Blue luminescent composition and organic electroluminescent device comprising same

Abstract

Disclosed in the present invention are a blue luminescent composition and an organic electroluminescent device comprising same. The blue luminescent composition comprises a host material having a general structural formula as represented by formula (I) and a guest material having a general structural formula as represented by formula (II). In the present invention, a compound containing a dibenzofuran group and deuterium-substituted anthracene is used as the host material, and a compound containing a thiophene and other steric hindrance groups and a cycloalkyl is used as the guest material. The composition formed by means of reasonable combination can significantly enhance the stability and prolong the service life of a blue-light organic electroluminescent device and also improve the electron migration and transport efficiency, thereby eliminating the main body luminescence phenomenon.

Description

A blue luminescent composition and an organic electroluminescent device comprising the same. Technical Field

[0001] This invention belongs to the field of OLED technology, specifically including a blue light-emitting composition and an organic electroluminescent device containing the same. Background Technology

[0002] In recent years, optoelectronic devices based on organic materials have become increasingly popular. Examples of such organic optoelectronic devices include organic light-emitting diodes (OLEDs), organic field-effect transistors, organic photovoltaic cells, and organic sensors. Among them, OLEDs have developed particularly rapidly and have already achieved commercial success in the field of information display. OLEDs can provide highly saturated red, green, and blue colors, and full-color displays made with them do not require an additional backlight, offering advantages such as vibrant colors, short response time, wide color gamut, and high contrast.

[0003] OLED blue fluorescent devices employ a combination of host and guest materials. The host material is responsible for carrier transport and recombination to form excitons, and then transfers exciton energy to the guest material. The guest material, upon receiving energy from the host material, emits light within the target wavelength range. Sometimes, sensitizers are introduced to improve the energy transfer efficiency between the host and guest materials. Different host and guest materials have different energy transfer efficiencies; poor energy transfer can lead to decreased device performance. Furthermore, the energy transfer between the host and guest materials is also affected by their interactions. Currently, anthracene-based host materials are commonly used, with substituents typically being naphthalene-based fused-ring structures. Although some deuterium-substituted host material structures have been reported, due to the choice of substitution positions, they have not significantly improved the overall device performance, and the combination of host and guest materials has not fully utilized their interactions to achieve better functionality.

[0004] In addition, when there is a problem with poor energy transfer between the host and guest materials, deep blue light will appear in the 410-430nm region, which is the phenomenon of "host emission". See Figure 2 (the y-axis uses a logarithmic coordinate axis with a value range of 0.01 to 1). The generation of deep blue light can cause damage to the human eye and greatly reduce the efficiency of the device. This is another problem that needs to be solved in organic electroluminescent devices.

[0005] Therefore, adjusting the structural configuration of the host and guest materials and promoting their rational combination is essential for improving the performance of organic light-emitting devices.

[0006] Summary of the Invention

[0007] In view of the above-mentioned problems in the prior art, the present invention provides a blue luminescent composition and an organic electroluminescent device comprising the same.

[0008] To achieve the above objectives, the technical solution adopted by the present invention includes:

[0009] A first aspect of the present invention provides a blue luminescent composition comprising a compound of general structural formula as shown in Formula I and a compound of general structural formula as shown in Formula II:

[0010] In Formula I,

[0011] Ar1 represents one of the following: deuterated or unsubstituted phenyl, deuterated or unsubstituted naphthyl, deuterated or unsubstituted phenanthyl, or deuterated or unsubstituted pyrene.

[0012] L1 represents one of the following: a single bond, a deuterated or unsubstituted phenylene, or a deuterated or unsubstituted naphthylene.

[0013] Ar2 indicates

[0014] R 11 To R 14 R 21 To R 24 Each can be used independently to represent hydrogen or deuterium;

[0015] R 11 To R 14 R 21 To R 24 Any one of them is bonded to the anthracene structure of Formula I;

[0016] When the R 11 To R 14 When any one of them is selected from deuterium, the R 21 To R 24 Neither of them are selected from deuterium; when the R is mentioned 11 To R 14 When neither is selected from deuterium, the R 21 To R 24 At least one of them is selected from deuterium, and when the R 11 To R 14 R 21 To R 24 When any one of the hydrogen atoms is selected from deuterium, all hydrogen atoms belonging to the same benzene ring as it are replaced by deuterium;

[0017] In formula II,

[0018] Ring A represents a substituted or unsubstituted cycloalkyl group with 3 to 10 carbon atoms; L2 represents a single bond;

[0019] R1, R2, R3, and R5 each independently represent any one of the following: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl group with 1 to 30 carbon atoms, substituted or unsubstituted alkenyl group with 2 to 30 carbon atoms, substituted or unsubstituted cycloalkyl group with 3 to 30 carbon atoms, substituted or unsubstituted aryl group with 6 to 60 carbon atoms, substituted or unsubstituted heteroaryl group with 5 to 60 carbon atoms, substituted or unsubstituted fused-ring aryl group with 5 to 60 carbon atoms, substituted or unsubstituted heterofused-ring aryl group with 5 to 60 carbon atoms, or substituted or unsubstituted amino group; two or more R1, R2, R3, and R5 can each be linked to form a ring structure;

[0020] R4 represents any one of the following: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl group with 1 to 30 carbon atoms, substituted or unsubstituted alkoxy group with 1 to 30 carbon atoms, substituted or unsubstituted cycloalkyl group with 3 to 30 carbon atoms, substituted or unsubstituted aryl group with 6 to 60 carbon atoms, substituted or unsubstituted heteroaryl group with 5 to 60 carbon atoms, substituted or unsubstituted fused-ring aryl group with 5 to 60 carbon atoms, substituted or unsubstituted heterofused-ring aryl group with 5 to 60 carbon atoms, or substituted or unsubstituted amino group.

[0021] X represents O or S;

[0022] m, n, and q each independently represent 0, 1, 2, 3, or 4; when m is 2, 3, or 4, R1 can be the same or different; when n is 2, 3, or 4, R2 can be the same or different; when q is 2, 3, or 4, R5 can be the same or different.

