CONNECTIONS FOR ELECTRONIC DEVICES

Description

[0001] The present application relates to fluorene derivatives and spirobifluorene derivatives in which one of the benzene rings is replaced by a heteroaryl ring. The compounds are suitable for use in electronic devices.

[0002] For the purposes of this application, "electronic devices" refers to so-called organic electronic devices, which contain organic semiconductor materials as functional materials. In particular, this includes OLEDs (organic electroluminescent devices). The term OLED refers to electronic devices that contain one or more layers of organic compounds and emit light when an electrical voltage is applied. The structure and general operating principle of OLEDs are known to those skilled in the art.

[0003] There is great interest in improving the performance of electronic devices, especially OLEDs. A completely satisfactory solution has not yet been found in these areas.

[0004] Emission layers and layers with electron-transporting properties have a significant influence on the performance characteristics of electronic devices. New compounds are still being sought for use in these layers, particularly electron-transporting compounds and compounds that can serve as electron-transporting matrix materials, especially for phosphorescent emitters, within an emitting layer. In this application, these compounds should lead to electronic devices exhibiting high efficiency, long lifetime, and low operating voltage. Specifically, compounds with a high glass transition temperature, high stability, and high electronic conductivity are being sought. High compound stability is a prerequisite for achieving a long lifetime for the electronic device.

[0005] In the prior art, heterofluoro- and heterospirobifluorene derivatives with fused phenyl groups, as well as bipolar heterofluoro- and heterospirobifluorene derivatives, which are in particular substituted with N-carbazole, are known as electron transport materials and electron transporting matrix materials for electronic devices.

[0006] KR 2014 / 0109058 A describes, among other things, fluorine and spirobifluorene derivatives in which a benzene ring is replaced by a pyrrole ring and which have a diarylamine group as a substituent. These compounds with hole-transporting properties can be used in organic electronic devices.

[0007] However, there remains a need for alternative connections suitable for use in electronic devices, particularly connections that exhibit one or more of the aforementioned advantageous properties. Further improvements are needed in the performance data achieved when using these connections in electronic devices, especially regarding device lifespan, operating voltage, and efficiency.

[0008] It has now been found that certain fluorene derivatives, as well as spirobifluorene derivatives in which one of the benzene rings is replaced by a heteroaryl ring, are exceptionally well-suited for use in electronic devices. They are particularly suitable for use in OLEDs, specifically as electron transport materials and as electron-transporting matrix materials, especially for phosphorescent emitters. The compounds found result in long lifetimes, high efficiency, and low operating voltages for the electronic devices. Furthermore, the compounds preferably exhibit a high glass transition temperature, high stability, and high electron conductivity.

[0009] The subject of the present application is therefore combinations according to the following formula (I) where: Y is chosen from O, S, NAr° and CAr 1< in each occurrence, either the same or different, where at least one Y is chosen from O, S and NAr 0<; Z is chosen from N and CR 1< in each occurrence, either the same or different; Ar 0< is chosen from aromatic ring systems with 6 to 40 aromatic ring atoms substituted with R 2< residues and heteroaromatic ring systems with 5 to 40 aromatic ring atoms substituted with R 2< residues; Ar 1< is chosen in each occurrence, either the same or different, from H, D, F, Cl, Br, I, C(=O)R 2< , CN, Si(R 2< ) 3 , P(=O)(R 2< ) 2 , OR 2< , S(=O)R 2< , S(=O) 2 R 2< , straight-chain alkyl or alkoxy groups with 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups with 3 to 20 C atoms, alkenyl or alkynyl groups with 2 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms;wherein the aforementioned alkyl, alkoxy, alkenyl, and alkynyl groups and the aforementioned aromatic and heteroaromatic ring systems are each substituted with R2< residues; and wherein one or more CH2 groups in the aforementioned alkyl, alkoxy, alkenyl, and alkynyl groups may be replaced by -R2< C=CR2< -, -C≡C-, Si(R2< )2 , C=O, C=NR2< , -C(=O)O-, -C(=O)NR2< -, NR2< , P(=O)(R2< ), -O-, -S-, SO, or SO2; wherein it is excluded that two Ar1< groups are linked together to form a mono- or polycyclic, aliphatic, or aromatic ring system;R< is chosen the same or differently for each occurrence from H, D, F, Cl, Br, I, C(=O)R1, CN, Si(R1)3, N(R1)2, P(=O)(R1)2, OR1, S(=O)R1, S(=O)2R1, straight-chain alkyl, alkoxy, or thioalkyl groups with 1 to 20 carbon atoms, branched or cyclic alkyl, alkoxy, or thioalkyl groups with 3 to 20 carbon atoms, alkenyl or alkynyl groups with 2 to 20 carbon atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, heteroaromatic ring systems with 5 to 40 aromatic ring atoms, aryloxy or heteroaryloxy groups with 5 to 40 aromatic ring atoms, and aralkyl groups with 5 to 40 aromatic ring atoms; wherein the two residues R 0< can be linked together and can form an aliphatic or heteroaliphatic ring, so that a spiro compound is formed at position 8 of the fluorene derivative, in particular a spirobifluorene derivative;wherein the aforementioned alkyl, alkoxy, thioalkyl, alkenyl, alkynyl, aryloxy, heteroaryloxy and aralkyl groups and the aforementioned aromatic ring systems and heteroaromatic ring systems are each substituted with R1< residues; and wherein one or more CH2 groups in the aforementioned alkyl, alkoxy, thioalkyl, alkenyl, alkynyl, aryloxy, heteroaryloxy and aralkyl groups may be replaced by -R1<C=CR1<-, -C≡C-, Si(R1<)2, C=O, C=NR1<, -C(=O)O-, -C(=O)NR1<-, NR1<, P(=O)(R1<), -O-, -S-, SO or SO2;R1< is chosen in each instance as the same or different from H, D, F, Cl, Br, I, C(=O)R5<, CN, Si(R5<)3, P(=O)(R5<)2, OR5<, S(=O)R5<, S(=O)2R5<, straight-chain alkyl or alkoxy groups with 1 to 20 carbon atoms, branched or cyclic alkyl or alkoxy groups with 3 to 20 carbon atoms, alkenyl or alkynyl groups with 2 to 20 carbon atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms; wherein two or more R1< groups may be linked together and may form an aliphatic or heteroaliphatic ring; wherein the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups and the aforementioned aromatic ring systems and heteroaromatic ring systems are each substituted with R 5< residues;and wherein one or more CH 2 groups in the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups may be replaced by -R 5< C=CR 5< -, -C≡C-, Si(R 5< ) 2 , C=O, C=NR 5< , -C(=O)O-, -C(=O)NR 5< -, NR 5< , P(=O)(R 5< ), -O-, -S-, SO or SO 2; R 2< is chosen in each occurrence as either the same or different from H, D, F, Cl, Br, I, C(=O)R 5< , CN, Si(R 5< ) 3 , P(=O)(R 5< ) 2 , OR 5< , S(=O)R 5< , S(=O) 2 R 5< , straight-chain alkyl or alkoxy groups with 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups with 3 to 20 C atoms, alkenyl or alkynyl groups with 2 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms; wherein two or more R 2< residues can be linked together and form a ring;wherein the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups and the aforementioned aromatic and heteroaromatic ring systems are each substituted with R 5< residues; and wherein one or more CH 2 groups in the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups may be replaced by -R 5< C=CR 5< -, -C=C-, Si(R 5< ) 2 , C=O, C=NR 5< , -C(=O)O-, -C(=O)NR 5< -, NR 5< , P(=O)(R 5< ), -O-, -S-, SO or SO 2; R 5< is chosen the same or differently for each occurrence from H, D, F, Cl, Br, I, C(=O)R 6< , CN, Si(R 6< ) 3 , P(=O)(R 6< ) 2 , OR 6< , S(=O)R 6< , S(=O) 2 R 6< , straight-chain alkyl or alkoxy groups with 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups with 3 to 20 C atoms, alkenyl or alkynyl groups with 2 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms;wherein two or more R 5< residues can be linked together and form a ring; wherein the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups and the aforementioned aromatic ring systems and heteroaromatic ring systems are each substituted with R 6< residues; and wherein one or more CH 2 groups in the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups can be replaced by -R 6< C=CR 6< -, -C=C-, Si(R 6< ) 2 , C=O, C=NR 6< , -C(=O)O-, -C(=O)NR 6< -, NR 6< , P(=O)(R 6< ), -O-, -S-, SO or SO 2; R 6< is chosen in each occurrence as either the same or different from H, D, F, Cl, Br, I, CN, alkyl or alkoxy groups with 1 to 20 C atoms, alkenyl or alkynyl groups with 2 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms and heteroaromatic ring systems with 5 to 40 aromatic ring atoms; wherein two or more R 6< residues can be linked together and can form a ring;and wherein the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups, aromatic ring systems and heteroaromatic ring systems may be substituted with one or more residues selected from F and CN; and in formula (I) at least one residue R 1< , one group Ar 0< or one group Ar 1< is substituted by a group A corresponding to formula (A): ; where: * denotes the bond to the structure of formula (I); Ar L< is chosen, in each occurrence, either the same or different from aromatic ring systems with 6 to 40 aromatic ring atoms substituted with R 2< residues, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms substituted with R 2< residues; ET is, in each occurrence, either the same or different from an electron-transporting group chosen from electron-deficient heteroaromatic groups to which one or more Ar 2< groups are bonded;Ar 2< is chosen the same or differently for each occurrence from H, D, F, Cl, Br, I, C(=O)R 3< , CN, Si(R 3< ) 3 , P(=O)(R 3< ) 2 , OR 3< , S(=O)R 3< , S(=O) 2 R 3< , straight-chain alkyl or alkoxy groups with 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups with 3 to 20 C atoms, alkenyl or alkynyl groups with 2 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms; wherein the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups and the aforementioned aromatic and heteroaromatic ring systems are each substituted with R3< residues; wherein one or more CH2 groups in the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups may be replaced by -R3< C=CR3< -, -C=C-, Si(R3< )2 , C=O, C=NR3< , -C(=O)O-, -C(=O)NR3< -, NR3< , P(=O)(R3< ), -O-, -S-, SO or SO2;and wherein two or more adjacent groups Ar 2< can form a mono- or polycyclic, aliphatic or aromatic ring system together; R3< is chosen to be the same or different in each occurrence and is from H, D, F, Cl, Br, I, C(=O)R5<, CN, Si(R5<)3, N(R5<)2, P(=O)(R5<)2, OR5<, S(=O)R5<, S(=O)2R5<, straight-chain alkyl or alkoxy groups with 1 to 20 carbon atoms, branched or cyclic alkyl or alkoxy groups with 3 to 20 carbon atoms, alkenyl or alkynyl groups with 2 to 20 carbon atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms; wherein two or more R3< groups can be linked together and form a ring; wherein the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups and the aforementioned aromatic ring systems and heteroaromatic ring systems are each substituted with R 5< residues;and wherein one or more CH₂ groups in the aforementioned alkyl, alkoxy, alkenyl, and alkynyl groups may be replaced by -R₅< C=CR₅< -, -C=C-, Si(R₅< )₂ , C=O, C=NR₅< , -C(=O)O-, -C(=O)NR₅< -, NR₅< , P(=O)(R₅< ), -O-, -S-, SO, or SO₂; and n is equal to 0 or 1, wherein in the case n=0 the group ArL< is omitted and the group FG is directly bonded to the structure of formula (I) via a single bond.

[0010] Consequently, by definition, the compounds of formula (I) always contain at least one substituent of formula (A) with an electron-transporting group ET.

[0011] The counting method for the heterofluoro derivatives according to the present application is defined as follows:

[0012] The numbering method for the hetero-spirobifluorene derivatives according to the present application is defined as follows:

[0013] The following definitions apply to the chemical groups used in this application. They apply unless more specific definitions are given.

[0014] For the purposes of this invention, an aryl group is understood to be either a single aromatic cycle, i.e., benzene, or a condensed aromatic polycycle, for example, naphthalene, phenanthrene, or anthracene. A condensed aromatic polycycle, as defined in this application, consists of two or more single aromatic cycles condensed together. Condensation between cycles means that the cycles share at least one edge. An aryl group, as defined in this invention, contains 6 to 40 aromatic ring atoms. Furthermore, an aryl group contains no heteroatoms as aromatic ring atoms, but only carbon atoms.

[0015] A heteroaryl group within the meaning of this invention is understood to be either a single heteroaromatic cycle, for example pyridine, pyrimidine, or thiophene, or a condensed heteroaromatic polycycle, for example quinoline or carbazole. A condensed heteroaromatic polycycle within the meaning of the present application consists of two or more condensed single aromatic or heteroaromatic cycles, wherein at least one of the aromatic and heteroaromatic cycles is a heteroaromatic cycle. Condensation between cycles means that the cycles share at least one edge. A heteroaryl group within the meaning of this invention contains 5 to 40 aromatic ring atoms, at least one of which is a heteroatom. The heteroatoms of the heteroaryl group are preferably selected from N, O, and S.

[0016] The term aryl or heteroaryl group, which may be substituted with the aforementioned residues, refers in particular to groups derived from benzene, naphthalene, anthracene, phenanthrene, pyrene, dihydropyrene, chrysene, perylene, triphenylene, fluoranthene, benzanthracene, benzphenanthrene, tetracene, pentacene, benzopyrene, furan, benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene, isobenzothiophene, dibenzothiophene, 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, benzimidazolo[1,2-a]benzimidazole. Naphthimidazole, phenanthrimidazole, pyridimidazole, pyrazinimidazole, quinoxalinimidazole, oxazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, 1,2-thiazole, 1,3-thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine, benzopyrimidine, quinoxaline, pyrazine, phenazine,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.

[0017] An aryloxy group, as defined in the present invention, is understood to be an aryl group, as defined above, which is bonded via an oxygen atom. An analogous definition applies to heteroaryloxy groups.

[0018] An aromatic ring system within the meaning of this invention is a system that does not necessarily contain only aryl groups, but may additionally contain one or more non-aromatic rings fused to at least one aryl group. These non-aromatic rings contain exclusively carbon atoms as ring atoms. Examples of groups encompassed by this definition are tetrahydronaphthalene, fluorene, and spirobifluorene. Furthermore, the term aromatic ring system includes systems consisting of two or more aromatic ring systems linked to one another by single bonds, for example, biphenyl, terphenyl, 7-phenyl-2-fluorenyl, quaterphenyl, and 3,5-diphenyl-1-phenyl. An aromatic ring system within the meaning of this invention contains 6 to 40 carbon atoms and no heteroatoms in the ring system. The definition of "aromatic ring system" does not include heteroaryl groups.

[0019] A heteroaromatic ring system corresponds to the above definition of an aromatic ring system, with the difference that it must contain at least one heteroatom as a ring atom. As with aromatic ring systems, the heteroaromatic ring system need not consist exclusively of aryl and heteroaryl groups; it may additionally contain one or more non-aromatic rings fused to at least one aryl or heteroaryl group. The non-aromatic rings may consist exclusively of carbon atoms as ring atoms, or they may additionally contain one or more heteroatoms, preferably chosen from nitrogen, oxygen, and sulfur. Benzopyranyl is an example of such a heteroaromatic ring system.Furthermore, the term "heteroaromatic ring system" is understood to mean systems consisting of two or more aromatic or heteroaromatic ring systems linked to one another by single bonds, such as 4,6-diphenyl-2-triazinyl. A heteroaromatic ring system within the meaning of this invention contains 5 to 40 ring atoms selected from carbon and heteroatoms, wherein at least one of the ring atoms is a heteroatom. The heteroatoms of the heteroaromatic ring system are preferably selected from N, O, and S.

[0020] The terms "heteroaromatic ring system" and "aromatic ring system" as defined in the present application differ in that an aromatic ring system cannot contain a heteroatom as a ring atom, whereas a heteroaromatic ring system must contain at least one heteroatom as a ring atom. This heteroatom can be a ring atom of a non-aromatic heterocyclic ring or a ring atom of an aromatic heterocyclic ring.

[0021] According to the definitions above, every aryl group is encompassed by the term "aromatic ring system", and every heteroaryl group is encompassed by the term "heteroaromatic ring system".

[0022] An aromatic ring system with 6 to 40 aromatic ring atoms or a heteroaromatic ring system with 5 to 40 aromatic ring atoms includes, in particular, groups derived from the groups mentioned above under aryl groups and heteroaryl groups, as well as from biphenyl, terphenyl, quaterphenyl, fluorene, spirobifluorene, dihydrophenanthrene, dihydropyrene, tetrahydropyrene, indenofluorene, truxene, isotruxene, spirotruxene, spiroisotruxene, indenocarbazole, or combinations of these groups.

[0023] Within the scope of the present invention, the following are preferably defined as a straight-chain alkyl group with 1 to 20 carbon atoms, a branched or cyclic alkyl group with 3 to 20 carbon atoms, or an alkenyl or alkynyl group with 2 to 40 carbon atoms, in which individual hydrogen atoms or CH₂ groups may also be substituted by the groups mentioned above in the definition of the residues: methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, 2-methylbutyl, n-pentyl, s-pentyl, cyclopentyl, neopentyl, n-hexyl, cyclohexyl, neo-hexyl, 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, pentinyl, hexynyl or octynyl are understood.

[0024] Unter einer Alkoxy- oder Thioalkylgruppe mit 1 bis 20 C-Atomen, in der auch einzelne H-Atome oder CH 2 -Gruppen durch die oben bei der Definition der Reste genannten Gruppen substituiert sein können, werden bevorzugt Methoxy, Trifluormethoxy, 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, Pentafluorethoxy, 2,2,2-Trifluorethoxy, 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, Trifluormethylthio, Pentafluorethylthio, 2,2,2-Trifluorethylthio, Ethenylthio, Propenylthio, Butenylthio, Pentenylthio, Cyclopentenylthio, Hexenylthio, Cyclohexenylthio, Heptenylthio, Cycloheptenylthio, Octenylthio, Cyclooctenylthio, Ethinylthio, Propinylthio, Butinylthio,Pentinylthio, hexinylthio, heptinylthio, or octinylthio are understood.

[0025] In the context of this application, the phrase "two or more residues can form a ring" is understood to mean, among other things, that the two residues are linked to each other by a chemical bond. Furthermore, the above phrase is also intended to mean that if one of the two residues represents hydrogen, the second residue binds to the position to which the hydrogen atom was bonded, forming a ring.

[0026] According to a preferred embodiment of the invention, in formula (I) exactly two Ys are selected, more preferably exactly one Y is selected from NAr 0< , O and S, and the other two Ys are equal to CAr 1< . Particularly preferably exactly one Y is selected from O and S, most preferably from S, and the other two Ys are equal to CAr 1< .

[0027] In a preferred embodiment of the invention, the compound of formula (I) is therefore selected from the compounds of the following formulas (II), (III) and (IV): where at least one group A is present for each formula.

