A compound containing naphthyl anthracene and its application in organic electroluminescent device

Abstract

The present invention provides a compound. The compound has a structure shown in the following formula I. The compound provided by the present invention can be used as a main material of a light-emitting layer of an OLED light-emitting device, so that the OLED light-emitting device has a lower driving voltage, a higher current efficiency and a longer life.

Description

Technical Field

[0001] The invention belongs to the technical field of organic electroluminescent materials, and in particular relates to a compound containing naphthyl anthracene and application thereof in an organic electroluminescent device. Background Art

[0002] An organic electroluminescent device is a device made by depositing one or more layers of organic materials between two metal electrodes by spin coating or vacuum evaporation. A classic three-layer organic electroluminescent device includes a hole transport layer, a light-emitting layer, and an electron transport layer. The holes generated by the anode pass through the hole transport layer and the electrons generated by the cathode pass through the electron transport layer to combine in the light-emitting layer to form excitons, and then emit light. Organic electroluminescent devices can be adjusted to emit various required lights by changing the material of the light-emitting layer as needed.

[0003] As a new type of display technology, organic electroluminescent devices have unique advantages such as self-luminescence, wide viewing angle, low energy consumption, high efficiency, thinness, rich colors, fast response speed, wide applicable temperature range, low driving voltage, the ability to produce flexible, bendable and transparent display panels, and environmental friendliness. They can be used in flat-panel displays and new generation lighting, and can also be used as LCD backlight sources.

[0004] Since its invention in the late 1980s, organic electroluminescent devices have been used in industry, such as screens for cameras and mobile phones. However, the current OLED devices are limited in their wider application due to low efficiency and short service life, especially for large-screen displays. Therefore, the efficiency of the devices needs to be improved. One of the important factors is the performance of the organic electroluminescent materials in the organic electroluminescent devices. Therefore, it is necessary to develop stable and efficient organic electroluminescent materials to improve the current efficiency and service life of OLED devices. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention aims to provide a compound and an organic electroluminescent device. The compound provided by the present invention can be used as a main material of the light-emitting layer of an OLED light-emitting device, so that the OLED light-emitting device has a lower driving voltage, higher current efficiency and longer life.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a compound having a structure shown in the following formula I:

[0008]

[0009] X is selected from O, S, CR 11 R 12 、NAr12 ;

[0010] Ar 11 Any one selected from deuterium, substituted or unsubstituted C6-C40 aryl, substituted or unsubstituted C12-C20 heteroaryl;

[0011] Ar 12 Any one selected from substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C6-C40 aryl, substituted or unsubstituted C12-C20 heteroaryl;

[0012] R 11 , R 12 are independently selected from any one of substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C6-C40 aryl, substituted or unsubstituted C12-C20 heteroaryl, and R 11 , R 12 Can be connected into rings by single bonds;

[0013] The following compounds are not included:

[0014]

[0015] Ar 11 ,Ar 12 , R 11 , R 12 The substituents are each independently selected from at least one of -D (deuterium atom), C1-C10 alkyl, C1-C6 alkoxy or C6-C15 aryl;

[0016] The hydrogen atoms in the compound represented by formula I may be independently substituted by at least one of -D (deuterium atom), -F, -CN, C1-C10 alkyl, C1-C6 alkoxy or C6-C15 aryl;

[0017] The hydrogen atoms in the compound can be independently substituted by at least one of -D, -F, -CN, C1~C10 alkyl (for example, methyl, ethyl, propyl, tert-butyl, cyclopentyl, tert-butyl, adamantyl, etc.), C1~C6 alkoxy (for example, methoxy, ethoxy, propoxy, hexyl, etc.) or C6~C15 aryl (for example, phenyl, naphthyl, fluorenyl, etc.).

[0018] In the present invention, D represents a deuterium atom, and the same shall apply hereinafter.

[0019] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the objectives and beneficial effects of the present invention can be better achieved and realized.

[0020] As a preferred technical solution of the present invention, the compound represented by formula I contains at least one D atom.

[0021] As a preferred technical solution of the present invention, the C6-C40 aromatic group is selected from any one of phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthryl, fluorenyl, benzofluorenyl, dibenzofluorenyl, naphthfluoroenyl, pyrene, perylenyl, spirofluorenyl, triphenylene, fluoranthenyl, hydrogenated benzanthryl, indenofluorenyl, benzoindenofluorenyl, dibenzoindenofluorenyl, naphthfluoroenyl or benzonaphthofluorenyl.

