Novel materials for organic electroluminescent devices

Abstract

The present invention relates to novel compounds and organic electroluminescent devices such as OLEDs (organic light emitting diodes) that contain these compounds, for example as electron transport materials and / or matrix materials, optionally combined with another matrix material. The invention also relates to mixtures and formulations that contain these novel compounds.

Description

[0001] New materials for organic electroluminescent devices

[0002] The present invention relates to novel compounds and organic electroluminescent devices such as OLEDs (organic light-emitting diodes) containing these compounds, for example as electron-transport materials and / or matrix materials, optionally in combination with another matrix material. Furthermore, the present invention relates to mixtures and formulations containing these novel compounds.

[0003] The construction of organic electroluminescent devices (e.g., OLEDs - organic light-emitting diodes or OLECs - organic light-emitting electrochemical cells), in which organic semiconductors are used as organic functional materials, is described, for example, in US 4,539,507, US 5,151,629, EP 0676461, and WO 98 / 27136. In addition to fluorescent emitters, organometallic complexes that exhibit phosphorescence are increasingly being used as emitting materials (MA Baldo et al., Appl. Phys. Lett. 1999, 75, 4-6). For quantum mechanical reasons, up to four times the energy and power efficiency is possible using organometallic compounds as phosphorescence emitters. In general, there is still room for improvement, both for OLEDs that exhibit singlet emission and for OLEDs that exhibit triplet emission, particularly with regard to efficiency, operating voltage, and lifetime.

[0004] The properties of organic electroluminescent devices are not only determined by the emitters used. The other materials used, such as host and matrix materials, hole-blocking materials, electron-transport materials, hole-transport materials, and electron- or exciton-blocking materials, are also of particular importance. Improvements to these materials can lead to significant improvements in electroluminescent devices.

[0005] In the prior art, heteroaromatic compounds, in particular, are used as electron-transport materials and as matrix materials for phosphorescent compounds. The term "matrix material" is typically used when referring to a host material for phosphorescent emitters. This use of the term "matrix material" is also used for the present invention. Triazinebenzimidazole derivatives are known as compounds that can be used as electron-transport materials and / or as matrix materials in OLEDs (see KR 2018 / 007329, CN 106946853, CN 110922388, CN 112159361, CN202110215311, WO 2015 / 000549, WO 2016 / 012075, WO 2015 / 000549, WO 2019 / 017734, or WO 2020 / 9679).

[0006] However, there is still room for improvement in these compounds, for example for use as matrix materials, particularly in terms of lifetime, but also in terms of efficiency and operating voltage of the device.

[0007] The object of the present invention is therefore to provide compounds that are suitable for use in an organic electroluminescent device and that, when used in this device, lead to good device properties, as well as to provide the corresponding organic electroluminescent device. In particular, the object of the present invention is to provide compounds that lead to a long lifetime, good efficiency, and low operating voltage. The properties of the matrix materials in particular have a significant influence on the lifetime and efficiency of the organic luminescent device.

[0008] A further object of the present invention can be seen in providing compounds which are suitable for use in a phosphorescent or fluorescent, in particular a phosphorescent, OLED, in particular as a matrix material.

[0009] Surprisingly, it was found that these tasks are solved by a

[0010] Compound according to formula (1): Formula (1) where the symbols and indices used have the following meaning:

[0011] L 1 is selected from the group consisting of a single bond, an aromatic ring system with 6 - 40 ring atoms or a heteroaromatic ring system with 5 - 40 ring atoms, wherein optionally both ring systems are independently partially or fully substituted with D;

[0012] L 2is a single bond or an aromatic ring system with 6 - 40 ring atoms, optionally partially or fully substituted with D;

[0013] L 3 is selected from the group consisting of a single bond, an aromatic ring system with 6 - 40 ring atoms or a heteroaromatic ring system with 5 - 40 ring atoms, wherein optionally both ring systems are independently partially or fully substituted with D;

[0014] Het is a group selected from or

[0015] Het (5);

[0016] * indicates the connection to L 2 ;

[0017] Het 1 is selected from the group consisting of an aromatic ring system with 6 - 40 ring atoms or a heteroaromatic ring system with 5 to 40 ring atoms, wherein, optionally, independently of each other, both ring systems are partially or completely substituted with R 3 are substituted;

[0018] R is selected at each occurrence, the same or different, from the

[0019] A group consisting of H, D, F, CN, a straight-chain alkyl group having 1 to 20 C atoms or an alkenyl or alkynyl group having 2 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, where one or more non-adjacent CH2 groups may be replaced by O or S, and where at least one H atom may be replaced by D, F, or CN, or an aromatic ring system having 6 to 40 ring atoms or a heteroaromatic ring system having 5 to 40 ring atoms, in which at least one H atom may be replaced by D, F, Cl, Br, I or CN, and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; two or more adjacent substituents R may form an aliphatic, aromatic or heteroaromatic ring system with one another;

[0020] R 1is selected the same or differently at each occurrence from the

[0021] A group consisting of H, D, F, CN, a straight-chain alkyl group having 1 to 20 C atoms or an alkenyl or alkynyl group having 2 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, where one or more non-adjacent CH2 groups may be replaced by O or S and where at least one H atom may be replaced by D, F, or CN, or an aromatic ring system having 6 to 40 ring atoms or a heteroaromatic ring system having 5 to 40 ring atoms, in which at least one H atom may be replaced by D, F, Cl, Br, I or CN, and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; two or more adjacent substituents R may form an aliphatic, aromatic or heteroaromatic ring system with one another;

[0022] R 2is selected the same or differently at each occurrence from the

[0023] Group consisting of an aromatic ring system with 6 - 40 ring atoms or a heteroaromatic ring system with 5 to 40 ring atoms, where, optionally, both ring systems independently of each other are partially or completely substituted with R 4 are substituted;

[0024] R 3 is selected the same or differently at each occurrence from the

[0025] A group consisting of H, D, F, CN, a straight-chain alkyl group having 1 to 20 C atoms or an alkenyl or alkynyl group having 2 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, where one or more non-adjacent CH2 groups may be replaced by O or S and where at least one H atom may be replaced by D, F, or CN, or an aromatic ring system having 6 to 40 C atoms or a heteroaromatic ring system having 5 to 40 ring atoms, in which at least one F atom may be replaced by D, F, Cl, Br, I or CN, and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; two or more adjacent substituents R may form an aliphatic, aromatic or heteroaromatic ring system with one another;

[0026] R 4 is selected the same or differently at each occurrence from the

[0027] Group consisting of H, D, F or CN; n is 3 when m is 4 or m is 3 when n is 4 and wherein the following compound is excluded from the invention:

[0028] In this patent application, “D” or “D-atom” stands for deuterium.

[0029] An aryl group within the meaning of this invention contains 6 to 40 ring atoms, preferably C atoms. A heteroaryl group within the meaning of this invention contains 5 to 40 ring atoms, where the ring atoms comprise C atoms and at least one heteroatom, with the proviso that the sum of C atoms and heteroatoms is at least 5. The heteroatoms are preferably selected from N, O and / or S. An aryl group or heteroaryl group is understood to be either a simple aromatic cycle, i.e. phenyl, derived from benzene, or a simple heteroaromatic cycle, for example derived from pyridine, pyrimidine or thiophene, or a fused aryl or heteroaryl group, for example derived from naphthalene, anthracene, phenanthrene, quinoline or isoquinoline.An aryl group with 6 to 30 C atoms is therefore preferably phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylenyl, fluoranthenyl, dibenzoanthracenyl, chrysenyl or perylenyl, whereby the attachment of the aryl group as a substituent is not restricted.

[0030] An aromatic ring system within the meaning of this invention contains 6 to 40 C atoms in the ring system, wherein the ring system also comprises the aryl groups described above.

[0031] A heteroaromatic ring system within the meaning of this invention contains 5 to 40 ring atoms and at least one heteroatom. A preferred heteroaromatic ring system has 9 to 40 ring atoms and at least one heteroatom. The heteroaromatic ring system also includes heteroaryl groups, as described above. The heteroatoms in the heteroaromatic ring system are preferably selected from N, O, and / or S. An aromatic or heteroaromatic ring system within the meaning of this invention is understood to mean a system that does not necessarily contain only aryl or heteroaryl groups, but in which several aryl or heteroaryl groups can also be interrupted by a non-aromatic unit (preferably less than 10% of the atoms other than H), such as a C or O atom or a carbonyl group. For example, systems such as 9,9'-spirobifluorene, 9,9-dialkylfluorene, 9,9-diarylfluorene, diaryl ether, stilbene, etc. are also to be considered as aromatic orHeteroaromatic ring systems are understood within the meaning of this invention, as are systems in which two or more aryl groups are interrupted, for example, by a linear or cyclic alkyl group or by a silyl group. Furthermore, systems in which two or more aryl or heteroaryl groups are directly bonded to one another, such as biphenyl, terphenyl, quaterphenyl, or bipyridine, are also encompassed by the definition of aromatic or heteroaromatic ring systems.

[0032] An aromatic or heteroaromatic ring system with 5 - 40 ring atoms, which can be linked to the aromatic or heteroaromatic ring via any position, is understood to mean, for example, groups derived from benzene, naphthalene, anthracene, benzanthracene, phenanthrene, benzophenanthrene, pyrene, chrysene, perylene, fluoranthene, benzfluoranthene, naphthacene, pentacene, benzopyrene, biphenyl, biphenylene, terphenyl, terphenylene, fluorene, spirobifluorene, dihydrophenanthrene, dihydropyrene, cis- or trans-indenofluorene, cis- or trans-monobenzoindenofluorene, cis- or trans-dibenzoindenofluorene, truxene, isotruxene, spirotruxene, spiroisotruxene, furan, benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene, Isobenzothiophene, dibenzothiophene, pyrrole, indole, isoindole, carbazole, indolocarbazole, indenocarbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline, phenothiazine, phenoxazine,Pyrazol, Indazol, Imidazol, Benzimidazol, Naphthimidazol, Phenanthrimidazol, Pyridimidazol, Pyrazinimidazol, Chinoxalinimidazol, Oxazol, Benzoxazol, Naphthoxazol, Anthroxazol, Phenanthroxazol, Isoxazol, 1,2-Thiazol, 1,3- Thiazol, Benzothiazol, Pyridazin, Benzopyridazin, Pyrimidin, Benzpyrimidin, Chinoxalin,

[0033] 1.5-Diazaanthracen, 2,7-Diazapyren, 2,3-Diazapyren, 1,6-Diazapyren, 1,8-Diazapyren,

[0034] 4.5-Diazapyren, 4,5,9, 10-Tetraazaperylen, Pyrazin, Phenazin, Phenoxazin, Pheno- thiazin, Fluorubin, Naphthyridin, Azacarbazol, Benzocarbolin, Phenanthrolin, 1 ,2,3- Triazol, 1,2,4-Triazol, Benzotriazol, 1,2,3-Oxadiazol, 1 ,2,4-Oxadiazol, 1,2,5-Oxadiazol, 1,3,4-Oxadiazol, 1,2,3-Thiadiazol, 1 ,2,4-Thiadiazol, 1 ,2,5-Thiadiazol, 1,3,4-Thiadiazol, 1.3.5-Triazin, 1 ,2,4-Triazin, 1 , 2, 3-Triazin, Tetrazol, 1 ,2,4,5-Tetrazin, 1 ,2,3,4-Tetrazin,

[0035] 1.2.3.5-Tetrazin, Purin, Pteridin, Indolizin und Benzothiadiazol.

