A deuterated organic electroluminescent compound and display panel

Abstract

The present invention relates to a deuterated organic electroluminescent compound and a display panel, and to the technical field of optoelectronic materials. The deuterated organic electroluminescent compound has a structure shown in Formula 1: the present invention uses deuterium atoms to replace hydrogen atoms to optimize the energy level structure of a low-voltage luminescent material, significantly reducing the operating voltage of OLEDs, while improving the life and efficiency of the device; the introduction of deuterium not only reduces the energy required for exciton formation, but also optimizes the electron cloud distribution of the molecule, enhances the conversion from triplet to singlet, and improves the current efficiency; the device using the material provided by the present invention exhibits a purer spectrum, is suitable for high color gamut display, and performs well in high-end display screens in particular; the device, due to its stronger chemical bond stability and heat resistance, can maintain stable performance even under high temperature or long-term working environment, and effectively prolongs the life.

Description

Technical Field

[0001] The present invention relates to the technical field of optoelectronic materials, and in particular to a deuterated organic electroluminescent compound and a display panel. Background Art

[0002] In the multilayer design of organic electroluminescent devices (OLEDs), especially in the light-emitting layer (EML), the phenomenon of exciton quenching is one of the key factors that lead to the degradation of device performance. Considering that each luminescent material molecule in the EML can be regarded as a vibrating dipole, its efficiency in emitting light depends on the relationship between the direction of light emission and the direction of the dipole. Specifically, when the emission direction of light is perpendicular to the direction of the dipole, the light can escape more efficiently; on the contrary, if the emission direction of light is parallel to the direction of the dipole, the intensity of light will be significantly weakened. According to the actual calculation of the waveguide model (PWM), the direction of the dipole has an important influence on the emission intensity of light. Therefore, to improve the light output efficiency of OLEDs, one of the most critical methods is to adjust the transition dipole moment (TDM) of the OLED luminescent molecules so that its direction is consistent with the emission direction of light. In actual devices, the transition dipole moment of the luminescent molecules should be parallel to the plane of the ITO (indium tin oxide) substrate.

[0003] In traditional thermally activated delayed fluorescence (TADF) OLED devices, the light-emitting layer usually contains a host material and a guest TADF material. However, since the photons generated in the TADF process have a random emission direction, only those photons emitted perpendicular to the surface of the ITO transparent electrode are likely to escape to the outside of the device, and the remaining photons will experience multiple reflections in the waveguide mode inside the device and eventually be absorbed. In order to enhance the light extraction efficiency of OLEDs, a common method is to add a layer of light extraction film to the outer surface of the device, but this not only increases the manufacturing cost, but also fails to fundamentally solve the problem of internal light loss caused by random emission of photons. Therefore, finding a more effective way to directionally control the emission direction of photons has become the key to improving the external luminous efficiency of OLEDs. In view of this, the present invention provides a deuterated organic electroluminescent compound and a display panel. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a deuterated organic electroluminescent compound and a display panel.

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

[0006] In a first aspect, a deuterated organic electroluminescent compound is provided.

[0007] The structure shown in formula 1:

[0008]

[0009] In Formula 1, Ar1 is a structure shown in Formula 2:

[0010]

[0011] In formula 2, at least one of R1-R2 is C1-C 10 The remaining R1-R2 are selected from hydrogen or C1-C 10 Deuterated alkyl; in formula 2 is the connection site;

[0012] In formula 1, R3-R4 are the same or different and are independently selected from any one of the following structures: hydrogen, cyano, C1-C 10 Alkyl, halogenated C1-C 10 Alkyl, C6-C 20 Aryl, C3-C 20 Heteroaryl, deuterium, C1-C 10 Deuterated alkyl, C6-C 20 Deuterated aryl, C3-C 20 deuterated heteroaryl, cyano, halogen, deuterium, C1-C 10 Alkyl, C1-C 10 At least one C6-C 20 Aryl, C3-C 20 A heteroaryl group, formula 2;

[0013] In formula 1, L1 is selected from any one of the following structures: single bond, C6-C 10 Aryl, deuterated, cyano, C1-C 10 At least one C6-C 10 The aromatic group;

