Materials for organic electroluminescent devices

Abstract

This invention relates to compounds comprising heterocyclic groups substituted with fluoranthene groups and specific aromatic or heteroaromatic groups. These compounds are suitable for use in electronic devices, particularly organic electroluminescent devices. In some embodiments, the compounds are used as matrix materials for phosphorescent or fluorescent emitters, as well as hole-blocking layers or electron transport layers.

Description

[0001] This invention relates to materials used in electronic devices, particularly organic electroluminescent devices, and to electronic devices, particularly organic electroluminescent devices, incorporating these materials.

[0002] The structures of organic light-emitting diodes (OLEDs) utilizing organic semiconductors as functional materials are described in, for example, US4539507, US 5151629, EP 0676461, and WO 98 / 27136. The luminescent materials used here are increasingly organometallic complexes that exhibit phosphorescence rather than fluorescence. Due to quantum mechanical reasons, using organometallic compounds as phosphorescent emitters can result in up to a fourfold increase in energy and power efficiency. However, in general, improvements are still needed in the case of OLEDs, especially in the case of OLEDs that also exhibit triplet emission (phosphorescence), such as improvements in efficiency, operating voltage, and lifetime.

[0003] The properties of phosphorescent OLEDs are determined not only by the triplet emitter used. In particular, other materials used, such as matrix materials, hole-blocking materials, electron transport materials, and electron or exciton-blocking materials, are also particularly important. Improvements in these materials can therefore lead to significant improvements in OLED properties, especially in terms of efficiency, lifetime, and thermal stability.

[0004] The object of this invention is to provide compounds suitable for use in OLEDs, particularly as matrix materials for phosphorescent emitters, but also as hole-blocking materials, electron transport materials, or optionally as materials for charge-generating layers. Another object of this invention is to provide other organic semiconductors for organic electroluminescent devices, thereby providing those skilled in the art with more feasible options for materials used in the manufacture of OLEDs.

[0005] Compounds with aromatic heterocyclic groups such as dibenzofuran and dibenzothiophene are known to be used in OLEDs, generally as the host for luminescent materials or for their charge-carrying properties. Dibenzofuran or dibenzothiophene can be substituted with substituents such as aromatic or heteroaromatic groups to obtain compounds with suitable charge-carrying properties.

[0006] EP 2372803, CN 102850334, and EP 1885818 describe OLEDs comprising compounds having aromatic groups, heteroaromatic groups, or arylamine groups, said groups being bonded to a dibenzofuran skeleton or a dibenzothiophene skeleton.

[0007] US 2012 / 0119196, WO 2013 / 132278, WO 2015 / 050173 and US 2015 / 0108449 describe OLEDs containing compounds having a fluoranthene ring bonded to an aromatic heterocyclic group.

[0008] Surprisingly, compounds containing dibenzofuran or dibenzothiophene groups have been found to achieve excellent performance data, said dibenzofuran or dibenzothiophene groups being directly bonded to a fluoranthene skeleton on one side and directly bonded to specific aromatic or heteroaromatic groups on the other side. More particularly, the compounds of the present invention, described in more detail below, are well-suited for use in OLEDs and result in improvements in efficiency, lifetime, and / or operating voltage of organic electroluminescent devices. These improvements are particularly related to luminous efficiency. More specifically, OLEDs containing the compounds of the present invention as a matrix material or host in the luminescent layer for red or yellow phosphorescent emitters (triplet T1 between 2.4 eV and 1.8 eV) exhibit improved luminous efficiency while maintaining very good properties in terms of operating voltage and lifetime. Therefore, the present invention relates to these compounds and to electronic devices, particularly organic electroluminescent devices, containing compounds of the following types.

[0009] Therefore, the present invention relates to compounds of formula (1) or formula (2).

[0010]

[0011] The following definitions apply to the symbols and tags used:

[0012] X is O or S;

[0013] Ar S It is an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, wherein the aromatic or heteroaromatic ring system may in each case be further divided by one or more R 3 Group substitution;

[0014] Ar is a fused aryl group having 10 to 40 aromatic ring atoms, wherein in each case the fused aryl group can be fused with one or more R atoms. 3 Group substitution; or Ar is a group of formula (Ar-1),

[0015]

[0016] The condition is that Ar is not fluoranthene; and the dashed line indicates that Ar is not fluoranthene. S The bonded bond, or if Ar S If not, the dashed line represents a bond bonded to a phenyl group of a heterocycle containing X as described in formula (1) or formula (2);

[0017] E is O, S, C(R) 0 )2; where when t is 0, the bivalent bridge basis E does not exist;

[0018] R 0 R 1 R 2 R, which appears the same or different each time, is: H, D, F, Cl, Br, I, CHO, C(=O)Ar 1 , P(=O)(Ar 1 )2, S(=O)Ar 1 S(=O)2Ar 1 , (R 4 C = C(R) 4 )Ar 1 CN, NO2, N(R) 4 )2,Si(R 4 3, B(OR) 4 )2, B(R) 4 )2, B(N(R 4 )2)2,OSO2R 4 The group comprises a straight-chain alkyl, alkoxy, or thioalkoxy group having 1 to 40 carbon atoms, or a straight-chain alkenyl or alkynyl group having 2 to 40 carbon atoms, or a branched or cyclic alkyl, alkenyl, alkynyl, or thioalkoxy group having 3 to 40 carbon atoms, each of which may be expressed by one or more R groups. 4 Group substitution, wherein one or more preferably non-adjacent CH2 groups may be (R 4 C = C(R) 4 C≡C, Si(R) 4 )2、Ge(R 4 )2、Sn(R 4 )2. C=O, C=S, C=Se, P(=O)(R 4 SO, SO2, N(R) 4 ), O, S or CON (R) 4 The system may be substituted with one or more of the following: D, F, Cl, Br, I, CN, or NO2; or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, wherein in each case the aromatic or heteroaromatic ring system may be substituted with one or more of the following: R 4 The aryloxy or heteroaryloxy group is substituted with a group, or has 5 to 60 aromatic ring atoms, wherein the aryloxy or heteroaryloxy group may be substituted with one or more R groups. 4 Group substitution; two adjacent R groups 0 Substituents, two or more adjacent R 1 Substituents, two or more adjacent R 2 Substituents and / or two or more adjacent R3 Substituents can also form monocyclic or polycyclic aliphatic, aromatic, or heterocyclic ring systems with each other;

[0019] Ar 1 Each occurrence is either identical or different, consisting of an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms, wherein the aromatic or heteroaromatic ring system may in each case be one or more R 4 Group substitution;

