JP2000072750A - 8-quinolinol derivative and its production and metal complex and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new 8-quinolinol derivative capable of forming a 8- quinolinol derivative complex emitting light having a changed color, having improved heat resistance and oxidation resistance, capable of enhancing the electron-accepting property of the complex and useful as a luminous material for organic thin film electroluminescent elements, etc., by replacing the hydrogen of a 8-quinolinol compound at a specific position by fluorine atom. SOLUTION: A compound of formula I [R is H, a 1-6C alkyl, acetyl or tosyl; (m) and (n) are each 0, 1, 2 or 3; (m)+(n)>=1; when (m)+(n)=1, F is bonded to the 2, 3, 4 or 6-position), for example, 6-fluoro-8-quinolinol. The above compound is obtained by subjecting a 3-nonsubstituted-2-aminophenol compound of formula II and an acrolein compound of formula III (A1 and A2 are each H or F) to a condensation ring-closing reaction in the aqueous solution of phosphoric acid and/or arsenic acid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a fluorine-substituted 8-quinolinol derivative and a method for producing the same. Fluorine substitution 8
The quinolinol derivative is itself useful as a pharmaceutical or an agricultural chemical intermediate, and a metal complex obtained by coordinating the metal with a metal is used as a light emitting material and an electron transporting material for an organic thin film electroluminescence (EL) device. It is useful as an electrophotographic photosensitive member. The present invention also relates to this metal complex and a method for producing the same, a light emitting material for an organic thin film EL device comprising the metal complex, and an organic EL device having a thin film of the metal complex.

[0002]

2. Description of the Related Art 8-Quinolinol (also called oxine or 8-hydroxyquinoline) has a pyridine ring type nitrogen atom and a phenol type hydroxyl group in the molecule, and has a three-dimensional structure which is easily coordinated with a metal atom. -1
It acts as a divalent bidentate ligand and forms stable chelate complexes with almost all divalent or trivalent metal ions. Since many of these metal complexes are hardly soluble in water and soluble in organic solvents, it is well known that this property is used for separating and quantifying metals using this property.

[0003] An 8-quinolinol derivative in which a hydrogen atom on an aromatic ring of 8-quinolinol is substituted has the same complex-forming ability. As the 8-quinolinol derivative, a compound in which the substituent is an alkyl group or a halogen atom (eg, chlorine or fluorine) has been reported so far, and a part thereof is commercially available.

The metal complex of 8-quinolinol, and especially the aluminum complex, was proposed by Tang et al. In 1987 as the first organic thin film EL device using Appl. Phys. Lett., 51, 913.
Has been attracting attention as a light emitting material for organic thin film EL.

The organic thin film EL device has a structure including a light emitting layer made of a fluorescent organic compound and having a thin film having an electron or hole transport function sandwiched between an anode and a cathode. Injection and holes are injected, and electrons and holes are recombined in the light emitting layer to generate excitons (excitons), and the emission of light when the excitons are deactivated is utilized.

[0006] The thin film is a laminate of a light emitting layer and a hole transport layer when the light emitting layer has an electron transporting ability, and is a laminate of the light emitting layer and the electron transporting layer when the light emitting layer has a hole transporting ability. If the body and the light emitting layer can transport both electrons and holes,
A laminate of an electron transport layer / a light emitting layer / a hole transport layer can be used.

The features of the organic thin-film EL element include low-voltage driving, high luminance, and multicoloring. For high brightness and multicolor, a method of doping a fluorescent dye is mainly used. Also, as an attempt to make the device full color,
There are methods of patterning RGB materials, combining white light and a color filter, combining blue light and a light conversion layer, and the like.

Regarding the improvement of the EL emission characteristics of the 8-quinolinol metal complex, for example, when an aluminum complex of 8-quinolinol is doped with a small amount of a suitable organic dye (eg, quinacridone dye), a high luminance of 10 ⁴ cd / m ² is obtained. There is a report that can be obtained.

JP-A-6-145146 discloses a metal complex of an 8-quinolinol derivative substituted with a fluorine atom or a cyano group with various metals, which is useful as an EL light-emitting material. It describes that yellow to orange luminescence is obtained depending on the type.

[0010]

The current doping is
Since the fluorescent dye is deposited simultaneously with the electron transporting material or the hole transporting material, it is troublesome and uniform doping is difficult. In addition, there is a problem in each method of full color. Specifically, in the method of patterning RGB, it is necessary to deposit each of RGB, and there is no excellent red material. In the method of combining white light and a color filter, it is necessary to combine several kinds of light emitting materials in order to obtain white light, and it is difficult to optimize the method. The method of combining the blue light and the light conversion layer does not provide sufficient luminance.

Further, the 8-quinolinol metal complex as an EL light emitting material has durability, particularly heat resistance.
Oxidation resistance is insufficient, and it is required to further improve electron acceptability in order to enhance electrical characteristics.

