Triazine-containing heterocyclic compound, organic electroluminescent device and display device

Abstract

The invention provides a triazine-containing heterocyclic compound, an organic electroluminescent device and a display device, and relates to the technical field of organic photoelectricity. The triazine-containing heterocyclic compound provided by the invention can improve the electron transmission capability of a device and reduce the electron injection transmission barrier, can be used for preparing an organic electroluminescent device, and particularly can effectively reduce the driving voltage of the organic electroluminescent device and improve the current efficiency when being used as an electron transmission layer material in the organic electroluminescent device; the service life is prolonged.

Description

Technical Field

[0001] The present invention belongs to the field of organic photoelectric technology, and in particular relates to a triazine-containing heterocyclic compound, an organic electroluminescent device and a display device. Background Art

[0002] The application of organic electroluminescent (OLED) materials in fields such as information display materials and organic optoelectronic materials has great research value and promising application prospects. With the development of multimedia information technology, the performance requirements of flat-panel display devices are becoming increasingly higher. Currently, the main display technologies include plasma display devices, field emission display devices, and OLED devices. Among them, OLED devices have a series of advantages such as self-luminescence, low-voltage DC drive, full curing, wide viewing angle, and rich colors. Compared with liquid crystal display devices, OLED devices do not require a backlight, have a wider viewing angle, low power consumption, and a response speed 1000 times that of LCD devices. Therefore, OLED devices have broader application prospects.

[0003] As OLED products gradually enter the market, demand for their performance is growing. The choice of materials for the cavitation layer, light-emitting layer, and other organic functional layers significantly impacts the current efficiency, driving voltage, and lifespan of OLED devices. The search for functional layer materials with even higher performance continues. Therefore, to meet these increasing demands for OLED devices, the field urgently needs to develop a wider variety of higher-performance OLED materials. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention aims to provide a triazine-containing heterocyclic compound, an organic electroluminescent device and a display device. The triazine-containing heterocyclic compound can be used as an electron transport material for OLED devices. The resulting organic electroluminescent device has a lower driving voltage, higher current efficiency and longer life.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] In a first aspect, the present invention provides a triazine-containing heterocyclic compound, wherein the triazine-containing heterocyclic compound has a structure as shown in Formula I:

[0007]

[0008] In formula I, R1 and R2 are each independently selected from substituted or unsubstituted C6 to C 30 Aryl or substituted or unsubstituted C6~C 30 heteroaryl;

[0009] Ar1 is selected from a single bond, a substituted or unsubstituted C6 to C 30Arylene or substituted or unsubstituted C6~C 30 heteroarylene;

[0010] In R1, R2, Ar1, the substituted substituents are each independently selected from deuterium, F, cyano, trimethylsilyl, C1-C6 alkyl, C6-C 30 Aryl or C3~C 30 Heteroaryl.

[0011] Preferably, the hydrogen atoms in formula I can be replaced independently by deuterium, F, cyano, C1-C6 alkyl, C6-C 30 Aryl or C6~C 30 Heteroaryl substitution.

[0012] Preferably, the C6~C 30 Aryl is selected from phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, indenyl, fluorenyl, perylenyl, phenanthrenyl, pyrenyl, fluoranthenyl, spirofluorenyl, triphenylene, benzofluorenyl, dibenzofluorenyl, naphthacenyl, triphenylenyl.

[0013] Preferably, the C6~C 30 The arylene group is selected from phenylene, biphenylene, terphenylene, naphthylene, anthracene, indenylene, fluorenylene, perylenylene, phenanthrenylene, pyrenylene, fluoranthenylene, spirofluorenylene, triphenylene, benzofluorenylene, dibenzofluorenylene, naphthylfluorenylene, and triphenylene.

[0014] Preferably, the C1-C6 alkyl group is selected from methyl, ethyl, propyl, butyl, pentyl or hexyl.

[0015] Preferably, the C6~C 30 Heteroaryl, C3~C 30 Heteroaryl, C6~C 30 The heteroatoms in the heteroarylene group are each independently selected from O, S or N.

