Organic electroluminescent device

Abstract

An organic electroluminescence device of an embodiment includes a first electrode, a second electrode facing the first electrode, and a plurality of organic layers between the first electrode and the second electrode, wherein at least one of the plurality of organic layers includes a fused polycyclic compound represented by the following Formula 1, thereby showing improved emission efficiency. Formula 1.

Description

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2020-0070836, filed on June 11, 2020, the entire contents of which are incorporated herein by reference. Technical Field

[0003] Embodiments of this disclosure relate herein to organic electroluminescent devices and fused polycyclic compounds used therein, for example, to fused polycyclic compounds used as luminescent materials and organic electroluminescent devices comprising such fused polycyclic compounds. Background Technology

[0004] Recently, there has been active development on organic electroluminescent displays (OLEDs) as image displays. Unlike liquid crystal displays (LCDs), OLEDs can be called self-emissive displays, in which holes and electrons injected from a first electrode and a second electrode recombine in an emitting layer, and light is emitted by a luminescent material comprising organic compounds in the emitting layer to achieve display.

[0005] When organic electroluminescent devices are used in displays, it is beneficial to reduce the driving voltage of organic electroluminescent devices and improve emission efficiency and lifetime. Furthermore, research and development of materials for organic electroluminescent devices that can stably meet the requirements are ongoing.

[0006] Recently, in order to realize highly efficient organic electroluminescent devices, phosphorescence emission technology utilizing triplet energy or delayed fluorescence emission technology utilizing the phenomenon of generating singlet excitons through triplet exciton collisions (triplet-triplet annihilation, TTA) is being developed, and thermally activated delayed fluorescence (TADF) materials utilizing the delayed fluorescence phenomenon are also being developed. Summary of the Invention

[0007] Embodiments of this disclosure provide an organic electroluminescent device with improved emission efficiency.

[0008] Embodiments of this disclosure also provide fused polycyclic compounds capable of improving the emission efficiency of organic electroluminescent devices.

[0009] An organic electroluminescent device according to an embodiment of the present disclosure includes a first electrode, a second electrode facing the first electrode, and a plurality of organic layers between the first electrode and the second electrode, wherein at least one of the plurality of organic layers includes a fused polycyclic compound represented by Formula 1 below, and at least one of the plurality of organic layers includes an amine compound represented by Formula a below:

[0010] Formula 1

[0011]

[0012] In Formula 1, Cy1 to Cy7 are each independently a substituted or unsubstituted aromatic hydrocarbon ring or a substituted or unsubstituted aromatic heterocycle, and X1 to X4 are each independently an NR ring. a O or S, R a The alkyl group is substituted or unsubstituted with 1 to 20 carbon atoms, the aryl group is substituted or unsubstituted with 6 to 60 cyclic carbon atoms, or the heteroaryl group is substituted or unsubstituted with 2 to 60 cyclic carbon atoms; Y1 and Y2 are each independently BAr1; Ar1 ​​is substituted or unsubstituted with 6 to 60 cyclic carbon atoms, or the heteroaryl group is substituted or unsubstituted with 2 to 60 cyclic carbon atoms; and m1 and m2 are each independently 0 or 1, wherein at least one selected from m1 and m2 is 1.

[0013] Formula a

[0014]

[0015] In equation a, Ar a To Ar c Each is independently an aryl group with 6 to 60 cyclic carbon atoms, either substituted or unsubstituted, or a heteroaryl group with 2 to 60 cyclic carbon atoms, either substituted or unsubstituted.

[0016] In an embodiment, the plurality of organic layers may include a hole transport region on the first electrode, an emitter layer on the hole transport region, and an electron transport region on the emitter layer, and the emitter layer may include a fused polycyclic compound represented by Formula 1 above.

[0017] In one implementation, the emitting layer may emit delayed fluorescence.

[0018] In an embodiment, the emission layer may be a delayed fluorescence emission layer comprising a host and a dopant, and the dopant may include a fused polycyclic compound represented by Formula 1 above.

[0019] In an embodiment, the emission layer may be a delayed fluorescence emission layer comprising a host and a dopant, and the host may comprise a fused polycyclic compound represented by Formula 1 above.

[0020] In one embodiment, the hole transport region may include a hole injection layer on the first electrode and a hole transport layer on the hole injection layer, and the hole transport layer may include an amine compound represented by the above formula a.

[0021] In an embodiment, the organic electroluminescent device may further include a capping layer on the second electrode having a refractive index of about 1.6 or greater.

[0022] In an embodiment, the fused polycyclic compound represented by Formula 1 above can be represented by Formula 2 below:

[0023] Formula 2

[0024]

[0025] In Formula 2, R1 to R6 are each independently a hydrogen atom, deuterium atom, halogen atom, phosphine oxide group, cyano group, substituted or unsubstituted amino group, substituted or unsubstituted silyl group, substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, substituted or unsubstituted aryl group with 6 to 60 cyclic carbon atoms, or substituted or unsubstituted heteroaryl group with 2 to 60 cyclic carbon atoms, or combined with adjacent groups to form a ring; n1 to n4 are each independently an integer in the range of 0 to 4; n5 is an integer in the range of 0 to 3; n6 is an integer in the range of 0 to 2; and X1 to X4, Y1, Y2, R a Ar1, m1, and m2 are the same as those defined in Equation 1 above.

[0026] In embodiments, the fused polycyclic compound represented by Formula 1 above can be represented by Formulas 3-1 to 3-3 below:

[0027] Equation 3-1

[0028]

[0029] Equation 3-2

[0030]

[0031] Equation 3-3

[0032]

[0033] In formulas 3-1 to 3-3, R7 and R8 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a phosphonium oxide group, a cyano group, a substituted or unsubstituted amino group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, a substituted or unsubstituted aryl group with 6 to 60 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 60 cyclic carbon atoms, or combined with adjacent groups to form a ring, n7 and n8 are each independently an integer in the range of 0 to 5, and X1 to X4, R a R1 to R6 and n1 to n6 are the same as those defined in Equations 1 and 2 above.

[0034] In embodiments, the fused polycyclic compound represented by Formula 1 above can be represented by Formulas 4-1 to 4-6 below:

[0035] Equation 4-1

[0036]

[0037] Equation 4-2

[0038]

[0039] Equation 4-3

[0040]

[0041] Equation 4-4

[0042]

[0043] Equation 4-5

[0044]

[0045] Equation 4-6

[0046]

[0047] In equations 4-1 to 4-6, R 11 To R 14 Each group is independently composed of a hydrogen atom, a deuterium atom, a halogen atom, a phosphonium oxide group, a cyano group, a substituted or unsubstituted amino group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, a substituted or unsubstituted aryl group with 6 to 60 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 60 cyclic carbon atoms, or combined with a neighboring group to form a ring, n 11 up to n 14 Each is an integer in the range of 0 to 5, and Y1, Y2, Ar1, R1 to R6, m1, m2 and n1 to n6 are the same as those defined in Equations 1 and 2 above.

[0048] In an embodiment, the fused polycyclic compound represented by Formula 1 above can be represented by Formula 5 below:

[0049] Formula 5

[0050]

[0051] In Formula 5, Ar2 and Ar3 are each independently an aryl group with 6 to 60 cyclic carbon atoms, either substituted or unsubstituted, or a heteroaryl group with 2 to 60 cyclic carbon atoms, and X1 to X4, R a Y1, Y2, Ar1, m1, and m2 are the same as those defined in Equations 1 and 2 above.

[0052] In the implementation, in Equation 1, when X1 to X4 are each independently NR a At that time, R a It can be a substituted or unsubstituted phenyl group.

[0053] In the embodiments, Ar1 in Formula 1 may be a substituted or unsubstituted phenyl group.

[0054] In the implementation, in Equation 1, when m1 is 1, X1 can be 0 or S, and when m2 is 1, X2 can be 0 or S.

[0055] The fused polycyclic compound according to embodiments of this disclosure can be represented by the above formula 1. Attached Figure Description

[0056] The accompanying drawings are included to provide a further understanding of the subject matter of this disclosure, and are incorporated in and form a part of this specification. The drawings illustrate exemplary embodiments of this disclosure and, together with the description, serve to explain the principles of this disclosure. In the drawings:

[0057] Figure 1 A cross-sectional view of an organic electroluminescent device according to an embodiment of the present disclosure is shown for illustrative purposes.

[0058] Figure 2 A cross-sectional view of an organic electroluminescent device according to an embodiment of the present disclosure is shown for illustrative purposes.

[0059] Figure 3 A cross-sectional view of an organic electroluminescent device according to an embodiment of the present disclosure is shown schematically; and

[0060] Figure 4 A cross-sectional view of an organic electroluminescent device according to an embodiment of the present disclosure is shown for illustrative purposes. Detailed Implementation

[0061] The subject matter of this disclosure may be modified in various ways and may be embodied in different forms, and exemplary embodiments will be explained in more detail with reference to the accompanying drawings. However, the subject matter of this disclosure may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, all modifications, equivalents, and alternatives included within the spirit and scope of this disclosure should be incorporated herein.

[0062] It should be understood that when a component (or area, layer, part, etc.) is referred to as being "on" another component, "connected to" or "coupled to" another component, it may be directly on the other component, directly connected to or directly coupled to the other component, or there may be a third intermediate component.

[0063] The same reference numerals refer to the same components throughout the drawings. Additionally, for clarity, the thickness, scale, and dimensions of the constituent components may be enlarged in the drawings.

[0064] The term “and / or” includes one or more combinations that may be defined by relevant elements.

[0065] It should be understood that although the terms first, second, etc., are used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. Therefore, without departing from the spirit and scope of this disclosure, a first element may be referred to as a second element. Similarly, a second element may be referred to as a first element. Unless the context clearly indicates otherwise, the singular form used herein is intended to include the plural form as well.

[0066] Additionally, the terms "below," "under," "above," and "over" are used to explain the relationship between the elements shown in the accompanying drawings. These terms are relative concepts and are interpreted based on the orientation shown in the drawings, but this disclosure is not limited thereto.

[0067] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It should be further understood that terms defined, for example, in common dictionaries, shall be interpreted as having meanings consistent with their meanings in the context of the relevant field and shall not be interpreted in an ideal or overly formal sense, unless expressly so specified herein.

[0068] It should be further understood that when the terms “comprises” and / or “comprising” are used in this specification, they specify the presence of the described features, numbers, steps, operations, elements, parts or combinations thereof, but do not exclude the presence or addition of one or more other features, numbers, steps, operations, elements, parts or combinations thereof.

[0069] The organic electroluminescent device according to embodiments of the present disclosure will be explained below with reference to the accompanying drawings.

[0070] Figures 1 to 4 A cross-sectional view of an organic electroluminescent device according to an exemplary embodiment of the present disclosure is shown schematically. See also Figures 1 to 4 In the organic electroluminescent device 10 of this embodiment, a first electrode EL1 faces a second electrode EL2, and multiple organic layers may be disposed between the first electrode EL1 and the second electrode EL2. The multiple organic layers may include a hole transport region (HTR), an emitter layer (EML), and an electron transport region (ETR). For example, the organic electroluminescent device 10 of this embodiment may include a first electrode EL1, a hole transport region (HTR), an emitter layer (EML), an electron transport region (ETR), and a second electrode EL2 stacked sequentially. A capping layer (CPL) may be further included on the second electrode EL2.

