An organic compound and application thereof, and an organic electroluminescence device comprising the same

Abstract

The application relates to an organic compound, belongs to the technical field of organic light-emitting materials, and simultaneously relates to application of the organic compound and an organic electroluminescent device containing the organic compound. The organic compound has the structure shown in the following formula. The compound provided by the application has good transmission performance and stability, and when the compound is applied to an OLED device, the service life of the device can be effectively improved.

Description

Technical Field

[0001] This invention relates to a compound belonging to the field of organic light-emitting materials technology, and also to the application of this compound and organic electroluminescent devices containing it. Background Technology

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

[0003] The core of an OLED device is a multilayer thin-film structure containing various organic functional materials. Common functionalized organic materials include: hole injection materials, hole transport materials, hole blocking materials, electron injection materials, electron transport materials, electron blocking materials, as well as light-emitting host materials and light-emitting guest materials (dyes). When an electric current is applied, electrons and holes are injected and transported to the light-emitting region, where they recombine, thereby generating excitons and emitting light.

[0004] Common phosphors primarily utilize singlet excitons generated when electrons and holes combine to emit light, and are still widely used in various OLED products. Some metal complexes, such as iridium complexes, can simultaneously utilize both triplet and singlet excitons to emit light; these are called phosphors, and their energy conversion efficiency can be up to four times higher than that of traditional phosphors. Thermally excited delayed fluorescence (TADF) technology promotes the conversion of triplet excitons to singlet excitons, achieving high luminous efficiency without the use of metal complexes, while still effectively utilizing triplet excitons. Thermally excited sensitized fluorescence (TASF) technology uses materials with TADF properties to sensitize the phosphor through energy transfer, also achieving high luminous efficiency.

[0005] Hole transport materials significantly affect the voltage of devices and also regulate the carrier transport balance within the device. Improving the carrier mobility of hole transport materials can enhance luminous efficiency and delay device degradation. Although products using OLED display technology are already commercialized, continuous improvements in device lifespan, efficiency, and other performance aspects are still needed to meet people's demands for higher quality.

[0006] Therefore, there is an urgent need in this field to develop more types of organic materials for use in organic electroluminescent devices, so that the devices have higher luminous efficiency, lower driving voltage and longer lifespan. Summary of the Invention

[0007] To address the shortcomings of existing technologies, one objective of this invention is to provide a compound. This compound exhibits excellent photoelectric properties when applied to OLED devices, and is preferably used as a hole transport material.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] This invention provides a compound having the structure shown in formula (I);

[0010]

[0011] In Formula I, Ar is selected from substituted or unsubstituted aryl groups of C7-C60;

[0012] R1, R2, R3, R4 and R5 are each independently selected from one of hydrogen, deuterium, halogen, cyano, substituted or unsubstituted C1-C30 chain alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl;

[0013] Each of m, n, o, p, and q is independently an integer value from 0 to the maximum allowed value;

[0014] X is selected from O, S, and CR. a R b NR c or SiR d R e ;

[0015] The R a R b R c R d and R e Each is independently selected from one of the following: substituted or unsubstituted C1-C20 chain alkyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, and R a With R b They can be connected in a ring via -O-, -S-, -C(-R)2- or a single bond, R d With R e They can be linked together to form a ring through -O-, -S-, -C(-R)2- or a single bond, wherein R is selected from one of substituted or unsubstituted C1-C20 chain alkyl groups, substituted or unsubstituted C3-C20 cycloalkyl groups;

[0016] When Ar has a substituent group, the substituent group is selected from one or a combination of two of the following: deuterium, halogen, cyano, nitro, hydroxyl, amino, aldehyde, ketone, ester, carbonyl, C1-C30 chain alkyl, C1-C30 alkoxy, C3-C20 cycloalkyl, C3-C20 heterocyclic alkyl, C6-C60 aryl, and C6-C60 fused aryl.

[0017] The above R1, R2, R3, R4, R5, R a R b R c R d R e When R has a substituent group, the substituent group is selected from one or a combination of two of the following: deuterium, halogen, cyano, nitro, hydroxyl, amino, aldehyde, ketone, ester, carbonyl, C1-C30 chain alkyl, C1-C30 alkoxy, C3-C20 cycloalkyl, C3-C20 heterocycloalkyl, C6-C60 aryl, C6-C60 fused-ring aryl, and C3-C60 heteroaryl.

[0018] Preferably, m, n, o, p, and q are all 0.

[0019] Preferably, X is CR a R b NR c or SiR d R e More preferably, X is CR a R b .

[0020] Preferably, Ar is a substituted or unsubstituted C7-C30 aryl group. When Ar has a substituent group, the substituent group is selected from one or a combination of two of the following: deuterium, halogen, cyano, C1-C30 chain alkyl, C1-C30 alkoxy, C3-C20 cycloalkyl, C3-C20 heterocyclic alkyl, C6-C60 aryl, and C6-C60 fused cyclic aryl.

