An amine compound with a deuterated fluorene group and an organic light emitting device

Abstract

The application discloses an amine-based compound with a deuterated fluorene group, which is selected from formula 1 to formula 3, wherein Ar1 and Ar2 are the same or different and are selected from substituted or unsubstituted C5-C40 aromatic hydrocarbon groups and substituted or unsubstituted C5-C40 heteroaromatic hydrocarbon groups. The organic electroluminescent material of the application introduces heavy hydrogen (deuterium) into a conventional organic material, the introduction of deuterium improves the chemical stability and thermal stability of the material and the doped material, thereby greatly improving the luminous efficiency and stability of the device. Meanwhile, the compound of the application has a large torque, so that the compound has a high triplet energy level and good film-forming property.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescence technology, specifically relating to an amine compound with a deuterated fluorene group and an organic light-emitting device. Background Technology

[0002] Organic light-emitting devices (OLEDs) are self-emissive light-emitting devices that utilize the following principle: when an electric field is applied, fluorescent material emits light through the recombination of holes injected at the positive electrode and electrons injected at the negative electrode. These self-emissive devices possess characteristics such as low voltage, high brightness, wide viewing angle, fast response, and good temperature adaptability. Furthermore, they are ultra-thin and can be fabricated on flexible panels, making them widely used in mobile phones, tablets, televisions, lighting, and other fields.

[0003] Organic electroluminescent devices (OLEDs) have a sandwich-like structure, consisting of electrode material layers and organic functional materials sandwiched between them. These various functional materials are stacked together according to their intended use to form the OLED. As a current-carrying device, when a voltage is applied to the two electrodes of the OLED, positive and negative charges are generated in the organic functional material layers through the action of an electric field. These positive and negative charges then recombine in the light-emitting layer, producing light; this process is called electroluminescence.

[0004] Research on improving the performance of organic electroluminescent devices includes reducing the driving voltage, increasing luminous efficiency, and extending lifespan. To continuously improve the performance of organic electroluminescent devices, innovation in their structure and fabrication processes is needed, along with ongoing research and innovation in organic electroluminescent functional materials to create higher-performance organic electroluminescent functional materials.

[0005] Triarylamine compounds are common organic electroluminescent materials. Based on the triarylamine structure, we are exploring to find more high-performance electroluminescent materials. The invention patent with publication number CN115304567B discloses an organic compound that improves device performance by introducing methylfluorene into the triarylamine structure. However, due to the continuous development and iteration of screens, it is necessary to further develop organic electroluminescent materials with better performance. Summary of the Invention

[0006] The purpose of this invention is to provide an amine compound with a deuterated fluorene group and its organic electroluminescent device, based on the prior art.

[0007] The technical solution of the present invention is as follows:

[0008] An amino compound containing a deuterated fluorene group, selected from compounds shown in Formulas 1-3:

[0009]

[0010] Wherein, Ar1 and Ar2 are the same or different and are selected from substituted or unsubstituted phenyl, naphthyl, anthracene, phenanthryl, fluorenyl, oxofluorenyl, 9,9-spirodifluorenyl group, 9,9-dimethylfluorenyl group, 9,9-diphenylfluorenyl group, carbazolyl, N-ethylcarbazolyl, 4-hydroxycarbazolyl, benzocarbazolyl, benzothiophene, furanyl, thiophene, phenylpyrimidinyl, pyrimidinyl, pyridinyl, triazineyl, and the substituent is selected from at least one of the following atoms or groups: deuterium, hydroxyl, cyano, monodeuterylmethyl, dideuterylmethyl, trideuterylmethyl, C1-C4 straight-chain or branched alkyl, C6-C30 aromatic hydrocarbon group, and C5-C30 heteroaromatic hydrocarbon group.

