JP2006016577A - Organic electroluminescent material and light-emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electroluminescent material and a light-emitting device, capable of changing luminescent color by a very simple means without doping any fluorescent dye and/or making multilayer luminescent layer, especially capable of easily attaining white luminescence. <P>SOLUTION: The organic electroluminescent material is such that a coordinated compound obtained by coordinating metallic ion species is used as a crosslinked ligand where ligands are linked to both sides of a conjugated oligomer having fluorescence-emitting core. In this material, the crosslinked ligand has preferably a structure of L<SB>1</SB>-B<SB>1</SB>-A-B<SB>2</SB>-L<SB>2</SB>(wherein, L<SB>1</SB>and L<SB>2</SB>are each a ligand selected from the group consisting of Formula (1); A is a fluorene core with fluorescent color development of Formula (2); and B<SB>1</SB>and B<SB>2</SB>are each an oligomer selected from the group in Formula (3)) and the metallic ion species is selected from zinc, aluminum, ruthenium, osmium, terbium, europium, platinum, gold and iridium. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention generally relates to an organic electroluminescent material suitable for use in an electronic device, and more particularly to a technique for changing a luminescent color in a conjugated oligomer organic electroluminescent material. The present invention also relates to a light emitting device using such an organic electroluminescent material.

  Organic electroluminescence (EL) elements are regarded as promising materials for next-generation flat panel display devices, and a large number of materials have been developed as organic electroluminescence materials therefor. Among them, the conjugated oligomer material is a particularly important substance because the fluorescent color of the oligomer can be changed depending on the structure, and oligomers having red, blue, and yellow fluorescent colors have already been synthesized. However, a white light-emitting material brought about by a broad fluorescence emission cannot be obtained only by changing the structure of the conjugated oligomer.

On the other hand, a method is known in which a light emitting layer that emits a certain light emission color is doped with fluorescent dyes of different colors to change the light emission color of the light emitting layer. For example, in Non-Patent Document 1, when a host material composed of an aluminum complex light-emitting electron transport layer and a hole transport layer that emits green light is doped with a red light-emitting dye, light from two light-emitting materials is mixed to produce yellow light. Has been proven to produce In this case, the dopant is excited by energy transfer or the like from the aluminum complex of the host. Also known is a method of changing a luminescent color using a method in which a carrier block layer is disposed between an electron transporting luminescent layer and a hole transporting luminescent layer, and the respective luminescent colors are mixed (Non-patent Document 2). ). The inventors have achieved white light emission by combining these two methods (Non-patent Document 3).
CWTang, SAVanSiyke, CH Chen, J. Appl. Phys. 27, L268 (1988) J. Kido, C. Ohtaki, K. Hongawa, K. Okuyama, K. Nagai, Jpn. J. ApplPhys. 32, L917 (1993) J. Kido, M. Kimura, K. Nagai, Science, Vol.267, pp1332-1334 (1995)

  However, the above conventional method requires doping of a fluorescent dye, which is not always easy to manufacture, and requires a device having a considerable multilayer structure, so that the manufacturing process becomes complicated or manufactured. There is a problem that the structure of the element is complicated, and it has been desired to achieve white light emission by a simpler method.

The present invention has been made in view of the above circumstances, and a main object thereof is to provide a novel electroluminescent material having a structure different from that of the conventional one having various problems.
Another object of the present invention is that the emission color can be changed by a very simple method without doping a fluorescent dye or making the light emitting layer multi-layered, and in particular, white light emission can be easily achieved. It is to provide an electroluminescent material.
It is a further object of the present invention to provide a light emitting device constructed using the electroluminescent material.

  Thus, the present invention comprises a coordination compound obtained by coordinating a metal ion species to a bridging ligand formed by linking a ligand on both sides of a conjugated oligomer having a fluorescent core, There is provided an organic electroluminescent material characterized in that it emits an emission color different from the emission color of the bridging ligand.

In the organic electroluminescent material having such a structure, the conjugated oligomer itself forms a predetermined fluorescent color, but when a metal ion is coordinated through the ligand, a bridged ligand containing the conjugated oligomer and Complexation is formed between metal ions, cross-linking and / or polymerization occurs, and an emission color different from the emission color originally possessed by the conjugated oligomer is obtained. And in such an organic electroluminescent material, it becomes possible to achieve the luminescent color which cannot be achieved only by using a conjugated oligomer, especially by adjusting the kind and / or concentration of the metal ion species.
In addition, the conjugated oligomer itself can change the emission color by changing the structure. However, unlike other polymers, the conjugated oligomer can easily have a conjugated length of a fixed length. By changing the conjugate length, the emission color emitted by the conjugated oligomer can be easily changed. For example, as shown in the following specific examples, a conjugated oligomer having a predetermined conjugate length is formed by linking oligomers such as oligophenylene and oligothiophene on both sides around a core such as fluorene that forms a predetermined fluorescent color. Then, the fluorescence emission color of the core (blue in the case of fluorene) can be changed, and a ligand such as terpyridine is connected to both ends of the conjugated oligomer to form a bridging ligand, and a metal ion is coordinated to it. When it is made, the luminescent color which cannot be achieved only with a conjugated oligomer is obtained. In particular, by selecting the metal ion species to be coordinated and the concentration thereof, various emission colors such as white, yellow, blue, and orange can be achieved.

からなる群から選択される配位子を表し、
・Ａは

（上式中、Ｒａ、Ｒｂは互いに同一でも異なっていてもよいアルキル基を表す）の蛍光発色を有するフルオレンコアを表し、
・Ｂ_１、Ｂ_２は互いに同一でも異なっていてもよく、

（上式中、Ｒｃ、Ｒｄは、互いに同一でも異なっていてもよく、水素、アルキル基もしくはアルコキシ基を表し、ｎは１〜３の整数を表す）
からなる群から選択されるオリゴマーを表す］
を有する。 As described above, the present invention intends to achieve a desired emission color such as white, yellow, blue, orange, etc. by changing the emission color of the conjugated oligomer by coordinating metal ion species. As long as this purpose is achieved, the structure of the conjugated oligomer, the ligand, and the metal ion species are not limited to specific ones. Basic structure:
L ₁ -B ₁ -AB ₂ -L ₂
[In the above formula,
L ₁ and L ₂ may be the same or different from each other,

Represents a ligand selected from the group consisting of
・ A is

(In the above formula, Ra and Rb represent an alkyl group which may be the same or different from each other) and represent a fluorene core having a fluorescent color development,
B ₁ and B ₂ may be the same or different from each other,

(In the above formula, Rc and Rd may be the same or different from each other, and represent hydrogen, an alkyl group or an alkoxy group, and n represents an integer of 1 to 3)
Represents an oligomer selected from the group consisting of]
Have

（上式中、Ｒ_１はアルキル基、Ｒ_２は水素、アルキル基もしくはアルコキシ基、ｎは１〜３の整数を表す）
からなる群から選択される。 This bridging ligand is more preferably the following specific compound:

(In the above formula, R ₁ represents an alkyl group, R ₂ represents hydrogen, an alkyl group or an alkoxy group, and n represents an integer of 1 to 3)
Selected from the group consisting of

