Polycyclic aromatic compound and organic electroluminescent device adopting same

Abstract

The invention provides a polycyclic aromatic compound and an organic electroluminescent device adopting the same, and belongs to the field of organic photoelectric materials, and the polycyclic aromatic compound has a structure as shown in a formula I. After the polycyclic aromatic compound provided by the invention is applied to the organic electroluminescent device, the organic electroluminescent device has a good application prospect. Meanwhile, the luminous efficiency of the device is improved, and the service life is prolonged.

Description

Technical Field

[0001] The invention belongs to the field of organic photoelectric materials, and in particular relates to a polycyclic aromatic compound and an organic electroluminescent device using the compound. Background Art

[0002] Organic light emitting diode (OLED) is an electroluminescent device formed by a multi-layer organic thin film structure. It has gradually entered people's field of vision as a new and promising display technology due to its many advantages such as flexibility, fast response speed, wide viewing angle, small size, high brightness and bright colors. Currently, OLED has been widely used in displays such as smart phones, smart watches, tablets and TVs, as well as solid-state lighting.

[0003] In the field of display and solid-state lighting, the core of OLED display technology is organic light-emitting materials, which achieve full-color gamut light emission based on the mixture of red light materials, green light materials and blue light materials. The development of new light-emitting materials is the driving force for the continuous advancement of electroluminescent technology and is also a research hotspot in the organic electroluminescent industry. At present, many red and green light emitters have been developed and are widely used in commercial OLED products. However, there are few developments of new blue light organic electroluminescent materials with narrow half-width, high color purity, high luminous efficiency and better luminous life. Therefore, the development of a new blue light organic electroluminescent material with high luminous efficiency, long service life, narrow half-width and high color purity has become a research hotspot.

[0004] At present, the mainstream is to construct polycyclic aromatic compounds formed by condensing multiple aromatic rings with boron atoms and heteroatoms such as nitrogen and oxygen, and to use the multiple vibration effect (MR effect) to utilize the opposite vibrations of boron and heteroatoms such as nitrogen and oxygen, that is, to prepare new blue light organic electroluminescent materials containing special rigid material systems of boron atoms, nitrogen and oxygen heteroatoms. This type of fluorescent molecule has high radiation transition rate, narrow half-peak width, and high color purity, but the performance in device life and luminous efficiency is not particularly ideal, and the industrialization process of this technology still faces many key problems. Therefore, the development of new materials has always been a problem that technicians in this field need to solve. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a polycyclic aromatic compound and an organic electroluminescent device using the same. The polycyclic aromatic compound provided by the present invention has the advantage that after being used in an organic electroluminescent device, the luminous efficiency of the device is improved and the service life is increased.

[0006] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0007] In one aspect, the present invention provides a polycyclic aromatic compound having a structure shown in Formula I:

[0008]

[0009] In formula I, Y is selected from R, , ;

[0010] R is hydrogen, deuterium, -F, -Cl, -Br, -I, -SF5, hydroxyl, cyano, nitro, amino, amidino, hydrazine, hydrazone, carboxylic acid or its salt, sulfonic acid or its salt, phosphate or its salt, substituted or unsubstituted C1-C60 alkyl, substituted or unsubstituted C2-C60 alkenyl, substituted or unsubstituted C2-C60 alkynyl, substituted or unsubstituted C1-C60 alkoxy, substituted or unsubstituted C1-C60 alkylthio, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C1-C10 heterocycloalkyl, substituted or unsubstituted C3-C10 cyclo alkenyl, substituted or unsubstituted C1-C10 heterocycloalkenyl, substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C6-C60 aryloxy, substituted or unsubstituted C6-C60 arylthio, substituted or unsubstituted C1-C60 heteroaryl, substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, substituted or unsubstituted monovalent non-aromatic heterocondensed polycyclic group, Si(Q1)(Q2)(Q3), -Ge(Q1)(Q2)(Q3), -B(Q4)(Q5), -P(=O)(Q6)(Q7), or -P(Q6)(Q7);

