Organic electroluminescent compound and organic electroluminescent device comprising the same

Abstract

The present disclosure relates to an organic electroluminescent compound and an organic electroluminescent device comprising the same. An organic electroluminescent device having improved driving voltage and / or current efficiency characteristics can be provided by comprising the organic electroluminescent compound according to the present disclosure.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to an organic electroluminescent compound and an organic electroluminescent device including the same. BACKGROUND

[0002] An electroluminescent (EL) device is a self-light-emitting device, which has advantages in that it provides a wider viewing angle, a greater contrast ratio, and a faster response time. An organic EL device was first developed by Eastman Kodak in 1987 by using small aromatic diamine molecules and aluminum complexes as a material for forming a light-emitting layer [Appl. Phys. Lett. 51, 913, 1987].

[0003] An organic electroluminescent device (OLED) converts electrical energy into light by applying electrical power to an organic light-emitting material, and generally includes an anode, a cathode, and an organic layer formed between the two electrodes. The organic layer of the OLED can include a hole injection layer, a hole transport layer, a hole auxiliary layer, a light-emitting auxiliary layer, an electron blocking layer, a light-emitting layer (containing a host and a dopant material), an electron buffer layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc. The materials used in the organic layer can be classified into a hole injection material, a hole transport material, a hole auxiliary material, a light-emitting auxiliary material, an electron blocking material, a light-emitting material, an electron buffer material, a hole blocking material, an electron transport material, an electron injection material, etc. In the OLED, due to the application of a voltage, holes are injected from the anode into the light-emitting layer, electrons are injected from the cathode into the light-emitting layer, and high-energy excitons are formed by recombination of the holes and the electrons. By this energy, an organic light-emitting compound reaches an excited state, and light emission occurs by emitting light from the energy due to the recovery of the excited state of the organic light-emitting compound to the ground state.

[0004] Recently, according to a larger area of a display, there is a need for a light-emitting material that can exhibit more beautiful and vivid colors. Specifically, in the case of a material emitting blue light, materials such as ADN and DPVBi are used as a host material, and materials such as an aromatic amine-based compound, a copper phthalocyanine compound, a carbazole-based derivative, a perylene-based derivative, a coumarin-based derivative, and a pyrene-based derivative are used as a dopant material. However, these materials are difficult to obtain a deep blue color having high color purity, and are problematic in that they have poorer current efficiency as the wavelength becomes shorter.

[0005] Therefore, in terms of realizing a full-color display, there is a need to develop a light-emitting material for a deep blue color having excellent current efficiency and other organic materials having an energy level matching a material emitting blue light.

[0006] Korean Patent No. 1423070 discloses an organic electroluminescent compound comprising an anthracene moiety. However, this reference does not specifically disclose the organic electroluminescent compound of the present disclosure comprising an aromatic moiety in which a biphenyl and a naphthalene are fused. SUMMARY

[0007] TECHNICAL PROBLEM

[0008] An object of the present disclosure is to first provide an organic electroluminescent compound that effectively produces an organic electroluminescent device having a low driving voltage and / or a high current efficiency characteristic. Second is to provide an organic electroluminescent device comprising the same.

[0009] SOLUTION TO PROBLEM

[0010] Organic electroluminescent devices that emit blue light have hitherto generally used have lower current efficiency than organic electroluminescent devices that emit green and red light. This is because organic electroluminescent devices that emit blue light use a fluorescent dopant. The energy transfer mechanism of a fluorescent material follows energy transfer. In energy transfer, host luminescence is important in exciting a dopant. That is, as host luminescence increases, the current efficiency of an organic electroluminescent device increases. In order to increase host luminescence, quenching of host luminescence is generally required to be reduced, and it is considered that quenching of host luminescence is due to stacking of the host. The present inventors have introduced a bulky aromatic moiety in which a biphenyl and a naphthalene are fused as a substituent in order to hinder stacking of the host after investigation. As a result, it was confirmed that the current efficiency of a blue organic electroluminescent device was improved. Further, it is believed that because the aromatic moiety of the present disclosure in which a biphenyl and a naphthalene are fused comprises a naphthalene structure, which is excellent in luminescence, the current efficiency of an organic electroluminescent device that emits blue light can be more effectively increased. Specifically, the present inventors have accomplished the present invention by finding an organic electroluminescent compound represented by Formula 1 below.

[0011]

[0012] wherein

[0013] Ar1 represents a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (5- to 30-membered)heteroaryl;

[0014] R5 and R6 each independently represent hydrogen, deuterium, halogen, cyano, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (5- to 30-membered)heteroaryl;

[0015] Ar2 represents

[0016] wherein Ar2is connected to one of R1to R4at position (* indicates the position of connection to Ar2), and is not connected to R1to R4each independently represent hydrogen, deuterium, halogen, cyano, a substituted or unsubstituted (C1-C30)alkyl group, a substituted or unsubstituted (C6-C30)aryl group, or a substituted or unsubstituted (5- to 30-membered)heteroaryl group;

[0017] a and d each independently represent an integer of 1 to 3, and b, c, e and f each independently represent an integer of 1 to 4;

[0018] wherein if a to f are an integer of 2 or more, each R1to each R6may be the same as or different from each other.

[0019] Advantages of the present invention

[0020] By using the organic electroluminescent compound according to the present disclosure, an organic electroluminescent device having improved driving voltage and / or current efficiency characteristics can be produced. DETAILED DESCRIPTION

[0021] Hereinafter, the present disclosure will be described in detail. However, the following description is intended to explain the application, and is not meant in any way to restrict the scope of the application.

[0022] The term "organic electroluminescent compound" in the present disclosure means a compound that can be used in an organic electroluminescent device and, if necessary, can be contained in any layer constituting an organic electroluminescent device.