[0023] p represents 0, 1, 2, 3, 4 or 5; when p is 2, 3, 4 or 5, R3 can be the same or different;

[0024] r represents 0 or 1;

[0025] The substituents in rings A, R1, R2, R3, R4, and R5 may be the same or different, and each may be independently selected from deuterium, halogen, cyano, alkyl with 1 to 10 carbon atoms, aryl with 6 to 60 carbon atoms, heteroaryl with 5 to 60 carbon atoms, fused aryl with 5 to 60 carbon atoms, cycloalkyl with 3 to 30 carbon atoms, and amino. Two or more substituents may be connected to each other to form an aliphatic ring, an aromatic ring, or a fused ring.

[0026] In Formulas I and II, any hydrogen atom can be replaced by deuterium, and any nitrogen atom can be replaced by deuterium. 15 N substitution, any sulfur can be... 33 S, 34 S or 36 S can be replaced, and any oxygen can be... 17 O or 18O can be substituted, any carbon can be... 13 C substitution, any boron can be... 11 B is replaced.

[0027] Furthermore, when L1 represents a single bond, Ar1 represents one of the following: a deuterated or unsubstituted phenyl group, a deuterated or unsubstituted naphthyl group, a deuterated or unsubstituted phenanthyl group, or a deuterated or unsubstituted pyrene group.

[0028] When L1 represents phenylene, Ar1 represents either phenyl or naphthyl.

[0029] When L1 represents a deuterated phenylene, Ar1 represents either a deuterated phenyl or a deuterated naphthyl.

[0030] When L1 represents naphthylene, Ar1 represents phenyl;

[0031] When L1 represents a deuterated naphthyl group, Ar1 represents a deuterated phenyl group.

[0032] Furthermore, the Ar2 is selected from one of the structures shown in formulas A-1 to A-8 below:

[0033] Wherein, * represents the site where Ar2 is bonded to the anthracene structure of Formula I.

[0034] Furthermore, the compound represented by Formula II is selected from any one of Formula II-1 to Formula II-4:

[0035] Furthermore, R1, R2, R3, and R5 each independently represent hydrogen, deuterium, substituted or unsubstituted alkyl with 1 to 10 carbon atoms, substituted or unsubstituted alkenyl with 2 to 10 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 10 carbon atoms, and substituted or unsubstituted aryl with 6 to 12 carbon atoms. Two or more R1, R2, R3, and R5 can each be connected to form a cyclic structure.

[0036] The R4 represents hydrogen, deuterium, substituted or unsubstituted alkyl with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 10 carbon atoms, or substituted or unsubstituted aryl with 6 to 12 carbon atoms.

[0037] The substituents in rings A, R1, R2, R3, R4, and R5 may be the same or different, and each may be independently selected from deuterium and alkyl groups having 1 to 10 carbon atoms.

[0038] Furthermore, the cycloalkyl group is cyclohexyl or cyclopentyl.

[0039] Furthermore, m, n, p, and q each independently represent 0, 1, or 2.

[0040] Furthermore, the compound represented by Formula I is selected from any one of the following compounds:

[0041] Furthermore, the compound represented by Formula II is selected from any one of the following compounds:

[0042] A second aspect of the present invention provides an organic electroluminescent device, comprising an anode, a hole transport region, a light-emitting layer, an electron transport region, and a cathode sequentially disposed on a substrate; wherein the light-emitting layer comprises one or more blue light-emitting compositions as described above.

[0043] Furthermore, the light-emitting layer comprises a host material and a guest material, wherein the host material comprises one or more compounds with a general structural formula as shown in Formula I, and the guest material comprises one or more compounds with a general structural formula as shown in Formula II.

[0044] Beneficial effects of this invention:

[0045] The blue light host material (BH) provided by this invention involves complete deuteration of the anthracene structure in the parent core, resulting in a reduction in the energy of the luminescent material and a significant enhancement in the stability and lifetime of the light-emitting device. Furthermore, the introduction of deuteration into the dibenzofuran structure and / or substituents such as phenyl, naphthyl, phenanthrene, and pyrene allows for a longer device lifetime without increasing voltage, reducing energy loss. The deuterated components can also interact with the cycloalkyl groups on the guest material, strengthening the dipole-dipole interaction between the host and guest materials, thereby improving exciton energy transfer. In the blue light guest material (BD) provided by this invention, the introduction of sterically hindered groups such as thiophene can suppress vibrations in the parent core, reducing energy loss and FWHM during excitation. Simultaneously, the introduction of cycloalkyl groups in the structure can generate steric interference, interfering with the encapsulation between guest materials, thus reducing light loss between guest materials and significantly improving efficiency.

[0046] This invention, through the rational combination of host and guest materials, using a highly polar host material and a guest material with good dispersion properties, can effectively avoid host luminescence and reduce concentration quenching. Therefore, by using the blue luminescent composition provided in this invention, the orientation of organic light-emitting materials can be improved, lifetime extended, and quenching reduced. Organic electroluminescent devices prepared using the blue luminescent composition of this invention exhibit excellent performance in external quantum efficiency, lifetime, and driving voltage. Attached Figure Description

[0047] Figure 1 is a schematic diagram of the structure of the organic electroluminescent device of the present invention;

[0048] Figure 2 shows a UV-PL image with host luminescence.

[0049] Figure description: 1-substrate, 2-anode, 3-hole injection layer, 4-hole transport layer, 5-light-emitting auxiliary layer, 6-light-emitting layer, 7-hole blocking layer, 8-electron transport layer, 9-electron injection layer, 10-cathode. Detailed Implementation

[0050] To better understand the content of this invention, a detailed description will be provided in conjunction with the accompanying drawings and embodiments.

