Deuterated fused ring compound and application thereof

Abstract

The invention relates to a deuterated fused ring compound and application thereof, and relates to the technical field of photoelectric materials. The deuterated fused ring compound has a structure as shown in a formula 1: # imgabs0 #. The compound provided by the invention has a relatively low energy difference delta EST, and is beneficial to delaying the occurrence of a fluorescence process, so that the internal quantum efficiency is improved; meanwhile, the compound has narrower half-peak width of a light-emitting spectrum band and higher color purity; the organic electroluminescent device prepared from the compound provided by the invention shows lower driving voltage, higher current efficiency and longer service life.

Description

Technical Field

[0001] The present invention relates to the technical field of optoelectronic materials, and in particular to a deuterated fused ring compound and application thereof. Background Art

[0002] Organic light-emitting diode (OLED) is a technology that uses organic materials to emit light under the action of electric current or electric field. In the development of OLED technology, organic light-emitting materials have played a key role. According to the luminescence mechanism, organic light-emitting materials are mainly divided into three categories: traditional fluorescent materials, phosphorescent materials and thermally activated delayed fluorescence (TADF) materials. Traditional fluorescent materials and phosphorescent materials have been used in industrial production, but they have some obvious shortcomings. Due to the limitation of spin quantum statistics, only 25% of singlet excitons of traditional fluorescent materials can emit light through radiation transition, resulting in a maximum internal quantum efficiency of only 25%. After comprehensively considering the light coupling output efficiency, the maximum external quantum efficiency of OLED devices is only 5%. Although fluorescent materials have high reliability and stability, their low external quantum efficiency limits their application. Phosphorescent materials usually contain rare precious metals, which leads to high costs, and the problems of device stability and efficiency decline are more serious, which limits their large-scale commercialization and popularization.

[0003] In recent years, thermally activated delayed fluorescent materials have gradually become a new research hotspot. This material can achieve 100% internal quantum efficiency without the use of precious metals, which not only avoids the use of expensive heavy metals and reduces costs, but is also expected to significantly improve device life and spectral stability. It also has the advantages of high luminous efficiency and environmental friendliness, and is called the third generation of electroluminescent materials. However, current research on thermally activated delayed fluorescent materials is still relatively limited, and the types of materials are single, which cannot meet the needs of OLED device development. New high-performance thermally activated delayed fluorescent materials are in urgent need of development. In view of this, the present invention provides a deuterated fused ring compound and its application. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a deuterated condensed ring compound and application thereof.

[0005] The technical solution of the present invention to solve the above technical problems is as follows:

[0006] In a first aspect, a deuterated fused ring compound is provided, wherein the deuterated fused ring compound has a structure as shown in Formula 1:

[0007]

[0008] In Formula 1, R1-R2 are the same or different and are independently selected from any one of the following structures: hydrogen, deuterium, cyano, halogen, an alkyl group having 1 to 10 carbon atoms which is unsubstituted or substituted by deuterium or halogen, an aryl group having 6 to 25 carbon atoms which is unsubstituted or substituted by at least one substituent selected from cyano, deuterium, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, or a deuterated alkyl group having 1 to 10 carbon atoms, and a heterocyclic aryl group having 3 to 20 carbon atoms which is unsubstituted or substituted by at least one substituent selected from cyano, deuterium, an alkyl group having 1 to 10 carbon atoms, or a deuterated alkyl group having 1 to 10 carbon atoms;

[0009] In formula 1, n1-n2 are the same or different and are independently selected from 1 or 2;

[0010] In formula 1 Represents empty or single key; when When it is empty, X1-X2 are the same or different and independently selected from any one of the following structures: O, S; When it represents a single bond, X1-X2 are the same or different and are independently selected from any one of the following structures: N(A3 or A4);

[0011] In Formula 1, A3-A4 are the same or different and are independently selected from any one of the following structures: an aryl group having 6 to 25 carbon atoms which is unsubstituted or substituted with at least one substituent selected from cyano, deuterium, and an alkyl group having 1 to 10 carbon atoms; a heterocyclic aromatic group having 3 to 20 carbon atoms which is unsubstituted or substituted with at least one substituent selected from cyano, deuterium, an alkyl group having 1 to 10 carbon atoms, and an aryl group having 6 to 30 carbon atoms; or A3 and A1, A4 and A2 are the same or different and are connected by any one of a single bond, O, S, and C(R3)(R4) to form a large conjugated aromatic heterocyclic structure;