[0023] The term "organic electroluminescent material" in the present disclosure means a material that can be used in an organic electroluminescent device and can contain at least one compound. If necessary, the organic electroluminescent material can be contained in any layer constituting an organic electroluminescent device. For example, the organic electroluminescent material can be a hole injection material, a hole transport material, a hole auxiliary material, a light-emitting auxiliary material, an electron blocking material, a light-emitting material, an electron buffer material, a hole blocking material, an electron transport material, an electron injection material, etc.

[0024] The organic electroluminescent material of the present disclosure can contain at least one compound represented by Formula 1. The compound represented by Formula 1 can be contained in a light-emitting layer, but is not limited thereto. When contained in a light-emitting layer, the compound represented by Formula 1 can be contained as a host, e.g., a host for emitting blue light. According to one embodiment of the present disclosure, the compound having Formula 1 can be a fluorescent host, e.g., a fluorescent host for emitting blue light.

[0025] Hereinafter, the compound represented by Formula 1 will be described in more detail.

[0026] In the present document, the term "(C1-C30)alkyl" means a straight chain or branched alkyl group having 1 to 30 carbon atoms constituting the chain, wherein the number of carbon atoms is preferably 1 to 20, and more preferably 1 to 10. The above alkyl group can include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, and the like. The term "(C2-C30)alkenyl" means a straight chain or branched alkenyl group having 2 to 30 carbon atoms constituting the chain, wherein the number of carbon atoms is preferably 2 to 20, and more preferably 2 to 10. The above alkenyl group can include ethenyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 2-methylbut-2-enyl, and the like. The term "(C2-C30)alkynyl" means a straight chain or branched alkynyl group having 2 to 30 carbon atoms constituting the chain, wherein the number of carbon atoms is preferably 2 to 20, and more preferably 2 to 10. The above alkynyl group can include ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-methylpent-2-ynyl, and the like. The term "(C3-C30)cycloalkyl" means a monocyclic or polycyclic hydrocarbon having 3 to 30 ring skeleton carbon atoms, wherein the number of carbon atoms is preferably 3 to 20, and more preferably 3 to 7. The above cycloalkyl group can include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and the like. The term "(3- to 7-membered)heterocycloalkyl" means a cycloalkyl group having 3 to 7, preferably 5 to 7 ring skeleton atoms and containing at least one heteroatom selected from the group consisting of B, N, O, S, Si, and P, preferably from the group consisting of O, S, and N. The above heterocycloalkyl group can include tetrahydrofuran, pyrrolidine, thiolan, tetrahydropyran, and the like. The term "(C6-C30)aryl" means a monocyclic or fused ring group derived from an aromatic hydrocarbon having 6 to 30 ring skeleton carbon atoms, wherein the number of ring skeleton carbon atoms is preferably 6 to 25, more preferably 6 to 18. The above aryl group can be partially saturated, and can contain a spiro structure. The above aryl group can include phenyl, biphenyl, terphenyl, naphthyl, binaphthyl, phenylnaphthyl, naphthylphenyl, phenylterphenyl, fluorenyl, phenylfluorenyl, benzofluorenyl, dibenzofluorenyl, phenanthryl, phenylphenanthryl, anthryl, indenyl, triphenylenyl, pyrenyl, tetracenyl, perylenyl, naphthacenyl, fluoranthenyl, spirobifluorenyl, azulenyl, and the like. More specifically, the aryl group can include phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, benzanthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl, 9-phenanthryl, naphthacenyl, pyrenyl, 1- pyrenyl, 2- pyrenyl, 3- pyrenyl, 4- pyrenyl, 5- pyrenyl, 6- phenanthryl, benzo[c]phenanthryl, benzo[g] phenyl, 1 -triphenylyl, 2-triphenylyl, 3-triphenylyl, 4-triphenylyl, 1 -fluorenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl, 9-fluorenyl, benzofluorenyl, dibenzofluorenyl, 2-biphenylyl, 3-biphenylyl, 4-biphenylyl, o-terphenylyl, m-terphenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-quaterphenyl, 3-fluoranthenyl, 4-fluoranthenyl, 8-fluoranthenyl, 9-fluoranthenyl, benzofluoranthene, o-tolyl, m-tolyl, p-tolyl, 2,3-xylyl, 3,4-xylyl, 2,5-xylyl, mesityl, o-cumenyl, m-cumenyl, p-cumenyl, p-t-butylphenyl, p-(2-phenylpropyl)phenyl, 4'-methylbiphenylyl, 4"-t-butyl-p-terphenyl-4-yl, 9,9-dimethyl-1 -fluorenyl, 9,9-dimethyl-2-fluorenyl, 9,9-dimethyl-3-fluorenyl, 9,9-dimethyl-4-fluorenyl, 9,9-diphenyl-1 -fluorenyl, 9,9-diphenyl-2-fluorenyl, 9,9-diphenyl-3-fluorenyl, 9,9-diphenyl-4-fluorenyl, and the like.

