Organic light-emitting compound, organic electroluminescent device, display screen and electronic device

Abstract

Embodiments of the present application provide an organic light-emitting compound, an organic electroluminescent device, a display screen and an electronic device. The chemical structure of the organic light-emitting compound is shown in general formula (1). The organic light-emitting compound takes double fluorene as a skeleton, and connects main functional groups at different positions of the double fluorene, which is conducive to obtaining excellent light-emitting performance, so that the organic light-emitting compound can be efficiently applied to an organic electroluminescent device, improve the stability and efficiency of the device, and reduce the driving voltage of the device.

Description

Technical Field

[0001] This application relates to the field of organic light-emitting materials, and more particularly to an organic light-emitting compound, an organic electroluminescent device, a display screen, and an electronic device. Background Technology

[0002] Organic light-emitting diode (OLED) displays have become the mainstream in the display field due to their advantages such as thinness, light weight, wide viewing angle, active light emission, and continuously adjustable emission color. In OLED displays, organic light-emitting materials play a crucial role in their performance.

[0003] Thermally activated delayed fluorescence (TEF) materials can theoretically achieve 100% exciton utilization because they can cross the reverse gap between triplet and singlet excitons. Furthermore, they do not require coordination with heavy metal ions in their molecular structure and have lower costs. They have now become the third generation of organic light-emitting materials after traditional fluorescent and phosphorescent materials.

[0004] However, in current practical applications, TADF materials suffer from problems such as luminous efficiency roll-off and short lifetime in devices, and high-efficiency TADF materials are still relatively scarce. Summary of the Invention

[0005] This application provides an organic light-emitting compound, an organic electroluminescent device, a display screen, and an electronic device. The purpose is to provide an organic light-emitting compound with superior light-emitting performance, which can be efficiently applied to organic electroluminescent devices to improve the efficiency of organic electroluminescent devices.

[0006] In a first aspect, an organic light-emitting compound is provided, the chemical structure of which is shown in general formula (1): General formula (1), Among them, Y1 and Y2 are independently selected from any one of single bond, C(R1)2, NR1, O, S, S(=O)2, P(=O)R1, Si(R1)2 or Ge(R1)2; Each Z is independently selected from CR1 or N; Each R1 is independently selected from hydrogen atom, deuterium atom, fluorine atom, chlorine atom, bromine atom, iodine atom, cyano group, N(=O)2, N(R2)2, OR2, SR2, C(=O)R2, P(=O)R2, Si(R2)3, and C1-C atoms substituted with one or more deuterium atoms. 20 Alkyl groups, C2-C atoms substituted with one or more deuterium atoms20 Alkenyl group, C2-C substituted with one or more deuterium atoms 20 Alkyne group, C6-C substituted with one or more deuterium atoms 40 aryl, or C5-C substituted with one or more deuterium atoms. 40 Any of the heteroaryl groups; or, two R1 rings linked together to form a C6-C 18 Aromatic rings or C5-C 18 heterocyclic aromatic rings, the C6-C 18 Aromatic rings or C5-C 18 The heterocyclic aromatic ring is optionally surrounded by one or more C6-C 30 Aryl or C5-C 30 heteroaryl substitution; Each R2 is independently selected from hydrogen, deuterium, fluorine, cyano, or C1-C atoms substituted with one or more deuterium atoms. 20 Alkyl groups, C6-C atoms substituted with one or more deuterium atoms 30 aryl, or C5-C substituted with one or more deuterium atoms. 30 Any one of the heteroaryl groups; R3, R4 and R6 are each independently selected from any one of the following groups: hydrogen atom, deuterium atom, halogen group, cyano, nitro, hydroxyl, carbonyl, ester group, imide group, amide group, substituted or unsubstituted phosphine oxide group, substituted or unsubstituted alkyl group, substituted or unsubstituted cycloalkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted alkylthio group, substituted or unsubstituted arylthio group, substituted or unsubstituted alkylsulfonyl group, substituted or unsubstituted arylsulfonyl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted silyl group, substituted or unsubstituted boron group, substituted or unsubstituted amino group, substituted or unsubstituted arylphosphine group, substituted or unsubstituted aryl group, substituted or unsubstituted heteroaryl group, or substituted or unsubstituted heterocyclic group. G is selected from single bond, substituted or unsubstituted C6-C. 30 aryl, or substituted or unsubstituted C4-C 30 Any of the heteroaryl groups; A includes electron-accepting groups.

[0007] It should be noted that A including an electron-accepting group can be understood as A being an electron-accepting group, or it can be understood as A including an electron-donating group in addition to an electron-accepting group, and the electron-accepting group and the electron-donating group can be conjugated.

[0008] In the embodiments of this application, the organic light-emitting compound uses bisfluorene as a backbone and connects the main functional units at different positions of bisfluorene, which is beneficial to obtain superior light-emitting performance. This enables it to be efficiently applied to organic electroluminescent devices, improve the stability and efficiency of the devices, reduce the driving voltage of the devices, and achieve high durability.

[0009] First, the organic light-emitting compounds provided in this application achieve space charge transfer between electron-donating and electron-accepting groups by attaching electron-accepting and electron-donating groups at different positions of the bisfluorene. For example, an electron-accepting group A is attached to position 11 of the bisfluorene, and an electron-donating group is attached to at least one of positions 10 or 12 of the bisfluorene, to form a DA-type or DAD-type organic light-emitting compound with space charge transfer.

[0010] First, the electron-donating and electron-accepting groups involved in space charge transfer are connected by a non-conjugated structure, resulting in minimal overlap of electron clouds and thus a smaller Δ. E ST This facilitates the fulfillment of the reverse gap crossing conditions between triplet and singlet excitons, enabling organic light-emitting compounds to exhibit TADF characteristics and achieve 100% exciton utilization. Consequently, organic light-emitting compounds with superior optical performance and high luminous efficiency can be obtained.

[0011] Second, the complete separation of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LOMO) in organic light-emitting compounds based on space charge transfer is beneficial to improving the conversion efficiency from triplet excitons to singlet excitons and thus to obtaining highly efficient organic light-emitting compounds.

[0012] Third, compared to electron donors and electron acceptors connected by a conjugate bridge, organic light-emitting compounds based on space charge transfer have shorter emission wavelengths, which is advantageous for achieving blue light.

[0013] Fourth, since the electron clouds of electron-donating and electron-accepting groups can interact spatially, organic light-emitting compounds have a high fluorescence quantum yield, which in turn can achieve high device efficiency.

[0014] Secondly, according to the organic light-emitting compound provided in the embodiments of this application, by connecting the light-emitting center of the organic light-emitting compound to a fixed position of bisfluorene, and the substituent connected at the adjacent position of the fixed position as a steric hindrance group, it is possible to limit and block the light-emitting center, which is beneficial to prevent molecular accumulation, reduce the phosphor aggregation quenching effect, obtain a device with a narrow emission spectrum and high color purity, and improve the stability and efficiency of the device.

[0015] For example, in the embodiments of this application, A includes a conjugated electron-donating group and an electron-accepting group, which can be connected at the 11 position of the bisfluorene as the luminescent center of the organic luminescent compound. The substituents connected at the 10 and / or 12 positions of the bisfluorene can serve as steric hindrance groups of A, which helps to prevent intermolecular stacking.

[0016] Finally, the organic light-emitting compounds provided in this application use bisfluorene as a rigid framework, which helps to suppress large-amplitude molecular bond vibrations in the excited state, improve the problem of device efficiency roll-off, and enhance the device's lifetime and stability.

[0017] In conjunction with the first aspect, in certain implementations of the first aspect, A is selected from any one of cyano, sulfone, carbonyl, ester, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted alkenyl, substituted or unsubstituted aralkyl, substituted or unsubstituted areneyl, substituted or unsubstituted aramine, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic.

[0018] According to the organic light-emitting compound provided in the embodiments of this application, A may include any of the above-mentioned electron-accepting groups, thereby facilitating charge transfer between the compound and the electron-donating groups to achieve the purpose of light emission.

[0019] In conjunction with the first aspect, in certain implementations of the first aspect, the A is selected from any of the following groups:

[0020] In this context, R5 at each point is independently selected from hydrogen atoms, cyano groups, and substituted or unsubstituted C1-C atoms. 10 Alkyl, substituted or unsubstituted C6-C 24 Aromatic amino groups, substituted or unsubstituted C6-C 24 It is any one of aryl, substituted or unsubstituted aromatic heterol, substituted or unsubstituted pyridine, or substituted or unsubstituted thiophene.

[0021] According to the organic light-emitting compound provided in the embodiments of this application, A may include any of the electron-accepting groups mentioned above, thereby facilitating space charge transfer between the electron-donating groups and the organic light-emitting compound, enabling the organic light-emitting compound to have TADF characteristics and achieve 100% exciton utilization, thereby obtaining an organic light-emitting compound with superior optical performance and high luminous efficiency.

[0022] In conjunction with the first aspect, in some implementations of the first aspect, at least one of Y1 and Y2 is selected from any one of NR1, O, S, S(=O)2 or P(=O)R1.

[0023] According to the organic light-emitting compounds provided in the embodiments of this application, at least one of Y1 and Y2 may include any of the aforementioned electron-donating groups, thereby allowing at least one electron-donating group to be attached to the 10 or 12 position of the bisfluorene, forming a DA-type or DAD-type organic light-emitting compound with an electron-accepting group attached to the 11 position of the bisfluorene. Furthermore, compared to DA-type organic light-emitting compounds, DAD-type organic light-emitting compounds can have higher efficiency due to the additional electron-donating group on one side.

[0024] In conjunction with the first aspect, in certain implementations of the first aspect, the chemical structure of the organic light-emitting compound is as shown in Formula I. a ~I d As shown in any of the following:

[0025] I a I b I c

[0026] I d .

[0027] The organic light-emitting compounds provided in the embodiments of this application are selected from the above formula I. a ~I d The chemical structure shown allows for space charge transfer between the electron-accepting group at the 11-position of bisfluorene and the electron-donating groups at the 10- and 12-positions of bisfluorene, giving the organic light-emitting compound TADF characteristics and enabling 100% exciton utilization. This results in organic light-emitting compounds with superior optical performance and high luminous efficiency.

[0028] In conjunction with the first aspect, in some implementations of the first aspect, A further comprises an electron-donating group, wherein the electron-accepting group and the electron-donating group are conjugately connected. The A group is selected from any of the following groups:

[0029] In this context, the R5 at each point is independently selected from hydrogen atoms, cyano groups, and substituted or unsubstituted C1-C atoms. 10 Alkyl, C6-C 24 Aromatic amino groups, substituted or unsubstituted C6-C 24It is any one of aryl, substituted or unsubstituted aromatic heterol, substituted or unsubstituted pyridine, or substituted or unsubstituted thiophene.

[0030] According to the organic light-emitting compound provided in the embodiments of this application, A can be selected from any of the groups that include electron-accepting groups and electron-donating groups, and the electron-accepting groups and electron-donating groups are conjugated together. Thus, A can be directly used as the light-emitting center of the organic light-emitting compound to achieve light emission.

