EP4200294A1

EP4200294A1 - Materials for organic electroluminescent devices

Info

Publication number: EP4200294A1
Application number: EP21759302.9A
Authority: EP
Inventors: Amir Hossain Parham; Philipp Stoessel; Christian Ehrenreich
Original assignee: Merck Patent GmbH
Current assignee: Merck Patent GmbH
Priority date: 2020-08-18
Filing date: 2021-08-16
Publication date: 2023-06-28
Also published as: WO2022038065A1; US20240090327A1; KR20230053629A; CN115956074A

Abstract

The invention relates to compounds which are suitable for use in electronic devices, and 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 these materials.

In organic electroluminescent devices (OLEDs), phosphorescent organometallic complexes are frequently used as emitting materials. In general, there is still a need for improvement in OLEDs, in particular also in OLEDs which exhibit 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 also 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 e.g. in WO 2011/116865, WO 2011/137951, WO 2013/064206 or KR 2015-037703.

The object of the present invention is to provide compounds which are suitable for use in an OLED, in particular as a matrix material for phosphorescent emitters or as electron transport materials, and lead to good properties there.

It has surprisingly been found that certain compounds, which are 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, high efficiency and a lower operating voltage. These compounds and electronic devices, in particular organic electroluminescent devices, which contain these compounds are therefore the subject matter of the present invention.

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

Formula (1) where the following applies to the symbols and indices used:

X is the same or different on each occurrence CR or N with the proviso that a maximum of two groups X per cycle represent N, and further provided that two adjacent groups X that are part of the same six-membered ring represent CR, where the adjacent R radicals form an aromatic or heteroaromatic ring system which is fused to the cycle and has 4 to 8 ring atoms, which can be substituted by one or more R radicals;

Y is BR, C(R) ₂ , C=O, Si(R) ₂ , NR, NAr ¹ , O, S, Se, SO, SO ₂ , PR or P(=O)R, where in the case of m or n is 0, the carbon atoms bonding to Y are each X; m and n are 0 or 1, where m + n is 1;

Ar ¹ is an aromatic ring system having 6 to 40 aromatic ring atoms which may be substituted by one or more R ¹ groups, or a heteroaromatic ring system having 5 to 40 aromatic ring atoms which may be substituted by one or more R ¹ groups;

R is the same or different on each occurrence H, D, F, CI, Br, I, N(Ar') ₂ , N(R ¹ ) ₂ , OAr', SAr', B(OR ¹ ) ₂ , CHO, C (=O) ^R1 , ^CR1 =C( ^R1 ) ₂ , CN, C(=O) ^OR1 , C(=O)NR1 , Si( ^R1 ) ³ , Ge( ^R1 ₎₃ _, NO2 , P(=O)(R ¹ ) ₂ , OSO2R ¹ , OR ¹ , S(=O)R ¹ , S(=O)2R ¹ , SR ¹ , a straight-chain alkyl group with 1 to 20 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, where the alkyl, alkenyl or alkynyl group is substituted in each case with one or more radicals R ¹ where one or more non-adjacent CH2 groups are replaced by -R ¹ C=CR ¹ - -S-, SO or SO2 can be replaced, or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, preferably having 5 to 40 aromatic ring atoms, which can each be substituted by one or more radicals R ¹ , with two or more on radicals R bonded to the same cycle can together form an aliphatic, heteroaliphatic, aromatic or heteroaromatic ring system which can be substituted by one or more radicals R ¹ , and where two radicals R bonded to the same carbon or silicon atom are a monocyclic or polycyclic, aliphatic, aromatic or heteroaromatic ring system which can be substituted with one or more radicals R ¹ ;

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

R ¹ is the same or different on each occurrence H, D, F, I, B(OR ² )2, N(R ² ) ₂ , CHO, C(=O)R ² , CR ² =C(R ² ) ₂ , CN, C(=O)OR ² , Si(R ² ) ₃ , NO2, P(=O)(R ² ) ₂ , OSO2R ² , SR ² , OR ² , S(=O)R ² , S( = O) ₂ R ² , a straight-chain alkyl group having 1 to 20 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, the alkyl, alkenyl - or alkynyl group can each be substituted by one or more radicals R ² and one or more CH2 groups in the above groups by -R ² C = CR ² -, -CEC-, Si (R ² ) ₂ , C = O, C=S, -C(=O)O-, NR ² , CONR ² , P(=O)(R ² ), -O-, -S-, SO or SO 2 may be substituted and one or more H atoms in the above groups by D, F, CI, Br, I, CN or NO2 may be replaced, or an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, each of which may be substituted by one or more R ² radicals, where two or more R ¹ radicals together may form an aliphatic, heteroaliphatic, aromatic or heteroaromatic ring system;

R ² is the same or different on each occurrence and is H, D, F, CN or an aliphatic, aromatic or heteroaromatic organic radical having 1 to 20 carbon atoms, in which one or more H atoms can also be replaced by D or F; two or more substituents R ² can be linked to one another and form a ring.

An aryl group within the meaning of this invention contains 6 to 40 carbon atoms; a heteroaryl group within the meaning of this invention contains 2 to 40 carbon atoms and at least one heteroatom, with the proviso that the sum of carbon 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 either a simple aromatic cycle, ie benzene, or a simple heteroaromatic cycle, for example pyridine, pyrimidine, thiophene, etc., or one fused (fused) aryl or heteroaryl group, for example naphthalene, anthracene, phenanthrene, quinoline, isoquinoline, etc. understood. On the other hand, aromatics linked to one another by a single bond, such as biphenyl, are not referred to as aryl or heteroaryl groups, but as aromatic ring systems.

An aromatic ring system within the meaning of this invention contains 6 to 60 carbon atoms, preferably 6 to 40 carbon atoms in the ring system. A heteroaromatic ring system within the meaning of this invention contains 2 to 60 carbon atoms, preferably 2 to 40 carbon atoms and at least one heteroatom in the ring system, with the proviso that the sum of carbon atoms and heteroatoms is at least 5. The heteroatoms are preferably selected from N, O and/or S. An aromatic or heteroaromatic ring system in the context of this invention is to be understood as meaning a system which does not necessarily only contain aryl or heteroaryl groups, but in which also several aryl or heteroaryl groups can be replaced by a non-aromatic moiety, such as e.g. B. a C, N or O atom may be connected. Likewise, systems are to be understood here in which two or more aryl or heteroaryl groups are linked directly to one another, such as, for. B. biphenyl, terphenyl, bipyridine or phenylpyridine. For example, systems such as fluorene, 9,9'-spirobifluorene, 9,9-diarylfluorene, triarylamine, diaryl ether, stilbene, etc. should also be understood as aromatic ring systems for the purposes of this invention, and also systems in which two or more aryl groups, for example connected 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 also fluorene or spirobifluorene.

An electron-rich heteroaromatic ring system is characterized in that it is a heteroaromatic ring system that does not contain any electron-deficient heteroaryl groups. An electron-deficient heteroaryl group is a six-membered-membered heteroaryl group containing at least one nitrogen atom or a five-membered-membered heteroaryl group containing at least two heteroatoms, one of which is a nitrogen atom and the other is oxygen, sulfur or a substituted nitrogen atom, further aryl or heteroaryl groups being attached to each of these groups can be condensed. In contrast, electron-rich heteroaryl groups are five-membered-membered heteroaryl groups with exactly one heteroatom selected from oxygen, sulfur or substituted nitrogen, to which further aryl groups and/or further electron-rich five-membered-membered heteroaryl groups can be fused. Thus, examples of electron-rich heteroaryl groups are pyrrole, furan, thiophene, indole, benzofuran, benzothiophene, carbazole, dibenzofuran, dibenzothiophene or indenocarbazole. An electron-rich heteroaryl group is also referred to as an electron-rich heteroaromatic radical.

An electron-deficient heteroaromatic ring system is characterized in that there is at least one electron-deficient heteroaryl group contains, and particularly preferably no electron-rich heteroaryl groups.

In the context of the present invention, the term alkyl group is used as a generic term both for linear or branched alkyl groups and for cyclic alkyl groups. Analogously, the terms alkenyl group and alkynyl group are used as generic terms both for linear or branched alkenyl or alkynyl groups and for cyclic alkenyl or alkynyl groups.