[0071] The organic electroluminescent device 10 of the embodiments may include, in at least one of a plurality of organic layers between the first electrode EL1 and the second electrode EL2, a fused polycyclic compound, as explained below, in the embodiments described herein. For example, the organic electroluminescent device 10 of the embodiments may include, in the emitter layer EML between the first electrode EL1 and the second electrode EL2, a fused polycyclic compound, as explained below, in the embodiments described herein. However, the embodiments of this disclosure are not limited thereto, and the organic electroluminescent device 10 of the embodiments may include, in at least one organic layer (which are a plurality of organic layers between the first electrode EL1 and the second electrode EL2 other than the emitter layer EML) a fused polycyclic compound, as explained below, in the embodiments described herein, or may include, in the capping layer CPL on the second electrode EL2 a fused polycyclic compound, as explained below, in the embodiments described herein.

[0072] When with Figure 1 When comparing, Figure 2 A cross-sectional view of an organic electroluminescent device 10 according to an embodiment is shown, wherein the hole transport region HTR includes a hole injection layer HIL and a hole transport layer HTL, and the electron transport region ETR includes an electron injection layer EIL and an electron transport layer ETL. Additionally, when... Figure 1 When comparing, Figure 3 A cross-sectional view of an organic electroluminescent device 10 according to an embodiment is shown, wherein the hole transport region HTR includes a hole injection layer HIL, a hole transport layer HTL, and an electron blocking layer EBL, and the electron transport region ETR includes an electron injection layer EIL, an electron transport layer ETL, and a hole blocking layer HBL. When combined with... Figure 2 When comparing, Figure 4 A cross-sectional view of an organic electroluminescent device 10, including a capping layer CPL on the second electrode EL2, is shown.

[0073] In the following explanation of the organic electroluminescent device 10, the emitter layer EML is interpreted as including the fused polycyclic compound according to the embodiments, which will be further explained below; however, the embodiments of this disclosure are not limited thereto. The fused polycyclic compound according to the embodiments, which will be further explained below, may be included in the hole transport region HTR, the electron transport region ETR, and / or the capping layer CPL.

[0074] The first electrode EL1 is conductive (e.g., electrically conductive). The first electrode EL1 can be formed using a metal alloy and / or a conductive compound (e.g., an electrically conductive compound). The first electrode EL1 can be an anode. The first electrode EL1 can be a pixel electrode. The first electrode EL1 can be a transmissive electrode, a transmissive-reflective electrode, or a reflective electrode. If the first electrode EL1 is a transmissive electrode, it can be formed using a transparent metal oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), and / or indium tin zinc oxide (ITZO). If the first electrode EL1 is a transmissive-reflective electrode or a reflective electrode, it can include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, their compounds, or mixtures thereof (e.g., a mixture of Ag and Mg). Simultaneously, the first electrode EL1 can have a structure comprising multiple layers, including a reflective layer or a transmissive-reflective layer formed using the aforementioned materials, and a transmissive conductive layer formed using ITO, IZO, ZnO, and / or ITZO. For example, the first electrode EL1 may include a three-layer structure of ITO / Ag / ITO. However, embodiments of this disclosure are not limited thereto. The thickness of the first electrode EL1 may be approximately to approximately For example, about to approximately Within the range.

[0075] A hole transport region (HTR) is provided on the first electrode EL1. The HTR may include at least one of a hole injection layer (HIL), a hole transport layer (HTL), a hole buffer layer, and an electron blocking layer (EBL). The thickness of the HTR can be approximately [missing information]. to approximately Within the range.

[0076] The hole transport region (HTR) can have a single layer formed using a single material, a single layer formed using multiple different materials, or a multilayer structure including multiple layers formed using multiple different materials.

[0077] For example, the hole transport region HTR may have a single-layer structure of a hole injection layer HIL or a hole transport layer HTL, and may have a single-layer structure formed using a hole injection material and a hole transport material. In some embodiments, the hole transport region HTR may have a single-layer structure formed using a variety of different materials, or a structure of hole injection layer HIL / hole transport layer HTL / hole buffer layer, hole injection layer HIL / hole buffer layer, hole transport layer HTL / hole buffer layer, or hole injection layer HIL / hole transport layer HTL / electron blocking layer EBL stacked from the first electrode EL1, without limitation.

[0078] Hole transport regions (HTRs) can be formed using various suitable methods such as vacuum deposition, spin coating, casting, Langmuir-Brookett (LB) method, inkjet printing, laser printing and / or laser-induced thermal imaging (LITI).

[0079] Hole injection layer HIL may include, for example, phthalocyanine compounds such as copper phthalocyanine, N,N'-diphenyl-N,N'-bis[4-(phenyl-m-tolyl-amino)-phenyl]-phenyl-4,4'-diamine (DNTPD), 4,4',4”-[tris(3-methylphenyl)phenylamino]triphenylamine (m-MTDATA), 4,4',4”-tris(N,N-diphenylamino)triphenylamine (TDATA), 4,4',4”-tri{N-(2-naphthyl)-N-phenylamino}-triphenylamine (2-TNATA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonic acid) (PEDOT / PSS), polyaniline / dodecylbenzenesulfonic acid (PANI / DBSA), polyaniline / camphor sulfonic acid (PANI / CSA), polyaniline / poly(4-styrene sulfonate) (PANI / PSS), N,N'-di(naphthyl-1-yl)-N,N'-diphenyl-benzidine (NPB), triphenylamine-containing polyether ketone (TPAPEK), 4-isopropyl-4'-methyldiphenyliodonium [tetra(pentafluorophenyl)borate] and / or dipyrazino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10,11-hexaonitrile (HAT-CN).

[0080] Hole transport layers (HTLs) include amine compounds represented by the following formula a:

[0081] Formula a

[0082]

[0083] In equation a, Ar a To Ar c Each is independently an aryl group with 6 to 60 cyclic carbon atoms, either substituted or unsubstituted, or a heteroaryl group with 2 to 60 cyclic carbon atoms, either substituted or unsubstituted. a To Ar c It can be, for example, independently substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted biphenyl, substituted or unsubstituted triphenyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted carbazolyl, or substituted or unsubstituted dibenzofuranyl.

[0084] If Ar a To Ar cIf each of the groups is substituted, the substituent may be a substituted or unsubstituted amino group, a substituted or unsubstituted oxygen group, a substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, a substituted or unsubstituted aryl group with 6 to 60 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 60 cyclic carbon atoms. In other respects, if Ar a To Ar c If each of the groups is replaced, the substituent can combine with a neighboring group to form a ring. If Ar a To Ar c Each of them is substituted, and the substituent may be a substituted or unsubstituted amino group, a substituted or unsubstituted oxygen group, a substituted or unsubstituted methyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazolyl group, or a substituted or unsubstituted dibenzofuranyl group.

[0085] In the implementation, Ar a To Ar c Each of them or selected from Ar a To Ar c At least one of the substituents in Ar can be a substituted or unsubstituted fluorenyl group or a substituted or unsubstituted dibenzocyclopentadienyl group. a To Ar c Each of them or selected from Ar a To Ar c At least one of the substituents in each of the substituted groups may be a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted carbazoyl group, or a substituted or unsubstituted dibenzofuranyl group.

[0086] The amine compounds included in the hole transport layer (HTL) can be any one of the compounds represented by compound group a below:

[0087] compound group a

[0088]

[0089] In addition to the amine compounds represented by formula a above, the hole transport layer (HTL) may further include any suitable compounds. The HTL may include, for example, carbazole derivatives such as N-phenylcarbazole and polyvinylcarbazole, fluorine derivatives, N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), triphenylamine derivatives such as 4,4',4”-tris(N-carbazolyl)triphenylamine (TCTA), N,N'-bis(naphthyl-1-yl)-N,N'-diphenyl-benzidine (NPB), 4,4'-cyclohexylbis[N,N-bis(4-methylphenyl)aniline] (TAPC), 4,4'-bis[N,N'-(3-tolyl)amino]-3,3'-dimethylbiphenyl (HMTPD), 1,3-bis(N-carbazolyl)benzene (mCP), etc.

[0090] The thickness of the hole transport region (HTR) can be approximately to approximately For example, about to approximately Within a certain range. The thickness of the hole injection layer (HIL) can be, for example, approximately... to approximately Within a certain range, and the thickness of the hole transport layer (HTL) can be approximately... to approximately Within a certain range. For example, the thickness of the electron blocking layer (EBL) can be approximately... to approximately Within the range described above, if the thicknesses of the hole transport region (HTR), hole injection layer (HIL), hole transport layer (HTL), and electron blocking layer (EBL) satisfy any of the above ranges, then appropriate or satisfactory hole transport properties can be achieved without a significant increase in the driving voltage.

[0091] In addition to the materials described above, the hole transport region (HTR) may further include a charge-generating material to improve conductivity (e.g., electrical conductivity). The charge-generating material may be uniformly or non-uniformly dispersed in the hole transport region (HTR). The charge-generating material may be, for example, a p-doper. The p-doper may be a quinone derivative, a metal oxide, and / or a cyano-containing compound, without limitation. For example, non-limiting examples of p-dopers may include quinone derivatives such as tetracyanoquinone dimethyl (TCNQ) and / or 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanoquinone dimethyl (F4-TCNQ), metal oxides such as tungsten oxide and / or molybdenum oxide, without limitation.

[0092] As described above, in addition to the hole injection layer (HIL) and the hole transport layer (HTL), the hole transport region (HTR) may further include at least one of a hole buffer layer and an electron blocking layer (EBL). The hole buffer layer can compensate for the optical resonant distance according to the wavelength of light emitted from the emitter layer (EML) and can improve the light emission efficiency. Materials that may be included in the hole transport region (HTR) can be used as materials included in the hole buffer layer. The electron blocking layer (EBL) prevents or reduces the injection of electrons from the electron transport region (ETR) into the hole transport region (HTR).

[0093] The emitter layer EML is provided on the hole transport region HTR. The emitter layer EML may have, for example, approximately to approximately or about to approximately The thickness is within the range. The emitter layer (EML) can be a single layer formed using a single material, a single layer formed using multiple different materials, or a multilayer structure with multiple layers formed using multiple different materials.

[0094] In the organic electroluminescent device 10 of the embodiment, the emission layer EML may include the fused polycyclic compound of the embodiment.

[0095] In this specification, the term "substituted or unsubstituted" may mean unsubstituted or substituted with at least one substituent selected from the group consisting of: deuterium, halogen, cyano, nitro, amino, silyl, oxy, thio, sulfinyl, sulfonyl, carbonyl, boron, phosphonyl oxide, phosphonyl sulfide, alkyl, alkenyl, cycloalkyl, aryl, and heterocyclic groups. Additionally, the substituent in each example may be substituted or unsubstituted. For example, biphenyl may be interpreted as aryl or phenyl substituted with phenyl.

[0096] In this specification, the term "forming a ring via bonding with a neighboring group" can mean forming a substituted or unsubstituted hydrocarbon ring or a substituted or unsubstituted heterocycle via bonding with a neighboring group. Hydrocarbon rings include aliphatic hydrocarbon rings and aromatic hydrocarbon rings. Heterocycles include aliphatic heterocycles and aromatic heterocycles. The ring formed by bonding with a neighboring group can be monocyclic or polycyclic. Furthermore, the ring formed by bonding with a neighboring group can bond with another ring to form a spirostructure.