[0021] In this invention, the "substituted or unsubstituted" group can replace one substituent or multiple substituents. When there are multiple substituents, they can be selected from different substituents. In this invention, when the same expression is used, they all have the same meaning, and the selection range of substituents is as shown above and will not be repeated one by one.

[0022] In this specification, the expression Ca-Cb indicates that the group has a number of carbon atoms of ab. Unless otherwise specified, this number of carbon atoms generally does not include the number of carbon atoms of the substituents.

[0023] In this specification, "each independently" means that when there are multiple subjects, they may be the same or different from each other.

[0024] In this invention, unless otherwise specified, the description of chemical elements generally includes the concept of their isotopes. For example, the description of "hydrogen (H)" includes its isotopes. 1 H (protium or H), 2 The concept of H (deuterium or D); carbon (C) includes... 12 C 13 C, etc., will not be elaborated further.

[0025] The heteroatoms in the heteroaryl group of this invention generally refer to atoms or groups of atoms selected from N, O, S, P, Si and Se, preferably from N, O and S.

[0026] Examples of halogens in this specification include fluorine, chlorine, bromine, and iodine.

[0027] In this invention, the substituted or unsubstituted C7-C60 aryl groups include monocyclic aryl groups and fused-ring aryl groups, more preferably C7-C30 aryl groups. A monocyclic aryl group refers to a molecule containing at least one phenyl group. When a molecule contains at least two phenyl groups, the phenyl groups are independent of each other and connected by a single bond, exemplarily such as biphenyl and terphenyl. Specifically, the biphenyl group includes 2-biphenyl, 3-biphenyl, and 4-biphenyl; the terphenyl group includes p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, meta-terphenyl-4-yl, meta-terphenyl-3-yl, and meta-terphenyl-2-yl. A fused-ring aryl group refers to a molecule containing at least two aromatic rings, where the aromatic rings are not independent of each other but share two adjacent carbon atoms fused together. Examples include: naphthyl, anthracene, phenanthryl, indene, fluorenyl, fluoranthyl, triphenylene, pyrene, perylene, etc. Naphthyl, 2-naphthyl, and their derivative groups, etc. The naphthyl includes 1-naphthyl or 2-naphthyl; the anthraceneyl is selected from 1-anthrayl, 2-anthrayl, and 9-anthrayl; the fluorenyl is selected from 1-fluorenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl, and 9-fluorenyl; the pyrene is selected from 1-pyrene, 2-pyrene, and 4-pyrene; the 2-tetraphenyl is selected from 1-2 ... The fluorene derivative group is selected from 9,9-dimethylfluorenyl, 9,9-diethylfluorenyl, 9,9-dipropylfluorenyl, 9,9-dibutylfluorenyl, 9,9-dipentylfluorenyl, 9,9-dihexylfluorenyl, 9,9-diphenylfluorenyl, 9,9-dinaphthylfluorenyl, 9,9'-spirodifluorenyl, and benzo[a]fluorenyl.

[0028] In this invention, the substituted or unsubstituted C3-C30 heteroaryl groups include monocyclic heteroaryl groups and fused-ring heteroaryl groups, more preferably C4-C20 heteroaryl groups, and even more preferably C5-C12 heteroaryl groups. A monocyclic heteroaryl group refers to a molecule containing at least one heteroaryl group. When a molecule contains one heteroaryl group and other groups (such as aryl, heteroaryl, alkyl, etc.), the heteroaryl group and the other groups are independent of each other and connected by a single bond. Examples of monocyclic heteroaryl groups include furanyl, thiophene, pyrrole, and pyridyl. A fused-ring heteroaryl group refers to a molecule containing at least one aromatic heterocycle and an aromatic ring (aromatic heterocycle or aromatic ring), and the two are not independent of each other but share a group consisting of two adjacent atoms fused together. Examples of fused-ring heteroaryl groups include: benzofuranyl, benzothiophenyl, isobenzofuranyl, indolyl, dibenzofuranyl, dibenzothiophenyl, carbazoyl, acridineyl, isobenzofuranyl, isobenzothiophenyl, benzocarbazoyl, azircarbazoyl, phenothiazinyl, phenothiazinyl, 9-phenylcarbazoyl, 9-naphthylcarbazoyl, dibenzocarbazoyl, indolocarbazoyl, etc.

