Boron-containing compound and organic electroluminescent device containing the same

Abstract

The present invention relates to a novel organic compound having the structure of the following formula (1): Rings A, B, C, D, and E independently represent aromatic rings or heteroaromatic rings, and two adjacent rings can be fused to form a ring containing X 1 or X 2 A five-membered ring or a six-membered ring; X 1 and X 2 are independently selected from one of O, S, N, C, and Si; m and n are independently 0, 1 or 2, and R 1 To R 5 They are independently selected from hydrogen, C1-C10 chain alkyl, C3-C10 cycloalkyl, C1-C10 alkoxy, halogen, cyano, nitro, hydroxyl, ester, silyl, amino, arylamino, heteroarylamino, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, and at least one of them is of formula G. When the compound of the present invention is used as a light-emitting layer material in an OLED device, it exhibits excellent device performance and stability. The present invention also protects an organic electroluminescent device using the compound of the general formula.

Description

Technical Field

[0001] The invention relates to a boron-containing organic material, belonging to the technical field of organic luminescent materials. The invention also relates to the application of the compound in an organic electroluminescent device. Background Art

[0002] The main way for people to obtain information is through vision, so display devices are crucial in the process of human interaction with information. Organic light-emitting diodes (OLEDs) have many advantages such as flexibility, self-luminescence, high contrast, large size, and low power consumption, and have become one of the mainstream display devices.

[0003] Among them, red and green dyes, as the three primary colors, generally contain heavy atoms such as Ir and Pt, which can theoretically achieve 100% internal quantum efficiency, high electroluminescence efficiency, and low power consumption, becoming the mainstream of current commercial display devices. However, the chromaticity and life of blue phosphorescent materials do not meet the current commercial display requirements. At present, blue light devices still use traditional fluorescent materials to achieve high color purity and long device life.

[0004] Recently, Japanese researchers such as Takuji Hatakeyama and Junji Kido reported a series of organic materials DABNA-1 (Adv. Mater. 2016, 28, 2777–2781 J. Mater. Chem. C, 2019, 7, 3082-3089) based on BN resonance-type TADF (Thermally Activated Delayed Fluorescence). The boron atoms, nitrogen atoms and phenyl groups of this type of compound constitute a rigid polycyclic aromatic skeleton, thus having a higher fluorescence quantum yield. Compared with traditional blue fluorescent dyes, this type of compound has a narrower spectrum and high color purity. However, the rigid planar structure also leads to a large difference in energy levels between the singlet and triplet states, and the reverse intersystem crossing from the triplet state to the singlet state is slow. After the excitons recombine on the dye, they will cause severe efficiency roll-off and the device life is short. In addition, an overly planar rigid structure often leads to adverse effects such as spectral broadening and red shift due to excessive doping concentration.

[0005]

[0006] Existing organic electroluminescent materials still have much room for improvement in luminescence performance, and the industry urgently needs to develop new luminescent material systems to meet commercial needs. Summary of the invention

[0007] In order to solve the above technical problems, the present invention provides a new type of compound, which belongs to the thermally activated delayed fluorescent material. Aryl alkyl is introduced into the structure of this series of compounds to increase the molecular distance, inhibit molecular stacking and Dexter energy transfer, and thus improve the efficiency roll-off problem of organic electroluminescent devices using this type of compound; in addition, the aryl alkyl has an ideal anchoring effect, which can promote the molecules to be arranged parallel to the plane of the OLED substrate, which is beneficial to light extraction and improves the luminous efficiency.

[0008] The present invention provides a new type of boron-based organic compound, the structure of which is shown in the general formula (1):

[0009]

[0010] In the general formula (1):

[0011] Rings A, B, C, D, and E independently represent aromatic rings or heteroaromatic rings, and two adjacent rings may be fused to form a ring containing X 1 or X 2 A five-membered ring or a six-membered ring;

[0012] Preferably, ring A is fused with ring C to form a 1 or, ring B and ring D are fused to form a five-membered ring or a six-membered ring containing X 2 or, ring A and ring C are fused to form a five-membered ring or a six-membered ring containing X 1 At the same time, ring B and ring D are fused to form a five-membered ring or a six-membered ring containing X 2 A five-membered ring or a six-membered ring;

[0013] X 1 and X 2 Each independently selected from one of O, S, N, C and Si;

[0014] m is 0, 1 or 2. 1 When selected from O or S, m is 0; n is 0, 1 or 2, when X 2 When selected from O or S, n is 0;

