EP3947372A1

EP3947372A1 - Materials for organic electroluminescent devices

Info

Publication number: EP3947372A1
Application number: EP20711950.4A
Authority: EP
Inventors: Amir Hossain Parham; Jonas Valentin Kroeber; Jens ENGELHART; Anja JATSCH; Christian EICKHOFF; Christian Ehrenreich
Original assignee: Merck Patent GmbH
Current assignee: Merck Patent GmbH
Priority date: 2019-03-25
Filing date: 2020-03-23
Publication date: 2022-02-09
Also published as: US20220216424A1; CN113614082B; CN113614082A; KR20210143247A; WO2020193447A1

Abstract

The invention relates to compounds which are suitable for use in electronic devices, and to electronic devices, in particular organic electroluminescent devices, containing said compounds.

Description

Materials for organic electroluminescent devices

The present invention relates to materials for use in electronic devices, in particular in organic electroluminescent devices, and electronic devices, in particular organic electroluminescent devices containing them

Materials.

In organic electroluminescent devices (OLEDs), phosphorescent organometallic complexes are often used as emitting materials. In general, there is still a need for improvement in OLEDs, especially also in OLEDs that show triplet emission (phosphorescence), for example with regard to efficiency, operating voltage and service life. The properties of phosphorescent OLEDs are not only determined by the triplet emitters used. The other materials used, such as matrix materials, are of particular importance here. Improvements in these materials can therefore also lead to improvements in the OLED properties. Suitable matrix materials for OLEDs are, for example, aromatic lactams, such as. B. in WO 2011/116865, WO

2011/137951 or WO 2013/064206 disclosed.

The object of the present invention is to provide compounds which are suitable for use in an OLED, in particular as matrix material for phosphorescent emitters or as electron transport material, and there lead to improved properties. Another object of the present invention is to provide further organic semiconductors for organic electroluminescent devices

in order to allow the person skilled in the art a greater choice of materials for the production of OLEDs.

Surprisingly, it has been found that certain compounds described in more detail below solve this problem and are well suited for use in OLEDs. In particular, the OLEDs have a long service life, improved efficiency and a lower operating voltage. These connections, as well as electronic devices, in particular organic electroluminescent devices which contain these compounds are therefore the subject of the present invention.

The present invention relates to a compound of the formula (1),

The following applies to the symbols used:

A, B are each selected from the group consisting of NAr ¹ , C = 0, C = S, C = NR, BR, PR, P (= 0) R, SO and SO2, with the proviso that one of the symbols A and B stands for NAr ¹ and the other of the symbols A and B stands for C = 0, C = S, C = NR, BR, PR, P (= 0) R, SO or S0 ₂ ;

Cy is together with the two explicitly drawn carbon atoms a group of the following formula (2),

Dashed bonds denote the linkage of this group in the formula (1);

X, identically or differently on each occurrence, is CR or N; or two adjacent groups X stand for a group of the following formula (3), and the two other symbols X stand identically or differently on each occurrence for CR or N, Formula (3) where the dashed bonds indicate the linkage of this group in the formula (1);

Y is, identically or differently on each occurrence, CR or N; or two adjacent groups Y represent a group of the following

Formula (3), and the two other symbols Y, identically or differently on each occurrence, represent CR or N,

Formula (3) where the dashed bonds indicate the linkage of this group in the formula (1);

A ¹ is identically or differently on each occurrence NAr ³ , 0, S or

C (R) ₂ ;

Z, identically or differently on each occurrence, is CR or N;

Ar ¹ , Ar ² , Ar ³ is on each occurrence, identically or differently, an aromatic or heteroaromatic ring system with 5 to 40 aromatic ring atoms, which can be substituted by one or more radicals R;

R is identically or differently on each occurrence Fl, D, F, CI, Br, I,

N (Ar ') ₂ , N (R ¹ ) ₂ , OAr', SAr ', CN, N0 ₂ , OR ¹ , SR ¹ , COOR ¹ , C (= 0) N (R ¹ ) ₂ , Si (R ¹ ) ₃ , B (OR ¹ ) ₂ , C (= 0) R ¹ , P (= 0) (R ¹ ) ₂ , S (= 0) R ¹ , S (= 0) ₂ R ¹ , 0S0 ₂ R ¹ , a straight-chain alkyl group with 1 to 20 carbon atoms or an alkenyl or alkynyl group with 2 to 20 carbon atoms or a branched or cyclic alkyl group with 3 to 20 carbon atoms, where the alkyl, alkenyl or alkynyl group can in each case be substituted by one or more radicals R ¹ , one or more non-adjacent CH ₂ groups being replaced by Si (R ¹ ) ₂ , C = 0, NR ¹ , 0, S or CONR ¹ can be replaced, or an aromatic or heteroaromatic ring system with 5 to 60 aromatic ring atoms, preferably with 5 to 40 aromatic ring atoms, each of which is substituted by one or more radicals R ¹ can be; two radicals R can also be an aliphatic,

form heteroaliphatic, aromatic or heteroaromatic ring system;

Ar 'is on each occurrence, identically or differently, an aromatic or heteroaromatic ring system with 5 to 40 aromatic ring atoms, which can be substituted by one or more radicals R ¹ ;

R ¹ is on each occurrence, identically or differently, H, D, F, CI, Br, I, N (R ² ) ₂ , CN, N0 _2I OR ² , SR ² , Si (R ² ) ₃ , B (OR ² ) ₂ , C (= 0) R ² , P (= 0) (R ² ) ₂ , S (= 0) R ² , S (= 0) ₂ R ² , 0S0 ₂ R ² , a straight chain alkyl group with 1 to 20 C atoms or an alkenyl or alkynyl group with 2 to 20 carbon atoms or a branched or cyclic alkyl group with 3 to 20 carbon atoms, it being possible for the alkyl, alkenyl or alkynyl group to be substituted by one or more radicals R ² , where one or more non-adjacent CH ₂ groups can be replaced by Si (R ² ) ₂ , C = 0, NR ² , O, S or CONR ² and where one or more H atoms in the alkyl, alkenyl or alkynyl group can be replaced by D, F, CI, Br, I or CN, or an aromatic or heteroaromatic ring system with 5 to 40 aromatic ring atoms, each of which can be substituted by one or more radicals R ² ; two or more radicals R ^{1 here} can form an aliphatic ring system with one another;

R 2 is on each occurrence, identically or differently, H, D, F, CN or an aliphatic, aromatic or heteroaromatic organic radical, in particular a hydrocarbon radical, with 1 to 20 C- Atoms in which one or more H atoms can also be replaced by F; with the proviso that at least one group R stands for a heteroaromatic ring system and / or that at least one group Ar ¹ or

Ar stands for a heteroaromatic ring system and / or that the connection has at least one group according to formula (3).

For the purposes of this invention, an aryl group contains 6 to 40 carbon atoms; For the purposes of this invention, a fleteroaryl group contains 2 to 40 carbon atoms and at least one fleteroatom, with the proviso that the sum of carbon atoms and fleteroatoms is at least 5. The fletero atoms are preferably selected from N, 0 and / or S. Here, under an aryl group or fleteroaryl group, either a simple aromatic cycle, i.e. benzene, or a simple heteroaromatic cycle, for example pyridine, pyrimidine, thiophene, etc., or a fused (fused) aryl or fleteroaryl group, for example naphthalene, anthracene, phenanthrene, quinoline, isoquinoline, etc., understood. In contrast, aromatics linked to one another by a single bond, such as biphenyl, are not referred to as an aryl or fleteroaryl group, but as an aromatic ring system.

An aromatic ring system for the purposes of this invention contains 6 to 60 carbon atoms, preferably 6 to 40 carbon atoms, in the ring system. A heteroaromatic ring system for the purposes of this invention contains 2 to 60 carbon atoms, preferably 2 to 40 carbon atoms and at least one fleteroatom in the ring system, with the proviso that the sum of carbon atoms and fletero atoms is at least 5. The fleteroatoms are preferably selected from N, O and / or S. An aromatic or heteroaromatic ring system in the context of this invention is understood to mean a system that does not necessarily contain only aryl or fleteroaryl groups, but also contains several aryl or fleteroaryl groups by a non-aromatic unit, such as. B. a C, N or O atom, the verbun can be. Likewise, systems are to be understood here in which two or more aryl or fleteroaryl groups are linked directly to one another, such as. B. biphenyl, terphenyl, bipyridine or Phenyl pyridine. For example, systems such as fluorene, 9,9'-spirobifluorene, 9,9-diarylfluorene, triarylamine, diaryl ether, stilbene, etc. are to be understood as aromatic ring systems for the purposes of this invention, and likewise systems in which two or more aryl groups

for example linked by a short alkyl group. Preferred aromatic or heteroaromatic ring systems are simple aryl or heteroaryl groups and groups in which two or more aryl or heteroaryl groups are linked directly to one another, for example biphenyl or bipyridine, and fluorene or spirobifluorene.