[0051] The compounds of this invention are applicable to light-emitting elements, display panels, and electronic devices, particularly organic electroluminescent devices. The electronic devices described in this invention are devices comprising a layer of at least one organic compound, and may also comprise layers of inorganic materials or layers formed entirely of inorganic materials. Preferably, the electronic devices are organic electroluminescent devices (OLEDs), organic integrated circuits (O-ICs), organic field-effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors (O-LETs), organic solar cells (O-SCs), organic dye-sensitized solar cells (O-DSSCs), organic optical detectors, organic photosensors, organic field quenching devices (O-FQDs), light-emitting electrochemical cells (LECs), organic laser diodes (O-lasers), and organic plasma emitting devices. Organic electroluminescent devices (OLEDs) are particularly preferred. A schematic diagram of an exemplary organic electroluminescent device is shown in Figure 1.

[0052] Experimental Section

[0053] To better understand the content of this invention, the polycyclic compound, the preparation method of the compound, and the luminescent properties of the device will be explained in detail with reference to embodiments. Various chemical reactions can be applied to the synthesis method of the compound according to one embodiment of this invention. However, it should be noted that the synthesis method of the compound according to one embodiment of this invention is not limited to the synthesis method described below. Unless otherwise stated, subsequent synthesis is carried out in an anhydrous solvent under a protective gas atmosphere. Solvents and reagents can be purchased from conventional reagent suppliers.

[0054] Synthesis Example 1

[0055] This synthetic example provides a compound H-1, and the synthetic route of this compound is as follows:

[0056] In a 100 mL reaction flask, compound 1-g (1.29 g, 10 mmol), 10 mL D2O, 2 mL isopropanol, and 2 mL n-hexane were added. Under an argon atmosphere, Pt / C (1.0 g, 0.5 mmol) was added, the temperature was raised to 90 °C, and the reaction was carried out for 24 h. The mixture was then cooled to room temperature, and Pt / C was removed by filtration. 20 mL dichloromethane was added, the mixture was stirred, allowed to stand, and the phases were separated. The lower layer was dried with anhydrous sodium sulfate, filtered, and distilled under reduced pressure to obtain 1-f (0.96 g, yield: 72%).

[0057] In a 250 mL reaction flask, 1-f (1.33 g, 10 mmol), diisopropylamine (0.10 g, 1 mmol), and 20 mL of dichloromethane were added. N-bromosuccinimide (3.92 g, 22 mmol) was slowly added, the temperature was raised to 30 °C, and the reaction was carried out for 12 h. The temperature was then lowered to room temperature, and the pH of the system was adjusted to 5 with 1 mol / L hydrochloric acid solution. 20 mL of water was added, the mixture was stirred, allowed to stand, and the liquid was separated. The organic phase was collected, and the aqueous phase was extracted with 20 mL of dichloromethane. The organic phases were combined, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and passed through a silica gel column to obtain 1-e (1.30 g, yield: 62%).

[0058] In a 250 mL three-necked flask under nitrogen protection, 30 mL of toluene, 15 mL of ethanol, and 15 mL of water were added. Then, compound 1-e (2.10 g, 10 mmol), compound 1-d (1.40 g, 10 mmol), potassium carbonate (4.15 g, 30 mmol), and tetraphenylphosphine palladium (0.35 g, 0.3 mmol) were added. The mixture was heated to 80 °C and reacted for 12 h. After cooling to room temperature, 15 mL of water was added, the mixture was stirred, allowed to stand for separation, and the organic phase was evaporated to dryness under reduced pressure and passed through a silica gel column to obtain 1-c (1.67 g, yield: 74%).

[0059] In a 250 mL three-necked flask under nitrogen protection, 1-c (2.26 g, 10 mmol), potassium carbonate (4.15 g, 30 mmol), and 30 mL NMP were added. The mixture was heated to 120 °C and reacted for 16 h. After the reaction was completed, the mixture was cooled to room temperature, 40 mL of water was added, and the mixture was stirred and allowed to stand to separate into layers. The aqueous phase was extracted with 30 mL of ethyl acetate, and the organic phase was dried over anhydrous sodium sulfate. After filtration, the organic phase was evaporated to dryness under reduced pressure and passed through a silica gel column to obtain 1-b (1.46 g, yield: 71%).

[0060] Under nitrogen protection, 40 mL of 1,4-dioxane and 10 mL of water were added to a 250 mL three-necked flask. Then, 1-b (2.06 g, 10 mmol), 1-a (3.56 g, 10 mmol), potassium phosphate (6.37 g, 30 mmol), and tetraphenylphosphine palladium (0.35 g, 0.3 mmol) were added. The mixture was heated to 90 °C and reacted for 8 h. After the reaction was completed, the mixture was cooled to room temperature, and 40 mL of water and 30 mL of dichloromethane were added. The mixture was stirred and allowed to stand to separate into layers. The aqueous phase was extracted with 30 mL of dichloromethane, and the organic phases were combined. The organic phase was dried over anhydrous sodium sulfate, filtered, and distilled under reduced pressure. The solution was then passed through a silica gel column and recrystallized to give compound H-1 (3.18 g, yield: 66%), MS: m / z 481.24 [M+].

[0061] Synthesis Example 2

[0062] This synthetic example provides a compound H-2, and the synthetic route of this compound is as follows:

[0063] Following the synthetic method of compound 1-f, 1-g was replaced with 2-g (1.29g, 10mmol) to obtain compound 2-f (0.92g, yield: 69%).

[0064] In a 100 mL reaction flask, compound 2-f (1.33 g, 10 mmol), 20 mL of dichloromethane, and 1 mL of glacial acetic acid were added. The mixture was cooled to 0 °C, and bromine (1.60 g, 10 mmol) was slowly added dropwise. After the addition was complete, the mixture was stirred at 0 °C for 30 min, then brought to room temperature and reacted for 16 h. 30 mL of sodium thiosulfate solution was added, the mixture was stirred, and allowed to stand for phase separation. The aqueous phase was extracted with 20 mL of dichloromethane, and the organic phases were combined, dried over anhydrous sodium sulfate, filtered, and distilled under reduced pressure. The solution was then passed through a silica gel column to obtain 2-e (0.51 g, yield: 24%).

