阅读说明：本技术 一种有机金属铱配合物和其制备方法及电致发光器件 (Organic metal iridium complex, preparation method thereof and electroluminescent device ) 是由 王辉 谢星冰 李建行 刘志远 王猛 李猛 马晓宇 于 2019-11-15 设计创作，主要内容包括：本发明涉及一种有机金属铱配合物和其制备方法及电致发光器件,属于有机光电材料领域。本发明的有机金属铱配合物的结构式如化学式1所示：<Image he="548" wi="700" file="DDA0002274474390000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>其中,R<Sub>1</Sub>、R<Sub>2</Sub>、R<Sub>3</Sub>、R<Sub>4</Sub>、R<Sub>5</Sub>各自独立地选自氢、氘、卤素、氰基、取代或非取代的烷基、取代或非取代的烷氧基、取代或非取代的芳基、取代或非取代的芳族杂环基、取代或非取代的的稠环基、或取代或非取代的螺环。本发明提供的新型结构的有机金属铱配合物,通过选择特定的杂环的配体结合,调节化合物的波长,得到的有机金属化合物在用于有机电致发光器件后,使得器件的发光效率以及亮度提高。本发明提供的有机金属铱配合物的制备方法,制备步骤简单,产物纯度高。(The invention relates to an organic metal iridium complex, a preparation method thereof and an electroluminescent device, belonging to the field of organic photoelectric materials. The structural formula of the organometallic iridium complex of the invention is shown in chemical formula 1: wherein R is 1 、R 2 、R 3 、R 4 、R 5 Each independently selected from hydrogen, deuterium, halogen, cyano, substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryl, substituted or unsubstituted aromatic heterocyclic group, substituted or unsubstituted condensed ring group, or substituted or unsubstituted condensed ring groupOr an unsubstituted spirocyclic ring. The organometallic iridium complex with a novel structure provided by the invention selects the ligand combination of a specific heterocycle to adjust the wavelength of the compound, and the obtained organometallic compound is used for an organic electroluminescent device, so that the luminous efficiency and the brightness of the device are improved. The preparation method of the organic metal iridium complex provided by the invention has the advantages of simple preparation steps and high product purity.)

1. An organometallic iridium complex, characterized in that its structural formula is shown in chemical formula 1:

wherein R is₁、R₂、R₃、R₄、R₅Each independently selected from hydrogen, deuterium, halogen, cyano, substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryl, substituted or unsubstituted aromatic heterocyclic group, substituted or unsubstituted fused ring group, or substituted or unsubstituted spiro ring;

R₂the number of substituents is 0 to 1, R₁、R₃The number of the substituents is 0-4.

2. The organometallic iridium complex according to claim 1, wherein R is₁、R₂、R₃、R₄、R₅Each independently selected from substituted or unsubstituted C1-C8 alkyl, substituted or unsubstituted C1-C8 alkoxy, substituted or unsubstituted C6-C18 aryl, substituted or unsubstituted C4-C12 aromatic heterocyclic group, substituted or unsubstituted C10-C18 condensed ring group, or substituted or unsubstituted C5-C15 spiro ring.

3. The organometallic iridium complex according to claim 1, wherein R is₁、R₂、R₃Independently form a substituted or unsubstituted C3-C30 aliphatic ring, a substituted or unsubstituted C6-C18 aromatic ring, a substituted or unsubstituted C4-C18 aromatic heterocycle, a substituted or unsubstituted C10-C18 condensed ring or a substituted or unsubstituted C5-C18 spiro ring with other substituents on the ring; the substituent on the substituent group is at least one or more selected from hydrogen, deuterium, nitro, amino, hydroxyl, halogen, cyano, carbonyl and sulfydryl.

4. The organometallic iridium complex according to claim 1, wherein R is₁、R₂、R₃Respectively forms a substituted or unsubstituted C3-C30 aliphatic ring, a substituted or unsubstituted C6-C60 aromatic ring, a substituted or unsubstituted C2-C60 aromatic heterocycle, a substituted or unsubstituted C6-C60 condensed ring or a substituted or unsubstituted C5-C60 spiro ring with the substituent on the adjacent ring; front sideThe substituent on the substituent group is at least one or more selected from hydrogen, deuterium, nitro, amino, hydroxyl, halogen, cyano, carbonyl and sulfydryl.

