ORGANOMETALLIC COMPOUND AND ORGANIC LIGHT-ILLUMINATE DIODE WITH THE SAME

Abstract

Organometallic compound selected from a group consisting of compounds 216, 217, 246 and 247:

Description

BACKGROUND Technical area

[0001] The present disclosure relates to an organometallic compound and in particular to an organometallic compound with phosphorescence properties and an organic light-emitting diode with the same. Description of the state of the art

[0002] Since display devices are used in various fields, interest in them is increasing. One such display device is the organic light emission display device using an organic light-emitting diode (OLED), which is developing rapidly.

[0003] When electrical charges are injected into the light-emitting layer of an organic light-emitting diode (OLED), located between a positive and a negative electrode, an electron and a hole in the layer recombine to form an exciton. The exciton's energy is then converted into light, causing the OLED to emit light. Compared to conventional indicator devices, OLEDs can operate at low voltages, consume relatively little power, reproduce excellent colors, and can be used in a variety of applications due to the flexibility of the substrate. Furthermore, the size of an OLED can be freely adjusted.

[0004] EP 3 517 540 A1 concerns organic electroluminescent compounds and devices. SUMMARY

[0005] Organic light-emitting diodes (OLEDs) offer superior viewing angles and contrast ratios compared to liquid crystal displays (LCDs). They are also lightweight and ultra-thin, as OLEDs do not require backlighting. An OLED comprises multiple organic layers sandwiched between a negative electrode (electron injection electrode; cathode) and a positive electrode (hole injection electrode; anode). These layers may include a hole injection layer, a hole transport layer, a hole transport auxiliary layer, an electron barrier layer, a light emission layer, an electron transport layer, and so on.

[0006] In this structure of the organic light-emitting diode, when a voltage is applied across the two electrodes, electrons and holes are injected from the negative and positive electrodes, respectively, into the light-emitting layer, and consequently excitons are generated in the light-emitting layer and then fall to a ground state to emit light.

[0007] Organic materials used in organic light-emitting diodes (OLEDs) can be broadly classified into light-emitting materials and charge-transport materials. The light-emitting material is a key factor determining the luminescence efficiency of the OLED. The luminescent material exhibits high quantum efficiency, excellent electron and hole mobility, and exists uniformly and stably within the light-emitting layer. Light-emitting materials can be further classified based on the color of the light emitted: blue, red, and green. A color-generating material may include a host and dopants to enhance color purity and luminescence efficiency through energy transfer.

[0008] In recent years, there has been a trend towards using phosphorescent materials rather than fluorescent materials for the light-emitting layer. When fluorescent materials are used, singlets (approximately 25% of the excitons generated in the light-emitting layer) are used to emit light, while most triplets (approximately 75% of the excitons generated in the light-emitting layer) are dissipated as heat. However, when phosphorescent materials are used, both singlets and triplets are used to emit light.

[0009] Traditionally, an organometallic compound is used as the phosphor material in organic light-emitting diodes (OLEDs). Ongoing research and development of the phosphor material is necessary to address issues of low efficiency and lifespan.

[0010] Consequently, one purpose of the present invention is to create an organometallic compound capable of reducing the operating voltage and improving efficiency and lifetime, and an organic light-emitting diode with an organic light-emitting layer containing the same.

[0011] The purposes of this disclosure are not limited to the purpose mentioned above. Other purposes and benefits of this disclosure, which are not mentioned, can be understood based on the following descriptions and can be understood more clearly based on exemplary embodiments of this disclosure. Furthermore, it is readily apparent that the purposes and benefits of this disclosure can be achieved using means shown in the claims and combinations thereof.

[0012] To achieve the above purpose, the present disclosure provides an organometallic compound according to claim 1, an organic light-emitting diode in which a light-emitting layer contains the same as doping materials, and an organic light-emitting indicator device comprising the organic light-emitting diode:

[0013] The organometallic compound according to exemplary embodiments of the present disclosure can be used as a doping material of the phosphorescent light emission layer of the organic light-emitting diode, so that the operating voltage of the organic light-emitting diode can be reduced and the efficiency and lifetime characteristics of the organic light-emitting diode can be improved.

[0014] The effects of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned are clearly understood by the person skilled in the art from the following descriptions.

[0015] Naturally, both the preceding general description and the following detailed description of the present disclosure are exemplary and explanatory and are intended to provide a further explanation of the invention concepts as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which are included to provide a further understanding of the revelation and are incorporated into and form part of this application, represent embodiments of the revelation and, together with the description, serve to explain principles of the revelation. Fig. Figure 1 is a cross-sectional view schematically showing an organic light-emitting diode in which a light-emitting layer contains an organometallic compound according to an explanatory embodiment of the present disclosure. Fig.Figure 2 is a cross-sectional view schematically representing an organic light-emitting diode with a tandem structure having two light emission stacks containing an organometallic compound according to an explanatory embodiment of the present disclosure. Fig. Figure 3 is a cross-sectional view schematically representing an organic light-emitting diode with a tandem structure having three light emission stacks containing an organometallic compound according to an explanatory embodiment of the present disclosure. Fig. Figure 4 is a cross-sectional view schematically representing an organic light emission indicator device with an organic light-emitting diode according to an explanatory embodiment of the present disclosure. DETAILED DESCRIPTIONS

[0017] The advantages and features of the present disclosure and methods for achieving these advantages and features will become apparent with reference to exemplary embodiments, which will be described in detail later together with the accompanying drawings. However, the present disclosure is not limited to the exemplary embodiments disclosed below, but can be implemented in various different forms. Consequently, these exemplary embodiments are presented only to complete the present disclosure and to fully convey the scope of protection of the present disclosure to the person skilled in the technical field to which the present disclosure belongs, and the present disclosure is defined only by the scope of protection of the claims.

[0018] A shape, size, ratio, angle, number, etc., disclosed in the drawings illustrating the exemplary embodiments of this disclosure are explanatory and the present disclosure is not limited to them. The same reference numerals refer to the same elements. Furthermore, descriptions and details of well-known steps and elements are omitted for the sake of simplicity. Moreover, numerous specific details are set forth in the following detailed description of this disclosure to ensure a thorough understanding of it. However, it is understood that the present disclosure can be carried out without these specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail to avoid unnecessarily obscuring aspects of the present disclosure.

[0019] The terminology used herein is solely for the purpose of describing specific embodiments and is not intended to limit the present disclosure. As used herein, the singular terms "a" and "an" are intended to include the plural terms as well, unless the context clearly indicates otherwise. Furthermore, it is understood that the terms "comprise," "comprehensive," "include," and "including," when used in this patent description, indicate the presence of the specified features, integers, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, operations, elements, components, and / or sections thereof. As used herein, the term "and / or" includes all combinations of one or more of the related listed items. The expression, for example,"At least one of" when preceding a list of elements can modify the entire list of elements but cannot modify individual elements within the list. When interpreting numerical values, an error or tolerance may occur, even without an explicit description.

[0020] Furthermore, it is self-evident that when a first element or layer is described as being "on" a second element or layer, the first element may be arranged directly on the second element or indirectly on the second element, with a third element or layer positioned between the first and second elements or between the first and second layers. It is also self-evident that when an element or layer is described as being "connected" or "coupled" to another element or layer, it may be located directly on, connected to, or coupled to the other element or layer, or one or more intermediate elements or layers may be present.Furthermore, it is also self-evident that when an element or layer is described as being "between" two elements or layers, it may be the only element or layer between the two elements or layers, or one or more intermediate elements or layers may also be present.

[0021] Furthermore, as used here, if a layer, film, area, plate, or the like is arranged "on" or "on a top side" of another layer, film, area, plate, or the like, the former may directly contact the latter, or yet another layer, film, area, plate, or the like may be arranged between the former and the latter. As used here, if a layer, film, area, plate, or the like is arranged directly "on" or "on a top side" of another layer, film, area, plate, or the like, the former directly contacts the latter, and yet another layer, film, area, plate, or the like is not arranged between the former and the latter.Furthermore, as used here, if a layer, film, area, plate, or the like is arranged "below" or "under" another layer, film, area, plate, or the like, the former may directly contact the latter, or yet another layer, film, area, plate, or the like may be arranged between the former and the latter. As used here, if a layer, film, area, plate, or the like is arranged directly "below" or "under" another layer, film, area, plate, or the like, the former directly contacts the latter, and yet another layer, film, area, plate, or the like is not arranged between the former and the latter.