[0012] In Formula 1, R3-R4 are the same or different and are selected from any one of the following structures: an alkyl group having 1 to 5 carbon atoms;

[0013] In Formula 1, L1 is selected from any one of the following structures: a single bond, an unsubstituted or substituted aryl group having 6 to 25 carbon atoms selected from cyano, deuterium, an alkyl group having 1 to 10 carbon atoms, a deuterated alkyl group having 1 to 10 carbon atoms, and at least one substituent selected from Formula 1;

[0014] In Formula 1, Ar1 is selected from any one of the following structures: a carbazolyl group substituted with at least one substituent selected from deuterium and an alkyl group having 1 to 10 carbon atoms; and the deuterium substitution ratio in Ar1 is above 80%.

[0015] Furthermore, in Formula 1, the structures of R1, R2, A3, and A4 are the same or different and are independently selected from any one of Formula 2 and Formula 3:

[0016]

[0017] m is selected from: 1, 2, or 3; H in Formula 2 and Formula 3 can be replaced by D.

[0018] In formula 2, R 5a Any one selected from the following structures: hydrogen, deuterium, cyano, halogen, alkyl having 1 to 10 carbon atoms, halogenated alkyl having 1 to 10 carbon atoms, deuterated alkyl having 1 to 10 carbon atoms, phenyl, naphthyl, R 5a Forming a fused ring structure through single bonds or through shared chemical bonds of phenyl groups;

[0019] Or the C atom in Formula 2 is replaced by a N atom to form the structure shown in Formula 2-1;

[0020]

[0021] Preferably, when R 5a Any one selected from the following structures: cyano, halogen, alkyl having 1 to 10 carbon atoms, halogenated alkyl having 1 to 10 carbon atoms, deuterated alkyl having 1 to 10 carbon atoms, m is selected from: 1, 2, 3;

[0022] Preferably, when R 5a Any one selected from the following structures: phenyl, naphthyl, m is selected from: 1;

[0023] Preferably, Formula 2 is selected from: phenyl, phenyl containing 1, 2, 3, 4, 5 deuterium atoms, unsubstituted or substituted cyano, methyl, tert-butyl, ethyl, propyl, isopropyl, deuterated methyl, deuterated tert-butyl, deuterated ethyl, deuterated propyl, deuterated isopropyl, phenyl substituted with fluorine, naphthyl, biphenyl;

[0024] In formula 3, R 5b Any one selected from the following structures: hydrogen, deuterium, cyano, an alkyl group having 1 to 10 carbon atoms, phenyl, or phenyl substituted by deuterium, cyano, or an alkyl group having 1 to 10 carbon atoms;

[0025] In formula 3, X3 is selected from any one of the following structures: O, S, N(R 5c );

[0026] In formula 3, R 5c Any one selected from the following structures: phenyl, biphenyl which is unsubstituted or substituted with at least one substituent selected from cyano, deuterium and an alkyl group having 1 to 10 carbon atoms.

[0027] Further, the structure of Formula 1 is selected from any one of Formula 4 to Formula 7:

[0028]

[0029] X 4a , X 4b The same or different are independently selected from any one of the following structures: single bond, O, S, C(CH3)(CH3).

[0030] Further, L1 in Formula 1, Formula 4-Formula 7 is selected from any one of the following structures: a single bond, a phenyl group, a biphenyl group, a naphthyl group which is unsubstituted or substituted by at least one substituent selected from a cyano group and an alkyl group having 1 to 5 carbon atoms;

[0031] Preferably L1 is selected from the group consisting of phenyl, naphthyl, pyridyl, phenyl and naphthyl substituted with at least one cyano group and an alkyl group having 1 to 5 carbon atoms.

[0032] Furthermore, A in Formula 1, Formula 4-Formula 7 r1 The structure is selected from any one of the following structures: a carbazolyl group substituted by a deuterated alkyl group having 1 to 5 carbon atoms; and the number of alkyl substitutions is 1 or 2, A r1 The deuterium substitution rate is 100%.

[0033] Further, the structure of Ar1 is selected from any one of the following:

[0034]

[0035] Further, the alkyl group having 1 to 10 carbon atoms is selected from: an alkyl group having 1 to 8 carbon atoms, an alkyl group having 1 to 7 carbon atoms, an alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 5 carbon atoms;

[0036] More preferably, the alkyl group having 1 to 10 carbon atoms is selected from the group consisting of alkyl groups having 1 to 5 carbon atoms.