[0028] Preferred among the above-mentioned formulas are formulas (II) and (IV), in particular formula (II), where Y is preferably equal to O or S, and especially preferably Y is equal to S.

[0029] Preferably, at most two groups Z in formula (I) are equal to N; particularly preferred, at most one group Z in formula (I) is equal to N; most particularly preferred, no group Z is equal to N. The remaining groups Z are accordingly equal to CR 1< . Furthermore, it is preferred that neighboring groups Z in a ring are not equal to N.

[0030] Ar 0< is preferably chosen, in each occurrence, as the same or different from aromatic ring systems with 6 to 40 aromatic ring atoms, each of which is substituted with R 2< residues. Particularly preferred is Ar 0< selected from phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, fluorenyl, in particular 9,9'-dimethylfluorenyl and 9,9'-diphenylfluorenyl, benzofluorenyl, spirobifluorenyl, indenofluorenyl, indenocarbazolyl, dibenzofuranyl, dibenzothiophenyl, benzofuranyl, benzothiophenyl, benzothiophenyl, benzo-condensed dibenzofuranyl, benzo-condensed dibenzothiophenyl, naphthyl-substituted phenyl, fluorenyl-substituted phenyl, spirobifluorenyl-substituted phenyl, dibenzofuranyl-substituted phenyl, dibenzothiophenyl-substituted phenyl, carbazolyl-substituted phenyl, pyridyl-substituted phenyl, pyrimidyl-substituted phenyl, and Triazinyl-substituted phenyl, wherein the aforementioned groups are each substituted with R 2< residues.Particularly preferred are phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, fluorenyl, especially 9,9'-dimethylfluorenyl and 9,9'-diphenylfluorenyl, naphthyl-substituted phenyl, fluorenyl-substituted phenyl, spirobifluorenyl-substituted phenyl, dibenzofuranyl-substituted phenyl, dibenzothiophenyl-substituted phenyl, carbazolyl-substituted phenyl, pyridyl-substituted phenyl, pyrimidyl-substituted phenyl, and triazinyl-substituted phenyl, wherein the aforementioned groups are each substituted with R2< groups. Most preferred is Ar0<, which is equivalent to phenyl substituted with R2< groups, wherein R2< is preferably equivalent to H.

[0031] Ar 1< is preferably selected, in each occurrence, as the same or different from H, D, straight-chain alkyl or alkoxy groups with 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups with 3 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms, wherein the alkyl groups, alkoxy groups, aromatic ring systems and heteroaromatic ring systems are each substituted with R 2< groups, excluding the possibility of two Ar 1< groups being linked together to form an aliphatic or heteroaliphatic ring; Ar 1< is particularly preferably selected, in each occurrence, as the same or different from H and aromatic ring systems with 6 to 40 aromatic ring atoms substituted with R 2< groups.Particularly preferred is Ar 1<, in each occurrence, being selected as the same or different from phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, fluorenyl, in particular 9,9'-dimethylfluorenyl and 9,9'-diphenylfluorenyl, benzofluorenyl, spirobifluorenyl, indenofluorenyl, indenocarbazolyl, dibenzofuranyl, dibenzothiophenyl, benzofuranyl, benzothiophenyl, benzocondensed dibenzofuranyl, benzocondensed dibenzothiophenyl, naphthyl-substituted phenyl, fluorenyl-substituted phenyl, spirobifluorenyl-substituted phenyl, dibenzofuranyl-substituted phenyl, dibenzothiophenyl-substituted phenyl, carbazolyl-substituted phenyl, pyridyl-substituted phenyl, pyrimidyl-substituted phenyl, Triazinyl-substituted phenyl, wherein the aforementioned groups are each substituted with R 2< residues, and H.Even more preferred are phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, fluorenyl, in particular 9,9'-dimethylfluorenyl and 9,9'-diphenylfluorenyl, naphthyl-substituted phenyl, fluorenyl-substituted phenyl, spirobifluorenyl-substituted phenyl, dibenzofuranyl-substituted phenyl, dibenzothiophenyl-substituted phenyl, carbazolyl-substituted phenyl, pyridyl-substituted phenyl, pyrimidyl-substituted phenyl, triazinyl-substituted phenyl, wherein the aforementioned groups are each substituted with R 2< groups, wherein R 2< is preferably equal to H, and H.

[0032] Preferred groups Ar 1< are shown in the following table: Ar 1< -1 Ar 1< -2 Ar 1< -3 Ar 1< -4 Ar 1< -5 Ar 1< -6 Ar 1< -7 Ar 1< -8 Ar 1< -9 Ar 1< -10 Ar 1< -11 Ar 1< -12 Ar 1< -13 Ar 1< -14 Ar 1< -15 Ar 1< -16 Ar 1< -17 Ar 1< -18 Ar 1< -19 Ar 1< -20 Ar 1< -21 Ar 1< -22 Ar 1< -23 Ar 1< -24 Ar 1< -25 Ar 1< -26 Ar 1< -27 Ar 1< -28 Ar 1< -29 Ar 1< -30 Ar 1< -31 Ar 1< -32 Ar 1< -33 Ar 1< -34 Ar 1< -35 Ar 1< -36 Ar 1< -37 Ar 1< -38 Ar 1< -39 Ar 1< -40 Ar 1< -41 Ar 1< -42 Ar 1< -43 Ar 1< -44 Ar 1< -45 Ar 1< -46 Ar 1< -47 Ar 1< -48 Ar 1< -49 Ar 1< -50 Ar 1< -51 Ar 1< -52 Ar 1< -53 Ar 1< -54 Ar 1< -55 Ar 1< -56 Ar 1< -57 Ar 1< -82 Ar 1< -83 Ar 1< -84 Ar 1< -85 Ar 1< -86 Ar 1< -87 Ar 1< -88 Ar 1< -89 Ar 1< -90 Ar 1< -91 Ar 1< -92 Ar 1< -93 Ar 1< -94 Ar 1< -95 Ar 1< -96 Ar 1< -97 Ar 1< -98 Ar 1< -99 Ar 1< -100 Ar 1< -101 Ar 1< -102 Ar 1< -103 Ar 1< -104 Ar 1< -105 Ar 1< -106 Ar 1< -107 Ar 1< -108 Ar 1< -109 Ar 1< -110 Ar 1< -111 Ar 1< -112 Ar 1< -113 Ar 1< -114 Ar 1< -115 Ar 1< -116 Ar 1< -117 Ar 1< -118 Ar 1< -119 Ar 1< -120 Ar 1< -121 Ar 1< -122 Ar 1< -123 Ar 1< -124 Ar 1< -125 Ar 1< -126 Ar 1< -127 Ar 1< -128 Ar 1< -129 Ar 1< -130 Ar 1< -131 Ar 1< -132 Ar 1< -133 Ar 1< -134 Ar 1< -135 Ar 1< -136 Ar 1< -137 Ar 1< -138 Ar 1< -139 Ar 1< -140 Ar 1< -141 -F -Cl Ar 1< -142 Ar 1< -143 Ar 1< -144 -Br -I -H Ar 1< -145 Ar 1< -146 Ar 1< -147 -CH 3 -CH 2 CH 3 Ar 1< -148 Ar 1< -149 Ar 1< -150 - CF 3 -CF 2 CF 3 Ar 1< -151 Ar 1< -152 Ar 1< -153 -OCF 3 -SCF 3 - SF 5 Ar 1< -154 Ar 1< -155 Ar 1< -156 -OCF 2 CF 3 -SCF 2 CF 3 Ar 1< -157 Ar 1< -158 Ar 1< -159 Ar 1< -160 Ar 1< -161 Ar 1< -162 -CN -SCN -OCH 2 CH 3 Ar 1< -163 Ar 1< -164 Ar 1< -165 - OCH 3 -SCH 3 -Si(CH 3 ) 3 Ar 1< -166 Ar 1< -167 Ar 1< -168 -Si(CH 3 ) 2 t-Bu -Si(iPr) 3 -Si(CH 3 ) 2 Ph Ar 1< -169 Ar 1< -170 Ar 1< -171 Si-(Ph) 3 C-(Ph) 3 -D Ar 1< -172 Ar 1< -173 Ar 1< -174 - CD 3 -CD 2 -CD 3 -C(CD 3 ) 3 Ar 1< -175 Ar 1< -176 Ar 1< -177 -CD 2 -(CD 3 ) 2 - OCD 3 -SCD 3 Ar 1< -178 Ar 1< -179 Ar 1< -180 -Si(CD 3 ) 3 Ar 1< -181 Ar 1< -182 Ar 1< -183 -CD 2 (CH 3 ) 2 Ar 1< -184 Ar 1< -185 Ar 1< -186 -CD 2 (CH 3 ) 3 Ar 1< -187 Ar 1< -188 Ar 1< -189 Ar 1< -190 Ar'-191, where the dashed lines represent the connections to the rest of formula (I). The groups (Ar) are 1 -1), (Ar 1 -2), (Ar 1 -8), (Ar 1 -28), (Ar 1 -30), (Ar 1 -31), (Ar 1 -34), (Ar 1 -34), (Ar 1 -43), (Ar 1 -44), (Ar 1 -144), (Ar 1 -163), (Ar 1 -189) and (Ar 1 -190) is particularly preferred.

[0033] R 1< is preferably selected in each occurrence as the same or different from H, D, F, CN, Si(R 5< ) 3 , straight-chain alkyl or alkoxy groups with 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups with 3 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms; wherein the aforementioned alkyl and alkoxy groups, the aforementioned aromatic ring systems and the aforementioned heteroaromatic ring systems are each substituted with R 5< residues; and wherein in the aforementioned alkyl or alkoxy groups one or more CH 2 groups may be replaced by -C≡C-, -R 5< C=CR 5< -, Si(R 5< ) 2 , C=O, C=NR 5< , -NR 5< -, -O-, - S-, -C(=O)O- or -C(=O)NR 5< -.Particularly preferably, R1 is selected, in each occurrence, as the same or different from H, D, Si(R5)3, straight-chain alkyl groups with 1 to 20 carbon atoms, which may be deuterated, branched or cyclic alkyl groups with 3 to 20 carbon atoms, which may be deuterated, aromatic ring systems with 6 to 40 aromatic ring atoms, which may be deuterated, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms, which may be deuterated, wherein the aforementioned alkyl groups, the aforementioned aromatic ring systems, and the aforementioned heteroaromatic ring systems are each substituted with R5 substituents, which are preferably equal to H. R1 is most preferably equal to H.

[0034] Preferably, it is excluded that R 1< as well as Ar 0< and Ar 1< represent a carbazolyl group which is bonded to the rest of formula (I) via its N atom.

[0035] Preferred groups R 1< are shown in the following table: R 1< -1 R 1< -2 R 1< -3 R 1< -4 R 1< -5 R 1< -6 R 1< -7 R 1< -8 R 1< -9 R 1< -10 R 1< -11 R 1< -12 R 1< -13 R 1< -14 R 1< -15 R 1< -16 R 1< -17 R 1< -18 R 1< -19 R 1< -20 R 1< -21 R 1< -22 R 1< -23 R 1< -24 R 1< -25 R 1< -26 R 1< -27 R 1< -28 R 1< -29 R 1< -30 R 1< -31 R 1< -32 R 1< -33 R 1< -34 R 1< -35 R 1< -36 R 1< -37 R 1< -38 R 1< -39 R 1< -40 R 1< -41 R 1< -42 R 1< -43 R 1< -44 R 1< -45 R 1< -46 R 1< -47 R 1< -48 R 1< -49 R 1< -50 R 1< -51 R 1< -52 R 1< -53 R 1< -54 R 1< -55 R 1< -56 R 1< -57 R 1< -82 R 1< -83 R 1< -84 R 1< -85 R 1< -86 R 1< -87 R 1< -88 R 1< -89 R 1< -90 R 1< -91 R 1< -92 R 1< -93 R 1< -94 R 1< -95 R 1< -96 R 1< -97 R 1< -98 R 1< -99 R 1< -100 R 1< -101 R 1< -102 R 1< -103 R 1< -104 R 1< -105 R 1< -106 R 1< -107 R 1< -108 R 1< -109 R 1< -110 R 1< -111 R 1< -112 R 1< -113 R 1< -114 R 1< -115 R 1< -116 R 1< -117 R 1< -118 R 1< -119 R 1< -120 R 1< -121 R 1< -122 R 1< -123 R 1< -124 R 1< -125 R 1< -126 R 1< -127 R 1< -128 R 1< -129 R 1< -130 R 1< -131 R 1< -132 R 1< -133 R 1< -134 R 1< -135 R 1< -136 R 1< -137 R 1< -138 R 1< -139 R 1< -140 R 1< -141 -F -Cl R 1< -142 R 1< -143 R 1< -144 -Br -I -H R 1< -145 R 1< -146 R 1< -147 -CH 3 -CH 2 CH 3 R 1< -148 R 1< -149 R 1< -150 - CF 3 -CF 2 CF 3 R 1< -151 R 1< -152 R 1< -153 -OCF 3 -SCF 3 - SF 5 R 1< -154 R 1< -155 R 1< -156 -OCF 2 CF 3 -SCF 2 CF 3 R 1< -157 R 1< -158 R 1< -159 R 1< -160 R 1< -161 R 1< -162 -CN -SCN -OCH 2 CH 3 R 1< -163 R 1< -164 R 1< -165 - OCH 3 -SCH 3 -Si(CH 3 ) 3 R 1< -166 R 1< -167 R 1< -168 -Si(CH 3 ) 2 t-Bu -Si(iPr) 3 -Si(CH 3 ) 2 Ph R 1< -169 R 1< -170 R 1< -171 Si-(Ph) 3 C-(Ph) 3 -D R 1< -172 R 1< -173 R 1< -174 - CD 3 -CD 2 -CD 3 -C(CD 3 ) 3 R 1< -175 R 1< -176 R 1< -177 -CD 2 -(CD 3 ) 2 - OCD 3 -SCD 3 R 1< -178 R 1< -179 R 1< -180 -Si(CD 3 ) 3 R 1< -181 R 1< -182 R 1< -183 -CD 2 (CH 3 ) 2 R 1< -184 R 1< -185 R 1< -186 -CD 2 (CH 3 ) 3 R 1< -187 R 1< -188 R 1< -189 R 1< -190 R 1< -191, where the dashed lines represent the connections to the rest of formula (I). The groups (Ar) are 1 -1), (Ar 1 -2), (Ar 1 -8), (Ar 1 -28), (Ar 1 -30), (Ar 1 -31), (Ar 1 -34), (Ar 1 -34), (Ar 1 -43), (Ar 1 -44), (Ar 1 -144), (Ar 1 -163), (Ar 1 -189) and (Ar 1 -190) is particularly preferred.

[0036] R 2< is preferably selected in each occurrence as the same or different from H, D, F, CN, Si(R 5< ) 3 , straight-chain alkyl or alkoxy groups with 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups with 3 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms; wherein the aforementioned alkyl and alkoxy groups, the aforementioned aromatic ring systems and the aforementioned heteroaromatic ring systems are each substituted with R 5< residues; and wherein in the aforementioned alkyl or alkoxy groups one or more CH 2 groups may be replaced by -C≡C-, -R 5< C=CR 5< -, Si(R 5< ) 2 , C=O, C=NR 5< , -NR 5< -, -O-, - S-, -C(=O)O- or -C(=O)NR 5< -.Particularly preferably, R 2< is selected, in each occurrence, as the same or different from H, D, Si(R 5< ) 3 , straight-chain alkyl groups with 1 to 20 carbon atoms, which may be deuterated, branched or cyclic alkyl groups with 3 to 20 carbon atoms, which may be deuterated, aromatic ring systems with 6 to 40 aromatic ring atoms, which may be deuterated, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms, which may be deuterated, wherein the aforementioned alkyl groups, the aforementioned aromatic ring systems, and the aforementioned heteroaromatic ring systems are each substituted with R 5< substituents, which are preferably equal to H. Most preferably, R 2< is equal to H.

[0037] Preferably, only one or two groups A are present in formula (I), more preferably exactly one group A is present in formula (I).

[0038] If two groups A are present in formula (I), they are preferably both bonded to the heteroaromatic five-membered ring of formula (I).

[0039] The bridging group ArL< is preferably selected, in each instance, as either the same or different aromatic ring systems with 6 to 20 aromatic ring atoms substituted with R2< groups, or as heteroaromatic ring systems with 5 to 20 aromatic ring atoms substituted with R2< groups. Particularly preferred groups ArL< are selected, in each instance, as either the same or different divalent groups derived from benzene, biphenyl, terphenyl, naphthalene, fluorene, indenofluorene, indenocarbazole, spirobifluorene, dibenzofuran, and dibenzothiophene, each substituted with R2< groups. Most preferably, ArL< is a divalent group derived from benzene, biphenyl, dibenzofuran, or dibenzothiophene, each substituted with one or more R2< groups, wherein the R2< groups are preferably H in this case.

[0040] Preferably, n is equal to 0.

[0041] Preferred groups -(Ar L< ) n - for the case n=1 correspond to the following formulas: At L< -1 At L< -2 At L< -3 At L< -4 At L< -5 At L< -6 At L< -7 At L< -8 On L< -9 At L< -10 At L< -11 At L< -12 At L< -13 At L< -14 At L< -15 On L-< -16 On L< -17 On L< -18 On L< -19 At L< -20 At L< -21 At L< -22 At L< -23 At L< -24 At L< -25 At L< -26 On L< -27 At L< -28 On L< -29 At L< -30 On L< -31 At L< -32 At L< -33 At L< -34 At L< -35 At L< -36 On L< -37 At L< -38 On L< -39 At L< -40 At L< -41 At L< -42 At L< -43 At L< -44 At L< -45 At L< -46 At L< -47 At L< -48 At L< -49 At L< -50 At L< -51 At L< -52 The L< -53 The L< -54 The L< -55 The L< -56 The L< -57 The L< -58 The L< -59 The L< -60 The L< -61 The L< -62 The L< -63 The L< -64 The L< -65 The L< -72 The L< -73 The L< -74 The L< -75 The L< -76 The L< -77 The L< -78 The L< -79 The L< -80 The L< -81 The L< -82 where the dashed lines represent the ties to the rest of formula (I), and where the groups at the unsubstituted positions are each linked with residues R 2 are substituted, with the residues R 2 H is preferred in these positions.

[0042] Among the formulas mentioned above, the formulas (Ar L< -1), (Ar L< -2), (Ar L< -7), (Ar L< -12), (Ar L< -20), (Ar L< -31) are particularly preferred.