[0012]

Means for Solving the Problems The present inventors have conducted research on a light emitting material capable of changing the color tone by doping. As a result, the hydrogen at a specific position of a certain 8-quinolinol metal complex is replaced with fluorine. It has been found that the color change is changed by the substitution. Further, since a fluorine atom has a high bond energy with a carbon atom, improvement of heat resistance and oxidation resistance of the molecule can be expected by substitution with the fluorine atom. Further, since fluorine atoms have a high electron-withdrawing property, an effect of enhancing electron-accepting properties can be expected.

However, there are very few kinds of compounds in which the 8-quinolinol derivative is substituted with fluorine, and there are only commercially available compounds in which the fluorine is substituted in the 5-position. There is only.

The above-mentioned JP-A-6-145146 discloses, for example, compounds in which a fluorine atom is monosubstituted at each of the 2- to 7-positions of 8-quinolinol, and 3,6- or 5,7-disubstituted compounds. A metal complex of the compound is shown. As an actual synthesis example of the metal complex, a commercially available 5-substituted fluorine-substituted product
(I.e., 5-fluoro-8-quinolinol) has only been reacted with a metal.

The fluorine-substituted aromatic compound is obtained by diazotizing an aromatic amino compound obtained by reducing an aromatic nitro compound in the presence of tetrafluoroboronic acid by a Bartz-Sieman reaction, and obtaining the resulting tetrafluoroboric acid. It is generally synthesized by introducing a fluorine group by thermally decomposing a diazonium salt. However, it is difficult for this method to selectively proceed with high yield in the case of fluorination of 8-quinolinol. Therefore, at present, a fluorine-substituted derivative of 8-quinolinol cannot be practically used except for a 5-fluorosubstituted derivative described in JP-A-6-145146.

According to the present invention, in the synthesis of 8-quinolinol by the condensation reaction of 2-aminophenol (= o-aminophenol) and acrolein (= acrylaldehyde) using an acid catalyst, one or both reaction components are used. By using a fluorine-substituted derivative as above, an 8-quinolinol derivative in which various positions other than the 2-position are substituted with fluorine can be synthesized.

The condensation reaction between 2-aminophenol and acrolein has conventionally had a problem of low yield, but it has been found that the use of an aqueous solution of phosphoric acid or arsenic acid as a solvent significantly improves the yield. Among the obtained fluorine-substituted 8-quinolinol derivatives, those other than 5- or 7-monofluorinated derivatives are novel compounds.

A fluorine-substituted 8-quinolinol derivative in which various positions including the 2-position are substituted by fluorine is a corresponding halogenated derivative in which a halogen other than fluorine (eg, chlorine) is bonded to the fluorine position. It was also found that by using the raw material as a starting material and substituting the halogen with fluorine by a fluorine substitution reaction, the compound can be synthesized in a sufficient yield.

According to the present invention, a fluorine-substituted 8-quinolinol derivative represented by the following general formula (1) and a method for producing the same are provided. In the general formula (1), R is H, C ₁ -C ₆ alkyl group, a acetyl group or a tosyl group (= p-toluenesulfonyl group); m and n are respectively independently 0 or an integer of 1 to 3 Yes; m + n ≧ 1. When m + n = 1 among these compounds, the compound in which F is bonded to the 2, 3, 4, or 6 position is a novel compound.

[0020]

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According to the present invention, a 2-aminophenol compound unsubstituted at the 3-position represented by the following general formula (2) is further substituted with an acrolein compound represented by the following general formula (3):
A method for producing an 8-quinolinol derivative represented by the above general formula (1), wherein one or more positions other than the 2-position are substituted with fluorine, wherein the reaction is carried out in an aqueous solution of phosphoric acid and / or arsenic acid. Is also provided.

[0022]

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In the above formula, R is H, C ₁ -C ₆ alkyl, acetyl or tosyl; n is 0 or 1-3
A1 and A2 are independently of each other H or F
And n is not 0 when A1 and A2 are both H.

The fluorine-substituted 8-compound represented by the above general formula (1)
The quinolinol derivative can also be produced by a fluorine substitution reaction of a corresponding compound represented by the following general formula (4) in which another halogen is bonded at the position of a fluorine atom.

[0025]

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In the formula, R, m and n have the same meanings as described above, X is selected from chlorine, bromine and iodine, and when m + n ≧ 2, each X may be the same or different. According to this method, an 8-quinolinol derivative substituted at the 2-position with fluorine can also be produced.

The fluorine-substituted 8-quinolinol derivative produced by the method according to the present invention has the ability to form a chelate as a bidentate ligand, similarly to unsubstituted 8-quinolinol, and has various divalent or trivalent properties. Coordinates to a valent metal to form a metal complex.

