WO2005123652A1

WO2005123652A1 - Rare earth metal complex light-emitting material having aromatic organic ligand

Info

Publication number: WO2005123652A1
Application number: PCT/JP2005/010821
Authority: WO
Inventors: Hideo Suzuki; Ken Endo; Fumio Hamada
Original assignee: Nissan Chemical Industries, Ltd.
Priority date: 2004-06-15
Filing date: 2005-06-14
Publication date: 2005-12-29
Also published as: TW200613313A; JPWO2005123652A1

Abstract

A rare earth metal complex represented by the formula (1) below emits very monochromatic light which is derived from the rare earth metal ions, and provides a light-emitting material having high luminous (quantum) efficiency and excellent durability. [In the formula, M represents La or the like; A represents a benzene ring or the like; R1 represents -COO- group or the like; R2 and R3 independently represent a hydrogen atom, halogen atom or the like; and n and m respectively represent an integer of 1 or more.]

Description

Specification

Rare earth metal complex luminescent material with aromatic organic ligand

Technical field

The present invention relates to a rare earth metal complex light emitting material having an aromatic organic ligand, and more specifically, for example, as a light emitting material for an organic electroluminescent device (hereinafter abbreviated as an EL device) and a light emitting material. The present invention relates to a rare earth metal complex that can be suitably used and a method for producing the same.

Background art

[0002] As a light emitting material of an organic EL device, an organic aluminum complex (Alq) having excellent luminous efficiency and durability has been put to practical use. On the other hand, most of the conventional methods using rare earth metals

Three

The light material is an inorganic light emitting material made of an inorganic compound.

[0003] When a rare-earth metal is directly excited, its energy efficiency is problematic. For this reason, a material that easily absorbs energy is arranged around the rare earth metal, and high efficiency of light emission utilizing energy transfer therefrom has been studied.

For example, in the case of an inorganic light emitting material using a rare earth metal, a method of adding a trace amount of a rare earth metal ion to an inorganic compound mother crystal which easily absorbs energy is mainly used. This inorganic light emitting material has been put to practical use in color televisions and fluorescent lamps.

[0004] When an organic light-emitting material containing a rare earth metal is used, a method of covering the rare earth metal ion with a certain organic ligand (complexation) is generally used (Patent Document 1: Japanese Patent Application Laid-Open No. 2000-2000) — 281618, Patent Document 2: JP 2000-344712, Non-Patent Document l: Jpn. J. Appl. Phys., Vol. 34, 1995, pp. 1883-1887).

Rare-earth organic complexes have (1) increased rare-earth metal ion density and (2) increased monochromaticity due to rare-earth metal ion sequestration compared to inorganic luminescent materials! ], (3) Although improvements in luminous efficiency (quantum yield) are expected, few materials with excellent luminous efficiency have been found at present. There are also many problems in terms of durability (light stability, thermal stability) and workability.

Incidentally, rare earth metal complexes having an organic phosphine carboxylic acid as a ligand have been reported. However, it has been described that this rare earth complex can be used as a light emitting material (Patent Document 1: Japanese Patent Application Laid-Open No. 2002-155095).

Patent Document 1: JP-A-2000-281618

Patent Document 2: JP-A-2000-344712

Patent Document 3: JP-A-2002-155095

Non-Patent Document l: Jpn.J. Appl. Phys., Vol. 34, 1995, pp. 1883-1887

Disclosure of the invention

Problems to be solved by the invention

The present invention has been made in view of such circumstances, and has excellent monochromatic light emission derived from rare earth metal ions, and has high light emission (quantum) efficiency and excellent durability. It is an object of the present invention to provide a rare earth metal complex for providing a material, a method for producing the same, and a light emitting material containing the rare earth metal complex.

Means for solving the problem

[0007] The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, a rare-earth metal complex having an aromatic organic ligand such as a benzene ring or a naphthalene ring shows emission with good monochromaticity. In addition, they have found that they can be a luminescent material having high luminescence (quantum) efficiency and excellent durability, and have completed the present invention.

That is, the present invention provides the following inventions [1] to [3].

[1] A rare earth metal complex represented by the formula (1).

