Compound, organic electroluminescent device and display device

Abstract

The invention provides a compound, an organic electroluminescent device and a display device, and relates to the technical field of display. The structure of the compound is shown as a chemical formula 1, and the performance of the organic electroluminescent device can be improved when the compound is applied to the organic electroluminescent device.

Description

Technical Field

[0001] This disclosure relates to the field of display technology, and more specifically, to a compound, an organic electroluminescent device, and a display apparatus. Background Technology

[0002] OLED (Organic Light Emitting Diode) is an electroluminescent device widely used in solid-state lighting and displays due to its advantages such as self-emission, high resolution, low power consumption, high color saturation, wide color gamut, fast screen response, and flexibility. The rapid popularization of OLEDs, huge market demand, and the rapid iteration of electronic products have driven the research and development of functional materials, including hole injection materials, hole transport materials, hole blocking materials, light-emitting host materials, light-emitting dopants, electron blocking materials, electron transport materials, and electron injection materials, aiming to improve the performance of OLED devices such as luminous efficiency, driving voltage, lifetime, and color purity. Developing more compounds suitable for OLEDs is of great significance for promoting the further development and application of OLEDs.

[0003] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] The purpose of this disclosure is to overcome the shortcomings of the prior art and provide a compound, an organic electroluminescent device, and a display device to improve the performance of organic electroluminescent devices.

[0005] According to one aspect of this disclosure, a compound is provided having the structural formula shown in Chemical Formula 1:

[0006]

[0007] Wherein, L1 and L2 are each independently selected from single bonds or linking groups, and the linking group is selected from divalent arylene or divalent heteroarylene;

[0008] Q is an aryl group with 2 to 5 fused rings, substituted or unsubstituted; or a heteroaryl group with 2 to 5 fused rings, substituted or unsubstituted.

[0009] R1 to R3 may be the same as or different from each other, and each is independently selected from the group consisting of deuterium, fluorine, chlorine, substituted or unsubstituted alkyl with 1 to 12 carbon atoms, substituted or unsubstituted haloalkyl with 1 to 12 carbon atoms, substituted or unsubstituted alkoxy with 1 to 12 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 10 carbon atoms, substituted or unsubstituted aryl with 6 to 60 carbon atoms, and substituted or unsubstituted heteroaryl with 3 to 60 carbon atoms;

[0010] R4 is selected from deuterium, halogen groups, cyano, substituted or unsubstituted alkylamine group with 1 to 20 carbon atoms, substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group with 1 to 20 carbon atoms, substituted or unsubstituted aryloxy group with 6 to 30 carbon atoms, substituted or unsubstituted aryl group with 6 to 30 carbon atoms, and substituted or unsubstituted heterocyclic group with 5 to 30 carbon atoms.

[0011] a1 is an integer from 0 to 4; when a1 is greater than 1, any two R1s are the same or different.

[0012] a2 is an integer from 0 to 4; when a2 is greater than 1, any two R2 values ​​are the same or different.

[0013] a3 is an integer from 0 to 3; when a3 is greater than 1, any two R3s are the same or different;

[0014] a4 is an integer from 0 to 8; when a4 is greater than 1, any two R4s are the same or different.

[0015] According to another aspect of this disclosure, an organic electroluminescent device is provided, having an anode, an organic light-emitting layer, and a cathode sequentially stacked; the organic light-emitting layer comprising the aforementioned compound.

[0016] According to another aspect of this disclosure, a display device is provided, including the above-described organic electroluminescent device.

[0017] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0019] Figure 1 The diagram shows the raw materials and yields for the preparation of some compounds.

[0020] Figure 2 The diagram shows the raw materials and yields for the preparation of some compounds.

[0021] Figure 3 To simulate the electron cloud distribution of some compounds using molecular simulation software.

[0022] Figure 4The graph shows the performance parameters of some compounds.

[0023] Figure 5 The graph shows the performance parameters of some compounds.

[0024] Figure 6 This is a schematic diagram of the structure of an organic electroluminescent device according to one embodiment of the present disclosure. Detailed Implementation

[0025] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore detailed descriptions of them will be omitted. Furthermore, the drawings are merely illustrative of this disclosure and are not necessarily drawn to scale.

[0026] The terms “a,” “one,” “the,” “the,” and “at least one” are used to indicate the existence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first,” “second,” etc. are used only as markers and are not a limitation on the number of objects.

[0027] In this disclosure, the descriptive phrase "...each independently selected" should be interpreted broadly. It can mean either that the specific options expressed by the same symbol in different groups do not affect each other, or that the specific options expressed by the same symbol in the same group do not affect each other. For example, " In this context, each q' is independently 0, 1, 2, or 3, and each R" is independently selected from deuterium, fluorine, and chlorine. The meaning is as follows: Formula Q-1 indicates that there are q' substituents R" on the benzene ring. Each R" can be the same or different, and the options for each R" do not affect each other. Formula Q-2 indicates that there are q' substituents R" on each benzene ring of biphenyl. The number of substituents q' on the two benzene rings can be the same or different, and each R" can be the same or different. The options for each R" do not affect each other.

[0028] In this disclosure, a non-positioned linker bond refers to a single bond extending from the ring system. This means that one end of the linking bond can connect to any feasible position in the ring system that the bond penetrates, and the other end connects to the rest of the compound molecule.

[0029] For example, as shown in equation (f) below, the naphthyl group represented by equation (f) is connected to other positions in the molecule through two non-positional linkages that span the bicyclic ring. This means that any possible connection mode is shown in equations (f-1) to (f-10).

[0030]

[0031] For another example, as shown in equation (X'), the phenanthrene group represented by equation (X') is connected to other positions in the molecule via a non-positional linker extending from the middle of one side of the benzene ring. This means that any possible connection mode shown in equations (X'-1) to (X'-4) is included.

[0032]

[0033] In this disclosure, a non-positional substituent refers to a substituent connected by a single bond extending from the center of the ring system, indicating that the substituent can be attached to any possible position in the ring system. For example, as shown in equation (Y) below, the substituent R' represented by equation (Y) is connected to the quinoline ring by a non-positional linking bond, which means that it includes any possible connection mode shown in equations (Y-1) to (Y-7).

[0034]

[0035] In this disclosure, in a G group with M substituted or unsubstituted carbon atoms, the number of carbon atoms in the G group is M, which does not take into account the number of carbon atoms on the substituents; for example, a G group with M substituted carbon atoms has a total of M+1 carbon atoms. Correspondingly, in an aryl group or a heteroaryl group with M substituted or unsubstituted carbon atoms, the number of carbon atoms M does not take into account the number of carbon atoms on the substituents, but only considers the number of carbon atoms on the aromatic ring or heteroaryl ring. For example, It is an aryl group with 6 carbon atoms substituted by a methyl group; It is an unsubstituted aryl group with 12 carbon atoms.

[0036] In this disclosure, unless otherwise specifically defined, "hetero" means a functional group comprising at least one heteroatom such as B, N, O, S, Se, Si, or P, with the remaining atoms being carbon, hydrogen, or deuterium. An unsubstituted alkyl group may be a "saturated alkyl group" without any double or triple bonds.

[0037] In this disclosure, "alkyl" can include straight-chain alkyl or branched alkyl. An alkyl group can have 1 to 18 carbon atoms, and in this disclosure, numerical ranges such as "1 to 18" refer to integers within a given range; for example, "alkyl with 1 to 18 carbon atoms" means an alkyl group that can contain 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 carbon atoms. In some examples, the alkyl group can also be a small alkyl group having 1 to 5 carbon atoms.