[0029] Unless otherwise specified, the chain alkyl groups mentioned in this invention include straight-chain alkyl groups and branched-chain alkyl groups. Specifically, substituted or unsubstituted C1-C30 chain alkyl groups are preferably substituted or unsubstituted C1-C16 chain alkyl groups, and more preferably substituted or unsubstituted C1-C10 chain alkyl groups. Substituted or unsubstituted C3-C20 cycloalkyl groups are preferably substituted or unsubstituted C3-C10 cycloalkyl groups, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, n-hexyl, n-octyl, isobutyl, tert-butyl, cyclopropyl, cyclobutyl, cyclopentyl, tert-pentyl, cyclohexyl, adamantyl, etc.

[0030] More preferably, the Ar is selected from substituted or unsubstituted groups, wherein the wavy line represents a linking site:

[0031]

[0032] When Ar has a substituent group, the substituent group is selected from one or a combination of two of the following: deuterium, halogen, cyano, C1-C30 chain alkyl, C1-C30 alkoxy, C3-C20 cycloalkyl, C3-C20 heterocyclic alkyl, C6-C60 aryl, and C6-C60 fused aryl.

[0033] More preferably, R1, R2, R3, R4, R5, R a R b R c R d R eR and R are each independently selected from the following substituted or unsubstituted groups: methyl, ethyl, n-propyl, isopropyl, n-butyl, n-hexyl, n-octyl, isobutyl, tert-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, phenyl, naphthyl, anthracene, phenanthryl, indene, fluoranyl, triphenylene, pyrene, perylene, One of the following: 9,9-dimethylfluorenyl, 9,9-diethylfluorenyl, 9,9-dipropylfluorenyl, 9,9-dibutylfluorenyl, 9,9-dipentylfluorenyl, 9,9-dihexylfluorenyl, 9,9-diphenylfluorenyl, 9,9-dinaphthylfluorenyl, spirofluorenyl, benzo[a]fluorenyl, furanyl, thiopheneyl, pyrroleyl, benzo[a]furanyl, benzo[a]thiopheneyl, isobenzo[a]furanyl, indolyl, dibenzo[a]furanyl, dibenzo[a]thiopheneyl, carbazoyl, acridineyl, isobenzo[a]furanyl, isobenzo[a]thiopheneyl, acridineyl, pyridyl, benzo[a]carbazoyl, azacarbazoyl, phenothiazinyl, phenothiazinyl;

[0034] When the above R1, R2, R3, R4, R5, R a R b R c R d R e When R has a substituent group, the substituent group is selected from one or a combination of at least two of the following: deuterium, halogen, C1-C10 chain alkyl, C1-C10 alkoxy, C3-C10 cycloalkyl, C6-C30 aryl, and C3-C30 heteroaryl.

[0035] The core design of this invention lies in the use of a tetraphenylene and a dibenzo5-membered heterocycle to form an amine core structure. First, the two biphenyl groups connected at the 2-position possess significant steric hindrance, preventing excessively dense packing and crystallization of the material. This also suppresses conjugation in the molecular structure, improving the triplet energy level and thus increasing device efficiency and lifespan. Second, the dibenzo5-membered heterocycle structure exhibits good planarity, enhancing carrier transport capabilities. Furthermore, the direct connection of nitrogen atoms to form an aromatic amine facilitates hole injection, further reducing the device's driving voltage. Third, the Ar group in the core structure, selected from C7-C60 aryl groups, connects to the aromatic amine structure. Extensive experimental research has shown that this connection structure ensures the compound's molecular weight remains within a reasonable range, improving the material's thermal stability (Tg) without causing excessively high vapor deposition temperatures.

[0036] When the compounds of the present invention are used to prepare interfaces between layers of OLED devices, they can effectively prevent the formation of excitocomplexes between the functional layers of the OLED device, thereby more effectively improving the efficiency and lifespan of the OLED device.

[0037] Furthermore, the general formula compounds of the present invention are preferably the following specific compounds, but the present invention is not limited to the specific compounds shown below:

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044] As another aspect of the present invention, the application of the compound described above in an organic electroluminescent device is also provided. Specifically, its application as a hole transport layer material in an organic electroluminescent device is preferred. In the present invention, the second hole transport layer also refers to an electron blocking layer, a concept well known to those skilled in the art and will not be elaborated further here.

[0045] More preferably, the compound of the present invention is used as a hole transport layer material and / or an electron blocking layer material in the organic electroluminescent device.

[0046] In addition to organic electroluminescent devices, the compounds of this invention can also be applied to lighting elements, organic thin-film transistors, organic field-effect transistors, organic thin-film solar cells, information tags, electronic artificial skin sheets, sheet-type scanners, or electronic paper.

[0047] As another aspect of the present invention, an organic electroluminescent device is also provided, comprising a first electrode, a second electrode, and an organic layer inserted between the first electrode and the second electrode, characterized in that the organic layer contains a compound of formula (I) as described above, or a compound containing at least one of the structures of P1 to P120 as described above.