[0020] R 4 Each occurrence is selected from H, D, F, Cl, Br, I, CN, Si(R) in the same or different manner. 5 )3, a straight-chain alkyl, alkoxy, or thioalkyl group having 1 to 40 carbon atoms, or a branched or cyclic alkyl, alkoxy, or thioalkyl group having 3 to 40 carbon atoms, wherein the group may be composed of one or more R 5 Group substitution, wherein one or more non-adjacent CH2 groups can each be replaced by C(R) groups. 5 )=C(R 5 ), Si(R) 5 2. C = NR 5 P(=O)(R) 5 SO, SO2, NR 5 O, S or CONR 5 Replacement, wherein one or more hydrogen atoms may be replaced by D, F, Cl, Br or I, having 6 to 40 C atoms and being replaceable by one or more R atoms 5 Aromatic or heteroaromatic ring systems with substituted groups, having 5 to 40 aromatic ring atoms and substituted with one or more R groups. 5 A group-substituted aryloxy group, or a group having 5 to 40 aromatic ring atoms and being substituted with one or more R groups. 5 A group-substituted aralkyl group, wherein two or more adjacent R groups are optionally present. 4 Substituents can form monocyclic or polycyclic aliphatic, aromatic, or heterocyclic ring systems with each other;

[0021] R 5 Selected from H, D, F, aliphatic hydrocarbon groups having 1 to 20 carbon atoms, or aromatic or heteroaromatic ring systems having 5 to 30 carbon atoms, wherein two or more adjacent R groups 5 Substituents can form monocyclic or polycyclic aliphatic, aromatic, or heterocyclic ring systems with each other;

[0022] m, n, r, and u are each the same or different from 0, 1, 2, or 3;

[0023] p and t are either 0 or 1, respectively;

[0024] q and v are either the same or different from 0, 1, 2, 3 or 4;

[0025] s is 0, 1, or 2.

[0026] For the purposes of this invention, the following definitions of chemical groups shall apply:

[0027] The aryl group in the sense of this invention contains 6 to 60 aromatic ring atoms; the heteroaryl group in the sense of this invention contains 5 to 60 aromatic ring atoms, wherein at least one ring atom is a heteroatom. Preferably, the heteroaryl group does not contain more than 3 heteroatoms in the ring. The heteroatoms are preferably selected from N, O, and S. This represents the basic definition. If other preferred definitions are indicated in the description of this invention, for example, regarding the number of aromatic ring atoms or heteroatoms present, these preferred definitions shall apply.

[0028] The aryl group or heteroaryl group referred to herein means a simple aromatic ring, i.e., benzene, or a simple heteroaryl ring, such as pyridine, pyrimidine, or thiophene, or a fused (enhanced) aromatic or heteroaryl polycyclic ring, such as naphthalene, phenanthrene, quinoline, or carbazole. In the sense of this application, a fused (enhanced) aromatic or heteroaryl polycyclic ring consists of two or more simple aromatic or heteroaryl rings fused together.

[0029] Specifically, in each case, the aryl or heteroaryl group that can be substituted by the groups mentioned above and can be linked to the aromatic or heteroaryl ring system via any desired position refers to a group derived from the following substances: benzene, naphthalene, anthracene, phenanthrene, pyrene, dihydropyrene, Perylene, fluoranthene, benzo[a]anthene, benzo[a]phenanthrene, tetraphenyl, pentaphenyl, benzo[a]pyrene, furan, benzo[a]furan, isobenzo[a]furan, dibenzo[a]furan, thiophene, benzo[a]thiophene, isobenzo[a]thiophene, dibenzo[a]thiophene, pyrrole, indole, isoindole, carbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline, phenothiazine, phenanthrene Azides, pyrazoles, indazoles, imidazoles, benzimidazoles, naphthiazoles, phenanthreneimidazoles, pyridiniumimidazoles, pyraziniumimidazoles, quinoxalineimidazoles azole, benzo[ azole, naphtho azole, anthraquinone azole, phenanthrene azole, isotonic azole, 1,2-thiazole, 1,3-thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine, benzopyrimidine, quinoxaline, pyrazine, phenazine, naphthidine, azacarbazole, benzocarbline, phenanthroline, 1,2,3-triazole, 1,2,4-triazole, benzotriazole, 1,2,3- diazole, 1,2,4- diazole, 1,2,5- diazole, 1,3,4- Diazole, 1,2,3-thiadiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thiadiazole, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, tetrazolium, 1,2,4,5-tetraazine, 1,2,3,4-tetraazine, 1,2,3,5-tetraazine, purine, pteridine, indene, and benzothiadiazole.

[0030] According to the present invention, an aryl group is an aryl group as defined above, bonded via an oxygen atom. A similar definition applies to heteroaryl groups.

[0031] The aromatic ring system in the sense of this invention contains 6 to 60 carbon atoms. The heteroaromatic ring system in the sense of this invention contains 5 to 60 aromatic ring atoms, wherein at least one ring atom is a heteroatom. The heteroatom is preferably selected from N, O, and / or S. The aromatic or heteroaromatic ring system in the sense of this invention is intended to represent a system that does not necessarily contain only aryl or heteroaromatic groups, but in which multiple aryl or heteroaromatic groups can also be derived from non-aromatic units (preferably less than 10% of non-H atoms), such as sp... 3 -Hybridized C, Si, N, or O atoms, sp 2 -Hybridized C or N atoms or sp-hybridized C atoms are connected. Therefore, systems in which two or more aryl groups are connected, for example, by straight-chain or cyclic alkyl, alkenyl or alkynyl groups or by silyl groups, such as 9,9'-spirodifluorene, 9,9'-diarylfluorene, triarylamine, diaryl ether, stilbene, etc., are also considered aromatic ring systems in the sense of this invention. In addition, systems in which two or more aryl or heteroaryl groups are connected to each other by single bonds, such as biphenyl, terphenyl, or diphenyltriazine, are also considered aromatic or heteroaromatic ring systems in the sense of this invention.

[0032] Specifically, an aromatic or heteroaromatic ring system having 5-60 aromatic ring atoms (which in each case may be substituted by groups as defined above and may be linked to the aromatic or heteroaromatic groups at any desired position) refers to groups derived from the following substances: benzene, naphthalene, anthracene, benzo[a]anthracene, phenanthrene, benzo[a]phenanthrene, pyrene, Perylene, fluoranthene, tetraphenylene, pentaphenylene, benzo[a]pyrene, biphenyl, biphenylene, terphenyl, terphenylene, tetraphenylene, fluorene, spirodifluorene, dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis-indo[a]fluorene or trans-indo[a]fluorene, trimer indene, isotrimer indene, spirotrimer indene, spiroisotrimer indene, furan, benzo[a]furan, isobenzo[a]furan, dibenzo[a]furan, thiophene, benzo[a]thiophene, isobenzo[a]thiophene, dibenzo[a]thiophene, pyrrole, indole, isoindole, carbazole, indole[a]carbazole, indole[a]carbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline, phenothiazine, phenanthrene Azides, pyrazoles, indazoles, imidazoles, benzimidazoles, naphthiazoles, phenanthreneimidazoles, pyridiniumimidazoles, pyraziniumimidazoles, quinoxalineimidazoles azole, benzo[ azole, naphtho azole, anthraquinone azole, phenanthrene azole, isotonic Azole, 1,2-thiazole, 1,3-thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine, benzopyrimidine, quinoxaline, 1,5-diazathane, 2,7-diazapyrene, 2,3-diazapyrene, 1,6-diazapyrene, 1,8-diazapyrene, 4,5-diazapyrene, 4,5,9,10-tetraazaperylene, pyrazine, phenazine, phenazine Azides, phenothiazines, fluorescent rings, naphthidine, azacarbazole, benzo[a]carbline, phenanthroline, 1,2,3-triazoles, 1,2,4-triazoles, benzo[a]triazoles, 1,2,3- diazole, 1,2,4- diazole, 1,2,5- diazole, 1,3,4- Diazole, 1,2,3-thiadiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thiadiazole, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, tetrazolium, 1,2,4,5-tetraazine, 1,2,3,4-tetraazine, 1,2,3,5-tetraazine, purine, pteridine, indene and benzothiadiazole, or combinations of these groups.