[0011] The above Q1 to Q7 are each independently hydrogen; deuterium; -F; -Cl; -Br; -I; hydroxyl; cyano; nitro; amidino; hydrazine; hydrazone; carboxylic acid or its salt; sulfonic acid or its salt; phosphate or its salt; C1-C30 alkyl, C2-C30 alkenyl, C2-C30 alkynyl, C1-C30 alkoxy, C3-C10 cycloalkyl, C1-C10 heterocycloalkyl, C3-C10 cycloalkenyl or C1-C10 heterocycloalkenyl substituted or unsubstituted by deuterium, -F, cyano, C1-C30 alkyl, C6-C30 aryl, deuterated C6-C30 aryl, fluorinated C6-C30 aryl or any combination thereof; Alkyl, fluorinated C1-C30 alkyl, C6-C30 aryl, deuterated C6-C30 aryl, fluorinated C6-C30 aryl, or any combination thereof, substituted or unsubstituted C6-C30 aryl, C1-C30 heteroaryl, C6-C30 aryloxy, or C6-C30 arylthio; a monovalent non-aromatic condensed polycyclic group; or a monovalent non-aromatic heterocondensed polycyclic group;

[0012] X1 and X2 are independently selected from , , where X1 and X2 may be the same or different;

[0013] R1-R8 are independently selected from hydrogen, deuterium, -F, -Cl, -Br, -I, -SF5, hydroxyl, cyano, CF3, nitro, amino, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C6-C30 heteroaryl, and the heteroatom thereof contains at least one of O, S, N, Si, Ge or Se;

[0014] X3 and X4 are independently selected from , , , , , , , , where X3 and X4 can be the same or different, and * represents the connection site of the group;

[0015] in, , , or The two R's a At least one of them is selected from F and the other is R a Then it is Rc;

[0016] , , , or Two R's b At least one of them is a substituent other than hydrogen or deuterium, and the other R b Then R c ;

[0017] Where R a , R b and R c Each independently selected from hydrogen, deuterium, fluorine, cyano, CF3, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C6 alkyl, phenyl, biphenyl or naphthyl;

[0018] m is independently selected from 0, 1, 2, 3, 4 or 5;

[0019] All hydrogens in Formula I are independently substituted with deuterium or unsubstituted with deuterium.

[0020] Preferably, the polycyclic aromatic compound has the compound structure shown in I-1 to I-3:

[0021] .

[0022] All hydrogens in Formulae I-1 to I-3 are independently substituted with deuterium or not substituted with deuterium.

[0023] Preferably, R1-R8 are independently selected from hydrogen, deuterium, fluorine, cyano, CF3, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C6 alkyl, phenyl, biphenyl or naphthyl.

[0024] In the present invention, the terms "substituted or unsubstituted C1-C60 alkyl", "substituted or unsubstituted C2-C60 alkenyl", "substituted or unsubstituted C2-C60 alkynyl", "substituted or unsubstituted C1-C60 alkoxy", "substituted or unsubstituted C1-C60 alkylthio", "substituted or unsubstituted C3-C10 cycloalkyl", "substituted or unsubstituted C1-C10 heterocycloalkyl", "substituted or unsubstituted C3-C10 cycloalkenyl", "substituted or unsubstituted C1-C10 heterocycloalkenyl", "substituted or unsubstituted C6-C60 aryl", "substituted or unsubstituted C6-C60 aryloxy", "substituted or unsubstituted C6-C60 aryloxy" and "substituted or unsubstituted C6-C60 aryloxy" are used herein. "substituted or unsubstituted C6-C60 arylthio", "substituted or unsubstituted C6-C60 arylthio", "substituted or unsubstituted C1-C60 heteroaryl", "substituted or unsubstituted C1-C30 alkyl", "substituted or unsubstituted C1-C30 alkyl", "substituted or unsubstituted C2-C30 alkenyl", "substituted or unsubstituted C2-C30 alkynyl", "substituted or unsubstituted C1-C30 alkoxy", "substituted or unsubstituted C1-C30 alkylthio", "substituted or unsubstituted C3-C10 cycloalkyl", "substituted or unsubstituted C1-C10 heterocycloalkyl", "substituted or unsubstituted C3-C10 cycloalkenyl", "substituted or unsubstituted C1-C10 heterocycloalkenyl", " the following may be used herein to represent the present invention; "substituted or unsubstituted C6-C30 aryl", "substituted or unsubstituted C6-C30 aryloxy", "substituted or unsubstituted C6-C30 aryloxy", "substituted or unsubstituted C6-C30 arylthio", "substituted or unsubstituted C6-C30 arylthio", "substituted or unsubstituted C6-C30 arylthio", "substituted or unsubstituted C6-C30 arylthio", "substituted or unsubstituted C1-C30 heteroaryl", "substituted or unsubstituted C1-C30 alkyl", "substituted or unsubstituted C1-C15 alkyl", "substituted or unsubstituted C2-C15 alkenyl", "substituted or unsubstituted C2-C15 alkynyl", "substituted or unsubstituted C1-C15 alkoxy", "substituted or unsubstituted C1-C24 alkylthio", "substituted or unsubstituted C

