Compound used as electron blocking layer for TADF and organic light-emitting device comprising same

Abstract

The present invention relates to: a compound which is used as an electron blocking layer for TADF, the compound being represented by chemical formula 1 below; and an organic light-emitting device comprising same.

Description

Compound used as an electron blocking layer for TADF and organic light-emitting device comprising the same

[0001] The present invention relates to a compound used as an electron blocking layer for TADF and an organic light-emitting device comprising the same, and more particularly, to a compound used as an electron blocking layer for TADF, which exhibits the characteristics of a high T1 energy level and a high glass transition temperature, and an organic light-emitting device comprising the same.

[0002] Conventional organic light-emitting diodes (OLEDs) use phosphorescence for all but the blue light due to efficiency issues. Recently, a team led by Professor Adachi of Japan announced a thermally activated delayed fluorescence (TADF) technology utilizing reverse inter-system crossing (RIC) as an alternative to conventional OLEDs. Since then, a material using pure organic materials rather than high-atomic number metals has been developed, and the material has achieved an internal quantum efficiency of 100%, which is not at all inferior to phosphorescence.

[0003] In TADF, the intersystem transition can occur smoothly when the gap between the S1 energy level and the T1 energy level is very small. The fluorescence generated by this intersystem transition in TADF takes relatively long time to stabilize compared to the conventional fluorescence phenomenon, and the energy consumed in the intersystem transition is sourced from the heat energy existing at room temperature, so it has the characteristic of being thermally activated.

[0004] However, conventional TADF has the problem that the lifespan of the device is shortened due to frequent energy transfer caused by the reverse inter-system transition, and a relatively high driving voltage is required because the device must be moved to a higher position than its original position, resulting in a relatively high power consumption.

[0005] Conventionally, n- and p-doping have been used in the electron and hole transport layers to lower the operating voltage. While this allows for high charge mobility or conductivity and low resistance dissipation for low-voltage operation, it requires the introduction of hole and electron blocking layers to prevent the movement of dopant-diffused electrons to the light-emitting layer. For this reason, it is essential for the electron blocking layer (EBL) for TADF to have a higher T1 value than the compounds used as general electron blocking layers (EBLs).

[0006] In other words, it is time to make efforts to develop compounds that can be used as electron blocking layers for TADF.

[0007] In order to solve the above problems, the present invention aims to provide a compound used as an electron blocking layer for TADF, which exhibits the characteristics of a high T1 energy level and a high glass transition temperature, and an organic light-emitting device including the compound.

[0008] In order to solve the above-mentioned problem, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formula 1.

[0009] [Chemical Formula 1]

[0010]

[0011] In the above chemical formula 1, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R1, R2, R3, and R4 is included, wherein R1 and R2 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R3 and R4 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0012] In order to solve the above-mentioned problems, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formulas.

[0013]

[0014] In order to solve the above-mentioned problem, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formula 2.

[0015] [Chemical Formula 2]

[0016]

[0017] In the above chemical formula 2, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R5, R6, R7, and R8 is included, wherein R5 and R6 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R7 and R8 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0018] In order to solve the above-mentioned problems, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formulas.

[0019]

[0020] In order to solve the above-mentioned problem, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formula 3.

[0021] [Chemical Formula 3]

[0022]

[0023] In the above chemical formula 3, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R9, R10, R11, and R12 is included, wherein R9 and R10 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R11 and R12 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0024] In order to solve the above-mentioned problems, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formulas.

[0025]

[0026] In order to solve the above-mentioned problem, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formula 4.

[0027] [Chemical Formula 4]

[0028]

[0029] In the above chemical formula 4, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R13, R14, R15, and R16 is included, wherein R13 and R14 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R15 and R16 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0030] In order to solve the above-mentioned problems, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formulas.

[0031]

[0032] In order to solve the above-mentioned problem, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formula 5.

[0033] [Chemical Formula 5]

[0034]

[0035] In the above chemical formula 5, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R17, R18, R19, and R20 is included, wherein R17 and R18 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R19 and R20 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0036] In order to solve the above-mentioned problems, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formulas.

[0037]

[0038] In order to solve the above-mentioned problem, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formula 6.

[0039] [Chemical Formula 6]

[0040]

[0041] In the above chemical formula 6, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R21, R22, R23, and R24 is included, wherein R21 and R22 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R23 and R24 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0042] In order to solve the above-mentioned problems, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formulas.

[0043]

[0044] In order to solve the above-mentioned problem, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formula 7.

[0045] [Chemical Formula 7]

[0046]

[0047] In the above chemical formula 7, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R25, R26, R27, and R28 is included, wherein R25 and R26 are each independently hydrogen, a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a carbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R27 and R28 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0048] In order to solve the above-mentioned problems, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formulas.

[0049]

[0050] In order to solve the above-mentioned problem, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formula 8.

[0051] [Chemical Formula 8]

[0052]

[0053] In the above chemical formula 8, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R29, R30, R31, and R32 is included, wherein R29 and R30 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R31 and R32 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0054] In order to solve the above-mentioned problems, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formulas.

[0055]

[0056] In order to solve the above-mentioned problem, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formula 9.

[0057] [Chemical Formula 9]

[0058]

[0059] In the above chemical formula 9, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R33, R34, R35, and R36 is included, wherein R33 and R34 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R35 and R36 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0060] In order to solve the above-mentioned problem, the present invention provides a compound used as an electron blocking layer for TADF represented by the following chemical formula.

[0061]

[0062] In order to solve the above-mentioned problem, the present invention provides an organic light-emitting device including an electron-blocking layer for TADF, characterized in that the electron-blocking layer includes a compound used as an electron-blocking layer according to the chemical formulas 1 to 9.

[0063] The compound used as an electron blocking layer according to the present invention can form an electron blocking layer having a high T1 energy level and a high glass transition temperature, thereby effectively blocking electron diffusion of a TADF light-emitting layer and exhibiting the effect of high compatibility with other layers of a general OLED device.

[0064] The compound used as an electron blocking layer according to the present invention has a molecular structure in which the HOMO and LUMO are in harmony with the overall right angle and planarity, and the substituents within the molecular structure form a molecular structure in which the connecting portion is induced as a meta connection as possible, thereby exerting the effect of securing high T1 and Tg values.

[0065] FIG. 1 is a cross-sectional view showing the structure of an organic light-emitting device according to one embodiment of the present invention.

[0066] Hereinafter, the present invention will be described in more detail.

[0067] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Before describing the present invention in detail, it should be noted that the terms and words used in this specification and claims described below should not be construed as limited to their conventional or dictionary meanings. Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that various equivalents and modified examples may be substituted for them at the time of filing this application.