According to the present invention, a metal complex having a fluorine-substituted 8-quinolinol derivative represented by the following general formula (5) as a ligand is also provided. In the general formula (5), m and n
Has the same meaning as described above, M is a divalent or trivalent metal, and p is 0 (when M is a divalent metal) or 1 (when M is a trivalent metal). Among these metal complexes, those whose ligands are other than 5-fluoro-8-quinolinol are novel compounds.

[0029]

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Such a metal complex can be produced by reacting a fluorine-substituted 8-quinolinol derivative represented by the general formula (1) with a suitable divalent or trivalent metal compound.

According to the present invention, the above-mentioned fluorine-substituted 8-
A luminescent material for an organic thin-film EL device comprising a quinolinol metal complex (preferably M is a trivalent metal, and therefore p is 1), an anode, a hole transport layer comprising an organic compound, and the fluorine-substituted 8-quinolinol metal complex (preferably Also provided is an organic thin-film EL device having a structure in which a light-emitting / electron transport layer composed of M is a trivalent metal and p is 1) and a cathode are sequentially laminated.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION The 8-quinolinol derivative according to the present invention is, as shown in the general formula (1), an 8-quinolinol derivative in which at least one hydrogen atom on the aromatic ring of 8-quinolinol is substituted by fluorine. It is a quinolinol derivative. In the case of the monofluorine-substituted derivative of m + n = 1, a compound having a fluorine bonding position of 2, 3, 4, or 6 is a novel compound.

This compound is produced by a ring-closing reaction by condensation of an unsubstituted 2-aminophenol compound represented by the general formula (2) and an acrolein compound represented by the general formula (3). And at least one of the two reaction components is substituted with fluorine. By this method, a known 8-quinolinol derivative in which the 5- or 7-position of 8-quinolinol is monofluorinated can also be produced. When the starting 2-aminophenol compound (2) is substituted with fluorine, n is 1 in the general formula (1).
To 3 are obtained, and the raw material acrolein compound (3)
When m is 1 or 2 in the general formula (1),
Is obtained.

First, a method for producing the fluorine-substituted 8-quinolinol derivative will be described. Among the reaction components, a 2-aminophenol compound is a compound represented by the above general formula (2), and the 3-position is unsubstituted. That is, fluorine can be substituted at any one to three of the meta and para positions with respect to the amino group (NH ₂ ).
However, when the reaction partner acrolein has fluorine, it may not be substituted with fluorine. The R group is hydrogen, an alkyl group having 6 or less carbon atoms, an acetyl group or a tosyl group.

Among these 2-aminophenol compounds, unsubstituted 2-aminophenol (= o-aminophenol) is commercially available. Fluorine-substituted 2-aminophenol (eg, 5-fluoro-2-aminophenol)
Can be easily synthesized, for example, by reducing the corresponding fluorine-substituted 2-nitrophenol (eg, 5-fluoro-2-nitrophenol). Fluoro-substitutes other than the 5-position can be similarly synthesized. The compound in which the R group is other than H can be obtained by reacting the compound in which the R group is H with a corresponding halide represented by, for example, RX (X is a halogen, preferably chlorine). . When the R group is an alkyl group, other alkylating agents such as dialkyl sulfate and trialkyl phosphate can be used.

Another reaction component to be condensed with the 2-aminophenol compound is an acrolein compound represented by the general formula (3). This compound is acrolein itself or an acrolein derivative in which the α- and / or β-positions are substituted with fluorine (ie, at least one of A1 and A2 is fluorine). The fluorinated acrolein derivative can be synthesized, for example, by a ring-opening reaction of chlorofluorocyclopropane.

The reaction between the compounds (2) and (3) is a condensation reaction between an amine and an aldehyde. This condensation reaction is generally performed in a solvent composed of an acidic aqueous solution. As the acidic aqueous solution, a strong acid such as hydrochloric acid or sulfuric acid is generally used.However, in the condensation reaction of the reaction components (2) and (3) used in the present invention, when these acids are used as a solvent, The reaction does not proceed well and the yield is remarkably low, or a tar-like substance is formed, and the desired product cannot be obtained. It is considered that the acrolein compound is polymerizable, and the polymerization is likely to proceed by heating in a strongly acidic aqueous solution such as hydrochloric acid or sulfuric acid, so that the condensation reaction does not effectively proceed.

On the other hand, when an aqueous solution of phosphoric acid or arsenic acid, which is a weak acid, is used as the reaction solvent, the condensation reaction between the 2-aminophenol compound and the acrolein compound effectively proceeds, and the desired compound represented by the general formula (1) It has been found that the 8-quinolinol derivative represented by the formula can be produced in good yield. However, when acetic acid, which is an organic acid, is used even for a weak acid, a high yield cannot be obtained for unknown reasons.

