JP2014152120A - Organometallic complex - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organometallic complex which can emit blue to violet fluorescence etc. with high color purity, and can be used suitably, e.g., as a luminescent material utilizing fluorescence.SOLUTION: The organometallic complex is represented by the general formula (1). (In the formula, a central metal atom M represents a metal atom belonging to one of groups 1 to 3, 12 and 13 in the periodic table; an arrow from a nitrogen atom to the central metal atom M means that the nitrogen atom is coordinated to the central metal atom M; and n is 2 or 3.)

Description

The present invention relates to an organometallic complex. More specifically, the present invention relates to an organometallic complex that can be suitably used as a light-emitting material utilizing fluorescence.

An organometallic complex has attracted attention as a light emitting material utilizing fluorescence, for example. In recent years, light emitting materials using fluorescence have a wide range of uses such as dye lasers, fluorescent pigments, fluorescent dyes, fluorescent marking materials, fluorescent indicators, security inks, and sensors, and the demand for these materials is expanding.

As a conventional organometallic complex, the use of a specific structure having a heteroatom-containing ring as a ligand and the use of a specific metal as a central metal atom is disclosed (for example, Patent Documents 1 to 9, Non-Patent Documents (See Patent Documents 1 to 3.)

International Publication No. 02/078343 JP 2000-252067 A JP 2000-302754 A Japanese Patent Application Laid-Open No. 11-144872 JP 2001-271063 A JP 2001-40346 A JP 2004-210779 A JP 2005-53912 A JP 2007-227951 A

“Soviet Journal of Coordination Chemistry”, 1990, No. 16, p. 876-880 “Comptes Rendus Chimie”, 2007, Vol. 10, p. 109-115 “Inorganica Chimica Acta”, 1986, Vol. 113, p. 1-7

The organometallic complex is composed of a ligand and a central metal atom, and by selecting each of them, an electron orbit or the like can be designed according to the purpose, and its function can be suitably expressed. As described above, in recent years, organic metal complexes are expected to be used in a wide range of applications such as dye lasers, fluorescent pigments, fluorescent dyes, fluorescent marking materials, fluorescent indicators, security inks, and sensors as light emitting materials that utilize fluorescence. Yes. Increasing variations of organometallic complexes that are suitably used for such applications can broaden the scope of selection when the organometallic complexes are used for various purposes in the applications, and have great technical significance. is there.

Many organic compounds and metal complexes have been studied as luminescent materials, but it is difficult to achieve sufficient color purity and material stability, especially for those emitting blue to violet fluorescence. There are few, and further development is desired.

The present invention has been made in view of the above-mentioned present situation, and is capable of emitting particularly blue to purple fluorescence with high color purity while ensuring sufficient stability as a complex. It is an object to provide an organometallic complex that can be suitably used as a material or the like.

The inventors of the present invention have studied various compounds that can be suitably used as a light emitting material utilizing fluorescence, and have focused on organometallic complexes. In particular, attention was paid to organometallic complexes using chelate ligands having a structure in which a ring having a nitrogen atom as a ring constituent atom is bonded to a carbon atom adjacent to a carbon atom directly bonded to an oxygen atom in a phenol ring. Many of such organometallic complexes have the property of emitting fluorescence. Then, the type of the central metal atom is specified, and in the chelate ligand, the position of the nitrogen atom in the ring having a nitrogen atom is specified, or the substituents of the ring having a nitrogen atom are combined to form a ring structure. The band gap between the highest occupied orbital (HOMO) and the lowest unoccupied orbital (LUMO) can be expanded sufficiently by further specifying the structure of the ring having a nitrogen atom, etc. As a fluorescent light-emitting material, etc., it has been found that the color purity of light emission can be improved and the stability of the complex can be sufficiently improved, and the above problem can be solved brilliantly. In addition, the present inventors have found that hydrogen atoms bonded to such a ligand skeleton can be substituted with other atoms or atomic groups, thereby producing organometallic compounds having various structures. It has been reached.

That is, the present invention is an organometallic complex represented by the following general formula (1).

