A kind of luminescence auxiliary material and its preparation method and application

Abstract

This invention belongs to the field of organic electroluminescence and discloses a luminescent auxiliary material, its preparation method, and its application. The structure of the luminescent auxiliary material is shown in chemical formula I. The luminescent auxiliary material compound provided by this invention uses a benzonaphthofuran group and a triarylamine group bridged by a naphthyl group as the parent core. The rigid benzonaphthofuran structure can effectively enhance structural stability, and the presence of the triarylamine group can improve the hole transport efficiency of the material. Furthermore, bridging the two main structures with a naphthyl group can form a more efficient conjugated system, improving the electron mobility of the entire material, enabling the device to have high luminescent efficiency, long service life, and maintain a low driving voltage.

Description

Technical Field

[0001] The invention belongs to the field of organic electroluminescence and relates to a luminescence auxiliary material and a preparation method and application thereof. Background Art

[0002] An organic electroluminescent device (OLED) converts electrical energy into light by applying power to an organic electroluminescent material, and generally comprises an anode, a cathode, and an organic layer formed between the two electrodes. The organic layer of an OLED may comprise a hole injection layer, a hole transport layer, a hole auxiliary layer, a light-emitting auxiliary layer, an electron blocking layer, a light-emitting layer (containing a host and a dopant material), an electron buffer layer, a hole blocking layer, an electron transport layer, an electron injection layer, and the like.

[0003] In order to solve the problems of lifespan and efficiency, a luminescent auxiliary layer is usually added between the hole transport layer and the light-emitting layer. The luminescent auxiliary layer mainly plays the role of assisting the hole transport layer, so it is sometimes also called the second hole transport layer. The luminescent auxiliary layer can enable the holes transferred from the anode to move smoothly to the light-emitting layer, and can block the electrons transferred from the cathode to confine the electrons in the light-emitting layer, reduce the potential barrier between the hole transport layer and the light-emitting layer, reduce the driving voltage of the organic electroluminescent device, and further increase the utilization rate of holes, thereby improving the luminous efficiency and life of the device.

[0004] Materials with hole transport properties mainly include hydrazones, carbazoles, oxadiazoles, triarylamines, styrenes and butadiene compounds. Among them, triarylamine materials can form ammonium ion radicals under the action of an electric field, have high hole mobility, and have good photoelectric properties. Triarylamine compounds are centered on nitrogen atoms and connected to three substituents, with a propeller-like structure. The large steric hindrance and hyperconjugation effect make the nitrogen atom radicals have high stability. This unique free radical property makes this type of compound have a high hole mobility.

[0005] However, there are currently few materials that can be used as light-emitting auxiliary layers and have excellent device performance. In particular, the device life and luminous efficiency are not significantly improved. Therefore, how to develop a light-emitting auxiliary material with high luminous efficiency, long service life and low driving voltage has always been a problem that technicians in this field need to solve urgently. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention discloses a luminescent auxiliary material and a preparation method and application thereof.

[0007] It should be noted that the light-emitting auxiliary material structure disclosed in the present invention is based on a benzonaphthofuran group and a triarylamine group connected by a naphthyl bridge as the parent core body. The rigid benzonaphthofuran structure can effectively enhance the structural stability. The presence of the triarylamine group can improve the hole transport efficiency of the material. Further bridging the naphthyl group between the two main structures can form a more efficient conjugated system, thereby improving the electron mobility of the entire material, so that the device has high luminous efficiency and long service life while maintaining a low driving voltage.