[0063] The alkyl, alkenyl, alkynyl, alkoxy, alkylthio ...The number of carbon atoms in a cycloalkyl group, a heterocycloalkyl group, a cycloalkenyl group, a heterocycloalkenyl group, an aryl group, an aryloxy group, or an arylthio group refers to the number of carbon atoms constituting an unsubstituted aryl group, an unsubstituted alkyl group, or the total number of carbon atoms constituting a heteroaryl group, without taking into account the number of carbon atoms in the substituent.

[0025] Preferably, the “substituted” means substituted by one or at least two substituents connected to each other selected from the group consisting of hydrogen, deuterium, halogen, cyano, trimethylsilyl (TMS), trimethylgermanyl, trifluoromethyl, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, 1-methylhexyl, phenyl, naphthyl, anthracenyl, phenanthrenyl, thienyl, furanyl, pyrrolyl, benzothienyl, benzofuranyl, pyridyl, indolyl, cyclopentanyl, cyclohexanyl and adamantyl.

[0026] Preferably, the polycyclic aromatic compound is selected from any one of the following compounds:

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038] .

[0039] The organic electroluminescent compound of the present invention can be prepared by a synthetic method known to those skilled in the art. For example, it is preferably prepared by the following reaction scheme.

[0040]

[0041] The definitions of the groups in the above formula are the same as those mentioned above and will not be repeated here.

[0042] Step 1 specifically includes the following steps: under nitrogen protection, raw material A (1.3-1.4eq) and raw material B (1.0eq) are dissolved in a toluene solution, sodium tert-butoxide (2.00eq), tri(dibenzylideneacetone)dipalladium (0.01eq), and tri-tert-butylphosphine (0.05eq) are added, stirred evenly, heated to 90-110°C, and refluxed for 4-6h; after the reaction is completed, the temperature is slightly lowered, diatomaceous earth is used for filtering to remove salt and catalyst, the filtrate is cooled to room temperature, washed with water three times, the organic phase is retained, and then the aqueous phase is extracted with ethyl acetate; after the organic phases are combined, they are dried with anhydrous magnesium sulfate, and the solvent is removed with a rotary evaporator, and dissolved in petroleum ether / ethanol, recrystallized, filtered, and the filter cake is rinsed with petroleum ether for multiple times, and placed in a 60°C oven for drying for 5h to obtain intermediate 1;

[0043] Step 2 specifically includes the following steps: under nitrogen protection, dissolving raw material C (1.3-1.4 eq) and raw material D (1.0 eq) in a toluene solution, adding sodium tert-butoxide (2.00 eq), tri(dibenzylideneacetone)dipalladium (0.01 eq), and tri-tert-butylphosphine (0.05 eq), stirring evenly, heating to 90-110° C., and reflux reaction for 4-6 hours; after the reaction is completed, the temperature is slightly lowered, and diatomaceous earth is used for filtering to remove salt and catalyst, and the filtrate is cooled to room temperature, washed with water three times, and the organic phase is retained, and then the aqueous phase is extracted with ethyl acetate; after the organic phases are combined, they are dried with anhydrous magnesium sulfate, and the solvent is removed with a rotary evaporator, and dissolved in petroleum ether / ethanol, recrystallized, filtered, and the filter cake is rinsed with petroleum ether for multiple times, and placed in a 60° C. oven for drying for 5 hours to obtain intermediate 2;