[0014] In Formula 1, X1-X2 are the same or different and are independently selected from any one of the following structures: O, S, N(R5); R5 is selected from any one of the following structures: unsubstituted or substituted with deuterium, cyano, C1-C 10 Alkyl, C1-C 10 Deuterated alkyl substituted C6-C 20 Aryl, unsubstituted or deuterated, cyano, C1-C 10 Alkyl, C1-C 10 Deuterated alkyl substituted C3-C 20 or when R5 is selected from: phenyl, biphenyl, deuterated, cyano, C1-C 10 Alkyl, C1-C 10When the phenyl or biphenyl group is substituted with a deuterated alkyl group, -X3- is connected to one or two of A1 and A2 to form a condensed ring structure; X3 is selected from any one of the following structures: O, S, C(CH3)(CH3), single bond.

[0015] Further, the structure of Ar1 in Formula 1 is selected from any one of the following:

[0016]

[0017] Further, when X1-X2 is N(R5), the structure of N(R5) is selected from any one of the following structures:

[0018]

[0019] In formula 3, R6 is selected from any one of the following structures: deuterium, hydrogen, cyano, C1-C 10 Alkyl, formula 2, phenyl, deuterated, cyano, C1-C 10 an alkyl-substituted phenyl group;

[0020] In formula 3-1, R 6a Any one of the following structures: deuterium, hydrogen, cyano, C1-C 10 Alkyl, phenyl, deuterated, cyano, C1-C 10 an alkyl-substituted phenyl group;

[0021] m is selected from: 1, 2, 3; when R6 is selected from C1-C 10 When the alkyl group is alkyl, m is selected from: 2, 3;

[0022] C1-C 10 The alkyl group is selected from any one of the following structures: methyl, ethyl, tert-butyl, n-propyl, isopropyl; C1-C 10 The alkyl group is selected from any one of the following structures: methyl, tert-butyl; C1-C 10 The structural definition of deuterated alkyl is similar to that of C1-C 10 The alkyl groups are the same;

[0023] In formula 4, A3 is selected from one or two of A1 and A2;

[0024] In formula 4, R7 is selected from any one of the following structures: hydrogen, cyano, C1-C 10 Alkyl, C6-C 10 Aryl, C1-C 10 Deuterated alkyl, C6-C 10 deuterated aryl, cyano, C1-C 10 Alkyl, C1-C 10 Deuterated alkyl substituted C6-C 10 Deuterated aryl, C6-C 10The aromatic group;

[0025] Further, R7 is selected from any one of the following structures: hydrogen, cyano, C1-C5 alkyl, phenyl, C1-C5 deuterated alkyl, deuterated phenyl, substituted by cyano, C1-C5 alkyl, C1-C5 deuterated alkyl, phenyl, deuterated phenyl;

[0026] In formula 4, X3 is selected from any one of the following structures: O, S, C(CH3)(CH3), and a single bond.

[0027] Further, R3-R4 are the same or different and are independently selected from any one of the following structures: phenyl, naphthyl, biphenyl, phenylnaphthyl, naphthylphenyl, phenyl substituted with deuterium, cyano, halogen, C1-C5 alkyl, C1-C5 deuterated alkyl, C1-C5 haloalkyl, C1-C5 deuterated haloalkyl; naphthyl, biphenyl, phenylnaphthyl, naphthylphenyl;

[0028] Alternatively, R3-R4 are the same or different and independently selected from any one of the following structures:

[0029]

[0030] In Formula 5, X4 is selected from any one of the following structures: CH, N, wherein at least one of X4 is N; further, Formula 5 is selected from any one of the following structures:

[0031] Furthermore, Formula 5 is selected from any one of the following structures:

[0032]

[0033] In Formula 6, X5 is selected from any one of the following structures: O, S, N, NH;

[0034] In Formula 6, R8-R9 are the same or different and are selected from any one of the following structures: hydrogen, cyano, C1-C5 alkyl, hexamembered aryl, C1-C5 deuterated alkyl, hexamembered deuterated aryl; for example, the C1-C5 alkyl can be: methyl, ethyl, tert-butyl, n-propyl, isopropyl; the C1-C5 deuterated alkyl can be: deuterated methyl, deuterated ethyl, deuterated tert-butyl, deuterated n-propyl, deuterated isopropyl, phenyl, deuterated phenyl.