[0037] Preferably, the alkyl group having 1 to 5 carbon atoms is selected from: methyl, ethyl, tert-butyl, n-propyl, isopropyl;

[0038] The six-membered monocyclic aryl group and the six-membered monoaromatic ring are selected from: phenyl;

[0039] Among them, at least one is selected from: 1, 2, 3 or 1, 2, 3.

[0040] Furthermore, the structure of the deuterated fused ring compound is selected from any one of the following:

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049] In a second aspect, an organic electroluminescent device comprises an anode, a cathode and an organic functional layer located between the anode and the cathode, wherein the organic functional layer comprises at least one of the deuterated fused ring compounds.

[0050] Furthermore, the organic functional layer includes a light-emitting layer, and the light-emitting layer includes at least one of the deuterated fused-ring compounds.

[0051] Furthermore, at least one of the deuterated fused-ring compounds is used as a doping material, a co-dopant material or a host material in the light-emitting layer.

[0052] The beneficial effect of the present invention is that the compound provided by the present invention has a lower energy difference ΔE ST , which is conducive to the occurrence of delayed fluorescence process, thereby improving internal quantum efficiency; at the same time, it has a narrower half-peak width of the luminescence spectrum band and higher color purity; the organic electroluminescent device prepared by the compound provided by the present invention shows a lower driving voltage, higher current efficiency and longer service life (LT95). BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 The structure of the organic electroluminescent device of the present invention;

[0054] 1. Anode; 2. Hole injection layer; 3. Hole transport layer; 4. Electron blocking layer; 5. Light-emitting layer;

[0055] 6. Electron transport layer; 7. Electron injection layer; 8. Cathode. DETAILED DESCRIPTION

[0056] The following will be clearly and completely described in conjunction with the examples, and the described examples are only a part of the examples of the present invention, rather than all the examples. The following description of at least one exemplary embodiment is actually only illustrative and is not intended to be any limitation to the present invention and its application or use. Based on the examples in the present invention, all the other examples obtained by those of ordinary skill in the art without making creative work premises belong to the scope of protection of the present invention. The reagents or instruments used in the present invention are not indicated by the manufacturer, and are all conventional products that can be obtained by commercial purchase. For the processing parameters not particularly indicated, conventional techniques can be used for reference.

[0057] Embodiment 1:

[0058]

[0059] Add 200 ml of dry dioxane to a three-necked flask, flush with nitrogen for 5 minutes to replace the air in the system, add B1-1 (20 g), B1-2 (17.79 g), sodium tert-butoxide (8.45 g), PD2(DBA)3 (0.5 g), tri-tert-butyl phosphine (17.79 g), react at 100 ° C for 12 hours under a nitrogen environment, and monitor the reaction by TLC. After the reaction is completed, add 0.1 mol / L HCl to adjust the pH of the system to 6-7, add water to split, retain the organic phase, spin dry the organic phase, add ethanol and reflux for 1 hour, cool to room temperature, filter, and dry to obtain B1-3 (26.97 g).

[0060] Under nitrogen atmosphere, add 1.6 mol / L hexane solution (46.4 ml) of n-butyl lithium to a flask containing B1-3 (26.97 g) and xylene (300 ml). After the addition is complete, raise the temperature to 70°C and stir for 4 hours, then heat to 100 degrees Celsius, distill off the hexane, cool to -50°C, add boron tribromide (17.97 g), then stir at room temperature for 1 hour, cool to 0°C again, add N,N-diisopropylethylamine (100 ml), heat to 120°C, and stir for 8 hours. After cooling to room temperature, add sodium acetate aqueous solution and toluene for separation, distill off the solvent under reduced pressure, spin dry the solid, add 50 ml ethanol to reflux for 1 hour, cool to room temperature, filter out the solid, spin dry to obtain 20.24 g of the compound shown in Example 1.

[0061] MS: 572.1847.

[0062] Embodiment 2:

[0063] According to the synthesis steps of Example 1, Example 2 was synthesized, and B1-2 in Example 1 was replaced with 3,6-bis(methyl-d3)-9H-carbazole-1,2,4,5,7,8-d6. The remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1.

[0064] MS: 476.5285.

[0065] Embodiment 3:

[0066] According to the synthesis steps of Example 1, Example 3 was synthesized, and B1-1 in Example 1 was replaced with 4,4'-((5-bromo-1,3-phenyl)bis(oxy))bis(tert-butylbenzene), and the remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, and the synthesis was completed.

[0067] MS: 684.5814.