[0008] In order to achieve the above-mentioned object, the first object of the present invention is to provide a luminescent auxiliary material, which adopts the following technical solution:

[0009] A luminescence auxiliary material, the general structural formula of the luminescence auxiliary material is shown in Chemical Formula I:

[0010] ;

[0011] in,

[0012] and They are connected to a benzene ring of naphthalene. The connection position of the two can be selected from 1 or 2, and the two are connected in the ortho position. The connection position of the naphthalene group is as follows: ;

[0013] R1 is selected from hydrogen, substituted or unsubstituted C6-C12 aryl;

[0014] Ar1 and Ar2 are independently selected from substituted or unsubstituted C6-C30 aryl groups and substituted or unsubstituted C5-C30 heteroaryl groups; and their heteroatoms contain at least one of O, S, N, Si and Se.

[0015] Further, the chemical formula I has the structure of the following chemical formulas IA to IB:

[0016] .

[0017] Furthermore, R1 is selected from hydrogen, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl.

[0018] Furthermore, Ar1 and Ar2 are independently selected from the following structures:

[0019] ;

[0020] in,

[0021] R2-R 13 Each is independently selected from hydrogen, deuterium, deuterium-substituted or unsubstituted C1-C6 alkyl;

[0022] n2、n 10 are independently selected from integers from 1 to 5;

[0023] n3 and n7 are independently selected from integers from 1 to 9;

[0024] n4, n5, n 12 are independently selected from integers from 1 to 13;

[0025] n6 and n8 are independently selected from integers from 1 to 7;

[0026] n9 is independently selected from an integer from 1 to 8;

[0027] n 11 、n 13 are independently selected from integers from 1 to 11.

[0028] It should be noted that the "substituted" in the substituted or unsubstituted group is selected from deuterium, halogen, cyano, TMS, trifluoromethyl, methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, pentyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, 1-methylhexyl, cyclopentane, cyclohexane, phenyl, biphenyl The invention may be substituted by: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 68, 70, 69, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92

[0029] In the above technical solution, the light-emitting auxiliary material is any one of the following structures, but is not limited thereto: .

[0030] The second object of the present invention is to provide a method for preparing the luminescence auxiliary material as described above.

[0031] It should be noted that the luminescence auxiliary material in the present invention can be prepared by methods known to those skilled in the art. Alternatively, the following reaction process is preferred for preparation, and the specific operation is as follows:

[0032] (1) Add raw material A (1.0 eq), raw material B (1.0-1.3 eq), potassium carbonate (2.0-4.0 eq) and a mixed solution of toluene, ethanol and water (V:V:V=3:1:1) into a three-necked flask, add tetrakis(triphenylphosphine)palladium (0.01-0.03 eq) under nitrogen protection, then heat to 75-95°C and stir to react for 1-14 hours; detect the reaction by thin layer chromatography to confirm the completion of the reaction, cool down, add water and dichloromethane for extraction and separation, combine the organic phases and concentrate, and purify by column chromatography using a mixed solution of dichloromethane and petroleum ether (1:3-1:10) to obtain intermediate 1;

[0033] (2) Add intermediate 1 (1.0-1.3 eq), raw material C (1.0 eq), sodium tert-butoxide (2.0-4.0 eq) and toluene into a three-necked flask, add tri(dibenzylideneacetone)dipalladium (0.01-0.05 eq) and tri-tert-butylphosphine (0.01-0.10 eq) under nitrogen protection, then heat to 110-120° C. and stir to react for 4-24 h; detect the reaction by thin layer chromatography to confirm the completion of the reaction, cool down, add water and dichloromethane for extraction and separation, combine the organic phases and concentrate, and purify by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V=1:4-1:12) to obtain chemical formula I;

[0034] The specific synthetic route is as follows:

[0035] ;

[0036] In the above formula, Ar1, Ar2, R1 are as defined in the above chemical formula I, and X independently represents or , where * is the attachment site.

[0037] In particular, for complex raw materials that have not been disclosed before, the classic Suzuki coupling reaction and Buchwald-Hartwig coupling reaction are used for synthesis and applied to the present invention.

[0038] The third object of the present invention is to provide an application of a luminescence auxiliary material, wherein the luminescence auxiliary material as described above is applied to an organic electroluminescent device.