[Chemical 1]

(Wherein, M represents La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc, or Y, and A represents a benzene ring , A naphthalene ring, an anthracene ring, a pyridine ring, a thiophene ring, a furan ring, a pyrazole ring, or an imidazole ring, wherein R ¹ is a —COO— group, —CONH—CH (R ⁴ ) (R ⁴ is Represents an alkyl group of to 10) or —CO ² O—, wherein R ² and R ³ each independently represent a hydrogen atom, a halogen atom, a cyano group, Even if it is substituted with an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkoxycarbyl group having 1 to 10 carbon atoms, a nitro group, an amino group, a hydroxyl group, a —COO— group, or Z A phenyl group, a naphthyl group optionally substituted with Z, a biphenyl group optionally substituted with Z, an anthryl group optionally substituted with Z, a diheteroarylphosphino group, Represents a dialkylphosphino group having 1 to 10 carbon atoms, an alkylarylphosphino group having 1 to 10 carbon atoms, or an alkylheteroarylphosphino group having 1 to 10 carbon atoms (where the aryl group is A phenyl group optionally substituted with Z, a naphthyl group optionally substituted with Z, substituted with Z !, may! /, Substituted with biphenyl group or Z !, / Represents an aryl group, and the heteroaryl group may be substituted with Z. A furyl group, substituted with Z, may be substituted with a virazolyl group or Z, and represents an imidazolyl group.) And Z is a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms Group, an alkoxy group having 1 to 10 carbon atoms, a carbon number of 1 to: represents an alkoxycarboxy group, a nitro group, an amino group, a hydroxyl group, a COO— group, or a phenyl group of LO; Represents an integer of 1 or more. ]

(2) Equation (2)

[Chemical 2]

(Where A,

R ³ and n are the same as above. p represents an integer of 1 or more. )

And an organic ligand sodium salt represented by the formula (3)

[Formula 3]

(Wherein, M and m are the same as above. X represents a halogen ion, nitrate ion, sulfate ion, perchlorate ion, boron tetrafluoride ion, acetate ion, and q represents an integer of 1 or more. (1) characterized by reacting a rare earth metal salt represented by the formula (1) in water.

(Where A,

R ² , R ³ , M, n and m are the same as above. )

A method for producing a rare earth metal complex represented by the formula:

[3] A luminescent material comprising the rare earth metal complex represented by the formula (1).

[Formula 5]-, M ³⁺ ) _M (1)

n

[

n and m are the same as above. R ² and R ³ each independently represent a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, A nitro group, an amino group, a hydroxyl group, a —CO— group, a phenyl group optionally substituted with Z, a naphthyl group optionally substituted with Z, and a biphenyl group optionally substituted with Z. -Aryl group, anthryl group optionally substituted with Z, diarylphosphino group, diheteroarylphosphino group, dialkylphosphino group having 1 to 10 carbon atoms, alkylarylphosphine having 1 to 10 carbon atoms Represents an ino group or an alkylheteroarylphosphino group having 1 to 10 carbon atoms (where the aryl group is a phenyl group which may be substituted with Z, Naphthyl group, may be substituted by Z V ヽ biphenyl group or Z may be substituted with an anthryl group, wherein the heteroaryl group is a furyl group optionally substituted with Z, a pyrazolyl group optionally substituted with Z or substituted with z. Represents an imidazolyl group which may be present), and Z is the same as described above. 〕 The invention's effect

The rare earth metal complex having an aromatic organic ligand of the present invention (and a light-emitting material containing the same) exhibits good monochromatic light emission, has high light-emitting (quantum) efficiency, and is excellent in durability. Therefore, the rare-earth metal complex of the present invention and a luminescent material containing the same include a luminescent layer of an organic EL device, an organic zeolite having a luminescent function, a luminescent adsorbent, a luminescent high-sensitivity molecular sensor, a luminescent high-sensitivity chiral sensor, and a biological material. Suitable for use in applications such as contrast agents and reaction catalysts. It comes out.

Brief Description of Drawings

FIG. 1 is an IR chart of 4 diphenylphosphinobenzoic acid-sodium salt.