[0036] Weiterhin werden unter einer geradkettigen Alkylgruppe mit 1 bis 20 C-Atomen, einer verzweigten oder cyclischen Alkylgruppe mit 3 bis 20 C-Atomen beispielsweise die Reste Methyl, Ethyl, n-Propyl, i-Propyl, Cyclopropyl, n-Butyl, i-Butyl, s-Butyl, t-Butyl, Cyclobutyl, 2-Methylbutyl, n-Pentyl, s-Pentyl, t-Pentyl, 2-Pentyl, neo-Pentyl, Cyclo- pentyl, n-Hexyl, s-Hexyl, t-Hexyl, 2-Hexyl, 3-Hexyl, neo-Hexyl, Cyclohexyl, 1-Methyl- cyclopentyl, 2-Methylpentyl, n-Heptyl, 2-Heptyl, 3-Heptyl, 4-Heptyl, Cycloheptyl, 1- Methylcyclohexyl, n-Octyl, 2-Ethylhexyl, Cyclooctyl, 1-Bicyclo[2,2,2]octyl, 2-Bicyclo- [2,2,2]octyl, 2-(2,6-Dimethyl)octyl, 3-(3,7-Dimethyl)octyl, Adamantyl, Trifluormethyl, Pentafluorethyl, 2,2,2-Trifluorethyl, 1 ,1-Dimethyl-n-hex-1-yl-, 1 ,1-Dimethyl-n-hept-1-yl-,

[0037] 1.1-Dimethyl-n-oct-1-yl-, 1 ,1-Dimethyl-n-dec-1-yl-, 1 ,1-Dimethyl-n-dodec-1-yl-, 1 ,1- Dimethyl-n-tetradec-1-yl-, 1 ,1-Dimethyl-n-hexadec-1-yl-, 1 ,1-Dimethyl-n-octadec-1-yl-,

[0038] 1.1-Diethyl-n-hex-1-yl-, 1,1-Diethyl-n-hept-1-yl-, 1,1-Diethyl-n-oct-1-yl-, 1,1-Diethyl-n-dec-1-yl-, 1,1-Diethyl-n-dodec-1-yl-, 1,1-Diethyl-n-tetradec-1-yl-, 1, 1 -Diethyln-n-hexadec-1-yl-, 1,1-Diethyl-n-octadec-1-yl-, 1-(n-propyl)-cyclohex-1-yl-, l-(n-butyl)-cyclohex-1-yl-, 1-(n-hexyl)-cyclohex-1-yl-, 1-(n-Octyl)-cyclohex-1-yl- and l-(n-Decyl)-cyclohex-1-yl-. The term "cyclic alkyl group" encompasses a monocyclic, bicyclic, or polycyclic group.

[0039] An alkenyl group with 2 to 20 carbon atoms is understood to mean, for example, ethenyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, or cyclooctadienyl. An alkynyl group with 2 to 20 carbon atoms is understood to mean, for example, ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl, or octynyl.

[0040] A straight-chain alkyl group having 1 - 20 C atoms or a branched alkyl group having 3 to 20 C atoms, in which one or more non-adjacent CH2 groups can be replaced by O or S, and in which at least one H atom can be replaced by D, F or CN, is understood to mean, for example, methoxy, trifluoromethoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, 2-methylbutoxy, thiomethyl, 1-thioethyl, 1-thio-i-propyl, 1-thio-n-propoyl, 1-thio-i-butyl, 1-thio-n-butyl or 1-thio-t-butyl.

[0041] In case an aromatic ring system with 6 to 40 ring atoms or a heteroaromatic ring system with 5 to 40 ring atoms can be substituted with one or more alkyl groups each having 1 to 4 carbon atoms, this alkyl group can be selected from the above-mentioned alkyl groups.

[0042] For the purposes of the present invention, adjacent carbon atoms are carbon atoms that are directly linked to one another. Furthermore, "adjacent radicals" in the definition of radicals means that these radicals are bonded to the same carbon atom or to adjacent carbon atoms. These definitions apply accordingly, among other things, to the terms "adjacent groups" and "adjacent substituents."

[0043] The phrase "two or more residues can form a ring system" refers to the formation of an aliphatic, aromatic, or heteroaromatic ring system. For the purposes of this description, it is understood, among other things, that the two residues are linked by a chemical bond with the formal elimination of two hydrogen atoms. This is illustrated by the following scheme:

[0044] In education

[0045] Furthermore, the above formulation should also be understood to mean that if one of the two residues represents hydrogen, the second residue binds to the position to which the hydrogen atom was bonded, forming a ring. This is illustrated by the following scheme:

[0046] The compounds of formula (1) and their preferred embodiments are described below.

[0047] The compounds according to the invention according to formula (1) can be selected from compounds of the following formula (1a) or formula (1b), preferably from compounds of formula (1a):

[0048] Formula (1b).

[0049] In a further preferred embodiment of the present invention, Het 1selected from the group consisting of an aromatic ring system with 6 - 25 ring atoms or a heteroaromatic ring system with 5 to 24 ring atoms, wherein, optionally, independently of each other, both ring systems are partially or completely substituted with R 3 can be substituted. Het is particularly preferred 1 selected from the group consisting of an aromatic ring system with 6 - 18 ring atoms or a heteroaromatic ring system with 5 to 18 ring atoms, wherein, optionally independently of each other, both ring systems are partially or completely substituted with R 3 can be substituted.

[0050] An aromatic ring system having 6 to 25 ring atoms is preferably selected from ortho-, meta- or para-phenyl, ortho-, meta- or para-biphenyl, ortho-, meta-, para- or branched terphenyl, quaterphenyl, in particular ortho-, meta-, para- or branched quaterphenyl, 1- or 2-naphthyl, anthracenyl, preferably 9-anthracenyl, phenanthrenyl, triphenylenyl, 1-, 2-, 3- or 4-fluorenyl, 1-, 2-, 3- or 4-spirobifluorenyl, fluoranthenyl, benzofluoranthenyl or dibenzoanthracenyl and an aromatic ring system having 6 to 18 ring atoms is preferably selected from the above-mentioned phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthrenyl, triphenylenyl or fluoranthenyl.

[0051] Furthermore, a heteroaromatic ring system having 5 to 24 ring atoms, if it does not represent a linker, is preferably selected from the structures of the following formulas Het (1) to Het (5):

[0052] Het (5), where

[0053] ** the connection to, for example, L 3 means R 1 and R 2 have the meaning given above, or the structures according to the following formulas Het (6) to Het (17): where the dashed line represents the connection to, for example, L 3 or Het 1 represents, and R 5 has the same meaning as R.

[0054] If Het 1 represents a heteroaromatic group having 5 to 24 ring atoms, this group is more preferably selected from structures according to the formulae Het (1) to Het (4) and Het (6) to Het (17); particularly preferably, Het 1a heteroaromatic group having 5 to 18 ring atoms, which is selected from structures according to the formulas Het (6) to Het (17), and very particularly preferably the heteroaromatic group having 5 to 18 ring atoms is selected from structures according to the formulas Het (10) to Het (17). In a further preferred embodiment of the present invention, Het is selected from the group consisting of Het (1) to Het (3) or Het (5): where

[0055] * the connection to L 2 indicates and R 1 and R 2 have the meaning given above.

[0056] More preferably, Het is selected from the group consisting of Het (1), Het (2) or Het (3).

[0057] In yet another preferred embodiment of the present invention, the linker L 1selected from the group consisting of a single bond, an aromatic ring system with 6 to 25 ring atoms, or a heteroaromatic ring system with 5 to 18 ring atoms. It is particularly preferred that L 1 a single bond, an aromatic ring system with 6 to 18 ring atoms or a heteroaromatic ring system with 5 to 18 ring atoms. In the case of a heteroaromatic ring system, this ring system preferably represents a dibenzofuran or dibenzothiophene. These ring systems are optionally partially or fully substituted with D. In yet another preferred embodiment of the present invention, the linker L 2 selected from the group consisting of a single bond or an aromatic ring system having 6 to 25 ring atoms. It is particularly preferred that L 2a single bond or an aromatic ring system with 6 to 18 ring atoms. The ring system is optionally partially or fully substituted with D.

[0058] The Left L 3 is preferably selected from the group consisting of a single bond, an aromatic ring system with 6 to 25 ring atoms, or a heteroaromatic ring system with 5 to 18 ring atoms. It is particularly preferred that L 3 a single bond, an aromatic ring system with 6 to 18 ring atoms, or a heteroaromatic ring system with 5 to 18 ring atoms. In the case of a heteroaromatic ring system, this ring system preferably represents a dibenzofuran or dibenzothiophene. These ring systems are optionally partially or fully substituted with D.

[0059] The substituent R is preferably selected from the group consisting of H, D, F, CN, a straight-chain alkyl group having 1 to 10 C atoms or an alkenyl or alkynyl group having 2 to 10 C atoms or a branched or cyclic alkyl group having 3 to 10 C atoms, where one or more non-adjacent CH2 groups can be replaced by O or S and where at least one H atom can be replaced by D, F, or CN or an aromatic ring system having 6 to 24 ring atoms or heteroaromatic ring system having 5 to 24 ring atoms, in which at least one H atom can be replaced by D, F, Cl, Br, I or CN and which can be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; more preferably, R is selected from the group consisting of H, D, F, CN, a straight-chain alkyl group having 1 to 6 C atoms or an alkenyl or alkynyl group having 2 to 6 C atoms or a branched or cyclic alkyl group having 3 to 8 C atoms,where one or more non-adjacent CH2 groups may be replaced by O or S and where at least one H atom may be replaced by D, F, or CN or an aromatic ring system having 6 to 18 ring atoms or a heteroaromatic ring system having 5 to 18 ring atoms, in which at least one H atom may be replaced by D, F, Cl, Br, I or CN and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms, particularly preferably R is selected from the group consisting of H, D, F, CN, an aromatic ring system having 6 to 12 ring atoms or a heteroaromatic ring system having 5 to 18 ring atoms and very particularly preferably R is selected from the group consisting of H, D, F, CN or an aromatic ring system having 6 to 12 ring atoms. The substituent R, 1is preferably selected from the group consisting of H, D, F, CN, a straight-chain alkyl group having 1 to 10 C atoms or an alkenyl or alkynyl group having 2 to 10 C atoms or a branched or cyclic alkyl group having 3 to 10 C atoms, where one or more non-adjacent CH2 groups may be replaced by O or S and where at least one H atom may be replaced by D, F, or CN or an aromatic ring system having 6 to 24 ring atoms or heteroaromatic ring system having 5 to 18 ring atoms, in which at least one H atom may be replaced by D, F, Cl, Br, I or CN and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; more preferably R 1 selected from the group consisting of H, D, F, CN, an aromatic ring system with 6 to 12 ring atoms or a heteroaromatic ring system with 5 to 18 ring atoms.

[0060] The substituent R 2is preferably selected from the group consisting of an aromatic ring system with 6 - 24 ring atoms or a heteroaromatic ring system with 5 to 18 ring atoms, where, optionally, both ring systems independently of one another are partially or completely substituted with R 4 are substituted. R 2 selected from the group consisting of an aromatic ring system with 6 - 18 ring atoms or a heteroaromatic ring system with 5 to 18 ring atoms. The respective ring systems can independently be partially or completely substituted with R 4 be substituted.

[0061] The substituent R 3is preferably selected from the group consisting of H, D, F, CN, a straight-chain alkyl group having 1 to 10 C atoms or an alkenyl or alkynyl group having 2 to 10 C atoms or a branched or cyclic alkyl group having 3 to 10 C atoms, where one or more non-adjacent CH2 groups may be replaced by O or S and where at least one H atom may be replaced by D, F, or CN or an aromatic ring system having 6 to 24 C atoms or heteroaromatic ring system having 5 to 18 ring atoms, in which at least one H atom may be replaced by D, F, Cl, Br, I or CN and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; two or more adjacent substituents R can form an aliphatic, aromatic or heteroaromatic ring system with one another; R is preferred 3selected from the group consisting of H, D, F, CN, a straight-chain alkyl group having 1 to 6 C atoms, an aromatic ring system having 6 to 12 ring atoms or a heteroaromatic ring system having 5 to 18 ring atoms.

[0062] The substituent R 4 preferably represents H or D.

[0063] Within the scope of the present invention, the above-mentioned preferred embodiments can be combined with one another as desired within the limitations of claim 1.

