An anthracene compound containing a diphenyl pentaheterocyclic ring substituent, an intermediate and an organic electroluminescent device

Abstract

The application provides an anthracene compound containing a diphenyl pentaheterocyclic substituent, an intermediate and an organic electroluminescent device. The anthracene compound containing the diphenyl pentaheterocyclic substituent has a structure of formula I. The anthracene compound containing the diphenyl pentaheterocyclic substituent provided by the application can be used as a main body material of an OLED device light-emitting layer, so that the OLED device has a lower driving voltage, a higher current efficiency and a longer service life.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescent materials technology, specifically relating to an anthracene compound containing a dibenzo-p-5 heterocyclic substituent, an intermediate, and an organic electroluminescent device. Background Technology

[0002] Organic light-emitting diodes (OLEDs) are devices fabricated by depositing one or more layers of organic material between two metal electrodes via spin coating or vacuum evaporation. A classic three-layer OLED comprises a hole transport layer, an emissive layer, and an electron transport layer. Holes generated by the anode combine with electrons generated by the cathode via the electron transport layer in the emissive layer to form excitons, which then emit light. OLEDs can be tuned to emit various desired light colors by changing the material of the emissive layer.

[0003] Organic electroluminescent devices, as a novel display technology, possess unique advantages such as self-illumination, wide viewing angle, low energy consumption, high efficiency, thinness, rich colors, fast response speed, wide applicable temperature range, low driving voltage, the ability to manufacture flexible, bendable, and transparent display panels, and environmental friendliness. They can be applied to flat panel displays and next-generation lighting, and can also be used as backlights for LCDs.

[0004] Since their invention in the late 1980s, organic light-emitting diodes (OLEDs) have been used in various industries, such as as screens in cameras and mobile phones. However, current OLED devices suffer from low efficiency and short lifespan, limiting their wider application, especially in large-screen displays. Therefore, it is necessary to improve the efficiency of these devices. One crucial factor limiting this is the performance of the organic light-emitting materials used in OLEDs. Thus, it is essential to develop stable and efficient organic light-emitting materials to improve the current efficiency and lifespan of OLED devices. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide anthracene compounds containing dibenzo5-membered heterocyclic substituents, intermediates, and organic electroluminescent devices. The anthracene compounds containing dibenzo5-membered heterocyclic substituents provided by the present invention can serve as the host material for the light-emitting layer of OLED devices, enabling OLED devices to exhibit lower driving voltage, higher current efficiency, and longer lifetime.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides an anthracene compound containing a dibenzo-5-membered heterocyclic substituent, wherein the anthracene compound containing the dibenzo-5-membered heterocyclic substituent has the structure shown in Formula I:

[0008]

[0009] R1-R7 are each independently selected from any one of hydrogen atom, deuterium atom, substituted or unsubstituted C6-C40 aryl, substituted or unsubstituted C12-C20 heteroaryl;

[0010] X is selected from O or S;

[0011] One of A and B is selected from a hydrogen atom or a deuterium atom, and the other is selected from any one of substituted or unsubstituted C6-C40 aryl or substituted or unsubstituted C12-C20 heteroaryl;

[0012] C is selected from any one of substituted or unsubstituted C6-C40 aryl groups and substituted or unsubstituted C12-C20 heteroaryl groups;

[0013] The substituents described in R1-R7, A, B, and C are each independently selected from at least one of -D (deuterium atom), C1-C10 alkyl, C1-C6 alkoxy, or C6-C15 aryl.

[0014] This invention designs the structure of anthracene compounds containing dibenzo5-membered heterocyclic substituents to make them suitable as the main material for the light-emitting layer of OLED devices, thereby enabling OLED devices to have lower driving voltage, higher current efficiency, and longer lifespan.

[0015] In this invention, D represents a deuterium atom, and the same applies below.

[0016] In this invention, C6-C40 can be C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36 or C40, etc.

[0017] C12-C20 can be C12, C13, C14, C15, C16, C17, C18, C19 or C20.

[0018] C1-C10 can be C1, C2, C3, C4, C5, C6, C7, C8, C9 or C10.

[0019] C6-C15 can be C6, C8, C10, C12, or C15, etc.

[0020] C1-C6 can be C1, C2, C3, C4, C5, or C6.

[0021] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The purpose and beneficial effects of the present invention can be better achieved and realized through the following preferred technical solutions.

