78 ° C. tert-butyllithium (1.7M, 27.94 ml, 47.50 mmol) was added very slowly.

The resulting product was stirred for 1 hour while maintaining the temperature of -78 ℃, and further stirred for 1 hour while gradually raising the temperature to room temperature after 1 hour. Then the temperature of the reaction was again lowered to -78 ° C and 2,7-dibromofluorene-9-one (8.03 g, 23.8 mmol) dissolved in dried tetrahydrofuran (70 ml) was added very slowly dropwise.

After stirring for 1 hour, the temperature was gradually raised to room temperature and stirred for about 6 hours. After the reaction was terminated by adding distilled water, the mixture was extracted using chloroform or dichloromethane, and the separated organic layer was dried over magnesium sulfate, and the solvent was removed under reduced pressure.

Chromatographic purification on silica gel using 30-40% dichloromethane in hexane yielded a yellow solid. The obtained product was recrystallized several times using methanol to obtain 9- (5,3'-bis (3,7-dimethyloctyloxy) -biphenyl-2-yl) -2,7-dibromo as a white powder. -9H-Floren-9ol (9.5 g, yield: 60%) was obtained.

mp: 104-105 ° C.

¹ H-NMR (CDCl ₃ ): (ppm) 8.28 (d, J = 8.8 Hz, 1H), 7.35-7.29 (m, 4H), 7.07-7.02 (m, 3H), 6.57 (t, J = 7.9 Hz , 1H), 6.53 (d, J = 2.8Hz, 1H), 6.41 (dd, J = 2.6Hz, 1.0Hz, 1H), 5.68-5.65 (m, 2H), 3.99 (t, J = 6.6Hz, 2H ), 3.55 (t, J = 6.6 Hz, 2H), 1.82 (m, 1H), 1.76-1.46 (m, 6H), 1.38-1.24 (m, 6H), 1.22-1.1 (m, 6H), 0.94 ( d, J = 5.9 Hz, 7H), 0.90-0.87 (dd, J = 8.6Hz, 9.7Hz, 12H).

¹³ C-NMR (CDCl ₃ ): (ppm) 158.43, 157.63, 152.75, 152.70, 142.11, 141.40, 138.25, 138.23, 132.05, 130.07, 128.06, 127.94, 127.79, 127.60, 122.15, 122.04, 121.64, 121.51, 121.51, 121.51, 121.51 113.78, 113.69, 113.46, 113.31, 82.13, 66.55, 66.04, 65.93, 39.51, 39.45, 37.65, 37.56, 37.49, 36.48, 30.17, 30.07, 28.23, 28.20, 24.94, 24.87, 22.96, 22.93, 22.85, 22.83, 20.83 19.90.

IR (KBr): 3530 (OH stretch), 3054, 2928 (sp ₃ CH stretch), 2358, 1596 (CH ₂ bend), 1570 (CH ₃ bend), 1469-1383, 1301, 1247 (CO stretch), 1225 , 1186, 1132, 1027, 836, 788, 702, 677, 454 cm ^-1 .

Anal. Calcd for C ₄₅ H ₅₆ Br ₂ O ₃ : C, 67.16; H, 7.01; Br, 19.86; O, 5.96. Found: C, 67.21; H, 7.916.

(5) step 13: Preparation of 2,7-dibromo-3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobibifluorene

9- (5,3'-bis (3,7-dimethyloctyloxy) -biphenyl-2-yl) -2,7-dibromo-9H-floren-9ol (5.30 g) in a 250 ml three-neck flask , 6.59 mmol), acetic acid (150 ml) and hydrochloric acid (3 ml) were added and stirred at room temperature for 24 hours. After the reaction, acetic acid was removed under reduced pressure, and the obtained product was extracted with chloroform or dichloromethane.

The obtained organic layer was dried over magnesium sulfate, the solvent was removed under reduced pressure, purified by chromatography on silica gel using 4% dichloromethane in hexane, and the obtained product was recrystallized from hexane to give 2,7-dibromo-3. ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobibifluorene (4.8 g, yield: 93%) was obtained.

mp: 82-85 ° C.

¹ H-NMR (CDCl ₃ ): (ppm) 7.67-7.63 (d, J = 8.4 Hz, 2H), 7.49 (d, J = 1.5 Hz, 2H), 7.32 (d, J = 2.2 Hz, 2H), 6.86 (d, J = 1.8Hz, 2H), 6.72-6.68 (dd, J = 8.1Hz, J = 2.2Hz, 2H) 6.60 (d, J = 8.4Hz), 4.10 (t, J = 6.5Hz, 4H ), 1.91-1.82 (m, 2H), 1.68-1.53 (m, 5H), 1.36-1.19 (m, 12H), 1.00-0.87 (m, 19H).