A particularly preferred reaction solvent is a phosphoric acid aqueous solution, but an arsenic acid aqueous solution can also be used, or a mixed aqueous solution of phosphoric acid and arsenic acid can be used. The concentration of the aqueous solution is 30 for phosphoric acid
8585 wt%, and in the case of arsenic acid, the range is preferably 30-60 wt%.

The reaction is preferably carried out in the presence of an oxidizing agent centering on a nitro compound and a small amount of a catalyst such as iron sulfate, as conventionally performed. The nitro compound as the oxidizing agent is not particularly limited, but m-nitrobenzenesulfonic acid, nitrobenzene and the like are generally used.

The reaction temperature and reaction time are not particularly limited, but the reaction is generally carried out at 70 to 150 ° C, preferably 80 to 110 ° C. The reaction does not proceed effectively below 70 ° C,
In the above, the progress of side reactions increases, and a tar-like substance is generated, and it is difficult to synthesize the target substance substantially effectively. Although the reaction time is not particularly limited, it is generally 0.5 to 8
This is performed for a time, preferably 1 to 4 hours.

The reaction is generally carried out by dissolving a 2-aminophenol derivative, a nitro compound, iron sulfate or the like in an aqueous acid solution of a solvent and dropping an acrolein compound or a solution thereof into the resulting solution. Is also possible.

After completion of the dropwise addition, the reaction is carried out while maintaining the reaction temperature for a predetermined time. The reaction product can be isolated by neutralizing the reaction solution and purifying the resulting precipitate by direct distillation (or sublimation), or by extracting with a suitable solvent and then distilling. By this method, one of the 3rd to 7th positions is
An 8-quinolinol derivative substituted at one or more positions with fluorine can be obtained in good yield. Among them, compounds other than 5- or 7-monofluorinated 8-quinolinol are novel compounds.

According to another method according to the invention, the general formula
The fluorinated 8-quinolinol derivative of the present invention represented by (1) is produced by a fluorine substitution reaction of the corresponding halogenated derivative other than fluorine represented by the general formula (4). As the halogen other than fluorine, any of chlorine, bromine and iodine can be used.

In this reaction, K is used as a fluorine-substituted reactant.
This is generally performed by using an alkali metal fluoride such as F or CsF. It is preferable to use both KF and CsF in combination. In this case, KF may be used as a main agent in an equivalent amount or more, and CsF may be used in a small amount as a reaction accelerator. In order for this reaction to proceed effectively, when the R group is H, the R group is substituted with an alkoxy group or an acetyl group to form OH
It is desirable to keep the group protected. Further, it is preferable that the ring nitrogen atom of the quinoline ring be an N-oxide.
The method of N-oxidation is not particularly limited, but peracetic acid or the like is generally used.

As a solvent for the fluorine substitution reaction, sulfolane, N-methylpyrrolidone, DMSO or the like is used.
Generally, both the solvent and the fluorine-substituted reactant must be sufficiently dried. The reaction temperature is preferably 100 to 250 ° C, and the reaction time is usually about 1 to 15 hours.

According to this fluorine substitution reaction, a fluorine group can be introduced at any position of 8-quinolinol,
Therefore, an 8-quinolinol derivative in which the 2-position is substituted by fluorine, which cannot be produced by the first method, can also be synthesized.

The fluorine-substituted 8-quinolinol derivative synthesized by any of the above methods has the same complex-forming ability as 8-quinolinol, and can form a complex with various metals. As the metal, any of a monovalent alkali metal and a polyvalent metal is possible, but a polyvalent metal is preferable. In particular, trivalent metals such as Al, Ga, and In, which are attracting attention as light emitting materials for EL elements, are preferable. But,
It can also form a complex with divalent metals such as Zn and Be.

The structure of the metal complex in which the fluorine-substituted 8-quinolinol derivative according to the present invention is coordinated to a divalent or trivalent metal is as shown in the above-mentioned general formula (5). General formula (5)
As shown in the above, trivalent metals are tri-coordinated (that is, the general formula
In (5), a bivalent metal complex (that is, p is 0 in the general formula (5)) is formed with a divalent metal with a divalent metal.

This metal complex is easily formed when 8-quinolinol is reacted with a suitable metal compound (eg, a divalent or trivalent metal compound) in an organic solvent. The metal compound may be soluble in the organic solvent used, for example, an alkylated metal compound (eg, triethylaluminum)
Alternatively, a halide such as aluminum chloride may be used. Examples of the solvent include hydrocarbons such as toluene and ethers such as tetrahydrofuran.
However, it is not limited to this.

The complex formation reaction is carried out, for example, by using an inert gas.
In an atmosphere (eg, nitrogen), the 8-quinolinol derivative can be dissolved in an anhydrous organic solvent, and an organic solvent solution of the metal compound can be added dropwise to the resulting solution using a syringe.
The reaction temperature and reaction time are not particularly limited, but the reaction temperature is preferably room temperature to 50 ° C, and the reaction time will be about 3 to 10 hours.