[0033] For the purposes of this invention, a straight-chain alkyl group having 1 to 40 carbon atoms, or a branched or cyclic alkyl group having 3 to 40 carbon atoms, or an alkenyl or alkynyl group having 2 to 40 carbon atoms (wherein each H atom or CH2 group may also be substituted by a group mentioned under the definition of the group described above) preferably refers to the following groups: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, 2-methyl butyl, n-pentyl, sec-pentyl, cyclopentyl, neopentyl, n-hexyl, cyclohexyl, neohexyl, n-heptyl, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl, trifluoromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, vinyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, ethynyl, propynyl, butynyl, pentynyl, hexynyl, or ocynyl. The alkoxy or thioalkyl group having 1 to 40 carbon atoms is preferably methyl methoxy, trifluoromethoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentoxy, sec-pentoxy, 2-methylbutoxy, n-hexyloxy, cyclohexyloxy, n-heptoxy, cycloheptoxy, n-octoxy, cyclooctoxy, 2-ethylhexyloxy, pentafluoroethoxy, 2,2,2-trifluoroethoxy, methylthio, ethylthio, n-propylthio, isopropylthio, n-butylthio, isobutylthio, sec-butylthio Thioyl, tert-butylthioyl, n-pentylthioyl, sec-pentylthioyl, n-hexylthioyl, cyclohexylthioyl, n-heptylthioyl, cycloheptylthioyl, n-octylthioyl, cyclooctylthioyl, 2-ethylhexylthioyl, trifluoromethylthioyl, pentafluoroethylthioyl, 2,2,2-trifluoroethylthioyl, ethylene thioyl, propylene thioyl, butene thioyl, pentene thioyl, cyclopentene thioyl, hexene thioyl, cyclohexene thioyl, heptene thioyl, cycloheptene thioyl, octene thioyl, cyclooctene thioyl, ethynylthioyl, propynylthioyl, butynylthioyl, pentynylthioyl, hexynylthioyl, heptynylthioyl, or octyynylthioyl.

[0034] For the purposes of this invention, the statement that two or more groups can form a ring with each other specifically refers to two groups being connected to each other by chemical bonds. This is exemplified by the following scheme:

[0035]

[0036] However, the above statement also indicates that, when one of the two groups represents hydrogen, the second group is bonded at the site where the hydrogen atom is bonded, thereby forming a ring. This is illustrated by the following scheme:

[0037]

[0038] According to a preferred embodiment, p equals 0, thereby making Ar S It does not exist, and Ar is directly bonded to a phenyl group containing a heterocycle as described in formula (1) or formula (2).

[0039] If p = 1, then Ar S The group is preferably selected from aromatic or heteroaromatic ring systems having 5 to 18 aromatic ring atoms, and in each case, the aromatic or heteroaromatic ring system may also be composed of one or more R groups. 3 Group substitution.

[0040] Specially selected Ar S The groups are selected from the following formula (Ar S -1) to formula (Ar S -13):

[0041]

[0042] The dashed bond indicates a bond to a phenyl group containing an X-containing heterocycle as described in formula (1) or (2) and a bond to an Ar group as described in formula (1) or (2), wherein the group can be R at each free position. 3 The group may be substituted, but preferably the group is unsubstituted.

[0043] In a preferred embodiment of the present invention, the compound of formula (1) or formula (2) is selected from the compounds of formula (1-1) or formula (2-1).

[0044]

[0045] The symbols and markings used have the same meaning as those mentioned above.

[0046] In a particularly preferred embodiment of the invention, the compound of formula (1-1) or formula (2-1) is selected from the compounds of formulas (1-1-1) to (2-1-4).

[0047]

[0048]

[0049] The symbols and markings used have the same meaning as those mentioned above.

[0050] In a particularly preferred embodiment of the invention, the compounds of formulas (1-1-1) to (2-1-4) are selected from the compounds of formulas (1-1-1-a) to (2-1-4-d).

[0051]

[0052]

[0053]

[0054]

[0055] The symbols and markings used have the same meaning as those mentioned above.

[0056] According to the present invention, preferred formula (1), very preferred formula (1-1), particularly preferred formula (1-1-1) to formula (1-1-4), and very particularly preferred formula (1-1-1-a) to formula (1-1-4-d).

[0057] The Ar group in formulas (1), (2), (1-1), (2-1), (1-1-1) to (2-1-4) and (1-1-1-a) to (2-1-4-d) is a fused aryl group having 10 to 40 aromatic ring atoms, more preferably 14 to 40 aromatic ring atoms, wherein the Ar group in each case may be composed of one or more R groups. 3 Group substitution; or Ar is a group of formula (Ar-1) as defined above, provided that Ar is not fluoranthene.

[0058] More preferably, the Ar group is selected from naphthalene, anthracene, tetraphenylene, phenanthrene, etc. Triphenylene, pyrene, perylene, benzo[a]phenanthrene, benzo[a]pyrene, biphenyl, fluorene, spirodifluorene, dibenzofuran, dibenzothiophene, each of which can be oxidized by one or more R 3 Group substitution. Particularly preferred are Ar groups selected from anthracene, phenanthrene, and tetraphenylene. Triphenylene, fluorene, dibenzofuran, or dibenzothiophene, each of which can be produced by one or more R 3 Group substitution.

[0059] Suitable Ar groups are those of formulas (Ar-2) to (Ar-38), wherein R 0 It has the same meaning as above, and wherein the groups of formulas (Ar-2) to (Ar-38) can be one or more R as defined above. 3 The group is substituted at any free position.

[0060]

[0061]

[0062] In a preferred embodiment of the present invention, R 1 R 2 and R 3 Each group, selected identically or differently from H, D, F, CN, is a straight-chain alkyl or alkoxy group having 1 to 10 carbon atoms or a branched or cyclic alkyl or alkoxy group having 3 to 10 carbon atoms, and each of these groups may be represented by one or more R... 4A group substitution in which one or more non-adjacent CH2 groups can be replaced by O, and one or more H atoms can be replaced by F, an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms, wherein in each case the aromatic or heteroaromatic ring system can be replaced by one or more R groups. 4 Group substitution.