[0027] In the present text, the term "(3- to 30-membered)heteroaryl" is an aryl group having 3 to 30 ring skeleton atoms and including at least one, preferably 1 to 4, heteroatoms selected from the group consisting of B, N, O, S, Si, and P. The above-mentioned heteroaryl group can be a monocyclic ring, or a fused ring condensed with at least one benzene ring; can be partially saturated; can be a heteroaryl group formed by linking at least one heteroaryl or aryl group to a heteroaryl group via one or more single bonds; and can include a spiro structure. The above-mentioned heteroaryl group can include monocyclic-type heteroaryl groups such as furyl, thienyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl, triazolyl, tetrazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, and the like, and fused ring-type heteroaryl groups such as benzofuranyl, benzothienyl, isobenzofuranyl, dibenzofuranyl, dibenzothienyl, benzonaphthofuranyl, benzonaphthothienyl, benzoimidazolyl, benzothiazolyl, naphthothiazolyl, benzoisothiazolyl, benzoisoxazolyl, benzoxazolyl, isoindolyl, indolyl, benzoindolyl, indazolyl, benzothiadiazolyl, quinolyl, isoquinolyl, cinnolinyl, quinazolinyl, benzoquinazolinyl, quinoxalinyl, benzoquinoxalinyl, naphthpyridinyl, carbazolyl, benzocarbazolyl, diphenoxazinyl, phenothiazinyl, phenanthridinyl, benzodioxolyl, dihydroacridinyl, and the like. More specifically, the heteroaryl group can include 1-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl, pyrazinyl, 2-pyridyl, 2-pyrimidinyl, 4-pyrimidinyl, 5-pyrimidinyl, 6-pyrimidinyl, 1,2,3-triazin-4-yl, 1,2,4-triazin-3-yl, 1,3,5-triazin-2-yl, 1-imidazolyl, 2-imidazolyl, 1-pyrazolyl, 1-indolinyl, 2-indolinyl, 3-indolinyl, 5-indolinyl, 6-indolinyl, 7-indolinyl, 8-indolinyl, 2-imidazopyridyl, 3-imidazopyridyl, 5-imidazopyridyl, 6-imidazopyridyl, 7-imidazopyridyl, 8-imidazopyridyl, 3-pyridyl, 4-pyridyl, 1-indolyl, 2-indolyl, 3-indolyl, 4-indolyl, 5-indolyl, 6-indolyl, 7-indolyl, 1-isoindolyl, 2-isoindolyl, 3-isoindolyl, 4-isoindolyl, 5-isoindolyl, 6-isoindolyl, 7-isoindolyl, 2-furyl, 3-furyl, 2-benzofuranyl, 3-benzofuranyl, 4-benzofuranyl, 5-benzofuranyl, 6-benzofuranyl, 7-benzofuranyl, 1-isobenzofuranyl, 3-isobenzofuranyl, 4-isobenzofuranyl, 5-isobenzofuranyl, 6-isobenzofuranyl, 7-isobenzofuranyl, 2-quinolyl, 3-quinolyl, 4-quinolyl, 5-quinolyl, 6-quinolyl, 7-quinolyl, 8-quinolyl, 1-isoquinolyl, 3-isoquinolyl, 4-isoquinolyl, 5-isoquinolyl, 6-isoquinolyl, 7-isoquinolyl, and the like.8-isoquinolyl, 2-quinoxalinyl, 5-quinoxalinyl, 6-quinoxalinyl, 1-carbazolyl, 2-carbazolyl, 3-carbazolyl, 4-carbazolyl, 9-carbazolyl, azacarbazolyl-1-yl, azacarbazolyl-2-yl, azacarbazolyl-3-yl, azacarbazolyl-4-yl, azacarbazolyl-5-yl, azacarbazolyl-6-yl, azacarbazolyl-7-yl, azacarbazolyl-8-yl, azacarbazolyl-9-yl, 1-phenanthridinyl, 2-phenanthridinyl, 3-phenanthridinyl, 4-phenanthridinyl, 6-phenanthridinyl, 7-phenanthridinyl, 8-phenanthridinyl, 9-phenanthridinyl, 10-phenanthridinyl, 1-acridinyl, 2-acridinyl, 3-acridinyl, 4-acridinyl, 9-acridinyl, 2-oxazolyl, 4-oxazolyl, 5-oxazolyl, 2-oxadiazolyl, 5-oxadiazolyl, 3-furazanyl, 2-thienyl, 3-thienyl, 2-methylpyrrolyl-1-yl, 2-methylpyrrolyl-3-yl, 2-methylpyrrolyl-4-yl, 2-methylpyrrolyl-5-yl, 3-methylpyrrolyl-1-yl, 3-methylpyrrolyl-2-yl, 3-methylpyrrolyl-4-yl, 3-methylpyrrolyl-5-yl, 2-t-butylpyrrolyl-4-yl, 3-(2-phenylpropyl)pyrrolyl-1-yl, 2-methyl-1-indolyl, 4-methyl-1-indolyl, 2-methyl-3-indolyl, 4-methyl-3-indolyl, 2-t-butyl-1-indolyl, 4-t-butyl-1-indolyl, 2-t-butyl-3-indolyl, 4-t-butyl-3-indolyl, 1-dibenzofuryl, 2-dibenzofuryl, 3-dibenzofuryl, 4-dibenzofuryl, 1-dibenzothiophenyl, 2-dibenzothiophenyl, 3-dibenzothiophenyl, 4-dibenzothiophenyl, 1-silolyl, 2-silolyl, 3-silolyl, 4-silolyl, 1-germolyl, 2-germolyl, 3-germolyl, 4-germolyl, and the like. "Halogen" includes F, Cl, Br, and I.

[0028] Further, "o-", "m-", and "p-" are prefixes that indicate the relative position of a substituent. O- indicates that two substituents are adjacent to each other, and is referred to as o- when, for example, two substituents in a benzene derivative occupy positions 1 and 2. M- indicates that two substituents are at positions 1 and 3, and is referred to as m- when, for example, two substituents in a benzene derivative occupy positions 1 and 3. P- indicates that two substituents are at positions 1 and 4, and is referred to as p- when, for example, two substituents in a benzene derivative occupy positions 1 and 4.

