MATERIALS FOR ELECTRONIC DEVICES

Description

[0001] The present application relates to triarylamine compounds according to a formula (I) defined below. These compounds are suitable for use in electronic devices. Furthermore, the present application relates to methods for producing the said compounds, as well as electronic devices containing the said compounds.

[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] For electronic devices, especially OLEDs, there is great interest in improving performance data, particularly lifespan, efficiency, and operating voltage. A completely satisfactory solution has not yet been found in these areas.

[0004] Emission layers and hole-transporting layers have a significant influence on the performance of electronic devices. New compounds are still being sought for use in these layers, particularly hole-transporting compounds and compounds that can serve as matrix materials, especially for phosphorescent emitters, within an emitting layer.

[0005] Various triarylamine compounds are known in the prior art as hole transport materials for electronic devices.

[0006] The use of certain triarylamine compounds as matrix materials in emitting layers is also known.

[0007] EP 2 348 017 A1 discloses triarylamine compounds of general formula (1) and, among other things, a compound of formula [B-36]

[0008] However, there is still a need for alternative compounds suitable for use in electronic devices.

[0009] There is also room for improvement regarding performance data when used in electronic devices, particularly concerning operating voltage, lifetime, and efficiency. Furthermore, improvements are needed regarding the processability of the materials, their glass transition temperature, solubility, stability in solution, and refractive index.

[0010] It has now been found that certain triarylamine compounds are excellently suited for use in electronic devices, especially for use in OLEDs, and in particular for use as hole transport materials and as matrix materials for phosphorescent emitters.

[0011] The subject of the present application is therefore combinations according to a formula (I) where the subunit Formula (I) is chosen from the following structures: Formel (I-A-45) Formel (I-A-46) Formel (I-A-47) Formel (I-A-49) Formel (I-A-50) Formel (I-A-51) Formel (I-A-53) Formel (I-A-54) Formel (I-A-55) Formel (I-A-57) Formel (I-A-58) Formel (I-A-59) Formel (I-A-60) Formel (I-A-62) Formel (I-A-63) Formel (I-A-64) Formel (I-A-66) Formel (I-A-67) Formel (I-A-68) Formel (I-A-69) Formel (I-A-71) Formel (I-A-72) Formel (I-A-73) Formel (I-A-75) Formel (I-A-76) Formel (I-A-77) Formel (I-A-78) Formel (I-A-80) Formel (I-A-81) Formel (I-A-82) Formel (I-A-84) Formel (I-A-85) Formel (I-A-86) Formel (I-A-87) Formel (I-A-88) Formel (I-A-90) Formel (I-A-91) Formel (I-A-93) Formel (I-A-94) Formel (I-A-95) Formel (I-A-96) Formel (I-A-109) Formel (I-A-111) Formel (I-A-112) Formel (I-A-113) Formel (I-A-114) Formel (I-A-115) Formel (I-A-116) Formel (I-A-118) Formel (I-A-119) Formel (I-A-121) Formel (I-A-122) where the dashed line represents the bond to the N atom in formula (I), and where the following applies to the variables that occur: Ar 2< corresponds to a formula (A) or (B) Z 2< is the same as or different from CR 3< or N at each occurrence, where Z 2< is equal to C if a group L 1< is bonded to it; L 1< is a single bond, or an aromatic ring system with 6 to 30 aromatic ring atoms, which may be substituted with one or more R 3< residues, or a heteroaromatic ring system with 5 to 30 aromatic ring atoms, which may be substituted with one or more R 3< residues; Ar 3< corresponds to formula (A), formula (B), or is an aromatic ring system with 6 to 30 aromatic ring atoms, which may be substituted with one or more R 4< residues, or a heteroaromatic ring system with 5 to 30 aromatic ring atoms, which may be substituted with one or more R 4< residues;R 3< , R 4< are chosen the same or differently from H, D, F, C(=O)R 5< , CN, Si(R 5< ) 3 , N(R 5< ) 2 , 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 3< or R 4< 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 can each be substituted with one or more R 5< residues;and where 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; R 5< is chosen in each instance as the same or different from H, D, F, C(=O)R 6< , CN, Si(R 6< ) 3 , N(R 6< ) 2 , 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 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 R 5< residues may be linked together and form a ring;wherein the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups and the aforementioned aromatic and heteroaromatic ring systems may each be substituted with one or more R 6< residues; and wherein one or more CH 2 groups in the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups may 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, 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 form a ring;and wherein the aforementioned alkyl, alkoxy, alkenyl and alkynyl groups, aromatic ring systems and heteroaromatic ring systems may be substituted with F or CN.