[0022] In descriptions of temporal relationships, for example, temporally preceding relationships between two events, such as "after", "following", "before", etc., another event may occur in between if "directly after", "directly following" or "directly before" is not specified.

[0023] It is understood that, although the terms "first," "second," "third," and so on may be used here to describe different elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or section from another. Consequently, a first element, component, region, layer, or section described below could be referred to as a second element, component, region, layer, or section without departing from the intent and scope of this disclosure.

[0024] The features of the various embodiments of this disclosure can be partially or completely combined and can be technically related to one another or work together. The exemplary embodiments of this disclosure can be implemented independently of one another and can be implemented in a related manner.

[0025] When interpreting a numerical value, the value is interpreted as encompassing an error range if no separate explicit description of it exists.

[0026] It is self-evident that when an element or layer is described as "connected" or "coupled" to another element or layer, it may be directly attached to, connected to, or coupled to that other element or layer, or one or more intermediate elements or layers may be present. It is also self-evident that when an element or layer is described as "between" two elements or layers, it may be the only element or layer between the two elements or layers, or one or more intermediate elements or layers may also be present.

[0027] The features of the various embodiments of this disclosure can be partially or completely combined and can be technically related to one another or work together. The exemplary embodiments of this disclosure can be implemented independently of one another and can be implemented in a related manner.

[0028] Unless otherwise defined, all terms, including technical and scientific terms used herein, have the same meaning as they would normally be understood by a person skilled in the art in the field to which this inventive concept belongs. Furthermore, it is self-evident that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant field and not in an idealized or overly formal sense, unless expressly defined as such herein.

[0029] As used here, the phrase "adjacent functional groups bond to each other to form a ring structure" means that neighboring functional groups can bond to each other to form a substituted or unsubstituted alicyclic ring structure (cycloalkyl group), a substituted or unsubstituted aromatic ring structure (aryl group), or a ring structure (alkylaryl group or arylalkyl group) with both substituted or unsubstituted aliphatic and aromatic rings. The phrase "adjacent functional group" to a given functional group can mean a functional group that replaces an atom directly bonded to an atom replacing the given functional group, a functional group that is sterically closest to the given functional group, or a functional group that replaces an atom replaced by the given functional group.For example, two functional groups that replace an ortho position in a benzene ring structure and two functional groups that replace the same carbon in an aliphatic ring can be interpreted as “adjacent functional groups”.

[0030] As used here, and unless otherwise stated, the term "substituted" means that the specified group or fraction bears one or more substituents. The term "unsubstituted" means that the specified group bears no substituents.

[0031] As used herein, and unless otherwise specified, the term "substituent" means a non-hydrogen component, for example deuterium, hydroxy, halogen (e.g., fluorine, chlorine, or bromine), carboxamido, imino, alkanoyl, cyano, cyanomethyl, nitro, amino, alkyl, alkenyl, alkynyl, cycloalkyl, arylalkyl, aryl, heterocycle, heteroaryl, hydroxyl, amino, alkoxy, halogen, carboxamido, monoalkylaminosulfmyl, dialkylaminosulfmyl, monoalkylaminosulfonyl, dialkylaminosulfonyl, alkylsulfonylamino, hydroxysulfonyloxy, alkoxysulfonyloxy, alkylsulfonyloxy, hydroxysulfonyl, alkoxysulfonyl, alkylsulfonylalkyl, monoalkylaminosulfonylalkyl, dialkylaminosulfonylalkyl, monoalkylaminosulfmylalkyl, dialkylaminosulfmylalkyl, monoalkylaminosulfmylalkyl, dialkylaminosulfmylalkyl, and the like.

[0032] As used herein, and unless otherwise specified, the term "alkyl" means a substituted or unsubstituted, saturated, linear or branched hydrocarbon chain residue. Examples of alkyl groups include, but are not limited to, linear, branched, or cyclic C1-C15 alkyl, such as... E.g. methyl, ethyl, propyl, isopropyl, cyclopropyl, 2-methyl-1-propyl, 2-methyl-2-propyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-3-butyl, 2,2-dimethyl-1-propyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, and longer alkyl groups, such as B. Heptyl, Octyl, Nonyl and Decyl. An alkyl group can be unsubstituted or substituted with one or two suitable substituents.

[0033] As used herein, and unless otherwise specified, the term "cycloalkyl" means a monocyclic or polycyclic saturated ring with carbon and hydrogen atoms and without carbon-carbon multiple bonds. A cycloalkyl group may be unsubstituted or substituted. Examples of cycloalkyl groups include, but are not limited to, (C3-C7)cycloalkyl groups, including cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl, and saturated cyclic and bicyclic terpenes. A cycloalkyl group may be unsubstituted or substituted. Preferably, the cycloalkyl group is a monocyclic or bicyclic ring.

[0034] As used here, and unless otherwise specified, the term "aryl" means a monocyclic or polycyclic conjugated ring structure well known in the field. Examples of suitable aryl groups or aromatic rings include, but are not limited to, phenyl, tolyl, anthacenyl, fluorenyl, indenyl, azulenyl, and naphthyl. An aryl group may be unsubstituted or substituted with one or two suitable substituents.

[0035] As used herein and unless otherwise specified, the term “substituted aryl” includes an aryl group optionally substituted with one or more functional groups, such as halo, alkyl, haloalkyl (e.g., trifluoromethyl), alkoxy, haloalkoxy (e.g.,difluoromethoxy), alkenyl, alkynyl, aryl, heteroaryl, arylalkyl, aryloxy, aryloxyalkyl, arylalkoxy, alkoxycarbonyl, alkylcarbonyl, arylcarbonyl, arylalkenyl, aminocarbonylaryl, arylthio, arylsulfmyl, arylazo, heteroarylalkyl, heteroarylalkenyl, heteroaryloxy, hydroxy, nitro, Cyano, amino, substituted amino, wherein the amino comprises 1 or 2 substituents (which are optionally substituted alkyl, aryl or any of the other substituents listed herein), thiol, alkylthio, arylthio, heteroarylthio, arylthioalkyl, alkoxyarylthio, alkylaminocarbonyl, arylaminocarbonyl, aminocarbonyl, Alkylcarbonyloxy, Arylcarbonyloxy, Alkylcarbonylamino, Arylcarbonylamino, Arylsulfmyl, Arylsulfmylalkyl, Arylsulfonylamino or arylsulfonaminocarbonyl and / or any of the alkyl substituents listed here.

[0036] As used herein, and unless otherwise specified, the term “heteroaryl,” as used here alone or as part of another group, refers to a 5- to 7-membered aromatic ring comprising 1, 2, 3, or 4 heteroatoms, such as nitrogen, oxygen, or sulfur, and such rings fused to an aryl, cycloalkyl, heteroaryl, or heterocycloalkyl ring (e.g., benzothiophenyl, indolyl), and includes possible N-oxides. “Substituted heteroaryl” comprises a heteroaryl group optionally substituted with 1 to 4 substituents, such as the substituents included above in the definitions of “substituted alkyl” and “substituted cycloalkyl.” Substituted heteroaryl also includes fused heteroaryl groups, such as quinoline, isoquinoline, indole, isoindole, carbazole, acridine, benzimidazole, benzofuran, isobenzofuran, benzothiophene, phenanthroline, purine and the like.

[0037] Below, a structure and a preparation example of an organometallic compound according to the present disclosure and of an organic light-emitting diode with the same are described.

[0038] Traditionally, an organometallic compound has been used as a doping material in the light-emitting layer of an organic light-emitting diode (OLED). For example, 2-phenylpyridine and 2-phenylquinoline, in which a fused ring is introduced into a pyridine moiety within a 2-phenylpyridine structure, are known as the major ligand structure of the organometallic compound. However, the conventional light-emitting doping material has limitations in improving the efficiency and lifetime of the OLED. Consequently, it is necessary to develop a new light-emitting doping material. Therefore, the inventors of the present disclosure have derived a light-emitting doping material that can further improve the efficiency and lifetime of the OLED and have thus carried out the present disclosure.

[0039] In particular, an organometallic compound according to the present invention is one of the compounds 216, 217, 246 and 247.

[0040] The inventors of the present disclosure have experimentally identified that when the organometallic compound according to the invention was used as a doping material of the phosphorescent light emission layer of the organic light-emitting diode, the light emission efficiency and lifetime of the organic light-emitting diode were improved and the operating voltage of the organic light-emitting diode was reduced, and have consequently carried out the present disclosure:

[0041] According to one implementation of the present disclosure, the organometallic compound according to the invention can be used as a doping material that achieves red phosphorescence or green phosphorescence, preferably as a doping material that achieves green phosphorescence.