[0029] In this context, "substituted" in the expression "substituted or unsubstituted" means that a hydrogen atom in a certain functional group is replaced with another atom or another functional group, i.e., a substituent. In R1to R6and Ar1, the substituents of the substituted alkyl group, the substituted aryl group, and the substituted heteroaryl group are each independently at least one selected from the group consisting of deuterium; a halogen; a cyano group; a carboxyl group; a nitro group; a hydroxyl group; a (C1-C30)alkyl group; a halo(C1-C30)alkyl group; a (C2-C30)alkenyl group; a (C2-C30)alkynyl group; a (C1-C30)alkoxy group; a (C1-C30)alkylthio group; a (C3-C30)cycloalkyl group; a (C3-C30)cycloalkenyl group; a (3- to 7-membered)heterocycloalkyl group; a (C6-C30)aryloxy group; a (C6-C30)arylthio group; an unsubstituted or substituted (3- to 30-membered)heteroaryl group with one or more (C6-C30)aryl groups; an unsubstituted or substituted (C6-C30)aryl group with at least one of deuterium, one or more (C1-C30)alkyl groups, and one or more (3- to 30-membered)heteroaryl groups; a tri(C1-C30)alkylsilyl group; a tri(C6-C30)arylsilyl group; a di(C1-C30)alkyl(C6-C30)arylsilyl group; a (C1-C30)alkyldi(C6-C30)arylsilyl group; an amino group; a mono- or di- (C1-C30)alkylamino group; a mono- or di- (C6-C30)arylamino group; a (C1-C30)alkyl(C6-C30)arylamino group; a (C1-C30)alkylcarbonyl group; a (C1-C30)alkoxycarbonyl group; a (C6-C30)arylcarbonyl group; a di(C6-C30)arylboronyl group; a di(C1-C30)alkylboronyl group; a (C1-C30)alkyl(C6-C30)arylboronyl group; a (C6-C30)aryl(C1-C30)alkyl group; and a (C1-C30)alkyl(C6-C30)aryl group. According to one embodiment of the present disclosure, the substituents are each independently at least one selected from the group consisting of deuterium, a (C1-C6)alkyl group, an unsubstituted or substituted (C6-C12)aryl group with one or more deuteriums, and a (5- to 15-membered)heteroaryl group. In particular, the substituents can each independently be at least one selected from the group consisting of deuterium, a methyl group, a tert-butyl group, a phenyl group, a naphthyl group, a phenyl group substituted with one or more deuteriums, and a carbazolyl group.

[0030] The compound represented by Formula 1 can be represented by the following Formula 1-1 or 1-2:

[0031]

[0032] wherein

[0033] R1to R6, Ar1, and a to f are as defined in Formula 1, provided that d is 1 or 2 in Formula 1-1 and b is 1, 2, or 3 in Formula 1-2.

[0034] In Formula 1, Ar1represents a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (5- to 30-membered)heteroaryl. According to one embodiment of the present disclosure, Ar1is a substituted or unsubstituted (C6-C24)aryl or a substituted or unsubstituted (5- to 20-membered)heteroaryl. According to another embodiment of the present disclosure, Ar1is an unsubstituted or substituted (C6-C24)aryl substituted with one or more selected from deuterium, (C1-C6)alkyl, (C6-C12)aryl, (C6-C12)aryl substituted with deuterium, and (5- to 15-membered)heteroaryl; or an unsubstituted or substituted (5- to 20-membered)heteroaryl substituted with one or more selected from deuterium, (C6-C12)aryl, and (C6-C12)aryl substituted with deuterium. For example, Ar1may be phenyl, naphthyl, biphenyl, phenanthryl, terphenyl, triphenylenyl, naphthylphenyl, phenylnaphthyl, phenylphenanthryl, diphenylfluorenyl, diphenylbenzofluorenyl, phenyl substituted with one or more deuterium, biphenyl substituted with one or more deuterium, naphthyl substituted with one or more deuterium, phenylnaphthyl substituted with one or more deuterium, phenyl substituted with tert-butyl, dimethylfluorenyl, dimethylbenzofluorenyl, phenyl substituted with carbazolyl, dibenzofuranyl, dibenzothiophenyl, benzonaphthofuranyl, benzonaphthothiophenyl, dibenzofuranyl substituted with one or more deuterium, benzofuranyl substituted with phenyl, benzothiophenyl substituted with phenyl, benzoxazolyl substituted with phenyl, carbazolyl substituted with phenyl, naphthoxazolyl substituted with phenyl, phenylnaphthoxazolyl substituted with one or more deuterium, or the like.

[0035] In Formula 1, Ar2represents

[0036] In Formula 1, Ar2is connected to at one of positions R1to R4(* indicates a position connected to Ar2). R1to R4not connected to and R5and R6each independently represent hydrogen, deuterium, halogen, cyano, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (5- to 30-membered)heteroaryl. According to one embodiment of the present disclosure, R1to R4not connected to each independently are hydrogen, deuterium, or a substituted or unsubstituted (C6-C12)aryl, and R5and R6each independently are hydrogen or deuterium. According to another embodiment of the present disclosure, R1to R4not connected to each independently are hydrogen, deuterium, or an unsubstituted (C6-C12)aryl, and R5and R6each independently are hydrogen or deuterium. For example, R1to R4not connected to The linked R1to R4may each independently be hydrogen, deuterium, phenyl, or the like.

[0037] According to one embodiment of the present disclosure, in Formula 1, Ar1is a substituted or unsubstituted (C6-C24)aryl, or a substituted or unsubstituted (5- to 20-membered)heteroaryl; is not linked to The linked R1to R4are each independently hydrogen, deuterium, or a substituted or unsubstituted (C6-C12)aryl; and R5and R6are each independently hydrogen or deuterium.