[0065] Following the synthetic method of compound 1-c, 1-e was replaced with 2-e (2.10 g, 10 mmol) and 1-d was replaced with 2-d (1.40 g, 10 mmol) to obtain compound 2-c (1.60 g, yield: 71%).

[0066] Following the synthetic method of compound 1-b, 1-c was replaced with 2-c (2.26 g, 10 mmol) to obtain compound 2-b (1.48 g, yield: 72%).

[0067] Following the synthetic method of compound H-1, 1-b was replaced with 2-b (2.06 g, 10 mmol) and 1-a was replaced with 2-a (3.63 g, 10 mmol) to obtain compound H-2 (3.32 g, yield: 68%), MS: m / z 488.28 [M+].

[0068] Synthesis Example 3

[0069] This synthetic example provides a compound H-3, and the synthetic route of this compound is as follows:

[0070] Following the synthetic method of compound H-1, 1-b was replaced with 2-b (2.06 g, 10 mmol) and 1-a was replaced with 3-a (4.43 g, 10 mmol) to obtain compound H-3 (3.70 g, yield: 65%), MS: m / z 568.34 [M+].

[0071] Synthesis Example 4

[0072] This synthetic example provides a compound H-4, and the synthetic route of this compound is as follows:

[0073] Following the synthetic method of compound 1-f, 1-g was replaced with 4-g (1.29g, 10mmol) to obtain compound 4-f (0.88g, yield: 66%).

[0074] In a 100 mL reaction flask, compound 4-f (1.33 g, 10 mmol), 20 mL of acetonitrile, and concentrated sulfuric acid (1.08 g, 11 mmol) were added. After stirring at room temperature for 5 min, NBS (1.96 g, 11 mmol) was slowly added. The reaction was carried out at room temperature for 3 h. 20 mL of water was added, and the aqueous phase was extracted three times with 30 mL of dichloromethane. The organic phases were combined, dried over anhydrous sodium sulfate, filtered, and distilled under pressure. The solution was passed through a silica gel column to obtain 4-e (1.60 g, yield: 76%).

[0075] Following the synthetic method of compound 1-c, 1-e was replaced with 4-e (2.10 g, 10 mmol) and 1-d was replaced with 4-d (1.40 g, 10 mmol) to obtain compound 4-c (1.65 g, yield: 73%).

[0076] Following the synthetic method of compound 1-b, 1-c was replaced with 4-c (2.26 g, 10 mmol) to obtain compound 4-b (1.46 g, yield: 71%).

[0077] Following the synthetic method of compound H-1, 1-b was replaced with 4-b (2.06 g, 10 mmol) and 1-a was replaced with 4-a (3.63 g, 10 mmol) to obtain compound H-4 (3.27 g, yield: 67%), MS: m / z 488.28 [M+].

[0078] Synthesis Example 5

[0079] This synthetic example provides a compound H-5, and the synthetic route of this compound is as follows:

[0080] Following the synthetic method of compound H-1, 1-b was replaced with 4-b (2.06 g, 10 mmol) and 1-a was replaced with 5-a (4.32 g, 10 mmol) to obtain compound H-5 (3.85 g, yield: 69%), MS: m / z 557.27 [M+].

[0081] Synthesis Example 6

[0082] This synthetic example provides a compound H-6, and the synthetic route of this compound is as follows:

[0083] In a 100 mL reaction flask, compound 6-h (1.42 g, 10 mmol) and 20 mL of tetrahydrofuran were added. Under nitrogen protection, the mixture was cooled to -40 °C, and 2 M n-butyllithium (10 mL, 20 mmol) was slowly added dropwise. After the addition was complete, the mixture was stirred for 1 h. Trimethyl borate (2.08 g, 20 mmol) was slowly added, and the mixture was stirred for 30 min. The mixture was then brought to room temperature and stirred for 2 h. The mixture was cooled to -10 °C, and 30 mL of dilute hydrochloric acid was slowly added. The mixture was brought to room temperature and stirred for 1 h. 30 mL of dichloromethane was added, and the mixture was stirred. The mixture was allowed to stand and the phases were separated. The aqueous phase was extracted with 20 mL of dichloromethane, and the organic phases were combined. The mixture was dried over anhydrous sodium sulfate, filtered, and then distilled under reduced pressure to obtain 6-g (1.52 g, yield: 82%).

[0084] Following the synthetic method of compound 1-c, 1-e was replaced with 6-g (1.85 g, 10 mmol) and 1-d was replaced with 6-f (1.75 g, 10 mmol) to obtain compound 6-e (1.76 g, yield: 75%).

[0085] In a 250 mL reaction flask, under nitrogen protection, 6-e (2.35 g, 10 mmol) and 25 mL of dichloromethane were added. The mixture was cooled to -78 °C, and BBr3 (10.02 g, 40 mmol) was slowly added. The mixture was then slowly heated to room temperature and reacted for 2 h. The reaction was terminated by adding saturated NaHCO3 solution. The pH was adjusted to approximately 7, and 20 mL of water was added. The mixture was stirred, allowed to stand, and separated. The organic phase was collected, and the aqueous phase was extracted with 30 mL of dichloromethane. The organic phases were combined, dried over sodium sulfate, filtered, and the solvent was removed under reduced pressure. The solution was then passed through a silica gel column to obtain 6-d (1.53 g, yield: 74%).

[0086] Following the synthetic method of compound 1-b, 1-c was replaced with 6-d (2.07 g, 10 mmol) to obtain compound 6-c (1.35 g, yield: 72%).

[0087] In a 100 mL reaction flask, compound 6-c (1.87 g, 10 mmol), 20 mL of tetrachloromethane, and triethylamine (1.52 g, 15 mmol) were added. Under nitrogen protection, the mixture was cooled to 0 °C, and trifluoromethanesulfonic anhydride (4.23 g, 15 mmol) was slowly added. The mixture was stirred for 30 min, then brought to room temperature and reacted for another 4 h. 30 mL of saturated ammonium chloride solution was added, and the mixture was stirred and allowed to stand for phase separation. The organic phase was then washed with 20 mL of copper sulfate solution and then with 20 mL of water. The organic phase was dried over anhydrous sodium sulfate, filtered, and then distilled under reduced pressure to obtain 6-b (2.52 g, yield: 79%).