[0048] Specifically, one embodiment of the present invention provides an organic electroluminescent device, including a substrate, and a first electrode, a plurality of light-emitting functional layers, and a second electrode sequentially formed on the substrate; the light-emitting functional layers include a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, and an electron transport layer, wherein the hole injection layer is formed on the anode layer, the hole transport layer is formed on the hole injection layer, the cathode layer is formed on the electron transport layer, and the light-emitting layer is located between the hole transport layer and the electron transport layer; wherein the hole transport layer and / or the electron blocking layer material includes at least one compound of Formula I as described above, or a compound containing at least one of the structures shown in P1 to P120 as described above.

[0049] The present invention also discloses a display screen or display panel, wherein the display screen or display panel employs the organic electroluminescent device as described above; preferably, the display screen or display panel is an OLED display.

[0050] The present invention also discloses an electronic device having a display screen or display panel, wherein the display screen or display panel employs an organic electroluminescent device as described above. Detailed Implementation

[0051] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0052] The preferred compounds of this invention can be obtained through common coupling reactions between different halogenated aromatic hydrocarbons and aromatic amines, with representative synthetic routes as follows:

[0053]

[0054] Synthesis example

[0055] Synthesis of compound P1

[0056]

[0057] 20 g of 3-chloro-4-bromoaniline, 12.2 g of phenylboronic acid, and 20 g of potassium carbonate were added to a three-necked flask. 200 mL of toluene, 30 mL of ethanol, and 30 mL of water were added as solvents. After purging with nitrogen, 1 g of tetraphenylphosphine palladium was added, and the mixture was heated to reflux and reacted overnight. After the reaction was complete, an appropriate amount of water was added, and the mixture was extracted with DCM and concentrated. The concentrate was then purified by silica gel column chromatography to obtain P1-1 (18 g) as a colorless oily liquid.

[0058] Under nitrogen protection, P1-1 (18 g), 2-biphenylboronic acid (17.5 g), and potassium carbonate (24 g) were dissolved in dioxane and water. Pd2(dba)3 (1 g) and Sphos (1 g) were added, and the mixture was heated to reflux for 7-8 h under nitrogen protection. After concentration, the mixture was extracted with DCM and purified by silica gel column chromatography to obtain P1-2 (22 g) as a yellowish-white solid.

[0059] In a 500ml three-necked flask, P1-2 (22g), 2-bromo-dimethylfluorene (38g), sodium tert-butoxide (26g), and tris(dibenzylacetone)dipalladium (0.9g) were added. The mixture was then purged with nitrogen three times under vacuum. Tri-tert-butylphosphine ((tert-Bu)3P, 1mol / L, 2ml) was added, and the mixture was heated to reflux and reacted overnight. After the reaction was complete, heating was stopped, and the mixture was filtered hot through diatomaceous earth. The solvent in the filtrate was concentrated. The residue was purified by silica gel column chromatography, and the crude product was washed with ethyl acetate to obtain a white solid, P1 (17g). Theoretical M / Z value: 705.3; Measured value on a ZAB-HS mass spectrometer (Micromass, UK): 706.3 (M+1).

[0060] Synthesis of compound P14

[0061]

[0062] 18 g of 3-chloro-4-bromoaniline, 11 g of phenylboronic acid, and 18 g of potassium carbonate were added to a three-necked flask. 180 mL of toluene, 30 mL of ethanol, and 30 mL of water were added as solvents. After purging with nitrogen, 0.9 g of tetraphenylphosphine palladium was added, and the mixture was heated to reflux and reacted overnight. After the reaction was complete, an appropriate amount of water was added, and the mixture was extracted with DCM and concentrated. The concentrate was then purified by silica gel column chromatography to obtain P14-1 (17 g) as a colorless oily liquid.

[0063] Under nitrogen protection, P14-1 (17 g), 2-biphenylboronic acid (16 g), and potassium carbonate (23 g) were dissolved in dioxane and water. Pd2(dba)3 (1 g) and Sphos (1 g) were added, and the mixture was heated to reflux overnight under nitrogen protection. After concentration, it was extracted with DCM and purified by silica gel column chromatography to obtain P14-2 (20 g) as a yellowish-white solid.

[0064] In a 500 mL single-necked flask, add P14-2 (20 g), 2-bromodimethylfluorene (17 g), sodium tert-butoxide (12 g), tris(dibenzylacetone)dipalladium (0.9 g), and IPr·HCl (0.5 g), along with 200 mL of toluene. The mixture is evacuated under vacuum and purged with nitrogen three times. The reaction is then heated to 90 °C and reacted for 5 h. After the reaction is complete, the reaction is stopped. The mixture is cooled to room temperature, filtered to remove inorganic salts, and the organic phase is concentrated. Methanol is added and the mixture is stirred for 1 h. The mixture is then filtered to obtain a pale yellow powder, P14-3 (23 g).