[0097] In this specification, the term "adjacent group" may mean a substituent that replaces an atom directly bonded to the atom substituted by the corresponding substituent, another substituent that replaces the atom substituted by the corresponding substituent, or a substituent spatially positioned closest to the corresponding substituent. For example, in 1,2-dimethylbenzene, the two methyl groups can be interpreted as "adjacent groups" to each other, and in 1,1-diethylcyclopentane, the two ethyl groups can be interpreted as "adjacent groups" to each other.

[0098] In this specification, a halogen atom may be a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

[0099] In this specification, alkyl (e.g., alkyl group) may be straight-chain, branched, or cyclic (e.g., straight-chain alkyl group, branched alkyl group, or cycloalkyl group). The number of carbon atoms in the alkyl (or alkyl group) may be 1 to 50, 1 to 30, 1 to 20, 1 to 10, or 1 to 6. Examples of alkyl groups may include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, cyclopentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, cyclohexyl, 4-methylcyclohexyl, 4-tert-butylcyclohexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-ethyloctyl, 2-butyloctyl, 2-hexyloctyl, 3,7-dimethyloctyl, cyclooctyl, n-nonyl, n-decyl, adamantyl, 2-ethyldecyl, 2-butyldecyl, 2-Hexyldecyl, 2-Octydecyl, undecyl, dodecyl, 2-Ethyldodecyl, 2-Butyldodecyl, 2-Hexyldodecyl, 2-Octydecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, 2-Ethylhexadecyl, 2-Butylhexadecyl, 2-Hexylhexadecyl, 2-Octydecyl, heptadecanyl, octadecyl, nonadecanyl, eicosyl, 2-Ethyleicosyl, 2-Butyleicosyl, 2-Hexyleicosyl, 2-Octydecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecanyl, hexadecyl, octadecyl, nonadecanyl, triadecyl, etc., without limitation.

[0100] In this specification, an alkenyl group may be a hydrocarbon group comprising one or more carbon-carbon double bonds in the main chain (e.g., the middle) or terminal (e.g., the end) of an alkyl group containing two or more carbon atoms. The alkenyl group may be straight-chain or branched. There is no specific limitation on the number of carbon atoms, but it is in the range of 2 to 30, 2 to 20, or 2 to 10. Examples of alkenyl groups include, but are not limited to, vinyl, 1-butenyl, 1-pentenyl, 1,3-butadienyl, styryl, styrylvinyl, etc.

[0101] In this specification, an alkynyl group may be a hydrocarbon group comprising one or more carbon-carbon triple bonds in the main chain (e.g., the middle) or terminal (e.g., the end) of an alkyl group with two or more carbon atoms. The alkynyl group may be straight-chain or branched. There is no specific limitation on the number of carbon atoms, but it is in the range of 2 to 30, 2 to 20, or 2 to 10. Examples of alkynyl groups include ethynyl, propynyl, etc., without limitation.

[0102] In this specification, the hydrocarbon ring may be an optional functional group or substituent derived from an aliphatic hydrocarbon ring, or an optional functional group or substituent derived from an aromatic hydrocarbon ring. The number of carbon atoms in the cyclic hydrocarbon ring may be in the range of 5 to 60, 5 to 30, or 5 to 20.

[0103] In this specification, the aryl group may be an optional functional group or substituent derived from an aromatic hydrocarbon ring. The aryl group may be a monocyclic or polycyclic aryl group. The number of carbons in the aryl group used to form the ring may range from 6 to 60, 6 to 30, 6 to 20, or 6 to 15. Examples of aryl groups may include, but are not limited to, phenyl, naphthyl, fluorenyl, anthraceneyl, phenanthryl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, hexaphenyl, triphenylene, pyrene, benzofluoranthracene, 1,2-benzophenanthryl, etc.

[0104] In this specification, the fluorene group may be substituted, and two substituents may combine with each other to form a spirostructure. Examples of fluorene group substitution are as follows. However, the embodiments of this disclosure are not limited thereto.

[0105]

[0106] In this specification, a heterocyclic group may be an optional functional group or substituent derived from a ring comprising one or more heteroatoms selected from B, O, N, P, Si, and S. Heterocyclic groups include aliphatic heterocyclic groups and aromatic heterocyclic groups. Aromatic heterocyclic groups may be heteroaryl groups. Aliphatic and aromatic heterocycles may be monocyclic or polycyclic.

[0107] In this specification, a heterocyclic group may include one or more of B, O, N, P, Si, and S as heteroatoms. If the heterocyclic group includes two or more heteroatoms, the two or more heteroatoms may be the same or different. The heterocyclic group may be a monocyclic or polycyclic heterocyclic group and has the concept of including a heteroaryl group. The number of carbon atoms in the ring-forming of the heterocyclic group may be in the range of 2 to 30, 2 to 20, or 2 to 10.

[0108] In this specification, aliphatic heterocyclic groups may include one or more selected from B, O, N, P, Si, and S as heteroatoms. The number of carbon atoms in the cyclic group of the aliphatic heterocyclic group may range from 2 to 60, 2 to 30, 2 to 20, or 2 to 10. Examples of aliphatic heterocyclic groups may include, but are not limited to, ethylene oxide, cyclothioalkyl, pyrrolidinyl, piperidinyl, tetrahydrofuranyl, tetrahydrothiophenyl, thioalkyl, tetrahydropyranyl, 1,4-dioxane, etc.

[0109] In this specification, a heteroaryl group may include one or more heteroatoms selected from B, O, N, P, Si, and S. If a heteroaryl group includes two or more heteroatoms, the two or more heteroatoms may be the same or different. The heteroaryl group may be a monocyclic heteroaryl or a polycyclic heteroaryl. The number of carbon atoms in the ring of the heteroaryl group may be in the range of 2 to 60, 2 to 30, 2 to 20, or 2 to 10. Examples of heteroaryl groups may include thienyl, furanyl, pyrrolyl, imidazolyl, triazolyl, pyridyl, bipyridyl, pyrimidinyl, pyrazinyl, triazinyl, acridineyl, pyridazinyl, quinolinyl, quinazolinyl, quinoxazinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, pyrazinopyrazinyl, isoquinolinyl, indolyl, carbazoleyl, N-arylcarbazoleyl, N-heteroarylcarbazoleyl, N-alkylcarbazoleyl, benzoxazolyl, benzoimidazolyl, benzothiazolyl, benzocarbazoleyl, benzothiaphenyl, dibenzothiaphenyl, thiaphenothiaphenyl, benzofuranyl, phenanthrololinyl, thiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, thiadiazolyl, phenothiazinyl, dibenzothiaryl, dibenzofuranyl, etc., without limitation.

[0110] In this specification, the interpretation of aryl groups, except that arylene groups are divalent, can be applied to arylene groups. The interpretation of heteroaryl groups, except that heteroaryl groups are divalent, can be applied to heteroaryl groups.

[0111] In this specification, silane includes alkylsilane and arylsilane. Examples of silane may include trimethylsilane, triethylsilane, tert-butyldimethylsilane, vinyldimethylsilane, propyldimethylsilane, triphenylsilane, diphenylsilane, phenylsilane, etc. However, the embodiments disclosed herein are not limited thereto.

[0112] In this specification, boron groups include alkylboron groups and arylboron groups. Examples of boron groups include, but are not limited to, dimethylboron, diethylboron, tert-butylmethylboron, diphenylboron, phenylboron, etc.

[0113] In this specification, there is no specific limitation on the number of carbon atoms in the amino group, but it can be in the range of 1 to 30. The amino group can include alkylamino, arylamino, or heteroarylamino. Examples of amino groups include methylamino, dimethylamino, phenylamino, naphthylamino, 9-methyl-anthraylamino, etc., without limitation.

[0114] In this specification, the oxygen group may include alkoxy and aryloxy groups. The alkoxy group may be straight-chain, branched, or monocyclic or polycyclic. There is no specific limitation on the number of carbon atoms in the alkoxy group, but it may be in the range of, for example, 1 to 20 or 1 to 10. Examples of oxygen groups may include, but are not limited to, methoxy, ethoxy, n-propoxy, isopropoxy, butoxy, pentoxy, hexoxy, octoxy, nonoxy, decoxy, benzyloxy, etc. The thio group may include alkylthio and arylthio groups.

[0115] In this specification, the alkyl group in alkylthio, alkylsulfonyl, alkylaryl, alkylamine, alkylboryl, and alkylsilyl may be the same as the examples of the alkyl groups described above.

[0116] In this specification, the aryl groups in aryloxy, arylthio, arylsulfonyl, arylamino, arylboryl, and arylsilyl groups may be the same as the examples of aryl groups described above.

[0117] In this specification, direct connections may be single bonds (e.g., single bonds, covalent chemical bonds).

[0118] The fused polycyclic compounds of the embodiments comprise three or four boron atoms and may include a fused structure of seven aromatic rings having three or four boron atoms therebetween. In the fused polycyclic compounds of the embodiments, based on the structure in which three aromatic rings are connected to each of two boron atoms and the two boron atoms are connected to one aromatic ring, that is, a fused structure of two boron atoms and five aromatic rings, the two aromatic rings may be further fused by a nitrogen atom and one or two boron atoms. The fused polycyclic compounds of the embodiments may include a structure in which seven aromatic rings are connected by three or four boron atoms and five heteroatoms, and at least one heteroatom may be a nitrogen atom.

[0119] The fused polycyclic compound of the embodiment can be represented by the following formula 1.

[0120] Formula 1

[0121]

[0122] In Formula 1, Cy1 to Cy7 are each independently a substituted or unsubstituted aromatic hydrocarbon ring or a substituted or unsubstituted aromatic heterocycle. Cy1 to Cy7 may each be independently a substituted or unsubstituted five- or six-membered aromatic hydrocarbon ring or a substituted or unsubstituted five- or six-membered aromatic heterocycle. In an embodiment, Cy1 to Cy7 may each be independently a substituted or unsubstituted benzene ring.

[0123] In Equation 1, X1 to X4 can each be independently represented as NR. a X1 to X4 can be the same as or different from each other. In the implementation, X1 to X4 can all be O, S, or NR. aIn some implementations, one of X1 to X4 may be NR. a And the remaining three can be O or S. In some embodiments, two of X1 to X4 can be NR. a And the remaining two can be O or S. In some embodiments, three selected from X1 to X4 can be NR. a And the remaining one can be O or S.

[0124] In Equation 1, R a It can be an alkyl group with 1 to 20 carbon atoms, substituted or unsubstituted, an aryl group with 6 to 60 cyclic carbon atoms, or a heteroaryl group with 2 to 60 cyclic carbon atoms, substituted or unsubstituted. R a It can be an aryl group with 6 to 30 cyclic carbon atoms, either substituted or unsubstituted, or a heteroaryl group with 2 to 30 cyclic carbon atoms, either substituted or unsubstituted. In embodiments, R a It can be a substituted or unsubstituted phenyl group. In the embodiments, R a It can be an unsubstituted phenyl or a phenyl substituted with a methyl group.