[0068]

[0069] Materials or compounds used in electron-blocking layers serve as one of the light-emitting materials in OLED devices. The compound of the present invention is a compound (hereinafter, “electron-blocking compound”) used as an electron-blocking layer disposed on one surface of a thermally activated delayed fluorescence (TADF) light-emitting layer.

[0070] Specifically, TADF has an energy state in which the difference between the S1 energy level and the T1 energy level is very small, less than 0.1 eV. This energy state can cause a reverse inter-system crossing phenomenon in which a triplet exciton existing in the T1 energy level moves toward the S1 energy level. Accordingly, TADF can emit light in a 100% efficient fluorescence manner when the triplet exciton that has moved to the S1 energy level by the reverse inter-system crossing moves to the S0 energy level (ground state) together with the singlet exciton that was previously present in the S1 energy level. Since the above-mentioned intersystem transition frequently occurs in TADF, the lifespan of the device is shortened and a high driving voltage is required (since the S1 energy level is relatively high compared to the T1 energy level, a shift to a higher energy level is required when an intersystem transition occurs). In order to lower the driving voltage, the electron transport layer and hole transport layer are each n-doped or p-doped. However, in this case, the dopant due to doping may diffuse into the light-emitting layer, and an electron-blocking layer is applied to prevent this phenomenon.

[0071] The electron blocking layer arranged on one side of the TADF light-emitting layer corresponds to a layer that performs the function of preventing electrons of the TADF light-emitting layer from moving to another layer adjacent to the light-emitting layer due to doping to lower the driving voltage.

[0072]

[0073] Meanwhile, electron-blocking layer materials significantly impact the performance of OLED devices, and overall OLED device performance can vary significantly depending on how the materials are designed and synthesized. A fundamental requirement for electron-blocking layers in TADF emitting layers is a high T1 energy level (T1 value). It is desirable for compounds used as electron-blocking layers in TADF emitting layers to have a T1 value of 3.0 eV or higher.

[0074] In addition, it is preferable that the compound used as the electron blocking layer for the above TADF has a Tg value of 100°C or higher.

[0075] In order for the compound used as the electron blocking layer for the TADF to exhibit the characteristics of having a high T1 value and a high Tg value, it is desirable to have a molecular structure in which the HOMO (Highest Occupied Molecular Orbital) and the LUMO (Lowest Unoccupied Molecular Orbital) are distributed throughout the molecule in a orthogonal structure and the substituents are connected to each other in a meta structure. However, if the structure is emphasized too much, the planar structure may be broken and the Tg value may be lowered, so a harmony of these is required.

[0076]

[0077] Meanwhile, the electron blocking layer must have high compatibility not only in terms of its own properties, but also in a combined state with the hole injection layer, the light-emitting layer, and the electrode layer, so that the overall efficiency and lifespan of the OLED device must be maintained at a certain level or higher.

[0078]

[0079] In order to satisfy the above requirements, a compound used as an electron blocking layer for TADF of the present invention (hereinafter, electron blocking compound) was derived.

[0080] More specifically, the electron-blocking compound according to the present invention is characterized by having a molecular structure in which the HOMO and LUMO are distributed throughout the molecule in a perpendicular structure while maintaining planarity. In this case, it is preferable that the substituents of the electron-blocking compound are connected to each other in a meta structure.

[0081] Structurally, the present invention is characterized by a compound having a biphenyl-pyridoindole derivative as a parent structure in which a pyrido indole containing an unshared electron pair is connected to the terminal of biphenyl (1,1'-biphen), and the overall molecular structure including HOMO and LUMO is characterized by a harmony of orthogonality and planarity by introducing various substituents. Such a biphenyl-pyridoindole derivative parent structure imparts molecular stereotacticity to the entire electron-blocking compound, and can prevent the flow of electrons from being blocked in the overall molecular structure, and the electron-blocking compound of the present invention has aromatic characteristics.

[0082]

[0083] Meanwhile, the electron blocking compound according to the present invention can make the structure in which hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, hydrogen and an aromatic derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and a phenylcarbazole derivative, or a carbazole derivative and an aromatic derivative are linked to each other in a meta structure to combine a biphenyl-pyridoindole derivative, more morphologically stable, and can also significantly improve the T1 value and the Tg value.

[0084] In addition, the electron blocking compound according to the present invention implements a DA structure by connecting carbazole derivatives, which are relatively rigid structures as counterparts, so that the HOMO and LUMO are distributed throughout the molecule in a perpendicular structure while the substituents within the structure can connect to each other in a meta structure, thereby harmonizing the overall molecular structure of the compound to maintain an appropriate planar structure.

[0085]

[0086] Specifically, the electron blocking compound according to the present invention has a structure represented by the following chemical formulas 1 to 9:

[0087]

[0088] [Chemical Formula 1]

[0089]

[0090] In the above chemical formula 1, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R1, R2, R3, and R4 is included, wherein R1 and R2 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R3 and R4 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0091]

[0092] [Chemical Formula 2]

[0093]

[0094] In the above chemical formula 2, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R5, R6, R7, and R8 is included, wherein R5 and R6 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R7 and R8 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0095]

[0096] [Chemical Formula 3]

[0097]

[0098] In the above chemical formula 3, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R9, R10, R11, and R12 is included, wherein R9 and R10 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R11 and R12 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0099]

[0100] [Chemical Formula 4]

[0101]

[0102] In the above chemical formula 4, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R13, R14, R15, and R16 is included, wherein R13 and R14 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R15 and R16 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0103]

[0104] [Chemical Formula 5]

[0105]

[0106] In the above chemical formula 5, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R17, R18, R19, and R20 is included, wherein R17 and R18 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R19 and R20 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0107]

[0108] [Chemical Formula 6]

[0109]

[0110] In the above chemical formula 6, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R21, R22, R23, and R24 is included, wherein R21 and R22 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R23 and R24 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0111]

[0112] [Chemical Formula 7]

[0113]

[0114] In the above chemical formula 7, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R25, R26, R27, and R28 is included, wherein R25 and R26 are each independently hydrogen, a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a carbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R27 and R28 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0115]

[0116] [Chemical Formula 8]

[0117]

[0118] In the above chemical formula 8, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R29, R30, R31, and R32 is included, wherein R29 and R30 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R31 and R32 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0119]

[0120] [Chemical Formula 9]

[0121]

[0122]

[0123] In the above chemical formula 9, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, and at least one of R33, R34, R35, and R36 is included, wherein R33 and R34 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, and R35 and R36 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

[0124]

[0125] In the above chemical formulas 1 to 9, if any one of X, Y, Z, and W is nitrogen, the others are all hydrogen, or if X and Y are nitrogen, Z and W are hydrogen, or if Z and W are nitrogen, X and Y are hydrogen, or if Y and W are nitrogen, X and Z are hydrogen, the following cases are as follows.