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 individual H atoms or CH 2 groups are also substituted by the abovementioned groups can be, 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, cycloheptyl, n-octyl, cyclooctyl, 2-ethylhexyl, trifluoromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, ethenyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl or octynyl. An alkoxy group OR ¹ having 1 to 40 carbon atoms is preferably 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 having 1 to 40 carbon atoms is, 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, Understood heptenylthio, cycloheptenylthio, octenylthio, cyclooctenylthio, ethynylthio, propynylthio, butynylthio, pentynylthio, hexynylthio, heptynylthio or octynylthio. In general, alkyl, alkoxy or thioalkyl groups according to of the present invention can be straight-chain, branched or cyclic, it being possible for one or more non-adjacent CH2 groups to be replaced by the groups mentioned above; furthermore, one or more H atoms can also be replaced by D, F, Cl, Br, I, CN or NO2, preferably F, Cl 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 abovementioned R ² radicals or a hydrocarbon radical and which can be linked via any position on the aromatic or heteroaromatic compound, is understood to mean, in particular, groups derived from are of benzene, naphthalene, anthracene, benzanthracene, phenanthrene, pyrene, chrysene, perylene, fluoranthene, naphthacene, pentacene, benzopyrene, biphenyl, biphenylene, terphenyl, triphenylene, fluorene, spiro- bifluorene, dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis- or trans-indenofluorene, cis- or trans-indenocarbazole, cis- or trans-indolocarbazole, truxene, isotruxene, spirotruxene, spiroisotruxene, furan, benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene, isobenzothiophene, dibenzothiophene, pyrrole , indole, isoindole, carbazole, pyridine, quinoline, isoquinoline, acridine, phenanthridine, benzo-5,6-quinoline, benzo-6,7-chi nolin, benzo-7,8-quinoline, phenothiazine, phenoxazine, pyrazole, indazole, imidazole, benzimidazole, naphthimidazole, phenanthrimidazole, pyridimidazole, pyrazineimidazole, quinoxalineimidazole, oxazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, 1 , 2-thiazole, 1,3-thiazole, benzothiazole, pyridazine, hexaazatriphenylene, benzopyridazine, pyrimidine, benzopyrimidine, quinoxaline, 1,5-diazaanthracene, 2,7-diazapyrene, 2,3-diazapyrene, 1,6-diazapyrene, 1, 8-diazapyrene, 4,5-diazapyrene, 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 group pen derived from combining these systems. In the context of the present description, the wording that two or more radicals can form a ring system with one another is to be understood, inter alia, as meaning that the two radicals are linked to one another by a chemical bond with formal splitting off of two hydrogen atoms. This is illustrated by the following scheme:

form

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

In a preferred embodiment, the compound comprises a

Structure of the above formula (1) and formula (2)

Formula (2) where the symbols used have the meanings given above and the following also applies:

X is the same or different on each occurrence CR or N with the proviso that a maximum of two groups X per cycle stand for N, and further with the proviso that two adjacent groups X, which are part of the same cycle, represent C to which a group of formula (2) forms, via the bonds marked *, an aromatic or heteroaromatic ring system fused to the cycle;

Q is the same or different on each occurrence CR ¹ or N, with the proviso that a maximum of two Q groups per cycle are N.

The following formulas (3) and (4) show further preferred embodiments: where the symbols and indices used have the meanings given above for formulas (1) and (2).

In a preferred embodiment of the invention, Y in the preceding and following embodiments represents C(R) 2 , NAr ¹ , O or S, more preferably NAr ¹ , O or S and very particularly preferably NAr ¹ .

In a preferred embodiment, at least one radical R of the symbols Y, X and/or Q in the formulas (3) or (4) is an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, preferably having 5 to 40 aromatic ring atoms and particularly preferably having 6 to 24 aromatic ring atoms, each by a or more radicals R ¹ can be substituted, wherein the radicals R ¹ are preferably non-aromatic.

In a preferred embodiment of the invention, a maximum of one X symbol per cycle stands for N, particularly preferably no X symbol.

In a preferred embodiment of the invention, X and Q are CR.

The following formulas (5) to (8) show further preferred embodiments:

Formula (7) Formula (8) where the symbols used have the meanings given above for formula (2). Preferred embodiments of the compounds of the formulas (5) to (8) are the following compounds of the formulas (5-1) to (8-1):

Formula (7-1) Formula (8-1) where the symbols, if present, have the meanings given for formulas (5) to (8).

In a preferred embodiment of the invention, a maximum of 4 groups R in the formulas (5) to (8), preferably in the formulas (5-1) to (8-1), are not H, CN or D, particularly preferably a maximum of 3 Groups R and very particularly preferably a maximum of two groups R. In a preferred embodiment of the invention, a maximum of 4 groups R in the formulas (5) to (8), preferably in the formulas (5-1) to (8-1), are not H, CN or D, particularly preferably a maximum of 3 Groups R and very particularly preferably a maximum of one group R, in which case R is an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, preferably having 5 to 40 aromatic ring atoms and particularly preferably having 6 to 24 aromatic ring atoms, each of which is substituted by one or more R ¹ radicals may be substituted.

If Y is NAr ¹ , in particular in the formulas (5) to (8), preferably in the formulas (5-1) to (8-1), in a preferred embodiment there is at most one radical R and particularly preferably none R is an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, preferably having 5 to 40 aromatic ring atoms, particularly preferably having 6 to 24 aromatic ring atoms, in particular all R are H, D or CN, preferably H or D, particularly preferably , when Ar ¹ is an electron-deficient heteroaromatic ring system, in particular an electron-deficient heteroaromatic.

If Y is NAr ¹ , where Ar ¹ stands for an aromatic ring system or an electron-rich heteroaromatic ring system, in a preferred embodiment a maximum of 2 radicals R, preferably a maximum of one radical R, stand for an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms , preferably having 5 to 40 aromatic ring atoms, particularly preferably having 6 to 24 aromatic ring atoms, where the two radicals R are not attached to the same cycle.

In a preferred embodiment, if Y is O or S, a maximum of 3 groups R, preferably a maximum of two radicals R, in particular only one radical R, stand for an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, preferably having 5 to 40 aromatic ring atoms , particularly preferably having 6 to 24 aromatic ring atoms, all R radicals being bonded to another ring. The following formulas (5-1 -1) to (8-1 -4) show further preferred embodiments of the formulas (5) to (8):

Formula (5-1-5) Formula (6-1-1)

Formula (8-1-4) where the symbols, if present, have the meanings given for formulas (5) to (8) and the following also applies:

R' is the same or different on each occurrence or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, preferably having 6 to 40 aromatic ring atoms, which can each be substituted by one or more R ¹ groups.

In a preferred embodiment, only up to two further R's in the formulas (5-1-1) to (8-1-4) are identical or different on each occurrence for an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, preferably with 5 to 40 aromatic ring atoms and particularly preferably with 6 to 24 aromatic ring atoms, each of which can be substituted by one or more groups R ¹ .

If Y is NAr ¹ , where Ar ¹ is an aromatic or electron-rich heteroaromatic ring system having 5 to 60 aromatic ring atoms, preferably having 5 to 40 aromatic ring atoms and particularly preferably having 6 to 24 aromatic ring atoms, compounds of the formulas (5- 1 -1 ), (5-1 -2), (5-1 -3), (6-1 -1 ), (6-1 -2), (6-1 -3), (7-1 - 1 ), (7-1 -2), (7-1 -3), (7-1 -4), (8-1 -1 ), (8-1 -2) and (8-1 -3) preferred, with preferably only a maximum of one radical R for an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, preferably having 6 to 40 aromatic ring atoms and particularly preferably having 6 to 24 aromatic ring atoms, where this R does not bind to the same cycle as R '.

If Y is O or S, preferably O, compounds of the formulas (5-1 -1), (5-1 -2), (5-1 -4), (5-1 -5), (6 -1 -1 ), (6-1 -2), (6-1 -4), (7-1 -1 ), (7-1 -2), (7-1 -3), (8-1 -1), (8-1 -2) and (8-1 -4) are preferred, with preferably only a maximum of one radical R standing for an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, preferably having 6 to 40 aromatic ring atoms and particularly preferably with 6 to 24 aromatic ring atoms, this R not attaching to the same cycle as R'.