[0088] Following the synthetic method of compound H-1, 1-b was replaced with 6-b (3.19 g, 10 mmol) and 1-a was replaced with 6-a (3.56 g, 10 mmol) to obtain compound H-6 (3.03 g, yield: 63%), MS: m / z 481.24 [M+].

[0089] Synthesis Example 7

[0090] This synthetic example provides a compound H-7, and the synthetic route of this compound is as follows:

[0091] Following the synthetic method of compound H-1, 1-b was replaced with 6-b (3.19 g, 10 mmol) and 1-a was replaced with 7-a (4.32 g, 10 mmol) to obtain compound H-7 (3.68 g, yield: 66%), MS: m / z 557.27 [M+].

[0092] Synthesis Example 8

[0093] This synthetic example provides a compound H-8, and the synthetic route of this compound is as follows:

[0094] In a 100 mL reaction flask, add 8-i (1.12 g, 10 mmol), 10 mL D2O, and 5 mL isopropanol. Under an argon atmosphere, add Pt / C (0.12 g, 0.06 mmol), heat to 180 °C, react for 12 h, cool to room temperature, filter to remove Pt / C, and distill under reduced pressure to obtain 8-h (0.85 g, yield: 73%).

[0095] Following the synthetic method of compound 6-b, 6-c was replaced with 8-h (1.16 g, 10 mmol) to obtain compound 8-g (2.04 g, yield: 82%).

[0096] In a 250 mL reaction flask under nitrogen protection, 35 mL of toluene, potassium acetate (1.96 g, 20 mmol), 8-g (2.48 g, 10 mmol), 8-f (3.05 g, 12 mmol), and palladium dichloride (0.07 g, 0.1 mmol) were added. The mixture was heated to reflux and reacted for 8 h. After cooling to room temperature, 20 mL of water was added, the mixture was stirred, allowed to stand for separation, and the organic phase was collected. The organic phase was evaporated to dryness under reduced pressure and passed through a silica gel column to obtain 8-e (1.63 g, yield: 72%).

[0097] Following the synthetic method of compound 1-c, 1-e was replaced with 8-e (2.26 g, 10 mmol) and 1-d was replaced with 8-d (2.07 g, 10 mmol) to obtain compound 8-c (1.68 g, yield: 74%).

[0098] Following the synthetic method of compound 1-b, 1-c was replaced with 8-c (2.27 g, 10 mmol) to obtain compound 8-b (1.45 g, yield: 70%).

[0099] Following the synthetic method of compound H-1, 1-b was replaced with 8-b (2.07 g, 10 mmol) and 1-a was replaced with 8-a (4.15 g, 10 mmol) to obtain compound H-8 (3.85 g, yield: 71%), MS: m / z 541.31 [M+].

[0100] Synthesis Example 9

[0101] This synthetic example provides a compound H-9, and the synthetic route of this compound is as follows:

[0102] Following the synthetic method of compound 1-c, 1-e was replaced with 8-e (2.26 g, 10 mmol) and 1-d was replaced with 9-d (2.07 g, 10 mmol) to obtain compound 9-c (1.63 g, yield: 72%).

[0103] Following the synthetic method of compound 1-b, 1-c was replaced with 9-c (2.27 g, 10 mmol) to obtain compound 9-b (1.41 g, yield: 68%).

[0104] Following the synthetic method of compound H-1, 1-b was replaced with 9-b (2.07 g, 10 mmol) and 1-a was replaced with 9-a (3.63 g, 10 mmol) to obtain compound H-9 (3.38 g, yield: 69%), MS: m / z 489.29 [M+].

[0105] Synthesis Example 10

[0106] This synthetic example provides a compound H-10, and the synthetic route of this compound is as follows:

[0107] Following the synthetic method of compound H-1, 1-b was replaced with 9-b (2.07 g, 10 mmol) and 1-a was replaced with 10-a (4.43 g, 10 mmol) to obtain compound H-10 (3.99 g, yield: 70%), MS: m / z 569.34 [M+].

[0108] Synthesis Example 11

[0109] This synthetic example provides a compound H-11, and the synthetic route of this compound is as follows:

[0110] Following the synthetic method of compound 1-c, 1-e was replaced with 8-e (2.26 g, 10 mmol) and 1-d was replaced with 11-d (2.07 g, 10 mmol) to obtain compound 11-c (1.70 g, yield: 75%).

[0111] Following the synthetic method of compound 1-b, 1-c was replaced with 11-c (2.27 g, 10 mmol) to obtain compound 11-b (1.47 g, yield: 71%).

[0112] Following the synthetic method of compound H-1, 1-b was replaced with 11-b (2.07 g, 10 mmol) and 1-a was replaced with 11-a (3.63 g, 10 mmol) to obtain compound H-11 (3.62 g, yield: 74%), MS: m / z 489.29 [M+].

[0113] Synthesis Example 12

[0114] This synthetic example provides a compound H-12, and the synthetic route of this compound is as follows:

[0115] Following the synthetic method of compound H-1, 1-b was replaced with 11-b (2.07 g, 10 mmol) and 1-a was replaced with 12-a (4.43 g, 10 mmol) to obtain compound H-12 (4.10 g, yield: 72%), MS: m / z 569.34 [M+].

[0116] Synthesis Example 13

[0117] This synthetic example provides a compound H-13, and the synthetic route of this compound is as follows:

[0118] Following the synthetic method of compound 1-c, 1-e was replaced with 8-e (2.26 g, 10 mmol) and 1-d was replaced with 13-d (2.07 g, 10 mmol) to obtain compound 13-c (1.68 g, yield: 74%).

[0119] Following the synthetic method of compound 1-b, 1-c was replaced with 13-c (2.27 g, 10 mmol) to obtain compound 13-b (1.41 g, yield: 68%).