[0038] According to another embodiment of the present disclosure, in Formula 1, Ar1is an unsubstituted or substituted (C6-C24)aryl selected from the group consisting of deuterium, one or more (C1-C6)alkyl, one or more (C6-C12)aryl, one or more (C6-C12)aryl substituted with deuterium, and one or more (5- to 15-membered)heteroaryl; or an unsubstituted or substituted (5- to 20-membered)heteroaryl selected from the group consisting of deuterium, one or more (C6-C12)aryl, and one or more (C6-C12)aryl substituted with deuterium; is not linked to The linked R1to R4are each independently hydrogen, deuterium, or a substituted or unsubstituted (C6-C12)aryl; and R5and R6are each independently hydrogen or deuterium.

[0039] In the formula of the present disclosure, if adjacent substituents are linked to each other to form a ring, the ring can be a substituted or unsubstituted monocyclic or polycyclic (3- to 30-membered)alicyclic ring or aromatic ring, or a combination thereof, wherein the formed ring can contain at least one heteroatom selected from the group consisting of B, N, O, S, Si, and P, preferably N, O, and S. According to one embodiment of the present disclosure, the number of ring skeleton atoms can be 5 to 20. According to another embodiment of the present disclosure, the number of ring skeleton atoms can be 5 to 15. For example, the fused ring can be a substituted or unsubstituted dibenzothiophene ring, a substituted or unsubstituted dibenzofuran ring, a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted phenanthrene ring, a substituted or unsubstituted fluorene ring, a substituted or unsubstituted benzothiophene ring, a substituted or unsubstituted benzofuran ring, a substituted or unsubstituted indole ring, a substituted or unsubstituted indene ring, a substituted or unsubstituted benzene ring, or a substituted or unsubstituted carbazole ring.

[0040] In the formulae of the present disclosure, the (hetero)aryl group each independently can contain at least one heteroatom selected from the group consisting of B, N, O, S, Si, and P. Further, the heteroatom can be bonded to at least one substituent selected from the group consisting of hydrogen, deuterium, halogen, cyano, a substituted or unsubstituted (C1-C30)alkyl group, a substituted or unsubstituted (C6-C30)aryl group, a substituted or unsubstituted (5- to 30-membered)heteroaryl group, a substituted or unsubstituted (C3-C30)cycloalkyl group, a substituted or unsubstituted (C1-C30)alkoxy group, a substituted or unsubstituted tri(C1-C30)alkylsilyl group, a substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl group, a substituted or unsubstituted (C1-C30)alkyl-di(C6-C30)arylsilyl group, a substituted or unsubstituted tri(C6-C30)arylsilyl group, a substituted or unsubstituted mono- or di- (C1-C30)alkylamino group, a substituted or unsubstituted mono- or di- (C6-C30)arylamino group, and a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino group.

[0041] The compound represented by Formula 1 includes the following compounds, but is not limited thereto.

[0042]

[0043]

[0044]

[0045]

[0046]

[0047] In the formula, D n means that n hydrogens in Formula 1 are replaced with deuterium. For example, in the compound C-65, it means that 1 to 26 hydrogen atoms bonded to the carbon atoms of the compound are replaced with deuterium.

[0048] The compound of Formula 1 according to the present disclosure can be prepared by synthetic methods known to one skilled in the art and, for example, as shown in the following Reaction Schemes 1 and 2, but is not limited thereto.

[0049] [Reaction Scheme 1]

[0050]

[0051] [Reaction Scheme 2]

[0052]

[0053] In Reaction Schemes 1 and 2, Ar1, R1to R6, and a to f are as defined in Formula 1, and Hal represents halogen.

[0054] Further, non-deuterated derivatives of the compound represented by Formula 1 can be prepared by known coupling or substitution reactions. The deuterated derivatives can be prepared by similar methods using deuterated precursor materials, or more generally, treating non-deuterated compounds with D6-benzene in the presence of Lewis acids such as aluminum trichloride or ethyl aluminum chloride, H / D exchange catalysts such as triflic acid or triflic acid-D, etc. Further, the degree of deuteration can be controlled by varying the reaction conditions such as reaction temperature.

[0055] Although the above describes illustrative synthesis examples of the compound represented by Formula 1, those skilled in the art will be able to readily understand that they are all based on Buchwald-Hartwig cross-coupling reaction, N-arylation reaction, H-mont-mediated etherification reaction, Miyaura borylation reaction, Suzuki cross-coupling reaction, intramolecular acid-induced cyclization reaction, Pd(II)-catalyzed oxidative cyclization reaction, Grignard reaction, Heck reaction, dehydration cyclization reaction, SN1 substitution reaction, SN2 substitution reaction, phosphine-mediated reductive cyclization reaction, etc., and even if the substituents defined in the above Formula 1 but not specified in the specific synthesis examples are bonded, the above reactions are performed.

[0056] The present disclosure provides an organic electroluminescent material including an organic electroluminescent compound represented by Formula 1, and an organic electroluminescent device including the same. The material can consist of only the organic electroluminescent compound according to the present disclosure, or can further include conventional materials included in organic electroluminescent materials.

[0057] The organic electroluminescent device according to the present disclosure includes a first electrode, a second electrode, and at least one organic layer between the first electrode and the second electrode, wherein the organic layer can include at least one organic electroluminescent compound represented by Formula 1.

[0058] One of the first electrode and the second electrode can be an anode, and the other can be a cathode. The organic layer can include an emission layer, and can further include at least one layer selected from a hole injection layer, a hole transport layer, a hole auxiliary layer, an emission auxiliary layer, an electron transport layer, an electron buffer layer, an electron injection layer, an intermediate layer, a hole blocking layer, and an electron blocking layer.