In the context of the present invention, an aliphatic hydrocarbon radical or an alkyl group or an alkenyl or alkynyl group, which can contain 1 to 40 carbon atoms, and in which also individual H atoms or CH ₂ groups are represented by the above-mentioned groups can be substituted, preferably the radicals methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, 2-methylbutyl, n-pentyl, s-pentyl, neo-pentyl , Cyclopentyl, n-hexyl, neo-hexyl, cyclohexyl, n-heptyl, cyclo-heptyl, n-octyl, cyclooctyl, 2-ethylhexyl, trifluoromethyl, pentafluoroethyl,

2.2.2-Trifluoroethyl, ethenyl, propynyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl or octynyl were understood. Among an alkoxy group OR ¹ with 1 to 40 carbon atoms, methoxy, trifluoromethoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, n-pentoxy, s- Pentoxy, 2-methylbutoxy, n-hexoxy, cyclohexyloxy, n-heptoxy, cycloheptyloxy, n-octyloxy, cyclooctyloxy, 2-ethylhexyloxy, pentafluoroethoxy and 2,2,2-trifluoroethoxy understood. A thioalkyl group SR ¹ with 1 to 40 carbon atoms includes, in particular, methylthio, ethylthio, n-propylthio, i-propylthio, n-butylthio, i-butylthio, s-butylthio, t-butylthio, n-pentylthio, s-pentylthio, n-hexylthio, cyclohexylthio, n-heptylthio, cycloheptylthio, n-octylthio, cyclooctylthio, 2-ethylhexylthio, trifluoromethylthio, pentafluoroethylthio,

2.2.2-trifluoroethylthio, ethenylthio, propenylthio, butenylthio,

Pentenylthio, Cyclopentenylthio, Hexenylthio, Cyclohexenylthio, Heptenylthio, Cycloheptenylthio, Octenylthio, Cyclooctenylthio, Ethynylthio,

Propynylthio, butynylthio, pentynylthio, hexynylthio, heptynylthio or octynylthio. In general, alkyl, alkoxy or Thioalkyl groups according to the present invention can be straight-chain, branched or cyclic, it being possible for one or more non-adjacent CH ₂ groups to be replaced by the abovementioned groups; furthermore, one or more H atoms can also be replaced by D, F, CI, Br, I, CN or N0 ₂ , preferably F, CI or CN, particularly preferably F or CN.

An aromatic or heteroaromatic ring system with 5-60 aromatic ring atoms, which can be substituted by the above mentioned radicals R ² or a hydrocarbon radical and which can be linked via any positions on the aromatic or fleteroaromatic, is understood to mean in particular groups those that are derived from benzene, naphthalene, anthracene, benzanthracene, phenanthrene, pyrene, chrysene, perylene, fluoranthene, naphthacene, pentacene, benzopyrene, biphenyl, biphenylene, terphenyl, triphenylene, fluorene, spirobifluorene, dihydrophenanthrene, dihydropyrenic Tetrahydropyrene, cis- or trans-indenofluorene, cis- or trans-indenocarbazole, cis- or trans -indolocarbazole, Truxen, Isotruxen, Spirotruxen, Spiroisotruxen, Furan, Benzofuran, Isobenzofuran, Dibenzofuran, Thiophene, Benzothibenzothiophen, Benzothibenzothiophen, Benzothibenzothiophen , Pyrrole, indole, isoindole, carbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo-5,6-quinoline, benzo-6, 7-quinoline, benzo-7,8-quinoline, phenothiazine,

Phenoxazine, pyrazole, indazole, imidazole, benzimidazole, naphthimidazole, phenanthrimidazole, pyridimidazole, pyrazineimidazole, quinoxaline imidazole, oxazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, 1, 2-thiazole, thiazole, benzazole, thiazole, 2-pyramidazole, thiazole, thiazole, benzothiazole, 3-pyrazole, phenylene, benzopyridazine, pyrimidine, benzpyrimidine, quinoxaline, 1,5-diazaanthracene, 2,7-diazapyren, 2,3-diazapyren, 1,6-diazapyren, 1,8-diazapyren, 4,5-diazapyren, 4,5, 9,10-tetraazaperylene, pyrazine,

Phenazine, phenoxazine, phenothiazine, fluorubine, naphthyridine,

Azacarbazole, benzocarboline, phenanthroline, 1, 2,3-triazole, 1, 2,4-triazole, benzotriazole, 1, 2,3-oxadiazole, 1, 2,4-oxadiazole, 1, 2,5-oxadiazole, 1, 3,4-oxadiazole, 1, 2,3-thiadiazole, 1, 2,4-thiadiazole, 1, 2,5-thiadiazole, 1, 3,4-thiadiazole, 1, 3,5-triazine, 1 , 2,4-triazine, 1, 2,3-triazine, tetrazole, 1, 2,4,5-tetrazine, 1, 2,3,4-tetrazine, 1, 2,3,5-tetrazine, purine , Pteridine, indolizine and Benzothiadiazole or groups derived from combinations of these systems.

The formulation that two or more radicals can form an aliphatic ring with one another should be understood in the context of the present description, inter alia, to mean that the two radicals are linked to one another by a chemical bond with formal elimination of two hydrogen atoms. This is illustrated by the following scheme:

Furthermore, the abovementioned formulation is also intended to mean that in the event that one of the two radicals is hydrogen, the second radical binds to the position to which the hydrogen atom was bound to form a ring. This should be made clear by the following scheme:

Ring formation

/ r \ /, / r \ A

the remainder R ^ / r \ //

R R H CH 'CFL' 2

Depending on the orientation of the group of formula (2), there are different isomers, as shown below by formulas (4) and (5),

Formula (4)

Formula (5) where the symbols used have the meanings given above.

In a preferred embodiment of the invention, one of the groups A and B stands for NAr ¹ , and the other of the groups A and B stands for C = 0, P (= 0) R, BR or SCh, in particular for C = 0.

Preferred embodiments of the compounds of the formula (4) are thus the compounds of the following formulas (4a) and (4b), and preferred embodiments of the compounds of the formula (5) are the compounds of the following formulas (5a) and (5b),

where the symbols used have the meanings given above. The compounds of the formula (5a) are particularly preferred.

In a preferred embodiment of the invention, a maximum of one symbol X stands for N, and the other symbols X stand the same or different for CR. In a particularly preferred embodiment of the invention, all symbols X, identically or differently, stand for CR. The compounds of the following formulas (4a-1), (4b-1), (5a-1) and (5b-1) are therefore particularly preferred, Formula (5a-1) Formula (5b-1) where the symbols used have the meanings given above.

In a further preferred embodiment of the invention, a maximum of one symbol Y stands for N and the other symbols Y stand for CR. In a particularly preferred embodiment of the invention, all symbols Y stand for CR. The compounds of the following formulas (4a-2), (4b-2), (5a-2) and (5b-2) are therefore particularly preferred,

where the symbols used have the meanings given above.

The abovementioned preferences for X and Y occur particularly preferably simultaneously, so that structures of the following formulas (4a-3), (4b-3), (5a-3) and (5b-3) are particularly preferred,

where the symbols used have the meanings given above.

In a preferred embodiment of the invention, a maximum of three radicals R, particularly preferably a maximum of two radicals R and very particularly preferably a maximum of one radical R in the compound of formula (1) or the preferred structures listed above represent a group other than hydrogen.

The compounds of the following formulas (4a-4), (4b-4), (5a-4) and (5b-4) are very particularly preferred,

Formula (5a-4) Formula (5b-4) where the symbols used have the meanings given above.

In a further embodiment of the invention, two adjacent groups Y represent a group of the formula (3) and the two other symbols Y, identically or differently, represent CR. The symbol A ¹ in the group of the formula (3) preferably stands for NAr ³ . If two groups Y stand for a group of the formula (3), preferred embodiments of the formula (4) are the compounds of the following formulas (6) to (11) and preferred embodiments of the formula (5) are the compounds of the following formulas (12) to (17),

orme () where the symbols used have the meanings given above. It is particularly preferred if one of the groups A and B is NAr ¹ and the other of the groups A and B is C = 0.

In formula (6) to (17), a maximum of one group X is preferably N and the other groups X are identical or different and are CR. Particularly preferably, all groups X, identically or differently, represent CR.