[0063] In a more preferred embodiment of the present invention, R 1 R 2 and R 3 Each occurrence thereof is identical or different from H, D, F, CN, a straight-chain alkyl group having 1 to 5 carbon atoms or a branched or cyclic alkyl group having 3 to 5 carbon atoms, each of which may be derived from one or more R... 4 Group substitution, wherein one or more H atoms can be replaced by F, aryl or heteroaryl groups having 5 to 14 aromatic ring atoms, wherein in each case the aryl or heteroaryl group can be replaced by one or more R atoms. 4 Group substitution.

[0064] In a particularly preferred embodiment of the present invention, R 1 R 2 and R 3 Each time it appears, it is selected from H, D, F, CN, methyl, tert-butyl, phenyl, or naphthyl, and each of the groups can be represented by one or more R groups. 4 Group substitution.

[0065] In a preferred embodiment of the present invention, R 0 Each group, selected identically or differently from H, D, F, CN, is a straight-chain alkyl or alkoxy group having 1 to 10 carbon atoms or a branched or cyclic alkyl or alkoxy group having 3 to 10 carbon atoms, and each of these groups may be represented by one or more R... 4 Group substitution, wherein in each case one or more non-adjacent CH2 groups may be replaced by O, and wherein one or more H atoms may be replaced by D, F, or CN, an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms, wherein in each case one or more R groups may be replaced by O. 4 Group substitution, where two R groups are substituted. 0 The substituents may optionally form monocyclic or polycyclic, aliphatic or aromatic or heterocyclic ring systems.

[0066] More preferably, R 0 Each occurrence thereof is selected from H, either identically or differently, of a straight-chain alkyl group having 1 to 5 carbon atoms or a branched or cyclic alkyl group having 3 to 5 carbon atoms, each of which may be derived from one or more R groups. 4Group substitution, wherein one or more H atoms can be replaced by F, aryl or heteroaryl groups having 5 to 14 aromatic ring atoms, wherein in each case the aryl or heteroaryl group can be replaced by one or more R atoms. 4 Group substitution, where two R groups are substituted. 0 The substituents may optionally form monocyclic or polycyclic, aliphatic or aromatic or heteroaromatic ring systems, which may be substituted by one or more groups.

[0067] R is the preferred choice 0 It is methyl or phenyl.

[0068] For compounds processed by vacuum evaporation, the alkyl group preferably has no more than 4 carbon atoms, and particularly preferably no more than 1 carbon atom. For compounds processed from solution, suitable compounds also include those substituted with straight-chain, branched, or cyclic alkyl groups having up to 10 carbon atoms, or those substituted with oligomeric aryl groups such as ortho-, meta-, para-, or branched terphenyl or tetraphenyl groups.

[0069] The following examples represent some compounds according to formula (1) or formula (2):

[0070]

[0071]

[0072]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081] The present invention also relates to a method for preparing compounds of formula (1) or formula (2), the method comprising the following reaction steps:

[0082] a. Dibenzofurans or dibenzothiophenes react with Ar groups as defined above in CC couplings such as Suzuki, Negishi, Yamamoto, Grignard-Cross, Stille couplings, and Ullmann couplings, or with Ar groups when p = 1. S Group reactions;

[0083] b. React the compound obtained in step a in a CC coupling such as Suzuki, Negishi, Yamamoto, or Grignard-Cross to add a fluoranthene group to the dibenzothiophene or dibenzofuran skeleton.

[0084] The materials of the present invention can generally be prepared according to the following synthesis scheme 1 or 2.

[0085] Option 1:

[0086]

[0087] Option 2:

[0088]

[0089] For processing the compounds according to the invention from a liquid phase (e.g., by spin coating or printing), formulations of the compounds according to the invention are necessary. These formulations can be, for example, solutions, dispersions, or emulsions. A mixture of two or more solvents is preferably used for this purpose. Suitable and preferred solvents include, for example: toluene, anisole, o-xylene, m-xylene or p-xylene, methyl benzoate, 1,3,5-trimethylbenzene, tetrahydronaphthalene, veratrine ether, THF, methyl-THF, THP, chlorobenzene, dichlorobenzene, etc. Alkane, phenoxytoluene, especially 3-phenoxytoluene, (-)-fonone, 1,2,3,5-tetramethylbenzene, 1,2,4,5-tetramethylbenzene, 1-methylnaphthalene, 2-methylbenzothiazole, 2-phenoxyethanol, 2-pyrrolidone, 3-methylanisole, 4-methylanisole, 3,4-dimethylanisole, 3,5-dimethylanisole, acetophenone, α-terpineol, benzothiazole, butyl benzoate, cumene, cyclohexanol, cyclohexanone, cyclohexylbenzene, decahydronaphthalene, dodecyl Alkylbenzene, ethyl benzoate, indene dihydrogen benzoate, hexamethyl indene dihydrogen benzoate, methyl benzoate, NMP, p-cymene, phenethyl ether, 1,4-diisopropylbenzene, dibenzyl ether, diethylene glycol butyl methyl ether, triethylene glycol butyl methyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, diethylene glycol monobutyl ether, tripropylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 2-isopropylnaphthalene, pentylbenzene, hexylbenzene, heptylbenzene, octylbenzene, 1,1-bis(3,4-dimethylphenyl)ethane, or mixtures of these solvents.

[0090] Therefore, the present invention also relates to formulations comprising the compounds of the present invention and at least one other compound. The other compound may be, for example, a solvent, particularly one of the solvents mentioned above or a mixture of these solvents. However, the other compound may also be at least one other organic or inorganic compound also used in the electronic device, such as a luminescent compound and / or other matrix material. Suitable luminescent compounds and other matrix materials are indicated below in conjunction with organic electroluminescent devices. The other compound may also be polymerized.

[0091] The compounds according to the invention are suitable for use in electronic devices, particularly in organic electroluminescent devices. Therefore, the invention also relates to the use of the compounds according to the invention in electronic devices, particularly in organic electroluminescent devices. Furthermore, the invention relates to electronic devices comprising at least one compound according to the invention.

[0092] In the context of this invention, an electronic device is a device comprising at least one layer, said layer comprising at least one organic compound. The component may also comprise inorganic materials or a layer composed entirely of inorganic materials. The electronic device is preferably selected from organic light-emitting devices (OLEDs), organic integrated circuits (O-ICs), organic field-effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors (O-LETs), organic solar cells (O-SCs), dye-sensitized organic solar cells (DSSCs), organic photodetectors, organic photoreceptors, organic field quenching devices (O-FQDs), light-emitting electrochemical cells (LECs), organic laser diodes (O-lasers), and "organic plasma emitting devices," but organic light-emitting devices (OLEDs) are preferred, and phosphorescent OLEDs are particularly preferred.