[0068] Embodiment 4:

[0069] According to the synthesis steps of Example 1, Example 4 was synthesized, and B1-1 in Example 1 was replaced with 1,1'-((5-bromo-1,3-phenyl-4,6-d2)bis(oxy))bis(benzene-2,3,4,5-d4), and the remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, and the synthesis was completed.

[0070] MS: 582.7292.

[0071] Embodiment 5:

[0072] According to the synthesis steps of Example 1, Example 5 was synthesized, where B1-1 in Example 1 was replaced with (5-bromo-1,3-phenyl)bis(phenylsulfonane), and the remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, to synthesize

[0073] MS: 604.9217.

[0074] Embodiment 6:

[0075] According to the synthesis steps of Example 1, Example 6 was synthesized, and B1-1 in Example 1 was replaced with (5-bromo-1,3-phenyl)bis([1,1':3',1"-terphenyl]-4-ylsulfane), and the remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, and the synthesis was completed.

[0076] MS:908.6001.

[0077] Embodiment 7:

[0078] According to the synthesis steps of Example 1, Example 7 was synthesized, where B1-1 in Example 1 was replaced with 4', 4"-((5-bromo-1, 3-phenyl)bis(oxy))bis(([1, 1'-biphenyl]-4-carbonitrile)), B1-2 was replaced with 3, 6-bis(methyl-d3)-9H-carbazole-1, 2, 4, 5, 7, 8-d6, and the remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, to synthesize

[0079] MS: 678.1263.

[0080] Embodiment 8:

[0081] According to the synthesis steps of Example 1, Example 8 was synthesized, wherein B1-1 in Example 1 was replaced with (4'-bromo-[1,1'-biphenyl]-3,5-diyl)bis((4-(2-(methyl-d3)prop-2-yl-1,1,1,3,3-d6)phenyl)sulfane), B1-2 was replaced with 1,8-bis(methyl-d3)-9H-carbazole-2,3,4,5,6,7-d6, and the remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, to synthesize

[0082] MS: 714.5681.

[0083] Embodiment 9:

[0084] According to the synthesis steps of Example 1, Example 9 was synthesized, and B1-1 in Example 1 was replaced with 5-fluoro-N1, N1, N3, N3-tetraphenylbenzene-1,3-diamine. The remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1.

[0085] MS:722.6814.

[0086] Embodiment 10:

[0087] According to the synthesis steps of Example 1, Example 10 was synthesized, and B1-1 in Example 1 was replaced with 5-fluoro-N1, N1, N3, N3-tetra(4-tert-butyl)benzene)benzene-1,3-diamine, and the remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, and the synthesis was completed.

[0088] MS:946.2858.

[0089] Embodiment 11:

[0090] According to the synthesis steps of Example 1, Example 11 was synthesized, and B1-1 in Example 1 was replaced with 5-fluoro-N1, N1, N3, N3-tetrakis(4-(2-(methyl-d3)prop-2-yl-1,1,1,3,3-d6)phenyl)benzene-1,3-diamine. The remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, and the synthesis was completed.

[0091]

[0092] MS:982.6397.

[0093] Embodiment 12:

[0094] According to the synthesis steps of Example 1, Example 12 was synthesized, and B1-1 in Example 1 was replaced with 9,9'-(5-fluoro-1,3-phenyl)bis(3,6-diphenyl-9H-carbazole). The remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, and the synthesis was completed.

[0095] MS: 1022.6943.

[0096] Embodiment 13:

[0097] According to the synthesis steps of Example 1, Example 13 was synthesized, where B1-1 in Example 1 was replaced with 10,10'-(5-fluoro-1,3-phenyl)bis(9,9-dimethyl-9,10-dihydroacridine), and the remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, to synthesize

[0098] MS: 802.8941.

[0099] Embodiment 14:

[0100] According to the synthesis steps of Example 1, Example 14 was synthesized, where B1-1 in Example 1 was replaced with 10,10'-(5-fluoro-1,3-phenyl)bis(9,9-dimethyl-9,10-dihydroacridine), B1-2 was replaced with 3,6-bis(methyl-d3)-9H-carbazole-1,2,4,5,7,8-d6, and the remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, to synthesize

[0101] MS: 654.0086.

[0102] Embodiment 15:

[0103] According to the synthesis steps of Example 1, Example 13 was synthesized, and B1-1 in Example 1 was replaced with 3-fluoro-5-(9H-carbazole-9-yl)-N,N-diphenylamine. The remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1.

[0104] MS:720.9580.