In a further preferred embodiment of the invention, at most one group Z stands for N, and the other groups Z, identically or differently, stand for CR. Particularly preferably, all of the Z groups, identically or differently, represent CR.

In the formulas (6) to (17), all symbols X and Z, identically or differently, are very particularly preferably CR, so that the compounds of the following formulas (6-1) to (17-1) are particularly preferred,

where the symbols used have the meanings given above.

It applies to formulas (6) to (17) and (6-1) to (17-1) that one of the groups A and B preferably stands for NAr ¹ and the other of the groups A and B stands for C = 0 . The structures of the following formulas (6a-1) to (17b-1) are therefore particularly preferred,

17th

where the symbols used have the meanings given above. In a preferred embodiment of the invention, a maximum of three radicals R, particularly preferably a maximum of two radicals R and very particularly preferably a maximum of one radical R in these compounds represent a group other than hydrogen.

The compounds of the following formulas (6a-2) to (17b-2) are very particularly preferred,

Formula (13a-2)

Formula (13b-2) Formula (17b-2) where the symbols used have the meanings given above.

In a further embodiment of the invention, two adjacent groups X stand for a group of the formula (3) and the two other symbols X stand identically or differently for CR. The symbol A in the group of formula (3) preferably stands for NAr ³ . If two groups X represent a group of the formula (3), preferred embodiments of the formula (4) are the compounds of the following formulas (18) to (23) and preferred embodiments of the formula (5) are the compounds of the following formulas ( 24) to (29),

where the symbols used have the meanings given above.

In formula (18) to (29), a maximum of one group Y preferably represents N and the other groups Y, identically or differently, represent CR. Particularly preferably, all groups Y, identically or differently, represent CR. In a further preferred embodiment of the invention, at most one group Z represents N, and the other groups Z, identically or differently, represent CR. Particularly preferably, all of the Z groups, identically or differently, represent CR.

In the formulas (18) to (29), all symbols Y and Z, identically or differently, are very particularly preferably CR, so that the compounds of the following formulas (18-1) to (29-1) are particularly preferred,

where the symbols used have the meanings given above.

For the formulas (18) to (29) and (18-1) to (29-1), one of the groups A and B is preferably NAr ¹ and the other of the groups A and B is C = 0 stands. The structures of the following formulas (18a-1) to (29b-1) are therefore particularly preferred,

Formula (29a-1) Formula (29b-1) where the symbols used have the meanings given above.

In a preferred embodiment of the invention, a total of a maximum of three radicals R, particularly preferably a maximum of two radicals R and very particularly preferably a maximum of one radical R in these compounds represent a group other than hydrogen.

The compounds of the following formulas (18a-2) to (29b-2) are very particularly preferred,

where the symbols used have the meanings given above.

Preferred substituents Ar ¹ , Ar ² , Ar ³ , R, Ar ', R ¹ and R ² on the compounds according to the invention are described below. In a particularly preferred embodiment of the invention, the preferences mentioned below for Ar ¹ , Ar ² , Ar ³ , R, Ar ', R ¹ and R ^{2 occur} simultaneously and apply to the structures of the formula (1) and to all of the above preferred embodiments.

In a preferred embodiment of the invention, Ar ¹ , Ar ² and Ar ^{3 are,} identically or differently, on each occurrence an aromatic or heteroaromatic ring system with 6 to 30 aromatic ring atoms which can be substituted by one or more radicals R. Particularly preferably, Ar ¹ , Ar ² and Ar ^{3 are} identical or different on each occurrence, an aromatic or heteroaromatic ring system with 6 to 24 aromatic ring atoms, in particular with 6 to 13 aromatic ring atoms, which is replaced by one or more, preferably non-aromatic, R radicals can be substituted. If Ar ¹ , Ar ² or Ar ^{3 stands} for a fleteroaryl group, in particular for triazine, pyrimidine, quinazoline or carbazole, aromatic or heteroaromatic substituents R on this fleteroaryl group can also be preferred. It can furthermore be preferred if Ar ¹ , Ar ² or Ar ³ is substituted by a group N (Ar ') ₂ , so that the substituent Ar ¹ , Ar ² or Ar ³ altogether is a triarylamine or triheteroarylamine group represents. Suitable aromatic or heteroaromatic ring systems Ar ¹ , Ar ² or Ar ³ are selected identically or differently on each occurrence from the group consisting of 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, fluorene, which can be linked via the 1-, 2-, 3- or 4-position, spirobifluorene, which can be linked via the 1 -, 2-, 3- or 4-position, naphthalene, which can be linked via the 1- or 2-position, indole, benzofuran, benzothiophene, carbazole, which can be linked via the 1-, 2-, 3- or 4-position can be linked, dibenzofuran, which can be linked via the 1-, 2-, 3- or 4-position, dibenzothiophene, which can be linked via the 1-, 2-, 3- or 4-position, Indenocarbazole, indolocarbazole, pyridine, pyrimidine, pyrazine, pyridazine, triazine, quinoline, quinazoline, benzimidazo l,

Phenanthrene, triphenylene or a combination of two or three of these groups, which can each be substituted with one or more radicals R, preferably non-aromatic radicals R. If Ar ¹ , Ar ² or Ar ^{3 is} a heteroaryl group, in particular triazine, pyrimidine, quinazoline or carbazole, aromatic or heteroaromatic radicals R on this heteroaryl group can also be preferred.

Ar ¹ , Ar ² and Ar ^{3 are} preferably the same or different on each occurrence selected from the groups of the following formulas Ar-1 to Ar-83,

 where R and A ^{1 have} the meanings given above, the dashed bond represents the bond to the nitrogen atom and the following also applies:

Ar ⁴ is on each occurrence, identically or differently, a bivalent aromatic or heteroaromatic ring system with 6 to 18 aromatic ring atoms, which can in each case be substituted by one or more radicals R; n is 0 or 1, where n = 0 means that there are none at this position

Group A ^{1 is} bonded and radicals R are bonded to the corresponding carbon atoms instead; m is 0 or 1, where m = 0 means that the group Ar ^{4 is} not present and that the corresponding aromatic or heteroaromatic group is bonded directly to the nitrogen atom.

In a preferred embodiment of the invention, R is selected on each occurrence identically or differently from the group consisting of H, D, F, N (Ar ') ₂ , CN, OR ¹ , a straight-chain alkyl group with 1 to 10 carbon atoms or an alkenyl group with 2 to 10 carbon atoms or a branched or cyclic alkyl group with 3 to 10 carbon atoms, where the alkyl or alkenyl group can in each case be substituted by one or more radicals R ¹ , but is preferably unsubstituted, and where one or more non-adjacent CH ₂ groups are replaced by 0 can be, or an aromatic or heteroaromatic ring system with 6 to 30 aromatic ring atoms, each of which can be substituted by one or more radicals R ¹ ; two radicals R here can also form an aliphatic, aromatic or heteroaromatic ring system with one another. R is particularly preferably selected identically or differently on each occurrence from the group consisting of H, N (Ar ') ₂ , a straight-chain alkyl group with 1 to 6 carbon atoms, in particular with 1, 2, 3 or 4 carbon atoms, or a branched or cyclic alkyl group with 3 to 6 carbon atoms, where the alkyl group can in each case be substituted with one or more radicals R ¹ , but is preferably unsubstituted, or an aromatic or heteroaromatic ring system with 6 to 24 aromatic ring atoms, each can be substituted by one or more radicals R ¹ , preferably non-aromatic radicals R ¹ . R is very particularly preferably selected identically or differently on each occurrence from the group consisting of H or an aromatic or heteroaromatic ring system with 6 to 24 aromatic ring atoms, each of which is represented by one or more radicals R ¹ , preferably non-aromatic radicals R ¹ , can be substituted. It can furthermore be preferred if R stands for a triaryl or -heteroarylamine group which can be substituted by one or more radicals R ¹ . This group is an embodiment of an aromatic or heteroaromatic ring system, in which case several aryl or

Heteroaryl groups are linked together by a nitrogen atom. If R stands for a triaryl or heteroarylamine group, this group preferably has 18 to 30 aromatic ring atoms and can be substituted by one or more radicals R ¹ , preferably non-aromatic radicals R ¹ .

In a further preferred embodiment of the invention, Ar 'is an aromatic or heteroaromatic ring system with 6 to 30 aromatic ring atoms, which can be substituted by one or more radicals R ¹ . In a particularly preferred embodiment of the invention Ar 'is an aromatic or heteroaromatic ring system with 6 to 24 aromatic ring atoms, in particular with 6 to 13 aromatic ring atoms, which can be substituted by one or more, preferably non-aromatic, radicals R ¹ .