[0125] In Formula 1, Y1 and Y2 can each independently be BAr1. Ar1 can be a substituted or unsubstituted aryl group with 6 to 60 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 60 cyclic carbon atoms. In embodiments, Ar1 can be a substituted or unsubstituted phenyl group. In embodiments, Ar1 can be an unsubstituted phenyl group or a phenyl group substituted with a methyl group.

[0126] In Equation 1, m1 and m2 are each independently 0 or 1. A case where m1 is 0 implies that Cy1 and Cy3 are not connected via Y1, and a case where m1 is 1 implies that Cy1 and Cy3 are connected via Y1. A case where m2 is 0 implies that Cy2 and Cy3 are not connected via Y2, and a case where m2 is 1 implies that Cy2 and Cy3 are connected via Y2. At least one of m1 and m2 can be 1. In embodiments, m1 can be 1 and m2 can be 0, or m2 can be 1 and m1 can be 0, or both m1 and m2 can be 1. For example, excluding the case where m1 and m2 are both 0 in Equation 1, boron groups connecting Cy1 and Cy3 and / or Cy2 and Cy3 can exist.

[0127] Compared to existing polycyclic compounds whose nuclei include nitrogen and boron atoms, the fused polycyclic compounds of the embodiments comprise three or four boron atoms and have a structure in which seven aromatic rings are connected by three or four boron atoms and five heteroatoms, thereby possessing a multiple resonance structure with a broad plate-like framework (e.g., the core of the fused polycyclic compound has a broad plate-like structure located in the same or substantially the same plane). Therefore, the fused polycyclic compounds of the embodiments comprise three or four boron atoms and exhibit a broad plate-like framework and multiple resonances, thus allowing for easy separation of the HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) states in a molecule, and enabling the fused polycyclic compounds to be used as materials for emitting delayed fluorescence. Due to this structure, the fused polycyclic compounds of the embodiments can have a reduced difference (ΔE) between the lowest triplet excitation level (T1 level) and the lowest singlet excitation level (S1 level). ST Therefore, if used as a material for emitting delayed fluorescence, the emission efficiency of organic electroluminescent devices can be further improved.

[0128] The fused polycyclic compound represented by Formula 1 can be represented by Formula 2 below.

[0129] Formula 2

[0130]

[0131] Equation 2 represents Equation 1, where Cy1 to Cy7 are designated as substituted or unsubstituted benzene rings.

[0132] In Formula 2, R1 to R6 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a phosphonium oxide group, a cyano group, a substituted or unsubstituted amino group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, a substituted or unsubstituted aryl group with 6 to 60 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 60 cyclic carbon atoms, or may be combined with adjacent groups to form a ring. R1 to R6 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted aromatic amino group, a substituted or unsubstituted alkyl group with 1 to 10 carbon atoms, a substituted or unsubstituted aryl group with 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 30 cyclic carbon atoms. In embodiments, R1 to R6 may each independently be a hydrogen atom, a substituted or unsubstituted diphenylamino group, or a substituted or unsubstituted carbazole group.

[0133] In Formula 2, n1 to n4 are each independently an integer in the range of 0 to 4. When n1 is 0, the fused polycyclic compound according to the embodiment may not be substituted by R1. When n1 is 4 and all R1 groups are hydrogen atoms, the situation is the same as when n1 is 0. When n1 is 2 or a larger integer, the plurality of R1 groups may be the same, or at least one of the plurality of R1 groups may be different. When n2 is 0, the fused polycyclic compound according to the embodiment may not be substituted by R2. When n2 is 4 and all R2 groups are hydrogen atoms, the situation is the same as when n2 is 0. When n2 is 2 or a larger integer, the plurality of R2 groups may be the same, or at least one of the plurality of R2 groups may be different. When n3 is 0, the fused polycyclic compound according to the embodiment may not be substituted by R3. When n3 is 4 and all R3 groups are hydrogen atoms, the situation is the same as when n3 is 0. When n3 is 2 or a larger integer, the plurality of R3 groups may be the same, or at least one of the plurality of R3 groups may be different. When n4 is 0, the fused polycyclic compound according to the embodiment may not be substituted by R4. The case where n4 is 4 and all R4 groups are hydrogen atoms is the same as the case where n4 is 0. When n4 is 2 or a larger integer, the plurality of R4 groups may be the same, or at least one of the plurality of R4 groups may be different.

[0134] In Formula 2, n5 is an integer in the range of 0 to 3. When n5 is 0, the fused polycyclic compound according to the embodiment may not be substituted with R5. The case where n5 is 3 and all R5 groups are hydrogen atoms is the same as the case where n5 is 0. When n5 is 2 or a larger integer, the plurality of R5 groups may be the same, or at least one of the plurality of R5 groups may be different.

[0135] In Formula 2, n6 is an integer in the range of 0 to 2. When n6 is 0, the fused polycyclic compound according to the embodiment may not be substituted with R6. The case where n6 is 2 and all R6 groups are hydrogen atoms is the same as the case where n6 is 0. When n6 is 2, the plurality of R6 groups may be the same, or at least one of the plurality of R6 groups may be different.

[0136] In Equation 2, X1 to X4, Y1, Y2, and R can be applied as referenced in Equation 1 above. a Ar1, m1, and m2 have the same interpretation.

[0137] Fused polycyclic compounds represented by Formula 1 can be represented by Formulas 3-a to 3-c below.

[0138] Equation 3-a

[0139]

[0140] Equation 3-b

[0141]

[0142] Formula 3-c

[0143]

[0144] Equations 3-a to 3-c correspond to Equation 2, where m1 and m2 are specified as 0 or 1.

[0145] In equations 3-a to 3-c, X1 to X4 and R, which are referenced from equations 1 and 2 above, can be applied. a The same interpretation for Y1, Y2, R1 to R6 and n1 to n6.

[0146] Fused polycyclic compounds represented by Formula 1 can be represented by Formulas 3-1 to 3-3 below.

[0147] Equation 3-1

[0148]

[0149] Equation 3-2

[0150]

[0151] Equation 3-3

[0152]

[0153] Formulas 3-1 to 3-3 correspond to Formula 2, where Ar1 is specified as a substituted or unsubstituted phenyl group, and m1 and m2 are specified as 0 or 1.

[0154] In Formulas 3-1 to 3-3, R7 and R8 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a phosphono group, a cyano group, a substituted or unsubstituted amino group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, a substituted or unsubstituted aryl group with 6 to 60 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 60 cyclic carbon atoms, or combined with adjacent groups to form a ring. R7 and R8 may each independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted aromatic amino group, a substituted or unsubstituted alkyl group with 1 to 10 carbon atoms, a substituted or unsubstituted aryl group with 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 30 cyclic carbon atoms. In embodiments, R7 and R8 may each independently be a hydrogen atom, a substituted or unsubstituted diphenylamino group, or a substituted or unsubstituted carbazole group.

[0155] In Formulas 3-1 to 3-3, n7 and n8 are each independently an integer ranging from 0 to 5. When n7 is 0, the fused polycyclic compound according to the embodiment may not be substituted by R7. The case where n7 is 5 and all R7 groups are hydrogen atoms is the same as the case where n7 is 0. When n7 is 2 or a larger integer, the plurality of R7 groups may be the same, or at least one of the plurality of R7 groups may be different. When n8 is 0, the fused polycyclic compound according to the embodiment may not be substituted by R8. The case where n8 is 5 and all R8 groups are hydrogen atoms is the same as the case where n8 is 0. When n8 is 2 or a larger integer, the plurality of R8 groups may be the same, or at least one of the plurality of R8 groups may be different.

[0156] In equations 3-1 to 3-3, X1 to X4 and R, which are referenced from equations 1 and 2 above, can be applied. a The same interpretation for R1 to R6 and n1 to n6.

[0157] Fused polycyclic compounds represented by Formula 1 can be represented by Formulas 4-1 to 4-6 below.

[0158] Equation 4-1

[0159]

[0160] Equation 4-2

[0161]

[0162] Equation 4-3

[0163]

[0164] Equation 4-4

[0165]

[0166] Equation 4-5

[0167]

[0168] Equation 4-6

[0169]

[0170] Equations 4-1 to 4-6 correspond to Equation 2, where X1 to X4 are specified as NR. a Or O.

[0171] In equations 4-1 to 4-6, R 11 To R 14Each group is independently a hydrogen atom, a deuterium atom, a halogen atom, a phosphonium oxide group, a cyano group, a substituted or unsubstituted amino group, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group with 1 to 20 carbon atoms, a substituted or unsubstituted aryl group with 6 to 60 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 60 cyclic carbon atoms, or may be combined with a neighboring group to form a ring. R 11 To R 14 Each of these can independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted aromatic amino group, a substituted or unsubstituted alkyl group with 1 to 10 carbon atoms, a substituted or unsubstituted aryl group with 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 30 cyclic carbon atoms. In embodiments, R 11 To R 14 Each can be independently a hydrogen atom, a substituted or unsubstituted diphenylamine group, or a substituted or unsubstituted carbazole group.

[0172] In equations 4-1 to 4-6, n 11 up to n 14 Each is an independent integer in the range of 0 to 5. Where n 11 When the value is 0, the fused polycyclic compound according to the embodiment may not be affected by R. 11 Replacement. Where n 11 It is 5 and all R 11 When all groups are hydrogen atoms, it can be combined with n. 11 The case where n is 0 is the same. 11 In the case of integers 2 or greater, multiple R 11 The groups can be the same, or multiple R groups. 11 At least one of the groups can be different. Where n 12 When the value is 0, the fused polycyclic compound according to the embodiment may not be affected by R. 12 Replacement. Where n 12 It is 5 and all R 12 When all groups are hydrogen atoms, it can be combined with n. 12 The case where n is 0 is the same. 12 In the case of integers 2 or greater, multiple R 12 The groups can be the same, or multiple R groups. 12 At least one of the groups can be different. Where n 13 When the value is 0, the fused polycyclic compound according to the embodiment may not be affected by R. 13 Replacement. Where n 13 For 5 and all R 13 When all groups are hydrogen atoms, it can be combined with n. 13 The case where n is 0 is the same. 13 In the case of integers 2 or greater, multiple R13 The groups can be the same, or multiple R groups. 13 At least one of the groups can be different. Where n 14 When the value is 0, the fused polycyclic compound according to the embodiment may not be affected by R. 14 Replacement. Where n 14 For 5 and all R 14 When all groups are hydrogen atoms, it can be combined with n. 14 The case where n is 0 is the same. 14 In the case of integers 2 or greater, multiple R 14 The groups can be the same, or multiple R groups. 14 At least one of the groups may be different.

[0173] In Equations 4-1 to 4-6, the same interpretations of Y1, Y2, Ar1, R1 to R6, m1, m2, and n1 to n6 as referred to in Equations 1 and 2 above can be applied.

[0174] The fused polycyclic compound represented by Formula 1 can be represented by Formula 5 below.

[0175] Formula 5

[0176]

[0177] Equation 5 corresponds to Equation 2, where n1 to n4 and n6 are 0, n5 is 1, the substitution position of R5 is specified, and R5 is specified as the substituted amino group.

[0178] In Formula 5, Ar2 and Ar3 can each be independently a substituted or unsubstituted aryl group with 6 to 60 cyclic carbon atoms or a substituted or unsubstituted heteroaryl group with 2 to 60 cyclic carbon atoms. In embodiments, Ar2 and Ar3 can be substituted or unsubstituted phenyl groups.