[0015] R 1 , R 2 , R 3 , R 4 , R 5Each independently represents a monosubstituted to maximum permissible substituent, and each independently is selected from one or a combination of at least two of hydrogen, C1-C10 chain alkyl, C3-C10 cycloalkyl, C1-C10 alkoxy, halogen, cyano, nitro, hydroxyl, ester, silane, amino, substituted or unsubstituted C6-C30 arylamino, substituted or unsubstituted C3-C30 heteroarylamino, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl, R 1 , R 2 , R 3 , R 4 and R 5 At least one of them is of formula G;

[0016] In the general formula G: Z 1 Selected from C or Si;

[0017] R A , R B , R C are independently selected from one of C1-C10 chain alkyl, C3-C10 cycloalkyl, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted C3-C30 heteroaryl, and R A , R B and R C At least one of them is a substituted or unsubstituted C6-C30 aryl group or a substituted or unsubstituted C3-C30 heteroaryl group, and at least one of them is a C1-C10 chain alkyl group or a C3-C10 cycloalkyl group.

[0018] When the above-mentioned groups have substituents, the substituents are selected from one or a combination of at least two of halogen, cyano, carbonyl, C1-C12 alkyl, C3-C12 cycloalkyl, C2-C10 alkenyl, C1-C6 alkoxy or thioalkoxy, C6-C30 monocyclic aromatic or condensed aromatic, C3-C30 monocyclic heteroaryl or condensed heteroaryl.

[0019] It should be noted that, in the present invention, the maximum permissible substituents refer to the maximum number of substituents under the premise that the substituted groups meet the bonding requirements.

[0020] In the present specification, the expression of Ca to Cb represents that the number of carbon atoms in the group is a to b. Unless otherwise specified, the number of carbon atoms generally does not include the number of carbon atoms in the substituent.

[0021] In the present specification, the expression of a ring structure crossed by “—” indicates that the connection site is any position on the ring structure that can form a bond.

[0022] In the present specification, the substituted or unsubstituted C6-C30 aryl group is preferably a C6-C20 aryl group, more preferably a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, an indenyl group, a fluorenyl group and its derivatives, a fluoranthenyl group, a triphenylene group, a pyrenyl group, a peryl group, A group consisting of a tetraphenyl group and a naphthyl group. Specifically, the biphenyl group is selected from 2-biphenyl, 3-biphenyl and 4-biphenyl; the terphenyl group includes p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl and m-terphenyl-2-yl; the naphthyl group includes 1-naphthyl and 2-naphthyl; the anthracenyl group is selected from 1-anthracenyl, 2-anthracenyl and 9-anthracenyl; the fluorenyl group is selected from 1-fluorenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl and 9-fluorenyl; the fluorenyl derivative is selected from 9,9'-dimethylfluorene, 9,9'-spirobifluorene and benzofluorene; the pyrenyl group is selected from 1-pyrenyl, 2-pyrenyl and 4-pyrenyl; the tetraphenyl group is selected from 1-tetraphenyl, 2-tetraphenyl and 9-tetraphenyl.

[0023] The heteroatom described in the present invention generally refers to an atom or an atom group selected from N, O, S, P, Si and Se, preferably selected from N, O and S. The atom names described in the present invention include their corresponding isotopes. For example, hydrogen (H) includes 1 H (hydrogen or H), 2 H (deuterium or D), etc.; Carbon (C) includes 12 C. 13 C, etc.

[0024] In the present specification, the substituted or unsubstituted C3~C30 heteroaryl group is preferably a C4~C20 heteroaryl group, and more preferably a nitrogen-containing heteroaryl group, an oxygen-containing heteroaryl group, a sulfur-containing heteroaryl group, etc. Specific examples include: furyl, thienyl, pyrrolyl, benzofuranyl, benzothienyl, isobenzofuranyl, indolyl, dibenzofuranyl, dibenzothienyl, carbazole and derivatives thereof, wherein the carbazole derivative is preferably 9-phenylcarbazole, 9-naphthylcarbazole, benzocarbazole, dibenzocarbazole, or indolecarbazole.

[0025] In the present specification, the C1-C20 chain alkyl group is preferably a C1-C10 chain alkyl group, and more preferably a C1-C6 chain alkyl group, examples of which include methyl, ethyl, n-propyl, n-butyl, n-hexyl, n-octyl, isopropyl, isobutyl, and tert-butyl.

[0026] In the present specification, the C3-C12 cycloalkyl group includes a monocyclic alkyl group and a polycyclic alkyl group, and preferably a C1-C10 alkyl group and a C3-C10 cycloalkyl group.

[0027] Furthermore, in the general formula compounds of the present invention, the rings A, B, C, D, and E are independently selected from 5- to 8-membered aryl rings or 5- to 8-membered heteroaryl rings; preferably, the rings A, B, C, D, and E are independently selected from 6-membered aryl rings or 5-membered heteroaryl rings.