Suitable aromatic or heteroaromatic ring systems R or Ar 'are selected from phenyl, biphenyl, especially ortho-, meta- or para-biphenyl, terphenyl, especially ortho-, meta-, para- or branched terphenyl, quaterphenyl, especially ortho- , meta-, para- or branched quaterphenyl, fluorene, which can be linked via the 1-, 2-, 3- or 4-position, spirobifluorene, which is linked via the 1-, 2-, 3- or 4-position can, naphthalene, which can be linked via the 1- or 2-position, indole, benzofuran, benzothiophene, carbazole, which can be linked via the 1-, 2-, 3- or 4-position, dibenzofuran, which can be linked via the 1-, 2-, 3- or 4-position, dibenzothiophene, which can be linked via the 1-, 2-, 3- or 4-position, indenocarbazole, indolocarbazole, pyridine, pyrimidine, pyrazine , Pyridazine, triazine, quinoline, quinazoline, benzimidazole,

Phenanthrene, triphenylene or a combination of two or three of these groups, each of which can be substituted with one or more radicals R ¹ . If R or Ar 'stands for a heteroaryl group, in particular triazine, pyrimidine, quinazoline or carbazole, aromatic or heteroaromatic radicals R ¹ on this heteroaryl group can also be preferred.

The groups R, if they stand for an aromatic or heteroaromatic ring system, or Ar 'are preferably selected from the groups of the following formulas R-1 to R-83,

35

 where R ^{1 has} the meanings given above, the dashed bond denotes the bond to a carbon atom of the basic structure in formula (1), (2) and (3) or in the preferred embodiments or to the nitrogen atom in the group N (Ar ' ) ₂ and the following also applies:

Ar ⁴ is on each occurrence, identically or differently, a bivalent aromatic or heteroaromatic ring system with 6 to 18 aromatic ring atoms, which can in each case be substituted by one or more radicals R ¹ ;

A ¹ is on each occurrence, identically or differently, C (R ¹ ) ₂ , NR ¹ , 0 or S; n is 0 or 1, where n = 0 means that there are none at this position

Group A ^{1 is} bonded and radicals R ^{1 are} bonded to the corresponding carbon atoms instead; m is 0 or 1, where m = 0 means that the group Ar ⁴ does not exist and that the corresponding aromatic or heteroaromatic group is directly attached to a carbon atom of the basic structure in formula (1) or in the preferred embodiments or is bonded to the nitrogen atom in the group N (Ar ') ₂ ; with the proviso that m = 1 for the structures (R-12), (R-17), (R-21), (R-25), (R-26), (R-30), (R -34), (R-38) and (R-39), if these groups are embodiments of Ar '.

If the above-mentioned groups Ar-1 to Ar-83 for Ar ¹ , Ar ² or Ar ³ and R-1 to R-83 for R or Ar 'have several groups A ¹ , all combinations for this come from the definition of A ¹ in question. Preferred embodiments are then those in which one group A ^{1 is} NR or NR ¹ and the other group A ^{1 is} C (R) ₂ or C (R ¹ ) ₂ , or in which both groups A ^{1 are} NR or NR ¹ stand or in which both groups A ¹ stand for 0. In a particularly preferred embodiment of the invention, in groups Ar ¹ , Ar ² , Ar ³ , R or Ar 'which have several groups A ¹ , at least one group A ^{1 is} C (R) ₂ or C (R ¹⁾ ) ₂ or for NR or NR ¹ .

If A ^{1 stands} for NR or NR ¹ , the substituent R or R ¹ , which is bonded to the nitrogen atom, preferably stands for an aromatic or heteroaromatic ring system with 5 to 24 aromatic ring atoms, which is also characterized by one or more radicals R ¹ or R ² can be substituted. In a particularly preferred embodiment, this substituent R or R ^1, identically or differently on each occurrence, represents an aromatic or heteroaromatic ring system with 6 to 24 aromatic ring atoms, preferably with 6 to 12 aromatic ring atoms, which have no condensed aryl groups or fleteroaryl groups in which two or more aromatic or heteroaromatic 6-ring groups are fused directly to one another, and which in each case can also be substituted by one or more radicals R ¹ or R ² . Particularly preferred are phenyl, biphenyl, terphenyl and quaterphenyl with linkage patterns such as those listed above for Ar-1 to Ar-11 or R-1 to R-11, these structures being represented by one or more R ¹ and R ² radicals can be substituted, but are preferably unsubstituted.

If A ^{1 stands} for C (R) 2 or C (R ¹ ) 2, the substituents R and R ¹ , which are bonded to this carbon atom, are preferably identical or different on each occurrence for a linear alkyl group with 1 to 10 carbon atoms or for a branched or cyclic alkyl group with 3 to 10 carbon atoms or for an aromatic or heteroaromatic ring system with 5 to 24 aromatic ring atoms, which can also be substituted by one or more radicals R ¹ or R ² . R or R ¹ very particularly preferably represents a methyl group or a phenyl group. The radicals R and R ^{1 can} also form a ring system with one another, which leads to a spiro system.

As described above, it is essential to the invention that the compound has at least one radical R which stands for a heteroaromatic ring system, and / or that at least one group Ar ¹ or Ar ^{2 stands} for a heteroaromatic ring system and / or that the compound is a group of formula (3).

In one embodiment of the invention, at least one radical R is an electron-rich heteroaromatic ring system. The electron-rich heteroaromatic ring system is preferably selected from the groups R-13 to R-42 shown above, where in the groups R-13 to R-16, R-18 to R-20, R-22 to R-24, R -27 to R-29, R-31 to R-33 and R-35 to R-37 at least one group A ^{1 represents} NR ¹ , where R ¹ preferably represents an aromatic or heteroaromatic ring system, in particular an aromatic ring system. The group R-15 with m = 0 and A ¹ = NR ¹ is particularly preferred.

In a further embodiment of the invention, at least one radical R is an electron-poor heteroaromatic ring system. The electron-poor heteroaromatic ring system is preferably selected from the groups R-47 to R-50, R-57, R-58 and R-76 to R-83 shown above. In a further embodiment of the invention, Ar ¹ and / or Ar ^{2 stands} for an electron-poor heteroaromatic ring system. The electron-poor heteroaromatic ring system is preferably selected from the groups Ar-47 to Ar-50, Ar-57, Ar-58 and Ar-76 to Ar-83 shown above.

In a further preferred embodiment of the invention, R ^1, identically or differently on each occurrence, is selected from the group consisting of H, D, F, CN, OR ² , a straight-chain alkyl group with 1 to 10 carbon atoms or an alkenyl group with 2 to 10 C atoms or a branched or cyclic alkyl group with 3 to 10 C atoms, where the alkyl or alkenyl group can in each case be substituted by one or more radicals R ² and where one or more non-adjacent CF groups can be replaced by O. , or an aromatic or heteroaromatic ring system with 6 to 30 aromatic ring atoms, each of which can be substituted by one or more radicals R ² ; two or more radicals R ^{1 here} can form an aliphatic ring system with one another. In a particularly preferred embodiment of the invention, R ^1, identically or differently on each occurrence, is selected from the group consisting of H, one

straight-chain alkyl group with 1 to 6 carbon atoms, in particular with 1, 2, 3 or 4 carbon atoms, or a branched or cyclic alkyl group with 3 to 6 carbon atoms, it being possible for the alkyl group to be substituted by one or more radicals R ² , but is preferably unsubstituted, or an aromatic or heteroaromatic ring system with 6 to 24 aromatic ring atoms, each of which can be substituted by one or more radicals R ² , but is preferably unsubstituted.

In a further preferred embodiment of the invention, R ^2, identically or differently on each occurrence, is H, F, an alkyl group with 1 to 4 carbon atoms or an aryl group with 6 to 10 carbon atoms, which is associated with an alkyl group with 1 to 4 carbon atoms Atoms can be substituted, but is preferably unsubstituted.

Further suitable groups Ar ¹ , Ar ² , Ar ³ , R or Ar 'are groups of the formula -Ar ⁷ -N (Ar ⁵ ) (Ar ⁶ ), where Ar ⁵ , Ar ⁶ and Ar ^{7 are} identical or different each occurrence for an aromatic or heteroaromatic ring system with 5 to 24 aromatic ring atoms, which can be substituted by one or more radicals R or R ¹ . For Ar ¹ , Ar ² or Ar ³ , such a group results in that the group Ar ¹ , Ar ² or Ar ³ is substituted by a group N (Ar ') ₂ . The total number of aromatic ring atoms of Ar ⁵ , Ar ⁶ and Ar ^{7 is} a maximum of 60 and preferably a maximum of 40.