5. The organometallic iridium complex according to claim 1, characterized in that it is selected from any one of the following structures:

6. the organometallic iridium complex according to claim 1, characterized in that it is selected from any one of the following structures:

7. a method for producing an organometallic iridium complex according to any one of claims 1 to 6, characterized by comprising the steps of:

step 1, dissolving a raw material A and iridium trichloride into a mixed solvent of ethylene glycol ethyl ether/water, and fully reacting to obtain a bridging ligand intermediate B;

step 2, adding ethylene glycol ethyl ether and potassium carbonate into the intermediate B and the intermediate C, and fully reacting to obtain an iridium metal complex shown in a chemical formula 1;

the synthetic route is as follows:

8. an organic electroluminescent device comprising the organometallic iridium complex according to any one of claims 1 to 6.

9. The organic electroluminescent device according to claim 8, comprising a light-emitting layer containing the organometallic iridium complex according to any one of claims 1 to 6.

Technical Field

The invention relates to the field of organic photoelectric materials, in particular to an organic metal iridium complex, a preparation method thereof and an electroluminescent device.

Background

The organic electroluminescence technology is a latest generation display technology, and a light-emitting device prepared from an organic light-emitting material has the advantages of light weight, thinness, flexibility and the like in appearance, and particularly can be prepared into a flexible device which cannot be compared with other light-emitting materials. In the past decade, this technology has achieved some success on the way to commercialization, for example, organic electroluminescent diodes (OLEDs) have been applied to advanced displays for smart phones, televisions and digital cameras. Organic electroluminescent materials are the core and foundation of electroluminescent devices. The development of new materials is a source for promoting the continuous progress of the electroluminescent technology. The preparation of the original material and the optimization of the device are also the research hotspots of the organic electroluminescent industry at present.

Conventional OLEDs can be classified into fluorescent and phosphorescent types. Compared with fluorescent OLEDs (theoretical luminous efficiency is 25% at the highest), phosphorescent OLEDs (theoretical luminous efficiency 100%) are the mainstream direction for OLED technology research and development due to their higher luminous efficiency. However, the phosphorescent material still needs to be further improved in the aspects of reducing the cost of the material preparation process, improving the basic photoelectric properties of the material, improving the overall tolerance and weather resistance of the material after device integration, and the like.

Disclosure of Invention

The invention aims to solve the technical problems in the prior art and provides an organic metal iridium complex, a preparation method thereof and an electroluminescent device. The organometallic iridium complex with a novel structure provided by the invention selects the ligand combination of a specific heterocycle to adjust the wavelength of the compound, and the obtained organometallic compound is used for an organic electroluminescent device, so that the driving voltage of the device is reduced, and the current efficiency and the power efficiency are improved.

In order to solve the technical problems, the technical scheme of the invention is as follows:

the invention provides an organic metal iridium complex, which has a structural formula shown as a chemical formula 1:

wherein R is₁、R₂、R₃、R₄、R₅Each independently selected from hydrogen, deuterium, halogen, cyano, substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryl, substituted or unsubstituted aromatic heterocyclic group, substituted or unsubstituted fused ring group, or substituted or unsubstituted spiro ring;

R₂the number of substituents is 0 to 1, R₁、R₃The number of the substituents is 0-4.

In the above technical solutions, R is preferable₁、R₂、R₃、R₄、R₅Each independently selected from substituted or unsubstituted C1-C8 alkyl, substituted or unsubstituted C1-C8 alkoxy, substituted or unsubstituted C6-C18 aryl, substituted or unsubstituted C4-C12 aromatic heterocyclic group, substituted or unsubstituted C10-C18 condensed ring group, or substituted or unsubstituted C5-C15 spiro ring.

The alkyl is a straight-chain alkyl, a branched-chain alkyl, a cyclic alkyl, a straight-chain alkyl substituted by at least 1 substituent, a branched-chain alkyl substituted by at least 1 substituent or a cyclic alkyl substituted by at least 1 substituent; wherein, the substituent is one or more of halogen, deuterium, cyano, hydroxyl and sulfydryl independently.

The aryl group in the invention is an unsubstituted aryl group or an aryl group substituted with at least 1 substituent; wherein, the substituent is one or more of deuterium, nitro, amino, hydroxyl, halogen, cyano, carbonyl and mercapto independently.

