An anthracene compound containing a diphenyl heterocycle and application thereof

Abstract

This invention provides an anthracene compound containing a dibenzohexane ring and its applications. The anthracene compound containing the dibenzohexane ring has the structure shown in formula BH-A. By designing the structure of the anthracene compound containing the dibenzohexane ring, this invention uses this compound as the host material for the light-emitting layer of an organic electroluminescent device, resulting in an organic electroluminescent device with lower driving voltage, higher current efficiency, and longer lifetime.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescent materials technology, specifically relating to an anthracene compound containing dibenzoheterocyclic rings and its applications. Background Technology

[0002] In 1987, Tang et al. of Kodak invented the sandwich-type organic double-layer thin-film light-emitting device. This breakthrough showed people the huge potential of OLED technology to become practical and enter the commercial market, and set off a research boom in organic light-emitting diodes.

[0003] Over the past few decades, the structure of OLED devices has evolved from the initial single-layer and double-layer structures to the current multi-layer structure, which mainly includes an anode, a hole injection layer, a hole transport layer, an electron blocking / exciton blocking layer, an organic light-emitting layer, a hole blocking / exciton blocking layer, an electron transport layer, an electron injection layer, and a metal cathode.

[0004] Currently, organic light-emitting diodes (OLEDs) have become the mainstream display technology, and correspondingly, various novel OLED materials have been developed. Therefore, there is an urgent need in this field to develop more types and higher-performance organic thin-film materials to meet the higher requirements for organic light-emitting devices. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide an anthracene compound containing dibenzohexane and its applications. By designing the structure of an anthracene compound containing dibenzohexane and using it as the main material for the light-emitting layer, the present invention enables organic electroluminescent devices to exhibit lower driving voltage, higher current efficiency, and longer lifespan.

[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 dibenzohexacyclic ring, said anthracene compound having a structure as shown in formula BH-A:

[0008]

[0009] Ar1 and Ar2 are each independently selected from any one of substituted or unsubstituted C6-C40 aryl groups and substituted or unsubstituted C12-C20 heteroaryl groups;

[0010] X is selected from O or S;

[0011] The substituents described in Ar1 and Ar2 are each independently selected from at least one of -D, -F, -CN, C1-C10 alkyl, C1-C5 alkoxy or C6-C15 aryl;

[0012] In the compound of formula BH-A, each hydrogen atom can be independently substituted by at least one of -D, -F, -CN, C1-C5 alkyl, C1-C5 alkoxy, C6-C20 aryl or C12-C20 heteroaryl.

[0013] The compounds of formula BH-A do not include compounds of formula BHAA:

[0014]

[0015] In this invention, by designing the structure of anthracene compounds containing dibenzohexane rings and controlling the substitution of hydrogen atoms on these compounds with specific substituents, anthracene compounds containing dibenzohexane rings with specific structures were obtained. The anthracene compounds containing dibenzohexane rings provided by this invention can be used as the main material for the light-emitting layer of OLED light-emitting devices, enabling these devices to have lower driving voltage, higher current efficiency, and longer lifetime.

[0016] In this invention, Ar1 and Ar2 are each independently selected from any one of substituted or unsubstituted C6-C40 (e.g., C6, C8, C10, C12, C16, C20, C24, C28, C30, C32, C36 or C40, etc.) aryl groups and substituted or unsubstituted C12-C20 (e.g., C12, C14, C16, C18 or C20, etc.) heteroaryl groups.

[0017] The substituents described in Ar1 and Ar2 are each independently selected from at least one of -D, -F, -CN, C1 to C10 alkyl (e.g., methyl, ethyl, propyl, tert-butyl, cyclopentyl, or cyclohexyl), C1 to C5 alkoxy (e.g., methoxy, ethoxy, or propoxy), or C6 to C15 aryl (e.g., phenyl or naphthyl).

[0018] The hydrogen atoms in the anthracene compounds containing dibenzoheterocyclic rings shown in formula BH-A can be independently substituted by at least one of -D, -F, -CN, C1-C5 alkyl (e.g., methyl, ethyl, or propyl), C1-C5 alkoxy (e.g., methoxy, ethoxy, or propoxy), C6-C20 aryl (e.g., phenyl, naphthyl, or biphenyl), or C12-C20 heteroaryl (e.g., dibenzothiophene or dibenzofuranyl).

[0019] In this invention, "D" represents a deuterium atom, and the same applies below.

[0020] 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.