[0059] The second electrode may be a transflective electrode or a reflective electrode, and the organic electroluminescent device may be a top emission type, a bottom emission type, or a double-sided emission type according to the type of material formed.

[0060] The first electrode and the second electrode can each be formed of a transmissive conductive material, a semi-transmissive reflective conductive material, or a reflective conductive material. Depending on the type of material forming the first electrode and the second electrode, the organic electroluminescent device can be a top-emitting type, a bottom-emitting type, or a double-sided emitting type. In addition, the hole injection layer can be further doped with a p-type dopant, and the electron injection layer can be further doped with an n-type dopant.

[0061] The organic electroluminescent compound represented by Formula 1 of the present disclosure may be included in at least one of a light-emitting layer, a hole injection layer, a hole transport layer, a hole auxiliary layer, a light-emitting auxiliary layer, an electron transport layer, an electron buffer layer, an electron injection layer, an intermediate layer, a hole blocking layer, and an electron blocking layer, preferably, it may be included in a light-emitting layer. When used in a light-emitting layer, the organic electroluminescent compound represented by Formula 1 of the present disclosure may be included as a host material. Preferably, the light-emitting layer may further include at least one dopant. If necessary, the organic electroluminescent compound of the present disclosure may be used as a co-host material. That is, the light-emitting layer may further include a compound other than the organic electroluminescent compound represented by Formula 1 of the present disclosure (first host material) as a second host material. The weight ratio between the first host material and the second host material is 1:99 to 99:1.

[0062] The dopant contained in the organic electroluminescent device of the present disclosure is at least one phosphorescent dopant or fluorescent dopant, preferably at least one fluorescent dopant. The fluorescent dopant material used in the organic electroluminescent device of the present disclosure is not particularly limited.

[0063] As the dopant included in the organic electroluminescent device of the present disclosure, for example, a condensed polycyclic amine derivative represented by Formula 40 can be exemplified, but is not limited thereto.

[0064]

[0065] in

[0066] Ar 41 represents a substituted or unsubstituted (C6-C50) aryl group or styryl group; L a represents a single bond, a substituted or unsubstituted (C6-C30)arylene group, or a substituted or unsubstituted (3- to 30-membered)heteroarylene group; Ar 42 and Ar 43each independently represent hydrogen, deuterium, halogen, a substituted or unsubstituted (C1-C30)alkyl group, a substituted or unsubstituted (C6-C30)aryl group, or a substituted or unsubstituted (3- to 30-membered)heteroaryl group, or can be linked to an adjacent substituent(s) to form a (3- to 30-membered) monocyclic or polycyclic, aliphatic, aromatic, or combination thereof ring, wherein the carbon atom of the ring can be replaced with one or more hetero atoms selected from N, O, and S; jj is 1 or 2, and if jj is 2, each of may be the same or different.

[0067] Ar 41 Preferred aryl groups in Ar are a substituted or unsubstituted phenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted pyrenyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted benzofluorenyl group, a spiro[fluorene-benzofluorene], or the like.

[0068] The organic layer can further include at least one compound selected from the group consisting of arylamine-based compounds and styryl arylamine-based compounds.

[0069] Further, in the organic electroluminescent device of the present disclosure, the organic layer can further include at least one metal selected from the group consisting of a metal of Group 1 of the periodic table, a metal of Group 2, a transition metal of Period 4, a transition metal of Period 5, a lanthanide series element, and an organic metal of d-transition element, or at least one complex compound including the metal.

[0070] The organic electroluminescent device of the present disclosure can emit white light by further including at least one light-emitting layer containing a compound known in the art that emits blue, red, or green light, in addition to the organic electroluminescent compound of the present disclosure. Further, if necessary, it can further include a layer that emits yellow or orange light.

[0071] In the organic electroluminescent device of the present disclosure, at least one layer selected from a chalcogenide layer, a metal halide layer, and a metal oxide layer (hereinafter, a "surface layer") can be preferably placed on one or more of the inner surfaces of one or both electrodes. Specifically, a chalcogenide (including oxide) layer of silicon or aluminum is preferably placed on the anode surface of the electroluminescent medium layer, and a metal halide layer or a metal oxide layer is preferably placed on the cathode surface of the electroluminescent medium layer. The surface layer can provide operational stability to the organic electroluminescent device. Preferably, the chalcogenide includes SiO X (1≤X≤2), AlO X(1≤X≤1.5), SiON, SiAlON, etc.; metal halides include LiF, MgF2, CaF2, rare earth metal fluorides, etc.; and metal oxides include Cs2O, Li2O, MgO, SrO, BaO, CaO, etc.

[0072] A hole injection layer, a hole transport layer, or an electron blocking layer, or a combination thereof, can be used between the anode and the light-emitting layer. The hole injection layer can be a multi-layer in order to lower a hole injection barrier (or a hole injection voltage) from the anode to the hole transport layer or the electron blocking layer, where each of the multi-layer can use two compounds at the same time. The hole transport layer or the electron blocking layer can also be a multi-layer.

[0073] An electron buffer layer, a hole blocking layer, an electron transport layer, or an electron injection layer, or a combination thereof, can be used between the light-emitting layer and the cathode. The electron buffer layer can be a multi-layer in order to control the injection of electrons and to improve the interface properties between the light-emitting layer and the electron injection layer, where each of the multi-layer can use two compounds at the same time. The hole blocking layer or the electron transport layer can also be a multi-layer, where each of the multi-layer can use a plurality of compounds.

