A polycyclic aromatic compound and its preparation method and application

Abstract

The present invention discloses a polycyclic aromatic compound, a preparation method and an application thereof. The structure of the polycyclic aromatic compound is shown below: #imgabs0# The polycyclic aromatic compound with a novel structure obtained by the present invention, when used in an organic electroluminescent device, has a narrower half-peak width, improved color purity, and at the same time improves the efficiency of the device and increases the service life.

Description

Technical Field

[0001] The present invention relates to the field of organic photoelectric materials, and more particularly to a polycyclic aromatic compound and a preparation method and application thereof. Background Art

[0002] Organic Light Emitting Diode (OLED) is a new and promising display technology that has gradually entered people's field of vision. OLED is an electroluminescent device formed by a multi-layer organic thin film structure.

[0003] The core organic light-emitting materials of OLED display technology achieve a full color gamut by mixing red, green, and blue light-emitting materials. The development of new light-emitting materials is the driving force behind the continuous advancement of electroluminescent technology and a research hotspot in the organic electroluminescent industry. The low efficiency and short lifespan of blue light-emitting materials have greatly limited the use of OLED displays. Therefore, the development of new blue organic electroluminescent materials aims to achieve high luminous efficiency and a longer lifespan for devices. Furthermore, blue light-emitting materials with narrow half-width (FWHM) and high color purity are key priorities in this development.

[0004] At present, the introduction of heterogeneous elements such as boron, nitrogen, oxygen, and phosphorus into large conjugated polycyclic aromatic hydrocarbons (PAHs) can greatly improve the luminescence properties of PAHs. Based on polycyclic aromatic hydrocarbons such as boron, nitrogen, and oxygen, the opposite vibrations of boron and heteroatoms such as nitrogen and oxygen (MR effect) are fully utilized to construct polycyclic aromatic compounds formed by condensing multiple aromatic rings with boron atoms and heteroatoms such as nitrogen and oxygen, that is, to prepare a special rigid material system containing boron atoms and nitrogen and oxygen heteroatoms. Not only does it meet the requirements of high radiation transition rate and narrow half-peak width, but its material also has high color purity. However, the luminous intensity of the film is reduced due to the stacking between molecules, which often leads to unsatisfactory performance in terms of device life and luminous efficiency. In addition, the emission peak position and half-peak width seriously affect the color purity of blue light emission. Therefore, obtaining high-luminescence, high-efficiency, and high-color purity materials has always been a problem to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the present invention provides a polycyclic aromatic compound and its preparation method and application. The polycyclic aromatic compound with a novel structure provided by the present invention, after being used in an organic electroluminescent device, has a narrower half-peak width, improved color purity, and at the same time improves the efficiency of the device and increases the service life.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A polycyclic aromatic compound, the structure of which is shown in general formula II:

[0008]

[0009] Wherein, in the general formula II,

[0010] Z are independently selected from C(R3) or N, and at least one is C(R3);

[0011] n1 and n2 are integers from 0 to 4;

[0012] R1-R3 are each independently selected from hydrogen, deuterium, halogen, cyano, trifluoromethyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C6-C50 aryl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C2-C50 heteroaryl, or substituted or unsubstituted C1-C30 alkoxy; wherein the heteroatom is selected from oxygen, nitrogen, and sulfur; at least one of R3 is fluoro, trifluoromethyl, substituted with fluoro, or substituted with trifluoromethyl;

[0013] Furthermore, Z1 in the general formula II is selected from hydrogen, deuterium, halogen, cyano, trifluoromethyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C2-C30 heteroaryl, and its heteroatom is selected from oxygen, nitrogen, sulfur, and substituted or unsubstituted C1-C30 alkoxy.

[0014] A polycyclic aromatic compound, characterized in that its structure is as shown in general formula I:

[0015]

[0016] Preferably, in the general formula I,

[0017] Z are independently selected from C(R3) or N, and at least one is C(R3);

[0018] n1 and n2 are integers from 0 to 4;

[0019] R1-R3 are each independently selected from hydrogen, deuterium, halogen, cyano, trifluoromethyl, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C6-C50 aryl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C2-C50 heteroaryl, or substituted or unsubstituted C1-C30 alkoxy; wherein the heteroatom is selected from oxygen, nitrogen, and sulfur; at least one of R3 is fluoro, trifluoromethyl, substituted with fluoro, or substituted with trifluoromethyl;

[0020] Preferably, the general formula I and general formula II include the following structures:

[0021]

[0022] In the chemical formula I-1 and chemical formula I-2, R 11 Each is independently selected from methyl, ethyl, isopropyl, and tert-butyl;

[0023] In the chemical formula II-1, chemical formula II-2, and chemical formula II-3, m is an integer of 0-5, R 11 are independently selected from methyl, ethyl, isopropyl, and tert-butyl;

[0024] Wherein, R4 is independently selected from hydrogen, deuterium, halogen, substituted or unsubstituted C1~C30 alkyl, substituted or unsubstituted C6~C18 aryl, substituted or unsubstituted C3~C18 heteroaryl; when m≥2, and R4 is adjacently substituted, two adjacent R4 substituents can be selected from substituted or unsubstituted C5~C12 aliphatic ring, substituted or unsubstituted C6~C18 aromatic ring, substituted or unsubstituted C3~C12 heteroaromatic ring.