¹³ C-NMR (CDCl ₃ ): (ppm) 159.75, 151.15, 147.95, 144.16, 142.96, 139.56, 139.39, 133.97, 132.46, 130.90, 127.27, 124.60, 121.82, 121.27, 114.68, 105.93, 101.12, 68.61, 68.61 64.43, 39.25, 37.03, 36.32, 32.33, 29.86, 27.99, 24.68, 22.72, 22.62, 20.53, 19.69.

IR (KBr): 2926 (sp ₃ CH stretch), 1882, 1607, 1583, 1469, 1396, 1307, 1276, 1237, 1089, 1015, 1006, 944, 827, 731, 656 cm ^-1 .

Anal. Calcd for C ₄₅ H ₅₄ Br ₂ O ₂ : C, 68.70; H, 6.92; Br, 20.31; O, 4.07. Found: C, 69.96; H, 7.911.

(6) step 14: Preparation of 2,7-dicyano-3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobifluorene

2,7-dibromo-3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobifluorene (8.20 g, 10.40 mmol) and copper cyanide (I) (2.24 g , 25 mmol) was added to dimethylformamide (200 ml) and refluxed for 10 hours.

FeCl ₃ (hydrate, 25 g), concentrated hydrochloric acid (10 ml), distilled water (100 ml) were prepared in a beaker, after the reaction was completed, the mixture of the reaction was poured into the beaker, and the temperature of the mixture in the beaker to remove the Cu complex It was kept for 30 minutes at 60-70 ℃. The hot solution was extracted twice with ethyl acetate and the resulting organic layer was washed with dilute hydrochloric acid, water and 10% sodium hydroxide.

After drying over magnesium sulfate, filtration and removing the solvent under reduced pressure, a dark brown product was obtained. The obtained product was recrystallized in methanol to give 2,7-dicyano-3 ', 6'-bis as a yellow solid. (3,7-dimethyloctyloxy) -9,9'-spirobifluorene (5 g, yield: 70%) was obtained.

mp: 116-117 ° C.

¹ H-NMR (CDCl ₃ ): (ppm) 7.97-7.93 (d, J = 8.1 Hz, 2H), 7.72-7.68 (d, 8.1 Hz, 2H), 7.36 (s, 2H), 7.08 (s, 2H ), 6.73-6.69 (d, J = 8.8 Hz, 2H), 6.56-6.52 (d, J = 8.8 Hz), 4.10 (t, J = 6.6 Hz, 4H), 1.98-1.48 (m, 7H), 1.46 -1.09 (m, 12H), 0.99 (d, J = 5.8 Hz, 7H), 0.90 (dd, J = 8.6 Hz, 9.7 Hz, 12H).

¹³ C-NMR (CDCl ₃ ): (ppm) 160.29, 151.205, 143.833, 143.328, 137.847, 132.296, 128.226, 124.45, 121.745, 118.686, 115.248, 112.872, 106.618, 67.052, 64.848, 39.645, 37.694, 36.668, 30.302, 28.396, 25.095, 23.139, 23.037, 20.130.

IR (KBr): 3060, 2926 (sp ₃ CH stretch), 2225 (CN stretch), 1606 (CH ₂ bend), 1581 (CH ₃ bend), 1494, 1462, 1413, 1306, 1244-1174, 1020, 883 , 831, 769, 722, 642 cm ^-1 .

Anal. Calcd for C ₄₇ H ₅₄ N ₂ O ₂ : C, 83.14; H, 8.02; N, 4.13; 0, 4.71. Found: C, 84.38; H, 9.326, N; 4.208.

(7) step 15: Preparation of 3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobifluorene-2,7-dicarboxylic acid

2,7-dicyano-3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobifluorene (5 g, 7.40 mmol) was mixed with 30% sodium hydroxide (30 ml). It was added to ethanol (30 ml) and refluxed for 6 hours or more. After the reaction was completed, the solvent was removed under reduced pressure, and the disodium salt of dicarboxylic acid precipitated as a yellow solid.

The yellow precipitate was filtered and then placed in 25% aqueous hydrochloric acid solution and refluxed for 1-2 hours to obtain a light yellow solid, which was recrystallized using acetic acid again to obtain yellow crystals 3 ', 6'-bis (3, 7-dimethyloctyloxy) -9,9'-spirobifluorene-2,7-dicarboxylic acid (5.1 g, yield: 97%) was obtained.

mp: 280-284 ° C, decomposition at 285 ° C.