[0043] The electron-transporting group ET is preferably selected from heteroaryl groups with 5 to 40 aromatic ring atoms, of which at least one, preferably at least two and most preferably at least three are heteroatoms, which are preferably selected from N, O and / or S, and which are most preferably equal to N, wherein the heteroaryl groups are each substituted with groups Ar 2<

[0044] It is preferred that each group ET is substituted by at least one group Ar 2< , which is not equal to H, more preferably at least two groups Ar 2< , which are not equal to H.

[0045] The group ET is preferred if it is the same or different for each occurrence and is chosen from the groups of formulas (ET-1) to (ET-11) and (ET-11a) to (ET-11c): where Q' is chosen to be the same or different from CAr 2< or N at each occurrence; Q" is chosen to be the same or different from NR 2< , O or S at each occurrence; the dashed line marks the connection position to the rest of formula (I) and R 2< and Ar 2< are defined as above; and where at least one Q` is equal to N.

[0046] Particularly preferred groups ET are, in each occurrence, selected as identical or different from groups derived from pyridine, pyrazine, pyrimidine, pyridazine, 1,2,4-triazine, 1,3,5-triazine, quinoline, isoquinoline, quinoxaline, quinazoline, pyrazole, imidazole, benzimidazole, thiazole, benzothiazole, oxazole, oxadiazole, and benzooxazole, each substituted with groups Ar 2<. A most preferred group ET is pyridine, pyrazine, pyrimidine, pyridazine, 1,3,5-triazine, benzimidazole, and quinazoline substituted with one or more groups Ar 2<.

[0047] Particularly favored heteroaromatic electron-transporting groups ET are selected from formulas (ET-12) to (ET-35). where the dashed lines represent the ties to the rest of formula (I), and where groups of formulas (ET-12), (ET-13), (ET-14), (ET-20), (ET-21) and (ET-22) are particularly preferred, and groups of formula (ET-12) are most preferred.

[0048] Preferably, Ar 2< is selected in each occurrence as the same or different from H, straight-chain alkyl or alkoxy groups with 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups with 3 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms, wherein the alkyl groups, alkoxy groups, aromatic ring systems and heteroaromatic ring systems are each substituted with R 3< groups, and wherein two or more adjacent Ar 2< groups can form a mono- or polycyclic, aliphatic or aromatic ring system together.

[0049] Ar 2< is particularly preferably chosen, in each occurrence, as being the same or different from H and aromatic ring systems with 6 to 40 aromatic ring atoms substituted with R 3< residues.Furthermore, Ar 2< is particularly preferably selected in each occurrence as the same or different from phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, fluorenyl, in particular 9,9'-dimethylfluorenyl and 9,9'-diphenylfluorenyl, benzofluorenyl, spirobifluorenyl, indenofluorenyl, indenocarbazolyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, benzofuranyl, benzothiophenyl, benzo-condensed dibenzofuranyl, benzo-condensed dibenzothiophenyl, naphthyl-substituted phenyl, fluorenyl-substituted phenyl, spirobifluorenyl-substituted phenyl, dibenzofuranyl-substituted phenyl, dibenzothiophenyl-substituted phenyl, carbazolyl-substituted phenyl, pyridyl-substituted phenyl, pyrimidyl-substituted phenyl, Triazinyl-substituted phenyl, wherein the aforementioned groups are each substituted with residues R 3<, and H.Particularly preferred groups Ar 2< are chosen, in each occurrence, to be the same or different from phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, fluorenyl, in particular 9,9'-dimethylfluorenyl and 9,9'-diphenylfluorenyl, benzofluorenyl, spirobifluorenyl, indenofluorenyl, indenocarbazolyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, benzofuranyl, benzothiophenyl, benzo-condensed dibenzofuranyl, benzo-condensed dibenzothiophenyl, naphthyl-substituted phenyl, fluorenyl-substituted phenyl, spirobifluorenyl-substituted phenyl, dibenzofuranyl-substituted phenyl, dibenzothiophenyl-substituted phenyl, carbazolyl-substituted phenyl, pyridyl-substituted phenyl, pyrimidyl-substituted phenyl. Triazinyl-substituted phenyl, wherein the aforementioned groups are each substituted with residues R 3<, and H.

[0050] Particularly favored groups Ar 2< are chosen from H and the following formulas, either identical or different: Ar-1 Ar-2 Ar-3 Ar-4 Ar-5 Ar-6 Ar-7 Ar-8 Ar-9 Ar-10 Ar-11 Ar-12 Ar-13 Ar-14 Ar-15 Ar-18 Ar-19 Ar-20 Ar-21 Ar-22 Ar-23 Ar-24 Ar-25 Ar-26 Ar-27 Ar-28 Ar-29 Ar-30 Ar-31 Ar-32 Ar-33 Ar-34 Ar-35 Ar-36 Ar-37 Ar-38 Ar-39 Ar-40 Ar-41 Ar-42 Ar-43 Ar-44 Ar-45 Ar-46 Ar-47 Ar-48 Ar-49 Ar-50 Ar-51 Ar-52 Ar-53 Ar-54 Ar-55 Ar-56 Ar-57 Ar-58 Ar-59 Ar-60 Ar-61 Ar-62 Ar-63 Ar-64 Ar-65 Ar-66 Ar-67 Ar-68 Ar-69 Ar-70 Ar-71 Ar-72 Ar-73 Ar-74 Ar-75 Ar-76 Ar-77 Ar-78 Ar-79 Ar-80 Ar-81 Ar-82 Ar-83 Ar-84 Ar-85 Ar-86 Ar-87 Ar-88 Ar-89 Ar-90 Ar-91 Ar-92 Ar-93 Ar-94 Ar-95 Ar-96 Ar-97 Ar-98 Ar-99 Ar-100 Ar-101 Ar-102 Ar-103 Ar-104 Ar-105 Ar-106 Ar-107 Ar-108 Ar-109 Ar-110 Ar-111 Ar-112 Ar-113 Ar-114 Ar-115 Ar-116 Ar-117 Ar-118 Ar-119 Ar-120 Ar-121 Ar-122 Ar-123 Ar-124 Ar-125 Ar-126 Ar-127 Ar-128 Ar-129 Ar-130 Ar-131 Ar-132 Ar-133 Ar-134 Ar-135 Ar-136 Ar-137 Ar-138 Ar-139 Ar-140 Ar-141 Ar-142 Ar-143 Ar-144 Ar-145 Ar-146 Ar-147 Ar-148 Ar-149 Ar-150 Ar-151 Ar-152 Ar-153 Ar-154 Ar-155 Ar-156 Ar-157 Ar-158 Ar-159 Ar-160 Ar-161 Ar-162 Ar-163 Ar-164 Ar-165 Ar-166 Ar-167 Ar-168 Ar-169 Ar-170 Ar-171 Ar-172 Ar-173 Ar-174 Ar-175 Ar-176 Ar-177 Ar-178 Ar-179 Ar-180 Ar-181 Ar-182 Ar-183 Ar-184 Ar-185 Ar-186 Ar-187 Ar-188 Ar-189 Ar-190 Ar-191 Ar-192 Ar-193 Ar-194 Ar-195 Ar-196 Ar-197 Ar-198 Ar-199 Ar-200 Ar-201 Ar-202 Ar-203 Ar-204 Ar-205 Ar-206 Ar-207 Ar-208 Ar-209 Ar-210 Ar-211 Ar-212 Ar-213 Ar-214 Ar-215 Ar-216 Ar-217 Ar-218 Ar-219 Ar-220 Ar-221 Ar-222 Ar-223 Ar-224 Ar-225 Ar-226 Ar-227 Ar-228 Ar-229 Ar-230 Ar-231 Ar-232 Ar-233 Ar-234 Ar-235 Ar-236 Ar-237 Ar-238 Ar-239 Ar-240 Ar-241 Ar-242 Ar-243 Ar-244 Ar-245 Ar-246 Ar-247 Ar-248 Ar-250 Ar-251 Ar-252 Ar-253 Ar-254 Ar-255 Ar-256 Ar-257 Ar-258 Ar-259 Ar-260 Ar-261 Ar-262 Ar-263 Ar-264 Ar-265 Ar-266 Ar-267 Ar-268 Ar-269 Ar-270 Ar-271 Ar-272 Ar-273 Ar-274 where the groups at the unsubstituted positions are represented by remainders R 3 are substituted, where R 3 H is preferred in these positions, and the dashed bond represents the bond to the rest of group A.

[0051] Of the groups mentioned above, those of formulas (Ar-1), (Ar-3), (ar-16), (Ar-49), (Ar-63), (Ar-65), (Ar-66), (Ar-69), (Ar-78), (Ar-139) and (Ar-274) are most preferred, and especially formula (Ar-1).

[0052] According to a preferred embodiment, the groups Ar 2< in formula (A) are chosen to be identical. According to another preferred embodiment, the groups Ar 2< are chosen to be different.

[0053] Examples of particularly favored groups ET are the following groups, where the dashed lines represent the links to the rest of formula (I): groups ET-23a to ET-23s with the general formula where: Group ET Ar 2'< Ar 2"< Formal (ET-23a) Formal (Ar-1) Formal (Ar-1) Formal (ET-23b) Formal (Ar-16) Formal (Ar-16) Formal (ET-23c) Formal (Ar-1) Formal (Ar-16) Formal (ET-23d) Formal (Ar-63) Formal (Ar-65) Formal (ET-11pm) Formal (Ar-63) Formal (Ar-63) Formal (ET-23f) Formal (Ar-1) Formal (Ar-63) Formula (ET-23g) Formal (Ar-1) Formal (Ar-65) Formal (ET-11pm) Formal (Ar-65) Formal (Ar-65) Formal (ET-23i) Formal (Ar-1) Formal (Ar-66) Formula (ET-23j) Formal (Ar-1) Formal (Ar-274) Formal (ET-23k) Formal (Ar-1) Formal (Ar-69) Formal (ET-23l) Formal (Ar-69) Formal (Ar-69) Formal (ET-23m) Formal (Ar-1) Formal (Ar-49) Formal (ET-23n) Formal (Ar-49) Formal (Ar-49) Formal (ET-23º) Formal (Ar-1) Formal (Ar-3) Formal (ET-23p) Formal (Ar-3) Formal (Ar-3) Formula (ET-23q) Formal (Ar-66) Formal (Ar-66) Formal (ET-23r) Formal (Ar-1) Formal (Ar-139) Formula (ET-23s) Formula (Ar-139) Formula (Ar-139)

[0054] Groups ET-24a to ET-24s using the general formula where: Group ONE Ar 2'< Ar 2"< Formula (ET-24a) Formula (Ar-1) Formula (Ar-1) Formula (ET-24b) Formula (Ar-16) Formula (Ar-16) Formula (ET-24c) Formula (Ar-1) Formula (Ar-16) Formula (ET-24d) Formula (Ar-63) Formula (Ar-65) Formula (ET-24e) Formula (Ar-63) Formula (Ar-63) Formula (ET-24f) Formula (Ar-1) Formula (Ar-63) Formula (ET-24g) Formula (Ar-1) Formula (Ar-65) Formula (ET-24h) Formula (Ar-65) Formula (Ar-65) Formula (ET-24i) Formula (Ar-1) Formula (Ar-66) Formula (ET-24j) Formula (Ar-1) Formula (Ar-274) Formula (ET-24k) Formula (Ar-1) Formula (Ar-69) Formula (ET-24l) Formula (Ar-69) Formula (Ar-69) Formula (ET-24m) Formula (Ar-1) Formula (Ar-49) Formula (ET-24n) Formula (Ar-49) Formula (Ar-49) Formula (ET-24o) Formula (Ar-1) Formula (Ar-3) Formula (ET-24p) Formula (Ar-3) Formula (Ar-3) Formula (ET-24q) Formula (Ar-66) Formula (Ar-66) Formula (ET-24r) Formula (Ar-1) Formula (Ar-139) Formula (ET-24s) Formula (Ar-139) Formula (Ar-139)

[0055] Groups ET-25a to ET-25s using the general formula where: Group ONE Ar 2'< Ar 2"< Formula (ET-25a) Formula (Ar-1) Formula (Ar-1) Formula (ET-25b) Formula (Ar-16) Formula (Ar-16) Formula (ET-25c) Formula (Ar-1) Formula (Ar-16) Formula (ET-25d) Formula (Ar-63) Formula (Ar-65) Formula (ET-25e) Formula (Ar-63) Formula (Ar-63) Formula (ET-25f) Formula (Ar-1) Formula (Ar-63) Formula (ET-25g) Formula (Ar-1) Formula (Ar-65) Formula (ET-25h) Formula (Ar-65) Formula (Ar-65) Formula (ET-25i) Formula (Ar-1) Formula (Ar-66) Formula (ET-25j) Formula (Ar-1) Formula (Ar-274) Formula (ET-25k) Formula (Ar-1) Formula (Ar-69) Formula (ET-25l) Formula (Ar-69) Formula (Ar-69) Formula (ET-25m) Formula (Ar-1) Formula (Ar-49) Formula (ET-25n) Formula (Ar-49) Formula (Ar-49) Formula (ET-25o) Formula (Ar-1) Formula (Ar-3) Formula (ET-25p) Formula (Ar-3) Formula (Ar-3) Formula (ET-25q) Formula (Ar-66) Formula (Ar-66) Formula (ET-25r) Formula (Ar-1) Formula (Ar-139) Formula (ET-25s) Formula (Ar-139) Formula (Ar-139)

[0056] Groups ET-26a to ET-26k using the general formula where: Group ONE Ar 2< Formula (ET-26a) Formula (Ar-1) Formula (ET-26b) Formula (Ar-16) Formula (ET-26c) Formula (Ar-3) Formula (ET-26d) Formula (Ar-49) Formula (ET-26e) Formula (Ar-63) Formula (ET-26f) Formula (Ar-65) Formula (ET-26g) Formula (Ar-66) Formula (ET-26h) Formula (Ar-69) Formula (ET-26i) Formula (Ar-78) Formula (ET-26i) Formula (Ar-139) Formula (ET-26k) Formula (Ar-274)

[0057] Groups ET-27a to ET-27k using the general formula where: Group ONE Ar 2< Formula (ET-27a) Formula (Ar-1) Formula (ET-27b) Formula (Ar-16) Formula (ET-27c) Formula (Ar-3) Formula (ET-27d) Formula (Ar-49) Formula (ET-27e) Formula (Ar-63) Formula (ET-27f) Formula (Ar-65) Formula (ET-27g) Formula (Ar-66) Formula (ET-27h) Formula (Ar-69) Formula (ET-27i) Formula (Ar-78) Formula (ET-27i) Formula (Ar-139) Formula (ET-27k) Formula (Ar-274)

[0058] Groups ET-28a to ET-28k using the general formula where: Group ONE Ar 2< Formula (ET-28a) Formula (Ar-1) Formula (ET-28b) Formula (Ar-16) Formula (ET-28c) Formula (Ar-3) Formula (ET-28d) Formula (Ar-49) Formula (ET-28e) Formula (Ar-63) Formula (ET-28f) Formula (Ar-65) Formula (ET-28g) Formula (Ar-66) Formula (ET-28h) Formula (Ar-69) Formula (ET-28i) Formula (Ar-78) Formula (ET-28i) Formula (Ar-139) Formula (ET-28k) Formula (Ar-274)

[0059] Preferably, R 3< is selected in each instance as the same or different from H, D, F, CN, Si(R 5< ) 3 , N(R 5< ) 2 , straight-chain alkyl or alkoxy groups with 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups with 3 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms; wherein the aforementioned alkyl and alkoxy groups, the aforementioned aromatic ring systems and the aforementioned heteroaromatic ring systems are each substituted with R 5< residues; and wherein in the aforementioned alkyl or alkoxy groups one or more CH 2 groups may be replaced by -C=C-, -R 5< C=CR 5< -, Si(R 5< ) 2 , C=O, C=NR 5< , -NR 5< -, -O-, -S-, -C(=O)O- or -C(=O)NR 5< -.

[0060] Particularly preferably, R3 is selected, in each instance, as the same or different from H, D, Si(R5)3, straight-chain alkyl groups with 1 to 20 carbon atoms, which may be deuterated, branched or cyclic alkyl groups with 3 to 20 carbon atoms, which may be deuterated, aromatic ring systems with 6 to 40 aromatic ring atoms, which may be deuterated, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms, which may be deuterated, wherein the aforementioned alkyl groups, the aforementioned aromatic ring systems, and the aforementioned heteroaromatic ring systems are each substituted with R5 substituents, which are preferably equal to H. Most preferably, R3 is equal to H.

[0061] Preferably, R 5< is selected in each instance as the same or different from H, D, F, CN, Si(R 6< ) 3 , straight-chain alkyl or alkoxy groups with 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups with 3 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms; wherein the aforementioned alkyl and alkoxy groups, the aforementioned aromatic ring systems and the aforementioned heteroaromatic ring systems are each substituted with R 6< residues; and wherein in the aforementioned alkyl or alkoxy groups one or more CH 2 groups may be replaced by -C≡C-, -R 6< C=CR 6< -, Si(R 6< ) 2 , C=O, C=NR 6< , -NR 6< -, -O-, - S-, -C(=O)O- or -C(=O)NR 6< -.Particularly preferably, R5 is selected, in each occurrence, as either the same or different from H, D, Si(R6)3, straight-chain alkyl groups with 1 to 20 carbon atoms, which may be deuterated, branched or cyclic alkyl groups with 3 to 20 carbon atoms, which may be deuterated, aromatic ring systems with 6 to 40 aromatic ring atoms, which may be deuterated, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms, which may be deuterated, wherein the aforementioned alkyl groups, the aforementioned aromatic ring systems, and the aforementioned heteroaromatic ring systems are each substituted with R6 substituents, which are preferably equal to H. R5 is most preferably equal to H.

[0062] In a preferred embodiment of the invention, the two residues R 0< are not linked together and do not form an aliphatic or heteroaliphatic ring, so that no spiro compound, in particular no spirobifluorene derivative, is formed at position 8 of the fluorene derivative.

[0063] Accordingly, in a preferred embodiment of the invention, formula (I) corresponds to the following formula (IA) where the variables are defined as above for formula (I) and at least one group A as defined above exists for each formula; and R 4< is chosen the same or different from H, D, F, Cl, Br, in each occurrence. I,C(=O)R 1< , CN, Si(R 1< )3, N(R 1< ) 2 , P(=O)(R 1< ) 2 , OR 1< , S(=O)R 1< , S(=O) 2 R 1< , straight-chain alkyl, alkoxy or thioalkyl groups with 1 to 20 C atoms, branched or cyclic alkyl, alkoxy or thioalkyl groups with 3 to 20 C atoms, alkenyl or alkynyl groups with 2 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, heteroaromatic ring systems with 5 to 40 aromatic ring atoms, aryloxy or heteroaryloxy groups with 5 to 40 aromatic ring atoms, and aralkyl groups with 5 to 40 aromatic ring atoms; wherein it is excluded that the two residues R 4< are linked together and form an aliphatic or heteroaliphatic ring; wherein the aforementioned alkyl, alkoxy, thioalkyl, alkenyl, alkynyl, aryloxy, heteroaryloxy and aralkyl groups and the aforementioned aromatic ring systems and heteroaromatic ring systems are each substituted with residues R 1<;and wherein one or more CH2 groups in the aforementioned alkyl, alkoxy, thioalkyl, alkenyl, alkynyl, aryloxy, heteroaryloxy and aralkyl groups may be replaced by -R1< C=CR1< -, -C=C-, Si(R1< )2 , C=O, C=NR1< , -C(=O)O-, -C(=O)NR1< -, NR1< , P(=O)(R1< ), -O-, -S-, SO or SO2. ;

[0064] Preferred embodiments of formula (IA) are the following formulas (II-A), (III-A) and (IV-A): where the variables are defined as above and at least one group A as defined above exists for each formula.