FIG. 2 is an IR chart of a 4-diphenylphosphinobenzoic acid-lanthanum complex.

FIG. 3 is an IR chart of a palladium complex of 4-diphenylphosphinobenzoic acid.

FIG. 4 is an IR chart of 4-diphenylphosphinobenzoic acid-terbium complex.

FIG. 5 is an IR chart of 4-diphenylphosphinobenzoic acid-ytterbium complex.

FIG. 6 is an IR chart of 4-diphenylphosphinobenzoic acid-yttrium complex.

FIG. 7 is an IR chart of 4- (4-hydroxyphenyl) benzoic acid sodium salt.

FIG. 8 is an IR chart of a lanthanum 4- (4-hydroxyphenyl) benzoate complex.

FIG. 9 is an IR chart of a mononuclear pium complex of 4- (4-hydroxyphenyl) benzoic acid.

FIG. 10 is an IR chart of a terbium 4- (4-hydroxyphenyl) benzoate complex.

FIG. 11 is an IR chart of ytterbium complex of 4- (4-hydroxyphenyl) benzoic acid.

FIG. 12 is an IR chart of 4- (4-hydroxyphenyl) benzoic acid-yttrium complex.

FIG. 13 is an IR chart of 4 diphenylphosphinobenzoic acid.

FIG. 14 is an IR chart of 4- (4-hydroxyphenyl) benzoic acid.

BEST MODE FOR CARRYING OUT THE INVENTION

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

In the following description, “n” represents normal, “i” represents iso, “s” represents secondary, and “t” represents tertiary.

The rare earth metal complex having an aromatic organic ligand according to the present invention is represented by the above formula (1).

In the formula (1), examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

[0012] C1-C1: The alkyl group of LO may be linear, branched or cyclic, for example, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t Butyl, s-butyl, n-pentyl, n-hexyl, 2-ethylpropyl, 2,2-dimethylpropyl Nole, 1,2-dimethinolepropynole, 1,1,2-trimethinolepropynole, 1,2,2-trimethinolepropyl, 1-ethyl 1-methylpropyl, 1-ethyl 2-methylpropyl, 1-methylbutyl, 2 —Methylbutyl, 3-methylbutyl, 1,1-dimethylbutyl, 1,2-dimethylbutyl, 1,3 dimethylbutyl, 2,2 dimethylbutyl, 2,3 dimethylbutyl, 3,3 dimethylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1-methylpentyl , 2-methylpentyl, 3-methylpentyl, 4-methylpentyl and the like.

[0013] The C-C alkoxy group may be any of linear, branched or cyclic, for example, methoxy.

1 10

Xy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, n-pentyloxy, n-hexyloxy, 1,1-dimethylpropoxy, 1,2-dimethylpropoxy, 2 1,2-dimethylpropoxy, 1-ethylpropoxy, 1,1,2-trimethylpropoxy, 1,2,2-trimethylpropoxy, 1-ethyl-1-methylpropoxy, 1-ethyl-2-methylpropoxy, 1-methylbutoxy, 2-methylbutoxy , 3-methylbutoxy, 1-ethylbutoxy, 2-ethylbutoxy, 1,1-dimethylbutoxy, 1,2 dimethylbutoxy, 1,3 dimethylbutoxy, 2,2 dimethylbutoxy, 2,3 dimethylbutoxy, 3,3 dimethylbutoxy, 1-methyl Pentyloxy, 2-methylpentyloxy, 3-methylpentyloxy and 4-methyl Rupenchiruokishi, and the like.

The C to C alkoxycarbol group may be any of linear, branched or cyclic.