[0093] The organic electroluminescent device comprises a cathode, an anode, and at least one emitting layer. In addition to these layers, it may also include other layers, such as one or more hole injection layers, hole transport layers, hole blocking layers, electron transport layers, electron injection layers, exciton blocking layers, electron blocking layers, and / or charge generation layers in each case. An intermediate layer having, for example, exciton blocking functionality may also be introduced between the two emitting layers. However, it should be noted that each of these layers is not necessarily required. The organic electroluminescent device herein may comprise one emitting layer, or it may comprise multiple emitting layers. If multiple emitting layers are present, these emitting layers preferably have a total of multiple emission peaks between 380 nm and 750 nm, resulting in overall white light emission, i.e., using multiple luminescent compounds capable of fluorescence or phosphorescence in the emitting layers. Particularly preferred are systems with two emitting layers, wherein the two layers emit blue and orange or yellow light, or three emitting layers, wherein the three layers emit blue, green, and orange or red light (for the basic structure, see, for example, WO 2005 / 011013). The organic electroluminescent device according to the present invention can also be a tandem OLED, and in particular, it is also used for white light emitting OLEDs.

[0094] Depending on the specific structure, the compounds of the present invention according to the above embodiments can be used in different layers of electronic devices. Depending on the specific substitution, preferred organic electroluminescent devices comprise compounds of formula (1) or formula (2) or the preferred embodiments described above, said compounds serving as matrix materials for fluorescent or phosphorescent emitters, particularly for phosphorescent emitters, and / or applied in electron blocking or exciton blocking layers and / or in charge generating layers and / or in hole blocking or electron transport layers.

[0095] In a preferred embodiment of the invention, the compound according to the invention is used as a matrix material for the phosphorescent compound in the light-emitting layer. The organic electroluminescent device herein may comprise one light-emitting layer, or it may comprise multiple light-emitting layers, wherein at least one light-emitting layer comprises at least one compound according to the invention as a matrix material.

[0096] If the compound according to the invention is used as a matrix material for phosphorescent compounds in the luminescent layer, it is preferably used in combination with one or more phosphorescent materials (triplet emitters). Phosphorescence in the sense of this invention refers to light emitted from excited states having relatively high spin multiplicity (i.e., spin states > 1), particularly from excited triplet states. In the sense of this application, all luminescent complexes containing transition metals or lanthanides, particularly all iridium, platinum, and copper complexes, are considered phosphorescent compounds. In the sense of this application, red and yellow triplet emitters exhibit the lowest triplet T1, which is contained between 2.4 eV and 1.8 eV.

[0097] The energy of the lowest triplet state T1 of the phosphorescent luminescent material was determined via quantum chemical calculations using the software package "Gaussian09, version D.01" (Gaussian). For the organometallic compound calculations, geometry optimization was first performed using the Hartree-Fock method, the standard basis set "LanL2MB" (Gaussian input line "#HF / LanL2MB opt"), and a charge of 0 with multiplicity 1. Subsequently, single-point energy calculations were performed on the optimized geometry. In these calculations, the ground state and triplet state were determined via the TDDFT method (time-dependent density functional theory) with the DFT functional B3PW91 and the standard basis set 6-31G(d) (charge 0, multiplicity 1). The Gaussian input line was "#B3PW91 / gen pseudo=lanl2 td=(50-50,nstates=4)". The ECP basis set "LanL2DZ" was used for the metal atom, compared to all other atoms.

[0098] The lowest energy singlet state is S0. The triplet state T1 is defined as the relative excitation energy (in eV) of the triplet state with the lowest energy, which is derived from the single-point quantum chemical calculations described above.

[0099] The methods described in this paper are independent of the software package used and always produce the same results. Examples of commonly used programs for this purpose are "Gaussian09W" (Gaussian Corporation) and Q-Chem 4.1 (Q-Chem Corporation).

[0100] Based on the entire mixture comprising the luminescent material and the matrix material, the mixture of the compound and the luminescent compound according to the invention comprises between 99 vol% and 1 vol%, preferably between 98 vol% and 10 vol%, particularly preferably between 97 vol% and 60 vol%, and especially between 95 vol% and 80 vol%. Accordingly, based on the entire mixture comprising the luminescent material and the matrix material, the mixture comprises between 1 vol% and 99 vol%, preferably between 2 vol% and 90 vol%, particularly preferably between 3 vol% and 40 vol%, and especially between 5 vol% and 20 vol%.

[0101] Another preferred embodiment of the present invention is the use of the compound according to the invention as a matrix material for phosphorescent emitters in combination with other matrix materials. Particularly suitable matrix materials that can be used in combination with the compounds according to the invention are aromatic ketones, aromatic phosphine oxides or aromatic sulfoxides or sulfones (e.g., according to WO 2004 / 013080, WO 2004 / 093207, WO 2006 / 005627 or WO 2010 / 006680), triarylamines, carbazole derivatives, such as CBP (N,N-biscarbazole biphenyl) or carbazole derivatives disclosed in WO 2005 / 039246, US 2005 / 0069729, JP 2004 / 288381, EP 1205527, WO 2008 / 086851 or WO 2013 / 041176, indolecarbazole derivatives (e.g., according to WO 2007 / 063754 or WO 2008 / 056746), indobenzocarbazole derivatives (e.g., according to WO 2010 / 136109, WO 2011 / 000455, WO 2013 / 041176 or WO 2013 / 056776), azacarbazole derivatives (e.g., according to EP 1617710, EP 1617711, EP 1731584, JP 2005 / 347160), bipolar matrix materials (e.g., according to WO 2007 / 137725), silanes (e.g., according to WO 2005 / 111172), azaboranecyclopentadiene or borate esters (e.g., according to WO 2006 / 117052), triazine derivatives (e.g., according to WO 2007 / 063754, WO 2008 / 056746, WO 2008 / 056746, WO 2008 / 056746), WO 2008 / 056746 ... 2010 / 015306, WO 2011 / 057706, WO 2011 / 060859 or WO 2011 / 060877), zinc complexes (e.g. according to EP 652273 or WO 2009 / 062578), diazasiloxane or tetraazasiloxane derivatives (e.g. according to WO 2010 / 054729), diazaphosphane derivatives (e.g. according to WO 2010 / 054730), bridged carbazole derivatives (e.g. according to WO 2011 / 042107, WO 2011 / 060867, WO 2011 / 088877 and WO 2012 / 143080), or triphenylene derivatives (e.g. according to WO 2012 / 048781). Other phosphorescent emitters (which emit light at shorter wavelengths than the actual emitters) may also exist in the mixture as a common component, or as compounds that do not significantly participate in charge transport (if such compounds exist, as described in, for example, WO 2010 / 108579).The selection of suitable matrix materials and light emitters for the light-emitting layer, as well as the determination of suitable relative proportions of all available materials, are known in the art.

[0102] Suitable phosphorescent compounds (= triplet luminescent materials) are particularly those that emit light under appropriate excitation, preferably in the visible light region, and additionally contain at least one atom with an atomic number greater than 20, preferably greater than 38 and less than 84, particularly preferably greater than 56 and less than 80, especially metals having such atomic numbers. The phosphorescent materials used are preferably compounds containing copper, molybdenum, tungsten, rhenium, ruthenium, osmium, rhodium, iridium, palladium, platinum, silver, gold, or europium, especially compounds containing iridium or platinum.