[0065] P14-3 (23 g), 4-bromobiphenyl (10.3 g), sodium tert-butoxide (8.5 g), and tris(dibenzylacetone)dipalladium (0.9 g) were added to 500 ml of toluene. The mixture was then purged with nitrogen three times under vacuum. Tri-tert-butylphosphine ((tert-Bu)3P, 1 mol / L, 2 ml) was added, and the mixture was heated to reflux and reacted for 8 hours. After the reaction was complete, heating was stopped, and the mixture was filtered through diatomaceous earth while hot. The solvent in the filtrate was concentrated. The residue was purified by silica gel column chromatography, and the crude product was washed with ethyl acetate to obtain a white solid, P14 (15 g).

[0066] Theoretical M / Z value: 665.3; Actual value measured by ZAB-HS mass spectrometer (manufactured by Micromass, UK): 666.3 (M+1).

[0067] Synthesis of compound P21

[0068]

[0069] The synthesis of P21 follows a similar method to that used for P14, except that 4-bromobiphenyl is replaced with 2-(4-bromophenyl)naphthalene to obtain P21.

[0070] Theoretical M / Z value: 715.3; Actual value measured by ZAB-HS mass spectrometer (manufactured by Micromass, UK): 716.3 (M+1).

[0071] Synthesis of compound P24

[0072]

[0073] The synthesis of P24 follows a similar method to that used for P14, except that 4-bromobiphenyl is replaced with 2-(2'-biphenyl)-4-bromobiphenyl to obtain P24.

[0074] Theoretical M / Z value: 817.3; Measured value using ZAB-HS mass spectrometer (manufactured by Micromass, UK): 818.3 (M+1).

[0075] Synthesis of compound P34

[0076]

[0077] The synthesis of P34 follows a similar method to that used for P14, except that 4-bromobiphenyl is replaced with 3-(4'-dimethylfluorenyl)-4-bromobiphenyl to obtain P34.

[0078] Theoretical M / Z value: 857.4; Actual value measured by ZAB-HS mass spectrometer (manufactured by Micromass, UK): 858.4 (M+1).

[0079] Synthesis of compound P45

[0080]

[0081] The synthesis of P45 follows a similar method to that used for P14, except that 2-bromodimethylfluorene is replaced with 1-bromodibenzofuran to obtain P45.

[0082] Theoretical M / Z value: 639.2; Actual value measured by ZAB-HS mass spectrometer (manufactured by Micromass, UK): 640.2 (M+1).

[0083] Synthesis of compound P57

[0084]

[0085] The synthesis of P57 follows a similar method to that used for P14, except that 4-bromobiphenyl is replaced with 4-bromo-4'-tert-butylbiphenyl to obtain P57.

[0086] Theoretical M / Z value: 721.3; Actual value measured by ZAB-HS mass spectrometer (manufactured by Micromass, UK): 722.3 (M+1).

[0087] Synthesis of compound P82

[0088]

[0089] The synthesis of P14 was similar to that of P82, except that 4-bromobiphenyl was replaced with 9-(4-bromophenyl)9'-phenyl-fluorene to obtain P82.

[0090] Theoretical M / Z value: 829.3; Actual value measured by ZAB-HS mass spectrometer (manufactured by Micromass, UK): 830.3 (M+1).

[0091] Synthesis of compound P103

[0092]

[0093] The synthesis of P103 was performed using a method similar to that used for P1, except that 2-biphenylboronic acid was replaced with 4-tert-butyl-2-biphenylboronic acid and 2-bromo-dimethylfluorene was replaced with 3-bromo-dimethylfluorene, thus yielding P103.

[0094] Theoretical M / Z value: 761.4; Actual value measured by ZAB-HS mass spectrometer (manufactured by Micromass, UK): 762.4 (M+1).

[0095] Synthesis of compound P111

[0096]

[0097] The synthesis of P111 was performed using a similar method to that used for P14, except that 4-bromobiphenyl was replaced with 4-deuterated tert-butyl-4'-bromobiphenyl to obtain P111.

[0098] Theoretical M / Z value: 682.3; Actual value measured by ZAB-HS mass spectrometer (manufactured by Micromass, UK): 683.3 (M+1).

[0099] Synthesis of compound P119

[0100]

[0101] The synthesis of P119 follows a similar method to that used for P14, except that 2-bromodimethylfluorene is replaced with 3-bromodimethylfluorene and 4-bromobiphenyl is replaced with 2-bromo-1,1'-naphthyl, thus yielding P119.

[0102] Theoretical M / Z value: 765.3; Actual value measured by ZAB-HS mass spectrometer (manufactured by Micromass, UK): 766.3 (M+1).