[0042] With reference to Fig.1. According to one implementation of the present disclosure, an organic light-emitting diode 100 can be provided, comprising a first electrode 110; a second electrode 120 facing the first electrode 110; and an organic layer 130 arranged between the first electrode 110 and the second electrode 120. The organic layer 130 can comprise a light-emitting layer 160, and the light-emitting layer 160 can comprise a host material 160' and doping materials 160". The doping materials 160" can comprise the organometallic compound according to the invention.Furthermore, in the organic light-emitting diode 100, the organic layer 130, which is arranged between the first electrode 110 and the second electrode 120, can be formed by sequentially stacking a hole injection layer 140 (HIL), a hole transport layer 150 (HTL), a light emission layer 160 (EML), an electron transport layer 170 (ETL), and an electron injection layer 180 (EIL) onto the first electrode 110. The second electrode 120 can be formed on the electron injection layer 180, and a protective layer (not shown) can be formed on top of it.

[0043] Although in Fig.Not shown in Figure 1, a hole transport auxiliary layer can also be added between the hole transport layer 150 and the light emission layer 160. The hole transport auxiliary layer can contain a compound with good hole transport properties and can reduce the difference between the HOMO energy levels of the hole transport layer 150 and the light emission layer 160 in order to adjust the hole injection properties. The accumulation of holes at an interface between the hole transport auxiliary layer and the light emission layer 160 can thus be reduced, thereby minimizing a quenching phenomenon in which excitons disappear at the interface due to polarons. Consequently, the degradation of the element can be reduced and the element can be stabilized, thereby improving its efficiency and lifetime.

[0044] The first electrode 110 can act as a positive electrode and can comprise ITO, IZO, tin oxide, or zinc oxide as a conductive material with a relatively high work function value. However, the present disclosure is not limited to this.

[0045] The second electrode 120 can act as a negative electrode and can comprise Al, Mg, Ca, or Ag as a conductive material with a relatively low work function value, or an alloy or combination thereof. However, the present disclosure is not limited to this.

[0046] The hole injection layer 140 can be positioned between the first electrode 110 and the hole transport layer 150. The hole injection layer 140 can have a function for improving interfacial characteristics between the first electrode 110 and the hole transport layer 150 and can be selected from materials with suitable conductivity. The hole injection layer 140 may comprise a compound selected from a group consisting of N1-phenyl-N4,N4-bis(4-(phenyl(tolyl)amino)phenyl)-N1-(tolyl)benzene-1,4-diamine (MTDATA), copper(II) phthalocyanine (CuPc), tris(4-carbazoyl-9-ylphenyl)amine (TCTA), 1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile (HATCN), 1,3,5-tris[4-(diphenylamino)phenyl]benzene (TDAPB), poly(3,4-ethylenedioxythiophene)polystyrenesulfonate (PEDOT / PSS) and N1,N1'-([1,1'-Biphenyl]-4,4'-diyl)bis(N1,N4,N4)-triphenylbenzene-1,4-diamine).Preferably, the hole injection layer can comprise 140 N1,N1'-([1,1'-Biphenyl]-4,4'-diyl)bis(N1,N4,N4-triphenylbenzene-1,4-diamine). However, the present disclosure is limited to this.

[0047] The hole transport layer 150 can be positioned adjacent to the light emission layer 160 and between the first electrode 110 and the light emission layer 160. A material of the hole transport layer 150 can comprise at least one compound selected from the group consisting of N,N'-bis(3-methylphenyl)-N,N'-diphenylbenzidine (TPD), N,N'-di(1-naphthyl)-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (NPB), 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP), N-(biphenyl-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-fluoren-2-amine, N-(biphenyl-4-yl)-N-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)biphenyl)-4-amine, etc. Preferably, the material of the hole transport layer 150 can comprise NPB. However, the present disclosure is not limited thereto.

[0048] According to the present disclosure, the light-emitting layer 160 can be formed by doping a host material 160' with the organometallic compound according to the invention as a doping material 160" in order to improve the luminous efficiency of the diode 100. The doping material 160" can be used as a green or red light-emitting material and preferably as a green phosphorescent material.

[0049] The doping concentration of the doping material 160" according to an exemplary embodiment of the present disclosure can be adjusted to be within a range of 1 to 30 wt% based on a total weight of the host material 160'. However, the disclosure is not limited thereto. The doping concentration can, for example, be in a range of 2 to 20 wt%, 3 to 15 wt%, 5 to 10 wt%, 3 to 8 wt%, 2 to 7 wt%, 5 to 7 wt%, or 5 to 6 wt%.

[0050] The light-emitting layer 160 according to an exemplary embodiment of the present disclosure contains the host material 160', which is known in the field and can achieve an effect of the present disclosure, while the layer 160 contains the organometallic compound of the invention as a doping material 160'. According to the present disclosure, the host material 160' can, for example, comprise a compound containing a carbazole group and can preferably comprise a host material selected from the group consisting of CBP (carbazole biphenyl), mCP (1,3-bis(carbazol-9-yl)), and the like. However, the disclosure is not limited thereto.

[0051] Furthermore, the electron transport layer 170 and the electron injection layer 180 can be stacked sequentially between the light emission layer 160 and the second electrode 120. The electron transport layer 170 requires a material with high electron mobility so that electrons can be stably supplied to the light emission layer with smooth electron transport.

[0052] The material of the electron transport layer 170 may, for example, be known to the field and may comprise at least one compound selected from a group consisting of Alq3 (Tris(8-hydroxyquinolino)aluminium), 8-Hydroxyquinolinolatolithium (Liq), 2-(4-Biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD), 3-(4-Biphenyl)4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), Spiro-PBD, Bis(2-methyl-8-quinolinolate)-4-(phenylphenolato)aluminium (BAlq), Bis(2-methyl-8-hydroxyquinoline)(triphenylsiloxy)aluminium (SAlq), 2,2',2-(1,3,5-benzenetriyl)-tris(1-phenyl-1-H-benzimidazole (TPBi), oxadiazole, triazole, The electron transport layer material consists of phenanthroline, benzoxazole, benzthiazole, and 2-(4-(9,10-di(naphthalen-2-yl)anthracene-2-yl)phenyl)-1-phenyl-1H-benzo[d]imidazole. Preferably, the electron transport layer material 170 can comprise 2-(4-(9,10-di(naphthalen-2-yl)anthracene-2-yl)phenyl)-1-phenyl-1H-benzo[d]imidazole. However, the present disclosure is not limited thereto.

[0053] The electron injection layer 180 serves to facilitate electron injection. A material for the electron injection layer may be known in the field and may comprise at least one compound selected from a group consisting of Alq3 (tris(8-hydroxyquinolino)aluminium), PBD), TAZ), Spiro-PBD, BAlq, SAlq, etc. However, the present disclosure is not limited thereto. Alternatively, the electron injection layer 180 may consist of a metal compound. The metal compound may, for example, comprise one or more selected from a group consisting of Liq, LiF, NaF, KF, RbF, CsF, FrF, BeF2, MgF2, CaF2, SrF2, BaF2, and RaF2. However, the present disclosure is not limited thereto.

[0054] The organic light-emitting diode (OLED) according to an exemplary embodiment of the present disclosure can be embodied as a white LED with a tandem structure. The organic tandem LED according to an explanatory embodiment of the present disclosure can be configured in a structure in which adjacent light-emitting stacks of two or more are interconnected via a charge-generating layer (CGL). The organic LED can comprise at least two light-emitting stacks arranged on a substrate, each of the at least two light-emitting stacks comprising a first and a second electrode facing each other, and the light-emitting layer arranged between the first and second electrodes to emit light in a specific wavelength band. The multiple light-emitting stacks can emit light of the same color or of different colors.Furthermore, one or more light emission layers can be contained in a light emission stack, and the multiple light emission layers can emit light of the same color or different colors.

[0055] In this case, the light emission layer contained in at least one of the multiple light emission stacks can contain the organometallic compound according to the invention as doping materials. Adjacent light emission stacks in the tandem structure can be interconnected via the charge generation layer CGL with an N-type charge generation layer and a P-type charge generation layer.

[0056] Fig. 2 and Fig.Figure 3 are cross-sectional views that schematically show an organic light-emitting diode in a tandem structure with two light emission stacks or an organic light-emitting diode in a tandem structure with three light emission stacks according to some implementations of the present disclosure.