[0064] The present invention further provides a mixture comprising at least one compound according to formula (1) and at least one further compound selected from the group of matrix materials, phosphorescent emitters, fluorescent emitters and / or emitters exhibiting TADF (thermally activated delayed fluorescence).

[0065] The present invention also further provides a formulation comprising at least one compound of formula (1) or a mixture as described above and at least one solvent.

[0066] Yet another object of the invention is an organic electroluminescent device comprising an anode, a cathode and at least one organic layer containing at least one compound of formula (1).

[0067] The above-mentioned preferred embodiments for the compounds according to formula (1) also apply to the mixture according to the invention, the formulation according to the invention and the organic electroluminescent device according to the invention.

[0068] Examples of compounds according to the invention according to formula (1) are listed in the following Table (1). Table 1:

[0069]

[0070] Particularly suitable compounds of formula (1) are compounds E1 to E27 of the following Table 2:

[0071]

[0072] The compounds of the invention can be prepared using methods known to those skilled in the art, such as the Suzuki coupling. The compounds according to formula (1) of the present invention can be prepared as shown in Scheme 1 below:

[0073] Scheme 1:

[0074] Examples:

[0075] Unless otherwise stated, the following syntheses are carried out under a protective gas atmosphere in dried solvents. The reactants (spray-dried potassium fluoride), tri-tert-butylphosphine, and palladium(II) acetate) are available from ALDRICH. 3-Chloro-5,6-diphenyl-1,2,4-triazine can be prepared analogously to EP 577559. 2',7'-Di-tert-butyl-spiro-9,9'-bifluorene-2,7-bisboronic acid glycol ester can be prepared according to WO 02 / 077060, and 2-chloro-4,6-diphenyl-1,3,5-triazine can be prepared according to US Pat. No. 5,438,138. Spiro-9,9'-bifluorene-2,7-bis(boronic acid glycol ester) can be prepared analogously to WO 02 / 077060. The numbers for the known starting materials, some of which are given in square brackets, are the corresponding CAS numbers. a) 2,4-Dichloro-6-dibenzofuran-2-yl-1,3,5-triazine

[0076] 1.5 g (61 mmol, 1.12 eq) of magnesium turnings are heated in a four-necked flask for a few minutes. Then, a few ml of 14.8 g (60 mmol, 1.10 eq) of 2-bromodibenzofuran in 100 ml of dried THF are added until the Grignard reaction begins. The remaining solution is then added slowly to maintain the Grignard reaction at reflux. After the addition is complete, the mixture is cooled to approximately 0 °C using an ice bath. In a second apparatus, 10.9 g (60 mmol, 1.0 eq) of 2,4,6-trichloro-1,3,5-triazine dissolved in 60 ml of dried THF is cooled using an ice bath. The Grignard reagent is transferred to a dropping funnel and slowly added to this solution. After stirring overnight at room temperature, the mixture was diluted with 100 ml of THF and 50 ml of 1M HCl was added. The resulting precipitate was washed with water, ethanol, and heptane and recrystallized from toluene.

[0077] Yield: 12.7 g (40.4 mmol), 67% of theory, purity according to 1 H-NMR approx. 98%.

[0078] Analogously, the following connections are made:

[0079] b) 2-Chloro-4-dibenzofuran-2-yl-6-triphenylen-2-yl-1,3,5-triazine

[0080] 1.5 g (61 mmol, 1.12 eq) of magnesium turnings are heated in a four-necked flask for a few minutes. Then, 18.6 g (60 mmol, 1.10 eq) of 2-bromotriphenylene in 100 mL of dried THF are added until the Grignard reaction begins. The remaining solution is then added slowly to maintain the Grignard reaction at reflux. After the addition is complete, the mixture is cooled to approximately 0 °C using an ice bath. In a second apparatus, 18.9 g (60 mmol, 1.0 eq) of 2,4-dichloro-6-dibenzofuran-2-yl-1,3,5-triazine dissolved in 60 mL of dried THF is cooled using an ice bath. The Grignard reagent is transferred to a dropping funnel and slowly added to this solution. After stirring overnight at room temperature, the mixture was diluted with 100 ml of THF and 50 ml of 1M HCl was added. The resulting precipitate was washed with water, ethanol, and heptane and recrystallized from toluene.

[0081] Yield: 21 g (42.5 mmol), 70% of theory, purity according to 1 H-NMR approx. 98%.

[0082] Analogously, the following connections are made: c) 2-[3-(4-dibenzofuran-2-yl-6-triphenylen-2-yl-1,3,5-triazin-2-yl)phenyl]-1-phenyl-benzimidazole

[0083] 48.6 g (96 mmol, 1 eq) of 2-chloro-4-dibenzofuran-2-yl-6-triphenylen-2-yl-1,3,5-triazine, 34 g (108 mmol, 1,1 eq) of [3-(1-phenylbenzimidazol-2-yl)phenyl]boronic acid, and 20.4 g (192 mmol, 2.0 eq) of sodium carbonate were dissolved in 400 ml of toluene, 250 ml of water, and 190 ml of ethanol under an inert atmosphere. Then, 1.11 g (0.96 mmol, 0.01 eq) of tetrakis(triphenylphosphine)palladium were added, and the mixture was refluxed overnight at 110 °C. After the reaction was complete, 350 ml of water were added, and the precipitated solid was filtered. The organic layer is separated, washed with water, and dried over sodium sulfate. After evaporation of the solvent, an additional 5.1 g of crude product is obtained. The combined solids are purified by hot extraction from toluene / heptane, recrystallized twice from toluene / heptane, and finally sublimed under high vacuum (p = 5 x 10-5 mbar).

[0084] Yield: 5.3 g (71 mmol), 75% of theory, purity according to 1 H-NMR approx. 97%.

[0085] Analogously, the following connections are made:

[0086]

[0087] d) 1 -(4-Dibenzofuran-1-yl-6-triphenylen-2-yl-1,3,5-triazin-2-yl)-2-phenyl-benzimidazole

[0088] 9.8 g (51 mmol) of 2-phenyl-1H-benzimidazole and 25.3 g (50 mmol) of 2-chloro-4-dibenzofuran-1-yl-6-triphenylen-2-yl-1,3,5-triazine are dissolved in 400 ml of toluene under an argon atmosphere. 1.0 g (5 mmol) of tri-tert-butylphosphine is added and stirred under an argon atmosphere. 0.6 g (2 mmol) of Pd(OAc)2 is added and stirred under an argon atmosphere, followed by 9.5 g (99 mmol) of sodium tert-butoxide. The reaction mixture is stirred under reflux for 24 h. After cooling, the organic phase is separated, washed three times with 200 ml of water, dried over MgSO, filtered, and the solvent is removed in vacuo. The residue is purified by column chromatography on silica gel (eluent: DCM / heptane (1:4)). The residue is recrystallized from toluene and finally sublimed under high vacuum (p = 5 x 10-5 mbar). The purity is 99.9%.

[0089] The yield is 21.9 g (33 mmol), corresponding to 66% of theory. A suitable method for the partial or complete deuteration of a compound according to the invention according to formula (1) by replacing one or more H atoms with D atoms is treatment of the compound to be deuterated in the presence of a platinum or palladium catalyst and a deuterium source. The term "deuterium source" means any compound containing one or more D atoms and capable of releasing them under suitable conditions.

[0090] The platinum catalyst is preferably dry platinum on carbon, preferably 5% dry platinum on carbon. The palladium catalyst is preferably dry palladium on carbon, preferably 5% dry palladium on carbon. A suitable deuterium source is D2O, benzene-d6, chloroform-d, acetonitrile-d3, acetone-d6, acetic acid^, methanol-d4, or toluene-d8. A preferred deuterium source is D2O or a combination of D2O and a fully deuterated organic solvent. A particularly preferred deuterium source is the combination of D2O with a fully deuterated organic solvent, whereby the fully deuterated solvent is not limited here. Particularly suitable fully deuterated solvents are benzene-d6 and toluene-d8. A particularly preferred deuterium source is a combination of D2O and toluene-d8.The reaction is preferably carried out with heating, more preferably with heating to temperatures between 100 °C and 200 °C. Furthermore, the reaction is preferably carried out under pressure.

[0091] By the processes listed above, optionally followed by purification such as recrystallization or sublimation, the compounds of formula (1) can be obtained in high purity, preferably at least 98% purity (determined by 1 H-NMR and / or HPLC).

[0092] For processing the compounds of the invention from the liquid phase, for example by spin coating or printing processes, formulations of the compounds of the invention or mixtures of compounds of the invention with other functional materials, such as matrix materials, fluorescent emitters, phosphorescent emitters, and / or emitters exhibiting TADF, are required. These formulations can be, for example, solutions, dispersions, or emulsions. It may be preferred to use mixtures of two or more solvents for this purpose. Suitable and preferred solvents are, for example, toluene, anisole, o-, m- or p-xylene, methyl benzoate, mesitylene, tetralin, veratrole, THF, methyl-THF, THP, chlorobenzene, dioxane, phenoxytoluene, in particular 3-phenoxytoluene, (-)-fenchone, 1,2,3,5-tetramethylbenzene, 1,2,4,5-tetramethylbenzene, 1-methylnaphthalene, 2-methylbenzothiazole, 2-phenoxyethanol, 2-pyrrolidinone, 3-methylanisole, 4-methylanisole, 3,4-Dimethylanisol, 3,5-Dimethylanisol, Acetophenon, a-Terpineol, Benzothiazol, Butylbenzoat, Cumol, Cyclohexanol, Cyclohexanon, Cyclohexylbenzol, Decalin, Dodecylbenzol, Ethylbenzoat, Indan, NMP, p-Cymol, Phenetol, 1,4-Di- isopropylbenzol, Dibenzylether, Diethylenglycolbutylmethylether, Triethylenglycolbutyl- methylether, Diethylenglycoldibutylether, Triethylenglycoldimethylether, Diethylen- glycolmonobutylether, T ripropyleneglycoldimethylether, T etraethylenglycoldimethyl- ether, 2-lsopropylnaphthalin, Pentylbenzol, Hexylbenzol, Heptylbenzol, Octylbenzol, 1,1-Bis(3,4-dimethylphenyl)ethan, 2-Methylbiphenyl, 3-Methylbiphenyl, 1-Methyl- naphthalin, 1-Ethylnaphthalin, Ethyloctanoat, Sebacinsäure-diethylester, Octyloctanoat, Heptylbenzol, Menthyl-isovalerat, Cyclohexylhexanoat oder Mischungen dieser Lösemittel.,

[0093] The above compounds according to the invention according to formula (1), preferably of formula (1a) or compounds E1 to E27, are suitable for use in an organic electroluminescent device (synonymously an organic electroluminescent device), preferably an organic light-emitting transistor (OLET), an organic field quench device (OFQD), an organic light-emitting electrochemical cell (OLEC, LEC, LEEC), an organic laser diode (O-laser), or an organic light-emitting diode (OLED). The organic electroluminescent device according to the invention is in particular an organic light-emitting diode or an organic light-emitting electrochemical cell. The device according to the invention is particularly preferably an OLED.

[0094] The organic layer of the device according to the invention preferably contains, in addition to a light-emitting layer (EML), a hole-injection layer (HIL), a hole-transport layer (HTL), a hole-blocking layer (HBL), an electron-transport layer (ETL), an electron-injection layer (EIL), an exciton-blocking layer, an electron-blocking layer, and / or charge-generation layers. The device according to the invention may also contain several layers from this group, preferably selected from EML, HIL, HTL, ETL, EIL, and HBL. Interlayers, which, for example, have an exciton-blocking function, may also be introduced between two emitting layers. If several emission layers are present, they preferably have a total of several emission maxima between 380 nm and 750 nm, so that overall white emission results, i.e.Various emitting compounds that can fluoresce or phosphoresce are used in the emitting layers. Systems with three emitting layers are particularly preferred, with the three layers exhibiting blue, green, and orange or red emission. Alternatively to this combination, an emitting layer can also exhibit yellow emission. Such combinations are known to the person skilled in the art. The organic electroluminescent device according to the invention can also be a tandem electroluminescent device, in particular for white-emitting OLEDs. The device can also contain inorganic materials or layers composed entirely of inorganic materials.