[0031] In conjunction with the first aspect, in some implementations of the first aspect, at least one of Y1 and Y2 is selected from a single bond, C(R1)2, Si(R1)2 or Ge(R1)2.

[0032] According to the organic light-emitting compound provided in the embodiments of this application, at least one of Y1 and Y2 is selected from any of the above-mentioned groups. This is beneficial for the substituent group connected at the 10 and / or 12 positions of the bisfluorene to serve as a steric hindrance group for the light-emitting center A, so as to avoid intermolecular stacking, reduce the phosphor aggregation quenching effect, obtain a device with a narrow emission spectrum and high color purity, and improve the stability and efficiency of the device.

[0033] In conjunction with the first aspect, in certain implementations of the first aspect, the chemical structure of the organic light-emitting compound is as shown in Formula I. e ~I h As shown in any of the following:

[0034] I e I f I g

[0035] I h .

[0036] The organic light-emitting compounds provided in the embodiments of this application are selected from the above formula I. e ~I h The chemical structure shown shows that the substituents attached to the 10 and 12 positions of the bisfluorene can serve as steric hindrance groups attached to the luminescent center at the 11 position of the bisfluorene. This helps to prevent molecular accumulation, reduce the phosphor aggregation quenching effect, obtain devices with narrow emission spectra and high color purity, and improve the stability and efficiency of the devices.

[0037] In conjunction with the first aspect, in certain implementations of the first aspect, the G is selected from a single bond or any of the following groups:

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055] In this context, R5 at each point is independently selected from hydrogen atoms, cyano groups, and substituted or unsubstituted C1-C atoms. 10 Alkyl, substituted or unsubstituted C6-C 24 Aromatic amino group, substituted or unsubstituted C6-C 24 Aryl, substituted or unsubstituted C4-C 24 Any one of heteroaryl, substituted or unsubstituted pyridine, or substituted or unsubstituted thiophene.

[0056] In a second aspect, there is a use of the organic light-emitting compound comprising any one of the first aspects above, wherein the organic light-emitting compound is used to prepare an organic electroluminescent device or as a dopant in the organic electroluminescent device.

[0057] Thirdly, an organic electroluminescent device is provided, the organic electroluminescent device comprising: The first and second electrodes are set relative to each other, and An organic layer located between the first electrode and the second electrode; The organic layer includes a light-emitting layer, which includes an organic light-emitting compound as described in any one of the first aspects above.

[0058] In conjunction with the third aspect, in some implementations of the third aspect, the light-emitting layer includes a light-emitting material, a sensitizing material, and a host material, wherein at least one of the sensitizing material and the light-emitting material includes an organic light-emitting compound as described in any one of the first aspects above.

[0059] In conjunction with the third aspect, in some implementations of the third aspect, the organic layer further includes at least one of a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, and an electron injection layer stacked sequentially, with the light-emitting layer located between the electron blocking layer and the hole blocking layer. At least one of the hole injection layer, the hole transport layer, the electron blocking layer, the hole blocking layer, and the electron transport layer comprises an organic light-emitting compound as described in any one of the first aspects above.

[0060] Fourthly, a display screen is provided, including a cover plate, a back plate, and an organic electroluminescent device as described in any one of the third aspects above, the organic electroluminescent device being located between the back plate and the cover plate.

[0061] Fifthly, an electronic device is provided, including a housing assembly and a display screen as described in the fourth aspect above, the display screen being located inside the housing assembly.

[0062] The beneficial effects of the second to fifth aspects mentioned above can be found in the beneficial effects of the first aspect mentioned above, and will not be repeated here. Attached Figure Description

[0063] Figure 1 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0064] Figure 2 This is a schematic diagram of the structure of a display screen provided in an embodiment of this application.

[0065] Figure 3 This is a schematic diagram of the structure of an organic electroluminescent device provided in an embodiment of this application.

[0066] Figure 4 This is a schematic diagram of the structure of an organic electroluminescent device provided in an embodiment of this application. Detailed Implementation

[0067] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0068] The terminology used in the following embodiments is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. As used in the specification and appended claims of this application, the singular expressions “a,” “an,” “the,” “the,” “the,” and “this” are intended to also include expressions such as “one or more,” unless the context clearly indicates otherwise. It should also be understood that the term “and / or” is used to describe the relationship between related objects, indicating that three relationships may exist; for example, A and / or B can indicate: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character “ / ” generally indicates that the preceding and following related objects are in an “or” relationship.

[0069] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0070] To facilitate a better understanding of the technical solutions provided in this application, the application scenarios applicable to the embodiments of this application will be explained first.

[0071] Figure 1 This application provides an embodiment of an electronic device 1000. The electronic device 1000 may include, but is not limited to, mobile phones, tablets, e-readers, remote controls, personal computers (PCs), laptops, personal digital assistants (PDAs), in-vehicle devices, smart TVs, wearable devices, televisions, smartwatches, smart bracelets, and other products with a display interface. Figure 1 The illustrated embodiment uses a mobile phone as an example of an electronic device 100 for explanation.

[0072] like Figure 1As shown, the electronic device 1000 may include a housing assembly 10 and a display screen 20, wherein the display screen 20 may be located inside the housing assembly 10. The housing assembly 10 may be used to support and protect the display screen 20. The display screen 20 may be used in active-matrix organic light-emitting diode (AMOLED) display scenarios or micro-LED display scenarios, etc., and the display screen 20 may be various self-emissive display screens, which are not limited in this application.

[0073] Figure 2 Example shown Figure 1 The diagram shows a cross-sectional view of module 20.

[0074] like Figure 2 As shown, the display screen 20 may include a cover plate 100, a display module 200, and a back plate 300. The display module 200 may be located between the cover plate 100 and the back plate 300. The cover plate 300 serves to protect the display module 200, ensuring its light-emitting performance and reliability when the display module 200 is thin, and also ensuring its bending resistance to prevent breakage. The back plate 300 provides support and secures the display module 200. For example, the cover plate 100 and the display module 200, as well as the display module 200 and the back plate 300, may be bonded using an optically clear adhesive (OCA).

[0075] In addition, the display module 200 may include a substrate 210 and an organic electroluminescent device (e.g., an OLED device) 220 disposed on the substrate 210.

[0076] Optionally, the substrate 210 can be a rigid substrate or a flexible substrate, and this application does not limit it.

[0077] For example, when the substrate 210 is a rigid substrate, the material of the substrate 210 may be one or more of the following, including but not limited to glass substrates or metal foils. When the substrate 210 is a flexible substrate, the material of the substrate 210 may be one or more of the following, including but not limited to polyethylene terephthalate, polyetheretherketone, polystyrene, polycarbonate, polyarylate, polyarylate, polyimide, polyvinyl chloride, polyethylene, or textile fibers.

[0078] The organic electroluminescent device 220 can be a current-driven light-emitting device that uses organic materials as active materials, such as organic semiconductor materials and organic light-emitting materials, which achieve light emission through carrier injection and recombination under the drive of an electric field.

[0079] Currently, commonly used organic light-emitting materials are mainly traditional fluorescent and phosphorescent materials. Among them, although fluorescent materials have the characteristics of stable properties and low cost, they are limited by the statistical law of spin quantum mechanics. Fluorescent materials can only utilize singlet excitons, which account for 25% of all excitons, while the remaining 75% of triplet excitons are deactivated through non-radiative transitions. Therefore, the maximum exciton utilization rate of fluorescent materials does not exceed 25%, resulting in low efficiency.

[0080] Phosphorescent materials can theoretically achieve 100% exciton utilization by introducing heavy metal atoms (such as iridium or platinum) and utilizing spin coupling to achieve singlet exciton transitions to triplet states. However, phosphorescent materials are primarily noble metal complexes, resulting in high production costs and hindering large-scale production. Furthermore, phosphorescent materials exhibit poor stability.

[0081] As the third generation of organic light-emitting materials following traditional fluorescent and phosphorescent materials, TADF materials can cross the reverse gap between triplet and singlet excitons, utilizing 75% triplet excitons and 25% singlet excitons, theoretically achieving a maximum exciton utilization rate of 100%. Furthermore, the molecular structure of TADF materials does not require coordination with heavy metal ions, resulting in lower costs.

[0082] For example, the molecular construction of TADF materials can involve one or more electron-donating units (D) connected by a conjugated bridge (π) and one or more electron-accepting units (A), forming a so-called twisted induced charge transfer (TICT) mechanism. The direction of this induced charge transfer is that an electron is transferred from the electron-donating unit to the electron-accepting unit through conjugation, resulting in a charge-separated excited state, thereby achieving a very small triplet-singlet energy difference (denoted as Δ in this embodiment). E ST ). Minimal △ E ST It can meet the conditions for reverse gap crossing of triplet-singlet excitons, achieving 100% exciton utilization, thus achieving the high efficiency of TADF materials.

[0083] However, in current practical applications, TADF materials constructed using the above methods still have many problems. For example, TADF materials constructed using the above methods have high efficiency and short lifetime in devices (e.g., organic electroluminescent devices 220), and high-efficiency TADF materials are still relatively scarce.

[0084] Based on the above, embodiments of this application provide an organic light-emitting compound, an organic electroluminescent device, a display screen, and an electronic device. The organic light-emitting compound uses bisfluorene as a framework and connects the main functional units at different positions of the bisfluorene, which is beneficial to obtaining superior light-emitting performance. This allows for efficient application in organic electroluminescent devices, improving the stability and efficiency of the devices and reducing the driving voltage of the devices.

[0085] The organic light-emitting compound provided in this application embodiment can be applied to the above-mentioned organic electroluminescent device 220.

[0086] It should be noted that the above application scenarios are merely examples. The organic light-emitting compounds provided in this application can also be applied to other scenarios, such as organic solar cells, organic field-effect transistors, organic thin-film transistors, organic optical detectors, organic laser diodes, or organic sensors. This application does not impose any limitations on these applications. The organic light-emitting compounds provided in the embodiments of this application are described in detail below.

[0087] This application provides an organic light-emitting compound, the chemical structure of which is shown in general formula (1): General formula (1), In the above general formula (1), Y1 and Y2 can be independently selected from any one of single bond, C(R1)2, NR1, O, S, S(=O)2, P(=O)R1, Si(R1)2 or Ge(R1)2; each Z can be independently selected from CR1 or N; Each R1 can be independently selected from hydrogen atom, deuterium atom, fluorine atom, chlorine atom, bromine atom, iodine atom, cyano group, N(=O)2, N(R2)2, OR2, SR2, C(=O)R2, P(=O)R2, Si(R2)3, or C1-C substituted with one or more deuterium atoms. 20 Alkyl groups, C2-C atoms substituted with one or more deuterium atoms 20 Alkenyl group, C2-C substituted with one or more deuterium atoms 20 Alkyne group, C6-C substituted with one or more deuterium atoms 40 aryl, or C5-C substituted with one or more deuterium atoms. 40 Any of the heteroaryl groups; or, the two R1s may be cyclically linked to form a C6-C group. 18 Aromatic rings or C5-C 18 Mixed aromatic rings, and the C6-C 18 Aromatic ring or C5-C 18 The heterocyclic aromatic ring can be optionally bound by one or more C6-C6 groups. 30 Aryl or C5-C30 heteroaryl substitution; Each R2 can be independently selected from hydrogen, deuterium, fluorine, cyano, or C1-C atoms substituted with one or more deuterium atoms. 20 Alkyl groups, C6-C atoms substituted with one or more deuterium atoms 30 aryl, or C5-C substituted with one or more deuterium atoms. 30 R3, R4, and R6 may be independently selected from any of the following groups: hydrogen atom, deuterium atom, halogen group, cyano, nitro, hydroxyl, carbonyl, ester group, imide group, amide group, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, substituted or unsubstituted alkylthio, substituted or unsubstituted arylthio, substituted or unsubstituted alkylsulfonyl, substituted or unsubstituted arylsulfonyl, substituted or unsubstituted alkenyl, substituted or unsubstituted silyl, substituted or unsubstituted boron, substituted or unsubstituted amino, substituted or unsubstituted arylphosphinyl, substituted or unsubstituted phosphine oxide, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic group. G can be selected from single bond, substituted or unsubstituted C6-C. 30 aryl, or substituted or unsubstituted C4-C 30 Any of the heteroaryl groups; A can include electron-accepting groups.