The structures of the fluorine-substituted 8-quinolinol derivative of the present invention and the metal complex to which it is coordinated can be confirmed by MS (mass spectrum), elemental analysis, IR, NMR and the like. In particular, the measurement of the molecular weight by MS makes a large judgment on whether or not the target substance is generated.

The fluorine-substituted 8-quinolinol metal complex (metal M is preferably a trivalent metal, particularly preferably Al) according to the present invention is useful as a light emitting layer material of an organic thin film EL device. Since this metal complex exhibits electron conductivity, it can also function as an electron transporting material in addition to the function as a light emitting material. Therefore, an organic thin film EL device using this metal complex has a structure in which an anode, a hole transport layer made of an organic compound, a light emitting / electron transport layer made of this fluorine-substituted 8-quinolinol metal complex, and a cathode are sequentially laminated. Usually, this laminated film is formed on a substrate.

As the substrate, besides glass, a transparent resin such as polyethylene can be used. First, a transparent electrode is formed as an anode on this substrate. The anode is, for example, I
It may be made of TO (indium tin oxide) or the like, and may be formed by a method such as evaporation or sputtering. On this anode, a film is formed by, for example, vacuum evaporation in the order of a hole transport material, a light-emitting / electron transport material (the fluorine-substituted 8-quinolinol metal complex of the present invention), and a cathode. As the hole transporting material, an amine-based, hydrazine-based, stilbene-based, or other organic compound can be used. As the cathode, an alkali metal, an alkaline earth metal, or the like can be used. Since the total thickness of the organic layer is as thin as about 100 nm, low-voltage driving is possible.

[0055]

【Example】

[0056]

Example 1 In a 200 ml three-necked flask equipped with a magnetic stirrer, a reflux condenser, a thermometer, and a dropping funnel, 10.0 g of 2-amino-5-fluorophenol, 8.3 g of m-nitrobenzenesulfonic acid as an oxidizing agent, and a solvent were used. 50 ml of 85wt% phosphoric acid aqueous solution,
Then, 0.1 g of ferrous sulfate as a catalyst was added, and the mixture was heated to 80 ° C. in an oil bath. Subsequently, 10 ml of acrolein was added dropwise from the dropping funnel over 1 hour. After completion of the dropwise addition, the mixture was heated and stirred at 100 ° C. for 2 hours to be reacted. Thereafter, the reaction solution was poured into water and neutralized to pH 7 with aqueous ammonia. The neutralized solution was extracted with dichloromethane, then dichloromethane was removed under reduced pressure, and the remaining brown solid was directly purified by sublimation under reduced pressure to give 6
4.3 g of a white solid of -fluoro-8-quinolinol was obtained.

DI-MS (direct mass spectrum) Fragment: 163 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 66.3, H 3.7, N 8.6, F 11.7 Actual value: C 66.9, H 3.5, N 8.3, F 12.2

[0058]

Example 2 By the same operation as in Example 1, 6.0 g of 2-amino-5,6-difluorophenol, 4.4 g of m-nitrobenzenesulfonic acid, 50 ml of 85 wt% phosphoric acid aqueous solution, 0.1 g of ferrous sulfate and Using 10 ml of acrolein,
4.5 g of 6,7-difluoro-8-quinolinol white solid
I got

DI-MS fragment: 181 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 59.7, H 2.8, N 7.7, F 21.0 Actual value: C 59.4, H 2.4, N 7.6,
F 21.8

[0060]

Example 3 By the same operation as in Example 1, 7.0 g of 2-amino-4,5,6-trifluorophenol, 5.0 g of m-nitrobenzenesulfonic acid, 50 ml of an 85 wt% phosphoric acid aqueous solution
Using 0.1 g of ferrous sulfate and 10 ml of acrolein, 4.1 g of a white solid of 5,6,7-trifluoro-8-quinolinol was obtained.

DI-MS fragment: 199 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 54.3, H 2.0, N 7.0, F 28.6 Actual value: C 54.9, H 2.1, N 7.2, F 29.1

[0062]

Example 4 By the same operation as in Example 1, 10.0 g of 2-aminophenol and 6.0 g of m-nitrobenzenesulfonic acid were obtained.
g, 50 ml of a 85 wt% phosphoric acid aqueous solution, 0.1 g of ferrous sulfate and 10 ml of α-fluoroacrolein to obtain 4.1 g of 3-fluoro-8-quinolinol as a white solid.