[0095] It is not difficult for a person skilled in the art to draw on a multitude of materials known in the prior art to select suitable materials for use in the layers of the organic electroluminescent device described above. In doing so, the person skilled in the art will consider common considerations regarding the chemical and physical properties of the materials, as they are aware that the materials in an organic electroluminescent device are interrelated. This applies, for example, to the energy positions of the orbitals (HOMO, LIIMO) or the position of triplet and singlet energies, as well as other material properties.

[0096] The compound of formula (1) according to the invention, as described above or preferably described or as listed in Table 1 or Table 2, can be used in different layers, depending on the precise structure. Preference is given to an organic electroluminescent device comprising a compound according to formula (1) or the preferred embodiments outlined above in at least one light-emitting layer as matrix material (synonym for host material) for fluorescent emitters, phosphorescent emitters, or for emitters exhibiting TADF (thermally activated delayed fluorescence), in particular for phosphorescent emitters. Furthermore, the compound of the invention can also be used in at least one electron-transport layer and / or in at least one hole-transport layer and / or in at least one exciton-blocking layer and / or in at least one hole-blocking layer.The compound according to the invention is particularly preferably used as a matrix material in at least one light-emitting layer or as an electron transport or hole blocking material in an electron transport or hole blocking layer.

[0097] According to a preferred embodiment of the present invention, the compounds according to the invention of the formula (1), preferably of the formula (1a) or compounds which are listed in Table 1 or Table 2, can be used as matrix material in the at least one light-emitting layer, wherein this layer contains at least one further matrix material (so-called mixed matrix systems). Suitable matrix materials which can be used in combination with the compounds according to the invention are aromatic ketones, aromatic phosphine oxides or aromatic sulfoxides or sulfones, triarylamines, carbazole derivatives, biscarbazoles, indolocarbazole derivatives, indenocarbazole derivatives, azacarbazole derivatives, bipolar matrix materials, azaboroles or boronic esters, triazine derivatives, zinc complexes, diazasilole or tetraazasilole derivatives, diazaphosphole derivatives, bridged carbazole derivatives, triphenylene derivatives or dibenzofuran derivatives.Likewise, another phosphorescent emitter, which emits at a shorter wavelength than the actual emitter, can be present in the mixture as a co-host, or a compound that does not participate, or does not participate to a significant extent, in the charge transport, such as a wide band-gap compound.

[0098] A wide-band-gap material is understood herein to mean a material within the meaning of the disclosure of US 7,294,849, which is characterized by a band gap of at least 3.5 eV, where the band gap is understood to be the distance between the HOMO and LUMO energy of a material.

[0099] Particularly suitable further matrix materials which can be advantageously combined with compounds of formula (1) as previously described or preferably described in a system can be selected from the compounds of formulas (2) to (12) as described below.

[0100] A further subject of the invention is accordingly an organic electroluminescent device comprising an anode, a cathode and at least one organic layer containing at least one light-emitting layer, wherein the at least one light-emitting layer contains at least one compound of the formula (1) as matrix material 1, as described above or described as preferred, and at least one compound of the formulas (2) to (12) as matrix material 2,

[0101] Formula (5) where the symbols and indices used are: A 1 is C(R 7 )2, NR 7 , O or S; A is at each occurrence independently a group of the formula

[0102] (6) or (7),

[0103] 10 Formula (9),

[0104] X2 is the same or different at each occurrence CH, CR 6 or N, where a maximum of 2 symbols X2 can mean N;

[0105] * indicates the binding site to formula (5);

[0106] R 6 is, identically or differently at each occurrence, D, CN, a straight-chain alkyl group having 1 to 20 C atoms or an alkenyl or alkynyl group having 2 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, where the alkyl, alkenyl or alkynyl group is each substituted by one or more radicals R 7 may be substituted and wherein one or more non-adjacent CH2 groups are substituted by Si(R 7 )2, C=O, NR 7 , O, S or CONR 7 may be replaced, or an aromatic or heteroaromatic ring system with 5 to 60 ring atoms, each of which is substituted by one or more radicals R 7 can be substituted; two radicals R 6 also form an aromatic, heteroaromatic, aliphatic or heteroaliphatic ring system with each other;

[0107] Ar is, at each occurrence, identically or differently, an aromatic or heteroaromatic ring system with 5 to 40 ring atoms, which is substituted with one or more radicals R 7 can be substituted; Ar 1 represents, identically or differently on each occurrence, an aromatic or heteroaromatic ring system having 5 to 40 ring atoms, which is substituted by one or more radicals R 7 can be substituted;

[0108] R 7 is the same or different at each occurrence D, F, CI, Br, I, N(R 8 )2, CN, NO2, OR 8 , SR 8 , Si(R 8 )3, B(OR 8 )2, C(=O)R 8 , P(=O)(R 8 )2, S(=O)R 8 , S(=O)2R 8 , OSO2R 8, a straight-chain alkyl group having 1 to 20 C atoms or an alkenyl or alkynyl group having 2 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, wherein the alkyl, alkenyl or alkynyl group is each substituted by one or more radicals R 8 may be substituted, with one or more non-adjacent CH2 groups being substituted by Si(R 8 )2, C=O, NR 8 , O, S or CONR 8 may be replaced, or an aromatic or heteroaromatic ring system with 5 to 40 ring atoms, each of which is substituted by one or more radicals R 8 may be substituted; two or more radicals R 7 together form an aromatic, heteroaromatic, aliphatic or heteroaliphatic ring system, preferably the radicals R 7 no such ring system;

[0109] R 8is, identically or differently at each occurrence, H, D, F or an aliphatic, aromatic or heteroaromatic organic radical, in particular a hydrocarbon radical, having 1 to 20 C atoms, in which one or more H atoms may be replaced by F; c, c1, c2 each independently at each occurrence denote 0 or

[0110] 1 , where the sum of the indices c+c1+c2 is 1 at each occurrence; d, d1 , d2 each independently represent 0 or

[0111] 1 , where the sum of the indices at each occurrence d + d1 + d2 is 1; q, q1 , q2 each independently at each occurrence is 0 or 1; s is the same or different at each occurrence: 0, 1, 2, 3 or 4; t is the same or different at each occurrence: 0, 1, 2, or 3; u is the same or different at each occurrence: 0, 1 or 2; and v is 0 or 1.

[0112] In compounds of formulas (2), (3), (4) and (8) to (12), s is preferably 0 or 1 when the radical R 6 is different from D, particularly preferably 0.

[0113] In compounds of formulas (2), (3) or (4), t is preferably 0 or 1 when the radical R 6 is different from D, particularly preferably 0.

[0114] In compounds of formulas (2), (3), (4) and (8) to (12) u is preferably 0 or 1 when the radical R 6 is different from D, particularly preferably 0. The sum of the indices s, t and u in compounds of the formulas (2), (3), (4) and (8) to (12) is preferably at most 6, particularly preferably at most 4 and particularly preferably at most 2. This preferably applies when R 6 is different from D.

[0115] In compounds of formula (5), c, c1, c2 each independently represent 0 or 1 at each occurrence, where the sum of the indices c+c1+c2 represents 1 at each occurrence. Preferably, c2 represents 1.

[0116] In a preferred embodiment of the present invention, compounds of formulas (2) to (5) and (8) to (12) can be combined with the compounds of formula (1) according to the invention, where R 6 identically or differently on each occurrence selected from the group consisting of D, F, CN, a straight-chain alkyl group having 1 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, where the alkyl group is in each case substituted with one or more radicals R 7 may be substituted, or an aromatic or heteroaromatic ring system having 5 to 60 ring atoms, preferably having 5 to 40 ring atoms, each substituted by one or more radicals R 7 can be substituted.

[0117] In a further preferred embodiment of the present invention, compounds of formulas (2) to (5) and (8) to (12) can be combined with the compounds of formula (1) according to the invention, where R 6 identically or differently on each occurrence selected from the group consisting of D or an aromatic or heteroaromatic ring system having 6 to 30 ring atoms, which is reacted with one or more radicals R 7 can be substituted.

[0118] Ar is preferred 1in compounds of formulas (2), (3), (4) and (8) to (12) selected from phenyl, biphenyl, in particular ortho-, meta- or para-biphenyl, terphenyl, in particular ortho-, meta-, para- or branched terphenyl, quaterphenyl, in particular ortho-, meta-, para- or branched quaterphenyl, fluorenyl, which may be linked via the 1-, 2-, 3- or 4-position, spirobifluorenyl, which may be linked via the 1-, 2-, 3- or 4-position, naphthyl, in particular 1- or 2-linked naphthyl, or residues derived from indole, benzofuran, benzothiophene, carbazole, which may be linked via the 1-, 2-, 3- or 4-position, dibenzofuran, which may be linked via the 1-, 2-, 3- or 4-position, dibenzothiophene, which may be linked via which may be linked at the 1-, 2-, 3- or 4-position, indenocarbazole, indolocarbazole, pyridine, pyrimidine, pyrazine, pyridazine, triazine, quinoline, isoquinoline, quinazoline, quinoxaline, phenanthrene or triphenylene,which are each substituted with one or more radicals R, 7 can be substituted. Preferably, An is unsubstituted.

[0119] If A 1 in formula (3) or (4) for NR 7 the substituent R 7 which is bonded to the nitrogen atom, preferably represents an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms, which can also be substituted by one or more radicals R 8 In a particularly preferred embodiment, this substituent R 7 identical or different on each occurrence, represents an aromatic or heteroaromatic ring system having 6 to 24 aromatic ring atoms, in particular having 6 to 18 aromatic ring atoms. Preferred embodiments for R 7 are phenyl, biphenyl, terphenyl and quaterphenyl, which are preferably unsubstituted, as well as radicals derived from triazine, pyrimidine and quinazoline, which are substituted by one or more radicals R 8can be substituted.

[0120] If A 1 in formula (3) or (4) for C(R 7 )2, the substituents R 7 which are bonded to this carbon atom, preferably identically or differently on each occurrence, represent a linear alkyl group having 1 to 10 C atoms or a branched or cyclic alkyl group having 3 to 10 C atoms or an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms, which can also be substituted by one or more radicals R 8 R is particularly preferably 7 represents a methyl group or a phenyl group. The radicals R 7 also form a ring system with each other, which leads to a spiro system.

[0121] In a preferred embodiment of the compounds of formulas (2) to (5) and (8) to (12), these compounds are partially or completely deuterated, particularly preferably completely deuterated.

[0122] The preparation of the compounds of formulas ((2) to (5) and (8) to (12) are generally known and some of the compounds are commercially available.

[0123] Compounds of formula (5) are disclosed, for example, in WO2021 / 180614, pages 110 to 119, in particular as examples on pages 120 to 127. Their preparation is disclosed in WO2021 / 180614 on page 128 and in the synthesis examples on pages 214 to 218.

[0124] If the additional matrix material is a deuterated compound, it is possible that the additional matrix material is a mixture of deuterated compounds with the same basic chemical structure, which differ only in the degree of deuteration.

[0125] In a preferred embodiment of the further matrix material, this is a mixture of deuterated compounds of the formulas (2) to (5) and (8) to (12), as described above, wherein the degree of deuteration of these compounds is at least 50% to 90%, preferably 70% to 100%. Corresponding deuteration methods are known to the person skilled in the art and are described, for example, in KR2016041014, WO2017 / 122988, KR202005282, KR101978651, and WO2018 / 110887 or in Bulletin of the Chemical Society of Japan, 2021, 94(2), 600-605, or Asian Journal of Organic Chemistry, 2017, 6(8), 1063-1071.

[0126] A suitable method for deuterating a compound by exchanging one or more hydrogen atoms for diatoms is to treat the compound to be deuterated in the presence of a platinum or palladium catalyst and a deuterium source. The term "deuterium source" refers to any compound containing one or more diatoms and capable of releasing them under suitable conditions.