[0179] In Equation 5, X1 to X4 and R, which are referenced from Equations 1 and 2 above, can be applied. a The same interpretation for Y1, Y2, Ar1, m1, and m2.

[0180] The fused polycyclic compound in the embodiments may be any one of the compounds represented in compound group 1 below. The organic electroluminescent device 10 of the embodiments may include at least one fused polycyclic compound selected from the compounds represented in compound group 1 in the emitting layer EML.

[0181] Compound group 1

[0182]

[0183]

[0184] The fused polycyclic compound of the embodiment represented by Formula 1 can be a material for emitting thermally activated delayed fluorescence. Additionally, the fused polycyclic compound of the embodiment represented by Formula 1 can be a thermally activated delayed fluorescence dopant having a difference (ΔE) between the lowest triplet excitation energy level (T1 level) and the lowest singlet excitation energy level (S1 level) of about 0.35 eV or less. ST ).

[0185] The fused polycyclic compound of the embodiment represented by Formula 1 can be a luminescent material having a central emission wavelength in the wavelength region ranging from about 430 nm to about 490 nm. For example, the fused polycyclic compound of the embodiment represented by Formula 1 can be a blue thermally activated delayed fluorescence (TADF) dopant. However, the embodiments of this disclosure are not limited thereto, and when using the fused polycyclic compound of the embodiment as a luminescent material, the fused polycyclic compound can be used as a dopant material emitting light in various suitable wavelength regions, such as red emitting dopant and green emitting dopant. In some embodiments, the fused polycyclic compound of the embodiment represented by Formula 1 can be the main component.

[0186] In the organic electroluminescent device 10 of the embodiment, the emitting layer EML can emit delayed fluorescence. For example, the emitting layer EML can emit thermally activated delayed fluorescence (TADF).

[0187] In the organic electroluminescent device 10 of the embodiment, the emission layer EML may include two or more fused polycyclic compounds represented by Formula 1. In the embodiment, the emission layer EML may include a first fused polycyclic compound represented by Formula 1 and a second fused polycyclic compound represented by Formula 1 but different from the first fused polycyclic compound. In the emission layer EML, the first fused polycyclic compound may be the host, and the second fused polycyclic compound may be a dopant.

[0188] Additionally, the emitting layer EML of the organic electroluminescent device 10 can emit blue light. For example, the emitting layer EML of the organic electroluminescent device 10 in the embodiment can emit blue light in a region of about 490 nm or smaller. However, the embodiments of this disclosure are not limited to this, and the emitting layer EML can also emit green or red light.

[0189] In some embodiments, the organic electroluminescent device 10 of the embodiment may include a plurality of emission layers EML. The plurality of emission layers EML may be stacked one on top of the other. For example, the organic electroluminescent device 10 including a plurality of emission layers EML may emit white light. The organic electroluminescent device 10 including a plurality of emission layers EML may be an organic electroluminescent device having a series structure. If the organic electroluminescent device 10 includes a plurality of emission layers EML, at least one emission layer EML may include a fused polycyclic compound of the embodiment.

[0190] In embodiments, the emission layer EML includes a host and a dopant, and may include fused polycyclic compounds of the embodiments as the host and / or dopant. For example, in the organic electroluminescent device 10 of the embodiments, the emission layer EML may include a host for emitting delayed fluorescence and a dopant for emitting delayed fluorescence, and may include a fused polycyclic compound as the dopant for emitting delayed fluorescence. The emission layer EML may include at least one selected from the fused polycyclic compounds represented in compound group 1 as a thermally activated delayed fluorescence dopant. In some embodiments, the emission layer EML may include at least one selected from the fused polycyclic compounds represented in compound group 1 as a host, and another selected from the fused polycyclic compounds represented in compound group 1 as a thermally activated delayed fluorescence dopant. In embodiments, the emission layer EML may be a delayed fluorescence emission layer.

[0191] In embodiments, in addition to the polycyclic compound represented by Formula 1, the emitter layer EML may also include any suitable host material. Any suitable material can be used as the host material of the emitter layer EML, and it can be a fluoranthene derivative, a pyrene derivative, an aromatic yne derivative, anthracene derivative, a fluorene derivative, a perylene derivative, and / or a 1,2-benzophenanthrene derivative, without specific limitation. In some embodiments, a pyrene derivative, a perylene derivative, and / or anthracene derivative may be used. For example, an anthracene derivative represented by Formula 6 below may be used as the host material of the emitter layer EML.

[0192] Formula 6

[0193]

[0194] In Equation 6, R 31 To R 40 Each of these groups can independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group with 1 to 10 carbon atoms, a substituted or unsubstituted aryl group with 6 to 30 cyclic carbon atoms, or a substituted or unsubstituted heteroaryl group with 2 to 30 cyclic carbon atoms, or can be combined with adjacent groups to form a ring. Additionally, R 31 To R 40 It can combine with neighboring groups to form saturated or unsaturated hydrocarbon rings.

[0195] In Equation 6, "c" and "d" can each be an integer in the range of 0 to 5.

[0196] The compound represented by Formula 6 can be any one of the compounds 6-1 to 6-16 below.

[0197]

[0198]

[0199] In embodiments, the emitter layer (EML) may include, as a host material, tris(8-hydroxyquinoline)aluminum (Alq3), 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP), poly(N-vinylcarbazole) (PVK), 9,10-bis(naphthyl-2-yl)anthracene (ADN), 4,4',4”-tris(carbazolyl-9-yl)triphenylamine (TCTA), 1,3,5-tris(N-phenylbenzimidazolyl-2-yl)benzene (TPBi), 3-tert-butyl-9,10-bis(naphthyl-2-yl)anthracene (TBADN), stilbene aromatic hydrocarbon (DSA), 4,4'-bis(9-carbazolyl)-2,2'-dimethylbiphenyl (CDBP), 2-methyl -9,10-bis(naphthyl-2-yl)anthracene (MADN), bis[2-(diphenylphosphine)phenyl]ether oxide (DPEPO), hexaphenylcyclotriphosphazene (CP1), 1,4-bis(triphenylsilyl)benzene (UGH2), hexaphenylcyclotrisiloxane (DPSiO3), octaphenylcyclotetrasiloxane (DPSiO4), 2,8-bis(diphenylphospho)dibenzofuran (PPF), 3,3'-bis(N-carbazolyl)-1,1'-biphenyl (mCBP), 1,3-bis(N-carbazolyl)benzene (mCP), etc. However, embodiments of this disclosure are not limited thereto. Any suitable host material for emitting delayed fluorescence may be included in addition to the suggested host materials.

[0200] In the organic electroluminescent device 10 of the embodiment, the emission layer EML may further include any suitable dopant material. In the embodiment, the emission layer EML may include styrene derivatives as dopant (e.g., 1,4-bis[2-(3-N-ethylcarbazolyl)vinyl]benzene (BCzVB), 4-(di-p-tolylamino)-4'-[(di-p-tolylamino)styrene]stilbene (DPAVB) and / or N-(4-((E)-2-(6-((E)-4-(diphenylamino)styrene)naphth-2-yl)vinyl)phenyl)-N-phenylaniline (N-BDAVBi)), perylene and / or its derivatives (e.g., 2,5,8,11-tetra-tert-butylperylene (TBP)), pyrene and / or its derivatives (e.g., 1,1'-dipyrene, 1,4-dipyrenebenzene, 1,4-bis(N,N-diphenylamino)pyrene), etc.

[0201] Furthermore, in embodiments, the emitter layer EML may include two different dopant materials having different lowest triplet excitation energy levels (T1 levels). In the organic electroluminescent device 10 of the embodiment, the emitter layer EML may include a body having a first lowest triplet excitation energy level, a first dopant having a second lowest triplet excitation energy level lower than the first lowest triplet excitation energy level, and a second dopant having a third lowest triplet excitation energy level lower than the second lowest triplet excitation energy level. In embodiments, the emitter layer EML may include the fused polycyclic compound of the above-described embodiments as the first dopant.

[0202] In the organic electroluminescent device 10, which includes a host, a first dopant, and a second dopant in the emitter layer (EML), the first dopant may be a delayed fluorescence dopant, and the second dopant may be a fluorescent dopant. Furthermore, in the organic electroluminescent device 10 of this embodiment, the fused polycyclic compound represented by Formula 1 may serve as an auxiliary dopant.

[0203] For example, in the case where the emission layer EML of the organic electroluminescent device 10 in one embodiment includes multiple dopants, the emission layer EML may include the fused polycyclic compound of the embodiment as a first dopant and the above-mentioned suitable dopant material as a second dopant. For example, in the case where the emitting layer EML emits blue light, the emitting layer EML may further include, as a second dopant, any one selected from the group consisting of: styrene derivatives (e.g., 1,4-bis[2-(3-N-ethylcarbazolyl)vinyl]benzene (BCzVB), 4-(di-p-tolylamino)-4'-[(di-p-tolylamino)styrene]stilbene (DPAVB) and / or N-(4-((E)-2-(6-((E)-4-(diphenylamino)styrene)naphth-2-yl)vinyl)phenyl)-N-phenylaniline (N-BDAVBi)), perylene and / or its derivatives (e.g., 2,5,8,11-tetra-tert-butylperylene (TBP)), pyrene and / or its derivatives (e.g., 1,1'-dipyrene, 1,4-dipyrenebenzene and 1,4-bis(N,N-diphenylamino)pyrene), etc. In addition, metal complexes or organometallic complexes, including Ir, Pt, Pd, etc., which are nuclear atoms, such as (4,6-F2ppy)2Irpic, can be used as second dopants.

[0204] In the organic electroluminescent device 10, which includes the embodiment of using a fused polycyclic compound as the first dopant of the emission layer EML, the emission layer EML can emit green or red light, and in this case, the second dopant material used can be the aforementioned suitable dopant, any suitable green fluorescent dopant, or any suitable red fluorescent dopant.

[0205] In the organic electroluminescent device 10 of the embodiment, the emission layer EML may be a phosphorescent emission layer. For example, a fused polycyclic compound according to the embodiment may be included in the emission layer EML as a phosphorescent host material or a dopant material.

[0206] In the organic electroluminescent device 10 of the embodiment, such as Figures 1 to 4 As shown, the electron transport region (ETR) is provided on the emitter layer (EML). The electron transport region (ETR) may include at least one selected from the hole blocking layer (HBL), the electron transport layer (ETL), and the electron injection layer (EIL). However, embodiments of this disclosure are not limited thereto.

[0207] The electronic transmission region (ETR) can have a single layer made of a single material, a single layer made of multiple different materials, or a multi-layer structure with multiple layers made of multiple different materials.

[0208] For example, the electron transport region (ETR) can have a single-layer structure of either the electron injection layer (EIL) or the electron transport layer (ETL), or a single-layer structure formed using an electron injection material and an electron transport material. Furthermore, the ETR can have a single-layer structure containing multiple different materials, or a stacked structure of electron transport layer (ETL) / electron injection layer (EIL) or hole blocking layer (HBL) / electron transport layer (ETL) / electron injection layer (EIL), without limitation. The thickness of the ETR can be, for example, approximately [missing information - likely a number]. to approximately Within the range.

