Organic compound, electroluminescent material, and use thereof
11793071 · 2023-10-17
Assignee
Inventors
Cpc classification
H10K85/6572
ELECTRICITY
C07D487/22
CHEMISTRY; METALLURGY
International classification
C07D487/22
CHEMISTRY; METALLURGY
Abstract
Provided are an organic compound, an electroluminescent material, and a use thereof. The organic compound has a structure represented by Formula I and is a carbazole olefin-like compound which is beneficial for improving the amorphous performance, thermal stability, and glass transition temperature of the material. The organic compound has appropriate HOMO energy level and LUMO energy level and a relatively high triplet energy level and can inhabit the transfer of triplet energy from a guest back to a host and reduce a driving voltage of a device. The organic compound, as a host material, has a relatively high carrier transport rate and balanced carrier transport performance, so as to facilitate the balance of hole and electron currents in the device, obtain a wider carrier recombination region, significantly improve light emitting efficiency and external quantum efficiency of the device, and reduce a turn-on voltage and power consumption of the device.
Claims
1. An organic compound having a structure represented by Formula I: ##STR00045## wherein R.sub.1 and R.sub.2 are each independently selected from any one of substituted or unsubstituted C6 to C30 aryl and substituted or unsubstituted C2 to C30 heteroaryl; wherein R.sub.11, R.sub.12, R.sub.13, and R.sub.14 are each independently selected from any one of halogen, cyano, substituted or unsubstituted C1 to C20 straight or branched chain alkyl, C1 to C20 alkoxy, C1 to C20 alkylthio, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C6 to C30 aryl, and substituted or unsubstituted C2 to C30 heteroaryl; wherein n.sub.1 and n.sub.4 are each independently selected from an integer between 0 and 2; and wherein n.sub.2 and n.sub.3 are each independently selected from an integer between 0 and 3.
2. The organic compound according to claim 1, wherein substituents in substituted aryl, substituted heteroaryl, substituted straight or branched chain alkyl, and substituted cycloalkyl are each independently selected from at least one of halogen, cyano, halogenated or unsubstituted C1 to C10 straight or branched chain alkyl, C6 to C18 aryl, C2 to C18 heteroaryl, C6 to C18 arylamino, C1 to C10 alkoxy, and C1 to C10 alkylthio.
3. The organic compound according to claim 1, wherein R.sub.1 and R.sub.2 are each independently selected from any one of the following groups or any one of the following groups substituted with a substituent: ##STR00046## wherein the dashed line represents a linkage site of the group; and wherein the substituent is selected from at least one of halogen, cyano, halogenated or unsubstituted C1 to C10 straight or branched chain alkyl, C6 to C18 aryl, C2 to C18 heteroaryl, C1 to C10 alkoxy, and C1 to C10 alkylthio.
4. The organic compound according to claim 1, wherein R.sub.1 and R.sub.2 are each independently selected from any one of the following groups: ##STR00047## wherein the dashed line represents a linkage site of the group; wherein X.sub.1 is selected from O, S, or N—R.sub.N2; wherein X.sub.2 is selected from O, S, N—R.sub.N3, or CR.sub.C1R.sub.C2; wherein R.sub.N1, R.sub.N2, R.sub.N3, R.sub.C1, and R.sub.C2 are each independently selected from hydrogen, unsubstituted or R.sub.x1-substituted C1 to C10 straight or branched chain alkyl, unsubstituted or R.sub.x1-substituted C6 to C18 aryl, or unsubstituted or R.sub.x1-substituted C2 to C18 heteroaryl; wherein R.sub.21, R.sub.22, R.sub.23, and R.sub.x1 are each independently selected from any one of halogen, cyano, halogenated or unsubstituted C1 to C10 straight or branched chain alkyl, C6 to C18 aryl, C2 to C18 heteroaryl, C6 to C18 arylamino, C1 to C10 alkoxy, and C1 to C10 alkylthio; wherein m.sub.1 is selected from an integer between 0 and 3; wherein m.sub.2 and m.sub.6 are each independently selected from an integer between 0 and 5; and wherein m.sub.3, m.sub.4, and m.sub.5 are each independently selected from an integer between 0 and 4.
5. The organic compound according to claim 4, wherein R.sub.1 and R.sub.2 are each independently selected from any one of the following groups or any one of the following groups substituted with a substituent: ##STR00048## wherein the dashed line represents a linkage site of the group; and wherein the substituent is selected from at least one of halogen, cyano, halogenated or unsubstituted C1 to C10 straight or branched chain alkyl, C6 to C18 aryl, C2 to C18 heteroaryl, C1 to C10 alkoxy, and C1 to C10 alkylthio.
6. The organic compound according to claim 1, wherein R.sub.1 and R.sub.2 are each independently selected from any one of the following groups: ##STR00049## wherein the dashed line represents a linkage site of the group; wherein R.sub.31 is each independently selected from any one of halogen, cyano, halogenated or unsubstituted C1 to C10 straight or branched chain alkyl, C6 to C18 aryl, C2 to C18 heteroaryl, C1 to C10 alkoxy, and C1 to C10 alkylthio; wherein t.sub.1 is selected from an integer between 0 and 4; wherein t.sub.2 is selected from an integer between 0 and 3; wherein t.sub.3 is selected from an integer between 0 and 2; wherein t.sub.4 is selected from an integer between 0 and 6; and wherein t.sub.5 is selected from an integer between 0 and 5.
7. The organic compound according to claim 1, wherein R.sub.1 and R.sub.2 are each independently selected from any one of the following groups or any one of the following groups substituted with a substituent: ##STR00050## wherein the dashed line represents a linkage site of the group; and wherein the substituent is selected from at least one of halogen, cyano, halogenated or unsubstituted C1 to C10 straight or branched chain alkyl, C6 to C18 aryl, C2 to C18 heteroaryl, C1 to C10 alkoxy, and C1 to C10 alkylthio.