[0038] Optionally, the alkyl group is selected from alkyl groups having 1 to 5 carbon atoms, including but not limited to methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, and pentyl.

[0039] In this disclosure, cycloalkyl refers to a group derived from a saturated cyclic carbon chain structure. A cycloalkyl group may have 5 to 10 carbon atoms, and in this disclosure, numerical ranges such as "cycloalkyl group having 5 to 10 carbon atoms" refer to integers within a given range; for example, "cycloalkyl group having 5 to 10 carbon atoms" means a cycloalkyl group that may contain 5 carbon atoms, 6 carbon atoms, 7 carbon atoms, 8 carbon atoms, 9 carbon atoms, or 10 carbon atoms.

[0040] Optionally, specific embodiments of cycloalkyl groups include, but are not limited to, cyclopentyl, cyclohexyl, adamantyl, norbornyl, etc.

[0041] In this disclosure, aryl refers to any optional functional group or substituent derived from an aromatic carbon ring. An aryl group can be a monocyclic aryl (e.g., phenyl) or a polycyclic aryl; in other words, an aryl group can be a monocyclic aryl, a fused-ring aryl, two or more monocyclic aryl groups conjugated by carbon-carbon bonds, a monocyclic aryl and a fused-ring aryl group conjugated by carbon-carbon bonds, or two or more fused-ring aryl groups conjugated by carbon-carbon bonds. That is, unless otherwise stated, two or more aromatic groups conjugated by carbon-carbon bonds can also be considered as aryl groups in this disclosure. Fused-ring aryl groups may include, for example, bicyclic fused aryl (e.g., naphthyl), tricyclic fused aryl (e.g., phenanthrene, fluorene, anthracene), etc. The aryl group does not contain heteroatoms such as B, N, O, S, P, Se, and Si. For example, in this disclosure, biphenyl, terphenyl, etc., are aryl groups. Examples of aryl groups may include, but are not limited to, phenyl, naphthyl, fluorenyl, anthracene, phenanthryl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, benzo[9,10]phenanthryl, pyrene, benzofluoranthracene, etc. In this disclosure, biphenyl can be understood as a phenyl-substituted aryl group or an unsubstituted aryl group. In this disclosure, the arylene group refers to a divalent group formed by the further loss of a hydrogen atom from an aryl group.

[0042] In this disclosure, the substituted aryl group may be one or more hydrogen atoms of the aryl group that are replaced by a deuterium atom, aryl, heteroaryl, alkyl, cycloalkyl, alkoxy or other group.

[0043] In this disclosure, a heteroaryl group refers to a monovalent aromatic ring or a derivative thereof containing at least one heteroatom, where the heteroatom can be at least one of B, O, N, P, Si, Se, and S. A heteroaryl group can be a monocyclic or polycyclic heteroaryl group; in other words, a heteroaryl group can be a single aromatic ring system or a system of multiple aromatic rings conjugated by carbon-carbon bonds, and any aromatic ring system can be a single aromatic monocyclic ring or a fused aromatic ring. For example, a heteroaryl group may include thiophene, furanyl, pyrroleyl, imidazolyl, thiazolyl, oxazolyl, oxadiazolyl, triazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, acridineyl, pyridazinyl, quinolinyl, quinazolinyl, quinoxolinyl, phenoxazinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, isoquinolinyl, indolyl, carbazole, benzoxazolyl, and benzimidazole. The group includes, but is not limited to, benzothiazolyl, benzocarbazolyl, benzothiophenel, dibenzothiophenel, thienozothiophenel, benzofuranyl, phenanthrolinel, isoxazolyl, thiadiazolyl, benzothiazolyl, phenothiazinyl, silanyl, dibenzofuranyl, and N-arylcarbazolyl (such as N-phenylcarbazolyl), N-heteroarylcarbazolyl (such as N-pyridylcarbazolyl), and N-alkylcarbazolyl (such as N-methylcarbazolyl), etc. Among these, thiophenel, furanyl, and phenanthrolinel are heteroaryl groups of the single aromatic ring type, while N-arylcarbazolyl (such as N-phenylcarbazolyl) and N-heteroarylcarbazolyl are heteroaryl groups of the polycyclic system type linked by carbon-carbon conjugation.

[0044] In this disclosure, the substituted heteroaryl group may be one or more hydrogen atoms of the heteroaryl group that are replaced by groups such as deuterium, aryl, heteroaryl, alkyl, cycloalkyl, alkoxy, etc.

[0045] This disclosure provides a compound having the structural formula shown in Chemical Formula 1:

[0046]

[0047] Wherein, L1 and L2 are each independently selected from single bonds or linking groups, and the linking group is selected from divalent arylene or divalent heteroarylene;

[0048] Q is an aryl group with 2 to 5 fused rings, substituted or unsubstituted; or a heteroaryl group with 2 to 5 fused rings, substituted or unsubstituted.

[0049] R1 to R3 may be the same as or different from each other, and each is independently selected from the group consisting of deuterium, fluorine, chlorine, substituted or unsubstituted alkyl with 1 to 12 carbon atoms, substituted or unsubstituted haloalkyl with 1 to 12 carbon atoms, substituted or unsubstituted alkoxy with 1 to 12 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 10 carbon atoms, substituted or unsubstituted aryl with 6 to 60 carbon atoms, and substituted or unsubstituted heteroaryl with 3 to 60 carbon atoms;

[0050] R4 is selected from deuterium, halogen groups, cyano, substituted or unsubstituted alkylamine group with 1 to 20 carbon atoms, substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group with 1 to 20 carbon atoms, substituted or unsubstituted aryloxy group with 6 to 30 carbon atoms, substituted or unsubstituted aryl group with 6 to 30 carbon atoms, and substituted or unsubstituted heterocyclic group with 5 to 30 carbon atoms.

[0051] a1 is an integer from 0 to 4; when a1 is greater than 1, any two R1s are the same or different.

[0052] a2 is an integer from 0 to 4; when a2 is greater than 1, any two R2 values ​​are the same or different.

[0053] a3 is an integer from 0 to 3; when a3 is greater than 1, any two R3s are the same or different;

[0054] a4 is an integer from 0 to 8; when a4 is greater than 1, any two R4s are the same or different.

[0055] The compounds disclosed herein are anthracene ring compounds. Anthracene rings themselves possess high fluorescence quantum yields and can achieve blue light emission; however, anthracene rings are planar structures formed by the fusion of three benzene rings. Such structures easily form π-π stacking, causing material crystallization, which in turn leads to crucible blockage during the vapor deposition process due to crystallization. The compound of chemical formula 1 of this invention introduces a tripterene group into the anthracene ring structure. The tripterene group has a three-dimensional paddle-like structure with a large space volume. The introduction of the large-space-volume tripterene group can regulate the intermolecular forces of the compound, reduce intermolecular stacking effects and molecular crystallization ability, and improve device lifespan. Furthermore, the introduction of this tripterene group can reduce the crystallization ability of the compound, thereby reducing or eliminating crucible blockage caused by crystallization during the vapor deposition process, and thus improving the mass production characteristics of the compound.

[0056] Furthermore, the introduction of large-volume triterpenoid groups reduces intermolecular interactions, preventing a redshift in the compound's spectrum under thin-film conditions. This redshift, in turn, avoids the efficiency reduction of organic light-emitting devices. For example, this compound can serve as a blue light host material. Typically, if the blue light host material experiences a redshift in its spectrum under thin-film conditions, the excitons formed on the blue light host material cannot be effectively transferred to the blue light guest material, leading to a decrease in the luminous efficiency of the blue light guest material and ultimately, a decrease in the efficiency of the organic light-emitting device.