[0012] An aryl group within the meaning of this invention comprises 6 to 40 aromatic ring atoms, none of which is a heteroatom. An aryl group within the meaning of this invention is understood to be either a simple aromatic cycle, i.e., benzene, or a condensed aromatic polycycle, for example, naphthalene, phenanthrene, or anthracene. A condensed aromatic polycycle within the meaning of this application consists of two or more simple aromatic cycles condensed together. Condensation between cycles is understood to mean that the cycles share at least one edge.

[0013] A heteroaryl group according to this invention comprises 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. A heteroaryl group according to this invention is understood to be either a simple heteroaromatic cycle, for example, pyridine, pyrimidine, or thiophene, or a condensed heteroaromatic polycycle, for example, quinoline or carbazole. A condensed heteroaromatic polycycle according to the present application consists of two or more simple heteroaromatic cycles condensed together. Condensation between cycles means that the cycles share at least one edge.

[0014] An aryl or heteroaryl group, which may be substituted with any of the aforementioned residues and which may be linked via any position on the aromatic or heteroaromatic compound, is understood to include, in particular, 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, and benzimidazole. Naphthimidazole, phenanthrimidazole, pyridimidazole, pyrazinimidazole, quinoxalinimidazole, oxazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, 1,2-thiazole, 1,3-thiazole, benzothiazole, pyridazine, benzopyridazine, pyrimidine,Benzpyrimidin, Chinoxalin, Pyrazin, Phenazin, Naphthyridin, Azacarbazol, Benzocarbolin, Phenanthrolin, 1,2,3-Triazol, 1,2,4-Triazol, Benzotriazol, 1,2,3-Oxadiazol, 1,2,4-Oxadiazol, 1,2,5-Oxadiazol, 1,3,4-Oxadiazol, 1,2,3-Thiadiazol, 1,2,4-Thiadiazol, 1,2,5-Thiadiazol, 1,3,4-Thiadiazol, 1,3,5-Triazin, 1,2,4-Triazin, 1,2,3-Triazin, Tetrazol, 1,2,4,5-Tetrazin, 1,2,3,4-Tetrazin, 1,2,3,5-Tetrazin, Purin, Pteridin, Indolizin und Benzothiadiazol.,

[0015] An aromatic ring system according to this invention contains 6 to 40 carbon atoms in the ring system and does not include any heteroatoms as aromatic ring atoms. An aromatic ring system according to this invention therefore does not contain any heteroaryl groups. An aromatic ring system according to this invention is understood to be a system that does not necessarily contain only aryl groups, but in which several aryl groups may also be connected by a single bond or by a non-aromatic unit, such as one or more optionally substituted carbon, silicon, nitrogen, oxygen, or sulfur atoms. The non-aromatic unit preferably comprises less than 10% of the non-hydrogen atoms, based on the total number of non-hydrogen atoms in the system.For example, systems such as 9,9'-spirobifluorene, 9,9'-diarylfluorene, triarylamine, diaryl ethers, and stilbene are to be understood as aromatic ring systems within the meaning of this invention, as are systems in which two or more aryl groups are connected, for example, by a linear or cyclic alkyl, alkenyl, or alkynyl group, or by a silyl group. Furthermore, systems in which two or more aryl groups are linked to one another via single bonds are also to be understood as aromatic ring systems within the meaning of this invention, such as systems like biphenyl and terphenyl.

[0016] A heteroaromatic ring system according to this invention contains 5 to 40 aromatic ring atoms, at least one of which is a heteroatom. The heteroatoms of the heteroaromatic ring system are preferably selected from N, O, and / or S. A heteroaromatic ring system corresponds to the above definition of an aromatic ring system, but has at least one heteroatom as one of the aromatic ring atoms. It differs from an aromatic ring system as defined in the present application, which, according to that definition, cannot contain a heteroatom as an aromatic ring atom.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] Preferred embodiments of formula (A) are formulas (A-1) to (A-10) Formel (A-1) Formel (A-2) Formel (A-3) Formel (A-4) Formel (A-5) Formel (A-6) Formel (A-7) Formel (A-8) Formel (A-9) Formel (A-10) wherein the variables occurring are defined as above, and wherein the carbazole units at the free positions of their two benzene rings each have one or more R groups 3 may be substituted.