Preferred substituents R, Ar ¹ , Ar', R ¹ and R ² are described below. In a particularly preferred embodiment of the invention, the preferences given below for R, Ar ¹ , Ar′, R ¹ and R ² occur simultaneously and apply to the structures of the formula (1) and to all preferred embodiments listed above.

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

Suitable aromatic or heteroaromatic ring systems Ar ¹ are selected identically or differently on each occurrence from phenyl, biphenyl, in particular ortho-, meta- or para-biphenyl, terphenyl, in particular ortho-, meta-, para- or branched terphenyl, and quaterphenyl , In particular ortho-, meta-, para- or branched quaterphenyl, fluorene, which can be linked via the 1-, 2-, 3- or 4-position, spirobifluorene, which via the 1-, 2-, 3- or 4-position, naphthalene, which can be linked via the 1- or 2-position, indole, benzofuran, benzothiophene, dibenzofuran, carbazole, which can be linked via the 1-, 2-, 3- or 4-position can, dibenzofuran, which can be linked via the 1-, 2-, 3- or 4-position, dibenzo-thiophene, which can be linked via the 1-, 2-, 3- or 4-position, indenocarbazole, indolocarbazole, Phenanthrene, triphenylene or a combination of two or three of these groups, each with one ode r several radicals R ¹ , preferably non-aromatic radicals R ¹ can be substituted. Further preferred embodiments for Ar ¹ when they represent a heteroaromatic ring system are selected from the group consisting of pyridine, pyrimidine, pyrazine, pyridazine, triazine, quinoline, quinazoline, quinoxaline or benzimidazole or a combination of these groups with one of the groups mentioned above, each of which may be substituted by one or more R ¹ radicals. If Ar ¹ is a heteroaryl group, in particular triazine, pyrimidine, quinazoline or quinoxaline, preference may also be given to aromatic or heteroaromatic radicals R ¹ on this heteroaryl group.

In a preferred embodiment of the invention, R is selected identically or differently on each occurrence from the group consisting of H, D, F, CN, OR ¹ , a straight-chain alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon Atoms or a branched or cyclic alkyl group having 3 to 10 carbon atoms, where the alkyl or alkenyl group may be substituted by one or more radicals R ¹ , but is preferably unsubstituted, and where one or more non-adjacent CH2 groups by O can be replaced, or an aromatic or heteroaromatic ring system having 6 to 30 aromatic ring atoms, which can each be substituted by one or more radicals R ¹ ; two radicals R 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, a straight-chain alkyl group having 1 to 6 carbon atoms, in particular having 1, 2, 3 or 4 carbon atoms, or a branched or cyclic alkyl group having 3 up to 6 carbon atoms, where the alkyl group can be substituted by one or more radicals R ¹ , but is preferably unsubstituted, or an aromatic or heteroaromatic ring system having 6 to 24 aromatic ring atoms, each of which is substituted by one or more radicals R ¹ , preferably non-aromatic radicals R ¹ may be substituted. R is very particularly preferably selected on each occurrence, identically or differently, from the group consisting of H or an aromatic or heteroaromatic ring system having 6 to 24 aromatic ring atoms, which can be substituted by one or more radicals R ² , preferably non-aromatic radicals R ¹ . Suitable aromatic or heteroaromatic ring systems R are 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, 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, which can be linked via the 1-, 2-, 3- or 4-position, dibenzofuran, carbazole, 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 may be substituted by one or more R ¹ radicals. If R is a heteroaryl group, in particular triazine, pyrimidine or quinazoline, preference may also be given to aromatic or heteroaromatic radicals R ¹ on this heteroaryl group.

The groups R or Ar ¹ , if they stand for an aromatic or heteroaromatic ring system, are preferably selected from the groups of the following formulas R-1 to R-82,

where R ¹ has the meanings given above, the dashed bond represents the bond to a carbon atom of the basic structure in formula (1) or in the preferred embodiments, or to a heteroatom of the group N(Ar')2 or NR2 and continues to apply :

Ar ³ is identical or different on each occurrence, a bivalent aromatic or heteroaromatic ring system having 6 to 18 aromatic ring atoms, which can be substituted by one or more radicals R ¹ ;

A ¹ is identical or different on each occurrence, C(R ¹ ) 2 , NR ¹ , 0 or S, preferably 0 or S; p is 0 or 1, where m = 0 means that the group Ar ³ is not present and that the corresponding aromatic or heteroaromatic group is attached directly to a carbon atom of the basic structure in formula (1) or in the preferred embodiments or to that nitrogen atom is attached in the group N(Ar ¹ )2; provided that m = 1 for structures R-12, R-17, R-21, R-25, R-26, R-30, R-34, R-38, R-39 and R- 67 when these groups are embodiments of Ar ¹ ; r is 0 or 1, where r=0 means that no group A is bonded to this position and radicals R ¹ are bonded to the corresponding carbon atoms instead;

In a preferred embodiment, Ar ³ comprises divalent aromatic or heteroaromatic ring systems based on the groups of R-1 to R-82, where m is 0 and the dashed bond and an R ¹ for the bond to the aromatic or heteroaromatic group after R-1 until R-82 stands.

If the groups R-1 to R-82 mentioned above have several groups A ¹ for R or Ar ¹ , then all combinations from the definition of A ¹ are suitable for this. Preferred embodiments are then those in which one group A ¹ is 0 or S and the other group A ¹ is C(R ¹ ) ₂ or in which both groups A ¹ are S or 0 or in which both groups A ¹ are 0 or S.

If A ¹ is NR ¹ , the substituent R ¹ which is bonded to the nitrogen atom is preferably an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms, which can also be substituted by one or more R ² radicals. In a particularly preferred embodiment, this substituent R ¹ is identical or different on each occurrence for an aromatic or heteroaromatic ring system having 6 to 24 aromatic ring atoms, preferably having 6 to 12 aromatic ring atoms, which has no fused aryl groups or heteroaryl groups in which two or more aromatic or heteroaromatic 6-ring groups are fused directly to one another, and which can each also be substituted by one or more R ² radicals. Particular preference is given to phenyl, biphenyl, terphenyl and quaterphenyl with linkage patterns as listed above for R-1 to R-11, it being possible for these structures to be substituted by one or more radicals R ¹ , but they are preferably unsubstituted.

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

If Y is CR2, the substituents R bonded to this carbon atom are preferably identical or different on each occurrence for a linear alkyl group having 1 to 10 carbon atoms or for a branched or cyclic alkyl group having 3 to 10 carbon atoms or for an aromatic or electron-poor heteroaromatic ring system having 5 to 24 aromatic ring atoms, which can also be substituted by one or more R ¹ radicals. Very particularly preferably, these substituents R are a methyl group or a phenyl group. The radicals R can also form a ring system with one another, which leads to a spiro system.

In one embodiment of the invention, at least one radical R or Ar ¹ represents 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, with 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 is NR ¹ , where R ¹ is preferably an aromatic or heteroaromatic ring system, in particular an aromatic ring system.

In a further particularly preferred embodiment of the invention, at least one radical R or Ar ¹ 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, R-76 shown above; R-79, R-80, R-81 and R-82.

In a further preferred embodiment of the invention, R ¹ is the same or different on each occurrence selected from the group consisting of H, D, F, CN, OR ² , a straight-chain alkyl group with 1 bis 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms or a branched or cyclic alkyl group having 3 to 10 carbon atoms, wherein the alkyl or alkenyl group may be substituted with one or more radicals R ² and wherein one or several non-adjacent CH2 groups can be replaced by O, or an aromatic or heteroaromatic ring system having 6 to 30 aromatic ring atoms, which can each be substituted by one or more radicals R ² ; two or more radicals R ¹ can form an aliphatic ring system with one another. In a particularly preferred embodiment of the invention, R ¹ is identical or different on each occurrence selected from the group consisting of H, a straight-chain alkyl group having 1 to 6 carbon atoms, in particular having 1, 2, 3 or 4 carbon atoms, or one branched or cyclic alkyl group having 3 to 6 carbon atoms, where the alkyl group may be substituted by one or more radicals R ² , but is preferably unsubstituted, or an aromatic or heteroaromatic ring system having 6 to 24 aromatic ring atoms, each of which is substituted by one or more R ² radicals may be substituted, but is preferably unsubstituted.