[0016] Preferably, the C6~C 30 The heteroaryl group is selected from carbazolyl, benzofuranyl, benzothiophenyl, dibenzofuranyl, dibenzothiophenyl, dibenzofuranophenyl or dibenzothienophenyl.

[0017] Preferably, the C3~C 30 The heteroaryl group is selected from triazinyl, carbazolyl, benzofuranyl, benzothiophenyl, dibenzofuranyl, dibenzothiophenyl, dibenzofuranophenyl or dibenzothienophenyl.

[0018] Preferably, the C6~C 30The heteroarylene group is selected from carbazolylene, benzofurylene, benzothiophenylene, dibenzofurylene, dibenzothiophenylene, dibenzofuranophenylene or dibenzothiophenophenylene.

[0019] Preferably, in Formula I, R1 and R2 are each independently selected from phenyl, biphenyl, naphthyl, phenylnaphthyl, naphthylphenyl, 9,9-dimethylfluorenyl, fluoranthenyl, triphenylene, phenanthrenyl, carbazolyl, N-phenylcarbazolyl, N-carbazolylphenyl, dibenzofuranyl or dibenzothiazolyl; more preferably, in Formula I, R1 and R2 are each independently selected from phenyl, biphenyl, naphthyl, phenylnaphthyl, 9,9-dimethylfluorenyl, carbazolyl or dibenzofuranyl.

[0020] Preferably, in Formula I, Ar1 is selected from a single bond, a phenylene group, a biphenylene group or a naphthylene group.

[0021] Preferably, the triazine-containing heterocyclic compound is selected from any one of the following compounds:

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028] Preferably, the triazine-containing heterocyclic compound is selected from any one of the following compounds 1 to 12:

[0029]

[0030] The present invention lists some specific structural forms of the triazine-containing heterocyclic compound, but the triazine-containing heterocyclic compound of the present invention is not limited to these listed chemical structures. Any structure based on the structure shown in Formula I where R1, R2, and Ar1 meet the above-mentioned limiting conditions should be included.

[0031] In a second aspect, the present invention provides an organic electroluminescent device, comprising the triazine-containing heterocyclic compound as described in the first aspect.

[0032] Preferably, the organic electroluminescent device comprises a first electrode, a second electrode and an organic layer disposed between the first electrode and the second electrode;

[0033] The organic layer includes the triazine-containing heterocyclic compound as described in the first aspect.

[0034] Preferably, the organic layer includes an electron transport layer;

[0035] The electron transport layer includes the triazine-containing heterocyclic compound as described in the first aspect.

[0036] In a third aspect, the present invention provides a display device, comprising the organic electroluminescent device.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] The triazine-containing heterocyclic compound provided by the present invention has an indene ring and a benzofuranopyridine ring fused at a specific position, has high conjugation ability, and is coordinated with the triazine group connected at the specific position and groups at other defined positions in the parent nucleus. It can increase the electron transport capacity of the device, reduce the electron injection and transport barrier, reduce the driving voltage, and thus improve the luminous efficiency of the device. It has good luminous performance and can be used to prepare organic electroluminescent devices, especially as an electron transport layer material in organic electroluminescent devices. It can effectively reduce the driving voltage of the organic electroluminescent device, improve the current efficiency, and extend the service life. DETAILED DESCRIPTION

[0039] For the convenience of understanding the present invention, the present invention is given below with examples. It should be understood by those skilled in the art that the examples are only for the purpose of helping to understand the present invention and should not be regarded as specific limitations of the present invention.

[0040] Synthesis Example 1

[0041] This embodiment provides a method for synthesizing compound 1. The synthetic route of compound 1 is as follows:

[0042]

[0043] Synthesis of intermediate 1-1

[0044] Under nitrogen protection, 20.0 mmol of raw material A, 20.0 mmol of raw material B, 300 ml of toluene, and 0.04 mol of glacial acetic acid were added to the reaction flask, and the temperature was raised to reflux and stirred for reaction for 6 h. After the reaction was completed, the temperature was lowered to room temperature and the solvent was removed by distillation under reduced pressure. The crude product was purified by silica gel column chromatography using ethyl acetate / n-heptane as eluent to obtain intermediate 1-1.

[0045] The intermediate 1-1 was detected by mass spectrometry, with an m / z of 401.14.