[0022] Preferred embodiments of formula (B) are formulas (B-1) to (B-7) Formel (B-1) Formel (B-2) Formel (B-3) Formel (B-4) Formel (B-5) Formel (B-6) Formel (B-7) wherein the variables occurring are defined as above, and wherein the carbazole units at the free positions of their two benzene rings each have one or more R groups 3 may be substituted.

[0023] Ar 2< preferably corresponds to the above-mentioned formula (A), particularly preferably to one of the formulas (A-1) to (A-3).

[0024] Preferred embodiments of the groups Ar 2< are shown in the following table: Ar 2< -1 Ar 2< -2 Ar 2< -3 Ar 2< -4 Ar 2< -5 Ar 2< -6 Ar 2< -7 Ar 2< -8 Ar 2< -9 Ar 2< -10 Ar 2< -11 Ar 2< -12 Ar 2< -13 Ar 2< -14 Ar 2< -15 Ar 2< -16 Ar 2< -17 Ar 2< -18 Ar 2< -19 Ar 2< -20 Ar 2< -21 Ar 2< -22 Ar 2< -23 Ar 2< -24 Ar 2< -25 Ar 2< -26 Ar 2< -27 Ar 2< -28 Ar 2< -29 Ar 2< -30 Ar 2< -31 Ar 2< -32 Ar 2< -33 Ar 2< -34 Ar 2< -35 Ar 2< -36 Ar 2< -37 Ar 2< -38 Ar 2< -39 Ar 2< -40 Ar 2< -41 Ar 2< -42 Ar 2< -43 Ar 2< -44 Ar 2< -45 Ar 2< -46 Ar 2< -47 Ar 2< -48 Ar 2< -49 Ar 2< -50 Ar 2< -51 Ar 2< -52 Ar 2< -53 Ar 2< -54 Ar 2< -55 Ar 2< -56 Ar 2< -57 Ar 2< -58 Ar 2< -59 Ar 2< -60 Ar 2< -61 Ar 2< -62 Ar 2< -63 Ar 2< -64 Ar 2< -65 Ar 2< -66 Ar 2< -67 Ar 2< -68 Ar 2< -69 Ar 2< -70 Ar 2< -71 Ar 2< -72 Ar 2< -73 Ar 2< -74 Ar 2< -75 Ar 2< -76

[0025] Z 2< is preferably equal to CR 3< in every occurrence, where Z 2< is equal to C if a group L 1< is bound to it.

[0026] L1< is preferably selected from aromatic ring systems with 6 to 30 aromatic ring atoms. L1< is particularly preferably selected from single bond, benzene, naphthalene, para-biphenyl, meta-biphenyl, ortho-biphenyl, terphenyl, dibenzofuran, carbazole, dibenzothiophene, pyridine, pyrimidine, pyrazine, pyridazine, triazine and fluorene, and most preferably from single bond and phenyl, wherein the aforementioned groups may each be substituted with one or more R3< groups.

[0027] Preferred groups L 1< are shown in the following table: (L 1< -1) (L 1< -2) (L 1< -3) (L 1< -4) (L 1< -5) (L 1< -6) (L 1< -7) (L 1< -8) (L 1< -9) (L 1< -10) (L 1< -11) (L 1< -12) (L 1< -13) (L 1< -14) (L 1< -15) (L 1< -16) (L 1< -17) (L 1< -18) (L 1< -19) (L 1< -20) (L 1< -21) (L 1< -22) (L 1< -23) (L 1< -24) (L 1< -25) (L 1< -26) (L 1< -27) (L 1< -28) (L 1< -29) (L 1< -30) (L 1< -31) (L 1< -32) (L 1< -33) (L 1< -34) (L 1< -35) (L 1< -36) (L 1< -37)

[0028] Ar 3< is preferably an aromatic ring system with 6 to 30 aromatic ring atoms, which may be substituted with one or more R 4< groups. Ar 3< is particularly preferably selected from phenyl, biphenyl, terphenyl, fluorenyl, fluorenyl-phenyl, naphthyl, naphthyl-phenyl, spirobifluorenyl, spirobifluorenyl-phenyl, pyridyl, pyrimidyl, triazinyl, dibenzofuranyl, dibenzofuranyl-phenyl, benzo-condensed dibenzofuranyl, dibenzothiophenyl, dibenzothiophenyl-phenyl, benzo-condensed dibenzothiophenyl, carbazolyl, carbazolyl-phenyl, and benzo-condensed carbazolyl, and combinations of two, three, or four of these groups, wherein the aforementioned groups may each be substituted with one or more R 4< groups.