[0044] Step 3 specifically includes the following steps:

[0045] Under nitrogen protection, raw material E (1.0 eq) and intermediate 1 (1.0 eq) were dissolved in toluene solution, sodium tert-butoxide (2.00 eq), tri(dibenzylideneacetone)dipalladium (0.01 eq), and tri-tert-butylphosphine (0.05 eq) were added, stirred evenly, heated to 90-120°C, and refluxed for 8-12 h. After the reaction was completed, the temperature was slightly lowered, filtered using diatomaceous earth to remove salt and catalyst, and the filtrate was cooled to room temperature and washed three times with water, the organic phase was retained, and then the aqueous phase was extracted with ethyl acetate. After the organic phases were combined, they were dried with anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator; dissolved in petroleum ether / ethanol, recrystallized, filtered, the filter cake was rinsed with petroleum ether several times, and dried in a 60°C oven for 5 h to obtain intermediate 3.

[0046] Step 4 specifically includes the following steps:

[0047] Under nitrogen protection, intermediate 2 (1.0 eq) and intermediate 3 (1.0 eq) were dissolved in toluene solution, sodium tert-butoxide (2.00 eq), tri(dibenzylideneacetone)dipalladium (0.01 eq), tri-tert-butylphosphine (0.05 eq) were added, stirred evenly, heated to 90-120°C, and refluxed for 8-12 h; after the reaction, the temperature was slightly lowered, filtered using diatomaceous earth to remove salt and catalyst, and the filtrate was cooled to room temperature and washed three times with water, the organic phase was retained, and then the aqueous phase was extracted with ethyl acetate; after the organic phases were combined, they were dried with anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator; dissolved in petroleum ether / ethanol, recrystallized, filtered, the filter cake was rinsed with petroleum ether several times, and dried in a 60°C oven for 5 h to obtain intermediate 4.

[0048] Step 5 specifically includes the following steps:

[0049] Under nitrogen protection, the intermediate 4 (1.0 eq) was dissolved in 1,2-dichlorobenzene, and boron triiodide (1.5-1.6 eq) was added thereto, stirred evenly, heated to 130-150°C, and refluxed for 24 hours; after the reaction was completed, the temperature was cooled to room temperature, diisopropylamine (5.0 eq) was added to the reaction mixture, and stirring was continued for 1-2 hours, and then an excess of petroleum ether was added thereto, and stirring was continued for 12-14 hours. Solids precipitated and were filtered. The collected solids were placed in a 60°C oven and dried for 5 hours. The remaining substance was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V=10:4) to obtain the compound of formula I.

[0050] In another aspect, the present invention provides an organic electroluminescent device, comprising an anode and a cathode and an organic thin film layer disposed between the anode and the cathode, wherein the organic thin film layer comprises the polycyclic aromatic compound as described above.

[0051] Preferably, the organic thin film layer comprises a light-emitting layer, the light-emitting layer comprises a host material and a doping material, and the doping material comprises the polycyclic aromatic compound as described above.

[0052] Preferably, the organic thin film 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 or an electron injection layer.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] The polycyclic aromatic compounds of the present invention introduce aromatic amine or carbazole on the basis of the parent nucleus. The excessive phenyl groups in the compounds will increase the packing density and steric hindrance of the compounds, affect the evaporation temperature of the compounds, and thus reduce the luminous efficiency and life. Carbazole has a large conjugated property. On the one hand, it can improve the stacking effect between molecules. On the other hand, it can increase the horizontal arrangement of molecules, so that the molecules are effectively arranged horizontally, thereby effectively increasing the luminous efficiency. When the aromatic amine groups are all substituted with aromatic groups, the energy level is low, which avoids the localization of carrier migration, can reduce the hole transmission energy barrier, thereby improving the migration rate and improving the luminous efficiency. On this basis, the introduction of fluorine can reduce the HOMO and LUMO energy levels of organic matter, enhance the charge carrier mobility, and also strengthen the electrostatic force between molecules, so that the material stability is better and the device life is greatly improved. The device life and efficiency prepared by the doping material in the present invention are significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 This is the H NMR spectrum of compound 114. DETAILED DESCRIPTION

[0056] 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.