[0046] Synthesis of intermediate 1-2

[0047] With reference to the synthesis method disclosed in the literature: Org. Lett., 2021, 23, 9526-9532, under nitrogen protection, 30.0 mmol of intermediate 1-1 and 34.0 mmol of raw material C were dissolved in 100 mL of 1,2-dichloroethane, and 60.0 mmol of trifluoromethanesulfonic acid was added. The mixture was heated in an oil bath and the oil temperature was controlled at 80°C. The reaction was stirred for 10 hours. After the reaction was completed, the mixture was cooled to room temperature, concentrated and dried under reduced pressure, and separated and purified on a silica gel column to obtain intermediate 1-2.

[0048] The intermediate 1-2 was detected by mass spectrometry, with an m / z of 381.15.

[0049] Synthesis of intermediates 1-3

[0050] Under nitrogen protection, 30.0 mmol of intermediate 1-2, 120.0 mmol of anhydrous potassium carbonate and 90 mL of DMF were mixed, heated to 125°C, and stirred for reaction for 5 h. After the reaction was completed, the mixture was cooled to room temperature, poured into 250 mL of ice water, filtered, and the filter cake was washed with water and then recrystallized from methanol to obtain intermediate 1-3.

[0051] The intermediate 1-3 was detected by mass spectrometry, with an m / z of 361.15.

[0052] Synthesis of intermediates 1-4

[0053] Under nitrogen protection, 20.0 mmol of intermediate 1-3 was dissolved in 100 mL of dichloromethane, and then 22.0 mmol of N-bromosuccinimide was added in batches. The reaction was stirred at room temperature for 2 h. After the reaction was completed, 50 mL of water was added, the liquid was separated, and the organic phase was washed three times with water, then dried and filtered. The filtrate was concentrated under reduced pressure to dryness to obtain intermediate 1-4.

[0054] The intermediate 1-4 was detected by mass spectrometry, with m / z of 439.06.

[0055] Intermediate 1-4 was subjected to nuclear magnetic resonance detection, and the data are as follows: 1 H-NMR (Bruker, Switzerland, AvanceⅡ400MHz nuclear magnetic resonance spectrometer, CDCl3), δ8.11 (d, 1H), δ8.09 (m, 1H), 7.55 (m, 1H), δ7.53~7.39 (m, 7H), δ7.35 (d, 1H), δ7.20 (m, 1H), δ1.71 (s, 6H).

[0056] Synthesis of intermediates 1-5

[0057] Under nitrogen protection, 20.0 mmol of intermediate 1-4, 30 mmol of pinacol borate, 0.4 mmol of bistriphenylphosphine palladium dichloride, 60 mmol of potassium acetate, and 200 ml of toluene were added to the reaction flask, and the temperature was raised to reflux and stirred for 6 hours. After the reaction was completed, the temperature was cooled to room temperature, 400 ml of water was added to the reaction solution, and the mixture was stirred for 30 minutes. The liquid was separated, and the obtained organic phase was washed twice with 300 ml of water. The organic phase was then concentrated to 100 ml, 200 ml of ethanol was added, and the mixture was stirred for 30 minutes. The mixture was filtered, and the filter cake was recrystallized with a mixed solvent of toluene and ethanol to obtain intermediate 1-5.

[0058] The intermediate 1-5 was detected by mass spectrometry, with m / z of 487.23.

[0059] Synthesis of compound 1

[0060] Under nitrogen protection, 20.0 mmol of raw material D (2-chloro-4,6-diphenyl-1,3,5-triazine), 22.0 mmol of intermediate 1-5, 0.4 mmol of tetrakistriphenylphosphine palladium, 30 mmol of potassium carbonate, 300 ml of toluene, 100 ml of ethanol, and 100 ml of water were added to the reaction flask, and the temperature was raised to reflux and stirred for reaction for 12 h. After the reaction was completed, the temperature was lowered to room temperature, 400 ml of ethanol was added to the reaction solution, stirred for 30 min, and filtered. The filter cake was washed twice with 300 ml of water, filtered, and the filter cake was recrystallized with a mixed solvent of toluene and ethanol to obtain compound 1.