[0022] As a preferred embodiment of the present invention, the C6-C40 aryl group is selected from any one of phenyl, biphenyl, terphenyl, naphthyl, anthracene, phenanthrene, fluorenyl, benzo[a]fluorenyl, dibenzo[a]fluorenyl, naphthyl, pyrene, perylene, spirofluorenyl, triphenylene, fluoranyl, hydrogenated benzo[a]anthrayl, ind[a]fluorenyl, benzo[a]ind[a]fluorenyl, dibenzo[a]ind[a]fluorenyl, naphthyl, or benzo[a]naphthyl.

[0023] Preferably, the C12-C20 heteroaryl group is selected from any one of dibenzofuranyl, dibenzothiophenyl, benzodibenzofuranyl, benzodibenzothiophenyl, dinaphthofuranyl, and dinaphthothiophenyl.

[0024] Preferably, the C1-C10 alkyl group is selected from any one of methyl, ethyl, propyl, n-butyl, tert-butyl, cyclopentyl, cyclohexyl, octyl, and adamantyl.

[0025] Preferably, the C1-C6 alkoxy group is selected from any one of methoxy, ethoxy, propoxy, butoxy, pentoxy, and hexoxy.

[0026] Preferably, the C6-C15 aryl group is selected from any one of phenyl, naphthyl, biphenyl, anthracene, phenanthryl, or fluorenyl.

[0027] As a preferred embodiment of the present invention, R1, R2, and R3 are each independently selected from any one of hydrogen atom, deuterium atom, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, and substituted or unsubstituted naphthyl.

[0028] The substituent is selected from any one of methyl, ethyl, propyl, butyl, methoxy, or ethoxy.

[0029] Preferably, R4, R5, R6, and R7 are each independently selected from any one of hydrogen atom, deuterium atom, phenyl, biphenyl, or naphthyl.

[0030] As a preferred embodiment of the present invention, C and B are each independently selected from any one of substituted or unsubstituted C6-C40 aryl groups and substituted or unsubstituted C12-C20 heteroaryl groups.

[0031] Preferably, C and B represent the same substituent.

[0032] Preferably, C and B represent different substituents.

[0033] Preferably, A and C are each independently selected from any one of substituted or unsubstituted C6-C40 aryl groups and substituted or unsubstituted C12-C20 heteroaryl groups.

[0034] Preferably, A and C represent the same substituent.

[0035] Preferably, A and C represent different substituents.

[0036] Preferably, either A or B is selected from hydrogen or deuterium, and the other is selected from phenyl, biphenyl, or naphthyl.

[0037] Preferably, C is selected from any one of phenyl, biphenyl, or naphthyl.

[0038] As a preferred embodiment of the present invention, the compound of Formula I is selected from any one of the following substituted or unsubstituted compounds:

[0039]

[0040]

[0041] The substitution refers to the fact that each hydrogen atom in the above compound can be independently replaced by a deuterium atom.

[0042] Preferably, the compound of formula I is selected from any one of the following compounds:

[0043]

[0044] In a second aspect, the present invention provides an intermediate comprising a compound having the structure shown in the following formula:

[0045]

[0046] Among them, X, A, B, and C have the same definitions as above;

[0047] X1 is selected from any one of H, F, Cl, Br or I;

[0048] X2 is selected from any one of H, F, Cl, Br, I or R5, where R5 has the same definition as above;

[0049] The intermediate is used to prepare anthracene compounds containing dibenzo5-membered heterocyclic substituents as described in the first aspect.

[0050] Preferably, the intermediate is selected from the following compounds:

[0051]

[0052] Thirdly, the present invention provides an organic electroluminescent device, the organic electroluminescent device comprising an anode, a cathode and an organic thin film layer disposed between the anode and the cathode, the organic thin film layer comprising an anthracene compound containing a dibenzo5-membered heterocyclic substituent as described in the first aspect.

[0053] Preferably, the organic thin film layer includes a light-emitting layer, the material of which includes anthracene compounds containing dibenzo-p-5-membered heterocyclic substituents as described in the first aspect.

[0054] Preferably, the organic thin film layer further includes a hole layer, which includes a hole transport layer, a hole injection layer, and an electron blocking layer;

[0055] The material of the cavity layer includes anthracene compounds containing dibenzo5-membered heterocyclic substituents as described in the first aspect.