[0057] In addition, it should be noted that the numerical values ​​given in the following examples are as accurate as possible, but those skilled in the art understand that due to unavoidable measurement errors and experimental operation problems, each number should be understood as an approximate number rather than an absolutely accurate value.

[0058] Reference to common knowledge is as follows:

[0059] "Transition Metal Organic Chemistry" (Original Sixth Edition), Robert H. Crabtree, Publisher: Shanghai East China University of Science and Technology Press, Publication Date: 2017-09-00, ISBN: 978-7-5628-5111-0, page 388.

[0060] "Organic Chemistry and Optoelectronic Materials Experimental Tutorial", Chen Runfeng, Publisher: Southeast University Press, Publication Date: 2019-11-00, ISBN: 9787564184230, Page 174.

[0061] Example 1

[0062]

[0063] Since there is no prior art for raw material A-114, the following synthetic route is adopted for synthesis:

[0064] .

[0065] Under nitrogen environment, raw material a-114 (1.0eq, CAS number: 98-80-6) and raw material b-114 (1.0eq, CAS number: 67567-26-4) were added to a mixed solution of toluene, ethanol and water in a volume ratio of 2:1:1, potassium carbonate (2.2eq) and tetrakis(triphenylphosphine)palladium (0.01eq) were added thereto, stirred evenly, heated to 85°C, and refluxed for 4 hours. After the reaction was completed, the temperature was slightly lowered, and diatomaceous earth was used for filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, it was washed three times with water, the organic phase was retained, and the aqueous phase was extracted with dichloromethane; the organic phases were combined and concentrated, and a mixed solution of dichloromethane and petroleum ether was used as an eluent, and the raw material A-114 (yield: 63.7%) was obtained by column chromatography purification.

[0066] Step 1 specifically includes the following steps: under nitrogen protection, raw material A-114 (1.4eq) and raw material B-114 (1.0eq, CAS number: 185112-61-2) are dissolved in toluene solution, sodium tert-butoxide (2.00eq), tri(dibenzylideneacetone)dipalladium (0.01eq), tri-tert-butylphosphine (0.05eq) are added, stirred evenly, heated to 110°C, and refluxed for 6h; after the reaction is completed, the temperature is slightly lowered, diatomaceous earth is used for filtering, salt and catalyst are removed, the filtrate is cooled to room temperature, washed three times with water, the organic phase is retained, and then the aqueous phase is extracted with ethyl acetate; after the organic phases are combined, they are dried with anhydrous magnesium sulfate, and the solvent is removed with a rotary evaporator, and dissolved in petroleum ether / ethanol, recrystallized, filtered, and the filter cake is rinsed with petroleum ether for multiple times, and placed in a 60°C oven for drying for 5h to obtain intermediate 1 (yield: 82.3%).

[0067] Step 2 specifically includes the following steps:

[0068] Under nitrogen protection, the raw material C-114 (2.0eq, CAS No.: 750573-26-3) and intermediate 1 (1.0eq) were dissolved in toluene solution, and sodium tert-butoxide (2.00eq), tri(dibenzylideneacetone)dipalladium (0.01eq), and tri-tert-butylphosphine (0.05eq) were added, stirred evenly, heated to 120°C, and refluxed for 12h; after the reaction, the temperature was slightly lowered, filtered with diatomaceous earth to remove salt and catalyst, and the filtrate was cooled to room temperature and washed three times with water, the organic phase was retained, and then the aqueous phase was extracted with ethyl acetate; after the organic phases were combined, they were dried with anhydrous magnesium sulfate, and the solvent was removed with a rotary evaporator; dissolved in petroleum ether / ethanol, recrystallized, filtered, the filter cake was rinsed with petroleum ether several times, and dried in a 60°C oven for 5h to obtain intermediate 2 (yield: 88.4%).