¹ H-NMR (DMSO-d ₆ ): (ppm) 8.30 (d, J = 8.1 Hz, 2H), 8.12 (d, J = 8.1 Hz), 7.80 (s, 2H), 7.24 (s, 2H), 6.82-6.78 (d, J = 8.8 Hz, 2H), 6.60 (d, J = 8.8 Hz, 2H), 4.20 (s, 4H), 1.98-1.50 (m, 7H), 1.46-1.05 (m, 12H) , 1.01 (d, J = 5.7 Hz, 7H), 0.95 (dd, J = 8.6 Hz, 9.7 Hz, 12H).

¹³ C-NMR (DMSO-d ₆ ): (ppm) 167.302, 159.875, 150.537, 144.733, 143.434, 139.581, 131.674, 103.077, 124.839, 124.601, 122.068, 115.592, 107.129, 66.855, 64.767, 37.462, 36.617, 30.166, 28.23, 24.969, 23.361, 23.260, 20.328.

IR (KBr): 3175-2553 (OH stretch), 2927 (sp ₃ CH stretch), 1687 (C = O stretch), 1607, 1494-1365 (aromatic C = C stretch), 1293, 1245, 1178 (CO stetch ), 1024, 838, 755, 664, 503 cm ^-1 .

Anal. Calcd for C ₄₇ H ₅₆ O ₆ : C, 78.74; H, 7.87; O, 13.39. Found: C, 77.36; H, 8.063

(8) step 16: Preparation of 3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobifluorene-2,7-dimethanol

3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobifluorene-2,7-dicarboxylic acid (4.50 g, 6.30 mmol) in a round bottom flask under N2 atmosphere And purified benzene (130 ml) was added thereto, followed by stirring. Then, 65 wt% of sodium bis (2-methyloxyethyloxy) -aluminum hydride (RED-Al, 30 ml) dissolved in toluene was slowly added dropwise into the flask.

After refluxing for 2-3 hours, the reactant was poured into cold distilled water to remove excess reducing agent, acidified with concentrated hydrochloric acid, and extracted with chloroform to separate the organic layer.

The separated organic layer was washed with distilled water, dried over magnesium sulfate, the solvent was removed under reduced pressure, and recrystallized with benzene and methanol to obtain 3 ', 6'-bis (3,7-dimethyloctyloxy)-. 9,9'-Spyrobifluorene-2,7-dimethanol (4 g, yield: 93%) was obtained.

mp: 47-50 ° C.

¹ H-NMR (CDCl ₃ ): (ppm) 7.83-7.75 (t, J = 7.3 Hz, J = 8.8 Hz, 2H), 7.40-7.23 (m, 4H), 6.74-6.52 (m, 6H), 4.54 (d, J = 9.5 Hz, 4H, -CH2OH), 4.08 (t, J = 7.3 Hz, 4H, -OCH2-), 1.95-1.47 (m, 7H), 1.44-1.07 (m, 12H), 0.98 ( d, J = 6.6 Hz, 7H), 0.88 (dd, J = 8.6Hz, 9.7Hz, 12H).

¹³ C-NMR (CDCl ₃ ): (ppm) 159.536, 150.022, 143.136, 141.209, 140.911, 140.739, 126.73, 124.753, 122.706, 120.132, 114.733, 105.911, 66.926, 65.596, 64.939, 39.645, 37.709, 36.758, 30.308, 28.381, 25.08, 23.118, 23.017, 20.115.

IR (KBr): 3389 (OH stretch), 2926 (sp 3 CH stretch), 2868, 1607, 1581, 1467, 1383, 1303, 1219 (CO stretch), 1172, 1024, 818, 771, 668, 641 cm - ¹ .

Anal. Calcd for C ₄₇ H ₆₀ O ₄ : C, 81.93; H, 8.78; O, 9.29. Found: C, 82.64; H, 8.163

(9) step 17: Preparation of 2,7-bis (chloromethyl) -3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobifluorene

3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobifluorene-2,7-dimethanol (3.50 g, 5.08 mmol) in a round bottom flask under N ₂ atmosphere Purified benzene (50 ml) was added and SOCl 2 (12.10 g, 101.60 mmol) was slowly added dropwise into the flask at room temperature.

After dropping, the flask was refluxed at 120 ° C. for at least 12 hours. After the reaction was completed, the solvent benzene and excess SOCl 2 was removed under reduced pressure, the reaction was poured into excess distilled water, extracted with chloroform to separate the organic layer.