[0056] In this invention, the light-emitting layer material further includes compounds having the structure shown in Formula II and / or compounds having the structure shown in Formula III:

[0057]

[0058] Among them, Ar 21 Ar 22 Each is independently selected from any one of substituted or unsubstituted C6-C20 (e.g., C6, C8, C10, C12, C16, or C20, etc.) aryl, substituted or unsubstituted C3-C20 (e.g., C3, C6, C8, C10, C12, C16, or C20, etc.) heteroaryl;

[0059] R 21 R 22 and R 23 Each is independently selected from hydrogen, C1-C12 (e.g., C1, C2, C4, C6, C8, C10 or C12, etc.) straight-chain or branched alkyl groups, and C6-C12 (e.g., C6, C8, C10 or C12, etc.) cycloalkyl groups;

[0060] Ar 21 Ar 22 The substituents described herein are each independently selected from C1-C5 (e.g., methyl, ethyl, propyl, n-butyl, isobutyl, tert-butyl, etc.) straight-chain or branched alkyl groups or C6-C12 (e.g., phenyl, diphenyl, naphthyl, etc.) aryl groups;

[0061] Ar 31 Ar 32 Ar 33 and Ar 34 Each is independently selected from any one of substituted or unsubstituted C6-C22 (e.g., C6, C8, C10, C16, C18, or C22, etc.) aryl, substituted or unsubstituted C12-C40 (e.g., C12, C18, C20, C24, C30, C36, or C40, etc.) heteroaryl;

[0062] R31 Selected from any one of phenyl, naphthyl, or biphenyl;

[0063] a is selected from 0 or 1;

[0064] Ar 31 Ar 32 Ar 33 Ar 34 The substituents described herein are each independently selected from C1-C5 straight-chain or branched alkyl groups (e.g., methyl, ethyl, propyl, n-butyl, isobutyl, tert-butyl, etc.) or C6-C12 (e.g., C6, C8, C10, or C12, etc.) aryl groups.

[0065] As a preferred technical solution of the present invention, the Ar 21 Ar 22 Each independently selected

[0066] Any of the following, short bonds represent connection sites.

[0067] Preferably, the R 21 R 22 and R 23 Each is independently selected from any one of hydrogen, methyl, ethyl, propyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclohexyl, or adamantyl.

[0068] Preferably, the Ar 31 Ar 32 Ar 33 and Ar 34 Each independently selected Any one or at least two of them, short bonds represent connection sites.

[0069] As a preferred embodiment of the present invention, the compound of formula II is selected from any one of the following compounds:

[0070]

[0071]

[0072] As a preferred embodiment of the present invention, the compound of formula III is selected from any one of the following compounds:

[0073]

[0074] Fourthly, the present invention provides a display device comprising the organic electroluminescent device as described in the third aspect.

[0075] Compared with the prior art, the present invention has the following beneficial effects:

[0076] This invention designs the structure of anthracene compounds containing dibenzo5-membered heterocyclic substituents and uses them as the main material for the light-emitting layer of OLED devices, thereby enabling OLED devices to have lower driving voltage, higher current efficiency and longer lifespan. Detailed Implementation

[0077] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0078] Preparation Example 1

[0079] This preparation example provides intermediates M11 and M12 and their synthesis method, which is as follows:

[0080]

[0081] In a three-necked flask, 3.2 g of the compound shown in M10 was added, followed by 80 mL of DMF. Then, 1.9 g of NBS (N-bromosuccinimide) was added in portions at 25 °C. After the addition was complete, the mixture was reacted at room temperature for 24 hours. The mixture was then added to water, filtered to obtain a solid, dried, and separated by silica gel column chromatography. The solid was eluted with petroleum ether to give 0.8 g of intermediate M11 and 1.1 g of intermediate M12.

[0082] The obtained intermediates M11 and M12 were subjected to mass spectrometry, and the mass-to-charge ratio (m / z) of both were measured to be 398.03.

[0083] The obtained intermediate M11 was subjected to NMR analysis, and the data are as follows: 1H-NMR (Bruker, Switzerland, Avance II 400MHz NMR spectrometer, CDCl3), δ8.03 (m, 1H), δ7.88 (s, 1H), δ7.53~7.33 (m, 12H), δ7.31 (m, 1H).

[0084] The obtained intermediate M12 was subjected to NMR analysis, and the data are as follows: 1H-NMR (Bruker, Switzerland, Avance II 400MHz NMR spectrometer, CDCl3), δ8.07 (d, 1H), δ8.01 (d, 1H), δ7.86 (d, 1H), δ7.80~7.71 (m, 4H), δ7.50~7.33 (m, 8H).