[0011] In a preferred embodiment, Ar1 and Ar2, whether identical or different, are selected from substituted or unsubstituted phenyl, naphthyl, anthracene, phenanthrene, fluorenyl, oxofluorenyl, 9,9-spirodifluorenyl, 9,9-dimethylfluorenyl, 9,9-diphenylfluorenyl, carbazolyl, N-ethylcarbazolyl, 4-hydroxycarbazolyl, benzocarbazolyl, benzothiophene, furanyl, thiophene, phenylpyrimidinyl, pyrimidinyl, pyridinyl, triazineyl, wherein the substituents are selected from at least one of the following atoms or groups: deuterium, hydroxyl, cyano, monodeuterylmethyl, dideuterylmethyl, trideuterylmethyl, C1-C4 straight-chain or branched alkyl, C6-C30 aromatic hydrocarbon, C5-C30 heteroaromatic hydrocarbon.

[0012] Preferably, Ar1 and Ar2 are the same or different and are selected from substituted or unsubstituted phenyl, dimethylfluorenyl, dibenzofuranyl, dibenzothiophenyl, naphthyl, phenylcarbazoyl, and their substituents are selected from at least one of the following atoms or groups: deuterium, hydroxyl, cyano, monodeuterylmethyl, dideuterylmethyl, trideuterylmethyl, C6-C30 aromatic hydrocarbon group, and C5-C30 heteroaromatic hydrocarbon group.

[0013] More preferably, Ar1 and Ar2 are the same or different and are selected from substituted or unsubstituted phenyl, dimethylfluorenyl, dibenzofuranyl, dibenzothiopheneyl, naphthyl, phenylcarbazoyl, and their substituents are selected from at least one of the following atoms or groups: deuterium, hydroxyl, cyano, monodeuterylmethyl, dideuterylmethyl, trideuterylmethyl, C6-C18 aromatic hydrocarbon group, and C5-C24 heteroaromatic hydrocarbon group.

[0014] As a preferred embodiment of the present invention, the amino compound containing a deuterated fluorene group is selected from the compounds shown in Formulas 4-12:

[0015]

[0016] As a preferred embodiment of the present invention, Ar1 and Ar2 are the same or different, selected from the following groups:

[0017]

[0018] *Keys indicate keys that connect to the basic skeleton in Equations 1-3.

[0019] As a preferred embodiment of the present invention, the amine compound is one of the following structural formulas:

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033] The present invention also provides an organic electroluminescent device, which includes a first electrode, a second electrode, and an organic layer formed between the first electrode and the second electrode, wherein the organic layer contains an amine compound as described above.

[0034] In a preferred embodiment, the organic layer comprises a hole injection layer, a hole transport layer, a second hole transport layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer; at least one of the hole injection layer, hole transport layer, second hole transport layer, light-emitting layer, hole blocking layer, electron transport layer, and electron injection layer contains the aforementioned organic electroluminescent compound.

[0035] In a preferred embodiment, the second hole transport layer contains the aforementioned organic electroluminescent compound.

[0036] In a preferred embodiment, the compound of the present invention having the structure shown in Formula 1 has the following synthetic reaction route:

[0037]

[0038] The beneficial effects of this invention are:

[0039] 1. The organic electroluminescent material of the present invention introduces deuterium at specific positions in the conventional organic material of this type. The introduction of deuterium improves the chemical and thermal stability of the material and the doped material, thereby significantly improving the luminous efficiency and stability of the device.

[0040] 2. At the same time, the introduction of deuteration in this invention enables this type of compound to better match with doped materials, further improving the device's lifetime and luminous efficiency; it also improves the device's stability, thereby improving the device's luminous efficiency and lifetime. Furthermore, the introduction of deuteration can adjust the molecular weight of the material and adjust its evaporation temperature, allowing it to better match with electron-donating group materials, thus improving the device's stability and lifetime.