The separated organic layer was washed several times with distilled water. After drying with anhydrous magnesium sulfate, the mixture was filtered and the solvent was removed under reduced pressure. The product was separated by column chromatography using a hexane / dichloromethane (9: 1) system. As a result, a white powder, 2,7-bis (chloromethyl) -3 ', 6'-bis (3,7-dimethyl Octyloxy) -9,9'-spirobibirene (2.9 g, yield: 80%) was obtained.

mp: 89-89 ° C

¹ H-NMR (CDCl ₃ ): (ppm) 7.83-7.79 (d, J = 7.3 Hz, 2H), 7.44-7.40 (dd, J = 8.1 Hz, 1.5Hz, 2H), 7.35 (d, J = 2.2 Hz, 2H), 6.74-6.58 (m, 6H), 4.45 (s, 4H, -CH2Cl), 4.09 (t, J = 7.3 Hz, 4H, -OCH2-), 1.98-1.47 (m, 7H), 1.44 -1.09 (m, 12H), 0.99 (d, J = 5.9 Hz, 7H), 0.89 (d, J = 6.6 Hz, 12H).

¹³ C-NMR (CDCl ₃ ): (ppm) 159.52, 150.14, 142.98, 141.11, 140.43, 137.25, 128.61, 128.53, 128.38, 124.74, 124.65, 124.14, 120.43, 120.31, 114.57, 105.74, 66.54, 64.52, 46.30, 46.30 46.24, 39.24, 39.20, 37.31, 36.33, 29.86, 27.98, 24.67, 22.71, 22.60, 22.55, 19.70.

IR (KBr): 2926 (sp 3 CH stretch), 2868, 1617, 1581, 1493, 1467, 1306, 1267, 1242, 1225, 1175, 1021, 834, 733, 698, 638, 571, 427, 358 cm - ¹ .

Anal. Calcd for C ₄₇ H ₅₈ Cl ₂ O ₂ : C, 77.77; H, 8.05; Cl, 9.77; O, 4.41. Found: C, 76.90; H, 7.633.

Example 3. Preparation of 2,7-bis (chloromethyl) -9,9-dioctylfluorene

(1) step 18: preparation of 9,9-dioctylfluorene

In a 250 ml three-necked flask, dimethyl sulfoxide (100 ml) was added as a solvent, followed by aqueous solution of florene (3 g, 18.04 mmol), sodium hydroxide (4.3 g, 1.1 mol, 50% w / w) and a small amount of tetrabutylammonium as a phase transfer catalyst. Add bromide (TABA) and stir.

1-bromooctane (8.7 g, 45.1 mmol) was slowly added thereto, followed by reaction at room temperature for 24 hours. After the reaction is completed, the mixture is extracted with water and ethyl acetate, an organic layer is added, anhydrous magnesium sulfate is added, the filtrate is dried and the solvent is removed.

The reaction mixture thus obtained was identified by TLC (eluent: hexane), and 9,9-dioctylfluorene was purified by column chromatography using hexane as a developing solvent. The yield was 70% and the structure was confirmed by 1 H-NMR.

¹ H-NMR (CDCl ₃ ): (ppm) 7.62 (t, 2H), 7.40-7.18 (m, 6H), 1.90 (m, 4H), 1.26-1.05 (m, 16H), 0.83 (t, 6H) , 0.58 (m, 4 H).

(2) step 19: Preparation of 2,7-bis (chloromethyl) -9,9-dioctylfluorene

In a 250 ml three-necked flask, 1,4-dioxane is added as a solvent, and 9,9-dioctylfluorene (4 g, 10.24 mmol), excess HCl and forumaldehyde are added thereto. The reaction mixture is reacted at 90 ° C. for about 72 hours.

After completion of the reaction, the mixture was extracted with water and ethylacetate, and the solvent was removed to purify 2,7-bis (chloromethyl) -9,9-dioctylfluorene by column chromatography. The yield was 70% and the structure was confirmed by ¹ H-NMR.

¹ H-NMR (CDCl ₃ ): (ppm) 7.69 (d, 2H), 7.38 (d, 4H), 4.7 (s, 4H), 1.90 (m, 4H), 1.26-1.0 5 (m, 16H), 0.8 3 (t, 6H), 0.58 (m, 4H).

Example 4 Preparation of Poly (9,9'-Spirobiflorenyl-2,7-vinylene) (Spiro-PFV)

2,7-bis (chloromethyl) -9,9'-spirobifluorene (4.5 ml of potassium t-butoxide (1.0 M THF solution, 6 mmol) dissolved in anhydrous toluene (20 ml) under nitrogen atmosphere) 0.30 g, 1 mmol) was slowly added dropwise at room temperature for about 10 minutes using a syringe pump.