[0025] Preferably, R1 to R4 are the same as or different from each other and are independently selected from hydrogen, deuterium, halogen, cyano, trifluoromethyl, substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C30 heteroaryl, substituted or unsubstituted C1 to C30 alkoxy; the heteroatoms are selected from oxygen, nitrogen, and sulfur; at least one of R3 is fluoro, trifluoromethyl, substituted by fluoro, or substituted by trifluoromethyl.

[0026] Preferably, Z1 is selected from hydrogen, deuterium, halogen, cyano, trifluoromethyl, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C6-C20 aryl, substituted or unsubstituted C2-C20 heteroaryl, wherein the heteroatom is selected from oxygen, nitrogen, sulfur, and substituted or unsubstituted C1-C10 alkoxy.

[0027] Preferably, R1 to R4 are each independently selected from hydrogen, deuterium, halogen, cyano, trifluoromethyl, methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, pentyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, 1-methylhexyl, phenyl, naphthyl, 1,1,4,4-tetramethyl-1,2,3,4-tetrahydronaphthalene, anthracenyl, phenanthrenyl, thienyl, furyl, pyrrolyl, benzothienyl, benzofuranyl, pyridyl, quinolinyl, indolyl, cyclopentane, cyclohexane, adamantane, and fluorine-substituted C1-C10 alkoxy.

[0028] R3 independently connects with adjacent R3 substituents to form a monocyclic ring, a C3-C20 aliphatic ring or a C6-C20 aromatic ring; the carbon atoms in the monocyclic ring, the C3-C20 aliphatic ring or the C6-C20 aromatic ring can be replaced by nitrogen, oxygen and sulfur.

[0029] In further embodiments, Z1 is preferably hydrogen, deuterium, halogen, cyano, trifluoromethyl, methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, pentyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1- methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, 1-methylhexyl, substituted or unsubstituted phenyl, substituted or unsubstituted 1,1,4,4-tetramethyl-1,2,3,4-tetrahydronaphthalene, substituted or unsubstituted naphthyl, anthracenyl, phenanthrenyl, substituted or unsubstituted pyridine, substituted or unsubstituted quinoline, substituted or unsubstituted thienyl, substituted or unsubstituted furanyl, substituted or unsubstituted pyrrolyl, substituted or unsubstituted benzothienyl, substituted or unsubstituted benzofuranyl, substituted or unsubstituted indolyl, substituted or unsubstituted cyclopentane, substituted or unsubstituted cyclohexane.

[0030] Preferably, the Z1 comprises the following structure:

[0031]

[0032] wherein * is a connecting bond, n4 is an integer from 0 to 5, n5 is an integer from 0 to 7, and R5-R8 are each independently selected from hydrogen, deuterium, halogen, cyano, trifluoromethyl, methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, pentyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, 1-methylhexyl, substituted or unsubstituted phenyl, substituted or unsubstituted 1,1,4,4-tetramethyl-1,2,3,4-tetrahydronaphthalene, substituted or unsubstituted naphthyl, substituted or unsubstituted pyridine, substituted or unsubstituted quinoline, substituted or unsubstituted cyclopentane, and substituted or unsubstituted cyclohexane.

[0033] Preferably, the general formula I and general formula II specifically include the following structures:

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040] Among them, Et is ethyl, t-Bu is tert-butyl, t-Am is tert-amyl, and i-Pr is isopropyl.

[0041] A method for preparing a polycyclic aromatic compound, characterized in that the synthesis paths of Chemical Formula I and Chemical Formula II are as follows:

[0042]

[0043] The specific steps include:

[0044] (1) Under nitrogen protection, raw material A (1.0 eq), raw material B (1.0 eq), sodium tert-butoxide (2.00 eq), tris(dibenzylideneacetone)dipalladium (Pd2(dba)3) (0.01 eq), and tri-tert-butylphosphine (P(t-Bu)3) (0.05 eq) were dissolved in dry toluene solution, heated to 90-120°C with stirring, and refluxed for 10-12 h; the reaction was monitored by TCL dot plate. After the reaction was completed, the temperature was lowered to room temperature, water was added to quench the reaction, the organic phase was separated and collected, and filtered using diatomaceous earth to remove salt and catalyst; the collected organic phase was dried using anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator; the intermediate A was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether;

[0045] (2) Under nitrogen protection, raw material D (1.0 eq), raw material C (1.0 eq), sodium tert-butoxide (2.00 eq), tris(dibenzylideneacetone)dipalladium (0.01 eq), and tri-tert-butylphosphine (0.05 eq) were dissolved in a dry toluene solution, and the temperature was raised and refluxed under stirring; the reaction was monitored by TCL dot plate. After the reaction was completed, the temperature was lowered to room temperature, water was added to quench the reaction, the organic phase was separated and collected, and filtered using diatomaceous earth to remove salt and catalyst; the collected organic phase was dried using anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator; the intermediate B was obtained by purification by column chromatography using a mixed solution of dichloromethane and petroleum ether;