[0061] Compound 1 was detected by mass spectrometry, with an m / z of 592.23.

[0062] Referring to the synthesis method of compound 1 above, the compounds shown in Table 1 below were prepared. The only difference from compound 1 was that the raw material D was replaced by 2-chloro-4,6-diphenyl-1,3,5-triazine with an equimolar amount of other compounds (see Table 1). Other conditions remained unchanged:

[0063] Table 1

[0064]

[0065]

[0066]

[0067]

[0068] Other compounds for which the specific synthesis methods are not listed can be synthesized by referring to the above examples in combination with common knowledge in the art.

[0069] The specific structures of some of the materials used in the following device examples and device comparative examples are as follows:

[0070]

[0071] The device examples use the compounds of the present application as electron transport materials in the organic electroluminescent devices, and the device comparative examples use E1 to E3 as electron transport materials in the organic electroluminescent devices.

[0072] Device Example 1

[0073] The structure of the organic electroluminescent device is: ITO / HT (40 nm) / BH-1:BD-13% (30 nm) / Compound 1 (30 nm) / LiF (0.5 nm) / Al (150 nm).

[0074] The preparation method of the organic electroluminescent device is as follows:

[0075] A glass substrate coated with an ITO transparent conductive layer (serving as an anode) is ultrasonically treated in a cleaning agent, then rinsed in deionized water, ultrasonically degreased in a mixed solvent of acetone and ethanol, and baked in a clean environment until the water is completely removed. The substrate is then cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam to improve the surface properties and enhance its binding ability with the hole injection layer.

[0076] The glass substrate was placed in a vacuum chamber and evacuated to 1×10 -5 ~1×10 -6 Pa, HT was vacuum evaporated on the anode as a hole transport layer with an evaporation rate of 0.1 nm / s and a film thickness of 40 nm;

[0077] The light-emitting layer is vacuum-deposited on the hole transport layer at a deposition rate of 0.1 nm / s and a deposition film thickness of 30 nm. The main material of the light-emitting layer is BH-1, and the doping material is BD-1. 3% refers to the doping ratio of the doping material, that is, the volume ratio of the main material of the light-emitting layer to the doping material is 97:3.

[0078] Compound 1 was vacuum-evaporated onto the light-emitting layer to form an electron transport layer (ETL) at a rate of 0.1 nm / s to a thickness of 30 nm. 0.5 nm of LiF and 150 nm of Al were vacuum-evaporated onto the ETL to form the EIL and cathode. The luminance, driving voltage, current efficiency, and lifetime of the resulting organic electroluminescent device were measured.

[0079] Device Examples 2 to 12

[0080] Device Examples 2 to 12 each provide an organic electroluminescent device, which differs from Device Example 1 only in that the electron transport material is different (see Table 2 below for details), and other conditions are the same as those of Device Example 1.

[0081] Device Comparative Examples 1 to 3

[0082] Device Comparative Examples 1 to 3 respectively provide an organic electroluminescent device, which differs from Device Example 1 only in that the electron transport material is different (see Table 2 below for details), and other conditions are the same as those of Device Example 1.

[0083] Performance Testing

[0084] Test method: Test the driving voltage, current efficiency and life LT90 of the OLED devices provided above; LT90 refers to the time required for the brightness to drop to 90% of the original brightness while maintaining the current density at the initial brightness of 1000nit. The test items include the brightness, driving voltage, current efficiency and life LT90 of the organic electroluminescent device. The driving voltage, current efficiency and LT90 data are all based on a brightness of 1000cd / m 2 The relative values ​​of the device performance test results are shown in Table 2 below:

[0085] Table 2

[0086]

[0087] As can be seen from the contents of Table 2, the present invention obtains a triazine-containing heterocyclic compound through molecular design, which can be used as an electron transport material for OLED light-emitting devices, so that the OLED light-emitting devices have a lower driving voltage, higher current efficiency and longer life.

[0088] The present invention uses the above-described embodiments to illustrate the detailed process flow of the present invention. However, the present invention is not limited to the above-described detailed process flow, that is, it does not mean that the present invention must rely on the above-described detailed process flow to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent replacements of various raw materials in the products of the present invention, addition of auxiliary ingredients, and selection of specific methods, etc., are all within the scope of protection and disclosure of the present invention.