After the dropwise addition, the mixture was stirred at room temperature for 24 hours. After 24 hours, a very small amount of 4-t-butylbenzyl bromide was added, followed by further stirring for 2 hours to replace the polymer terminal with 4-t-butylbenzyl group.

The polymer solution was dropped into 600 ml of methanol to precipitate the polymer, and then the polymer was filtered through a thimble to remove the monomer, impurities, oligomers, etc. that remained without reaction by Soxhlet using methanol, isopropyl alcohol, and hexane.

After that, the polymer solution dissolved in toluene was put into the membrane filter, and left in the toluene solution for about one week to remove low molecular weight polymers. Thereafter, the resultant was precipitated in 500 ml of methanol, and the resultant was filtered and dried to obtain poly (9.9'-spirobifluorenyl-2,7-vinylene) as a light yellow polymer in a yield of 40%.

Example 5. Preparation of Poly (3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobiflorenyl-2,7-vinylene) (X₂-Spiro-PFV)

2,7-bis (chloromethyl) -3 ', 6'-bis (3,7) in 2.5 ml of potassium t-butoxide (1.0 M THF solution, 6 mmol) in anhydrous THF (20 ml) under nitrogen atmosphere To a solution of -dimethyloctyloxy) -9,9'-spirobifluorene (0.30 g, 1 mmol) was slowly added dropwise at room temperature for 30 minutes or more using a syringe pump.

After the dropwise addition, the mixture was stirred at room temperature for 24 hours, and after 24 hours, a very small amount of 4-t-butylbenzyl bromide was added and stirred for about 2 hours to replace the polymer terminal with 4-t-butylbenzyl group.

The polymer solution was dropped in 600 ml of methanol to precipitate the polymer, and the polymer was filtered through a thimble to remove monomers, impurities, oligomers, etc. that remained without reacting with Soxhlet using methanol, isopropyl alcohol, and hexane.

Then, the polymer solution dissolved in chloroform was added to the membrane filter, and left for one week under the chloroform solution to remove low molecular weight polymers. It was then precipitated again in 500 ml methanol, filtered and dried to give poly (3 ', 6'-bis (3,7-dimethyloctyloxy) -9,9'-spirobifluorenyl-2, a light yellow polymer. , 7-vinylene) was obtained in a yield of 70%.

¹ H-NMR (CDCl ₃ ): (ppm) 7.64-6.56 (br, 12H, aromatic protons), 6.53-6.33 (br, 2H, vinylic protons), 4.00 (br, 4H), 2.56 (TBB), 1.85- 0.80 (br, 38H).

Anal. Calcd for (C ₄₉ H ₆₂ O ₂ ) n: C, 86.17; H, 9. 15; 0, 4.68. Found: C, 87.64; H, 11.20.

Example 6. Preparation of Poly (9,9-Dioctylfluorenyl-2,7-vinylene) (PFV)

 Prepare 2,7-bis (chloromethyl) -9,9-dioctylfluorene (0.377 g, 0.873 mmol) in a 100 ml polymerization flask and remove the water completely with Schlenk line. Then purified THF (50 ml) is added and stirred for about 30 minutes in an ice-bath.

When the temperature is low enough, drop 5.24 ml (1.0 M THF solution, 5.24 mmol) of potassium t-butoxide for 30 minutes. After the excess potassium t-butoxide was injected, the mixture was stirred for 18 hours at room temperature, and then the polymer reactant was slowly dropped into the dropper while stirring in 500 ml of methanol to precipitate.

The precipitated polymer was filtered out, and impurities and oligomers were removed in 250 ml methanol by Soxhlet for 12 hours to purify the luminescent polymer first, and then the polymer was dissolved in 250 ml chloroforum.

After reprecipitation in methanol again, it was dissolved in a minimum amount of chloroforum, injected into a membrane filter, and then subjected to a polymer cutting process for 4 days to remove the molecular weight of less than 80,000, and then precipitated in the same manner as the first precipitation in 500 ml methanol. Filter to obtain pure poly (9,9-dioctylflorenyl-2,7-vinylene) polymer.