1 10

For example, methoxycarbonyl, ethoxycarbonyl, n-propoxycarbonyl, i-prop-oxycarbonyl, n-butoxycarbonyl, i-butoxycarbonyl, s-butoxycanolevoninole, t-butoxycarbonyl, n-pentyloxycarbonyl, n-hexyloxycarbonyl, 1,1-dimethylpropoxycarbonyl, 1,2-dimethylpropoxycarbonyl, 2,2-dimethinolepropoxycanoleboninole, 1-ethylpropoxycarbonyl, 1,1,2-trimethylpropoxycarbonyl, 1,2,2 —Trimethylpropoxycarbinole, 1-ethynole 1-methinolepropoxycanoleboninole, 1-ethynole 2-methinolepropoxycarbonyl, 1-methylbutoxycarbonyl, 2-methylbutoxycarbonyl, 3-methylbutoxycarbonyl, 1-ethyl Butoxycarbonyl, 2-E chill-butoxy Cal Boniru, 1, -1-dimethyl-butoxycarbonyl, 1, 2-dimethyl-butoxycarbonyl, 1, 3-dimethylbutoxycarbonyl, 2,2-dimethylbutoxycarbonyl, 2,3-dimethylbutoxycarbonyl, 3,3-dimethylbutoxycarbonyl, 1-methylpentyloxycarbonyl, 2-methylpentyloxycarbonyl, 3-methylpentyloxycarbonyl And 4-methylpentyloxycarbol.

Examples of the alkyl group in the dialkylphosphino group having 1 to 10 carbon atoms and the alkylarylphosphino group having 1 to 10 carbon atoms include the same groups as those exemplified above.

[0015] Considering practical availability, the aromatic organic ligand composed of A, R ² and R ³ is a carboxylic acid of 4-diphenylphosphinobenzoic acid (A is a benzene ring). , R ¹ is a —COO— group, R ² is a hydrogen atom, R ³ is a diphenylphosphino group), 4- (4-hydroxyphenyl) benzoic acid carboxylic acid ion (A is a benzene ring, R ¹ is —COO— group, R 2 is a hydrogen atom, R ³ is a hydroxyphenyl group) and the like.

Considering practical availability, La, Eu, Tb, and Yb are preferred for M of rare earth metals.

[0016] The rare earth metal complex represented by the above formula (1) is produced by the following scheme.

[0017]

(Where A,

M, X, n, m, p and q are the same as above. )

That is, a sodium salt of an aromatic organic ligand represented by the formula (2) is reacted with a rare earth metal salt represented by the formula (3) in water to form a rare earth metal having an aromatic organic ligand. Complexes can be produced.

Considering practical availability, the aromatic organic ligand sodium salt is a sodium salt of 4-diphenylphosphinobenzoic acid (A is a benzene ring, R ¹ is —COO— group, and R ² is hydrogen Atom, R ³ is diphenylphosphino group), sodium salt of 4- (4-hydroxyphenyl) benzoic acid (A is benzene ring, R ¹ is —COO— group, R ² is hydrogen atom, R ³ is hydroxy And the like.

As the rare earth metal salt, M is La, Eu, Tb, or Yb, and X is a halogen ion (particularly CI—). Is preferably used because it is economically easy to obtain and has excellent reactivity in water.

The amount of the rare earth metal salt to be charged is determined according to the aromatic organic ligand sodium salt used, but is not limited as long as the rare earth metal complex is generated. Preferably, the charging amount is such that the value of m in equation (3) is 1Z3 with respect to the value of p in equation (2).

[0021] In this reaction, water is used as a reaction solvent. The amount used is not particularly limited, but under these conditions, which are preferably about 500 times the mass of the ligand, the product is almost quantitatively recovered as a white precipitate. In addition, since the by-product sodium halogenide is dissolved in water, separation of the target product and the by-product is easy.

The reaction temperature is preferably from 0 to 100 ° C, particularly preferably from 10 to 50 ° C.

The reaction time is not particularly limited, but the reaction is completed in a short time, and is usually completed within one hour.

Since the reaction product precipitates as described above, the precipitate is collected by filtration, washed sufficiently with water, and dried under reduced pressure to obtain the desired product as a milky white powder.

[0022] As a method for producing the sodium salt of the aromatic organic ligand represented by the above formula (2), for example, the carboxylic acid or phosphonic acid of the aromatic organic ligand is reacted with sodium carbonate under boiling conditions in water. Forces to be mentioned are not limited to this.

Example

Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited to the following Examples.

The analysis conditions and the like adopted in the examples are as follows.