[0103] Examples of the above-mentioned luminescent materials are disclosed in the following applications: WO 00 / 70655, WO 2001 / 41512, WO 2002 / 02714, WO 2002 / 15645, EP 1191613, EP 1191612, EP 1191614, WO 2005 / 033244, WO 2005 / 019373, US 2005 / 0258742, WO 2010 / 086089, WO 2011 / 157339, WO 2012 / 007086, WO 2012 / 163471, WO 2013 / 000531 and WO 2013 / 020631. Alternatively suitable are, for example, the metal complexes disclosed in applications EP 2872590 and EP2882763. Generally, all phosphorescent complexes known to those skilled in the art for use in phosphorescent OLEDs and as described in the field of organic electroluminescence are suitable, and other phosphorescent complexes will be readily available to those skilled in the art without inventive effort.

[0104] The compounds according to the invention are also particularly suitable as matrix materials for phosphorescent emitters in organic electroluminescent devices, as described, for example, in US 2011 / 0248247 and US 2012 / 0223633. In these multicolor display components, an additional blue emitting layer is applied to all pixels by vapor deposition over the entire area; emitting layers that have a color other than blue can also be applied. Surprisingly, it has been found that the compounds according to the invention, when used as matrix materials for red and / or green pixels, and more particularly for red pixels, continue to produce very excellent luminescence together with the vapor-deposited blue emitting layer.

[0105] In another embodiment of the invention, the organic electroluminescent device according to the invention does not include a separate hole injection layer and / or hole transport layer and / or hole blocking layer and / or electron transport layer; that is, the light-emitting layer is directly adjacent to the hole injection layer or the anode, and / or the light-emitting layer is directly adjacent to the electron transport layer or the electron injection layer or the cathode, as described, for example, in WO2005 / 053051. A metal complex that is the same as or similar to the metal complex in the light-emitting layer can also be used as the hole transport or hole injection material directly adjacent to said light-emitting layer, as described, for example, in WO 2009 / 030981.

[0106] In another embodiment of the invention, the compound according to the invention is used in an exciton blocking layer.

[0107] In another preferred embodiment of the invention, the compound according to the invention is used as an electron transport material in an electron transport or electron injection layer. The luminescent layer here can be fluorescent or phosphorescent. If the compound is used as an electron transport material, it is preferably doped with, for example, an alkali metal or an alkali metal complex such as Li or LiQ (lithium hydroxyquinoline).

[0108] In another preferred embodiment of the invention, the compound according to the invention is used in a hole blocking layer. A hole blocking layer is a layer directly adjacent to the light-emitting layer on the cathode side. Another preferred embodiment uses the compound as part of a charge-generating layer. A charge-generating layer (CGL) acts as an injector of electron-hole pairs when a voltage is applied and is well known in the art. Typically, a CGL consists of an electron-rich layer (e.g., an n-doped electron transport layer) adjacent to an electron-poor layer (e.g., a p-doped hole transport layer). However, in some cases, the CGL may be a single layer. In other cases, one or both layers of the CGL may be doped or undoped.

[0109] In the other layers of the organic electroluminescent device according to the invention, all materials can be used in the manner commonly used in the prior art. Therefore, those skilled in the art can, without inventive effort, combine all known materials for organic electroluminescent devices with compounds according to formula (1) or formula (2) or the preferred embodiments described above.

[0110] Furthermore, a preferred organic electroluminescent device is characterized by coating one or more layers via a sublimation process, wherein the material is sublimated in a vacuum sublimation unit at a temperature of less than 10... -5 millibars, preferably less than 10 -6 An initial pressure of millibars is applied via vapor deposition. However, the initial pressure can also be even lower, for example, less than 10. -7 millibar.

[0111] Also preferred are organic electroluminescent devices characterized by coating one or more layers by an OVPD (organic vapor deposition) method or by means of carrier gas sublimation, wherein in 10 -5 The material is applied under pressures between millibar and 1 bar. A special case of this method is the OVJP (Organic Vapor Jet Printing) method, in which the material is applied directly through the nozzle and is thus structured (e.g., MS Arnold et al., Applied Physics Letters, 2008, 92, 053301).

[0112] Furthermore, a preferred organic electroluminescent device is characterized by producing one or more layers from a solution, for example by spin coating or by any desired printing method (e.g., screen printing, flexographic printing, offset printing, LITI (photoinduced thermal imaging, thermal transfer printing), inkjet printing, or nozzle printing). For this purpose, a soluble compound is required, which is obtained, for example, through appropriate substitution.

[0113] Hybrid methods are also feasible, for example, in which one or more layers are applied from a solution and one or more other layers are applied by vapor deposition. These methods are generally known to those skilled in the art and can be applied by those skilled in the art to organic electroluminescent devices containing the compounds of the present invention without inventive effort.

[0114] The compounds according to the present invention and the organic electroluminescent devices according to the present invention have one or more of the following surprising advantages over the prior art:

[0115] 1. The compounds according to the invention, when used as matrix materials for fluorescent or phosphorescent emitters, result in long lifetimes. This is particularly true when the compounds are used as matrix materials for phosphorescent emitters.

[0116] 2. The compounds according to the invention result in very high efficiency. This is particularly applicable when the compounds are used as a matrix material for phosphorescent emitters or as a hole-blocking material.

[0117] 3. In some embodiments, the compounds according to the invention result in low-voltage devices. This is particularly applicable when the compounds are used as matrix materials for phosphorescent emitters or in electron transport layers.

[0118] These advantages are not accompanied by any damage to other electronic properties.

[0119] The invention is explained in more detail by way of the following examples, but is not intended to limit the invention. Those skilled in the art will be able to practice the invention within the scope disclosed herein using the specification, and will be able to prepare other compounds according to the invention and use them in electronic devices or in the methods of the invention without inventive effort. Example

[0120] A) Synthesis Examples

[0121] Unless otherwise indicated, the following synthesis is carried out in an anhydrous solvent under a protective gas atmosphere. The solvents and reagents are available from ALDRICH or ABCR. The numbers indicated in the case of commercially available starting materials are the corresponding CAS numbers.

[0122] The materials of the present invention can generally be prepared according to scheme 1 or 2 as defined above.

[0123] a) 6-Bromo-2-fluoro-2'-methoxy-biphenyl

[0124]

[0125] 200 g (664 mmol) of 1-bromo-3-fluoro-2-iodobenzene, 101 g (664 mmol) of 2-methoxyphenyl-boric acid, and 137.5 g (997 mmol) of sodium tetraborate were dissolved in 1000 mL of THF and 600 mL of water and degassed. Then, 9.3 g (13.3 mmol) of bis(triphenylphosphine)palladium(II) chloride and 1 g (20 mmol) of hydrazine hydrate were added to the reaction mixture, and the mixture was stirred at 70 °C for 48 hours under an inert atmosphere. The cooled solution, containing toluene, was washed several times with water, dried, and concentrated. The product was washed by silica gel column chromatography with toluene / heptane:ethyl (1:2).

[0126] Yield: 155g (553 mmol), 83% of the theoretical value.