Ar ⁷ and Ar ⁵ can be connected to one another and / or Ar ⁵ and Ar ^{6 to} one another by a group selected from C (R ¹ ) ₂ , NR ¹ , O or S. The linkage of Ar ⁷ and Ar ^{5 to} one another or of Ar ⁵ and Ar ^{6 to} one another is preferably carried out in each case ortho to the position of the linkage with the nitrogen atom. In a further embodiment of the invention, none of the groups Ar ⁵ , Ar ⁶ or Ar ⁷ are connected to one another.

Ar ⁷ is preferably an aromatic or heteroaromatic ring system with 6 to 24 aromatic ring atoms, in particular with 6 to 12 aromatic ring atoms, which can be substituted by one or more radicals R ¹ . Ar ⁷ is particularly preferably selected from the group consisting of ortho-, meta- or para-phenylene or ortho-, meta- or para-biphenyl, which can each be substituted by one or more radicals R ¹ , but are preferably unsubstituted. Ar ⁷ is very particularly preferably an unsubstituted phenylene group. This is especially true when Ar ^{7 is} linked to Ar ⁵ by a single bond

connected is.

Ar ⁵ and Ar ⁶ are preferably, identically or differently on each occurrence, an aromatic or heteroaromatic ring system with 6 to 24 aromatic ring atoms, which can in each case be substituted by one or more radicals R ¹ . Particularly preferred groups Ar ⁵ and Ar ⁶ are selected identically or differently on each occurrence from the group consisting of benzene, ortho-, meta- or para-biphenyl, ortho-, meta-, para- or branched terphenyl, ortho-, meta -, para- or branched quaterphenyl, 1-, 2-, 3- or 4-fluorenyl, 1-, 2-, 3- or 4- spirobifluorenyl, 1- or 2-naphthyl, indole, benzofuran, benzothiophene, 1-, 2-, 3- or 4-carbazole, 1-, 2-, 3- or 4-dibenzofuran, 1-, 2-, 3- or 4- dibenzothiophene, indenocarbazole, indolocarbazole, 2-, 3- or 4 -Pyridine,

2-, 4- or 5-pyrimidine, pyrazine, pyridazine, triazine, phenanthrene, triphenylene or combinations of two, three or four of these groups, which can each be substituted by one or more radicals R ¹ . Particularly preferably, Ar ⁵ and Ar ^6, identically or differently on each occurrence, represent an aromatic ring system with 6 to 24 aromatic ring atoms, which can be substituted by one or more radicals R ¹ , in particular selected from the groups consisting of benzene, biphenyl, especially ortho-, meta- or para-biphenyl, terphenyl, especially ortho-, meta-, para- or branched terphenyl, quaterphenyl, especially ortho-, meta-, para- or branched quaterphenyl, fluorene, especially 1-, 2-, 3- or 4-fluorene, or spirobifluorene, in particular 1-, 2-, 3- or 4-spirobifluorene.

The alkyl groups in compounds according to the invention which are processed by vacuum evaporation preferably have no more than five carbon atoms, particularly preferably no more than 4 carbon atoms, very particularly preferably no more than 1 carbon atom. For compounds that are processed from solution, compounds are also suitable which are substituted with alkyl groups, in particular branched alkyl groups, with up to 10 carbon atoms or which are substituted with oligoarylene groups, for example ortho-, meta-, para- or branched terphenyl or quaterphenyl groups.

If the compounds of the formula (1) or the preferred embodiments are used as matrix material for a phosphorescent emitter or in a layer that is directly adjacent to a phosphorescent layer, it is further preferred if the compound does not contain condensed aryl or contains heteroaryl groups in which more than two six-membered rings are fused directly to one another. In particular, it is preferred that the groups Ar ¹ , Ar ² , Ar ³ , R, Ar ', R ¹ and R ² contain no condensed aryl or heteroaryl groups in which two or more six-membered rings are fused directly to one another. Exceptions to this are phenanthrene and triphenylene, which are due to may be preferred for their high triplet energy despite the presence of fused aromatic six-membered rings.

The above-mentioned preferred embodiments can be combined with one another as desired within the restrictions defined in claim 1. In a particularly preferred embodiment of the invention, the abovementioned preferences occur simultaneously.

Examples of suitable compounds according to the embodiments listed above are the compounds listed in the table below.



The basic structure of the compounds according to the invention is known in the literature. This can be functionalized according to the ways outlined in Scheme 1 and 2. The indoloquinolinone basic structure can be functionalized by halogenation, for example with NBS, followed by a coupling reaction, for example a Suzuki coupling. The indole nitrogen atom and the lactam nitrogen atom can then be substituted, for example by Buchwald coupling or by Ullmann coupling (Scheme 1). The synthesis of

Compounds with a fused-on group of the formula (3) also start from the halogenated skeleton (Scheme 2). This is coupled with an ortho-nitrobenzene boronic acid derivative, followed by a cyclization reaction. The indole nitrogen atoms and the lactam nitrogen atom can then be substituted, for example by Buchwald coupling or by Ullmann coupling. Further derivatives can be synthesized analogously.

Scheme 1:

Scheme 2:

For the processing of the compounds according to the invention from the liquid phase, for example by spin coating or by printing processes, formulations of the compounds according to the invention are required. These formulations can be, for example, solutions, dispersions or emulsions. It can 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, especially 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-dimethyl anisole, 3,5-dimethyl anisole, acetophenone, a-terpineol, benzothiazole, butyl benzoate, cumene, cyclohexanol, cyclohexanone, cyclohexylbenzene, decalin, dodecylbenzene, ethylbenzoate, indane, NMP, p-cymene, phenetol., 1, 4-diol, - Isopropylbenzene, dibenzyl ether, diethylene glycol butyl methyl ether, triethylene glycol butyl methyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, diethylene glycol monobutyl ether, tripropylene glycol, dimethylbenzene, 1-methylbenzene, 1-pentylbenzene, 1-octylbenzene, 1-octylbenzene-1-methylbenzene, 1-octylbenzene-1-methylbenzene, 1-pentylbenzene-1-methylbenzene, 1-pentylbenzene-1-methylbenzene henyl) ethane, 2-methylbiphenyl, 3-methylbiphenyl, 1-methylnaphthalene, 1-ethylnaphthalene, ethyl octanoate, diethyl sebacate, octyl octanoate, heptylbenzene, menthyl isovalerate, cyclohexylhexanoate or mixtures of these solvents. The present invention therefore also relates to a formulation comprising a compound according to the invention and at least one further compound. The further compound can, for example, be a solvent, in particular one of the above-mentioned solvents or a mixture of these solvents. The further compound can, however, also be at least one further organic or inorganic compound which is also used in the electronic device, for example an emitting compound and / or a further matrix material. Suitable emitting compounds and other matrix materials are listed below in connection with the organic electric luminescent device.

The compounds according to the invention are suitable for use in an electronic device, in particular in an organic electroluminescent device.

Another object of the present invention is therefore the use of a compound according to the invention in an electronic device, in particular in an organic electroluminescent device.

Yet another subject matter of the present invention is an electronic device containing at least one compound according to the invention.

An electronic device within the meaning of the present invention is a device which contains at least one layer which contains at least one organic compound. The component can also contain inorganic materials or layers that are made entirely of inorganic materials.

The electronic device is preferably selected from the group consisting of organic electroluminescent devices (OLEDs), organic integrated circuits (O-ICs), organic field-effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors ( O-LETs), organic solar cells (O-SCs), dye-sensitized organic solar cells (DSSCs), organic optical detectors, organic photoreceptors, organic field quench devices (O-FQDs), light-emitting electrochemical cells (LECs), organic laser diodes (O-lasers) and “Organic plasmon emitting devices”, but preferably organic electroluminescent devices (OLEDs), particularly preferably phosphorescent OLEDs.

The organic electroluminescent device contains a cathode, anode and at least one emitting layer. In addition to these layers, it can also contain further layers, for example one or more hole injection layers, hole transport layers, hole blocking layers, electron transport layers, electron injection layers, exciton blocking layers, electron blocking layers and / or

Charge-Generation Layers. Interlayers, which for example have an exciton-blocking function, can also be introduced between two emitting layers.