[0046] (3) Under nitrogen protection, raw material E (1.0 eq), raw material F (1.0 eq), tetrakistriphenylphosphine palladium (Pd(PPh3)4) (0.01 eq), and potassium carbonate (2.0 eq) were dissolved in toluene / ethanol / water, and the temperature was raised to 80-110°C with stirring, and the reaction was carried out for 8-12 hours; the reaction was monitored by TCL plate. After the reaction was completed, the temperature was lowered to room temperature, the organic phase was retained, and filtered using diatomaceous earth to remove salt and catalyst; after the organic phases were combined, they were dried using anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The intermediate F was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether;

[0047] (4) Under nitrogen protection, intermediate C (1.0 eq), raw material C (1.0 eq), sodium tert-butoxide (2.00 eq), tris(dibenzylideneacetone)dipalladium (0.01 eq), and tri-tert-butylphosphine (0.05 eq) were dissolved in dry toluene solution, heated to 90-120°C with stirring, and refluxed for 8-12 h; the reaction was monitored by TCL dot plate. After the reaction was completed, the temperature was lowered to room temperature, water was added to quench the reaction, the organic phase was separated and collected, and filtered using diatomaceous earth to remove salt and catalyst; the collected organic phase was dried using anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator; intermediate D was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether;

[0048] The synthesis path of the chemical formula I is as follows:

[0049] Under nitrogen protection, raw material G (1.0 eq), raw material H (1.0 eq), sodium tert-butoxide (2.00 eq), tris(dibenzylideneacetone)dipalladium (0.01 eq), and tri-tert-butylphosphine (0.05 eq) were dissolved in dry toluene solution, heated to 80-120°C under stirring, and refluxed for 8-12 hours; the reaction was monitored by TCL dot plate. After the reaction was completed, the temperature was lowered to room temperature, water was added to quench the reaction, the organic phase was separated and collected, and filtered using diatomaceous earth to remove salt and catalyst; the collected organic phase was dried using anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator; dissolved in methanol, recrystallized, filtered, the filter cake was rinsed with methanol several times, and placed in a 60°C oven to dry for 6-7 hours to obtain intermediate E;

[0050] Under nitrogen protection, intermediate E (1.0 eq), intermediate A (1.0 eq), sodium tert-butoxide (2.00 eq), tris(dibenzylideneacetone)dipalladium (0.01 eq), and tri-tert-butylphosphine (0.05 eq) were dissolved in dry toluene solution, heated to 90-120°C with stirring, and refluxed for 8-12 hours; the reaction was monitored by TCL dot plate. After the reaction was completed, the temperature was lowered to room temperature, water was added to quench the reaction, the organic phase was separated and collected, and filtered using diatomaceous earth to remove salt and catalyst; the collected organic phase was dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator; dissolved in methanol, recrystallized, filtered, the filter cake was rinsed with methanol several times, and dried in a 60°C oven for 6-7 hours to obtain intermediate F;

[0051] Under nitrogen protection, intermediate F (1.0 eq), intermediate B (1.0 eq), sodium tert-butoxide (2.00 eq), tris(dibenzylideneacetone)dipalladium (0.01 eq), and tri-tert-butylphosphine (0.05 eq) were dissolved in dry toluene solution, heated to 90-120°C with stirring, and refluxed for 8-12 h; the reaction was monitored by TCL dot plate. After the reaction was completed, the temperature was lowered to room temperature, water was added to quench the reaction, the organic phase was separated and collected, and filtered using diatomaceous earth to remove salt and catalyst; the collected organic phase was dried using anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator; dissolved in methanol, recrystallized, filtered, the filter cake was rinsed with methanol several times, and dried in a 60°C oven for 6-7 h to obtain intermediate G;

[0052] Under a nitrogen atmosphere, intermediate G (1.0 eq) was dissolved in o-dichlorobenzene solution and placed in a reaction flask. The nitrogen was replaced, and boron triiodide (2.0 eq-3.0 eq) was added dropwise. The temperature was slowly raised to 120-150° C. and stirring was continued overnight. The reaction was monitored by TCL. After the reaction was completed, the mixture was cooled to room temperature and DIPEA was added to adjust the mixture to neutral. The mixture was extracted with water, and the organic phase was collected and removed by vortexing. The mixture was purified by column chromatography using a mixture of dichloromethane and petroleum ether (V:V = 1:4) to obtain the compound of formula I.

[0053] The synthesis path of Chemical Formula II is as follows:

[0054] Under nitrogen protection, intermediate E (1.0 eq), intermediate D (1.0 eq), sodium tert-butoxide (2.00 eq), tris(dibenzylideneacetone)dipalladium (0.01 eq), and tri-tert-butylphosphine (0.05 eq) were dissolved in dry toluene solution, heated to 90-120°C with stirring, and refluxed for 8-12 hours; the reaction was monitored by TCL dot plate. After the reaction was completed, the temperature was lowered to room temperature, water was added to quench the reaction, the organic phase was separated and collected, and filtered through diatomaceous earth to remove salt and catalyst; the collected organic phase was dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator; dissolved in methanol, recrystallized, filtered, the filter cake was rinsed with methanol multiple times, and dried in a 60°C oven for 6-7 hours to obtain intermediate H;