[0041] 3. The compounds of the present invention have a large torque, which gives them a high triplet energy level and good film-forming properties. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of the organic electroluminescent device provided by the present invention;

[0043] The numbers in the diagram represent: 1-anode, 2-hole injection layer, 3-hole transport layer, 4-second hole transport layer, 5-light-emitting layer, 6-hole blocking layer, 7-electron transport layer, 8-electron injection layer, and 9-cathode.

[0044] Figure 2 This is the HPLC chromatogram of compound 31 of the present invention.

[0045] Figure 3 This is the DSC spectrum of compound 31 of the present invention, by Figure 3 It can be seen that the Tm value of compound 31 is 215.97℃.

[0046] Figure 4 This is the TGA spectrum of compound 31 of the present invention, by Figure 4 It can be seen that the thermal weight loss temperature Td of compound 31 is 386.14℃.

[0047] Figure 5 This is the 1H NMR spectrum of compound 31 of the present invention. Detailed Implementation

[0048] The present invention can be better understood from the following embodiments. However, those skilled in the art will readily understand that the descriptions in the embodiments are for illustrative purposes only and should not, and will not, limit the invention as detailed in the claims.

[0049] Embodiments of various aspects are further illustrated and described below. It should be understood that the description herein is not intended to limit the claims to the specific aspects described. Rather, it is intended to cover substitutions, modifications, and equivalents that may be included within the spirit and scope of this disclosure as defined by the appended claims.

[0050] As used herein, in the terms “deuterated” and “undeuterated,” the term “deuterated” means that at least one hydrogen in the group is recoordinated with deuterium. The term “undeuterated” means that none of the hydrogens in the group are recoordinated with deuterium.

[0051] In this document, "aromatic group," "aryl," or "aromatic group" refers to a group containing one or more aromatic rings, including but not limited to benzene, naphthalene, phenanthrene, fluorene, acenaphthene, pyridine, pyrrole, furan, and thiophene. In C5-C40 aromatic groups, C5-C40 means that the group contains 5-40 carbon atoms. Aromatic groups can be classified as monocyclic aryl and polycyclic aryl. Specific aromatic groups in this invention include, but are not limited to, phenyl, biphenyl, terphenyl, anthracene, naphthyl, phenanthrene, fluorene, dibenzofuranyl, dibenzothiophene, 9,9-spirodifluorenyl, 9,9-dimethylfluorenyl, or 9,9-diphenylfluorenyl. Aromatic groups can be substituted or unsubstituted.

[0052] As used herein, "cycloalkyl" refers to a monocyclic or fused ring group consisting entirely of carbon atoms (a "fused" ring means that each ring in the system shares an adjacent pair of carbon atoms with other rings in the system), wherein one or more rings are saturated alicyclic rings, generally having 3-20 carbon atoms, preferably 3-12 carbon atoms, and more preferably 3-10 carbon atoms. Cycloalkyl groups can be classified into monocyclic alkyl groups having only one ring and fused alkyl groups having multiple rings. Examples of monocyclic alkyl groups include, but are not limited to, cyclopropane, cyclobutane, cyclopentane, cyclohexane, and cycloheptane. Cycloalkyl groups can be substituted or unsubstituted.

[0053] As used herein, "cycloalkenyl" refers to a monocyclic or fused ring group consisting entirely of carbon (a "fused" ring means that each ring in the system shares a pair of adjacent carbon atoms with other rings in the system), wherein one or more rings do not have a fully connected π-electron system and contain at least one alkenyl group, which generally has 3-20 carbon atoms, preferably 3-12 carbon atoms, more preferably 3-10 carbon atoms. Examples of cycloalkenyl groups include, but are not limited to, cyclopentene, cyclohexene, cyclohexadiene, and cycloheptanetriene. The cycloalkenyl group can be substituted or unsubstituted.

[0054] In this article, "deuterated aromatic group" refers to an aromatic group in which one or more hydrogen atoms are replaced by deuterium.

[0055] In this article, "deuterated phenyl" refers to a group in which one or more hydrogen atoms in a phenyl group are replaced by deuterium.