[0039] Specifically, the organic electroluminescent device includes a first electrode, a second electrode, and at least one organic layer disposed between the first electrode and the second electrode.

[0040] It should be noted that the organic material layer of the organic electroluminescent device in the present invention can be formed as a single-layer structure or a multilayer structure having two or more organic material layers. For example, the organic electroluminescent device 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.

[0041] Specifically, except that the light-emitting auxiliary layer of the present invention contains chemical formula I, there is no special limitation on the materials of other layers in the OLED device.

[0042] Further, the organic electroluminescent device can be used in an organic electroluminescent device, which includes but is not limited to a flat panel display, a computer monitor, a medical monitor, a television, a billboard, a lamp for internal or external lighting and / or signaling, a head-up display, a fully transparent or partially transparent display, a flexible display, a laser printer, a telephone, a mobile phone, a tablet, a photo album, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a video camera, a viewfinder, a microdisplay, a three-dimensional display, a virtual reality or augmented reality display, a vehicle, a video wall including multiple displays tiled together, a theater or venue screen, a light therapy device and a sign.

[0043] Compared with the prior art, the present invention provides a luminescent auxiliary material and a preparation method and application thereof, which have the following excellent effects:

[0044] The material compound disclosed in the present invention has a benzonaphthofuran group and a triarylamine group connected by a naphthyl bridge as a parent core main structure. As a luminescent auxiliary layer material, the device has high thermal stability, high luminous efficiency and long service life, while maintaining a low driving voltage.

[0045] Specifically, 1) the benzonaphthofuran group itself has strong rigidity, which can effectively improve the electrochemical stability and thermal stability of the overall structure, making the material less likely to undergo structural changes at high temperatures, thereby effectively improving the service life of the device;

[0046] 2) Due to the presence of nitrogen atoms containing lone pairs of electrons in triarylamine, the electrons on the nitrogen atoms are transferred by transition under the action of an external electric field, so that holes are generated in the molecule, thereby realizing the reverse transfer of holes; and the triarylamine group itself has hole transport properties, which is conducive to the efficient transfer of holes from the anode to the light-emitting layer, and reduces the energy loss during the hole transfer process. Further connecting a group that matches its energy level to the triarylamine structure is to add a geometric structure to the non-planar molecular structure to form a compound with a larger spatial configuration, which is more conducive to the transfer of holes, obtains better hole transfer efficiency, and thus improves the luminescence efficiency of the device;

[0047] 3) A bridging naphthylene group is introduced between the benzonaphthofuran group and the triarylamine. The two are connected at the ortho position on the same benzene ring of the naphthylene group. This connection method can effectively increase the packing density of the molecule, which is beneficial to the transfer of charge. It can form a longer and more effective conjugated system with it, improve the electron mobility of the entire material, and thus help to improve the luminous efficiency of the device. The rigidity of the naphthylene group helps to arrange the molecules in an orderly manner, adjust the energy level of the entire molecule, balance the transfer of electrons and holes, ensure the charge balance in the device, and improve the thermal stability of the molecule, making the material less likely to undergo structural changes and cracking during high-temperature evaporation, thereby increasing the service life of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0049] Figure 1 is the H NMR spectrum of compound 1. DETAILED DESCRIPTION

[0050] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention and the related drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] The invention specifically discloses a luminescent auxiliary material and a preparation method and application thereof.

[0052] It should be noted that the numerical values ​​given in the following examples are as accurate as possible, but due to inevitable measurement errors and experimental operation problems of those skilled in the art, each number should be understood as an approximate number rather than an absolutely accurate value.

[0053] The specific embodiments described below are only part of the embodiments of the present application, rather than all the embodiments.

[0054] The features and performance of the present invention will be further described in detail below with reference to the embodiments.