In a further preferred embodiment of the invention, R ² is the same or different on each occurrence of H, F, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms which is linked to an alkyl group having 1 to 4 carbon atoms. Atoms may be substituted, but is preferably unsubstituted.

In a further preferred embodiment of the invention, all radicals R ¹ , if they represent an aromatic or heteroaromatic ring system, or R ² if they represent aromatic or heteroaromatic groups, are selected from the groups R-1 to R-82, which, however, then are each substituted with R ² or with the groups mentioned for R ² instead of with R ¹ .

In a preferred embodiment, apart from the group of the formula (2), the radicals R do not form any further aromatic or heteroaromatic groups fused onto the basic structure of the formula (1). 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, are also compounds that are substituted with alkyl groups, especially branched alkyl groups, having up to 10 carbon atoms or with oligoarylene groups, such as ortho-, meta-, para- or branched terphenyl or quaterphenyl groups are substituted.

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

The preferred embodiments mentioned above can be combined with one another at will within the limitations defined in claim 1. In a particularly preferred embodiment of the invention, the preferences mentioned above occur simultaneously.

Examples of preferred 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 can be represented by the routes outlined in schemes 1, 2 and 3. Schemes 1 and 2 show the synthesis of the compounds in which Y is NAr ¹ while in Scheme 3 Y is 0.

Scheme 1 :

a,b,c = 0 or 1

The compounds according to the invention can be prepared by synthesis steps known to those skilled in the art, such as, for. B. bromination, Suzuki coupling, Ullmann coupling, Hartwig-Buchwald coupling, etc., are shown. In Scheme 1, 2 and 3, L is a divalent aromatic or heteroaromatic ring system and Ar is an aromatic or heteroaromatic ring system.

Formulations of the compounds according to the invention are required for the processing of the compounds according to the invention from the liquid phase, for example by spin coating or by printing processes. These formulations can be, for example, solutions, dispersions or emulsions. Mixtures of this may be preferred using two or more solvents. Suitable and preferred solvents are, for example, toluene, anisole, o-, m- or p-xylene, methyl benzoate, mesitylene, tetralin, veratrol, 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 -dimethylanisole, 3,5-dimethylanisole, acetophenone, a-terpineol, benzothiazole, butyl benzoate, cumene, cyclohexanol, cyclohexanone, cyclohexylbenzene, decalin, dodecylbenzene, ethyl benzoate, indane, NMP, p-cymene, phenetole, 1,4 -Diisopropylbenzene, dibenzyl ether, diethylene glycol butyl methyl ether, triethylene glycol butyl methyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, diethylene glycol monobutyl ether, tripropylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 2-isopropylnaphthalene, pentylbenzene, hexylbenzene, heptylbenzene, octylbenzene, 1,1-bis(3,4-dimethylphen yl)ethane, 2-methylbiphenyl, 3-methylbiphenyl, 1-methylnaphthalene, 1-ethylnaphthalene, ethyl octanoate, sebacic acid diethyl ester, octyl octanoate, heptylbenzene, menthyl isovalerate, cyclohexyl hexanoate or mixtures of these solvents.

A further object of the present invention is therefore a formulation containing at least one compound according to the invention and at least one further compound. The further compound can be a solvent, for example, in particular one of the abovementioned solvents or a mixture of these solvents. However, the further compound can 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 electroluminescent device. This further connection can also be polymeric.

The compounds according to the invention are suitable for use in an electronic device, in particular in an organic electroluminescent device. A further subject matter 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 connection 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. In this case, the component can also contain inorganic materials or also layers which are made up 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 -Laser) and "organic plasmon emitting devices", but preferably organic electroluminescent devices (OLEDs), particularly preferably phosphorescent OLEDs.

The organic electroluminescent device contains 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. as well Interlayers can be introduced between two emitting layers, which have an exciton-blocking function, for example. However, it should be pointed out that each of these layers does not necessarily have to be present. In this case, the organic electroluminescence device can contain an emitting layer, or it can contain a plurality of emitting layers. If a plurality of emission layers are present, these preferably have a total of a plurality of emission maxima between 380 nm and 750 nm, resulting overall in white emission, ie different emitting compounds which can fluoresce or phosphorescence are used in the emitting layers. Systems with three emitting layers are particularly preferred, with the three layers showing blue, green and orange or red emission. The organic electroluminescence device according to the invention can also be a tandem OLED, in particular for white-emitting OLEDs.

The connection 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 electroluminescence device containing a compound of the formula (1) or the preferred embodiments outlined above in an emitting layer as matrix material for phosphorescent emitters or for emitters which exhibit 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, with at least one emitting layer containing at least one compound according to the invention as 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). under phosphorescence within the meaning of this invention, the luminescence is understood to be from an excited state with a higher spin multiplicity, ie 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 indium, platinum and copper complexes, are to be regarded as phosphorescent compounds.

The mixture of the compound according to the invention and 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.

A further 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 a further 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, z. CBP (N,N-biscarbazolylbiphenyl) or 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, z. 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, z. B. according to WO 2007/137725, silanes, z. B. according to WO 2005/111172, azaborole or boron ester, z. B. according to WO 2006/117052, triazine derivatives, z. 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, z. B. according to WO 2010/054730, bridged carbazole derivatives, z. B. according to WO 2011/042107, WO 2011/060867, WO 2011/088877 and WO 2012/143080, triphenylene derivatives, z. B. according to WO 2012/048781, or dibenzofuran derivatives, z. according to WO 2015/169412, WO 2016/015810, WO 2016/023608, WO 2017/148564 or WO 2017/148565. Likewise, another phosphorescent emitter, which emits at a shorter wavelength than the actual emitter, can 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 charge transport, as described, for example, in WO 2010/108579.

In a preferred embodiment of the invention, the materials are used in combination with another matrix material. Preferred co-matrix materials, especially when the compound of the invention is substituted with an electron-deficient heteroaromatic ring system, are selected from the group consisting of biscarbazoles, bridged carbazoles, triarylamines, dibenzofuran-carbazole derivatives or dibenzofuran-amine derivatives and the carbazolamines.

Preferred biscarbazoles are the structures of the following formulas (9) and (10),

Formula (9) where the following applies to Ar, R and A ¹ :

A ¹ is the same or different on each occurrence NAr ² , O, S or C(R) ₂ ;

Each time Ar is identical or different, it is an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which can be substituted by one or more R radicals;

R is the same or different on each occurrence: H, D, F, CI, Br, I, B(OR ¹ ) ₂ , CHO, C(=O)R ¹ , CR ¹ =C(R ¹ ) ₂ , CN, C (=O) ^OR1 , C(=O)N(R1 ⁾ ² , Si(R1 ₎₃ ^, N(R1 ₎₂ ^, NO2 , P(=O)(R1 ₎₂ _, ^OSO2R1 , OR ¹ , S(=O)R ¹ , S(=O) ₂ R ¹ , SR ¹ , a straight-chain alkylalkyl group having 1 to 20 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic one Alkyl group with 3 to 20 carbon atoms, where the alkyl, alkenyl or alkynyl group can each be substituted with one or more radicals R ¹ , where one or more non-adjacent CH2 groups are replaced by -R ¹ C=CR ¹ -, - C=C-, Si(R1 ) ² , C=O, C=S, C= ^NR1 , -C(=O)O-, -C(=O) ^NR1 -, ^NR1 , P(= O) (R ¹ ), -O-, -S-, SO or SO2 can be replaced, or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, preferably having 5 to 40 aromatic ring atoms, each replaced by one or more radicals R ¹ may be substituted, where two or more R's can be linked together and form a ring;

In a preferred embodiment of the invention, A ¹ is CR2.

In the case of the formulas (9) and (10), Ar preferably represents an aromatic or heteroaromatic ring system, preferably selected identically or differently on each occurrence from the groups of the following formulas Ar-1 to Ar-82,

where the dashed line represents the bond to the backbone and still holds:

Ar ³ is identical or different on each occurrence, a divalent aromatic or heteroaromatic ring system having 6 to 18 aromatic ring atoms, which can be substituted by one or more radicals R;

Ar ² is an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, which may be substituted with one or more R radicals;

A ¹ is the same or different on each occurrence NAr ² , O, S or C(R) ₂ ; n is 0 or 1, where n=0 means that no group A ¹ is bonded to this position and radicals R are bonded to the corresponding carbon atoms instead; m is 0 or 1, where m=0 means that the group Ar ³ is not present and that the corresponding aromatic or heteroaromatic group is bonded directly to the nitrogen atom. Preferred embodiments of the compounds of the formulas (9) or

(10) are the compounds of the following formulas (9a) or (10a), where the symbols used have the meanings given above according to formula (9) and formula (10).