8. The organic compound according to claim 1, wherein R.sub.1 and R.sub.2 are the same substituent.
9. The organic compound according to claim 1, wherein at least one of R.sub.1 and R.sub.2 is an electron withdrawing group.
10. The organic compound according to claim 1, wherein R.sub.11, R.sub.12, R.sub.13, and R.sub.14 are each independently selected from halogen, cyano, substituted or unsubstituted C1 to C5 straight or branched chain alkyl, substituted or unsubstituted C6 to C12 aryl, and substituted or unsubstituted C2 to C12 heteroaryl; and the substituent is selected from at least one of halogen, cyano, halogenated or unsubstituted C1 to C5 straight or branched chain alkyl.
11. The organic compound according to claim 10, wherein R.sub.11, R.sub.12, R.sub.13, and R.sub.14 are each independently selected from any one of halogen, cyano, C1 to C3 straight or branched chain alkyl, unsubstituted or R′-substituted phenyl, unsubstituted or R′-substituted biphenyl, unsubstituted or R′-substituted naphthyl, unsubstituted or R′-substituted pyridyl, unsubstituted or R′-substituted pyrazinyl, unsubstituted or R′-substituted triazinyl, unsubstituted or R′-substituted quinolyl, unsubstituted or R′-substituted isoquinolyl, unsubstituted or R′-substituted benzoxazolyl, unsubstituted or R′-substituted pyrimidinyl; wherein R′ is selected from halogen or cyano.
12. The organic compound according to claim 1, wherein the organic compound is selected from any one of the following compounds M1 to M80: ##STR00051## ##STR00052## ##STR00053## ##STR00054## ##STR00055## ##STR00056## ##STR00057## ##STR00058## ##STR00059## ##STR00060## ##STR00061## ##STR00062## ##STR00063## ##STR00064## ##STR00065## ##STR00066## ##STR00067## ##STR00068##
13. An electroluminescent material, comprising the organic compound according to claim 1.
14. A display panel, comprising an organic light emitting diode (OLED) device, wherein the OLED device comprises an anode, a cathode and an organic thin film layer disposed between the anode and the cathode, the organic thin film layer comprises a light emitting layer whose material comprises the electroluminescent material according to claim 13.
15. The display panel according to claim 14, wherein the electroluminescent material is used as a phosphorescent host material of the light emitting layer.
Description
BRIEF DESCRIPTION OF DRAWINGS
(1)
DETAILED DESCRIPTION
(2) The solutions of the present disclosure are further described below through specific examples. Those skilled in the art should understand that the examples described herein are used for a better understanding of the present disclosure and should not be construed as specific limitations to the present disclosure.
(3) A first object of the present disclosure is to provide an organic compound, where the organic compound has a structure represented by Formula I:
(4) ##STR00002##
(5) In Formula I, R.sub.1 and R.sub.2 are each independently selected from any one of substituted or unsubstituted C6 to C30 aryl and substituted or unsubstituted C2 to C30 heteroaryl.
(6) In Formula I, R.sub.11, R.sub.12, R.sub.13, and R.sub.14 are each independently selected from any one of halogen, cyano, substituted or unsubstituted C1 to C20 straight or branched chain alkyl, C1 to C20 alkoxy, C1 to C20 alkylthio, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C6 to C30 aryl, and substituted or unsubstituted C2 to C30 heteroaryl.
(7) In Formula I, n.sub.1 and n.sub.4 are each independently selected from an integer between 0 and 2, for example, 0, 1, or 2.
(8) In Formula I, n.sub.2 and n.sub.3 are each independently selected from an integer between 0 and 3, for example, 0, 1, 2, or 3.
(9) In the present disclosure, C6 to C30 may each independently be C6, C8, C10, C12, C13, C14, C15, C16, C18, C20, C22, C24, C26, or C28, etc.
(10) C2 to C30 may each independently be C2, C3, C4, C5, C6, C8, C10, C12, C13, C14, C15, C16, C18, C20, C22, C24, C26, or C28, etc.
(11) C1 to C20 may each independently be C2, C3, C4, C5, C6, C8, C10, C12, C14, C16, C18, or C19, etc.
(12) C3 to C20 may each independently be C4, C5, C6, C8, C10, C12, C13, C14, C15, C16, C18, or C19, etc.
(13) In the present disclosure, halogen includes fluorine, chlorine, bromine, or iodine. The same expression hereinafter has the same meaning.
(14) The organic compound provided by the present disclosure has a carbazole olefin-like structure which endows an intramolecular group of the organic compound with a non-planar configuration and is beneficial for improving the amorphous performance, thermal stability, and glass transition temperature of the material, where T.sub.g reaches 112 to 126° C.; and the organic compound has good thermal stability and film formability, so as to facilitate the formation of a stable and uniform thin film in a vacuum thermal evaporation process, reduce phase separation, and maintain device stability. Through a special design of a molecular structure, the organic compound has a relatively high triplet energy level T.sub.1 which reaches 2.89 to 3.03 eV, thereby inhibiting the transfer of triplet energy from a guest back to a host and confining triplet excitons in a light emitting layer; meanwhile, the organic compound has an appropriate HOMO energy level and LUMO energy level which can match an energy level of an adjacent carrier transport layer, to reduce hole and electron injection barriers and reduce a driving voltage of the device.
(15) The organic compound provided by the present disclosure is appropriate for use as a phosphorescent host material of an OLED device, and has a triplet energy level higher than that of a blue guest (a triplet energy level of a blue FIrpic guest is 2.65 eV, and triplet energy levels of deep blue FCNIrpic and FIr6 guests are 2.74 eV and 2.73 eV respectively), so the organic compound is especially appropriate for being applied in blue phosphorescent OLEDs.