[0065] Preferably, R 4< is chosen to be the same or different in each occurrence from F, CN, Si(R 1< ) 3 , straight-chain alkyl groups with 1 to 20 C atoms, branched or cyclic alkyl groups with 3 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms; wherein the aforementioned alkyl groups and the aforementioned aromatic ring systems and heteroaromatic ring systems are each substituted with R 1< residues and wherein it is excluded that the two R 4< residues are linked together and form an aliphatic or heteroaliphatic ring.

[0066] For the above-mentioned formulas (II-A), (III-A), and (IV-A), the aforementioned preferred embodiments of the variable elements preferably apply. Preferably, exactly two or one group A are bound in each formula, and particularly preferably exactly one (that is, preferably one or two R1< groups, or one or two Ar1< groups, or one R1< group and one Ar1< group are replaced accordingly by one or two groups A, respectively). If two groups A are present in the compounds of formulas (II-A), (III-A), and (IV-A), they can either both be bound to the heteroaromatic five-membered ring; or one group A is bound to the heteroaromatic five-membered ring and the other group A is bound to the benzene ring (aromatic six-membered ring); or both groups A are bound to the benzene ring. Preferably, one or both groups A are bound to the heteroaromatic five-membered ring.The preferred bonding positions on the benzene ring of the fluorene derivative framework are positions 4 and 6. If no group A is bonded to the heteroaromatic five-membered ring, both groups Ar1< can be H, or one group Ar1< can be H and the other a residue as defined above, or both groups Ar1< can be the same or different from the residues defined above. If a group A is bonded to the heteroaromatic five-membered ring, one of the groups Ar1< can be either H or a residue as defined above. In the formulas mentioned above, X is preferably S or O, and particularly preferably S. Among the formulas mentioned above, formulas (II-A) and (IV-A) are preferred, especially formula (II-A).

[0067] Furthermore, in the above-mentioned formulas (II-A), (III-A) and (IV-A), all R1< substituents bonded to the benzene ring are preferably equal to H. According to a further preferred embodiment, in the above-mentioned formulas (II-A), (III-A) and (IV-A), in addition to the present group(s) A, exactly two R1< substituents bonded to the benzene ring, particularly preferably exactly one, are not equal to H, especially when the group(s) A is / are bonded to the heteroaromatic five-membered ring. The preferred bonding positions of the R1< substituents that are not equal to H are positions 4 and 6 on the benzene ring of the fluorene derivative framework, but of course only if these positions are not occupied by the group(s) A. In the case that R 1< is not equal to H, particularly preferred groups R 1< are the groups defined above (R 1< -1), (R 1< -8), (R 1< -31), (R 1< -33), (R 1< -163), (R 1< -189) and (R 1< -190).

[0068] According to a further preferred embodiment of the invention, R 4< is selected identically in every instance. Particularly preferably, R 4< in the above-mentioned formulas is selected identically in every instance from straight-chain alkyl groups with 1 to 20 carbon atoms, branched or cyclic alkyl groups with 3 to 20 carbon atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms, wherein the aforementioned alkyl groups, aromatic ring systems, and heteroaromatic ring systems are each substituted with R 1< groups, and wherein it is excluded that the two R 4< groups are linked together and form an aliphatic or heteroaliphatic ring. Particularly preferred are both residues R 4< being chosen to be straight-chain alkyl groups with 1 to 4 C atoms and phenyl, each of which is substituted with residues R 1<, where R 1< is preferably H in this case.

[0069] According to another further preferred embodiment of the invention, R 4< is selected differently in each instance. Particularly preferably, in the above-mentioned formulas, R 4< is selected differently in each instance from straight-chain alkyl groups with 1 to 20 carbon atoms, branched or cyclic alkyl groups with 3 to 20 carbon atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms, wherein the aforementioned alkyl groups, aromatic ring systems, and heteroaromatic ring systems are each substituted with R 1< groups, and wherein it is excluded that the two R 4< groups are linked together and form an aliphatic or heteroaliphatic ring.Particularly preferred are both residues R 4< being selected differently from a straight-chain alkyl group with 1 to 4 C atoms and phenyl, each of which is substituted with residues R 1<, where R 1< is preferably H in this case.

[0070] Preferred embodiments of formulas (II-A), (III-A) and (IV-A) correspond to the following formulas: Formula (II-A-S1) Formula (II-A-S2) Formula (II-A-S3) Formula (II-A-S4) Formula (II-A-S5) Formula (II-A-S6) Formula (II-A-O1) Formula (II-A-O2) Formula (II-A-O3) Formula (II-A-O4) Formula (II-A-O5) Formula (II-A-O6) Formula (II-A-S7) Formula (II-A-O7) Formula (IV-A-S1) Formula (IV-A-S2) Formula (IV-A-S3) Formula (IV-A-S4) Formula (IV-A-O1) Formula (IV-A-O2) Formula (IV-A-O3) Formula (IV-A-O4) Formula (IV-A-O5) Formula (IV-A-O6) Formula (III-A-S1) Formula (III-A-S2) Formula (III-A-S3) Formula (III-A-S4) Formula (III-A-S5) Formula (III-A-S6) Formula (III-A-O3) Formula (III-A-O4) Formula (III-A-O5) Formula (III-A-O6) Formula (III-A-S7) Formula (III-A-O7) where the variables have the above-mentioned meanings and correspond to their above-mentioned preferred forms of execution.

[0071] In the cases in the group

[0072] Among the above formulas are the formulas (II-A-S1) to (IV-AS1), (II-A-S2) to (IV-A-S2), (II-A-S4) to (IV-A-S4), (II-A-S6) to (IV-A-S6), (II-A-O1) to (IV-A-S6), (II-A-O1) to (IV-A-O1), (II-A-O1) to (II-O-O) (IV-A-O2), (II-A-O4) to (IV-A-O4) and (II-A-O6) to (IV-A-O6) particularly favored. Particularly favored are the formulas (II-A-S1) to (IV-A-S1), (II-A-S2) to (IV-A-S2), (II-A-S4) to (IV-A-S4), (II-A-O1) to (IV-A-O1), (II-A-O2) to (IV-A-O1) and (II-A-O2) to (IV-A-4-A) and (II-A-O) bis (IV-A-O4).

[0073] Further particularly favored are the formulas (II-A-S1), (IV-A-S1), (II-A-S2), (IV-A-S2), (II-A-S4), (IV-A-S4), (II-A-S6), (IV-A-S6), (II-A-O1), (IV-A-O1), (IV-A-O), (IV-A-O), (IV-A-O), (IV-A-O), (IV-A-O1), (II-A-O4), (IV-A-O4), (II-A-O6) and (IV-A-O6).

[0074] The most commonly preferred among the above formulas are the formulas (II-A-S1), (IV-A-S1), (II-A-S2), (IV-A-S2), (II-A-S4), (IV-A-S4), (II-A-O1), (IV-A-O1), (II-A-O1), (II-A-O1), (II-A-O1), (II-A-O1), (II-A-O1), (II-O-O2), (II-O-O2) and (IV-A-O4).

[0075] In particular, the reported measured connection corresponds to a formula (II-A-S1) to (IV-A-S1), (II-A-S2) to (IV-A-S2), (II-A-S4) to (IV-A-S4), (II-A-S6) to (IV-A-S6), (II-A-S6) to (II-A-O) to (IV-A-O1), (II-A-O2) to (IV-A-O2), (II-A-O4) to (IV-A-O4) or (II-A-O6) to (IV-A-O6), where for the following Variables applies: Ar 1< is chosen, in each occurrence, to be the same or different from phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, fluorenyl, in particular 9,9'-dimethylfluorenyl and 9,9'-diphenylfluorenyl, benzofluorenyl, spirobifluorenyl, indenofluorenyl, indenocarbazolyl, dibenzofuranyl, dibenzothiophenyl, benzofuranyl, benzothiophenyl, benzocondensed dibenzofuranyl, benzocondensed dibenzothiophenyl, naphthyl-substituted phenyl, fluorenyl-substituted phenyl, spirobifluorenyl-substituted phenyl, dibenzofuranyl-substituted phenyl, dibenzothiophenyl-substituted phenyl, carbazolyl-substituted phenyl, pyridyl-substituted phenyl, pyrimidyl-substituted phenyl, triazinyl-substituted Phenyl, wherein the aforementioned groups are each substituted with residues R 2<, and H;R 1< is chosen in each occurrence as the same or different from H, D, Si(R 5< ) 3 , straight-chain alkyl groups with 1 to 20 C atoms, which may be deuterated, branched or cyclic alkyl groups with 3 to 20 C atoms, which may be deuterated, aromatic ring systems with 6 to 40 aromatic ring atoms, which may be deuterated, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms, which may be deuterated, wherein the aforementioned alkyl groups, the aforementioned aromatic ring systems and the aforementioned heteroaromatic ring systems are each substituted with R 5< residues, which are preferably equal to H;R 4< is chosen to be the same or different in each occurrence and consists of straight-chain alkyl groups with 1 to 20 C atoms, branched or cyclic alkyl groups with 3 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms, wherein the aforementioned alkyl groups, aromatic ring systems, and heteroaromatic ring systems are each substituted with R 1< residues, and wherein it is excluded that the two R 4< residues are linked together and form an aliphatic or heteroaliphatic ring; A is a unit of formula (A) ;

[0076] Formula (A), where the variables in Formula (A) are defined as follows: Ar L< is chosen in each occurrence, either the same or different, from divalent groups derived from benzene, biphenyl, terphenyl, naphthalene, fluorene, indenofluorene, indenocarbazole, spirobifluorene, dibenzofuran, and dibenzothiophene, each substituted with R 2< residues; ET is chosen in each occurrence, either the same or different, from groups derived from pyridine, pyrazine, pyrimidine, pyridazine, 1,2,4-triazine, 1,3,5-triazine, quinoline, isoquinoline, quinoxaline, quinazoline, pyrazole, imidazole, benzimidazole, thiazole, benzothiazole, oxazole, oxadiazole, and benzooxazole, each substituted with Ar 2< groups;Ar 2< is chosen, in each occurrence, as the same or different from phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, fluorenyl, in particular 9,9'-dimethylfluorenyl and 9,9'-diphenylfluorenyl, benzofluorenyl, spirobifluorenyl, indenofluorenyl, indenocarbazolyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, benzofuranyl, benzothiophenyl, benzo-condensed dibenzofuranyl, benzo-condensed dibenzothiophenyl, naphthyl-substituted phenyl, fluorenyl-substituted phenyl, spirobifluorenyl-substituted phenyl, dibenzofuranyl-substituted phenyl, dibenzothiophenyl-substituted phenyl, carbazolyl-substituted phenyl, pyridyl-substituted phenyl, pyrimidyl-substituted phenyl. Triazinyl-substituted phenyl, wherein the aforementioned groups are each substituted with R 3< residues, and H; ; n = 1 oder 0 ; and the other variables are defined according to their broadest embodiment specified above, preferably the preferred embodiments specified above.

[0077] Preferred compounds of formula (I) according to this embodiment are shown in Table 1 below.

[0078] In another preferred embodiment of the invention, the two residues R 0< are linked together and form an aliphatic or heteroaliphatic ring, such that a spiro compound, in particular a spirobifluorene derivative, is formed at position 8 of the fluorene derivative.

[0079] Accordingly, in another preferred embodiment of the invention, formula (I) corresponds to the following formula (IB): where W is chosen from N and CR 1< at each occurrence, either the same or different; U is chosen from O and S; k is equal to 0 or 1, where in the case k=0 the relevant heteroatom U is omitted and U is instead a single bond connecting the corresponding two aromatic six-membered rings; and the variables Z, Y and R 1< are defined above, and where at least one group A is present in formula (IB) as defined above.

[0080] Preferably, at most three groups W in formula (IB) are present; particularly preferably at most two groups W; very preferably at most one group W; most preferably no group W in an aromatic six-membered ring is equal to N. The remaining groups are accordingly equal to CR 1< . Furthermore, it is preferred that adjacent groups W in an aromatic six-membered ring are not equal to N. It is again preferred that at most three groups W in a formula (IB) are equal to N; particularly preferably at most two groups W in a formula (IB) are equal to N; very preferably at most one group W in a formula (IB) is equal to N; most preferably no group W is equal to N.

[0081] Preferred embodiments of formula (IB) correspond to the following formulas (II-B) to (IV-B) and (II-C) to (IV-C): Formula (II-B) Formula (III-B) Formula (IV-B) Formula (II-C) Formula (III-C) Formula (IV-C) where the variables are defined as above and the free positions on the benzene rings are each represented by R groups. 1 are substituted, and wherein at least one group A as defined above is present in each formula, wherein in the above-mentioned formulas preferably exactly one group A is bonded in each formula, which either bonds to one of the benzene rings (that is, a residue R) 1 is accordingly replaced by a group A), or to the heteroaromatic five-membered ring (that is, a group Ar) 1 (is accordingly replaced by a group A), it is particularly preferred if group A binds to the heteroaromatic five-membered ring. The preferred binding positions on the benzene rings of the spirobifluorene derivative backbone are positions 4, 6, 9, 11, 12 and 14. In the case that no group A is bound to the heteroaromatic five-membered ring, both groups Ar 1 equal to H, or a group Ar 1 is H, the other a remainder as defined above, or both groups Ar 1 They can be chosen from the residues defined above, either the same or different. If a group A is bonded to the heteroaromatic five-membered ring, one group Ar can be... 1 X should either be equal to H or a remainder as defined above. In the formulas above, X is preferably equal to S or O, and particularly preferably equal to S.

[0082] Furthermore, in the above-mentioned formulas (II-B) to (IV-B) and (II-C) to (IV-C), all residues R 1< equal to H that are bonded to the benzene rings are preferred.

[0083] According to a further preferred embodiment, in the above-mentioned formulas (II-B) to (IV-B) and (II-C) to (IV-C), in addition to the at least one group A, exactly two residues R 1< are bonded to the benzene rings, and particularly preferably exactly one residue R 1<, other than H, is included, especially when the at least one group A is bonded to the heteroaromatic five-membered ring. The preferred bonding positions for residues R 1<, other than H, are positions 4, 6, 9, 11, 12, and 14 on the benzene rings of the spirobifluorene derivative skeleton, and of course only if these positions are not occupied by the at least one group A. In the case that R 1< is not equal to H, particularly preferred groups R 1< are the groups defined above (R 1< -1), (R 1< -8), (R 1< -31), (R 1< -33), (R 1< -163), (R 1< -189) and (R 1< -190).

[0084] Preferably, k equals 0. Accordingly, among the formulas mentioned above, formulas (II-B) to (IV-B) are preferred, in particular formula (II-B).

[0085] Preferred embodiments of formulas (II-B) to (IV-B) correspond to the following formulas: Formula (II-B-S1) Formula (II-B-S2) Formula (II-B-S3) Formula (II-B-S4) Formula (II-B-S5) Formula (II-B-O1) Formula (II-B-O2) Formula (II-B-O3) Formula (II-B-O4) Formula (II-B-O5) Formula (II-B-N1) Formula (II-B-N2) Formula (II-B-N3) Formula (II-B-N4) Formula (II-B-N5) Formula (III-B-S1) Formula (III-B-S2) Formula (III-B-S3) Formula (III-B-S4) Formula (III-B-S5) Formula (III-B-O1) Formula (III-B-O2) Formula (III-B-O3) Formula (III-B-O4) Formula (III-B-O5) Formula (III-B-N1) Formula (III-B-N2) Formula (III-B-N3) Formula (III-B-N4) Formula (III-B-N5) Formula (IV-B-S1) Formula (IV-B-S2) Formula (IV-B-S3) Formula (IV-B-S4) Formula (IV-B-S5) Formula (IV-B-O1) Formula (IV-B-O2) Formula (IV-B-O3) Formula (IV-B-O4) Formula (IV-B-O5) Formula (IV-B-N1) Formula (IV-B-N2) Formula (IV-B-N3) Formula (IV-B-N4) Formula (IV-B-N5), wherein the variables have the above-mentioned meanings and preferably correspond to their above-mentioned preferred embodiments, and wherein the free positions on the benzene rings are each occupied by residues R 1 are substituted, which are preferably equal to H.

[0086] In the above-mentioned formulas, Ar 0< is preferably phenyl substituted with R 2< groups, where R 2< is preferably H in these cases.

[0087] Among the above-mentioned formulas are the formulas (II-B-S1) to (II-B-S4), (II-B-N1) to (II-B-N4) and (II-B-O1) to (II-B-O4), (III-B-S1) to (III-B-S4), (III-B-N1) to (III-B-N4) and (III-B-N1) to (B-N4) and (III-B-O1) to (III-B-O4), and (IV-B-S1) to (IV-B-S4), (IV-B-N1) to (IV-B-N4) and (IV-B-O1) to (IV-B-O4). Particularly favored are the formulas (II-B-S1) to (II-B-S4) and (II-B-O1) to (II-B-O4), (III-B-S1) to (III-B-S4) and (III-B-O1) to (III-B-O4), and (IV-B-S1 to (IV-B-S4) and (IV-B-S4) and (IV-B-O1) (IV-B-O1) to (IV-B-O4). Particularly favored are the formulas (II-B-S1) to (II-B-S4) and (II-B-O1) to (II-B-O4).

[0088] Further particularly favored are the formulas (II-B-S1) to (II-B-N1) and (II-B-S2) to (II-B-N2).

[0089] The most preferred formulas are (II-B-S1), (II-B-O1), (II-B-S2) and (II-B-O2).

[0090] Also particularly preferred are the formulas (II-B-S1), (II-B-S2), (II-B-S3), (II-B-S4), (II-B-O1), (II-B-O2), (II-B-O3), (II-B-O4), (III-B-S1), (III-B-S2), (III-B-S3), (III-B-S4), (III-B-O1), (III-B-O2), (III-B-O3), (III-B-O4), (IV-B-S1), (IV-B-S2), (IV-B-S3), (IV-B-S4), (IV-B-O1), (IV-B-O2), (IV-B-O3), (IV-B-O4), (II-B-N1) and (II-B-N2).