Examples of suitable compounds of the formula (9) or (10) are the compounds shown below. Preferred bridged carbazoles are the structures of the following formula (11), where A ¹ and R have the meanings given above according to the formulas (9) and (10) and A ¹ is preferably selected identically or differently on each occurrence from the group consisting of NAr and CR2.

Preferred dibenzofuran derivatives are the compounds of the following formula (12), where the oxygen can also be replaced by sulfur, so that a dibenzothiophene is formed, L is a single bond or an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, which can also be substituted by one or more radicals R, and R and Ar are the have the meanings mentioned above. The two groups Ar that bind to the same nitrogen atom, or a group Ar and a group L that bind to the same Bond nitrogen atom can also be connected to each other, for example to form a carbazole.

Examples of suitable dibenzofuran derivatives are the compounds shown below.

Preferred carbazole amines have the structures of the following formulas

(13), (14) and (15), where L is an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, which with one or more R radicals can be substituted, and R and Ar have the meanings given above according to formula (9) or formula (10).

Examples of suitable carbazolamine derivatives are the compounds shown below.

Further particularly preferred co-matrix materials, in particular hole-transporting co-hosts, in particular when the compound according to the invention is substituted with an electron-deficient heteroaromatic ring system, are shown in the following table:

Preferred co-matrix materials, especially when the compound of the invention is substituted with an electron-rich heteroaromatic ring system, for example a carbazole group, are further 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 (16), (17), (18) and (19),

Formula (18) Formula (19) where Ar and R have the meanings given above according to the formulas (9) and (10).

The triazine derivatives of the formula (16) and the quinaxoline derivatives of the formula (19), in particular the triazine derivatives of the formula (16), are particularly preferred.

In a preferred embodiment of the invention Ar in the formulas (16), (17), (18) and (19) is identical or different on each occurrence, an aromatic or heteroaromatic ring system having 6 to 30 aromatic ring atoms, in particular having 6 to 24 aromatic ring atoms Ring atoms which may be substituted by one or more R radicals. Suitable aromatic or heteroaromatic ring systems Ar are the same as those listed above as embodiments for Ar, in particular the structures Ar-1 to Ar-82.

Examples of suitable triazine and pyrimidine 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 and quinoxaline compounds are the compounds shown in the table below:

35

Particularly suitable phosphorescent compounds (= triplet emitters) are compounds which, when suitably excited, 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. in particular 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 phosphorescence emitters, in particular compounds containing iridium or platinum.

Examples of the emitters described above can be found in 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 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, WO 2018/041769, WO 2019/020538, WO 1.78018/ WO 1.78018/ 2019/115423 and WO 2019/158453. In general, all phosphorescent complexes are suitable as are used according to the prior art for phosphorescent OLEDs and as are known to the person skilled in the field of organic electroluminescence, and the person skilled in the art can use further phosphorescent complexes without any inventive step.

Examples of phosphorescent dopants are listed below.

In the further layers of the organic electroluminescent device according to the invention it is possible to use all materials that are customarily used in accordance with 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 of the formula (1) or the preferred embodiments set out above without any inventive step.

Also preferred is an organic electroluminescence device, characterized in that one or more layers are coated using a sublimation process. The materials in vacuum sublimation systems become smaller at an initial pressure 10' ⁵ mbar, preferably less than 10' ⁶ mbar vapor-deposited. 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 also preferred, characterized in that one or more layers are coated using the OVPD (organic vapor phase deposition) method or with the aid of carrier gas sublimation. The materials are applied at a pressure of 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 method, such as. B. screen printing, flexographic printing, offset printing, LITI (Light Induced Thermal Imaging, thermal transfer printing), ink-jet printing (ink jet printing) or nozzle printing. This requires soluble compounds, which are 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 further layers are vapor-deposited.

These methods are generally known to the person skilled in the art and can be applied to organic electroluminescent 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 properties: 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, in particular to a high EQE. This applies in particular when the compounds are used as matrix material for a phosphorescent emitter.

3. The connections according to the invention result in low operating voltages. This applies in particular when the compounds are used as matrix material for a phosphorescent emitter.

The invention is explained in more detail by the examples below, without intending to limit it thereby. From the descriptions, the person skilled in the art can carry out the invention in the entire disclosed range and produce further compounds according to the invention without any inventive step and use these in electronic devices or apply the method according to the invention.

examples

Unless otherwise stated, the following syntheses are carried out under a protective gas atmosphere in dried solvents. The solvents and reagents can e.g. B. from Sigma-ALDRICH or ABCR. The respective information in square brackets or the numbers given for individual compounds relate to the CAS numbers of the compounds known from the literature.

Presentation of the synthons: Trifluoromethanesulfonic acid (73 g, 482 mmol) is added to a solution of 2-iodo-1,1'biphenyl (45 g, 160 mmol) and 3-chlorobenzoic acid (55.5 g, 241 mmol) in DCM (700 mL) over a period of added dropwise at 0°C for 30 min. The reaction is then allowed to warm to room temperature, stirred for one hour and then the reaction mixture is concentrated. MTBE is added to the residue (300 mL) and the mixture is stirred at room temperature for 1 h. The solid is filtered off and washed with MTBE (3×50 mL) and dried in a vacuum drying cabinet. Yield: 56.4 g (131 mmol, 82%), 96% according to NMR.

Under an inert atmosphere, 3-amino-1-chloro-2-naphthalene-carboxylic acid (11.59 g, 52.3 mmol) [CAS-1823470-44-5], S1 a (56.4 g, 131 mmol), K2CO3, (16.00 g, 115.9 mmol) and NMP (350 ml) were placed in a sealed 1 L flask. Pd(OAc)2 (350 mg, 1.66 mmol) is then added and the reaction mixture is stirred at 145° C. for 17 h. After cooling, the reaction is worked up extractively with ethyl acetate and water. The combined organic phases are washed 3 times with water (200 mL each) and 2 times with sat. NaCI solution (100 mL each), dried over Na2SÜ4 and the solvent spun off on a rotary evaporator. The crude product is further purified by column chromatography. Yield: 3.8 g (13 mmol, 25%), purity 95% according to ¹ H-NMR. The compound S2b can be prepared analogously to the procedure described for synthon S2a, starting from 1-amino-3-chloro-naphthalene-2-carboxylic acid and S1a. Yield: 21%

S3a:

2-Bromo-1-chloro-3-nitrobenzene (23.6 g, 100 mmol)[CAS-19 (1-naphthyl]phenyl]boronic acid (24.8 g, 100 mmol) [CAS- and sodium carbonate (21.2 g, 200 mmol) are placed in toluene (700 mL) and water (150 mL) under an inert atmosphere. Tetrakis(triphenylphosphine)palladium(0) (2.32 g, 2.00 mmol) is then added and the reaction mixture is stirred under reflux for 16 h. After cooling, the reaction mixture is filtered off with toluene and Celite through a frit and then worked up by extraction with toluene and water. The organic phase is washed with water (200 mL) and sat. Washed with NaCl solution (100 mL), dried over Na2SÜ4 and the solvent removed on a rotary evaporator. The crude product is recrystallized from ethanol. Yield: 21.6 g (60 mmol, 60%), purity 96% according to ¹ H-NMR.