DI-MS fragment: 163 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 66.3, H 3.7, N 8.6, F 11.7 Actual value: C 66.6, H 3.2, N 8.6, F 12.2

[0064]

Example 5 By the same operation as in Example 1, 10.0 g of 2-amino-5-fluorophenol, 6.5 g of m-nitrobenzenesulfonic acid, 50 ml of 85 wt% phosphoric acid aqueous solution, 0.1 g of ferrous sulfate and α- Using 10 ml of fluoroacrolein, a white solid of 3,6-difluoro-8-quinolinol
4.1 g were obtained.

DI-MS fragment: 181 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 59.7, H 2.8, N 7.7, F 21.0 Actual value: C 60.2, H 2.7, N 7.5, F 21.7

[0066]

Example 6 6-Fluoro-8-quinolinol was synthesized in exactly the same manner as in Example 1 except that 50 ml of a 50 wt% arsenic acid aqueous solution was used as a solvent instead of the 85 wt% phosphoric acid aqueous solution. The product was obtained as a white solid, 3.8 g.

DI-MS fragment: 163 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 66.3, H 3.7, N 8.6, F 11.7 Actual value: C 66.5, H 3.6, N 8.4, F 11.9 In each of the above examples, the R group of 2-aminophenol (2) is H. However, even when the R group is a lower alkyl group other than H, an acetyl group or a tosyl group, the same applies to the above. It will be understood by those skilled in the art that the corresponding fluorine-substituted derivatives can be synthesized by Alternatively, it will be appreciated by those skilled in the art that compounds of the present invention wherein the R group is other than hydrogen can be synthesized by reacting the products of Examples 1-6 with a suitable alkylating, acetylating or tosylating agent. If you can understand it.

[0068]

Example 7 2-Chloro-8- was placed in a 200 ml eggplant-shaped flask.
Methoxyquinoline 10.0 g, dried sulfolane 50 ml,
10.0 g of KF and 2.0 g of CsF were added and reacted by heating and stirring at 200 ° C. for 12 hours. Thereafter, the reaction solution was poured into water, and the precipitated precipitate was separated by filtration and directly purified by sublimation under reduced pressure to obtain 4.3 g of 2-fluoro-8-methoxyquinoline as a white solid.

DI-MS fragment: 177 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 67.8, H 4.5, N 7.9, F 10.7 Actual value: C 67.0, H 4.9, N 7.5, F 11.2

[0070]

Example 8 4-Chloro-8- was placed in a 200 ml eggplant-shaped flask.
Methoxyquinoline 10.0 g, dried sulfolane 50 ml,
10.0 g of KF and 3.0 g of CsF were added, and reacted by heating and stirring at 200 ° C. for 12 hours. Thereafter, the reaction solution was poured into water, and the deposited precipitate was separated by filtration and directly purified by sublimation under reduced pressure to obtain 4.5 g of 4-fluoro-8-methoxyquinoline as a white solid.

DI-MS fragment: 177 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 67.8, H 4.5, N 7.9, F 10.7 Actual value: C 67.4, H 4.4, N 7.7, F 10.3 In the above examples, a fluorine-substituted 8-quinolinol derivative in which the R group of the general formula (1) is a methoxy group was synthesized.
This is hydrolyzed by a conventional method to obtain a corresponding compound in which the R group is H. The compound is further reacted with an appropriate alkylating agent, acetylating agent or tosylating agent to obtain an R group. Can synthesize compounds other than hydrogen.

[0072]

Comparative Example 1 The same operation as in Example 1 was performed except that concentrated hydrochloric acid was used as a solvent. A tar-like substance was produced, and the desired product was not obtained.

[0073]

Comparative Example 2 The same operation as in Example 1 was performed except that concentrated sulfuric acid was used as a solvent. A tar-like substance was produced, and the desired product was not obtained.

[0074]

Comparative Example 3 8-quinolinol was nitrated and then reduced to synthesize 5,7-diaminoquinolinol. Subsequently, according to a conventional fluorination method, after diazotization using sodium nitrite and an aqueous solution of borofluoric acid, synthesis of a difluoro compound was attempted by thermally decomposing the diazotized product, but tar-like substances were found. The desired product was not obtained just by producing.

[0075]

Example 9 A 200-ml four-necked flask equipped with a magnetic stirrer, a reflux condenser, a thermometer, and a silicon stopper was placed under a nitrogen atmosphere.
0.55 g of 6-fluoro-8quinolinol was dehydrated in THF 60 m
solution was introduced into the flask from a silicon stopper with a syringe, and 0.91M of triethylaluminum was further added.
1.25 ml of a toluene solution was similarly placed in the flask. Thereafter, the reaction mixture was stirred at room temperature for 5 hours, and the precipitated crystals were separated by filtration, washed with THF, dried under reduced pressure, and dried.
0.4 g of a fluorine-substituted 8-quinolinol aluminum complex [tris (6-fluoro-8-quinolinolato) aluminum] having three molecules of fluoro-8-quinolinol coordinated to one atom of Al was obtained.