It should be noted, however, that it is not necessary for each of these layers to be present. The organic electroluminescent device can contain an emitting layer, or it can contain a plurality of emitting layers. If several emission layers are present, these preferably have a total of several emission maxima between 380 nm and 750 nm, so that overall white emission results, ie. H. Various emitting compounds that can fluoresce or phosphoresce are used in the emitting layers. Systems with three emitting layers are particularly preferred, the three layers showing blue, green and orange or red emission. The organic electroluminescent device according to the invention can also be a tandem OLED, in particular for white-emitting OLEDs.

The compound according to the invention according to the embodiments listed above can be used in different layers, depending on the precise structure. Preference is given to an organic electroluminescent device containing a compound of the formula (1) or the preferred embodiments set out above in one emitting layer as a matrix material for phosphorescent emitters or for emitters that show TADF (thermally activated delayed fluorescence), in particular for phosphorescent emitters. The organic electroluminescent device can contain an emitting layer, or it can contain a plurality of emitting layers, at least one emitting layer containing at least one compound according to the invention as a matrix material. Furthermore, the compound according to the invention can also be used in an electron transport layer and / or in a hole blocking layer and / or in a hole transport layer and / or in an exciton blocking layer.

If the compound according to the invention is used as a matrix material for a phosphorescent compound in an emitting layer, it is preferably used in combination with one or more phosphorescent materials (triplet emitters). Phosphorescence in the context of this invention is understood to mean the luminescence from an excited state with higher spin multiplicity, that is to say a spin state> 1, in particular from an excited triplet state. For the purposes of this application, all luminescent complexes with transition metals or lanthanides, in particular all iridium, platinum and copper complexes, are to be regarded as phosphorescent compounds.

The mixture of the compound of the invention and the

The emitting compound contains between 99 and 1% by volume, preferably between 98 and 10% by volume, particularly preferably between 97 and 60% by volume, in particular between 95 and 80% by volume of the compound according to the invention, based on the Total mixture of emitter and matrix material. Correspondingly, the mixture contains between 1 and 99% by volume, preferably between 2 and 90% by volume, particularly preferably between 3 and 40% by volume, in particular between 5 and 20% by volume of the emitter based on the total mixture Emitter and matrix material.

Another preferred embodiment of the present invention is the use of the compound according to the invention as a matrix material for a phosphorescent emitter in combination with another matrix material. 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, e.g. B. according to WO 2004/013080, WO 2004/093207, WO 2006/005627 or WO 2010/006680, triarylamines, carbazole derivatives, e.g. B. CBP (N, N-biscarbazolylbiphenyl) or those in WO 2005/039246, US 2005/0069729, JP 2004/288381, EP 1205527, WO 2008/086851 or WO 2013/041176, indolocarbazole derivatives, e.g. B. according to WO 2007/063754 or WO 2008/056746, indenocarbazole derivatives, e.g. B. according to WO

2010/136109, WO 2011/000455, WO 2013/041176 or WO

2013/056776, azacarbazole derivatives, e.g. B. according to EP 1617710, EP

1617711, EP 1731584, JP 2005/347160, bipolar matrix materials, e.g. B. according to WO 2007/137725, silanes, e.g. B. according to WO 2005/111172, aza borole or boronic ester, z. B. according to WO 2006/117052, triazine derivatives, e.g. B. according to WO 2007/063754, WO 2008/056746, WO 2010/015306, WO 2011/057706, WO 2011/060859 or WO 2011/060877, zinc complexes, e.g. B. according to EP 652273 or WO 2009/062578, diazasilol or tetra azasilol derivatives, z. B. according to WO 2010/054729, diazaphosphole derivatives, e.g. B. according to WO 2010/054730, bridged carbazole derivatives, e.g. B. according to WO 2011/042107, WO 2011/060867, WO 2011/088877 and WO 2012/143080, triphenylene derivatives, e.g. B. according to WO 2012/048781, or dibenzofuran derivatives, e.g. B. according to WO 2015/169412, WO

2016/015810, WO 2016/023608, WO 2017/148564 or WO

2017/148565. A further phosphorescent emitter, which emits with a shorter wave than the actual emitter, can also be present as a co-host in the mixture, or a compound that does not participate or does not participate to a significant extent in the charge transport, as described for example in WO 2010/108579.

In a preferred embodiment of the invention, the

Materials used in combination with another matrix material. If the compound according to the invention is substituted with an electron-poor heteroaromatic ring system, for example with triazine or quinazo lin, preferred co-matrix materials are selected from the group of bis-carbazoles, bridged carbazoles, triarylamines, the dibenzofuran-carbazole derivatives or dibenzofuran-amine derivatives and the carbazolamines.

Preferred biscarbazoles are the structures of the following formulas (30) and (31),

where R, Ar ¹ and A ^{1 have} the meanings given above. In a preferred embodiment of the invention, A ^{1 is} CR2.

Preferred embodiments of the compounds of the formulas (30) and (31) are the compounds of the following formulas (30a) and (31a),

where the symbols used have the meanings given above.

Examples of suitable compounds according to formula (30) or (31) are the compounds shown below.



Preferred bridged carbazoles are the structures of the following formula (32), where A ¹ and R have the meanings given above and A ^{1 is} preferably selected identically or differently on each occurrence from the group consisting of NAr ¹ and CR2.

Preferred dibenzofuran derivatives are the compounds of the following formula (33),

where the oxygen can also be replaced by sulfur, so that a dibenzothiophene is formed, L stands for a single bond or an aromatic or heteroaromatic ring system with 5 to 30 aromatic ring atoms, which can also be substituted by one or more radicals R, and R and Ar ^{1 have} the meanings given above. The two groups Ar ¹ , which bind to the same nitrogen atom, or a group Ar ¹ and a group L, which bind to the same nitrogen atom, can also be connected to one another, for example to form a carbazole.

Examples of suitable dibenzofuran derivatives are the compounds shown below.

Preferred carbazolamines are the structures of the following formulas (34), (35) and (36),

where L stands for an aromatic or heteroaromatic ring system with 5 to 30 aromatic ring atoms, which can be substituted by one or more radicals R, and R and Ar ^{1 have} the meanings given above.

Examples of suitable carbazolamine derivatives are the compounds shown below.

In particular if the compound according to the invention is substituted with an aromatic ring system or an electron-rich heteroaromatic ring system, for example a carbazole group, or has a group of the formula (3), preferred co-matrix materials are selected from the group consisting of triazine derivatives, pyrimidine Derivatives and quinazoline derivatives. Preferred triazine, quinazoline or pyrimidine derivatives, which can be used as a mixture together with the compounds according to the invention, are the compounds of the following formulas (37), (38) and (39),

where Ar ¹ and R have the meanings given above.

The triazine derivatives of the formula (37) and the quinazoline derivatives of the formula (39), in particular the triazine derivatives of the formula (37), are particularly preferred.

In a preferred embodiment of the invention, Ar ^{1 is} in the

Formulas (37), (38) and (39) on each occurrence, identically or differently, an aromatic or heteroaromatic ring system with 6 to 30 aromatic ring atoms, in particular with 6 to 24 aromatic ring atoms, which can be substituted by one or more radicals R. Suitable aromatic or heteroaromatic ring systems Ar ^{1 are} the same as those set out above as embodiments for Ar ¹ , Ar ² and Ar ³ , in particular the structures Ar-1 to Ar-83.

Examples of suitable triazine compounds which can be used as matrix materials together with the compounds according to the invention are the compounds shown in the table below.



Examples of suitable quinazoline compounds are the compounds shown in the following table: Particularly suitable phosphorescent compounds (= triplet emitters) are compounds which, with suitable excitation, emit light, 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 , especially a metal with this atomic number. Compounds containing copper, molybdenum, tungsten, rhenium, ruthenium, osmium, rhodium, iridium, palladium, platinum, silver, gold or europium are preferably used as phosphorescent emitters, in particular compounds containing iridium or platinum.

Examples of the emitters described above can be found in the applications WO 00/70655, WO 2001/41512, WO 2002/02714, WO 2002/15645, EP 1191613, EP 1191612, EP 1191614, WO 05/033244, WO 05/019373,

US 2005/0258742, WO 2009/146770, WO 2010/015307, WO

2010/031485, WO 2010/054731, WO 2010/054728, WO 2010/086089, WO 2010/099852, WO 2010/102709, WO 2011/032626, WO

2011/066898, WO 2011/157339, WO 2012/007086, WO 2014/008982, WO 2014/023377, WO 2014/094961, WO 2014/094960, WO

2015/036074, WO 2015/104045, WO 2015/117718, WO 2016/015815, WO 2016/124304, WO 2017/032439, WO 2018/011186 and WO

2018/041769, WO 2019/020538, WO 2018/178001 and the as yet unpublished patent applications EP 17206950.2 and EP 18156388.3. In general, all phosphorescent complexes are suitable as they are used according to the prior art for phosphorescent OLEDs and as they are known to the person skilled in the art in the field of organic electroluminescence, and the person skilled in the art can use further phosphorescent complexes without inventive effort.