[0069] Step 3 specifically includes the following steps:

[0070] Under nitrogen protection, intermediate 2 (1.0 eq) was dissolved in 1,2-dichlorobenzene, and boron triiodide (1.5 eq) was added thereto, stirred evenly, heated to 150°C, and refluxed for 24 h; after the reaction was completed, the temperature was cooled to room temperature, diisopropylamine (5.0 eq) was added to the reaction mixture, and stirring was continued for 1 h. Then, an excess of petroleum ether was added thereto, and stirring was continued for 12 h. Solids precipitated and were filtered. The collected solids were placed in a 60°C oven and dried for 5 h. The remaining substance was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V=2:10) to obtain compound 114 (yield: 26.1%, MS (ESI, m / Z): [M+H] + =1139.59).

[0071] The obtained compound 114 was tested and analyzed, and the results were as follows:

[0072] The H NMR spectrum of compound 114 is shown in Figure 1 shown.

[0073] HPLC purity: >99.95%.

[0074] Elemental Analysis:

[0075] The test values ​​are: C, 81.85; H, 4.16; B, 1.02; N, 6.26; F, 6.84.

[0076] The synthesis methods of other compounds are the same as those in the above embodiments and are not described in detail here. The present invention also provides an organic electroluminescent device, which is made of the organic light-emitting material, more specifically, made of the organic light-emitting material of the compound of chemical formula I.

[0077] Device Example 1: Manufacturing an organic electroluminescent device containing compound 114, specifically comprising the following steps:

[0078] a. ITO anode: Wash the ITO (indium tin oxide)-Ag-ITO (indium tin oxide) glass substrate with a coating thickness of 150nm in distilled water twice, ultrasonically wash for 30 minutes, and then repeatedly wash it with distilled water twice, ultrasonically wash for 10 minutes. After washing, transfer it to a spin dryer for drying, and finally 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, use an evaporation machine to carry out the evaporation device process, and evaporate other functional layers on it in sequence.

[0079] b. HIL (hole injection layer): 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 and P-dopant was 98:2, and the thickness was 10nm.

[0080] c. HTL (hole transport layer): 130nm of HT-1 was vacuum-deposited on the hole injection layer at a deposition rate of 1Å / s as the hole transport layer.

[0081] d. Light-emitting auxiliary layer: 10 nm EBL-1 was vacuum-deposited on the hole transport layer at a deposition rate of 0.5 Å / s as a light-emitting auxiliary layer.

[0082] e. EML (light-emitting layer): Then, on the above-mentioned light-emitting auxiliary layer, a host material (Host) with a thickness of 20 nm and the compound 114 provided in the above-mentioned Example 1 as a doping material (Dopant) are vacuum evaporated at a deposition rate of 1Å / s as a light-emitting layer, wherein the evaporation rate ratio of Host to Dopant is 97:3.

[0083] f. HBL (hole blocking layer): 5 nm of HB-1 was vacuum-deposited on the light-emitting layer at a deposition rate of 0.5 Å / s as a hole blocking layer.

[0084] g. ETL (electron transport layer): 30 nm of ET-1 was vacuum-deposited on the hole blocking layer at a deposition rate of 1 Å / s as the electron transport layer.

[0085] h. EIL (electron injection layer): 1.0 nm of Yb film was evaporated at a deposition rate of 0.5 Å / s to form an electron injection layer.

[0086] 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.

[0087] j. Light extraction layer: CPL-1 with a thickness of 65nm is vacuum-deposited on the cathode at a deposition rate of 1Å / s as a light extraction layer. The evaporated substrate is then packaged. First, the cleaned cover is coated with UV glue using a glue coating device, and then the coated cover is moved to the pressing section, the evaporated substrate is placed on the upper end of the cover, and finally the substrate and cover are bonded by the bonding equipment, and the UV glue is cured by light.

[0088] The required material structure is as follows:

[0089]

[0090] Device Example 2-Device Example 69 Referring to the above method, the compound 114 used in Device Example 1 was replaced by compounds 2, 7, 10, 15, 23, 25, 29, 31, 32, 33, 43, 50, 51, 56, 60, 62, 64, 70, 71, 77, 83, 89, 97, 105, 109, 111, 112, 115, 117, 120, 127, 130, 134, 136, 140, 147, 156, 159, 164, 169, 174, 180, 185, 191, 195, 200, 204, 207, 211, 213, 215, 217, 220, 223, 226, 232, 237, 241, 247, 252, 258, 264, 267, 274, 280, 283, 285 and 286 are used as doping materials to prepare corresponding organic electroluminescent devices.