[0028] Furthermore, in the general formula compound described in the present invention, the rings A, B, C, D, and E are independently selected from one of substituted or unsubstituted C6-C30 aromatic groups and substituted or unsubstituted C3-C30 heteroaromatic groups; preferably, the rings A, B, C, D, and E are independently selected from the following substituted or unsubstituted groups: benzene ring, furan ring, thiophene ring, naphthalene ring, phenanthrene ring or carbazole ring.

[0029] Furthermore, the general compound of the present invention is selected from the following formula (2):

[0030]

[0031] Furthermore, the general compound of the present invention is selected from the following formula (3):

[0032]

[0033] In formula (3), rings C, D, R 1 , R 2 , R 3 , R 4 , R 5 The definitions of m and n are the same as those in the general formula (1), wherein X 1 and X 2 are independently selected from O, S or N, and X 1 and X 2 At least one of them is N.

[0034] Furthermore, the general formula compound of the present invention is selected from one of the following formulas (I), (II), (III), (IV), (V), (VI), (VII) or (VIII):

[0035]

[0036] Most preferably, the general compound of the present invention is selected from the following formula (I), (II) or (III):

[0037]

[0038] More preferably, formula G is the following formula G1:

[0039]

[0040] In formula G1:

[0041] RA and R B At least one of them is a C1-C10 chain alkyl group or a C3-C10 cycloalkyl group, R C1 One selected from hydrogen, C1-C10 chain alkyl, C3-C10 cycloalkyl, C1-C10 alkoxy, substituted or unsubstituted C6-C30 arylamino, substituted or unsubstituted C3-C30 heteroarylamino, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl;

[0042] More preferably, R A and R B At least one of the following is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, cyclopentyl, neopentyl, n-hexyl, cyclohexyl, neohexyl, n-heptyl, cycloheptyl, n-octyl or cyclooctyl, R C1 is selected from hydrogen, deuterium, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, phenyl, naphthyl, anthracenyl, thienyl, pyrrolyl, indolyl, carbazolyl or pyridyl.

[0043] Still further preferably, formula G is one of the following formulas a, b, c or d:

[0044]

[0045] Among them, R 6 , R 7 They are independently selected from one or a combination of at least two of hydrogen, deuterium, halogen, C1-C10 chain alkyl, C3-C10 cycloalkyl; most preferably, formula G is selected from formula a or formula c.

[0046] More preferably, the above R 6 , R 7 are independently selected from hydrogen, or are independently selected from one of the following groups:

[0047]

[0048] Most preferably, the R 6 , R 7 are each independently selected from hydrogen.

[0049] Further preferably, in the general formula compound of the present invention, the R 1 , R 2 , R 3 , R 4 , R 5 are independently selected from hydrogen, or are independently selected from one of the following groups:

[0050]

[0051] As preferred structures of the compounds of the present invention, the following specific compounds M1-M140 can be cited, but are not limited to these compounds:

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058] As another aspect of the present invention, there is also provided an application of the compound as described above in an organic electroluminescent device. Specifically, it is preferably used as a light-emitting layer material in an organic electroluminescent device, and more preferably used as a material in the light-emitting layer in the organic electroluminescent device, and specifically can be used as a luminescent dye.

[0059] As another aspect of the present invention, an organic electroluminescent device is provided, comprising a first electrode, a second electrode and one or more organic layers inserted between the first electrode and the second electrode, wherein the organic layer contains a compound of the general formula (1), (2) or (3) as described above, or contains a compound having the structure shown in M1-M140 as described above.

[0060] Specifically, an embodiment of the present invention provides an organic electroluminescent device, comprising 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 comprise a hole injection layer, a hole transport layer, a light-emitting layer and an electron transport layer, 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 a light-emitting layer is provided between the hole transport layer and the electron transport layer; wherein the light-emitting layer contains a compound of the general formula (1), (2) or (3) as described above, or contains a compound of the structure shown in M1-M140 as described above.

[0061] The present invention further discloses a display screen or a display panel, wherein the organic electroluminescent device as described above is adopted in the display screen or the display panel; preferably, the display screen or the display panel is an OLED display.

[0062] The present invention also discloses an electronic device, wherein the electronic device has a display screen or a display panel, and the display screen or the display panel adopts the organic electroluminescent device as described above.

[0063] The OLED device prepared by using the compound of the present invention has low starting voltage, high luminous efficiency and better service life, and can meet the requirements of current panel manufacturing companies for high-performance materials.

