METAL COMPLEX AND APPLICATION THEREOF

Abstract

The present invention relates to a metal complex having a structure of chemical formula (I). The metal complex is applied to an organic light-emitting device which emits deep red or near-infrared light, and shows a lower driving voltage and higher luminous efficiency, and has greatly prolonged service life. Therefore, the metal complex has the potential of being applied in the field of organic light-emitting devices. Also provided is an organic light-emitting device, including a cathode, an anode, and an organic layer. The organic layer is one or more of a hole injection layer, a hole transport layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer; and at least one layer in the organic layer contains the compound of structural formula (I).

##STR00001##

Claims

1. A metal complex, being a compound having a structure as shown in Formula (I): ##STR00037## wherein: R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, R.sup.9, R.sup.10, R.sup.11, R.sup.12, and R.sup.13 are each independently selected from: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1-20 carbon atoms, substituted or unsubstituted cycloalkyl having 3-20 carbon atoms, substituted or unsubstituted alkoxy having 1-20 carbon atoms, substituted or unsubstituted aryl having 6-30 carbon atoms, and substituted or unsubstituted heteroaryl having 3-30 carbon atoms or cyano; Ar.sup.1 is a heteroaromatic group containing at least two N atoms and 3-30 carbon atoms; Ar.sup.2 and Ar.sup.3 are each independently selected from an aromatic group or a heteroaromatic group having 3-30 carbon atoms; heteroatom in the heteroaromatic group is selected from atoms N, S, O; and wherein the substitution refers to a substitution by deuterium, halogen or alkyl having 1-8 carbon atoms.

2. The metal complex according to claim 1, wherein in the Formula (I), R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, R.sup.9, R.sup.10, R.sup.11, R.sup.12, and R.sup.13 are respectively selected from: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1-6 carbon atoms, substituted or unsubstituted cycloalkyl having 3-6 carbon atoms, substituted or unsubstituted alkoxy having 1-6 carbon atoms, substituted or unsubstituted aryl having 6-12 carbon atoms, and substituted or unsubstituted heteroaryl having 3-12 carbon atoms or cyano; Ar.sup.1 is a heteroaromatic group containing 2-4 heteroatoms and 3-12 carbon atoms; Ar.sup.2 and Ar.sup.3 are each independently selected from an aromatic group or a heteroaromatic group having 3-12 carbon atoms; heteroatom in the heteroaromatic group is selected from atoms N, S, O; and wherein the substitution refers to a substitution by deuterium or alkyl having 1-4 carbon atoms.

3. The metal complex according to claim 2, wherein in the Formula (I), R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, R.sup.9, R.sup.10, R.sup.11, R.sup.12, and R.sup.13 are respectively selected from: hydrogen, deuterium, substituted or unsubstituted alkyl having 1-4 carbon atoms, substituted or unsubstituted cycloalkyl having 3-6 carbon atoms; Ar.sup.2 and Ar.sup.3 are each independently selected from an aromatic group or a heteroaromatic group having 5-10 carbon atoms.

4. The metal complex according to claim 3, wherein the Ar.sup.1 is selected from the following aromatic structures. ##STR00038## ##STR00039##

5. The metal complex according to claim 4, wherein the Ar.sup.1 is selected from the following aromatic structures: ##STR00040##

6. The metal complex according to any one of claims 1-5, wherein Ar.sup.2 and Ar.sup.3 are the same aromatic group.

7. The metal complex according to claim 6, wherein the Ar.sup.2 and the Ar.sup.3 are selected from a benzene or naphthalene unit group.

8. The metal complex according to claim 7, wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, R.sup.9 and R.sup.10 are hydrogen; the Ar.sup.2 and the Ar.sup.3 are benzene.

9. The metal complex according to claim 1, having one of the following structural formulas: ##STR00041## ##STR00042## ##STR00043## ##STR00044## ##STR00045## ##STR00046## ##STR00047## ##STR00048## ##STR00049## ##STR00050## ##STR00051## ##STR00052## ##STR00053## ##STR00054## ##STR00055## ##STR00056## ##STR00057## ##STR00058## ##STR00059## ##STR00060## ##STR00061## ##STR00062## ##STR00063##

10. A precursor of the metal complex according to any one of claims 1-9, namely, a ligand, having the following structural formula: ##STR00064##

11. An application of the metal complex of any one of claims 1-9 in an organic optoelectronic device, wherein the organic optoelectronic device comprises an organic light-emitting device, an organic thin film transistor, an organic photovoltaic device, a luminescent electrochemical cell and a chemical sensor.