(16) In an embodiment, substituents in substituted aryl, substituted heteroaryl, substituted straight or branched chain alkyl, and substituted cycloalkyl are each independently selected from at least one of halogen, cyano, halogenated or unsubstituted C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) straight or branched chain alkyl, C6 to C18 (for example, C6, C9, C10, C12, C14, C16, or C18, etc.) aryl, C2 to C18 (for example, C3, C4, C5, C6, C8, C10, C12, C14, C16, or C18, etc.) heteroaryl, C6 to C18 (for example, C6, C9, C10, C12, C14, C16, or C18, etc.) arylamino, C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) alkoxy, and C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) alkylthio.
(17) In an embodiment, R.sub.1 and R.sub.2 are each independently selected from any one of the following groups or any one of the following groups substituted with a substituent:
(18) ##STR00003## ##STR00004##
where the dashed line represents a linkage site of the group.
(19) In an embodiment, the substituent is selected from at least one of halogen, cyano, halogenated or unsubstituted C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) straight or branched chain alkyl, C6 to C18 (for example, C6, C9, C10, C12, C14, C16, or C18, etc.) aryl, C2 to C18 (for example, C3, C4, C5, C6, C8, C10, C12, C14, C16, or C18, etc.) heteroaryl, C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) alkoxy, and C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) alkylthio.
(20) In an embodiment, R.sub.1 and R.sub.2 are each independently selected from any one of the following groups:
(21) ##STR00005##
where the dashed line represents a linkage site of the group. X.sub.1 is selected from O, S, or N—R.sub.N2. X.sub.2 is selected from O, S, N—R.sub.N3, or CR.sub.C1R.sub.C2. R.sub.N1, R.sub.N2, R.sub.N3, R.sub.C1, and R.sub.C2 are each independently selected from hydrogen, unsubstituted or RA-substituted C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) straight or branched chain alkyl, unsubstituted or R.sub.x1-substituted C6 to C18 (for example, C6, C9, C10, C12, C14, C16, or C18, etc.) aryl, and unsubstituted or R.sub.x1-substituted C2 to C18 (for example, C3, C4, C5, C6, C8, C10, C12, C14, C16, or C18, etc.) heteroaryl. R.sub.21, R.sub.22, R.sub.23, and R.sub.x1 are each independently selected from any one of halogen, cyano, halogenated or unsubstituted C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) straight or branched chain alkyl, C6 to C18 (for example, C6, C9, C10, C12, C14, C16, or C18, etc.) aryl, C2 to C18 (for example, C3, C4, C5, C6, C8, C10, C12, C14, C16, or C18, etc.) heteroaryl, C6 to C18 (for example, C6, C9, C10, C12, C14, C16, or C18, etc.) arylamino, C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) alkoxy, and C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) alkylthio. m.sub.1 is selected from an integer between 0 and 3, for example, 0, 1, 2, or 3. m.sub.2 and m.sub.6 are each independently selected from an integer between 0 and 5, for example, 0, 1, 2, 3, 4, or 5. m.sub.3, m.sub.4, and m.sub.5 are each independently selected from an integer between 0 and 4, for example, 0, 1, 2, 3, or 4.
(22) In an embodiment, R.sub.1 and R.sub.2 are each independently selected from any one of the following groups or any one of the following groups substituted with a substituent:
(23) ##STR00006##
where the dashed line represents a linkage site of the group.
(24) The substituent is selected from at least one of halogen, cyano, halogenated or unsubstituted C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) straight or branched chain alkyl, C6 to C18 (for example, C6, C9, C10, C12, C14, C16, or C18, etc.) aryl, C2 to C18 (for example, C3, C4, C5, C6, C8, C10, C12, C14, C16, or C18, etc.) heteroaryl, C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) alkoxy, and C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) alkylthio.
(25) In an embodiment, R.sub.1 and R.sub.2 are each independently selected from any one of the following groups:
(26) ##STR00007##
where the dashed line represents a linkage site of the group. R.sub.31 is each independently selected from any one of halogen, cyano, halogenated or unsubstituted C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) straight or branched chain alkyl, C6 to C18 (for example, C6, C9, C10, C12, C14, C16, or C18, etc.) aryl, C2 to C18 (for example, C3, C4, C5, C6, C8, C10, C12, C14, C16, or C18, etc.) heteroaryl, C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) alkoxy, and C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) alkylthio. t.sub.1 is selected from an integer between 0 and 4, for example, 0, 1, 2, 3, or 4. t.sub.2 is selected from an integer between 0 and 3, for example, 0, 1, 2, or 3. t.sub.3 is selected from an integer between 0 and 2, for example, 0, 1, or 2. t.sub.4 is selected from an integer between 0 and 6, for example, 0, 1, 2, 3, 4, 5, or 6. t.sub.5 is selected from an integer between 0 and 5, for example, 0, 1, 2, 3, 4, or 5.
(27) In an embodiment, R.sub.1 and R.sub.2 are each independently selected from any one of the following groups or any one of the following groups substituted with a substituent:
(28) ##STR00008##
where the dashed line represents a linkage site of the group.
(29) The substituent is selected from at least one of halogen, cyano, halogenated or unsubstituted C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) straight or branched chain alkyl, C6 to C18 (for example, C6, C9, C10, C12, C14, C16, or C18, etc.) aryl, C2 to C18 (for example, C3, C4, C5, C6, C8, C10, C12, C14, C16, or C18, etc.) heteroaryl, C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) alkoxy, and C1 to C10 (for example, C2, C3, C4, C5, C6, C7, C8, or C9) alkylthio.
(30) In an embodiment, R.sub.1 and R.sub.2 are the same substituent.
(31) In an embodiment, at least one of R.sub.1 or R.sub.2 is an electron withdrawing group.