（上式中、Ｍｔは金属イオン種を表し、矩形記号は共役オリゴマーを表す）
のような構造を有していると考えられる。
なお、金属イオン種がテルビウム又はユーロピウムの場合は、配位構造は必ずしも上記の構造とはならないことを付言しておく。 The metal ion species is preferably a metal ion species selected from the group consisting of zinc, aluminum, ruthenium, osmium, terbium, europium, platinum, gold, and iridium. The concentration of the metal ion species is appropriately adjusted according to the desired emission color, but a molar concentration between 0 and 2 times the concentration of the conjugated oligomer is preferable. The light emission of such a coordination compound is very sensitive to the metal ion concentration, and the light emission color varies depending on the amount of metal ion added. For example, in one aspect of achieving white light emission, as will be clarified in the examples described later, when zinc is selected as the metal ion species, the color increases from blue to white and yellow as the concentration of added zinc ions increases. The fluorescent color changes. Therefore, when white light emission is desired, it is necessary to select an appropriate concentration of zinc ions.
For example, when the ligand is terpyridine, the coordination compound formed in the present invention has the following formula:

(In the above formula, Mt represents a metal ion species, and a rectangular symbol represents a conjugated oligomer)
It is thought that it has the following structure.
Note that when the metal ion species is terbium or europium, the coordination structure is not necessarily the above structure.

Furthermore, the present invention also relates to a light emitting device using the organic electroluminescent material, wherein the light emitting device has a hole injection layer and a light emitting layer comprising the organic electroluminescent material according to the present invention disposed between an anode and a cathode. Then, a voltage is applied between the anode and the cathode to cause electroluminescence.
Furthermore, the present invention relates to a method for manufacturing a light-emitting device using the above organic electroluminescent material. A ligand is connected to both sides of a conjugated oligomer having a fluorescent core according to the present invention on a hole injection layer. A light-emitting layer is formed by applying a solution containing a bridging ligand and a metal ion species.
In the above solution, the concentration of the metal ion species is not more than twice the molar concentration of the bridging ligand.

  According to the present invention, a novel electroluminescent material having a structure different from the conventional one having various defects is provided. And in the organic electroluminescent material and the light emitting device according to the present invention, the emission color can be changed by a very simple method without doping the fluorescent dye or making the light emitting layer multilayered as in the past, Various emission colors such as yellow, blue, orange and white can be easily achieved. In particular, white light emission can be expected to be used in a wider range of applications such as liquid crystal backlights and direct white fluorescent lighting fixtures, as compared to organic light-emitting materials of other emission colors.

The organic electroluminescent material of the present invention comprises a step of producing a bridging ligand formed by linking a ligand on both sides of a conjugated oligomer having a fluorescent core, and a metal ion species is added to the produced bridging ligand. And a step of producing a coordination compound by addition.
Various conjugated oligomers containing a ligand have been conventionally produced, and can be produced by a conventional method in the present invention.

（上式中、Ｒａ、Ｒｂは互いに同一でも異なっていてもよい、好ましくは炭素数が４〜１８の直鎖状又は分岐状アルキル鎖を表す）
この化合物は常法によって調製するか又は市販品を用いることができる。 As the core for fluorescent color development, a color development core having any structure may be used, but preferably, fluorene known as a blue light emitting material having excellent film forming properties is used.
The core that emits blue light and is made of fluorene is preferably represented by the following formula.

(In the above formula, Ra and Rb may be the same or different from each other, and preferably represent a linear or branched alkyl chain having 4 to 18 carbon atoms)
This compound can be prepared by a conventional method or a commercially available product can be used.

ついで、次の反応経路：

あるいは、

に従って、連結鎖の長さに応じて、ベンズアルデヒド類、チオフェンカルバルデヒド類等にアセチルピリジンを反応させ、その生成物に、更に前述のようにして調製したピリジニウム化合物を反応させて、フェニルターピリジン類、チオフェニルターピリジン類等のターピリジンと連結鎖とからなる化合物を合成する。 On the other hand, a bridging ligand in which terpyridine or the like serving as a ligand is connected to both sides of the core via a connecting chain is synthesized. For example, a compound containing terpyridine as a ligand and a linking chain having a predetermined length is first synthesized. As an example of this synthetic route, for example, 1- (2-oxo-2-pyridin-2-yl-ethyl) -pyridinium is synthesized according to the reaction of the following formula.

Then the following reaction pathway:

Or

In accordance with the length of the linking chain, benzaldehydes, thiophenecarbaldehydes and the like are reacted with acetylpyridine, and the product is further reacted with the pyridinium compound prepared as described above to obtain phenylterpyridines. Then, a compound composed of terpyridine such as thiophenyl terpyridines and a linking chain is synthesized.

The compound consisting of a ligand such as terpyridine and a linking chain is reacted with the aforementioned core compound to obtain the following various conjugated oligomers having ligands such as terpyridine at both ends (wherein , R ₁ , R _{2 and the} like are as defined above.

（上式中、Ｍｔは金属イオン種を表し、矩形記号は共役オリゴマーを表す）
この錯体は、金属イオンの種類によって異なった蛍光発色をなす。従って、前述のコアと連結鎖の種類、共役長の選択に併せて、金属イオン種として如何なる種類のものを選ぶかによって、発光色が変化する。
しかして、添加することができる金属イオン種は、亜鉛、アルミニウム、ルテニウム、オスミウム、テルビウム、ユーロピウム、白金、金、イリジウムからなる群から好適に選択され、所望される発光色に応じて適宜選択される。また金属イオン種の種類に加えて、金属イオン種の濃度もまた発光色に影響を及ぼす。よって、所望される発光色に応じて金属イオン種の濃度が決定される。前述の亜鉛を選んだ場合、亜鉛イオンの濃度は共役オリゴマーの濃度の２倍以下のモル濃度に設定する。 The conjugated oligomer thus obtained exhibits luminescence derived from fluorene as a core and luminescence derived from the oligomer structure. Even if the core and the oligomer are of the same type, the fluorescence color is greatly different if the length of the linking chain is changed.
In the present invention, as a result of addition of a metal ion species to such a conjugated oligomer, a metal ion is coordinated to a ligand such as terpyridine to form a bisterpyridine metal complex having a structure represented by the following formula, for example. Is done.

(In the above formula, Mt represents a metal ion species, and a rectangular symbol represents a conjugated oligomer)
This complex exhibits different fluorescence colors depending on the type of metal ion. Accordingly, the emission color changes depending on what kind of metal ion species is selected in conjunction with the selection of the core and linking chain type and the conjugate length.
Thus, the metal ion species that can be added is preferably selected from the group consisting of zinc, aluminum, ruthenium, osmium, terbium, europium, platinum, gold, and iridium, and appropriately selected according to the desired emission color. The In addition to the type of metal ion species, the concentration of metal ion species also affects the emission color. Therefore, the concentration of the metal ion species is determined according to the desired emission color. When the aforementioned zinc is selected, the concentration of zinc ions is set to a molar concentration not more than twice the concentration of the conjugated oligomer.