[0022] Preferably, the C12-C20 heteroaryl group is selected from any one of dibenzofuran, dibenzothiophene, benzodibenzofuran, benzodibenzothiophene, dinaphthofuran and dinaphthothiophene.

[0023] Preferably, Ar 11 ,Ar 12 Each is independently selected from any one of the following substituted or unsubstituted groups: phenyl, biphenyl, naphthyl, dibenzofuranyl, dibenzothienyl, benzodibenzofuranyl, fluorenyl.

[0024] The C1-C10 alkyl group is selected from methyl, ethyl, propyl, tert-butyl, cyclopentyl, tert-butyl and adamantyl.

[0025] Preferably, the Ar 11 ,Ar 12 The substituents substituted in the above-mentioned group are each independently selected from at least one of -D, methyl, ethyl, tert-butyl, adamantyl, hexyloxy, methoxy, isopropoxy, phenyl or naphthyl.

[0026] Preferably, the hydrogen atoms in the compound may be substituted by at least one of -D, methyl, ethyl, tert-butyl, adamantyl, hexyloxy, methoxy, isopropoxy, phenyl or naphthyl.

[0027] Preferably, X is selected from O and S.

[0028] Preferably, Ar11 is selected from phenyl, naphthyl, and biphenyl.

[0029] Preferably, all hydrogen atoms in Ar11 are replaced by deuterium atoms (that is, Ar11 does not contain H atoms).

[0030] Preferably, the compound represented by formula I includes compounds represented by formula I-1 to formula I-4 below:

[0031]

[0032] In Formulas I-1 to I-4, Ar 11, X has the same protection scope as above; in Formulas I-1 to I-4, one or more H atoms may be replaced by D atoms, and all H atoms in Formulas I-1 to I-4 may be replaced by deuterium atoms.

[0033] The synthesis method of the compound of formula I is not particularly limited and can be carried out using techniques known in the art.

[0034] As a preferred technical solution of the present invention, the compound of formula I is selected from any one of the following substituted or unsubstituted compounds:

[0035]

[0036]

[0037]

[0038] The substitution means that part or all of the hydrogen atoms in the above compounds are replaced by deuterium atoms. Preferably, the compound of formula I is selected from any one of the following compounds:

[0039]

[0040] In a second aspect, the present invention provides an organic electroluminescent device, comprising an anode, a cathode, and an organic thin film layer disposed between the anode and the cathode, wherein the organic thin film layer comprises the compound as described in the first aspect.

[0041] Preferably, the organic thin film layer includes a light-emitting layer, and the material of the light-emitting layer includes the compound as described in the first aspect.

[0042] In the present invention, the light-emitting layer material further comprises a compound having a structure as shown in Formula II and / or a compound having a structure as shown in Formula III:

[0043]

[0044] Among them, Ar 21 ,Ar 22 Each is independently selected from any one of a substituted or unsubstituted C6-C20 (for example, C6, C8, C10, C12, C16 or C20, etc.) aryl group, and a substituted or unsubstituted C3-C20 (for example, C3, C6, C8, C10, C12, C16 or C20, etc.) heteroaryl group;

[0045] R 21 , R 22 and R 23Each is independently selected from any one of hydrogen, C1-C12 (for example, C1, C2, C4, C6, C8, C10 or C12, etc.) straight chain or branched chain alkyl, C6-C12 (for example, C6, C8, C10 or C12, etc.) cycloalkyl;

[0046] Ar 21 ,Ar 22 The substituents in the substitution are each independently selected from C1-C5 (e.g., methyl, ethyl, propyl, n-butyl, isobutyl, tert-butyl, etc.) straight chain or branched chain alkyl or C6-C12 (e.g., phenyl, biphenyl, naphthyl, etc.) aryl;

[0047] Ar 31 ,Ar 32 ,Ar 33 and Ar 34 Each is independently selected from any one of a substituted or unsubstituted C6-C22 (for example, C6, C8, C10, C16, C18 or C22, etc.) aryl group, and a substituted or unsubstituted C12-C40 (for example, C12, C18, C20, C24, C30, C36 or C40, etc.) heteroaryl group;

[0048] R 31 Any one selected from phenyl, naphthyl or biphenyl;

[0049] a is selected from 0 or 1;

[0050] Ar 31 ,Ar 32 ,Ar 33 ,Ar 34 The substituted substituents are each independently selected from C1~C5 straight chain or branched alkyl (for example, methyl, ethyl, propyl, n-butyl, isobutyl, tert-butyl, etc.) or C6~C12 (for example, C6, C8, C10 or C12, etc.) aromatic groups.