[0091] Device Comparative Example 1: This comparative example provides an organic electroluminescent device. The only difference between the preparation method of the organic electroluminescent device and the device embodiment 1 is that the organic electroluminescent device uses existing comparative compounds a, b, c, and d to replace the doping material in the above device embodiment 1 for evaporation to prepare device comparative examples 1 to 4. Among them, the chemical structural formulas of comparative compounds a, b, c, and d are as follows:

[0092] .

[0093] The driving voltage, luminous efficiency, BI value and lifespan of the organic electroluminescent devices obtained from the device embodiments 1 to 69 and the device comparative examples 1 to 4 were characterized at a brightness of 1000 (nits). The test results are shown in Table 1 below.

[0094] Table 1

[0095]

[0096]

[0097]

[0098] According to the above table, by changing the substituents and the positions of the substituents, the performance of the device will be changed, and the luminous efficiency and life of the device will be improved to varying degrees.

[0099] Among them, compound 114, compound 116 and compound a are parallel comparative examples. The difference between them lies in whether the molecular structure contains fluorine. The introduction of fluorine into the molecular structure can reduce the HOMO and LUMO energy levels of the organic matter and enhance the charge carrier mobility. At the same time, it can also strengthen the electrostatic force between molecules, making the material more stable, effectively increasing the luminous efficiency, and greatly improving the device life.

[0100] Compound a and compound c are parallel comparative examples. The difference between them is that a carbazole is missing from the parent core. Aromatic amine or carbazole is introduced on the basis of the parent core. The excessive phenyl groups in the compound will increase the packing density and steric hindrance of the compound, affect the evaporation temperature of the compound, and thus reduce the luminous efficiency and life. Carbazole has a large conjugated property. On the one hand, it can improve the stacking effect between molecules. On the other hand, it can increase the horizontal arrangement of molecules, so that the molecules are effectively arranged horizontally, thereby effectively increasing the luminous efficiency and device life.

[0101] Compared with the organic electroluminescent device prepared by using the comparative compounds a to d as doping materials in the light-emitting layer, the organic electroluminescent device prepared by using the compound provided by the present invention as the doping material in the light-emitting layer has improved driving voltage, improved luminous efficiency, and increased device life by 52-165h.

[0102] The applicant declares that the present invention uses the above-mentioned embodiments to illustrate the polycyclic aromatic compounds of the present invention and the organic light-emitting devices using the same, but the present invention is not limited to the above-mentioned process steps, that is, it does not mean that the present invention must rely on the above-mentioned process steps 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 scope of protection and disclosure of the present invention.