[0120] Following the synthetic method of compound H-1, 1-b was replaced with 13-b (2.07 g, 10 mmol) and 1-a was replaced with 13-a (3.56 g, 10 mmol) to obtain compound H-13 (3.23 g, yield: 67%), MS: m / z 482.24 [M+].

[0121] Synthesis Example 14

[0122] Y-1 (10.10 g; 10 mmol) was added to tert-butylbenzene (125 ml), and then the mixture was cooled to 0 °C under nitrogen protection. 12.4 ml (21 mmol) of 1.7 M tert-butyllithium pentane solution was added, and the mixture was heated to 60 °C and stirred for 2 h. The mixture was then cooled to 0 °C, and 2.0 ml (21 mmol) of boron tribromide was added and stirred for 0.5 h. The mixture was then cooled to 0 °C, and 3.65 ml (21 mmol) of N,N-diisopropylethylamine was added. The mixture was heated to 60 °C and stirred for 2 h. After cooling to room temperature, the mixture was quenched with ice water and separated. The organic phase was filtered and dehydrated with anhydrous magnesium sulfate. After removing the organic solvent by rotary evaporation, the mixture was recrystallized to finally obtain compound Z-1 (0.85 g, yield: 9%), MS: m / z 938.48 [M+].

[0123] Synthesis Example 15

[0124] Following the synthetic method of compound Z-1, Y-1 was replaced with Y-2 (10.46 g, 10 mmol) to obtain compound Z-2 (1.07 g, yield: 11%), MS: m / z 974.63 [M+].

[0125] Synthesis Example 16

[0126] Following the synthetic method of compound Z-1, Y-1 was replaced with Y-3 (10.80 g, 10 mmol) to obtain compound Z-3 (1.01 g, yield: 10%), MS: m / z 1008.56 [M+].

[0127] Synthesis Example 17

[0128] Following the synthetic method of compound Z-1, Y-1 was replaced with Y-4 (9.48 g, 10 mmol) to obtain compound Z-4 (0.73 g, yield: 8%), MS: m / z 906.51 [M+].

[0129] Synthesis Example 18

[0130] Following the synthetic method of compound Z-1, Y-1 was replaced with Y-5 (9.58 g, 10 mmol) to obtain compound Z-5 (0.89 g, yield: 10%), MS: m / z 886.50 [M+].

[0131] Synthesis Example 19

[0132] Following the synthetic method of compound Z-1, Y-1 was replaced with Y-6 (10.88 g, 10 mmol) to obtain compound Z-6 (0.92 g, yield: 9%), MS: m / z 1016.62 [M+].

[0133] Synthesis Example 20

[0134] Following the synthetic method of compound Z-1, Y-1 was replaced with Y-7 (10.06 g, 10 mmol) to obtain compound Z-7 (0.94 g, yield: 10%), MS: m / z 934.54 [M+].

[0135] Synthesis Example 21

[0136] Following the synthetic method of compound Z-1, Y-1 was replaced with Y-8 (10.08 g, 10 mmol) to obtain compound Z-8 (0.84 g, yield: 9%), MS: m / z 936.52 [M+].

[0137] Synthesis Example 22

[0138] Following the synthetic method of compound Z-1, Y-1 was replaced with Y-9 (10.28 g, 10 mmol) to obtain compound Z-9 (1.05 g, yield: 11%), MS: m / z 956.58 [M+].

[0139] Synthesis Example 23

[0140] Following the synthetic method of compound Z-1, Y-1 was replaced with Y-10 (10.28 g, 10 mmol) to obtain compound Z-10 (1.05 g, yield: 11%), MS: m / z 956.52 [M+].

[0141] Composition properties

[0142] To illustrate the unique advantages of the composite materials selected in this invention in terms of host-guest interactions, the molecular structural properties of the host and guest materials were calculated. Using Gaussian 09W software, based on density functional theory (DFT) calculations (basis set level set to b3lyp / 6-31g(d), charge number 0), the molecular structure was geometrically optimized, and the dipole moments μ of the host material (BH) and guest material (BD) in their ground states were obtained. D μ A According to the probability formula for dipole-dipole interactions between subject and object:

[0143] Among them, R DA It is the distance between the host and the guest. Since the doping concentration is the same, it is assumed that the distance between the host and the guest is approximately the same. It is assumed that the host and the guest have the same orientation. The probability p of dipole-dipole interaction between the host and the guest is calculated.

[0144] To evaluate whether the device formed by the composition selected in this invention produces a host light emission phenomenon, the mass concentration ratio of the guest material doping was reduced to 1% according to the device preparation method, and the electroluminescence spectrum was tested. The vertical axis was logarithmically scaled, and the presence or absence of emission peaks was observed in the range of 400-440 nm to evaluate whether a host light emission phenomenon was produced.

[0145] The compositions of the present invention were tested using the methods described above. For comparison, BH-1 to BH-3 can be used as the host material, and BD-1 to BD-3 can be used as the guest material. The performance test results of the compositions are shown in Table 1 below:

[0146] Table 1. Results of composition performance tests

[0147] The results above show that the probability of dipole-dipole interaction between the host and guest materials provided by this invention is greater than 3.5. This is because the host material provided by this invention contains an asymmetric structure and polar groups, which significantly increases the dipole moment of the host material. The guest material provided by this invention contains benzothiophene fragments and cycloalkyl fragments, which ensures that its polarity is suitable, avoiding the influence of host forces being too small due to excessive polarity, and also preventing the increase of intermolecular aggregation due to excessive polarity.

[0148] Furthermore, it can be seen that the composition of the present invention does not exhibit host luminescence even at low doping ratios, indicating that there is good energy transfer between the host and guest components in the composition of the present invention, which is beneficial to improving efficiency.

[0149] OLED manufacturing and characterization

[0150] Device Examples

[0151] The organic electroluminescent device provided by the present invention includes an anode, a hole transport region, a light-emitting layer, an electron transport region, and a cathode sequentially disposed on a substrate.