Examples of phosphorescent dopants are listed below.



In the further layers of the organic electroluminescent device according to the invention, all materials can be used as they are usually used according to the prior art. The person skilled in the art can therefore use all materials known for organic electroluminescent devices in combination with the compounds according to the invention according to formula (1) or the preferred embodiments set out above, without inventive intervention.

An organic electroluminescent device is also preferred, characterized in that one or more layers are coated with a sublimation process. The materials in vacuum sublimation systems become smaller at an initial pressure

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 ⁷ mbar.

An organic electroluminescent device is likewise preferred, characterized in that one or more layers are coated with the OVPD (Organic Vapor Phase Deposition) process or with the aid of a 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.

Also preferred is an organic electroluminescent device, characterized in that one or more layers of solution, such as. B. by spin coating, or with any printing process, such as. B. screen printing, flexographic printing, offset printing, LITI (Light Induced Thermal Imaging, thermal transfer printing), ink-jet printing (inkjet printing) or nozzle printing. This requires soluble compounds, which can be obtained, for example, by suitable substitution.

Hybrid processes are also possible in which, for example, one or more layers are applied from solution and one or more additional layers are vapor-deposited.

These methods are generally known to the person skilled in the art and can be applied by him to organic Elektrolumineszenzvor devices containing the compounds according to the invention without any inventive step.

The compounds according to the invention and the organic electroluminescent devices according to the invention are distinguished by one or more of the following surprising advantages over the prior art:

1. The compounds according to the invention, used as matrix material for phosphorescent emitters, lead to long lifetimes.

2. The compounds according to the invention lead to high efficiencies.

This is particularly true when the compounds are used as matrix material for a phosphorescent emitter. In particular, the efficiency is better than in the case of comparable compounds which, however, have no heteroaromatic substituents and no group of the formula (3).

3. The compounds according to the invention lead to low operating voltages. This is particularly true when the compounds are used as matrix material for a phosphorescent emitter. In particular, the operating voltage is lower than in the case of comparable compounds which, however, have no heteroaromatic substituents and no group of the formula (3). The invention is explained in more detail by the following examples, without wishing to restrict it thereby. The person skilled in the art can use the descriptions to carry out the invention in the entire disclosed range and, without inventive work, produce further compounds according to the invention and use them in electronic devices or apply the method according to the invention.

Examples:

Synthesis examples

Unless otherwise stated, the following syntheses are carried out under a protective gas atmosphere in dried solvents. The solvents and reagents can be obtained from ALDRICH or ABCR. The numbers given for the starting materials that are not commercially available are the corresponding CAS numbers. a) 10-Bromo-5,7-dihydroindolo [2,3-c] quinolin-6-one

A solution of 36 g (154 mmol) of 5,7-dihydroindolo [2,3-c] quinolin-6-one in chloroform (1000 mL) is added in portions at 0 ° C with exclusion of light with 24.7 g (139 mmol) / V- Bromosuccinimide was added and the mixture was stirred at this temperature for 2 h. The reaction is ended by adding sodium sulfite solution and a further 30 min. stirred at room temperature. After phase separation, the organic phase is washed with water and the aqueous phase is extracted with dichloromethane. The combined organic phases are dried over sodium sulfate and concentrated in vacuo. The residue is dissolved in toluene and filtered through silica gel. The crude product is then recrystallized from toluene / heptane. Yield: 28.8 g (92 mmol), 60% of theory. Th., Colorless solid.

The following compounds can be obtained analogously: b) 10- (9-Phenylcarbazol-3-yl) -5,7-dihydroindolo [2,3-c] quinolin-6-one

21.9 g (70 mmol) 10-bromo-5,7-dihydroindolo [2,3-c] quinolin-6-one, 20.8 g

(75 mmol) phenylcarbazole-3-boronic acid and 14.7 g (139 mmol) sodium carbonate are suspended in 200 ml of toluene, 52 ml of ethanol and 100 ml of water. 80 mg (0.69 mmol) of tetrakistriphenylphosphine palladium (O) are added to this suspension, and the reaction mixture is heated under reflux for 16 h. After cooling, the organic phase is separated off, filtered through silica gel, washed three times with 200 ml of water and then concentrated to dryness. The residue is recrystallized from heptane / dichloromethane. The yield is 26.5 g (56 mmol), 80% of theory. Th ..

c) 8- (2-Nitrophenyl) -11-phenyl-5H-indolo [3,2-c] quinolin-6-one

A well-stirred, degassed suspension of 30 g (184 mmol) of 2-nitrophenylboronic acid, 70 g (180 mmol) of 8-bromo-11-phenyl-5H-indolo [3,2-c] quinolin-6-one and 66.5 g (212.7 mmol) of potassium carbonate in one

1.7 g (1.49 mmol) of Pd (PPh ₃ ) 4 are added to the mixture of 250 ml of water and 250 ml of THF and the mixture is heated under reflux for 17 h. After cooling, the organic phase is separated off, washed three times with 200 ml of water and once with 200 ml of saturated aqueous sodium chloride solution, dried over magnesium sulfate and evaporated to dryness. The gray residue is recrystallized from hexane. The precipitated crystals are filtered off with suction, washed with a little MeOH and dried in vacuo. Yield: 58 g (134 mmol); 75% d. Th ..

d) cyclization

A mixture of 94 g (220 mmol) 8- (2-nitrophenyl) -11 -phenyl-5H-indolo [3,2-c] quinolin-6-one and 290.3 ml (1669 mmol) triethyl phosphite is refluxed for 12 h . The remaining triethyl phosphite is then distilled off (72-76 ° C. / 9 mm Hg). The residue is mixed with water / MeOH (1: 1), the solid is filtered off and recrystallized. Yield: 62 g (156 mmol); 71% d. Th ..

The following compounds can be obtained analogously:

e) 7- (4,6-Diphenyl-1, 3,5-triazin-2-yl) -10- (9-phenylcarbazol-3-yl) -5H- indolo [2,3-c] quinolin-6- on

25 g (50 mmol) 10- (9-phenylcarbazol-3-yl) -5,7-dihydroindolo [2,3- c] quinolin-6-one and 16 g (60 mmol) 2-chloro-4,6- Diphenyl- [1,3,5] triazine are dissolved in 400 ml of toluene under an argon atmosphere. 1.0 g (5 mmol) of tri-tert-butyl-phosphine are added and the mixture is stirred under an argon atmosphere. 0.6 g (2 mmol) of Pd (OAc) ₂ are added and the mixture is stirred under an argon atmosphere, after which 9.5 g (99 mmol) of sodium Fe / f-butanolate are added. 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 MgS0 ₄ , filtered and the solvent is removed in vacuo. The residue is purified by column chromatography over silica gel (eluent: DCM / heptane (1: 4)). Yield 47 g (66 mmol); 63% d. Th ..

At 23c, 24c and 25c the residue is recrystallized from toluene and finally sublimed in a high vacuum (p = 5 × 10 ⁵ mbar). The purity is 99.9%.

The following compounds can be obtained analogously:

 f) 7- (4,6-Diphenyl-1,3,5-triazin-2-yl) -5-phenyl-10- (9-phenylcarbazol-3-yl) indolo [2,3-c] quinolin-6 -on

28.2 g (40 mmol) 7- (4,6-diphenyl-1,3,5-triazin-2-yl) -10- (9-phenylcarbazol-3-yl) -5H-indolo [2,3-c] quinolin-6-one, 61.2 g (85 mmol) 4-iodobenzene and 44.7 g (320 mmol) potassium carbonate, 3 g (16 mmol) copper (l) iodide and 3.6 g (16 mmol) 1,3-di- ( pyridin-2-yl) propane-1,3-dione are stirred in 100 ml of DMF at 150 ° C. for 30 h. The solution is diluted with water and extracted twice with ethyl acetate. The combined organic phases are dried over Na ₂ S0 ₄ and concentrated using a rotary evaporator. The residue is purified by chromatography (EtOAc / hexane: 2/3), recrystallized from toluene and finally sublimed in a high vacuum (p = 5 × 10 ⁵ mbar). The purity is 99.9%. The yield is 22.5 g (28 mmol), 72% of theory.

The following compounds can be obtained analogously:



Production of the OLEDs

The use of the materials according to the invention in OLEDs is presented in Examples E1 to E9 below (see Table 1).

