A phenylalkylfluorene-substituted naphthalene ring aromatic amine compound and its preparation method and application

Abstract

The invention provides a phenylalkylfluorene-substituted naphthalene ring aromatic amine compound and a preparation method and application thereof. The invention belongs to the field of organic electroluminescent materials. The phenylalkylfluorene-substituted naphthalene ring aromatic amine compound has a structure shown in Formula 1 or Formula 2. The parent nucleus of the compound of the invention is an aromatic amine and a 9-alkyl-9-phenylfluorene-based derivative group, which are ortho-substituted on the same aromatic ring of a naphthalene ring. The naphthalene ring has a strong π conjugation effect and a large delocalized area. The naphthyl group is more helpful to increase the distribution of holes in molecules and enhance the hole transport capacity of the material. The ortho-connection steric hindrance of the same aromatic ring of the naphthalene ring as shown in the invention is appropriate, so that the interaction between molecules is weakened, the molecules are not easy to crystallize, not easy to aggregate, and have good film-forming properties, and have a high glass transition temperature and thermal stability, thereby improving the service life of an OLED device. The sp 3 Hybrid functional groups can achieve improvements in efficiency.

Description

Technical Field

[0001] The invention belongs to the field of organic electroluminescent materials, and specifically relates to a phenylalkylfluorene-substituted naphthalene ring aromatic amine compound and a preparation method and application thereof. Background Art

[0002] An organic electroluminescent device (OLED) is an optoelectronic device based on the electroluminescent properties of organic materials, specifically including electrode material layers and organic functional materials sandwiched between different electrode film layers, including: hole injection layer, hole transport layer, light-emitting layer, electron transport layer and electron injection layer. In current research, in order to reduce the potential barrier between the hole transport layer and the light-emitting layer and reduce the driving voltage of the OLED, a light-emitting auxiliary layer is usually set between the two to improve the utilization of holes, thereby improving the OLED's luminous efficiency, enhancing its stability and lifespan.

[0003] In recent years, a lot of research has been conducted on light-emitting auxiliary layer materials, but few materials with excellent device performance have been found, especially in terms of improving luminous efficiency and increasing device life. Therefore, there is still a lot of room for development in the research of OLED light-emitting auxiliary materials, and finding light-emitting auxiliary materials that match the current or future OLED technology is an urgent problem that technicians in this field need to solve. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention aims to provide a luminescent auxiliary material and a preparation method and application thereof, and in particular to a phenylalkylfluorene substituted naphthalene ring aromatic amine compound and a preparation method and application thereof.

[0005] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0006] On the one hand, the present invention provides a luminescence auxiliary material having a phenylalkylfluorene-substituted naphthalene ring aromatic amine structure, wherein the luminescence auxiliary material has a structure shown in Formula 1 or Formula 2:

[0007] ;

[0008] in,

[0009] The phenyl, fluorenyl and naphthyl groups in Formula 1 and Formula 2 are undeuterated, partially deuterated or fully deuterated;

[0010] R is independently selected from unsubstituted or deuterium-substituted C1-C4 alkyl;

[0011] R1 is independently selected from hydrogen, unsubstituted or deuterium-substituted C6-C18 aryl;

[0012] Ar1 and Ar2 are independently selected from unsubstituted or C1-C5 alkyl or deuterium-substituted C6-C20 aryl, or unsubstituted or deuterium-substituted C10-C25 heteroaryl containing one heteroatom of O, S or N.

[0013] In the present invention, the C1-C4 may be C1, C2, C3 or C4, the C1-C5 may be C1, C2, C3, C4 or C5, the C6-C18 may be C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17 or C18, the C6-C20 may be C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C19 or C20, and the C10-C25 may be C10, C11, C12, C13, C14, C15, C16, C17, C18, C19, C20, C21, C22, C23, C24 or C25.