[0209] Electron transfer regions (ETRs) can be formed using various suitable methods such as vacuum deposition, spin coating, casting, Langmuir-Brookett (LB) method, inkjet printing, laser printing and / or laser-induced thermal imaging (LITI).

[0210] If the electron transport region (ETR) includes an electron transport layer (ETL), the ETL may include anthracene compounds. The ETL may include, for example, tris(8-hydroxyquinoline)aluminum (Alq3), 1,3,5-tris[(3-pyridyl)-benzene-3-yl]benzene, 2,4,6-tris(3'-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine, 2-(4-(N-phenylbenzimidazol-1-yl)phenyl)-9,10-dinaphthylanthracene, 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), and 4,7-diphenyl-1,10-phenanthroline (Bphe). n), 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), 4-(naphthyl-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (tBu-PBD), bis(2-methyl-8-hydroxyquinoline-N1,O8)-(1,1'-biphenyl-4-hydroxy)aluminum (BAlq), bis(benzoquinoline-10-hydroxy)beryllium (Bebq2), 9,10-bis(naphthyl-2-yl)anthracene (ADN), or mixtures thereof, without limitation. The thickness of the electron transport layer (ETL) can be approximately to approximately Within a certain range, and can be, for example, approximately to approximately Within the range described above, if the thickness of the electron transport layer (ETL) meets any of these ranges, appropriate or satisfactory electron transport properties can be obtained without a significant increase in the driving voltage.

[0211] If the electron transport region (ETR) includes an electron injection layer (EIL), the EIL may include metal halides such as LiF, NaCl, CsF, RbCl, RbI, and / or CuI, lanthanides such as Yb, metal oxides such as Li₂O and BaO, and / or lithium 8-hydroxyquinoline (Liq). However, embodiments of this disclosure are not limited thereto. The EIL may also be formed using a mixture of an electron injection material and an insulating organometallic salt. The insulating organometallic salt may be a material with a band gap of about 4 eV or greater. In some embodiments, the insulating organometallic salt may include, for example, metal acetates, metal benzoates, metal acetoacetates, metal acetylacetonates, and / or metal stearates. The thickness of the EIL may be approximately [missing information - likely related to thickness]. to approximately Within the range, or within approximately to approximately Within the range. If the thickness of the electron injection layer (EIL) meets any of the above ranges, appropriate or satisfactory electron injection properties can be obtained without a significant increase in the driving voltage.

[0212] The electron transport region (ETR) may include a hole blocking layer (HBL) as described above. The hole blocking layer (HBL) may include, for example, at least one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and 4,7-diphenyl-1,10-phenanthroline (Bphen). However, embodiments of this disclosure are not limited thereto.

[0213] The second electrode EL2 is provided on the electron transport region ETR. The second electrode EL2 can be a common electrode or a cathode. The second electrode EL2 can be a transmission electrode, a transmission-reflection electrode (e.g., a semi-transmission electrode), or a reflection electrode. If the second electrode EL2 is a transmission electrode, it can comprise a transparent metal oxide, such as ITO, IZO, ZnO, ITZO, etc.

[0214] If the second electrode EL2 is a transmissive / reflective electrode (e.g., a semi-transmissive electrode) or a reflective electrode, then the second electrode EL2 may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, their compounds or mixtures thereof (e.g., a mixture of Ag and Mg). The second electrode EL2 may have a multilayer structure, comprising a reflective or transmissive / reflective layer formed using the above-described materials and a transparent conductive layer formed using ITO, IZO, ZnO, ITZO, etc.

[0215] In some implementations, the second electrode EL2 may be coupled to an auxiliary electrode. If the second electrode EL2 is coupled to the auxiliary electrode, the resistance of the second electrode EL2 may be reduced.

[0216] In some embodiments, the organic electroluminescent device 10 may further include a buffer layer between the emitter layer (EML) and the electron transport region (ETR). The buffer layer can control the concentration of excitons generated in the emitter layer (EML). For example, the buffer layer may include a portion of the material used in the emitter layer (EML). The buffer layer may include the host material in the material used in the emitter layer (EML). Depending on the combination of host and dopant materials included in the emitter layer (EML), the lowest triplet excitation level of the buffer layer material can be controlled to be the lowest triplet excitation level of the second dopant or higher, or the lowest triplet excitation level of the second dopant or lower.

[0217] In some embodiments, the capping layer CPL may be further included on the second electrode EL2 of the organic electroluminescent device 10 of the embodiment. The capping layer CPL may include an organic layer and / or an inorganic layer. The capping layer CPL may be a single layer of organic or inorganic layers, or a stacked layer of organic and inorganic layers in sequence. The capping layer CPL may have a refractive index of about 1.6 or greater in the wavelength range of about 560 nm to about 600 nm. The capping layer CPL may include an amine compound of CPL1 or CPL2 below.

[0218]

[0219] In some embodiments, the capping layer CPL may include N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4'-diamine (α-NPD), NPB, TPD, m-MTDATA, Alq3, CuPc, N4,N4,N4',N4'-tetra(biphenyl-4-yl)biphenyl-4,4'-diamine (TPD15), 4,4',4”-tris(carbazole-9-yl)triphenylamine (TCTA), etc. The capping layer CPL may include silicon nitrides, aluminum nitrides, zirconium nitrides, titanium nitrides, hafnium nitrides, tantalum nitrides, silicon oxides, aluminum oxides, titanium oxides, tin oxides, cerium oxides, silicon oxynitrides, etc.

[0220] The organic electroluminescent device 10 according to embodiments of the present disclosure includes the fused polycyclic compound of the embodiment in the emission layer EML between the first electrode EL1 and the second electrode EL2, and can exhibit high emission efficiency properties. Furthermore, the fused polycyclic compound of the embodiment can be a thermally activated delayed fluorescence dopant, and the emission layer EML can include the fused polycyclic compound of the embodiment, thereby emitting thermally activated delayed fluorescence and exhibiting high emission efficiency.

[0221] In some embodiments, the fused polycyclic compound of the embodiment may be included as a material for the organic electroluminescent device 10 in an organic layer other than the emitting layer EML. For example, the organic electroluminescent device 10 according to embodiments of the present disclosure may include the fused polycyclic compound in at least one organic layer between the first electrode EL1 and the second electrode EL2, or in the capping layer CPL on the second electrode EL2.

[0222] The fused polycyclic compound of the embodiment comprises three boron atoms and has a structure in which seven aromatic rings are connected by three or four boron atoms and five heteroatoms, and has a relatively low energy difference (ΔE) between the lowest triplet excitation level (T1 level) and the lowest singlet excitation level (S1 level) compared with existing compounds. ST If a fused polycyclic compound is used as a material for the emitter layer EML, the efficiency of the organic electroluminescent device 10 can be improved.

[0223] The compounds and organic electroluminescent devices according to embodiments of the present disclosure will be further explained below with reference to embodiments and comparative embodiments. The following embodiments are merely illustrative to aid in understanding the subject matter of the present disclosure, and the scope of the disclosure is not limited thereto.

[0224] Example

[0225] 1. Synthesis of fused polycyclic compounds

[0226] First, the synthesis methods of the fused polycyclic compounds according to the embodiments will be further explained with reference to the synthesis methods of compounds 1, 6, 14, 22, 25 and 27. Furthermore, the synthesis methods of the fused polycyclic compounds explained below are merely embodiments, and the synthesis methods of the fused polycyclic compounds according to the embodiments of this disclosure are not limited thereto.

[0227] (1) Synthesis of compound 1

[0228] The fused polycyclic compound 1 according to the embodiments can be synthesized, for example, by the reaction scheme shown and described below.

[0229] Reaction 1

[0230]

[0231] Synthetic intermediate 1-I-1

[0232] Under a nitrogen atmosphere, 1,3-dibromo-5-chlorobenzene (1 eq), diphenylamine (2.2 eq), Pd₂dba₃ (0.05 eq), PtBu₃ (0.1 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 120 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the organic layer was dried over anhydrous magnesium sulfate, followed by drying under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 1-I-1 (yield 85%).

[0233] Synthetic intermediate 1-I-2

[0234] Under a nitrogen atmosphere, intermediate 1-I-1 (1 eq), aniline (2 eq), Pd2dba3 (0.05 eq), PtBu3 (0.1 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 120 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the organic layer was dried over anhydrous magnesium sulfate, followed by drying under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 1-I-2 (yield 90%).

[0235] Reaction 2

[0236]

[0237] Synthetic intermediate 1-1

[0238] Under a nitrogen atmosphere, 1,3-dibromo-5-fluorobenzene (1 eq), phenol (1.2 eq), and K3PO4 (3 eq) were dissolved in N,N-dimethylformamide (DMF) and stirred at approximately 160 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product was then separated by column chromatography to obtain intermediate 1-1 (yield 80%).

[0239] Synthetic intermediate 1-2

[0240] Under a nitrogen atmosphere, intermediate 1-1 (1 eq), diphenylamine (1 eq), Pd2dba3 (0.05 eq), PtBu3 (0.1 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 110 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 1-2 (yield 80%).

[0241] Synthetic intermediates 1-3

[0242] Under a nitrogen atmosphere, intermediates 1-2 (1 eq), aniline (2 eq), Pd2dba3 (0.05 eq), PtBu3 (0.1 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 110 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 1-3 (yield 85%).

[0243] Synthetic intermediates 1-4

[0244] Under a nitrogen atmosphere, intermediates 1-3 (1 eq), 1,3-dibromobenzene (1.5 eq), Pd₂dba₃ (0.05 eq), PtBu₃ (0.1 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 110 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 1-4 (yield 80%).

[0245] Synthetic intermediates 1-5

[0246] Under a nitrogen atmosphere, intermediates 1-4 (1 eq), 1-I-2 (1 eq), Pd2dba3 (0.05 eq), PtBu3 (0.1 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 110 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 1-5 (yield 55%).

[0247] Synthetic intermediates 1-6

[0248] Under a nitrogen atmosphere, intermediates 1-5 (1 eq) and boron tribromide (6 eq) were dissolved in o-dichlorobenzene (o-DCB), and stirred at approximately 160 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate, followed by drying under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediates 1-6 (yield 7%).

[0249] Synthetic compound 1

[0250] Under a nitrogen atmosphere, intermediates 1-6 (1 eq) and boron tribromide (3 eq) were dissolved in o-dichlorobenzene (o-DCB) and stirred at about 0 °C for about 1 hour. After cooling, phenyl magnesium bromide (1.5 eq) was added dropwise to the resulting solution, and the mixture was stirred at room temperature for about 12 hours. The reaction product was then washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product thus obtained was then separated by column chromatography to obtain compound 1 (yield 7%).

[0251] (2) Synthesis of compound 6

[0252] The fused polycyclic compound 6 according to the embodiments can be synthesized, for example, by the reaction scheme shown and described below.

[0253] Reaction 3

[0254]

[0255] Synthetic intermediate 6-I-1

[0256] Under a nitrogen atmosphere, intermediate 1-I-1 (1 eq), 2,6-dimethylaniline (2 eq), Pd2dba3 (0.05 eq), PtBu3 (0.1 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 110 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 6-I-1 (70% yield).