[0088] It should be noted that A including an electron-accepting group can be understood as A being an electron-accepting group, or it can be understood as A including an electron-donating group in addition to an electron-accepting group, and the electron-accepting group and the electron-donating group can be conjugated.

[0089] In the embodiments of this application, the organic light-emitting compound uses bisfluorene as a framework and connects the main functional units at different positions of bisfluorene, which is beneficial to obtain superior light-emitting performance. This enables it to be efficiently applied to organic electroluminescent devices, improves the stability and efficiency of the devices, and reduces the driving voltage of the devices.

[0090] First, the organic light-emitting compounds provided in this application achieve space charge transfer between electron-donating and electron-accepting groups by attaching electron-accepting and electron-donating groups at different positions of the bisfluorene. For example, an electron-accepting group A is attached to position 11 of the bisfluorene, and an electron-donating group is attached to at least one of positions 10 or 12 of the bisfluorene, to form a DA-type or DAD-type organic light-emitting compound with space charge transfer.

[0091] First, the electron-donating and electron-accepting groups involved in space charge transfer are connected by a non-conjugated structure, resulting in minimal overlap of electron clouds and thus a smaller Δ. E ST This facilitates the fulfillment of the reverse gap crossing conditions between triplet and singlet excitons, enabling organic light-emitting compounds to exhibit TADF characteristics and achieve 100% exciton utilization. Consequently, organic light-emitting compounds with superior optical performance and high luminous efficiency can be obtained.

[0092] Second, the complete separation of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LOMO) in organic light-emitting compounds based on space charge transfer is beneficial to improving the conversion efficiency from triplet excitons to singlet excitons and thus to obtaining highly efficient organic light-emitting compounds.

[0093] Third, compared to electron donors and electron acceptors connected by a conjugate bridge, organic light-emitting compounds based on space charge transfer have shorter emission wavelengths, which is advantageous for achieving blue light.

[0094] Fourth, since the electron clouds of electron-donating and electron-accepting groups can interact spatially, organic light-emitting compounds have a high fluorescence quantum yield, which in turn can achieve high device efficiency.

[0095] Secondly, according to the organic light-emitting compound provided in the embodiments of this application, by connecting the light-emitting center of the organic light-emitting compound to a fixed position of bisfluorene, and the substituent connected at the adjacent position of the fixed position as a steric hindrance group, it is possible to limit and block the light-emitting center, which is beneficial to prevent molecular accumulation, reduce the phosphor aggregation quenching effect, obtain a device with a narrow emission spectrum and high color purity, and improve the stability and efficiency of the device.

[0096] For example, in the embodiments of this application, A includes a conjugated electron-donating group and an electron-accepting group, which can be connected at the 11 position of the bisfluorene as the luminescent center of the organic luminescent compound. The substituents connected at the 10 and / or 12 positions of the bisfluorene can serve as steric hindrance groups of A, which helps to prevent intermolecular stacking.

[0097] Finally, the organic light-emitting compounds provided in this application use bisfluorene as a rigid framework, which helps to suppress large-amplitude molecular bond vibrations in the excited state, improve the problem of device efficiency roll-off, and enhance the device's lifetime and stability.

[0098] In some embodiments, A may be selected from any one of cyano, sulfone, carbonyl, ester, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted alkenyl, substituted or unsubstituted aralkyl, substituted or unsubstituted areneyl, substituted or unsubstituted aramine, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic.

[0099] In one example, in the organic light-emitting compound represented by general formula (1), when A includes an electron-accepting group, A can specifically be selected from any of the following groups:

[0100] In this context, R5 at each point is independently selected from hydrogen atoms, cyano groups, and substituted or unsubstituted C1-C atoms. 10 Alkyl, substituted or unsubstituted C6-C 24 Aromatic amino groups, substituted or unsubstituted C6-C 24 It is any one of aryl, substituted or unsubstituted aromatic heterol, substituted or unsubstituted pyridine, or substituted or unsubstituted thiophene.

[0101] At this time, at least one of Y1 and Y2 can be selected from any one of NR1, O, S, S(=O)2 or P(=O)R1. For example, Y1 and Y2 can both be NR1, or Y1 can be O and Y2 can be PR1. This application does not limit this.

[0102] It should be noted that at least one of Y1 and Y2 may include any of the aforementioned electron-donating groups, thereby allowing at least one electron-donating group to be attached to either the 10 or 12 position of the bisfluorene, forming a space charge transfer (DA) type organic light-emitting compound or a DAD type organic light-emitting compound with an electron-accepting group attached to the 11 position of the bisfluorene. Furthermore, compared to DA type organic light-emitting compounds, DAD type organic light-emitting compounds can achieve higher efficiency due to the additional electron-donating group on one side.

[0103] In another example, in an organic light-emitting compound represented by general formula (1), when A includes an electron-accepting group and an electron-donating group, and the electron-accepting group and the electron-donating group are conjugated, A can specifically be selected from any of the following groups:

[0104] In this context, R5 at each point is independently selected from hydrogen atoms, cyano groups, and substituted or unsubstituted C1-C atoms. 10 Alkyl, C6-C 24 Aromatic amino groups, substituted or unsubstituted C6-C 24 It is any one of aryl, substituted or unsubstituted aromatic heterol, substituted or unsubstituted pyridine, or substituted or unsubstituted thiophene.

[0105] At this point, at least one of Y1 and Y2 is selected from any one of single bond, C(R1)2, Si(R1)2, or Ge(R1)2. For example, either Y1 or Y2 can be selected, but this application does not limit this selection.

[0106] It should be noted that at least one of Y1 and Y2 is selected from any of the above-mentioned groups, which is beneficial for the substituent group connected at the 10 and / or 12 positions of the bisfluorene to serve as a steric hindrance group for the luminescent center A, so as to avoid intermolecular stacking, reduce the phosphor aggregation quenching effect, obtain devices with narrow emission spectra and high color purity, and improve the stability and efficiency of the devices.

[0107] Optionally, in the organic light-emitting compound represented by general formula (1), G can be a structure without a benzene bridge, for example, G can be a single bond. Alternatively, G can be a structure with a benzene bridge, for example, G can be selected from any of the following groups:

[0108]

[0109]

[0110]

[0111]

[0112]

[0113]

[0114]

[0115]

[0116]

[0117]

[0118]

[0119]

[0120]

[0121]

[0122]

[0123]

[0124]

[0125] In this context, R5 at each point is independently selected from hydrogen atoms, cyano groups, and substituted or unsubstituted C1-C atoms. 10 Alkyl, substituted or unsubstituted C6-C 24 Aromatic amino group, substituted or unsubstituted C6-C 24 Aryl, substituted or unsubstituted C4-C 24 Any one of heteroaryl, substituted or unsubstituted pyridine, or substituted or unsubstituted thiophene.

[0126] In some embodiments, when R6 in general formula (1) is a hydrogen atom, the chemical structure of the organic light-emitting compound provided in this application embodiment can be as shown in general formula (2): General formula (2), The relevant descriptions of Y1, Y2, Z, A, G, R3 and R4 can be found in the relevant descriptions in the above general formula (1), and will not be repeated here.

[0127] In some embodiments, the chemical structure of the organic light-emitting compound can be specifically as shown in Formula I. a ~I d As shown in any of the following:

[0128] I a I b I c

[0129] I d .

[0130] It is understandable that Equation I a ~I d The chemical structures shown are merely examples, and the chemical structures of the organic light-emitting compounds provided in the embodiments of this application are by no means limited to the above formula I. a ~I d The chemical structure shown.

[0131] It should be noted that the organic light-emitting compound is selected from Formula I above. a ~I d The chemical structure shown allows for space charge transfer between the electron-accepting group at the 11-position of bisfluorene and the electron-donating groups at the 10- and 12-positions of bisfluorene, enabling the organic light-emitting compound to exhibit TADF characteristics and achieve 100% exciton utilization. This results in organic light-emitting compounds with superior optical performance and high luminous efficiency.

[0132] In some embodiments, the chemical structure of the organic light-emitting compound can be specifically as shown in Formula I. e ~I h As shown in any of the following:

[0133] I e I f I g

[0134] I h .

[0135] It is understandable that Equation I e ~I h The chemical structures shown are merely examples, and the chemical structures of the organic light-emitting compounds provided in the embodiments of this application are by no means limited to the above formula I. e ~I h The chemical structure shown.

[0136] It should be noted that the organic light-emitting compound is selected from Formula I above. e ~I h The chemical structure shown shows that the substituents attached to the 10 and 12 positions of the bisfluorene can serve as steric hindrance groups attached to the luminescent center at the 11 position of the bisfluorene. This helps to prevent molecular accumulation, reduce the phosphor aggregation quenching effect, obtain devices with narrow emission spectra and high color purity, and improve the stability and efficiency of the devices.

[0137] The terms used in this application are explained below. Unless otherwise indicated, the following terms have the following meanings. Any undefined terms have their technically accepted meanings.

[0138] The term "substituted or unsubstituted" can refer to something that is unsubstituted or substituted by one or more substituents selected from the following: deuterium, halogen group, cyano, nitro, hydroxyl, carbonyl, ester, imide, amide, phosphine oxide, alkyl, cycloalkyl, alkoxy, aryloxy, alkylthio, arylthio, alkylsulfonyl, arylsulfonyl, alkenyl, silyl, boron, amino, arylphosphyl, aryl, aralkyl, arylenyl, alkylaryl, alkylamine, aralkylamine, heteroarylamine, arylamine, or heterocyclic. Alternatively, the term "substituted or unsubstituted" can also refer to something that is unsubstituted or substituted by a substituent linked to at least two of the substituents in the examples above. For example, "a substituent linked to at least two of the substituents in the examples above" can be a biphenyl, which can be considered as an aryl in the embodiments of this application, and can also be understood as a substitution linked to two phenyl groups.

[0139] The term "halogen group" can refer to fluorine, chlorine, bromine, or iodine.

[0140] The term "cyano" can also be called "nitrile" and can refer to the -CN group.

[0141] The term "nitro" can refer to the group -NO2.

[0142] The term "hydroxyl group" can refer to the -OH group.