[0035] Furthermore, Formula 6 is selected from any one of the following structures:

[0036]

[0037] Further, L1 is selected from any one of the following structures: a six-membered aromatic group, R 10 Selected from any one of the following structures: C1-C5 alkyl; n is 1-3.

[0038] Furthermore, the six-membered aryl group is a phenyl group;

[0039] Halogen is selected from any one of the following structures: fluorine, bromine;

[0040] C1-C 10 The alkyl group is selected from: C1-C8, C1-C6, C1-C5, C1-C4, C1-C3 alkyl groups; for example, methyl, ethyl, propyl, tert-butyl;

[0041] C6-C 20 The aryl group is selected from the group consisting of phenyl, naphthyl, biphenyl, phenylnaphthyl, naphthylphenyl;

[0042] C3-C 20 Heteroaryl: triazine, carbazolyl, dibenzothiophenyl, dibenzofuranyl, pyridyl.

[0043] Further, Formula 1 is selected from any one of the following structures:

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052] In a second aspect, a display panel includes a first electrode layer, a second electrode layer, and an organic functional layer disposed between the first electrode layer and the second electrode layer; the material of the organic functional layer includes at least one of the deuterated organic electroluminescent compounds. The display panel also includes a substrate, the first electrode layer is disposed on one side of the substrate, and the second electrode layer is disposed on the first electrode layer through the organic functional layer.

[0053] Furthermore, the organic functional layer includes a light-emitting layer, the light-emitting layer includes a host material and a guest material, and the guest material includes at least one of the deuterated organic electroluminescent compounds.

[0054] Furthermore, the light-emitting layer further includes a sensitizer, and the sensitizer is a thermally activated delayed fluorescent material.

[0055] The organic light-emitting material described in the present invention is a thermally activated delayed fluorescent material, and the thermally activated delayed fluorescent material comprises any one or a combination of at least two of the compounds described in one of the purposes.

[0056] When the deuterated organic electroluminescent compound provided by the present invention is used as a thermally activated delayed fluorescent material, ΔE≤0.36eV, so that reverse intersystem crossing is more likely to occur, and triplet excitons with a long lifetime are easily up-converted into singlet excitons, and the singlet excitons decay to the ground state S0 in the form of light radiation, resulting in a high photoinduced quantum yield PLQY, which can effectively reduce the roll-off effect, so that the device has good luminescence performance, and can be used as a doping material, a co-doping material or a main material of the light-emitting layer in an organic optoelectronic device.

[0057] Beneficial effects of the present invention:

[0058] (1) Compared with traditional luminescent materials, which require a higher driving voltage to overcome the energy level difference within the material to achieve effective recombination of electrons and holes, the deuterated organic electroluminescent compound provided by the present invention can effectively adjust the energy level structure of the molecule by replacing hydrogen atoms with deuterium atoms, reduce the energy required for exciton formation, and thus reduce the operating voltage of the device; when achieving the same brightness level, OLEDs using the luminescent compound provided by the present invention can operate at a lower voltage, which not only reduces energy consumption but also prolongs the service life of the device;

[0059] (2) The deuterated organic electroluminescent compound provided by the present invention, the introduction of deuterium optimizes the electron cloud distribution of the molecule, further enhances the conversion from triplet state to singlet state, and leads to higher current efficiency; in addition, the deuterated organic electroluminescent compound provided by the present invention can also show a purer blue spectrum, which can achieve high color gamut display, especially in high-end display screens that pursue true color reproduction;

[0060] (3) The deuterated organic electroluminescent compound provided by the present invention has stronger chemical bond stability and better heat resistance, and also has a longer life; it can maintain stable performance even under long-term continuous operation or high-temperature environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 This is the NMR image of Example 1 in the present invention. DETAILED DESCRIPTION

[0062] The embodiments of the present invention will be clearly and completely described below in conjunction with the examples, and the described examples are only some examples of the present invention, rather than all examples. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the examples in the present invention, all other examples obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0063] The reagents or instruments used in the present invention, if the manufacturer is not specified, are all conventional products that can be purchased from the market. For process parameters not specifically specified, conventional techniques can be used.