[0126]

[0127] The electron blocking compound according to the present invention having the structure of the above chemical formula has a high T1 value and Tg value in electron blocking, thereby blocking electrons in the light-emitting layer from diffusing and moving to an adjacent layer.

[0128] Therefore, the compound having a structure according to the above chemical formula has overall electron blocking properties superior to those of compounds used as conventional electron blocking layers, and can implement an electron blocking layer having high T1 and Tg values, making it suitable for use as an electron blocking layer disposed on one side of a TADF light-emitting layer.

[0129] That is, the present invention provides a compound used as an electron blocking layer for TADF that not only has a high T1 value required for TADF, but also has a high Tg value.

[0130]

[0131] In addition, the electron blocking compound according to embodiments of the present invention is a compound used as an electron blocking layer for TADF, and the electron blocking layer is a layer that performs the function of preventing electrons of the TADF light-emitting layer from moving to an adjacent layer such as a hole transport layer.

[0132]

[0133] The basic requirement of the electron blocking layer of the TADF emitting layer is to have a high T1 value, and thus to block the movement of electrons diffusing from the emitting layer.

[0134] The present invention provides a biphenyl-pyridoindole derivative with conformational stability by combining at least one hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, hydrogen and an aromatic derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and a phenylcarbazole derivative, or a carbazole derivative and an aromatic derivative to a biphenyl-pyridoindole derivative core structure. Specifically, as in the embodiments of the present invention, when hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, hydrogen and an aromatic derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and a phenylcarbazole derivative, or a carbazole derivative and an aromatic derivative are combined in a meta structure around the biphenyl-pyridoindole derivative nucleus, and the HOMO and LUMO are distributed throughout the molecule in a orthogonal structure while having a molecular form that can secure planarity, it can have advantages in terms of the T1 value and the Tg value.

[0135]

[0136] The compounds according to the above embodiments of the present invention can be represented by the following chemical formula.

[0137]

[0138]

[0139]

[0140]

[0141]

[0142]

[0143]

[0144]

[0145]

[0146]

[0147]

[0148] In such a structure, the structure has a structure capable of maximizing the T1 value and the Tg value by having at least one hydrogen, carbazole derivative, hydrogen and carbazole derivative, hydrogen and biphenylcarbazole derivative, hydrogen and pyridoindole derivative, hydrogen and pyrrolodipyridine derivative, hydrogen and aromatic derivative, hydrogen and dicarbazolebenzene derivative, hydrogen and phenylcarbazole derivative, or carbazole derivative and aromatic derivative linked in a meta structure around the parent nucleus.

[0149] When at least one of the nuclei surrounding a biphenyl-pyridoindole derivative is hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyrrolodipyridine derivative, hydrogen and an aromatic derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and a phenylcarbazole derivative, or a carbazole derivative and an aromatic derivative, and the molecular structure including the HOMO and the LUMO has a structure in which the orthogonality and planarity are harmonized overall, it can have advantages in terms of the TI value and the Tg value.

[0150]

[0151] organic light-emitting diode

[0152] Hereinafter, the structure and manufacturing method of an organic light-emitting device employing an electron blocking compound according to the present invention will be described.

[0153]

[0154] The organic light-emitting device according to the present invention can adopt the structure of a conventional light-emitting device, and the structure can be changed as needed. Basically, the organic light-emitting device has a structure including an organic film (light-emitting layer) between a first electrode (anode electrode) and a second electrode (cathode electrode), and may further include a hole injection layer, a hole transport layer, a hole suppression layer, an electron blocking layer, an electron injection layer, or an electron transport layer. To explain the structure of the organic light-emitting device of the present invention, reference is made to FIG. 1.

[0155] Referring to FIG. 1, the organic light-emitting device according to the present invention has a structure including a light-emitting layer (60) between an anode electrode (20) and a cathode electrode (90), and includes a hole injection layer (30) and a hole transport layer (40) between the anode electrode (20) and the light-emitting layer (60), and further includes an electron transport layer (60) and an electron injection layer (80) between the light-emitting layer (60) and the cathode electrode (90). The organic light-emitting device according to the present invention includes an electron blocking layer (50) between the hole transport layer (40) and the light-emitting layer (60) in order to prevent electrons of the light-emitting layer (60) from flowing into the hole transport layer (40), etc., thereby reducing light-emitting efficiency and lifespan.

[0156] Meanwhile, the organic light-emitting device of FIG. 1 according to one embodiment of the present invention is manufactured through the following process, which is merely illustrative and is not limited to this method.

[0157] First, an anode electrode material is coated on the upper portion of the substrate (10) to form an anode electrode (20). Here, the substrate (10) may be a substrate generally used in this field, and in particular, a glass substrate or a transparent plastic substrate having excellent transparency, surface smoothness, ease of handling, and waterproofing is preferable. In addition, the anode electrode material formed on the substrate may be transparent and has excellent conductivity, such as indium tin oxide (ITO), tin oxide (SnO2), zinc oxide (ZnO), etc., but is not limited thereto.

[0158] A hole injection layer (HIL) (30) is selectively formed on the upper portion of the anode electrode (20). At this time, the hole injection layer is formed through a conventional method such as vacuum deposition or spin coating. The material for the hole injection layer is not particularly limited, but CuPc (copper phthalocyanine) or IDE 406 (Idemitsu Kosan) can be used.

[0159] Next, the hole transport layer (HTL) (40) is formed on the hole injection layer (30) through a conventional method such as vacuum deposition or spin coating. As the material for the hole transport layer, N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4'-diamine (NPB), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine (TPD), N,N'-di(naphthalen-1-yl)-N,N'-diphenylbenzidine, N,N'-di(naphthalen-1-yl)-N,N'-diphenyl-benzidine:α-NPD) and the like can be used, but are not limited thereto.

[0160] Next, an electron blocking layer (EBL) (50) that prevents electrons of the light emitting layer (EML) (60) from moving from the light emitting layer (EML) (60) to the hole transport layer (HTL) (40) may be formed on top of the hole transport layer (HTL) (40), and in the embodiment of the present invention, an electron blocking compound according to the chemical formulas described above is included as a material for the electron blocking layer (EBL) (50).