12. An organic light-emitting device, comprising a cathode, an anode, and an organic layer, wherein the organic layer is one or more of a hole injection layer, a hole transport layer, a light-emitting layer, a hole blocking layer, an electron injection layer and an electron transport layer; and the organic layer comprises the metal complex of any one of claims 1-9.

13. The organic light-emitting device according to claim 12, wherein the metal complex of any one of claims 1-9 is located at the light-emitting layer and the electron transport layer.

14. The organic light-emitting device according to claim 12, wherein the organic layer has a total thickness of 1-1000 nm; and the organic layer forms a thin film via evaporation or a solution method.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0031] FIG. 1 is a structure diagram showing an organic light-emitting device of the present invention;

[0032] 10 represents glass substrate; 20 represents anode; 30 represents hole injection layer; 40 represents hole transport layer; 50 represents light-emitting layer; 60 represents hole blocking layer; 70 represents electron transport layer; 80 represents electron injection layer; 90 represents cathode.

DETAILED DESCRIPTION OF EMBODIMENTS

[0033] The synthesis method of the material is not required in this present invention. To describe the present invention specifically, examples are set forth below, but not limited thereto.

[0034] Raw materials of the compound of the following formula are commercially available.

Example 1

[0035] Synthesis of the Complex 4

##STR00030## ##STR00031##

[0036] Synthesis of the Intermediate 4c

[0037] The compound 4a (3.5 g, 19.2 mmol), compound 4b (4.6 g, 23.0 mmol), palladium acetate (0.4 g, 0.2 mmol) and CsF (3.0 g, 20.0 mmol) were dissolved into a mixed solution of trifluoromethanesulfonic acid (10 mL) and water (30 mL), and heated up to 60° C. for reaction for 8 h. The above reaction liquid was cooled to room temperature and added to water, then extracted for three times with dichloromethane; organic phases were combined. The organic phase was dried by anhydrous sodium sulfate and subjected to rotary evaporation to remove solvent; the residue was separated by column chromatography to obtain a white solid (4.7 g, yield: 71%). ESI-MS (m/z): 339.9 (M+1). Remarks: the reaction yield reduces significantly when the reaction is amplified.

[0038] Synthesis of the Compound 4e

[0039] The compound 4c (17.0 g, 50.0 mmol) was dissolved into tetrahydrofuran (100 mL) under the protection of nitrogen, and cooled to −78° C., then dropwisely added with n-butyllithium BuLi (1.2 eq), and stirred for 30 min, afterwards, the tetrahydrofuran solution (30 mL) of the compound 4d (17.3 g, 50.0 mmol) was dropwisely added to the above solution, stirred for 30 min, and heated up to room temperature, and stirred for 1 h continuously. The above reaction liquid was added to water and then extracted for three times with dichloromethane; organic phases were combined. The organic phase was dried by anhydrous sodium sulfate and subjected to rotary evaporation to remove solvent, thus obtaining a light yellow solid. The above solid was dissolved into acetic acid (50 mL), and added with concentrated sulfuric acid (4 mL) for reflux over the night under the protection of nitrogen. The above reaction liquid was cooled to room temperature and added to water, then extracted for three times with dichloromethane; organic phases were combined. The organic phase was dried by anhydrous sodium sulfate and subjected to rotary evaporation to remove solvent; the residue was separated by column chromatography to obtain a light yellow solid (18.6 g, yield: 63%). ESI-MS (m/z): 588.1 (M+1).

[0040] Synthesis of the Compound 4f

[0041] The compound 4e (5.9 g, 10.0 mmol), o-hydroxybenzeneboronic acid (1.6 g, 12.0 mmol), Pd(PPh.sub.3).sub.4 (0.6 g, 0.5 mmol), K.sub.2CO.sub.3 (4.0 g, 30.0 mmol), tetrahydrofuran (50 mL) and water (5 mL) were successively added to a Schlenk tube under the protection of nitrogen. The system was heated up to 80° C. for reaction for 24 h. The above reaction liquid was cooled to room temperature and added to water, then extracted for three times with dichloromethane; organic phases were combined. The organic phase was dried by anhydrous sodium sulfate and subjected to rotary evaporation to remove solvent; the residue was separated by column chromatography to obtain an off white solid (4.9 g, yield: 81%). ESI-MS (m/z): 600.2 (M−1).