Claims

1. A triazine-containing heterocyclic compound, characterized in that: The triazine-containing heterocyclic compound has a structure as shown in Formula I: In formula I, R1 and R2 are each independently selected from substituted or unsubstituted C6 to C 30 Aryl or substituted or unsubstituted C6~C 30 heteroaryl; Ar1 is selected from a single bond, a substituted or unsubstituted C6 to C 30 Arylene or substituted or unsubstituted C6~C 30 heteroarylene; In R1, R2, Ar1, the substituted substituents are each independently selected from deuterium, F, cyano, trimethylsilyl, C1-C6 alkyl, C6-C 30 Aryl or C3~C 30 Heteroaryl.

2. The triazine-containing heterocyclic compound according to claim 1, characterized in that The hydrogen atoms in formula I can be replaced independently by deuterium, F, cyano, C1-C6 alkyl, C6-C 30 Aryl or C6~C 30 Heteroaryl substitution.

3. The triazine-containing heterocyclic compound according to claim 1 or 2, characterized in that The C6~C 30 Aryl is selected from phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, indenyl, fluorenyl, perylenyl, phenanthrenyl, pyrenyl, fluoranthenyl, spirofluorenyl, triphenylene, benzofluorenyl, dibenzofluorenyl, naphthacenyl, triphenylenyl; Preferably, the C6~C 30 Arylene is selected from phenylene, biphenylene, terphenylene, naphthylene, anthrylene, indenylene, fluorenylene, perylenylene, phenanthrenylene, pyrenylene, fluoranthenylene, spirofluorenylene, triphenylene, benzofluorenylene, dibenzofluorenylene, naphthylfluorenylene, and triphenylene; Preferably, the C1-C6 alkyl group is selected from methyl, ethyl, propyl, butyl, pentyl or hexyl.

4. The triazine-containing heterocyclic compound according to claim 1 or 2, characterized in that The C6~C 30 Heteroaryl, C3~C 30 Heteroaryl, C6~C 30 The heteroatoms in the heteroarylene group are each independently selected from O, S or N; Preferably, the C6~C 30 Heteroaryl is selected from carbazolyl, benzofuranyl, benzothiophenyl, dibenzofuranyl, dibenzothiophenyl, dibenzofuranophenyl or dibenzothienophenyl; Preferably, the C3~C 30 Heteroaryl is selected from triazinyl, carbazolyl, benzofuranyl, benzothiophenyl, dibenzofuranyl, dibenzothiophenyl, dibenzofuranophenyl or dibenzothienophenyl; Preferably, the C6~C 30 The heteroarylene group is selected from carbazolylene, benzofurylene, benzothiophenylene, dibenzofurylene, dibenzothiophenylene, dibenzofuranophenylene or dibenzothiophenophenylene.

5. The triazine-containing heterocyclic compound according to claim 1 or 2, characterized in that In Formula I, R1 and R2 are each independently selected from phenyl, biphenyl, naphthyl, phenylnaphthyl, naphthylphenyl, 9,9-dimethylfluorenyl, fluoranthenyl, triphenylene, phenanthrenyl, carbazolyl, N-phenylcarbazolyl, N-carbazolylphenyl, dibenzofuranyl or dibenzothiazolyl; Preferably, Ar1 is selected from a single bond, a phenylene group, a biphenylene group or a naphthylene group.

6. The triazine-containing heterocyclic compound according to claim 1 or 2, characterized in that The triazine-containing heterocyclic compound is selected from any one of the following compounds:

7. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises the triazine-containing heterocyclic compound according to any one of claims 1 to 6.

8. The organic electroluminescent device according to claim 7, characterized in that: The organic electroluminescent device comprises a first electrode, a second electrode and an organic layer arranged between the first electrode and the second electrode; The organic layer includes the triazine-containing heterocyclic compound.

9. The organic electroluminescent device according to claim 8, characterized in that: The organic layer includes an electron transport layer; The electron transport layer includes the triazine-containing heterocyclic compound.

10. A display device, characterized in that: The display device comprises the organic electroluminescent device according to any one of claims 7 to 9.

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