[0064] The following is a description of the preparation of the intermediates employed in Examples 1 to 20:

[0065] (1) Synthesis of intermediate 1:

[0066]

[0067] Feeding: 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 A1-1 (20 g), A1-2 (11.46 g), sodium carbonate (12.48 g) and tetrakistriphenylphosphine palladium (906.90 mg), react at 85°C for 12 hours under a nitrogen environment, monitor the reaction by TLC, and perform post-treatment after the reaction is completed;

[0068] Post-treatment: After the reaction is completed, 0.1 mol / L HCl is added to adjust the pH of the system to 6-7, water is added to separate, the organic phase is retained, the organic phase is spin-dried, ethanol is added and refluxed for 1 h, and after cooling to room temperature, the intermediate 1-A1-3 (18.96 g, HPLC shows purity 99%+) is obtained by filtration and drying;

[0069] The sample was sent to MS, and MS showed: 298.5142 (MS+1);

[0070] (2) Synthesis of intermediate 2:

[0071]

[0072] Referring to the synthesis method of intermediate 1, A1-1 in intermediate 1 was replaced with (9H-carbazole-3-yl)boric acid, the feed ratio of A1-2 was changed to 1eq, the feed ratio of sodium carbonate was changed to 1.5eq, and the feed ratio of tetrakistriphenylphosphine palladium was changed to 0.01eq, and the rest of the feeding method, post-treatment, etc. were the same.

[0073] MS (MS+1) shows: 233.4571.

[0074] (3) Synthesis of intermediate 3:

[0075]

[0076] Referring to the synthesis method of intermediate 1, A1-1 in intermediate 1 was replaced with (9H-carbazole-3-yl)boric acid, A1-2 was replaced with methyl bromide-D3, the feed ratio of A1-2 was changed to 1eq, the feed ratio of sodium carbonate was changed to 1.5eq and the feed ratio of tetrakistriphenylphosphine palladium was changed to 0.01eq, and the rest of the feeding method, post-treatment, etc. were the same.

[0077] MS (MS+1) shows: 185.6855.

[0078] (4) Synthesis of intermediate 4:

[0079]

[0080] Referring to the synthesis method of intermediate 1, A1-2 in intermediate 1 was replaced with methyl bromide-D3, and the rest of the feeding method, post-treatment, etc. were the same.

[0081] MS (MS+1) shows: 202.8748.

[0082] (5) Synthesis of intermediate 5:

[0083]

[0084] Referring to the synthesis method of intermediate 1, A1-1 in intermediate 1 was replaced with (9H-carbazole-1,8-diyl)diboric acid, and the rest of the feeding method, post-treatment, etc. were the same.

[0085] MS (MS+1) shows: 202.8504.

[0086] (6) Synthesis of intermediate 6:

[0087]

[0088] At room temperature, A2-2 (32.69 g), cesium carbonate (67.53 g), and A2-1 (20.00 g) were added to N-methyl-2-pyrrolidone (300 mL) in a nitrogen atmosphere, and the mixture was stirred and heated at 120°C for 18 hours. 0.1 mol / L hydrochloric acid was added to the reaction solution at 0°C to adjust the pH to neutral, and toluene was added to extract repeatedly 3 times, and the obtained organic layer was washed with water to remove N-methyl-2-pyrrolidone. The solvent was evaporated under reduced pressure to obtain a crude product, which was then purified by silica gel column chromatography to obtain intermediate 6 (A2-3) (38.58 g).

[0089] MS (MS+1) shows: 453.8510.