[0029] The group Ar 3< preferably does not correspond to either of the formulas (A) and (B).

[0030] Preferred embodiments of Ar 3< are shown below: Ar 3< -1 Ar 3< -2 Ar 3< -3 Ar 3< -4 Ar 3< -5 Ar 3< -6 Ar 3< -7 Ar 3< -8 Ar 3< -9 Ar 3< -10 Ar 3< -11 Ar 3< -12 Ar 3< -13 Ar 3< -14 Ar 3< -15 Ar 3< -16 Ar 3< -17 Ar 3< -18 Ar 3< -19 Ar 3< -20 Ar 3< -21 Ar 3< -22 Ar 3< -23 Ar 3< -24 Ar 3< -25 Ar 3< -26 Ar 3< -27 Ar 3< -28 Ar 3< -29 Ar 3< -30 Ar 3< -31 Ar 3< -32 Ar 3< -33 Ar 3< -34 Ar 3< -35 Ar 3< -36 Ar 3< -37 Ar 3< -38 Ar 3< -39 Ar 3< -40 Ar 3< -41 Ar 3< -42 Ar 3< -43 Ar 3< -44 Ar 3< -45 Ar 3< -46 Ar 3< -47 Ar 3< -48 Ar 3< -49 Ar 3< -50 Ar 3< -51 Ar 3< -52 Ar 3< -53 Ar 3< -54 Ar 3< -55 Ar 3< -56 Ar 3< -57 Ar 3< -58 Ar 3< -59 Ar 3< -60 Ar 3< -61 Ar 3< -62 Ar 3< -63 Ar 3< -64 Ar 3< -65 Ar 3< -66 Ar 3< -67 Ar 3< -68 Ar 3< -69 Ar 3< -70 Ar 3< -71 Ar 3< -72 Ar 3< -73 Ar 3< -74 Ar 3< -75 Ar 3< -76 Ar 3< -77 Ar 3< -78 Ar 3< -79 Ar 3< -80 Ar 3< -81 Ar 3< -82 Ar 3< -83 Ar 3< -84 Ar 3< -85 Ar 3< -86 Ar 3< -87 Ar 3< -88 Ar 3< -89 Ar 3< -90 Ar 3< -91 Ar 3< -92 Ar 3< -93 Ar 3< -94 Ar 3< -95 Ar 3< -96 Ar 3< -94 Ar 3< -95 Ar 3< -96 Ar 3< -97 Ar 3< -98 Ar 3< -99 Ar 3< -100 Ar 3< -101 Ar 3< -102 Ar 3< -103 Ar 3< -104 Ar 3< -105 Ar 3< -106 Ar 3< -107 Ar 3< -108 Ar 3< -109 Ar 3< -110 Ar 3< -111 Ar 3< -112 Ar 3< -113 Ar 3< -114 Ar 3< -115 Ar 3< -116 Ar 3< -117 Ar 3< -118 Ar 3< -119 Ar 3< -120 Ar 3< -121 Ar 3< -122 Ar 3< -123 Ar 3< -124 Ar 3< -125 Ar 3< -126 Ar 3< -127 Ar 3< -128 Ar 3< -129 Ar 3< -130 Ar 3< -131 Ar 3< -132 Ar 3< -133 Ar 3< -134 Ar 3< -135 Ar 3< -136 Ar 3< -137 Ar 3< -138 Ar 3< -139 Ar 3< -140 Ar 3< -141 Ar 3< -142 Ar 3< -143 Ar 3< -144 Ar 3< -145 Ar 3< -146 Ar 3< -147 Ar 3< -148 Ar 3< -149 Ar 3< -150 Ar 3< -151 Ar 3< -152 Ar 3< -153 Ar 3< -154 Ar 3< -155 Ar 3< -156 Ar 3< -157 Ar 3< -158 Ar 3< -159 Ar 3< -160 Ar 3< -161 Ar 3< -162 Ar 3< -163 Ar 3< -164 Ar 3< -165 Ar 3< -166 Ar 3< -167 Ar 3< -168 Ar 3< -169 Ar 3< -170 Ar 3< -171 Ar 3< -172 Ar 3< -173 Ar 3< -174 Ar 3< -175 Ar 3< -176 Ar 3< -177 Ar 3< -178 Ar 3< -179 Ar 3< -180 Ar 3< -181 Ar 3< -182 Ar 3< -183 Ar 3< -184 Ar 3< -185 Ar 3< -186 Ar 3< -187 Ar 3< -188 Ar 3< -189 Ar 3< -190 Ar 3< -191 Ar 3< -192 Ar 3< -193 Ar 3< -194 Ar 3< -195 Ar 3< -196 Ar 3< -197 Ar 3< -198 Ar 3< -199 Ar 3< -200 Ar 3< -201 Ar 3< -202 Ar 3< -203 Ar 3< -204 Ar 3< -205 Ar 3< -206 Ar 3< -207 Ar 3< -208 Ar 3< -209 Ar 3< -210 Ar 3< -211 Ar 3< -212 Ar 3< -213 Ar 3< -214 Ar 3< -215 Ar 3< -216 Ar 3< -217 Ar 3< -218 Ar 3< -219 Ar 3< -220 Ar 3< -221 Ar 3< -222 Ar 3< -223 Ar 3< -224 Ar 3< -225 Ar 3< -226 Ar 3< -227 Ar 3< -228 Ar 3< -229 Ar 3< -230 Ar 3< -231 Ar 3< -232 Ar 3< -233 Ar 3< -234 Ar 3< -235 Ar 3< -236 Ar 3< -237 Ar 3< -238 Ar 3< -239 Ar 3< -240 Ar 3< -241 Ar 3< -242 Ar 3< -243 Ar 3< -244 Ar 3< -245 Ar 3< -246 Ar 3< -247 which at the free positions each have one or more remainders R 4 may be substituted.