[0105] Embodiment 16:

[0106] According to the synthesis steps of Example 1, Example 16 was synthesized, where B1-1 in Example 1 was replaced with 3-fluoro-5-(10H-phenoxazine-10-yl)-N,N-diphenylamine, B1-2 was replaced with 3,6-bis(methyl-d3)-9H-carbazole-1,2,4,5,7,8-d6, and the remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, to synthesize

[0107] MS: 640.2857.

[0108] Embodiment 17:

[0109] According to the synthesis steps of Example 1, Example 17 was synthesized, except that B1-1 in Example 1 was replaced with 3-fluoro-5-phenoxy-N,N-diphenylamine, and the remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, to synthesize

[0110] MS: 647.2371.

[0111] Embodiment 18:

[0112] According to the synthesis steps of Example 1, Example 17 was synthesized, where B1-1 in Example 1 was replaced with 10,10'-(5-fluoro-1,3-phenyl)bis(9,9-dimethyl-9,10-dihydroacridine), B1-2 was replaced with 3-(2-(methyl-d3)prop-2-yl-1,1,1,3,3-d6)-9H-carbazole-1,2,4,5,6,7,8-d7, and the remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1, to synthesize

[0113] MS:738.0012.

[0114] Embodiment 19:

[0115]

[0116] Add 200 ml of dry dioxane to a three-necked flask, flush with nitrogen for 5 minutes to replace the air in the system, add B2-1 (20 g), p-bromoiodobenzene (19.02 g), sodium tert-butoxide (9.69 g), PD2(DBA)3 (0.3 g), and tri-tert-butyl phosphine (10 g), and react at 100°C for 12 hours under a nitrogen environment. Monitor the reaction by TLC. After the reaction, add 0.1 mol / L HCl to adjust the pH of the system to 6-7, add water to split, retain the organic phase, spin dry the organic phase, add ethanol and reflux for 1 hour, cool to room temperature, filter, dry and pass the sample through a silica gel purification column to obtain 9-(4-bromophenyl)-3,6-bis(2-(methyl-d3)propan-2-yl-1,1,1,3,3,3-d6)-9H-carbazole (24.06 g).

[0117] 9-(4-Bromophenyl)-3,6-bis(2-(methyl-d3)propan-2-yl-1,1,1,3,3,3-d6)-9H-carbazole (24.06 g) was dissolved in 200 mL of anhydrous THF, 3.75 g of n-butyl lithium was injected at -78°C, and after reacting for 1 hour, 8.29 g of anhydrous trimethyl borate was injected, and the reaction was continued for 12 hours. Water was added to quench the reaction, and the reaction was extracted with dichloromethane, dried, and recrystallized from n-hexane to obtain 17.81 g of intermediate B-2.

[0118] Add 200 ml of a mixed solution of toluene (2V) / ethanol (1V) / water (1V) into a three-necked flask, flush with nitrogen for 5 minutes to replace the air in the system, add B2-2 (17.81 g), B2-3 (22.52 g), sodium tert-butoxide (6.06 g) and tetrakistriphenylphosphine palladium (0.5 g), react at 85°C for 12 hours under a nitrogen environment, monitor the reaction by TLC, and after the reaction is completed, add 0.1 mol / L HCl to adjust the pH of the system to 6-7, add water to split, retain the organic phase, spin-dry the organic phase, dry the sample and pass it through a silica gel purification column to obtain B2-4 (30.84 g).

[0119] B2-4 (30.84 g) and boron tribromide (8.62 g) were dissolved in 300 mL of anhydrous THF, and 2.60 g of n-butyl lithium was injected at -78 ° C. After reacting for 1 hour, the mixture was heated to room temperature and stirred for 1 hour, cooled to 0 ° C again, and N, N-diisopropylethylamine (100 ml) was added, heated to 120 ° C, and stirred for 8 hours. After cooling to room temperature, sodium acetate aqueous solution and toluene were added for separation, and the solvent was distilled off under reduced pressure. After being spin-dried, the solid was added to 50 ml of ethanol and refluxed for 1 hour, cooled to room temperature, and the solid was filtered out and spin-dried to obtain 27.30 g of the compound shown in Example 19.

[0120] MS:843.0185.

[0121] Embodiment 20:

[0122] According to the synthesis steps of Example 19, Example 20 was synthesized, and B2-1 in Example 1 was replaced with 3-(2-(methyl-d3)propan-2-yl-1,1,1,3,3-d6)-9H-carbazole-1,2,4,5,6,7,8-d7. The remaining reactants, catalysts, solvents, reaction conditions, etc. were the same as those in Example 1.