[0021] As a preferred embodiment of the present invention, the aryl group of C6 to C40 is selected from any one of phenyl, biphenyl, terphenyl, naphthyl, anthracene, phenanthrene, fluorenyl, benzo[a]fluorenyl, dibenzo[a]fluorenyl, naphthofluorenyl, pyrene, perylene, spirofluorenyl, triphenylene, fluoranyl, hydrogenated benzo[a]anthrayl, ind[a]fluorenyl, benzo[a]ind[a]fluorenyl, dibenzo[a]ind[a]fluorenyl, or benzo[a]naphthofluorenyl.

[0022] As a preferred embodiment of the present invention, the C12-C20 heteroaryl group is selected from any one of dibenzofuranyl, dibenzothiophenyl, benzodibenzofuranyl, benzodibenzothiophenyl, dinaphthofuranyl, or dinaphthothiophenyl.

[0023] As a preferred embodiment of the present invention, the C6 to C20 aryl groups are selected from any one of phenyl, biphenyl, or naphthyl.

[0024] As a preferred embodiment of the present invention, Ar1 and Ar2 are each independently selected from any one of phenyl, biphenyl, terphenyl, fluorenyl, naphthyl, triphenylene, fluoranyl, dibenzofuranyl, dibenzothiophenyl, naphthodibenzofuranyl, and naphthodibenzothiophenyl.

[0025] As a preferred embodiment of the present invention, each hydrogen atom in the compound of formula BH-A may be independently substituted by at least one of -D, methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propoxy, phenyl, naphthyl, dibenzothiophene, and dibenzofuranyl.

[0026] As a preferred embodiment of the present invention, the compound of formula BH-A is selected from any one of the following compounds:

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036] Where X is selected from O or S.

[0037] As a preferred embodiment, the anthracene compound containing a dibenzohexacyclic ring as shown in Formula BH-A is selected from any one of the following compounds:

[0038]

[0039] It should be noted that there are no special restrictions on the preparation method of anthracene compounds containing dibenzohexacyclic rings in this invention, and commonly used preparation methods in the art are applicable.

[0040] In a second aspect, 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;

[0041] The material of the organic thin film layer includes anthracene compounds containing dibenzohexacyclic rings as described in the first aspect.

[0042] In a preferred embodiment, the organic thin film layer includes a light-emitting layer, the material of which includes anthracene compounds containing dibenzohexacyclic rings as described in the first aspect.

[0043] Thirdly, the present invention provides a display device comprising the organic electroluminescent device as described in the second aspect.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The compound of the present invention has a central structure of a dibenzoheterocyclic ring, and two aryl-substituted anthracene structures are attached to the ortho position of the benzene ring of the dibenzoheterocyclic ring. The anthracene rings in these two aryl-substituted anthracene structures are adjacent to each other and have approximately parallel stereostructures, which increases the conjugation of the entire molecular structure, enhances the charge transport capability, and is more suitable for BD. As a result, the device prepared by the present invention has a lower voltage, higher efficiency and longer lifespan. Detailed Implementation

[0046] 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.

[0047] Synthesis Example 1

[0048] This synthetic example provides a compound 1, the synthesis method of which is as follows:

[0049]

[0050] Under nitrogen protection, 80 mL of toluene and 8 mL of water were added sequentially to a 250 mL three-necked flask, followed by 3-bromo-4-chlorodibenzofuran (2.82 g, 10.0 mmol), 10-phenyl-9-anthraboronic acid (7.45 g, 25.0 mmol), potassium phosphate (8.49 g, 40.0 mmol), Pd2(dba)3 (0.18 g, 0.2 mmol), and X-Phos (0.19 g, 0.4 mmol). The mixture was slowly heated to reflux and reacted for 15 h. After cooling to room temperature, water was added to separate the contents. The organic layer was washed with water, dried over magnesium sulfate, filtered to remove magnesium sulfate, and the solvent was removed under reduced pressure. The mixture was crystallized from a mixed solvent of toluene and ethanol to obtain compound 1 (4.5 g).

[0051] The mass-to-charge ratio (m / z) of compound 1 was 672.25.

[0052] Synthesis Examples 2-8

[0053] Synthesis Examples 2-8 provide compounds 2-8 respectively. The synthesis method is the same as that of compound 1, except that 10-phenyl-9-anthraboronic acid is replaced with an equal amount of other boric acid compounds (see Table 1), and 3-bromo-4-chlorodibenzofuran is replaced with an equal amount of other dibenzofuran compounds (see Table 1). Other conditions are the same as those for the synthesis of compound 1. The synthesized compounds were detected by mass spectrometry, and the test data are shown in Table 1.

[0054] Table 1. Boric acid compounds synthesized in Examples 2-8 and their structures.