DI-MS fragment: 513 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 63.2, H 2.9, N 8.2, F 11.1 Actual value: C 63.5, H 2.7, N 8.4, F 10.9

[0077]

Example 10 In the same manner as in Example 9, 0.61 g of 6,7-difluoro-8-quinolinol was reacted with triethylaluminum to give a tricoordinate aluminum complex [tris (6,7-difluoro-8-). (Quinolinolato) aluminum] 0.45 g was obtained.

DI-MS fragment: 567 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 57.1, H 2.1, N 7.4, F 20.1 Actual value: C 57.3, H 2.3, N 7.2, F 19.9

[0079]

[Embodiment 11] By the same operation as in Embodiment 9, 5, 6, 7-
Reaction of 0.67 g of trifluoro-8-quinolinol with triethylaluminum to form a three-coordinate aluminum complex
[Tris (5,6,7-trifluoro-8-quinolinolato) aluminum] 0.55 g was obtained.

DI-MS fragment: 621 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 52.2, H 1.4, N 6.8, F 27.5 Actual value: C 52.4, H 1.5, N 6.6, F 27.3

[0081]

Example 12 In the same manner as in Example 9, 0.55 g of 3-fluoro-8-quinolinol was reacted with triethylaluminum to form a three-coordinate aluminum complex [Tris
(3-Fluoro-8-quinolinolato) aluminum] 0.4
1 g was obtained.

DI-MS fragment: 513 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 63.2, H 2.9, N 8.2, F 11.1 Actual value: C 63.3, H 2.8, N 8.3, F 10.9

[0083]

Example 13 In the same manner as in Example 9, 0.61 g of 3,6-difluoro-8-quinolinol was reacted with triethylaluminum to give a tricoordinated aluminum complex [tris (3,6-difluoro-8-). (Quinolinolato) aluminum] 0.43 g was obtained.

DI-MS fragment: 567 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 57.1, H 2.1, N 7.4, F 20.1 Actual value: C 57.0, H 2.2, N 7.3, F 19.9

[0085]

Example 14 In the same manner as in Example 9, 0.55 g of 2-fluoro-8-quinolinol was reacted with triethylaluminum to form a tricoordinate aluminum complex [Tris
(2-fluoro-8-quinolinolato) aluminum] 0.3
9 g were obtained.

DI-MS fragment: 513 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 63.2, H 2.9, N 8.2, F 11.1 Actual value: C 63.1, H 2.8, N 8.4, F 11.0

[0087]

Example 15 In the same manner as in Example 9, 0.55 g of 7-fluoro-8-quinolinol was reacted with triethylaluminum to form a tricoordinate aluminum complex [Tris
(7-fluoro-8-quinolinolato) aluminum] was obtained.

DI-MS fragment: 513 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 63.2, H 2.9, N 8.2, F 11.1 Actual value: C 63.3, H 2.8, N 8.0, F 11.0

[0089]

Example 16 In the same manner as in Example 9, 0.55 g of 4-fluoro-8-quinolinol was reacted with triethylaluminum to form a tricoordinate aluminum complex [Tris
(4-Fluoro-8-quinolinolato) aluminum] was obtained.

DI-MS fragment: 513 (M ⁺ ) Elemental analysis result (unit: wt%) Theoretical value: C 63.2, H 2.9, N 8.2, F 11.1 Actual value: C 63.1, H 2.8, N 8.1, F 11.3

[0091]

Embodiment 17 A glass substrate with a cleaned ITO film (IT
O film thickness: 140 to 160 nm, surface resistance: 20Ω / □), and N, N′-diphenyl-N, N′-di (m-tolyl) benzidine (TPD) as a hole transport material by vacuum evaporation The film was formed with a thickness of 50 nm. A tris (6-fluoro-8-quinolinolato) aluminum complex obtained in Example 9 was deposited thereon as a light-emitting / electron transporting material to a thickness of 50 nm by vacuum evaporation. Finally, Mg and Ag were used as cathode materials. 150 nm by co-evaporation
An organic EL device was manufactured by forming a film with a large thickness. The degree of vacuum is 10
It was of the order of ^-4 Pa. The luminance and chromaticity of this element
Table 1 shows the results of measurement using a luminance meter BM-7 manufactured by PCON.

[0092]

Example 18 An organic EL device was produced in the same manner as in Example 17 except that the tris (6,7-difluoro-8-quinolinolato) aluminum complex obtained in Example 10 was used as a light emitting / electron transporting material. . The brightness and chromaticity of this element
Table 1 shows the results of measurement using a luminance meter BM-7.

[0093]

Example 19 An organic EL device was produced in the same manner as in Example 17 except that the tris (7-fluoro-8-quinolinolato) aluminum complex obtained in Example 15 was used as a light emitting / electron transporting material. Table 1 shows the results obtained by measuring the luminance and chromaticity of this device with a luminance meter BM-7 manufactured by TOPCON.