The aromatic heterocyclic group in the present invention is preferably an unsubstituted aromatic heterocyclic group or an aromatic heterocyclic group substituted with at least 1 substituent; wherein the heteroatom is N, O or S; the substituents on the aromatic heterocyclic group are independently one or more selected from halogen, deuterium, amino, cyano, nitro, hydroxyl and sulfydryl.

In the above technical solutions, R is preferable₁、R₂、R₃Independently form a substituted or unsubstituted C3-C30 aliphatic ring, a substituted or unsubstituted C6-C18 aromatic ring, a substituted or unsubstituted C4-C18 aromatic heterocycle, a substituted or unsubstituted C10-C18 condensed ring or a substituted or unsubstituted C5-C18 spiro ring with other substituents on the ring; the substituent on the substituent group is at least one or more selected from hydrogen, deuterium, nitro, amino, hydroxyl, halogen, cyano, carbonyl and sulfydryl.

In the above technical solutions, R is preferable₁、R₂、R₃Respectively forms a substituted or unsubstituted C3-C30 aliphatic ring, a substituted or unsubstituted C6-C60 aromatic ring, a substituted or unsubstituted C2-C60 aromatic heterocycle, a substituted or unsubstituted C6-C60 condensed ring or a substituted or unsubstituted C5-C60 spiro ring with the substituent on the adjacent ring; the substituent on the substituent group is at least one or more selected from hydrogen, deuterium, nitro, amino, hydroxyl, halogen, cyano, carbonyl and sulfydryl.

In the above technical solution, it is preferable that the organometallic iridium complex is selected from any one of the following structures:

substituent R in the chemical formulas F-1 and F-2₁～R₅And the number thereof is the same as that described for the substituent in chemical formula 1, and thus, the description thereof will be omitted.

In the above technical solution, it is most preferable that the organometallic iridium complex is selected from any one of the following structures:

some specific structural forms are listed above, but the series of compounds are not limited to the above molecular structures, and other specific molecular structures can be obtained through simple transformation of the groups and the substituted groups and substituted positions thereof, which is not described in detail herein.

The invention also provides a preparation method of the organic metal iridium complex, which comprises the following steps:

step 1, dissolving a raw material A and iridium trichloride into a mixed solvent of ethylene glycol ethyl ether/water, and fully reacting to obtain a bridging ligand intermediate B;

step 2, adding ethylene glycol ethyl ether and potassium carbonate into the intermediate B and the intermediate C, and fully reacting to obtain an iridium metal complex shown in a chemical formula 1;

the synthetic route is as follows:

wherein R is₁、R₂、R₃、R₄、R₅The substituents and their respective numbers are in accordance with the ranges defined in chemical formula 1 and are not described herein.

The present invention also provides an organic electroluminescent device comprising the organometallic iridium complex represented by chemical formula 1 of the present invention.

The organic electroluminescent device includes:

a first electrode, a second electrode and an organic layer disposed between the two electrodes, wherein the organic layer contains an organometallic iridium complex represented by chemical formula 1 of the present invention; the organometallic iridium complex represented by chemical formula 1 of the present invention may be present in the organic layer in a single form or mixed with other substances.

The organic layer at least comprises one or more of a hole injection layer, a hole transport layer, a layer with hole injection and hole transport functions, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer and a layer with electron transport and electron injection functions.

The organic electroluminescent device comprises at least one functional layer containing the organometallic iridium complex represented by chemical formula 1 of the present invention.

The organic electroluminescent device comprises a light-emitting layer containing the organometallic iridium complex represented by chemical formula 1 of the present invention. Preferably, the light emitting layer of the organic electroluminescent device includes a host material and a dopant material, and the dopant material is an iridium metal complex represented by chemical formula 1 of the present invention. Further preferably, the mixing ratio of the host material and the doping material of the light-emitting layer is 90: 10-99.5: 0.5.

The device of the invention can be used for an organic light-emitting device, an organic solar cell, electronic paper, an organic photoreceptor or an organic thin film transistor.

The invention has the beneficial effects that:

the organometallic iridium complex with a novel structure provided by the invention selects the ligand combination of a specific heterocycle to adjust the wavelength of the compound, and the obtained organometallic compound is used for an organic electroluminescent device, so that the luminous efficiency and the brightness of the device are improved.

The preparation method of the organic metal iridium complex provided by the invention has the advantages of simple preparation steps and high product purity.

Detailed Description

To further illustrate the process of the present invention, the following examples are set forth in more detail.