Organic electroluminescent device and polycyclic compound for organic electroluminescent device

Abstract

To provide an organic electroluminescence device including a thermally activated delayed fluorescent material, and a polycyclic compound used as a thermally activated delayed fluorescent material.SOLUTION: Provided is a polycyclic compound represented by formula 1. In formula 1, Ar1 and Ar2 independently represent a substituted or unsubstituted C6-30 aryl group or the like; R1-R8 independently represent H, a substituted or unsubstituted amino group, a substituted or unsubstituted aryl group with 6-30 ring forming carbon atoms, or the like, or R1-R8 bind to each other to form a ring, and at least two of R1-R8 have an amino group with two substituted or unsubstituted aryl groups or the like being substituted.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an organic electroluminescent device and a polycyclic compound used therein. [Background technology]

[0002] Recently, organic electroluminescence display devices have been actively developed as image display devices. Unlike liquid crystal display devices, organic electroluminescence display devices are so-called self-luminous display devices that realize display by causing holes and electrons injected from a first electrode and a second electrode to recombine in a light-emitting layer, thereby causing a light-emitting material containing an organic compound in the light-emitting layer to emit light.

[0003] In order to apply organic electroluminescent devices to display devices, there is a demand for lower driving voltages, higher luminous efficiency, and longer life for the organic electroluminescent devices, and there is a continuous demand for the development of materials for organic electroluminescent devices that can stably achieve these demands.

[0004] In particular, in order to realize highly efficient organic electroluminescent devices, technologies related to phosphorescence emission that utilizes the energy of triplet states and delayed fluorescence emission that utilizes the phenomenon in which singlet excitons are generated by the collision of triplet excitons (TTA) have been developed recently, and development of thermally activated delayed fluorescence (TADF) materials that utilize the delayed fluorescence phenomenon is also underway. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2015 / 102118 [Patent Document 2] International Publication No. 2018 / 047639 [Patent Document 3] International Publication No. 2016 / 152544 [Patent Document 4] International Publication No. 2017 / 188111 [Patent Document 5] International Publication No. 2017 / 138526 [Patent Document 6] International Publication No. 2017 / 126443 [Patent Document 7] US Patent Application Publication No. 2018 / 0069182 [Patent Document 8] International Publication No. 2011 / 143563 [Patent Document 9] China Patent Application Publication No. 107501311 [Patent Document 10] China Patent Application Publication No. 107417715 [Patent Document 11] China Patent Application Publication No. 107266484 [Patent Document 12] China Patent Application Publication No. 106467553 [Patent Document 13] China Patent Application Publication No. 106467554 [Patent Document 14] International Publication No. 2017 / 195669 [Patent Document 15] JP 2017-126606 A [Patent Document 16] International Publication No. 2016 / 152418 [Patent Document 17] US Patent Application Publication No. 2011 / 0278556 [Patent Document 18] DE 19648256 A1 [Patent Document 19] Korean Patent Publication No. 10-2018-0046851 [Patent Document 20] JP 2018-061029 A [Patent Document 21] JP 2018-061030 A [Patent Document 22] JP 2018-061028 A [Patent Document 23] International Publication No. 2018 / 062278 [Patent Document 24] US Patent Application Publication No. 2014 / 0014922 [Patent Document 25] US Patent Application Publication No. 2011 / 0279019 [Patent Document 26] Korean Patent No. 10-1785755 [Patent Document 27] Korean Patent Publication No. 10-2014-0103842 [Patent Document 28] Korean Patent No. 10-0915271 [Patent Document 29] JP 2016-036022 A [Patent Document 30] Patent No. 4428772 [Patent Document 31] Patent No. 4810687 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide an organic electroluminescent device having a long life and high efficiency, and a polycyclic compound used therein.

[0007] Another object of the present invention is to provide an organic electroluminescent device including a thermally activated delayed fluorescent luminescent material and a polycyclic compound used as the thermally activated delayed fluorescent luminescent material. [Means for solving the problem]

[0008] In one embodiment, there is provided an organic electroluminescent device comprising a first electrode, a hole transport region disposed on the first electrode, an emissive layer disposed on the hole transport region, an electron transport region disposed on the emissive layer, and a second electrode disposed on the electron transport region, wherein the emissive layer comprises a polycyclic compound represented by Chemical Formula 1 below. [ka] In Chemical Formula 1, Ar 1 and Ar 2 each independently represents a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms; R 1 ~R 8 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted amino group, a cyano group, a boron group, a carbonyl group, a silyl group, an oxy group, a phosphine oxide group, a phosphine sulfide group, a substituted or unsubstituted thiol group, a sulfonyl group, a substituted or unsubstituted alkyl group having from 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group having from 7 to 30 carbon atoms, a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms, or R 1 ~R 8 are bonded together to form a ring, and R 1 ~R 8 At least two of these are represented by the following chemical formula 2. [ka] In Chemical Formula 2, L is a single bond, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroarylene group having 2 to 30 ring carbon atoms, or is bonded to an adjacent group to form a ring, and Ar 3 and Ar 4 each independently represents a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms, or is bonded to an adjacent group to form a ring.

[0009] The light-emitting layer emits delayed fluorescence.

[0010] The light-emitting layer is a delayed fluorescent light-emitting layer containing a host and a dopant, and the dopant is a polycyclic compound.

[0011] The light-emitting layer is a thermally activated delayed fluorescent light-emitting layer that emits blue light.

[0012] In Chemical Formula 1, Ar 1 is represented by the following chemical formula 3. [ka] In Chemical Formula 3, V 1 ~V 5 are each independently N or CR 9 and R 9 is a hydrogen atom, a deuterium atom, a halogen atom, a boron group, a substituted or unsubstituted amino group, a cyano group, a carbonyl group, an oxy group, a silyl group, a thiol group, a phosphine oxide group, a phosphine sulfide group, a substituted or unsubstituted alkyl group having from 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having from 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having from 7 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms, or is bonded to an adjacent group to form a ring.

[0013] In Chemical Formula 3, V 1 ~V 5 At least one of them is CR 10 and R 10 is a substituted or unsubstituted alkyl group having 2 to 20 carbon atoms.

[0014] In Chemical Formula 2, Ar 3 represents a substituted aryl group having from 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms.

[0015] In Chemical Formula 1, R 1 ~R 4 At least one of the formulas is represented by formula 2, 5 ~R 8 At least one of the above is represented by Chemical Formula 2.

[0016] Chemical Formula 1 is represented by Chemical Formula 4 below. [ka]

[0017] In Chemical Formula 4, L' is a single bond, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring carbon atoms; Ar 3 ' and Ar 4 ' are each independently a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 30 ring carbon atoms, or are bonded to an adjacent group to form a ring, and Ar 1 ~Ar 4 , R 1 , R 3 ~R 6 , R 8 and L are as defined in Chemical Formula 1 and Chemical Formula 2.

[0018] In Chemical Formula 4, at least one of L and L' is a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring carbon atoms.

[0019] In Chemical Formula 4, L and L' are each independently a single bond.