[0091] Preferred embodiments of formulas (II-B-S3), (II-B-S4), (III-B-S3), (III-B-S4), (IV-B-S3) and (IV-B-S4) are the following formulas: Formula (II-B-S3-1) Formula (II-B-S3-2) Formula (II-B-S4-1) Formula (II-B-S4-2) Formula (III-B-S3-1) Formula (III-B-S3-2) Formula (III-B-S4-1) Formula (III-B-S4-2) Formula (IV-B-S3-1) Formula (IV-B-S3-2) Formula (IV-B-S4-1) Formula (IV-B-S4-2), wherein the variables occurring are defined as above and preferably correspond to their preferred embodiments, and wherein the free positions on the benzene rings are each occupied by residues R 1 are substituted, which are preferably equal to H.

[0092] Preferred embodiments of formulas (II-B-O3), (II-B-O4), (III-B-O3), (III-B-O4), (IV-B-O3) and (IV-B-O4) are the following formulas: Formula (II-B-O3-1) Formula (II-B-O3-2) Formula (II-B-O4-1) Formula (II-B-O4-2) Formula (III-B-O3-1) Formula (III-B-O3-2) Formula (III-B-O4-1) Formula (III-B-O4-2) Formula (IV-B-O3-1) Formula (IV-B-O3-2) Formula (IV-B-O4-1) Formula (IV-B-O4-2), wherein the variables occurring are defined as above and preferably correspond to their preferred embodiments, and wherein the free positions on the benzene rings are each occupied by residues R 1 are substituted, which are preferably equal to H.

[0093] Among the formulas mentioned above, the formulas (II-B-S3-1), (II-B-S3-2), (II-B-S4-1) (II-B-S4-2), (II-B-O3-1), (II-B-O3-2), (II-B-O4-1) (II-B-O4-2) are particularly preferred.

[0094] Most preferably, compounds of formula (I) in this embodiment correspond to one of the formulas (II-B-S1), (II-B-O1), (II-B-S2), (II-B-O2), (II-B-S3-1), (II-B-S3-2), (II-B-S4-1) (II-B-S4-2), (II-B-O3-1), (II-B-O3-2), (II-B-O4-1) and (II-B-O4-2), wherein the variables in these cases preferably correspond to their preferred embodiments specified above.

[0095] The compound according to the application therefore particularly preferably corresponds to a formula (II-B-S1), (II-B-S2), (II-B-S3), (II-B-S4), (II-B-O1), (II-B-O2), (II-B-O3), (II-B-O4), (III-B-S1), (III-B-S2), (III-B-S3), (III-B-S4), (III-B-O1), (III-B-O2), (III-B-O3), (III-B-O4), (IV-B-S1), (IV-B-S2), (IV-B-S3), (IV-B-S4), (IV-B-O1), (IV-B-O2), (IV-B-O3), (IV-B-O4), (II-B-N1) and (II-B-N2), where for the occurring Variables apply: Ar 1< is chosen, in each occurrence, to be the same or different from phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, fluorenyl, in particular 9,9'-dimethylfluorenyl and 9,9'-diphenylfluorenyl, benzofluorenyl, spirobifluorenyl, indenofluorenyl, indenocarbazolyl, dibenzofuranyl, dibenzothiophenyl, benzofuranyl, benzothiophenyl, benzocondensed dibenzofuranyl, benzocondensed dibenzothiophenyl, naphthyl-substituted phenyl, fluorenyl-substituted phenyl, spirobifluorenyl-substituted phenyl, dibenzofuranyl-substituted phenyl, dibenzothiophenyl-substituted phenyl, carbazolyl-substituted phenyl, pyridyl-substituted phenyl, pyrimidyl-substituted phenyl, triazinyl-substituted Phenyl, wherein the aforementioned groups are each substituted with residues R 2<, and H;R 1< is chosen in each occurrence as the same or different from H, D, Si(R 5< ) 3 , straight-chain alkyl groups with 1 to 20 C atoms, which may be deuterated, branched or cyclic alkyl groups with 3 to 20 C atoms, which may be deuterated, aromatic ring systems with 6 to 40 aromatic ring atoms, which may be deuterated, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms, which may be deuterated, wherein the aforementioned alkyl groups, the aforementioned aromatic ring systems and the aforementioned heteroaromatic ring systems are each substituted with R 5< residues, which are preferably equal to H;R 4< is chosen to be the same or different in each occurrence and consists of straight-chain alkyl groups with 1 to 20 C atoms, branched or cyclic alkyl groups with 3 to 20 C atoms, aromatic ring systems with 6 to 40 aromatic ring atoms, and heteroaromatic ring systems with 5 to 40 aromatic ring atoms, wherein the aforementioned alkyl groups, aromatic ring systems, and heteroaromatic ring systems are each substituted with R 1< residues, and wherein it is excluded that the two R 4< residues are linked together and form an aliphatic or heteroaliphatic ring; A is a unit of formula (A) ; Formula (A), where the variables in formula (A) are defined as follows: Ar L< is chosen, in each occurrence, to be the same or different from divalent groups derived from benzene, biphenyl, terphenyl, naphthalene, fluorene, indenofluorene, indenocarbazole, spirobifluorene, dibenzofuran, and dibenzothiophene, each substituted with R 2< residues; ET is chosen, in each occurrence, to be the same or different from groups derived from pyridine, pyrazine, pyrimidine, pyridazine, 1,2,4-triazine, 1,3,5-triazine, quinoline, isoquinoline, quinoxaline, quinazoline, pyrazole, imidazole, benzimidazole, thiazole, benzothiazole, oxazole, oxadiazole, and benzooxazole, each substituted with Ar 2< groups;Ar 2< is chosen, in each occurrence, as the same or different from phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, fluorenyl, in particular 9,9'-dimethylfluorenyl and 9,9'-diphenylfluorenyl, benzofluorenyl, spirobifluorenyl, indenofluorenyl, indenocarbazolyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, benzofuranyl, benzothiophenyl, benzo-condensed dibenzofuranyl, benzo-condensed dibenzothiophenyl, naphthyl-substituted phenyl, fluorenyl-substituted phenyl, spirobifluorenyl-substituted phenyl, dibenzofuranyl-substituted phenyl, dibenzothiophenyl-substituted phenyl, carbazolyl-substituted phenyl, pyridyl-substituted phenyl, pyrimidyl-substituted phenyl. Triazinyl-substituted phenyl, wherein the aforementioned groups are each substituted with R 3< residues, and H; n = 1 or 0; and the further variables are defined according to their broadest embodiment specified above, preferably the preferred embodiments specified above.

[0096] Preferred compounds of formula (I) according to this embodiment are shown in the following Table 1:

[0097] The compounds described in the application can be produced using synthesis steps of organic chemistry known to those skilled in the art, for example by metallation, addition of nucleophiles to carbonyl groups, Suzuki reaction and Hartwig-Buchwald reaction.

[0098] Preferred methods for producing the compounds according to the application are shown below. These methods are to be understood as examples and not as limiting. A person skilled in the art may deviate from the exemplary methods shown and make modifications within the scope of their general technical knowledge if this is technically advantageous in order to obtain the compounds according to the application.

[0099] According to a preferred method, in a first step a heteroaromatic five-membered ring (particularly preferably pyrrole, furan or thiophene) bearing a carboxylic acid group or a carboxylic ester group is coupled to a benzene ring in a Suzuki reaction (Scheme 1). Alternatively, the carboxylic acid or carboxylic ester group can also be bonded to the benzene ring.

[0100] The variables are defined as follows: V is chosen as the same or different from reactive groups, preferably Cl, Br or I, for each occurrence; X is chosen as the same or different from S, O, NAr 0< , CH and CV, wherein Ar 0< is defined as in formula (I) and preferably exactly two X, particularly preferably exactly one X is chosen from S, O and NAr 0< ; Hal is Cl, Br or I; E is a reactive group, preferably a boronic acid group or a boron ester group; and f is 0, 1 or 2; wherein the compounds at the free positions on the benzene ring are each substituted with a residue R 1< , as defined above for formula (I), and wherein at least one group V is present.

[0101] The compounds obtained according to Scheme 1 are prepared by ring closure reaction under acidic conditions according to a formula (Int-1) (Scheme 2).

[0102] The variables are defined as for Scheme 1. To prepare the fluorene derivatives according to formula (I) or formula (IA), in which one benzene ring is exchanged for a heteroaryl five-membered ring (particularly preferably a pyrrole, furan, or thiophene ring), the compounds of formula (Int-1) are reduced to compounds of formula (Int-2), for example, by adding a solution of hydrazine in the presence of Raney nickel as a catalyst. In a subsequent step, the compounds of formula (Int-2) are converted to intermediate compounds of formula (Int-3) by adding an organohalogen compound or an organometallic reagent, preferably a Grignard reagent (Scheme 3).

[0103] The variables are defined as for Scheme 1, where R 4< is defined as above for Formula (IA).

[0104] To introduce at least one group A to the heteroaryl five-membered ring and / or the benzene ring, the compound of formula (Int-3) is coupled to at least one group A (Hal-A) in a Suzuki reaction, after conversion of the corresponding group(s) V into one or more reactive groups E, which are preferably a boronic acid group or a boron ester group. Optionally, one or two groups Ar 1< can also be attached to the heteroaryl five-membered ring (if X equals CV), preferably by Suzuki reaction. This yields compounds according to formula (IA), as shown in Scheme 4:

[0105] The variables are defined as above for formula (IA), where index g is 1 or 2, preferably 1, and where the formulas at the free positions on the benzene ring are each substituted with a residue R 1<.

[0106] To prepare the spirobifluorene derivatives according to formula (I) or formula (IB), in which a benzene ring is exchanged for a heteroaryl five-membered ring (particularly preferably a pyrrole, furan or thiophene ring), the compounds of formula (Int-1) are reacted in a subsequent step, e.g. by addition of orthohalogenated or ortho-metallated bisaryl to the carbonyl function of the compounds of formula (Int-1) and subsequent acid-catalyzed ring closure, giving compounds of formula (Int-4) (Scheme 5).

[0107] The variables are defined in the compounds of formula (Int-4) as above, wherein index f is preferably equal to 0 or 1 and index k is equal to 0 or 1, preferably equal to 0, and wherein at least one group V is present, and wherein the formulas at the free positions on the benzene rings are each substituted with a residue R 1<.

[0108] To introduce at least one group A to the heteroaryl five-membered ring and / or the benzene rings, the compound of formula (Int-4) is coupled to at least one group A (Hal-A) in a Suzuki reaction, after conversion of the corresponding group(s) V into one or more reactive groups E, which are preferably a boronic acid group or a boron ester group. Optionally, one or two groups Ar 1< can also be attached to the heteroaryl five-membered ring (if X equals CV), preferably by Suzuki reaction. This yields compounds according to formula (IB), as shown in Scheme 6:

[0109] The variables are defined as above for formula (IB), where index g is 1 or 2, preferably 1, and where the formulas at the free positions on the benzene rings are each substituted with a residue R 1<.

[0110] As shown in Schemes 4 and 6 above, the intermediates of formulas (Int-3) and (Int-4) can be reacted via a Suzuki coupling with a heteroaryl compound corresponding to group A (Hal-A). This yields compounds according to formula (I).

[0111] The subject matter of the present application is thus a process for the preparation of a fluorene derivative of formula (I), in particular of formulas (IA), or of a spirobifluorene derivative of formula (I), in particular of formula (IB), characterized in that in a first step a Suzuki coupling is carried out in which a heteroaromatic five-membered ring is coupled to a benzene ring, wherein the heteroaromatic five-membered ring or the benzene ring bears a carboxylic acid group; that in a second step the carboxylic acid group is cyclized by ring closure reaction under acidic conditions to form a bridging carbonyl group between the heteroaromatic five-membered ring and the benzene ring;that in a third step the carbonyl group is reduced and, upon addition of an organohalogen compound or an organometallic reagent, a substituted methylene bridge is obtained between the heteroaromatic five-membered ring and the benzene ring, and that in a fourth step a Suzuki coupling with a heteroaryl compound is carried out, yielding a compound of formula (I), in particular formula (IA); or that in a third step an ortho-halogenated or ortho-metallated bisaryl is added and a further ring-closure reaction is carried out; and that in a fourth step a Suzuki coupling with a heteroaryl compound is carried out, yielding a compound of formula (I), in particular formula (IB).

[0112] The compounds according to the invention described above, in particular compounds substituted with reactive leaving groups such as bromine, iodine, chlorine, boronic acid, or boronic esters, can be used as monomers for the production of corresponding oligomers, dendrimers, or polymers. Suitable reactive leaving groups include, for example, bromine, iodine, chlorine, boronic acids, boronic esters, amines, alkenyl or alkynyl groups with terminal C-C double or C-C triple bonds, oxiranes, oxetanes, groups that undergo a cycloaddition, for example, a 1,3-dipolar cycloaddition, such as dienes or azides, carboxylic acid derivatives, alcohols, and silanes.

[0113] A further aspect of the invention is therefore oligomers, polymers, or dendrimers containing one or more fluorene derivatives or spirobifluorene derivatives according to formula (I), formula (IA), or (IB), wherein the bond(s) to the polymer, oligomer, or dendrimer can be located at any position substituted in formula (I), (IA), or (IB) by R< 0, R< 1, R< 2, R< 3, or R< 4. Depending on the linkage of the compound according to formula (I), formula (IA), or (IB), the compound is either a side chain of the oligomer or polymer or a component of the main chain. For the purposes of this invention, an oligomer is understood to be a compound composed of at least three monomer units. A polymer, for the purposes of this invention, is understood to be a compound composed of at least ten monomer units. The polymers, oligomers or dendrimers according to the invention can be conjugated, partially conjugated or non-conjugated.The oligomers or polymers according to the invention can be linear, branched, or dendritic. In the linearly linked structures, the units according to formula (I), (IA), or (IB) can be directly linked to one another, or they can be linked to one another via a bivalent group, for example, via a substituted or unsubstituted alkylene group, via a heteroatom, or via a bivalent aromatic or heteroaromatic group. In branched and dendritic structures, for example, three or more units according to formula (I), (IA), or (IB) can be linked to form a branched or dendritic oligomer or polymer via a trivalent or higher-valent group, for example, via a trivalent or higher-valent aromatic or heteroaromatic group.

[0114] The same preferences apply to the repeating units according to formula (I) or (IA) or (IB) in oligomers, dendrimers and polymers as described above for compounds according to formula (I) or (IA) or (IB).

[0115] To produce the oligomers or polymers, the monomers according to the invention are homopolymerized or copolymerized with further monomers. Suitable and preferred comonomers are selected from fluorenes, spirobifluorenes, paraphenylenes, carbazoles, thiophenes, dihydrophenanthrenes, cis- and trans-indenofluorenes, ketones, phenanthrenes, or even several of these units. The polymers, oligomers, and dendrimers typically contain further units, for example, emitting (fluorescent or phosphorescent) units, such as vinyltriarylamines or phosphorescent metal complexes, and / or charge transport units, in particular those based on triarylamines.

[0116] The polymers, oligomers and dendrimers according to the invention have advantageous properties, in particular long lifetimes, high efficiencies and good color coordinates.

[0117] The polymers and oligomers according to the invention are generally produced by polymerization of one or more types of monomers, at least one of which leads to repeating units of formula (I), (IA), or (IB) in the polymer. Suitable polymerization reactions are known to those skilled in the art and are described in the literature. Particularly suitable and preferred polymerization reactions that lead to CC or CN linkages are the following: (A) Suzuki polymerization; (B) Yammoto polymerization; (C) Stille polymerization; and (D) HARTWIG-BUCHWALD polymerization.

[0118] How the polymerization can be carried out according to these methods and how the polymers can then be separated from the reaction medium and purified is known to those skilled in the art and is described in detail in the literature.

[0119] For processing 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 may be preferred to use mixtures of two or more solvents for this purpose. Suitable and preferred solvents include, 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, alpha-terpineol, benzothiazole, butyl benzoate, cumene, cyclohexanol, cyclohexanone, cyclohexylbenzene, decalin. Dodecyl benzene, ethyl benzoate, indane, methyl benzoate, NMP,p-Cymene, phenetol, 1,4-diisopropylbenzene, dibenzyl ether, diethylene glycol butyl methyl ether, triethylene glycol butyl methyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, diethylene glycol monobutyl ether, tripropylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 2-isopropylnaphthalene, pentylbenzene, hexylbenzene, heptylbenzene, octylbenzene, 1,1-bis(3,4-dimethylphenyl)ethane or mixtures of these solvents.

[0120] The invention therefore further relates to a formulation, in particular a solution, dispersion or emulsion, containing at least one fluorene derivative or spirobifluorene derivative according to formula (I) or (IA) or (IB), or at least one polymer, oligomer or dendrimer containing at least one unit according to formula (I) or (IA) or (IB), and at least one solvent, preferably an organic solvent. How such solutions can be prepared is known to those skilled in the art.

[0121] The compounds or polymers, oligomers and dendrimers according to the invention can further be present in a composition with at least one further compound, in particular at least one further organic or inorganic compound, which is also used in the electronic device, for example a hole injection material, hole transport material, hole blocking material, wide-band gap Material, fluorescent emitter, delayed fluorescent Material, phosphorescent emitter, host material, matrix material, electron blocking material, electron transport material and electron injection material, n-doped and p-doped.

[0122] The invention therefore further relates to a composition comprising at least one compound according to the invention or at least one polymer, oligomer or dendrimer according to the invention, and a further compound selected from hole injection materials, hole transport materials, hole blocking materials, wide-band gap Materials, fluorescent emitters, delayed fluorescent Materials, phosphorescent emitters, host materials, matrix materials, electron blocking materials, electron transport materials, and electron injection materials, n-doped and p-doped materials. Suitable examples of these additional compounds are listed below.

[0123] The compound according to formula (I) is suitable for use in an electronic device, in particular an organic electroluminescent device (OLED). Depending on the substitution, the compound of formula (I) can be used in different functions and layers. Its use as an electron-transporting material in an electron-transporting layer and / or as a matrix material in an emitting layer is preferred, especially in combination with a phosphorescent emitter.

[0124] A further object of the invention is therefore the use of a compound according to formula (I) in an electronic device. The electronic device is preferably selected from the group consisting of organic integrated circuits (OICs), organic field-effect transistors (OFETs), organic thin-film transistors (OTFTs), organic light-emitting transistors (OLETs), organic solar cells (OSCs), organic optical detectors, organic photoreceptors, organic field-quench devices (OFQDs), organic light-emitting electrochemical cells (OLECs), organic laser diodes (O-lasers), and particularly preferably organic electroluminescent devices (OLEDs).

[0125] The invention further relates to an electronic device comprising at least one connection according to formula (I). The electronic device is preferably selected from the devices mentioned above.