[0257] Reaction 4

[0258]

[0259] Synthetic intermediate 6-1

[0260] Under a nitrogen atmosphere, 3,5-dibromophenol (1 eq), diphenylamine (2.2 eq), Pd₂dba₃ (0.1 eq), PtBu₃ (0.2 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 110 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product was then separated by column chromatography to obtain intermediate 6-1 (yield 80%).

[0261] Synthetic intermediate 6-2

[0262] Under a nitrogen atmosphere, intermediate 6-1 (1 eq), 1-bromo-3-fluorobenzene (1.2 eq), and K3PO4 (3 eq) were dissolved in N,N-dimethylformamide (DMF) and stirred at approximately 160 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 6-2 (70% yield).

[0263] Synthetic intermediate 6-3

[0264] Under a nitrogen atmosphere, intermediates 6-2 (1 eq), 6-I-1 (1 eq), Pd2dba3 (0.1 eq), PtBu3 (0.2 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 110 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the organic layer was dried over anhydrous magnesium sulfate, followed by drying under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 6-3 (yield 50%).

[0265] Synthetic intermediate 6-4

[0266] Under a nitrogen atmosphere, intermediate 6-3 (1 eq) and boron tribromide (6 eq) were dissolved in o-dichlorobenzene (o-DCB), and the mixture was stirred at approximately 160 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 6-4 (yield 5%).

[0267] Synthetic compound 6

[0268] Under a nitrogen atmosphere, intermediate 6-4 (1 eq) and boron tribromide (3 eq) were dissolved in o-dichlorobenzene (o-DCB) and stirred at about 0 °C for about 1 hour. Then, phenyl magnesium bromide (1.5 eq) was added dropwise to the resulting solution, and the mixture was stirred at room temperature for about 12 hours. The reaction product was then washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product thus obtained was then separated by column chromatography to give compound 6 (yield 5%).

[0269] (3) Synthesize compound 14

[0270] The fused polycyclic compound 14 according to the embodiments can be synthesized, for example, by the reaction scheme shown and described below.

[0271] Reaction 5

[0272]

[0273] Synthetic intermediate 14-1

[0274] Under a nitrogen atmosphere, intermediates 1-2 (1 eq), 2,6-dimethylaniline (2 eq), Pd2dba3 (0.05 eq), PtBu3 (0.1 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 110 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product was then separated by column chromatography to obtain intermediate 14-1 (yield 80%).

[0275] Synthetic intermediate 14-2

[0276] Under a nitrogen atmosphere, intermediate 14-1 (1 eq), 1,3-dibromobenzene (2 eq), Pd2dba3 (0.05 eq), PtBu3 (0.1 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 110 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 14-2 (70% yield).

[0277] Synthetic intermediate 14-3

[0278] Under a nitrogen atmosphere, intermediates 14-2 (1 eq), 1-I-2 (1.2 eq), Pd2dba3 (0.05 eq), PtBu3 (0.1 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 110 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 14-3 (65% yield).

[0279] Synthetic intermediate 14-4

[0280] Under a nitrogen atmosphere, intermediate 14-3 (1 eq) and boron tribromide (6 eq) were dissolved in o-dichlorobenzene (o-DCB), and the mixture was stirred at approximately 160 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 14-4 (yield 6%).

[0281] Synthetic compound 14

[0282] Under a nitrogen atmosphere, intermediate 14-4 (1 eq) and boron tribromide (3 eq) were dissolved in o-dichlorobenzene (o-DCB) and stirred at about 0 °C for about 1 hour. Then, 2,4,6-trimethylphenyl magnesium bromide (1.5 eq) was added dropwise to the resulting solution, and the mixture was stirred at room temperature for about 12 hours. The reaction product was then washed three times with ethyl acetate and water, and the organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product thus obtained was then separated by column chromatography to obtain compound 14 (yield 4%).

[0283] (4) Synthesize compound 22

[0284] The fused polycyclic compound 22 according to the embodiments can be synthesized, for example, by the reaction scheme shown and described below.

[0285] Reaction 6

[0286]

[0287] Synthetic intermediate 22-1

[0288] Under a nitrogen atmosphere, 1-bromo-3,5-difluorobenzene (1 eq), diphenylamine (1.2 eq), Pd₂dba₃ (0.1 eq), PtBu₃ (0.2 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 110 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product was then separated by column chromatography to obtain intermediate 22-1 (yield 85%).

[0289] Synthetic intermediate 22-2

[0290] Under a nitrogen atmosphere, intermediate 22-1 (1.1 eq), phenol (1 eq), and K3PO4 (2 eq) were dissolved in N,N-dimethylformamide (DMF) and stirred at approximately 160 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 22-2 (75% yield).

[0291] Synthetic intermediate 22-3

[0292] Under a nitrogen atmosphere, intermediate 22-2 (1 eq), 3-bromophenol (1.2 eq), and K3PO4 (3 eq) were dissolved in N,N-dimethylformamide (DMF) and stirred at approximately 160 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the organic layer was dried over anhydrous magnesium sulfate, followed by drying under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 22-3 (70% yield).

[0293] Synthetic intermediate 22-4

[0294] Under a nitrogen atmosphere, intermediates 22-3 (1 eq), 1-I-2 (1.2 eq), Pd2dba3 (0.1 eq), PtBu3 (0.2 eq), and NaOtBu (3 eq) were dissolved in toluene and stirred at approximately 110 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 22-4 (65% yield).

[0295] Synthetic intermediate 22-5

[0296] Under a nitrogen atmosphere, intermediate 22-4 (1 eq) and boron tribromide (6 eq) were dissolved in o-dichlorobenzene (o-DCB), and stirred at approximately 160 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the organic layer was dried over anhydrous magnesium sulfate, followed by drying under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 22-5 (yield 3%).

[0297] Synthetic compound 22

[0298] Under a nitrogen atmosphere, intermediate 22-5 (1 eq) and boron tribromide (3 eq) were dissolved in o-dichlorobenzene (o-DCB) and stirred at about 0 °C for about 1 hour. Then, phenyl magnesium bromide (1.5 eq) was added dropwise to the resulting solution, and the mixture was stirred at room temperature for about 12 hours. The reaction product was then washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product thus obtained was then separated by column chromatography to obtain compound 22 (yield 5%).

[0299] (5) Synthesize compound 25

[0300] The fused polycyclic compound 25 according to the embodiments can be synthesized, for example, by the reaction scheme shown and described below.

[0301] Reaction 7

[0302]

[0303] Synthetic intermediate 25-1

[0304] Under a nitrogen atmosphere, intermediates 22-3 (1 eq), 6-1 (1 eq), CuI (0.1 eq), and 1,10-phenanthroline (0.2 eq) were dissolved in N,N-dimethylformamide (DMF) and stirred at approximately 160 °C for about 12 hours. After cooling, the reaction products were washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 25-1 (yield 55%).

[0305] Synthetic intermediate 25-2

[0306] Under a nitrogen atmosphere, intermediate 25-1 (1 eq) and boron tribromide (6 eq) were dissolved in o-dichlorobenzene (o-DCB), and stirred at approximately 160 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate, followed by drying under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 25-2 (yield 3%).

[0307] Synthetic compound 25

[0308] Under a nitrogen atmosphere, intermediate 25-2 (1 eq) and boron tribromide (3 eq) were dissolved in o-dichlorobenzene (o-DCB) and stirred at about 0 °C for about 1 hour. Then, phenyl magnesium bromide (1.5 eq) was added dropwise to the resulting solution, and the mixture was stirred at room temperature for about 12 hours. The reaction product was then washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product thus obtained was then separated by column chromatography to obtain compound 25 (yield 4%).

[0309] (6) Synthetic compound 27

[0310] The fused polycyclic compound 27 according to the embodiments can be synthesized, for example, by the reaction scheme shown and described below.

[0311] Reaction 8

[0312]

[0313] Synthetic intermediate 27-1

[0314] Under a nitrogen atmosphere, intermediate 25-2 (2.2 eq), resorcinol (1 eq), and K3PO4 (5 eq) were dissolved in N,N-dimethylformamide (DMF) and stirred at approximately 160 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 27-1 (yield 45%).

[0315] Synthetic intermediate 27-2

[0316] Under a nitrogen atmosphere, intermediate 27-1 (1 eq) and boron tribromide (6 eq) were dissolved in o-dichlorobenzene (o-DCB), and the mixture was stirred at approximately 160 °C for about 12 hours. After cooling, the reaction product was washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product obtained was then separated by column chromatography to obtain intermediate 27-2 (yield 2%).

[0317] Synthetic compound 27

[0318] Under a nitrogen atmosphere, intermediate 27-2 (1 eq) and boron tribromide (3 eq) were dissolved in o-dichlorobenzene (o-DCB) and stirred at about 0 °C for about 1 hour. Then, 2,6-dimethylphenyl magnesium bromide (1.5 eq) was added dropwise to the resulting solution, and the mixture was stirred at room temperature for about 12 hours. The reaction product was then washed three times with ethyl acetate and water, and the resulting organic layer was dried over anhydrous magnesium sulfate and then dried under reduced pressure. The crude product thus obtained was then separated by column chromatography to obtain compound 27 (yield 4%).

[0319] 2. Evaluate the energy levels of fused polycyclic compounds.

[0320] Evaluate the energy levels of compounds 1, 6, 14, 22, 25 and 27 in the examples below, as well as the energy levels of the comparative compound C1.

[0321] The following are examples of compounds and comparative compounds used to evaluate energy levels, etc.

[0322]

[0323] Table 1 below shows the HOMO level, LUMO level, lowest singlet excitation level (S1 level), lowest triplet excitation level (T1 level), dipole moment, oscillator strength (OSC), and ΔE for compounds 1, 6, 14, 22, 25, and 27 (which are example compounds) and the comparative compound C1. ST In Table 1, the energy level values ​​were calculated using the non-empirical molecular orbital method; specifically, they were calculated using the Gaussian 09 software package from Gaussian Co., where the calculations were performed using density functional theory (DFT) with B3LYP mixed functionals and the 6-31G(d) basis set (B3LYP / 6-31G(d)). In Table 1, ΔE ST The difference between the lowest singlet excitation level (S1 level) and the lowest triplet excitation level (T1 level) is shown.

[0324] Table 1

[0325]

[0326]

[0327] As can be seen from Table 1, compounds 1, 6, 14, 22, 25, and 27 (which are examples compounds) exhibit higher oscillator strength values ​​than the comparative compound C1. It can also be seen that compounds 1, 6, 14, 22, 25, and 27 (which are examples compounds) all exhibit relatively small ΔE values ​​of approximately 0.33 eV or less. ST With high values ​​for both light absorption and oscillator strength, it can be used as a thermally activated delayed fluorescence dopant material to improve light absorption characteristics.

[0328] 3. Fabrication and evaluation of organic electroluminescent devices including fused polycyclic compounds.

[0329] Manufacturing organic electroluminescent devices

[0330] The organic electroluminescent devices of the embodiments, which include fused polycyclic compounds of the embodiments in the emitter layer, are manufactured by the following method. The organic electroluminescent devices of Examples 1 to 12 are manufactured using fused polycyclic compounds 1, 6, 14, 22, and 27 (which are example compounds) as dopant materials and host materials of the emitter layer. Comparative Examples 1 to 5 correspond to organic electroluminescent devices manufactured using comparative compounds C1 to C5 as dopant materials of the emitter layer.