[0014] Preferably, in Formula 1 and Formula 2, R is independently selected from methyl, ethyl, isopropyl, propyl, tert-butyl or the above groups substituted with deuterium;

[0015] Preferably, R1 in Formula 1 and Formula 2 is independently selected from hydrogen, phenyl, naphthyl, biphenyl or the above groups substituted with deuterium;

[0016] Furthermore, the light-emitting auxiliary material shown in Formula 1 has any one of the following structures:

[0017]

[0018] wherein R2 is independently selected from hydrogen, unsubstituted or deuterium-substituted phenyl, and Ar1 and Ar2 are as defined above;

[0019] Preferably, Ar1 and Ar2 are independently selected from the following unsubstituted or deuterium-substituted groups:

[0020] ,

[0021] Wherein, * indicates the connection site.

[0022] In the present invention, “unsubstituted or substituted with deuterium” means substituted with one deuterium, two deuteriums, or a plurality of deuteriums, or having no substituent.

[0023] Preferably, the luminescence auxiliary material includes a compound with the following structure, but is not limited thereto:

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042]

[0043] .

[0044] Synthesis route:

[0045]

[0046] X, X1, X2, X3 are selected from Cl or Br;

[0047] R, R1, Ar1 and Ar2 have the definitions given above;

[0048] Reactant 1-1 (1.0 eq) and reactant 1-2 (1.0-1.5 eq) and potassium acetate (2.0-2.5 eq) were added to the reaction flask, followed by 1,4-dioxane, palladium catalyst (0.02-0.10 eq), phosphine ligand (0.10-0.15 eq), and the resultant was heated to 120-140°C and stirred for 8-10 hours. Celite was used for hot suction filtration, and the filtrate was cooled to room temperature, and then water was added to the filtrate for washing. After separation, the organic phase was retained, and the aqueous phase was extracted with ethyl acetate; the combined organic layer was then dried with magnesium sulfate and purified by column chromatography to obtain intermediate 1-3.

[0049] The intermediate 1-3 (1.0 eq) and the reactant 1-4 (1.0-1.5 eq) were added to the reaction flask, followed by a mixed solution of toluene, ethanol and water (volume ratio of 3:1:1), a palladium catalyst (0.01-0.03 eq), a base (2.0-3.0 eq), a phosphine ligand (0.10-0.15 eq) and cesium carbonate (2.0-3.0 eq), and the temperature was raised to 80-120 ° C, and the reaction was refluxed for 4-12 hours. The diatomaceous earth was used for hot suction filtration, and after the filtrate was cooled to room temperature, water was then added to the filtrate for washing, and the organic phase was retained after separation, and the aqueous phase was extracted with ethyl acetate; the combined organic layer was then dried with magnesium sulfate, and purified by column chromatography to obtain the intermediate 1-5.

[0050] After adding intermediate 1-5 (1.0 eq) and reactant 1-6 (1.1-1.3 eq) dissolved in xylene into a reaction vessel, palladium catalyst (0.01-0.05 eq), phosphorus ligand (0.02-0.15 eq), and base (2.0-2.4 eq) are added; after the addition, the reaction temperature is slowly raised to 130-140°C, and the mixture is stirred for 8-12 hours; diatomaceous earth is used for hot suction filtration, and after the filtrate is cooled to room temperature, distilled water is then added to the filtrate for washing, and the organic phase is retained after separation, and the aqueous phase is extracted with ethyl acetate; the combined organic layer is then dried with magnesium sulfate, and purified by column chromatography to obtain intermediate 1-7.

[0051] After adding intermediate 1-7 (1.0 eq) and reactant 1-8 (1.1-1.3 eq) dissolved in xylene into a reaction container, palladium catalyst (0.01-0.05 eq), phosphorus ligand (0.02-0.15 eq), and base (2.0-2.4 eq) are added; after the addition, the reaction temperature is slowly raised to 130-140° C., and the mixture is stirred for 8-12 hours; diatomaceous earth is used for hot suction filtration, and after the filtrate is cooled to room temperature, distilled water is then added to the filtrate for washing, and the organic phase is retained after separation, and the aqueous phase is extracted with ethyl acetate; the combined organic layer is then dried with magnesium sulfate, and purified by column chromatography to obtain formula 1.

[0052] Formula 2 can be synthesized by replacing compound 1-4 in formula 1 with compound 2-4.