[0152] Furthermore, the hole transport region includes a hole injection layer, a hole transport layer, and a light-emitting auxiliary layer; the electron transport region includes an electron transport layer and an electron injection layer.

[0153] Furthermore, the light-emitting layer is composed of a host material and a guest material, and the host material of the light-emitting layer can be composed of one molecular material or multiple molecular materials.

[0154] The composition described in this invention can be used in the light-emitting layer of the aforementioned organic electroluminescent device.

[0155] In this embodiment, the anode uses a commonly used anode material in the art, such as ITO, Ag, or their multilayer structures. The hole injection layer uses a commonly used hole injection material in the art, with F4TCNQ, HATCN, NDP-9, etc., added for doping. The hole transport layer uses a commonly used hole transport material in the art. The light-emitting layer uses the host and guest material composition provided by this invention. The electron transport layer uses a commonly used electron transport material in the art. The electron injection layer uses a commonly used electron injection material in the art, such as Liq, LiF, Yb, etc. The cathode uses a commonly used material in the art, such as metallic Al, Ag, or metal mixtures (Ag-doped Mg, Ag-doped Ca, etc.).

[0156] The electrode fabrication method and the deposition method of each functional layer in this embodiment are conventional methods in the art, such as vacuum thermal evaporation or inkjet printing, and will not be described in detail here. Only some process details and testing methods in the fabrication process are supplemented as follows:

[0157] Device Example 1

[0158] This embodiment provides a blue organic light-emitting diode (OLED), the fabrication method of which is as follows: First, a hole injection layer is formed on an ITO layer (anode) formed on a substrate by vacuum deposition of HTL-01 and p-dopant-01 (HTL-01 to p-dopant-01 mass ratio of 97:3) with a thickness of 10 nm; second, a hole transport layer is formed on the hole injection layer by vacuum deposition of HTL-01 with a thickness of 120 nm; and third, a B2O3 electron beam is formed on the hole transport layer by vacuum deposition with a thickness of 5 nm. A light-emitting auxiliary layer is formed by prime-01; then, a light-emitting layer is formed on the light-emitting auxiliary layer by vacuum deposition of a combination of H-4 and Z-6 with a thickness of 20 nm, wherein H-4 is the host material and Z-6 is the guest material, and the mass ratio of host material to guest material is 98:2; next, a hole-blocking layer is formed on the light-emitting layer by vacuum deposition of HBL-01 with a thickness of 5 nm; an electron transport layer is formed by vacuum deposition of a mixture of ET-01 and Liq (mass ratio of 1:1) with a thickness of 30 nm; then, an electron injection layer is formed on the electron transport layer by depositing LiF with a thickness of 0.2 nm; finally, an electron cathode is formed on the electron injection layer by depositing aluminum (Al) with a thickness of 150 nm, thus fabricating a blue organic light-emitting device.

[0159] Apart from the host and guest materials of the luminescent layer, the molecular structural formulas of the other layers are as follows:

[0160] Device Examples 2-38

[0161] Organic electroluminescent devices were fabricated using the compositions described in other embodiments of Table 1 using the above method. Blue organic electroluminescent devices Examples 2-38 were fabricated by replacing the host and guest material compositions shown in Table 1 with the compositions of H-4 and Z-6 in Device Example 1.

[0162] Device Comparison Examples 1-7

[0163] Organic electroluminescent devices were prepared by using the above method with the compositions described in the comparative examples in Table 1. Blue organic electroluminescent devices (Comparative Examples 1-7) were prepared by replacing the host and guest material compositions shown in the comparative examples in Table 1 with the compositions of H-4 and Z-6 in Device Example 1.

[0164] The OLED devices described above were tested using standard methods. For this purpose, J = 10 mA / cm² was used. 2 The driving voltage, luminance, electroluminescent current efficiency (in cd / A), and external quantum efficiency (EQE, in percentage) of the organic electroluminescent device were determined as a function of luminescence density from the current / voltage / luminescence density characteristic line (IVL characteristic line) exhibiting Lambertian emission characteristics. The lifetime LT was defined as the time after which, when operating at a constant current J, the luminance decreased from the initial luminance L0 to a specific proportion L1; for example, J = 50 mA / cm². 2 The statement L1 = 90% refers to a value of 50 mA / cm. 2 When operating below the threshold, the luminous intensity decreases to 90% of its initial value L0 after time LT. Similarly, J = 20 mA / cm² 2 L1 = 80% refers to 20 mA / cm 2 When operating below the threshold, the luminous intensity drops to 80% of its initial value L0 after time LT.

[0165] Table 2 summarizes the data for various OLED devices. The parameters of the examples and comparative examples are compared to demonstrate the performance data of the various OLED devices.

[0166] The testing instruments and methods used to perform performance testing on the OLED devices of the above embodiments and comparative examples are as follows:

[0167] Brightness was tested using a PhotoResearch PR-635 spectral scanner;

[0168] Current density and turn-on voltage: tested using a Keithley 2400 digital source meter;

[0169] Life test: The LT-96ch life test device was used.

[0170] The performance test results of the above devices are listed in Table 2.

[0171] Table 2 Performance test results of blue light devices

[0172] As can be seen from the device performance test results in Table 2 above, when the composition of the present invention is used in organic electroluminescent devices, the voltage of all devices decreases, and the efficiency and lifetime are significantly improved compared with the comparative example. This is because the present invention makes full use of the interaction between the host and guest materials and the combination of different host materials by rationally selecting the host and guest materials, so that the final device of the present invention exhibits significant advantages.