[0055] Under nitrogen protection, intermediate H (1.0 eq), intermediate B (1.0 eq), sodium tert-butoxide (2.00 eq), tris(dibenzylideneacetone)dipalladium (0.01 eq), and tri-tert-butylphosphine (0.05 eq) were dissolved in dry toluene solution, heated to 90-120°C with stirring, and refluxed for 6-12 hours; the reaction was monitored by TCL dot plate. After the reaction was completed, the temperature was lowered to room temperature, water was added to quench the reaction, the organic phase was separated and collected, and filtered using diatomaceous earth to remove salt and catalyst; the collected organic phase was dried using anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator; dissolved in methanol, recrystallized, filtered, the filter cake was rinsed with methanol multiple times, and dried in a 60°C oven for 6-7 hours to obtain intermediate J;

[0056] Under a nitrogen atmosphere, intermediate J (1.0 eq) was dissolved in o-dichlorobenzene solution and placed in a reaction flask. The nitrogen was replaced, and boron triiodide (2.0 eq-3.0 eq) was added dropwise. The temperature was slowly raised to 120-150° C. and stirring was continued overnight. The reaction was monitored by TCL. After the reaction was completed, it was cooled to room temperature and DIPEA was added to adjust to neutrality. Water was added for extraction, and the organic phase was collected and removed by vortexing. The organic phase was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V = 1:4) to obtain Chemical Formula II.

[0057] Preferably, in step (2), the temperature is raised to 90-120° C., and the reaction is refluxed for 8-12 hours.

[0058] Preferably, in the synthesis pathway of Chemical Formula I, the molar ratio of raw material A to raw material B is 1:1-1.2, and the reaction temperature is 80-150°C; the molar ratio of raw material C to raw material D is 1:1-1.2, and the reaction temperature is 80-150°C; the molar ratio of raw material E to raw material F is 1:1-1.2, and the reaction temperature is 80-130°C; the molar ratio of intermediate C to raw material C is 1:1-1.2, and the reaction temperature is 80-150°C; the molar ratio of raw material G to raw material H is 1:1-1.2, and the reaction temperature is 80-150°C; the molar ratio of intermediate E to intermediate A is 1:1-1.2, and the reaction temperature is 80-150°C; the molar ratio of intermediate F to intermediate B is 1:1-1.2, and the reaction temperature is 80-150°C; the molar ratio of intermediate G to boron tribromide (or boron triiodide) is 1:2-16.

[0059] Preferably, in the synthetic route of chemical formula II, the molar ratio of intermediate E to intermediate D is 1:1-1.2, and the reaction temperature is 80-150°C; the molar ratio of intermediate E to intermediate D is 1:1-1.2, and the reaction temperature is 80-150°C; the molar ratio of intermediate J to boron tribromide (or boron triiodide) is 1:2-16.

[0060] An organic electroluminescent device comprises an anode, a cathode, and an organic layer disposed between the anode and the cathode, wherein the organic layer comprises a light-emitting layer, and a raw material of the light-emitting layer comprises a doping material and the polycyclic aromatic compound according to any one of claims 1 to 4.

[0061] It can be seen from the above technical solutions that compared with the prior art, the present invention has the following beneficial effects:

[0062] The polycyclic aromatic compounds of the present invention, characterized by a large conjugated core structure, ensure strong oscillator strength, enabling the production of highly efficient light-emitting devices. The introduction of heterogeneous elements such as boron, oxygen, nitrogen, and sulfur into the polycyclic aromatic compounds imparts a large energy gap (Eg) and a low triplet energy level (T1), enabling the preparation of high-color-purity blue-light devices. This also ensures the transfer of triplet excitons to the host, improving device lifespan. Para-substituted aromatic and heteroaromatic amino structures can narrow the emission spectrum, resulting in electroluminescent properties with high color purity. Fluorine atoms are introduced into the compounds of the present invention, and by introducing electron acceptor-type fluorine atoms, the electroluminescent emission wavelength of the compounds of the present invention can be effectively adjusted to obtain high-purity blue light devices. Furthermore, the introduction of electron-withdrawing F atoms can adjust the HOMO-LUMO distribution and enhance the HOMO-LUMO alternating distribution, resulting in compounds with suitable emission wavelengths and narrow half-widths, thereby improving the color purity of the device. Furthermore, the intermolecular and intramolecular hydrogen bonding forces can be modulated, resulting in decreased molecular polarity and effectively lowering the sublimation temperature. The C-F bond has excellent stability in electroluminescent devices, preventing the compounds of the present invention from decomposing in the device, which helps to increase the device life. The device life and efficiency prepared using the doping material of the present invention are significantly improved. DETAILED DESCRIPTION

[0063] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0064] Example 1

[0065]

[0066] Under nitrogen protection, the raw material 1-1 (40.00 mmol), the raw material 1-2 (40.00 mmol), sodium tert-butoxide (80.00 mmol), tris (dibenzylideneacetone) dipalladium (0.40 mmol), and tri-tert-butylphosphine (2.00 mmol) were dissolved in a dry toluene solution, and the temperature was raised to 90 ° C. under stirring, and the reaction was reacted for 8 h; the reaction was monitored by TCL plate. After the reaction was completed, the temperature was lowered to room temperature, water was added to quench the reaction, and the organic phase was separated and collected. It was filtered using diatomaceous earth to remove salts and catalysts; after the organic phases were combined, they were dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The intermediate 1-1 (10.21 g, yield 85.3%) was obtained by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V = 1:3);