(32) In the present disclosure, the “electron withdrawing group” refers to a group capable of reducing an electron cloud density on a benzene ring and illustratively includes, but is not limited to, cyano, cyano-substituted aryl or heteroaryl, nitrogen-containing heteroaryl (such as pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, triazinyl, quinolyl, isoquinolyl, benzopyrazinyl, benzopyridazinyl, benzopyrimidinyl, pyridopyridyl, or pyridopyrazinyl), a fluorine-containing substituent (such as fluorine, trifluoromethyl, or perfluoroethyl), and aryl or heteroaryl substituted with the fluorine-containing substituent, etc.
(33) In an embodiment, R.sub.11, R.sub.12, R.sub.13, and R.sub.14 are each independently selected from halogen, cyano, substituted or unsubstituted C1 to C5 (for example, C1, C2, C3, C4, or C5) straight or branched chain alkyl, substituted or unsubstituted C6 to C12 (for example, C6, C9, C10, or C12, etc.) aryl, or substituted or unsubstituted C2 to C12 (for example, C3, C4, C5, C6, C9, C10, or C12, etc.) heteroaryl; and the substituent is selected from at least one of halogen, cyano, and halogenated or unsubstituted C1 to C5 (for example, C1, C2, C3, C4, or C5) straight or branched chain alkyl.
(34) In an embodiment, R.sub.11, R.sub.12, R.sub.13, and R.sub.14 are each independently selected from any one of halogen, cyano, C1 to C3 straight or branched chain alkyl (for example, methyl, ethyl, n-propyl, or isopropyl), unsubstituted or R′-substituted phenyl, unsubstituted or R′-substituted biphenyl, unsubstituted or R′-substituted naphthyl, unsubstituted or R′-substituted pyridyl, unsubstituted or R′-substituted pyrazinyl, unsubstituted or R′-substituted triazinyl, unsubstituted or R′-substituted quinolyl, unsubstituted or R′-substituted isoquinolyl, unsubstituted or R′-substituted benzoxazolyl, and unsubstituted or R′-substituted pyrimidinyl; where R′ is selected from halogen or cyano.
(35) In an embodiment, the organic compound is selected from any one of the following compounds M1 to M80:
(36) ##STR00009## ##STR00010## ##STR00011## ##STR00012## ##STR00013## ##STR00014## ##STR00015## ##STR00016## ##STR00017## ##STR00018## ##STR00019## ##STR00020## ##STR00021## ##STR00022## ##STR00023## ##STR00024## ##STR00025## ##STR00026##
(37) The organic compound having a structure represented by Formula I in the present disclosure is exemplarily prepared according to the following synthesis route:
(38) ##STR00027## ##STR00028##
(39) In the above synthesis route, X.sub.1 and X.sub.2 are each independently selected from halogen (such as fluorine, chlorine, bromine, or iodine), and R.sub.1, R.sub.2, R.sub.11, R.sub.12, R.sub.13, R.sub.14, n.sub.1, n.sub.2, n.sub.3, and n.sub.4 are each independently as defined in Formula I.
(40) A second object of the present disclosure is to provide an electroluminescent material including the organic compound as described for the first object.
(41) A third object of the present disclosure is to provide a display panel. The display panel includes an OLED device, the OLED device includes an anode, a cathode and an organic thin film layer disposed between the anode and the cathode, and a material of the organic thin film layer includes the electroluminescent material as described for the second object.
(42) In an embodiment, the organic thin film layer includes a light emitting layer whose material includes the electroluminescent material as described for the second object.
(43) In an embodiment, the electroluminescent material is used as a phosphorescent host material of the light emitting layer.
(44) In an embodiment, the organic thin film layer further includes any one or a combination of at least two of a hole transport layer, a hole injection layer, an electron blocking layer, a hole blocking layer, an electron transport layer, and an electron injection layer.
(45) In the OLED device of the present disclosure, a material of the anode may be a metal, a metal oxide, or a conductive polymer, where the metal includes copper, gold, silver, iron, chromium, nickel, manganese, palladium, and platinum, etc. as well as alloys thereof, the metal oxide includes indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide, and indium gallium zinc oxide (IGZO), etc., and the conductive polymer includes polyaniline, polypyrrole, and poly(3-methylthiophene), etc. In addition to the above materials that facilitate hole injection and combinations thereof, the material of the anode further includes known materials suitable for use as the anode.
(46) In the OLED device, a material of the cathode may be a metal or a multilayer metal material, where the metal includes aluminum, magnesium, silver, indium, tin, and titanium, etc. as well as alloys thereof, and the multilayer metal material includes LiF/Al, LiO.sub.2/Al, and BaF.sub.2/Al, etc. In addition to the above materials that facilitate electron injection and combinations thereof, the material of the cathode further includes known materials suitable for use as the cathode.
(47) In the OLED device, the organic thin film layer includes at least one light emitting layer (EML) and any one or a combination of at least two of a hole transport layer (HTL), a hole injection layer (HIL), an electron blocking layer (EBL), a hole blocking layer (HBL), an electron transport layer (ETL), and an electron injection layer (EIL) which is(are) disposed on two sides of the at least one light emitting layer, where the hole/electron injection and transport layers may include carbazole compounds, arylamine compounds, benzimidazole compounds, and metal compounds, etc. The OLED device may further be provided with a capping layer (CPL) disposed on the cathode (a side of the cathode facing away from the anode).
(48) As shown in
(49) The OLED device may be prepared by the following method: forming the anode on a transparent or opaque smooth substrate, forming organic thin layers on the anode, and forming the cathode on the organic thin layers. The organic thin layers may be formed by using known film forming methods such as evaporation, sputtering, spin coating, impregnation, and ion plating.
(50) A fourth object of the present disclosure is to provide an electronic apparatus including the display panel as described for the third object.
(51) Examples of the organic compound of the present disclosure are illustratively listed below.