[0143] The term "carbonyl" can refer to a -CO- group. In the embodiments of this application, the number of carbon atoms in the carbonyl group is not limited, and more preferably, the number of carbon atoms is 1 to 40.

[0144] The term "ester group" can refer to a -COO- group. In the embodiments of this application, the oxygen in the ester group can be substituted with a straight-chain, branched, or cyclic alkyl group having 1 to 40 carbon atoms, or with an aryl group having 6 to 30 carbon atoms.

[0145] The term "amide group" can refer to either the -CONH2 group or the -CONH- group. In the embodiments of this application, the number of carbon atoms in the amide group is not limited. Further, the number of carbon atoms is preferably 1 to 25.

[0146] The term "silyl" can be derived from the group -SiR. a R b R c Indicated. Among them, R a R b and R c Each silyl group can be independently selected from hydrogen, substituted or unsubstituted alkyl groups, or substituted or unsubstituted aryl groups; this application does not limit this selection. Examples of silyl groups may include, but are not limited to, trimethylsilyl, triethylsilyl, tert-butyldimethylsilyl, vinyldimethylsilyl, propyldimethylsilyl, triphenylsilyl, diphenylsilyl, phenylsilyl, etc.

[0147] The term "boron-based" can be derived from the group -BR a R b Indicated. Among them, R a and R b Each group can be independently selected from hydrogen, substituted or unsubstituted alkyl groups, or substituted or unsubstituted aryl groups; this application does not limit this selection. Examples of boron groups may include, but are not limited to, dimethylboryl, diethylboryl, tert-butylmethylboryl, diphenylboryl, phenylboryl, etc.

[0148] The term "alkyl" can refer to a monovalent saturated aliphatic hydrocarbon group having a carbon atom. The alkyl group can be straight-chain or branched, and there is no limitation on the number of carbon atoms in the alkyl group. For example, the number of carbon atoms can preferably be from 1 to 40. Further, the number of carbon atoms in the alkyl group can preferably be from 1 to 20, correspondingly, "C1-C..." 20 "Alkyl" refers to an alkyl group containing 1 to 20 carbon atoms in its structure. More specifically, the number of carbon atoms in an alkyl group is preferably 1 to 10. Even further, the number of carbon atoms in an alkyl group is preferably 1 to 6. Examples of alkyl groups include, but are not limited to, methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methyl-butyl, 1-ethyl-butyl, pentyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, etc. Hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl, n-heptyl, 1-methylhexyl, cyclopentylmethyl, cyclohexylmethyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 1-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 4-methylhexyl, 5-methylhexyl, etc.

[0149] The term "alkoxy" can refer to the group -O-alkyl, wherein the alkyl group is as defined in this application. Alkoxy groups can be straight-chain, branched, or cyclic, and there is no limitation on the number of carbon atoms in the alkoxy group. Further, the number of carbon atoms is preferably from 1 to 40. Examples of alkoxy groups include, but are not limited to, methoxy, ethoxy, n-propoxy, isopropoxy, isopropyloxy, n-butoxy, isobutoxy, tert-butoxy, sec-butoxy, n-pentoxy, neopentoxy, isopentoxy, n-hexyloxy, 3,3-dimethylbutoxy, 2-ethylbutoxy, n-octoxy, n-nonoxy, n-decoxy, etc.

[0150] It is understood that the substituents comprising alkyl, alkoxy, and other alkyl moieties described in the embodiments of this application may include both branched and branched forms.

[0151] The term "alkenyl" can refer to a straight-chain or branched hydrocarbon group having a carbon atom and at least one, preferably one to two, double-bonded unsaturated sites. The alkenyl group can be straight-chain or branched, and there is no limitation on the number of carbon atoms in the alkenyl group. For example, the number of carbon atoms can preferably be 2 to 40. Further, the number of carbon atoms in the alkenyl group can preferably be 2 to 20, correspondingly, "C2-C..." 20"Alkenyl" refers to an alkenyl group containing 2 to 20 carbon atoms in its structure. More specifically, the number of carbon atoms in an alkenyl group is preferably 2 to 10. Even further, the number of carbon atoms in an alkenyl group is preferably 2 to 6. Examples of alkenyl groups include, but are not limited to, vinyl, 1-propenyl, hexamyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 3-methyl-1-butenyl, 1,3-butadienyl, allyl, 1-phenylvinyl-1-yl, 2-phenylvinyl-1-yl, 2,2-diphenylvinyl-1-yl, 2-phenyl-2-(nayl-1-yl)vinyl-1-yl, styryl, etc.

[0152] The term "alkynyl" can refer to a straight-chain or branched monovalent hydrocarbon group having a carbon atom and at least one, preferably one to two, triple-bonded unsaturated sites. The alkynyl group can be straight-chain or branched, and there is no limitation on the number of carbon atoms in the alkynyl group. For example, the number of carbon atoms can preferably be 2 to 40. Further, the number of carbon atoms in the alkynyl group can preferably be 2 to 20, correspondingly, "C2-C..." 20 "Alynyl" refers to an alkynyl group containing 2 to 20 carbon atoms in its structure. More specifically, the number of carbon atoms in an alkynyl group can preferably be 2 to 10. Examples of alkynyl groups include, but are not limited to, ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, etc.

[0153] The term "cycloalkyl" can refer to a cyclic alkyl group having a monocyclic or polycyclic system including fused, bridged, and spiral rings, and there is no limitation on the number of carbon atoms in the cycloalkyl group; exemplarily, a carbon number of 3 to 60 is preferred. Further, the carbon number of the cycloalkyl group can preferably be 3 to 20. Even further, the carbon number of the cycloalkyl group can preferably be 3 to 6. Examples of cycloalkyl groups include, but are not limited to, adamantyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclooctyl, etc. For example, such cycloalkyl groups include monocyclic structures such as cyclopropyl, cyclobutyl, cyclopentyl, cyclooctyl, etc.; or polycyclic structures such as adamantyl, etc.

[0154] The number of carbon atoms in the term "alkylamino" is not limited, but more preferably, the number of carbon atoms can be from 1 to 40. Examples of alkylamino groups include, but are not limited to, methylamino, dimethylamino, ethylamino, diethylamino, phenylamino, naphthylamino, biphenylamino, anthraceneamino, 9-methyl-anthraylamino, diphenylamino, phenylnaphthylamino, xylylamino, phenyltolylamino, triphenylamino, etc.

[0155] For example, the arylamine group can be a substituted or unsubstituted monoarylamine group, a substituted or unsubstituted diarylamine group, or a substituted or unsubstituted triarylamine group. The aryl group in the arylamine group can be a monocyclic aryl or a polycyclic aryl. An arylamine group containing two or more aryl groups can contain monocyclic aryl and / or polycyclic aryl groups.

[0156] Specifically, examples of arylamine groups may include, but are not limited to, phenylamine, naphthylamine, biphenylamine, anthraceneamine, 3-methyl-phenylamine, 4-methyl-naphthylamine, 2-methyl-biphenylamine, 9-methyl-anthraylamine, diphenylamine, phenylnaphthylamine, xylylamine, phenyltolylamine, carbazole, triphenylamine, etc.

[0157] For example, the heteroarylamine group can be a substituted or unsubstituted mono-heteroarylamine group, a substituted or unsubstituted di-heteroarylamine group, or a substituted or unsubstituted tri-heteroarylamine group. The heteroaryl group in the heteroarylamine group can be a monocyclic heteroaryl or a polycyclic heteroaryl. A heteroarylamine group containing two or more heteroaryl groups can contain monocyclic heteroaryl and / or polycyclic heteroaryl.

[0158] For example, the arylphosphine group can be a substituted or unsubstituted monoarylphosphine group, a substituted or unsubstituted diarylphosphine group, or a substituted or unsubstituted triarylphosphine group. The aryl group in the arylphosphine group can be a monocyclic aryl or a polycyclic aryl. An arylphosphine group containing two or more aryl groups can contain monocyclic aryl and / or polycyclic aryl groups.

[0159] The term "aryl" can refer to a monovalent aromatic carbocyclic group having a single ring (such as that present in a phenyl group) or a ring system having multiple condensed rings (examples of such aromatic ring systems include naphthyl, anthracene, and indene), wherein the condensed rings may or may not be aromatic, provided that the attachment point is via an atom of an aromatic ring. Furthermore, there is no limitation on the number of carbon atoms in the aryl group; more preferably, the number of carbon atoms is 6 to 60. Even further, the number of carbon atoms in the aryl group can preferably be 6 to 30, correspondingly, "C6-C..." 30 "Aryl" refers to an aryl group containing 6 to 30 carbon atoms in its structure. Examples of monocyclic aryl groups include, but are not limited to, phenyl, biphenyl, and terphenyl, while examples of polycyclic aryl groups include, but are not limited to, naphthyl, anthracene, phenanthryl, pyrene, peryl, indene, thionyl, fluorene, and triphenylene.

[0160] The term "heteroaryl" can refer to "an aromatic group having a carbon atom and a heteroatom selected from at least one of the groups O, N, P, S, Si, and Se within a ring, and there is no limitation on the number of carbon atoms in the heteroaryl group. Further, it is preferred that the number of carbon atoms be 5 to 30, and the number of heteroatoms be 1 to 10. Accordingly, "C5-C..." 30"Heteroaryl" refers to a heteroaryl group containing 5 to 30 carbon atoms in its structure. Such heteroaryl groups may have a monocyclic ring (such as pyridyl, imidazolyl, or furanyl) or multiple condensed rings in a ring system (e.g., in groups such as indolazinyl, quinolinyl, benzofuran, benzimidazolyl, or benzothiophene), wherein at least one ring in the ring system is aromatic.

[0161] The term "heterocyclic group" can refer to a saturated or unsaturated group having a monocyclic or multiple condensed rings (including fused, bridged, and spirocyclic systems) and ring atoms, and comprising heteroatoms from the group consisting of at least one of O, N, P, S, Si, and Se. These ring atoms are selected from N, S, or O, wherein in fused ring systems, one or more rings can be cycloalkyl, aryl, or heteroaryl, provided that the attachment point is via a non-aromatic ring. In some embodiments, the N and / or S atoms of the heterocyclic group may optionally be oxidized to provide an N-oxide, -S(O)-, or -SO2- module. There is no limitation on the number of carbon atoms in the heterocyclic group. Further, it is preferred that the number of carbon atoms can be from 1 to 30, and the number of heteroatoms can be from 1 to 10.

[0162] Examples of heterocyclic and heteroaryl groups may include, but are not limited to, pyridinyl, pyrroloyl, pyrimidinyl, pyridazinyl, furanyl, thiopheneyl, imidazoleyl, pyrazolyl, oxazolyl, isoxazolyl, triazolyl, oxadiazolyl, thiadiazolyl, dithiazolyl, tetrazolyl, pyranyl, quinazinyl, oxazinyl, thiazidinyl, dioxinyl, triazinyl, tetraazinyl, quinolinyl, isoquinoline, quinazolinyl, quinoxalinyl, naphthidyl, acridineyl, globulinyl, phenanthridineyl, and diazinonyl. Azanaphthyl, triazaindyl, ganzolyl, dihydroindolyl, ganzozinyl, acridinepyrimidinyl, pyridopyrazinyl, pyrazinopyrazinyl, benzothiazolyl, benzooxazolyl, benzoimidazolyl, benzothiopheneyl, benzofuranyl, dibenzothiopheneyl, dibenzofuranyl, carbazolyl, benzocarbazolyl, dibenzocarbazolyl, indoloindolyl, phthalazinyl, imidazopyrimidinyl, phenothiazinyl, piperidinyl, piperazinyl, imidazopyridinyl, indolazinyl, etc.