[0067] Under nitrogen protection, intermediate 1-2 (30.00 mmol), raw material 1-3 (30.00 mmol), sodium tert-butoxide (60.00 mmol), tris(dibenzylideneacetone)dipalladium (0.30 mmol), and tri-tert-butylphosphine (1.50 mmol) were dissolved in dry toluene solution, and the temperature was raised to 80°C under stirring, and the reaction was carried out for 6 h. The reaction was monitored by TCL dot plate. After the reaction was completed, it was cooled to room temperature, and water was added to quench the reaction. After separation, the organic phase was collected and filtered using diatomaceous earth to remove salt and catalyst. After the organic phases were combined, they were dried using anhydrous magnesium sulfate and the solvent was removed using a rotary evaporator. The collected product was dissolved in methanol, recrystallized, filtered, and the filter cake was rinsed with methanol several times and dried in a 60°C oven for 5 h to obtain intermediate 1-2 (9.89 g, yield 88.0%).

[0068] Under nitrogen protection, intermediate 1-2 (20.00 mmol), sodium tert-butoxide (40.00 mmol), intermediate 1-1 (40.00 mmol), tris(dibenzylideneacetone)dipalladium (0.40 mmol), and tri-tert-butylphosphine (2.00 mmol) were dissolved in a toluene solution. The temperature was raised to 110°C under stirring and the reaction was allowed to react overnight. The reaction was monitored by TCL dot plate. After the reaction was completed, the mixture was cooled to room temperature and water was added to quench the reaction. After separation, the organic phase was collected and filtered using diatomaceous earth to remove salt and catalyst. The organic phases were combined, dried using anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The collected product was dissolved in methanol, recrystallized, filtered, and the filter cake was rinsed with methanol several times and dried in a 70°C oven for 5 h to obtain intermediate 1-3 (14.27 g, yield 84.9%).

[0069] Under a nitrogen atmosphere, intermediate 1-3 (13.14 mmol) was dissolved in o-dichlorobenzene solution and placed in a reaction flask. The nitrogen was replaced, and boron triiodide (26.30 mmol) was added dropwise. The temperature was slowly raised to 120-150 ° C. and stirring was continued overnight. After the reaction was completed, it was cooled to room temperature and DIPEA was added to adjust to neutrality. Water was added for extraction, and the organic phase was collected. The organic phase was removed by rotation and purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V = 1:3) to obtain compound 1 (6.3 g, yield 56.5%, MW: 847.89).

[0070] The obtained compound 1 was tested and analyzed, and the results were as follows:

[0071] HPLC purity: >99.8%.

[0072] Mass spectrometry test: theoretical value is 847.89; tested value is 847.63.

[0073] Elemental analysis:

[0074] Calculated values ​​are: C, 76.49; H, 5.23; B, 1.27; F, 4.48; N, 4.96; S, 7.56;

[0075] The test values ​​are: C, 76.60; H, 5.45; B, 1.12; F, 4.21; N, 5.3; S, 7.21.

[0076] Example 2

[0077]

[0078] Under nitrogen protection, the raw material 5-1 (80.00 mmol), the raw material 5-2 (80.00 mmol), tetrakistriphenylphosphine palladium (0.8 mmol), and potassium carbonate (160.00 mmol) were dissolved in toluene / ethanol / water (200 ml / 100 ml / 100 ml), and the temperature was raised to 100 ° C. under stirring, and the reaction was carried out for 8 h; the reaction was monitored by TCL plate. After the reaction was completed, the temperature was lowered to room temperature, the liquid was separated and the organic phase was retained. It was filtered using diatomaceous earth to remove salts and catalysts; after the organic phases were combined, they were dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The intermediate 5-1 (16.58 g, yield 79.9%) was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V = 1:5);

[0079] Under nitrogen protection, intermediate 5-1 (40.00 mmol), sodium tert-butoxide (80.00 mmol), raw material 1-2 (40.00 mmol), tris(dibenzylideneacetone)dipalladium (0.80 mmol), and tri-tert-butylphosphine (8.00 mmol) were dissolved in a toluene solution, and the temperature was raised to 100 ° C. under stirring, and the reaction was allowed to proceed overnight; the reaction was monitored by TCL dot plate. After the reaction was completed, it was cooled to room temperature, water was added to quench the reaction, and the organic phase was collected after separation and filtered using diatomaceous earth to remove salt and catalyst; the organic phases were combined, dried using anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The intermediate 5-2 (15.36 g, yield 89.0%) was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V=1:3).