Example 1
(52) This example provides an organic compound M1 having the following structure:
(53) ##STR00029##
(54) A preparation method for the organic compound M1 includes steps described below.
(55) ##STR00030##
(56) Compound A (4.02 g, 10 mmol), compound B (1.91 g, 20 mmol), 150 mL of toluene without water and oxygen, sodium t-butoxide (NaOt-Bu) (2.88 g, 30 mmol), tris(dibenzalacetone)dipalladium (Pd.sub.2(dba).sub.3) (0.18 g, 0.2 mmol), and tri-t-butylphosphine P(t-Bu).sub.3 (0.1 mL of 10% toluene solution) were sequentially added to a 250 mL three-necked flask and reacted at 120° C. for 24 h under a nitrogen atmosphere. The reaction solution was cooled to room temperature, poured into 200 mL of iced water, and extracted three times with dichloromethane. The organic phases were combined, spun into silica gel, and separated and purified through column chromatography (the mobile phase was a mixed solution of dichloromethane and n-hexane at a volume ratio of 1:1) to obtain compound C.
(57) Characterization Results of Compound C:
(58) .sup.1H-NMR (400 MHz, CDCl.sub.3): δ 8.30 (d, J=7.5 Hz, 2H), 8.20-8.08 (m, 4H), 7.94 (s, 2H), 7.67 (dd, J=7.5, 1.5 Hz, 1H), 7.38 (t, J=7.5 Hz, 2H), 5.90 (d, J=6.8 Hz, 2H);
(59) .sup.13C-NMR (100 MHz, CDCl.sub.3): δ 150.59, 144.18 (dd, J=8.3, 1.2 Hz), 138.34, 136.49 (t, J=8.7 Hz), 134.80-133.80 (m), 132.88 (ddd, J=20.5, 8.2, 1.7 Hz), 127.58, 126.02-124.89 (m), 122.37 (tt, J=4.0, 2.2 Hz).
(60) ##STR00031##
(61) Compound C obtained in step (1) (8.61 g, 20 mmol) and 100 mL of dichloromethane (DCM) were sequentially added to a 250 mL three-necked flask. A mixed solution of compound D (N, N′-carbonyldiimidazole) (4.05 g, 25 mmol) and 100 mL of dichloromethane was added dropwise at room temperature. After the addition, the mixture was reacted at room temperature for 2 h and then filtered with suction. A filter cake was rinsed with dichloromethane to obtain compound E.
(62) Characterization Results of Compound E:
(63) .sup.1H-NMR (400 MHz, CDCl.sub.3): δ 8.40-8.29 (m, 4H), 8.24 (dd, J=7.5, 1.5 Hz, 2H), 8.07 (s, 2H), 7.75 (dd, J=7.4, 1.5 Hz, 2H), 7.32 (t, J=7.5 Hz, 2H);
(64) .sup.13C-NMR (100 MHz, CDCl.sub.3): δ 152.12, 146.42, 145.28 (dd, J=8.3, 1.2 Hz), 143.86-143.01 (m), 137.89 (dd, J=9.1, 1.2 Hz), 137.16, 136.85-136.39 (m), 131.56 (dd, J=7.2, 2.1 Hz), 127.68, 124.96 (tt, J=4.1, 2.1 Hz), 124.49 (dd, J=7.3, 2.1 Hz).
(65) ##STR00032##
(66) Compound E obtained in step (2) (9.13 g, 20 mmol), 1000 mL of ethanol, iron powder (4.3 g, 1 mol), and 100 mL of saturated aqueous ammonium chloride solution were sequentially added into a 250 mL three-necked flask, and heated and refluxed for 5 h. After TLC monitored that the reaction was complete, the reaction solution was filtered, and a filter cake was rinsed with ethyl acetate. After the filtrate was separated, the organic phases were spin-dried to obtain compound F.
(67) Characterization Results of Compound F:
(68) .sup.1H-NMR (400 MHz, CDCl.sub.3): δ 8.48-8.21 (m, 4H), 8.07 (s, 2H), 7.71 (dd, J=7.5, 1.5 Hz, 2H), 7.15 (t, J=7.5 Hz, 2H), 6.76 (dd, J=7.5, 1.5 Hz, 2H), 5.40 (s, 4H);
(69) .sup.13C-NMR (100 MHz, CDCl.sub.3): δ 153.25, 148.28, 145.22 (dd, J=8.4, 1.2 Hz), 144.57-143.89 (m), 138.14 (dd, J=9.1, 1.2 Hz), 137.65-134.89 (m), 130.71, 128.02 (tt, J=4.1, 2.1 Hz), 125.99, 120.25 (dd, J=7.2, 2.1 Hz), 117.22-114.67 (m).
(70) ##STR00033##
(71) In a 1000 mL three-necked flask, compound F obtained in step (3) (7.92 g, 20 mmol) was dissolved in 32 mL of acetic acid, and copper powder (2 g) was added, stirred, and cooled to 5° C. Isoamyl nitrite (7.8 g, 66 mmol) was dissolved in 16 mL of acetic acid and slowly added dropwise to the system. After the dropwise addition, the mixture was stirred at room temperature. After TLC monitored that the reaction was complete, the reaction solution was separated, and the organic phases were washed once with an aqueous sodium carbonate solution, dried with anhydrous sodium sulfate, spin-dried, and subjected to column chromatography (the eluent was dichloromethane/petroleum ether) to obtain compound G.
(72) Characterization Results of Compound G:
(73) .sup.1H-NMR (400 MHz, CDCl.sub.3): δ 8.81 (dd, J=7.5, 1.5 Hz, 2H), 8.67 (d, J=7.5 Hz, 2H), 8.43 (d, J=7.5 Hz, 2H), 7.93 (dd, J=7.5, 1.5 Hz, 2H), 7.62 (t, J=7.5 Hz, 2H);
(74) .sup.13C-NMR (100 MHz, CDCl.sub.3): δ 154.48, 146.82, 141.73 (d, J=8.3 Hz), 138.34-136.90 (m), 134.74 (dd, J=6.5, 1.2 Hz), 126.82 (dd, J=7.0, 2.1 Hz), 125.32-123.19 (m), 116.42, 114.79-113.29 (m).