[0123] MS:778.0684.

[0124] Comparative Examples 1-4

[0125] Comparative Examples 1-4 were synthesized by referring to the methods of Examples 1-20, as shown in Table 1.

[0126] Table 1

[0127]

[0128] Test example

[0129] 1. Performance test of compound monomers:

[0130] (1) Compound monomer ΔE ST , delayed fluorescence lifetime, half peak width test method

[0131] ①ΔE ST : By mixing the compound at 10 -4 The sample was dissolved in toluene solution with a concentration of mol / L to prepare the tested sample. The difference between the onset value of the fluorescence spectrum and the phosphorescence spectrum was measured. The testing instrument was a highly sensitive integrated fluorescence spectrometer.

[0132] ② The half-peak width is the peak width at half the peak height of the fluorescence spectrum at room temperature, that is, the distance between the two points where a straight line parallel to the bottom of the peak passes through the midpoint of the peak height and intersects the two sides of the peak. The fluorescence spectrum is obtained by measuring the compound at 10 -5 The concentration of mol / L was dissolved in toluene solution to prepare the test sample, which was tested using a high-sensitivity integrated fluorescence spectrometer.

[0133] ③ The delayed fluorescence lifetime is obtained by doping the compound at a concentration of 1wt% in polystyrene to prepare the tested sample and testing it using a time-resolved fluorescence spectrometer;

[0134] The test results are shown in Table 2.

[0135] Table 2

[0136] Serial number Compound Name <![CDATA[ΔE ST (eV)]]> Delayed fluorescence lifetime (μs) Half peak width (nm) 1 Example 1 0.16 112 37 2 Example 2 0.13 115 36 3 Example 3 0.11 105 26 4 Example 4 0.10 103 27 5 Example 5 0.12 106 38 6 Example 6 0.13 121 37 7 Example 7 0.12 107 29 8 Example 8 0.10 104 32 9 Example 9 0.11 108 28 10 Example 10 0.10 116 27 11 Embodiment 11 0.11 104 29 12 Example 12 0.14 108 34 13 Embodiment 13 0.13 112 36 14 Embodiment 14 0.15 117 39 15 Embodiment 15 0.17 112 38 16 Example 16 0.13 114 31 17 Embodiment 17 0.14 125 36 18 Embodiment 18 0.13 103 32 19 Embodiment 19 0.11 106 28 20 Embodiment 20 0.16 122 39 21 Comparative Example 1 0.41 51 66 22 Comparative Example 2 0.32 62 57 23 Comparative Example 3 0.39 58 61 24 Comparative Example 4 0.31 70 48

[0137] 2. Performance test of devices using the compounds involved in the present invention (including comparative examples)

[0138] 2.1 Device preparation

[0139] (1) Preparation of Device 1

[0140] The preparation of device 1 comprises the following steps:

[0141] ① The glass substrate with a 50nm ITO transparent film was ultrasonically cleaned with acetone, isopropanol and deionized water for 10 minutes each, vacuum dried at 105°C for 2 hours, and then UV ozone washed for 15 minutes, and then the ITO glass substrate was transferred to a vacuum evaporator.

[0142] ② On the surface where the ITO thin film anode 1 is formed, molybdenum trioxide (MoO3) is vacuum-deposited to form a 10 nm thick hole injection layer 2;

[0143] ③ On the hole injection layer 2, vacuum evaporation of N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine (NPB) was performed to form a hole transport layer 3 with a thickness of 60 nm;

[0144] ④ On the hole transport layer 3, 4,4',4"-tri(carbazole-9-yl)triphenylamine (TCTA) was vacuum-deposited to form a 10 nm electron blocking layer 4.

[0145] ⑤ On the electron blocking layer 4, 9,10-di(2-naphthyl)anthracene (ADN) (as a light-emitting host material, 95 wt%) and the compound prepared in the above-mentioned Synthesis Example 1 as a light-emitting guest material, 5 wt%) were co-vacuum-deposited to form a light-emitting layer 5 with a thickness of 30 nm;

[0146] ⑥ On the light-emitting layer 5, 1,3,5-tri(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi) is vacuum-deposited to form an electron transport layer 6 with a thickness of 30 nm;

[0147] ⑦ On the electron transport layer 6, lithium fluoride (LiF) is vacuum evaporated to form an electron injection layer 7 with a thickness of 1 nm;

[0148] ⑧Finally, magnesium-silver alloy (Mg / Ag) is vacuum-deposited on the electron injection layer 7 to form a cathode 8 with a thickness of 100 nm to obtain the device 1.