Claims

1. A polycyclic aromatic compound, characterized in that: The polycyclic aromatic compound has a structure shown in Formula I: ； In formula I, Y is selected from R, , ; R is hydrogen, deuterium, -F, -Cl, -Br, -I, -SF5, hydroxyl, cyano, nitro, amino, amidino, hydrazine, hydrazone, carboxylic acid or its salt, sulfonic acid or its salt, phosphate or its salt, substituted or unsubstituted C1-C60 alkyl, substituted or unsubstituted C2-C60 alkenyl, substituted or unsubstituted C2-C60 alkynyl, substituted or unsubstituted C1-C60 alkoxy, substituted or unsubstituted C1-C60 alkylthio, substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted C1-C10 heterocycloalkyl, substituted or unsubstituted C3-C10 cyclo alkenyl, substituted or unsubstituted C1-C10 heterocycloalkenyl, substituted or unsubstituted C6-C60 aryl, substituted or unsubstituted C6-C60 aryloxy, substituted or unsubstituted C6-C60 arylthio, substituted or unsubstituted C1-C60 heteroaryl, substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, substituted or unsubstituted monovalent non-aromatic heterocondensed polycyclic group, Si(Q1)(Q2)(Q3), -Ge(Q1)(Q2)(Q3), -B(Q4)(Q5), -P(=O)(Q6)(Q7), or -P(Q6)(Q7); The above Q1 to Q7 are each independently hydrogen; deuterium; -F; -Cl; -Br; -I; hydroxyl; cyano; nitro; amidino; hydrazine; hydrazone; carboxylic acid or its salt; sulfonic acid or its salt; phosphate or its salt; C1-C30 alkyl, C2-C30 alkenyl, C2-C30 alkynyl, C1-C30 alkoxy, C3-C10 cycloalkyl, C1-C10 heterocycloalkyl, C3-C10 cycloalkenyl or C1-C10 heterocycloalkenyl substituted or unsubstituted by deuterium, -F, cyano, C1-C30 alkyl, C6-C30 aryl, deuterated C6-C30 aryl, fluorinated C6-C30 aryl or any combination thereof; Alkyl, fluorinated C1-C30 alkyl, C6-C30 aryl, deuterated C6-C30 aryl, fluorinated C6-C30 aryl, or any combination thereof substituted or unsubstituted C6-C30 aryl, C1-C30 heteroaryl, C6-C30 aryloxy, C6-C30 arylthio; monovalent non-aromatic condensed polycyclic group; or monovalent non-aromatic heterocondensed polycyclic group; X1 and X2 are independently selected from , , where X1 and X2 are the same or different; R1-R8 are independently selected from hydrogen, deuterium, -F, -Cl, -Br, -I, -SF5, hydroxyl, cyano, CF3, nitro, amino, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C6-C30 heteroaryl, and the heteroatom thereof contains at least one of O, S, N, Si, Ge or Se; X3 and X4 are independently selected from , , , , , , , , wherein X3 and X4 are the same or different, and * represents the attachment site of the group; in, , , or The two R's a At least one of them is selected from F and the other is R a Then it is Rc; , , , or Two R's b At least one of them is a substituent other than hydrogen or deuterium, and the other R b Then R c ; Where R a , R b and R c Each independently selected from hydrogen, deuterium, fluorine, cyano, CF3, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C6 alkyl, phenyl, biphenyl or naphthyl; m is independently selected from 0, 1, 2, 3, 4 or 5; All hydrogens in Formula I are independently substituted with deuterium or unsubstituted with deuterium.

2. The polycyclic aromatic compound according to claim 1, characterized in that The polycyclic aromatic compounds have the compound structures shown in I-1 to I-3: ； All hydrogens in Formulae I-1 to I-3 are independently substituted with deuterium or not substituted with deuterium.

3. The polycyclic aromatic compound according to claim 2, characterized in that: R1-R8 are independently selected from hydrogen, deuterium, fluorine, cyano, CF3, trimethylsilyl, trimethylgermanyl, substituted or unsubstituted C1-C6 alkyl, phenyl, biphenyl or naphthyl.

4. The polycyclic aromatic compound according to claim 1 or 3, characterized in that: The “substituted” means substituted by one or at least two substituents connected to each other selected from the group consisting of hydrogen, deuterium, halogen, cyano, trimethylsilyl, trimethylgermanyl, trifluoromethyl, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, 1-methylhexyl, phenyl, naphthyl, anthracenyl, phenanthrenyl, thienyl, furanyl, pyrrolyl, benzothienyl, benzofuranyl, pyridyl, indolyl, cyclopentanyl, cyclohexyl and adamantyl.

5. The polycyclic aromatic compound according to claim 1 or 2, characterized in that: The polycyclic aromatic compound is selected from any one of the following compounds: 。 6. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises an anode and a cathode and an organic thin film layer disposed between the anode and the cathode, wherein the organic thin film layer comprises the polycyclic aromatic compound according to any one of claims 1 to 5.

7. The organic electroluminescent device according to claim 6, characterized in that: The organic thin film layer comprises a light-emitting layer, the light-emitting layer comprises a host material and a doping material, and the doping material comprises the polycyclic aromatic compound according to any one of claims 1 to 5.

8. The organic electroluminescent device according to claim 6, characterized in that: The organic thin film 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 or an electron injection layer.

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