(75) ##STR00034##
(76) In an Ar atmosphere, zinc powder (1.6 g, 24 mmol) and 40 mL of tetrahydrofuran (THF) were added to a three-necked flask equipped with a magnetic stirrer. The mixture was cooled to −5° C., TiCl.sub.4 (1.3 mL, 12 mmol) was slowly added with a syringe, and the system was kept below 10° C. The suspended mixture was heated to room temperature and stirred for 0.5 h and then heated to reflux for 2.5 h. Compound G obtained in step (4) (7.25 g, 20 mmol) and compound H (3.72 g, 20 mmol) were dissolved in 15 mL of THF and then slowly added dropwise to the suspended mixture. After the addition, the reaction mixture was heated to reflux until the carbonyl compound was consumed (monitored through thin-layer chromatography (TLC)) (about 14 h). The reaction was cooled, quenched with 10% aqueous K.sub.2CO.sub.3 solution, and extracted with CH.sub.2Cl.sub.2. The organic layer was collected and concentrated, and the crude matter was purified through flash chromatography to obtain the target product M1.
(77) Characterization Results of the Organic Compound M1:
(78) .sup.1H-NMR (400 MHz, CDCl.sub.3): δ 8.77 (dd, J=7.5, 1.5 Hz, 2H), 8.75 (d, J=7.5 Hz, 2H), 8.70 (d, J=7.5 Hz, 2H), 8.66 (s, 2H), 8.50 (d, J=7.5 Hz, 2H), 8.30 (d, J=7.5 Hz, 2H), 7.91 (dd, J=7.5, 1.6 Hz, 2H), 7.63 (t, J=7.5 Hz, 2H);
(79) .sup.13C-NMR (100 MHz, CDCl.sub.3): δ 147.62, 146.60-145.21 (m), 143.98-142.99 (m), 142.36, 141.84 (dd, J=9.3, 1.0 Hz), 139.75-138.66 (m), 137.41 (d, J=8.3 Hz), 130.90 (dd, J=6.7, 1.2 Hz), 126.74 (dd, J=7.0, 2.0 Hz), 122.90 (tq, J=3.4, 1.8 Hz), 121.90 (td, J=6.4, 2.0 Hz), 118.13, 115.84-114.87 (m), 114.27.
Example 2
(80) This example provides an organic compound M2 having the following structure:
(81) ##STR00035##
(82) A preparation method for the organic compound M2 includes steps described below.
(83) ##STR00036##
(84) In an Ar atmosphere, zinc powder (1.6 g, 24 mmol) and 40 mL of THF were added to a three-necked flask equipped with a magnetic stirrer. The mixture was cooled to −5° C., TiCl.sub.4 (1.3 mL, 12 mmol) was slowly added with a syringe, and the system was kept below 10° C. The suspended mixture was heated to room temperature and stirred for 0.5 h and then heated to reflux for 2.5 h. Compound G (7.25 g, 20 mmol) whose preparation method was the same as that of Example 1 and compound H-2 (3.69 g, 20 mmol) were dissolved in 15 mL of THF and then slowly added dropwise to the suspended mixture. After the addition, the reaction mixture was heated to reflux until the carbonyl compound was consumed (monitored by thin-layer chromatography (TLC)) (about 14 h). The reaction was cooled, quenched with 10% aqueous K.sub.2CO.sub.3 solution, and extracted with CH.sub.2Cl.sub.2. The organic layer was collected and concentrated, and the crude matter was purified through flash chromatography to obtain the target product M2.
(85) Characterization Results of the Organic Compound M2:
(86) .sup.1H-NMR (400 MHz, CDCl.sub.3): δ 8.77 (dd, J=7.5, 1.5 Hz, 2H), 8.70 (d, J=7.5 Hz, 2H), 8.58-8.53 (m, 4H), 8.31 (d, J=7.5 Hz, 2H), 7.90 (dd, J=7.5, 1.5 Hz, 2H), 7.63 (t, J=7.5 Hz, 2H), 7.46-7.41 (m, 4H);
(87) .sup.13C-NMR (100 MHz, CDCl.sub.3): δ 147.79, 147.78, 147.73, 147.72, 147.65, 147.16, 139.23, 139.16, 138.07, 138.02, 137.44, 137.38, 130.93, 130.92, 130.88, 130.87, 126.77, 126.76, 126.72, 126.70, 122.92, 122.90, 122.89, 122.87, 121.91, 121.90, 121.33, 121.32, 121.27, 121.26, 119.92, 117.40, 115.53.
Example 3
(88) This example provides an organic compound M3 having the following structure:
(89) ##STR00037##
(90) A preparation method for the organic compound M3 includes steps described below.
(91) ##STR00038##
(92) In an Ar atmosphere, zinc powder (1.6 g, 24 mmol) and 40 mL of THF were added to a three-necked flask equipped with a magnetic stirrer. The mixture was cooled to −5° C., TiCl.sub.4 (1.3 mL, 12 mmol) was slowly added with a syringe, and the system was kept below 10° C. The suspended mixture was heated to room temperature and stirred for 0.5 h and then heated to reflux for 2.5 h. Compound G (7.25 g, 20 mmol) whose preparation method was the same as that of Example 1 and compound H-3 (5.69 g, 20 mmol) were dissolved in 15 mL of THF and then slowly added dropwise to the suspended mixture. After the addition, the reaction mixture was heated to reflux until the carbonyl compound was consumed (monitored through thin-layer chromatography (TLC)) (about 14 h). The reaction was cooled, quenched with 10% aqueous K.sub.2CO.sub.3 solution, and extracted with CH.sub.2Cl.sub.2. The organic layer was collected and concentrated, and the crude matter was purified through flash chromatography to obtain the target product M3.