(In the formula, the central metal atom M represents a metal atom belonging to Group 1 to Group 3, Group 12 or Group 13 of the periodic table. The arrow from the nitrogen atom to the central metal atom M represents nitrogen. .n indicating that atoms are coordinated to the central metal atom M is 2 or 3 .R ¹ to R ³ are the same or different, represent a hydrogen atom or a monovalent substituent .R ⁴ ˜R ⁷ are the same or different and each represents a hydrogen atom or a monovalent or divalent substituent, and any two of R ^{4 to} R ⁷ represent a divalent substituent, which are bonded to each other to form an aromatic A ring structure other than a ring may be formed.)
The present invention is described in detail below.

In the present specification, coordinating means that the nitrogen atom acts on the central metal atom M in the same manner as the ligand and has a chemical influence.

The central metal atom M in the organometallic complex of the present invention preferably represents beryllium, magnesium, calcium, barium, scandium, zinc, aluminum or gallium. More preferably, the central metal atom M represents beryllium, magnesium, zinc, or aluminum. More preferably, the central metal atom M represents magnesium or zinc.

In the general formula (1) in the organometallic complex of the present invention, R ^{1 to} R ⁷ are the same or different and are a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or a halogen having 1 to 12 carbon atoms. Hydrocarbon group, C 0-12 heteroatom-containing ring group, cyano group, C 1-12 alkoxy group, C 6-12 aryloxy group, C 1-12 alkylamino group, or And preferably an arylamino group having 6 to 18 carbon atoms. Even if these monovalent substituents are replaced with hydrogen atoms, they do not particularly contribute to material deterioration or performance deterioration. In addition, the hetero atom-containing ring group means a cyclic group containing a hetero atom which is an atom other than carbon and hydrogen as a ring constituent atom.

It is preferable that at least two of the above R ^{4 to} R ⁷ in the organometallic complex of the present invention represent a hydrogen atom. More preferably, at least three of R ^{4 to} R ⁷ represent a hydrogen atom. For example, R ⁵ and R ⁶ are the same or different and each represents a monovalent substituent, R ⁴ and R ⁷ each represent a hydrogen atom, R ⁵ represents a monovalent substituent, R ⁴ , R 6 Preferred are those in which ⁶ and R ⁷ each represent a hydrogen atom, the above R ⁶ represents a monovalent substituent, and R ⁴ , R ⁵ and R ⁷ each represent a hydrogen atom. Particularly preferably, R ^{4 to} R ⁷ each represent a hydrogen atom.

The halogen atom is preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.
The hydrocarbon group having 1 to 20 carbon atoms is a straight chain having 1 to 12 carbon atoms such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, hexyl group, and octyl group. C2-C12 alkenyl groups such as vinyl, 1-propenyl, allyl, and styryl groups; C2-C12 such as ethynyl, 1-propynyl, and propargyl groups An alkynyl group; a cyclic alkyl group having 5 to 12 carbon atoms such as a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group; an aryl group having 6 to 20 carbon atoms that may be substituted with an alkyl group, an alkenyl group, an alkynyl group, or the like It is done.

The hydrocarbon group having 1 to 20 carbon atoms is preferably 1 to 8 carbon atoms among those described above. More preferably, it is 1-6. More preferably, it is 1-4. Particularly preferred is 1.

The halogenated hydrocarbon group having 1 to 12 carbon atoms is a haloalkyl group having 1 to 12 carbon atoms such as a fluoromethyl group, a difluoromethyl group or a trifluoromethyl group; an aryl having 6 to 12 carbon atoms substituted with a halogen atom Groups.
The halogenated hydrocarbon group having 1 to 12 carbon atoms is preferably 1 to 8 carbon atoms among those described above. More preferably, it is 1-6.

The hetero atom-containing cyclic group having 0 to 12 carbon atoms is a 5-membered nitrogen-containing cyclic group such as pentazole; triazole, tetrazole, imidazole, oxazole, isoxazole, thiazole, isothiazole, pyrazole, pyrrole, pyrrolidine, oxazoline, furan Preferred examples include 5-membered ring heterocyclic groups such as thiophene; and 6-membered heterocyclic groups such as pyridine, pyrazine, piperidine, morpholine, thiazine and the like. These heteroatom-containing ring groups may be substituted with a halogen atom, an alkyl group, an alkoxy group, an alkenyl group, or an alkynyl group. The C 0-12 heteroatom-containing ring group is preferably composed of one ring structure, in other words, it does not constitute a plurality of ring structures.
The C 0-12 heteroatom-containing cyclic group preferably has 1-8 carbon atoms among those described above. More preferably, it is 1-6.