The organic electroluminescent material according to the present invention described above finds various uses in electronic devices, and is particularly suitable for constructing light-emitting elements that are regarded as promising materials for display devices. As this kind of light emitting element, those having various structures are conventionally known, and the organic electroluminescent material according to the present invention can be used for those having any structure.
The light emitting device will be described in detail. In the light emitting device, a light emitting layer containing the organic electroluminescent material according to the present invention is disposed between an anode and a cathode, and a voltage is applied between the anode and the cathode to perform electroluminescence. Typically, an anode 2 such as a transparent ITO (indium / tin oxide) electrode is formed on a glass substrate 1, as shown in FIG. A hole injection layer 3 composed of P or the like is disposed, and a light emitting layer 4 made of the organic electroluminescent material according to the present invention is laminated on the hole injection layer 3, and calcium is formed on the light emitting layer 4. And a multilayer structure in which a cathode 5 made of magnesium, aluminum or the like is formed. Then, holes are injected from the anode 2 toward the hole injection layer 3, and electrons are injected from the cathode 5 toward the light emitting layer 4. The electrons and holes are combined in the light emitting layer 4 to emit light.

  The light emitting device according to the present invention is not limited to the basic structure shown in FIG. 1, and may have various structures. For example, as shown in FIG. 2, the light emitting element has a structure further including a carrier block layer. It can also be. In FIG. 2, 6 is a glass substrate, 7 is an ITO anode, 8 is a hole transporting light emitting layer, 9 is a carrier block layer, 10 is an electron transporting light emitting layer, and 11 is a cathode.

先ず、ドラフト内、Ｎ_２気流下で、ピリジン４５ｍｌ（５．５６×１０^−１ｍｏｌ）、２-アセチルピリジン２０．４３ｍｌ（１．８２×１０^−１ｍｏｌ）、ヨウ素４６．２２ｇ（１．８２×１０^−１ｍｏｌ）を１００℃で１．５時間攪拌還流を行った。その後、水に溶解させて熱濾過を行った。その水溶液を氷浴で再結晶させた後、析出物を吸引濾過によって１-(２-オキソ-２-ピリジン-２-イル-エチル)-ピリジニウム・ヨウ化物を合成した。収量は４０．３１ｇ（６７．９％）であった。
ついで、塩入り氷浴中で、４-ブロモベンズアルデヒド１ｇ（５．４０×１０^−３ｍｏｌ）、２-アセチルピリジン０．６１ｍｌ（５．４０×１０^−３ｍｏｌ）を１０ｍｌのＭｅＯＨに溶かし攪拌した。ここに、３ｗｔ％のＮａＯＨ／ＭｅＯＨ ７ｍｌ（ＮａＯＨ ０．２５ｇ／ＭｅＯＨ １０ｍｌで作成したもの）を滴下し、３時間冷却攪拌した後、冷凍庫で一晩冷却を行った。その後、酢酸アンモニウム５．２１ｇ（６．７６×１０^−２ｍｏｌ）、１-(２-オキソ-２-ピリジン-２-イル-エチル)-ピリジニウム・ヨウ化物１．７６ｇ（５．４０×１０^−３ｍｏｌ）を加えた後に加熱をして、一晩攪拌還流を行った。その後、アルミナによるカラム処理 (ジクロロメタン)で精製、メタノールで再結晶し、析出物を吸引濾過して４'-(４-ブロモ-フェニル)-[２,２';６',３"]ターピリジンを得た。収量は０．８０ｇ（３８．１％）であった。 Hereinafter, the present invention will be described in detail by way of examples. Of course, the present invention is not limited to these examples.
<Example 1>
Synthesis of 9,9-dihexyl-2,7-di {(4'-phenyl)-[2,2 ';6', 3 "] terpyridine} fluorene (Compound 1) a) 4 '-(4-Bromo- Synthesis of phenyl)-[2,2 ';6', 3 "] terpyridine

First, 45 ml (5.56 × 10 ⁻¹ mol) of pyridine, 20.43 ml (1.82 × 10 ⁻¹ mol) of 2-acetylpyridine, 46.22 g of iodine (1.82) under a N ₂ stream in a draft. × 10 ⁻¹ mol) was stirred and refluxed at 100 ° C. for 1.5 hours. Thereafter, it was dissolved in water and subjected to hot filtration. The aqueous solution was recrystallized in an ice bath, and 1- (2-oxo-2-pyridin-2-yl-ethyl) -pyridinium iodide was synthesized by suction filtration of the precipitate. The yield was 40.31 g (67.9%).
Then, in a salt-containing ice bath, 4-bromobenzaldehyde ^{1g (5.40 × 10 -3 mol)} , 2- acetylpyridine 0.61ml of (5.40 × ¹⁰ -3 mol) was stirred dissolved in MeOH and 10ml . Here, 7 ml of 3 wt% NaOH / MeOH (prepared with 10 ml of NaOH 0.25 g / MeOH) was dropped, and the mixture was cooled and stirred for 3 hours, and then cooled overnight in a freezer. Then, ammonium acetate ^{5.21g (6.76 × 10 -2 mol)} , 1- (2- oxo-2-pyridin-2-yl - ethyl) - pyridinium iodide 1.76 g (5.40 × 10 ^{- 3} mol) was added, followed by heating, followed by stirring and refluxing overnight. Then, purification by column treatment with alumina (dichloromethane), recrystallization with methanol, and the precipitate was filtered with suction to give 4 '-(4-bromo-phenyl)-[2,2'; 6 ', 3 "] terpyridine. The yield was 0.80 g (38.1%).

Ｎ_２気流下で、４'-(４-ブロモ-フェニル)-[２,２';６',３"]ターピリジン０．４０ｇ（１．０４×１０^−３ｍｏｌ）、９,９-ジヘキシル-２,７-ジボロン酸フルオレン０．２０ｇ（４．７４×１０^−４ｍｏｌ）をＴＨＦ４ｍｌ、トルエン４ｍｌ、１Ｍ Ｋ_２ＣＯ_３ ４ｍｌに溶解させ、３０分間脱気を行った。その後、Ｐｄ(ＰＰｈ_３)_４ ３６ｍｇを加え、６０〜７０℃で３６時間攪拌還流を行った。それから、クロロホルム／水で分液、乾燥、減圧濃縮を行った。その後、高速液体クロマトグラフィー（クロロホルム）によって、表題化合物１を得た。収量は０．２５ｇ（５５．５％）であった。
MALDI-TOF-Ms (dithranol) m/z 950.49 (C₆₇H₆₀N₆に対する算定値：949.23)
¹H NMR (400MHz,CDCl₃) δ= 8.69 (s,4H,ArH), 8.69 (d,4H,ArH), 8.69 (d,4H,ArH), 8.06 (d,4H,ArH),8.04 (m,4H,ArH), 7.83 (m,6H,ArH), 7.70 (m,4H,ArH), 7.67 (m,4H,ArH), 2.12 (m,4H,-CH_2-), 1.11 (s,12H,-CH₂-), 0.95 (m,10H,-CH₂-,-CH₃) b) Synthesis of 9,9-dihexyl-2,7-di {(4'-phenyl)-[2,2 ';6', 3 "] terpyridine} fluorene