(93) Characterization Results of the Organic Compound M3:
(94) .sup.1H-NMR (400 MHz, CDCl.sub.3): δ 8.77 (dd, J=7.5, 1.5 Hz, 2H), 8.70 (d, J=7.5 Hz, 2H), 8.64 (d, J=7.5 Hz, 2H), 8.31 (d, J=7.5 Hz, 2H), 8.09 (dd, J=7.4, 1.5 Hz, 2H), 7.90 (dd, J=7.5, 1.5 Hz, 2H), 7.74 (td, J=7.4, 1.6 Hz, 2H), 7.67-7.60 (m, 4H), 7.60 (td, J=7.4, 1.5 Hz, 2H), 7.43 (d, J=7.5 Hz, 2H);
(95) .sup.13C-NMR (100 MHz, CDCl.sub.3): δ 147.74, 147.17, 146.68, 146.65, 146.64, 146.61, 146.59, 146.58, 146.55, 144.38, 139.23, 139.16, 137.91, 137.45, 137.39, 134.53, 131.09, 131.08, 131.04, 131.03, 129.99, 129.97, 129.96, 129.93, 129.91, 129.89, 128.69, 128.68, 128.63, 128.62, 128.62, 126.83, 126.81, 126.77, 126.76, 126.64, 126.62, 124.54, 124.53, 124.52, 124.48, 124.46, 124.17, 124.16, 124.14, 124.11, 124.09, 124.08, 123.32, 123.31, 123.30, 123.28, 121.86, 121.84, 121.80, 121.78, 121.75, 121.73, 117.30, 116.35, 116.33, 116.32, 116.29, 116.27, 116.26, 116.23, 116.20, 113.05.
Example 4
(96) This example provides an organic compound M4 having the following structure:
(97) ##STR00039##
(98) A preparation method for the organic compound M4 includes steps described below.
(99) ##STR00040##
(100) In an Ar atmosphere, zinc powder (1.6 g, 24 mmol) and 40 mL of THF were added to a three-necked flask equipped with a magnetic stirrer. The mixture was cooled to −5° C., TiCl.sub.4 (1.3 mL, 12 mmol) was slowly added with a syringe, and the system was kept below 10° C. The suspended mixture was heated to room temperature and stirred for 0.5 h and then heated to reflux for 2.5 h. Compound G (7.25 g, 20 mmol) whose preparation method was the same as that of Example 1 and compound H-4 (3.71 g, 20 mmol) were dissolved in 15 mL of THF and then slowly added dropwise to the suspended mixture. After the addition, the reaction mixture was heated to reflux until the carbonyl compound was consumed (monitored through thin-layer chromatography (TLC)) (about 14 h). The reaction was cooled, quenched with 10% aqueous K.sub.2CO.sub.3 solution, and extracted with CH.sub.2Cl.sub.2. The organic layer was collected and concentrated, and the crude matter was purified through flash chromatography to obtain the target product M4.
(101) Characterization Results of the Organic Compound M4:
(102) .sup.1H-NMR (400 MHz, CDCl.sub.3): δ 8.77 (dd, J=7.5, 1.5 Hz, 2H), 8.70 (d, J=7.5 Hz, 2H), 8.30 (d, J=7.5 Hz, 2H), 8.16 (s, 2H), 7.91 (dd, J=7.5, 1.6 Hz, 2H), 7.63 (t, J=7.5 Hz, 2H), 7.39-7.29 (m, 3H), 7.31-7.24 (m, 2H);
(103) .sup.13C-NMR (100 MHz, CDCl.sub.3): δ 163.68, 163.40, 150.56, 147.62, 139.23, 139.16, 139.01, 137.44, 137.38, 133.64, 130.93, 130.92, 130.88, 130.87, 129.59, 129.58, 129.57, 129.56, 128.16, 126.77, 126.76, 126.72, 126.70, 123.64, 123.62, 123.58, 123.56, 123.02, 122.93, 122.92, 122.90, 122.89, 122.87, 121.91, 121.90, 121.86, 121.84, 118.13, 115.33, 115.29.
(104) The following are several examples of applications of the organic compounds of the present disclosure in OLED elements.
Application Example 1
(105) This application example provides an OLED device. The OLED device includes a substrate, an indium tin oxide (ITO) anode with a thickness of 15 nm, a hole injection layer with a thickness of 10 nm, a hole transport layer with a thickness of 110 nm, a light emitting layer with a thickness of 30 nm, a first electron transport layer with a thickness of 30 nm, a second electron transport layer with a thickness of 5 nm, a cathode (a magnesium-silver electrode at a Mg—Ag mass ratio of 9:1) with a thickness of 15 nm, and a capping layer with a thickness of 100 nm.
(106) The OLED Device was Prepared by Steps Described Below.
(107) (1) A glass substrate with a size of 50 mm×50 mm×0.7 mm was cut, sonicated in isopropyl alcohol and deionized water for 30 min separately, and cleaned under ozone for 10 min. The obtained glass substrate having the ITO anode with a thickness of 15 nm was installed onto a vacuum deposition apparatus.
(108) (2) A compound HAT-CN was deposited through vacuum evaporation on the ITO anode layer at a vacuum degree of 2×10.sup.−6 Pa as the hole injection layer with a thickness of 10 nm.
(109) (3) A compound TAPC was deposited through vacuum evaporation on the hole injection layer as the hole transport layer with a thickness of 110 nm.
(110) (4) The light emitting layer with a thickness of 30 nm was co-deposited on the hole transport layer, where the organic compound M1 provided in Example 1 of the present disclosure was used as a host material of the light emitting layer, a compound Ir(piq).sub.2(acac) was used as a doped material of the light emitting layer, and a mass ratio of M1 to the doped material was 9:1.