[0020] The compound represented by Chemical Formula 1 is any one of the compounds shown in the first compound group below. [First compound group] [ka] [ka] [ka] [ka] [ka]

[0021] In one embodiment, a polycyclic compound represented by Formula 1 is provided. In addition, in an organic electroluminescent device according to an embodiment of the present invention, the first electrode and the second electrode may each independently include any one selected from the group consisting of Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, In, Zn, and Sn, a compound including a plurality of elements selected from the group consisting of these elements, a mixture including a plurality of elements selected from the group consisting of these elements, or one or more oxides selected from the group consisting of these elements. Effect of the Invention

[0022] The organic electroluminescent device according to an embodiment of the present invention can achieve high efficiency and long life.

[0023] The polycyclic compound according to an embodiment of the present invention can improve the lifetime and efficiency of an organic electroluminescent device. [Brief description of the drawings]

[0024] [Figure 1] 1 is a cross-sectional view illustrating an organic electroluminescent device according to an embodiment of the present invention. [Diagram 2] 1 is a cross-sectional view illustrating an organic electroluminescent device according to an embodiment of the present invention. [Diagram 3] 1 is a cross-sectional view illustrating an organic electroluminescent device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Since the present invention can be modified in various ways and can have various forms, specific embodiments are illustrated in the drawings and described in detail in the text, but it is not intended to limit the present invention to the specific embodiments, and it should be understood that the present invention includes all modifications, equivalents, and alternatives within the spirit and technical scope of the present invention.

[0026] In the drawings, like reference numerals are used for like components. In the accompanying drawings, the dimensions of the structures are exaggerated for clarity of the present invention. Terms such as first and second are used to describe various components, but the components are not limited to the terms. The terms are used only for the purpose of distinguishing one structural element from another component. For example, the first component may be named the second component, and similarly, the second component may be named the first component, without departing from the scope of the present invention. A singular expression includes a plural expression unless the context clearly indicates otherwise.

[0027] In this application, the terms "comprise" or "have" and the like are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described above in the specification, but are not intended to preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. In addition, when a layer, film, region, plate, or other part is described as being "on" another part, this includes not only the case where it is "directly on" the other part, but also the case where there is another part between them.

[0028] In this specification, [ka] means the position to be bound.

[0029] In this specification, "substituted or unsubstituted" means that the group is substituted or unsubstituted with one or more substituents selected from the group consisting of a deuterium atom, a halogen atom, a cyano group, a nitro group, an amino group, a silyl group, a thiol group, a hydroxyl group, a boron group, a phosphine oxide group, a phosphine sulfide group, an alkyl group, an alkenyl group, an aryl group, and a heterocyclic group. These substituents may be further substituted or unsubstituted with these substituents. Each of the exemplified substituents may be substituted or unsubstituted. For example, a biphenylyl group may be interpreted as an aryl group, or as a phenyl group substituted with a phenyl group.

[0030] In this specification, "bonding with adjacent groups to form a ring" means bonding with adjacent groups to each other to form a substituted or unsubstituted hydrocarbon ring, or a substituted or unsubstituted hetero ring. The hydrocarbon ring includes an aliphatic hydrocarbon ring and an aromatic hydrocarbon ring. The hetero ring includes an aliphatic hetero ring and an aromatic hetero ring. The hydrocarbon ring and the hetero ring are monocyclic or polycyclic. In addition, the ring formed by bonding with adjacent groups may be bonded to another ring to form a spiro structure. In addition, the ring may be bonded to adjacent groups via a single bond or a heteroatom such as a C (carbon) atom or an O (oxygen), S (sulfur), or N (nitrogen) atom to form a ring.

[0031] In this specification, the term "adjacent groups" refers to a substituent substituted on an atom directly bonded to the atom on which the substituent is substituted, another substituent substituted on an atom on which the substituent is substituted, or a substituent that is structurally most adjacent to the substituent. For example, two methyl groups in 1,2-dimethylbenzene are interpreted as "adjacent groups" to each other, and two ethyl groups in 1,1-diethylcyclopentene are interpreted as "adjacent groups" to each other.

[0032] In this specification, examples of halogen atoms include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

[0033] In this specification, an alkyl group is linear, branched, or cyclic. The number of carbon atoms in an alkyl group is 1 to 50, 1 to 30, 1 to 20, 1 to 10, or 1 to 6. Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, s-butyl, t-butyl, i-butyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, i-pentyl, neopentyl, t-pentyl, cyclopentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl ...3,3-dimethylbutyl, n-pentyl, i-pentyl, neopentyl, t-pentyl, cyclopentyl, 3,3-dimethylbutyl, n-pentyl, i-pentyl, i-pentyl, i-pentyl, i-pentyl, i-pentyl, i-pentyl, i-pentyl, i-pentyl, i-pentyl, i-pentyl, i-pentyl, i-pentyl, Hexyl, 2-butylhexyl, cyclohexyl, 4-methylcyclohexyl, 4-t-butylcyclohexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, t-octyl, 2-ethyloctyl, 2-butyloctyl, 2-hexyloctyl, 3,7-dimethyloctyl, cyclooctyl, n-nonyl, n-decyl, adamantyl n-ethyl group, 2-ethyldecyl group, 2-butyldecyl group, 2-hexyldecyl group, 2-octyldecyl group, n-undecyl group, n-dodecyl group, 2-ethyldodecyl group, 2-butyldodecyl group, 2-hexyldodecyl group, 2-octyldecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, 2-ethylhexadecyl group, 2-butylhexadecyl group, 2-hexylhexadecyl group, 2-octylhexadecyl group, Examples of the alkyl group include, but are not limited to, n-heptadecyl, n-octadecyl, n-nonadecyl, n-icosyl, 2-ethylicosyl, 2-butylicosyl, 2-hexylicosyl, 2-octylicosyl, n-henicosyl, n-docosyl, n-tricosyl, n-tetracosyl, n-pentacosyl, n-hexacosyl, n-heptacosyl, n-octacosyl, n-nonacosyl, and n-triacontyl groups.

[0034] In this specification, aryl group means any functional group or substituent derived from an aromatic hydrocarbon ring. The aryl group is a monocyclic aryl group or a polycyclic aryl group. The number of ring carbon atoms of the aryl group is 6 to 30, 6 to 20, or 6 to 15. Examples of aryl groups include, but are not limited to, phenyl, naphthyl, fluorenyl, anthracenyl, phenanthryl, biphenylyl, terphenylyl, quaterphenylyl, quinquephenylyl, sexiphenylyl, triphenylenyl, pyrenyl, benzofluoranthenyl, and chrysenyl.