[0057] In one embodiment of this disclosure, Q is selected from the groups shown in Chemical Formulas 3-1 to 3-13:

[0058]

[0059]

[0060] Among them, X1-X5 are each independently selected from O, S, C(R)2, N(R), and Si(R)2;

[0061] X6-X7 are each independently selected from single bond, O, S, C(R)2, N(R), Si(R)2, and X6 and X7 are not selected from single bond at the same time;

[0062] R is selected from the group consisting of hydrogen, deuterium, fluorine, chlorine, substituted or unsubstituted alkyl with 1 to 12 carbon atoms, substituted or unsubstituted haloalkyl with 1 to 12 carbon atoms, substituted or unsubstituted alkoxy with 1 to 12 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 10 carbon atoms, substituted or unsubstituted aryl with 6 to 60 carbon atoms, and substituted or unsubstituted heteroaryl with 3 to 60 carbon atoms;

[0063] R5~R 26 They may be the same as or different from each other, and are each independently selected from the group consisting of deuterium, fluorine, chlorine, substituted or unsubstituted alkyl groups having 1 to 12 carbon atoms, substituted or unsubstituted haloalkyl groups having 1 to 12 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 12 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 10 carbon atoms, substituted or unsubstituted aryl groups having 6 to 60 carbon atoms, and substituted or unsubstituted heteroaryl groups having 3 to 60 carbon atoms;

[0064] a5 is an integer from 0 to 7; when a5 is greater than 1, any two R5s are the same or different.

[0065] a6 is an integer from 0 to 3; when a6 is greater than 1, any two R6s are the same or different.

[0066] a7 is an integer from 0 to 6; when a7 is greater than 1, any two R7s are the same or different;

[0067] a8 is an integer from 0 to 4; when a8 is greater than 1, any two R8s are the same or different.

[0068] a9 is an integer from 0 to 5; when a9 is greater than 1, any two R9s are the same or different;

[0069] a 10 an integer between 0 and 3; a 10 When greater than 1, any two R 10 Same or different;

[0070] a 11 Integers from 0 to 6; a 11 When greater than 1, any two R 11 Same or different;

[0071] a 12 Integers from 0 to 4; a 12 When greater than 1, any two R 12 Same or different;

[0072] a 13 Integers from 0 to 5; a 13 When greater than 1, any two R 13 Same or different;

[0073] a 14 an integer between 0 and 3; a 14 When greater than 1, any two R 14 Same or different;

[0074] a 15 Integers from 0 to 6; a 15 When greater than 1, any two R 15 Same or different;

[0075] a 16 Integers from 0 to 4; a 16 When greater than 1, any two R 16 Same or different;

[0076] a 17 Integers from 0 to 5; a 17 When greater than 1, any two R 17 Same or different;

[0077] a 18 an integer between 0 and 3; a 18 When greater than 1, any two R 18 Same or different;

[0078] a 19 Integers from 0 to 6; a 19When greater than 1, any two R 19 Same or different;

[0079] a 20 Integers from 0 to 7; a 20 When greater than 1, any two R 20 Same or different;

[0080] a 21 Integers from 0 to 5; a 21 When greater than 1, any two R 21 Same or different;

[0081] a 22 Integers from 0 to 4; a 22 When greater than 1, any two R 22 Same or different;

[0082] a 23 Integers from 0 to 5; a 23 When greater than 1, any two R 23 Same or different;

[0083] a 24 Integers from 0 to 6; a 24 When greater than 1, any two R 24 Same or different;

[0084] a 25 Integers from 0 to 6; a 25 When greater than 1, any two R 25 Same or different;

[0085] a 26 Integers from 0 to 6; a 26 When greater than 1, any two R 26 Same or different.

[0086] The groups shown in the above chemical formulas 3-1 to 3-13 all have planar large conjugated structures. When these structures are introduced into chemical formula 1 and connected to anthracene groups, the compound can form a large conjugated structure, which is beneficial to improving the mobility of the material and thus improving the efficiency of the device.

[0087] In some examples, group Q has a dibenzoheterocyclic structure. For instance, Q is selected from groups shown in Chemical Formulas 3-1 to 3-8, and X1-X5 are each independently selected from O, S, and N(R). Group Q with a dibenzoheterocyclic structure can form a better conjugation effect with anthracene groups, which can prolong the conjugation of electron-withdrawing and electron-donating segments, resulting in a faster mobility of the compound and better electron transport, thereby improving device efficiency. Furthermore, group Q with a dibenzoheterocyclic structure contains heteroatoms (e.g., O, S, N), and the presence of heteroatoms in the molecule gives the compound greater polarity. For example, using this compound to prepare a blue light host material improves the interfacial energy level between the blue light host material and adjacent functional layers (e.g., luminescent auxiliary layers or hole-blocking layers), improves the injection characteristics of the blue light host material, further strengthens the interaction with adjacent functional layers, and reduces the operating voltage of the device.

[0088] In some embodiments, Q is selected from the group consisting of the following groups: chemical formula 3-1, chemical formula 3-2, chemical formula 3-4, chemical formula 3-6, chemical formula 3-8a, chemical formula 3-8b, chemical formula 3-9, chemical formula 3-10, chemical formula 3-11a, chemical formula 3-12a, and chemical formula 3-13.

[0089]

[0090]

[0091] Thus, by selecting the connection position between group Q and L2, group Q can have greater spatial competition with anthracene or L2, thereby further enhancing the stereochemistry of the compound shown in Formula 1 and further reducing many problems caused by the excessive planarity of the compound shown in Formula 1, such as easy crystallization and excessive intermolecular interaction forces.

[0092] In one embodiment of this disclosure, X1-X5 are each independently selected from O and S; X6-X7 are each independently selected from single bond, O, and S; and X6 and X7 have one and only one selected from single bond.

[0093] In one embodiment of this disclosure, R5~R 26 Each group is independently selected from the group consisting of deuterium, all deuterated or undeuterated methyl groups, and aryl groups; the aryl groups are selected from all deuterated or undeuterated phenyl groups, all deuterated or undeuterated biphenyl groups, all deuterated or undeuterated naphthyl groups, all deuterated or undeuterated anthracel groups, all deuterated or undeuterated phenanthryl groups, and groups formed by two or three of the above groups linked together by single bonds.

[0094] In one example, R5~R 26 Each group is independently selected from the group consisting of deuterium, all deuterated methyl groups, and aryl groups; the aryl groups are selected from all deuterated phenyl groups, all deuterated biphenyl groups, all deuterated naphthyl groups, all deuterated anthracene groups, all deuterated phenanthryl groups, and groups formed by two or three of the above groups linked together by single bonds. Thus, the electrical stability of the compound can be increased by D-replacing the Q group, improving the compound's tolerance and stability, thereby increasing the lifetime of devices containing the compound.

[0095] In one embodiment of this disclosure, L1 and L2 are each independently selected from single bonds, fully deuterated or undeuterated phenylene, fully deuterated or undeuterated biphenylene, fully deuterated or undeuterated naphthylene, fully deuterated or undeuterated anthraceneylene, fully deuterated or undeuterated phenanthrene, and groups formed by two or three of the above groups being interconnected by single bonds.