[0064] The specific reasons why the above compounds of the present invention have excellent performance as luminescent dyes and / or sensitizer materials in the light-emitting layer of an organic electroluminescent device are not clear, but it is speculated that the reasons may be as follows:

[0065] 1. The boron atom contained in the compound of the present invention has a resonance effect with the nitrogen atom in the same ring, so that this series of materials has the characteristics of narrow spectrum and thermally activated delayed fluorescence emission.

[0066] 2. The series of materials of the present invention contain quaternary carbon substituted with aromatic groups, which can further increase the molecular distance while ensuring the transmission capacity, inhibit the quenching caused by accumulation, further reduce the efficiency roll-off, and extend the device life.

[0067] In addition, the preparation process of the compound of the present invention is simple and easy, the raw materials are easily available, and it is suitable for mass production and expansion. DETAILED DESCRIPTION

[0068] The specific preparation method of the above-mentioned novel compound of the present invention will be described in detail below by taking a plurality of synthesis examples as examples, but the preparation method of the present invention is not limited to these synthesis examples.

[0069] It should be noted that obtaining the compound is not limited to the synthesis method and raw materials used in the present invention, and those skilled in the art may also select other methods or routes to obtain the compound proposed in the present invention. The compounds of the synthesis method not mentioned in the present invention are raw materials obtained through commercial channels, or are prepared by these raw materials according to known methods.

[0070] The solvents and reagents used in the present invention, such as dichloromethane, petroleum ether, ethanol, tert-butylbenzene, boron tribromide, carbazole, diphenylamine and other chemical reagents, can be purchased from the domestic chemical product market, such as Sinopharm Group Reagent Company, TCI Company, Shanghai Bid Pharmaceutical Company, Bailingwei Reagent Company, etc.

[0071] The synthesis method of the compound of the present invention is briefly described below.

[0072] Synthesis Example

[0073] Representative synthetic routes:

[0074]

[0075] The analysis and detection of the intermediates and compounds in the present invention were performed using an ABSCIEX mass spectrometer (4000QTRAP).

[0076] Synthesis Example 1: Synthesis of M1

[0077]

[0078] Synthesis of intermediate M1-1:

[0079] At room temperature, 1,3-dibromo-5-(2-phenylpropyl-2-yl)benzene (35.2g, 100mmol), diphenylamine (41.7g, 250mmol), Pd2(dba)3 (0.92g, 1mmol), s-Phos (0.82g, 2mmol), sodium tert-butoxide (24g, 250mmol), and xylene (500ml) were added to a 1L single-mouth bottle, replaced with nitrogen three times, and heated to 130°C for overnight reaction. The reaction solution was cooled to room temperature, the reaction system was concentrated, extracted with dichloromethane, washed with a large amount of water, and the organic phase was dried and concentrated for column chromatography (PE: DCM = 20:1) to obtain 42.4g of crude product, which was heated and washed with n-hexane to obtain 33.1g of white solid, with a yield of 62.4%.

[0080] The molecular ion mass determined by mass spectrometry was: 530.29 (theoretical value: 530.27).

[0081] Synthesis of compound M1:

[0082] M1-1 (5.3 g, 10 mmol) was added to a 250 ml three-necked flask, and p-tert-butylbenzene (80 ml) was added. After stirring for 20 minutes, the reaction system was cooled to -20 ° C, and then 15 mmol of tert-butyl lithium was added. The temperature was maintained at low temperature and continued to stir for 30 minutes. Then the temperature was gradually raised to 90 ° C and continued to heat for 3 hours. Finally, the temperature of the reaction system was lowered to -20 ° C again, and boron tribromide (5.1 g, 20 mmol) was added under nitrogen protection. After stirring for 30 minutes, diisopropylethylamine (13 g, 80 mmol) was added. Finally, the reaction system was heated to 110 ° C and reacted for 12 hours. After the reaction was cooled to room temperature, the organic phase was decompressed and dried. Ethyl acetate (200 ml) was extracted three times, and the organic phases were combined and dried over anhydrous sodium sulfate. The organic phase was mixed with silica gel and concentrated, and column chromatography (PE: DCM = 100: 1) was used to obtain 2.1 g of crude product, which was recrystallized from toluene / n-hexane to obtain 0.95 g of yellow solid, with a yield of 17.6%.

[0083] The molecular ion mass determined by mass spectrometry was: 538.22 (theoretical value: 538.26).

[0084] Synthesis Example 2: Synthesis of M6

[0085] The synthesis method is similar to that of M1, except that diphenylamine is replaced with an equal amount of di(4-tert-butylphenyl)amine to obtain compound M6 with a yield of 15.1%. The molecular ion mass determined by molecular mass spectrometry is 762.49 (theoretical value: 762.51).