[0055]

[0056]

[0057]

[0058] Preparation Example 1

[0059] This preparation embodiment provides an intermediate M-1 and its synthesis method, the synthesis method being as follows:

[0060]

[0061] Synthesis of intermediate M-1

[0062] Under nitrogen protection, 70 mL of toluene, 35 mL of ethanol, and 35 mL of water were added sequentially to a 250 mL three-necked flask. Then, 3-bromo-4-chlorodibenzofuran (5.63 g, 20.0 mmol), 10-phenyl-9-anthracite (7.16 g, 24.0 mmol), potassium carbonate (4.14 g, 30.0 mmol), and tetraphenylphosphine palladium (0.231 g, 0.2 mmol) were added. The mixture was slowly heated to reflux and reacted for 8 h. After cooling to room temperature, water was added to separate the contents. The aqueous phase was extracted once with toluene. The organic phases were combined, washed with water, dried over magnesium sulfate, filtered to remove magnesium sulfate, and the solvent was removed under reduced pressure. The mixture of toluene and ethanol was crystallized to give compound M-1 (6.3 g).

[0063] The intermediate M-1 was analyzed by mass spectrometry, and the mass-to-charge ratio (m / z) was 454.11.

[0064] Preparation Examples 2-6

[0065] Preparation Examples 2-6 each provide an intermediate, the synthesis method of which is the same as that of intermediate M-1. The only difference is that 10-phenyl-9-anthraboronic acid in Preparation Example 1 is replaced with other boric acid compounds of equal molar amount (see Table 2), and 3-bromo-4-chlorodibenzofuran is replaced with other dibenzofuran compounds of equal molar amount (see Table 2). Other conditions are the same as those for the synthesis of intermediate M-1. The intermediates are detected by mass spectrometry, and the test data are shown in Table 2 below.

[0066] Table 2. Structures of boric acid compounds and intermediates prepared in Examples 2-6

[0067]

[0068]

[0069]

[0070] Synthesis Example 9

[0071] This synthetic example provides a compound 9, the synthesis method of which is as follows:

[0072]

[0073] Under nitrogen protection, 100 mL of toluene and 10 mL of water were added sequentially to a 250 mL three-necked flask, followed by M-1 (4.55 g, 10.0 mmol), 10-(1-naphthyl)-9-anthraboronic acid (4.18 g, 12.0 mmol), potassium phosphate (6.37 g, 30.0 mmol), Pd2(dba)3 (0.09 g, 0.1 mmol), and X-Phos (0.095 g, 0.2 mmol). The mixture was slowly heated to reflux and reacted for 18 h. After cooling to room temperature, water was added to separate the contents. The organic layer was washed with water, dried over magnesium sulfate, filtered to remove magnesium sulfate, and the solvent was removed under reduced pressure. The mixture was crystallized from a mixed solvent of toluene and ethanol to obtain compound 9 (4.1 g).

[0074] Compound 9 was analyzed by mass spectrometry, and its mass-to-charge ratio (m / z) was 722.26.

[0075] Synthesis Examples 10-17

[0076] Synthesis Examples 10-17 provide compounds 10-17 respectively. The synthesis method is the same as that of compound 9, except that intermediate M-1 is replaced with an equal amount of one of intermediates M-1 to M-6 (see Table 3), and 10-(1-naphthyl)-9-anthraboronic acid is replaced with an equal amount of other boric acid compounds (see Table 3). Other conditions are the same as those for the synthesis of compound 9. The synthesized compounds were analyzed by mass spectrometry, and the test data are shown in Table 3.

[0077] Table 3. Structures of intermediates, borate compounds, and synthesized compounds in Examples 10-17.

[0078]

[0079]

[0080] Preparation Example 7

[0081] This preparation embodiment provides an intermediate M-3S and its synthesis method, the synthesis method being as follows:

[0082]

[0083] (1) Synthesis of intermediate M-1S

[0084] Under nitrogen protection, 140 mL of toluene, 70 mL of ethanol, and 70 mL of water were added sequentially to a 500 mL three-necked flask. Then, 2-methylthiophenylboronic acid (6.72 g, 40.0 mmol), 2-bromo-1-chloro-3-iodobenzene (15.87 g, 50.0 mmol), potassium carbonate (8.28 g, 60.0 mmol), and tetraphenylphosphine palladium (0.462 g, 0.4 mmol) were added. The mixture was slowly heated to reflux and reacted for 8 h. After cooling to room temperature, water was added to separate the contents. The aqueous phase was extracted once with toluene. The organic phases were combined, washed with water, dried over magnesium sulfate, filtered to remove magnesium sulfate, and the solvent was removed under reduced pressure. The mixture was crystallized from a toluene and ethanol mixture to obtain compound M-1S (8.1 g).