[0096] For example, L1 is selected from all deuterated phenylene, all deuterated biphenylene, all deuterated naphthylene, all deuterated anthraceneylene, all deuterated phenanthrene, and groups formed by two or three of the above groups linked together by single bonds. Thus, the electrical stability of the compound can be increased by D-replacing the L1 group, improving the compound's robustness and stability, thereby increasing the lifetime of devices containing the compound.

[0097] For example, L2 is selected from all deuterated phenylene, all deuterated biphenylene, all deuterated naphthylene, all deuterated anthraceneylene, all deuterated phenanthrene, and groups formed by two or three of the above groups linked together by single bonds. Thus, D-replacing the L2 group can increase the electrical stability of the compound, improve its robustness and stability, and thereby increase the lifetime of devices containing the compound.

[0098] In one embodiment of this disclosure, R1 to R3 are all deuterium; a1 is 0 or 4; a2 is 0 or 4; a3 is 0 or 3; a1 to a3 are all 0, or all are not 0. In other words, tripterene is completely deuterated, or tripterene is not substituted. This can reduce the difficulty of preparing the compound. When a1 is 4, a2 is 4, and a3 is 3, tripterene is completely deuterated, which can increase the electrical stability of the compound, improve the compound's tolerance and stability, thereby increasing the lifetime of devices containing the compound.

[0099] In one embodiment of this disclosure, R4 is deuterium; a4 is 0 or 8. In other words, the anthracene group is fully deuterated, or the anthracene group is not substituted. This can reduce the difficulty of preparing the compound. When a4 is 8, the anthracene group is fully deuterated, which can increase the electrical stability of the compound, improve the compound's tolerance and stability, and thus increase the lifetime of devices containing the compound.

[0100] For example, the compound can be used as a blue light host material. Generally, the T1 energy level of the host material is lower than that of the guest dopant (guest material), enabling the host material to efficiently undergo the Triplet-Triplet Fusion (TTF) effect. This means that triplet excitons on the host material do not transfer to the dopant, but instead collide efficiently with each other on the host material to generate singlet excitons. These singlet excitons then transfer energy to the guest material via energy transfer, causing the guest material to emit light, thereby improving device efficiency. The blue light host material disclosed herein undergoes D-generation of anthracene rings, which can improve device lifetime. Empirically, the TTF effect mainly occurs on the host material. However, because triplet exciton collisions generate high-energy intermediates, if the energy of these intermediates exceeds the bond dissociation energy of the material itself (generally at the location of active sites, where bonds are most easily broken), it may lead to degradation of the organic material. D-generation of the host material within a certain range increases the electrical stability of the material, improves the tolerance of the host material, increases the stability of the material, and thus increases device lifetime.

[0101] In one embodiment of this disclosure, the compound is selected from the group consisting of:

[0102]

[0103]

[0104]

[0105]

[0106]

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[0155]

[0156]

[0157]

[0158]

[0159]

[0160]

[0161]

[0162]

[0163]

[0164]

[0165]

[0166]

[0167]

[0168] This disclosure also provides an organic electroluminescent device having an anode, an organic light-emitting layer, and a cathode stacked sequentially; the organic light-emitting layer comprises the aforementioned compound.

[0169] See Figure 6 The electroluminescent device is a thin-film electroluminescent device, comprising a first electrode, a light-emitting functional layer (EFL), and a second electrode stacked sequentially. The first and second electrodes can respectively provide different charge carriers to the EFL, which recombine to form excitons and emit light. In this embodiment, the second electrode can be a transparent or semi-transparent electrode capable of emitting light, allowing the light emitted from the EFL to exit through the second electrode. In one example, the first electrode E is a reflective electrode, which can further improve the light extraction efficiency of the electroluminescent device.

[0170] In this embodiment, one of the first electrode and the second electrode is an anode (AE) and the other is a cathode (CE). The anode can inject hole carriers into the light-emitting functional layer (EFL), and the cathode can inject electron carriers into the EFL. In one example, the first electrode is the anode and the second electrode is the cathode.

[0171] See Figure 6 The electroluminescent device is an OLED (organic light-emitting diode), and the light-emitting functional layer EFL may include an organic light-emitting layer EML as the light-emitting layer, and may include one or more of the following: a hole injection layer HIL, a hole transport layer HTL, an electron blocking layer EBL, a hole blocking layer HBL, an electron transport layer ETL, and an electron injection layer EIL.

[0172] In one example, the organic light-emitting layer (EML) may include a blue light host material and a light-emitting layer guest material, wherein the light-emitting layer guest material may be a fluorescent dopant and the blue light host material may be a compound provided in the embodiments of this disclosure.

[0173] In one example, the electroluminescent device includes an anode (as a first electrode), a hole injection layer, a hole transport layer, an electron blocking layer, an organic light-emitting layer (including a host material and a guest doped material), a hole blocking layer, an electron transport layer, an electron injection layer, and a cathode, which are stacked sequentially.

[0174] Optionally, the hole injection layer can be selected from, but is not limited to, inorganic oxides, p-type dopants with strong electron-withdrawing systems, and dopants in hole transport materials, such as hexacyanohexaazatriphenylene, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-p-quinone dimethyl ether (F4TCNQ), and 1,2,3-tris[(cyano)(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane. Inorganic oxides include, but are not limited to, molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide, tantalum oxide, silver oxide, tungsten oxide, and manganese oxide. The hole injection layer can also be p-type doped in the hole transport material, with a thickness of 5–30 nm, and formed by co-evaporation.

[0175] Optionally, the hole transport layer can be an aromatic amine or carbazole material, such as NPB, TPD, BAFLP, or DFLDPBi.

[0176] Optionally, the thickness of the hole transport layer (HTL) (100–2000 nm) is between 100 and 2000 nm.

[0177] Optionally, the light-emitting auxiliary layer also has good hole transport characteristics. It can be a blue light-emitting auxiliary layer, and its material can also be an aromatic amine or carbazole material, such as CBP, PCzPA, etc.

[0178] Optionally, the thickness of the light-emitting auxiliary layer is 5–100 nm.

[0179] Optionally, the blue light guest material can be a pyrene derivative, a fluorene derivative, a perylene derivative, a styrene-based amine derivative, a metal complex, etc., such as TBPe, BDAVBi, DPAVBi, FIrpic, etc.

[0180] Optionally, the hole-blocking layer and the electron transport layer are generally aromatic heterocyclic compounds, selected from, but not limited to, any one or a combination of two or more compounds and their derivatives of benzimidazole, triazine, pyrimidine, pyridine, pyrazine, quinoxaline, quinoline, diazole, diazaphosphazenecyclopentadiene, phosphine oxide, aromatic ketones, lactams, and boranes. For example, they can be OXD-7, TAZ, p-EtTAZ, BPhen, BCP, etc.

[0181] Optionally, the thickness of the hole blocking layer can be between 5 and 100 nm.

[0182] Optionally, the thickness of the electron transport layer can be between 20 and 100 nm.

[0183] Optionally, the electron-injected layer is typically an alkali metal or a metal, such as LiF, Yb, Mg, Ca, or their compounds. Optionally, the thickness of the electron-injected layer can be between 1 and 10 nm.

[0184] Optionally, the organic electroluminescent device can be formed on a substrate. In one example, the substrate can be a transparent rigid or flexible substrate material, such as glass or polyimide.

[0185] Optionally, the anode can be a high work function electrode material, such as transparent oxide ITO or IZO; it can also be a composite electrode formed by ITO / Ag / ITO, Ag / IZO, CNT / ITO, CNT / IZO, GO / ITO, GO / IZO, etc.