[0053]

[0054] in,

[0055] X, X1, X2, X3 are selected from Cl or Br;

[0056] R, R1, Ar1 and Ar2 have the definitions given above;

[0057] The base can be: K2CO3 (potassium carbonate), K3PO4 (potassium phosphate), Na2CO3 (sodium carbonate), CsF (cesium fluoride), Cs2CO3 (cesium carbonate) or t-BuONa (sodium tert-butoxide);

[0058] The palladium catalyst may be: Pd2(dba)3 (tris(dibenzylideneacetone)dipalladium), Pd(PPh3)4 (tetrakis(triphenylphosphine)palladium), PdCl2 (palladium dichloride), PdCl2(dppf) ([1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium), Pd(OAc)2 (palladium acetate), Pd(PPh3)2Cl2 (bis(triphenylphosphine)dichloropalladium) or NiCl2(dppf) ((1,1'-bis(diphenylphosphino)ferrocene)nickel dichloride);

[0059] The phosphine ligand can be: P(t-Bu)3 (tri-tert-butylphosphine), X-phos (2-cyclohexyl-2,4,6-triisopropylbiphenyl), PET3 (triethylphosphine), PMe3 (trimethylphosphine), PPh3 (triphenylphosphine), KPPh2 (potassium diphenylphosphonate) or P(t-Bu)2Cl (di-tert-butylphosphine chloride).

[0060] On the other hand, the present invention provides an organic electroluminescent device, comprising a first electrode, a second electrode and at least one organic layer arranged between the first electrode and the second electrode, the organic layer comprising a luminescence auxiliary layer, and the material of the luminescence auxiliary layer comprises the luminescence auxiliary material described above.

[0061] The organic material layer of the organic light-emitting device of the present invention may be formed as a single-layer structure, but may also be formed as a multilayer structure having two or more organic material layers. For example, the organic light-emitting device of the present invention may have a structure including a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting auxiliary layer, a light-emitting layer, an electron transport layer, an electron injection layer, a hole blocking layer, etc. as organic material layers. However, the structure of the organic light-emitting device is not limited thereto, and may include a smaller number of organic material layers or a larger number of organic material layers.

[0062] Except that the luminescence auxiliary layer of the present invention contains the luminescence auxiliary material represented by Chemical Formula 1 or Formula 2, there is no special limitation on the materials of other layers in the OLED device.

[0063] In another aspect, the present invention provides an organic light-emitting device, comprising the organic electroluminescent device as described above.

[0064] The organic light-emitting device described in the present invention includes but is not limited to flat panel displays, computer monitors, medical monitors, televisions, billboards, lights for internal or external lighting and / or signals, head-up displays, fully transparent or partially transparent displays, flexible displays, laser printers, telephones, mobile phones, photo albums, personal digital assistants (PDAs), wearable devices, laptops, digital cameras, camcorders, viewfinders, microdisplays, three-dimensional displays, virtual reality or augmented reality displays, vehicles, video walls including multiple displays tiled together, theater or stadium screens, light therapy devices and signs, etc.

[0065] The beneficial technical effects of the present invention are:

[0066] The parent nucleus of the compound of the present invention is an aromatic amine and a 9-alkyl-9-phenylfluorenyl derivative group, which are substituted at the ortho position on the same aromatic ring of the naphthalene ring, wherein the naphthalene ring has a strong π conjugation effect and a large delocalized area, and the naphthyl group is more helpful to increase the distribution of holes in the molecule and enhance the hole transport ability of the material; the ortho-connection steric hindrance of the naphthalene ring and the aromatic ring as shown in the present invention is appropriate, so that the interaction between molecules is weakened, and the molecules are not easy to crystallize, not easy to aggregate, and have good film-forming properties, and have a high glass transition temperature and thermal stability, thereby improving the service life of the OLED device; the sp of the introduced 9-alkyl-9-phenylfluorenyl derivative is 3 Hybrid functional groups can achieve improvements in efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 It is the hydrogen nuclear magnetic resonance spectrum of compound 8 in Example 1 of the present invention. DETAILED DESCRIPTION

[0068] The technical solution of the present invention is further described below by specific implementation methods. 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] Embodiment 1:

[0070]