[0086] Synthesis Example 3: Synthesis of M37

[0087] Synthesis of intermediate M37-1:

[0088] At room temperature, (1-(3,5-dibromophenyl)ethane-1,1-diphenyl)diphenyl (41.4 g, 100 mmol), di(4-tert-butylphenyl)amine (90.0 g, 320 mmol), Pd2(dba)3 (2.8 g, 3 mmol), s-Phos (1.2 g, 3 mmol), sodium tert-butoxide (33.6 g, 350 mmol), and xylene (1200 ml) were added to a 2L single-mouth bottle, replaced with nitrogen three times, and heated to 130°C to react overnight. The reaction solution was cooled to room temperature, extracted with ethyl acetate, washed with a large amount of water, and the organic phase was dried, concentrated, and column chromatography (PE: DCM = 20:1) was performed to obtain 66.4 g of white solid, with a yield of 81.4%.

[0089] The molecular ion mass determined by mass spectrometry was: 816.58 (theoretical value: 816.54).

[0090] Synthesis of compound M37:

[0091] M53-1 (8.2 g, 10 mmol) was added to a 500 ml three-necked flask, and p-tert-butylbenzene (150 ml) was added. After stirring for 20 minutes, the reaction system was cooled to -20 ° C, and then 15 mmol of tert-butyl lithium was added. The temperature was maintained at low temperature and continued to stir for 30 minutes. Then the temperature was gradually raised to 90 ° C and continued to heat for 3 hours. Finally, the temperature of the reaction system was lowered to -20 ° C again, and boron tribromide (5.1 g, 20 mmol) was added under nitrogen protection. After stirring for 30 minutes, diisopropylethylamine (13 g, 80 mmol) was added. Finally, the reaction system was heated to 110 ° C and reacted for 12 hours. After the reaction was cooled to room temperature, the organic phase was decompressed and dried. Ethyl acetate (200 ml) was extracted three times, and the organic phases were combined and dried over anhydrous sodium sulfate. The organic phase was mixed with silica gel and concentrated, and column chromatography (PE: DCM = 40: 1) was used to obtain 1.9 g of crude product, which was recrystallized from toluene / n-hexane to obtain 1.1 g of yellow solid with a yield of 13.3%. The molecular ion mass determined by mass spectrometry was: 824.54 (theoretical value: 824.52).

[0092] Synthesis Example 4: Synthesis of M49

[0093] The synthesis method is similar to that of M37, except that diphenylamine is replaced with an equal amount of di(3-tert-butylphenyl)amine to obtain compound M49 with a yield of 15.5%. The molecular ion mass determined by molecular mass spectrometry is 816.57 (theoretical value: 816.54).

[0094] Synthesis Example 5: Synthesis of M55

[0095] Synthesis of intermediate M55-1:

[0096] At room temperature, 1-bromo-2,3-dichlorobenzene (22.4 g, 100 mmol), bis(4-(2-phenylpropyl-2-yl)phenyl)amine (129.7 g, 320 mmol), Pd2(dba)3 (2.8 g, 3 mmol), s-Phos (1.2 g, 3 mmol), sodium tert-butoxide (33.6 g, 350 mmol), and xylene (1200 ml) were added to a 2L single-mouth bottle, replaced with nitrogen three times, and heated to 130°C to react overnight. The reaction solution was cooled to room temperature, extracted with ethyl acetate, washed with a large amount of water, and the organic phase was dried, concentrated, and column chromatography (PE: DCM = 15:1) was performed to obtain 60.8 g of white solid, with a yield of 66.2%.

[0097] The molecular ion mass determined by mass spectrometry was: 918.48 (theoretical value: 918.47).

[0098] Synthesis of compound M55:

[0099] M55-1 (9.2g, 10mmol) was added to a 500ml three-necked flask, and p-tert-butylbenzene (150ml) was added. After stirring for 20 minutes, the reaction system was cooled to -20°C, and then 15mmol tert-butyl lithium was added. The temperature was maintained at low temperature and continued to stir for 30 minutes. Then the temperature was gradually raised to 90°C and the heating was continued for 3h. Finally, the temperature of the reaction system was lowered to -20°C again, and boron tribromide (5.1g, 20mmol) was added under nitrogen protection. After stirring for 30 minutes, diisopropylethylamine (13g, 80mmol) was added. Finally, the reaction system was heated to 110°C and reacted for 12h. After the reaction was cooled to room temperature, the organic phase was decompressed and dried. Ethyl acetate (200ml) was extracted three times, and the organic phases were combined and dried over anhydrous sodium sulfate. The organic phase was mixed with silica gel and concentrated, and column chromatography (PE: DCM = 40: 1) was used to obtain 3.2g of crude product, which was recrystallized from toluene / n-hexane to obtain 2.3g of yellow solid, with a yield of 26.3%. The molecular ion mass determined by mass spectrometry was: 892.45 (theoretical value: 892.49).