[0056] In this article, "heteroaryl" refers to a heteroaryl group obtained by replacing one or more C atoms in the structure of "aryl" with one or more heteroatoms (such as N, O or S).

[0057] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0058] Example 1

[0059] Compound 31

[0060]

[0061] Compound 31 was prepared according to the following method:

[0062] Step S1: Procedure: Add 31-SM2 (75g, 0.392mol, 1eq) and ultra-dry THF (375ml) to a 2L three-necked flask, cool to below -65℃, and add n-butyllithium (257ml, 0.412mol, 1.05eq) dropwise. After the addition is complete, keep warm and stir for 1h. Then add 31-SM1 (65.65g, 0.365mol, 0.93eq) in THF (300ml) dropwise. After the addition is complete, slowly raise to room temperature and stir overnight.

[0063] Post-processing: Stop the reaction, quench with saturated ammonium chloride aqueous solution, stir and separate the liquid, extract with DCM in aqueous phase, combine the organic phases, dry with anhydrous sodium sulfate, concentrate the filtrate to dryness under reduced pressure, and use it directly in the next reaction without purification.

[0064] Step S2: Procedure: Add 31-ZJ1 (theoretical 106.65g, 0.364mol, 1eq), triethylsilane (63.54g, 0.546mol, 1.5eq), and DCM (1000ml) to a 2L three-necked flask, cool to below 0℃, and add trifluoroacetic acid (125g, 1.092mol, 3eq) dropwise. After the addition is complete, stir the reaction overnight, and monitor the reaction by TLC until ZJ1 is almost completely eliminated.

[0065] Post-processing: Stop the reaction, add water, stir and separate the liquids, wash the organic phase with water, reduce the pressure of the organic phase, concentrate the filtrate to near dryness under reduced pressure, add 300 ml of PE, stir and slurry at 50 °C for 3 h, cool to crystallize, filter, and dry the filter cake at 60 °C with forced air to obtain 77 g of off-white solid. The overall yield of the two steps is 76.4%.

[0066] Step S3: Procedure: Add 60% sodium hydride (17.34g, 0.435mol, 3eq) and ultra-dry THF (200ml) to a 1L three-necked flask, cool to below 0℃, and add 31-ZJ2 (40g, 0.145mol, 1eq) in THF (300ml) dropwise. After the addition is complete, heat to 40℃ and stir for 1h. Then cool to below 0℃ and add deuterated iodomethane (31.43g, 0.6525mol, 1.5eq) dropwise. After the addition is complete, stir at room temperature overnight. Monitor ZJ2 ≤ 0.1% using HPLC.

[0067] Post-processing: Stop the reaction, slowly add water to quench, stir and separate the liquid, extract twice with DCM in the aqueous phase, combine the organic phases, concentrate under reduced pressure to near dryness, add 150 ml of PE and stir to crystallize, filter, dry the filter cake at 60°C with forced air to obtain 39 g of off-white solid, yield 92.9%.

[0068] Step S4: Procedure: 31-ZJ3 (29 g, 99.7 mmol, 1 eq), 31-SM4 (37.4 g, 99.7 mmol, 1 eq), sodium tert-butoxide (11.5 g, 0.12 mol, 1.2 eq), XPhos (1.9 g, 3.988 mmol, 0.04 eq), and toluene (300 ml) were added to a 1 L three-necked flask. Under N2 protection, palladium acetate (0.45 g, 1.994 mmol, 0.02 eq) was added. After the addition was complete, the temperature was raised to 100 °C and the reaction was stirred. HPLC monitoring showed that 31-ZJ3 ≤ 0.5%.