[1] Elemental analysis

CHNS / O elemental analyzer: PE200 Series II (Perkin—Elmer)

[2] Infrared spectroscopy (IR)

IR device: SPECTRUM 2000 (Perkin-Elmer)

Measurement conditions: KBr tablet method

Measuring range: 4000 ~ 400cm- ¹

[3] Relative fluorescence quantum yield measurement The fluorescence quantum yield of the complex of the organic ligand sodium salt and various rare earth metals was determined by measuring the fluorescence spectrum at the following excitation wavelength using the following fluorescence spectrum measuring device, and calculating the relative fluorescence quantum yield from the fluorescence spectrum area ratio.

Fluorescence spectrometer: LS40B (Perkin-Elmer)

Excitation wavelength: 366nm

[Synthesis Example 1] 4 Synthesis of sodium diphenylphosphinobenzoate

[Formula 7]

[0025] About 120 ml of water was boiled and degassed. There 4-diphenylphosphinobenzoic acid (0.

2 g, 0.65 mmol) were added. Next, 5 ml of an aqueous solution of sodium carbonate (38. Img, 0.36 mmol) was slowly added dropwise, and when the solution became neutral with pH test paper, the addition was completed. After allowing to cool to room temperature, the precipitated white precipitate was removed by filtration, and the filtrate was concentrated and dried to obtain the desired product (yield 94%).

The structure of the target product was confirmed from the following analysis values.

IR (KBr, cm " ¹ ): 1690 (COOH, st) disappearance (carboxyl group disappearance of raw material, see IR chart of Fig. 1; Fig. 13 shows IR chart of 4 diphenylphosphinobenzoic acid of raw material) )

[Synthesis Example 2] Synthesis of lanthanum 4 diphenylphosphinobenzoate

[Formula 8]

4-Diphenylphosphinobenzoic acid sodium salt (0.2 g, 0.65 mmol) was dissolved in about 120 ml of water. Dissolve lanthanum chloride heptahydrate (0.0808 g, 0.22 mmol) in 5 ml of water. The solution was slowly added dropwise to an aqueous solution of 4-diphenylphosphinobenzoic acid-sodium. The obtained white precipitate was collected by filtration with a Kiriyama funnel, washed sufficiently with water, and dried to obtain the desired product (0.213 g, yield 88%).

IR (KBr, cm " ¹ ): 1690 (COOH, st) disappearance (see IR chart in Fig. 2)

Elemental analysis (wt%): C: 61.4, H: 3.6 [Theoretical value: 3 molecules of water per molecule of target compound, C: 61.7, H: 4.3]

[Synthesis Example 3] Synthesis of 4 diphenylphosphinobenzoic acid europium complex

[Formula 9]

[0029] 4-Diphenylphosphinobenzoic acid sodium salt (0.2 g, 0.65 mmol) was dissolved in about 120 ml of water. Pium chloride hexahydrate hexahydrate (0.0804 g, 0.22 mmol) was dissolved in 5 ml of water, and the solution was slowly dropped into aqueous solution of 4-diphenylphosphinobenzoic acid-sodium. The resulting white precipitate was collected by filtration with a Kiriyama funnel, washed sufficiently with water, and dried to obtain the desired product. (0.207g, 79% yield)

IR (KBr, cm " ¹ ): 1690 (COOH, st) disappearance (see IR chart in Fig. 3)

Elemental analysis (wt%): C: 60.5, H: 4.0 [Theoretical value: 2 molecules of target substance and 7 molecules of water, C: 60.5, H: 4.4]

[Synthesis Example 4] Synthesis of terbium complex of 4-difluorophosphinobenzoic acid

[0031] 4-Diphenylphosphinobenzoic acid sodium salt (0.2 g, 0.65 mmol) was dissolved in about 120 ml of water. Terbium chloride hexahydrate (0.0812 g, 0.22 mmol) was dissolved in 5 ml of water, and the solution was slowly dropped into aqueous solution of 4-diphenylphosphinobenzoic acid-sodium. The resulting white precipitate was collected by filtration with a Kiriyama funnel, washed sufficiently with water, and dried to obtain the desired product (0.186 g, yield 76%).