[0100] Synthesis Example 6: Synthesis of M66

[0101] The synthesis method is similar to that of M55, except that 1-bromo-2,3-dichlorobenzene is replaced with an equal amount of 1-bromo-2,3-dichloro-5-methylbenzene to obtain compound M66 with a yield of 23.5%. The molecular ion mass determined by molecular mass spectrometry is 906.48 (theoretical value: 906.51).

[0102] Synthesis Example 7: Synthesis of M89

[0103]

[0104] Synthesis of intermediate M89-1:

[0105] 3,6-bis(2-phenylpropane-2-yl)carbazole (34.3 g, 85 mmol), 2-bromo-1,3-difluorobenzene (7.7 g, 40 mmol), cesium carbonate (32.6 g, 100 mmol), N,N-dimethylformamide (350 ml) were added to a 500 mL single-mouth bottle at room temperature. After nitrogen replacement for 3 times, the reaction was heated at 130 ° C overnight. After the reaction stopped, 500 ml of water was added and stirred for 10 min after cooling to room temperature. A large amount of white solid precipitated, which was filtered by suction. The filter cake was boiled and washed with ethanol for 2 h, cooled and filtered by suction to obtain 37.4 g of white solid product with a yield of 97.6%. The molecular ion mass determined by mass spectrometry was 958.42 (theoretical value: 958.39).

[0106] Synthesis of compound M89:

[0107] M89-1 (9.6 g, 10 mmol) was added to a 500 ml three-necked flask, and p-tert-butylbenzene (100 ml) was added. After stirring for 20 minutes, the reaction system was cooled to -20 ° C, and then 15 mmol of tert-butyl lithium was added. The temperature was maintained at low temperature and continued to stir for 30 minutes. Then the temperature was gradually raised to 90 ° C and continued to heat for 3 hours. Finally, the temperature of the reaction system was lowered to -20 ° C again, and boron tribromide (5.1 g, 20 mmol) was added under nitrogen protection. After stirring for 30 minutes, diisopropylethylamine (13 g, 80 mmol) was added. Finally, the reaction system was heated to 110 ° C and reacted for 12 hours. After the reaction was cooled to room temperature, the organic phase was decompressed and dried. Ethyl acetate (200 ml) was extracted three times, and the organic phases were combined and dried over anhydrous sodium sulfate. The organic phase was mixed with silica gel and concentrated, and column chromatography (PE: DCM = 40: 1) was used to obtain 1.9 g of crude product, which was recrystallized from toluene / n-hexane to obtain 1.2 g of yellow solid, with a yield of 20.3%. The molecular ion mass determined by mass spectrometry was: 888.47 (theoretical value: 888.46).

[0108] Synthesis Example 8: Synthesis of M90

[0109] The synthesis method is similar to that of M89, except that 2-bromo-1,3-difluorobenzene is replaced with an equal amount of 2-bromo-1,3-difluoro-5-methylbenzene to obtain compound M90 with a yield of 19.6%. The molecular ion mass determined by molecular mass spectrometry is 902.51 (theoretical value: 902.48).

[0110] Based on the same inventive concept, an embodiment of the present invention further provides an organic electronic light-emitting device comprising the compound of the above embodiment. OLED is used as an organic electronic light-emitting device as an example of a device for illustration below, but it should be understood that the following detailed description is not a limitation of the present invention, and those skilled in the art can extend the following detailed description to other organic electronic light-emitting devices.

[0111] In one embodiment, the OLED includes a first electrode and a second electrode, and a plurality of organic material layers between the electrodes. The organic material layer can be divided into a plurality of regions. For example, the organic material layer can include a hole transport region, a light emitting layer, and an electron transport region.

[0112] In a specific embodiment, a substrate may be used below the first electrode or above the second electrode. The substrate is a glass or polymer material with excellent mechanical strength, thermal stability, water resistance, and transparency. In addition, a thin film transistor (TFT) may also be provided on the substrate used as a display.

[0113] The first electrode can be formed by sputtering or depositing the material used as the first electrode on the substrate. When the first electrode is used as an anode, an oxide transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), zinc oxide (ZnO) and any combination thereof can be used. When the first electrode is used as a cathode, a metal or alloy such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag) and any combination thereof can be used.