[0127] The platinum catalyst is preferably dry platinum on carbon, preferably 5% dry platinum on carbon. The palladium catalyst is preferably dry palladium on carbon, preferably 5% dry palladium on carbon. A suitable deuterium source is D2O, benzene-d6, chloroform-d, acetonitrile-d3, acetone-d6, acetic acid-d4, methanol-d4, or toluene-d8. A preferred deuterium source is D2O or a combination of D2O and a fully deuterated organic solvent. A particularly preferred deuterium source is the combination of D2O with a fully deuterated organic solvent, whereby the fully deuterated solvent is not limited here. Particularly suitable fully deuterated solvents are benzene-d6 and toluene-d8. A particularly preferred deuterium source is a combination of D2O and toluene-d8.The reaction is preferably carried out with heating, more preferably with heating to temperatures between 100 °C and 200 °C. Furthermore, the reaction is preferably carried out under pressure.

[0128] Examples of suitable further matrix materials for a combination with compounds of formula (1), as previously described or preferably described, are the compounds described in WO2019 / 229011, Table 3, pages 137 to 203, which may also be partially or fully deuterated, or compounds described in WO2021 / 180625, Table 3, pages 131 to 127 and in Table 4, pages 137 to 139, or KR20230034896 A, on pages 42 to 47, compounds [2-1] to [2-110], or on pages 49 to 51, compounds [3-1] to [3-26], which may also be partially or fully deuterated.

[0129] Further examples of suitable host materials for combination with compounds of formula (1) or preferred compounds of formula (1a), as previously described or preferably described, are those mentioned below

[0130] Structures of Table 3 and Table 4.

[0131] Table 3:

[0132]

[0133] Particularly suitable host materials which are selected according to the invention and are preferably used in combination with at least one compound of formula (1) or preferred compounds of formula (1a) in the electroluminescent device according to the invention are the compounds of Table 4.

[0134] Table 4:

[0135]

[0136] The above-mentioned host materials of formula (1) and their preferred embodiments or the compounds of Table 1 and the compounds E1 to E27 can be combined as desired in the device according to the invention with the aforementioned matrix materials / host materials, the matrix materials / host materials of formulas (2) to (5) and (8) to (12) and their preferred embodiments of Table 3 or the compounds H1 to H30. Very particularly preferred mixtures of the compounds of formula (1) with the host materials of formulas (2) to (5) and (8) to (12) for the device according to the invention are obtained by combining the compounds E1 to E27 with the compounds H1 to H27 as shown below in Table 5. The first mixture M1, for example, is a combination of the compound E1 with H1.

[0137] Table 5:

[0138] The concentration of the host material of formula (1), as described above or preferably described, in the mixture according to the invention or in the light-emitting layer of the device according to the invention is usually in the range from 5 wt.% to 90 wt.%, preferably in the range from 10 wt.% to 85 wt.%, more preferably in the range from 20 wt.% to 85 wt.%, even more preferably in the range from 30 wt.% to 80 wt.%, very particularly preferably in the range from 20 wt.% to 60 wt.% and most preferably in the range from 30 wt.% to 50 wt.%, based on the total mixture or based on the total composition of the light-emitting layer.

[0139] The concentration of the sum of all host materials of the formulas (2) to (5) and (8) to (12) as described above or described as preferred in the mixture according to the invention or in the light-emitting layer of the device according to the invention is usually in the range from 10 wt.% to 95 wt.%, preferably in the range from 15 wt.% to 90 wt.%, more preferably in the range from 15 wt.% to 80 wt.%, even more preferably in the range from 20 wt.% to 70 wt.%, very particularly preferably in the range from 40 wt.% to 80 wt.% and most preferably in the range from 50 wt.% to 70 wt.%, based on the total mixture or based on the total composition of the light-emitting layer.

[0140] The present invention also relates to a mixture which, in addition to the above-mentioned host materials of formula (1), hereinafter referred to as host material 1, and the host material of at least one of formulas (2) to (5) and (8) to (12), hereinafter referred to as host material 2, as described above or preferably described, contains at least one phosphorescent emitter.

[0141] The present invention also relates to a mixture selected from M1 to M729, which contains at least one phosphorescent emitter.

[0142] A further subject of the invention is therefore an organic electroluminescent device comprising an anode, a cathode and at least one organic layer containing at least one light-emitting layer, wherein the at least one light-emitting layer contains at least one compound of formula (1) as matrix material 1, as described above or described as preferred, and at least one compound of formula (13)

[0143] Formula (13), where the symbols and indices used are:

[0144] W is O, S, C(R 9 )2, N-Ar 2 ;

[0145] R 9 is each independently a straight-chain or branched

[0146] Alkyl group with 1 to 4 C atoms, which may be partially or fully deuterated, or an unsubstituted or partially or fully deuterated aromatic ring system with 6 to 18 C atoms, where two substituents R9 with the C atom to which they are bonded, can form a mono- or polycyclic, aliphatic or aromatic or heteroaromatic unsubstituted, partially deuterated or fully deuterated ring system which can be substituted by one or more substituents R 12 can be substituted;

[0147] Ar 2 is at each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 30 ring atoms, which is substituted by one or more radicals R 12 can be substituted; two residues Ar 2 which bind to the same N-atom, P-atom or B-atom, also by a single bond or a bridge, selected from C(R 12 )2, O or S, may be bridged together;

[0148] R 10 is selected at each occurrence, identically or differently, from the group consisting of F, CI, Br, I, CN, NO2, C(=O)R', P(=O)(AH)2, P(Ar 2 )2, B(Ar 2)2, Si(Ari)s, Si(R')s, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 20 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms or an alkenyl group having 2 to 20 C atoms, each of which may be substituted by one or more radicals R', where one or more non-adjacent CH2 groups may be replaced by R'C=CR', Si(R')2, C=O, C=S, C=NR', P(=O)(R'), SO, SO2, NR', O, S or CONR' and where one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO2;

[0149] R' is selected at each occurrence, identically or differently, from the group consisting of D, F, CI, Br, I, CN, NO2, N(AH)2, NH2, N(R") 2IC(=O)AH, C(=O)H, C(=O)R“, P(=O)(Ari)2, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms or an alkenyl or alkynyl group having 2 to 40 C atoms, each of which may be substituted by one or more radicals R“, where one or more non-adjacent CH2 groups may be replaced by HC=CH, R“C=CR“, C=C, Si(R')2, Ge(R")2, Sn(R")2, C=O, C=S, C=Se, C=NR“, P(=O)(R"), SO, SO2, NH, NR“, O, S, CONH or CONR“, and where one or more H atoms may be replaced by F, CI, Br, I, CN or NO2, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, each of which may be substituted by one or more radicals R", an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R", or a combination of these systems,where optionally two or more adjacent substituents R' may form a monocyclic or polycyclic, aliphatic, aromatic or heteroaromatic ring system which may be substituted by one or more radicals R";,

[0150] R" is, at each occurrence, identically or differently selected from the group consisting of D, F, CN, an aliphatic hydrocarbon radical having 1 to 20 C atoms or an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, in which one or more H atoms may be replaced by D, F, CI, Br, I or CN and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; two or more adjacent substituents R 3form a mono- or polycyclic, aliphatic ring system; it came from these definitions - however, I find it too broad. I will use the following definition for my foreign version - thanks for finding the error

[0151] R' is, at each occurrence, identically or differently, an aliphatic, aromatic or heteroaromatic organic radical, in particular a hydrocarbon radical, having 1 to 20 C atoms, in which one or more H atoms may be replaced by F;

[0152] R 11 is selected at each occurrence, identically or differently, from the group consisting of F, CI, Br, I, CN, NO2, N(Ar 2 )2, NH2, N(R 12 )2, C(=O)Ar 2 , C(=O)H, C(=O)R 12 , P(=O)(Ar 2)2, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms or an alkenyl or alkynyl group having 2 to 40 C atoms, each of which is substituted by one or more radicals R 12 may be substituted, where one or more non-adjacent CH2 groups are substituted by HC=CH, R 12 C=CR 12 , C=C, Si(R 12 )2, Ge(R 12 )2, Sn(R 12 )2, C=O, C=S, C=Se, C=NR 12 , P(=O)(R 12 ), SO, SO2, NH, NR 12 , O, S, CONH or CONR 12 and wherein one or more H atoms may be replaced by D, F, CI, Br, I, CN or NO2, an aromatic or heteroaromatic ring system having 5 to 60 ring atoms, each of which is substituted by one or more radicals R 12 may be substituted, an aryloxy or heteroaryloxy group having 5 to 60 ring atoms, which may be substituted with one or more radicals R 12may be substituted, or a combination of these systems, optionally two or more adjacent substituents R 11 can form a monocyclic or polycyclic, aliphatic, aromatic or heteroaromatic ring system which can be substituted with one or more radicals R 12 can be substituted;

[0153] R 12is selected, identically or differently at each occurrence, from the group consisting of D, F, CN, a straight-chain alkyl group having 1 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, where one or more non-adjacent CH2 groups may be replaced by O or S and where one or more H atoms may be replaced by D, F, or CN or an aromatic or heteroaromatic ring system having 5 to 30 ring atoms, in which one or more H atoms may be replaced by D, F, Cl, Br, I or CN and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; two or more adjacent substituents R 12together form a mono- or polycyclic, aliphatic ring system; x, x1 are each independently 0, 1, 2, 3 or 4; y, z are each independently 0, 1 or 2; a1, a2 are each independently 0, 1, 2, 3, 4 or 5; a3 is 0, 1, 2 or 3; a4 is 0, 1, 2, 3 or 4.

[0154] Compounds of formula (13) are disclosed, for example, in WO2021180614, pages 110 to 119, in particular as examples on pages 120 to 127. Their preparation is disclosed in WO2021180614 on page 128 and in the synthesis examples on pages 214 to 218.

[0155] When the compounds according to the invention according to formula (1) or the preferred embodiments are used as matrix material alone or in a mixed-matrix system for an emitting compound in a light-emitting layer, they are preferably used in combination with one or more phosphorescent materials (triplet emitters). The term phosphorescent emitters typically encompasses compounds in which light emission occurs through a spin-forbidden transition from an excited state with higher spin multiplicity, i.e., a spin state > 1, for example, through a transition from a triplet state or a state with an even higher spin quantum number, for example, a quintet state. Preferably, this refers to a transition from a triplet state.

[0156] Particularly suitable phosphorescent emitters (= triplet emitters) are compounds that emit light upon suitable excitation, preferably in the visible range, and also 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, in particular a metal with this atomic number. Preferably, compounds containing copper, molybdenum, tungsten, rhenium, ruthenium, osmium, rhodium, iridium, palladium, platinum, silver, gold, or europium are used as phosphorescent emitters, in particular compounds containing iridium or platinum. For the purposes of the present invention, all luminescent compounds containing the above-mentioned metals are considered phosphorescent emitters.

[0157] In general, all phosphorescent complexes as used in the prior art for phosphorescent OLEDs and as known to the person skilled in the art in the field of organic electroluminescent devices are suitable.

[0158] A further subject matter of the invention is accordingly an organic electroluminescent device as described above or preferably described, characterized in that the light-emitting layer contains, in addition to the host materials 1 and 2, at least one phosphorescent emitter.

[0159] Preferred examples of phosphorescent emitters are described in WO2019007867 on pages 120 to 126 in Table 5 and on pages 127 to 129 in Table 6. The emitters are incorporated into the description by this reference.

[0160] Particularly preferred examples of phosphorescent emitters are listed in Table 6 below.

[0161] Table 6:

[0162]

[0163] The light-emitting layer in the organic electroluminescent device according to the invention containing at least one phosphorescent emitter is preferably an infrared-emitting, yellow, orange, red, green, blue or ultraviolet-emitting layer, particularly preferably a yellow or green-emitting layer and very particularly preferably a green-emitting layer.