[0094]

Example 20 An organic EL device was produced in the same manner as in Example 17, except that the tris (3-fluoro-8-quinolinolato) aluminum complex obtained in Example 12 was used as a light emitting / electron transporting material. Table 1 shows the results obtained by measuring the luminance and chromaticity of this device with a luminance meter BM-7 manufactured by TOPCON.

[0095]

Example 21 An organic EL device was produced in the same manner as in Example 17, except that the tris (4-fluoro-8-quinolinolato) aluminum complex obtained in Example 16 was used as a light emitting / electron transporting material. Table 1 shows the results obtained by measuring the luminance and chromaticity of this device with a luminance meter BM-7 manufactured by TOPCON.

[0096]

Comparative Example 4 An organic EL device was manufactured in the same manner as in Example 17 except that a tris (8-quinolinolato) aluminum complex not substituted with fluorine was used as a light emitting / electron transporting material. The brightness and chromaticity of this element are measured by TOPCON brightness meter BM.
Table 1 shows the results measured at -7.

[0097]

Comparative Example 5 Known tris as a light emitting / electron transporting material
(5-Fluoro-8-quinolinolato) An organic EL device was produced in the same manner as in Example 17, except that an aluminum complex was used. The brightness and chromaticity of this element are measured by TOPCON brightness meter BM-7.
Table 1 shows the results of the measurement.

[0098]

[Table 1]

As can be seen from Table 1, the emission color could be changed by replacing the hydrogen atoms at various positions of the tris (8-quinolinolato) aluminum complex, which emits green light without substitution, with fluorine atoms. This makes it possible to manufacture a multicolor display. Further, an emission color close to white can be obtained with a single material, and application to a full-color display is also possible.

[0100]

According to the present invention, a fluorine-substituted 8-quinolinol derivative having excellent durability, especially heat resistance and oxidation resistance,
Metal complexes having these as ligands can be synthesized with high yield.
The obtained fluorine-substituted 8-quinolinol derivative is
It is extremely useful as an intermediate for pesticides and the like. Further, a fluorine-substituted 8-quinolinol metal complex having this as a ligand is
It is extremely useful as an electron transporting material or a light emitting material for an EL device, an electron transporting material for an electrophotographic photosensitive member, and the like.

In particular, the metal complex has excellent durability due to the introduction of fluorine, and the emission color changes depending on the position of substitution of fluorine, so that a multicolor display can be manufactured. Further, since a single material can emit a color near white, application to a full-color display can be considered.

Claims (7)

[Claims] 1. A fluorine-substituted 8-quinolinol derivative represented by the following general formula (1). Embedded image Herein, R is H, C ₁ -C ₆ alkyl group, an acetyl group or be a tosyl group; be m + n ≧ 1;; m and n are each independently 0 or an integer of 1 to 3 m + n =
When 1, the bonding position of F is 2, 3, 4 or 6. 2. A 2-aminophenol compound having a 3-position unsubstituted compound represented by the following general formula (2) and an acrolein compound represented by the following general formula (3) in an aqueous solution of phosphoric acid and / or arsenic acid: A method for producing an 8-quinolinol derivative in which one or more positions other than the 2-position has been substituted with fluorine. Embedded image Herein, R is H, C ₁ -C ₆ alkyl group, a an acetyl group or a tosyl group,; n is 0 or an integer from 1 to 3; A1 and A2 is H or F independently of one another, A1
When A and A2 are both H, n is not 0. 3. The fluorine-substituted 8-quinolinol derivative according to claim 1, which is produced by a fluorine-substitution reaction of a corresponding halogen compound in which another halogen is bonded at the position of a fluorine atom. A method for producing a quinolinol derivative. 4. A fluorine-substituted 8 represented by the following general formula (5):
-Metal complexes of quinolinol derivatives. Embedded image Herein, R is H, C ₁ -C ₆ alkyl group, an acetyl group or be a tosyl group; be m + n ≧ 1;; m and n are each independently 0 or an integer of 1 to 3 m + n =
When 1, the bonding position of F is at position 2, 3, 4, 6, or 7, M is a divalent or trivalent metal, and p is 0 or 1. 5. The method according to claim 4, wherein M is a trivalent metal and p is 1.
The metal complex as described. 6. The fluorine-substituted 8- according to claim 4 or 5.
A luminescent material for an organic thin-film electroluminescence device, comprising a metal complex of a quinolinol derivative. 7. An anode, a hole transport layer comprising an organic compound,
An organic thin-film electroluminescence device having a structure in which a light-emitting / electron transport layer comprising a metal complex of the fluorine-substituted 8-quinolinol derivative according to claim 4 or 5 and a cathode are sequentially laminated.