4 '-(4-Bromo-phenyl)-[2,2'; 6 ', 3 "] terpyridine 0.40 g (1.04 × 10 ^-3 mol), 9,9-dihexyl- under N ₂ stream Fluorene 2,7-diboronic acid 0.20 g (4.74 × 10 ⁻⁴ mol) was dissolved in 4 ml of THF, 4 ml of toluene, 4 ml of 1M K ₂ CO ₃ and degassed for 30 minutes, and then Pd (PPh _{3 4} ) 36 mg was added, and the mixture was stirred and refluxed at 60 to 70 ° C. for 36 hours, and then separated, dried and concentrated under reduced pressure with chloroform / water, and then subjected to high performance liquid chromatography (chloroform) to give the title compound 1 The yield was 0.25 g (55.5%).
MALDI-TOF-Ms (dithranol) m / z 950.49 (calculated value for C ₆₇ H ₆₀ N ₆ : 949.23)
¹ H NMR (400MHz, CDCl ₃ ) δ = 8.69 (s, 4H, ArH), 8.69 (d, 4H, ArH), 8.69 (d, 4H, ArH), 8.06 (d, 4H, ArH), 8.04 (m , 4H, ArH), 7.83 (m, 6H, ArH), 7.70 (m, 4H, ArH), 7.67 (m, 4H, ArH), 2.12 (m, 4H, -CH _2- ), 1.11 (s, 12H , -CH _2- ), 0.95 (m, 10H, -CH ₂ -,-CH ₃ )

塩入り氷浴中で、５-ブロモ-チオフェン-２-カルバルデヒド１ｇ（５．２３×１０^−３ｍｏｌ）、２-アセチルピリジン０．５９ｍｌ（５．２３×１０^−３ｍｏｌ）をＭｅＯＨ １０ｍｌに溶かし攪拌した。ここに、３ｗｔ％ ＮａＯＨ／ＭｅＯＨ ７ｍｌ（ＮａＯＨ ０．２５g／ＭｅＯＨ １０ｍｌで作成したもの）を滴下し、３時間冷却攪拌した後、冷凍庫で一晩冷却を行った。その後、酢酸アンモニウム５．０４ｇ（６．５４×１０^−２ｍｏｌ）、1-(２-オキソ-２-ピリジン-２-イル-エチル)-ピリジニウム・ヨウ化物１．７１ｇ (５．２３×１０^−３ｍｏｌ)を加えた後に加熱をして、一晩攪拌還流を行った。その後、アルミナによるカラム処理 (ジクロロメタン)で精製、メタノールで再結晶し、析出物を吸引濾過して４'-(５-ブロモ-チオフェン-２-イル)-[２,２';６',２"]ターピリジンを得た。収量は１．２０ｇ（５８．０％）であった。
¹H NMR (400MHz,CDCl₃) δ= 8.73 (d,2H,ArH), 8.61 (d,2H,ArH), 8.59 (s,2H,ArH), 7.86 (m,2H,ArH) , 7.51(d,1H,ArH), 7.36 (m,2H,ArH),7.12 (d,1H,ArH)
¹²C NMR (400MHz,CDCl₃) δ= 156.24, 155.84, 149.15, 136.88, 131.19, 125.97, 124.00, 121.31, 116.68, 77.34, 77.02, 76.70 <Example 2>
Synthesis of 9,9-dihexyl-2,7-di {(4'-thiophen-2-yl)-[2,2 ';6', 2 "] terpyridine} fluorene (compound 2) (a) 4'- Synthesis of (5-Bromo-thiophen-2-yl)-[2,2 ';6', 2 "] terpyridine

A salt-containing ice bath, 5-bromo - thiophene-2-carbaldehyde ^{1g (5.23 × 10 -3 mol)} , 2- acetylpyridine 0.59ml of (5.23 × ¹⁰ -3 mol) in MeOH 10 ml Dissolved and stirred. 7 ml of 3 wt% NaOH / MeOH (prepared with 10 ml of NaOH 0.25 g / MeOH) was added dropwise thereto, and the mixture was cooled and stirred for 3 hours, and then cooled overnight in a freezer. Then, ammonium acetate ^{5.04g (6.54 × 10 -2 mol)} , 1- (2- oxo-2-pyridin-2-yl - ethyl) - pyridinium iodide 1.71 g (5.23 × 10 ^{- 3} mol) was added, followed by heating, followed by stirring and refluxing overnight. Then, it is purified by column treatment with alumina (dichloromethane), recrystallized from methanol, and the precipitate is subjected to suction filtration to give 4 '-(5-bromo-thiophen-2-yl)-[2,2'; 6 ', 2 "] Terpyridine was obtained, and the yield was 1.20 g (58.0%).
¹ H NMR (400MHz, CDCl ₃ ) δ = 8.73 (d, 2H, ArH), 8.61 (d, 2H, ArH), 8.59 (s, 2H, ArH), 7.86 (m, 2H, ArH), 7.51 (d , 1H, ArH), 7.36 (m, 2H, ArH), 7.12 (d, 1H, ArH)
¹² C NMR (400 MHz, CDCl ₃ ) δ = 156.24, 155.84, 149.15, 136.88, 131.19, 125.97, 124.00, 121.31, 116.68, 77.34, 77.02, 76.70

Ｎ_２気流下で、４'-(５-ブロモ-チオフェン-２-イル)-[２,２';６',２"]ターピリジン ０．２３ｇ（５．７９×１０^−４ｍｏｌ）、９,９-ジヘキシル-２,７-ジボロン酸フルオレン０．１１g（２．６１×１０^−４ｍｏｌ）をＴＨＦ３ｍｌ、トルエン３ｍｌ、１Ｍ Ｋ_２ＣＯ_３ ３ｍｌに溶解させ、３０分間脱気を行った。その後、Ｐｄ(ＰＰｈ_３)_４ １０ｍｇを加え、６０〜７０℃で３６時間攪拌還流を行った。それから、クロロホルム/水で分液、乾燥、減圧濃縮を行った。その後、高速液体クロマトグラフィー (クロロホルム)によって、表題化合物２を得た。収量は０．１０ｇ (４０．０％)であった。
MALDI-TOF-Ms (dithranol) m/z 962.09 (C₆₃H₅₆N₆S₂に対する算定値：961.29)
¹H NMR (400MHz,CDCl₃) δ= 8.78 (d,4H,ArH), 8.74 (s,4H,ArH), 8.67 (d,4H,ArH), 7.90 (m,4H,ArH), 7.81 (d,2H,ArH), 7.73 (m,4H,ArH), 7.66 (s,2H,ArH), 7.47 (d,2H,ArH), 7.36 (m,4H,ArH), 2.10 (m,4H,-CH₂-), 1.11 (m,12H,-CH₂-), 0.77 (m,10H,-CH₂-,-CH₃)
¹²C NMR (400MHz,CDCl₃) δ= 156.13, 151.99, 149.19, 146.79, 143.33, 140.70, 140.57, 136.88, 132.98, 126.88, 124.91, 124.10, 123.92, 121.38, 120.34, 120.13, 116.68, 55.47, 40.53, 31.52, 29.73, 23.85, 22.62, 14.01 (B) Synthesis of 9,9-dihexyl-2,7-di {(4'-thiophen-2-yl)-[2,2 ';6', 2 "] terpyridine} fluorene