[0164] A yellow-emitting layer is understood to be a layer whose photoluminescence maximum lies in the range from 540 to 570 nm. An orange-emitting layer is understood to be a layer whose photoluminescence maximum lies in the range from 570 to 600 nm. A red-emitting layer is understood to be a layer whose photoluminescence maximum lies in the range from 600 to 750 nm. A green-emitting layer is understood to be a layer whose photoluminescence maximum lies in the range from 490 to 540 nm. A blue-emitting layer is understood to be a layer whose photoluminescence maximum lies in the range from 440 to 490 nm.The photoluminescence maximum of the layer is determined by measuring the photoluminescence spectrum of the layer with a layer thickness of 50 nm at room temperature, wherein the layer contains the inventive combination of the host material 1 of formula (1), in particular formula (1a), and the host material 2, consisting of at least one of (2) to (5) and (8) to (13) and the corresponding emitter.

[0165] The photoluminescence spectrum of the layer is recorded, for example, using a commercially available photoluminescence spectrometer.

[0166] The photoluminescence spectrum of the selected emitter is usually measured in oxygen-free solution, 10' 5molar, measured at room temperature, and any solvent in which the selected emitter dissolves at the specified concentration is suitable. Particularly suitable solvents are usually toluene or 2-methyl-THF, but also dichloromethane. The measurement is carried out using a commercially available photoluminescence spectrometer. The triplet energy T1 in eV is determined from the photoluminescence spectra of the emitters. First, the peak maximum Plmax. (in nm) of the photoluminescence spectrum is determined. The peak maximum Plmax. (in nm) is then converted to eV according to: E(T1 in eV) = 1240 / E(T1 in nm) = 1240 / PLmax. (in nm).

[0167] Preferred phosphorescent emitters are therefore yellow emitters, preferably from Table 6, whose triplet energy T is preferably between ~2.3 eV and ~2.1 eV.

[0168] Preferred phosphorescent emitters are therefore green emitters, preferably from Table 6, whose triplet energy T 1 is preferably between ~2.5 eV and ~2.3 eV.

[0169] Green emitters, preferably from Table 6, as described above, are very particularly preferably selected for the mixture according to the invention or the emitting layer according to the invention.

[0170] Fluorescent emitters can also be present in the light-emitting layer of the device according to the invention or in the mixture according to the invention. Preferred fluorescent emitting compounds are selected from the class of arylamines, wherein preferably at least one of the aromatic or heteroaromatic ring systems of the arylamine is a fused ring system, particularly preferably with at least 14 ring atoms. Preferred examples thereof are aromatic anthraceneamines, aromatic anthracenediamines, aromatic pyreneamines, aromatic pyrenediamines, aromatic chryseneamines, or aromatic chrysenediamines. An aromatic anthraceneamine is understood to be a compound in which one diarylamino group is bonded directly to one anthracene group, preferably in the 9-position. An aromatic anthracenediamine is understood to be a compound in which two diarylamino groups are bonded directly to one anthracene group, preferably in the 9,10-position.Aromatic pyrenamines, pyrenediamines, chrysenamines, and chrysenediamines are defined analogously, with the diarylamino groups on the pyrene preferably being bonded in the 1-position or 1,6-position. Further preferred emitting compounds are indenofluorenamines or diamines, benzoindenofluorenamines or diamines, and dibenzoindenofluorenamines or diamines, as well as indenofluorene derivatives with fused aryl groups. Pyrenearylamines are also preferred. Also preferred are benzoindenofluoreneamines, benzofluoreneamines, extended benzoindenofluorenes, phenoxazines, and fluorene derivatives linked to furan units or thiophene units. Furthermore, the light-emitting device or the mixture according to the invention can also contain materials that exhibit TADF (thermally activated delayed fluorescence).

[0171] In a further preferred embodiment of the present invention, the at least one light-emitting layer of the organic electroluminescent device can comprise, in addition to the host materials (matrix materials) 1 and 2, as described above or described as preferred, further host materials or matrix materials, so-called mixed-matrix systems. These mixed-matrix systems preferably comprise three or four different matrix materials, particularly preferably three different matrix materials (i.e., a further matrix component in addition to the host materials 1 and 2, as described above). Particularly suitable matrix materials, which can be used in combination as a matrix component of a mixed-matrix system, are selected from wide-open-gap materials, bipolar host materials, electron-transport materials (ETMs), and hole-transport materials (HTMs).

[0172] According to yet another embodiment of the present invention, the mixture contains no further components, i.e., functional materials, apart from the components of the host material of formula (1) and the host material 2, as described above. These are material mixtures that are used as such to produce the light-emitting layer. These mixtures are also referred to as premix systems, which are used as the sole material source during the vapor deposition of the host materials for the light-emitting layer and which have a constant mixing ratio during vapor deposition. This enables the vapor deposition of a layer with a uniform distribution of the components to be achieved in a simple and rapid manner, without the need for precise control of a large number of material sources.

[0173] According to an alternative embodiment of the present invention, the mixture contains, in addition to the components of the host material of formula (1) and the host material 2, as described above, a phosphorescent emitter as described above. With a suitable mixing ratio during vapor deposition, this mixture can also be used as the sole material source, as described above.

[0174] Preferred are premix systems consisting of two matrix materials, namely a compound of formula (I), in particular formula (Ia), and a compound of one of formulas (2) to (5) and (8) to (13).

[0175] Also preferred are premix systems consisting of three matrix materials, namely a compound of formula (1), in particular formula (1a), and two compounds of formulas (2) to (5) and (8) to (13).

[0176] The components or constituents of the light-emitting layer of the device according to the invention can thus be processed by vapor deposition or from solution. The material combination of host materials 1 and 2, as described above or preferably described, optionally with the phosphorescent emitter, as described above or preferably described, is provided for this purpose in a formulation containing at least one solvent. Suitable formulations have been described previously.

[0177] The light-emitting layer in the device according to the invention according to the preferred embodiments and the emitting compound preferably contains between 99.9 and 1 vol.%, more preferably between 99 and 10 vol.%, particularly preferably between 98 and 60 vol.%, very particularly preferably between 97 and 80 vol.% of matrix material made of at least one compound of the formula (1) and at least one compound of one of the formulas (2) to (5) and (8) to (13)(7), (8), (9), (10) or (11) according to the preferred embodiments, based on the total composition of emitter and matrix material. Accordingly, the light-emitting layer in the device according to the invention preferably contains between 0.1 and 99 vol.%, more preferably between 1 and 90 vol.%, particularly preferably between 2 and 40 vol.%, very particularly preferably between 3 and 20 vol.-% of the emitter based on the total composition of the light-emitting layer consisting of emitter and matrix material. If the compounds are processed from solution, the corresponding amounts in wt.% are preferred instead of the above-mentioned amounts in vol.%.

[0178] The present invention also relates to an organic electroluminescent device as described above or preferably described, wherein the organic layer contains a hole injection layer (HIL) and / or a hole transport layer (HTL), whose hole injecting material and hole transporting material belong to the class of arylamines.

[0179] The sequence of layers in the organic electroluminescent device according to the invention is preferably as follows:

[0180] Anode / hole injection layer / hole transport layer / emitting layer / hole blocking layer / electron transport layer / electron injection layer / cathode.

[0181] This sequence of layers is a preferred sequence.

[0182] It should be noted again that not all of the layers mentioned need to be present and / or that additional layers may be present.

[0183] In addition to the compounds of formula (1) according to the invention, all materials used in the prior art as electron-transport materials in the electron-transport layer can be used as materials for the electron-transport layer. Particularly suitable are aluminum complexes, for example Alq3, zirconium complexes, for example Zrq4, benzimidazole derivatives, triazine derivatives, pyrimidine derivatives, pyridine derivatives, pyrazine derivatives, quinoxaline derivatives, quinoline derivatives, oxadiazole derivatives, aromatic ketones, lactams, boranes, diazaphosphole derivatives, and phosphine oxide derivatives.

[0184] Suitable cathodes for the device according to the invention include metals with low work functions, metal alloys, or multilayer structures made of different metals, such as alkaline earth metals, alkali metals, main group metals, or lanthanides (e.g., Ca, Ba, Mg, Al, In, Mg, Yb, Sm, etc.). Alloys made of an alkali or alkaline earth metal and silver, for example, an alloy of magnesium and silver, are also suitable. In multilayer structures, in addition to the metals mentioned, other metals with a relatively high work function, such as Ag or Al, can also be used. Combinations of the metals, such as Ca / Ag, Mg / Ag, or Ba / Ag, are then generally used. It may also be preferable to introduce a thin intermediate layer of a material with a high dielectric constant between a metallic cathode and the organic semiconductor.Suitable materials for this purpose include alkali metal or alkaline earth metal fluorides, as well as the corresponding oxides or carbonates (e.g., LiF, Ü2O, BaF2, MgO, NaF, CsF, CS2CO3, etc.). Lithium quinolinate (LiQ) can also be used. The thickness of this layer is preferably between 0.5 and 5 nm.

[0185] Materials with a high work function are preferred as anodes. The anode preferably has a work function greater than 4.5 eV vs. vacuum. Metals with a high redox potential, such as Ag, Pt, or Au, are suitable for this purpose. Metal / metal oxide electrodes (e.g., Al / Ni / NiO) can also be used. x , AI / PtO x) may be preferred. For some applications, at least one of the electrodes must be transparent or partially transparent in order to enable either the irradiation of the organic material (organic solar cell) or the coupling out of light (OLED, O-LASER). Preferred anode materials here are conductive mixed metal oxides. Particular preference is given to indium tin oxide (ITO) or indium zinc oxide (IZO). Also preferred are conductive, doped organic materials, in particular conductive doped polymers. Furthermore, the anode can also consist of several layers, for example an inner layer made of ITO and an outer layer made of a metal oxide, preferably tungsten oxide, molybdenum oxide or vanadium oxide.

[0186] The organic electroluminescent device according to the invention is structured, contacted and finally sealed accordingly (depending on the application) during production, since the lifetime of the devices according to the invention is shortened in the presence of water and / or air.

[0187] The production of the device according to the invention is not restricted in this regard. It is possible for one or more organic layers, including the light-emitting layer, to be coated using a sublimation process. The materials are vapor-deposited in vacuum sublimation systems at an initial pressure of less than 10'5 mbar, preferably less than 10'6 mbar. However, it is also possible for the initial pressure to be even lower, for example, less than 10'6 mbar.

[0188] The organic electroluminescent device according to the invention is preferably characterized in that one or more layers are coated using the OVPD (Organic Vapor Phase Deposition) process or by means of carrier gas sublimation. The materials are applied at a pressure between 10'5 mbar and 1 bar. A special case of this process is the OVJP (Organic Vapor Jet Printing) process, in which the materials are applied directly through a nozzle and thus structured (e.g., BMS Arnold et al., Appl. Phys. Lett. 2008, 92, 053301).

[0189] Furthermore, the organic electroluminescent device according to the invention is preferably characterized in that one or more organic layers comprising the composition according to the invention are produced from solution, for example by spin coating, or by any printing process, such as screen printing, flexographic printing, nozzle printing, or offset printing, but particularly preferably LITI (Light Induced Thermal Imaging, thermal transfer printing) or inkjet printing. Soluble host materials 1 and 2 and phosphorescent emitters are required for this purpose. Processing from solution has the advantage that, for example, the light-emitting layer can be applied very easily and cost-effectively. This technique is particularly suitable for the mass production of organic electroluminescent devices.

[0190] Furthermore, hybrid processes are possible, in which, for example, one or more layers are applied from solution and one or more further layers are vapor-deposited.

[0191] These methods are generally known to the person skilled in the art and can be applied to organic electroluminescent devices.

[0192] A further subject of the invention is therefore a method for producing the organic electroluminescent device according to the invention, as described above or preferably described, characterized in that the organic layer, preferably the light-emitting layer, the hole injection layer and / or hole transport layer, is applied by vapor phase deposition, in particular with a sublimation process and / or with an OVPD (Organic Vapor Phase Deposition) process and / or with the aid of carrier gas sublimation, or from solution, in particular by spin coating or with a printing process.