[0051] As a preferred technical solution of the present invention, the Ar 21 ,Ar 22 Each independently selected from

[0052] Any one of .

[0053] 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.

[0054] Preferably, Ar 31 ,Ar 32 ,Ar 33 and Ar 34 Each independently selected from Any one or a combination of at least two of the following.

[0055] As a preferred technical solution of the present invention, the compound having a structure as shown in Formula II is selected from any one of the following compounds:

[0056]

[0057]

[0058] Preferably, the structure of formula II is selected from BD-2

[0059]

[0060] As a preferred technical solution of the present invention, the compound having a structure as shown in Formula III is selected from any one of the following compounds:

[0061]

[0062] Preferably, the organic thin film layer further comprises a hole layer, and the hole layer comprises a hole transport layer, a hole injection layer and an electron blocking layer.

[0063] In a third aspect, the present invention provides a display device, comprising the organic electroluminescent device as described in the third aspect.

[0064] In a fourth aspect, the present invention provides an intermediate for synthesizing the compounds of the present invention:

[0065]

[0066] Compared with the prior art, the present invention has the following beneficial effects:

[0067] The present invention designs the structure of the compound and uses it as the main material of the light-emitting layer of the OLED light-emitting device, so that the OLED light-emitting device has a lower driving voltage, a higher current efficiency and a longer life. DETAILED DESCRIPTION

[0068] For the convenience of understanding the present invention, the present invention lists the following embodiments. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0069] Preparation of intermediates

[0070] Preparation Example 1 Synthesis of Intermediate M1

[0071] This preparation example provides an intermediate M1 and a synthesis method thereof, and the synthesis method is as follows:

[0072]

[0073] Under nitrogen protection, 80 mL of toluene, 30 mL of ethanol and 15 mL of water were added to a 250 mL three-necked flask in sequence, and then 0.01 mol of 1-bromo-7-iododibenzo[b,d]furan, 0.01 mol of deuterated phenylboronic acid, 2.12 g (0.02 mol) of sodium carbonate and 0.23 g (0.0002 mol) of tetrakistriphenylphosphine palladium were added thereto. The temperature was slowly raised to 40°C for reaction for 2 h, and then raised to 60°C for reaction for 4 hours. The temperature was lowered to room temperature, and water was added to separate the organic layer. The organic layer was washed with water, dried with magnesium sulfate, and after removing the desiccant, it was concentrated to dryness, separated by silica gel column chromatography, and eluted with petroleum ether to obtain 2.7 g of intermediate M1.

[0074] The intermediate M1 obtained was subjected to mass spectrometry detection, and the two peaks with the largest mass-to-charge ratio (m / z) were measured to be 327.03 and 329.03.

[0075] Preparation Example 2-3

[0076] Referring to the synthesis method of intermediate M1 in Preparation Example 1, the following intermediates were synthesized by reacting the corresponding bromide and boronic acid compounds, and the mass spectra of the prepared intermediates were tested. The structural formulas of the corresponding bromide and boronic acid compounds and the structural formulas and mass spectrometry data of the prepared intermediates are shown in Table 1 below.

[0077] Table 1

[0078]

[0079] Synthesis Example 1 Synthesis of Compound 1

[0080] This synthesis example provides compound P1 and its synthesis method, and the synthesis method is as follows:

[0081]

[0082] Under nitrogen protection, 100 mL of toluene, 40 mL of ethanol and 15 mL of water were added to a 250 mL three-necked flask in sequence, and then 0.01 mol of intermediate P1-1, 0.01 mol of intermediate P1-2, 2.12 g (0.02 mol) of sodium carbonate and 0.23 g (0.0002 mol) of tetrakistriphenylphosphine palladium were added thereto. The temperature was slowly raised to reflux for reaction for 12 h, and the temperature was lowered to room temperature. Water was added to separate the organic layer, and the organic layer was washed with water, dried with magnesium sulfate, and after removing the desiccant, it was concentrated to dryness and separated by silica gel column chromatography. Petroleum ether: ethyl acetate = 10: 0.5 (volume ratio) was used as the eluent to obtain 4.6 g of compound P1.