[0163] The term "aryloxy group" can refer to the group -O-aryl, wherein aryl is defined as described above in the embodiments of this application, and for example includes phenoxy, naphthoxy, etc.

[0164] In the embodiments of this application, the above description of aryl groups can also be applied to aryl groups among arylthio, arylsulfonyl, arylphosphinyl, arylalkyl, arylalkylamine, arylenyl, alkylaryl, arylamine, and arylheteroarylamine.

[0165] In the embodiments of this application, the above description of heteroaryl groups can be applied to heteroaryl amines and heteroaryl heteroaryl amines.

[0166] In the embodiments of this application, the above description of alkenyl groups can be applied to alkenyl groups in aryl groups.

[0167] In the embodiments of this application, the above description of aryl groups can be applied to arylene groups, the difference being that arylene groups are divalent. Correspondingly, "C6-C..." 30 "Aryl" can refer to an aryl group containing 6 to 30 carbon atoms in its structure.

[0168] In the embodiments of this application, the above description of heteroaryl groups can be applied to heteroaryl groups, the difference being that heteroaryl groups are divalent. Accordingly, "C4-C..." 30 "Hypoaryl" can refer to a heteroaryl group containing 4 to 30 carbon atoms in its structure.

[0169] In this embodiment of the application, "two R1 rings are connected to form C6-C" 18 Aromatic rings or C5-C 18 "Heteroaromatic ring" can be understood as a ring system in which, apart from the monovalent substituent at the end of the structure, two adjacent ring atoms in the same ring system are both attached to R1. These two R1s, together with the two ring atoms attached to them, can form a new ring system that fuses with the aforementioned ring system, such as C6-C. 18 Aromatic rings or C5-C 18 A heterocyclic aromatic ring. Furthermore, this new ring system can be further converted by one or more C6-C... 30 Aryl or C5-C 30 heteroaryl substitution.

[0170] This application provides an exemplary method for preparing an organic light-emitting compound as shown in general formula (1).

[0171] [Preparation Reaction Formula]

[0172] According to the above preparation reaction formula, the m-dimethyldiphenyl halo derivative is first oxidized with an oxidant to obtain a m-diphenylm-dicarboxylic acid halobenzene derivative, and then a cyclization reaction is carried out using a strong acid to obtain a haloindrone fluorene dione derivative. The haloindrone fluorene dione derivative is borate esterified using a Pd catalyst, and then cross-coupled with a halofunctional group to obtain a diketone intermediate. Finally, the diketone intermediate is subjected to a lithium halide exchange reaction (or Grignard reaction) and a cyclization reaction to obtain an organic light-emitting compound as shown in general formula (1).

[0173] In the compounds shown in the above preparation reaction formulas, X is a halogen atom, such as a bromine atom or a chlorine atom. The relevant descriptions of A, G, R1~R6, Y1 and Y2 can be found in the general formula (1) defined in the above description of organic light-emitting compounds, and will not be repeated here.

[0174] It is understood that the above-described reaction formulas for the preparation of organic light-emitting compounds are merely examples and are not intended to limit this application.

[0175] This application provides an application of the above-mentioned organic light-emitting compound, which has excellent light-emitting properties and can be used to prepare organic electroluminescent devices or as a dopant in organic electroluminescent devices.

[0176] It should be noted that the above-mentioned organic light-emitting compounds can also be used to prepare other electronic devices according to actual needs, such as organic solar cells, organic field-effect transistors, organic thin-film transistors or organic laser diodes, etc., and this application does not limit them.

[0177] This application provides an organic electroluminescent device based on the above-mentioned organic light-emitting compound.

[0178] The following is combined Figure 3 and Figure 4 This application provides a detailed description of the organic electroluminescent device provided in its embodiments. Figure 3 and Figure 4 These are schematic diagrams illustrating the structure of an organic electroluminescent device 300 provided in embodiments of this application. It can be understood that the organic electroluminescent device 300 can be... Figure 2 The organic electroluminescent device 220 shown is shown.

[0179] See also Figure 3 and Figure 4 The organic electroluminescent device 300 can be disposed on the substrate 400, and the substrate 400 can be... Figure 2 The substrate 210 shown.

[0180] The organic electroluminescent device 300 may include a first electrode 310 and a second electrode 330 disposed opposite to each other, and an organic layer 320 located between the first electrode 310 and the second electrode 330. The first electrode 310 may be located on a substrate 400, and the organic layer 320 may include a light-emitting layer 324, which may include the aforementioned organic light-emitting compound.

[0181] The light-emitting layer 324 can be a layer in the organic electroluminescent device 300 that gathers a considerable concentration of electrons and holes and provides a site for exciton formation and light emission.

[0182] In some embodiments, the light-emitting layer 324 may include a light-emitting material, a sensitizing material, and a host material. Optionally, at least one of the sensitizing material and the light-emitting material may include the aforementioned organic light-emitting compound, or the host material may also include the aforementioned organic light-emitting compound; this application does not impose any limitations on this.

[0183] It should be noted that the first electrode 310 can be an anode and the second electrode 330 can be a cathode, or the first electrode 310 can be a cathode and the second electrode 330 can be an anode; this application does not impose any limitations on this. For ease of description, in the embodiments of this application, the first electrode 310 is used as the anode and the second electrode 330 as the cathode as an example for illustration.

[0184] It can be understood that in the organic electroluminescent device 300, when a bias voltage is applied to the first electrode 310 and the second electrode 330, electrons are injected from the second electrode 330 (cathode) into the light-emitting layer 324 and transferred from the light-emitting layer 324 to the first electrode 310 (anode), or holes are injected from the light-emitting layer into the first electrode 310 (anode). When holes and electrons combine in the light-emitting layer 324 to form singlet or triplet excitons, light emission is generated.

[0185] In some embodiments, such as Figure 3 As shown, the organic layer 320 may further include a hole injection layer 321, a hole transport layer 322, an electron blocking layer 323, a hole blocking layer 325, an electron transport layer 326, and an electron injection layer 327, which are stacked sequentially. The hole injection layer 321 may be located on the side of the first electrode 310 facing the second electrode 330, and the electron injection layer 327 may be located on the side of the second electrode 330 facing the first electrode 310. The light-emitting layer 324 may be located between the electron blocking layer 323 and the hole blocking layer 325.

[0186] The hole injection layer 321 can be a layer in the organic electroluminescent device 300 that is in contact with the anode, promoting the entry of holes from the anode into the light-emitting layer 324. This layer can also prevent excitons generated in the light-emitting layer 324 from moving to the electron injection layer 327. The hole transport layer 322 can be a layer in the organic electroluminescent device 300 that drives holes from the anode to the charge recombination site. This layer does not need to be in contact with the anode. The electron blocking layer 323 can be a layer in the organic electroluminescent device 300 used to block electrons from the cathode at the interface of the light-emitting layer 324, thereby increasing the electron concentration at the interface of the light-emitting layer 324. The hole blocking layer 325 can be a layer in the organic electroluminescent device 300 used to block holes from the anode at the interface of the light-emitting layer 324, thereby increasing the hole concentration at the interface of the light-emitting layer 324. Electron transport layer 326 may be a layer in the organic electroluminescent device 300 that drives electrons from the cathode to the charge junction. This layer may not need to be in contact with the cathode and often may not be an effective hole transporter, thus it can be used to block holes from moving towards the cathode. Electron injection layer 327 may be a layer in the organic electroluminescent device 300 that is in contact with the cathode and promotes electrons from the cathode into the light-emitting layer 324.

[0187] Specifically, in some embodiments, at least one of the hole injection layer 321, hole transport layer 322, electron blocking layer 323, hole blocking layer 325, electron transport layer 326, and electron injection layer 327 may include the aforementioned TADF compound. For example, hole injection layer 321 and electron blocking layer 323 may include the aforementioned organic light-emitting compound. As another example, hole transport layer 323 and electron injection layer 327 may include the aforementioned organic light-emitting compound. Yet another example, hole injection layer 321, electron transport layer 323, and electron injection layer 327 may include the aforementioned organic light-emitting compound; this application does not impose any limitations on this.

[0188] It should be noted that, in the embodiments of this application, the organic electroluminescent device 300 may not be limited to the above structure. For example, the organic layer 320 may only include the light-emitting layer 324, or the organic layer 320 may include at least one of the following in addition to the light-emitting layer 324: hole injection layer 321, hole transport layer 322, electron blocking layer 323, hole blocking layer 325, electron transport layer 326, and electron injection layer 327.

[0189] In one example, such as Figure 4 As shown, the organic layer 320 may include an electron blocking layer 323 and a light-emitting layer 324 stacked sequentially. The electron blocking layer 323 may be located on the side of the first electrode 310 facing the second electrode 330, and the light-emitting layer 323 may be located on the side of the second electrode 330 facing the first electrode 310.

[0190] For example, the electron blocking layer 323 may include the organic light-emitting compound described above.

[0191] In another example, the organic layer 320 may include a hole transport layer 322, an electron blocking layer 323, a light-emitting layer 324, and an electron transport layer 326 (not shown in the figure) stacked sequentially. The hole transport layer 322 may be located on the side of the first electrode 310 facing the second electrode 330, and the electron transport layer 325 may be located on the side of the second electrode 330 facing the first electrode 310.

[0192] For example, at least one of the hole transport layer 322, electron blocking layer 323, and electron transport layer 326 may include the aforementioned TADF compound. For instance, hole transport layer 322 and electron blocking layer 323 may include the aforementioned organic light-emitting compound. As another example, electron blocking layer 323 and electron transport layer 326 may include the aforementioned organic light-emitting compound.

[0193] In yet another example, the organic layer 320 may consist only of the light-emitting layer 324 (not shown in the figure).

[0194] It is understood that the structure of the organic layer 320 described above is merely an example and not a limitation of this application.

[0195] It should be noted that, apart from the organic layer 320 including the organic light-emitting compound described above, that is, apart from the organic layer 320 including the organic light-emitting compound shown in the general formula (1) above, the organic electroluminescent device 300 provided in this application embodiment can be manufactured by materials and methods known in the art.

[0196] Furthermore, in some embodiments, when the organic electroluminescent device 300 includes a plurality of organic layers 320, the plurality of organic layers 320 may be composed of the same material or different materials, and this application does not limit this.

[0197] The following is an example of a method for fabricating an organic electroluminescent device 300.