IR (KBr, cm " ¹ ): 1690 (COOH, st) disappearance (See Fig. 4: IR chart)

Elemental analysis (wt%): C: 62.0, H: 3.9 [Theoretical value: 1 molecule of the target compound as 2 molecules of water, C: 61.6, H: 4.2]

[Synthesis Example 5] 4 Synthesis of ytterbium complex of diphenylphosphinobenzoate

[Formula 11]

[0033] Sodium 4-diphenylphosphinobenzoate (0.2 g, 0.65 mmol) was dissolved in about 120 ml of water. Ytterbium chloride hexahydrate (0.0846 g, 0.22 mmol) was dissolved in 5 ml of water, which was slowly dropped into an aqueous solution of sodium 4-diphenylphosphinobenzoate. The obtained white precipitate was collected by filtration with a Kiriyama funnel, washed sufficiently with water, and dried to obtain the desired product (0.166 g, yield 68%).

IR (KBr, cm " ¹ ): 1690 (COOH, st) disappearance (See Fig. 5: IR chart)

Elemental analysis (wt%): C: 61.8, H: 3.9 [Theoretical value: One molecule of the target compound as one molecule of water, C: 61.8, H: 4.0]

[Synthesis Example 6] Synthesis of 4 yttrium complex of diphenylphosphinobenzoate

[0035] 4-Diphenylphosphinobenzoic acid sodium salt (0.2 g, 0.65 mmol) was dissolved in about 120 ml of water. Yttrium chloride hexahydrate (0.0662 g, 0.22 mmol) was dissolved in 5 ml of water, which was slowly dropped into an aqueous solution of 4-diphenylphosphinobenzoic acid-sodium. The resulting white precipitate was collected by filtration with a Kiriyama funnel, washed sufficiently with water, and dried to obtain the desired product (0.185 g, yield 81%).

IR (KBr, cm " ¹ ): 1690 (COOH, st) disappearance (see Fig. 6: IR chart)

Elemental analysis (wt%): C: 66.1, H: 4.3 [Theoretical value: 1 molecule of the target substance, 2 molecules of water, C: 65.8, H: 4.4]

[Synthesis Example 7] Synthesis of 4- (4-hydroxyphenyl) benzoic acid sodium salt

[Formula 13]

[0037] About 120 ml of water was boiled and degassed. There is 4- (4-hydroxyphenyl) benzoic acid

(0.2 g, 0.93 mmol) was added. Next, 5 ml of an aqueous solution of sodium carbonate (54.4 mg, 0.51 mmol) was slowly added dropwise, and when the solution became neutral with pH test paper, the addition was completed. After allowing to cool to room temperature, the precipitated white precipitate was removed by filtration, and the filtrate was concentrated and dried to obtain the desired product (yield: 91%).

IR (KBr, cm " ¹ ): 1690 (COOH, st) disappearance (carboxyl group disappearance of raw material, refer to IR chart in FIG. 7). In addition, FIG. 14 shows IR of raw material 41- (4-hydroxyphenyl) benzoic acid. The chart was shown.) Example 1 Synthesis of Lanthanum 4- (4-hydroxyphenyl) benzoate Complex

[0039] 4 (4-Hydroxyphenyl) benzoic acid sodium salt (0.2 g, 0.93 mmol) was dissolved in about 120 ml of water. Lanthanum chloride heptahydrate (0.151 g, 0.31 mmol) was dissolved in 5 ml of water, and it was slowly added dropwise to an aqueous solution of sodium 4- (4-hydroxyphenyl) benzoate. The resulting white precipitate was collected by filtration with a Kiriyama funnel, washed sufficiently with water, and dried to obtain the desired product (0.228 g, yield 89%).