[0071] Reactant 8-1 (30 mmol, CAS No.: 1548450-59-4) and reactant 1-2 (40 mmol, CAS No.: 73183-34-3) and potassium acetate (65 mmol) were added to the reaction flask, followed by 1,4-dioxane, Pd(PPh3)4 (1 mmol), X-phos (3 mmol), and then the resultant was heated to 120°C and stirred for 10 hours. Celite was used for hot filtration, and after the filtrate was cooled to room temperature, water was then added to the filtrate for washing, and the organic phase was retained after separation, and the aqueous phase was extracted with ethyl acetate; the combined organic layer was then dried with magnesium sulfate and purified by column chromatography to obtain intermediate 8-3.

[0072] The intermediate 8-3 (20mmol) and the reactant 2-4 (25mmol, CAS number: 20191-75-7) were added to the reaction flask, followed by a mixed solution of toluene, ethanol, and water (volume ratio of 3:1:1), Pd(PPh3)4 (0.4mmol), Na2CO3 (45mmol), X-phos (2mmol), and cesium carbonate (50mmol), and the temperature was raised to 110°C, and the reaction was refluxed for 10 hours. The mixture was filtered while hot using diatomaceous earth, and after the filtrate was cooled to room temperature, water was then added to the filtrate for washing, and the organic phase was retained after separation, and the aqueous phase was extracted with ethyl acetate; the combined organic layer was then dried with magnesium sulfate, and purified by column chromatography to obtain the intermediate 8-5.

[0073] After adding intermediate 8-5 (20 mmol) and reactant 8-6 (50 mmol, CAS No.: 98974-71-1) and dissolving in xylene in a reaction vessel, Pd(PPh3)4 (0.5 mmol), Na2CO3 (45 mmol) and X-phos (2 mmol) were added; after the addition, the reaction temperature was slowly raised to 130°C, and the mixture was stirred for 10 hours; diatomaceous earth was used for hot suction filtration, and after the filtrate was cooled to room temperature, distilled water was then added to the filtrate for washing, and the organic phase was retained after separation, and the aqueous phase was extracted with ethyl acetate; the combined organic layer was then dried with magnesium sulfate and purified by column chromatography to obtain compound 8 (9.88 g, yield: 70.4%, test value MS (ESI, m / Z): [M+H]+=701.52).

[0074] The H NMR spectrum of compound 8 is as follows Figure 1 As shown:

[0075] Characterization:

[0076] HPLC purity: >99.8%.

[0077] Elemental Analysis:

[0078] Theoretical values: C, 92.40; H, 5.60; N, 2.00

[0079] Test values: C, 92.32; H, 5.68; N, 2.04.

[0080] Example 2-87

[0081] The following compounds were synthesized by referring to the synthesis method of Example 1 and tested using a Waters XEVO TQD mass spectrometer, which has low precision. The ESI source was used for testing, and the mass spectrometry test values ​​are shown in Table 1 below.

[0082] Table 1 Mass spectrometry test values ​​of Example 2-87

[0083]

[0084]

[0085] In addition, it should be noted that other compounds of the present invention can be obtained by referring to the synthesis methods of the above-mentioned embodiments, so they are not listed one by one here.

[0086] Device Example 1: Preparation of red organic electroluminescent device

[0087] a. ITO anode: Wash the ITO-Ag-ITO glass substrate with a coating thickness of 150nm in distilled water for 4 times, ultrasonically wash for 40 minutes, and then repeatedly wash it with distilled water for 4 times, ultrasonically wash for 20 minutes. After washing, bake it in a vacuum oven at 220℃ for 2 hours. After baking, cool it down and it can be used. Use this substrate as the anode and use the evaporation device process with an evaporation machine to evaporate other functional layers on it in sequence.

[0088] b. HIL: The hole injection layer materials HT-1 and P-dopant were vacuum evaporated at an evaporation rate of 1Å / s. The evaporation rate ratio of HT-1 to P-dopant was 97:3, and the thickness was 10nm.

[0089] c. HTL: 120 nm of HT-1 was vacuum evaporated on the hole injection layer at a deposition rate of 1.5 Å / s as the hole transport layer.