[0042] Synthesis of the Compound 4g

[0043] The compound 4f (4.9 g, 8.1 mmol), bis(pinacolato)diboron (37 mmol, 10.0 mmol), potassium acetate (2.5 g, 25.0 mmol), and Pd(dppf)Cl.sub.2 (0.3 g, 0.4 mmol) were dissolved into dioxane (50 mL) under the protection of nitrogen, and replaced by nitrogen for several times, then heated for reflux reaction over the night. The above reaction liquid was cooled to room temperature and added to water, then extracted for three times with ethyl acetate; organic phases were combined. The organic phase was dried by anhydrous sodium sulfate and subjected to rotary evaporation to remove solvent; the residue was separated by column chromatography to obtain an off white solid (4.5 g, yield: 85%). ESI-MS (m/z): 648.4 (M−1).

[0044] Synthesis of the Compound 4h

[0045] The compound 4g (4.2 g, 6.5 mmol), chloro-s-triazine (1.0 g, 8.5 mmol), Pd(PPh.sub.3).sub.4 (0.3 g, 0.3 mmol), K.sub.2CO.sub.3 (1.3 g, 10.0 mmol), tetrahydrofuran (30 mL) and water (5 mL) were successively added to a Schlenk tube under the protection of nitrogen. The system was heated up to 80° C. for reaction for 24 h. The above reaction liquid was cooled to room temperature and added to water, then extracted for three times with dichloromethane; organic phases were combined. The organic phase was dried by anhydrous sodium sulfate and subjected to rotary evaporation to remove solvent; the residue was separated by column chromatography to obtain a light yellow solid (2.4 g, yield: 62%). ESI-MS (m/z): 601.3 (M−1).

[0046] Synthesis of the Complex 4

[0047] The compound 4h (2.0 g, 3.3 mmol), potassium chloroplatinate (1.7 g, 4.0 mmol) and 250 mL acetic acid were added to a flask and stirred for 48 h at reflux under the protection of nitrogen. The above reaction liquid was cooled to room temperature, then added to water and filtered to obtain a coarse product, and the coarse product was recrystallized to obtain a red solid (2.4 g, yield: 90%). ESI-MS (m/z): 796.3 (M+1).

Example 2

[0048] Synthesis of the Complex 29

##STR00032##

[0049] Synthesis of the Compound 29b

[0050] The intermediate chloro-s-triazine was replaced with an intermediate 29a and the compound 29b was prepared by reference to the synthesis method of the compound 4h to obtain a light yellow solid (3.2 g, yield: 70%) ESI-MS (m/z): 650.3 (M−1).

[0051] Synthesis of the Complex 29

[0052] The intermediate 4h was replaced with an intermediate 29b and the compound complex 29 was prepared by reference to the synthesis method of the complex 4 to obtain a red solid (2.9 g, yield: 85%) ESI-MS (m/z): 845.3 (M+1).

Example 3

[0053] Synthesis of the Complex 32

##STR00033##

[0054] Synthesis of the Compound 32b

[0055] The intermediate chloro-s-triazine was replaced with an intermediate 32a and the compound 32b was prepared by reference to the synthesis method of the compound 4h to obtain a light yellow solid (2.1 g, yield: 55%) ESI-MS (m/z): 639.3 (M−1).

[0056] Synthesis of the Complex 32

[0057] The intermediate 4h was replaced with an intermediate 32b and the compound complex 32 was prepared by reference to the synthesis method of the complex 4 to obtain a red solid (2.3 g, yield: 81%) ESI-MS (m/z): 834.3 (M+1).

Example 4

[0058] Synthesis of the Complex 36

##STR00034##

[0059] Synthesis of the Compound 36b

[0060] The intermediate chloro-s-triazine was replaced with an intermediate 32a and the compound 32b was prepared by reference to the synthesis method of the compound 4h to obtain a light yellow solid (2.1 g, yield: 55%)ESI-MS (m/z): 700.3 (M−1).

[0061] Synthesis of the Complex 36

[0062] The intermediate 4h was replaced with an intermediate 36b and the compound complex 36 was prepared by reference to the synthesis method of the complex 4 to obtain a red solid (1.9 g, yield: 65%)ESI-MS (m/z): 895.5 (M+1).

Example 5

[0063] Synthesis of the Complex 54

##STR00035##

[0064] Synthesis of the Compound 54b

[0065] The intermediate chloro-s-triazine was replaced with an intermediate 54a and the compound 54b was prepared by reference to the synthesis method of the compound 4h to obtain a light yellow solid (3.5 g, yield: 69%)ESI-MS (m/z): 664.4 (M−1).

[0066] Synthesis of the Complex 54

[0067] The intermediate 4h was replaced with an intermediate 54b and the compound complex 54 was prepared by reference to the synthesis method of the complex 4 to obtain a red solid (1.3 g, yield: 81%)ESI-MS (m/z): 859.2 (M+1).