IR (KBr, cm " ¹ ): disappearance of 1690 (COOH, st) (See Fig. 8: IR chart)

Elemental analysis (wt%): C: 55.7, H: 3.8 [Theoretical value: 3 molecules of water per molecule of target compound, C: 56.3, H: 4.0]

Example 2 Synthesis of 4- (4-hydroxyphenyl) benzoic acid europium pium complex

[Formula 15]

4 About 120 ml of water was dissolved in sodium 4- (4-hydroxyphenyl) benzoate (0.2 g, 0.93 mmol). Pium chloride hexahydrate hexahydrate (0.1136 g, 0.31 mmol) was dissolved in 5 ml of water, and the solution was slowly added dropwise to an aqueous solution of sodium 4- (4-hydroxyphenyl) benzoate. The resulting white precipitate was collected by filtration with a Kiriyama funnel, washed sufficiently with water, and dried to obtain the desired product (0.223 g, yield: 85%).

The structure of the target product was confirmed from the following analysis values. IR (KBr, cm): 1690 (COOH, st) disappearance (see Fig. 9: IR chart) Elemental analysis (wt%): C: 56.5, H: 3.6 [Theoretical value: 3 molecules of water per molecule of target compound As

C: 55.4, H: 3.9]

Example 3 Synthesis of Terbium Complex of 4- (4-Hydroxyphenyl) benzoic Acid

[Formula 16]

4 (4-Hydroxyphenyl) benzoic acid sodium salt (0.2 g, 0.93 mmol) was dissolved in about 120 ml of water. Terbium chloride hexahydrate (0.1157 g, 0.31 mmol) was dissolved in 5 ml of water, and the solution was slowly added dropwise to an aqueous solution of sodium 4- (4-hydroxyphenyl) benzoate. The resulting white precipitate was collected by filtration with a Kiriyama funnel, washed sufficiently with water, and dried to obtain the desired product (0.165 g, yield 63%).

IR (KBr, cm " ¹ ): 1690 (COOH, st) disappearance (See Fig. 10: IR chart)

Elemental analysis (wt%): C: 55.4, H: 3.7 [Theoretical value: 3 molecules of water per molecule of target compound, C: 54.9, H: 3.9]

Example 4 Synthesis of Mono-Ytterbium Complex of 4- (4-Hydroxyphenyl) benzoic Acid

[Formula 17]

4 (4-Hydroxyphenyl) benzoic acid sodium salt (0.2 g, 0.93 mmol) was dissolved in about 120 ml of water. Dissolve ytterbium chloride hexahydrate (0.1201 g, 0.31 mmol) in 5 ml of water and add it to aqueous sodium 4- (4-hydroxyphenyl) benzoate solution. Made and dropped. The obtained white precipitate was collected by filtration with a Kiriyama funnel, washed sufficiently with water, and dried to obtain the desired product (0.244 g, yield 89%).

IR (KBr, cm " ¹ ): 1690 (COOH, st) disappearance (See Fig. 11: IR chart)

Elemental analysis (wt%): C: 52.9, H: 3.6 [Theoretical value: 1 molecule of the target substance, 4 molecules of water, C: 52.9, H: 4.0]

Example 5 Synthesis of Yttrium Complex of 4- (4-Hydroxyphenyl) benzoic Acid

[Formula 18]

[0047] 4 (4-Hydroxyphenyl) benzoic acid sodium salt (0.2 g, 0.93 mmol) was dissolved in about 120 ml of water. Yttrium chloride hexahydrate (0.0940 g, 0.31 mmol) was dissolved in 5 ml of water, and the solution was slowly added dropwise to an aqueous solution of sodium 4- (4-hydroxyphenyl) benzoate. The resulting white precipitate was collected by filtration with a Kiriyama funnel, washed sufficiently with water, and dried to obtain the desired product (0.194 g, yield: 84%).

IR (KBr, cm " ¹ ): 1690 (COOH, st) disappearance (See Fig. 12: IR chart)

Elemental analysis (wt%): C: 62.8, H: 4.1 [theoretical value: one molecule of the target compound as one molecule of water, C: 62.7, H: 3.9]

Example 6 Measurement of Relative Fluorescence Quantum Yield of Metal Complex of 4-Diphenylphosphinobenzoic Acid

Relative fluorescence quantum yield measurements were performed for each of the metals lanthanum, europium and terbium. As a comparison, Alq (formula (4)), which is a typical low molecular light emitting material, was also measured. Table 1 shows the results

Three

Shown in

[0049]

[0050] [Table 1]

Relative fluorescence quantum yield measurement of metal complexes of 4-diunylphosphinobenzoic acid

[0051] Table: U As shown [ko, lantern: 0.673, yu π picum: 0.651, Tenorevi, Kumu: 0.518, all of which exceeded Alq: 0.503 _c

Claims

Claims [1] A rare earth metal complex represented by the formula (1).