S3b:

The connection S3b can be produced analogously to the procedure described for synthon S3a. B-[2-(2-naphthyl)phenyl]boronic acid is used instead of B-[2-(1-naphthyl)phenyl]boronic acid Yield: 55%

The compound S3c can be analogous to that described for synthon S3a

Procedure starting from 2-bromo-3-chloro-6-methoxy-nitrobenzene

[1698810-56-8] and B-[2-(1-naphthyl]phenyl]boronic acid Yield: 46% mmol) and potassium carbonate (41.5 g, 300 mmol) are placed in dimethylacetamide (400 mL) under an inert atmosphere. Palladium acetate (674 mg, 3.00 mmol) and 1,3-bis-(2,6-diisopropyl-phenyl)-3H-imidazol-1-ium chloride (2.55 g, 6.00 mmol) [CAS-250285-32- 6] was added and the reaction mixture was stirred at 145 °C for 24 h. After cooling, most of the DMAc is spun off and the batch is worked up by extraction with toluene (600 mL) and water. The aqueous phase is extracted twice with toluene (250 mL each). The combined organic phases are then washed twice with water (300 mL each) and sat. NaCI solution (150 mL), dried over Na2SO4 and the filtrate evaporated. 400 mL n-heptane are added to the crude product and the mixture is stirred at room temperature for 30 min. The solid is then filtered off with suction, washed with n-heptane and dried in a vacuum drying cabinet. Yield: 10.1 g (31.2 mmol, 52%), purity 95% according to ¹ H NMR.

The connection S4b can be established analogously to the procedure described for synthon S4a starting from S3b. Yield: 32%

The connection S4c can be established analogously to the procedure described for synthon S4a starting from S3c. Yield: 49% 44.4 mmol) in 150 mL ethanol to 1 g hydrogenated at 3 bar hydrogen pressure for 36 hours. The reaction mixture is filtered twice over a bed of celite. The filtrate is spun in and the solid obtained is recrystallized from toluene.

Yield: 10.7 g (36.6 mmol, 82%), purity 97% according to ¹ H-NMR

The connection S5b can be established analogously to the procedure described for synthon S5a starting from S4b. Yield: 87%

The connection S5c can be established analogously to the procedure described for synthon S5a starting from S4c. Yield: 62%

S2a (3.8 g, 13.0 mmol), pivalic acid (2.66 g, 26.0 mmol), Cu(0Ac)2 [CAS- 142-71-2] (485 mg, 2.67 mmol), [Cp*lrCl ₂ ]2 [CAS- 12354-84-6] (426 mg, 0.53 mmol) and NMP (100 mL) are placed in a flask. Air is passed through the reaction mixture with a needle and the reaction is stirred at 120° C. for 50 min. After cooling, the NMP is distilled off and the residue is further purified by column chromatography. Yield: 3.1 g (10.5 mmol, 81%), purity 98% according to ¹ H-NMR.

Analogously to S6a, connection S6b can be established starting from S5a. Yield: 72%

Analogously to S6a, connection S6c can be established starting from S5b. Yield: 76%

Analogously to S6a, connection S6d can be established starting from S2b. Yield: 44%

Analogously to S6a, connection S6e can be established starting from S5c. Yield 36%

DMSO (100 mL), K3PO4 (106.15 g, 500 mmol), pyridine-2-carboxylic acid (3.06 g, 24.87 mmol) and Cul (2.37 g, 12.44 mmol) are placed under an inert atmosphere. Then 3-chloro-5-methoxyphenol (45.57 g, 300 mmol) [65262-96-6] and 3-bromo-1-chlorophthalene (60.38 g, 250 mmol) [325956-47-6] are slowly added one after the other and the Reaction mixture stirred at 85°C for 16 h. After cooling, the reaction mixture is worked up by extraction with aqueous ammonia solution and methyl tert-butyl ether. The organic phase is washed 5 times with water and 2 times with sat. Washed with NaCl solution, dried the combined phases over Na2SO4 and removed the solvent on a rotary evaporator. The crude product is further purified by fractional distillation. Yield: 64.64 g (202 mmol) 81% purity 95% according to ¹ H-NMR.

The following connections can be represented analogously. In addition to distillation, column chromatography can be used for purification, or other common solvents such as ethanol, butanol, acetone, ethyl acetate, acetonitrile, toluene, xylene, dichloromethane, methanol, tetrahydrofuran, n-butyl acetate, 1,4-dioxane, dimethyl sulfoxide, N,N -dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, etc. can be used.

S7a (159.6 g, 500 mmol) is placed in THF (750 mL) under an inert atmosphere and cooled to -75.degree. n-Butyllithium (2.5 mol/L in hexane, 400 mL, 1.00 mol) is then slowly added dropwise in such a way that the internal temperature does not exceed -65.degree. Stirring is continued for 4 h at -75 °C and then bromine (28.0 mL, 546.5 mmol) is added dropwise so that the internal temperature does not exceed -65 °C. After the addition is complete, the mixture is stirred at −75° C. for 1 h, then slowly warmed up to 10° C. over the course of 1 h and stirred at 10° C. for 1 h. It is then cooled to 0° C. and the batch is washed with sat. Na2SOs solution (250 mL) carefully quenched. The batch is worked up extractively with toluene and water, the combined organic phases 3 times with water and 1 time with sat. Washed NaCl solution, dried over Na2SÜ4 and removed the solvent on a rotary evaporator. The crude product is stirred 3 times with 2-propanol under reflux. The product is reacted further as an isomer mixture. Yield: 133.8 g (370 mmol, 74%) Purity 95% according to ¹ H-NMR.

The following connections can be represented analogously. In addition to stirring, purification can also be carried out by distillation or column chromatography, or other common solvents such as ethanol, butanol, acetone, ethyl acetate, acetonitrile, toluene, xylene, dichloromethane, methanol, tetrahydrofuran, n-butyl acetate, 1,4-dioxane, dimethyl sulfoxide, N, N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, etc. can be used.

S8d (139.0 mmol), B-(6-methoxy-2-naphthyl)-boronic acid (31.21 g, 154.5 mmol) [156641-98-4] and K2CO3 (38.84 g, 281.0 mmol) are dissolved in THF (720 mL) and Water (180 mL) submitted and rendered inert for 30 min. Tetrakis(triphenylphosphine)palladium [14221 -01 -3] (1.78 g, 1.54 mmol) is then added, and the reaction mixture is stirred under reflux for 16 h. The batch is worked up by extraction with toluene and water, and the combined organic phases are washed with water and sat. Washed NaCl solution, dried over Na2SO4 and removed the solvent on a rotary evaporator. The crude product is recrystallized from ethyl acetate. Yield: 35.8 g, (100 mmol, 72%), 97% according to 1H-NMR. The following connections can be represented analogously. Column chromatography can be used for purification or other common solvents such as ethanol, butanol, acetone, ethyl acetate, acetonitrile, toluene, xylene, dichloromethane, methanol, tetrahydrofuran, n-butyl acetate, 1,4-dioxane, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, etc. can be used.

S9b (35.08 g, 100 mmol) and K2CO3 (41.37 g, 299.3 mmol) are placed under an inert atmosphere, treated with DMAc (500 mL) and rendered inert for 30 min. Then Pd(OAc)2 (447 mg, 1.99 mmol) and 1,3-bis(2,6-diisopropylphenyl)3-/-/-imidazol-1-ium chloride (1.69 g, 3.98 mmol) are added and the reaction mixture was stirred at 155° C. for 16 h. After cooling, the batch is poured into ethanol/water (1:1, 800 mL) and stirred for a further 30 min. The precipitated solid is filtered off and washed 5 times with water and 3 times with ethanol. The crude product is stirred under reflux with 2-propanol. Yield: 26.4 g (82 mmol, 82%), 97% according to 1 H-NMR.

The following connections can be represented analogously. Column chromatography can be used for purification or other common solvents such as ethanol, butanol, acetone, ethyl acetate, acetonitrile, toluene, xylene, dichloromethane, methanol, tetrahydrofuran, n-butyl acetate, 1,4-dioxane, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, etc. can be used

 chloromethane (650 mL) and cooled to 0 °C in an ice bath. BBrs (6.0 mL 63.2 mmol) is then carefully added dropwise. After the addition is complete, the batch is allowed to warm to room temperature. After the reaction is complete, the mixture is cooled again to 0° C. and carefully quenched with MeOH (200 mL). The solvent is drawn off on a rotary evaporator. The mixture is then treated 3 times with 300 mL MeOH each time and this is then drawn off on a rotary evaporator. Another 200 mL MeOH are added and the solid is filtered off with suction. The raw product is dried and used in the next step. Yield 19.4 g (63 mmol, 63%).

The following connections can be represented analogously. Column chromatography can be used for purification or other common solvents such as ethanol, butanol, acetone, ethyl acetate, acetonitrile, toluene, xylene, dichloromethane, methanol, tetrahydrofuran, n-butyl acetate, 1,4-dioxane, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, etc. can be used.