[0090] d. Prime: 80 nm of the compound 8 of the present invention was vacuum-deposited on the hole transport layer at a deposition rate of 0.5 Å / s as a light-emitting auxiliary layer.

[0091] e. EML: Then, on the above-mentioned light-emitting auxiliary layer, a main material (Host-1) and a dopant material (Dopant-1) with a thickness of 40 nm were vacuum evaporated at a deposition rate of 1Å / s as a light-emitting layer, wherein the evaporation rate ratio of Host-1 to Dopant-1 was 97:3.

[0092] f. HBL: HB-1 hole blocking layer with a thickness of 5.0 nm was vacuum-deposited at a deposition rate of 0.5 Å / s.

[0093] g. ETL: ET-1 and Liq were vacuum evaporated at a deposition rate of 1Å / s to a thickness of 30nm as the electron transport layer. The deposition rate ratio of ET-1 and Liq was 50:50.

[0094] h. EIL: 1.0 nm Yb film was evaporated at a deposition rate of 0.5 Å / s to form an electron injection layer.

[0095] i. Cathode: 13 nm of magnesium and silver were evaporated at an evaporation rate ratio of 1 Å / s, and the evaporation rate ratio was 1:9 to obtain an OLED device.

[0096] j. CPL: CPL-1 with a thickness of 65 nm was vacuum-deposited on the cathode at a deposition rate of 1 Å / s as a light extraction layer.

[0097] k. Package the substrate after evaporation. First, use the glue coating equipment to coat the cleaned cover with UV glue, then move the coated cover to the pressing section, place the evaporation-deposited substrate on the upper end of the cover, and finally bond the substrate and cover with the bonding equipment, and complete the light curing of the UV glue.

[0098] The structural formula of the compound described in the device is as follows:

[0099]

[0100] Referring to the method provided in the device embodiment 1, compounds 3, 6, 13, 24, 29, 34, 38, 46, 50, 56, 61, 65, 77, 90, 91, 92, 104, 105, 109, 145, 150, 160, 167, 180, 181, 190, 202, 215, 253, 295, 306, 307, 308, 312, 337, 340, 35 1, 358, 386, 405, 406, 415, 420, 425, 426, 427, 428, 433, 434, 438, 440, 441, 442, 444, 445, 446, 447, 455, 460, 466 and 471 are used to replace compound 8, and the light-emitting auxiliary layer is evaporated to prepare the corresponding organic electroluminescent devices, which are respectively recorded as device example 2 to device example 62.

[0101] Device Comparative Example 1-Device Comparative Example 14:

[0102] According to the above-mentioned method for preparing an organic electroluminescent device, organic electroluminescent devices of device comparative examples 1 to device comparative examples 14 were prepared, except that compound 8 in device example 1 was replaced by comparative compounds 1 to comparative compounds 14, respectively, to form a light-emitting auxiliary layer. The structural formulas of comparative compounds 1 to comparative compounds 14 are as follows:

[0103]

[0104] The driving voltage, luminous efficiency and life of the organic electroluminescent devices obtained from the above device examples 1 to device example 62 and device comparative examples 1 to device comparative examples 14 were characterized at a brightness of 6000 (nits). The test results are shown in Table 2 below:

[0105] Table 2

[0106]

[0107]

[0108]

[0109]

[0110]

[0111] Device Example 63: Preparation of Green Organic Electroluminescent Device

[0112] a. Wash the ITO-Ag-ITO glass substrate with a coating thickness of 150nm in distilled water for 4 times, ultrasonically wash for 40 minutes, and then repeatedly wash it with distilled water for 4 times, ultrasonically wash for 20 minutes. After washing, bake it in a vacuum oven at 220℃ for 2 hours. After baking, cool it down and it can be used. Use the substrate as the anode and use the evaporation device process with the evaporation machine to evaporate other functional layers on it in sequence.

[0113] b. HIL: The hole injection layer materials HT-2 and P-dopant were vacuum evaporated at a deposition rate of 1 Å / s. The deposition rate ratio of HT-2 to P-dopant was 97:3, and the thickness was 10 nm.

[0114] c. HTL: 130 nm of HT-2 was vacuum-deposited on the hole injection layer at a deposition rate of 1.5 Å / s as the hole transport layer.