[0103] Synthesis of compound compare6

[0104]

[0105] The method for synthesizing P14 is similar to that for synthesizing compare6, except that 2-bromodimethylfluorene is replaced with 2-(4-bromophenyl)-9,9-dimethylfluorene to obtain compare6.

[0106] Theoretical M / Z value: 741.3; Actual value measured by ZAB-HS mass spectrometer (manufactured by Micromass, UK): 742.3 (M+1).

[0107] This invention provides exemplary methods for synthesizing the above-mentioned compounds. For compounds in the following examples that do not have specific synthesis methods, they are also prepared by similar methods, requiring only the replacement of raw materials. These methods will not be elaborated here, or those skilled in the art can prepare them using other methods in the prior art.

[0108] Device Examples

[0109] An OLED includes a first electrode and a second electrode, and an organic material layer located between the electrodes. This organic material layer can be further divided into multiple regions. For example, the organic material layer may include a hole transport region, a light-emitting layer, and an electron transport region.

[0110] In specific embodiments, a substrate can be used below the first electrode or above the second electrode. The substrate is typically made of glass or polymer material with excellent mechanical strength, thermal stability, water resistance, and transparency. Furthermore, thin-film transistors (TFTs) can also be incorporated into the substrate used for displays.

[0111] The first electrode can be formed by sputtering or depositing the material to be used as the first electrode on a substrate. When the first electrode is used as the anode, it can be a transparent conductive oxide material such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), zinc oxide (ZnO), or any combination thereof. When the first electrode is used as the cathode, it can be a metal or alloy such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), ytterbium (Yb), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag), or any combination thereof.

[0112] Organic functional layers can be formed on electrodes using methods such as vacuum thermal evaporation, spin coating, and printing. The compounds used as organic material layers can be small organic molecules, large organic molecules, polymers, and combinations thereof.

[0113] The hole transport region is located between the anode and the emissive layer. The hole transport region can be a single-layer hole transport layer (HTL), including single-layer hole transport layers containing only one compound and single-layer hole transport layers containing multiple compounds. Alternatively, the hole transport region can be a multilayer structure including at least one of a hole injection layer (HIL), a hole transport layer (HTL), and an electron blocking layer (EBL); wherein the HIL is located between the anode and the HTL, and the EBL is located between the HTL and the emissive layer.

[0114] The material for the hole transport region may be selected from, but is not limited to, phthalocyanine derivatives such as CuPc, conductive polymers or polymers containing conductive dopants such as polyphenylene ethylene, polyaniline / dodecylbenzenesulfonic acid (Pani / DBSA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate) (PEDOT / PSS), polyaniline / camphorsulfonic acid (Pani / CSA), polyaniline / poly(4-styrenesulfonate) (Pani / PSS), aromatic amine derivatives, wherein the aromatic amine derivatives include compounds shown below HT-1 to HT-51; or any combination thereof.

[0115]

[0116]

[0117]

[0118] The hole injection layer is located between the anode and the hole transport layer. The hole injection layer can be a single compound material or a combination of multiple compounds. For example, the hole injection layer can be one or more compounds of HT-1 to HT-51 described above, or one or more compounds of HI-1 to HI-3 described below; it can also be one or more compounds of HT-1 to HT-51 doped with one or more compounds of HI-1 to HI-3 described below.

[0119]

[0120] The emissive layer includes luminescent dyes (i.e., dopants) that can emit different wavelengths of light, and may also include a host material. The emissive layer can be a monochromatic emissive layer emitting a single color such as red, green, or blue. Multiple monochromatic emissive layers of different colors can be arranged in a planar pattern according to pixel design, or they can be stacked together to form a colored emissive layer. When different colored emissive layers are stacked together, they can be separated from each other or connected to each other. The emissive layer can also be a single colored emissive layer that can simultaneously emit different colors such as red, green, and blue.

[0121] Depending on the technology used, the light-emitting layer material can be various, including fluorescent electroluminescent materials, phosphorescent electroluminescent materials, and thermally activated delayed fluorescence materials. An OLED device can employ a single light-emitting technology or a combination of different technologies. These different light-emitting materials, categorized by technology, can emit light of the same color or different colors.

[0122] In one aspect of the invention, the light-emitting layer employs fluorescent electroluminescence technology. The fluorescent host material of the light-emitting layer may be selected from, but is not limited to, one or more combinations of BFH-1 to BFH-17 listed below.

[0123]

[0124] In one aspect of the invention, the light-emitting layer employs fluorescent electroluminescence technology. The fluorescent dopant of the light-emitting layer may be selected from, but not limited to, one or more combinations of BFD-1 to BFD-24 listed below.

[0125]

[0126]

[0127] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The main material of the light-emitting layer is selected from, but not limited to, one or more combinations of pH-1 to pH-85.