[0057] As in Fig.As shown in Figure 2, an organic light-emitting diode 100 according to an exemplary embodiment of the present disclosure comprises a first electrode 110 and a second electrode 120 facing each other, and an organic layer 230 positioned between the first electrode 110 and the second electrode 120. The organic layer 230 can be positioned between the first electrode 110 and the second electrode 120 and can comprise a first light-emitting stack ST1 with a first light-emitting layer 261, a second light-emitting stack ST2 positioned between the first light-emitting stack ST1 and the second electrode 120 and comprising a second light-emitting layer 262, and the charge-generating layer CGL positioned between the first and second light-emitting stacks ST1 and ST2. The charge generation layer CGL can include an N-type charge generation layer 291 and a P-type charge generation layer 292.The first light-emitting layer 261 and / or the second light-emitting layer 262 can comprise the organometallic compound according to the invention as doping materials. As in . Fig. As shown in Figure 2, for example, the second light emission layer 262 of the second light emission stack ST2 can contain a host material 262' and doping materials 262" doped into it with the organometallic compound according to the invention. Although in Fig.Not shown in Figure 2, each of the first and second light emission stacks ST1 and ST2 can further comprise an additional light emission layer in addition to each of the first light emission layer 261 and the second light emission layer 262. The first light emission layer 261 is positioned between a first hole transport layer 251 and a first electron transport layer 271. Likewise, the second light emission layer 262 is positioned between a second hole transport layer 252 and a second electron transport layer 272. In one embodiment, the first 251 and the second HTL 252 can have a similar or identical structure and similar or identical materials to the HTL 150 of Fig. 1. In one embodiment, the first ETL 271 and the second ETL 272 may have a similar or identical structure and similar or identical materials to the ETL 170 of Fig. exhibit 1.

[0058] As in Fig.As shown in Figure 3, the organic light-emitting diode 100, according to an exemplary embodiment of the present disclosure, comprises the first electrode 110 and the second electrode 120 facing each other, and an organic layer 330 positioned between the first electrode 110 and the second electrode 120. The organic layer 330 can be positioned between the first electrode 110 and the second electrode 120 and can comprise the first light-emitting stack ST1 with the first light-emitting layer 261, the second light-emitting stack ST2 with the second light-emitting layer 262, a third light-emitting stack ST3 with a third light-emitting layer 263, a first charge-generating layer CGL1 positioned between the first and second light-emitting stacks ST1 and ST2, and a second charge-generating layer CGL2 positioned between the second and third light-emitting stacks ST2 and ST3.The first charge-generating layer CGL1 can comprise an N-type charge-generating layer 291 and a P-type charge-generating layer 292. The second charge-generating layer CGL2 can comprise an N-type charge-generating layer 293 and a P-type charge-generating layer 294. The first light-emitting layer 261, the second light-emitting layer 262, and / or the third light-emitting layer 263 can contain the organometallic compound according to the invention as doping materials. As in . Fig. As shown in Figure 3, for example, the second light emission layer 262 of the second light emission stack ST2 can contain the host material 262' and the doping materials 262" doped into it, which consist of the organometallic compound according to the invention. Although in Fig.Not shown in Figure 3, each of the first, second, and third light emission stacks ST1, ST2, and ST3 can further comprise an additional light emission layer in addition to each of the first light emission layer 261, the second light emission layer 262, and the third light emission layer 263. The first light emission layer 261 is positioned between a first hole transport layer 251 and a first electron transport layer 271. Likewise, the second light emission layer 262 is positioned between a second hole transport layer 252 and a second electron transport layer 272. Furthermore, the third light emission layer 263 is positioned between a third hole transport layer 253 and a third electron transport layer 273. In one embodiment, the first HTL 251, the second HTL 252, and the third HTL 253 can have a similar or identical structure and be made of similar or identical materials to the HTL 150 of Fig.1. In one embodiment, the first ETL 271, the second ETL 272, and the third ETL 273 may have a similar or identical structure and similar or identical materials to ETL 170 of Fig. exhibit 1.

[0059] Furthermore, according to an exemplary embodiment of the present disclosure, an organic light-emitting diode can comprise a tandem structure in which four or more light emission stacks and three or more charge generation layers are arranged between the first electrode and the second electrode.

[0060] The organic light-emitting diode according to an exemplary embodiment of the present disclosure can be used as a light-emitting element of any organic light-emitting indicator device and a lighting device. In one implementation, Fig.4 a cross-sectional view which schematically represents an organic light emission indicator device with the organic light-emitting diode according to some embodiments of the present disclosure as the light emission element thereof.

[0061] As in Fig. As shown in Figure 4, an organic light emission indicator device 3000 comprises a substrate 3010, an organic light-emitting diode 4000, and an encapsulation film 3900 covering the organic light-emitting diode 4000. A driver thin-film transistor Td, acting as the driver element, and the organic light-emitting diode 4000, which is connected to the driver thin-film transistor Td, are positioned on the substrate 3010.

[0062] Although in Fig.4 not explicitly shown, a gate line and a data line intersecting to define a pixel area, a power line extending parallel to and spaced apart from one of the gate line and the data line, a switching thin-film transistor connected to the gate line and the data line, and a storage capacitor connected to an electrode of the thin-film transistor and the power line are further formed on the substrate 3010.

[0063] The control thin-film transistor Td is connected to the switching thin-film transistor and comprises a semiconductor layer 3100, a gate electrode 3300, a source electrode 3520 and a drain electrode 3540.

[0064] The semiconductor layer 3100 can be formed on the substrate 3010 and can be made of an oxide semiconductor material or polycrystalline silicon. If the semiconductor layer 3100 is made of an oxide semiconductor material, a light-shielding pattern (not shown) can be formed beneath the semiconductor layer 3100. The light-shielding pattern prevents light from entering the semiconductor layer 3100, thus preventing light-induced degradation of the semiconductor layer 3100. Alternatively, the semiconductor layer 3100 can be made of polycrystalline silicon. In this case, both edges of the semiconductor layer 3100 can be doped with impurities.

[0065] The gate insulating layer 3200, which consists of an insulating material, is formed over a total surface area of ​​the substrate 3010 and on the semiconductor layer 3100. The gate insulating layer 3200 can consist of an inorganic insulating material such as silicon oxide or silicon nitride.

[0066] The gate electrode 3300, which consists of a conductive material such as a metal, is formed on the gate insulating layer 3200 and corresponds to a center of the semiconductor layer 3100. The gate electrode 3300 is connected to the switching thin-film transistor.

[0067] The intermediate insulating layer 3400, which consists of an insulating material, is formed over the entire surface of the substrate 3010 and on the gate electrode 3300. The intermediate insulating layer 3400 can consist of an inorganic insulating material such as silicon oxide or silicon nitride, or an organic insulating material such as benzocyclobutene or photoacrylic.

[0068] The intermediate insulation layer 3400 has a first and a second semiconductor layer contact hole 3420 and 3440 defined therein, each exposing opposite sides of the semiconductor layer 3100. The first and the second semiconductor layer contact holes 3420 and 3440 are each positioned on opposite sides of the gate electrode 3300 and are spaced apart from the gate electrode 3300.

[0069] The source electrode 3520 and the drain electrode 3540, which consist of a conductive material such as metal, are formed on the intermediate insulating layer 3400. The source electrode 3520 and the drain electrode 3540 are positioned around the gate electrode 3300 and are spaced apart from each other, contacting opposite sides of the semiconductor layer 3100 via the first and second semiconductor layer contact holes 3420 and 3440, respectively. The source electrode 3520 is connected to a power line (not shown).

[0070] The semiconductor layer 3100, the gate electrode 3300, the source electrode 3520 and the drain electrode 3540 form the driver thin-film transistor Td. The driver thin-film transistor Td has a coplanar structure in which the gate electrode 3300, the source electrode 3520 and the drain electrode 3540 are positioned on the semiconductor layer 3100.

[0071] Alternatively, the driver thin-film transistor Td can have an inverted staggered structure in which the gate electrode is located below the semiconductor layer, while the source and drain electrodes are located above the semiconductor layer. In this case, the semiconductor layer can be made of amorphous silicon. In one example, the switching thin-film transistor (not shown) can have essentially the same structure as that of the driver thin-film transistor (Td).

[0072] In one example, the organic light emission display device 3000 can include a color filter 3600 that absorbs the light generated by the electroluminescent element (light-emitting diode) 4000. The color filter 3600 can, for example, absorb red (R), green (G), blue (B), and white (W) light. In this case, the light-absorbing patterns of the red, green, and blue color filters can be formed separately in different pixel areas. Each of these color filter patterns can be arranged to overlap with each organic layer 4300 of the organic light-emitting diode 4000 to emit light of a wavelength band corresponding to each color filter. The inclusion of the color filter 3600 can enable the organic light emission display device 3000 to achieve full color.