[0126] Particularly preferred is an organic electroluminescent device comprising an anode, a cathode, and at least one emitting layer, characterized in that at least one organic layer in the device contains at least one compound according to formula (I). A more preferred organic electroluminescent device comprising an anode, a cathode, and at least one emitting layer is characterized in that at least one organic layer in the device, selected from electron-transporting and emitting layers, contains at least one compound according to formula (I).

[0127] An electron-transporting layer is understood to be any layer arranged between the cathode and the emitting layer, preferably an electron injection layer (EIL), an electron transport layer (ETL), and a hole-blocking layer (HBL). An electron injection layer is understood to be a layer that is directly adjacent to the cathode. An electron transport layer is understood to be a layer that is located between the cathode and the emitting layer, but not directly adjacent to the cathode, and preferably not directly adjacent to the emitting layer either. A hole-blocking layer is understood to be a layer that is located between the cathode and the emitting layer and is directly adjacent to the emitting layer.

[0128] A hole-blocking layer preferably consists of an organic material with a lower energy level HOMO than the first and / or second organic matrix materials. This prevents the holes (whose injection and transport are generally the lesser problem) from migrating directly to the cathode (for this reason, the electron transport layer is often also called a hole-blocking layer).

[0129] In addition to the cathode, anode, and emitting layer, the electronic device may contain further layers. These are selected, for example, from one or more hole injection layers, hole transport layers, hole blocking layers, electron transport layers, electron injection layers, electron blocking layers, exciton blocking layers, interlayers, charge-generation layers, and / or organic or inorganic p / n junctions. It should be noted, however, that not every one of these layers is necessarily present, and the choice of layers always depends on the compounds used and, in particular, on whether the device is a fluorescent or phosphorescent electroluminescent device.

[0130] The sequence of layers of the electronic device is preferably as follows: Anode - Hole injection layer - Hole transport layer - optional further hole transport layers - optional electron blocking layer - emitting layer - optional hole blocking layer - electron transport layer - electron injection layer - cathode.

[0131] It should be noted again that not all of the mentioned layers need to be present, and / or that additional layers may be present.

[0132] The organic electroluminescent device according to the invention can contain several emitting layers. Particularly preferably, these emission layers exhibit several emission maxima between 380 nm and 750 nm, resulting in overall white emission. This means that different emitting compounds are used in the emitting layers, which can fluoresce or phosphoresce and emit blue, green, yellow, orange, or red light. Three-layer systems are particularly preferred, i.e., systems with three emitting layers, wherein one of the three layers exhibits blue emission, one of the three layers exhibits green emission, and one of the three layers exhibits orange or red emission. The compounds according to the invention are preferably present in a hole-transporting layer or in the emitting layer.It should be noted that for the generation of white light, instead of several color-emitting emitter compounds, a single emitter compound which emits in a broad wavelength range may also be suitable.

[0133] It is preferred that the compound of formula (I) is used as the electron transport material (ETM). The emitting layer can be a fluorescent or a phosphorescent layer. Preferably, the emitting layer is a blue fluorescent or a green phosphorescent layer.

[0134] If the device containing the compound of formula (I) includes a phosphorescent emitting layer, it is preferred that this layer contains two or more, preferably exactly two, different matrix materials (mixed-matrix system). Preferred embodiments of mixed-matrix systems are described in more detail below.

[0135] If the compound according to formula (I) is used as an electron transport material in an electron transport layer, an electron injection layer or a hole blocking layer, the compound can be used as a pure material, i.e. in a proportion of 100%, in the electron transport, electron injection or hole blocking layer, or it can be used in combination with one or more other compounds, preferably organic compounds.

[0136] According to a preferred embodiment, an electron transport layer containing the compound of formula (I) additionally includes one or more further electron-transporting compounds. These further electron-transporting compounds are preferably selected from the preferred embodiments of electron transport materials specified below. Most preferably, an electron transport layer contains the compound of formula (I) together with LiQ (lithium 8-quinolinolate) or a LiQ derivative as a further electron-transporting compound. In the described preferred embodiment, the compound of formula (I) and the one or more further electron-transporting compounds are preferably each present in a proportion of at least 10%, and more preferably each in a proportion of at least 20%.

[0137] According to another preferred embodiment, an electron transport layer contains the compound of formula (I) as pure material, and an electron injection layer contains one or more further electron transporting compounds, particularly preferably LiQ or a LiQ derivative.

[0138] According to a preferred embodiment, a hole-transporting layer containing the compound of formula (I) additionally includes one or more p-dotandes. According to the present invention, the p-dotandes preferably used are organic electron-accepting compounds that can oxidize one or more of the other compounds in the mixture.

[0139] Particularly preferred as p-doping compounds are quinodimethane compounds, azaindenofluorenediones, azaphenalenes, azatriphenylenes, I₂, metal halides, preferably transition metal halides, metal oxides, preferably metal oxides containing at least one transition metal or a metal of group 3, and transition metal complexes, preferably complexes of Cu, Co, Ni, Pd, and Pt with ligands containing at least one oxygen atom as a bonding site. Transition metal oxides are also preferred as doping compounds, preferably oxides of rhenium, molybdenum, and tungsten, particularly Re₂O₇, MoO₃, WO₃, and ReOs. Complexes of bismuth in the (III) oxidation state, especially bismuth(III) complexes with electron-deficient ligands, particularly carboxylate ligands, are again preferred.

[0140] The p-doping agents are preferably distributed largely uniformly throughout the p-doped layers. This can be achieved, for example, by co-evaporation of the p-doping agent and the hole transport material matrix. The p-doping agent is preferably present in a proportion of 1 to 10% in the p-doped layer.

[0141] The following compounds are particularly preferred as p-doping agents: (D-1) (D-2) (D-3) (D-4) (D-5) (D-6) (D-7) (D-8) (D-9) (D-10) (D-11) (D-12) (D-13) (D-14)

[0142] According to a preferred embodiment, the device includes a hole injection layer corresponding to one of the following embodiments: a) it contains a triarylamine and a p-doped element; or b) it contains a single electron-deficient material (electron acceptor). According to a preferred embodiment of embodiment a), the triarylamine is a mono-triarylamine, in particular one of the preferred triarylamine derivatives mentioned below.

[0143] According to a preferred embodiment of embodiment b), the electron-deficient material is a hexaazatriphenylene derivative as described in US 2007 / 0092755.

[0144] The compound of formula (I) can be contained in an electron injection layer, an electron transport layer, and / or a hole-blocking layer of the device. If the compound is present in an electron injection layer or an electron transport layer, it is preferably p-doped, that is, it is present in the layer mixed with a p-doped compound, as described above.

[0145] Preferably, the compound of formula (I) is contained in an electron transport layer and / or in a hole-blocking layer. Most preferably, the compound of formula (I) is contained in an electron transport layer. In this case, it is preferably not p-doped. Furthermore, it is more preferably not present as a single compound in the electron transport layer, but in combination with one or more other compounds, preferably with other electron transport and / or electron injection materials, and most preferably with LiQ (lithium 8-quinolinolate) or LiQ derivatives.

[0146] According to an alternative preferred embodiment, the compound of formula (I) is incorporated into an emitting layer as a matrix material in combination with one or more emitting compounds, preferably phosphorescent emitting compounds. The phosphorescent emitting compounds are preferably selected from red and green phosphorescent compounds.

[0147] In this case, the proportion of matrix material in the emitting layer is between 50.0 and 99.9 vol.%, preferably between 80.0 and 99.5 vol.% and particularly preferably between 85.0 and 97.0 vol.%.

[0148] Accordingly, the proportion of the emitting compound is between 0.1 and 50.0 vol.%, preferably between 0.5 and 20.0 vol.% and particularly preferably between 3.0 and 15.0 vol.%.

[0149] An emitting layer of an organic electroluminescent device can also contain systems comprising multiple matrix materials (mixed-matrix systems) and / or multiple emitting compounds. In this case, too, the emitting compounds are generally those compounds with the smallest proportion in the system, and the matrix materials are those compounds with the largest proportion. In some cases, however, the proportion of a single matrix material in the system may be smaller than the proportion of a single emitting compound.

[0150] It is preferred that the compounds according to formula (I) are used as a component of mixed-matrix systems, preferably for phosphorescent emitters. The mixed-matrix systems preferably comprise two or three different matrix materials, particularly preferably two different matrix materials. Preferably, one of the two materials is a material with electron-transporting properties and the other material is a material with hole-transporting properties. It is further preferred if one of the materials is selected from compounds with a large energy difference between HOMO and LUMO (wide-bandgap materials). In a mixed-matrix system, the compound of formula (I) preferably represents the matrix material with electron-transporting properties.Accordingly, when the compound of formula (I) is used as a matrix material for a phosphorescent emitter in the emitting layer of an OLED, a second matrix compound is present in the emitting layer that exhibits hole-transporting properties. It is particularly preferred that the compound of formula (I) as an electron-transporting material is present as a mixture in the EML with carbazole derivatives, especially biscarbazoles, as hole-transporting material. The two different matrix materials can be present in a ratio of 1:50 to 1:1, preferably 1:20 to 1:1, particularly preferably 1:10 to 1:1, and most preferably 1:4 to 1:1.

[0151] Preferred biscarbazoles as matrix material are those of the following formula

[0152] Particularly preferred biscarbazoles are those of the following formula s where the group R has the same meaning as the group R 0< defined above and / or in claim 1 ; Ar 4 and Ar 5 have the same meaning as the group Ar 0< defined above and / or in claim 1 .

[0153] Particularly preferred biscarbazoles are those of the following formulas

[0154] However, the desired electron-transporting and hole-transporting properties of the mixed-matrix components can also be mainly or completely combined in a single mixed-matrix component, with the other mixed-matrix component(s) fulfilling other functions.

[0155] The following material classes are preferably used in the aforementioned layers of the device: Phosphorescent emitters: The term phosphorescent emitters typically encompasses compounds in which light emission occurs through a spin-forbidden transition, for example a transition from an excited triplet state or a state with a higher spin quantum number, for example a quintet state.

[0156] Suitable phosphorescent emitters are compounds that, upon appropriate 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, and particularly preferably greater than 56 and less than 80. Compounds containing copper, molybdenum, tungsten, rhenium, ruthenium, osmium, rhodium, iridium, palladium, platinum, silver, gold, or europium are preferred as phosphorescent emitters, especially compounds containing iridium, platinum, or copper.

[0157] For the purposes of the present invention, all luminescent iridium, platinum or copper complexes are considered to be phosphorescent compounds.

[0158] In general, all phosphorescent complexes such as those used in phosphorescent OLEDs according to the prior art and as known to those skilled in the art in the field of organic electroluminescence devices are suitable for use in the devices according to the invention. Further examples of suitable phosphorescent emitters are shown in the following table: Fluorescent emitters:

[0159] Preferred fluorescent-emitting compounds are selected from the class of arylamines. For the purposes of this invention, an arylamine or aromatic amine is understood to be a compound containing three substituted or unsubstituted aromatic or heteroaromatic ring systems directly bonded to the nitrogen atom. Preferably, at least one of these aromatic or heteroaromatic ring systems is a condensed ring system, particularly preferably with at least 14 aromatic ring atoms. Preferred examples include aromatic anthracene, aromatic anthracenediamine, aromatic pyrene, aromatic pyrenediamine, aromatic chrysene, or aromatic chrysenediamine. An aromatic anthracene is understood to be a compound in which a diarylamine group is directly bonded to an anthracene group, preferably at position 9.An aromatic anthracenediamine is defined as a compound in which two diarylamine groups are directly bonded to an anthracene group, preferably at the 9,10 position. Aromatic pyrenamines, pyrenediamines, chrysenamines, and chrysenediamines are defined analogously, wherein the diarylamine groups are preferably bonded to the pyrene at the 1-position or the 1,6-position, respectively. Further preferred emitting compounds are indenofluorenamines or diamines, benzoindenofluorenamines or diamines, and dibenzoindenofluorenamines or diamines, as well as indenofluorene derivatives with fused aryl groups. Pyrene arylamines are also preferred. Benzoindenofluorene amines, benzofluorene amines, extended benzoindenofluorenes, phenoxazines, and fluorene derivatives linked to furan or thiophene units are also preferred. Delayed fluorescent materials:

[0160] Suitable delayed fluorescent materials, such as delayed fluorescent emitters or delayed fluorescent hosts, are well known in the prior art, e.g., in Ye Tao et al., Adv. Mater. 2014, 26, 7931-7958, MY Wong et al., Adv. Mater. 2017, 29, 1605444, WO 2011 / 070963, WO 2012 / 133188, WO 2015 / 022974 and WO 2015 / 098975. Typically, delayed fluorescent materials are characterized by having a relatively small energy gap between the singlet energy level (S1) and the triplet energy level (T1). Preferably ΔE ST is less than 0.5 eV, particularly preferably less than 0.3 eV and most preferably less than 0.2 eV, where ΔE ST represents the energy difference between the singlet energy level (S 1 ) and the triplet energy level (T 1 ). Matrix materials for fluorescent emitters:

[0161] Preferred matrix materials for fluorescent emitters are selected from the classes of oligoarylenes (e.g., 2,2',7,7'-tetraphenylspirobifluorene), in particular oligoarylenes containing fused aromatic groups, oligoarylene vinylenes, polypodal metal complexes, hole-conducting compounds, electron-conducting compounds, in particular ketones, phosphine oxides, and sulfoxides; atropisomers, boronic acid derivatives, or benzanthracenes. Particularly preferred matrix materials are selected from the classes of oligoarylenes containing naphthalene, anthracene, benzanthracene, and / or pyrene or atropisomers of these compounds, oligoarylene vinylenes, ketones, phosphine oxides, and sulfoxides. Particularly preferred matrix materials are selected from the classes of oligoarylenes containing anthracene, benzanthracene, benzphenanthrene and / or pyrene or atropisomers of these compounds.For the purposes of this invention, an oligoarylene shall be understood to be a compound in which at least three aryl or arylene groups are bonded to one another. Matrix materials for phosphorescent emitters:

[0162] Preferred matrix materials for phosphorescent emitters, besides the compounds of formula (I), are aromatic ketones, aromatic phosphine oxides or aromatic sulfoxides or sulfones, triarylamines, carbazole derivatives, e.g. CBP (N,N-biscarbazolylbiphenyl) or carbazole derivatives, indolocarbazole derivatives, indenocarbazole derivatives, azacarbazole derivatives, bipolar matrix materials, silanes, azaboroles or boron esters, triazine derivatives, zinc complexes, diazasilol or tetraazasilol derivatives, diazaphosphol derivatives, bridged carbazole derivatives, triphenylene derivatives, or lactams. Electron-transporting materials:

[0163] Other compounds that, besides the compounds of formula (I), are preferably used in electron-transporting layers of the OLEDs according to the invention, are, for example, the compounds disclosed in Y. Shirota et al., Chem. Rev. 2007, 107(4), 953-1010 or other materials such as are used in these layers according to the prior art.

[0164] Other compounds used in the electron transport layer besides those of formula (I) are all materials that can be used as electron transport materials in the electron transport layer according to the prior art. In particular, aluminum complexes, for example Alq 3, zirconium complexes, for example Zrq 4, lithium complexes, for example Liq, benzimidazole derivatives, triazine derivatives, pyrimidine derivatives, pyridine derivatives, pyrazine derivatives, quinoxaline derivatives, quinoline derivatives, oxadiazole derivatives, aromatic ketones, lactams, boranes, diazaphosphole derivatives, and phosphine oxide derivatives are suitable. Preferred electron-transporting compounds are shown in the following table: Hole transporting materials:

[0165]

[0166] All materials used in hole-transporting layers according to the prior art can be employed. Particularly suitable are indenofluorenamine derivatives, amine derivatives, hexaazatriphenylene derivatives, amine derivatives with fused aromatics, monobenzoindenofluorenamines, dibenzoindenofluorenamines, spirobifluorene amines, fluorene amines, spiro-dibenzopyran amines, dihydroacridine derivatives, spirodibenzofurans and spirodibenzothiophenes, phenanthrene diarylamines, spiro-tribenzotropolones, spirobifluorenes with meta-phenyldiamine groups, spiro-bisacridines, xanthene diarylamines, and 9,10-dihydroanthracene spiro compounds with diarylamine groups. Preferred hole-transporting compounds are shown in the following table: Wide-band-gap materials:

[0167] For the purposes of this application, wide-bandgap materials are understood to be materials such as those disclosed in US 7,294,849, characterized by a bandgap of at least 3.5 eV, where the term "bandgap" refers to the energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). Such systems are well known in the prior art and exhibit particularly advantageous performance characteristics in electroluminescence devices. n-dotted:

[0168] In the case of n-type ETLs, the ionization potential of the n-dope should be above the LUMO level of electron transport matrices. The LUMO level of n-ETLs is typically around 3.0 eV, and a higher HOMO energy (<3.0 eV) is required for an n-type dopant. Possible candidates for n-type dopants include alkali metals such as Li and Cs, or high-level HOMO molecules such as Ru(terpy)₂.

[0169] The introduction of a LiF layer between the electron transport layer and the contact metal has been shown to lower the operating voltage of OLEDs. This is explained by a type of n-doping effect caused by the released Li in Alq3. p-Dotanden:

[0170] It is further preferred to apply a p-doped hole transport material as a hole injection layer to the anode, with suitable p-doping materials being metal oxides, for example MoO₃ or WO₃, or (per)fluorinated electron-deficient aromatics. Other suitable p-doping materials are HAT-CN (hexacyanohexaazatriphenylene) or the compound NPD9 from Novaled. Such a layer simplifies hole injection into materials with a deep HOMO, i.e., a large HOMO magnitude.

[0171] Metals with low work function, metal alloys, or multilayer structures of different metals are preferred as cathodes for electronic devices. These include alkaline earth metals, alkali metals, main group metals, and lanthanides (e.g., Ca, Ba, Mg, Al, In, Mg, Yb, Sm, etc.). Alloys of an alkali or alkaline earth metal and silver are also suitable, for example, a magnesium-silver alloy. In multilayer structures, additional metals with relatively high work functions, such as Ag or Al, can be used, typically in combinations of these metals, such as Ca / Ag, Mg / Ag, or Ba / Ag. It may also be advantageous to insert a thin interlayer of a material with a high dielectric constant between a metallic cathode and the organic semiconductor.Suitable materials for this purpose include alkali metal or alkaline earth metal fluorides, as well as the corresponding oxides or carbonates (e.g., LiF, Li₂O, BaF₂, MgO, NaF, CsF, Cs₂CO₃, etc.). Lithium quinolinate (LiQ) can also be used. The thickness of this layer is preferably between 0.5 and 5 nm.