[0128]

[0129]

[0130]

[0131]

[0132] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The phosphorescent dopant of the light-emitting layer may be selected from, but not limited to, one or more combinations of GPD-1 to GPD-47 listed below.

[0133]

[0134]

[0135]

[0136] Where D represents deuterium.

[0137] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The phosphorescent dopant of the light-emitting layer may be selected from, but not limited to, one or more combinations of RPD-1 to RPD-28 listed below.

[0138]

[0139]

[0140] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The phosphorescent dopant of the light-emitting layer may be selected from, but not limited to, one or more combinations of YPD-1 to YPD-11 listed below.

[0141]

[0142] The OLED organic material layer may also include an electron transport region between the light-emitting layer and the cathode. The electron transport region can be a single-layer electron transport layer (ETL), including single-layer electron transport layers containing only one compound and single-layer electron transport layers containing multiple compounds. Alternatively, the electron transport region can be a multilayer structure including at least one of an electron injection layer (EIL), an electron transport layer (ETL), and a hole blocking layer (HBL).

[0143] In one aspect of the present invention, the electron transport layer material may be selected from, but not limited to, one or more combinations of ET-1 to ET-73 listed below.

[0144]

[0145]

[0146]

[0147] The device may also include an electron injection layer located between the electron transport layer and the cathode. The electron injection layer material includes, but is not limited to, one or more combinations of the following: LiQ, LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Yb, Li or Ca.

[0148] The cathode is a mixture of magnesium and silver, LiF / Al, ITO and other metals, metal mixtures and oxides.

[0149] Example 1

[0150] The fabrication process of the organic electroluminescent device in this embodiment is as follows:

[0151] The glass plate coated with an ITO transparent conductive layer (as the anode) was ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in an acetone:ethanol mixed solvent, baked in a clean environment until all moisture was removed, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam.

[0152] The glass substrate with the anode was placed in a vacuum chamber and evacuated to less than 1×10-5 Pa. A 10 nm HTL-4:HI-3 (97 / 3, w / w) mixture was vacuum thermally deposited on the anode film in sequence as a hole injection layer.

[0153] The 60nm compound HT-4 is used as the first hole transport layer;

[0154] The 5nm compound P1 of this invention is used as the second hole transport layer (also known as the electron blocking layer);

[0155] A 40nm PH-34:RPD-10 (100:3, w / w) binary mixture was used as the emitting layer; a 5nm ET-23 was used as the hole blocking layer; a 25nm ET-69:ET-57 (50 / 50, w / w) mixture was used as the electron transport layer; a 1nm LiF was used as the electron injection layer; and a 150nm aluminum electrode was used as the cathode. The total evaporation rate of all organic layers and LiF was controlled at 0.1nm / s, and the evaporation rate of the metal electrode was controlled at 1nm / s.

[0156] The fabrication process of the organic electroluminescent devices provided in Examples 2-11 and Comparative Examples 1-6 is the same as that in Example 1, except that the second hole transport layer material compound P1 is replaced with the compounds of the present invention shown in Table 1 and the prior art compounds used for comparison.

[0157] The structures of the prior art compounds used in the second hole transport layer materials of Comparative Examples 1-6 are shown below:

[0158]

[0159] For details of compare1, see patent application CN109485577A; for details of compare2, see patent application KR1020180104911A; for details of compare3, see patent application CN107210382A; and for details of compare4 and compare5, see patent application CN107408636A.

[0160] The organic electroluminescent devices prepared by the above process were subjected to the following performance measurements:

[0161] Under the same brightness, the driving voltage and current efficiency of the organic electroluminescent devices prepared in the examples and comparative examples were measured using a digital source meter (Keithley 2400) and a luminance meter (ST-86LA type luminance meter, Beijing Normal University Optoelectronic Instrument Factory). Specifically, the voltage and efficiency were measured at 3000 cd / m². 2 The measured lifetime (LT97) was 60 mA / cm. 2 The time it takes for the brightness to decay to 97% of its initial brightness under constant current. The obtained data are summarized in the table below; test results are shown in Table 1.

[0162] Table 1:

[0163] Comparative Example 1 compare1 4.98 15.7 89 Comparative Example 2 compare2 5.07 15.2 84 Comparative Example 3 compare3 5.23 14.9 90 Comparative Example 4 compare4 4.88 16.1 93 Comparative Example 5 Compare5 4.96 15.8 87 Comparative Example 6 compare6 4.86 15.6 86 Example 1 P1 3.92 18.9 100 Example 2 P14 4.00 19.0 98 Example 3 P21 4.08 18.8 103 Example 4 P24 4.12 19.4 102 Example 5 P34 3.99 19.5 106 Example 6 P45 4.09 18.2 101 Example 7 P57 3.95 19.8 97 Example 8 P82 4.04 18.7 104 Example 9 P103 4.01 19.3 103 Example 10 P111 4.02 19.1 107 Example 11 P119 4.06 19.7 100

[0164] The data shows that the novel organic material provided by this invention can produce superior performance through the combination of specific substituents. When used in organic electroluminescent devices, it can more effectively improve current efficiency, reduce driving voltage, and extend device lifespan, enabling the device to achieve a driving voltage as low as 4.52-4.70V, a current efficiency of 18.2-19.8cd / A, and a lifespan of 97-106h, making it a high-performance secondary hole transport material.