[0198] In one example, the organic electroluminescent device 300 can be fabricated by sequentially stacking a first electrode 310 (anode), an organic layer 320, and a second electrode 330 (cathode) on a substrate 400. Specifically, the first electrode 310 (anode) can be formed by depositing a metal or a conductive metal oxide or alloy on the substrate 400 using a physical vapor deposition method (e.g., sputtering or electron beam evaporation). Then, a hole injection layer 321, a hole transport layer 322, an electron blocking layer 323, a light-emitting layer 324, a hole blocking layer 325, an electron transport layer 326, and an electron injection layer 327 can be sequentially deposited on the first electrode 310 using the same method. Finally, the cathode material is deposited on the electron injection layer 326 to form the second electrode 330 (cathode) using the same method.

[0199] In another example, the organic electroluminescent device 300 can be fabricated by sequentially stacking a second electrode 330 (cathode), an organic layer 320, and a first electrode 330 (anode) on a substrate 400.

[0200] It is understood that the above-described method for preparing the organic electroluminescent device 300 is merely an example. The organic electroluminescent device 300 can also be prepared by other methods in the embodiments of this application, and this application does not limit it.

[0201] Next, we will introduce in detail the materials of each layer structure in the organic electroluminescent device 300.

[0202] Suitable materials for the anode may include electrode materials with a high power function, such as metals or alloys thereof, including vanadium, chromium, copper, zinc, gold, etc., or metal oxides such as zinc oxide, indium oxide, tin oxide, indium tin oxide (ITO), indium zinc oxide, antimony oxide, zinc indium tin oxide, etc., or combinations of metals and oxides such as ZnO:Al or SnO2:Sb; or conductive polymers such as poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxo)thiophene], polypyrrole, polyaniline, etc., which are not limited in this application. Preferably, ITO is often used as the anode because it is transparent to light propagation, thus facilitating the escape of light emitted from the electroactive organic layer.

[0203] Suitable materials for the cathode may include electrode materials with a low power function, such as metals or alloys and mixtures thereof, including lithium, sodium, cesium, magnesium, calcium, strontium, barium, aluminum, silver, gold, indium, tin, zinc, zirconium, scandium, yttrium, etc. Suitable alloy materials for the cathode may exemplarily include silver-magnesium, aluminum-lithium, indium-magnesium, aluminum-calcium, and aluminum-gold alloys. Layered non-alloy structures may also be used in the cathode, for example, by coating a thin layer of calcium or a metal fluoride (such as lithium fluoride) with a layer of zero-valent metal (e.g., aluminum or silver). Preferably, the cathode may be composed of a single zero-valent metal, such as aluminum.

[0204] Suitable materials for the hole injection layer 321 may include materials with hole injection properties, wherein the highest occupied molecular orbital of the material may lie between the work function of the anode material and the highest occupied molecular orbital of the surrounding organic material layer, such as the electron blocking layer 323. For example, the material of the hole injection layer 321 may include, but is not limited to, metalloporphyrins, oligothiophenes, arylamine-based organic materials, and polythiophene-based conductive polymers. It is understood that the luminescent compound represented by the general formula (1) provided in the embodiments of this application may replace or be added to the above-mentioned substances.

[0205] Materials suitable for use in hole transport layer 322 may include materials with hole transport properties, such as compounds containing m-carbazole phenyl groups, various triphenylamine trimers and tetramers, etc. It is understood that the organic light-emitting compounds of the above general formula (1) provided in the embodiments of this application may replace or be added to the above substances.

[0206] Materials suitable for use in electron blocking layer 323 may include compounds with electron blocking properties, such as, but not limited to, carbazole derivatives, compounds having triphenylmethane silyl and triarylamine structures, monoamine compounds with high electron blocking properties, and various triphenylamine dimers. It is understood that the organic light-emitting compounds of the above general formula (1) provided in the embodiments of this application may replace or be added to the above substances.

[0207] The luminescent layer 324 may include a host material and a dopant material, and the dopant material may include doped luminescent material and doped sensitizing material. The triplet energy of the host material may be greater than the triplet energy of the dopant material.

[0208] The host material may include, but is not limited to, thiazole derivatives, benzimidazole derivatives, polydialkylfluorene derivatives, and heterocyclic compounds with a partial structure having an indole ring as a fused ring. It is understood that the organic light-emitting compound represented by the above general formula (1) provided in the embodiments of this application may be added to the above substances.

[0209] In the embodiments of this application, the doped luminescent material may include an organic luminescent compound as shown in general formula (1): General formula (1), In one example, Y1 and Y2 can both be O, multiple Z can all be CR1, where R1, R3, R4 and R6 are all hydrogen atoms, G is a single bond, and A is 4,6-diphenyl-1,3,5-triazine.

[0210] In another example, Y1 can be NR1, Y2 can be S, and multiple Zs can be CR1, where R1, R3, R4, and R6 are all hydrogen atoms, G is a single bond, and A is 2,6-diphenylpyrimidine.

[0211] In yet another example, Y1 can be NR1, Y2 can be P(=O)R1, and multiple Zs can be CR1, where R1, R3, R4, and R6 are all hydrogen atoms, G is phenyl, and A is 2,6-diphenyl sulfone.

[0212] In some embodiments, the doped luminescent material may include other substances in addition to organic luminescent compounds as shown in general formula (1), such as aromatic amine derivatives, styrene amine compounds, metal complexes, etc.

[0213] In the embodiments of this application, the doped sensitizing material may include an organic light-emitting compound as shown in general formula (1). It is understood that, in addition to the organic light-emitting compound as shown in general formula (1), other substances may also be incorporated into the doped sensitizing material, and this application does not limit this.

[0214] Materials suitable for use in hole blocking layer 325 may include compounds with hole blocking properties, such as, but not limited to, phenanthrenepyrrole derivatives such as 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi), metal complexes such as quinolinol derivatives, and various rare earth complexes, oxazole derivatives, triazole derivatives, and other compounds with steric hindrance. It is understood that the organic light-emitting compounds of the above general formula (1) provided in the embodiments of this application may replace or be added to the above substances.

[0215] Materials suitable for use in electron transport layer 326 may include, but are not limited to, Al complexes of 8-hydroxyquinoline, complexes containing Alq3, organic free radical compounds, etc. It is understood that the organic light-emitting compounds of the above general formula (1) provided in the embodiments of this application may replace or be added to the above substances.

[0216] Materials suitable for use in electron injection layer 327 may include materials with electron transport properties, such as, but not limited to, fluorenone, anthraquinone dimethane, biphenylquinone, thiamethane dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fluorenemethane, anthrone, and their derivatives, metal complex compounds, nitrogen-containing 5-membered ring derivatives, etc.

[0217] According to the organic electroluminescent device 300 provided in the embodiments of this application, the light-emitting layer 324 in the organic electroluminescent device 300 may include the organic light-emitting compound shown in general formula (1) above. The organic light-emitting compound uses bisfluorene as a framework and connects the main functional units at different positions of bisfluorene, which is beneficial to obtaining better light-emitting performance, thereby enabling efficient application in organic electroluminescent devices, improving the stability and efficiency of the device, and reducing the driving voltage of the device.

[0218] The embodiments of this application will be further described below with reference to several examples. It will be understood that the advantages of the embodiments of this application will be set forth in part in the following description, and in part will be obvious from the description, or may be learned by practicing the embodiments of this application.

[0219] [Example 1] Synthesis of Compound 1:

[0220]

[0221]

[0222] Reactants II-1 (10.11 g, 30 mmol) and II-2 (9.48 g, 60 mmol) were placed in a 1 L round-bottom flask, and 500 mL of tert-butanol was added. The mixture was heated to 80 °C and stirred overnight. After the reaction was complete, the temperature was lowered to room temperature, filtered with a large amount of hot water, and then acidified with 2 M hydrochloric acid. The filtered product yielded intermediate II-3. Intermediate II-3 was placed in a 100 mL round-bottom flask, 20 mL of methanesulfonic acid was added, and the mixture was heated to 80 °C and maintained at this temperature for 3 hours. The temperature was then lowered to room temperature. The resulting mixture was added to ice water, filtered, and then subjected to silica gel column chromatography using a mixture of dichloromethane and petroleum ether as eluent to obtain intermediate II-4 (2.18 g), with a yield of approximately 20%.

[0223] The mass spectrometry (MS) analysis of intermediate II-4 yielded the following results: MS[M+H]. + =361.

[0224] Under nitrogen protection, intermediate II-4 (3.60 g, 10 mmol), bis(pinacolyl)diboron (5.06 g, 20 mmol), 1,1'-bis(diphenylphosphino)ferrocene palladium dichloride (366 mg, 0.5 mmol), and anhydrous potassium acetate (1.96 g, 20 mmol) were placed in a 100 mL round-bottom flask, and 40 mL of anhydrous dioxane was added. The mixture was heated to 120 °C and stirred overnight. After the reaction was complete, the temperature was lowered to room temperature, the solvent was evaporated, and silica gel column chromatography was performed using a mixture of dichloromethane and petroleum ether as eluent to obtain intermediate II-5 (2.45 g), with an overall yield of approximately 60%.

[0225] The MS analysis result of intermediate II-5 was [M+H]. + =409.

[0226] Under nitrogen protection, intermediate II-5 (4.80 g, 10 mmol), reactant II-6 (3.76 g, 10 mmol), tetraphenylphosphine palladium (575 mg, 0.5 mmol), and anhydrous potassium carbonate (2.76 g, 10 mmol) were placed in a 250 mL round-bottom flask, and 100 mL of a mixed solvent of tetrahydrofuran and water (volume ratio 5:1) was added. The mixture was heated to 75 °C and stirred overnight. After the reaction was complete, the temperature was lowered to room temperature, the solvent was evaporated, and silica gel column chromatography was performed using a mixture of dichloromethane and petroleum ether as eluent to obtain intermediate II-7 (3.76 g) in approximately 65% ​​yield.

[0227] The MS analysis result of intermediate II-7 was [M+H]. +=578.

[0228] Under nitrogen protection, reactant II-8 (2-bromotriphenylamine) (4.84 g, 15 mmol) was placed in a 250 mL two-necked flask, dissolved in 75 mL of anhydrous tetrahydrofuran solution, and then placed at -78 °C. 2.4 M n-butyllithium solution (8.12 mL, 19.5 mmol) was added dropwise, and the mixture was stirred at -78 °C for 1 hour. Then, intermediate II-7 (8.76 g, 15 mmol) was added, and the mixture was stirred overnight. The mixture was then quenched with 10 mL of distilled water. The tetrahydrofuran was removed from the reaction solution under reduced pressure, and the mixture was extracted three times with 40 mL of dichloromethane. The dichloromethane was removed again under reduced pressure, and the mixture was recrystallized with ethanol. After filtration and drying, intermediate II-9 was obtained. Intermediate II-9 was placed in a 250 mL flask, 100 mL of acetic acid was added, and the mixture was stirred for 10 minutes. Then, 3 mL of concentrated hydrochloric acid was added, and the mixture was heated to 110 °C and refluxed for 3 hours. After the reaction was completed, the temperature was lowered to room temperature, and the reaction solution was poured into 500 mL of ice water to precipitate the product. After filtration, the product was subjected to silica gel column chromatography with dichloromethane and petroleum ether as eluent to obtain compound 1 (10.08 g, 10.50 mmol), with a yield of approximately 70%.

[0229] The MS analysis result for compound 1 was MS[M+H]. + =1033.