[0090] (7) Synthesis of intermediate 7:

[0091]

[0092] Referring to the synthesis method of intermediate 6, A2-2 in intermediate 1 was replaced with 4'-hydroxy-[1,1'-biphenyl]-4-carbonitrile, and the rest of the feeding method, post-treatment, etc. were the same.

[0093] MS (MS+1) shows: 543.4175.

[0094] (8) Synthesis of intermediate 8:

[0095]

[0096] Referring to the synthesis method of intermediate 6, A2-1 in intermediate 1 was replaced by 1-bromo-3,5-difluorobenzene-2,4,6-d3, and A2-2 was replaced by phenol-D5-ol. The rest of the feeding method, post-treatment, etc. were the same.

[0097] MS (MS+1) shows: 354.0673.

[0098] (9) Synthesis of intermediate 9:

[0099]

[0100] Add 300 ml of dry 1,4-dioxane mixed solution into a three-necked flask, flush with nitrogen for 5 minutes to replace the air in the system, add A3-1 (20 g), A3-2 (39.97 g), dry sodium tert-butoxide (18.32 g), PD2(DBA)3 (1.16 g), tri-tert-butyl phosphine (38.56 g), react at 100 ° C for 12 hours under nitrogen environment, 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 intermediate 9 (A3-3) (35.41).

[0101] MS (MS+1) shows: 691.5153.

[0102] (10) Synthesis of intermediate 10:

[0103]

[0104] Add 300 ml of dry 1,4-dioxane mixed solution to a three-necked flask, flush with nitrogen for 5 minutes to replace the air in the system, add A4-1 (20 g), A4-2 (9.35 g), dry sodium tert-butoxide (7.97 g), PD2(DBA)3 (0.5 g), tri-tert-butyl phosphine (16.78 g), react at 100 ° C for 12 hours under nitrogen environment, 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 intermediate A4-3 (16.80 g);

[0105] Add 300 ml of dry 1,4-dioxane mixed solution to a three-necked flask, flush with nitrogen for 5 minutes to replace the air in the system, add A4-3 (16.80 g), A4-4 (7.46 g), dry sodium tert-butoxide (6.01 g), PD2(DBA)3 (0.3 g), tri-tert-butyl phosphine (12.65 g), react at 100 ° C for 12 hours under nitrogen environment, 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 intermediate 10A4-5 (15.93);

[0106] MS (MS+1) shows: 445.3127.

[0107] (11) Synthesis of intermediate 11:

[0108]

[0109] Referring to the synthesis method of intermediate 10, A4-2 in intermediate 1 was replaced with 3,7-bis(methyl-d3)-10H-phenothiazine, and A4-4 was replaced with 3,7-bis(methyl-d3)-10H-phenoxazine. The rest of the feeding method, post-treatment, etc. were the same.

[0110] MS (MS+1) shows: 543.5411.

[0111] Embodiment 1:

[0112] The synthesis method of B1-4 comprises the following steps:

[0113]

[0114] Add 200 ml of dry 1,4-dioxane mixed solution 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 (17.44 g), dry sodium tert-butoxide (5.45 g), PD2(DBA)3 (0.5 g), tri-tert-butyl phosphine (17.79 g), react at 100 ° C for 12 hours under 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, and dry to obtain B1-3 (27.52 g).

[0115] Under nitrogen atmosphere, add 1.6 mol / L hexane solution (48.3 ml) of n-butyl lithium to a flask containing B1-3 (27.52 g) and xylene (300 ml). After the addition is complete, raise the temperature to 70°C and stir for 4 h, then heat to 100°C, distill off the hexane, cool to -50°C, add boron tribromide (12.36 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 h. After cooling to room temperature, add sodium acetate aqueous solution and toluene for separation, distill off the solvent under reduced pressure, spin dry, add the solid to 50 ml ethanol and reflux for 1 h, cool to room temperature, filter out the solid, spin dry to obtain 21.40 g of compound 1 shown in Example 1 ( Figure 1 ).

[0116] Embodiment 2-18:

[0117] Referring to the synthesis method of Example 1, B1-1 and B1-2 in Example 1 are replaced, and the rest of the feeding method, post-treatment, etc. are the same, to obtain Examples 2 to 18. The specific structures of B1-1 and B1-2 are shown in Table 1.