[0055] Example 1

[0056] ;

[0057] Step 1 specifically includes the following processes:

[0058] Raw material A-1 (1.0 eq, CAS number: 1256544-28-1), raw material B-1 (1.1 eq, CAS number: 71436-66-3), potassium carbonate (3.0 eq) and a mixed solution of toluene, ethanol and water (V:V:V=3:1:1) were added to a three-necked flask, and tetrakis(triphenylphosphine)palladium (0.01 eq) was added under nitrogen protection, and then the temperature was raised to 95°C and stirred for reaction for 6 hours; the reaction was detected by thin layer chromatography to confirm the completion of the reaction, the temperature was lowered, water and dichloromethane were added for extraction and separation, the organic phases were combined and concentrated, and the intermediate 1 was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V=1:5) to obtain intermediate 1 (yield: 77.6%).

[0059] Step 2 specifically includes the following processes:

[0060] Intermediate 1 (1.0 eq), raw material C-1 (1.0 eq, CAS number: 1421789-16-3), sodium tert-butoxide (2.0 eq) and toluene were added into a three-necked flask, and tri(dibenzylideneacetone)dipalladium (0.03 eq) and tri-tert-butylphosphine (0.05 eq) were added under nitrogen protection, and then the temperature was raised to 120°C and stirred for reaction for 15 hours; the reaction was detected by thin layer chromatography to confirm that the reaction was completed, the temperature was lowered, water and dichloromethane were added for extraction and separation, the organic phases were combined and concentrated, and a mixed solution of dichloromethane and petroleum ether (V:V=1:6) was used for purification by column chromatography to obtain compound 1 (yield: 82.7%).

[0061] The obtained compound 1 was tested and analyzed, and the results were as follows:

[0062] HPLC purity: >99.8%.

[0063] Mass spectrometry test: The model is Waters XEVO TQD mass spectrometer, using ESI source.

[0064] Test value MS (ESI, m / Z): [M+H] + =703.54.

[0065] Elemental Analysis:

[0066] Calculated values: C, 90.44; H, 5.30; N, 1.99; O, 2.27;

[0067] Test values: C, 90.12; H, 5.44; N, 2.12; O, 2.43.

[0068] H NMR spectrum: Figure 1 (Compound 1) shown.

[0069] Example 2

[0070] ;

[0071] Step 1 specifically includes the following processes:

[0072] Raw material A-163 (1.0 eq, CAS number: 2007912-86-7), raw material B-163 (1.1 eq, CAS number: 692728-68-0), potassium carbonate (3.0 eq) and a mixed solution of toluene, ethanol and water (V:V:V=3:1:1) were added into a three-necked flask, and tetrakis(triphenylphosphine)palladium (0.01 eq) was added under nitrogen protection, and then the temperature was raised to 95°C and stirred for reaction for 7 hours; the reaction was detected by thin layer chromatography to confirm the completion of the reaction, the temperature was lowered, water and dichloromethane were added for extraction and separation, the organic phases were combined and concentrated, and the intermediate 1 was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V=1:6) to obtain intermediate 1 (yield: 76.3%).

[0073] Step 2 specifically includes the following processes:

[0074] Intermediate 1 (1.0 eq), raw material C-163 (1.0 eq, CAS number: 897921-58-3), sodium tert-butoxide (2.0 eq) and toluene were added into a three-necked flask, and tri(dibenzylideneacetone)dipalladium (0.03 eq) and tri-tert-butylphosphine (0.05 eq) were added under nitrogen protection, and then the temperature was raised to 120°C and stirred for reaction for 18 hours; the reaction was detected by thin layer chromatography to confirm the completion of the reaction, the temperature was lowered, water and dichloromethane were added for extraction and separation, the organic phases were combined and concentrated, and a mixed solution of dichloromethane and petroleum ether (V:V=1:6) was used for purification by column chromatography to obtain compound 163 (yield: 81.8%).

[0075] The obtained compound 163 was tested and analyzed, and the results were as follows:

[0076] HPLC purity: >99.7%.