[0230] Fabrication of an organic electroluminescent device: A transparent conductive glass substrate sputtered with ITO was ultrasonically cleaned in distilled water containing a cleaning agent. After washing with ITO for 30 minutes, ultrasonic cleaning was repeated twice with deionized water, each time for 10 minutes. Then, ultrasonic cleaning was performed using isopropanol, acetone, and methanol solvents, followed by drying. The substrate was then transferred to a plasma cleaner for 6 minutes, and then to a vacuum evaporator, where a vacuum of 1 × 10⁻⁶ was applied. -7 ~5×10 -6 Pa.

[0231] Then, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazabenzophenanthrene (HAT-CN) was deposited on the glass substrate with the ITO electrode to form a hole injection layer with a thickness of 10 nm. 1'-biphenyl-4-4'-diamine (NPB) was then deposited on the hole injection layer to form a hole transport layer with a thickness of 40 nm. Subsequently, 4,4',4”-tris(carbazole-9-yl)triphenylamine (TCAT) was deposited on the hole transport layer to form an electron blocking layer with a thickness of 10 nm.

[0232] Next, 3,3'-bis(9H-carbazole-9-yl)-1,1'-biphenyl (mCBP) was deposited on the electron blocking layer to form an 8 nm thick layer. Then, compound 1 and 2,8-bis(diphenylphospho)dibenzo[b,d]furan (PPF) were mixed and deposited on the formed mCBP layer at a weight ratio of 3:17 (compound 1 accounted for 15% by weight) to form a 20 nm thick luminescent layer, wherein compound 1 was used as the dopant luminescent material and PPF was used as the host material. PPF was then deposited on the luminescent layer to form a 10 nm thick hole blocking layer. Finally, 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi) was deposited on the hole blocking layer to form a 40 nm thick electron transport layer. Finally, lithium 8-hydroxyquinoline (Liq) and metallic aluminum are sequentially deposited on the electron transport layer to form an electron injection layer with a thickness of 2 nm and a cathode with a thickness of 120 nm.

[0233] In the above process, the hole injection layer and electron injection layer can be deposited at a deposition rate of 0.04 m / s to 0.07 nm / s, while the hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, and electron transport layer can be deposited at a deposition rate of 0.2 nm / s to 0.4 nm / s. The cathode can be deposited at a deposition rate of 0.6 nm / s to 0.9 nm / s, thereby obtaining an organic electroluminescent device.

[0234] [Example 2] Preparation of compound 1: The preparation method of compound 1 in this embodiment is the same as that of compound 1 in Example 1.

[0235] Fabrication of an organic electroluminescent device: In this embodiment, an organic electroluminescent device was prepared using the same method as in Example 1, except that in this embodiment, compound 1 and PPF were mixed and vapor-deposited at a weight ratio of 1:4 (the weight ratio of compound 1 was 20%) to form a light-emitting layer with a film thickness of 20 nm.

[0236] [Example 3] Preparation of compound 1: The preparation method of compound 1 in this embodiment is the same as that of compound 1 in Example 1.

[0237] Fabrication of an organic electroluminescent device: In this embodiment, an organic electroluminescent device was prepared using the same method as in Example 1, except that in this embodiment, compound 1 and PPF were mixed and vapor-deposited at a weight ratio of 1:3 (the weight ratio of compound 1 was 25%) to form a light-emitting layer with a film thickness of 20 nm.

[0238] [Example 4] Preparation of compound 1: The preparation method of compound 1 in this embodiment is the same as that of compound 1 in Example 1.

[0239] Fabrication of an organic electroluminescent device: In this embodiment, an organic electroluminescent device was prepared using the same method as in Example 1, except that in this embodiment, compound 1 and PPF were mixed and vapor-deposited in a weight ratio of 3:7 (the weight ratio of compound 1 was 30%) to form a light-emitting layer with a thickness of 20 nm.

[0240] [Comparative Example 1] Preparation of compound 1:

[0241]

[0242] Under nitrogen protection, reactant III-1 (2.59 g, 10 mmol), bis(pinacolyl)diboron (5.06 g, 20 mmol), 1,1'-bis(diphenylphosphino)ferrocene palladium dichloride (366 mg, 0.5 mmol), and anhydrous potassium acetate (1.96 g, 20 mmol) were placed in a 100 mL round-bottom flask, and 40 mL of anhydrous dioxane was added. The mixture was heated to 120 °C and stirred overnight. After the reaction was complete, the temperature was lowered to room temperature, the solvent was evaporated, and then silica gel column chromatography was performed using a mixture of dichloromethane and petroleum ether as eluent to obtain intermediate III-2 (1.95 g), with a total yield of approximately 65%.

[0243] The MS analysis result of intermediate III-2 was MS[M+H]. + =307.

[0244] Under nitrogen protection, intermediate III-2 (3.06 g, 10 mmol), reactant III-3 (3.76 g, 10 mmol), tetraphenylphosphine palladium (575 mg, 0.5 mmol), and anhydrous potassium carbonate (2.76 g, 10 mmol) were placed in a 250 mL round-bottom flask, and 100 mL of a mixed solvent of tetrahydrofuran and water (volume ratio 5:1) was added. The mixture was heated to 75 °C and stirred overnight. After the reaction was complete, the temperature was lowered to room temperature, the solvent was evaporated, and silica gel column chromatography was performed using a mixture of dichloromethane and petroleum ether as eluent to obtain intermediate III-4 (2.85 g), with a yield of approximately 60%.

[0245] The MS analysis result of intermediate III-4 was MS[M+H]. +=477.

[0246] Under nitrogen protection, reactant III-5 (2-bromotriphenylamine) (4.84 g, 15 mmol) was placed in a 250 mL two-necked flask, dissolved in 75 mL of anhydrous tetrahydrofuran solution, and then placed at -78 °C. 2.4 M n-butyllithium solution (8.12 mL, 19.5 mmol) was added dropwise, and the mixture was stirred at -78 °C for 1 hour. Then, intermediate III-4 (7.16 g, 15 mmol) was added, and the mixture was stirred overnight. The mixture was then quenched with 10 mL of distilled water. The tetrahydrofuran was removed from the reaction solution under reduced pressure, and the mixture was extracted three times with 40 mL of dichloromethane. The dichloromethane was removed again under reduced pressure, and the mixture was recrystallized with ethanol. After filtration and drying, intermediate III-6 was obtained. Intermediate III-6 was placed in a 250 mL flask, 100 mL of acetic acid was added, and the mixture was stirred for 10 minutes. Then, 3 mL of concentrated hydrochloric acid was added, and the mixture was heated to 110 °C and refluxed for 3 hours. After the reaction was completed, the temperature was lowered to room temperature, and the reaction solution was poured into 500 mL of ice water to precipitate the product. After filtration, the product was subjected to silica gel column chromatography with dichloromethane and petroleum ether as eluent to obtain the control compound 1 (6.33 g, 9.02 mmol), with a yield of approximately 60%.

[0247] The MS analysis result of comparison compound 1 is MS[M+H]. + =704.

[0248] Preparation of an organic electroluminescent layer: In this embodiment, an organic electroluminescent device was prepared using the same method as in Example 1, except that in this embodiment, comparative compound 1 was used instead of compound 1, and comparative compound 1 and PPF were mixed and vapor-deposited at a weight ratio of 1:19 (the weight ratio of comparative compound 1 was 5%) to form a light-emitting layer with a film thickness of 20 nm. In this embodiment, the comparative compound was used as a doped light-emitting material, and PPF was used as the host material.

[0249] [Comparative Example 2] Preparation of compound 1: The preparation method of comparative compound 1 in this embodiment is the same as that of comparative compound 1 in comparative example 1.

[0250] Preparation of an organic electroluminescent layer: In this embodiment, an organic electroluminescent device was prepared using the same method as in Example 1, except that in this embodiment, comparative compound 1 was used instead of compound 1, and comparative compound 1 and PPF were mixed and vapor-deposited at a weight ratio of 1:9 (the weight ratio of comparative compound 1 was 10%) to form a light-emitting layer with a film thickness of 20 nm.

[0251] [Comparative Example 3] Preparation of compound 1: The preparation method of comparative compound 1 in this embodiment is the same as that of comparative compound 1 in comparative example 1.

[0252] Preparation of an organic electroluminescent layer: In this embodiment, an organic electroluminescent device was prepared using the same method as in Example 1, except that in this embodiment, comparative compound 1 was used instead of compound 1, and comparative compound 1 and PPF were mixed and vapor-deposited at a weight ratio of 3:17 (comparative compound 1 was 15% by weight) to form a light-emitting layer with a film thickness of 20 nm.

[0253] [Comparative Example 4] Preparation of compound 1: The preparation method of comparative compound 1 in this embodiment is the same as that of comparative compound 1 in comparative example 1.

[0254] Preparation of an organic electroluminescent layer: In this embodiment, an organic electroluminescent device was prepared using the same method as in Example 1, except that in this embodiment, comparative compound 1 was used instead of compound 1, and comparative compound 1 and PPF were mixed and vapor-deposited at a weight ratio of 1:4 (the weight ratio of comparative compound 1 was 20%) to form a light-emitting layer with a film thickness of 20 nm.

[0255] [Comparative Example 5] Preparation of compound 1: The preparation method of comparative compound 1 in this embodiment is the same as that of comparative compound 1 in comparative example 1.

[0256] Preparation of an organic electroluminescent layer: In this embodiment, an organic electroluminescent device was prepared using the same method as in Example 1, except that in this embodiment, comparative compound 1 was used instead of compound 1, and comparative compound 1 and PPF were mixed and vapor-deposited at a weight ratio of 1:3 (the weight ratio of comparative compound 1 was 25%) to form a light-emitting layer with a film thickness of 20 nm.

[0257] [Comparative Example 6] Preparation of compound 1: The preparation method of comparative compound 1 in this embodiment is the same as that of comparative compound 1 in comparative example 1.

[0258] Preparation of an organic electroluminescent layer: In this embodiment, an organic electroluminescent device was prepared using the same method as in Example 1, except that in this embodiment, comparative compound 1 was used instead of compound 1, and comparative compound 1 and PPF were mixed and vapor-deposited at a weight ratio of 3:7 (the weight ratio of comparative compound 1 was 30%) to form a light-emitting layer with a film thickness of 20 nm.

[0259] Using the organic electroluminescent devices prepared in Examples 1 to 4 and Comparative Examples 1 to 6 as experimental subjects, the obtained organic electroluminescent devices were tested by applying electricity, and the data results are shown in Table 1.

[0260] Table 1

[0261] In the experimental devices shown in Table 1, compound 1 provided in the embodiments of this application and comparative compound 1 provided in the comparative embodiments were used as doped light-emitting materials for the light-emitting layer, respectively. As can be seen from the data in Table 1, compared with comparative embodiments 1 to 6, the organic electroluminescent devices using the organic light-emitting compounds provided in the embodiments of this application all exhibit higher external quantum efficiency and lower driving voltage. Furthermore, the external quantum efficiency significantly exceeds the theoretical limit of 5% for the external quantum efficiency of traditional fluorescent polymers. This indicates the existence of delayed fluorescence emission, suggesting that the organic light-emitting compounds provided in the embodiments of this application possess TADF characteristics and can be used as TADF materials.