[0073] For example, if the organic light emission indicator device 3000 is of a bottom emission type, the color filter 3600, which absorbs light, can be positioned on a section of the intermediate insulating layer 3400 corresponding to the organic light-emitting diode 4000. In an optional embodiment, if the organic light emission indicator device 3000 is of a top emission type, the color filter can be positioned on the organic light-emitting diode 4000, that is, on a second electrode 4200. The color filter 3600 can, for example, be configured to have a thickness of 2 to 5 µm.

[0074] In one example, a protective layer 3700 with a drain contact hole 3720, which is defined therein, is designed to expose the drain electrode 3540 of the driving thin-film transistor Td, such that it covers the driving thin-film transistor Td.

[0075] On the protective layer 3700, each first electrode 4100, which is connected to the drain electrode 3540 of the control thin-film transistor Td via the drain contact hole 3720, is individually formed in each pixel area.

[0076] The first electrode 4100 can act as the positive electrode (anode) and can be made of a conductive material with a relatively high work function value. For example, the first electrode 4100 can be made of a transparent conductive material such as ITO, IZO, or ZnO.

[0077] In an example, if the organic light emission indicator device 3000 is of a top-emission type, a reflective electrode or reflective layer may further be formed below the first electrode 4100. The reflective electrode or reflective layer may, for example, comprise aluminum (Al), silver (Ag), nickel (Ni), and / or an aluminum-palladium-copper alloy (APC alloy).

[0078] A bank layer 3800, covering an edge of the first electrode 4100, is formed on the protective layer 3700. The bank layer 3800 exposes a center of the first electrode 4100, corresponding to the pixel area.

[0079] An organic layer 4300 is formed on the first electrode 4100. If required, the organic light-emitting diode 4000 can have a tandem structure. Regarding the tandem structure, see below. Fig. 2 to Fig. 4, which show some embodiments of the present disclosure, and to which reference is made above to the descriptions thereof.

[0080] The second electrode 4200 is formed on the substrate 3010, on which the organic layer 4300 has been formed. The second electrode 4200 is arranged over the entire surface of the display area and consists of a conductive material with a relatively low work function value and can be used as a negative electrode (cathode). The second electrode 4200 can, for example, be made of aluminum (Al), magnesium (Mg), or an aluminum-magnesium alloy (Al-Mg alloy).

[0081] The first electrode 4100, the organic layer 4300 and the second electrode 4200 form the organic light-emitting diode 4000.

[0082] An encapsulation film 3900 is formed on the second electrode 4200 to prevent external moisture from penetrating the organic light-emitting diode 4000. Although in Fig.Not explicitly shown in Figure 4, the encapsulation film 3900 can have a triple-layer structure in which a first inorganic layer, an organic layer, and an inorganic layer are stacked sequentially. However, the present disclosure is not limited to this.

[0083] Below are described a preparatory example and a present example of the present revelation. However, the following present example is only one example of the present revelation. The present revelation is not limited to it. Preparation example - Preparation of a ligand (1) Preparation of ligand A Step 1) Preparation of the ligand connection A-2

[0084] Compounds SM-1 (4.58 g, 20 mmol), SM-2 (3.67 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound A-2 (4.72 g, 82%). Step 2) Preparation of the ligand connection A-1

[0085] Compounds A-2 (5.76 g, 20 mmol), SM-3 (4.28 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound A-1 (6.04 g, 80%). Step 3) Preparation of the ligand connection A

[0086] Compound A-1 (7.55 g, 20 mmol) was dissolved in 80 mL of acetic acid and 25 mL of THF in a 250 mL round-bottom flask under a nitrogen atmosphere. tert-Butyl nitrite (5 mL, 38 mmol) was then added dropwise to the mixture at 0 °C, and the mixture was stirred. After stirring at 0 °C for 4 hours, the temperature was raised to room temperature, and an organic layer was extracted with ethyl acetate and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with dichloromethane and hexane to obtain compound A (4.58 g, 64%). (2) Preparation of the ligand connection B Step 1) Preparation of the ligand connection B-2

[0087] Compounds A-2 (5.76 g, 20 mmol), SM-4 (4.56 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound B-2 (6.50 g, 83%). Step 2) Preparation of the ligand connection B-1

[0088] Compound B-2 (7.83 g, 20 mmol) was dissolved in 80 mL of acetic acid and 25 mL of THF in a 250 mL round-bottom flask under a nitrogen atmosphere. tert-Butyl nitrite (5 mL, 38 mmol) was then added dropwise to the mixture at 0 °C, and the mixture was stirred. After stirring at 0 °C for 4 hours, the temperature was raised to room temperature, and an organic layer was extracted with ethyl acetate and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with dichloromethane and hexane to obtain compound B-1 (5.05 g, 68%). Step 3) Preparation of ligand connection B

[0089] Compound B-1 (7.43 g, 20 mmol) and sodium tert-butoxide (4 mL, 40 mmol) were added to 100 mL of DMSO-d6 in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 135 °C for 48 hours. After completion of the reaction, the reaction vessel was cooled to room temperature, and an organic layer was extracted with ethyl acetate and thoroughly washed with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and dichloromethane to obtain compound B (6.13 g, 82%). (3) Preparation of the ligand connection C Step 1) Preparation of the ligand connection C-2

[0090] Compounds SM-5 (4.86 g, 20 mmol), SM-2 (3.67 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound C-2 (4.77 g, 79%). Step 2) Preparation of the ligand connection C-1

[0091] Compounds C-2 (6.04 g, 20 mmol), SM-3 (4.28 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound C-1 (6.58 g, 84%). Step 3) Preparation of the ligand connection C

[0092] Compound C-1 (7.83 g, 20 mmol) was dissolved in 80 mL of acetic acid and 25 mL of THF in a 250 mL round-bottom flask under a nitrogen atmosphere. tert-Butyl nitrite (5 mL, 38 mmol) was then added dropwise to the mixture at 0 °C, and the mixture was stirred. After stirring at 0 °C for 4 hours, the temperature was raised to room temperature, and an organic layer was extracted with ethyl acetate and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with dichloromethane and hexane to obtain compound C (4.83 g, 65%). (4) Preparation of the ligand connection D Step 1) Preparation of the ligand connection D-2

[0093] Compounds C-2 (6.04 g, 20 mmol), SM-4 (4.56 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound D-2 (6.81 g, 84%). Step 2) Preparation of the ligand connection D-1

[0094] Compound D-2 (8.11 g, 20 mmol) was dissolved in 80 mL of acetic acid and 25 mL of THF in a 250 mL round-bottom flask under a nitrogen atmosphere. tert-Butyl nitrite (5 mL, 38 mmol) was then added dropwise to the mixture at 0 °C, and the mixture was stirred. After stirring at 0 °C for 4 hours, the temperature was raised to room temperature, and an organic layer was extracted with ethyl acetate and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with dichloromethane and hexane to obtain compound D-1 (6.32 g, 82%). Step 3) Preparation of the ligand connection D

[0095] Compound D-1 (7.71 g, 20 mmol) and sodium tert-butoxide (4 mL, 40 mmol) were added to 100 mL of DMSO-d6 in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 135 °C for 48 hours. After completion of the reaction, the reaction vessel was cooled to room temperature, and an organic layer was extracted with ethyl acetate and thoroughly washed with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and dichloromethane to obtain compound D (5.43 g, 70%). (5) Preparation of the ligand connection EStep 1) Preparation of ligand E-2

[0096] Compounds SM-6 (4.58 g, 20 mmol), SM-2 (3.67 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound E-2 (4.90 g, 85%). Step 2) Preparation of the ligand connection E-1

[0097] Compounds E-2 (5.76 g, 20 mmol), SM-3 (4.28 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound E-1 (6.42 g, 85%). Step 3) Preparation of the ligand connection E

[0098] Compound E-1 (7.55 g, 20 mmol) was dissolved in 80 mL of acetic acid and 25 mL of THF in a 250 mL round-bottom flask under a nitrogen atmosphere. tert-Butyl nitrite (5 mL, 38 mmol) was then added dropwise to the mixture at 0 °C, and the mixture was stirred. After stirring at 0 °C for 4 hours, the temperature was raised to room temperature, and an organic layer was extracted with ethyl acetate and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with dichloromethane and hexane to obtain compound E (4.86 g, 68%). (6) Preparation of the ligand connection FStep 1) Preparation of the ligand connection F-2