[0035] In the present specification, the fluorenyl group may be substituted, and two substituents may be bonded to each other to form a spiro structure. Examples of fluorenyl groups that may be substituted are as follows. However, they are not limited thereto. [ka]

[0036] In this specification, the heteroaryl group is a heteroaryl group containing one or more of O, N, P, Si, and S as a heteroatom. The number of ring carbon atoms of the heteroaryl group is 2 to 30, or 2 to 20. The heteroaryl group is a monocyclic heteroaryl group or a polycyclic heteroaryl group. The polycyclic heteroaryl group may have, for example, a two-ring or three-ring structure. Examples of the heteroaryl group include a thiophenyl group, a furanyl group, a pyrrolyl group, an imidazolyl group, a thiazolyl group, an oxazolyl group, an oxadiazolyl group, a triazolyl group, a pyridyl group, a bipyridyl group, a pyrimidyl group, a triazinyl group, an acridyl group, a pyridazinyl group, a pyridinyl group, a quinolinyl group, a quinazolinyl group, a quinoxalinyl group, a phenoxazinyl group, a phthalazinyl group, a pyridopyrimidinyl group, a pyridopyrazinyl group, a pyrazinopyrazinyl group, an isoquinolinyl group, an indolyl group, a carbazolyl group, an N-aryl group, Examples of the alkyl group include, but are not limited to, an alkylcarbazolyl group, an N-heteroarylcarbazolyl group, an N-alkylcarbazolyl group, a benzoxazolyl group, a benzimidazolyl group, a benzothiazolyl group, a benzocarbazolyl group, a benzothiophenyl group, a dibenzothiophenyl group, a thienothiophenyl group, a benzofuranyl group, a phenanthrolinyl group, a thiazolyl group, an isoxazolyl group, a thiadiazolyl group, a phenothiazinyl group, a dibenzosilolyl group, a dibenzofuranyl group, a phenolyl group, and an azaborinyl group.

[0037] In this specification, the silyl group includes an alkylsilyl group and an arylsilyl group. Examples of the silyl group include, but are not limited to, a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, a vinyldimethylsilyl group, a propyldimethylsilyl group, a triphenylsilyl group, a diphenylsilyl group, a phenylsilyl group, and the like.

[0038] In this specification, the number of carbon atoms of the amino group is not particularly limited, but is from 1 to 30. The amino group includes an alkylamino group and an arylamino group. Examples of the amino group include, but are not limited to, a methylamino group, a dimethylamino group, a phenylamino group, a naphthylamino group, a 9-methyl-anthracenylamino group, and a diphenylamino group.

[0039] In this specification, the above description of the aryl group applies to the arylene group, except that the arylene group is a divalent group.

[0040] In this specification, the above description of the heteroaryl group applies to the heteroarylene group, except that the heteroarylene group is a divalent group.

[0041] Hereinafter, an organic electroluminescent device according to an embodiment of the present invention will be described with reference to FIGS.

[0042] 1 and 3, an organic electroluminescent device 10 according to an embodiment of the present invention includes a first electrode EL1, a hole transport region HTR, an emission layer EML, an electron transport region ETR, and a second electrode EL2, which are sequentially stacked.

[0043] The first electrode EL1 and the second electrode EL2 are disposed opposite to each other, and a plurality of organic layers are disposed between the first electrode EL1 and the second electrode EL2. The plurality of organic layers include a hole transport region HTR, an emission layer EML, and an electron transport region ETR. In an embodiment of the organic electroluminescent device 10, the emission layer EML contains the polycyclic compound of the embodiment described above.

[0044] Meanwhile, Fig. 2 is a cross-sectional view of an organic electroluminescent device 10 according to an embodiment in which 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, in comparison with Fig. 1. Fig. 3 is a cross-sectional view of an organic electroluminescent device 10 according to an embodiment in which 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, in comparison with Fig. 1.

[0045] 1 to 3, at least one of the organic layers may include a polycyclic compound according to an embodiment, which includes one electron donating group and one electron accepting group. In the polycyclic compound according to an embodiment, the electron donating group may include an azaborine moiety, and the accepting group may include any one of a cyano group, a carbonyl group, a boron group, a sulfonyl group, a sulfinyl group, a phosphine oxide group, a nitrogen-containing five-membered ring, and a nitrogen-containing six-membered monocyclic ring.

[0046] In the organic electroluminescent device 10 according to an embodiment, the first electrode EL1 is conductive. The first electrode EL1 is made of a metal alloy or a conductive compound. The first electrode EL1 is an anode.

[0047] The first electrode EL1 is a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. If the first electrode EL1 is a transmissive electrode, the first electrode EL1 is made of a transparent metal oxide, for example, ITO (indium tin oxide), IZO (indium zinc oxide), ZnO (zinc oxide), ITZO (indium tin zinc oxide), etc. If the first electrode EL1 is a semi-transmissive electrode or a reflective electrode, the first electrode EL1 includes Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, or a compound or mixture thereof (for example, a mixture of Ag and Mg). In addition, the first electrode EL1 may have a multi-layer structure including a reflective film or semi-transmissive film formed of the exemplified material, and a transparent conductive film made of ITO, IZO, ZnO, ITZO, etc. For example, the first electrode EL1 may include a multi-layer structure of ITO / Ag / ITO.

[0048] The hole transport region HTR is provided on the first electrode EL1, and includes at least one of a hole injection layer HIL, a hole transport layer HTL, a hole buffer layer, and an electron blocking layer EBL.

[0049] The hole transport region HTR may have a single layer of a single material, a single layer of a plurality of different materials, or a multi-layer structure having a plurality of layers of a plurality of different materials.

[0050] 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, or a single structure made of a hole injection material and a hole transport material. The hole transport region HTR may have a single layer structure made of a plurality of different materials, or a structure of a hole injection layer HIL / hole transport layer HTL, a hole injection layer HIL / hole transport layer HTL / hole buffer layer, a hole injection layer HIL / hole buffer layer, a hole transport layer HTL / hole buffer layer, or a hole injection layer HIL / hole transport layer HTL / electron blocking layer stacked in order from the first electrode EL1, but the present embodiment is not limited thereto.

[0051] The hole transport region HTR can be formed using various methods such as a vacuum deposition method, a spin coating method, a Langmuir-Blodgett (LB) method, an inkjet printing method, a laser printing method, a laser induced thermal imaging (LITI) method, and the like.

[0052] The hole injection layer HIL of the organic electroluminescent device 10 of one embodiment includes a known hole injection material. For example, the hole injection layer HIL may include triphenylamine-containing polyether ketone (TPAPEK), 4-isopropyl-4'-methyldiphenyliodonium tetrakis(pentafluorophenyl)borate (PPBI), N,N'-diphenyl-N,N'-bis-[4-(phenyl-m-tolyl-amino)-phenyl]-phenyl-4,4'-diamine (DNTPD), phthalocyanine compounds such as copper phthalocyanine, 4,4',4"-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA), N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (NPB), N,N'-bis(1-naphthyl)N,N'-diphenyl-4,4'-diamine (α-NPD), 4,4',4"-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA), N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (NPB), N,N'-bis(1-naphthyl)N,N'-diphenyl-4,4'-diamine (α-NPD), 4,4',4"-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA), N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (NPB), N,N'-bis(1-naphthyl)- ... The examples may include "-tris{N,N-diphenylamino}triphenylamine (TDATA), 4,4',4"-tris(N,N-2-naphthylphenylamino)triphenylamine (2-TNATA), polyaniline / dodecylbenzenesulfonic acid (PANI / DBSA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate) (PEDOT / PSS), polyaniline / camphorsulfonic acid (PANI / CSA), polyaniline / poly(4-styrenesulfonate) (PANI / PSS), or HAT-CN (dipyrazino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile). However, the present embodiment is not limited thereto.