Under N ₂ stream, 0.23 g (5.79 × 10 ⁻⁴ mol) of 4 ′-(5-bromo-thiophen-2-yl)-[2,2 ′; 6 ′, 2 ″] terpyridine, 9, 9-dihexyl-2,7-diboronic acid fluorene (0.11 g, 2.61 × 10 ⁻⁴ mol) was dissolved in THF (3 ml), toluene (3 ml), and 1M K ₂ CO _{3 (} 3 ml), followed by deaeration for 30 minutes. 10 mg of Pd (PPh ₃ ) ₄ was added, and the mixture was stirred and refluxed for 36 hours at 60 to 70 ° C. Then, liquid separation with chloroform / water, drying and concentration under reduced pressure were performed, followed by high performance liquid chromatography (chloroform). To give the title compound 2. The yield was 0.10 g (40.0%).
MALDI-TOF-Ms (dithranol) m / z 962.09 (calculated value for C ₆₃ H ₅₆ N ₆ S ₂ : 961.29)
¹ H NMR (400MHz, CDCl ₃ ) δ = 8.78 (d, 4H, ArH), 8.74 (s, 4H, ArH), 8.67 (d, 4H, ArH), 7.90 (m, 4H, ArH), 7.81 (d , 2H, ArH), 7.73 (m, 4H, ArH), 7.66 (s, 2H, ArH), 7.47 (d, 2H, ArH), 7.36 (m, 4H, ArH), 2.10 (m, 4H, -CH _2- ), 1.11 (m, 12H, -CH _2- ), 0.77 (m, 10H, -CH ₂ -,-CH ₃ )
¹² C NMR (400 MHz, CDCl ₃ ) δ = 156.13, 151.99, 149.19, 146.79, 143.33, 140.70, 140.57, 136.88, 132.98, 126.88, 124.91, 124.10, 123.92, 121.38, 120.34, 120.13, 116.68, 55.47, 40.53, 31.52 , 29.73, 23.85, 22.62, 14.01

塩入り氷浴中で、５-ブロモ-[２,２']ビチオフェニル-５-カルバルデヒド １ｇ （３．６６×１０^−３ｍｏｌ）、２-アセチルピリジン０．４１ｍｌ（３．６６×１０^−３ｍｏｌ）をMeOH １０ｍｌに溶かし攪拌した。ここに、３ｗｔ％ ＮａＯＨ／ＭｅＯＨ ７ｍｌ （ＮａＯＨ０．２５ｇ／ＭｅＯＨ１０ｍｌで作成したもの)を滴下し、３時間冷却攪拌した後、冷凍庫で一晩冷却を行った。その後、酢酸アンモニウム３．５３ｇ（４．５８×１０^−２ｍｏｌ）、１-(２-オキソ-２-ピリジン-２-イル-エチル)-ピリジニウム;ヨウ化物１．１９ｇ（３．６６×１０^−３ｍｏｌ）を加えた後に加熱をして、一晩攪拌還流を行った。その後、アルミナによるカラム処理 (ジクロロメタン)で精製、メタノールで再結晶し、析出物を吸引濾過して４'-(５'-ブロモ-[２,２']ビチオフェニル-５-イル)-[２,２';６',２"]ターピリジンを得た。収量は０．８４ｇ（４８．０％）であった。
¹H NMR (400MHz,CDCl₃) δ= 8.75 (d,2H,ArH), 8.63 (d,4H,ArH), 7.87 (m,2H,ArH), 7.67 (d,1H,ArH), 7.36 (m,2H,ArH), 7.15 (d,1H,ArH), 7.00 (s,2H,ArH)
¹²C NMR (400MHz,CDCl₃) δ= 156.16, 155.95, 149.15, 145.89, 136.87, 130.83, 126.56, 124.92, 124.31, 123.96, 121.33, 116.70, 77.33, 77.01, 76.70 <Example 3>
Synthesis of 9,9-dihexyl-2,7-di {[2,2 ′] bithiophenyl-5-yl}-[2,2 ′; 6 ′, 2 ″] terpyridine} fluorene (compound 3) (a) 4 Synthesis of '-(5'-Bromo- [2,2'] bithiophenyl-5-yl)-[2,2 ';6', 2 "] terpyridine

A salt-containing ice bath, 5-bromo - [2,2 '] bithiophenyl-5-carbaldehyde ^{1g (3.66 × 10 -3 mol)} , 2- acetylpyridine 0.41ml (3.66 × ^{10 -3} mol) was dissolved in 10 ml of MeOH and stirred. Here, 7 ml of 3 wt% NaOH / MeOH (prepared with NaOH 0.25 g / MeOH 10 ml) was added dropwise, and the mixture was cooled and stirred for 3 hours, and then cooled overnight in a freezer. Then 3.53 g (4.58 × 10 ⁻² mol) of ammonium acetate, 1- (2-oxo-2-pyridin-2-yl-ethyl) -pyridinium; 1.19 g of iodide (3.66 × 10 ^{− 3} mol) was added, followed by heating, followed by stirring and refluxing overnight. Thereafter, purification by column treatment with alumina (dichloromethane), recrystallization with methanol, and the precipitate was filtered with suction, and 4 ′-(5′-bromo- [2,2 ′] bithiophenyl-5-yl)-[2, 2 ′; 6 ′, 2 ″] terpyridine was obtained. The yield was 0.84 g (48.0%).
¹ H NMR (400MHz, CDCl ₃ ) δ = 8.75 (d, 2H, ArH), 8.63 (d, 4H, ArH), 7.87 (m, 2H, ArH), 7.67 (d, 1H, ArH), 7.36 (m , 2H, ArH), 7.15 (d, 1H, ArH), 7.00 (s, 2H, ArH)
¹² C NMR (400 MHz, CDCl ₃ ) δ = 156.16, 155.95, 149.15, 145.89, 136.87, 130.83, 126.56, 124.92, 124.31, 123.96, 121.33, 116.70, 77.33, 77.01, 76.70