Pretreatment for examples V1, E1 to E9: glass flakes coated with structured ITO (indium tin oxide) with a thickness of 50 nm, are treated with an oxygen plasma followed by an argon plasma prior to coating. These plasma-treated glass plates form the substrates on which the OLEDs are applied.

The OLEDs basically have the following layer structure: substrate / hole injection layer (HIL) / hole transport layer (HTL) / 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 is shown in Table 1. The materials required to manufacture the OLEDs are shown in Table 2.

All materials are thermally vapor deposited in a vacuum chamber. The emission layer always consists of at least one matrix material (host material, host material) and an emitting dopant (dopant, emitter), which is mixed with the matrix material or matrix materials in a certain volume proportion by co-vaporization. A specification such as IC1: SdT1: TEG1 (45%: 45%: 10%) means that the material IC1 in a volume proportion of 45%, SdT1 in a volume proportion of 45% and TEG1 in a volume proportion of 10% in the layer present. Similarly, the electron transport layer can also consist of a mixture of two materials.

The OLEDs are characterized as standard. For this purpose, the electroluminescence spectra, the current efficiency (SE, measured in cd / A) and the external quantum efficiency (EQE, measured in%) are determined as a function of the luminance, calculated from current-voltage-luminance characteristics assuming a Lambertian emission characteristic. The electroluminescence spectra are determined at a luminance of 1000 cd / m ² and the CIE 1931 x and y color coordinates are calculated therefrom. The results obtained in this way are shown in Table 3. Use of the materials according to the invention in OLEDs

The compounds EG1 to EG4 according to the invention are used in Examples E1 to E4 and E10 as matrix material in the emission layer of phosphorescent green OLEDs. For direct comparison, the prior art connection SdT1 is identical

Device structure characterized (V1). The compounds EG5 to EG9 according to the invention are used in Examples E5 to E9 as matrix material in the emission layer of phosphorescent red OLEDs.

Table 1: Structure of the OLEDs

Table 2: Structural formulas of the materials for the OLEDs

Table 3: Data of the OLEDs

Claims

1. Compound according to formula (1),

The following applies to the symbols used:

A, B are selected from the group consisting of NAr ¹ , C = 0, C = S, C = NR, BR, PR, P (= 0) R, SO and SO2, with the proviso that one of the symbols A and B stands for NAr ¹ and the other of the symbols A and B stands for C = 0, C = S, C = NR, BR, PR, P (= 0) R, SO or SO2;

Formula (2) where the dashed bonds denote the linkage of this group in formula (1);

X, identically or differently on each occurrence, is CR or N; or two adjacent groups X stand for a group of the formula (3), and the two other symbols X stand identically or differently on each occurrence for CR or N, Formula (3) where the dashed bonds indicate the linkage of this group in the formula (1);

Y is, identically or differently on each occurrence, CR or N; or two adjacent groups Y stand for a group of the formula (3), and the two other symbols Y stand identically or differently on each occurrence for CR or N,

A ¹ is identically or differently on each occurrence NAr ³ , 0, S or

C (R) ₂ ;

Z, identically or differently on each occurrence, is CR or N;

R is on each occurrence, identically or differently, H, D, F, CI, Br, I, N (Ar ') ₂ , N (R ¹ ) ₂ , OAr', SAr ', CN, N0 ₂ , OR ¹ , SR ¹ , COOR ¹ ,

C (= 0) N (R ¹ ) ₂ , Si (R ¹ ) ₃ , B (OR ¹ ) ₂ , C (= 0) R ¹ , P (= 0) (R ¹ ) ₂ , S (= 0) R ¹ , S (= 0) ₂ R ¹ , 0S0 ₂ R ¹ , a straight-chain alkyl group with 1 to 20 carbon atoms or an alkenyl or alkynyl group with 2 to 20 carbon atoms or a branched or cyclic alkyl group with 3 to 20 carbon atoms, where the alkyl, alkenyl or alkynyl group can in each case be substituted by one or more radicals R ¹ , one or more non-adjacent CH ₂ groups being replaced by Si (R ¹ ) ₂ , C = 0, NR ¹ , O, S or CONR ¹ can be replaced, or an aromatic or heteroaromatic ring system with 5 to 60 aromatic ring atoms, which can in each case be substituted by one or more radicals R ¹ ; two radicals R here can also form a ring system with one another;

R ¹ is on each occurrence, identically or differently, H, D, F, CI, Br, I, N (R ² ) ₂ , CN, N0 _2I OR ² , SR ² , Si (R ² ) ₃ , B (OR ² ) ₂ , C (= 0) R ² , P (= 0) (R ² ) ₂ , S (= 0) R ² , S (= 0) ₂ R ² , 0S0 ₂ R ² , a straight chain alkyl group with 1 to 20 C atoms or an alkenyl or alkynyl group with 2 to 20 carbon atoms or a branched or cyclic alkyl group with 3 to 20 carbon atoms, where the alkyl, alkenyl or alkynyl group can be substituted by one or more radicals R ² , where one or more non-adjacent CH ₂ groups can be replaced by Si (R ² ) ₂ , C = 0, NR ² , O, S or CONR ² and where one or more H atoms in the alkyl, alkenyl or alkynyl groups can be replaced by D, F, CI, Br, I or CN, or an aromatic or heteroaromatic ring system with 5 to 40 aromatic ring atoms, each of which can be substituted by one or more radicals R ² ; two or more radicals R ^{1 here} can form an aliphatic ring system with one another;

R ² is on each occurrence, identically or differently, H, D, F, CN or an aliphatic, aromatic or heteroaromatic organic radical with 1 to 20 carbon atoms, in which one or more F1 atoms can also be replaced by F; with the proviso that at least one group R stands for a heteroaromatic ring system and / or that at least one group Ar ¹ or Ar ^{2 stands} for a heteroaromatic ring system and / or that the compound has at least one group according to

Formula (3).

2. Compound according to claim 1 according to formula (4) or (5),

where the symbols used have the meanings given in claim 1.

3. A compound according to claim 1 or 2, characterized in that one of the groups A and B is NAr ¹ and the other of the groups A and B is C = 0.

4. A compound according to one or more of claims 1 to 3, selected from the compounds of the formulas (4a), (4b), (5a) and (5b),

where the symbols used have the meanings given in claim 1.

5. A compound according to one or more of claims 1 to 4, selected from the compounds of the formulas (4a-3), (4b-3), (5a-3) and (5b-3),

where the symbols used have the meanings given in claim 1.

6. A compound according to one or more of claims 1 to 4,

selected from the compounds of the formulas (6) to (29),

where the symbols used have the meanings given in claim 1.

7. A compound according to claim 6, selected from the compounds of the formulas (6-1) to (29-1),

where the symbols used have the meanings given in claim 1.

8. A compound according to claim 7, selected from the compounds of the formulas (6a-1) to (29b-1),

the symbols used referring to claim 1

Have meanings.

9. Compound according to one or more of claims 1 to 8,

characterized in that Ar ¹ , Ar ² and Ar ³ each occur identically or differently for an aromatic or heteroaromatic ring system with 6 to 24 aromatic ring atoms which can be substituted by one or more radicals R.

10. A compound according to one or more of claims 1 to 9,

characterized in that R is selected identically or differently on each occurrence from the group consisting of H, D, F, N (Ar ') ₂ , CN, OR ¹ , a straight-chain alkyl group with 1 to 10 carbon atoms or an alkenyl group with 2 to 10 carbon atoms or a branched or cyclic alkyl group with 3 to 10 carbon atoms, where the alkyl or alkenyl group can in each case be substituted with one or more radicals R ¹ , and where one or more non-adjacent CH ₂ groups can be replaced by O, or an aromatic or heteroaromatic ring system with 6 to 30 aromatic ring atoms, each of which can be substituted by one or more radicals R ¹ ; two radicals R here can also form a ring system with one another.

11. A formulation containing at least one compound according to one or more of claims 1 to 10 and at least one further compound and / or a solvent.

12. Use of a compound according to one or more of the

Claims 1 to 10 in an electronic device.

13. Electronic device containing at least one connection according to one or more of claims 1 to 10.

14. Electronic device according to claim 13, wherein it is an organic electroluminescent device, thereby marked indicates that the compound according to one or more of claims 1 to 10 in an emitting layer as a matrix material for phosphorescent emitters or for emitters showing TADF (thermally activated delayed fluorescence), and / or in an electron transport layer and / or in a hole blocking layer and / or in a hole transport layer and / or in an exciton blocking layer.