[0077] Mass spectrometry test: The model is Waters XEVO TQD mass spectrometer, using ESI source.

[0078] Test value MS (ESI, m / Z): [M+H] + =687.51.

[0079] Elemental Analysis:

[0080] Calculated values: C, 90.80; H, 4.84; N, 2.04; O, 2.33;

[0081] Analytical values: C, 90.45; H, 4.99; N, 2.18; O, 2.47.

[0082] Example 3-47

[0083] The following compounds were synthesized by referring to the preparation methods of Examples 1 to 2 and tested using a Waters XEVOTQD mass spectrometer with low precision. The ESI source was used for testing and the mass spectrometry test values ​​are shown in Table 1 below.

[0084] Table 1 Mass spectrometry test values ​​of Examples 3-47

[0085]

[0086] In addition, it should be noted that other compounds of the present invention can be obtained by referring to the preparation methods of the above-mentioned embodiments, so they are not listed one by one here.

[0087] The organic electroluminescent device provided by the present invention is described below in conjunction with specific embodiments.

[0088] Device Example 1: Preparation of Blue Light Organic Electroluminescent Device

[0089] The structure of the prepared OLED device is: ITO anode / HIL / HTL / Prime / EML / HBL / ETL / EIL / cathode / CPL.

[0090] a. ITO anode: The ITO (indium tin oxide)-Ag-ITO (indium tin oxide) glass substrate with a coating thickness of 1500Å was cleaned in distilled water for 3 times, ultrasonically washed for 40 minutes, and then repeatedly cleaned with distilled water for 3 times, ultrasonically washed for 20 minutes. After washing, it was ultrasonically washed with methanol, acetone, and isopropanol in sequence (5 minutes each time), dried, and then transferred to a plasma cleaning machine for washing for 5 minutes. It was then sent to a vapor deposition machine, and the substrate was used as the anode, and other functional layers were deposited on it in sequence.

[0091] b. HIL (hole injection layer): Hole injection layer materials HT and P-dopant were vacuum evaporated at a deposition rate of 1Å / s. The chemical formula of the materials is shown below. The deposition rate ratio of HT and P-dopant was 97:3, and the thickness was 10nm.

[0092] c. HTL (hole transport layer): HT with a thickness of 125 nm was vacuum-deposited on the hole injection layer at a deposition rate of 1.5 Å / s as the hole transport layer.

[0093] d. Prime (luminescence auxiliary layer): Compound 1 provided in the above embodiment is vacuum-deposited on the hole transport layer with a thickness of 5 nm at a evaporation rate of 0.5 Å / s as a luminescence auxiliary layer.

[0094] e. EML (light-emitting layer): At a deposition rate of 1Å / s, a host material (Host) and a dopant material (Dopant) with a thickness of 25nm are vacuum-deposited on the light-emitting auxiliary layer as the light-emitting layer. The chemical formulas of Host and Dopant are shown below. The deposition rate ratio of Host and Dopant is 98:2.

[0095] f. HBL (hole blocking layer): A hole blocking layer HB with a thickness of 5 nm was vacuum-deposited on the light-emitting layer at a deposition rate of 0.5 Å / s.

[0096] g. ETL (electron transport layer): ET and Liq with a thickness of 30 nm were vacuum-deposited on the hole blocking layer at a deposition rate of 1 Å / s as an electron transport layer. The chemical formula of ET is shown below, where the deposition rate ratio of ET and Liq is 50:50.

[0097] h. EIL (electron injection layer): A Yb film with a thickness of 1 nm is vacuum-deposited on the electron transport layer at a deposition rate of 0.5 Å / s to form an electron injection layer.

[0098] i. Cathode: Magnesium and silver with a thickness of 13 nm were vacuum evaporated on the electron injection layer at a deposition rate of 1Å / s. The deposition rate ratio of magnesium to silver was 1:9 to obtain a cathode.