[0115] d. Prime: 40 nm of the compound 8 of the present invention was vacuum-deposited on the hole transport layer at a deposition rate of 0.5 Å / s as a light-emitting auxiliary layer.

[0116] e. EML: Then, on the above-mentioned light-emitting auxiliary layer, a dual host material (Host-2 and Host-3) and a dopant material (Dopant-2) with a thickness of 30nm were vacuum-deposited at a deposition rate of 1Å / s as a light-emitting layer, where Host-2 and Host-3 were 50:50. The deposition rate ratio of the dual host material and Dopant-2 was 90:10.

[0117] f. HBL: HB-2 hole blocking layer with a thickness of 5.0 nm was vacuum evaporated at a deposition rate of 0.5 Å / s.

[0118] g. ETL: ET-2 and Liq were vacuum evaporated at a deposition rate of 1Å / s to a thickness of 30nm as the electron transport layer. The deposition rate ratio of ET-2 and Liq was 50:50.

[0119] h. EIL: 1.0 nm Yb film was evaporated at a deposition rate of 0.5 Å / s to form an electron injection layer.

[0120] i. Cathode: 13 nm of magnesium and silver were evaporated at an evaporation rate ratio of 1 Å / s, and the evaporation rate ratio was 1:9 to obtain an OLED device.

[0121] j. CPL: CPL-2 with a thickness of 65 nm was vacuum-deposited on the cathode at a deposition rate of 1 Å / s as a light extraction layer.

[0122] k. Package the substrate after evaporation. First, use the glue coating equipment to coat the cleaned cover with UV glue, then move the coated cover to the pressing section, place the evaporation-deposited substrate on the upper end of the cover, and finally bond the substrate and cover with the bonding equipment, and complete the light curing of the UV glue.

[0123] The structural formula of the compound described in the device is as follows:

[0124]

[0125] Referring to the method provided in the above device embodiment 63, compounds 6, 9, 13, 15, 26, 29, 30, 37, 56, 61, 65, 70, 79, 81, 90, 91, 92, 105, 125, 135, 145, 150, 180, 181, 195, 197, 209, 223, 246, 267, 302, 307, 308, 312, 337, 340, 354 are selected respectively. , 358, 405, 413, 414, 415, 420, 426, 427, 428, 433, 434, 438, 440, 441, 442, 443, 444, 445, 446, 449, 455, 456, 461 and 468 are used to replace compound 8, and the light-emitting auxiliary layer is evaporated to prepare the corresponding organic electroluminescent devices, which are respectively recorded as device example 63 to device example 124.

[0126] Device Comparative Example 15-Device Comparative Example 28:

[0127] According to the above-mentioned method for preparing an organic electroluminescent device, organic electroluminescent devices of device comparative examples 15 to device comparative examples 28 were prepared, except that compound 8 in device example 63 was replaced by comparative compound 1 to comparative compound 14 to form a light-emitting auxiliary layer. The structural formulas of comparative compound 1 to comparative compound 14 are as shown above:

[0128] The driving voltage, luminous efficiency and life of the organic electroluminescent devices obtained from the above device examples 63 to 124 and device comparative examples 15 to 28 were characterized at a brightness of 15000 (nits). The test results are shown in Table 3 below:

[0129] Table 3

[0130]

[0131]

[0132]

[0133] It can be seen from Table 2 and Table 3 that the compounds conforming to the general formula of the present invention have excellent performance in terms of luminous efficiency and lifespan, and the driving voltage is also lower than that of the comparative compounds.

[0134] Among them, comparative compound 2 and comparative compound 3 are parallel comparative examples with compounds 426 and 427 of the present invention, respectively, and the only difference is whether the naphthalene ring is substituted by a methyl group. It can be seen from the device data that the overall structural performance without a methyl group is better. The reason may be that the presence of a methyl group affects the thermal stability of the material, increases the risk of thermal decomposition, and is not conducive to the life of the device, or the methyl group with smaller steric hindrance does not increase the steric hindrance while enhancing the interaction between molecules, thereby reducing the hole migration ability of the material and resulting in lower luminescence efficiency.