[0085] Preparation Example 2

[0086] This preparation example provides intermediates M21 and M22 and their synthesis method, which is as follows:

[0087]

[0088] Intermediates M21 and M22 were prepared by referring to the method of Preparation Example 1.

[0089] The obtained intermediates M21 and M22 were subjected to mass spectrometry, and the mass-to-charge ratio (m / z) of both were measured to be 398.03.

[0090] The obtained intermediate M21 was subjected to NMR analysis, and the data are as follows: 1H-NMR (Bruker, Switzerland, Avance II 400MHz NMR spectrometer, CDCl3), δ8.17 (s, 1H), δ7.89 (m, 1H), δ7.54~7.28 (m, 13H).

[0091] The obtained intermediate M22 was subjected to NMR analysis, and the data are as follows: 1H-NMR (Bruker, Switzerland, Avance II 400MHz NMR spectrometer, CDCl3), δ8.06 (d, 1H), δ7.85~7.75 (m, 4H), δ7.52~7.33 (m, 10H).

[0092] Preparation Example 3

[0093] This preparation example provides intermediates M13 and M14 and their synthesis method, which is as follows:

[0094]

[0095] (1) Synthesis of intermediate M13

[0096] Under nitrogen protection, 80 mL of toluene, 40 mL of ethanol, and 15 mL of water were added sequentially to a three-necked flask. Then, 4.0 g of intermediate M12, 1.3 g of phenylboronic acid, 2.12 g (0.02 mol) of sodium carbonate, and 0.23 g (0.0002 mol) of tetrakis(triphenylphosphine)palladium were added. The mixture was slowly heated to reflux and reacted for 8 hours. After cooling to room temperature, water was added to separate the contents. The organic layer was washed with water and dried with magnesium sulfate. After removing the desiccant, the mixture was concentrated to dryness and crystallized from ethanol to obtain 2.6 g of intermediate M13.

[0097] The obtained intermediate M13 was subjected to mass spectrometry analysis, and the mass-to-charge ratio (m / z) was measured to be 396.15.

[0098] (2) Synthesis of intermediate M14

[0099] Intermediate M14 was prepared by referring to the synthesis method of intermediate M11.

[0100] The obtained intermediate M14 was subjected to mass spectrometry analysis, and the mass-to-charge ratio (m / z) was measured to be 474.06.

[0101] Synthesis Example 1

[0102] This synthetic example provides compound P1 and its synthetic method, which is as follows:

[0103]

[0104] Compound P1 was prepared by referring to the synthesis method of intermediate M13.

[0105] The obtained compound P1 was analyzed by mass spectrometry, and the mass-to-charge ratio (m / z) was found to be 572.21.

[0106] Synthesis Examples 2-9

[0107] Referring to the synthesis of compound 1 in Example 1, the following compounds were synthesized by reacting the corresponding brominated derivatives and borate compounds, and the mass spectra of the prepared compounds were measured. The structural formulas of the corresponding brominated derivatives and borate compounds, as well as the structural formulas and mass spectrometry data of the prepared compounds, are detailed in Table 1 below.

[0108] Table 1

[0109]

[0110]

[0111]

[0112] Other compounds for which specific synthetic steps are not listed can be prepared using common knowledge in the field, combined with the above synthetic examples.

[0113] The specific structures of the compounds used in the following application examples and comparative application examples are shown below:

[0114]

[0115]

[0116] Application Example 1

[0117] This application example provides an organic electroluminescent device with the following structure: ITO / HTL:HI-2(5%) (20nm) / HTL(50nm) / BH:BD-1(5%) (30nm) / TPBI(30nm) / Al(150nm);

[0118] The fabrication method of the above-mentioned organic electroluminescent device is as follows:

[0119] Each layer of material was placed inside a vacuum chamber, and the vacuum was evacuated to 1×10⁻⁶. -5 ~1×10 -6 Pa is sequentially vacuum-deposited onto the cleaned ITO substrate. Here, HTL:HI-2 (5%) (20nm) refers to the co-evaporation of HTL and HI-2 at a volume ratio of 95:5 to form a hole injection layer with a thickness of 20nm. BH:BD-1 (5%) (30nm) refers to the co-evaporation of BH and BD-1 at a volume ratio of 95:5 to form a light-emitting layer with a thickness of 30nm.