[0085] Mass spectrometry analysis of intermediate M-1S revealed two peaks with the largest mass-to-charge ratio (m / z): 311.94 and 313.94.

[0086] (2) Synthesis of intermediate M-2S

[0087] Under nitrogen protection, M-1S (7.84 g, 25 mmol), 3.9 mL of 30% hydrogen peroxide solution, and 80 mL of acetic acid were added sequentially to a 250 mL three-necked flask. The reaction was carried out at 0 °C. The reaction was monitored by liquid phase until the reaction endpoint was reached. The reaction solution was washed with 200 mL of water, and then 200 mL of ethyl acetate was added to extract and separate the layers. The aqueous phase was extracted once more with 200 mL of ethyl acetate. The organic phases were combined, dried over magnesium sulfate, filtered to remove magnesium sulfate, and the solvent was removed under reduced pressure. The mixture was then slurried with petroleum ether and dried to obtain compound M-2S (6.3 g).

[0088] Mass spectrometry analysis of intermediate M-2S revealed two peaks with the largest mass-to-charge ratio (m / z): 327.93 and 329.93.

[0089] (3) Synthesis of intermediate M-3S

[0090] Under nitrogen protection, M-2S (5.93 g, 18 mmol), 80 mL of dichloroethane, and 12 mL of 10% phosphorus pentoxide methanesulfonic acid solution were added sequentially to a 250 mL three-necked flask. The temperature was slowly raised to 80 °C, and the reaction was monitored by liquid phase until the endpoint was reached. The reaction solution was washed with 200 mL of water, and the pH was adjusted to between 7 and 8 using triethylamine. The mixture was then filtered, slurried with ethanol, and dried to obtain compound M-3S (4.1 g).

[0091] Mass spectrometry analysis of intermediate M-3S revealed two peaks with the largest mass-to-charge ratio (m / z): 295.91 and 297.90.

[0092] Synthesis Example 18

[0093] This embodiment provides a compound 18 and its synthesis method, the synthesis method being as follows:

[0094]

[0095] Under nitrogen protection, 80 mL of toluene and 80 mL of water were added sequentially to a 250 mL three-necked flask, followed by M-3S (2.98 g, 10.0 mmol), 10-phenyl-9-anthraboric acid (7.45 g, 25.0 mmol), potassium phosphate (8.49 g, 40.0 mmol), Pd2(dba)3 (0.09 g, 0.1 mmol), and X-Phos (0.095 g, 0.2 mmol). The mixture was slowly heated to reflux and reacted for 15 h. After cooling to room temperature, water was added to separate the contents. The organic layer was washed with water, dried over magnesium sulfate, filtered to remove magnesium sulfate, and the solvent was removed under reduced pressure. The mixture was crystallized from a mixed solvent of toluene and ethanol to obtain compound 18 (3.6 g).

[0096] Compound 18 was analyzed by mass spectrometry, and its mass-to-charge ratio (m / z) was 688.22.

[0097] For other compounds whose specific synthesis methods are not listed, they can be synthesized by referring to the above examples and combining them with common knowledge in the field.

[0098] The specific structures of some of the substances used in the following application examples and comparative examples are as follows:

[0099]

[0100]

[0101] Application Example 1

[0102] This application example provides an organic electroluminescent device, using compound 1 provided in synthesis example 1 of the present invention as the main material of the light-emitting layer;

[0103] The structure of the organic electroluminescent device is: ITO / HT (40nm) / light-emitting layer main material: BD-23% (30nm) / TPBI (30nm) / LiF (0.5nm) / Al (150nm).

[0104] The fabrication method of the above-mentioned organic electroluminescent device is as follows:

[0105] The glass substrate coated with an ITO transparent conductive layer (as the anode) was ultrasonically treated in a cleaning agent, then rinsed in deionized water, then ultrasonically degreased in a mixed solvent of acetone and ethanol, then baked in a clean environment until completely dehydrated, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam to improve the surface properties and enhance the bonding ability with the hole layer.

[0106] The 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. The light-emitting layer substrate material: BD-2 3% (30nm) refers to the fact that in the device, the light-emitting layer substrate material and BD-2 are co-evaporated at a volume ratio of 97:3 to form the light-emitting layer, with a thickness of 30nm.