[0165] The compounds of this invention use C7-C60 aryl groups to connect N, which, compared to compound compare1 which uses phenyl groups to directly connect to aromatic amines, results in better molecular planarity and steric hindrance, preventing excessive molecular packing and crystallization that could affect stability. Furthermore, it facilitates hole transport, further influencing the electron-hole balance in the device. Therefore, the compounds of this invention have lower driving voltages and higher efficiency and lifetime. In the general formula of this invention, Ar does not use heteroaryl groups. In contrast, in compound compare2 of Comparative Example 2, the dibenzofuran is connected to the N of the aromatic amine via a phenyl group, and in compound compare6 of Comparative Example 6, the dimethylfluorene group is connected to the aromatic amine via a phenyl group. Both of these weaken the hole-trapping ability of the N in the aromatic amine, leading to poorer implantation and inferior device performance compared to the compounds of this invention. In the compounds of this invention, the dibenzo-5-membered heterocyclic group itself has a certain electron-donating effect, which directly connects to the N in the aromatic amine to enhance the hole injection capability. Moreover, the dibenzo-5-membered ring has better structural planarity. Compared with the compound in Comparative Example 3 which uses a biphenyl structure, it has better stability in the excited state, which is more conducive to improving efficiency and lifetime. Device data results also show that the compound of this invention has a lower driving voltage and higher efficiency and lifetime.

[0166] The biphenyl structure used in the core structure of the compound of the present invention is different from the biphenyl in Comparative Example 4 in that the N-position is different, and it is also different from the ortho-terphenyl used in Comparative Example 5. In the present invention, the N-position is connected to the 4-position of the biphenyl, and the ortho-biphenyl is connected to the 2-position of the biphenyl. The structure has greater twist and exhibits greater steric hindrance, which can not only reduce the energy loss caused by molecular vibration in the excited state, but also improve the LUMO energy level of the material, making it easier for exciton recombination to occur in the light-emitting layer. This is more conducive to reducing voltage, improving efficiency and lifetime. As can also be seen from the device data results, the compound of the present invention performs better than compare4 and compare5.

[0167] This invention illustrates the compounds of the present invention and their application in OLED devices through the above embodiments. However, the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention. It should be understood that, guided by the concept of the present invention, those skilled in the art can make various modifications and improvements, and the appended claims summarize the scope of the present invention.

Claims

1. An organic compound having the structure shown in formula (I): Equation (I) In Formula I, Ar is selected from substituted or unsubstituted groups, and when Ar has a substituted group, the substituted group is selected from deuterium and C1-C30 chain alkyl groups, where the wavy line represents the linkage site: ； R1, R2, R3, R4 and R5 are each independently selected from one of hydrogen, deuterium, and C1-C30 chain alkyl groups; m, n, o, p, and q are each independently 0 or 1; X is selected from CR a R b ; R a R b Each is independently selected from C1-C20 chain alkyl groups.

2. The organic compound according to claim 1, wherein in formula (I), m, n, o, p and q are all 0.

3. The organic compound according to claim 1, wherein in formula (I), R1, R2, R3, R4, and R5 are each independently selected from one of the following groups: methyl, ethyl, n-propyl, isopropyl, n-butyl, n-hexyl, n-octyl, isobutyl, and tert-butyl.

4. An organic compound selected from any of the structures shown below: 。 5. The application of the organic compound of any one of claims 1-4 as a functional material in an organic electronic device, wherein the organic electronic device is selected from organic electroluminescent devices, lighting elements, organic thin-film transistors, organic field-effect transistors, organic thin-film solar cells, information tags, electronic artificial skin sheets, sheet-type scanners, or electronic paper; The organic compound is used as a hole transport layer material and / or an electron blocking layer material in organic electroluminescent devices.

6. An organic electroluminescent device, comprising a first electrode, a second electrode, and one or more light-emitting functional layers inserted between the first electrode and the second electrode, wherein the light-emitting functional layer contains an organic compound as described in any one of claims 1-4.

7. An organic electroluminescent device, comprising a first electrode, a second electrode, and a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, and an electron transport layer inserted between the first electrode and the second electrode, wherein the electron blocking layer and / or the hole transport layer contains an organic compound as described in any one of claims 1-4.

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