[0053] The hole transport layer HTL of the organic electroluminescent device 10 of one embodiment includes a known hole transport material. For example, the hole transport layer HTL may include carbazole derivatives such as 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC), N-phenylcarbazole, polyvinylcarbazole, etc., N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine (TPD), 4,4',4"-tris(N-carbazolyl)triphenylamine (TCTA), N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (NPB), N,N'-bis(1-naphthyl)-N,N'-diphenyl-4,4'-diamine (α-NPD), etc. However, the present embodiment is not limited thereto.

[0054] On the other hand, the hole transport region HTR further includes an electron blocking layer EBL, which is disposed between the hole transport layer HTL and the light emitting layer EML. The electron blocking layer EBL serves to prevent the injection of electrons from the electron transport region ETR to the hole transport region HTR.

[0055] The electron blocking layer, EBL, comprises common materials known in the art. The electron blocking layer EBL may include, for example, a carbazole derivative such as N-phenylcarbazole or polyphenylcarbazole, a fluorene derivative, a triphenylamine derivative such as TPD (N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diamine) or TCTA (4,4',4"-tris(N-carbazolyl)triphenylamine), NPD (N,N'-di(naphthalen-1-yl)-N,N'-diphenyl-benzidine), TAPC (4,4'-cyclohexylidenebis[N,N-bis(4-methylphenyl)benzenamine]), HMTPD (4,4'-bis[N,N'-(3-tolyl)amino]-3,3'-dimethylbiphenyl), or mCP. As described above, the electron blocking layer EBL includes a polycyclic compound according to one embodiment of the present invention.

[0056] The thickness of the hole transport region HTR may be about 10 nm to about 1000 nm, for example, about 10 nm to about 500 nm. The thickness of the hole injection layer HIL may be, for example, about 3 nm to about 100 nm, and the thickness of the hole transport layer HTL may be about 3 nm to about 100 nm. For example, the thickness of the electron blocking layer EBL may be about 1 nm to about 100 nm. If the thicknesses of the hole transport region HTR, the hole injection layer HIL, the hole transport layer HTL, and the electron blocking layer EBL satisfy the above-mentioned ranges, a satisfactory level of hole transport properties can be obtained without a substantial increase in driving voltage.

[0057] In addition to the above-mentioned materials, the hole transport region HTR further includes a charge generating material to improve conductivity. The charge generating material is uniformly or non-uniformly dispersed in the hole transport region HTR. The charge generating material is, for example, a p-dopant. The p-dopant may be one of, but is not limited to, a quinone derivative, a metal oxide, and a cyano group-containing compound. For example, non-limiting examples of the p-dopant include, but are not limited to, quinone derivatives such as TCNQ (tetracyanoquinodimethane) and F4-TCNQ (2,3,5,6-tetrafluoro-tetracyanoquinodimethane), metal oxides such as tungsten oxide, and molybdenum oxide.

[0058] As described above, the hole transport region HTR includes at least one of a hole buffer layer and an electron blocking layer EBL in addition to the hole transport layer HTL and the hole injection layer HIL. The hole buffer layer compensates for the resonance distance according to the wavelength of light emitted from the emission layer EML to increase light emission efficiency. The material included in the hole buffer layer is a material that can be included in the hole transport region HTR.

[0059] The light-emitting layer EML is provided on the hole-transporting region HTR. The thickness of the light-emitting layer EML may be, for example, 10 nm to 60 nm. The light-emitting layer EML has a multilayer structure having a single layer of a single material, a single layer of multiple different materials, or multiple layers of multiple different materials.

[0060] The light-emitting layer EML emits one of red, green, blue, white, yellow, and cyan light. The light-emitting layer EML includes a fluorescent or phosphorescent light-emitting material.

[0061] In one embodiment, the emitting layer EML2 is a fluorescent emitting layer. For example, a part of the light emitted from the emitting layer EML may be due to thermally activated delayed fluorescence. In more detail, the emitting layer EML contains a light-emitting component that emits thermally activated delayed fluorescence, and in one embodiment, the emitting layer EML is a emitting layer that emits blue light and emits thermally activated delayed fluorescence.

[0062] In one embodiment, the light emitting layer EML includes a polycyclic compound represented by the following Chemical Formula 1. [ka]

[0063] In Chemical Formula 1, Ar 1 and Ar 2 are each independently a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms.

[0064] In Chemical Formula 1, R 1 ~R 8 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted amino group, a cyano group, a boron group, a carbonyl group, a silyl group, an oxy group, a phosphine oxide group, a phosphine sulfide group, a substituted or unsubstituted thiol group, a sulfonyl group, a substituted or unsubstituted alkyl group having from 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group having from 7 to 30 carbon atoms, a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms, or R 1 ~R 8 are bonded to each other to form a ring.

[0065] R 1 ~R 8The meaning of bonding to each other to form a ring is that adjacent R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 5 and R 6 , R 6 and R 7 , R 7 and R 8 Any pair of R 1 ~R 8 Ar 1 ~Ar 2 means that they are not bonded to each other to form a ring.

[0066] In Chemical Formula 1, R 1 ~R 8 At least two of these are represented by the following chemical formula 2. [ka]

[0067] In Chemical Formula 2, L is a single bond, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring carbon atoms, or is bonded to an adjacent group to form a ring. For example, L is an adjacent R 1 ~R 8 may be bonded to any one of the groups to form a ring.

[0068] In Chemical Formula 2, Ar 3 and Ar 4 each independently represents a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms, or is bonded to an adjacent group to form a ring.

[0069] In one embodiment, the Ar 3represents a substituted aryl group having from 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms.

[0070] In one embodiment, the Ar 1 is represented by the following chemical formula 3. [ka]

[0071] In Chemical Formula 3, V 1 ~V 5 are each independently N or CR 9 and R 9 is a hydrogen atom, a deuterium atom, a halogen atom, a boron group, a substituted or unsubstituted amino group, a cyano group, a carbonyl group, an oxy group, a silyl group, a thiol group, a phosphine oxide group, a phosphine sulfide group, a substituted or unsubstituted alkyl group having from 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having from 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having from 7 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms, or is bonded to an adjacent group to form a ring.

[0072] In one embodiment, V of Formula 3 1 ~V 5 At least one of them is CR 10 and R 10 is a substituted or unsubstituted alkyl group having 2 to 20 carbon atoms.

[0073] In one embodiment, R of Formula 1 1 ~R 4 At least one of the formulas is represented by formula 2, 5 ~R 8 At least one of the above is represented by Chemical Formula 2.

[0074] In one embodiment, R of Formula 1 1 ~R 8Two of these are represented by formula 2. For example, R 2 ~R 7 may be independently represented by Chemical Formula 2. In this case, Chemical Formula 1 is represented by Chemical Formula 4 below. [ka] In Chemical Formula 4, L' is a single bond, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring carbon atoms.

[0075] In formula 4, Ar 3 ' and Ar 4 Each ' is independently a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms, or is bonded to an adjacent group to form a ring.

[0076] In formula 4, Ar 1 ~Ar 4 , R 1 , R 3 ~R 6 , R 8 and L are as defined in Chemical Formula 1 and Chemical Formula 2.