[0107] Application Examples 2-12

[0108] Application Examples 2-12 provide an organic electroluminescent device, which differs from Application Example 1 only in that the main material of the light-emitting layer is different (see Table 4 for details), while other conditions are the same as in Application Example 1.

[0109] Application Comparative Examples 1-3

[0110] Comparative Examples 1 to 3 each provide an organic electroluminescent device, which differs from Application Example 1 only in that the main material of the light-emitting layer is different (see Table 4 for details), while other conditions are the same as Application Example 1.

[0111] Performance testing

[0112] The driving voltage, current efficiency, and lifetime (LT90) of the OLED devices provided above were tested. LT90 refers to the time required for the brightness to decrease to 90% of its original brightness while maintaining an initial brightness of 1000 nits at a constant current density. Test items included the brightness, driving voltage, and current efficiency of the organic electroluminescent device. The driving voltage, current efficiency, and LT90 data were all based on a brightness of 1000 cd / m². 2 The relative value at time.

[0113] The performance test results of the organic electroluminescent devices are shown in Table 4.

[0114] Table 4. Test results of the main material and device performance of the emitting layer in Application Examples 1-12 and Comparative Examples 1-3.

[0115]

[0116] As shown in Table 4, this invention, through the design of the structure of anthracene compounds containing dibenzohexane rings, has obtained anthracene compounds with specific structures. The anthracene compounds containing dibenzohexane rings provided by this invention can be used as the main material for the light-emitting layer of organic electroluminescent devices, enabling these devices to have lower driving voltage, higher current efficiency, and longer lifetime.

[0117] Compared with Comparative Examples 1-3, the compound of the present invention has a central structure of a dibenzoheterocyclic ring, and two aryl-substituted anthracene structures are attached to the ortho position of the benzene ring of the dibenzoheterocyclic ring. Since the anthracene rings in these two aryl-substituted anthracene structures are in adjacent positions and their stereo positions are approximately parallel, the conjugation of the entire molecular structure is increased, the charge transport capability is enhanced, and it is more suitable for pairing with BD. As a result, the device prepared by the present invention has a lower voltage, higher efficiency and longer lifespan.

[0118] Application Examples 13-14

[0119] Application Examples 13-14 provide an organic electroluminescent device, which differs from Application Example 1 only in that the main material of the light-emitting layer is different (see Table 5 for details), and BD-2 is replaced with BD-3. All other conditions are the same as in Application Example 1.

[0120] Application Comparative Example 4

[0121] Comparative Example 4 provides an organic electroluminescent device, which differs from Application Example 1 only in that the main material of the light-emitting layer is different (see Table 5 for details), and BD-2 is replaced with BD-3. All other conditions are the same as in Application Example 1.

[0122] Performance testing

[0123] The driving voltage, current efficiency, and lifetime (LT90) of the OLED devices provided above were tested. LT90 refers to the time required for the brightness to decrease to 90% of its original brightness while maintaining an initial brightness of 1000 nits at a constant current density. Test items included the brightness, driving voltage, and current efficiency of the organic electroluminescent device. The driving voltage, current efficiency, and LT90 data were all based on a brightness of 1000 cd / m². 2 The relative value at time.

[0124] The performance test results of the organic electroluminescent devices are shown in Table 5.

[0125] Table 5

[0126]

[0127] 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 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; the organic thin film layer includes a light-emitting layer, with an anthracene compound containing dibenzohexane as the main material of the light-emitting layer; the structure of the organic electroluminescent device is: ITO / HT (40nm) / light-emitting layer main material: BD-3 3% (30nm) / TPBI (30nm) / LiF (0.5nm) / Al (150nm); The method for fabricating the organic electroluminescent device is as follows: A glass substrate coated with an ITO transparent conductive layer was used as the anode and ultrasonically treated in a cleaning agent. Then it was rinsed in deionized water, ultrasonically degreased in a mixed solvent of acetone and ethanol, baked in a clean environment until completely dehydrated, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam to improve the surface properties and enhance the bonding ability with the hole layer. The material is placed in a vacuum chamber, vacuumed to 1x10 -5 ~1x10 -6 Pa, vacuum evaporated onto a cleaned ITO substrate in sequence; wherein the light-emitting layer host material: BD-3 3% (30 nm) means that in the device, the light-emitting layer host material and BD-3 are co-evaporated to form a light-emitting layer in a volume ratio of 97:3, and the thickness of the light-emitting layer is 30 nm; The structure of BD-3 is shown below: ； The anthracene compound containing a dibenzohexacyclic ring is selected from any one of the following compounds: 。 2. A display device, characterized in that, The display device includes the organic electroluminescent device as described in claim 1.

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