[0080] Under nitrogen protection, the raw material 5-3 (40.00 mmol), the raw material 1-2 (40.00 mmol), sodium tert-butoxide (80.00 mmol), tris(dibenzylideneacetone)dipalladium (0.40 mmol), and tri-tert-butylphosphine (2.00 mmol) were dissolved in a dry toluene solution, and the temperature was raised to 90° C. with stirring, and the reaction was carried out for 8 h. The reaction was monitored by TCL plate. After the reaction was completed, the temperature was lowered to room temperature, and water was added to quench the reaction. The organic phase was separated and collected, and filtered through diatomaceous earth to remove salt and catalyst. After the organic phases were combined, they were dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The intermediate 5-3 (11.47 g, yield 85.0%) was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V=1:3);

[0081] Under nitrogen protection, intermediate 1-1 (20.0 mmol), intermediate 5-3 (20.00 mmol), sodium tert-butoxide (40.00 mmol), tris(dibenzylideneacetone)dipalladium (0.20 mmol), and tri-tert-butylphosphine (1.00 mmol) were dissolved in dry toluene solution, and the temperature was raised to 90° C. under stirring, and the reaction was reacted for 8 h. The reaction was monitored by TCL. After the reaction was completed, the temperature was lowered to room temperature, water was added to quench the reaction, and the organic phase was separated and collected. The organic phase was filtered using diatomaceous earth to remove salt and catalyst. After the organic phases were combined, they were dried over anhydrous magnesium sulfate and the solvent was removed using a rotary evaporator. The collected product was dissolved in methanol, recrystallized, filtered, and the filter cake was rinsed with methanol several times and dried in a 70° C. oven for 5 h to obtain intermediate 5-4 (11.20 g, yield 91.0%).

[0082] Under nitrogen protection, intermediate 5-2 (15.0 mmol), intermediate 5-4 (15.00 mmol), sodium tert-butoxide (30.00 mmol), tris(dibenzylideneacetone)dipalladium (0.20 mmol), and tri-tert-butylphosphine (0.90 mmol) were dissolved in dry toluene solution, and the temperature was raised to 90° C. under stirring, and the reaction was reacted for 8 h. The reaction was monitored by TCL. After the reaction was completed, the temperature was lowered to room temperature, water was added to quench the reaction, and the organic phase was collected and filtered using diatomaceous earth to remove salt and catalyst. After the organic phases were combined, they were dried over anhydrous magnesium sulfate and the solvent was removed using a rotary evaporator. The collected product was dissolved in methanol, recrystallized, filtered, and the filter cake was rinsed with methanol several times and dried in a 70° C. oven for 5 h to obtain intermediate 5-5 (13.21 g, yield 87.2%).

[0083] Under a nitrogen atmosphere, intermediate 5-5 (13.14 mmol) was dissolved in o-dichlorobenzene solution and placed in a reaction flask. The nitrogen was replaced, and boron triiodide (26.30 mmol) was added dropwise. The temperature was slowly raised to 120-150°C and stirred overnight. After the reaction was completed, it was cooled to room temperature and adjusted to neutral by adding DIPEA. Water was added for extraction, and the organic phase was collected and removed by rotary evaporation. The organic phase was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V = 1:3) to obtain compound 5 (6.0 g, yield 44.8%, MW: 1018.22). The obtained compound 5 was tested and analyzed, and the results are as follows:

[0084] HPLC purity: >99.8%.

[0085] Mass spectrometry test: theoretical value is 1018.22; tested value is 1018.10.

[0086] Elemental analysis:

[0087] Calculated values ​​are: C, 80.21; H, 6.43; B, 1.06; F, 1.87; N, 4.13; S, 6.30;

[0088] The test values ​​are: C, 80.42; H, 6.63; B, 0.93; F, 1.63; N, 4.32; S, 6.07.

[0089] Example 3

[0090]

[0091] Under nitrogen protection, raw material 1-1 (40.00 mmol), raw material 32-2 (40.00 mmol), sodium tert-butoxide (80.00 mmol), tris(dibenzylideneacetone)dipalladium (0.40 mmol), and tri-tert-butylphosphine (2.00 mmol) were dissolved in a dry toluene solution, and the temperature was raised to 90° C. under stirring, and the reaction was reacted for 8 h; the reaction was monitored by TCL plate. After the reaction was completed, the temperature was lowered to room temperature, and water was added to quench the reaction. The organic phase was separated and collected, and filtered using diatomaceous earth to remove salt and catalyst; after the organic phases were combined, they were dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The intermediate 32-1 (10.14 g, yield 89.5%) was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V=1:3);

[0092] Under nitrogen protection, the raw material 5-1 (80.00 mmol), the raw material 32-2 (80.00 mmol), tetrakistriphenylphosphine palladium (0.8 mmol), and potassium carbonate (160.00 mmol) were dissolved in toluene / ethanol / water (200 ml / 100 ml / 100 ml), and the temperature was raised to 100 ° C. under stirring, and the reaction was carried out for 8 h. The reaction was monitored by TCL. After the reaction was completed, the temperature was lowered to room temperature, the organic phase was retained, and filtered through diatomaceous earth to remove salt and catalyst. After the organic phases were combined, they were dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The intermediate 32-2 (20.31 g, yield 91.5%) was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V = 1:3);

[0093] Under nitrogen protection, intermediate 32-1 (40.00 mmol), raw material 32-2 (40.00 mmol), sodium tert-butoxide (80.00 mmol), tris(dibenzylideneacetone)dipalladium (0.40 mmol), and tri-tert-butylphosphine (2.00 mmol) were dissolved in dry toluene solution, and the temperature was raised to 90° C. under stirring, and the reaction was reacted for 8 h. The reaction was monitored by TCL. After the reaction was completed, the temperature was lowered to room temperature, and water was added to quench the reaction. The organic phase was separated and collected, and filtered through diatomaceous earth to remove salt and catalyst. After the organic phases were combined, they were dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The intermediate 32-3 (13.64 g, yield 81.7%) was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V=1:3).