[0077] In one embodiment, at least one of L and L′ in Chemical Formula 4 is a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring carbon atoms.

[0078] In one embodiment, L and L' in Formula 4 are each independently a single bond.

[0079] The polycyclic compound represented by Chemical Formula 1 in one embodiment is a delayed fluorescent material. The polycyclic compound in one embodiment is a thermally activated delayed fluorescent material.

[0080] The polycyclic compound of one embodiment represented by Chemical Formula 1 is represented by any one of the compounds shown in the first compound group below. [First compound group] [ka] [ka] [ka] [ka] [ka]

[0081] In the compounds described in the first compound group, iPr represents an isopropyl group, and SiPh 3 indicates a triphenylsilyl group, and NPh 2 represents a diphenylamino group.

[0082] The polycyclic compound represented by Chemical Formula 1 is used in the organic electroluminescent device 10 of the embodiment to improve the efficiency and lifetime of the organic electroluminescent device. In particular, the polycyclic compound represented by Chemical Formula 1 is used in the emission layer EML of the organic electroluminescent device 10 of the embodiment to improve the luminous efficiency and lifetime of the organic electroluminescent device.

[0083] In one embodiment, the emission layer EML includes a host and a dopant, the host is a delayed fluorescent host, and the dopant is a delayed fluorescent dopant. Meanwhile, the polycyclic compound of one embodiment represented by Chemical Formula 1 is included as a dopant material of the emission layer EML. For example, the polycyclic compound of one embodiment represented by Chemical Formula 1 may be used as a TADF dopant.

[0084] On the other hand, in one embodiment, the emitting layer EML includes a known host material. For example, in one embodiment, the emitting layer EML includes Alq 3 (tris(8-hydroxyquinolino)aluminum), CBP (4,4'-bis(N-carbazolyl)-1,1'-biphenyl), PVK (poly(n-vinylcarbazole), ADN (9,10-di(naphthalen-2-yl)anthracene), TCTA (4,4',4"-tris(carbazol-9-yl)-triphenylamine), TPBi (1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene), TBADN (3-tert-butyl-9 ,10-Di(naphth-2-yl)anthracene), DSA (Distyrylarylene), CDBP (4,4'-Bis(9-carbazolyl)-2,2'-dimethyl-biphenyl), MADN (2-Methyl-9,10-bis(naphthalen-2-yl)anthracene), DPEPO (Bis[2-(diphenylphosphino)phenyl]ether oxide), CP1 (Hexaphenylcyclotriphosphazene), UGH2 (1,4-Bis(triphenylsilyl)benzene), DPSiO 3 (Hexaphenylcyclotrisiloxane), DPSiO 4 (octaphenylcyclotetrasiloxane), or PPF (2,8-bis(diphenylphosphoryl)dibenzofuran). However, the embodiment is not limited thereto, and may include a known delayed fluorescent host material in addition to the presented host material.

[0085] On the other hand, in the organic electroluminescent device 10 of one embodiment, the light emitting layer EML further contains a known dopant material. In one embodiment, the light-emitting layer MEL includes, as a dopant, a styryl derivative (e.g., 1,4-bis[2-(3-N-ethylcarbazolyl)vinyl]benzene (BCzVB), 4-(di-p-tolylamino)-4'-[(di-p-tolylamino)styryl]stilbene (DPAVB), N-(4-((E)-2-(6-((E)-4-(diphenylamino)styryl)naphthalen-2-yl)vinyl)phenyl)-N-phenylbenzenamine (N-BDAVBi), perylene and its derivatives (e.g., 2,5,8,11-tetra-t-butylperylene (TBP)), pyrene and its derivatives (e.g., 1,1-dipyrene, 1,4-dipyrenylbenzene, 1,4-bis(N,N-diphenylamino)pyrene, etc.).

[0086] 1 to 3, in one embodiment of the organic electroluminescent device 10, an electron transport region ETR is provided on the light emitting layer EML. The electron transport region ETR includes, but is not limited to, at least one of an electron blocking layer, an electron transport layer ETL, and an electron injection layer EIL.

[0087] The electron transport region ETR has a single layer made of a single material, a single layer made of a plurality of different materials, or a multilayer structure having a plurality of layers made of a plurality of different materials.

[0088] For example, the electron transport region ETR may have a single layer structure of an electron injection layer EIL or an electron transport layer ETL, or may have a single layer structure made of an electron injection material and an electron transport material. The electron transport region ETR may have a single layer structure made of a plurality of different materials, or may have a structure of an electron transport layer ETL / electron injection layer EIL or a hole blocking layer / electron transport layer ETL / electron injection layer EIL stacked in order from the first electrode EL1, but is not limited thereto. The thickness of the electron transport region ETR may be, for example, about 10 nm to about 150 nm.

[0089] The electron transport region ETR can be formed using various methods such as vacuum deposition, spin coating, casting, LB method, inkjet printing, laser printing, and laser thermal transfer.

[0090] When the electron transport region ETR includes an electron transport layer ETL, for example, the electron transport region ETR is 3 (Tris(8-hydroxyquinolinato)aluminum), 1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene, 2,4,6-tris(3'-pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine, 2-(4-(N-phenylbenzoimidazolyl-1-ylphenyl)-9,10-dinaphthylanthracene, TPBi(1,3,5-tri(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene), BCP(2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline), Bphe n(4,7-diphenyl-1,10-phenanthroline), TAZ(3-(4-biphenylyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole), NTAZ(4-(naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole), tBu-PBD(2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole), BAlq(bis(2-methyl-8-quinolinolato-N1,O8)-(1,1'-biphenyl-4-olato)aluminum), Bebq 2 (beryllium bis(benzoquinolin-10-olato), ADN (9,10-di(naphthalen-2-yl)anthracene), or mixtures thereof, but embodiments are not limited thereto.

[0091] When the electron transport region ETR includes the electron transport layer ETL, the thickness of the electron transport layer ETL may be about 10 nm to about 100 nm, for example, about 15 nm to about 50 nm. If the thickness of the electron transport layer HTL satisfies the above-mentioned range, a satisfactory level of electron transport properties can be obtained without a substantial increase in driving voltage.

[0092] When the electron transport region ETR includes the electron injection layer EIL, the electron transport region ETR may be made of, for example, a lanthanum group metal such as LiF, LiQ (lithium quinolate), Li2O, BaO, NaCl, CsF, or Yb, or a metal halide such as RbCl, RbI, or KI, but the embodiment is not limited thereto. The electron injection layer EIL may also be made of a material in which an electron transport material and an insulating organo metal salt are mixed. The organo metal salt is a material having an energy band gap of about 4 eV or more. In more detail, for example, the organo metal salt includes a metal acetate, a metal benzoate, a metal acetoacetate, a metal acetylacetonate, or a metal stearate.

[0093] When the electron transport region ETR includes an electron injection layer EIL, the thickness of the electron injection layer EIL may be about 0.1 nm to about 10 nm, or about 0.3 nm to about 9 nm. If the thickness of the electron injection layer EIL satisfies the above-mentioned range, a satisfactory level of electron injection characteristics can be obtained without a substantial increase in driving voltage.