[0099] j. CPL (light extraction layer): CPL with a thickness of 60 nm is vacuum-deposited on the cathode at a deposition rate of 1Å / s as a light extraction layer.

[0100] k. Package the vapor-deposited substrate: 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 vapor-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 at the same time.

[0101] The structures of HT, P-dopant, Host, Dopant, HB, ET, and CPL used in the device embodiment 1 are as follows:

[0102] .

[0103] Device Example 2-47:

[0104] Referring to the method provided in the above device embodiment 1, the corresponding compounds in Table 2 were selected to replace compound 1, and the luminescent auxiliary layer was evaporated to prepare the corresponding organic electroluminescent devices, which were respectively recorded as device embodiments 2-47.

[0105] Device Comparison Examples 1-11:

[0106] The comparative example provides an organic electroluminescent device, the preparation method of which is different from that of the device embodiment 1 in that the organic electroluminescent device uses the existing compound ak to replace the luminescent auxiliary material (compound 1) in the device embodiment 1 for evaporation. The chemical structure of the compound ak is as follows:

[0107] .

[0108] The driving voltage, luminous efficiency and life of the organic electroluminescent devices obtained from the device embodiments 1-47 and the device comparative examples 1-11 were characterized at a brightness of 1000 (nits). The test results are shown in Table 2 below:

[0109] Table 2 Device test results

[0110]

[0111] Those skilled in the art will know that in a blue top-emitting device, the luminous efficiency is greatly affected by chromaticity. Therefore, the influence of chromaticity on efficiency is taken into account, and the ratio of luminous efficiency to CIEy is defined as the BI value, that is, BI = (cd / A) / CIEy.

[0112] It can be seen from Table 2 that, compared with the organic electroluminescent device prepared using the luminescent auxiliary material provided by the present invention and the organic electroluminescent device prepared using the comparative example compound, the luminescent efficiency and service life of the device are effectively improved while maintaining a lower driving voltage.

[0113]

[0114] Compounds a, b and compounds 207, 6 are parallel comparative examples, respectively, and the difference between them is that the triarylamine in compounds a and b is connected to a dibenzofuran group through a bridging naphthyl group, while the triarylamine in compounds 207 and 6 of the present invention is connected to a benzonaphthofuran group through a bridging naphthyl group. The addition of an additional benzene ring to the dibenzofuran group effectively increases the conjugated area of ​​the overall structure, effectively improves the luminous efficiency of the device, and at the same time enhances the rigidity of the compound, so that the film-forming property and stability of the material during the evaporation process are better, thereby increasing the service life of the device.

[0115]

[0116] Compounds c, d and compounds 121, 67 are parallel comparative examples, respectively, and the difference between them is that the triarylamine in compounds c and d is directly connected to the benzonaphthofuran group, while the triarylamine and the benzonaphthofuran group in compounds 121 and 67 of the present invention are connected by a bridging naphthyl group, which can effectively extend the conjugation length of the entire molecule, avoid localization of carrier migration, and regulate the energy level of the molecule, enhance the hole transport performance, and help to improve the luminous efficiency and brightness of the device; in addition, the introduction of the naphthyl group can improve the thermal stability of the material, so that it can still maintain the performance of the material at high temperature, which helps to improve the service life of the device.

[0117]

[0118] Compounds e and f and compounds 93 and 134 are parallel comparative examples, and the difference between them is that in compounds e and f, the triarylamine and benzonaphthofuran groups are connected by phenylene and biphenylene, respectively, while in compounds 93 and 134 of the present invention, the triarylamine and benzonaphthofuran groups are connected by naphthylene. The naphthylene has better rigidity, which enables the material to maintain structural stability during high-temperature evaporation and is not easily degraded, thereby effectively improving the life of the device.