[0161] Next, an emission layer (EML) (60) is formed on the electron blocking layer (EBL) (50). The emission layer forming material may include at least one selected from among phosphorescent host compounds as an emission host material, and may have a single layer or a multilayer structure of two or more layers. The emission layer (EML) according to one embodiment of the present invention may have a multilayer structure including a host emission layer and an emitter emission layer. At this time, the compound of the present invention may be included alone or may be included in a mixture with other compounds known in the art, for example, a blue emission dopant (iridium compound such as FIrppy or FIrpic). The phosphorescent host compound of the emission layer (60) may be included in a range of 1 to 95 wt% based on the total weight of the material constituting the emission layer (60).

[0162] The above phosphorescent host compound can be formed by a vacuum deposition method, and can also be deposited through a wet process such as spin coating, or laser ion induced thermal imaging (LITI) can be used.

[0163] Optionally, a hole blocking layer (HBL) may be formed on the upper portion of the light-emitting layer (60) to prevent excitons formed in the light-emitting material from moving to the electron transport layer or holes from moving to the electron transport layer (70). The material for the hole blocking layer is not particularly limited, but a phenanthroline-based compound (e.g., BCP) or the like may be used. This may be formed through a vacuum deposition method or a spin coating method.

[0164] Additionally, an electron transport layer (ETL) (70) may be formed on the light-emitting layer (60), and a vacuum deposition method or a spin coating method may be used. The material for the electron transport layer is not particularly limited, but TBPI and an aluminum complex (e.g., Alq3(tris(8-quinolinolato)-aluminum)) may be used.

[0165] An electron injection layer (EIL) (80) can be formed on top of the electron transport layer (70) using a method such as vacuum deposition or spin coating, and the material for the electron injection layer (80) is not particularly limited, but materials such as LiF, NaCl, and CsF can be used.

[0166] Next, a cathode electrode (90) is formed on top of the electron injection layer (80) through vacuum deposition, thereby completing the light-emitting element. Here, lithium (Li), magnesium (Mg), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag), etc. are used as the cathode metal.

[0167] In addition, the organic light-emitting device according to the present invention has a laminated structure as shown in Fig. 1, and, if necessary, it is also possible to further form one or two intermediate layers, such as a hole-blocking layer. In addition, the thickness of each layer of the light-emitting device can be determined as necessary within a range generally used in this field.

[0168] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples.

[0169]

[0170] Synthesis example of electron blocking compound according to the present invention

[0171]

[0172] Synthesis Example 1

[0173]

[0174] Synthesis of 5-(3'-bromo-5-(5H-pyrido[4,3-b]indol-5-yl)-[1,1'-biphenyl]-3-yl)-5H-pyrido[3,2-b]indole

[0175] Add 34.5 g (0.205 mol) of 5H-pyrido[3,2-b]indole and 21.2 g (0.220 mol) of sodium tert-butoxide to 800 mL of toluene and stir for 30 minutes to dissolve. Then, add 48.5 g (0.100 mol) of 3'-bromo-3,5-diiodo-1,1'-biphenyl and stir at 50°C for 40 minutes. Add a solution of 20.4 g (0.070 mmol) of Pd(dba) dissolved in 2.42 mL (10 mmol) of tri-tert-butylphosphine to the reaction solution and react under reflux for 12 hours. After confirming the completion of the reaction, the mixture was cooled to room temperature, filtered through silica, and the filtrate was distilled under reduced pressure. The resulting residue was subjected to silica gel chromatography using a 10:1 mixed solution of MC and EA as the eluent, to obtain 47.1 g (83.3%) of the target compound, 5-(3'-bromo-5-(5H-pyrido[4,3-b]indol-5-yl)-[1,1'-biphenyl]-3-yl)-5H-pyrido[3,2-b]indole.

[0176]

[0177] Synthesis Example 2

[0178]

[0179] Synthesis of 5-(2,3'-dibromo-[1,1'-biphenyl]-4-yl)-5H-pyrido[3,2-b]indole

[0180] Add 17.7 g (0.105 mol) of 5H-pyrido[3,2-b]indole and 11.6 g (0.120 mol) of sodium tert-butoxide to 800 mL of toluene and stir for 30 minutes to dissolve. Then, add 43.7 g (0.100 mol) of 2,3'-dibromo-4-iodo-1,1'-biphenyl and stir at 50°C for 40 minutes. Add a solution of 20.2 g (0.035 mmol) of Pd(dba) dissolved in 1.21 mL (5 mmol) of tri-tert-butylphosphine to the reaction solution and react under reflux for 10 hours. After confirming the completion of the reaction, the mixture was cooled to room temperature, filtered through silica, and the filtrate was distilled under reduced pressure. The resulting residue was subjected to silica gel chromatography using a 5:1 mixed solution of EA and MeOH as the eluent, to obtain 29.7 g (62.2%) of the target compound, 5-(2,3'-dibromo-[1,1'-biphenyl]-4-yl)-5H-pyrido[3,2-b]indole.

[0181]

[0182] Synthesis Example 3

[0183]

[0184] Synthesis of 5-(3'-(9H-carbazol-9-yl)-5-(5H-pyrido[4,3-b]indol-5-yl)-[1,1'-biphenyl]-3-yl)-5H-pyrido[3,2-b]indole

[0185] Add 1.76 g (10.5 mmol) of 9H-carbazole and 1.16 g (12.0 mol) of sodium tert-butoxide to 200 mL of toluene and stir for 30 minutes to dissolve. Then, add 5.65 g (10.0 mol) of 5-(3'-bromo-5-(5H-pyrido[4,3-b]indol-5-yl)-[1,1'-biphenyl]-3-yl)-5H-pyrido[3,2-b]indole and stir at 50°C for 40 minutes. Add a solution of 20.02 g (0.0035 mmol) of Pd(dba) dissolved in 0.6 mL (2.5 mmol) of tri-tert-butylphosphine to the reaction solution and react under reflux for 10 hours. After confirming the completion of the reaction, the mixture was cooled to room temperature, filtered through silica, and the filtrate was distilled under reduced pressure. The resulting residue was subjected to silica gel chromatography using a mixture of MC and MeOH 8:1 as the eluent, and purified by sublimation to obtain 4.05 g (62.2%) of the target compound 5-(3'-(9H-carbazol-9-yl)-5-(5H-pyrido[4,3-b]indol-5-yl)-[1,1'-biphenyl]-3-yl)-5H-pyrido[3,2-b]indole.