[0120] BH is the main material for blue light emission. In this application example, BH is compound P1.

[0121] In the device provided in this application example, HTL:HI-2(5%) (20nm) is the hole injection layer, and HTL(50nm) is the hole transport layer.

[0122] Application Example 2-10

[0123] Application Examples 2-10 each provide an organic electroluminescent device. The only difference between them and Application Example 1 is that the BH material is different (the specific composition is described in Table 2 below). The other preparation steps are the same as in Application Example 1.

[0124] Comparative Application Examples 1-3

[0125] Comparative Application Examples 1-3 provide an organic electroluminescent device, which differs from Application Example 1 only in the BH material (details are described in Table 2 below), while the other preparation steps are the same as in Application Example 1.

[0126] The test items include the brightness, driving voltage, current efficiency, and LT80 of the organic electroluminescent device; where LT80 refers to maintaining the device's initial brightness of 1000 cd / m². 2 With the current density remaining constant, the device efficiency drops to the initial luminance of 1000 cd / m². 2 The time required to achieve 80% of the corresponding efficiency. The drive voltage, current efficiency, and LT80 are all relative values.

[0127] The specific test results are shown in Table 2 below:

[0128] Table 2

[0129]

[0130]

[0131] As can be seen from the above, this invention designs the structure of anthracene compounds containing dibenzo-p-5-membered heterocyclic substituents and uses them as the main material of the light-emitting layer of OLED devices, thereby enabling OLED devices to have lower driving voltage, higher current efficiency and longer lifespan.

[0132] By comparing application example 3 with application example 1-2, we can see that:

[0133] Based on the blue light host material BH3, substituents were added to the dibenzo5-membered heterocyclic group to obtain BH1 and BH2.

[0134] To reduce the voltage of blue light-emitting devices, the absolute value of the HOMO (Homo Optimum Occurrence Modulation) of the blue light-emitting host material needs to be reduced to improve hole transfer. This is typically achieved by increasing conjugation. However, while increasing conjugation reduces the absolute value of the HOMO, it also decreases the energy transfer capacity (Eg) of the material. This makes energy transfer from the blue light-emitting host material to the doped material (BD), thus affecting device efficiency.

[0135] To increase the degree of conjugation of materials to reduce device voltage and improve efficiency, it is necessary to rationally design the types and positions of substituents on the BH3 structure. This invention rationally selects the types of A, B, and C, and at the same time rationally selects the substitution positions (R1, R2, R3) of the phenyl group in Formula I, so as to improve device voltage, efficiency, and lifetime.

[0136] By comparing Application Examples 1 and 3 with Application Examples 6 and 7, it can be seen that when A and C in Formula I are selected from substituted or unsubstituted C6-C40 aryl or substituted or unsubstituted C12-C20 heteroaryl, the driving voltage of the prepared OLED device is lower; when C and B are selected from substituted or unsubstituted C6-C40 aryl or substituted or unsubstituted C12-C20 heteroaryl, the current efficiency and lifetime of the prepared OLED device are better.

[0137] Furthermore, it is known that when compound P21 is used as the main blue light source material, the device voltage and efficiency are superior. When compound P22 is used as the main blue light source material, the device lifetime is good.

[0138] In summary, this invention designs the structure of anthracene compounds containing dibenzo5-membered heterocyclic substituents and uses them as the main material for the light-emitting layer of OLED devices, thereby enabling OLED devices to have lower driving voltage, higher current efficiency, and longer lifespan.

[0139] The applicant declares that the detailed process flow of this invention is illustrated by the above embodiments, but this invention is not limited to the above detailed process flow, that is, it does not mean that this invention must rely on the above detailed process flow to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the product of this invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

Claims

1. An anthracene compound containing a dibenzo5-membered heterocyclic substituent, characterized in that, The anthracene compound containing a dibenzo5-membered heterocyclic substituent is .

2. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes an anode, a cathode, and an organic thin film layer disposed between the anode and the cathode, wherein the organic thin film layer includes anthracene compounds containing dibenzo-p-5 heterocyclic substituents as described in claim 1.

3. The organic electroluminescent device according to claim 2, characterized in that, The organic thin film layer includes a light-emitting layer, and the material of the light-emitting layer includes anthracene compounds containing dibenzo-p-5-membered heterocyclic substituents as described in claim 1.

4. The organic electroluminescent device according to claim 3, characterized in that, The material of the light-emitting layer also includes compound BD-1: .

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