[0114] The organic material layer can be formed on the electrode by vacuum thermal evaporation, spin coating, printing, etc. The compound used as the organic material layer can be organic small molecules, organic macromolecules and polymers, and combinations thereof.

[0115] The hole transport region is located between the anode and the light-emitting layer. The hole transport region can be a hole transport layer (HTL) of a single-layer structure, including a single-layer hole transport layer containing only one compound and a single-layer hole transport layer containing multiple compounds. The hole transport region can also be a multi-layer structure including at least one layer of a hole injection layer (HIL), a hole transport layer (HTL), and an electron blocking layer (EBL).

[0116] The material of the hole transport region can be selected from, but 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 such as the compounds shown in HT-1 to HT-34 below; or any combination thereof.

[0117]

[0118]

[0119] 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 use one or more compounds of HT-1 to HT-34 mentioned above, or one or more compounds of HI1-HI3 described below; or one or more compounds of HT-1 to HT-34 can be doped with one or more compounds of HI1-HI3 described below.

[0120]

[0121] The light-emitting layer includes a light-emitting dye (i.e., a dopant) that can emit different wavelength spectra, and can also include a host material (Host). In one aspect of the present invention, the light-emitting layer adopts fluorescent electroluminescence technology. The fluorescent host material of the light-emitting layer can be selected from, but not limited to, one or more combinations of BFH-1 to BFH-13 listed below.

[0122]

[0123] The OLED organic material layer may further include an electron transport region between the light emitting layer and the cathode. The electron transport region may be an electron transport layer (ETL) of a single-layer structure, including a single-layer electron transport layer containing only one compound and a single-layer electron transport layer containing multiple compounds. The electron transport region may also be a multilayer structure including at least one layer of an electron injection layer (EIL), an electron transport layer (ETL), and a hole blocking layer (HBL).

[0124] In a specific example, the electron transport layer material can be selected from but not limited to one or more combinations of ET-1 to ET-57 listed below.

[0125]

[0126]

[0127]

[0128] In one example, the device may further include an electron injection layer located between the electron transport layer and the cathode, and 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, Li and / or Ca.

[0129] Device Example 1

[0130] In Example 1, the device structure is as follows:

[0131] ITO (150nm) / HI-2 (10nm) / HT-2 (40nm) / BFH-4:M1 (30nm, 5wt%) / ET-59 (30nm) / LiF (1nm) / Al (150nm).

[0132] The organic electroluminescent device was prepared as follows: a glass plate coated with a transparent conductive layer of ITO (thickness 150 nm) was ultrasonically treated in a commercial cleaning agent, rinsed in deionized water, ultrasonically degreased in a mixed solvent of acetone:ethanol, baked in a clean environment until the water was completely removed, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam;

[0133] Place the glass substrate with the anode in a vacuum chamber and evacuate to 1×10 -5 ~1×10 -4 Pa, HI-2 and HT-2 were vacuum evaporated on the above anode layer as hole injection layer and hole transport layer, respectively, with an evaporation rate of 0.1 nm / s and an evaporation film thickness of 10 nm and 40 nm, respectively;

[0134] "BFH-4:M1 (30nm, 5%wt)" was vacuum-deposited on the hole transport layer as the light-emitting layer of the organic electroluminescent device. The deposition rate was 0.1nm / s and the total deposition film thickness was 30nm. "5%wt" refers to the doping ratio of the dye, that is, the mass ratio of the main material to M1 is 95:5.

[0135] ET-59 was vacuum-deposited on the light-emitting layer as the electron transport layer of the organic electroluminescent device, with a deposition rate of 0.1 nm / s and a total deposition film thickness of 30 nm;

[0136] 0.5 nm of LiF as an electron injection layer and 150 nm of Al as a cathode were vacuum-deposited on the electron transport layer.

[0137] The preparation process of device examples 2-12 and comparative examples 1-2 is the same as that of device example 1, except that dye M1 is replaced with compounds M3, M6, M14, M31, M44, M49, M55, M76, M81, M106 and M108 of the present invention, or M1 is replaced with compounds DABAN-1 and R1 in the prior art.

[0138]

[0139] The organic electroluminescent device prepared by the above process was subjected to the following performance tests:

[0140] At the same brightness, the driving voltage, current efficiency and device life of the organic electroluminescent devices prepared in Examples 1 to 12 and Comparative Examples 1-2 were measured using a digital source meter and a brightness meter. Specifically, the voltage was increased at a rate of 0.1 V per second, and the brightness of the organic electroluminescent device was measured when it reached 1000 cd / m 2 The voltage at the time of 1000 ms is the driving voltage, and the current density at this time is measured at the same time; the ratio of brightness to current density is the current efficiency; the efficiency roll-off is the ratio of (the efficiency at the maximum brightness minus the efficiency at the specified brightness) to the maximum efficiency; the life test of LT95 is as follows: use a brightness meter at 1000 cd / m 2 At the same brightness, the current is kept constant and the brightness of the organic electroluminescent device is measured to drop to 950cd / m 2 The time is in hours. Specific performance data is shown in Table 1 below.