[0118] Table 1

[0119]

[0120]

[0121]

[0122]

[0123] Embodiment 19:

[0124] The synthesis method of B2-5 comprises the following steps:

[0125]

[0126] Add 200 ml of dry 1,4-dioxane mixed solution into a three-necked flask, flush with nitrogen for 5 minutes to replace the air in the system, add B2-1 (20 g), p-bromoiodophenylboric acid (19.02 g), sodium tert-butoxide (9.69 g), PD2(DBA)3 (0.6 g), tri-tert-butyl phosphine (20.40 g), react at 100 ° C for 12 hours under a nitrogen environment, and 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 the intermediate 9-(4-bromophenyl)-3,6-bis(2-(methyl-d3)propan-2-yl-1,1,3,3-d6)-9H-carbazole (25.57 g).

[0127] In a three-necked flask, 9-(4-bromophenyl)-3,6-bis(2-(methyl-d3)propan-2-yl-1,1,3,3-d6)-9H-carbazole (25.57 g) was added and dissolved in 200 mL of anhydrous THF. 3.80 g of n-butyl lithium was injected at -78°C. After reacting for 1 hour, 6.46 g of anhydrous trimethyl borate was injected and reacted for 12 hours. Water was added to quench the reaction, and the mixture was extracted with dichloromethane, dried, and recrystallized from n-hexane to obtain B2-2 (21.01 g).

[0128] 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 (21.01 g), B2-3 (26.95 g), sodium tert-butoxide (7.26 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 (35.14 g).

[0129] Under nitrogen atmosphere, add 1.6 mol / L hexane solution (48.3 ml) of n-butyl lithium to a flask containing B2-4 (35.14 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 (9.82 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 of ethanol and reflux for 1 hour, cool to room temperature, filter out the solid, spin dry to obtain 28.40 g of the compound shown in Example 19.

[0130] Embodiment 20:

[0131] Referring to the synthesis method of Example 19, B2-1 and B2-3 in Example 1 are replaced, and the rest of the feeding method, post-treatment, etc. are the same to obtain Example 20. The specific structures of B2-1 and B2-3 are shown in Table 2.

[0132] Table 2

[0133]

[0134] Comparative Examples 1-3

[0135] The compounds used in Comparative Examples 1-3 are shown in Table 3.

[0136] Table 3

[0137]

[0138]

[0139] Test example

[0140] 1. Performance test of compound monomers:

[0141] (1) ΔE ST : By mixing the compound at 10 -4 The sample was dissolved in toluene solution at 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 high-sensitivity integrated fluorescence spectrometer. The results are shown in Table 5.

[0142] (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 -5The sample was dissolved in toluene solution with a concentration of 1.5 mol / L and tested using a high-sensitivity integrated fluorescence spectrometer; the results are shown in Table 5.

[0143] (3) Delayed fluorescence lifetime: The compound was doped into polystyrene at a concentration of 1 wt % to prepare a test sample, and the test was performed using a time-resolved fluorescence spectrometer; the results are shown in Table 5.

[0144] (4) Mass spectrometry and HPLC test data of Examples 1 to 20. The results are shown in Table 4.

[0145] Table 4

[0146]

[0147]

[0148] Table 5

[0149] Serial number Compound Name <![CDATA[ΔE ST (eV)]]> Delayed fluorescence lifetime (μs) Half peak width (nm) 1 Example 1 0.17 105 42 2 Example 2 0.16 110 40 3 Example 3 0.12 95 32 4 Example 4 0.11 98 31 5 Example 5 0.15 100 38 6 Example 6 0.14 115 41 7 Example 7 0.13 102 33 8 Example 8 0.14 97 34 9 Example 9 0.12 103 32 10 Example 10 0.11 108 31 11 Embodiment 11 0.13 99 33 12 Example 12 0.16 95 37 13 Example 13 0.15 107 40 14 Embodiment 14 0.17 112 43 15 Embodiment 15 0.18 104 44 16 Example 16 0.14 109 35 17 Embodiment 17 0.16 118 39 18 Embodiment 18 0.15 90 36 19 Embodiment 19 0.12 101 32 20 Embodiment 20 0.17 120 45 21 Comparative Example 1 0.34 61 56 22 Comparative Example 2 0.26 83 49 23 Comparative Example 3 0.29 79 53