[0099] Compounds E-2 (5.76 g, 20 mmol), SM-4 (4.56 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound F-2 (6.34 g, 81%). Step 2) Preparation of the ligand connection F-1

[0100] Compound F-2 (7.83 g, 20 mmol) was dissolved in 80 mL of acetic acid and 25 mL of THF in a 250 mL round-bottom flask under a nitrogen atmosphere. tert-Butyl nitrite (5 mL, 38 mmol) was then added dropwise to the mixture at 0 °C, and the mixture was stirred. After stirring at 0 °C for 4 hours, the temperature was raised to room temperature, and an organic layer was extracted with ethyl acetate and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with dichloromethane and hexane to obtain compound F-1 (6.17 g, 83%). Step 3) Preparation of the ligand connection F

[0101] Compound F-1 (7.43 g, 20 mmol) and sodium tert-butoxide (4 mL, 40 mmol) were added to 100 mL of DMSO-d6 in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 135 °C for 48 hours. After completion of the reaction, the reaction vessel was cooled to room temperature, and an organic layer was extracted with ethyl acetate and thoroughly washed with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and dichloromethane to obtain compound F (5.01 g, 67%). (7) Preparation of the ligand connection G Step 1) Preparation of the ligand connection G-2

[0102] Compounds SM-7 (4.86 g, 20 mmol), SM-2 (3.67 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound G-2 (4.83 g, 80%). Step 2) Preparation of the ligand connection G-1

[0103] Compounds G-2 (6.04 g, 20 mmol), SM-3 (4.28 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound G-1 (6.58 g, 84%). Step 3) Preparation of the ligand connection G

[0104] Compound G-1 (7.83 g, 20 mmol) was dissolved in 80 mL of acetic acid and 25 mL of THF in a 250 mL round-bottom flask under a nitrogen atmosphere. tert-Butyl nitrite (5 mL, 38 mmol) was then added dropwise to the mixture at 0 °C, and the mixture was stirred. After stirring at 0 °C for 4 hours, the temperature was raised to room temperature, and an organic layer was extracted with ethyl acetate and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with dichloromethane and hexane to obtain compound G (4.76 g, 64%). (8) Preparation of the ligand connection H Step 1) Preparation of the ligand connection H-2

[0105] Compounds G-2 (6.04 g, 20 mmol), SM-4 (4.56 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound H-2 (6.65 g, 82%). Step 2) Preparation of the ligand connection H-1

[0106] Compound H-2 (8.11 g, 20 mmol) was dissolved in 80 mL of acetic acid and 25 mL of THF in a 250 mL round-bottom flask under a nitrogen atmosphere. tert-Butyl nitrite (5 mL, 38 mmol) was then added dropwise to the mixture at 0 °C, and the mixture was stirred. After stirring at 0 °C for 4 hours, the temperature was raised to room temperature, and an organic layer was extracted with ethyl acetate and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with dichloromethane and hexane to obtain compound H-1 (6.25 g, 81%). Step 3) Preparation of the ligand connection H

[0107] Compound H-1 (7.71 g, 20 mmol) and sodium tert-butoxide (4 mL, 40 mmol) were added to 100 mL of DMSO-d6 in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 135 °C for 48 hours. After completion of the reaction, the reaction vessel was cooled to room temperature, and an organic layer was extracted with ethyl acetate and thoroughly washed with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and dichloromethane to obtain compound H (5.19 g, 67%). (9) Preparation of the ligand connection I Step 1) Preparation of the ligand connection I-3

[0108] Compounds SM-8 (4.58 g, 20 mmol), SM-2 (3.67 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound I-3 (4.67 g, 81%). Step 2) Preparation of the ligand connection I-2

[0109] Compounds I-3 (5.76 g, 20 mmol), SM-4 (4.56 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound I-2 (6.42 g, 82%). Step 3) Preparation of the ligand connection I-1

[0110] Compound I-2 (7.83 g, 20 mmol) was dissolved in 80 mL of acetic acid and 25 mL of THF in a 250 mL round-bottom flask under a nitrogen atmosphere. tert-Butyl nitrite (5 mL, 38 mmol) was then added dropwise to the mixture at 0 °C, and the mixture was stirred. After stirring at 0 °C for 4 hours, the temperature was raised to room temperature, and an organic layer was extracted with ethyl acetate and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with dichloromethane and hexane to obtain compound I-1 (5.80 g, 78%). Step 4) Preparation of the ligand connection I

[0111] Compound I-1 (7.43 g, 20 mmol) and sodium tert-butoxide (4 mL, 40 mmol) were added to 100 mL of DMSO-d6 in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 135 °C for 48 hours. After completion of the reaction, the reaction vessel was cooled to room temperature, and an organic layer was extracted with ethyl acetate and thoroughly washed with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and dichloromethane to obtain compound I (4.86 g, 65%). (10) Preparation of the ligand connection J Step 1) Preparation of the ligand connection J-3

[0112] Compounds SM-9 (4.86 g, 20 mmol), SM-2 (3.67 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound J-3 (4.71 g, 78%). Step 2) Preparation of the ligand connection J-2

[0113] Compounds J-3 (6.04 g, 20 mmol), SM-4 (4.56 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound J-2 (6.49 g, 80%). Step 3) Preparation of the ligand connection J-1

[0114] Compound J-2 (8.11 g, 20 mmol) was dissolved in 80 mL of acetic acid and 25 mL of THF in a 250 mL round-bottom flask under a nitrogen atmosphere. tert-Butyl nitrite (5 mL, 38 mmol) was then added dropwise to the mixture at 0 °C, and the mixture was stirred. After stirring at 0 °C for 4 hours, the temperature was raised to room temperature, and an organic layer was extracted with ethyl acetate and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with dichloromethane and hexane to obtain compound J-1 (5.09 g, 66%). Step 4) Preparation of the ligand connection J

[0115] Compound J-1 (7.71 g, 20 mmol) and sodium tert-butoxide (4 mL, 40 mmol) were added to 100 mL of DMSO-d6 in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 135 °C for 48 hours. After completion of the reaction, the reaction vessel was cooled to room temperature, and an organic layer was extracted with ethyl acetate and thoroughly washed with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and dichloromethane to obtain compound J (6.36 g, 82%). (11) Preparation of the ligand connection K Step 1) Preparation of the ligand connection K-3

[0116] Compounds SM-10 (4.58 g, 20 mmol), SM-2 (3.67 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound K-3 (4.44 g, 77%). Step 2) Preparation of the ligand connection K-2

[0117] Compounds K-3 (5.76 g, 20 mmol), SM-4 (4.56 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound K-2 (6.26 g, 80%). Step 3) Preparation of the ligand connection K-1

[0118] Compound K-2 (7.83 g, 20 mmol) was dissolved in 80 mL of acetic acid and 25 mL of THF in a 250 mL round-bottom flask under a nitrogen atmosphere. tert-Butyl nitrite (5 mL, 38 mmol) was then added dropwise to the mixture at 0 °C, and the mixture was stirred. After stirring at 0 °C for 4 hours, the temperature was raised to room temperature, and an organic layer was extracted with ethyl acetate and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with dichloromethane and hexane to obtain compound K-1 (6.17 g, 83%). Step 4) Preparation of the ligand connection K

[0119] Compound K-1 (7.43 g, 20 mmol) and sodium tert-butoxide (4 mL, 40 mmol) were added to 100 mL of DMSO-d6 in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 135 °C for 48 hours. After completion of the reaction, the reaction vessel was cooled to room temperature, and an organic layer was extracted with ethyl acetate and thoroughly washed with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and dichloromethane to obtain compound K (5.08 g, 68%). (12) Preparation of the ligand connection L Step 1) Preparation of the ligand connection L-3

[0120] Compounds SM-11 (4.86 g, 20 mmol), SM-2 (3.67 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound L-3 (4.53 g, 75%). Step 2) Preparation of the ligand connection L-2

[0121] Compounds L-3 (6.04 g, 20 mmol), SM-4 (4.56 g, 20 mmol), Pd(PPh3)4 (2.31 g, 2 mmol), P(t-Bu)3 (0.81 g, 4 mmol), and NaOtBu (7.68 g, 80 mmol) were dissolved in 200 mL of toluene in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was then heated under reflux and stirred for 12 hours. After completion of the reaction, the temperature was reduced to room temperature, and an organic layer was extracted with dichloromethane and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and hexane to obtain compound L-2 (6.33 g, 78%). Step 3) Preparation of the ligand connection L-1