(111) (5) A compound TPBi was deposited through vacuum evaporation on the light emitting layer as the first electron transport layer with a thickness of 30 nm.
(112) (6) A compound Alq3 was deposited through vacuum evaporation on the first electron transport layer as the second electron transport layer with a thickness of 5 nm.
(113) (7) The magnesium-silver electrode was deposited through vacuum evaporation on the second electron transport layer as the cathode with a thickness of 15 nm.
(114) (8) CBP was deposited through vacuum evaporation on the cathode as a cathode covering layer (the capping layer) with a thickness of 100 nm.
(115) The Compounds Used in the OLED Device have the Following Structures:
(116) ##STR00041## ##STR00042##
Application Example 2
(117) This application example differs from Application Example 1 in that the organic compound M1 in step (4) was replaced with an equal amount of organic compound M2, and other preparation steps were the same.
Application Example 3
(118) This application example differs from Application Example 1 in that the organic compound M1 in step (4) was replaced with an equal amount of organic compound M3, and other preparation steps were the same.
Application Example 4
(119) This application example differs from Application Example 1 in that the organic compound M1 in step (4) was replaced with an equal amount of organic compound M4, and other preparation steps were the same.
Comparative Example 1
(120) This comparative example differs from Application Example 1 in that the organic compound M1 in step (4) was replaced with an equal amount of comparative compound CBP
(121) ##STR00043##
and other preparation steps were the same.
Comparative Example 2
(122) This comparative example differs from Application Example 1 in that the organic compound M1 in step (4) was replaced with an equal amount of comparative compound TCTA
(123) ##STR00044##
and other preparation steps were the same.
Performance Test:
(1) Simulated Calculations of Compounds
(124) An energy level difference between a singlet state and a triplet state of an organic compound may be completed by Guassian 09 software (produced by Guassian Inc.). A specific simulation method of the energy level difference ΔE.sub.ST may be referred to Document J. Chem. Comput., 2013, DOI: 10.1021/ct400415r. The optimization and excitation of a molecular structure may both be completed by a TD-DFT method “B3LYP” and a basic group “6-31g (d)”. The organic compounds M1, M2, M3, and M4 provided by the present disclosure were simulated according to the above-mentioned methods. Results are listed in Table 1.
(125) The glass transition temperature T.sub.g (° C.) of the organic compound was measured by a thermogravimetric (TG) analysis, where a test instrument was Netzsch TG 209, and the organic compound was heated under nitrogen protection at a speed of 10° C..Math.min.sup.−1. Test results are listed in Table 1.
(126) TABLE-US-00001 TABLE 1 HOMO LUMO E.sub.g T.sub.1 T.sub.g Compound (eV) (eV) (eV) (eV) (° C.) M1 −5.69 −2.02 3.67 2.93 113 M2 −5.78 −2.00 3.78 3.01 117 M3 −5.74 −1.96 3.78 2.96 126 M4 −5.64 −2.10 3.54 2.89 112
(127) It can be seen from data in Table 1 that through a special design of the molecular structure, the organic compound of the present disclosure has appropriate HOMO energy level and LUMO energy level and a relatively high triplet energy levels T.sub.1 which reaches 2.89 to 3.01 eV, and can inhabit the transfer of triplet energy from a guest back to a host, so as to confine triplet excitons in a light emitting layer and reduce a driving voltage of the device. Meanwhile, the organic compound has a relatively high glass transition temperature T.sub.g which reaches 112 to 126° C., which proves that the organic compound has good thermal stability and film formability.
(128) (2) Performance Evaluation of OLED Devices
(129) A Keithley 2365A digital nanovoltmeter was used for testing currents of the OLED devices at different voltages, and then the currents were divided by a light emitting area to obtain current densities of the OLED devices at different voltages. A Konicaminolta CS-2000 spectroradiometer was used for testing the brightness and radiant energy flux densities of the OLED devices at different voltages. According to the current densities and the brightness of the OLED devices at different voltages, a working voltage, current efficiency (cd/A), and external quantum efficiency (EQE, %) at the same current density (10 mA/cm.sup.2) were obtained, where V.sub.on denotes a turn-on voltage under the brightness of 1 Cd/m.sup.2. Specific data is listed in Table 2.
(130) TABLE-US-00002 TABLE 2 Host Material of the V.sub.turn-on CE EQE Device Light Emitting Layer (V) (Cd/A) (%) Application M1 3.6 37.8 23.1 Example 1 Application M2 3.5 41.3 25.2 Example 2 Application M3 3.7 39.2 24.3 Example 3 Application M4 3.6 35.9 23.5 Example 4 Comparative CBP 4.2 31.3 19.6 Example 1 Comparative TATC 4.5 29.8 17.9 Example 2
(131) It can be seen from data in Table 2 that compared with a host material CBP or TATC of the light emitting layer in the related art, the organic compounds provided by the present disclosure, as host materials of blue light emitting layers, enable the prepared OLED devices to have lower turn-on voltages (which decrease to 3.5 V to 3.7 V), higher current efficiency (which reaches 35.9 Cd/A to 41.3 Cd/A), and higher external quantum efficiency (which reaches 23.1% to 25.2%).
(132) The applicant has stated that although the organic compound, the electroluminescent material and the use thereof in the present disclosure are described through the embodiments described above, the present disclosure is not limited to the processes and steps described above, which means that the implementation of the present disclosure does not necessarily depend on the processes and steps described above. It should be apparent to those skilled in the art that any improvements made to the present disclosure, equivalent replacements of raw materials selected in the present disclosure and addition of adjuvant ingredients thereof, and selections of specific methods, etc., all fall within the protection scope and the disclosed scope of the present disclosure.