[0094] The electron transport region ETR includes a hole blocking layer as described above. The hole blocking layer may include, for example, but is not limited to, at least one of BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) and Bphen (4,7-diphenyl-1,10-phenanthroline).

[0095] The second electrode EL2 is provided on the electron transport region ETR. The second electrode EL2 has electrical conductivity. The second electrode EL2 is made of a metal alloy or a conductive compound. The second electrode layer EL2 is a cathode. The second electrode EL2 is a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. If the second electrode EL2 is a transmissive electrode, the second electrode EL2 is made of a transparent metal oxide, such as ITO, IZO, ZnO, ITZO, etc.

[0096] If the second electrode EL2 is a semi-transmissive electrode or a reflective electrode, the second electrode EL2 contains Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, or a compound or mixture thereof (e.g., a mixture of Ag and Mg). It may also have a multi-layer structure including a reflective film or semi-transmissive film made of the exemplified materials, and a transparent conductive film made of ITO, IZO, ZnO, ITZO, or the like.

[0097] Although not shown, the second electrode EL2 is connected to an auxiliary electrode, If the second electrode EL2 is connected to the auxiliary electrode, the resistance of the second electrode EL2 can be reduced.

[0098] In the organic electroluminescent device 10, when a voltage is applied to the first electrode EL1 and the second electrode EL2, holes injected from the first electrode EL1 move to the emission layer EML via the hole transport region HTR, and electrons injected from the second electrode EL2 move to the emission layer EML via the electron transport region ETR. The electrons and holes recombine in the emission layer EML to generate excitons, and the excitons emit light as they fall from the excited state to the bottom state.

[0099] If the organic electroluminescent device 10 is a front emission type, the first electrode EL1 is a reflective electrode, and the second electrode EL2 is a transmissive electrode or a semi-transmissive electrode. If the organic electroluminescent device 10 is a back emission type, the first electrode EL1 is a transmissive electrode or a semi-transmissive electrode, and the second electrode EL2 is a reflective electrode.

[0100] The organic electroluminescent device 10 according to one embodiment of the present invention exhibits improved luminous efficiency and life characteristics by using the above-mentioned polycyclic compound as a light-emitting layer material.

[0101] One embodiment of the present invention provides a polycyclic compound represented by the following Chemical Formula 1: [ka]

[0102] In Chemical Formula 1, Ar1 and Ar 2 are each independently a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms.

[0103] In Chemical Formula 1, R 1 ~R 8 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted amino group, a cyano group, a boron group, a carbonyl group, a silyl group, an oxy group, a phosphine oxide group, a phosphine sulfide group, a substituted or unsubstituted thiol group, a sulfonyl group, a substituted or unsubstituted alkyl group having from 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group having from 7 to 30 carbon atoms, a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms, or R 1 ~R 8 are bonded to each other to form a ring.

[0104] R 1 ~R 8 The meaning of bonding to each other to form a ring is that adjacent R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 5 and R 6 , R 6 and R 7 , R 7 and R 8 Any pair of R 1 ~R 8 Ar 1 ~Ar 2 means that they are not bonded to each other to form a ring.

[0105] In Chemical Formula 1, R 1 ~R 8 At least two of these are represented by the following chemical formula 2. [ka]

[0106] In Chemical Formula 2, L is a single bond, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring carbon atoms, or is bonded to an adjacent group to form a ring. For example, L is an adjacent R 1 ~R 8 It bonds to one of the following to form a ring.

[0107] In Chemical Formula 2, Ar 3 and Ar 4 each independently represents a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms, or is bonded to an adjacent group to form a ring.

[0108] The polycyclic compound represented by Chemical Formula 1 according to an embodiment can be similarly described in relation to the polycyclic compound in the organic electroluminescent device according to the above embodiment.

[0109] The polycyclic compound in one embodiment is any one selected from the compounds shown in the first compound group described above. EXAMPLES

[0110] The present invention will be described in more detail with reference to the following specific examples and comparative examples. The following examples are merely illustrative to aid in understanding the present invention, and the scope of the present invention is not limited thereto.

[0111] 1. Synthesis of polycyclic compounds The synthesis method of the polycyclic compound described below is merely an example, and the synthesis method of the polycyclic compound according to the embodiment of the present invention is not limited to the following example.

[0112] (Synthesis of Compound 2) [ka]

[0113] 1) Synthesis of intermediate B Under an Ar atmosphere, intermediate A (15 g, 31 mmol) was added to iodinated benzene (32 g, 157 mmol) in a 200 mL three-neck flask. CuI (6.0 g, 31 mmol) and potassium carbonate (8.6 g, 62 mmol) were added thereto, and the mixture was stirred at 190°C for 80 hours. After the reaction, toluene was added and the mixture was filtered, and the resulting organic phase was concentrated to obtain a viscous substance. The resulting crude product was purified by column chromatography (silica gel), and 10.3 g (18 mmol, 58% yield) of intermediate B was obtained. The mass number of intermediate B measured by FAB-MS measurement was 557.

[0114] 2) Synthesis of intermediate C In a 500mL three-neck flask under Ar atmosphere, 150mL of dehydrated diethyl ether was added to intermediate B (6.2g, 12.8mmol) to dissolve it, and the mixture was stirred at -78℃ for 1 hour. 16mL (25mmol) of 1.6M n-BuLi hexane solution was added dropwise thereto, and the mixture was stirred for 2 hours. 4.0g (14mmol) of 2,4,6-triisopropylphenylboronic acid methyl ester was added thereto, and the temperature of the reaction solution was raised to room temperature while stirring, and the mixture was stirred at room temperature overnight. After the reaction, the reaction was stopped by adding water, and the product was extracted with chloroform. The obtained organic phase was concentrated to obtain a crude product as a solid. The obtained crude product was purified by column chromatography (silica gel), and 2.8g (4.6mmol, 36% yield) of intermediate C was obtained. The mass number of intermediate C measured by FAB-MS measurement was 613.

[0115] 3) Synthesis of compound 2 [ka]

[0116] Under an Ar atmosphere, a 100 mL three-neck flask was charged with intermediate C (1.1 g, 1.8 mmol), 4,4'-ditolylamine (0.788 g, 4.0 mmol), and Pd 2 (dba) 3(0.183g, 0.20mmol), (t-Bu) 3 P (0.162 g, 0.80 mmol) and sodium t-butoxide (0.769 g, 8.0 mmol) were added, and the mixture was stirred in 20 mL of toluene solvent at 80° C. for 12 hours. After cooling in air, water was added to separate the organic layer, and the solvent was removed. The resulting crude product was purified by silica gel chromatography to obtain 1.1 g (1.3 mmol, 72% yield) of compound 2 as a white solid. The mass number of compound 2 measured by FAB-MS measurement was 848.