[0172] Materials with a high work function are preferred as anodes. Preferably, the anode has a work function greater than 4.5 eV vs. vacuum. Metals with a high redox potential, such as Ag, Pt, or Au, are suitable for this purpose. Alternatively, metal / metal oxide electrodes (e.g., Al / Ni / NiO₂, Al / PtO₂) may also be preferred. For some applications, at least one of the electrodes must be transparent or semi-transparent to allow either the irradiation of the organic material (organic solar cell) or the extraction of light (OLED, O-LASER). Conductive mixed metal oxides are preferred anode materials in this case. Indium tin oxide (ITO) or indium zinc oxide (IZO) are particularly preferred. Conductive doped organic materials, especially conductive doped polymers, are also preferred.Furthermore, the anode can also consist of several layers, for example an inner layer of ITO and an outer layer of a metal oxide, preferably tungsten oxide, molybdenum oxide or vanadium oxide.

[0173] In a preferred embodiment, the electronic device is characterized in that one or more layers are coated using a sublimation process. The materials are deposited in vacuum sublimation systems at an initial pressure of less than 10⁻⁵ mbar, preferably less than 10⁻⁶ mbar. However, it is also possible for the initial pressure to be even lower, for example less than 10⁻⁷ mbar.

[0174] A preferred electronic device is characterized in that one or more layers are coated using the OVPD (Organic Vapor Phase Deposition) process or by means of carrier gas sublimation. The materials are applied at a pressure between 10⁻⁵ mbar and 1 bar. A special case of this process is the OVJP (Organic Vapor Jet Printing) process, in which the materials are applied directly through a nozzle and thus structured (e.g., BMS Arnold et al., Appl. Phys. Lett. 2008, 92, 053301).

[0175] A further preferred electronic device is characterized in that one or more layers are produced from a solution, e.g., by spin coating, or by any printing process, e.g., screen printing, flexographic printing, nozzle printing, or offset printing, but particularly preferably LITI (light-induced thermal imaging, thermal transfer printing) or inkjet printing. Soluble compounds according to formula (I) are required for this purpose. High solubility can be achieved by suitable substitution of the compounds.

[0176] It is further preferred that, for the production of an electronic device according to the invention, one or more layers of solution and one or more layers are applied by a sublimation process.

[0177] After the layers are applied, the device is structured, contacted, and finally sealed, depending on the application, to exclude damaging effects from water and air.

[0178] According to the invention, the electronic devices containing one or more compounds according to formula (I) can be used in displays, as light sources in lighting applications, and as light sources in medical and / or cosmetic applications. Examples A) Synthesis examples

[0179] Unless otherwise specified, the following syntheses are carried out under a protective gas atmosphere in dried solvents. The starting materials can be obtained from ALDRICH (potassium fluoride (spray-dried), Tri- tert -butylphosphine, palladium(II) acetate). 3-Chloro-5,6-diphenyl-1,2,4-triazine can be prepared analogously to EP 577559. 2',7'-Di- tert-Butyl-spiro-9,9'-bifluorene-2,7-bisboronic glycol ester can be prepared according to WO 02 / 077060 and 2-chloro-4,6-diphenyl-1,3,5-triazine according to US 5,438138. Spiro-9,9'-bifluorene-2,7-bis(boronic glycol ester) can be prepared analogously to WO 02 / 077060. a) 6-chloroindeno[1,2-c]thiophen-4-one 1a

[0180]

[0181] 10 g (41.9 mmol) of 4-(4-chlorophenyl)thiophene-3-carboxylic acid is suspended in 73 ml of trifluoromethanesulfonic acid and heated at 90 °C for 2 hours. After cooling, the residue is poured onto ice and extracted with ethyl acetate. Following phase separation, the solvent is removed under vacuum and the residue is separated chromatographically (heptane / ethyl acetate, 1.1).

[0182] The yield is 2.9 g (13.4 mmol), corresponding to 32% of the theoretical yield. b) 6-chloro-4H-indeno[1,2-c]thiophene 1b

[0183]

[0184] A well-stirred, refluxing suspension of 55 g (250 mmol) of 6-chloroindeno[1,2-c]thiophen-4-one in a mixture of 1000 ml toluene and 2000 ml ethanol is treated with 49 ml (1000 mmol) of hydrazine hydrate and then with 3 g of freshly prepared Raney nickel. After 2 h under reflux, the mixture is allowed to cool, the solvent is removed under vacuum, the residue is dissolved in 1000 ml of warm chloroform, the solution is filtered through silica gel, the clear solution is concentrated to 100 ml, and 300 ml of ethanol is added. After standing for 12 h, the colorless crystals are filtered off by filtration and subsequently recrystallized twice from chloroform / ethanol.

[0185] Yield: 49 g (238 mmol), 96% of theory; Purity: 94% according to < 1H NMR.

[0186] The following connections can be obtained analogously: Reagent 1 product yield 2b 89% 3b 875 4b 90% 5b [6263-90-7 ] 89% c) 6-chloro-4,4-dimethyl-indeno[1,2-c]thiophene 1c

[0187]

[0188] 31 g (152 mmol) of 6-chloro-4H-indeno[1,2-c]thiophene are dissolved in 600 mL of dried DMSO in a heated flask. At room temperature, 43.9 g (457 mmol) of NaO t< Bu is added. The now blue suspension is heated to an internal temperature of 80 °C. At this temperature, 64.8 g (457 mmol) of iodomethane are added dropwise to the now violet solution, ensuring that the internal temperature does not exceed 90 °C (duration: approx. 30 min). The mixture is then heated for another 30 min at an internal temperature of 80–90 °C.

[0189] Yield: 30.5 g (132 mmol), 88% of theory; Purity: 96% by <1H NMR

[0190] The following connections can be obtained analogously: Reagent 1 product yield 2c 66% 3c 67% 4c 58% 5c 60% d) 6-chloro-1,3-diphenyl-indeno[1,2-c]thiophen-4-one 1d

[0191]

[0192] Molar sieve 4A is placed and baked out, then under protective gas with 30 g (136 mmol) of 6-chloroindeno[1,2-c]thiophen-4-one, 72 g (220 mmol) of calcium carbonate, 46 g (294 mmol) of bromobenzene, 2.2 g (7.3 mmol) of {[1,1'-biphenyl]-2-yl}di-tert-butyl)phosphine, and 0.83 g (3.6 mmol) of palladium(II) acetate in 325 ml of dry DMF and stirred overnight at 150 °C. The mixture is then filtered hot over Cellite, re-grown with ethyl acetate, concentrated, and recrystallized in toluene / heptane.

[0193] The yield is 30.4 g (82 mmol), corresponding to 60% of the theoretical yield. The following compounds can be obtained analogously: Reagent 1 Reagent 2 product yield 2d 67% 3d [1367747-08-7 ] 57% 4d [1511966-22-5 ] 61% 5d [864377-31-1] 60 % e) 4-bromo-1',3'-diphenyl-spiro[fluorene-9,4'-indeno[1,2-c]thiophene] 1e

[0194]

[0195] In a 1 L four-necked flask, 40 g (112.2 mmol) of 2,2'-dibromobiphenyl are placed in 350 mL of THF and cooled to -78 °C. 49 mL (123.5 mmol) are added via a dropping funnel. n -Butyllithium (2.5 M in n- Hexane) was added dropwise at this temperature and stirred for 1 hour. Then 38 g (112 mmol) of 1,3-diphenyl-8 were added. H -Indeno[1,2- c [Thiophen-8-one] dissolved in 300 mL THF was added via a dropping funnel and allowed to come to room temperature overnight. The THF was then evaporated by rotary extraction, followed by hydrolysis with 500 mL water / 200 mL ethyl acetate, and then dried. The solid was dissolved in 440 mL toluene and refluxed overnight with 2,1 (11.198 mmol) toluene-4-sulfonic acid monohydrate. Water and ethyl acetate were then added, the phases were separated, and the organic solvents were removed by rotary evaporator. The solid was then evaporated over aluminum oxide with n-Heptane / toluene (1:1) hot extracted and recrystallized into heptane / toluene.

[0196] The yield is 58.8 g (106 mmol), corresponding to 90% of the theory.

[0197] The following connections can be obtained analogously: Reagent 1 Reagent 2 product yield 2e [5706-22-9] 93% 3e [6072-53-3 ] 89% 4e [1924664-17-4] 90% 5e [1346266-91-8 ] 87% 6e [1407534-82-0 ] 84% 7e 91% 8e 92% f) 2-bromospiro[4a,8a-dihydroindeno[1,2-b]furan-4,9'-fluorene] 1f

[0198]

[0199] A solution of 46.2 g (150 mmol) of spiro[4a,8a-dihydroindeno[1,2-b]furan-4,9'-fluorene] in chloroform (900 mL) is added portionwise to N-bromosuccinimide (26.6 g, 150 mmol) at 0 °C under the protection of light and stirred at this temperature for 2 h. The reaction is stopped by the addition of sodium sulfite solution and stirred for a further 30 min 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 under vacuum. The residue is dissolved in toluene and filtered over silica gel. The crude product is then recrystallized from toluene / heptane.

[0200] Yield: 44 g (115 mmol), 77% of theory, colorless solid. g) (1',3'-diphenylspiro[fluorene-9,4'-indeno[1,2-c]thiophene]-4-yl)boronic acid 1g

[0201]

[0202] A solution of 144 g (270 mmol) of 4-bromo-1',3'-diphenyl-spiro[fluorene-9,4'-indeno[1,2-c]thiophene] in 1500 ml of diethyl ether, cooled to -78 °C, is treated dropwise with 110 ml (276 mmol) of n-butyllithium (2.5 M in hexane). The reaction mixture is stirred for 30 min at -78 °C. Allowed to reach room temperature, cooled again to -78 °C, and then rapidly treated with a mixture of 40 ml (351 mmol) of trimethyl borate in 50 ml of diethyl ether. After warming to -10 °C, the mixture is hydrolyzed with 135 ml of 2 N hydrochloric acid. The organic phase is separated, washed with water, dried over sodium sulfate, and concentrated to dryness. The residue is dissolved in 300 ml of n-heptane, the colorless solid is aspirated, washed with n-heptane and dried under vacuum.

[0203] Yield: 135 g (262 mmol), 97% of theory; Purity: 96% by HPLC.

[0204] The following connections can be obtained analogously: Reagent 1 product yield 2g [91155-62-7] 87% 3g [2291155-93-4] 84% 4g [899793-65-8] 71% 5g [885484-69-5 87% 6g 76% 7g 91% 8g [2291155-80-9 77% 9g 67% 10g [2291155-62-7] 65% 11g [2165343-88-2 52% 12g [2104697-12-10] 86% 13g [1346266-93-0] 66% 14g [911649-11-1] 62% 15g 87% 16g 67% 17g 59% h) 2-(1',3'-diphenylspiro[fluorene-9,4'-indeno[1,2-c]thiophene]-4-yl)-4,6-diphenyl-1,3,5-triazine 1h

[0205]

[0206] 57 g (110 mmol) of (1',3'-diphenylspiro[fluorene-9,4'-indeno[1,2-c]thiophene]-4-yl)boronic acid, 30 g (110.0 mmol) of 2-chloro-4,6-diphenyl-1,3,5-triazine, and 45 g (210.0 mmol) of tripotassium phosphate are suspended in 500 mL of toulol, 500 mL of dioxane, and 500 mL of water. To this suspension, 913 mg (3.0 mmol) of tri-o-tolylphosphine and then 112 mg (0.5 mmol) of palladium(II) acetate are added, and the reaction mixture is heated under reflux for 16 h. After cooling, the organic phase is separated, filtered over silica gel, washed three times with 200 mL of water, and then concentrated to dryness. The residue is made from toluene and dichloromethane / ISOPropanol was recrystallized and finally sublimed under high vacuum (p = 5 x 10⁻⁵ mbar, T = 377 °C). The yield was 63.6 g (90 mmol), corresponding to 82% of the theoretical yield.

[0207] The following connections can be obtained analogously: Reagent 1 Reagent 2 product yield 2h 40734-4-5 84% 3h [2142681-84-1] 88% 4h [2142681-84-1] 67% 5h [2251105-15-2 ] 71% 6h [864377-31-1] 75% 7h [864377-31-1] 79% 8h [2251105-15-2 ] 85% 9h [864377-31-1] 78% 10h [1373265-66-7] 80% 11h [3842-55-5] 81% 12h [3842-55-5] 82 % 13h [2915-16-4] 79% 14h [3842-55-5] 78% 15h [1205748-51-1] 87% 16h [3842-55-5] 72% 17h [40734-4-5] 61% 18h [3842-55-5] 79% 19h [3842-55-5] 75% 20h [2915-16-4] 67% 21h [864377-31-1] 82% 22h [864377-31-1] 76% 23h [2251105-15-2 ] 71% 24h [1205748-51-1] 73% 25h [1616231-59-41 70% 26h [1387596-01-1] 67% 27h [1403252-58-31 81% 28h [1342819-12-8] 76% 29h [1616231-59-4] 74% 30h [864377-31-1] 75% 31h [2165343-79-1] [1612243-82-9] 72% 32h [1518823-39-6] 70% 33h [1252825-65-6] 69% 34h [1252825-65-6] 81% 35h [1612243-82-9] 76% 36h [1612243-82-9] 66% 37h [1612243-82-9] 64% 36h [1252825-65-6] 67% 37h [1252825-65-6] 65% 38h 83% B) Device examples 1) General manufacturing process for the OLEDs and characterization of the OLEDs

[0208] Glass plates coated with structured ITO (indium tin oxide) of 50 nm thickness form the substrates onto which the OLEDs are applied.

[0209] The OLEDs generally have the following layer structure: substrate / optional interlayer (IL) / 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 can be found in the following tables. The structure of the manufactured OLEDs and the materials used for their fabrication are shown in Tables 2 and 3 below.

[0210] All materials are thermally vapor-deposited in a vacuum chamber. The emission layer consists of at least one matrix material (host material) and an emitting dopant, which is added to the matrix material(s) by co-evaporation in a specific volume fraction. A specification such as EG1:TER5 (97%:3%) means that material EG1 is present in the layer at a volume fraction of 97% and TER5 at a volume fraction of 3%. Similarly, the electron transport layer can also consist of a mixture of two materials.

[0211] The OLEDs are characterized according to standard procedures. This includes determining the electroluminescence spectra, the current efficiency (SE, measured in cd / A), and the external quantum efficiency (EQE, measured in %) as a function of luminance, calculated from current-voltage-luminance curves assuming a Lambertian emission characteristic, as well as the lifetime. The electroluminescence spectra are determined at a luminance of <1000 cd / m², and the CIE 1931 x and y color coordinates are calculated from them. The value U1000 in Table 4 denotes the voltage required for a luminance of <1000 cd / m². SE1000 and EQE1000 denote the current efficiency and external quantum efficiency, respectively, achieved at <1000 cd / m².

[0212] The lifetime LD is defined as the time after which the luminance, when operating at a constant current density j0, decreases from the initial luminance to a certain fraction L1. An entry L1=95% in Table 4 means that the lifetime specified in column LD corresponds to the time after which the luminance decreases to 95% of its initial value. 2) Use and advantage of the compounds of formula (I) according to the invention in OLEDs

[0213] Typically, the emission layer of OLEDs uses a mixture of two host materials to achieve optimal charge balance and thus very good OLED performance. For simplified OLED manufacturing, reducing the number of materials used is desirable. Therefore, using only one host material in the emission layer is advantageous. 2a) Use of compounds according to the invention in the emission layer of phosphorescent red OLEDs

[0214] By using the compounds EG1 to EG2 according to the invention in examples E1 and E2 as well as E5 and E6 as matrix material in the emission layer of phosphorescent red OLEDs, it can be shown that the use as a single material (E1 and E5) and especially in mixture with a second host material IC2 (E2 and E6) provides improved performance data of the OLEDs compared to the prior art, especially with regard to lifetime and efficiency. 2b) Use of compounds according to the invention in the emission layer of phosphorescent green OLEDs

[0215] By using the compounds EG3 to EG6 according to the invention with higher triplet energy in examples E9 to E12 as matrix material in the emission layer of phosphorescent green OLEDs, it can be shown that the use in mixture with a second host material IC2 provides a good lifetime.

[0216] Table 4 summarizes the performance data results for the OLEDs from examples E1 to E12. 2c) Use of compounds according to the invention as electron transport material in the electron transport layer of OLEDs

[0217] When using the compounds EG3 to EG6 according to the invention as electron transport material, significantly lower voltage and better efficiency and lifetime are obtained (examples E15 to E18) than with the substances SdT1 and SdT2 according to the prior art (examples E13 to E14).