Ｎ_２気流下で、４'-(５'-ブロモ-[２,２']ビチオフェニル-５-イル)-[２,２';６',２"]ターピリジン ０．１０ｇ（２．１０×１０^−４ｍｏｌ）、９,９-ジヘキシル-2,7-ジボロン酸フルオレン４０ｍｇ（９．５４×１０^−５ｍｏｌ）をＴＨＦ３ｍｌ、トルエン３ｍｌ、１Ｍ Ｋ_２ＣＯ_３３ｍｌに溶解させ、３０分間脱気を行った。その後、Ｐｄ(ＰＰｈ_３)_４ １０ｍｇを加え、６０〜７０℃で３６時間攪拌還流を行った。それから、クロロホルム／水で分液、乾燥、減圧濃縮を行った。その後、高速液体クロマトグラフィー (クロロホルム)によって、表題化合物３を得た。収量は３０ｍｇ（２８．０％）であった。
MALDI-TOF-Ms (dithranol) m/z 1126.08 (C₇₁H₆₀N₆S₄ に対する算定値：1125.54)
¹H NMR (400MHz,CDCl₃) δ= 8.76 (d,4H,ArH), 8.70 (s,4H,ArH), 8.49 (d,4H,ArH), 7.88 (m,4H,ArH), 7.72 (m,2H,ArH), 7.70 (s,2H,ArH), 7.60 (m,2H,ArH), 7.58 (d,2H,ArH), 7.38 (m,6H,ArH), 7.36 (d,4H,ArH), 2.04 (m,4H,-CH₂-), 1.11 (m,12H,-CH₂-), 0.77 (m,10H,-CH₂-,-CH₃)。 (B) Synthesis of 9,9-dihexyl-2,7-di {[2,2 ′] bithiophenyl-5-yl}-[2,2 ′; 6 ′, 2 ″] terpyridine} fluorene

Under N ₂ stream, 0.10 g (2.10 × 10) of 4 ′-(5′-bromo- [2,2 ′] bithiophenyl-5-yl)-[2,2 ′; 6 ′, 2 ″] terpyridine ^-4 mol), 9,9-dihexyl-2,7-diboronic acid fluorene 40 mg (9.54 × 10 ⁻⁵ mol) is dissolved in THF 3 ml, toluene 3 ml, 1M K ₂ CO ₃ 3 ml and degassed for 30 minutes. Thereafter, 10 mg of Pd (PPh ₃ ) ₄ was added, and the mixture was stirred and refluxed at 60 to 70 ° C. for 36 hours, followed by liquid separation with chloroform / water, drying, and concentration under reduced pressure. Chromatography (chloroform) gave the title compound 3. Yield 30 mg (28.0%).
MALDI-TOF-Ms (dithranol) m / z 1126.08 (calculated value for C ₇₁ H ₆₀ N ₆ S ₄ : 1125.54)
¹ H NMR (400MHz, CDCl ₃ ) δ = 8.76 (d, 4H, ArH), 8.70 (s, 4H, ArH), 8.49 (d, 4H, ArH), 7.88 (m, 4H, ArH), 7.72 (m , 2H, ArH), 7.70 (s, 2H, ArH), 7.60 (m, 2H, ArH), 7.58 (d, 2H, ArH), 7.38 (m, 6H, ArH), 7.36 (d, 4H, ArH) , 2.04 (m, 4H, -CH _2- ), 1.11 (m, 12H, -CH _2- ), 0.77 (m, 10H, -CH ₂ -,-CH ₃ ).

塩入り氷浴中で、５"-ブロモ-２,２';５',２'-ターチオフェン-５-カルボキシアルデヒド０．３ｇ（８．４４×１０^−４ｍｏｌ）,２-アセチルピリジン０．０９４ｍｌ（８．４４×１０^−４ｍｏｌ）をＭｅＯＨ ５ｍｌに溶かし攪拌した。ここに、３ｗｔ％ ＮａＯＨ／ＭｅＯＨ １ｍｌ（ＮａＯＨ ０．２５ｇ／ＭｅＯＨ １０ｍｌで作成したもの）を滴下し、３時間冷却攪拌した後、冷凍庫で一晩冷却を行った。その後、酢酸アンモニウム２g（２．６０×１０^−２ｍｏｌ）、１-(２-オキソ-２-ピリジン-２-イル-エチル)-ピリジニウム・ヨウ化物０．２７ｇ（８．４４×１０^−４ｍｏｌ）を加えた後に加熱をして、一晩攪拌還流を行った。その後、アルミナによるカラム処理 (ジクロロメタン)を行い、２-メトキシエタノールで再結晶し、析出物を吸引濾過して４'-(５"-ブロモ-[２,２';５',２"]ターチオフェン-５-イル)-[２,２';６',２"]ターピリジンを得た。収量は０．２１ｇ（４４．６％）であった。
¹H NMR (400MHz,CDCl₃) δ= 8.66 (d,2H,ArH), 8.64 (s,2H,ArH), 8.63 (d,2H,ArH), 7.86 (m,2H,ArH),7.70 (d,1H,ArH), 7.38 (m,2H,ArH), 7.23 (d,1H,ArH), 7.16 (d,1H,ArH),7.05 (d,1H,ArH), 6.99 (d,1H,ArH), 6.94 (d,1H,ArH)。 <Example 4>
9,9-dihexyl-2,7-di {4 '-([2,2'; 5 ', 2 "] terthiophen-5-yl)-[2,2'; 6 ', 2"] terpyridine} Synthesis of fluorene (compound 4) (a) 4 '-(5 "-bromo- [2,2'; 5 ', 2"] terthiophen-5-yl)-[2,2'; 6 ', 2 " Synthesis of terpyridine

In a salted ice bath, 0.3 g (8.44 × 10 ⁻⁴ mol) of 5 ″ -bromo-2,2 ′; 5 ′, 2′-terthiophene-5-carboxaldehyde, 0.2 acetylpyridine 094 ml (8.44 × 10 ⁻⁴ mol) was dissolved in 5 ml of MeOH and stirred, and 1 ml of 3 wt% NaOH / MeOH (prepared with 10 ml of NaOH 0.25 g / MeOH) was added dropwise and stirred for 3 hours. Thereafter, the mixture was cooled overnight in a freezer, and then 2 g (2.60 × 10 ⁻² mol) of ammonium acetate, 1- (2-oxo-2-pyridin-2-yl-ethyl) -pyridinium iodide 0 .27 g (8.44 × 10 ⁻⁴ mol) was added, and the mixture was heated and stirred and refluxed overnight, followed by column treatment with alumina (dichloromethane) and recrystallization with 2-methoxyethanol. Sucking precipitates Filtered and 4 '- (5 "- bromo - [2,2'; 5 ', 2"] terphenyl thiophen-5-yl) - [2,2'; 6 ', 2 "] was obtained terpyridine. The yield was 0.21 g (44.6%).
¹ H NMR (400MHz, CDCl ₃ ) δ = 8.66 (d, 2H, ArH), 8.64 (s, 2H, ArH), 8.63 (d, 2H, ArH), 7.86 (m, 2H, ArH), 7.70 (d , 1H, ArH), 7.38 (m, 2H, ArH), 7.23 (d, 1H, ArH), 7.16 (d, 1H, ArH), 7.05 (d, 1H, ArH), 6.99 (d, 1H, ArH) , 6.94 (d, 1H, ArH).