The alkoxy group having 1 to 12 carbon atoms is methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, isobutoxy group, tert-butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group A straight chain or branched chain such as is preferable.
It is preferable that the said C1-C12 alkoxy group is C1-C8 among what was mentioned above. More preferably, it is 1-6. More preferably, it is 1-3.

Examples of the aryloxy group having 6 to 12 carbon atoms include a phenyloxy group and a benzyloxy group. In the aryloxy group having 6 to 12 carbon atoms, for example, the aryl group portion of the aryloxy group may be substituted with a halogen atom, an alkyl group, an alkoxy group, an alkenyl group, an alkynyl group, or the like.
Among the above-mentioned aryloxy groups having 6 to 12 carbon atoms, those having 6 to 10 carbon atoms are preferable. More preferably, it is 6-8. More preferably, it is 6.

Examples of the alkylamino group having 1 to 12 carbon atoms include monoalkylamino groups having 1 to 12 carbon atoms such as a methylamino group and an ethylamino group; and 2 carbon atoms such as a dimethylamino group, a diethylamino group, a pyrrolidinyl group, and a morpholinyl group. -12 acyclic or cyclic dialkylamino groups are preferred.
It is preferable that the said C1-C12 alkylamino group is C1-C8 among what was mentioned above. More preferably, it is 1-6. More preferably, it is 1-4.

Examples of the arylamino group having 6 to 18 carbon atoms include monoarylamino groups having 6 to 18 carbon atoms such as phenylamino group and benzylamino group; N-alkyl-N— such as N-methyl-N-phenylamino group. Preferred examples include arylamino groups; acyclic or cyclic diarylamino groups having 12 to 18 carbon atoms such as diphenylamino group, carbazolyl group, phenoxazinyl group, and phenothiazinyl group. The acyclic diarylamino group means a group having no ring structure other than an aromatic ring, and the cyclic diarylamino group means a group having a ring structure other than an aromatic ring. In the arylamino group having 6 to 18 carbon atoms, for example, the aryl group portion of the arylamino group may be substituted with a halogen atom, an alkyl group, an alkoxy group, an alkenyl group, an alkynyl group, or the like.
Of the above-mentioned arylamino groups having 6 to 18 carbon atoms, those having 8 to 18 carbon atoms are preferable. More preferably, it is 12-18. More preferably, it is 12.

In addition, the monovalent substituent is an acyl group such as an acetyl group, a propionyl group or a butyryl group; an N, N-dialkylcarbamoyl group such as an N, N-dimethylcarbamoyl group or an N, N-diethylcarbamoyl group; a thioacetyl group Thiocarbonyl groups such as thiobenzoyl group and methoxythiocarbonyl group; dioxaborolanyl group, stannyl group, silyl group, ester group, formyl group, thioether group, epoxy group, isocyanate group, hydroxyl group, sulfo group, sulfonyl It may be a group, phosphoryl group, carboxyl group or the like.

The monovalent substituent may be substituted with a halogen atom, a hetero atom, an alkyl group, an alkoxy group, an alkenyl group, an alkynyl group, an aromatic ring, or the like as long as the effects of the present invention can be exhibited. In addition, when the alkyl group, aryl group, heteroatom-containing ring group or the like is substituted and has a monovalent substituent (when the monovalent substituent further has a monovalent substituent), monovalent substitution There are no particular restrictions on the position or number of groups to which the group is bonded.

Among these, the monovalent substituent is preferably a hydrocarbon group having 1 to 12 carbon atoms or a halogenated hydrocarbon group having 1 to 12 carbon atoms. The hydrocarbon group having 1 to 12 carbon atoms is more preferably the linear or branched alkyl group having 1 to 12 carbon atoms or the aryl group having 6 to 12 carbon atoms. The halogenated hydrocarbon group having 1 to 12 carbon atoms is more preferably the fluorinated hydrocarbon group having 1 to 12 carbon atoms. More preferably, it is a trifluoromethyl group.