[0135] Comparative Compound 4 and Compound 415, Comparative Compound 5 and Compound 105, Comparative Compound 6 and Compound 440, and Comparative Compound 7 and Compound 307 are parallel comparative examples, and the only difference is the bonding position of 9-methyl-9-phenylfluorenyl and aromatic amine on the naphthalene ring. From the device results, it can be seen that when the two groups are connected in the ortho position as in the present invention, it is more conducive to achieving a long life of the device. The reason is that the degree of increase in the steric hindrance of the ortho position connection is appropriate, which weakens the intermolecular interaction, has the characteristics of being difficult to crystallize and aggregate between molecules, and has good film-forming properties, has a high glass transition temperature and thermal stability, and improves the service life of the OLED device.

[0136] Comparative compound 9 and compound 414 are parallel comparative examples, and the only difference is the connecting group between the 9-ethyl-9-phenyl group and the aromatic amine group. The connecting group in the comparative compound is a phenylene group, and the connecting group in the present invention is a naphthyl group. From the device data, it can be seen that the device performance of the compounds conforming to the general formula of the present invention is excellent overall. The reason is that compared with the phenylene group, the naphthyl group has a stronger π conjugation effect and a larger delocalized area. The naphthyl group is more helpful to increase the distribution of holes in the molecule and enhance the hole transport ability of the material.

[0137] Comparative compound 14 and compound 340 are parallel comparative examples, the only difference being that they have a different connecting group on the aromatic amine, a spirocyclic group in the comparative compound and a 9,9-dimethylfluorenyl group in the compound of the present invention. When the two compounds are compared, the spirocyclic group has a larger molecular weight, which results in a higher rise in the evaporation temperature, which is detrimental to thermal stability and affects the device life.

[0138] The applicant declares that the present invention uses the above-mentioned embodiments to illustrate the luminescent auxiliary material and its preparation method and application, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the raw materials selected by 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 luminescent auxiliary material, characterized in that: The light-emitting auxiliary material has a structure as shown in Formula 1 or Formula 2: ； in, The phenyl, fluorenyl and naphthyl groups in Formula 1 and Formula 2 are undeuterated, partially deuterated or fully deuterated; R is independently selected from unsubstituted or deuterium-substituted C1-C4 alkyl; R1 is independently selected from hydrogen, unsubstituted or deuterium-substituted C6-C18 aryl; Ar1 and Ar2 are independently selected from unsubstituted or C1-C5 alkyl or deuterium-substituted C6-C20 aryl, or unsubstituted or deuterium-substituted C10-C25 heteroaryl containing one heteroatom of O, S or N.

2. The luminescence auxiliary material according to claim 1, characterized in that: In Formula 1 and Formula 2, R is independently selected from methyl, ethyl, isopropyl, propyl, tert-butyl or the above groups substituted by deuterium.

3. The luminescence auxiliary material according to claim 1, characterized in that: In Formula 1 and Formula 2, R1 is independently selected from hydrogen, phenyl, naphthyl, biphenyl or the above groups substituted by deuterium.

4. The luminescence auxiliary material according to claim 1, characterized in that: The light-emitting auxiliary material shown in Formula 1 has any one of the following structures: ； wherein R2 is independently selected from hydrogen, unsubstituted or deuterium-substituted phenyl.

5. The luminescence auxiliary material according to claim 1, characterized in that: Ar1 and Ar2 are independently selected from the following unsubstituted or deuterium-substituted groups: ， Wherein, * indicates the connection site.

6. The luminescence auxiliary material according to claim 1, characterized in that: The luminescence auxiliary material includes a compound with the following structure: 。 7. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises a first electrode, a second electrode and at least one organic layer disposed between the first electrode and the second electrode, the organic layer comprises a luminescence auxiliary layer, and the material of the luminescence auxiliary layer comprises the luminescence auxiliary material according to any one of claims 1 to 6.

8. The organic electroluminescent device according to claim 7, characterized in that: The organic layer further includes at least one of a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, an electron transport layer, an electron injection layer or a hole blocking layer.

9. An organic light-emitting device, characterized in that: The organic light-emitting device comprises the organic electroluminescent device according to claim 7 or 8.

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