[0262] Therefore, the organic light-emitting compound provided in this application uses bisfluorene as its backbone. By connecting electron-donating and electron-accepting groups at different positions on the bisfluorene backbone, the electron-donating and electron-accepting groups can be completely separated yet sufficiently close, thereby enabling space charge transfer between them. This facilitates the organic light-emitting compound to possess TADF characteristics, achieving 100% exciton utilization, and thus obtaining an organic light-emitting compound with superior optical performance and high luminous efficiency. This organic light-emitting compound can be used as a material for the organic layer in organic electroluminescent devices, especially the light-emitting layer, thereby improving the stability and efficiency of organic electroluminescent devices, reducing the driving voltage, and mitigating the efficiency roll-off of organic electroluminescent devices.

[0263] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An organic light-emitting compound, characterized in that, The chemical structure of the organic light-emitting compound is shown in general formula (1): General formula (1), Among them, Y1 and Y2 are independently selected from NR1; Each Z is independently selected from CR1; Each R1 is independently selected from hydrogen atom, deuterium atom, fluorine atom, chlorine atom, bromine atom, iodine atom, cyano group, N(=O)2, N(R2)2, OR2, SR2, C(=O)R2, P(=O)R2, Si(R2)3, and C1-C atoms substituted with one or more deuterium atoms. 20 Alkyl groups, C2-C atoms substituted with one or more deuterium atoms 20 Alkenyl group, C2-C substituted with one or more deuterium atoms 20 Alkyne group, C6-C substituted with one or more deuterium atoms 40 aryl, or C5-C substituted with one or more deuterium atoms. 40 Any of the heteroaryl groups; or, two R1 rings linked together to form a C6-C 18 Aromatic rings or C5-C 18 heterocyclic aromatic rings, the C6-C 18 Aromatic rings or C5-C 18 The heterocyclic aromatic ring is optionally surrounded by one or more C6-C 30 Aryl or C5-C 30 heteroaryl substitution; Each R2 is independently selected from hydrogen, deuterium, fluorine, cyano, or C1-C atoms substituted with one or more deuterium atoms. 20 Alkyl groups, C6-C atoms substituted with one or more deuterium atoms 30 aryl, or C5-C substituted with one or more deuterium atoms. 30 Any one of the heteroaryl groups; R3, R4, and R6 are each independently selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, carbonyl, ester, imide, amide, phosphine oxide substituted with or unsubstituted by one or more R7 groups, and C1-C atoms substituted with or unsubstituted by one or more R7 groups. 40 Alkyl groups, C3-C substituted with one or more R7 groups or unsubstituted groups 60 Cycloalkyl, C1-C substituted with one or more R7s or unsubstituted 40 Alkoxy, C6-C substituted with one or more R7 groups or unsubstituted 60 Aryloxy group, alkyl thio group substituted or unsubstituted with one or more R7 groups, aryl thio group substituted or unsubstituted with one or more R7 groups, alkyl sulfonyl group substituted or unsubstituted with one or more R7 groups, aryl sulfonyl group substituted or unsubstituted with one or more R7 groups, C2-C group substituted or unsubstituted with one or more R7 groups. 40 Alkenyl, silyl group substituted or unsubstituted with one or more R7 groups, boron group substituted or unsubstituted with one or more R7 groups, amino group substituted or unsubstituted with one or more R7 groups, arylphosphin group substituted or unsubstituted with one or more R7 groups, C6-C group substituted or unsubstituted with one or more R7 groups. 60 Aryl group, C5-C substituted with or unsubstituted with one or more R7 groups. 30 Any one of the heteroaryl groups; G is selected from single bonds, C6-C bonds substituted with one or more R7 bonds, or C6-C bonds that are unsubstituted. 30 aryl, C4-C substituted or unsubstituted with one or more R7 groups 30 Any of the heteroaryl groups; A includes an electron-accepting group, wherein A is selected from cyano, sulfone, carbonyl, ester, or C1-C groups substituted with or unsubstituted with one or more R7 groups. 40 Alkyl groups, C3-C substituted with one or more R7 groups or unsubstituted groups 60 Cycloalkyl, C1-C substituted with one or more R7s or unsubstituted 40 Alkyl group, C2-C substituted with one or more R7 groups or unsubstituted 40 Alkenyl, aralkyl substituted or unsubstituted with one or more R7 groups, areneyl substituted or unsubstituted with one or more R7 groups, aramine substituted or unsubstituted with one or more R7 groups, C6-C substituted or unsubstituted with one or more R7 groups. 60 Aryl group, C5-C substituted with or unsubstituted with one or more R7 groups. 30 Any one of the heteroaryl groups; Each R7 is independently selected from deuterium, halogen group, cyano, nitro, hydroxyl, carbonyl, ester, imide, amide, unsubstituted phosphine oxide, and unsubstituted C1-C. 40 Alkyl, unsubstituted C3-C 60 cycloalkyl, unsubstituted C1-C 40 Alkoxy, unsubstituted C6-C 60 Aryloxy group, unsubstituted alkyl thio group, unsubstituted aryl thio group, unsubstituted alkyl sulfonyl group, unsubstituted aryl sulfonyl group, unsubstituted C2-C 40 Alkenyl, unsubstituted silyl, unsubstituted boron, unsubstituted amino, unsubstituted arylphosphinyl, unsubstituted C6-C 60 Aryl.

2. The organic light-emitting compound according to claim 1, characterized in that, In the general formula (1), GA is selected from any of the following groups: In this context, each R5 at each point is independently selected from a hydrogen atom, a cyano group, or a C1-C atom substituted with or unsubstituted with one or more R8 groups. 10 Alkyl groups, C6-C substituted with one or more R8 groups or unsubstituted 24 The aromatic amino group, substituted with one or more R8 groups or unsubstituted C6-C 24 Any one of the following: aryl, aromatic heterol groups substituted or unsubstituted with one or more R8s, pyridine substituted or unsubstituted with one or more R8s, or thiophene substituted or unsubstituted with one or more R8s; Each R8 is independently selected from deuterium, halogen group, cyano, nitro, hydroxyl, carbonyl, ester, imide, amide, unsubstituted phosphine oxide, or unsubstituted C1-C. 40 Alkyl, unsubstituted C3-C 60 cycloalkyl, unsubstituted C1-C 40 Alkoxy, unsubstituted C6-C 60 Aryloxy group, unsubstituted alkyl thio group, unsubstituted aryl thio group, unsubstituted alkyl sulfonyl group, unsubstituted aryl sulfonyl group, unsubstituted C2-C 40 Alkenyl, unsubstituted silyl, unsubstituted boron, unsubstituted amino, unsubstituted arylphosphinyl, unsubstituted C6-C 60 Aryl.

3. The organic light-emitting compound according to claim 1 or 2, characterized in that, The chemical structure of the organic light-emitting compound is shown in Formula I. a ~I d As shown in any of the following:

4. The organic light-emitting compound according to claim 1, characterized in that, The A group further comprises an electron-donating group, and the electron-accepting group and the electron-donating group are conjugately connected. In the general formula (1), GA is selected from any of the following groups: In this context, each R5 at each point is independently selected from a hydrogen atom, a cyano group, or a C1-C atom substituted with or unsubstituted with one or more R8 groups. 10 Alkyl groups, C6-C substituted with one or more R8 groups or unsubstituted 24 The aromatic amino group, substituted with one or more R8 groups or unsubstituted C6-C 24 Any one of the following: aryl, aromatic heterol groups substituted or unsubstituted with one or more R8s, pyridine substituted or unsubstituted with one or more R8s, or thiophene substituted or unsubstituted with one or more R8s; Each R8 is independently selected from deuterium, halogen group, cyano, nitro, hydroxyl, carbonyl, ester, imide, amide, unsubstituted phosphine oxide, or unsubstituted C1-C. 40 Alkyl, unsubstituted C3-C 60 cycloalkyl, unsubstituted C1-C 40 Alkoxy, unsubstituted C6-C 60 Aryloxy group, unsubstituted alkyl thio group, unsubstituted aryl thio group, unsubstituted alkyl sulfonyl group, unsubstituted aryl sulfonyl group, unsubstituted C2-C 40 Alkenyl, unsubstituted silyl, unsubstituted boron, unsubstituted amino, unsubstituted arylphosphinyl, unsubstituted C6-C 60 Aryl.

5. The organic light-emitting compound according to claim 1 or 2, characterized in that, The G is selected from a single bond, or the GA in the general formula (1) is selected from any of the following groups: In this context, each R5 at each point is independently selected from a hydrogen atom, a cyano group, or a C1-C atom substituted with or unsubstituted with one or more R8 groups. 10 Alkyl groups, C6-C substituted with one or more R8 atoms or unsubstituted 24 Aromatic amine group, C6-C substituted with one or more R8 groups or unsubstituted 24 Aryl group, C4-C group substituted with or unsubstituted with one or more R8 groups. 24 Any one of heteroaryl, pyridine substituted or unsubstituted with one or more R8 groups, or thiophene substituted or unsubstituted with one or more R8 groups; Each R8 is independently selected from deuterium, halogen group, cyano, nitro, hydroxyl, carbonyl, ester, imide, amide, unsubstituted phosphine oxide, or unsubstituted C1-C. 40 Alkyl, unsubstituted C3-C 60 cycloalkyl, unsubstituted C1-C 40 Alkoxy, unsubstituted C6-C 60 Aryloxy group, unsubstituted alkyl thio group, unsubstituted aryl thio group, unsubstituted alkyl sulfonyl group, unsubstituted aryl sulfonyl group, unsubstituted C2-C 40 Alkenyl, unsubstituted silyl, unsubstituted boron, unsubstituted amino, unsubstituted arylphosphinyl, unsubstituted C6-C 60 Aryl.

6. Use of an organic light-emitting compound as described in any one of claims 1 to 5, characterized in that, The organic light-emitting compound is used to prepare organic electroluminescent devices.

7. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes: The first and second electrodes are set relative to each other, and An organic layer located between the first electrode and the second electrode; The organic layer includes a light-emitting layer, which includes an organic light-emitting compound as described in any one of claims 1 to 5.

8. The organic electroluminescent device according to claim 7, characterized in that, The light-emitting layer includes a light-emitting material, a sensitizing material, and a host material, wherein at least one of the sensitizing material and the light-emitting material includes the organic light-emitting compound.

9. The organic electroluminescent device according to claim 7 or 8, characterized in that, The organic layer further includes at least one of a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, and an electron injection layer stacked sequentially, wherein the light-emitting layer is located between the electron blocking layer and the hole blocking layer. At least one of the hole injection layer, the hole transport layer, the electron blocking layer, the hole blocking layer, and the electron transport layer comprises an organic light-emitting compound as described in any one of claims 1 to 5.

10. A display screen, characterized in that, It includes a cover plate, a back plate, and an organic electroluminescent device as described in any one of claims 7 to 9, wherein the organic electroluminescent device is located between the back plate and the cover plate.

11. An electronic device, characterized in that, It includes a housing assembly and a display screen as described in claim 10, wherein the display screen is located inside the housing assembly.

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