[0083] The obtained compound P1 was subjected to mass spectrometry detection, and the mass-to-charge ratio (m / z) was measured to be 554.25.

[0084] Synthesis Example 2-8

[0085] Referring to the synthesis of compound P1 in Synthesis Example 1, the following compounds were synthesized by reacting the corresponding bromide and boronic acid compounds, and the mass spectra of the prepared compounds were tested. The structural formulas of the corresponding bromide and boronic acid compounds and the structural formulas and mass spectrometry data of the prepared compounds are shown in Table 2 below.

[0086] Table 2

[0087]

[0088]

[0089] Synthesis Example 9 Synthesis of Compound P5

[0090] This synthesis example provides compound P5 and its synthesis method, and the synthesis method is as follows:

[0091]

[0092] At room temperature, P5-1 (0.01 mol), palladium chloride (0.0001 mol), activated carbon (0.2 g), and D 2 O (20 mL) and C 6 D 6 (80mL), and hydrogen was introduced into it until the pressure reached 0.02MPa, and then the temperature was raised to 90°C for reaction for 120 hours, then the temperature was lowered to room temperature, filtered, and separated. The organic layer after separation was dried over magnesium sulfate, decolorized with a short silica gel column, concentrated to dryness, and vacuum dried for 24 hours to obtain compound P5 with a mass of 4.9 grams.

[0093] The mass spectrometry of compound P5 showed an m / z of 572.36.

[0094] Other compounds for which specific synthesis steps are not listed can be prepared by common knowledge in the art in combination with the above synthesis examples.

[0095] Synthesis of comparative example compounds:

[0096] Referring to the synthesis of compound P1 in Synthesis Example 1, the following comparative example compounds were synthesized by reacting the corresponding bromide and boronic acid compounds, and the mass spectra of the prepared comparative example compounds were tested. The structural formulas of the corresponding bromide and boronic acid compounds and the structural formulas and mass spectrometry data of the prepared comparative example compounds are shown in Table 3 below.

[0097] Table 3

[0098]

[0099]

[0100] The specific structures of the compounds used in the following application examples and comparative application examples are shown below:

[0101]

[0102]

[0103] Application Example 1

[0104] This application example provides an organic electroluminescent device, wherein the structure of the organic electroluminescent device is: ITO / HTL:HI-2(5%)(20nm) / HTL(50nm) / BH:BD-2(3%)(30nm) / TPBI(30nm) / Al(150nm);

[0105] The preparation method of the organic electroluminescent device is as follows:

[0106] Place each layer of material in a vacuum chamber and evacuate to 1×10 -5 ~1×10 -6 Pa, vacuum evaporated onto the cleaned ITO substrate in sequence. Among them, HTL:HI-2 (5%) (20nm) means that in this device, HTL and HI-2 are co-evaporated at a volume ratio of 95:5 to form a hole injection layer with a thickness of 20nm. BH:BD-2 (5%) (30nm) means that BH and BD-2 are co-evaporated at a volume ratio of 95:5 to form a light-emitting layer with a thickness of 30nm.

[0107] BH is a blue light host material, BD-2 is a doping material, also known as a dye. In this application example, BH is compound P1.

[0108] In the device provided in this application example, HTL:HI-2(5%) (20 nm) is a hole injection layer, and HTL (50 nm) is a hole transport layer.

[0109] Application Example 2-7

[0110] Application Examples 2-7 respectively provide an organic electroluminescent device, which differs from Application Example 1 only in that the BH material is different (the specific composition is described in Table 4 below), and the other preparation steps are the same as those of Application Example 1.

[0111] Application Examples 1-1 to 5-1 respectively provide an organic electroluminescent device, which differs from Application Examples 1 to 5 only in that the doping material BD-2 in Application Examples 1 to 5 is replaced (the specific composition is described in Table 1 below), and the other preparation steps are the same as Application Examples 1 to 5.