Ｎ_２気流下で、４'-(５"-ブロモ-[２,２';５',２"]ターチオフェン-５-イル)-[２,２';６',２"]ターピリジン０．１ｇ（１．７９×１０^−４ｍｏｌ）、９,９-ジヘキシル-２,７-ジボロン酸フルオレン３４．３ｍｇ（８．１４×１０^−５ｍｏｌ）をＴＨＦ５ｍｌ、トルエン５ｍｌ、１Ｍ Ｋ_２ＣＯ_３ ５ｍｌに溶解させ、３０分間脱気を行った。その後、Ｐｄ(ＰＰｈ_３)_４ ２０ｍｇを加え、６０〜７０℃で３６時間攪拌還流を行った。それから、クロロホルム/水で分液、乾燥、減圧濃縮を行った。その後、高速液体クロマトグラフィー（クロロホルム）によって、表題化合物４を得た。収量は７ｍｇ（６．７％）であった。
MALDI-TOF-Ms (dithranol) m/z 1290.68 (C₇₉H₆₄N₆S₆ に対する算定値：1289.79)
¹H NMR (400MHz,CDCl₃) δ= 8.76 (d,4H,ArH), 8.68 (s,4H,ArH), 8.66 (d,4H,ArH), 7.90 (m,4H,ArH),7.72 (m,2H,ArH), 7.68 (s,2H,ArH), 7.61 (d,2H,ArH), 7.57 (s,2H,ArH),7.38 (m,4H,ArH), 7.37 (d,2H,ArH), 7.32 (s,2H,ArH), 7.21 (m,4H,ArH),7.16 (d,2H,ArH), 0.89 (m,20H,-CH₂-), 0.77 (m,6H,-CH₃)。 (B) 9,9-dihexyl-2,7-di {4'- ([2,2 ';5', 2 "] terthiophen-5-yl)-[2,2 ';6',2" ] Terpyridine} fluorene synthesis

4 '-(5 "-Bromo- [2,2'; 5 ', 2"] terthiophen-5-yl)-[2,2'; 6 ', 2 "] terpyridine under N ₂ stream. 1 g (1.79 × 10 ⁻⁴ mol), 9,9-dihexyl-2,7-diboronic acid fluorene (34.3 mg, 8.14 × 10 ⁻⁵ mol) in THF 5 ml, toluene 5 ml, 1M K ₂ CO ₃ 5 ml Then, 20 mg of Pd (PPh ₃ ) ₄ was added, and the mixture was stirred and refluxed at 60 to 70 ° C. for 36 hours, and then separated with chloroform / water, dried, and concentrated under reduced pressure. The title compound 4 was then obtained by high performance liquid chromatography (chloroform), and the yield was 7 mg (6.7%).
MALDI-TOF-Ms (dithranol) m / z 1290.68 (calculated value for C ₇₉ H ₆₄ N ₆ S ₆ : 1289.79)
¹ H NMR (400MHz, CDCl ₃ ) δ = 8.76 (d, 4H, ArH), 8.68 (s, 4H, ArH), 8.66 (d, 4H, ArH), 7.90 (m, 4H, ArH), 7.72 (m , 2H, ArH), 7.68 (s, 2H, ArH), 7.61 (d, 2H, ArH), 7.57 (s, 2H, ArH), 7.38 (m, 4H, ArH), 7.37 (d, 2H, ArH) , 7.32 (s, 2H, ArH), 7.21 (m, 4H, ArH), 7.16 (d, 2H, ArH), 0.89 (m, 20H, -CH _2- ), 0.77 (m, 6H, -CH ₃ ) .

<Example 5>
Measurement of Visible Absorption Spectrum and Fluorescence Spectrum of Each Compound The compounds 1 to 4 prepared in Examples 1 to 4 were measured for visible absorption spectrum in dichloromethane. The results are shown in FIG. Absorption derived from fluorene was observed around 280 nm for all the compounds, and an absorption peak derived from the oligomer structure was further observed. Compound 1 showed 350 nm, and compounds 2, 3, and 4 showed red shifts of absorption maximums gradually increasing to 401 nm, 430 nm, and 447 nm as the number of thiophenes increased.
In addition, the fluorescence spectrum was measured in dichloromethane. The results are shown in FIG. As can be seen from FIG. 4, Compound 1 showed strong fluorescence at 411 nm. In compounds 2, 3, and 4, emission peaks were observed at 477 nm, 490 nm, and 513 nm, respectively, and it became clear that the fluorescent color was greatly different depending on the structure of the spacer connecting terpyridine.

次に、各化合物１〜４について蛍光スペクトル測定を行った。結果を図７に示す。各図から分かるように、全ての化合物で、鉄イオンの添加とともに蛍光ピークの減少が見られた。そして、鉄イオンの添加量が化合物と等モル量となったところで、ほぼ完全に蛍光が観測されなくなった。これらのことから、鉄イオンの添加によって、配位結合による連続した超分子ポリマーが形成されたことが示唆される。 <Example 6>
Measurement of visible absorption spectrum and fluorescence spectrum when Fe ²⁺ was added For each compound 1 to 4, a visible absorption spectrum was measured in dichloromethane. The results are shown in FIGS. When Fe ²⁺ was added to the synthesized conjugated oligomer, an MLCT band indicating the formation of a bisterpyridine iron complex was observed. Further, when the amount of iron ion added was equimolar with the conjugated oligomer, the MLCT band was not increased. In addition, the wavelength of the absorption maximum in the MLCT band changed depending on the structure of the conjugated oligomer as a spacer. From this, it was found that the electronic interaction between iron complexes can be controlled by changing the spacer structure.

Next, the fluorescence spectrum measurement was performed about each compound 1-4. The results are shown in FIG. As can be seen from each figure, the fluorescence peak decreased with the addition of iron ions in all the compounds. Then, when the amount of iron ion added was equimolar with the compound, fluorescence was not observed almost completely. From these, it is suggested that the addition of iron ions formed a continuous supramolecular polymer due to coordination bonds.

<Example 7>
Subsequently, a visible absorption spectrum was measured when Zn ²⁺ was added to each compound. The results are shown in FIGS. Note that λ _max shown in the table below is an absorption maximum after addition of zinc ions. In all the compounds, the peak observed before the addition decreased, and a new absorption peak was observed on the longer wavelength side. This suggests that a new structure was formed by zinc coordination.

Next, the change of the fluorescence spectrum when Zn ²⁺ was added to each compound was measured. The results are shown in FIG. In addition, (lambda) _em shown in the table _| surface below is a fluorescence peak after adding the molar amount of a zinc ion 2 times with respect to a compound. As shown in the figure, the result shows that the fluorescence peak shifts with increasing amount of added zinc ions, and the fluorescence color is greatly different. In compounds 3 and 4, a red shift was observed after the addition of zinc ions, but almost no fluorescence was observed. This seems to be due to the fact that the fluorescence derived from the compound and the fluorescence derived from zinc changed due to the coordinate bond.

<Example 8>
Differential Scanning Calorimetry Compound 1 and 2 were subjected to differential scanning calorimetry (DSC). The result is shown in FIG. In compound 1, a clear absorption peak was observed at 114 ° C. based on the transition from crystal to liquid crystal. Compound 2 had a glass transition point of 110 ° C.
FIG. 12 shows a photograph of the change in fluorescence when zinc ions are added to Compound 1. As zinc ions were added, the fluorescent color changed from blue to white to yellow (gradually darker).