[0149] (2) Preparation of Devices 2 to 20

[0150] An organic electroluminescent device was prepared in the same manner as device 1, except that the compounds synthesized in the above Synthesis Example 2 to Synthesis Example 20 were used to replace the compound prepared in the above Synthesis Example 1, respectively, to obtain devices 2 to 20.

[0151] (3) Comparative Device 1 to Comparative Device 3

[0152] Except that the compounds prepared in Synthesis Example 1 were replaced by the above-mentioned compounds of Comparative Examples 1 to 3, organic electroluminescent devices were prepared in the same manner as device 1 to obtain Comparative Devices 1 to 3.

[0153] 2.2 Driving voltage, color coordinates, current efficiency, LT95 test

[0154] The detection methods of driving voltage, color coordinates, current efficiency and LT95 test refer to the records of patents: CN115433180B and CN118561827B; the results are shown in Table 3.

[0155] Table 3

[0156]

[0157] From the data in Tables 2 and 3, it can be seen that there are significant differences in material properties and device performance between Examples 1-20 and Comparative Examples 1-4. First, in terms of the properties of the compound monomers, the compounds in the examples show a lower ΔE ST (energy difference), with a smaller energy gap between the singlet and triplet states, which is conducive to the occurrence of delayed fluorescence process, thereby improving the internal quantum efficiency. In addition, the delayed fluorescence lifetimes of the compounds in Examples 1-20 are generally longer, indicating that these materials can effectively perform reverse intersystem crossing (RISC), that is, return from the triplet excited state to the singlet excited state, which is an important feature of thermally activated delayed fluorescence (TADF) materials. The half-peak width data also show that the compounds in the examples have narrower emission bands and better color purity. In contrast, the compounds in Comparative Examples 1-4 not only have ΔE ST The delayed fluorescence lifetime is shorter and the half-peak width is larger, which indicates that these materials are inferior to the compounds in the examples in terms of TADF performance.

[0158] Secondly, in terms of the performance of organic electroluminescent devices, devices using the compounds synthesized in Examples 1-20 as luminescent guest materials exhibit lower driving voltages, higher current efficiencies, and longer service lives (LT95). Low driving voltages can reduce the energy consumption of devices during operation and extend their service lives; high current efficiencies mean that at the same current density, devices can produce more light output, which is essential for improving the brightness and energy efficiency of displays and lighting equipment. In addition, the color coordinate data show that the luminous color of the embodiment devices is closer to the ideal blue, which is very important for achieving high color quality display technology. The devices prepared using the compounds in Comparative Examples 1-4 have significantly higher driving voltages, lower current efficiencies, and lower service lives, and color coordinates that deviate from dark blue, which further demonstrates the superiority of the compounds in the embodiments.

[0159] In summary, by comparing the data of Examples 1-20 with Comparative Examples 1-4, it can be concluded that the new TADF material of the present invention performs well in terms of material properties and device performance, especially in terms of reducing driving voltage, improving current efficiency, extending device life and optimizing luminescent color. These advantages make the material of the present invention very suitable as a light-emitting layer 5 material for efficient organic electroluminescent devices, and are expected to promote the development of next-generation display and lighting technologies. ST and a short delayed fluorescence lifetime, resulting in its poor performance in practical applications, confirming the effectiveness of the material design and synthesis strategy of the present invention.