[0150] 2. Performance test of devices prepared using the compounds provided by the present invention (including comparative examples) 2.1 Preparation of devices

[0151] (1) Device 1

[0152] The preparation of device 1 comprises the following steps:

[0153] 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.

[0154] ② On the surface where the ITO film is formed, vacuum evaporate molybdenum trioxide (MoO3) to form a 10nm thick hole injection layer;

[0155] ③ On the hole injection layer, vacuum evaporate N,N'-diphenyl-N,N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine (NPB) to form a 60 nm thick hole transport layer;

[0156] ④ On the hole transport layer, 4,4',4"-tri(carbazole-9-yl)triphenylamine (TCTA) was vacuum-deposited to form a 10 nm electron blocking layer.

[0157] ⑤ On the electron blocking layer, 9,10-di(2-naphthyl)anthracene (ADN) (as a light-emitting host material, 95 wt%) and the compound 2 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 with a thickness of 30 nm;

[0158] ⑥ On the above-mentioned light-emitting layer, 1,3,5-tri(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi) was vacuum-deposited to form an electron transport layer with a thickness of 30 nm;

[0159] ⑦ On the electron transport layer, lithium fluoride (LiF) is vacuum evaporated to form an electron injection layer with a thickness of 1 nm;

[0160] ⑧Finally, magnesium-silver alloy (Mg / Ag) is vacuum-deposited on the electron injection layer to form a 100nm cathode.

[0161] (2) Preparation of Devices 2 to 20

[0162] An organic electroluminescent device was prepared in the same manner as device 1, except that the compounds synthesized in Synthesis Example 2 to Synthesis Example 20 were used to replace the compound prepared in Synthesis Example 1.

[0163] (3) Comparative Device 1 to Comparative Device 3

[0164] An organic electroluminescent device was prepared in the same manner as device 1, except that the compounds prepared in Synthesis Example 1 were replaced by the above-mentioned compounds of Comparative Examples 1 to Comparative Example 3, respectively.

[0165] 2.2 Driving voltage, color coordinates, current efficiency, LT95 test

[0166] 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 6.

[0167] Table 6

[0168]

[0169] 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 organic electroluminescent compound, characterized in that: The deuterated organic electroluminescent compound has a structure shown in Formula 1: In Formula 1, Ar1 is a structure shown in Formula 2: In formula 2, at least one of R1-R2 is C1-C 10 The remaining R1-R2 are selected from hydrogen or C1-C 10 Deuterated alkyl; in formula 2 is the connection site; In formula 1, R3-R4 are the same or different and are independently selected from any one of the following structures: hydrogen, cyano, C1-C 10 Alkyl, halogenated C1-C 10 Alkyl, C6-C 20 Aryl, C3-C 20 Heteroaryl, deuterium, C1-C 10 Deuterated alkyl, C6-C 20 Deuterated aryl, C3-C 20 deuterated heteroaryl, cyano, halogen, deuterium, C1-C 10 Alkyl, C1-C 10 At least one C6-C 20 Aryl, C3-C 20 A heteroaryl group, formula 2; In formula 1, L1 is selected from any one of the following structures: single bond, C6-C 10 Aryl, deuterated, cyano, C1-C 10 At least one C6-C 10 The aromatic group; In Formula 1, X1-X2 are the same or different and are independently selected from any one of the following structures: O, S, N(R5); R5 is selected from any one of the following structures: unsubstituted or substituted with deuterium, cyano, C1-C 10 Alkyl, C1-C 10 Deuterated alkyl substituted C6-C 20 Aryl, unsubstituted or deuterated, cyano, C1-C 10 Alkyl, C1-C 10 Deuterated alkyl substituted C3-C 20 or R5 is selected from: unsubstituted or deuterated, cyano, C1-C 10 Alkyl, C1-C 10 Deuterated alkyl substituted C6-C 20 An aryl group is connected to one or both of A1 and A2 through -X3- to form a condensed ring structure; X3 is selected from any one of the following structures: O, S, C(CH3)(CH3), a single bond.