<Example 9>
Configuration of Light-Emitting Element A hole injection layer made of Vitron P was formed by spin coating on a substrate on which ITO having a sheet resistance of 15 Ω / cm ² was formed on a glass substrate. The layer pressure of the obtained hole injection layer was 40 nm. Next, a light emitting layer composed of a conjugated oligomer a (R ₁ = C ₆ H ₁₃ , R ₂ = H, n = 1) was formed on the hole injection layer by spin coating. Spin coating was performed using a mixed solution in which a toluene solution containing 4% by weight of a conjugated oligomer and a methyl cellosolve solution of zinc acetate containing half the number of moles of the conjugated oligomer were mixed. The film thickness of the obtained light emitting layer was 70 nm.
Next, 6 nm of Ca and 250 nm of Al were vapor-deposited as a cathode on the light emitting layer, respectively, and the light emitting element was produced.
When the light emission characteristics of the light emitting element were examined, the luminance at a current density of 10 mA / cm ² was 418 cd / m ² and the driving voltage was 3.85 V. In addition, the luminance half life in constant current driving at a current density of 10 mA / cm ² was 500 hours.

<Example 10>
A light emitting device was fabricated in the same manner as in Example 9 except that the conjugated oligomer b (R ₁ = C ₆ H ₁₃ , n = 1) was used for the light emitting layer. The luminance of the light emitting element at a current density of 10 mA / cm ² was 18 cd / m ² and the driving voltage was 5.5V. The luminance half life in constant current driving at a current density of 10 mA / cm ² was 20 hours.

<Example 11>
A light emitting device was produced in the same manner as in Example 9 except that the conjugated oligomer c (R ₁ = C ₆ H ₁₃ , n = 2) was used for the light emitting layer. The luminance of the light emitting element at a current density of 10 mA / cm ² was 200 cd / m ² and the driving voltage was 4.5V. The luminance half life in constant current driving at a current density of 10 mA / cm ² was 20 hours.

<Example 12>
As the light emitting layer, the conjugated oligomer a of Example 9 was used in place of metal ions instead of ruthenium chloride, and a light emitting device was produced in the same manner. The luminance of the light emitting element at a current density of 10 mA / cm ² was 700 cd / m ² and the driving voltage was 4.2V. The luminance half life in constant current driving at a current density of 10 mA / cm ² was 800 hours.
As a result, the luminescent color changed to orange by changing the metal ion species from zinc to ruthenium. It was confirmed that the conjugated oligomer having a ligand is a light emitting material capable of changing the emission color depending on the metal ion species to be added.

It is a schematic sectional drawing which shows one Embodiment of the light emitting element of this invention. It is a schematic sectional drawing which shows other embodiment of the light emitting element of this invention. It is a visible absorption-spectrum measurement result in the dichloromethane of the compounds 1-4 of this invention. It is a fluorescence-spectrum measurement result in the dichloromethane of the compounds 1-4 of this invention. It is a measurement result of the visible absorption spectrum in a dichloromethane at the time of adding an iron ion to the compounds 1-2 of this invention. It is a measurement result of the visible absorption spectrum in a dichloromethane at the time of adding an iron ion to the compounds 3-4 of this invention. It is a measurement result of the fluorescence spectrum in a dichloromethane at the time of adding an iron ion to the compounds 1-4 of this invention. It is a measurement result of the visible absorption spectrum in a dichloromethane at the time of adding a zinc ion to the compounds 1-4 of this invention. It is a measurement result of the visible absorption spectrum in a dichloromethane at the time of adding a zinc ion to the compounds 1-4 of this invention. It is a measurement result of the fluorescence spectrum in a dichloromethane at the time of adding a zinc ion to the compounds 1-4 of this invention. It is a differential scanning calorimetry result of the compounds 1 and 2 of this invention. It is a photograph which shows the change of fluorescence coloring light at the time of adding a zinc ion to the compound 1 of this invention.

Claims (9)

  It consists of a coordination compound obtained by coordinating a metal ion species with a bridging ligand formed by linking a ligand to both sides of a conjugated oligomer having a fluorescent core, and the luminescent color of the bridging ligand An organic electroluminescent material which emits light having a different emission color from the above. The bridging ligand has the following basic structure:
L ₁ -B ₁ -AB ₂ -L ₂
[In the above formula,
L ₁ and L ₂ may be the same or different from each other,

Represents a ligand selected from the group consisting of
・ A is

(In the above formula, Ra and Rb represent an alkyl group which may be the same or different from each other) and represent a fluorene core having a fluorescent color development,
B ₁ and B ₂ may be the same or different from each other,

(In the above formula, Rc and Rd may be the same or different from each other, and represent hydrogen, an alkyl group or an alkoxy group, and n represents an integer of 1 to 3)
Represents an oligomer selected from the group consisting of]
The organic electroluminescent material according to claim 1, comprising:   The organic electroluminescent material according to claim 1 or 2, wherein the metal ion species is selected from the group consisting of zinc, aluminum, ruthenium, osmium, terbium, europium, platinum, gold, and iridium. The bridging ligand is the following compound:

4. The method according to claim ₁ , wherein R ₁ is an alkyl group, R ₂ is hydrogen, an alkyl group or an alkoxy group, and n is an integer of 1 to 3. The organic electroluminescent material described in 1.   The organic electroluminescent material according to any one of claims 1 to 4, wherein the metal ion species is present at a molar concentration of not more than twice the concentration of the conjugated oligomer.   The light emitting layer according to any one of claims 1 to 5, wherein a hole injection layer and a light emitting layer are disposed between the anode and the cathode, and a voltage is applied between the anode and the cathode to cause electroluminescence. A light emitting element formed from an organic electroluminescent material.   In a method of manufacturing a light emitting device in which a hole injection layer and a light emitting layer are disposed between an anode and a cathode and a voltage is applied between the anode and the cathode to cause electroluminescence, a core that emits fluorescence is formed on the hole injection layer. A method comprising forming a light emitting layer by applying a solution containing a cross-linked ligand obtained by linking a ligand to both sides of a conjugated oligomer and a metal ion species. The bridging ligand has the following basic structure:
L ₁ -B ₁ -AB ₂ -L ₂
[In the above formula,
L ₁ and L ₂ may be the same or different from each other,

Represents a ligand selected from the group consisting of
・ A is

(In the above formula, Ra and Rb represent an alkyl group which may be the same or different from each other) and represent a fluorene core having a fluorescent color development,
B ₁ and B ₂ may be the same or different from each other,

(In the above formula, Rc and Rd may be the same or different from each other, and represent hydrogen, an alkyl group or an alkoxy group, and n represents an integer of 1 to 3)
Represents an oligomer selected from the group consisting of]
The method of claim 7, wherein the metal ion species is selected from the group consisting of zinc, aluminum, ruthenium, osmium, terbium, europium, platinum, gold, iridium.   The method according to claim 7 or 8, wherein the concentration of the metal ion species is not more than twice the molar concentration of the bridging ligand in the solution.

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