In the organometallic complex represented by the general formula (1), any two of R ^{4 to} R ⁷ represent a divalent substituent, and these are bonded to each other to form a ring structure other than an aromatic ring. It may be formed. That is, any two of R ^{4 to} R ⁷ are bonded to each other by a covalent bond and a divalent substituent that is also bonded to the carbon atom constituting the phenol ring shown in the general formula (1). It may represent. At this time, the two divalent substituents together with the carbon atom of the phenol ring to which the two divalent substituents are bonded form a ring structure other than the aromatic ring. Any ring structure other than the aromatic ring may be used as long as it does not have multiple bonds constituting a conjugated system with the phenol ring. With such a configuration, the organometallic complex of the present invention can emit blue fluorescence or the like with high color purity. Moreover, it is preferable that ring structures other than this aromatic ring are comprised only from a carbon atom. In other words, the ring structure other than the aromatic ring is preferably not a heteroatom-containing ring structure.

The ring structure other than the aromatic ring is preferably a 5- to 7-membered ring, for example. More preferably, it is a 6-membered ring. The atoms constituting the ring structure other than the aromatic ring are the same or different and have a hydrogen atom or a monovalent substituent. When the atoms constituting the ring structure other than the aromatic ring have a monovalent substituent, the preferred configuration of the monovalent substituent is the same as the preferred configuration of the monovalent substituent described above. Moreover, it is especially preferable that each atom constituting the ring structure other than the aromatic ring has a hydrogen atom.

The divalent substituent preferably corresponds to, for example, the above-described monovalent substituent having a hydrogen atom. That is, a structure in which one hydrogen atom is eliminated from one having a hydrogen atom as the monovalent substituent can be used. Such substituents also do not particularly contribute to material deterioration or performance deterioration.

In addition, that the substituents in R ^{1 to} R ³ are monovalent substituents means that these substituents are not bonded to each other and do not form a condensed ring structure. Moreover, these substituents and the substituent of R < ⁴ > -R < ⁷ > are not couple | bonded, and it means that the condensed ring structure is not formed. Furthermore, the organometallic complex represented by the general formula (1) is usually not bonded to another organometallic complex by a covalent bond via a substituent or the like. With such a configuration, the organometallic complex of the present invention can emit blue fluorescence or the like with high color purity.

Although the monovalent substituent and the divalent substituent in the organometallic complex of the present invention have been described in detail, the above R ^{1 to} R ³ may be the same or different, and may be a hydrogen atom or a straight chain having 1 to 4 carbon atoms. Representing a chain or branched alkyl group is one preferred form of the invention. More preferably, for example, R ^{1 to} R ³ each represent a hydrogen atom, or at least one of R ^{1 to} R ³ represents a methyl group, and the other represents a hydrogen atom. More preferably, for example, R ^{1 to} R ³ each represent a hydrogen atom.

In another preferred embodiment of the present invention, at least one of R ^{1 to} R ³ is an aryl group having 6 to 12 carbon atoms. More preferably, at least one of R ^{1 to} R ³ is a phenyl group or a naphthyl group. As in the case where at least one of R ^{1 to} R ³ is a phenyl group or a naphthyl group, the effect of the present invention can be exhibited by directly bonding the aromatic ring to the heterocycle of the metal complex of the present invention, The heat resistance can be remarkably improved.

In the general formula (1), n is 2 or 3, and the number is usually determined by the valence of the metal atom. In other words, there are two or three ligands of the organometallic complex represented by the general formula (1). These may be the same or different, but are preferably the same. Further, n is preferably 2.

The organometallic complex of the present invention can be synthesized by various commonly used techniques. The ligand according to the organometallic complex of the present invention can be produced, for example, via a compound in which the oxygen atom of the phenol ring of the ligand is alkoxylated (hereinafter also referred to as an alkoxy form).
The above alkoxy compound is, for example, an organic solvent such as a 5-membered aromatic compound having a nitrogen atom as a ring constituent atom and a phenol in which hydrogen on the ortho-position carbon is substituted with a reactive group such as a halogen atom. It can be obtained by reacting in the presence of a catalyst in a solvent. Moreover, in the alkoxybenzene which has a substituent on the carbon of ortho position, it can also obtain by cyclizing a part of this substituent.

The ligand according to the organometallic complex of the present invention can be obtained by dealkylating an alkoxy group using various reaction reagents in the above alkoxy body. Moreover, in the phenol which has a substituent on the carbon of ortho position, it can also obtain by cyclizing a part of this substituent.
The organometallic complex of the present invention can be obtained by reacting the above ligand with a metal salt under neutral or basic conditions. However, the manufacturing method of the organometallic complex of this invention is not restrict | limited to this.