[0218] Table 5 summarizes the performance data results for the OLEDs from examples E13 to E18. Table 2: Structure of OLEDs Example IL HIL Thickness HTL Thickness EBL Thickness EML thickness HBL thickness ETL Thickness UR Thickness E1 HATCN 5nm SpMA1 125nm SpMA3 10nm EG1:TER5 (97%:3%) 35nm ST2 10nm ST2:LiQ (50%:50%) 30nm LiQ 1nm E2 HATCN 5nm SpMA1 125nm SpMA3 10nm EG1:IC2:TER5 (44%:44%:12%) 30nm ST2 10nm ST2:LiQ (50%:50%) 30nm LiQ 1nm E3 HATCN 5nm SpMA1 125nm SpMA3 10nm SdT1:TER5 (97%:3%) 35nm ST2 10nm ST2:LiQ (50%:50%) 30nm LiQ 1nm E4 HATCN 5nm SpMA1 125nm SpMA3 10nm SdT1:IC2:TER5 (44%:44%:12%) 30nm ST2 10nm ST2:LiQ (50%:50%) 30nm LiQ 1nm E5 HATCN 5nm SpMA1 125nm SpMA3 10nm EG2:TER5 (97%:3%) 35nm ST2 10nm ST2:LiQ (50%:50%) 30nm LiQ 1nm E6 HATCN 5nm SpMA1 125nm SpMA3 10nm EG2:IC2:TER5 (44%:44%:12%) 30nm ST2 10nm ST2:LiQ (50%:50%) 30nm LiQ 1nm E7 HATCN 5nm SpMA1 125nm SpMA3 10nm SdT2:TER5 (97%:3%) 35nm ST2 10nm ST2:LiQ (50%:50%) 30nm LiQ 1nm E8 HATCN 5nm SpMA1 125nm SpMA3 10nm SdT2:IC2:TER5 (44%:44%:12%) 30nm ST2 10nm ST2:LiQ (50%:50%) 30nm LiQ 1nm E9 HATCN 5nm SpMA1 125nm SpMA3 10nm EG3:IC2:TEG1 (44%:44%:12%) 30nm ST2 10nm ST2:LiQ (50%:50%) 30nm LiQ 1nm E10 HATCN 5nm SpMA1 125nm SpMA3 10nm EG4:IC2: TEG1 (44%:44%:12%) 30nm ST2 10nm ST2:LiQ (50%:50%) 30nm LiQ 1nm E11 HATCN 5nm SpMA1 125nm SpMA3 10nm EG5:IC2: TEG1 (44%:44%:12%) 30nm ST2 10nm ST2:LiQ (50%:50%) 30nm LiQ 1nm E12 HATCN 5nm SpMA1 125nm SpMA3 10nm EG6:IC2:TEG1 (44%:44%:12%) 30nm ST2 10nm ST2:LiQ (50%:50%) 30nm LiQ 1nm E13 SpA1 140nm HATCN 5nm SpMA1 20nm M2:SEB (95%:5%) 20nm - SdT1:LiQ (50%:50%) 30nm - E14 SpA1 70nm HATCN 5nm SpMA1 90nm IC1:TEG1 (90%:10%) 30nm IC1 10nm SdT2:LiQ (50%:50%) 30nm - E15 SpA1 140nm HATCN 5nm SpMA1 20nm M2:SEB (95%:5%) 20nm - EG4:LiQ (50%:50%) 30nm - E16 SpA1 70nm HATCN 5nm SpMA1 90nm IC1:TEG1 (90%:10%) 30nm IC1 10nm EG4:LiQ (50%:50%) 30nm - E17 SpA1 140nm HATCN 5nm SpMA1 20nm M2:SEB (95%:5%) 20nm - EG5:LiQ (50%:50%) 30nm - E18 SpA1 70nm HATCN 5nm SpMA1 90nm IC1:TEG1 (90%:10%) 30nm - EG6:LiQ (50%:50%) 40nm - Table 4: OLED Data Bsp. U1000 (V) SE10 00 (cd / A) EQE 1000 (%) CIE x / y bei 1000 cd / m 2< j 0 (mA / cm²< ) L1 (%) LD(h) E1 4,3 23 15 0.67 / 0.33 20 95 500 E2 3.3 23 20 0.66 / 0.34 20 95 1110 E3 3.9 23 14 0.66 / 0.33 20 95 410 E4 3.4 24 15 0.67 / 0.34 20 95 840 E5 3.9 23 20 0.66 / 0.33 20 95 830 E6 3.4 23 21 0.66 / 0.34 20 95 1000 E7 3.8 23 15 0.67 / 0.33 20 95 540 E8 3.8 24 18 0.67 / 0.33 20 95 760 E9 3.5 70 17,5 0.32 / 0.64 20 80 700 E10 3.2 67 19.1 0.33 / 0.63 20 80 820 E11 3.1 69 18.8 0.32 / 0.64 20 80 790 E12 3.2 74 18.5 0.32 / 0.63 20 80 766 Table 5: OLED Data Bsp U1000 (V) CE1000 (cd / A) LE1000 (Im / W) EQE 1000 CIE x / y at 1000 cd / m² L 0 ; j 0 L 1 % LT (h) E13 6 5 7.0% 0.13 / 0.14 6000 cd / m² 80 30 E14 5.0 62 53 13% 0.31 / 0.64 20 mA / cm² 80 50 E15 4,1 8 5 7.0% 0.13 / 0.14 6000 cd / m² 80 45 E16 3.6 62 53 17.4% 0.31 / 0.64 20 mA / cm² 80 142 E17 3.5 8 6 7.3% 0.14 / 0.13 6000 cd / m² 80 47 E18 3.2 62 51 16.1% 0.34 / 0.62 20 mA / cm² 80 124

Claims

1. Compound according to formula (I) wherein Y is on each occurrence, identically or differently, selected from O, S, NAr0 and CAr1, wherein at least one Y is selected from O, S and NAr0; Z is on each occurrence, identically or differently, selected from N and CR1; Ar0 is on each occurrence, identically or differently, selected from aromatic ring systems having 6 to 40 aromatic ring atoms which are substituted by radicals R2 and heteroaromatic ring systems having 5 to 40 aromatic ring atoms which are substituted by radicals R2; Ar1 is on each occurrence, identically or differently, selected from H, D, F, Cl, Br, I, C(=O)R2, CN, Si(R2)3, P(=O)(R2)2, OR2, S(=O)R2, S(=O)2R2, straight-chain alkyl or alkoxy groups having 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups having 3 to 20 C atoms, alkenyl or alkynyl groups having 2 to 20 C atoms, aromatic ring systems having 6 to 40 aromatic ring atoms, and heteroaromatic ring systems having 5 to 40 aromatic ring atoms; wherein said alkyl, alkoxy, alkenyl and alkynyl groups and said aromatic ring systems and heteroaromatic ring systems are each substituted by radicals R2; and wherein one or more CH2 groups in said alkyl, alkoxy, alkenyl and alkynyl groups may be substituted by -R2C=CR2-, -C≡C-, Si(R2)2, C=O, C=NR2, -C(=O)O-, -C(=O)NR2-, NR2, P(=O)(R2), -O-, -S-, SO or SO2; wherein it is ruled out that two groups Ar1 are linked together to form a mono- or polycyclic, aliphatic or aromatic ring system; R0 is on each occurrence, identically or differently, selected from H, D, F, Cl, Br, I, C(=O)R1, CN, Si(R1)3, N(R1)2, P(=O)(R1)2, OR1, S(=O)R1, S(=O)2R1, straight-chain alkyl, alkoxy or thioalkyl groups having 1 to 20 C atoms, branched or cyclic alkyl, alkoxy or thioalkyl groups having 3 to 20 C atoms, alkenyl or alkynyl groups having 2 to 20 C atoms, aromatic ring systems having 6 to 40 aromatic ring atoms, heteroaromatic ring systems having 5 to 40 aromatic ring atoms, aryloxy or heteroaryloxy groups having 5 to 40 aromatic ring atoms, and aralkyl groups having 5 to 40 aromatic ring atoms; wherein the two radicals R0 may be linked together and may form an aliphatic or heteroaliphatic ring, so that a spiro compound is formed in position 8 of the fluorene derivative, in particular a spirobifluorene derivative; wherein said alkyl, alkoxy, thioalkyl, alkenyl, alkynyl, aryloxy, heteroaryloxy and aralkyl groups and said aromatic ring systems and heteroaromatic ring systems are each substituted with radicals R1; and wherein one or more CH2 groups in said alkyl, alkoxy, thioalkyl, alkenyl, alkynyl, aryloxy, heteroaryloxy and aralkyl groups may be substituted by -R1C=CR1-, -C≡C-, Si(R1)2, C=O, C=NR1, -C(=O)O-, -C(=O)NR1-, NR1, P(=O)(R1), -O-, -S-, SO or SO2; R1 is on each occurrence, identically or differently, selected from H, D, F, Cl, Br, I, C(=O)R5, CN, Si(R5)3, P(=O)(R5)2, OR5, S(=O)R5, S(=O)2R5, straight-chain alkyl or alkoxy groups having 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups having 3 to 20 C atoms, alkenyl or alkynyl groups having 2 to 20 C atoms, aromatic ring systems having 6 to 40 aromatic ring atoms, and heteroaromatic ring systems having 5 to 40 aromatic ring atoms; wherein two or more radicals R1 may be linked together and may form an aliphatic or heteroaliphatic ring; wherein said alkyl, alkoxy, alkenyl and alkynyl groups and said aromatic ring systems and heteroaromatic ring systems are each substituted by radicals R5; and wherein one or more CH2 groups in said alkyl, alkoxy, alkenyl and alkynyl groups may be substituted by -R5C=CR5-, -C≡C-, Si(R5)2, C=O, C=NR5, -C(=O)O-, - C(=O)NR5-, NR5, P(=O)(R5), -O-, -S-, SO or SO2; R2 is on each occurrence, identically or differently, selected from H, D, F, Cl, Br, I, C(=O)R5, CN, Si(R5)3, P(=O)(R5)2, OR5, S(=O)R5, S(=O)2R5, straight-chain alkyl or alkoxy groups having 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups having 3 to 20 C atoms, alkenyl or alkynyl groups having 2 to 20 C atoms, aromatic ring systems having 6 to 40 aromatic ring atoms, and heteroaromatic ring systems having 5 to 40 aromatic ring atoms; wherein two or more radicals R2 may be linked together and may form a ring; wherein said alkyl, alkoxy, alkenyl and alkynyl groups and said aromatic ring systems and heteroaromatic ring systems each may be substituted by radicals R5; and wherein one or more CH2 groups in said alkyl, alkoxy, alkenyl and alkynyl groups may be substituted by -R5C=CR5-, -C≡C-, Si(R5)2, C=O, C=NR5, -C(=O)O-, -C(=O)NR5-, NR5, P(=O)(R5), -O-, -S-, SO or SO2; R5 is on each occurrence, identically or differently, selected from H, D, F, Cl, Br, I, C(=O)R6, CN, Si(R6)3, P(=O)(R6)2, OR6, S(=O)R6, S(=O)2R6, straight-chain alkyl or alkoxy groups having 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups having 3 to 20 C atoms, alkenyl or alkynyl groups having 2 to 20 C atoms, aromatic ring systems having 6 to 40 aromatic ring atoms, and heteroaromatic ring systems having 5 to 40 aromatic ring atoms; wherein two or more radicals R5 may be linked together and may form a ring; wherein said alkyl, alkoxy, alkenyl and alkynyl groups and said aromatic ring systems and heteroaromatic ring systems each may be substituted by radicals R6; and wherein one or more CH2 groups in said alkyl, alkoxy, alkenyl and alkynyl groups may be substituted by -R6C=CR6-, -C=C-, Si(R6)2, C=O, C=NR6, -C(=O)O-, -C(=O)NR6-, NR6, P(=O)(R6), -O-, -S-, SO or SO2; R6 is on each occurrence, identically or differently, selected from H, D, F, CI, Br, I, CN, alkyl or alkoxy groups having 1 to 20 C atoms, alkenyl or alkynyl groups having 2 to 20 C atoms, aromatic ring systems having 6 to 40 aromatic ring atoms and heteroaromatic ring systems having 5 to 40 aromatic ring atoms; wherein two or more radicals R6 may be linked together and form a ring; and wherein said alkyl, alkoxy, alkenyl and alkynyl groups, aromatic ring systems and heteroaromatic ring systems may be substituted by one or more radicals selected from F and CN; and in formula (I), at least one radical R1, a group Ar0 or a group Ar1 is substituted by a group A which corresponds to a formula (A): wherein * denotes the bond to the structure of formula (I); ArL is on each occurrence, identically or differently, selected from aromatic ring systems having 6 to 40 aromatic ring atoms which are substituted by radicals R2 and heteroaromatic ring systems having 5 to 40 aromatic ring atoms which are substituted by radicals R2; ET is on each occurence, identically or differently, an electron-transporting group selected from electron-poor heteroaromatic groups to which one or more Ar2 groups are bonded; Ar2 is on each occurrence, identically or differently, selected from H, D, F, Cl, Br, I, C(=O)R3, CN, Si(R3)3, P(=O)(R3)2, OR3, S(=O)R3, S(=O)2R3, straight-chain alkyl or alkoxy groups having 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups having 3 to 20 C atoms, alkenyl or alkynyl groups having 2 to 20 C atoms, aromatic ring systems having 6 to 40 aromatic ring atoms, and heteroaromatic ring systems having 5 to 40 aromatic ring atoms; wherein said alkyl, alkoxy, alkenyl and alkynyl groups and said aromatic ring systems and heteroaromatic ring systems are each substituted by radicals R3; wherein one or more CH2 groups in said alkyl, alkoxy, alkenyl and alkynyl groups may be substituted by -R3C=CR3-, -C≡C-, Si(R3)2, C=O, C=NR3, -C(=O)O-, -C(=O)NR3-, NR3, P(=O)(R3), -O-, -S-, SO or SO2; and wherein two or more adjacent groups Ar2 can form a mono- or polycyclic, aliphatic or aromatic ring system; R3 is on each occurrence, identically or differently, selected from H, D, F, Cl, Br, I, C(=O)R5, CN, Si(R5)3, N(R5)2, P(=O)(R5)2, OR5, S(=O)R5, S(=O)2R5, straight-chain alkyl or alkoxy groups having 1 to 20 C atoms, branched or cyclic alkyl or alkoxy groups having3 to 20 C atoms, alkenyl or alkynyl groups having 2 to 20 C atoms, aromatic ring systems having 6 to 40 aromatic ring atoms, and heteroaromatic ring systems having 5 to 40 aromatic ring atoms; wherein two or more radicals R3 may be linked together and may form a ring; wherein said alkyl, alkoxy, alkenyl and alkynyl groups and said aromatic ring systems and heteroaromatic ring systems are each substituted by radicals R5; and wherein one or more CH2 groups in said alkyl, alkoxy, alkenyl and alkynyl groups may be substituted by -R5C=CR5-, -C≡C-, Si(R5)2, C=O, C=NR5, -C(=O)O-, -C(=O)NR5-, NR5, P(=O)(R5), -O-, -S-, SO or SO2; and n is equal to 0 or 1.

2. Compound according to claim 1, characterised in that exactly one Y is selected from O, S and NAr0 and two Y are equal to CAr1.

3. Compound according to claim 1 or 2, characterised in that the groups Z are equal to CR1.

4. Compound according to one or more of claims 1 to 3, characterised in that the group ET is on each occurrence, identically or differently, selected from heteroaryl groups having 5 to 40 aromatic ring atoms substituted by groups Ar2.

5. Compound according to one or more of claims 1 to 4, characterised in that the group ET is on each occurrence, identically or differently, selected from the groups of formulae (ET-1) to (ET-11c): wherein Q' is on each occurrence, identically or differently, selected from CAr2 or N; Q" is on each occurrence, identically or differently, selected from NR2, O or S; the dashed line in each case marks the position of attachment to the remainder of formula (I) and R2 and Ar2 are defined as in claim 1; and wherein at least one Q' is equal to N.

6. Compound according to one or more of claims 1 to 5, characterised in that the group ET, is on each occurrence, identically or differently, selected from the groups of formulae (ET-12) to (ET-35) wherein the dashed lines represent the bonds to the remainder of formula (I) and Ar2 is defined as in claim 1.

7. Compound according to one or more of claims 1 to 6, characterised in that it corresponds to the following formula (I-A) wherein the variables are as defined in one or more of claims 1 to 11 and there is at least one group A per formula; and R4 is on each occurrence, identically or differently, selected from H, D, F, Cl, Br, I, C(=O)R1, CN, Si(R1)3, N(R1)2, P(=O)(R1)2, OR1, S(=O)R1, S(=O)2R1, straight-chain alkyl, alkoxy or thioalkyl groups having 1 to 20 C atoms, branched or cyclic alkyl, alkoxy or thioalkyl groups having 3 to 20 C atoms, alkenyl or alkynyl groups having 2 to 20 C atoms, aromatic ring systems having 6 to 40 aromatic ring atoms, heteroaromatic ring systems having 5 to 40 aromatic ring atoms, aryloxy or heteroaryloxy groups having 5 to 40 aromatic ring atoms, and aralkyl groups having 5 to 40 aromatic ring atoms; wherein it is ruled out that the two radicals R4 are linked together and form an aliphatic or heteroaliphatic ring; wherein said alkyl, alkoxy, thioalkyl, alkenyl, alkynyl, aryloxy, heteroaryloxy and aralkyl groups and said aromatic ring systems and heteroaromatic ring systems are each substituted by radicals R1; and wherein one or more CH2 groups in said alkyl, alkoxy, thioalkyl, alkenyl, alkynyl, aryloxy, heteroaryloxy and aralkyl groups may be substituted by -R1C=CR1-, -C=C-, Si(R1)2, C=O, C=NR1, -C(=O)O-, -C(=O)NR1-, NR1, P(=O)(R1), -O-, -S-, SO or SO2.

8. Compound according to one or more of claims 1 to 7, characterised in that it corresponds to one of the following formulae (II-A), (III-A) and (IV-A) wherein the variables are defined as in one or more of claims 1 to 7 and there is at least one group A per formula; and R4 is on each occurrence, identically or differently, selected from F, CN, Si(R1)3, straight-chain alkyl groups having 1 to 20 C atoms, branched or cyclic alkyl groups having 3 to 20 C atoms, aromatic ring systems having 6 to 40 aromatic ring atoms, and heteroaromatic ring systems having 5 to 40 aromatic ring atoms; wherein the said alkyl groups and the said aromatic ring systems and heteroaromatic ring systems are each substituted by radicals R1 and wherein it is ruled out that the two radicals R4 are linked together and form an aliphatic or heteroaliphatic ring.

9. Compound according to one or more of claims 1 to 6, characterised in that it corresponds to the following formula (I-B): wherein W is on each occurrence, identically or differently, selected from N and CR1; U is selected from O and S; k is 0 or 1, wherein in the case k=0 the heteroatom U in question is omitted and U is instead a single bond connecting the corresponding two aromatic six-membered rings; and at least one group A is present in formula (I-B), wherein the variables Z, Y and R1 and the at least one group A are as defined in any one of claims 1 to 6.

10. Compound according to claim 9, characterised in that it corresponds to one of the following formulae (II-B) to (IV-B) and (II-C) to (IV-C): formula (II-B)formula (III-B) formula (IV-B)formula (II-C) formula (III-C)formula (IV-C) wherein the variables are as defined in one or more of claims 9 and 1 to 6 and the free positions on the benzene rings are each substituted by radicals R1, and wherein at least one group A is present per formula.

11. Oligomer, polymer or dendrimer containing one or more compounds according to one or more of claims 1 to 10, wherein the bond(s) to the polymer, oligomer or dendrimer may be located at any positions substituted with R0, R1, R2 or R3 in formula (I).

12. Formulation containing at least one compound according to one or more of claims 1 to 10 or at least one polymer, oligomer or dendrimer according to claim 11, and at least one solvent.

13. Composition containing at least one compound according to one or more of claims 1 to 10 or at least one polymer, oligomer or dendrimer according to claim 11, and at least one further compound selected from hole injection materials, hole transport materials, hole blocking materials, wide-band-gap materials, fluorescent emitters, phosphorescent emitters, delayed fluorescent materials, host materials, matrix materials, electron blocking materials, electron transport materials and electron injection materials, n-dotands and p-dotands.

14. Electronic device containing at least one compound according to one or more of claims 1 to 10, at least one polymer, oligomer or dendrimer according to claim 11, or a composition according to claim 13.

15. Electronic device according to claim 14, characterised in that it is an organic electroluminescent device and contains an anode, cathode and at least one emitting layer, and in that the compound is contained in an electron transporting layer or in an emitting layer of the device.

16. Electronic device according to claim 15, characterised in that the compound as electron transporting material is in the electron transport layer and one or more further electron transporting compounds are additionally contained in the electron transport layer or in the electron injection layer, wherein the further electron transporting compounds are preferably a hydroxyquinolinate, very preferably a Liq derivative and very particularly preferably Liq.

17. An electronic device according to claim 15, characterised in that the compound is contained as an electron transporting material in the emitting layer together with a hole transporting material.

18. Use of a connection according to one or more of claims 1 to 10 in an electronic device.