Examples 6-10

[0068] A light-emitting device was prepared by using the complex light-emitting material of the present invention, and the device has a structure shown in FIG. 1.

[0069] Firstly, a transparent conductive ITO glass substrate 10 (an anode 20 was provided) was successively cleaned with a detergent solution and deionized water, ethanol, acetone, and deionized water, and then subjected to plasma treatment with oxygen for 30 s.

[0070] HATCN having a thickness of 10 nm was then evaporated on the ITO as a hole injection layer 30.

[0071] A compound NPB was then evaporated to form a hole transport layer 40 having a thickness of 40 nm.

[0072] A light-emitting layer 50 having a thickness of 20 nm was then evaporated on the hole transport layer; the light-emitting layer was obtained by mixing and doping the complex 4 (Example 6) in Examples 1-5, complex 29 (Example 7), complex 32 (Example 8), complex 36 (Example 9), or complex 54 (Example 10) with CBP (95%) respectively.

[0073] Alq having a thickness of 10 nm was then evaporated on the light-emitting layer as a hole blocking layer 60,

[0074] then, Alq.sub.3 having a thickness of 40 nm was evaporated on the hole blocking layer as an electron transport layer 70.

[0075] Finally, 1 nm LiF was evaporated as an electron injection layer 80 and 100 nm Al was evaporated as a cathode 90 of the device.

Comparative Example

[0076] The compound of the present invention was replaced with (pq).sub.2Ir(acac) to prepare the organic light-emitting device according to the same method.

[0077] HATCN, NPB, CBP, (pq).sub.2Ir(acac), Alq.sub.3 and BAlq in the device have the following structural formulas:

##STR00036##

[0078] Performance of the organic electroluminescent devices in Examples 6-10 and Comparative Example at an electric current density of 10 mA/cm.sup.2 is listed in Table 1:

TABLE-US-00001 TABLE 1 Device service Driving Luminous life Emitting Example Compound voltage efficiency (LT90) color 6 4 0.83 1.6 2.1 Dark red light 7 29 0.83 1.3 2.0 Dark red light 8 32 0.91 1.2 1.5 Dark red light 9 36 0.76 1.3 2.1 Near- infrared light 10 54 0.82 1.4 1.6 Dark red light Comparative (pq).sub.2Ir(acac) 1 1 1 Red light Example Remarks: the performance test of the device is by reference to the Comparative Example; each index in the Comparative Example is set 1; LT90 shows the corresponding time when the device brightness attenuates to 90% of the initial brightness.

[0079] It can be seen from the data of Table 1 that under the same conditions, the efficiency of the organic light-emitting device prepared by the compound of the present invention is superior to that of the Comparative Example; compared with a common red emitting material (pq).sub.2Ir(acac), the metal complex material of the present invention is applied in an organic light-emitting device to have a lower driving voltage and greatly improved service life, and to emit dark red or near-infrared light, which conforms to the demands of the display industry for light-emitting materials and thus, has good industrialization prospect.

Example 11

[0080] Ratio (Φ.sub.PPMA/Φ.sub.solution) of luminescence quantum yields of the metal complexes 4, 29, 32, 36 and 54 in the PMMA film and dichloromethane solution is listed in Table 2:

TABLE-US-00002 TABLE 2 Complex 4 29 32 36 54 ΦP.sub.MMA/Φ.sub.solution 1.2 1.3 1.6 1.8 1.9 Φ.sub.PMMA: the luminescence quantum yield of the complex doped in PMMA(20%); Φ.sub.solution: the luminescence quantum yield of the complex doped in dichloromethane solution (1 × 10.sup.−5M).

[0081] It can be seen from the data of Table 2 that the quantum yield of the metal complex of the present invention in the state of aggregation is higher than that in solution. Due to the concentration quenching effect, the luminescence quantum yield of the platinum complex material is usually lower under the state of aggregation. The metal complex of the present invention shows the property of aggregation-induced emission enhancement. As can be seen, the present invention achieves unexpected technical effect.

[0082] The above multiple embodiments are merely set as examples, but are not construed as limiting the protection scope of the present invention. Multiple materials and structures of the present invention may be replaced by other materials and structures in the premise of not departing from the spirit of the present invention. It should be understood that a person skilled in the art can make lots of modifications and changes according to the idea of the present invention without inventive efforts. Therefore, any technical solution obtained by a person skilled in the art on the basis of the prior art and through analysis, reasoning or partial researches shall fall within the protection scope defined in the claims.