[0331] To form the first electrode, ITO is patterned on the glass substrate to approximately [size missing]. The thickness was increased to form the first electrode, and the electrode was ultrasonically cleaned for approximately 5 minutes using isopropanol and pure water, respectively, and then cleaned by irradiation with ultraviolet light and ozone for approximately 30 minutes. On a glass substrate on which ITO was formed, NPD was vacuum deposited to a thickness of approximately [missing information]. The thickness is adjusted to form a hole injection layer, and then an amine compound or hole transport compound TCTA, represented by formula HT1 or HT9 below, is vacuum deposited to a thickness of approximately [thickness value missing]. The thickness is such that a hole transport layer is formed. On the hole transport layer, mCP and compounds of the embodiments of this disclosure, or two types (or kinds) of compounds of the embodiments of this disclosure, or mCP and a comparative compound, are simultaneously deposited at a weight ratio of 99:1 to form a thickness of approximately [missing information]. The emission layer. Then, the compound TSPO1 for the electron transport layer is formed to approximately [amount missing]. The thickness was determined, and the compound TPBi for the electron injection layer was deposited to approximately [amount missing]. The thickness. On the electron-injected layer, alkali metal halide LiF is deposited to approximately [thickness value missing]. The thickness, and Al vacuum deposited to approximately The thickness is adjusted to form the LiF / Al second electrode. Then, on the second electrode, a layer with a thickness of approximately [missing information] is formed using CPL1. The capping layer is used to manufacture organic electroluminescent devices.

[0332] The compounds used to manufacture the organic electroluminescent devices of the examples and comparative examples are shown below.

[0333]

[0334]

[0335] Evaluation of the properties of organic electroluminescent devices

[0336] Table 2 shows the evaluation results of the organic electroluminescent devices of Examples 1 to 12 and Comparative Examples 1 to 5. Table 2 compares the driving voltage and emission efficiency of the organic electroluminescent devices thus fabricated.

[0337] In the property evaluation results of the examples and comparative examples shown in Table 2, voltage and current densities were measured using a source meter (Keithley Instrument Co., 2400 series), and emission efficiency was measured using an external quantum efficiency measurement device (Hamamatsu Photonics Co., 9920-12). For the evaluation of the maximum external quantum efficiency, luminance / current density was measured using a luminance photometer calibrated to wavelength sensitivity, and the maximum external quantum efficiency was converted by assuming the introduction of an angular luminance distribution (Lambertian) on a perfectly diffuse reflective surface. The drive voltage and emission efficiency are shown relative to approximately 10 mA / cm². 2 The current efficiency value of the current density.

[0338] Table 2

[0339]

[0340]

[0341] Referring to the results in Table 2, it can be seen that, compared with the comparative examples, the embodiments of the organic electroluminescent device using the fused polycyclic compound as the emission layer material according to the present disclosure exhibit lower driving voltage values ​​and relatively higher emission efficiency. The compound of the embodiments exhibits TADF properties using multiple resonance phenomena due to the fused aromatic rings (including three or four boron atoms) forming the fused rings, and includes a structure in which seven aromatic rings are connected via three or four boron atoms and five heteroatoms, and exhibits multiple resonances in a wide plate-shaped framework when compared with the comparative compound C1. Therefore, the organic electroluminescent device of the embodiments exhibits improved emission efficiency when compared with the organic electroluminescent device of the comparative examples.

[0342] In comparative compound C2, although it includes an aromatic ring forming a fused ring, it includes two boron atoms, and when compared with the compound of the examples, the multiple resonance effect due to the plate-like framework is reduced. Therefore, it can be seen that, when compared with the device of the examples, the device of Comparative Example 2, which includes comparative compound C2 as an emitter layer dopant, exhibits an increased driving voltage and a reduced emission efficiency.

[0343] In comparative compounds C3 to C5, an aromatic ring forming a fused ring and three or more boron atoms are included. However, unlike the present disclosure, the seven aromatic rings do not have the optimized structure connected via three or four boron atoms and five heteroatoms, and the multiple resonance effect is reduced compared to the compound of the examples. Therefore, it can be seen that, when compared with the device of the examples, the devices of comparative examples 3 to 5, which include comparative compounds C3 to C5 as emitter layer dopants, exhibit increased driving voltage and reduced emission efficiency.

[0344] The fused polycyclic compounds of the embodiments include a structure in which seven aromatic rings are linked by three or four boron atoms and five heteroatoms, exhibiting high oscillator strength values ​​and small ΔE. ST The fused polycyclic compounds described in this embodiment can be used as dopant materials for the emitting layer of organic electroluminescent devices and can improve device efficiency.

[0345] The organic electroluminescent device of the embodiments includes the fused polycyclic compound of the embodiments and can exhibit improved emission efficiency. Furthermore, the organic electroluminescent device of the embodiments includes the fused polycyclic compound of the embodiments as a material for the emission layer and can achieve high emission efficiency in the blue light wavelength region.

[0346] The organic electroluminescent device of the embodiment can exhibit improved device characteristics with low driving voltage and high efficiency.

[0347] The fused polycyclic compound of the embodiment may be included in the emitting layer of the organic electroluminescent device and may help improve the efficiency of the organic electroluminescent device.

[0348] Although exemplary embodiments of this disclosure have been described herein, it should be understood that this disclosure is not limited to these exemplary embodiments, but rather various changes and modifications can be made by those skilled in the art within the spirit and scope of this disclosure as claimed above.

Claims

1. An organic electroluminescent device comprising: a first electrode; a second electrode facing the first electrode; and a plurality of organic layers between the first electrode and the second electrode, wherein at least one of the plurality of organic layers comprises a fused polycyclic compound represented by the following Formula 2, and at least one of the plurality of organic layers comprises an amine compound represented by the following Formula a: Formula 2 wherein, in Formula 2, Y1and Y2are each independently BAr1, X1to X4are each independently NR a , O or S, R a R is hydrogen, halogen, -OR, -SR, -NRR', -NRR'2, -CN, -C(O)R, -C(O)OR, -C(O)NRR', -S(O)R, -S Ar1is a substituted or unsubstituted aryl group of 6 to 20 ring-forming carbon atoms, R1to R6are each independently a hydrogen atom, a deuterium atom, a halogen atom, a phosphine oxide group, a cyano group, a substituted or unsubstituted amine group, a substituted or unsubstituted silyl group, or a substituted or unsubstituted alkyl group of 1 to 20 carbon atoms, n1to n4are each independently an integer in the range of 0 to 4, n5is an integer in the range of 0 to 3, n6is an integer in the range of 0 to 2, and one of m1and m2is 1, and the other is 0, wherein the case where m1is 0 means that the benzene ring having a substituent R1is not connected to the benzene ring having X1and X2via Y1, and wherein the case where m1is 1 means that the benzene ring having a substituent R1is connected to the benzene ring having X1and X2via Y1, wherein the case where m2is 0 means that the benzene ring having a substituent R2is not connected to the benzene ring having X1and X2via Y2, and wherein the case where m2is 1 means that the benzene ring having a substituent R2is connected to the benzene ring having X1and X2via Y2, Formula a wherein, in Formula a, the term "substituted or unsubstituted" means unsubstituted or substituted with at least one substituent selected from the group consisting of a deuterium atom, a halogen atom, a cyano group, a nitro group, an amine group, a silyl group, an oxygen group, a sulfur group, a sulfinyl group, a sulfonyl group, a carbonyl group, a boron group, a phosphine oxide group, a phosphine sulfide group, an alkyl group, an alkenyl group, a hydrocarbyl group, an aryl group, and a heterocyclic group. Ar a to Ar c each independently substituted or unsubstituted aryl of 6 to 20 ring-forming carbon atoms or substituted or unsubstituted heteroaryl of 2 to 20 ring-forming carbon atoms, 2. The organic electroluminescent device according to claim 1, wherein the plurality of organic layers comprise: a hole transport zone on the first electrode; an emission layer on the hole transport zone; and an electron transport zone on the emission layer, and the emission layer comprises the fused polycyclic compound represented by the above Formula 2.

3. The organic electroluminescent device according to claim 2, wherein the emission layer emits delayed fluorescence.

4. The organic electroluminescent device according to claim 2, wherein the emission layer is a delayed fluorescence emission layer comprising a host and a dopant, and the dopant comprises the fused polycyclic compound represented by the above Formula 2.

5. The organic electroluminescent device according to claim 2, wherein the emission layer is a delayed fluorescence emission layer comprising a host and a dopant, and the host comprises the fused polycyclic compound represented by the above Formula 2.

6. The organic electroluminescent device according to claim 2, wherein the hole transport zone comprises: a hole injection layer on the first electrode; and a hole transport layer on the hole injection layer, and the hole transport layer comprises the amine compound represented by the above Formula a. ​ ​ ​ 7.The organic electroluminescence device according to claim 1, further comprising a capping layer on the second electrode, the capping layer having a refractive index of 1.6 or more. 8.The organic electroluminescence device according to claim 1, wherein the fused polycyclic compound represented by the above formula 2 is represented by the following formula 3-1 and formula 3-2: Formula 3-1 Formula 3-2 wherein In formula 3-1 and formula 3-2, R7 and R8 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a phosphine oxide group, a cyano group, a substituted or unsubstituted amine group, a substituted or unsubstituted silyl group, or a substituted or unsubstituted alkyl group of 1 to 20 carbon atoms, n7 and n8 are each independently an integer in a range of 0 to 5, and X1to X4, R a , R1to R6and n1to n6are the same as defined in Formula 2. 9.The organic electroluminescence device according to claim 1, wherein the fused polycyclic compound represented by the above formula 2 is represented by the following formula 4-1 to formula 4-6: Formula 4-1 Formula 4-2 Formula 4-3 Formula 4-4 Formula 4-5 Formula 4-6 wherein, In formula 4-1 to 4-6, R 11 to R 14 each independently is a hydrogen atom, a deuterium atom, a halogen atom, a phosphine oxide group, a cyano group, a substituted or unsubstituted amine group, a substituted or unsubstituted silyl group, or a substituted or unsubstituted alkyl group of 1 to 20 carbon atoms, n 11 to n 14 each independently an integer in the range of 0 to 5, and Y1, Y2, Ar1, R1 to R6, m1, m2, and n1 to n6 are the same as defined in formula 2. 10.The organic electroluminescence device according to claim 1, wherein the fused polycyclic compound represented by the above formula 2 is represented by the following formula 5: Formula 5 wherein In formula 5, Ar2 and Ar3 are each independently a substituted or unsubstituted aryl group of 6 to 30 ring-forming carbon atoms, and X1to X4, R a Y1, Y2, Ar1, m1and m2are the same as defined in Formula 2. 11.The organic electroluminescence device according to claim 1, wherein in formula 2, when X1to X4are each independently NR a a is a substituted or unsubstituted phenyl group.​ 12.The organic electroluminescence device according to claim 1, wherein in formula 2, Ar1 is a substituted or unsubstituted phenyl group. 13.The organic electroluminescence device according to claim 1, wherein in formula 2, when m1 is 1, X1 is O or S, and when m2 is 1, X2 is O or S. 14.The organic electroluminescence device according to claim 1, wherein the fused polycyclic compound comprises at least one selected from the group of compounds represented in the following [Compound Group 1]: [Compound Group 1]

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