Table 1. Physical Properties of Synthesized Spiro-PFV, X₂-Spiro-PFV, and PFV

polymer Mw ^a (× 10 ^-4 ) PDI ^a yield(%) DSC (Tg) (° C) TGA ^b (℃) Spiro-PFV - - 40 171 407 X₂-Spiro-PFV 4.3 2.8 70 170 420 PFV 22.2 2.1 82 173 415

^a : Molecular weight (Mw) and polydispersity (PDI) of the polymer were determined by GPC using polystyrene standards

^b : thermogravimetric analysis (TGA) is a temperature at which the weight of the polymer is reduced by 5%.

Example 7: Molecular weight cleavage and high purity purification of luminescent polymer using Membrane filter

Spiro-PFV, X₂-Spiro-PFV and PFV, each of the light emitting polymers synthesized in Examples 4 to 6, were dissolved in a small amount of chloroforum, and then placed in a membrane tube (Spectrum, USA) made of polyvinylidene fluoride (PVDF). .

The membrane tube was placed in a 1 L beaker with 800 mL of chloroform and low molecular weight polymer was removed by osmosis for about a week while stirring with a magnetic bar. The luminescent polymer in the membrane tube was again precipitated in methanol, filtered and dried to obtain highly purified luminescent polymer.

Example 8: FT-IR measurement of light emitting polymer film

The FT-IR of the X₂-Spiro-PFV synthesized in Example 5 was measured. The measurement was performed according to a conventional method and the results are shown in FIG.

Example 9: UV-visible absorption spectrum measurement of luminescent polymer film

Spiro-PFV, X₂-Spiro-PFV, and PFV solutions, which are synthesized in Examples 4 to 6, respectively, and purified through Example 7, were spin-coated on a glass substrate to form a polymer thin film, and then UV-visible. Absorbance was measured.

Each synthesized polymer was dissolved in chlorobenzene at a concentration of 0.5 wt%, spin coated to a thickness of about 80 nm on a quartz substrate, and UV-visible absorption spectra were measured using a Shimadzu UV-3100 spectrometer.

The UV absorption peaks for each synthesized luminescent polymer are shown in Table 2, and the UV absorption peaks of Spiro-PFV, X 2 -Spiro-PFV, and PFV are shown in FIG. For comparison, each result was normalized.

As shown, the maximum UV absorption peaks of Spiro-PFV, X₂-Spiro-PFV, and PFV synthesized in the above examples occurred at about 372 nm and 409 to 419 nm. In particular, in the case of PFV introduced with less steric hindrance, the absorption occurs at longer wavelengths than Spiro-PFV and X₂-Spiro-PFV. It can be seen that the effective conjugate length increased relatively.

Example 10 Measurement of photoluminescence (PL) and electroluminescence (EL) of luminescent polymer films

In the present Example, PL and EL were measured for Spiro-PFV, X₂-Spiro-PFV, and PFV, which were synthesized in Examples 4 to 6 and purified in Example 7, respectively. First, the synthesized luminescent polymer was dissolved in chlorobenzene at a concentration of 0.5 wt%, spin-coated to a thickness of about 80 nm on the upper surface of the quartz substrate, and then Hitachi F-4500 and Minolta CS-1000. Measured by.

Subsequently, a solid state emission measurement was performed on a thin film formed on a quartz substrate having an angle of 45 degrees with respect to the excitation beam direction using the UV maximum absorption wavelength measured in each light emitting polymer as the excitation wavelength. PL and EL values for each polymer are shown in Table 2.

8 shows PL spectra of Spiro-PFV, X₂-Spiro-PFV, and PFV, respectively, and were normalized for comparison.

As shown, the maximum emission peak is formed at approximately 466 nm and the shoulder peak is generated near 500 and 530 nm. In particular, unlike the UV-visible absorption spectrum, even if a substituent having different steric hindrance is introduced at the position 9 of floren, it can be seen that there is no significant change in the position of the emission peak.

9 shows EL values measured for Spiro-PFV, X₂-Spiro-PFV, and PFV synthesized according to the present embodiment, respectively, and the measured values are normalized for comparison. As shown in the figure, it can be seen that the EL spectrum is almost identical to the PL spectrum.

Example 11 Fabrication of Organic Electroluminescent Device

An organic electroluminescent device was manufactured using piro-PFV, X₂-Spiro-PFV, and PFV derivatives having an average molecular weight of 5,000 to 1,000,000 in the light emitting polymers prepared in Examples 4, 5, and 6.

10 is a cross-sectional view of an organic electroluminescent device manufactured according to this embodiment.

The organic electroluminescent device cleans a transparent electrode substrate coated with indium tin oxide (ITO) on a glass substrate, and then finely cleans the transparent electrode substrate coated with ITO using photoresist resin and etchant. The anode was formed using a processing process and then washed again.