[0094] Under nitrogen protection, raw material 1-1 (40.00 mmol), raw material 32-3 (40.00 mmol), sodium tert-butoxide (80.00 mmol), tris(dibenzylideneacetone)dipalladium (0.40 mmol), and tri-tert-butylphosphine (2.00 mmol) were dissolved in dry toluene solution. The temperature was raised to 90°C with stirring and the reaction was carried out for 8 hours. The reaction was monitored by TCL. After the reaction was completed, the temperature was lowered to room temperature and water was added to quench the reaction. The organic phase was separated and collected, and filtered through diatomaceous earth to remove salts and catalyst. After the organic phases were combined, they were dried over anhydrous magnesium sulfate and the solvent was removed using a rotary evaporator. The collected product was dissolved in methanol, recrystallized, filtered, and the filter cake was rinsed with methanol several times and dried in a 60°C oven for 6 hours to obtain intermediate 32-4 (17.94 g, yield 92.1%).

[0095] Under nitrogen protection, intermediate 32-4 (30.00 mmol), intermediate 32-1 (30.00 mmol), sodium tert-butoxide (60.00 mmol), tris(dibenzylideneacetone)dipalladium (0.30 mmol), and tri-tert-butylphosphine (1.80 mmol) were dissolved in dry toluene solution, and the temperature was raised to 90°C under stirring for 8 h. The reaction was monitored by TCL. After the reaction was completed, the temperature was lowered to room temperature, and water was added to quench the reaction. The organic phase was separated and collected, and filtered through diatomaceous earth to remove salt and catalyst. After the organic phases were combined, they were dried over anhydrous magnesium sulfate and the solvent was removed using a rotary evaporator. The collected product was dissolved in methanol, recrystallized, filtered, and the filter cake was rinsed with methanol several times and dried in a 60°C oven for 5 h to obtain intermediate 32-5 (18.31 g, yield 90.6%).

[0096] Under nitrogen protection, intermediate 32-5 (20.00 mmol), intermediate 32-3 (20.00 mmol), sodium tert-butoxide (40.00 mmol), tris(dibenzylideneacetone)dipalladium (0.20 mmol), and tri-tert-butylphosphine (1.00 mmol) were dissolved in dry toluene solution, and the temperature was raised to 120° C. under stirring, and the reaction was reacted for 8 h. The reaction was monitored by TCL. After the reaction was completed, the temperature was lowered to room temperature, and water was added to quench the reaction. The organic phase was separated and collected, and filtered through diatomaceous earth to remove salt and catalyst. The organic phases were combined, dried over anhydrous magnesium sulfate, and the solvent was removed using a rotary evaporator. The collected product was dissolved in methanol, recrystallized, filtered, and the filter cake was rinsed with methanol several times and dried in a 60° C. oven for 5 h to obtain intermediate 32-6 (16.76 g, yield 79.5%).

[0097] Under a nitrogen atmosphere, intermediate 32-6 (13.14 mmol) was dissolved in o-dichlorobenzene solution and placed in a reaction flask. The nitrogen was replaced, and boron triiodide (26.30 mmol) was added dropwise. The temperature was slowly raised to 120-150°C and stirring was continued overnight. After the reaction was completed, the mixture was cooled to room temperature and DIPEA was added to adjust to neutrality. The mixture was extracted with water, and the organic phase was collected and removed by rotation. The organic phase was purified by column chromatography using a mixed solution of dichloromethane and petroleum ether (V:V = 1:4) to obtain compound 36 (5.1 g, yield 36.5%, MW: 1062.21).

[0098] The obtained compound 36 was tested and analyzed, and the results were as follows:

[0099] HPLC purity: >99.8%.

[0100] Mass spectrometry test: theoretical value is 1062.21; tested value is 1062.56.

[0101] Elemental analysis:

[0102] Calculated values: C, 81.41; H, 7.02; B, 1.02; F, 3.58; N, 3.96; O, 3.01

[0103] The test values ​​are: C, 81.53; H, 7.11; B, 0.92; F, 3.12; N, 4.21; O, 3.08.

[0104] The synthesis methods of other compounds are the same as those in the above examples and are not described in detail here. The mass spectra, molecular formulas and yields of other synthesis examples are shown in Table 1 below:

[0105] Table 1

[0106]

[0107] Device Example 1: Fabrication of an organic electroluminescent device containing Compound 1

[0108] a. ITO Anode: A 150nm thick ITO (Indium Tin Oxide)-Ag-ITO (Indium Tin Oxide) glass substrate was cleaned twice in distilled water, ultrasonically washed for 30 minutes, then repeatedly rinsed twice in distilled water, ultrasonically washed for 10 minutes. After washing, it was transferred to a spin dryer for drying and finally baked in a vacuum oven at 220°C for 2 hours. After baking, it was cooled and ready for use. Using this substrate as the anode, the device was deposited using an evaporation machine, and other functional layers were sequentially deposited on it.

[0109] b. HIL (hole injection layer): The hole injection layer materials HT-01 and P-dopant were vacuum-deposited at a deposition rate of 97:3, and the thickness was 10 nm.