[0186] This disclosure also provides a display device that includes any of the organic electroluminescent devices described in the above-described embodiments. The display device can be a smartphone screen, a smartwatch screen, or other types of display devices. Since this display device has any of the organic electroluminescent devices described in the above-described embodiments, it has the same beneficial effects, which will not be repeated here.

[0187] Synthetic route

[0188] The compounds disclosed herein can be synthesized using the following synthetic route:

[0189]

[0190]

[0191] Referring to the reaction route above, intermediate 1-1a reacts with intermediate 1-1b to generate intermediate 1-1c; intermediate 1-1c reacts with intermediate 1-1d to generate intermediate 1-1e; intermediate 1-1e is brominated to generate intermediate 1-1f; intermediate 1-1f is coupled with intermediate 1-2b to generate the target compound. Intermediate 1-2b is generated by the reaction of intermediate 1-2a with pinacol diboronate. Specific reaction conditions for each step can be found in the examples below.

[0192] Specific embodiments of synthesis

[0193] Synthesis of intermediates 1-3

[0194]

[0195] In a three-necked flask, intermediates 1-1 (25 mmol), 1-2 (25 mmol), Pd(OAc)2 (1.25 mmol), (PCy3) (2.5 mmol), and KOAc (125 mmol) were added to dioxane, refluxed, and stirred for 12 hours. After the reaction was complete, the mixture was extracted with toluene, washed with H2O, and then recrystallized from hexane to give intermediate 1-3 in 74% yield.

[0196] Synthesis of intermediates 1-5

[0197]

[0198] Under a nitrogen atmosphere, intermediates 1-3 and 1-4 in a molar ratio of 1.2:1 (60 mmol: 50 mmol), potassium carbonate (150 mmol), and Pd(PPh3)4 (5 mmol) were dissolved in a 3:1 mixture of THF and water (300 ml). After reacting at 90 °C for 12 hours, the reaction mixture was cooled to room temperature and the resulting solid was filtered. Following filtration, the solid was washed with 100 ml tetrahydrofuran, 500 ml ethyl acetate, 500 ml water, and 300 ml ethanol. The product was dried to obtain intermediate 1-5 (yield: 86.8%).

[0199] Synthesis of intermediates 1-6

[0200]

[0201] Intermediate 1-5 (46 mmol) was dissolved in THF (500 mL), and NBS (50.7 mmol) dissolved in DMF was added. The mixture was stirred at room temperature for 12 hours. After the reaction was terminated, the solid produced was filtered, washed with distilled water, and dried to obtain intermediate 1-6 (yield: 77.56%).

[0202] Synthesis of compound BH-1

[0203]

[0204] Refer to the synthesis method of intermediates 1-3, in which 1-bromo-3-phenyl-naphthalene is reacted with pinacol diboronic acid ester to generate intermediates 1-7a.

[0205] Referring to the synthesis method of intermediates 1-5, intermediates 1-6 and 1-7a were coupled to generate compound BH-1 in 80.3% yield.

[0206] The 1H NMR (400 MHz, DMSO) characterization of compound BH-1 was as follows: δ 9.01 (s, 1H), 8.23 ​​(d, J = 12.9 Hz, 5H), 8.06 (s, 1H), 7.94 (s, 1H), 7.86 (s, 1H), 7.74 (d, J = 8.1 Hz, 3H), 7.61 (s, 1H), 7.56–7.26 (m, 13H), 7.09 (s, 4H), 4.90 (d, J = 2.3 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-1 was as follows: m / z: 632.25.

[0207] Synthesis of compound BH-2

[0208]

[0209] Intermediate 1-7b was prepared using the same method as intermediate 1-7a.

[0210] Following the synthetic method of compound BH-1, intermediate 1-6 and intermediate 1-7b were coupled to generate compound BH-2 with a yield of 88.8%.

[0211] The 1H NMR (400 MHz, DMSO) characterization of compound BH-2 was as follows: δ 8.21 (s, 4H), 7.98 (s, 1H), 7.89 (s, 1H), 7.82 (s, 1H), 7.74 (s, 1H), 7.69 (s, 1H), 7.66–7.49 (m, 3H), 7.46–7.35 (m, 9H), 7.31 (s, 1H), 7.09 (s, 4H), 4.85 (d, J = 5.2 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-2 was as follows: m / z: 596.21.

[0212] Synthesis of compound BH-3

[0213]

[0214] Intermediate 1-7c was prepared according to the preparation method of intermediate 1-7a.

[0215] Following the synthetic method of compound BH-1, intermediates 1-6 and 1-7c were coupled to generate compound BH-3 with a yield of 87.2%.

[0216] The 1H NMR (400 MHz, DMSO) characterization of compound BH-3 was as follows: δ 8.35–8.04 (m, 6H), 7.91 (s, 1H), 7.86–7.50 (m, 9H), 7.40 (t, J = 4.6 Hz, 8H), 7.09 (s, 4H), 4.87 (d, J = 4.2 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-3 was as follows: m / z: 646.23.

[0217] Synthesis of compound BH-4

[0218]

[0219] Intermediate 1-7d was prepared according to the preparation method of intermediate 1-7a.

[0220] Following the synthetic method of compound BH-1, intermediates 1-6 and 1-7d were coupled to generate compound BH-4 with a yield of 84.2%.

[0221] The 1H NMR (400 MHz, DMSO) characterization of compound BH-4 was as follows: δ 8.22 (d, J = 4.0 Hz, 5H), 8.11 (s, 1H), 7.89 (s, 1H), 7.88–7.73 (m, 3H), 7.64 (dd, J = 31.0, 17.0 Hz, 5H), 7.52–7.32 (m, 9H), 7.09 (s, 4H), 4.93 (d, J = 2.8 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-4 was as follows: m / z: 646.23.

[0222] Synthesis of compound BH-5

[0223]

[0224] Intermediate 1-7e was prepared according to the preparation method of intermediate 1-7a.

[0225] Following the synthetic method of compound BH-1, intermediates 1-6 and 1-7e were coupled to generate compound BH-5 with a yield of 83.9%.

[0226] The 1H NMR (400 MHz, DMSO) characterization of compound BH-5 was as follows: δ 9.08 (s, 1H), 8.84 (s, 1H), 8.36 (s, 1H), 8.24 (d, J = 24.0 Hz, 5H), 7.88 (d, J = 14.5 Hz, 2H), 7.82–7.55 (m, 6H), 7.40 (t, J = 3.2 Hz, 8H), 7.09 (s, 4H), 4.91 (d, J = 2.4 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-5 was as follows: m / z: 606.23.

[0227] Synthesis of compound BH-6

[0228]

[0229] Intermediate 1-7f was prepared according to the preparation method of intermediate 1-7a.

[0230] Following the synthetic method of compound BH-1, intermediate 1-6 and intermediate 1-7f were coupled to generate compound BH-6 with a yield of 86.4%.

[0231] The 1H NMR (400 MHz, DMSO) characterization of compound BH-6 was as follows: δ 8.21 (s, 4H), 8.03 (s, 1H), 7.94 (s, 1H), 7.89 (s, 1H), 7.84 (s, 1H), 7.82 (s, 1H), 7.77 (s, 1H), 7.75 (d, J = 1.0 Hz, 2H), 7.62 (s, 2H), 7.53 (m, 2H), 7.40 (dd, J = 5.2, 2.8 Hz, 10H), 7.09 (s, 4H), 4.85 (d, J = 3.8 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-6 was as follows: m / z: 672.25.

[0232] Synthesis of compound BH-7

[0233]

[0234] Intermediate 1-7g was prepared according to the preparation method of intermediate 1-7a.