[0127] Similarly, the following compounds were prepared:

[0128]

[0129] b) 6'-Bromo-2'-fluoro-biphenyl-2-ol

[0130]

[0131] 112 g (418 mmol) of 6-bromo-2-chloro-2'-methoxy-biphenyl was dissolved in 2 L of dichloromethane and cooled to 5 °C. Then, 41.01 mL (431 mmol) of boron tribromide was added dropwise over 90 minutes, and the mixture was stirred overnight. The mixture was then slowly mixed with water, the organic phase was washed three times with water, dried over Na₂SO₄, evaporated, and purified by chromatography.

[0132] Yield: 104 g (397 mmol), 98% of the theoretical value.

[0133] Similarly, the following compounds were prepared:

[0134]

[0135] c) 1-Bromo-dibenzofuran

[0136]

[0137] Dissolve 111 g (416 mmol) of 6'-bromo-2'-fluoro-biphenyl-2-ol in 2 L of DMF (maximum 0.003% H2O). The solution was then cooled to 5°C. 20 g (449 mmol) of sodium hydride (60% paraffin oil suspension) was added part-wise to the solution. The mixture was stirred for 20 minutes, then heated to 100°C over a period of 45 minutes. After cooling, the mixture was slowly mixed with 500 ml of ethanol, then evaporated and purified by chromatography.

[0138] Yield: 90g (367 mmol), 88.5% of the theoretical value.

[0139] Similarly, the following compounds were prepared:

[0140]

[0141]

[0142] d) 1-Bromo-8-iodo-dibenzofuran

[0143]

[0144] 20 g (80 mmol) of dibenzofuran-1-boric acid, 2.06 g (40.1 mmol) of iodine, 3.13 g (17.8 mmol) of iodic acid, 80 ml of acetic acid, 5 ml of sulfuric acid, 5 ml of water, and 2 ml of chloroform were stirred at 65 °C for 3 hours. After cooling, the mixture was mixed with water to remove the precipitated solid, and the residue was washed three times with water. The residue was recrystallized from toluene and dichloromethane / heptane.

[0145] The yield was 25.6 g (68 mmol), which is 85% of the theoretical value.

[0146] Similarly, the following compounds were prepared:

[0147]

[0148] e) Dibenzofuran-1-boronic acid

[0149]

[0150] 180 g (728 mmol) of 1-bromo-dibenzofuran was dissolved in 1500 mL of anhydrous THF and cooled to -78 °C. At this temperature, 305 mL (764 mmol / 2.5 M in hexane) of n-butyllithium was added to the mixture over approximately 5 minutes, followed by stirring at -78 °C over 2.5 hours. At this temperature, 151 g (1456 mmol) of trimethyl borate was added to the mixture as quickly as possible, and the reaction mixture was slowly heated to room temperature (approximately 18 hours). The reaction solution was washed with water, and the precipitated solid and organic phase were dried over toluene. The crude product was extracted from toluene / dichloromethane at approximately 40 °C.

[0151] Yield: 146g (690 mmol), 95% of the theoretical value.

[0152] Similarly, the following compounds were prepared:

[0153]

[0154] f) Trifluoromethanesulfonic acid-dibenzofuran-1-yl ester

[0155]

[0156] 40 g (217 mmol) of dibenzofuran-1-ol was suspended in 500 mL of dichloromethane under a protective gas atmosphere. Then, 66.9 g (661 mmol) of triethylamine was added dropwise to the suspension. Following this, a solution of 74.5 g of trifluoromethanesulfonic anhydride in 100 mL of dichloromethane was added dropwise. After stirring at 15 °C for 2.5 hours, the solution was mixed with 100 mL of water, the organic phase was separated, and the solution was filtered through silica gel with toluene and then concentrated to dryness.

[0157] The yield was 60g (191 millimoles), which is 88% of the theoretical value.

[0158] Similarly, prepare the following compounds.

[0159]

[0160]

[0161] g) 1-Trifluoromethanesulfonic acid-8-bromo-dibenzofuran-1-yl ester

[0162]

[0163] 40 g (126 mmol) of dibenzofuran-1-yl trifluoromethanesulfonic acid was suspended in 76 mL (506 mmol) of trifluoromethanesulfonic acid. 52 g (291 mmol) of NBS was gradually added to the suspension and the mixture was stirred in the dark for 2 hours. The reaction mixture was then mixed with water / ice, the solids were separated, and the mixture was washed with ethanol. The residue was recrystallized from toluene.

[0164] The yield was 33g (84 mmol), which corresponds to 66% of the theoretical value.

[0165] In the case of the thiophene derivative of the present invention, elemental bromine is used to replace NBS.

[0166] Similarly, the following compounds were prepared:

[0167]

[0168] h)1-Bromo-8-phenanthroline-9-yl-dibenzofuran

[0169]

[0170] 24.4 g (110.0 mmol) of phenanthrene-9-boric acid, 41 g (110.0 mmol) of 1-bromo-8-iodo-dibenzofuran, and 26 g (210.0 mmol) of sodium carbonate were suspended in 500 mL of ethylene glycol diamine ether and 500 mL of water. First, 913 mg (3.0 mmol) of tri-o-tolylphosphine was added to the mixture, followed by 112 mg (0.5 mmol) of palladium(II) acetate. The reaction mixture was then heated under reflux for 16 hours. After cooling, the organic phase was separated, filtered through silica gel, and concentrated to dryness. The residue was recrystallized from toluene and dichloromethane / heptane.

[0171] The yield was 37g (90 mmol), corresponding to 82% of the theoretical value.

[0172] Similarly, the following compounds were prepared:

[0173]

[0174]

[0175]

[0176]

[0177]

[0178]

[0179] i) 1-Fluoranthracene-3-yl-8-phenanthrene-9-yl-dibenzofuran

[0180]

[0181] 65.9 g (156 mmol) of 1-bromo-8-phenanthroline-9-yl-dibenzofuran, 36.7 g (170 mmol) of fluoranthene-3-boronic acid, and 36 g (340 mmol) of sodium carbonate were suspended in 1000 mL of ethylene glycol diamine ether and 280 mL of water. 1.8 g (1.5 mmol) of tetrakis(triphenylphosphine)palladium(O) was added to the suspension, and the reaction mixture was heated under reflux for 16 h. After cooling, the organic phase was separated, filtered through silica gel, washed three times with 200 mL of water, and then concentrated to dryness. The product was subjected to silica gel column chromatography, washed with toluene / heptane (1:2), and subjected to high vacuum (p = 5 × 10⁻⁶). -7 It was obtained by sublimation at a concentration of 99.9% (mbar).

[0182] The yield was 53g (98 mmol), which corresponds to 63% of the theoretical value.

[0183] Similarly, the following compounds were prepared:

[0184]

[0185]

[0186]

[0187]

[0188]

[0189]

[0190]

[0191]

[0192] j) 8-fluoranthene-3-yl-dibenzofuran-1-yl trifluoromethanesulfonate

[0193]

[0194] 41 g (190 mmol) of 1-trifluoromethanesulfonate-8-bromo-dibenzofuran-1-yl ester, 56.5 g (220 mmol) of fluoranthene-3-boronic acid, and 57 g (410 mmol) of potassium carbonate were suspended in 1000 mL of toluene and 100 mL of water. 1.8 g (1.5 mmol) of tetra(triphenylphosphine)palladium(O) was added, and the reaction mixture was heated under reflux for 16 h. After cooling, the organic phase was separated, filtered through silica gel, washed three times with 200 mL of water, and then concentrated to dryness. The product was subjected to silica gel column chromatography, washed with toluene / heptane (1:2), and subjected to high vacuum (p = 5 × 10⁻⁶). -7 It was obtained by sublimation at a concentration of 99.9% (mbar).