S11a (13.95 g, 45.3 mmol) and triethylamine (18.8 mL, 135.9 mmol) are placed in dichloromethane (650 mL) and cooled to 0 °C in an ice bath. Then trifluoromethanesulfonic acid anhydride (9.9 mL, 58.9 mmol) slowly added dropwise. After the addition is complete, the batch is allowed to warm to room temperature. After the reaction is complete, the batch is worked up by extraction with dichloromethane and water, and the combined org. Phases dried over Na2SO4 and the solvent removed on a rotary evaporator. The residue is taken up in 400 mL cyclohexane and stirred at room temperature for 30 min. The solid is filtered off with suction and dried in a vacuum drying cabinet. Yield 14.95 g, (34.0 mmol, 75%)

The following connections can be represented analogously. Column chromatography can be used for purification or other common solvents such as ethanol, butanol, acetone, ethyl acetate, acetonitrile, toluene, xylene, dichloromethane, methanol, tetrahydrofuran, n-butyl acetate, 1,4-dioxane, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, etc. can be used. 30.2 mmol), bis(pinacolato)diboron (9.40 g, 36.3 mmol) and KOAc (8.90 g, 90.68 mmol) are placed in 1,4-dioxane (250 mL) and rendered inert for 30 min. Then Pd(dppf)Cl2 (740 mg, 0.91 mmol) is added and the following compounds can be prepared analogously. Alternatively, Pd(PCy3)2Cl2 or Pd2(dba)3 with S-Phos (1:3) can also be used as the catalyst system. In addition to column chromatography, hot extraction can also be used for purification, and hot extraction can be used for recrystallization other common solvents such as ethanol, butanol, acetone, ethyl acetate, acetonitrile, toluene, xylene, dichloromethane, methanol, tetrahydrofuran, n-butyl acetate, 1,4-dioxane or, for recrystallization, high boilers such as dimethyl sulfoxide, N,N-dimethylformamide, N,N- dimethylacetamide, N-methylpyrrolidone, etc. can be used.

S14:

S6e (32.1 g, 100 mmol), bromobenzene (17.3 g, 110 mmol) and sodium tert-butanolate (20.18 g, 210 mmol) are placed in toluene (800 mL). XPhos Pd G3 [CAS-1445085-55-1] (3.40 g, 4.6 mmol) is then added and the reaction solution is heated to boiling for 24 h. The reaction solution is allowed to cool to room temperature. The reaction mixture is worked up by extraction with toluene and water. The combined organic phases are dried over Na2SÜ4 and the solvent is drawn off on a rotary evaporator. The crude product is recrystallized from n-butyl acetate. Yield: 18.0 g (87 mmol, 87%); Purity: 98% according to ¹ H-NMR.

Presentation of the compounds according to the invention

Synthesis of P1a:

S6a (8.30 g, 28.5 mmol), 2-chloro-4,6-diphenyl-1,3,5-triazine (8.40 g, 31.3 mmol) [CAS-3842-55-5] and sodium tert-butanolate (3.00 g, 31.3 mmol) are placed in toluene (250 mL). Then XPhos Pd G3 [CAS-1445085-55-1] (2.10 g, 2.8 mmol) is added and the reaction solution is heated to boiling for 72 h. The reaction solution is cooled to room temperature and the solvent is removed on a rotary evaporator. The crude product is purified by column chromatography (n-heptane/ethyl acetate) and then recrystallized four times n-Butyl acetate and sublimation purified under high vacuum. Yield:

7.9g (15.1mmol, 53%); Purity > 99.9% according to HPLC.

The following connections can be represented analogously. In addition to column chromatography, hot extraction can also be used for purification, and other common solvents such as ethanol, butanol, acetone, ethyl acetate, acetonitrile, toluene, xylene, dichloromethane, methanol, tetrahydrofuran, n-butyl acetate, 1,4-dioxane or for recrystallization or hot extraction can be used Recrystallization of high boilers such as dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, etc. can be used. 5

30

35

P2a:

S6a (17.92 g, 61.5 mmol), 2-(3-bromophenyl)-4,6-diphenyl-1,3,5-triazine [CAS-864377-31-1] (25.2 g, 65.0 mmol) and sodium tert -butoxide (13.4 g, 139.1 mmol) are placed in o-xylene (550 mL). Then XPhos Pd G3 (1.70 g, 2.3 mmol) is added and the reaction solution is heated to boiling for 24 h. The reaction solution is allowed to cool to room temperature, and the precipitated solid is filtered off with suction and washed 3 times with ethanol (150 mL each time). The crude product is basic hot-extracted three times with toluene over Alox, then 2x from 1, 4-dioxane to crystallized and finally sublimated in a high vacuum. Yield: 18.0 g (30.1 mmol, 49%); Purity > 99.9% according to HPLC.

The following connections can be represented analogously. Pd2(dba)3 or Pd(OAc)2 with X-Phos or S-Phos can also be used as a catalyst system. Column chromatography, hot extraction or recrystallization can be used for purification. Common solvents such as ethanol, butanol, acetone, ethyl acetate, acetonitrile, toluene, xylene, dichloromethane, methanol, tetrahydrofuran, n-butyl acetate, 1,4-dioxane or high boilers such as dimethyl sulfoxide, N ,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, etc. can be used.

P3a:

S6a (17.48 g, 60.0 mmol) is placed in DMSO (400 mL), treated with sodium te/t-butanolate (6.34 g, 66.0 mmol) and stirred at room temperature for 30 min. Then 2-chloro-4-d5-phenyl-quinazoline (16.25 g, 66.0 mmol) [CAS-1614244-83-5] is added and the reaction is stirred at room temperature for 24 h. The solvent is then removed in vacuo and the residue is stirred hot with 1500 mL ethanol. The crude product is basic hot-extracted three times with o-xylene over Alox, then recrystallized twice from DMF and finally sublimated in a high vacuum. Yield: 16.52 g (33.0 mmol, 55%); Purity > 99.9% according to HPLC. The following connections can be represented analogously. Column chromatography, hot extraction or recrystallization can be used for purification. Common solvents such as ethanol, butanol, acetone, ethyl acetate, acetonitrile, toluene, xylene, dichloromethane, methanol, tetrahydrofuran, n-butyl acetate, 1,4-dioxane or high boilers such as dimethyl sulfoxide, N,N- dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, etc. can be used.

P4a:

S6a (17.48 g, 60.0 mmol) and 2-chloro-3-phenylquinoxaline (20.0 g, 60.0 mmol) [CAS-7065-92-1] are placed in DMF (350 mL), with potassium phosphate (38.20 g, 180.0 mmol) added and stirred under reflux for 24 h. After cooling, the solvent is removed in vacuo and the residue is suspended in 250 mL ethanol and 250 mL water. The solid is filtered off and washed with ethanol (5×150 mL). The crude product is subjected to basic hot extraction twice with toluene and twice with n-butyl acetate over Alox and then sublimed under high vacuum.

Yield: 13.96 g (28.2 mmol, 47%); Purity > 99.9% according to HPLC.

The following connections can be represented analogously. Column chromatography, hot extraction or recrystallization can be used for purification. Common solvents such as ethanol, butanol, acetone, ethyl acetate, acetonitrile, toluene, xylene, dichloromethane, methanol, tetrahydrofuran, n-butyl acetate, 1,4-dioxane or high boilers such as dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, etc. can be used.

P5a:

S13a (33.3 mmol), 2-[1,1'-Biphenyl]-4-yl-4-(3-bromophenyl)-6-phenyl-1,3,5-triazine (35.0 mmol) [CAS-1955546-91 -4] and K3PO4 (14.14 g, 66.6 mmol) are placed in toluene/dioxane/water (200 mL/200 mL/100 mL) and rendered inert for 30 min. Triphenylphosphine (175 mg, 0.67 mmol) and Pd2(dba)3 (305 mg, 0.33 mmol) are then added one after the other and the mixture is stirred under reflux for 16 h. The batch is worked up by extraction with toluene and water. The combined organic phases are dried over Na2SÜ4 and the solvent is drawn off on a rotary evaporator. The crude product is hot-extracted three times with toluene/hepan 1:1, recrystallized twice from n-butyl acetate and finally sublimed under high vacuum. Yield 10.6 g (15.7 mmol, 47%) Purity > 99.9% according to HPLC.