The hole injection layer was coated with a polythiophene derivative, poly (3,4-ethylenedioxythiophene) -poly (styrenesulfonate) (PEDOT), 100 μm thick, and baked at 110 ° C. for about 50 minutes.

Spiro-PFV, X₂-Spiro-PFV, and PFV solutions, each of which were prepared by dissolving in chlorobenzene, were spin-coated on the hole injection layer, and after the baking process, the solvent was completely removed in a vacuum oven to remove the light emitting layer of the polymer thin film. Formed. The polymer solution was spin-coated by filtering with a 0.2 ㎛ filter, the thickness of the light emitting polymer was about 80 ~ 200 nm.

In addition, Alq ₃ can easily transfer electrons, and a thin film is sequentially formed by vacuum deposition of LiF, an electron transport layer and an electron injection layer, and then an Al electrode, a cathode, is formed, and Alq ₃ , an electron transport layer, is not introduced. A multi-layered organic electroluminescent device was fabricated in which LiF, an electron injection layer, and Al electrode, a cathode, were introduced.

The vacuum degree for vacuum deposition was deposited while maintaining the 4 × 10 ^-6 torr or less to form a thin film. During deposition, the film thickness and growth rate were controlled by using a crystal sensor. The emission area was 4 ㎜ and the driving voltage was a direct bias voltage.

Table 2. Measurement of optical and electrical properties of synthesized light emitting polymers

 Light emitting polymer Absorbance (nm)  Max PL (nm)   Max PL (nm) Eg (eV) ^a HOMO (eV) ^b    LUMO (eV)   Spiro-PFV     372   466, 500, 533 469, 499 ^c , 535 ^c     2.62      -      - X ₂ -Spiro- PFV 409,377 ^c   467, 500, 533 467, 500 ^c , 533 ^c     2.65     5.25     2.60      PFV      419   466, 500, 533 469 ^c , 499, 535 ^c     2.6     5.3     2.7

^a : crystal at the edge of the absorption spectrum

^b : determined from onset of anodic scan of cyclic voltammetry

^c : shoulder

Example 12 Measurement of Electro-optical Properties of Electroluminescent Devices

In Example 11, electro-optical properties were measured from organic electroluminescent devices coated with respective light emitting polymers.

The current density and luminance of the organic electroluminescent device fabricated according to Example 11 were measured using Keithley 236 Source Measurement and Minolta LS-100, and the organic electroluminescence with each polymer coated on the light emitting layer. The starting drive voltage, maximum light emission, maximum light emission efficiency and CIE of the device are shown in Table 3.

11 is a graph showing the current density and the intensity of the light emitting luminance according to the applied voltage of the X₂-Spiro-PFV coated organic electroluminescent device, Figure 12 is a graph of the organic electroluminescent device coated with X₂-Spiro-PFV It is a graph showing the luminous efficiency according to the applied current density.

As shown, the organic light emitting diode coated with the light emitting polymer synthesized according to the present invention starts to operate at a voltage of approximately 7V, and as the voltage increases, the amount of carrier injected is increased, and as a result, the current density (current It can be seen that density increases exponentially.

In particular, FIGS. 13A and 13B illustrate changes in EL spectra of X₂-Spiro-PFV and PFV according to the applied voltage, and X₂-Spiro-PFV is difficult to observe the change in the EL spectrum with respect to the applied voltage. And it can be seen that it is very stable against the heat generated when driving the device.

Table 3. Electro-optical Properties of Polymer-coated Organic Electroluminescent Devices

   Light emitting polymer    Drive voltage (V) Brightness (cd / m ² )    Luminous Efficiency (cd / A) CIE (x, y) ^a    Spiro-PFV        -        -        -        - X ₂ -Spiro- PFV        7.0       4065        1.2   (0.25, 0.40)       PFV       2.5       760       0.16

^a : calculated from the EL spectrum.

Comparative Example: Measurement of Physical Properties of Organic Electroluminescent Device Made of MEH-PPV

Instead of Spiro-PFV, X₂-Spiro-PFV, and PFV derivatives synthesized in the present invention, the optical properties of the previously disclosed (US Pat. No. 5,189,136) MEH-PPV and an organic electroluminescent device coated with the MEH-PPV on the light emitting layer The electro-optical properties of were measured.

14A is a result of measuring the UV absorption, PL spectrum, and EL spectrum of MEH-PPV with the voltage fixed at 10V. As shown in FIG. 14A, the MEH-PPV emits light in the red region (about 600 nm wavelength). Can be.