[Formula 1]-, M ³⁺ ) _M (1)

ⁿ

(Wherein, M represents La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc, or Y,

A represents a benzene ring, a naphthalene ring, an anthracene ring, a pyridine ring, a thiene phen ring, a furan ring, a pyrazole ring, or an imidazole ring;

R ¹ represents a COO— group, CONH—CH (R ⁴ ) (R ⁴ represents an alkyl group having 1 to 10 carbon atoms), or —COO— group,

R ² and R ³ are each independently a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and an alkoxycarbol having 1 to 10 carbon atoms. Group, nitro group, amino group, hydroxyl group, COO— group, phenyl group optionally substituted with Z, naphthyl group optionally substituted with Z, biphenyl group optionally substituted with Z And Z may be substituted with an anthryl group, a diheteroarylphosphino group, a dialkylphosphino group having 1 to 10 carbon atoms, an alkylarylphosphino group having 1 to 10 carbon atoms, or a carbon atom having 1 to 10 carbon atoms. Wherein the aryl group is a phenyl group which may be substituted by Z, a naphthyl group which may be substituted by Z, and a group which is substituted by Z! , May be substituted with a biphenyl group or Z! Represents Ntoriru group, heteroaryl group wherein represents optionally substituted furyl group optionally, Z in an optionally substituted Vila Zoriru group or an imidazolyl group optionally substituted by Z in Z.),

Z is a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a carbon atom having 1 to: L0 alkoxycarbol group, nitro group, amino group, hydroxyl group, COO — Represents a group or a phenyl group,

n and m represent an integer of 1 or more. ]

[2] Equation (2) [Chemical 2]

[In the formula, A represents a benzene ring, a naphthalene ring, an anthracene ring, a pyridine ring, a thiophene ring, a furan ring, a pyrazole ring, or an imidazole ring;

n and p represent an integer of 1 or more. ]

And an organic ligand sodium salt represented by the formula (3)

[Formula 3]

(Where M is La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, L u, Sc, or Y,

X represents halogen ion, nitrate ion, sulfate ion, perchlorate ion, boron tetrafluoride ion, acetate ion,

m and q represent an integer of 1 or more. )

Reacting a rare earth metal salt represented by the formula with water in formula (1)

[Formula 4]

(Where A,

R ² , R ³ , M, n and m are the same as above. )

A method for producing a rare earth metal complex represented by the formula:

A light emitting material comprising a rare earth metal complex represented by the formula (1).

[Formula 5]

R ¹ represents a —COO— group, —CONH—CH (R ⁴ ) (R ⁴ represents an alkyl group having 1 to 10 carbon atoms), or —COO— group,

R ² and R ³ are each independently a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and an alkoxycarbol having 1 to 10 carbon atoms. Group, nitro group, amino group, hydroxyl group, —COO— group, phenyl group optionally substituted with Z, naphthyl group optionally substituted with Z, biphenyl optionally substituted with Z Group, anthryl group optionally substituted by Z, diarylphosphino group, diheteroarylphosphino group, dialkylphosphino group having 1 to 10 carbon atoms, alkylarylphosphino group having 1 to 10 carbon atoms Represents an alkyl heteroarylphosphino group having 1 to 10 carbon atoms (wherein The aryl group is a phenyl group which may be substituted with Z, a naphthyl group which may be substituted with Z, or may be substituted with Z !, or may be substituted with a biphenyl group or Z. Wherein the heteroaryl group is a furyl group which may be substituted by Z, a furyl group which may be substituted by Z, or a benzoryl group or Z which is substituted by Z. Represents an imidazolyl group. ),

Z is a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and a carbon number of 1 to: LO alkoxycarboxy group, nitro group, amino group, hydroxyl group, COO — Represents a group or a phenyl group,

n and m represent an integer of 1 or more. ]