The following connections can be represented analogously. S-Phos or X-Phos or P(o-tol)3 with Pd2(dba)3 or Pd(OAc)2 can also be used as a catalyst system. For purification, column chromato- graphy, hot extraction or recrystallization can be used. Common solvents such as ethanol, butanol, acetone, ethyl acetate, acetonitrile, toluene, xylene, dichloromethane, methanol, tetrahydrofuran, n-butyl acetate, 1,4-dioxane or high boilers such as dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, etc. can be used.

Manufacture of the OLEDs

Pretreatment for Examples C1 to E5h: Glass flakes coated with structured ITO (indium tin oxide) with a thickness of 50 nm are first treated with an oxygen plasma, followed by an argon plasma, before the coating. These plasma-treated glass flakes form the substrates on which the OLEDs are applied.

In principle, the OLEDs 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 precise structure of the OLEDs can be found in Table 1. The materials required to produce the OLEDs are shown in Table 3. The data of the OLEDs are listed in Table 2.

All materials are thermally evaporated 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 added to the matrix material or matrix materials by co-evaporation in a certain proportion by volume. A specification such as P1a:IC2:TER1 (57%:40%:3%) means that the material P1a accounts for 57% by volume, IC2 for 40% by volume and TER1 for 3% by volume in the layer present. Analogously, the electron transport layer can also consist of a mixture of two materials.

The OLEDs are characterized by default. For this purpose, the electroluminescence spectra, the external quantum efficiency (EQE, measured in %) as a function of the luminance, calculated from current-voltage-luminance characteristics assuming a Lambertian radiation characteristic, and the service life are determined. The electroluminescence spectra are determined at a luminance of 1000 cd/m ² and from this calculates the CIE 1931 x and y color coordinates. The specification U1000 in Table 3 designates the voltage required for a luminance of 1000 cd/m ² . EQE1000 designates the external quantum efficiency that can be achieved at 1000 cd/m ² . The service life LD is defined as the time after which the luminance drops from the initial luminance to a certain proportion L1 when operated with a constant current density jo. An indication of L1 = 95% in Table 3 means that the service life given in column LD corresponds to the time after which the luminance falls to 95% of its initial value.

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

The materials according to the invention are used in examples E1a-E1n, E2a-E2j, E3a-E3f, E4a-E4e and E5a-E5h as matrix material in the emission layer of red-phosphorescent OLEDs. Compared to the prior art (V1 to V5), a significant improvement in service life can be achieved with otherwise comparable parameters.

Table 1: Structure of the OLEDs

Table 2: Data of the OLEDs

Table 3: Structural formulas of the materials used in the OLEDs, unless previously described:

Claims

Claims Compound according to formula (1),

Formula (1) where the following applies to the symbols and indices used:

X is the same or different on each occurrence CR or N with the proviso that a maximum of two groups X per cycle represent N, and further provided that two adjacent groups X that are part of the same six-membered ring represent CR, where the adjacent radicals R form an aromatic or heteroaromatic ring system which is fused to the cycle and has 4 to 8 ring atoms, which can be substituted by one or more radicals R;

Y is on each occurrence, identically or differently, a BR, C(R)2, C=O, Si(R) ₂ , NR, NAr ¹ , O, S, Se, SO, SO ₂ , PR or P(=O) R, where if m or n is 0, the carbon atoms bonded to Y are each X; m and n are 0 or 1, where m + n is 1;

Ar ¹ is an aromatic ring system with 6 to 40 aromatic ring atoms, which can be substituted with one or more radicals R ¹ , or a heteroaromatic ring system with 5 to 40 aromatic ring atoms which can be substituted with one or more radicals R ¹ ;

R is the same or different on each occurrence H, D, F, CI, Br, I, N(Ar') ₂ , N(R ¹ ) ₂ , OAr', SAr', B(OR ¹ ) ₂ , CHO, C (=O) ^R1 , ^CR1 =C( ^R1 ) ₂ , CN, C(=O) ^OR1 , C(=O)NR1 , Si( ^R1 ₎₃ ^, NO2, P(=O)( R ¹ ) ₂ , OSO2R ¹ , OR ¹ , S(=O)R ¹ , S(=O)2R ¹ , SR ¹ , a straight-chain alkyl group with 1 to 20 carbon atoms or an alkenyl or alkynyl group with 2 to 20 C atoms or a branched or cyclic alkyl group having 3 to 20 C atoms, it being possible for the alkyl, alkenyl or alkynyl group to be substituted by one or more radicals R ¹ in each case, one or more non-adjacent CH2 groups being replaced by - R ¹ C=CR ¹ -, -C C-, Si(R ¹ ) ₂ , NR ¹ , CONR ¹ , C=O, C=S, -C(=O)O-, P(=O)(R ¹ ), -O-, -S-, SO or SO2 can be replaced, or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, preferably having 5 to 40 aromatic ring atoms, which can each be substituted by one or more R ¹ radicals , where two or more of the same cycl us bonded radicals R together can form an aliphatic, heteroaliphatic, aromatic or heteroaromatic ring system which can be substituted with one or more radicals R ¹ , and where two radicals R bonded to the same carbon or silicon atom are monocyclic or polycyclic, aliphatic, aromatic or can form a heteroaromatic ring system with one another, which can be substituted with one or more radicals R ¹ ;

R ¹ is the same or different on each occurrence H, D, F, I, B(OR ² )2, N(R ² ) ₂ , CHO, C(=O)R ² , CR ² =C(R ² ) ₂ , CN, C(=O)OR ² , Si(R ² ) ₃ , NO2, P(=O)(R ² ) ₂ , OSO2R ² , SR ² , OR ² , S(=O)R ² , S( =O) ₂ R ² , a straight-chain alkyl group having 1 to 20 carbon atoms or an alkenyl or - 166 -

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 each be substituted with one or more radicals R ² and where one or more CH2 groups in the above groups by -R ² C=CR ² - O-, -S-, SO or SO2 can be replaced and one or more H atoms in the above groups can be replaced by D, F, Cl, Br, I, CN or NO2, or an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, each of which may be substituted by one or more R ² radicals, where two or more R ¹ radicals together can form an aliphatic, heteroaliphatic, aromatic or heteroaromatic ring system;

R ² is the same or different on each occurrence and is H, D, F, CN or an aliphatic, aromatic or heteroaromatic organic radical having 1 to 20 carbon atoms, in which one or more H atoms can also be replaced by D or F; two or more substituents R ² can be linked to one another and form a ring. A compound according to claim 1 comprising a structure of formula (2),

Formula (2) where the symbols and indices used have the meanings given in claim 1 and the following also applies:

X is the same or different on each occurrence CR or N, with the proviso that a maximum of two X groups per cycle are N; and two adjacent groups X, which are part of the same cycle, stand for C, to which a group of formula (2) via the * - 167 - designated bonds form an aromatic or heteroaromatic ring system fused to the cycle;

Q is the same or different on each occurrence CR ¹ or N, with the proviso that a maximum of two Q groups per cycle are N. Compound according to one or more of claims 1 or 2, selected from the compounds of the formulas (3) or (4), wherein the symbols used have the meanings given in claim 2. Compound according to one or more of Claims 1 to 3, selected from the compounds of the formulas (5) to (8),

Formula (5) Formula (6) - 168 -

Formula (7) Formula (8) where the symbols used have the meanings given in claim 2. Compound according to one or more of Claims 1 to 4, selected from the compounds of the formulas (5-1) to (8-1),

Formula (5-1) Formula (6-1)

Formula (7-1) Formula (8-1) where the symbols used have the meanings given in claim 1. Compound according to one or more of Claims 1 to 5, characterized in that Y represents NAr ¹ , O or S. Formulation containing at least one compound according to one or more of Claims 1 to 6 and at least one further compound and/or at least one solvent. Use of a compound according to one or more of claims 1 to 6 and/or a formulation according to claim 7 in an electronic device. Electronic device containing at least one compound according to one or more of claims 1 to 6 and / or a formulation according to claim 7. Electronic device according to claim 9, wherein it is an organic electroluminescent device, characterized in that the compound according to one or more of Claims 1 to 6 in an emitting layer as a matrix material for phosphorescent or fluorescent emitters or for emitters which exhibit 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.