[0122] Compound L-2 (8.11 g, 20 mmol) was dissolved in 80 mL of acetic acid and 25 mL of THF in a 250 mL round-bottom flask under a nitrogen atmosphere. tert-Butyl nitrite (5 mL, 38 mmol) was then added dropwise to the mixture at 0 °C, and the mixture was stirred. After stirring at 0 °C for 4 hours, the temperature was raised to room temperature, and an organic layer was extracted with ethyl acetate and washed thoroughly with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with dichloromethane and hexane to obtain compound L-1 (5.01 g, 65%). Step 4) Preparation of the ligand connection L

[0123] Compound L-1 (7.71 g, 20 mmol) and sodium tert-butoxide (4 mL, 40 mmol) were added to 100 mL of DMSO-d6 in a 250 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 135 °C for 48 hours. After completion of the reaction, the reaction vessel was cooled to room temperature, and an organic layer was extracted with ethyl acetate and thoroughly washed with water. Moisture was removed with anhydrous magnesium sulfate, and the solution was filtered. It was then concentrated under reduced pressure and separated by column chromatography with ethyl acetate and dichloromethane to obtain compound L (6.51 g, 84%). Preparation example - Preparation of the precursor (iridium precursor) of the iridium compound (1) Preparation of the iridium precursor compound M'Step 1) Preparation of the compound MM

[0124] A mixed solution of compound M (3.38 g, 20 mmol) and IrCl3 (2.39 g, 8.0 mmol) dissolved in ethoxyethanol : distilled water = 90 mL : 30 mL was placed in a 250 mL round-bottom flask under a nitrogen atmosphere and stirred under reflux for 24 hours. After completion of the reaction, the temperature was lowered to room temperature and the resulting solid was separated by reduced-pressure filtration. The solid was filtered using a filter, washed thoroughly with water and cold methanol, and repeatedly subjected to reduced-pressure filtration several times to obtain 4.24 g (94%) of the solid compound MM. Step 2) Preparation of the iridium precursor compound M'

[0125] In a 250 mL round-bottom flask, compound MM (4.51 g, 4 mmol) and silver trifluoromethanesulfonate (AgOTf, 3.02 g, 12 mmol) were dissolved in dichloromethane, and the resulting mixture was stirred at room temperature for 24 hours. Upon completion of the reaction, a solid precipitate was removed by filtration through Celite. The resulting filtrate was filtered and distilled under reduced pressure to obtain 5.34 g (90%) of the resulting solid compound M'. (2) Preparation of the iridium precursor compound B'Step 1) Preparation of the compound BB

[0126] A mixed solution of compound B (7.47 g, 20 mmol) and IrCl3 (2.39 g, 8.0 mmol) dissolved in ethoxyethanol : distilled water = 90 mL : 30 mL was placed in a 250 mL round-bottom flask under a nitrogen atmosphere. The mixture was heated under reflux and stirred for 24 hours. After completion of the reaction, the temperature was lowered to room temperature, and the resulting solid was separated by reduced-pressure filtration. The solid was filtered using a filter, washed thoroughly with water and cold methanol, and repeatedly subjected to reduced-pressure filtration several times to obtain 7.00 g (90%) of the solid compound BB. Step 2) Preparation of the iridium precursor compound B'

[0127] In a 250 mL round-bottom flask, compound BB (7.78 g, 4 mmol) and silver trifluoromethanesulfonate (AgOTf, 3.02 g, 12 mmol) were dissolved in dichloromethane, and the resulting mixture was stirred at room temperature for 24 hours. Upon completion of the reaction, a solid precipitate was removed by filtration through Celite. The resulting filtrate was filtered and distilled under reduced pressure to obtain 3.87 g (84%) of the resulting solid compound B'. (3) Preparation of the iridium precursor compound D'Step 1) Preparation of the compound DD

[0128] A mixed solution of compound D (7.75 g, 20 mmol) and IrCl3 (2.39 g, 8.0 mmol) dissolved in ethoxyethanol : distilled water = 90 mL : 30 mL was placed in a 250 mL round-bottom flask under a nitrogen atmosphere. The mixture was heated under reflux and stirred for 24 hours. After completion of the reaction, the temperature was lowered to room temperature, and the resulting solid was separated by reduced-pressure filtration. The solid was filtered using a filter, washed thoroughly with water and cold methanol, and repeatedly subjected to reduced-pressure filtration several times to obtain 6.88 g (86%) of the solid compound BB. Step 2) Preparation of the iridium precursor compound D'

[0129] In a 250 mL round-bottom flask, compound DD (8.01 g, 4 mmol) and silver trifluoromethanesulfonate (AgOTf, 3.02 g, 12 mmol) were dissolved in dichloromethane, and the resulting mixture was stirred at room temperature for 24 hours. Upon completion of the reaction, a solid precipitate was removed by filtration through Celite. The resulting filtrate was filtered and distilled under reduced pressure to obtain 4.01 g (85%) of the resulting solid compound D'.

[0130] (4) Preparation of the iridium precursor compound F' Step 1) Preparing the FF connection

[0131] A mixed solution of compound F (7.47 g, 20 mmol) and IrCl3 (2.39 g, 8.0 mmol) dissolved in ethoxyethanol : distilled water = 90 mL : 30 mL was added to a 250 mL round-bottom flask under a nitrogen atmosphere. The mixture was heated under reflux and stirred for 24 hours. After completion of the reaction, the temperature was lowered to room temperature, and the resulting solid was separated by reduced-pressure filtration. The solid was filtered using a filter, washed thoroughly with water and cold methanol, and repeatedly subjected to reduced-pressure filtration several times to obtain 6.54 g (84%) of the solid compound FF. Step 2) Preparation of the iridium precursor compound F'

[0132] In a 250 mL round-bottom flask, compound FF (7.78 g, 4 mmol) and silver trifluoromethanesulfonate (AgOTf, 3.02 g, 12 mmol) were dissolved in dichloromethane, and the resulting mixture was stirred at room temperature for 24 hours. Upon completion of the reaction, a solid precipitate was removed by filtration through Celite. The resulting filtrate was filtered and distilled under reduced pressure to obtain 4.05 g (88%) of the resulting solid compound F'. Preparation example - Preparing the iridium connection 1. Preparing the iridium connection 66

[0133] We added the iridium precursor M' (1.11 g, 1.5 mmol) and ligand A (1.07 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 25:75 to obtain iridium compound 66 (1.00 g, 75%). 2. Preparation of the Iridium Compound 67

[0134] We added the iridium precursor M' (1.11 g, 1.5 mmol) and ligand B (1.12 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 25:75 to obtain iridium compound 67 (0.96 g, 71%). 3. Preparation of the Iridium 96 connection

[0135] We added the iridium precursor M' (1.11 g, 1.5 mmol) and the ligand C (1.11 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 25:75 to obtain iridium compound 96 (1.03 g, 76%). 4. Preparation of the Iridium connection 97

[0136] We added the iridium precursor M' (1.11 g, 1.5 mmol) and the ligand D (1.16 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 25:75 to obtain iridium compound 97 (1.11 g, 81%). 5. Preparation of the Iridium compound 216

[0137] We added the iridium precursor M' (1.11 g, 1.5 mmol) and the ligand E (1.07 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 25:75 to obtain iridium compound 216 (1.14 g, 86%). 6. Preparation of the Iridium compound 217

[0138] We added the iridium precursor M' (1.11 g, 1.5 mmol) and the ligand F (1.12 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 25:75 to obtain iridium compound 217 (1.09 g, 81%). 7. Preparation of the Iridium compound 246

[0139] We added the iridium precursor M' (1.11 g, 1.5 mmol) and the ligand G (1.11 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 25:75 to obtain iridium compound 246 (1.07 g, 79%). 8. Preparation of the Iridium compound 247

[0140] We added the iridium precursor M' (1.11 g, 1.5 mmol) and the ligand H (1.16 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 25:75 to obtain iridium compound 247 (1.10 g, 80%). 9. Preparation of the Iridium compound 309

[0141] We added the iridium precursor M' (1.11 g, 1.5 mmol) and the ligand I (1.12 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 25:75 to obtain iridium compound 309 (0.96 g, 71%). 10. Preparation of the Iridium compound 319

[0142] We added the iridium precursor M' (1.11 g, 1.5 mmol) and the ligand J (1.16 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 25:75 to obtain iridium compound 319 (1.04 g, 76%). 11. Preparation of the Iridium connection 349