[0235] Following the synthetic method of compound BH-1, intermediate 1-6 and intermediate 1-7g were coupled to generate compound BH-7 with a yield of 87.67%.

[0236] The 1H NMR (400 MHz, DMSO) characterization of compound BH-7 was as follows: δ 8.32–8.10 (m, 6H), 7.98 (s, 1H), 7.92–7.67 (m, 5H), 7.67–7.50 (m, 4H), 7.49–7.23 (m, 10H), 7.09 (s, 4H), 4.83 (d, J = 3.7 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-7 was as follows: m / z: 672.25.

[0237] Following the synthetic method of compound BH-1, the following was synthesized: Figure 1 The table shown and Figure 2 The table shows compounds BH-8 to BH-17. When synthesizing compounds BH-8 to BH-12, the following methods were used: Figure 1 Intermediate 1 in the table shown replaces intermediates 1-6 in the synthesis of compound BH-1. Figure 1 Intermediate 2 in the table shown replaces intermediates 1-7a in the synthesis of compound BH-1. In the synthesis of compounds BH-13 to BH-16, the following are used: Figure 2 Intermediate 2 in the table shown replaces intermediates 1-7a in the synthesis of compound BH-1. In the synthesis of compound BH-17, intermediate 2 is used... Figure 2 Intermediate 1 in the table shown replaces intermediates 1-6 in the synthesis of compound BH-1. Figure 2 Intermediate 2 in the table shown replaces intermediates 1-7a in the synthesis of compound BH-1.

[0238] The 1H NMR and mass spectra of compounds BH-8 to BH-17 obtained during preparation are as follows:

[0239] The 1H NMR (400 MHz, DMSO) characterization of compound BH-8 was as follows: δ 9.01 (s, 1H), 8.24 (s, 1H), 8.06 (s, 1H), 7.94 (s, 1H), 7.86 (s, 1H), 7.74 (d, J = 8.1 Hz, 3H), 7.61 (s, 1H), 7.55–7.27 (m, 9H), 7.09 (s, 4H), 4.90 (d, J = 2.2 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-8 was m / z: 640.30.

[0240] The 1H NMR (400 MHz, DMSO) characterization of compound BH-9 was as follows: δ 9.01 (s, 1H), 8.24 (s, 1H), 8.06 (s, 1H), 7.94 (s, 1H), 7.86 (s, 1H), 7.73 (s, 1H), 7.61 (s, 1H), 7.53–7.28 (m, 6H), 7.09 (s, 4H), 4.90 (d, J = 2.0 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-9 was m / z: 645.33.

[0241] The 1H NMR (400 MHz, DMSO) characterization of compound BH-10 was as follows: δ 8.25 (s, 1H), 7.98 (s, 1H), 7.93–7.67 (m, 4H), 7.58 (d, J = 28.3 Hz, 2H), 7.48–7.22 (m, 6H), 7.09 (s, 4H), 4.83 (d, J = 5.5 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-10 was m / z: 684.32.

[0242] The 1H NMR (400 MHz, DMSO) characterization of compound BH-11 was as follows: δ 7.85 (s, 1H), 7.73 (s, 1H), 7.61 (s, 1H), 7.40 (d, J = 4.2 Hz, 4H), 7.09 (s, 4H), 4.83 (d, J = 4.2 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-11 was as follows: m / z: 611.31.

[0243] The 1H NMR (400 MHz, DMSO) characterization of compound BH-12 was as follows: δ 7.85 (s, 1H), 7.73 (s, 1H), 7.62 (s, 1H), 7.40 (d, J = 3.8 Hz, 4H), 7.09 (s, 4H), 4.83 (d, J = 3.4 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-12 was as follows: m / z: 663.34.

[0244] The 1H NMR (400 MHz, DMSO) characterization of compound BH-13 was as follows: δ 9.01 (s, 1H), 8.23 ​​(d, J = 12.9 Hz, 5H), 8.06 (s, 1H), 7.94 (s, 1H), 7.86 (s, 1H), 7.73 (s, 1H), 7.61 (s, 1H), 7.53–7.27 (m, 10H), 7.09 (s, 4H), 4.90 (d, J = 2.2 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-13 was m / z: 637.28.

[0245] The 1H NMR (400 MHz, DMSO) characterization of compound BH-14 was as follows: δ 8.23 ​​(d, J = 15.1 Hz, 5H), 7.98 (s, 1H), 7.93–7.68 (m, 4H), 7.58 (d, J = 28.3 Hz, 2H), 7.47–7.23 (m, 10H), 7.09 (s, 4H), 4.83 (d, J = 5.5 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-14 was m / z: 676.27.

[0246] The 1H NMR (400 MHz, DMSO) characterization of compound BH-15 was as follows: δ 8.21 (s, 4H), 7.85 (s, 1H), 7.73 (s, 1H), 7.61 (s, 1H), 7.49–7.28 (m, 8H), 7.09 (s, 4H), 4.83 (d, J = 4.2 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-15 was as follows: m / z: 603.26.

[0247] The 1H NMR (400 MHz, DMSO) characterization of compound BH-16 was as follows: δ 8.21 (s, 4H), 7.91 (s, 1H), 7.78 (s, 1H), 7.64 (s, 1H), 7.40 (t, J = 4.6 Hz, 8H), 7.09 (s, 4H), 4.87 (d, J = 4.2 Hz, 2H). The mass spectrometry (MS) characterization of compound BH-16 was m / z: 655.29.

[0248] The compound BH-17 was characterized by 1H NMR (400 MHz, DMSO) as δ 4.85 (d, J = 0.5 Hz, 2H). The compound BH-17 was characterized by mass spectrometry (MS) as m / z 674.41.

[0249] Physical property characterization:

[0250] The electron cloud distribution of the compound was simulated using molecular simulation software; the results are shown in [link to results]. Figure 3 The simulation results above show that the electron clouds of the compounds of this invention in the HOMO (highest occupied molecular orbital), LUMO (lowest unoccupied molecular orbital), S1 (first excited singlet state), and T1 (first excited triplet state) are all distributed on anthracene. Blue light host materials require a wide band gap, and anthracene just meets the requirement of a wide band gap (the energy difference between the HOMO and LUMO energy levels is relatively large). Such material characteristics can better match blue light emission.

[0251] The compounds provided in this disclosure are used as the blue light host material, and the electron clouds of the T1 energy level of the blue light host material are all distributed on anthracene. Because anthracene has a fused structure and good conjugation, the blue light host material has a low T1 energy level. Thus, when using the compounds provided in this disclosure as the blue light host material, more material choices are available for adjacent functional layers (the T1 energy level of the functional layer material only needs to be higher than that of the blue light host material), thereby effectively confining excitons in the emitting layer, greatly improving exciton utilization efficiency, and thus significantly improving the luminous efficiency of the device. Furthermore, when using the compounds provided in this invention as the blue light host material, selecting a blue light guest material with a T1 energy level higher than that of the blue light host material allows for better TTF (Total Tilting-Fold Effect) on the emitting host material, thereby improving the device efficiency.