[0069] Post-processing: Stop the reaction, filter the solution hot through silica gel, concentrate the filtrate to dryness under reduced pressure, add 100 ml toluene and 400 ml ethanol, stir and slurry at 65 °C for 2 h, cool and stir to allow crystallization to occur overnight, filter, recrystallize the filter cake three times with toluene / ethanol, filter again, recrystallize the filter cake once more with toluene, filter again, and dry the filter cake at 85 °C with forced air to obtain a white solid of 17.2%, with an HPLC purity of 99.9818% and a yield of 27.4%.

[0070] Compounds 3, 7, 12, 15, 20, 23, 28, 29, 31, 37, 41, 45, 49, 53, 57, 61, 66, 69, 73, 77, 81, 85, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, 153, 157, 165, 169, 173, 177, 186, 188, 192, 194, 206, 215, 218, 223, 227, 231, 234, 285, and 286 were obtained using a similar method. See Table 1 below for details.

[0071] Table 1

[0072]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081] Example 59

[0082] Compound 238

[0083]

[0084] Compound 238 was prepared according to the following method:

[0085] Step S1: Step S2: Step S3:

[0086] Step S4: Compounds 246, 254, 262, 270, and 278 were obtained using a similar method (see Table 1 below). The compounds prepared in the table above were then synthesized and identified, and the results are shown in Table 2 below.

[0087] Table 2

[0088]

[0089]

[0090] Example 65

[0091] Compound 239

[0092]

[0093] Compound 239 was prepared according to the following method:

[0094] Step S1: Step S2: Step S3: Step S4: Compounds 247, 255, 263, 271, and 279 were obtained using a similar method, as detailed in Table 3 below.

[0095] Table 3

[0096]

[0097] Example 71 Compound 237

[0098]

[0099] Compound 237 was prepared according to the following method:

[0100] Step S1: Step S2: Step S3: Step S4: Compounds 245, 253, 261, 269, 277, 241, 249, 257, and 265 were obtained using similar methods, as detailed in Table 4 below.

[0101] Table 4

[0102]

[0103]

[0104]

[0105] The compounds prepared in Tables 1-4 above were synthesized and identified, and the results are shown in Table 5 below:

[0106] Table 5

[0107]

[0108]

[0109]

[0110]

[0111] Basic performance tests were conducted on the above materials, including thermogravimetric temperature Td and melting point Tm. The test results are shown in Table 6 below.

[0112] Note: The thermogravimetric temperature Td is the temperature at which the mass loss is 5% in a nitrogen atmosphere, measured on a TGA N-1000 thermogravimetric analyzer at a nitrogen flow rate of 10 mL / min. The melting point Tm is determined by differential scanning calorimetry (DSC, Shinco DSC N-650) at a heating rate of 10 °C / min.

[0113] Table 6

[0114]

[0115]

[0116]

[0117]

[0118]

[0119] Based on the above data, it can be seen that the compounds synthesized in this invention have excellent thermal stability, indicating that compounds conforming to the general structural formula of this invention all have excellent thermal stability and can meet the requirements for use in organic electroluminescent materials.

[0120] Device performance testing:

[0121] Application Example 1:

[0122] ITO was used as the anode substrate material for the reflective layer, and its surface was treated sequentially with water, acetone, and N2 plasma. On top of the ITO anode substrate, 10 nm of HT-1 doped with 2% NDP-9 by mass was deposited to form a hole injection layer (HIL).

[0123] A first hole transport layer (HTL) is formed by depositing 100 nm of HT-1 above the hole injection layer (HIL);

[0124] Compound 31 of the present invention was vacuum-deposited over the first hole transport layer (HTL) to form a second hole transport layer (GPL) with a thickness of 30 nm.

[0125] Compounds G1 and G2 were co-deposited as green light host materials in a 5:5 mass ratio, and GD-1 was deposited as a dopant material (GD-1 amount was 8% of the total mass of G1 and G2) on the second hole transport layer (GPL) to form a light-emitting layer with a thickness of 30 nm.