[0186]

[0187] Synthesis Example 4

[0188]

[0189] Synthesis of 5-(2,3'-di(9H-carbazol-9-yl)-[1,1'-biphenyl]-4-yl)-5H-pyrido[3,2-b]indole

[0190] Add 3.52 g (21.0 mmol) of 9H-carbazole and 2.32 g (24.0 mol) of sodium tert-butoxide to 300 mL of toluene and stir for 30 minutes to dissolve. Then, add 5.65 g (10.0 mol) of 5-(2,3'-dibromo-[1,1'-biphenyl]-4-yl)-5H-pyrido[3,2-b]indole and stir at 50°C for 40 minutes. Add a solution of 20.04 g (0.0079 mmol) of Pd(dba) dissolved in 0.8 mL (3.3 mmol) of tri-tert-butylphosphine to the reaction solution and react under reflux for 10 hours. After confirming the completion of the reaction, the mixture was cooled to room temperature, filtered through silica, and the filtrate was distilled under reduced pressure. The resulting residue was subjected to silica gel chromatography using a 7:1 mixed solution of MC and MeOH as the eluent, and purified by sublimation to obtain 4.47 g (68.6%) of the target compound 5-(2,3'-di(9H-carbazol-9-yl)-[1,1'-biphenyl]-4-yl)-5H-pyrido[3,2-b]indole.

[0191]

[0192] Synthesis Example 5

[0193]

[0194] Synthesis of 5-(2,4''-di(9H-carbazol-9-yl)-[1,1':3',1''-terphenyl]-4-yl)-5H-pyrido[3,2-b]indole

[0195] Add 1.76 g (10.5 mmol) of 9H-carbazole and 1.16 g (12.0 mol) of sodium tert-butoxide to 200 mL of toluene and stir for 30 minutes to dissolve. Then, add 6.40 g (10.0 mol) of 5-(4''-bromo-2-(9H-carbazol-9-yl)-[1,1':3',1''-terphenyl]-4-yl)-5H-pyrido[3,2-b]indole and stir at 50°C for 40 minutes. Add a solution of 20.02 g (0.0035 mmol) of Pd(dba) dissolved in 0.6 mL (2.5 mmol) of tri-tert-butylphosphine to the reaction solution and react under reflux for 10 hours. After confirming the completion of the reaction, the mixture was cooled to room temperature, filtered through silica, and the filtrate was distilled under reduced pressure. The resulting residue was subjected to silica gel chromatography using a mixture of MC and MeOH 8:1 as the eluent, and purified by sublimation to obtain 4.70 g (64.7%) of the target compound 5-(2,4''-di(9H-carbazol-9-yl)-[1,1':3',1''-terphenyl]-4-yl)-5H-pyrido[3,2-b]indole.

[0196]

[0197] Synthesis Example 6

[0198]

[0199] Synthesis of 9-(3'',5''-di(9H-carbazol-9-yl)-[1,1':3',1''-terphenyl]-4-yl)-9H-pyrido[2,3-b]indole

[0200] Add 1.77 g (10.5 mmol) of 9H-pyrido[2,3-b]indole and 1.16 g (12.0 mol) of sodium tert-butoxide to 200 mL of toluene and stir for 30 minutes to dissolve. Then, add 6.40 g (10.0 mol) of 9,9'-(4''-bromo-[1,1':3',1''-terphenyl]-3,5-diyl)bis(9H-carbazole) and stir at 50°C for 40 minutes. Add a solution of 20.02 g (0.0035 mmol) of Pd(dba) dissolved in 0.6 mL (2.5 mmol) of tri-tert-butylphosphine to the reaction solution and react under reflux for 10 hours. After confirming the completion of the reaction, the mixture was cooled to room temperature, filtered through silica, and the filtrate was distilled under reduced pressure. The resulting residue was subjected to silica gel chromatography using a 9:1 mixed solution of MC and MeOH as the eluent, and purified by sublimation to obtain 4.92 g (67.7%) of the target compound 9-(3'',5''-di(9H-carbazol-9-yl)-[1,1':3',1''-terphenyl]-4-yl)-9H-pyrido[2,3-b]indole.

[0201]

[0202] Synthesis Example 7

[0203]

[0204] Synthesis of 9-(3'',5-di(9H-carbazol-9-yl)-[1,1':3',1''-terphenyl]-2-yl)-9H-pyrrolo[2,3-b:5,4-c']dipyridine

[0205] Add 3.52 g (21.0 mmol) of 9H-carbazole and 2.32 g (24.0 mol) of sodium tert-butoxide to 300 mL of toluene and stir for 30 minutes to dissolve. Then, add 5.55 g (10.0 mol) of 9-(3'',5-dibromo-[1,1':3',1''-terphenyl]-2-yl)-9H-pyrrolo[2,3-b:5,4-c']dipyridine and stir at 50°C for 40 minutes. Add a solution of 20.04 g (0.0079 mmol) of Pd(dba) dissolved in 0.8 mL (3.3 mmol) of tri-tert-butylphosphine to the reaction solution and react under reflux for 12 hours. After confirming the completion of the reaction, the mixture was cooled to room temperature, filtered through silica, and the filtrate was distilled under reduced pressure. The resulting residue was subjected to silica gel chromatography using a 5:1 mixed solution of MC and MeOH as the eluent, and purified by sublimation to obtain 4.44 g (60.9%) of the target compound 9-(3'',5-di(9H-carbazol-9-yl)-[1,1':3',1''-terphenyl]-2-yl)-9H-pyrrolo[2,3-b:5,4-c']dipyridine.

[0206]

[0207] Synthesis Example 8

[0208]

[0209] Synthesis of 9-(3''',4'-di(9H-carbazol-9-yl)-[1,1':3',1'':3'',1'''-quaterphenyl]-2-yl)-9H-pyrido[2,3-b]indole

[0210] Add 3.52 g (21.0 mmol) of 9H-carbazole and 2.32 g (24.0 mol) of sodium tert-butoxide to 300 mL of toluene and stir for 30 minutes to dissolve. Then, add 6.30 g (10.0 mol) of 9-(3''',4'-dibromo-[1,1':3',1'':3'',1'''-quaterphenyl]-2-yl)-9H-pyrido[2,3-b]indole and stir at 50°C for 40 minutes. Add a solution of 20.04 g (0.0079 mmol) of Pd(dba) dissolved in 0.8 mL (3.3 mmol) of tri-tert-butylphosphine to the reaction solution and react under reflux for 10 hours. After confirming the completion of the reaction, the mixture was cooled to room temperature, filtered through silica, and the filtrate was distilled under reduced pressure. The residue obtained was subjected to silica gel chromatography using a 3:1 mixed solution of MC and EA as the eluent, and purified by sublimation to obtain 4.00 g (45.8%) of the target compound 9-(3''',4'-di(9H-carbazol-9-yl)-[1,1':3',1'':3'',1'''-quaterphenyl]-2-yl)-9H-pyrido[2,3-b]indole.