The organometallic complex of the present invention can be suitably used as, for example, a light emitting material utilizing fluorescence. As a light emitting material using fluorescence, a dye laser, a fluorescent pigment, a fluorescent dye, a fluorescent marking material, a fluorescent indicator, a security ink, a sensor, and the like are particularly preferable.

When used suitably as a light emitting material that emits blue to purple light, the fluorescence emission wavelength is preferably in the range of 360 to 480 nm in fluorescence spectroscopic analysis. The difference (band gap) between the energy level of the highest occupied orbital (HOMO) of the organometallic complex of the present invention and the energy level of the lowest unoccupied orbital (LUMO) of the organometallic complex of the present invention is 2. It is preferable that it is 6 eV or more. More preferably, it is 2.8 eV or more. The difference is preferably 4.0 eV or less.
The difference between the energy levels of HOMO and LUMO of the organometallic complex of the present invention can be evaluated by a method of measuring by ultraviolet-visible spectroscopy (UV-Vis).

The organometallic complex of the present invention is excellent in stability as a complex, and can emit, for example, blue fluorescence with high color purity, such as dye laser, fluorescent pigment, fluorescent dye, fluorescent marking material, fluorescent indicator, security It can be suitably used as a light emitting material utilizing fluorescence, such as ink and sensor.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Note that “%” means “mass%” unless otherwise specified. Further, in the present specification, “substitution” and “substituent” refer to substitution with an atom or atomic group other than a hydrogen atom, and a group having such substitution, respectively. Further, the “phenol ring” includes a phenol group in which a hydrogen atom is eliminated from its hydroxyl group.

Note that fluorescence is light emission from an excited singlet state. In general, when light or electric energy is applied to a substance, the electronic state changes from a state called a ground state to an excited state (this process is called excitation). There are two types of excited states, a singlet excited state and a triplet excited state. When light energy is applied to the organometallic compound of the present invention at room temperature, it is normally excited to a 100% singlet excited state. In the above-described uses of the present invention, it is considered that most of the uses utilize light emission obtained by adding light energy.

Various measurements on the compounds synthesized in the examples were performed as follows.
⁽¹ H-NMR measurement)
The sample was dissolved in deuterated chloroform or deuterated dimethyl sulfoxide containing tetramethylsilane and measured with a nuclear magnetic resonance apparatus (Gemini 2000, 400 MHz, manufactured by Varian).
(Fluorescence spectrum measurement)
The sample was used as a dilute solution of dimethylformamide, and the fluorescence spectrum was measured using a fluorescence spectrophotometer (F-7000, manufactured by Hitachi High-Technologies Corporation). The excitation wavelength was 350 nm, and the place where the emission intensity was maximum was the fluorescence wavelength (λmax).

Example 1 2- (1H-pyrazol-1-yl) phenolato zinc (II)
1- (2-methoxyphenyl) -1H-pyrazole

Pyrazole (4.68 g, 40 mmol), 2-iodoanisole (2.6 ml, 20 mmol), copper (I) oxide (290 mg, 2.0 mmol), cesium carbonate (7.82 g, 24 mmol) in dehydrated DMF (20 ml). It melt | dissolved and it was made to react at 100 degreeC for 24 hours. After the reaction, the solid content was removed by Celite filtration. The filtrate was dissolved in ethyl acetate (300 ml), washed with water and brine, the organic layer was collected and dried over sodium sulfate. Sodium sulfate was removed by filtration, the filtrate was concentrated, and the residue was purified by silica gel column chromatography (hexane: ethyl acetate = 1: 1) to obtain 3.48 g (yield 100%) of the desired product.
¹ H-NMR (400 MHz, CDCl ₃ ): δ 3.87 (s, 3H), 6.41 (s, 1H), 7.05 (t, 2H), 7.24-7.30 (m, 1H) , 7.70 (d, 1H), 8.01 (s, 1H)