[0193] When manufactured by vapor deposition, there are basically two ways in which the organic layer according to the invention, preferably the light-emitting layer, can be applied or vapor-deposited onto any substrate or the previous layer. Firstly, the materials used can each be placed in a material source and then evaporated from the various material sources ("co-evaporation"). Secondly, the various materials can be premixed ("premixed" systems) and the mixture placed in a single material source, from which it is then vaporized ("premix evaporation"). This allows for the vapor deposition of the light-emitting layer with a uniform distribution of the components in a simple and rapid manner, without the need for precise control of a large number of material sources.

[0194] A further subject of the invention is therefore a method for producing the device according to the invention, characterized in that the light-emitting layer of the organic layer is applied by gas phase deposition, wherein the at least one compound of formula (1) together with the further materials forming the light-emitting layer are deposited successively or simultaneously from at least two material sources from the gas phase.

[0195] In a preferred embodiment of the present invention, the light-emitting layer is applied by vapor deposition, wherein the components of the composition are premixed and evaporated from a single material source.

[0196] A further subject of the invention is therefore a method for producing the device according to the invention, characterized in that the light-emitting layer of the organic layer is applied by gas phase deposition, wherein the at least one compound of formula (1) together with at least one further matrix material as a premix, successively or simultaneously with the light-emitting materials selected from the group of phosphorescent emitters, fluorescent emitters and / or emitters which exhibit TADF (thermally activated delayed fluorescence), are deposited from the gas phase.

[0197] The electronic devices according to the invention, in particular organic electroluminescent devices, are characterized by one or more of the following surprising advantages over the prior art:

[0198] 1. Electronic devices, in particular organic electroluminescent devices containing compounds according to formula (1) or the preferred embodiments described above and below, in particular as matrix material or as electron-conducting materials, exhibit a very long lifetime. These compounds, in particular, result in low roll-off, i.e., a low drop in the power efficiency of the device at high luminance levels.

[0199] 2. Electronic devices, in particular organic electroluminescent devices containing compounds of formula (1) or the preferred embodiments described above and below as electron-conducting materials and / or matrix materials, exhibit excellent efficiency. Compounds of the invention according to formula (1) or the preferred embodiments described above and below result in a low operating voltage when used in electronic devices.

[0200] 3. The compounds according to the invention according to formula (1) or the preferred embodiments described above and below show a very high stability and lifetime.

[0201] 4. Using compounds according to formula (1) or the preferred embodiments described above and below, the formation of optical loss channels can be avoided in electronic devices, particularly organic electroluminescent devices. As a result, these devices are characterized by high PL and thus high EL efficiency of emitters and excellent energy transfer from the matrices to dopants.

[0202] 5. The use of compounds according to formula (1) or the preferred embodiments described above and below in layers of electronic devices, in particular organic electroluminescent devices, leads to a high mobility of the electron conductor structures.

[0203] 6. Compounds according to formula (1) or the preferred embodiments described above and below have excellent glass film formation.

[0204] 7. Compounds according to formula (1) or the preferred embodiments described above and below form very good films from solutions.

[0205] 8. The compounds according to formula (1) or the preferred embodiments described above and below have a deep triplet level Ti, which can be, for example, in the range of 2.50 eV - 2.90 eV.

[0206] These advantages mentioned above are not accompanied by an excessive deterioration of the other electronic properties.

[0207] It should be noted that variations of the embodiments described in the present invention fall within the scope of this invention. Any feature disclosed in the present invention may, unless explicitly excluded, be replaced by alternative features serving the same, equivalent, or similar purpose. Thus, unless otherwise stated, any feature disclosed in the present invention is to be considered an example of a generic series or an equivalent or similar feature.

[0208] All features of the present invention may be combined with each other in any way, unless certain features and / or steps are mutually exclusive. This applies in particular to preferred features of the present invention. Likewise, features of non-essential combinations may be used separately (and not in combination).

[0209] The technical teaching disclosed in the present invention can be abstracted and combined with other examples. The invention is further illustrated by the following examples without intending to limit it. Examples:

[0210] General methods:

[0211] The Gaussian16 program package (Rev. B.01) is used for all quantum chemical calculations. The neutral singlet ground state is optimized at the B3LYP / 6-31G(d) level. HOMO and LUMO values ​​are determined at the B3LYP / 6-31G(d) level for the ground state energy optimized with B3LYP / 6-31G(d).

[0212] TD-DFT singlet and triplet excitations (vertical excitations) are then calculated using the same method (B3LYP / 6-31G(d)) and the optimized ground-state geometry. The default settings for SCF and gradient convergence are used.

[0213] From the energy calculation, the HOMO is determined as the last orbital occupied by two electrons (alpha occupancy eigenvalues) and LIIMO as the first unoccupied orbital (alpha virtual eigenvalues) in Hartree units, where HEh and LEh represent the HOMO energy in Hartree units and the LUMO energy in Hartree units, respectively. From this, the HOMO and LUMO values ​​in electronvolts, calibrated using cyclic voltammetry measurements, are determined as follows:

[0214] HOMOcorr = 0.90603 * HOMO - 0.84836

[0215] LUMOcorr = 0.99687 * LUMO - 0.72445

[0216] The triplet level T1 of a material is defined as the relative excitation energy (in eV) of the lowest energy triplet state resulting from quantum chemical energy calculations.

[0217] The singlet level S1 of a material is defined as the relative excitation energy (in eV) of the singlet state with the second lowest energy, which results from the quantum chemical energy calculation.

[0218] The lowest energy singlet state is called SO.

[0219] The method described here is independent of the software package used and always yields the same results. Examples of commonly used programs for this purpose are "Gaussian09" (Gaussian Inc.) and Q-Chem 4.1 (Q-Chem, Inc.). In this case, the program package "Gaussian16 (Rev. B.01)" is used to calculate the energies. OLED fabrication

[0220] In the following examples V1 to V10 and E1 to E15 (see Tables 7 and 8) the data of different OLEDs are presented.

[0221] Pretreatment for examples V1 to V10 and E1 to E15:

[0222] Glass plates coated with 50 nm of patterned ITO (indium tin oxide) are coated with 20 nm of PEDOT:PSS (poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate), supplied as CLEVIOS™ P VP AI 4083 from Heraeus Precious Metals GmbH, Germany, spin-coated from aqueous solution) for improved processing. These coated glass plates form the substrates onto which the OLEDs are applied.

[0223] OLEDs generally have the following layer structure: substrate / hole transport layer (HTL) / optional interlayer (IL) / electron blocking layer (EBL) / emission layer (EML) / optional hole blocking layer (HBL) / electron transport layer (ETL) / optional electron injection layer (EIL), and finally a cathode. The cathode is formed by a 100 nm thick aluminum layer. The exact structure of the OLEDs can be found in Table 4. The materials required for OLED production are shown in Table 5.

[0224] All materials are thermally evaporated in a vacuum chamber. The emission layer always consists of at least one matrix material (host material) and an emissive dopant (emitter), which is mixed into the matrix material(s) by co-evaporation in a specific volume fraction. A specification such as IC1:IC3:TEG1 (55%:35%:10%) means that the IC1 material is present in the layer at a volume fraction of 55%, IC3 at a volume fraction of 35%, and TEG1 at a volume fraction of 10%. Similarly, the electron-transport layer can also consist of a mixture of two materials.

[0225] The OLEDs are characterized as standard. For this purpose, the electroluminescence spectra, current efficiency (measured in cd / A), power efficiency (measured in λ / W), and external quantum efficiency (EQE, measured in percent) are determined as a function of luminance, calculated from current-voltage-luminance characteristics (IUL characteristics) assuming a Lambertian radiation pattern, as well as the lifetime. The electroluminescence spectra are measured at a luminance of 1000 cd / m 2 and from this the CIE 1931 x and y color coordinates are calculated. The value U1000 in Table 2 refers to the voltage required for a luminance of 1000 cd / m 2 SE1000 and LE1000 indicate the power efficiency and performance efficiency, respectively, at 1000 cd / m 2 Finally, EQE1000 refers to the external quantum efficiency at an operating luminance of 1000 cd / m 2The lifetime LD is defined as the time after which the luminance drops from the initial luminance to a certain fraction L1 when operated at constant current. A value of LO;jO = ​​4000 cd / m 2 and L1 = 70% in Table 2 means that the lifetime given in column LD corresponds to the time after which the initial luminance of 4000 cd / m 2 to 2800 cd / m 2 Analogously, LO;jO = ​​20mA / cm 2 , L1 = 80%, that the luminance when operating at 20mA / cm 2 after the time LD drops to 80% of its initial value.

[0226] The data of the various OLEDs are summarized in Table 5. Examples V1-V5 are comparative examples according to the prior art, while examples E1-E15 show data from OLEDs according to the invention.

[0227] In the following, some of the examples are explained in more detail to illustrate the advantages of the OLEDs according to the invention.

[0228] Use of mixtures according to the invention in the emission layer of phosphorescent OLEDs

[0229] When used as matrix materials in phosphorescent OLEDs, the materials of the invention provide significant improvements over the prior art in terms of component lifetime (comparison of examples V1 / V2 with E1, E3, E5, and V3 with E2, as well as V4 with E3, V5 with E4, V6 with E2, V7 with E6, V8 with E10, V9 with E7, and V10 with E8). And as electronic conductors (comparison of examples V1 with E1, E14, E15).

[0230] Table 8: OLED data

[0231] Table 9: Structural formulas of the materials for the OLEDs

[0232]

Claims

Patent claims 1. Compound according to formula (1) where the symbols and indices used have the following meaning: L 1 is selected from the group consisting of a single bond, an aromatic ring system with 6 - 40 ring atoms or a heteroaromatic ring system with 5 - 40 ring atoms, wherein optionally both ring systems are independently partially or fully substituted with D; L 2 is a single bond or an aromatic ring system with 6 - 40 ring atoms, optionally partially or fully substituted with D; L 3 is selected from the group consisting of a single bond, an aromatic ring system with 6 - 40 ring atoms or a heteroaromatic ring system with 5 - 40 ring atoms, wherein optionally both ring systems are independently partially or fully substituted with D; Het is a group selected from Het (5); indicates the connection to L 2 ; Het 1 is selected from the group consisting of an aromatic ring system with 6 - 40 ring atoms, or a heteroaromatic ring system with 5 to 40 ring atoms, wherein, optionally, independently of each other, both ring systems are partially or completely substituted with R 3 substituted; R is selected at each occurrence, the same or different, from the A group consisting of H, D, F, CN, a straight-chain alkyl group having 1 to 20 C atoms or an alkenyl or alkynyl group having 2 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, where one or more non-adjacent CH2 groups may be replaced by O or S, and where at least one H atom may be replaced by D, F, or CN, or an aromatic ring system having 6 to 40 ring atoms or a heteroaromatic ring system having 5 to 40 ring atoms, in which at least one F atom may be replaced by D, F, Cl, Br, I or CN, and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; two or more adjacent substituents R may form an aliphatic, aromatic or heteroaromatic ring system with one another; R 1 is selected the same or different at each occurrence from the A group consisting of H, D, F, CN, a straight-chain alkyl group having 1 to 20 C atoms or an alkenyl or alkynyl group having 2 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, where one or more non-adjacent CH2 groups may be replaced by O or S, and where at least one H atom may be replaced by D, F, or CN, or an aromatic ring system having 6 to 40 ring atoms or a heteroaromatic ring system having 5 to 40 ring atoms, in which at least one H atom may be replaced by D, F, Cl, Br, I or CN and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; two or more adjacent substituents R may form an aliphatic, aromatic or heteroaromatic ring system with one another; R 2 is selected the same or different at each occurrence from the Group consisting of an aromatic ring system with 6 - 40 ring atoms or a heteroaromatic ring system with 5 to 40 ring atoms, where, optionally, both ring systems independently of each other are partially or completely substituted with R 4 are substituted; R 3 is selected the same or different at each occurrence from the Group consisting of H, D, F, CN, a straight-chain alkyl group with 1 to 20 C atoms or an alkenyl or alkynyl group with 2 to 20 C atoms or a branched or cyclic alkyl group with 3 to 20 C atoms, where one or more non-adjacent CH2 groups can be replaced by O or S and where at least one H atom can be replaced by D, F, or CN or an aromatic ring system with 6 to 40 C atoms or heteroaromatic ring system with 5 to 40 ring atoms, in which at least one Fl atom can be replaced by D, F, Cl, Br, I or CN and which can be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; two or more adjacent substituents R can form an aliphatic, aromatic or heteroaromatic ring system with one another; R 4 is selected the same or different at each occurrence from the Group consisting of H, D, F, CN, n is 3 when m is 4 or m is 3 when n is 4; and wherein the following compound is excluded from the invention:

2. A compound according to claim 1, wherein the compound is a compound according to formula (1a): Formula (Ia), wherein the symbols and indices used have the meaning according to claim 1.