[0211]

[0212] Synthesis Example 9

[0213]

[0214] Synthesis of 9-(3,6''-di(9H-carbazol-9-yl)-[1,1':2',1'':3'',1'''-quaterphenyl]-2'''-yl)-9H-pyrido[2,3-b]indole

[0215] Add 3.52 g (21.0 mmol) of 9H-carbazole and 2.32 g (24.0 mol) of sodium tert-butoxide to 300 mL of toluene and stir for 30 minutes to dissolve. Then, add 6.30 g (10.0 mol) of 9-(3''',4'-dibromo-[1,1':3',1'':3'',1'''-quaterphenyl]-2-yl)-9H-pyrido[2,3-b]indole and stir at 50°C for 40 minutes. Add a solution of 20.04 g (0.0079 mmol) of Pd(dba) dissolved in 0.8 mL (3.3 mmol) of tri-tert-butylphosphine to the reaction solution and react under reflux for 12 hours. After confirming the completion of the reaction, the mixture was cooled to room temperature, filtered through silica, and the filtrate was distilled under reduced pressure. The residue obtained was first subjected to silica gel chromatography using a 3:1 mixed solution of MC and EA as the eluent, and secondly to silica gel chromatography using a 2:1 mixed solution of MC: MeOH, and then purified by sublimation to obtain 3.07 g (38.2%) of the target compound 9-(3,6''-di(9H-carbazol-9-yl)-[1,1':2',1'':3'',1'''-quaterphenyl]-2'''-yl)-9H-pyrido[2,3-b]indole.

[0216]

[0217] Synthesis Example 10

[0218]

[0219] Synthesis of 9-(3'''',4''-di(9H-carbazol-9-yl)-[1,1':2',1'':3'',1''':3''',1''''-quinquephenyl]-3-yl)-9H-pyrido[2,3-b]indole

[0220] Add 7.16 g (0.01 mol) of 9-(3'''-bromo-4''-(9H-carbazol-9-yl)-[1,1':2',1'':3'',1'''-quaterphenyl]-3-yl)-9H-pyrido[2,3-b]indole, 4.31 g (0.015 mol) of (3-(9H-carbazol-9-yl)phenyl)boronic acid, and 2.76 g (0.02 mol) of potassium carbonate to 80 mL of toluene, 20 mL of ethanol, and 20 mL of H2O, and stir for 1 hour. Then, add 40.64 g (0.6 mmol) of Pd(PPh3) and react by refluxing and stirring at 110℃ for 10 hours. After confirming the completion of the reaction, extract with MC. The MC layer was dehydrated and filtered with anhydrous MgSO, and the filtrate was distilled under reduced pressure. The residue obtained was subjected to silica gel chromatography using a 7:1 mixed solution of MC and EA as the eluent, obtaining 3.87 g (44.0%). The obtained compound was purified by sublimation to obtain 3.20 g (36.2.1%) of the target compound 9-(3'''',4''-di(9H-carbazol-9-yl)-[1,1':2',1'':3'',1''':3''',1''''-quinquephenyl]-3-yl)-9H-pyrido[2,3-b]indole.

[0221]

[0222] Synthesis Example 11

[0223]

[0224] Synthesis of 9-(3'',5''-di(9H-carbazol-9-yl)-[1,1':3',1''-terphenyl]-2-yl)-9H-pyrido[2,3-b]indole

[0225] Add 3.52 g (21.0 mmol) of 9H-carbazole and 2.32 g (24.0 mol) of sodium tert-butoxide to 300 mL of toluene and stir for 30 minutes to dissolve. Then, add 5.54 g (10.0 mol) of 9-(3'',5''-dibromo-[1,1':3',1''-terphenyl]-2-yl)-9H-pyrido[2,3-b]indole and stir at 50°C for 40 minutes. Add a solution of 20.04 g (0.0079 mmol) of Pd(dba) dissolved in 0.8 mL (3.3 mmol) of tri-tert-butylphosphine to the reaction solution and react under reflux for 10 hours. After confirming the completion of the reaction, the mixture was cooled to room temperature, filtered through silica, and the filtrate was distilled under reduced pressure. The residue obtained was subjected to silica gel chromatography using a 1:1 mixed solution of MC and EA as the eluent, and then purified by sublimation to obtain 2.33 g (32.1%) of the target compound 9-(3'',5''-di(9H-carbazol-9-yl)-[1,1':3',1''-terphenyl]-2-yl)-9H-pyrido[2,3-b]indole.

[0226]

[0227] Synthesis Example 12

[0228]

[0229] Synthesis of 9-((1'R)-3,5'-di(9H-carbazol-9-yl)-1',6'-dihydro-[1,1':2',1'':3'',1'''-quaterphenyl]-2'''-yl)-9H-pyrido[2,3-b]indole

[0230] 6.42 g (0.01 mol) of 9-((2''S)-2''-bromo-4''-(9H-carbazol-9-yl)-2'',3''-dihydro-[1,1':3',1''-terphenyl]-2-yl)-9H-pyrido[2,3-b]indole, 4.31 g (0.015 mol) of (3-(9H-carbazol-9-yl)phenyl)boronic acid, and 2.76 g (0.02 mol) of potassium carbonate were added to 100 mL of toluene, 25 mL of ethanol, and 25 mL of H2O, stirred for 1 hour, then 40.64 g (0.6 mmol) of Pd(PPh3) were added, and the mixture was refluxed and stirred at 110°C for 12 hours to react. After confirming the completion of the reaction, extract with MC. The MC layer was dehydrated and filtered with anhydrous MgSO, and the filtrate was distilled under reduced pressure. The residue obtained was subjected to silica gel chromatography using a 5:1 mixed solution of MC and EA as the eluent. The obtained compound was purified by sublimation to obtain 2.70 g (33.6%) of the target compound, 9-((1'R)-3,5'-di(9H-carbazol-9-yl)-1',6'-dihydro-[1,1':2',1'':3'',1'''-quaterphenyl]-2'''-yl)-9H-pyrido[2,3-b]indole.