[0160] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A deuterated fused ring compound, characterized in that: The deuterated fused ring compound has a structure shown in Formula 1: In Formula 1, R1-R2 are the same or different and are independently selected from any one of the following structures: hydrogen, deuterium, cyano, halogen, an alkyl group having 1 to 10 carbon atoms which is unsubstituted or substituted by deuterium or halogen, an aryl group having 6 to 25 carbon atoms which is unsubstituted or substituted by at least one substituent selected from cyano, deuterium, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, or a deuterated alkyl group having 1 to 10 carbon atoms, and a heterocyclic aryl group having 3 to 20 carbon atoms which is unsubstituted or substituted by at least one substituent selected from cyano, deuterium, an alkyl group having 1 to 10 carbon atoms, or a deuterated alkyl group having 1 to 10 carbon atoms; In formula 1, n1-n2 are the same or different and are independently selected from 1 or 2; In formula 1 Represents an empty or single bond; when When it is empty, X1-X2 are the same or different and independently selected from any one of the following structures: O, S; When it represents a single bond, X1-X2 are the same or different and are independently selected from any one of the following structures: N(A3 or A4); In Formula 1, A3-A4 are the same or different and are independently selected from any one of the following structures: an aryl group having 6 to 25 carbon atoms which is unsubstituted or substituted with at least one substituent selected from cyano, deuterium, an alkyl group having 1 to 10 carbon atoms, and a deuterated alkyl group having 1 to 10 carbon atoms; or A3 and A1, A4 and A2 are the same or different and are connected by any one of a single bond, O, S, and C(R3)(R4) to form a large conjugated aromatic heterocyclic structure; In Formula 1, R3-R4 are the same or different and are selected from any one of the following structures: an alkyl group having 1 to 5 carbon atoms; In Formula 1, L1 is selected from any one of the following structures: a single bond, an aryl group having 6 to 25 carbon atoms which is unsubstituted or substituted with at least one substituent selected from cyano, deuterium, and an alkyl group having 1 to 10 carbon atoms, an N-containing heteroaryl group having 3 to 25 carbon atoms which is unsubstituted or substituted with at least one substituent selected from cyano, deuterium, and an alkyl group having 1 to 10 carbon atoms; In Formula 1, Ar1 is selected from any one of the following structures: a carbazolyl group substituted with at least one substituent selected from deuterium and an alkyl group having 1 to 10 carbon atoms; and the deuterium substitution ratio in Ar1 is above 80%.

2. A deuterated fused ring compound according to claim 1, characterized in that: In Formula 1, the structures of R1, R2, A3, and A4 are the same or different and are independently selected from any one of Formula 2 and Formula 3: m is selected from: 1, 2, 3; In formula 2, R 5a Any one selected from the following structures: hydrogen, deuterium, cyano, alkyl having 1 to 10 carbon atoms, halogenated alkyl having 1 to 10 carbon atoms, deuterated alkyl having 1 to 10 carbon atoms, phenyl, naphthyl, R 5a Connected by single bonds or through shared chemical bonds to form fused ring structures; Or the C atom in Formula 2 is replaced by a N atom to form the structure shown in Formula 2-1; In formula 3, R 5b Any one selected from the following structures: hydrogen, deuterium, cyano, an alkyl group having 1 to 10 carbon atoms, or a phenyl group substituted with deuterium, cyano, or an alkyl group having 1 to 10 carbon atoms; In formula 3, X3 is selected from any one of the following structures: O, S, N(R 5c ); In formula 3, R 5c Any one selected from the following structures: phenyl, biphenyl which is unsubstituted or substituted with at least one substituent selected from cyano, deuterium and an alkyl group having 1 to 10 carbon atoms.

3. A deuterated fused ring compound according to claim 1, characterized in that: The structure of Formula 1 is selected from any one of Formula 4 to Formula 7: X 4a , X 4b The same or different are independently selected from any one of the following structures: single bond, O, S, C(CH3)(CH3).

4. A deuterated fused ring compound according to claim 3, characterized in that: L1 in Formula 1, Formula 4 to Formula 7 is selected from any one of the following structures: a single bond, a phenyl group, a biphenyl group, or a naphthyl group that is unsubstituted or substituted with at least one substituent selected from a cyano group and an alkyl group having 1 to 5 carbon atoms.

5. A deuterated fused ring compound according to claim 3, characterized in that: A in Formula 1, Formula 4-Formula 7 r1 The structure is selected from any one of the following structures: a carbazolyl group substituted by a deuterated alkyl group having 1 to 5 carbon atoms; and the number of alkyl substitutions is 1-2, A r1 The deuterium substitution rate is 100%.

6. A deuterated fused ring compound according to claim 5, characterized in that: The structure of Ar1 is selected from any of the following:

7. A deuterated fused ring compound according to any one of claims 1 to 5, characterized in that: The structure of the deuterated fused ring compound is selected from any one of the following:

8. An organic electroluminescent device, comprising an anode, a cathode and an organic functional layer located between the anode and the cathode, characterized in that: The organic functional layer comprises at least one of the deuterated fused ring compounds according to any one of claims 1 to 7.

9. The organic electroluminescent device according to claim 8, characterized in that: The organic functional layer includes a light-emitting layer, and the light-emitting layer includes at least one of the deuterated fused-ring compounds.

10. The organic electroluminescent device according to claim 9, characterized in that: At least one of the deuterated fused ring compounds is used as a doping material, a co-dopant material or a host material in the light-emitting layer.

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