[0074] A light-emitting auxiliary layer can be placed between the anode and the light-emitting layer, or between the cathode and the light-emitting layer. When the light-emitting auxiliary layer is placed between the anode and the light-emitting layer, it can be used to facilitate hole injection and / or hole transport, or to prevent electron overflow. When the light-emitting auxiliary layer is placed between the cathode and the light-emitting layer, it can be used to facilitate electron injection and / or electron transport, or to prevent hole overflow. In addition, a hole auxiliary layer can be placed between the hole transport layer (or the hole injection layer) and the light-emitting layer, and can effectively facilitate or block the hole transport rate (or the hole injection rate), thereby enabling control of the charge balance. In addition, an electron blocking layer can be placed between the hole transport layer (or the hole injection layer) and the light-emitting layer, and can block overflow electrons from the light-emitting layer and confine excitons in the light-emitting layer to prevent light leakage. When an organic electroluminescent device includes two or more hole transport layers, the further included hole transport layer can function as a hole auxiliary layer or an electron blocking layer. The hole auxiliary layer and the electron blocking layer can have the effect of improving the efficiency and / or the lifespan of the organic electroluminescent device.

[0075] In the organic electroluminescent device of the present disclosure, a mixed region of an electron transport compound and a reducing dopant, or a mixed region of a hole transport compound and an oxidizing dopant is preferably placed on at least one surface of a pair of electrodes. In this case, the electron transport compound is reduced to an anion, and thus it becomes easier to inject and transport electrons from the mixed region to the electroluminescent medium. In addition, the hole transport compound is oxidized to a cation, and thus it becomes easier to inject and transport holes from the mixed region to the electroluminescent medium. Preferably, the oxidizing dopant includes various Lewis acids and acceptor compounds; and the reducing dopant includes alkali metals, alkali metal compounds, alkaline earth metals, rare earth metals, and mixtures thereof. The reducing dopant layer can be used as a charge generation layer to produce an organic electroluminescent device having two or more light-emitting layers that emit white light.

[0076] According to one embodiment of the present disclosure, the organic electroluminescent material can be used as a light-emitting material for a white organic light-emitting device. According to the arrangement of R (red), G (green), B (blue), or YG (yellow-green) light-emitting units, a white organic light-emitting device has been proposed in various structures, such as a parallel side-by-side arrangement method, a stacked arrangement method, or a CCM (color conversion material) method, etc. In addition, according to one embodiment of the present disclosure, the organic electroluminescent material can also be applied to an organic electroluminescent device containing QDs (quantum dots).

[0077] To form each layer of the organic electroluminescent device of the present disclosure, a dry film formation method such as vacuum evaporation, sputtering, plasma, ion plating, etc., or a wet film formation method such as spin coating, inkjet printing, dip coating, flow coating, etc., can be used.

[0078] When using a wet film formation method, a thin film can be formed by dissolving or diffusing the material forming each layer into any suitable solvent such as ethanol, chloroform, tetrahydrofuran, dioxane, etc. There is no particular limitation on the solvent, as long as the material forming each layer is soluble or dispersible in the solvent, which does not cause any problems in forming a film.

[0079] A display system, such as a display system for a smartphone, a tablet, a notebook, a PC, a TV, or a car; or a lighting system, such as an outdoor or indoor lighting system, can be produced by using the organic electroluminescent device of the present disclosure.

[0080] Hereinafter, the preparation method of the compound of the present disclosure, and the properties of the compound, and the light-emitting properties of the organic electroluminescent device containing the compound will be explained in detail with reference to representative compounds of the present disclosure. However, the present disclosure is not limited to the following examples.

[0081] Example 1: Preparation of compound C-1

[0082]

[0083] Compound A-1 (10.5 g, 0.029 mol), compound A-2 (8.9 g, 0.032 mol), Pd(OAc)2(0.33 g, 0.001 mol), s-phos (1.2 g, 0.002 mmol), K2CO3(12.1 g, 0.088 mol), 26 mL of acetonitrile, 52 mL of distilled water, and 126 mL of toluene were added to a flask and stirred at 120°C for 16 hours. The mixture was cooled to room temperature, extracted with ethyl acetate (EA), and the organic layer was washed with distilled water. The obtained organic layer was distilled under reduced pressure and separated by column chromatography to obtain compound C-1 (4 g, 26.5%).

[0084] MW Melting point C-1 530.20 394℃

[0085] Example 2: Preparation of compound C-35

[0086]

[0087] 1) Preparation of compound B-3

[0088] Compound 9-bromoanthracene (20 g, 0.077 mol), compound B-4 (25.1 g, 0.085 mol), Pd(PPh3)4(4.5 g, 0.003 mol), K2CO3(32 g, 0.23 mol), 97 mL of ethanol, 97 mL of distilled water, and 390 mL of toluene were added to a flask and stirred at 100°C. After 12 hours, the mixture was cooled to room temperature, extracted with dichloromethane, and the organic layer was washed with distilled water. The obtained organic layer was distilled under reduced pressure and separated by column chromatography to obtain compound B-3 (25.8 g, 96.6%).

[0089] 2) Preparation of compound B-2

[0090] Compound B-3 (25.8 g, 0.074 mol) was added to a flask, dissolved in 374 mL of dimethylformamide (DMF), and N-bromosuccinimide (13.3 g, 0.074 mol) was added thereto. The mixture was stirred at room temperature for 18 hours, extracted with dichloromethane, and the organic layer was washed with distilled water. The obtained organic layer was distilled under reduced pressure and separated by column chromatography to obtain compound B-2 (30 g, 94.6%).