[0231]

[0232] Synthesis Example 13

[0233]

[0234] Synthesis of 9-(2''',6''-di(9H-carbazol-9-yl)-[1,1':3',1'':3'',1'''-quaterphenyl]-3-yl)-9H-pyrido[2,3-b]indole

[0235] 9,9'-(3''-bromo-[1,1':3',1''-terphenyl]-2,4'-diyl)bis(9H-carbazole) 6.40 g (0.01 mol), (3-(3-(9H-pyrido[2,3-b]indol-9-yl)phenyl)boronic acid 4.32 g (0.015 mol) and potassium carbonate 2.76 g (0.02 mol) were added to 100 mL of toluene, 25 mL of ethanol and 25 mL of H2O and stirred for 1 hour. Then, 40.64 g (0.6 mmol) of Pd(PPh3) was added and stirred under reflux at 110°C for 12 hours to react. After confirming the completion of the reaction, extract with MC. The MC layer was dehydrated and filtered with anhydrous MgSO, and the filtrate was distilled under reduced pressure to obtain a residue obtained by mixing MC and EA 10:1. The compound obtained by silica gel chromatography with the eluent was purified by sublimation to obtain 2.28 g (28.4%) of the target compound 9-(2''',6''-di(9H-carbazol-9-yl)-[1,1':3',1'':3'',1'''-quaterphenyl]-3-yl)-9H-pyrido[2,3-b]indole.

[0236]

[0237] Synthesis Example 14

[0238]

[0239] Synthesis of 9,9'-(2''-(9H-carbazol-9-yl)-[1,1':2',1''-terphenyl]-3,4-diyl)bis(9H-pyrido[2,3-b]indole)

[0240] 4.89 g (0.01 mol) of 9,9'-(4-bromo-1,2-phenylene)bis(9H-pyrido[2,3-b]indole), 5.45 g (0.015 mol) of (2'-(9H-carbazol-9-yl)-[1,1'-biphenyl]-2-yl)boronic acid, and 2.76 g (0.02 mol) of potassium carbonate were added to 150 mL of toluene, 70 mL of ethanol, and 25 mL of H2O, stirred for 1 hour, then 40.64 g (0.6 mmol) of Pd(PPh3) were added, and the mixture was refluxed and stirred at 115°C for 24 hours to react. After confirming the completion of the reaction, extract with MC. The MC layer was dehydrated and filtered with anhydrous MgSO, and the filtrate was distilled under reduced pressure. The residue obtained was subjected to silica gel chromatography using a 12:1 mixed solution of MC and EA as the eluent. The obtained compound was purified by sublimation to obtain 1.62 g (22.2%) of the target compound, 9,9'-(2''-(9H-carbazol-9-yl)-[1,1':2',1''-terphenyl]-3,4-diyl)bis(9H-pyrido[2,3-b]indole).

[0241]

[0242] Synthesis Example 15

[0243]

[0244] Synthesis of 9,9'-(6'-(2-(9H-carbazol-9-yl)phenyl)-2''-(9H-carbazol-9-yl)-[1,1':2',1''-terphenyl]-3,5-diyl)bis(9H-pyrido[2,3-b]indole)

[0245] Add 6.44 g (0.01 mol) and 10.9 g (0.03 mol) of 9,9'-(2',6'-dibromo-[1,1'-biphenyl]-3,5-diyl)bis(9H-pyrido[2,3-b]indole) and 5.52 g (0.04 mol) of potassium carbonate to 300 mL of toluene, 70 mL of ethanol, and 50 mL of H2O, stir for 1 hour, then add 41.28 g (1.2 mmol) of Pd(PPh3) and react by refluxing and stirring at 110℃ for 24 hours. After confirming the completion of the reaction, extract with excess MC. The MC layer was dehydrated and filtered with anhydrous MgSO, and the filtrate was distilled under reduced pressure. The residue obtained was subjected to silica gel chromatography using a 20:1 mixed solution of MC and EA as the eluent. The obtained compound was purified by sublimation to obtain 2.11 g (21.8%) of the target compound, 9,9'-(6'-(2-(9H-carbazol-9-yl)phenyl)-2''-(9H-carbazol-9-yl)-[1,1':2',1''-terphenyl]-3,5-diyl)bis(9H-pyrido[2,3-b]indole).

[0246]

[0247] Compounds according to the embodiments of the present invention described above can be synthesized by a person skilled in the art with reference to Synthesis Examples 1 to 15.

[0248]

[0249] Experimental results of the electron blocking compounds (compounds 1 to 30) synthesized by Synthetic Examples 1 to 15

[0250]

[0251] Representative physical properties of compounds 1 to 30 (synthetic examples 1 to 15) manufactured in the above synthetic examples were evaluated, and the results are shown in Table 1 below.

[0252]

[0253] PropertiesSinglet EnergyTriplet EnergyHOMOLUMOBand gapTgUnit(eV)(eV)(eV)(eV)(℃)Compound 13.433.145.402.712.69114Compound 23.363.105.472.463.01112Compound 33.193.135.242.572.67114Compound 43.293.105.472.413.06111Compound 53.313.105.342.492.85110Compound 63.333.135.292.502.79115Compound 73.183.105.312.482.83112Compound 83.183.125.282.472.81118 Compound 93.283.115.342.143.20112 Compound 103.313.135.282.432.85116 Compound 113.183.135.322.133.19113 Compound 123.293.135.332.183.15114 Compound 133.253.125.162.242.92112 Compound 143.353.085.382.173.21112 Compound 153.573.125.362.213.15121 Compound 163.263.125.292.193.10120 Compound 173.263.125.292.113.18128 Compound 183.203.125.312.083.23127 Compound 193.373.125.362.163.20112 Compound 203.233.115.232.113.12124 Compound 213.183.125.242.153.09128 Compound 223.383.125.262.083.18106 Compound 233.203.115.362.123.24104 Compound 243.353.125.212.103.11132 Compound 253.193.125.252.083.17130 Compound 263.233.135.302.053.25128 Compound 273.263.125.192.133.08112 Compound 283.183.125.192.103.09130 Compound 293.583.115.342.153.19131 Compound 303.343.125.232,103.13110

[0254] Singlet Energy: Singlet energy in film form. Triplet Energy: Triplet energy in film form, corresponding to the T1 value.

[0255] HOMO, LUMO, and band gap: measured from spectrometry and cyclic voltammetry.

[0256] Tg: Glass transition temperature

[0257]

[0258] As shown in Table 1 above, it can be confirmed that the electron blocking compounds according to the embodiments of the present invention have high T1 values ​​overall and have HOMO energy levels and LUMO energy levels that are advantageous for electron blocking.

[0259] In addition, the above materials have the advantage of being able to be manufactured with a high yield by the synthetic examples described above.

[0260]

[0261] As described above, the best embodiments have been disclosed in the drawings and specifications. The present invention is not limited to the above-described embodiments, and various changes and modifications may be made by those skilled in the art without departing from the spirit of the present invention. The true scope of technical protection of the present invention should be determined by the technical spirit of the appended claims.