[0143] We added the iridium precursor M' (1.11 g, 1.5 mmol) and the ligand K (1.12 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at an ethyl acetate:hexane ratio of 25:75 to obtain iridium compound 349 (1.19 g, 88%). 12. Preparation of the Iridium Compound 359

[0144] We added the iridium precursor M' (1.11 g, 1.5 mmol) and the ligand L (1.16 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 25:75 to obtain iridium compound 359 (1.15 g, 84%). 13. Preparation of the Iridium Compound 469

[0145] We added the iridium precursor B' (1.72 g, 1.5 mmol) and the ligand N (0.47 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 50:50 to obtain iridium compound 469 (1.23 g, 75%). 14. Preparation of the Iridium 470 connection

[0146] We added the iridium precursor D' (1.76 g, 1.5 mmol) and the ligand N (0.47 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 50:50 to obtain iridium compound 470 (1.21 g, 72%). 15. Preparation of the Iridium Compound 479

[0147] We added the iridium precursor F' (1.72 g, 1.5 mmol) and the ligand N (0.47 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 50:50 to obtain iridium compound 479 (1.28 g, 78%). 16. Preparation of the Iridium Compound 509

[0148] We added the iridium precursor B' (1.72 g, 1.5 mmol) and the ligand O (0.73 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 40:60 to obtain the iridium compound 509 (1.38 g, 80%). 17. Preparation of the Iridium 510 connection

[0149] We added the iridium precursor D' (1.76 g, 1.5 mmol) and the ligand O (0.73 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 40:60 to obtain the iridium compound 510 (1.39 g, 79%). 18. Preparation of the Iridium connection 519

[0150] We added the iridium precursor F' (1.72 g, 1.5 mmol) and the ligand O (0.73 g, 3 mmol) to 2-ethoxyethanol (50 mL) and DMF (50 mL) in a 150 mL round-bottom flask under a nitrogen atmosphere. The resulting mixture was heated and stirred at 130 °C for 24 hours. Once the reaction was complete, the temperature was reduced to room temperature, and an organic layer was extracted using dichloromethane and distilled water. Moisture was removed by adding anhydrous magnesium sulfate. A filtrate was obtained by filtration and reduced under pressure to yield the crude product. The crude product was purified by column chromatography at a ratio of ethyl acetate to hexane = 40:60 to obtain the iridium compound 519 (1.40 g, 81%). The following examples<Vorliegendes Beispiel 1>

[0151] A glass substrate with a 1000 Å thick ITO (indium tin oxide) film applied to it was washed, followed by ultrasonic cleaning with acetone. The glass substrate was then dried. This resulted in the formation of a transparent ITO electrode. HI-1, as a hole injection material, was deposited onto the transparent ITO electrode in a thermal vacuum deposition chamber. This resulted in the formation of a 60 nm thick hole injection layer. NPB, as a hole transport material, was then deposited onto the hole injection layer in a thermal vacuum deposition chamber. This resulted in a hole transport layer with a thickness of 80 nm. CBP, as a host material for a light emission layer, was then deposited onto the hole transport layer using thermal vacuum deposition. Compound 66, as a dopant, was doped into the host material at a concentration of 5%.Consequently, a light-emitting layer with a thickness of 30 nm was formed. ET-1:Liq (1:1) (30 nm) was deposited on the light-emitting layer as material for an electron transport layer and an electron injection layer. Then, 100 nm thick aluminum was deposited on top to form a negative electrode. In this way, an organic light-emitting diode that emits green light was fabricated. HI-1 means N1,N1'-([1,1'-Biphenyl]-4,4'-diyl)bis(N1,N4,N4-triphenylbenzene-1,4-diamine). ET-1 means 2-(4-(9,10-Di(naphthalen-2-yl)anthracen-2-yl)phenyl)-1-phenyl-1H-benzo[d]imidazole. <Vorliegende Beispiele 2 bis 18 und Vergleichsbeispiele 1 bis 7>

[0152] Organic light-emitting diodes of Examples 2 to 18 and Comparative Examples 1 to 7 were prepared in the same manner as in Example 1, except that the compounds listed in Tables 1 and 2 below were used as the doping material instead of compound 66 in Example 1. Examples 1-4 and 9-18 are not examples according to the invention. <Leistungsbewertung der organischen Leuchtdioden >

[0153] Regarding the organic light-emitting diodes prepared according to the present examples 1 to 18 and comparative examples 1 to 7, operating voltages and efficiency characteristics were determined at 10 mA / cm². 2 Current and lifetime characteristics under acceleration at 20 mA / cm 2The operating voltage (V), EQE (external quantum efficiency) (%), and LT95 (%) were then measured and converted into values ​​relative to reference example 1. The results are shown in Tables 1 and 2 below. LT95 refers to a lifetime rating scheme and represents the time it takes for an organic light-emitting diode to lose 5% of its initial brightness. Table 1 Examples Doping material Operating voltage (V) Maximum luminous efficacy (%, relative value) EQE (%, relative value) LT95 (%, relative value) Comparative example 1 Ref-1 4,25 100 100 100 Comparative example 2 Ref-2 4,26 101 102 101 Comparative example 3 Ref-3 4,25 95 96 105 Comparative example 4 Ref-4 4,32 94 90 101 Comparative example 5 Ref-5 4,30 91 88 104 Comparative example 6 Ref-6 4,31 95 92 100 Comparative example 7 Ref-7 4,34 92 90 106

[0154] The structures of Ref-1 to Ref-7 as doping materials in the comparative examples 1 to 7 in Table 1 above are as follows. Table 2 Examples Doping material Operating voltage (V) Maximum luminous efficacy (%, relative value) EQE (%, relative value) LT95 (%, relative value) The present Connection 66 4,22 110 110 127 Example 1 Example 2 Connection 67 4,21 111 111 129 Example 3 Connection 96 4,22 112 112 130 Example 4 Connection 97 4,21 113 113 132 Example 5 Connection 216 4,23 109 110 124 Example 6 Connection 217 4,24 108 109 125 Example 7 Connection 246 4,22 117 119 127 Example 8 Connection 247 4,23 117 117 129 Example 9 Connection 309 4,24 108 109 124 Present example 10 Connection 319 4,23 112 115 127 Example 11 Connection 349 4,24 106 108 126 Example 12 Connection 359 4,22 112 114 129 Example 13 Connection 469 4,23 116 112 126 Example 14 Connection 470 4,21 115 111 128 Example 15 Connection 479 4,22 116 114 126 Example 16 Connection 509 4,22 117 113 127 Example 17 Connection 510 4,23 118 115 126 Present example 18 Connection 519 4,24 115 114 124

[0155] From the results in Table 1 to Table 2 above, it can be identified that in the organic light-emitting diode in which the organometallic compound of each of the present examples 1 to 18 is used as the doping material of the light emission layer of the diode, compared to those in comparison example 1, the operating voltage of the diode is reduced and the maximum luminous efficiency, the external quantum efficiency (EQE) and the lifetime (LT95) of the diode are improved.

Claims

[1] Organometallic compound selected from a group consisting of compounds 216, 217, 246 and 247: [2] Organic light emission device comprising: a first electrode; a second electrode facing the first electrode; and an organic layer arranged between the first electrode and the second electrode, wherein the organic layer comprises a light-emitting layer, the light emission layer contains a doping material, and the doping material comprises the organometallic compound according to claim 1. [3] Organic light emission device comprising: a first electrode and a second electrode facing each other; and a first light emission stack and a second light emission stack positioned between the first electrode and the second electrode, each of the first light emission stack and the second light emission stack comprising at least one light emission layer, at least one of the light emission layers includes a green phosphorescent light emission layer, the green phosphorescence light emission layer contains a doping material, and the doping material comprises the organometallic compound according to claim 1. [4] Organic light emission device comprising: a first electrode and a second electrode facing each other; and a first light emission stack, a second light emission stack and a third light emission stack positioned between the first electrode and the second electrode, each of the first light emission stack, the second light emission stack and the third light emission stack comprising at least one light emission layer, at least one of the light emission layers includes a green phosphorescent light emission layer, the green phosphorescence light emission layer contains a doping material, and the doping material comprises the organometallic compound according to claim 1. [5] Organic light emission indicator device comprising: a substrate; a control element positioned on the substrate; and an organic light emission element arranged on the substrate and connected to the control element, wherein the organic light emission element comprises the organic light emission device according to any one of claims 2 to 4.

Images