[0252] This disclosure also determined some performance parameters of certain compounds. The HOMO / LUMO energy levels were measured using AC3, CV, and UV spectroscopy; the mobilities (HOD: ITO / P-HTL (4%) 10 nm / BH 200 nm / Ag 80 nm; EOD: ITO / HBL 10 nm / BH 150 nm / ETL:Liq (5:5) 5 nm / Mg:Ag (8:2) 80 nm) were measured using SCLC; and the recombination energy was obtained through simulation calculations. The test results are shown below. Figure 4 and Figure 5 Among them, HOD is a device with only a hole transport region, EOD is a device with only an electron transport region, BH is the blue light host material to be tested, and P-HTL is a composite material of HAT-CN and NPB. The material structures used are as follows:

[0253]

[0254]

[0255] See Figure 4 and Figure 5 The results show that, compared with the comparative compounds, the compounds of this invention possess the group shown in Formula 1, but the HOMO / LUMO energy levels do not change significantly. This is because the electron clouds of HOMO and LUMO are mainly distributed on the anthracene ring. All tested compounds possess a tripterene group. The carbon skeleton structure of the tripterene group is very stable, so the molecular structure containing tripterene has a relatively stable geometric configuration, making the molecule less prone to deformation under an applied electric field and resulting in a lower recombination energy. Compared with the comparative compounds, the compounds provided by this invention have higher electron mobility.

[0256] In addition, the introduction of large-volume triterpenoid stereogroups into these blue light host materials can reduce intermolecular interactions and prevent the host material from experiencing a redshift in its spectrum under thin-film conditions. This would prevent the excitons formed on the host material from being effectively transferred to the guest material, thus reducing the luminous efficiency of the guest material and consequently the efficiency of the device.

[0257] Furthermore, these blue light-emitting host materials incorporate dibenzo[a] structures (containing heteroatoms) into their molecules. Dibenzo[a] structures exhibit good conjugation effects; when directly connected to anthracene, they increase conjugation, resulting in deeper and faster electron mobility and improved electron transport, thus enhancing device efficiency. Simultaneously, the presence of heteroatoms (O, S, N) imparts greater polarity, improving the interfacial energy levels between the material and adjacent functional layers, enhancing injection characteristics, further strengthening interactions with adjacent functional layers, and reducing device operating voltage.

[0258] Glass transition temperature Tg

[0259] The glass transition temperature (Tg) determines the thermal stability of a material during vapor deposition; the higher the Tg, the better the thermal stability of the material.

[0260] The measuring instrument was a DSC differential scanning calorimeter; the test atmosphere was nitrogen, the heating rate was 10℃ / min, and the temperature range was 50–380℃; the measurement results of the glass transition temperature (Tg) of each compound are shown in Table 1:

[0261] Table 1

[0262] Compound Tg (°C) Compound BH-1 130 Compound BH-2 147 Compound BH-3 142 Compound BH-4 151 Compound BH-5 135 Compound BH-6 129 Compound BH-7 132 Compound BH-8 130 Compound BH-9 129 Compound BH-10 137 Compound BH-11 139 Compound BH-12 143 Compound BH-13 132 Compound BH-14 136 Compound BH-15 145 Compound BH-16 142 Compound BH-17 145 Comparative Compound 124

[0263] In the blue light host material of this embodiment, the triterpenoid groups have a rigid three-dimensional structure. This rigid structure is beneficial for increasing the material's thermodynamic stability (Tg). A high Tg is beneficial for improving the material's thermodynamic stability, making it less prone to decomposition during vapor deposition and exhibiting good film-forming properties. These are fundamental conditions that enable the material to undergo vapor deposition and maintain a high lifespan. This results in better physical and thermal stability, excellent durability and heat resistance, thereby significantly improving the lifespan of organic electroluminescent devices.

[0264] Device fabrication and testing

[0265] An organic light-emitting device (OLED) with the following structure was fabricated: The anode was ITO with a thickness of 10 nm; the hole injection layer was HAT-CN with a thickness of 10 nm; the hole transport layer was NPB with a thickness of 100 nm; the electron blocking layer was mCBP with a thickness of 35 nm; the emitting layer was a mixture of a blue light host material and BD (3 wt%) with a thickness of 20 nm; the blue light host material used varied in different embodiments; the hole blocking layer was HB with a thickness of 5 nm; the electron transport layer was a mixture of ET and LiQ (1:1) with a thickness of 30 nm; the electron injection layer was Yb with a thickness of 1 nm; and the cathode was Mg / Ag (1:9) with a thickness of 100 nm. The blue light host materials corresponding to different embodiments are shown in Table 2.

[0266] The fabrication process of the organic electroluminescent device described in the device embodiments of the present invention is as follows:

[0267] (1) The glass plate with ITO was ultrasonically treated in a cleaning agent, rinsed in deionized water, ultrasonically degreased in an acetone-ethanol mixed solvent, and baked in a clean environment until all moisture was removed.

[0268] (2) Place the glass substrate with the anode in the vacuum chamber and evacuate it to 1×10-5 to 1×10-6 Pa. Vacuum vapor deposit hole injection material is deposited on the anode layer film to form hole injection material.

[0269] (3) Hole transport material is vapor-deposited on the hole injection layer to form a hole transport layer.

[0270] (4) Vacuum evaporation deposition of an electron blocking layer for the hole transport device on top of the hole transport layer;

[0271] (5) A light-emitting layer of the device is vacuum-deposited on top of an electron blocking layer. The light-emitting layer includes a blue light host material and a guest material, using a multi-source co-evaporation method.

[0272] (6) A hole blocking layer of the device is vacuum-deposited on top of the light-emitting layer;

[0273] (7) Electron transport layer of a vacuum-deposited device above a hole blocking layer;

[0274] (8) Yb is vacuum-deposited on the electron transport layer (ETL) as an electron injection layer.

[0275] (9) A Mg / Ag (1:9) layer is deposited on the electron injection layer as the cathode of the device.

[0276] The materials used in the above preparation process are as follows:

[0277]

[0278] Referring to Table 2, the blue light host material in the organic electroluminescent device prepared in Example 1 is compound BH-1; the blue light host material in the organic electroluminescent device prepared in Example 2 is compound BH-2; similarly, the blue light host material in the organic electroluminescent device prepared in Example 17 is compound BH-17; and the blue light host material in the organic electroluminescent device prepared in the comparative examples is the comparative compound (ADN).

[0279] The organic electroluminescent device prepared in the above embodiments was subjected to a fixed current density of 15 mA / cm². 2 The driving voltage and luminous efficiency were measured, and the test results are shown in Table 2.

[0280] Table 2

[0281] Example Blue host material Voltage Emission peak (nm) Efficiency Lifetime Example 1 Compound BH-1 99％ 460 108％ 119％ Example 2 Compound BH-2 95％ 460 122％ 116％ Example 3 Compound BH-3 94％ 459 126％ 113％ Example 4 Compound BH-4 95％ 461 123％ 106％ Example 5 Compound BH-5 99％ 460 123％ 108％ Example 6 Compound BH-6 96％ 459 127％ 116％ Example 7 Compound BH-7 98％ 460 125％ 132％ Example 8 Compound BH-8 100％ 461 126％ 129％ Example 9 Compound BH-9 98％ 461 128％ 135％ Example 10 Compound BH-10 97％ 461 127％ 123％ Example 11 Compound BH-11 96％ 462 128％ 117％ Example 12 Compound BH-12 94％ 461 131％ 122％ Example 13 Compound BH-13 94％ 459 116％ 130％ Example 14 Compound BH-14 98％ 460 122％ 128％ Example 15 Compound BH-15 94％ 461 128％ 115％ Example 16 Compound BH-16 94％ 459 124％ 118％ Example 17 Compound BH-17 93％ 458 132％ 125％ Comparative Example Comparative Compound 100％ 460 100％ 100％

[0282] In Table 2, all test data are normalized test data, with the test results of the comparative examples set to 100%.