Claims

1. A compound used as an electron blocking layer for TADF represented by the following chemical formula 1: [Chemical Formula 1] In the above chemical formula 1, If any one of the above X, Y, Z, and W is nitrogen, the others are all hydrogen, or if the above X and Y are nitrogen, the above Z and W are hydrogen, or if the above Z and W are nitrogen, the above X and Y are hydrogen, or if the above Y and W are nitrogen, the above X and Z are hydrogen, Contains at least one of the above R1, R2, R3, and R4, The above R1 and R2 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, A compound used as an electron blocking layer for TADF, wherein the above R3 and R4 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

2. In claim 1, Compounds used as electron blocking layers for TADF represented by the following chemical formulas:

3. A compound used as an electron blocking layer for TADF represented by the following chemical formula 2: [Chemical Formula 2] In the above chemical formula 2, If any one of the above X, Y, Z, and W is nitrogen, the others are all hydrogen, or if the above X and Y are nitrogen, the above Z and W are hydrogen, or if the above Z and W are nitrogen, the above X and Y are hydrogen, or if the above Y and W are nitrogen, the above X and Z are hydrogen, Contains at least one of the above R5, R6, R7, and R8, The above R5 and R6 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, A compound used as an electron blocking layer for TADF, wherein the above R7 and R8 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

4. In claim 3, Compounds used as electron blocking layers for TADF represented by the following chemical formulas:

5. A compound used as an electron blocking layer for TADF represented by the following chemical formula 3: [Chemical Formula 3] In the above chemical formula 3, If any one of the above X, Y, Z, and W is nitrogen, the others are all hydrogen, or if the above X and Y are nitrogen, the above Z and W are hydrogen, or if the above Z and W are nitrogen, the above X and Y are hydrogen, or if the above Y and W are nitrogen, the above X and Z are hydrogen, Contains at least one of the above R9, R10, R11, and R12, The above R9 and R10 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, A compound used as an electron blocking layer for TADF, wherein the above R11 and R12 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

6. In claim 5, Compounds used as electron blocking layers for TADF represented by the following chemical formulas:

7. A compound used as an electron blocking layer for TADF represented by the following chemical formula 4: [Chemical Formula 4] In the above chemical formula 4, If any one of the above X, Y, Z, and W is nitrogen, the others are all hydrogen, or if the above X and Y are nitrogen, the above Z and W are hydrogen, or if the above Z and W are nitrogen, the above X and Y are hydrogen, or if the above Y and W are nitrogen, the above X and Z are hydrogen, Contains at least one of the above R13, R14, R15, and R16, The above R13 and R14 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, A compound used as an electron blocking layer for TADF, wherein the above R15 and R16 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

8. In claim 7, Compounds used as electron blocking layers for TADF represented by the following chemical formulas:

9. A compound used as an electron blocking layer for TADF represented by the following chemical formula 5: [Chemical Formula 5] In the above chemical formula 5, If any one of the above X, Y, Z, and W is nitrogen, the others are all hydrogen, or if the above X and Y are nitrogen, the above Z and W are hydrogen, or if the above Z and W are nitrogen, the above X and Y are hydrogen, or if the above Y and W are nitrogen, the above X and Z are hydrogen, Contains at least one of the above R17, R18, R19, and R20, The above R17 and R18 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, A compound used as an electron blocking layer for TADF, wherein the above R19 and R20 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

10. In claim 9, Compounds used as electron blocking layers for TADF represented by the following chemical formulas:

11. A compound used as an electron blocking layer for TADF represented by the following chemical formula 6: [Chemical Formula 6] In the above chemical formula 6, If any one of the above X, Y, Z, and W is nitrogen, the others are all hydrogen, or if the above X and Y are nitrogen, the above Z and W are hydrogen, or if the above Z and W are nitrogen, the above X and Y are hydrogen, or if the above Y and W are nitrogen, the above X and Z are hydrogen, Contains at least one of the above R21, R22, R23, and R24, The above R21 and R22 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, A compound used as an electron blocking layer for TADF, wherein the above R23 and R24 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

12. In claim 11, Compounds used as electron blocking layers for TADF represented by the following chemical formulas:

13. A compound used as an electron blocking layer for TADF represented by the following chemical formula 7: [Chemical Formula 7] In the above chemical formula 7, If any one of the above X, Y, Z, and W is nitrogen, the others are all hydrogen, or if the above X and Y are nitrogen, the above Z and W are hydrogen, or if the above Z and W are nitrogen, the above X and Y are hydrogen, or if the above Y and W are nitrogen, the above X and Z are hydrogen, Contains at least one of the above R25, R26, R27, and R28, The above R25 and R26 are each independently hydrogen, a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a carbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, A compound used as an electron blocking layer for TADF, wherein the above R27 and R28 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

14. In claim 13, Compounds used as electron blocking layers for TADF represented by the following chemical formulas:

15. A compound used as an electron blocking layer for TADF represented by the following chemical formula 8: [Chemical Formula 8] In the above chemical formula 8, If any one of the above X, Y, Z, and W is nitrogen, the others are all hydrogen, or if the above X and Y are nitrogen, the above Z and W are hydrogen, or if the above Z and W are nitrogen, the above X and Y are hydrogen, or if the above Y and W are nitrogen, the above X and Z are hydrogen, Contains at least one of the above R29, R30, R31, and R32, The above R29 and R30 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, A compound used as an electron blocking layer for TADF, wherein the above R31 and R32 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

16. In claim 15, Compounds used as electron blocking layers for TADF represented by the following chemical formulas:

17. A compound used as an electron blocking layer for TADF represented by the following chemical formula 9: [Chemical Formula 9] In the above chemical formula 9, If any one of the above X, Y, Z, and W is nitrogen, the others are all hydrogen, or if the above X and Y are nitrogen, the above Z and W are hydrogen, or if the above Z and W are nitrogen, the above X and Y are hydrogen, or if the above Y and W are nitrogen, the above X and Z are hydrogen, Contains at least one of the above R33, R34, R35, and R36, The above R33 and R34 are each independently hydrogen, a carbazole derivative, hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a pyridoindole derivative, hydrogen and a pyrrolodipyridine derivative, or hydrogen and an aromatic derivative, A compound used as an electron blocking layer for TADF, wherein the above R35 and R36 are each independently hydrogen and a carbazole derivative, hydrogen and a biphenylcarbazole derivative, hydrogen and a dicarbazolebenzene derivative, hydrogen and an aromatic derivative, hydrogen and a phenylcarbazole derivative, a carbazole derivative and an aromatic derivative, or hydrogen and an aromatic derivative.

18. In claim 17, A compound used as an electron blocking layer for TADF represented by the following chemical formula:

19. In an organic light-emitting device including an electron blocking layer for TADF, An organic light-emitting device characterized in that the electron-blocking layer comprises a compound used as an electron-blocking layer for TADF according to any one of claims 1 to 18.

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