[0141] Table 1

[0142]

[0143]

[0144] It can be seen from Table 1 above that when the compound of the present invention is used as a dye, the life of the device using the compound of the present invention is significantly improved compared to the comparative example using the compounds DABAN-1 and R1 in the prior art, and the luminous efficiency is also relatively high, the efficiency roll-off is reduced, and excellent device performance is shown. This is because the compound DABAN-1 in the prior art is too flat and densely packed, which causes severe quenching, and thus low efficiency and severe device roll-off. The steric hindrance of the three benzene rings in the B position of R1 is too high, resulting in poor carrier transport performance and thus a decrease in device efficiency. The compound of the present invention introduces a large sterically hindered aryl alkyl group into the rigid structure, which effectively inhibits the accumulation of molecules and Dexter energy transfer, and the stability of the device is improved, which is conducive to the practical application of the compound of the present invention.

[0145] Although the present invention has been described in conjunction with the embodiments, the present invention is not limited to the above embodiments. It should be understood that under the guidance of the concept of the present invention, those skilled in the art may make various modifications and improvements. The appended claims summarize the scope of the present invention.

[0146] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A compound of the general formula, as shown in one of the following formulas (I), (II) or (III): In formula (I), (II) or (III): R 1 , R 2 , R 3 , R 4 , R 5 Each independently represents monosubstituted to the maximum permissible substituents; R 1 , R 2 , R 3 , R 4 Each is independently selected from one or a combination of two of hydrogen, C1-C10 chain alkyl, C3-C10 cycloalkyl, and substituted or unsubstituted C6-C30 aryl; R 5 One or a combination of two selected from hydrogen, C1-C10 chain alkyl, C3-C10 cycloalkyl, C1-C10 silyl, and substituted or unsubstituted C6-C30 aryl; R 1 , R 2 , R 3 , R 4 and R 5 At least one of them is of formula G; In formula G1: Z 1 Selected from C or Si; R A , R B are independently selected from one of C1-C10 chain alkyl, C3-C10 cycloalkyl, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted C3-C30 heteroaryl, and R A and R B At least one of them is a C1-C10 chain alkyl group or a C3-C10 cycloalkyl group; C1 One selected from hydrogen, C1-C10 chain alkyl, C3-C10 cycloalkyl, C1-C10 alkoxy, substituted or unsubstituted C6-C30 arylamino, substituted or unsubstituted C3-C30 heteroarylamino, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl; When the above-mentioned groups have substituents, the substituents are selected from one of C1-C12 alkyl groups, C3-C12 cycloalkyl groups, and C6-C30 aryl groups.

2. The compound of the general formula according to claim 1, R A and R B At least one of the following is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, n-pentyl, sec-pentyl, cyclopentyl, neopentyl, n-hexyl, cyclohexyl, neohexyl, n-heptyl, cycloheptyl, n-octyl or cyclooctyl, R C1 is selected from hydrogen, deuterium, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, phenyl, naphthyl, anthracenyl, thienyl, pyrrolyl, indolyl, carbazolyl or pyridyl.

3. The compound of the general formula according to claim 1, wherein G1 is one of the following formulas a or c: in, R 6 , R 7 Each is independently selected from one or a combination of two of hydrogen, deuterium, halogen, C1-C10 chain alkyl, and C3-C10 cycloalkyl.

4. The compound of the general formula according to claim 3, wherein The R 6 , R 7 are independently selected from hydrogen, or are independently selected from one of the following groups:

5. The compound of the general formula according to claim 4, wherein R 6 , R 7 are each independently selected from hydrogen.

6. The compound of the general formula according to claim 1, wherein The R 1 , R 2 , R 3 , R 4 , R 5 are independently selected from hydrogen, or are independently selected from one of the following groups:

7. The compound of the general formula according to claim 1 is selected from the following specific structural compounds:

8. Use of the compound according to any one of claims 1 to 7 as a light-emitting layer material in an organic electroluminescent device.

9. An organic electroluminescent device comprising a first electrode, a second electrode and one or more organic layers inserted between the first electrode and the second electrode, characterized in that: The organic layer comprises at least one compound according to any one of claims 1 to 7.

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