2- (1H-pyrazol-1-yl) phenol

1- (2-methoxyphenyl) -1H-pyrazole (3.48 g, 20 mmol) was dissolved in dehydrated dichloromethane (40 ml) and cooled in a dry ice-acetone bath at −78 ° C. Boron tribromide (1.0 M dichloromethane solution, 40 ml, 40 mmol) was gently added dropwise thereto. Thereafter, the temperature was raised to room temperature and reacted for 24 hours. After the reaction, the reaction solution was ice-cooled and quenched by adding water. Dissolved in chloroform (200 ml) and washed with water, the organic layer was recovered and dried over sodium sulfate. Sodium sulfate was removed by filtration, the filtrate was concentrated, and the residue was purified by silica gel column chromatography (hexane: ethyl acetate = 1: 1) to obtain 2.3 g (yield 72%) of the desired product.
¹ H-NMR (400 MHz, CDCl ₃ ): δ 6.49 (s, 1H), 6.90 (t, 1H), 7.09 (d, 1H), 7.15 (t, 1H), 7.36 (D, 1H), 7.72 (s, 1H), 8.00 (d, 1H), 11.39 (br, 1H)

2- (1H-pyrazol-1-yl) phenolato zinc (II)

2- (1H-pyrazol-1-yl) phenol (1.0 g, 6.2 mmol) and zinc (II) chloride (430 mg, 3.1 mmol) were dissolved in methanol (15 ml) and stirred at room temperature for 10 minutes. Triethylamine (0.9 ml, 6.2 mmol) was added thereto and reacted for 24 hours. After the reaction, the precipitated solid was collected by filtration under reduced pressure and washed with methanol to obtain 800 mg (yield 75%) of the desired product.
¹ H-NMR (400 MHz, DMSO-d ₆ ): δ 6.44 (t, 2H), 6.55 (br, 2H), 6.85 (d, 2H), 6.99 (t, 2H), 7 .25 (d, 2H), 7.91 (br, 2H), 8.36 (s, 2H)

Example 2 2- (1H-pyrazol-1-yl) phenolatomagnesium (II)

2- (1H-pyrazol-1-yl) phenol (320 mg, 2.0 mmol) and magnesium (II) chloride hexahydrate (100 mg, 1.0 mmol) are dissolved in methanol (5 ml) and stirred at room temperature for 10 minutes. did. Triethylamine (0.56 ml, 4.0 mmol) was added thereto and reacted for 24 hours. After the reaction, the precipitated solid was collected by filtration under reduced pressure and washed with methanol to obtain 300 mg (yield 68%) of the desired product.
¹ H-NMR (400 MHz, DMSO-d ₆ ): δ 6.26 (br, 4H), 6.63 (br, 2H), 6.88 (br, 2H), 7.18 (br, 2H), 7 .39 (d, 2H), 8.18 (br, 2H)

From the measurement results of the fluorescence spectrum (measurement of the fluorescence emission wavelength), it was found that both of the organometallic complexes of Examples 1 and 2 can suitably emit blue to purple fluorescence.

From these measurement results, it was confirmed that the organometallic complexes of the examples are organometallic complexes that can be suitably used as a light-emitting material utilizing fluorescence. The organometallic complex of the present invention has the same structural characteristics as the organometallic complexes described in the examples, and has the same characteristics as the organometallic complexes described in the examples, and a light emitting material utilizing fluorescence Etc. can be suitably used.

Claims (3)

An organometallic complex represented by the following general formula (1):

(In the formula, the central metal atom M represents a metal atom belonging to Group 1 to Group 3, Group 12 or Group 13 of the periodic table. The arrow from the nitrogen atom to the central metal atom M represents nitrogen. .n indicating that atoms are coordinated to the central metal atom M is 2 or 3 .R ¹ to R ³ are the same or different, represent a hydrogen atom or a monovalent substituent .R ⁴ ˜R ⁷ are the same or different and each represents a hydrogen atom or a monovalent or divalent substituent, and any two of R ^{4 to} R ⁷ represent a divalent substituent, which are bonded to each other to form an aromatic A ring structure other than a ring may be formed.) The organometallic complex according to claim 1, wherein the central metal atom M represents beryllium, magnesium, zinc, or aluminum. In the general formula (1), R ^{1 to} R ⁷ are the same or different and are a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a halogenated hydrocarbon group having 1 to 12 carbon atoms, or a carbon number. A heteroatom-containing cyclic group having 0 to 12 carbon atoms, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an alkylamino group having 1 to 12 carbon atoms, or a 6 to 18 carbon atom The organometallic complex according to claim 1 or 2, which is an arylamino group.