[0117] (Synthesis of compound 10) [ka]

[0118] Under an Ar atmosphere, a 100 mL three-neck flask was charged with intermediate C (1.1 g, 1.8 mmol), N-phenyl-3-dibenzofuranamine (0.466 g, 4.0 mmol), and Pd 2 (dba) 3 (0.183g, 0.20mmol), (t-Bu) 3 P (0.162 g, 0.80 mmol) and sodium t-butoxide (0.769 g, 8.0 mmol) were added, and the mixture was stirred in 20 mL of toluene solvent at 80° C. for 12 hours. After cooling in air, water was added to separate the organic layer, and the solvent was removed. The resulting crude product was purified by silica gel chromatography to obtain 1.5 g (1.5 mmol, 83% yield) of compound 10 as a white solid. The mass number of compound 10 measured by FAB-MS measurement was 971.

[0119] (Synthesis of compound 19) [ka]

[0120] Under an Ar atmosphere, a 100 mL three-neck flask was charged with intermediate C (1.1 g, 1.8 mmol), N-phenyl-3-N-phenyl-4-biphenylamine (0.980 g, 4.0 mmol), and Pd 2 (dba)3 (0.183g, 0.20mmol), (t-Bu) 3 P (0.162 g, 0.80 mmol) and sodium t-butoxide (0.769 g, 8.0 mmol) were added, and the mixture was stirred in 20 mL of toluene solvent at 80° C. for 12 hours. After cooling in air, water was added to separate the organic layer, and the solvent was removed. The resulting crude product was purified by silica gel chromatography to obtain 1.2 g (1.3 mmol, 72% yield) of compound 19 as a white solid. The mass number of compound 19 measured by FAB-MS measurement was 944.

[0121] (Synthesis of compound 38) 1) Synthesis of intermediate D [ka]

[0122] In a 200 mL round bottom flask, add 27.3 g (80.0 mmol) of 2,6-dibromodibenzothiophene, 2.06 g (40.1 mmol) of oxo, 3.13 g (17.8 mmol) of oxo acid, 80 mL of acetic acid, 5 mL of sulfuric acid, 5 mL of water, and 2 mL of CHCl. 3 The mixture was stirred at 65° C. for 3 hours. After cooling, water was added to the mixture, and the precipitated solid was suction filtered and washed with water three times. The residue was recrystallized from toluene to obtain 27.0 g (57.7 mmol, 72% yield) of intermediate D. The mass number of intermediate D measured by FAB-MS was 468.

[0123] 2) Synthesis of intermediate E [ka]

[0124] In a 500 mL three-neck flask under an Ar atmosphere, 27.0 g (57.7 mmol) of intermediate D, 14.5 g (57.7 mmol) of 2,5-dibromoaniline, and Pd(OAc) 20.65g (2.9mmol), Xantphos 1.67g (2.9mmol), and NaOtBu 5.82g (60.0mmol) were added and stirred in 120mL dioxane solvent at 100°C for 8 hours. After cooling in air, water was added to separate the organic layer and the solvent was removed. The obtained crude product was purified by column chromatography (silica gel), and 23.5g (yield 69%) of intermediate E was obtained. The mass number of intermediate E measured by FAB-MS measurement was 591.

[0125] 3) Synthesis of intermediate F [ka]

[0126] Under an Ar atmosphere, intermediate E (23.5 g, 40 mmol) was added to iodinated benzene (40.8 g, 200 mmol) in a 200 mL three-neck flask. CuI (7.6 g, 40 mmol) and potassium carbonate (11.1 g, 80 mmol) were added thereto, and the mixture was stirred at 190 ° C for 80 hours. After the reaction, toluene was added and filtered, and the obtained organic phase was concentrated to obtain a viscous substance. The obtained crude product was purified by column chromatography (silica gel), and 15.1 g (22.8 mmol, 57% yield) of intermediate F was obtained. The mass number of intermediate F measured by FAB-MS measurement was 667.

[0127] 4) Synthesis of intermediate G [ka]

[0128] In a 500 mL three-neck flask under an Ar atmosphere, 230 mL of dehydrated diethyl ether was added to intermediate F (15.1 g, 22.8 mmol) to dissolve it, and the mixture was stirred at -78 ° C for 1 hour. 29 mL (46 mmol) of 1.6 M n-BuLi hexane solution was added dropwise thereto, and the mixture was stirred for 2 hours. 6.4 g (23 mmol) of 2,4,6-triisopropylphenylboronic acid methyl ester was added thereto, and the temperature of the reaction solution was raised to room temperature while stirring, and the mixture was stirred at room temperature overnight. After the reaction, the reaction was stopped by adding water, and the product was extracted with chloroform. The obtained organic phase was concentrated to obtain a crude product as a solid. The obtained crude product was purified by column chromatography (silica gel), and 4.76 g (6.6 mmol, 29% yield) of intermediate G was obtained. The mass number of intermediate G measured by FAB-MS measurement was 721.

[0129] 5) Synthesis of compound 38 [ka]

[0130] Under an Ar atmosphere, a 100 mL three-neck flask was charged with intermediate G (4.76 g, 6.6 mmol), diphenylamine (2.46 g, 14.5 mmol), and Pd 2 (dba) 3 (0.12g, 0.13mmol), (t-Bu) 3 P (0.21 g, 1.06 mmol) and sodium t-butoxide (1.39 g, 14.5 mmol) were added, and the mixture was stirred in 30 mL of toluene solvent at 100° C. for 12 hours. After cooling in air, water was added, the organic layer was separated, and the solvent was removed. The resulting crude product was purified by silica gel chromatography to obtain 3.68 g (4.1 mmol, 63% yield) of compound 38 as a yellow solid. The mass number of compound 38 measured by FAB-MS measurement was 898.

[0131] 2. Fabrication and evaluation of organic electroluminescent devices containing polycyclic compounds (Fabrication of organic electroluminescent devices) [Example Compounds] [ka] [Comparative Example Compound] [ka]

[0132] The organic electroluminescent devices of the examples and comparative examples were produced in the following manner.

[0133] After patterning ITO to a thickness of 150 nm on a glass substrate, it was washed with ultrapure water and subjected to UV ozone treatment for 10 minutes. Next, HAT-CN was evaporated to a thickness of 10 nm, α-NPD was evaporated to a thickness of 80 nm, and mCP was evaporated to a thickness of 5 nm to form a hole transport region.

[0134] Next, when forming the light-emitting layer, the polycyclic compound of one example or the comparative compound and DPEPO were co-deposited in a ratio of 20:80 to form a layer with a thickness of 20 nm. Next, a layer with a thickness of 10 nm was formed using DPEPO. That is, in the light-emitting layer formed by co-deposition, in Examples 1 to 4, compounds 2, 10, 19, and 38 were mixed with DPEPO and deposited, respectively, and in Comparative Examples 1 to 3, comparative compounds C-1, C-2, and C-3 were mixed with DPEPO and deposited.

[0135] A 30 nm thick layer of TPBi was formed on the light-emitting layer, followed by a 0.5 nm thick layer of LiF to form the electron transport region, and then a 100 nm thick second electrode was formed of aluminum (Al).

[0136] In the examples, the hole transport region, the light emitting layer, the electron transport region, and the second electrode were formed using a vacuum deposition apparatus.