[0195] The yield was 76 g (147 mmol), which corresponds to 78% of the theoretical value.

[0196] Similarly, the following compounds were prepared:

[0197]

[0198]

[0199] k)8-Fluoranthracene-3-yl-1-(4,4,5,5-tetramethyl-[1,3,2]dioxaborone-2-yl)-dibenzofuran

[0200]

[0201] 165 g (320 mmol) of 8-phenanthrene-9-yl-dibenzofuran-1-yl trifluoromethanesulfonate, 120 g (484 mmol) of bis(pinacol)-diborane, and 95 g (968 mmol) of potassium carbonate were dissolved in 3200 mL of THF. 15.8 g (20 mmol) of the Pd(dppf)Cl2 complex in dichloromethane was added to the reaction mixture under an inert gas atmosphere, and the reaction mixture was heated under reflux for 16 h. After cooling, the reaction mixture was mixed with water, and the organic phase was separated. The product was then subjected to silica gel column chromatography, washed with toluene / heptane (2:2), and subjected to high vacuum (p = 5 × 10⁻⁶). -7 It was obtained by sublimation at a concentration of 99.9% (mbar).

[0202] The yield was 88g (179 mmol), which corresponds to 56% of the theoretical value.

[0203] Similarly, the following compounds were prepared:

[0204]

[0205]

[0206] l)8-Fluoranthracene-3-yl-[1,1']bi[dibenzofuranyl]

[0207]

[0208] The compound and the following compounds were prepared by a method similar to method i):

[0209]

[0210]

[0211]

[0212] B) OLED manufacturing

[0213] The following examples V1 to E13 (see Tables 1 and 2) show data for various OLEDs.

[0214] Substrate pretreatment in Examples V1-E13: A glass plate with structured ITO (50 nm, indium tin oxide) was formed as a substrate, on which an OLED substrate was fabricated. Before the OLED material evaporated, the substrate was pre-baked at 250°C for 15 minutes, followed by O2 and subsequent argon plasma treatment.

[0215] OLEDs generally have the following layer structure: substrate / hole transport layer (HTL) / optional intermediate layer (IL) / electron blocking layer (EBL) / emitting layer (EML) / optional hole blocking layer (HBL) / electron transport layer (ETL) / optional electron injection layer (EIL) and finally the cathode. The cathode is formed of an aluminum layer with a thickness of 100 nm. Table 1 shows the specific layer structure. The materials used for OLED manufacturing are presented in Table 3.

[0216] All materials are applied in a vacuum chamber via thermal vapor phase deposition. The luminescent layer here always consists of at least one matrix material (host material) and a luminescent dopant (emitting agent), the dopant being mixed with the one or more matrix materials in a specific volume ratio through co-evaporation. Expressions such as IC1:M1:TEG1 (55%:35%:10%) indicate that material IC1 is present in the layer at a volume ratio of 55%, M1 at 35%, and TEG1 at 10%. Similarly, the electron transport layer may also consist of a mixture of two materials.

[0217] The OLED was characterized using standard methods. For this purpose, the electroluminescence spectrum, current efficiency (CE1000, at 1000 cd / m²) were determined. 2 Luminous efficiency (LE1000, measured in cd / A, at 1000 cd / m²) 2(Measured in lm / W), external quantum efficiency (EQE1000, at 1000 cd / m) 2 (Measured as a percentage below) and voltage (U1000, at 1000 cd / m 2 The values ​​(measured in V) are determined from the current / voltage / luminance characteristic line (IUL characteristic line) under the assumption of Lambert luminescence characteristics. At 1000 cd / m² 2 Electroluminescence (EL) spectra were recorded at the luminescence density, and then CIE 1931 x and y coordinates were calculated from the EL spectra.

[0218] Table 2 summarizes the device data for various OLEDs. Examples V1-V3 are comparative examples based on the prior art. Examples E1-E13 illustrate the data for the OLED of the present invention.

[0219] Several embodiments are described in more detail in the following sections to illustrate the advantages of the OLED of the present invention.

[0220] Application of the compound of this invention as a host material in phosphorescent OLED

[0221] Compared with existing materials, using the compounds of this invention as the host material leads to significant improvements in OLED device data, particularly in luminous efficiency.

[0222] Compared with devices using materials CE1, CE2 and CE3, using the materials i39, i36, i37 and i38 of the present invention as the main materials in phosphorescent red OLEDs resulted in a 10-20% improvement in luminous efficiency (comparison of Examples V1 with E1, V2 with E2, E3 and V3 with V4, respectively).

[0223] Table 1: Layer structure of OLED

[0224]

[0225]

[0226] Table 2: Device Data for OLEDs

[0227]

[0228]

[0229] Table 3: Chemical Structure of OLED Materials

[0230]

[0231]

[0232]

Claims

1. An organic electroluminescent device, the organic electroluminescent device comprising a phosphorescent emitter and a matrix material for the phosphorescent emitter, wherein the matrix material is selected from compounds of formula (1-1-4-c). The following definitions apply to the symbols and tags used: X is O or S; Ar is a group of formula (Ar-1). The dashed lines represent bonds that are bonded to adjacent groups described in formula (1-1-4-c); E is C(R) 0 )2; R 3 Each group, selected identically or differently from H, D, F, CN, is a straight-chain alkyl or alkoxy group having 1 to 10 carbon atoms or a branched or cyclic alkyl or alkoxy group having 3 to 10 carbon atoms, and each of these groups may be represented by one or more R... 4 Group substitution; R 0 Each group, selected identically or differently from H, D, F, CN, is a straight-chain alkyl or alkoxy group having 1 to 10 carbon atoms or a branched or cyclic alkyl or alkoxy group having 3 to 10 carbon atoms, and each of these groups may be represented by one or more R... 4 Group substitution; R 4 Each time it appears, it is selected from H, D, F, CN, either the same or different. u is 0, 1, 2, or 3; t is 1; v can be 0, 1, 2, 3, or 4.

2. The organic electroluminescent device according to claim 1, characterized in that... Ar is selected from groups of formulas (Ar-19) to (Ar-22). Where R 0 Having the same meaning as in claim 1, and wherein the groups of formula (Ar-19) to (Ar-22) can be made of one or more R groups as defined in claim 1. 3 The group is substituted at any free position.

3. The organic electroluminescent device according to claim 1, characterized in that... R 3 Each occurrence thereof is identical or different from H, D, F, CN, a straight-chain alkyl group having 1 to 5 carbon atoms or a branched or cyclic alkyl group having 3 to 5 carbon atoms, each of which may be derived from one or more R... 4 Group substitution.

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