[0091] 3) Preparation of compound B-1

[0092] Compound B-2 (30 g, 0.070 mol) was added to a flask, and 700 mL of tetrahydrofuran was added thereto. N-BuLi (37 mL, 2.5 M, 0.092 mol) was slowly added at -78°C. After 10 minutes, trimethyl borate (10.3 mL, 0.092 mol) was added thereto. After stirring the mixture for 12 hours, distilled water was added thereto. The organic layer was extracted with ethyl acetate, and the remaining moisture was removed using magnesium sulfate. The organic layer was distilled under reduced pressure, and solidified by adding hexane to obtain compound B-1 (16 g, 58.8%).

[0093] 4) Preparation of compound C-35

[0094] Compound A-1 (6 g, 0.016 mol), compound B-1 (8.4 g, 0.021 mol), Pd(PPh3)4 (0.97 g, 0.00084 mol), K2CO3 (6.9 g, 0.050 mol), 20 mL of ethanol, 20 mL of distilled water, and 84 mL of toluene were added to a flask and the mixture was stirred at 130°C. After 16 hours, the mixture was cooled to room temperature, extracted with ethyl acetate, and the organic layer was washed with distilled water. The obtained organic layer was distilled under reduced pressure and separated by column chromatography to obtain compound C-35 (5.5 g, 52.7%).

[0095] MW Melting point C-35 620.75 347℃

[0096] Device Example 1: Production of an OLED comprising a compound according to the present disclosure

[0097] An OLED using an organic electroluminescent compound according to the present disclosure was produced as follows: A transparent electrode indium tin oxide (ITO) thin film (10 Ω / sq) on a glass substrate for an OLED (GEOMATEC CO., LTD., Japan) was subjected to ultrasonic washing with acetone, ethanol, and distilled water, sequentially, and then stored in isopropanol. The ITO substrate was mounted on a substrate holder of a vacuum vapor deposition device. Compound HI-1 was introduced into a cell of the vacuum vapor deposition device, and then the pressure in the chamber of the device was controlled to 10 -6After that, current was applied to the cell to evaporate the above- introduced material, thereby forming a first hole injection layer having a thickness of 60 nm on the ITO substrate. Next, compound HI-2 was introduced into another cell of the vacuum vapor deposition apparatus, and the compound was evaporated by applying current to the cell, thereby forming a second hole injection layer having a thickness of 5 nm on the first hole injection layer. Then, compound HT-1 was introduced into another cell of the vacuum vapor deposition apparatus, and the compound was evaporated by applying current to the cell, thereby forming a first hole transport layer having a thickness of 20 nm on the second hole injection layer. Then, compound HT-2 was introduced into another cell of the vacuum vapor deposition apparatus, and the compound was evaporated by applying current to the cell, thereby forming a second hole transport layer having a thickness of 5 nm on the first hole transport layer. After the formation of the hole injection layer and the hole transport layer, a light-emitting layer was formed thereon as follows: compound C-1 was introduced into one cell of the vacuum vapor deposition apparatus as a host of the light-emitting layer, and compound BD was introduced into another cell. The two materials were evaporated at different rates and the dopant was deposited at a doping amount of 2 wt% based on the total amount of the host and the dopant to form a light-emitting layer having a thickness of 20 nm on the second hole transport layer. Next, compound ET-1 and compound EI-1 were evaporated at a rate of 1:1, respectively, at an amount of 50 wt% in the other two cells to deposit an electron transport layer having a thickness of 35 nm on the light-emitting layer. After depositing compound EI-1 as an electron injection layer having a thickness of 2 nm on the electron transport layer, an Al cathode having a thickness of 80 nm was deposited on the electron injection layer by another vacuum vapor deposition apparatus. Thus, an OLED was produced.

[0098] Device Example 2: Production of an OLED comprising a compound according to the present disclosure

[0099] An OLED was produced in the same manner as in Device Example 1 except that compound C-35 was used instead of compound C-1 as a host material of the light-emitting layer.

[0100] Comparative Example: Production of an OLED comprising a conventional compound

[0101] An OLED was produced in the same manner as in Device Example 1 except that compound BH-1 was used instead of compound C-1 as a host material of the light-emitting layer.

[0102] As a result, the measurement results of the driving voltage, current efficiency, and electroluminescent wavelength of the organic electroluminescent devices of Device Examples 1 and 2 and Comparative Examples based on a luminance of 1,000 nits are shown in Table 1 below.

[0103] [Table 1]

[0104]

[0105] As can be seen from Table 1 above, the organic electroluminescent device including the organic electroluminescent compound according to the present disclosure as a host material exhibits a lower driving voltage and significantly improved current efficiency characteristics when compared to devices using comparative compounds.

[0106] The compounds used in the device examples and comparative examples are shown in Table 2 below.

[0107] [Table 2]

[0108]

Claims

1. An organic electroluminescent compound, which is represented by the following formula 1: in Formula 1 is represented by the following formula 1-1: Ar1 represents a deuterium-substituted or unsubstituted (C6-C24) aryl group, or a deuterium-substituted or unsubstituted (5- to 20-membered) heteroaryl group; R5 and R6 each independently represent hydrogen or deuterium; Not with R1 to R4 connected each independently represent hydrogen or deuterium; a and d each independently represent an integer from 1 to 3, and b, c, e and f each independently represent an integer from 1 to 4; Wherein if a to f are integers of 2 or greater, each R1 to each R6 may be the same as or different from each other.

2. An organic electroluminescent compound, wherein the organic electroluminescent compound is selected from the group consisting of the following compounds: Among them D n This means that n hydrogen atoms in Formula 1 are replaced by deuterium atoms. 3 . An organic electroluminescent material comprising the organic electroluminescent compound according to claim 1 . 4 . An organic electroluminescent device comprising the organic electroluminescent compound according to claim 1 .

5. The organic electroluminescent device according to claim 4, wherein: The organic electroluminescent compound is contained in the light-emitting layer.

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