2. A deuterated organic electroluminescent compound according to claim 1, characterized in that: The structure of Ar1 in Formula 1 is selected from any one of the following:

3. A deuterated organic electroluminescent compound according to claim 1, characterized in that: When X1-X2 is N(R5), the structure of N(R5) is selected from any one of the following structures: In formula 3, R6 is selected from any one of the following structures: deuterium, hydrogen, cyano, C1-C 10 Alkyl, formula 2, phenyl, deuterated, cyano, C1-C 10 an alkyl-substituted phenyl group; In formula 3-1, R 6a Any one of the following structures: deuterium, hydrogen, cyano, C1-C 10 Alkyl, phenyl, deuterated, cyano, C1-C 10 an alkyl-substituted phenyl group; m is selected from: 1, 2, 3; In formula 4, A3 is selected from one or two of A1 and A2; In formula 4, R7 is selected from any one of the following structures: hydrogen, cyano, C1-C 10 Alkyl, C6-C 10 Aryl, C1-C 10 Deuterated alkyl, C6-C 10 deuterated aromatic groups, cyano, C1-C 10 Alkyl, C1-C 10 At least one C6-C 10 Deuterated aryl or C6-C 10 The aromatic group; In formula 4, X3 is selected from any one of the following structures: O, S, C(CH3)(CH3), and a single bond.

4. A deuterated organic electroluminescent compound according to claim 1, characterized in that: R3-R4 are the same or different and independently selected from any one of the following structures: phenyl, naphthyl, biphenyl, phenylnaphthyl, naphthylphenyl, phenyl substituted with deuterium, cyano, halogen, C1-C5 alkyl, C1-C5 deuterated alkyl, C1-C5 haloalkyl, C1-C5 deuterated haloalkyl; naphthyl, biphenyl, phenylnaphthyl, naphthylphenyl; Alternatively, R3-R4 are the same or different and independently selected from any one of the following structures: In Formula 5, X4 is selected from any one of the following structures: CH, N, wherein at least one of X4 is N; In Formula 6, X5 is selected from any one of the following structures: O, S, N, NH; In Formula 6, R8-R9 are the same or different and are selected from any one of the following structures: hydrogen, cyano, C1-C5 alkyl, hexamembered aryl, C1-C5 deuterated alkyl, hexamembered deuterated aryl.

5. A deuterated organic electroluminescent compound according to any one of claims 1 to 4, characterized in that: L1 is selected from any one of the following structures: a six-membered aromatic group, R 10 Selected from any one of the following structures: C1-C5 alkyl; n is 1-3.

6. A deuterated organic electroluminescent compound according to any one of claims 1 to 5, characterized in that: C6-C 20 The aryl group is selected from the group consisting of phenyl, naphthyl, biphenyl, phenylnaphthyl, naphthylphenyl; C3-C 20 Heteroaryl: triazine, carbazolyl, dibenzothiophenyl, dibenzofuranyl, pyridyl.

7. A deuterated organic electroluminescent compound according to claim 1, characterized in that: Formula 1 is selected from any one of the following structures:

8. A display panel, characterized in that: The invention comprises a first electrode layer, a second electrode layer and an organic functional layer arranged between the first electrode layer and the second electrode layer; the material of the organic functional layer comprises at least one of the deuterated organic electroluminescent compounds described in any one of claims 1 to 7.

9. The display panel according to claim 8, characterized in that: The organic functional layer comprises a light-emitting layer, the light-emitting layer comprises a host material and a guest material, and the guest material comprises at least one of the deuterated organic electroluminescent compounds.

10. The display panel according to claim 8, characterized in that: The light-emitting layer further includes a sensitizer, which is a thermally activated delayed fluorescent material.

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