[0173] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A blue luminescent composition, characterized in that, The blue luminescent composition comprises compounds with general structural formulas as shown in Formula I and Formula II: In Formula I, Ar1 represents one of the following: deuterated or unsubstituted phenyl, deuterated or unsubstituted naphthyl, deuterated or unsubstituted phenanthyl, or deuterated or unsubstituted pyrene. L1 represents one of the following: a single bond, a deuterated or unsubstituted phenylene, or a deuterated or unsubstituted naphthylene. Ar2 indicates R 11 To R 14 R 21 To R 24 Each can be used independently to represent hydrogen or deuterium; R 11 To R 14 R 21 To R 24 Any one of them is bonded to the anthracene structure of Formula I; When the R 11 To R 14 When any one of them is selected from deuterium, the R 21 To R 24 Neither of them are selected from deuterium; when the R is mentioned 11 To R 14 When neither is selected from deuterium, the R 21 To R 24 At least one of them is selected from deuterium, and when the R 11 To R 14 R 21 To R 24 When any one of the hydrogen atoms is selected from deuterium, all hydrogen atoms belonging to the same benzene ring as it are replaced by deuterium; In formula II, Ring A represents a substituted or unsubstituted cycloalkyl group with 3 to 10 carbon atoms; L2 represents a single bond; R1, R2, R3, and R5 each independently represent any one of the following: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl group with 1 to 30 carbon atoms, substituted or unsubstituted alkenyl group with 2 to 30 carbon atoms, substituted or unsubstituted cycloalkyl group with 3 to 30 carbon atoms, substituted or unsubstituted aryl group with 6 to 60 carbon atoms, substituted or unsubstituted heteroaryl group with 5 to 60 carbon atoms, substituted or unsubstituted fused-ring aryl group with 5 to 60 carbon atoms, substituted or unsubstituted heterofused-ring aryl group with 5 to 60 carbon atoms, or substituted or unsubstituted amino group; two or more R1, R2, R3, and R5 can each be linked to form a ring structure; R4 represents any one of the following: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl group with 1 to 30 carbon atoms, substituted or unsubstituted alkoxy group with 1 to 30 carbon atoms, substituted or unsubstituted cycloalkyl group with 3 to 30 carbon atoms, substituted or unsubstituted aryl group with 6 to 60 carbon atoms, substituted or unsubstituted heteroaryl group with 5 to 60 carbon atoms, substituted or unsubstituted fused-ring aryl group with 5 to 60 carbon atoms, substituted or unsubstituted heterofused-ring aryl group with 5 to 60 carbon atoms, or substituted or unsubstituted amino group. X represents O or S; m, n, and q each independently represent 0, 1, 2, 3, or 4; when m is 2, 3, or 4, R1 can be the same or different; when n is 2, 3, or 4, R2 can be the same or different; when q is 2, 3, or 4, R5 can be the same or different. p represents 0, 1, 2, 3, 4 or 5; when p is 2, 3, 4 or 5, R3 can be the same or different; r represents 0 or 1; The substituents in rings A, R1, R2, R3, R4, and R5 may be the same or different, and each may be independently selected from deuterium, halogen, cyano, alkyl with 1 to 10 carbon atoms, aryl with 6 to 60 carbon atoms, heteroaryl with 5 to 60 carbon atoms, fused aryl with 5 to 60 carbon atoms, cycloalkyl with 3 to 30 carbon atoms, and amino. Two or more substituents may be connected to each other to form an aliphatic ring, an aromatic ring, or a fused ring. In Formulas I and II, any hydrogen atom can be replaced by deuterium, and any nitrogen atom can be replaced by deuterium. 15 N substitution, any sulfur can be... 33 S, 34 S or 36 S can be replaced, and any oxygen can be... 17 O or 18 O can be substituted, any carbon can be... 13 C substitution, any boron can be... 11 B is replaced.

2. The blue luminescent composition according to claim 1, characterized in that, When L1 represents a single bond, Ar1 represents one of the following: a deuterated or unsubstituted phenyl group, a deuterated or unsubstituted naphthyl group, a deuterated or unsubstituted phenanthyl group, or a deuterated or unsubstituted pyrene group. When L1 represents phenylene, Ar1 represents either phenyl or naphthyl. When L1 represents a deuterated phenylene, Ar1 represents either a deuterated phenyl or a deuterated naphthyl. When L1 represents naphthylene, Ar1 represents phenyl; When L1 represents a deuterated naphthyl group, Ar1 represents a deuterated phenyl group.

3. The blue luminescent composition according to claim 1, characterized in that, The Ar2 is selected from one of the structures shown in formulas A-1 to A-8 below: Wherein, * represents the site where Ar2 is bonded to the anthracene structure of Formula I.

4. The blue luminescent composition according to claim 1, characterized in that, The compound represented by Formula II is selected from any one of Formula II-1 to Formula II-4:

5. The blue luminescent composition according to claim 1 or 4, characterized in that, R1, R2, R3, and R5 each independently represent hydrogen, deuterium, substituted or unsubstituted alkyl with 1 to 10 carbon atoms, substituted or unsubstituted alkenyl with 2 to 10 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 10 carbon atoms, or substituted or unsubstituted aryl with 6 to 12 carbon atoms. Two or more R1, R2, R3, and R5 can be connected to form a ring structure. The R4 represents hydrogen, deuterium, substituted or unsubstituted alkyl with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 10 carbon atoms, or substituted or unsubstituted aryl with 6 to 12 carbon atoms. The substituents in rings A, R1, R2, R3, R4, and R5 may be the same or different, and each may be independently selected from deuterium and alkyl groups having 1 to 10 carbon atoms.

6. The blue luminescent composition according to claim 1 or 4, characterized in that, The cycloalkyl group is cyclohexyl or cyclopentyl.

7. The blue luminescent composition according to claim 1, characterized in that, The compound represented by Formula I is selected from any one of the following compounds:

8. The blue luminescent composition according to claim 1, characterized in that, The compound represented by Formula II is selected from any one of the following compounds:

9. An organic electroluminescent device, characterized in that, It includes an anode, a hole transport region, a light-emitting layer, an electron transport region, and a cathode sequentially disposed on a substrate; wherein the light-emitting layer includes one or more blue light-emitting compositions as described in any one of claims 1-8.

10. The organic electroluminescent device according to claim 9, characterized in that, The light-emitting layer comprises a host material and a guest material, wherein the host material comprises one or more compounds with a general structural formula as shown in Formula I, and the guest material comprises one or more compounds with a general structural formula as shown in Formula II.

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