[0126] HB-1 was deposited onto the light-emitting layer to obtain a hole blocking layer (HBL) with a thickness of 20 nm;

[0127] ET-1 and LiQ were co-deposited onto the hole blocking layer (HBL) at a mass ratio of 5:5 to obtain an electron transport layer (ETL) with a thickness of 30 nm.

[0128] Magnesium (Mg) and silver (Ag) are mixed in a mass ratio of 9:1 and vapor-deposited onto the electron transport layer (ETL) to form an electron injection layer (EIL) with a thickness of 50 nm.

[0129] Subsequently, silver (Ag) is vapor-deposited onto the electron injection layer to form a cathode with a thickness of 100 nm. A 50 nm thick DNTPD is then deposited on the cathode sealing layer. Furthermore, the cathode surface is sealed with a UV-curable adhesive and a sealing cap containing a desiccant to protect the organic electroluminescent device from the influence of atmospheric oxygen or moisture. Thus, an organic electroluminescent device is prepared.

[0130]

[0131] Application Example 2-80

[0132] Compounds 3, 7, 12, 15, 20, 23, 28, 29, 37, 41, 45, 49, 53, 57, 61, 66, 69, 73, 77, 81, 85, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, 153, 157, 165, 169, 173, 177, 186, 188, and 192 from Examples 2-80 of the present invention were used respectively. 194, 206, 211, 215, 218, 223, 227, 231, 234, 285, 286, 238, 246, 254, 262, 270, 278, 239, 247, 255, 263, 271, 279, 237, 245, 253, 261, 269, 277, 241, 249, 257, and 265 were used as the second hole transport material, and the other parts were the same as in Application Example 1. Based on this, the organic electroluminescent devices of Application Examples 2-80 were fabricated.

[0133] Compare with Example 1-2:

[0134] The difference from Application Example 1 is that Compound e and Compound 11 from CN116514751A are used instead of Compound 31 in this application as the second hole transport material, while the rest is the same as Application Example 1.

[0135] The characteristics of the organic electroluminescent devices manufactured in the above application examples and the organic electroluminescent devices manufactured in the control examples were measured under a current density of 10 mA / cm2, and the results are shown in Table 7 below.

[0136] Table 7

[0137]

[0138]

[0139]

[0140]

[0141] As shown in the table above, when the compounds of the present invention are applied to organic electroluminescent devices, the luminous efficiency is significantly improved at the same current density, the device's start-up voltage is reduced, the power consumption of the device is relatively reduced, and the device's lifespan is correspondingly increased.

[0142] The organic electroluminescent devices prepared in Comparative Examples 1-2 and Application Examples 1, 2, 3, 11, 12, 19, 25, 28, 30, 46, 49, 59, 65, 71, 72, 79, and 80 were subjected to luminescence lifetime tests to obtain the luminescence lifetime T97% data (the time for the luminous brightness to decrease to 97% of the initial brightness). The testing equipment was a TEO luminescent device lifetime testing system. The results are shown in Table 8.

[0143] Table 8

[0144]

[0145]

[0146] As shown in the table above, when the compounds of this invention are applied to organic electroluminescent devices, the lifespan is significantly improved at the same current density, indicating broad application prospects.

[0147] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An amino compound containing a deuterated fluorene group, characterized in that, The amine compound is one of the following structural formulas: 。 2. An organic electroluminescent device, characterized in that, It includes a first electrode, a second electrode, and an organic layer formed between the first electrode and the second electrode, said organic layer containing an amine compound as claimed in claim 1.

3. The organic electroluminescent device according to claim 2, characterized in that, The organic layer comprises a hole injection layer, a hole transport layer, a second hole transport layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer; at least one of the hole injection layer, hole transport layer, second hole transport layer, light-emitting layer, hole blocking layer, electron transport layer, and electron injection layer contains an amino compound as described in claim 1.

4. The organic electroluminescent device according to claim 3, characterized in that, The second hole transport layer contains the amino compound as described in claim 1.

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