[0110] c. HTL (hole transport layer): At a deposition rate of 1%, 125 nm of HT-01 was vacuum-deposited on the hole injection layer as a hole transport layer.

[0111] d. Luminous auxiliary layer: At a deposition rate of 5 nm, 5 nm EBL-01 was vacuum-deposited on the hole transport layer as a light-emitting auxiliary layer.

[0112] e. EML (light-emitting layer): Then on the above-mentioned light-emitting auxiliary layer, The host material (Host) and the compound 1 provided in the above example as the dopant material (Dopant) were vacuum-deposited to a thickness of 20 nm as the light-emitting layer at a deposition rate of 100 nm. The chemical formula of the Host is shown below. The deposition rate ratio of the Host to the Dopant was 98:2.

[0113] f. HBL (hole blocking layer): At a deposition rate of , 5 nm of HBL-01 was vacuum-deposited on the light-emitting layer as a hole blocking layer.

[0114] g. ETL (Electron Transport Layer): 30nm of ET-01 and LiQ were vacuum evaporated on the hole blocking layer as the electron transport layer at a deposition rate of 1:1.

[0115] h. EIL (electron injection layer): The evaporation rate is 1.0 nm, and a Yb film layer is evaporated to form an electron injection layer.

[0116] i. Cathode: The evaporation rate ratio of magnesium and silver was 14nm, and the evaporation rate ratio was 1:9 to obtain an OLED device.

[0117] j. Light extraction layer: At a deposition rate of 100 nm, CPL-01 is vacuum-deposited on the cathode to a thickness of 67 nm as a light extraction layer. The substrate after deposition is then packaged. First, the cleaned cover is coated with UV adhesive using a coating machine. The coated cover is then moved to the lamination section, where the deposited substrate is placed on top of the cover. Finally, the substrate and cover are bonded together using a laminating machine, while the UV adhesive is cured by light.

[0118] The required material structure is as follows:

[0119]

[0120] Device Example 2 to Device Example 35 refer to the above method, and replace the compound 1 used in Device Example 1 with compounds 2, 5, 8, 9, 14, 21, 23, 29, 31, 32, 36, 50, 57, 64, 72, 76, 83, 95, 96, 101, 102, 113, 118, 125, 134, 146, 148, 157, 162, 167, 175, 180, and 186 as doping materials to prepare corresponding organic electroluminescent devices.

[0121] Device Comparative Example 1: This comparative example provides an organic electroluminescent device. The only difference between the preparation method of this organic electroluminescent device and that of Device Example 1 is that this organic electroluminescent device uses existing comparative compounds a, b, c, d, e, f, g, h, and i to replace the doping material in Device Example 1 for vapor deposition, thereby preparing Comparative Examples 1 to 9. The chemical structures of the comparative compounds a, b, c, d, e, f, g, h, and i are as follows:

[0122]

[0123] The driving voltage, luminous efficiency, BI value and lifespan of the organic electroluminescent devices obtained from the device examples 1 to 35 and the device comparative examples 1 to 9 were characterized at a brightness of 1000 (nits). The test results are shown in Table 2 below:

[0124] Table 2

[0125]

[0126]

[0127] In blue top-emitting devices, the current efficiency is greatly affected by chromaticity. Therefore, the influence of chromaticity on efficiency is taken into account, and the ratio of luminous efficiency to CIEy is defined as BI value, that is, BI = (cd / A) / CIEy.

[0128] As can be seen from the table above, the organic electroluminescent devices prepared using the compounds provided by the present invention as dopants in the light-emitting layer are comparable to the organic electroluminescent devices of Comparative Examples 1 to 4 prepared using Comparative Compounds a to d as dopants. Although the device lifespan meets the requirements and the luminous efficiency is similar, the increased CIEy results in impure blue luminescence from the devices, seriously affecting the device chromaticity and reducing the device BI value. The introduction of F in the present invention adjusts the luminescence peak position of the inventive material, reduces the device CIEy value, maintains the chromaticity of the inventive material, and obtains a purer blue light, further improving the device efficiency and lifespan, significantly improving the state of the art. Furthermore, compared to the device of Comparative Example 5 prepared using Comparative Compound e as a dopant material, the introduction of a strong electron-withdrawing F group at an inappropriate position results in a degraded HOMO / LUMO distribution, a low BI value, and an insufficient lifespan. Furthermore, compared to the devices of Comparative Examples 6 to 9 prepared using Comparative Compounds f to i as dopants, the introduction of benzothiophene, etc., increases the conjugated area of ​​the inventive material, further improving the oscillator strength, and achieving higher luminous efficiency and lifespan. The device lifespan is significantly improved, significantly improving the state of the art.

[0129] Among them, in Examples 5, 11, 21, 32, etc., the introduction of ortho-substituents significantly improves the lifespan and efficiency, which is a significant improvement in this field.

[0130] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

[0131] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A polycyclic aromatic compound, characterized in that: Specifically including the following structures: Among them, Et is ethyl, t-Bu is tert-butyl, t-Am is tert-amyl, and i-Pr is isopropyl.

2. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises an anode, a cathode, and an organic layer disposed between the anode and the cathode. The organic layer comprises a light-emitting layer. Raw materials of the light-emitting layer comprise a doping material and the polycyclic aromatic compound according to claim 1 .

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