[0119]

[0120] Compound g and compound 31 are parallel comparative examples, the difference between them is that the ring-bonding position of the benzonaphthofuran group in compound g is at the 3 and 4 positions of furan, while the ring-bonding position of the benzonaphthofuran group in compound 31 of the present invention is at the 1 and 2 positions of furan. The ring-bonding at this position makes the conjugation between the benzene ring and dibenzofuran more continuous, forming a larger conjugated system with a higher fluorescence quantum yield, which helps to improve the luminescence efficiency of the device.

[0121]

[0122] Compound h and compound 212 are parallel comparative examples, the difference between them being that the triarylamine and benzonaphthofuran groups in compound h are respectively connected to different benzene rings of the naphthyl group serving as a bridging group in the middle, while compound 212 of the present invention is connected to the same benzene ring of the naphthyl group, and is connected in the ortho position (positions 1 and 2 of the naphthyl group), making the overall structure of the molecule more tightly and orderly stacked, thereby improving the stability of the material and thus improving the life of the device.

[0123] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A luminescent auxiliary material, characterized in that: The general structural formula of the luminescence auxiliary material is shown in Chemical Formula I: ； in, and The two are connected to a benzene ring of naphthalene, the positions of the two connections are selected from 1 or 2, and the two are connected at the ortho position; R1 is selected from hydrogen, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, wherein the "substituted" in the substituted or unsubstituted is selected from deuterium; Ar1 and Ar2 are independently selected from the following structures: ； in, R2-R 13 Each is independently selected from hydrogen, deuterium, deuterium-substituted or unsubstituted C1-C6 alkyl; n2、n 10 are independently selected from integers from 1 to 5; n3 and n7 are independently selected from integers from 1 to 9; n4, n5, n 12 are independently selected from integers from 1 to 13; n6 and n8 are independently selected from integers from 1 to 7; n9 is independently selected from an integer from 1 to 8; n 11 、n 13 are independently selected from integers from 1 to 11.

2. The luminescence auxiliary material according to claim 1, characterized in that: The structure of the luminescence auxiliary material is selected from any one of the following compounds: .

3. A method for preparing the luminescence auxiliary material according to claim 1, characterized in that: The method specifically comprises the following steps: (1) 1.0 eq of raw material A, 1.0-1.3 eq of raw material B, 2.0-4.0 eq of potassium carbonate and a mixed solution of toluene, ethanol and water in a volume ratio of 3:1:1 were added to a three-necked flask, and 0.01-0.03 eq of tetrakis(triphenylphosphine)palladium was added under nitrogen protection, and then the temperature was raised to 75-95° C. and stirred for reaction for 1-14 hours; the reaction was detected by thin layer chromatography to confirm the completion of the reaction, and the temperature was lowered, and water and dichloromethane were added for extraction and separation. The organic phases were combined and concentrated, and the intermediate 1 was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:3-1:10; (2) 1.0-1.3 eq of intermediate 1, 1.0 eq of raw material C, 2.0-4.0 eq of sodium tert-butoxide and toluene are added to a three-necked flask, and 0.01-0.05 eq of tris(dibenzylideneacetone)dipalladium and 0.01-0.10 eq of tri-tert-butylphosphine are added under nitrogen protection, and then the temperature is raised to 110-120° C. and stirred for reaction for 4-24 hours; the reaction is detected by thin layer chromatography to confirm that the reaction is complete, the temperature is lowered, water and dichloromethane are added for extraction and separation, the organic phases are combined and concentrated, and a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:4-1:12 is used to purify by column chromatography to obtain chemical formula I; The specific synthetic route is as follows: ； Wherein, Ar1, Ar2, R1 are as defined in the chemical formula I of claim 1, and X independently represents or , where * is the attachment site.

4. An application of a luminous auxiliary material, characterized in that: The luminescence auxiliary material according to any one of claims 1 to 2 is applied to an organic electroluminescent device.

5. The use according to claim 4, characterized in that: The organic electroluminescent device comprises an organic layer; the organic layer contains the luminescent auxiliary material.

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