[0137] (Evaluation of the characteristics of organic electroluminescent devices) In order to evaluate the characteristics of the organic electroluminescent devices according to the examples and comparative examples, the half-width (nm), external quantum yield (%), and lifetime were measured. The measurements were performed using a Hamamatsu Photonics C9920-11 brightness distribution characteristic measuring device. The lifetime was measured at an initial brightness of 100 cd / m2 The half-life of the luminance from 1000 to 10 ... 2 The values ​​at are shown. [Table 1]

[0138] Referring to Table 1, it can be seen that the organic electroluminescent devices of Examples 1 to 4, in which the polycyclic compound of one embodiment is used as a dopant material in the light-emitting layer, exhibit higher efficiency, narrower half-width, and outstanding lifetime than those of Comparative Examples 1 to 3.

[0139] It is considered that in Examples 1 to 4, the molecules are stabilized by including two amine groups in the azaborine moiety, and thus higher efficiency, narrower half-width, and outstanding life span are achieved compared to the comparative examples.

[0140] Compounds C-1, C-2, and C-3 of Comparative Examples 1 to 3 have one diphenylamino group substituted at the azaborine core portion, and are considered to have lower stability than the compounds of the Examples.

[0141] In addition, compound C-1 of Comparative Example 1 does not contain a substituent at the diphenylamino group, so the amino group is not further stabilized, and a phenyl group having a phenyl group as a substituent is bonded to a boron atom, so the boron group is unstable compared to the example compound having an isopropyl group as a substituent, and structural changes cannot be suppressed, and therefore it is considered that the life and efficiency of the element are reduced.

[0142] Compound C-2 of Comparative Example 2 does not have a substituent that acts as a sterically protective group around the boron atom, and is therefore unstable compared to the compounds of the Examples, and therefore the lifespan of the device is particularly reduced. In addition, the boron group of the azaborine group additionally forms a condensed ring, and the boron group is particularly unstable, which results in a decrease in molecular stability and a decrease in device lifespan.

[0143] In compound C-3 of Comparative Example 3, an acridine group is bonded to a fluorenyl group, and the bond between the azaborine group and the acridine group is significantly twisted, which is believed to result in reduced stability and a shorter lifespan than in the Examples.

[0144] The organic electroluminescent device of one embodiment can achieve high luminous efficiency in the blue light wavelength region by using the polycyclic compound represented by Chemical Formula 1 as the material of the light emitting layer.

[0145] Although the present invention has been described above with reference to preferred embodiments thereof, it will be understood by those skilled in the art or those having ordinary knowledge in the art that various modifications and variations of the present invention may be made without departing from the spirit and technical scope of the present invention as set forth in the claims below.

[0146] Therefore, the technical scope of the present invention should be determined not by the contents described in the detailed description of the specification, but by the claims. [Explanation of symbols]

[0147] 10: Organic electroluminescent element EL1: First electrode EL2: second electrode HTR: hole transport region EML: Light-emitting layer ETR: Electron transport region

Claims

1. A first electrode; a hole transport region disposed over the first electrode; a light-emitting layer disposed over the hole transport region; an electron transport region disposed over the light emitting layer; a second electrode disposed over the electron transport region; The first electrode and the second electrode each independently include any one selected from the group consisting of Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, In, Zn, and Sn, a compound including a plurality of elements selected from among these elements, a mixture including a plurality of elements selected from among these elements, or one or more oxides selected from among these elements; The light-emitting layer is an organic electroluminescent device including a polycyclic compound represented by the following Chemical Formula 1: 【Chemistry 1】 In Chemical Formula 1, The Ar １ is represented by the following chemical formula 3: 【Chemistry 3】 In the above Chemical Formula 3, V2 and V4 are CR ９ and V 1 , V 3 and V 5 are CR 10 ; R ９ is a hydrogen atom or a deuterium atom, R １０ is an unsubstituted isopropyl group, Ar ２ is an unsubstituted phenyl group, R １ ~R ８ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted amino group, a cyano group, a boron group, a carbonyl group, a silyl group, an oxy group, a phosphine oxide group, a phosphine sulfide group, a substituted or unsubstituted thiol group, a sulfonyl group, a substituted or unsubstituted alkyl group having from 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group having from 7 to 30 carbon atoms, a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms, or R １ ~R ８ are bonded together to form a ring, R １ ~R ８ At least two of the above are represented by the following formula 2: 【Chemistry 2】 In the above Chemical Formula 2, L is a single bond or an unsubstituted phenylene group; Ar ３ and Ar ４ each independently represents a substituted or unsubstituted phenyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group, and does not bond to an adjacent group to form a ring.

2. The organic electroluminescent device according to claim 1 , wherein the compound represented by Chemical Formula 1 is a thermally activated delayed fluorescent material.

3. The Ar ３ 2. The organic electroluminescent device according to claim 1, wherein is an unsubstituted phenyl group, an unsubstituted naphthyl group, an unsubstituted dibenzofuranyl group, or an unsubstituted dibenzothiophenyl group.

4. The R １ ~R ４ At least one of the formulas is represented by formula 2, The R ５ ~R ８ 2. The organic electroluminescent device according to claim 1, wherein at least one of the organic electroluminescent devices is represented by the formula 2. Optical element.

5. The organic electroluminescent device according to claim 1 , wherein the compound represented by Formula 1 is represented by the following Formula 4: 【Chemistry 4】 In the above Chemical Formula 4, L' is a single bond or an unsubstituted phenylene group; Ar ３ ' and Ar ４ each ' is independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group, which does not form a ring with an adjacent group; Ar １ ~Ar ４ , R １ , R ３ ~R ６ , R ８ and L are as defined in Formula 1 and Formula 2.

6. The organic electroluminescent device according to claim 1 , wherein the compound represented by Chemical Formula 1 is any one of the compounds represented by the following first compound group: [First compound group] 【Chemistry 5】 【Chemistry 6】 【Chemistry 7】 【Chemistry 8】 【Chemistry 9】 。

7. The light-emitting layer is a delayed fluorescent light-emitting layer containing a host and a dopant, The organic electroluminescent device according to claim 1 , wherein the dopant is a polycyclic compound.

8. A polycyclic compound represented by the following chemical formula 1: 【Chemistry 10】 In Chemical Formula 1, The Ar １ is represented by the following chemical formula 3: 【Chemistry 3】 In the above Chemical Formula 3, V2 and V4 are CR ９ and V 1 , V 3 and V 5 are CR 10 ; R ９ is a hydrogen atom or a deuterium atom, The R １０ is an unsubstituted isopropyl group, Ar ２ is an unsubstituted phenyl group, R １ ~R ８ are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted amino group, a cyano group, a boron group, a carbonyl group, a silyl group, an oxy group, a phosphine oxide group, a phosphine sulfide group, a substituted or unsubstituted thiol group, a sulfonyl group, a substituted or unsubstituted alkyl group having from 1 to 20 carbon atoms, a substituted or unsubstituted aralkyl group having from 7 to 30 carbon atoms, a substituted or unsubstituted aryl group having from 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring carbon atoms, or R １ ~R ８ are bonded together to form a ring, R １ ~R ８ At least two of the above are represented by the following formula 2: 【Chemistry 11】 In the above Chemical Formula 2, L is a single bond or an unsubstituted phenylene group; Ar ３ and Ar ４ each independently represents a substituted or unsubstituted phenyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group, and does not bond to an adjacent group to form a ring.

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