3. A compound according to claim 1 or 2, wherein HEt 1 is selected from the group consisting of an aromatic ring system with 6 - 25 ring atoms or a heteroaromatic ring system with 5 to 24 ring atoms, wherein, optionally, independently of each other, both ring systems are partially or completely substituted with R 4 are substituted.

4. A compound according to one or more of claims 1 to 3, wherein Het is selected from the group consisting of Het (1), Het (2), Het (3) or Het (5).

5. A compound according to one or more of claims 1 to 4, wherein L 1is selected from the group consisting of a single bond, an aromatic ring system with 6 to 25 ring atoms or a heteroaromatic ring system with 5 to 18 ring atoms, wherein optionally both ring systems are independently partially or fully substituted with D.

6. A compound according to one or more of claims 1 to 5, wherein L 3 is selected from the group consisting of a single bond, an aromatic ring system with 6 to 24 ring atoms or a heteroaromatic ring system with 5 to 18 ring atoms, wherein optionally both ring systems are independently partially or fully substituted with D.

7. A mixture comprising at least one compound according to one or more of claims 1 to 6 and at least one further compound selected from the group of matrix materials, phosphorescent emitters, fluorescent emitters and / or emitters exhibiting TADF (thermally activated delayed fluorescence).

8. Formulation comprising at least one compound according to one or more of claims 1 to 6 or a mixture according to claim 7 and at least one solvent.

9. Organic electroluminescent device comprising an anode, a cathode and at least one organic layer containing at least one compound according to one or more of claims 1 to 6.

10. Organic electroluminescent device according to claim 9, wherein the organic layer comprises at least one electron-transporting layer containing the compounds according to one or more of claims 1 to 6.

11. Organic electroluminescent device according to claim 9 or 10, wherein the organic layer comprises at least one light-emitting layer containing the compounds according to one or more of claims 1 to 6 as matrix material.

12. The organic electroluminescent device according to claim 11, wherein the light-emitting layer contains at least one further matrix material.

13. Organic electroluminescent device according to claim 12, wherein the at least one further matrix material is a compound according to formulas (2) to (5) and (8) to (12): where the symbols and indices used are: A 1 is C(R 7 )2, NR 7 , O or S; A is, at each occurrence independently, a group of the formula (6) or (7), Formula (8) X2 is the same or different at each occurrence CH, CR 6 or N, where a maximum of 2 symbols X2 can mean N; * indicates the binding site to formula (5); R 6 is, at each occurrence, identically or differently, D, CN, a straight-chain alkyl group having 1 to 20 C atoms or an alkenyl or alkynyl group having 2 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, where the alkyl, alkenyl or alkynyl group is each substituted by one or more radicals R 7 substituted and wherein one or more non-adjacent CH2 groups are replaced by Si(R 7 )2, C=O, NR 7 , O, S or CONR 7 may be replaced, or an aromatic or heteroaromatic ring system with 5 to 60 ring atoms, each of which is substituted by one or more radicals R 7 can be substituted; two radicals R 6also form an aromatic, heteroaromatic, aliphatic or heteroaliphatic ring system with each other; Ar is, at each occurrence, identically or differently, an aromatic or heteroaromatic ring system with 5 to 40 ring atoms, which is substituted with one or more radicals R 7 can be substituted; Ar 1 represents, identically or differently on each occurrence, an aromatic or heteroaromatic ring system having 5 to 40 ring atoms, which is substituted by one or more radicals R 7 can be substituted; R 7 is the same or different at each occurrence D, F, CI, Br, I, N(R 8 )2, CN, NO2, OR 8 , SR 8 , Si(R 8 )3, B(OR 8 )2, C(=O)R 8 , P(=O)(R 8 )2, S(=O)R 8 , S(=O)2R 8 , OSO2R 8, a straight-chain alkyl group having 1 to 20 C atoms or an alkenyl or alkynyl group having 2 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, wherein the alkyl, alkenyl or alkynyl group is each substituted by one or more radicals R 8 may be substituted, with one or more non-adjacent CH2 groups being substituted by Si(R 8 )2, C=O, NR 8 , O, S or CONR 8 may be replaced, or an aromatic or heteroaromatic ring system with 5 to 40 ring atoms, each of which is substituted by one or more radicals R 8 may be substituted; two or more radicals R 7 together form an aromatic, heteroaromatic, aliphatic or heteroaliphatic ring system, preferably the radicals R 7 no such ring system; R 8is, identically or differently at each occurrence, H, D, F or an aliphatic, aromatic or heteroaromatic organic radical, in particular a hydrocarbon radical, having 1 to 20 C atoms, in which one or more H atoms may be replaced by F; c, c1, c2 each independently at each occurrence denote 0 or 1 , where the sum of the indices c+c1+c2 is 1 at each occurrence; d, d1 , d2 each independently represent 0 or 1 , where the sum of the indices d + d1 + d2 is 1 at each occurrence; q, q1 , q2 each independently is 0 or 1 at each occurrence; s is the same or different at each occurrence and is 0, 1, 2, 3 or 4; t is the same or different at each occurrence: 0, 1, 2, or 3; u is the same or different at each occurrence: 0, 1, or 2; and v is 0 or 1.

14. An organic electroluminescent device according to claim 12, wherein the further matrix material is a compound of formula (13): Formula (13), where the symbols and indices used are: W is O, S, C(R 9 )2, N-Ar 2 ; R 9 is each independently a straight-chain or branched Alkyl group with 1 to 4 C atoms, which may be partially or fully deuterated, or an unsubstituted or partially or fully deuterated aromatic ring system with 6 to 18 C atoms, where two substituents R 9 with the C atom to which they are bonded, can form a mono- or polycyclic, aliphatic or aromatic or heteroaromatic unsubstituted, partially deuterated or fully deuterated ring system which can be substituted by one or more substituents R 12 can be substituted; Ar 2is at each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 30 ring atoms, which is substituted by one or more radicals R 12 can be substituted; two residues Ar 2 which bind to the same N-atom, P-atom or B-atom, also by a single bond or a bridge, selected from C(R 12 )2, O or S, may be bridged together; R 10 is selected at each occurrence, identically or differently, from the group consisting of F, CI, Br, I, CN, NO2, C(=O)R', P(=O)(AH)2, P(Ar 2 )2, B(Ar 2 )2, Si(A)3, Si(R')s, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 20 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms or an alkenyl group having 2 to 20 C atoms, each of which may be substituted by one or more radicals R', where one or more non-adjacent CH2 groups may be replaced by R'C=CR', Si(R')2, C=O, C=S, C=NR', P(=O)(R'), SO, SO2, NR', O, S or CONR' and where one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO2; R' is at each occurrence, identically or differently selected from the group consisting of D, F, CI, Br, I, CN, NO2, N(AH)2, NH2, N(R") 2IC(=O)AH, C(=O)H, C(=O)R“, P(=O)(AH)2, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms or an alkenyl or alkynyl group having 2 to 40 C atoms, each of which may be substituted by one or more radicals R“, where one or more non-adjacent CH2 groups may be replaced by HC=CH, R“C=CR“, C=C, Si(R')2, Ge(R")2, Sn(R")2, C=O, C=S, C=Se, C=NR“, P(=O)(R"), SO, SO2, NH, NR“, O, S, CONH or CONR“, and where one or more H atoms may be replaced by F, CI, Br, I, CN or NO2, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, each of which may be substituted by one or more radicals R", an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R", or a combination of these systems,where optionally two or more adjacent substituents R' may form a monocyclic or polycyclic, aliphatic, aromatic or heteroaromatic ring system which may be substituted by one or more radicals R";, R" is, at each occurrence, identically or differently selected from the group consisting of D, F, CN, an aliphatic hydrocarbon radical having 1 to 20 C atoms or an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, in which one or more H atoms may be replaced by D, F, CI, Br, I or CN and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms; two or more adjacent substituents R 3 together a mono- or polycyclic, form aliphatic ring system; it came from these definitions - however, I find it too broad, I will use the following definition for my foreign version - thanks for finding the error R' is, at each occurrence, identically or differently, an aliphatic, aromatic or heteroaromatic organic radical, in particular a hydrocarbon radical, having 1 to 20 C atoms, in which one or more H atoms may be replaced by F; R 11 is selected at each occurrence, identically or differently, from the group consisting of F, CI, Br, I, CN, NO2, N(Ar 2 )2, NH2, N(R 12 )2, C(=O)Ar 2 , C(=O)H, C(=O)R 5 , P(=O)(Ar 2)2, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl group having 3 to 40 C atoms or an alkenyl or alkynyl group having 2 to 40 C atoms, each of which is substituted by one or more radicals R 12 may be substituted, where one or more non-adjacent CH2 groups are substituted by HC=CH, R 12 C=CR 12 , C=C, Si(R 12 )2, Ge(R 12 )2, Sn(R 12 )2, C=O, C=S, C=Se, C=NR 12 , P(=O)(R 12 ), SO, SO2, NH, NR 12 , O, S, CONH or CONR 12 and wherein one or more H atoms may be replaced by D, F, CI, Br, I, CN or NO2, an aromatic or heteroaromatic ring system having 5 to 60 ring atoms, each of which is substituted by one or more radicals R 12 may be substituted, an aryloxy or heteroaryloxy group having 5 to 60 ring atoms, which may be substituted with one or more radicals R 12may be substituted, or a combination of these systems, optionally two or more adjacent substituents R 11 can form a monocyclic or polycyclic, aliphatic, aromatic or heteroaromatic ring system which can be substituted with one or more radicals R 12 can be substituted; R 12 is selected, identically or differently at each occurrence, from the group consisting of D, F, CN, a straight-chain alkyl group having 1 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, where one or more non-adjacent CH2 groups may be replaced by O or S and where one or more H atoms may be replaced by D, F, or CN or an aromatic or heteroaromatic ring system having 5 to 30 ring atoms, in which one or more H atoms may be replaced by D, F, Cl, Br, I or CN and which is substituted by one or more alkyl groups each having 1 to 4 carbon atoms; two or more adjacent substituents R 12 together form a mono- or polycyclic, aliphatic ring system; x, x1 are each independently 0, 1, 2, 3 or 4; y, z are each independently 0, 1 or 2; a1, a2 are each independently 0, 1, 2, 3, 4 or 5; a3 is 0, 1, 2 or 3; a4 is 0, 1, 2, 3 or 4.

15. Organic electroluminescent device according to one or more of the Claims 11 to 14, wherein the light-emitting layer contains a phosphorescent emitter.

16. Organic electroluminescent device according to one or more of the Claims 8 to 15, wherein it is an electroluminescent device selected from the group consisting of organic light-emitting transistors (OLETs), organic field quench devices (OFQDs), organic light-emitting electrochemical cells (OLECs, LECs, LEECs), organic laser diodes (O-lasers), and organic light-emitting diodes (OLEDs).

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