[0112] Comparative Application Example 1-2

[0113] Comparative Application Examples 1-4 respectively provide an organic electroluminescent device, which differs from Application Example 1 only in that the BH material is different (as described in Table 4 below), and the other preparation steps are the same as those of Application Example 1.

[0114] Performance Testing

[0115] Test method: The OLED-1000 multi-channel accelerated aging life and light color performance analysis system produced by Hangzhou Yuanfang was used for testing. The test items included the brightness, driving voltage, current efficiency, and LT80 of the organic electroluminescent device; LT80 refers to maintaining the initial brightness of the device at 1000cd / m 2 The current density remains unchanged, and the device efficiency drops to the initial brightness of 1000cd / m 2 The time required for the corresponding efficiency to reach 80%. The driving voltage, current efficiency, and LT80 are all relative values.

[0116] The specific test results are shown in Table 4 below:

[0117] Table 4

[0118]

[0119] It can be seen from the contents of Table 4 that the present invention designs the structure of the compound so that when the compound is used as a main material, its energy can be better transferred to the dye (BD-2), thereby improving the device efficiency and lifespan.

[0120] Comparison between Application Examples 1 to 4 and Application Example 5 shows that when the general structural formula of the compound conforms to Formula I-1 (all D atoms in the anthracene structure) the device efficiency is further improved and the life is further improved. Comparison between Application Examples 3 and 4 shows that when compound P4 is used as the main material, the device life is better, and when compound P5 is used as the main material, the device efficiency is better.

[0121] By comparing Application Examples 1 to 5 with Application Examples 1-1 to 5-1, it can be seen that when the doping material of the device is BD-2, the device performance is better.

[0122] Application Examples 8-12

[0123] Application Examples 8-12 respectively provide an organic electroluminescent device, which differs from Application Example 1 only in that the BH material is different (the specific composition is described in Table 5 below), and the other preparation steps are the same as those of Application Example 1.

[0124] Comparative Application Example 3

[0125] Comparative Application Example 3 provides an organic electroluminescent device, which differs from Application Example 1 only in that the BH material is different (as described in Table 5 below), and the other preparation steps are the same as those of Application Example 1.

[0126] Performance Testing

[0127] Test method: The OLED-1000 multi-channel accelerated aging life and light color performance analysis system produced by Hangzhou Yuanfang was used for testing. The test items included the brightness, driving voltage, current efficiency, and LT80 of the organic electroluminescent device; LT80 refers to maintaining the initial brightness of the device at 1000cd / m 2 The current density remains unchanged, and the device efficiency drops to the initial brightness of 1000cd / m 2 The time required for the corresponding efficiency to reach 80%. The driving voltage, current efficiency, and LT80 are all relative values.

[0128] The specific test results are shown in Table 5 below:

[0129] Table 5

[0130]

[0131] Application Example 9

[0132] Application Example 9 provides an organic electroluminescent device, which is different from Application Example 1 only in that the BH material is different (the specific composition is described in Table 6 below), and the other preparation steps are the same as those of Application Example 1.

[0133] Comparative Application Example 4

[0134] Comparative Application Example 4 provides an organic electroluminescent device, which differs from Application Example 1 only in that the BH material is different (as described in Table 6 below), and the other preparation steps are the same as those of Application Example 1.

[0135] Performance Testing

[0136] Test method: The OLED-1000 multi-channel accelerated aging life and light color performance analysis system produced by Hangzhou Yuanfang was used for testing. The test items included the brightness, driving voltage, current efficiency, and LT80 of the organic electroluminescent device; LT80 refers to maintaining the initial brightness of the device at 1000cd / m 2 The current density remains unchanged, and the device efficiency drops to the initial brightness of 1000cd / m 2 The time required for the corresponding efficiency to reach 80%. The driving voltage, current efficiency, and LT80 are all relative values.

[0137] The specific test results are shown in Table 6 below:

[0138] Table 6

[0139]

[0140]

[0141] The applicant declares that the present invention illustrates the detailed process flow of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed process flow, that is, it does not mean that the present invention must rely on the above-mentioned detailed process flow to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A compound having the structure shown in P15:

2. An organic electroluminescent device comprising the compound according to claim 1.

3. A display device, comprising the organic electroluminescent device according to claim 2.

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