[0283] Referring to Table 2, although the comparative compounds also possess anthracene groups, when the organic layer host material of the organic electroluminescent device is replaced with the compound provided in this disclosure as the blue light host material, the driving voltage of the organic electroluminescent device decreases, the efficiency increases, and the lifetime decreases. This indicates that the compound provided in this disclosure, by introducing tripterene and Q groups, can improve the lifetime and efficiency of the organic electroluminescent device and facilitate the reduction of the driving voltage of the organic electroluminescent device.

Claims

1. A compound, characterized in that, Its structural formula is shown in chemical formula 1: Wherein, L1 and L2 are each independently selected from single bonds or linking groups, and the linking group is selected from divalent arylene or divalent heteroarylene; Q is an aryl group with 2 to 5 fused rings, substituted or unsubstituted; or a heteroaryl group with 2 to 5 fused rings, substituted or unsubstituted. R1 to R3 may be the same as or different from each other, and each is independently selected from the group consisting of deuterium, fluorine, chlorine, substituted or unsubstituted alkyl with 1 to 12 carbon atoms, substituted or unsubstituted haloalkyl with 1 to 12 carbon atoms, substituted or unsubstituted alkoxy with 1 to 12 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 10 carbon atoms, substituted or unsubstituted aryl with 6 to 60 carbon atoms, and substituted or unsubstituted heteroaryl with 3 to 60 carbon atoms; R4 is selected from deuterium, halogen groups, cyano, substituted or unsubstituted alkylamine group with 1 to 20 carbon atoms, substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group with 1 to 20 carbon atoms, substituted or unsubstituted aryloxy group with 6 to 30 carbon atoms, substituted or unsubstituted aryl group with 6 to 30 carbon atoms, and substituted or unsubstituted heterocyclic group with 5 to 30 carbon atoms. a1 is an integer from 0 to 4; when a1 is greater than 1, any two R1s are the same or different. a2 is an integer from 0 to 4; when a2 is greater than 1, any two R2 values ​​are the same or different. a3 is an integer from 0 to 3; when a3 is greater than 1, any two R3s are the same or different; a4 is an integer from 0 to 8; when a4 is greater than 1, any two R4s are the same or different.

2. The compound according to claim 1, characterized in that, Q is selected from the groups shown in chemical formulas 3-1 to 3-13 below: Among them, X1-X5 are each independently selected from O, S, C(R)2, N(R), and Si(R)2; X6-X7 are each independently selected from single bond, O, S, C(R)2, N(R), Si(R)2, and X6 and X7 are not selected from single bond at the same time; R is selected from the group consisting of hydrogen, deuterium, fluorine, chlorine, substituted or unsubstituted alkyl with 1 to 12 carbon atoms, substituted or unsubstituted haloalkyl with 1 to 12 carbon atoms, substituted or unsubstituted alkoxy with 1 to 12 carbon atoms, substituted or unsubstituted cycloalkyl with 3 to 10 carbon atoms, substituted or unsubstituted aryl with 6 to 60 carbon atoms, and substituted or unsubstituted heteroaryl with 3 to 60 carbon atoms; R5~R 26 They may be the same as or different from each other, and are each independently selected from the group consisting of deuterium, fluorine, chlorine, substituted or unsubstituted alkyl groups having 1 to 12 carbon atoms, substituted or unsubstituted haloalkyl groups having 1 to 12 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 12 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 10 carbon atoms, substituted or unsubstituted aryl groups having 6 to 60 carbon atoms, and substituted or unsubstituted heteroaryl groups having 3 to 60 carbon atoms; a5 is an integer from 0 to 7; when a5 is greater than 1, any two R5s are the same or different. a6 is an integer from 0 to 3; when a6 is greater than 1, any two R6s are the same or different. a7 is an integer from 0 to 6; when a7 is greater than 1, any two R7s are the same or different; a8 is an integer from 0 to 4; when a8 is greater than 1, any two R8s are the same or different. a9 is an integer from 0 to 5; when a9 is greater than 1, any two R9s are the same or different; a 10 an integer between 0 and 3; a 10 When greater than 1, any two R 10 Same or different; a 11 Integers from 0 to 6; a 11 When greater than 1, any two R 11 Same or different; a 12 Integers from 0 to 4; a 12 When greater than 1, any two R 12 Same or different; a 13 Integers from 0 to 5; a 13 When greater than 1, any two R 13 Same or different; a 14 an integer between 0 and 3; a 14 When greater than 1, any two R 14 Same or different; a 15 Integers from 0 to 6; a 15 When greater than 1, any two R 15 Same or different; a 16 Integers from 0 to 4; a 16 When greater than 1, any two R 16 Same or different; a 17 Integers from 0 to 5; a 17 When greater than 1, any two R 17 Same or different; a 18 an integer between 0 and 3; a 18 When greater than 1, any two R 18 Same or different; a 19 Integers from 0 to 6; a 19 When greater than 1, any two R 19 Same or different; a 20 Integers from 0 to 7; a 20 When greater than 1, any two R 20 Same or different; a 21 Integers from 0 to 5; a 21 When greater than 1, any two R 21 Same or different; a 22 Integers from 0 to 4; a 22 When greater than 1, any two R 22 Same or different; a 23 Integers from 0 to 5; a 23 When greater than 1, any two R 23 Same or different; a 24 Integers from 0 to 6; a 24 When greater than 1, any two R 24 Same or different; a 25 Integers from 0 to 6; a 25 When greater than 1, any two R 25 Same or different; a 26 Integers from 0 to 6; a 26 When greater than 1, any two R 26 Same or different.

3. The compound according to claim 2, characterized in that, Q is selected from the group consisting of the following chemical formulas: 3-1, 3-2, 3-4, 3-6, 3-8a, 3-8b, 3-9, 3-10, 3-11a, 3-12a, and 3-13.

4. The compound according to claim 2 or 3, characterized in that, X1-X5 are each independently selected from O and S; X6-X7 are each independently selected from single bond, O, and S; X6 and X7 have exactly one selected from single bond.

5. The compound according to claim 2 or 3, characterized in that, R5~R 26 Each group is independently selected from deuterium, fully deuterated or undeuterated methyl and aryl groups; The aryl group is selected from all deuterated or undeuterated phenyl groups, all deuterated or undeuterated biphenyl groups, all deuterated or undeuterated naphthyl groups, all deuterated or undeuterated anthracel groups, all deuterated or undeuterated phenanthryl groups, and groups formed by two or three of the above groups linked together by single bonds.

6. The compound according to claim 1, characterized in that, L1 and L2 are each independently selected from single bonds, fully deuterated or undeuterated phenylene, fully deuterated or undeuterated biphenylene, fully deuterated or undeuterated naphthylene, fully deuterated or undeuterated anthraceneylene, fully deuterated or undeuterated phenanthrene, and groups formed by two or three of the above groups linked together by single bonds.

7. The compound according to claim 1, characterized in that, R1 to R4 are all deuterium; a1 is 0 or 4; a2 is 0 or 4; a3 is 0 or 3; a4 is 0 or 8; a1 to a3 are all 0, or all of them are not 0.

8. The compound according to claim 1, characterized in that, Selected from the group consisting of the following compounds:

9. An organic electroluminescent device, characterized in that, It has an anode, an organic light-emitting layer and a cathode arranged in sequence; the organic light-emitting layer comprises the compound according to any one of claims 1 to 8.

10. A display device, characterized in that, Including the organic electroluminescent device as described in claim 9.

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