FIG. 14B is a graph showing current density according to an applied voltage of an electroluminescent device using MEH-PPV as a light emitting layer, and it can be seen that current gradually flows at a driving voltage of about 3V.

In the above description of the preferred embodiment of the present invention, but this is only an example, and various modifications and changes to the present invention are possible, and such modifications and changes as long as it does not impair the spirit of the present invention It will be apparent from the appended claims that they belong to the scope of the invention.

 The light emitting polymer synthesized in the present invention has a higher molecular weight than the conventional PPV-based polymer and can be easily dissolved in an organic solvent to form a large area light emitting area. X₂-Spiro-PFV and PFV derivatives were synthesized for the first time by Gilch polymerization method. In order to suppress the long-wavelength light emission during device driving in poly (Florene) system, spirobifluorenylvinylene-type light emitting polymer structure was developed. By introducing an aromatic alkyl or alkyloxy substituent or an aromatic substituent so as to have excellent adhesion with the surface of the ITO, the adhesion with the surface of the ITO used as the anode electrode was improved.

In addition, the luminous efficiency of the organic electroluminescent device is greatly improved by introducing the electron injection layer and the electron transport layer between the light emitting layer and the cathode electrode.

In particular, the following effects can be obtained than conventional PV-based light emitting polymers.

First, it was confirmed that the Spiro-PFV, X₂-Spiro-PFV and PFV derivatives, which introduced spirobiflorenylvinylene derivatives, than the conventional PPV derivatives, were excellent light-emitting polymers.

Second, since the luminescent polymer of the present invention is X₂-Spiro-PFV and PFV derivatives in which aromatic alkyl or alkyloxy substituents are introduced into the side chain of the polymer skeleton, they are very soluble in general organic solvents and have improved heat resistance and interface with electrodes. It is a light emitting polymer with excellent characteristics and very good thin film formation ability.

Third, the luminescent polymer of the present invention has higher glass transition temperature and excellent interfacial characteristics with the electrode due to the introduction of aliphatic alkyl or alkoxy and aromatic substituent at position 9 of the florenylvinylene skeleton. It was found that the thin film formation ability was very good light emitting polymer.

Fourth, the driving voltage of the light emitting polymer of the present invention is about 2.5-7V and emits green-blue, and it can be seen that the change of the EL spectrum according to the operating voltage is much more stable than the conventional poly (florene).

Fifth, the light emitting polymer of the present invention is a polymer having excellent light transmittance, environmental resistance, adhesion to a substrate, thin film formation ability and electric field stability to be provided as an electronic material.

Claims (12)

Polyfluorenyl vinylene derivative consisting of the following formula (1). Formula 1

(Q in Formula 1 is

R is hydrogen or a linear or branched aliphatic alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an aromatic substituent; n is an integer between 10 and 1000) The method of claim 1, Polyfluorenyl vinylene derivative, characterized in that the weight average molecular weight of the polyfluorenyl vinylene derivative is between 5,000 and 1,000,000. The method of claim 1, R in Formula 1 is an aliphatic alkoxy group of 1 to 20, or a polyfluorenyl vinylene derivative, characterized in that an aliphatic alkyl group of 1 to 20 carbon atoms. . The method of claim 1, R in Formula 1 is a C 1-20 branched aliphatic alkoxy group, or a C 1-20 aliphatic alkyl group polyfluorenyl vinylene derivative, characterized in that. The method of claim 1, R in Formula 1 is an aliphatic alkoxy group or octyl group. The method of claim 1, R in Formula 1 is an aromatic substituent selected from benzene, naphthalene, anthracene, toluene, thiophene, dendrimer, polypropylene vinylene derivatives. An organic electroluminescent device comprising a polyfluorenyl vinylene derivative of Formula 1 below. Formula 1

(Q in Formula 1 is

R is hydrogen or a linear or branched aliphatic alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an aromatic substituent; n is an integer between 10 and 1000.) The method of claim 7, wherein The organic electroluminescent device includes an first electrode / light emitting layer / second electrode. The method of claim 8, An organic electroluminescent device further comprising a carrier transport layer and an injection layer between the first electrode and the second electrode. The method of claim 9, An organic electroluminescent device using polythiophene and polyaniline derivatives, which are conductive polymers, as a hole transport layer between the first electrode and the light emitting layer. The method of claim 9, An organic electroluminescent device using Al metal complex derivatives such as Alq ₃ and BAlq ₃ as electron transfer layers between the light emitting layer and the second electrode. The method of claim 11, An organic electroluminescent device using LiF, BaF ₂ or the like as an electron injection layer between the electron transport layer and the second electrode.

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