[0031] Preferably, R3< and R4< are chosen to be the same or different from H, D, F, CN, Si(R5<)3, N(R5<)2, 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, the aforementioned aromatic ring systems, and the aforementioned heteroaromatic ring systems may each be substituted with one or more R5< groups; and wherein in the aforementioned alkyl 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< -.

[0032] R3 is particularly preferred, as is R4, which is particularly preferred.

[0033] Preferably, R 5< is selected in each instance as the same or different from H, D, F, CN, Si(R 6< ) 3 , N(R 6< ) 2 , 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, the aforementioned aromatic ring systems and the aforementioned heteroaromatic ring systems may each be substituted with one or more R 6< residues; and wherein in the aforementioned alkyl groups one or more CH₂ groups can be replaced by -C=C-, -R₆<C=CR₆<-, Si(R₆<)₂, C=O, C=NR₆<-, -NR₆<-, -O-, -S-, -C(=O)O- or -C(=O)NR₆<-. R₆< is particularly preferred as H.

[0034] Preferably, R 6< is selected in each instance as the same or different from H, D, F, CN, alkyl groups with 1 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< groups can be linked together and form a ring; and wherein the aforementioned alkyl groups, aromatic ring systems and heteroaromatic ring systems can be substituted with F or CN.

[0035] According to the invention, the subunit of formula (I) where the dashed line represents the connection to the rest of the formula, chosen from the following structures: Formel (I-A-45) Formel (I-A-46) Formel (I-A-47) Formel (I-A-49) Formel (I-A-50) Formel (I-A-51) Formel (I-A-53) Formel (I-A-54) Formel (I-A-55) Formel (I-A-57) Formel (I-A-58) Formel (I-A-59) Formel (I-A-60) Formel (I-A-62) Formel (I-A-63) Formel (I-A-64) Formel (I-A-66) Formel (I-A-67) Formel (I-A-68) Formel (I-A-69) Formel (I-A-71) Formel (I-A-72) Formel (I-A-73) Formel (I-A-75) Formel (I-A-76) Formel (I-A-77) Formel (I-A-78) Formel (I-A-80) Formel (I-A-81) Formel (I-A-82) Formel (I-A-84) Formel (I-A-85) Formel (I-A-86) Formel (I-A-87) Formel (I-A-88) Formel (I-A-90) Formel (I-A-91) Formel (I-A-93) Formel (I-A-94) Formel (I-A-95) Formel (I-A-96) Formel (I-A-109) Formel (I-A-111) Formel (I-A-112) Formel (I-A-113) Formel (I-A-114) Formel (I-A-115) Formel (I-A-116) Formel (I-A-118) Formel (I-A-119) Formel (I-A-121) Formel (I-A-122) where the dashed line represents the bond to the N atom in formula (I).

[0036] Preferred embodiments of formula (I) correspond to the following formula (1-2) Formel (I-2) where the following applies to the variables that occur: Y is chosen from C(R 1< ) 2 , Si(R 1< ) 2 , NR 1< , O, and S, preferably from C(R 1< ) 2 , NR 1< , O, and S; The free positions on the benzene rings can each be substituted with a residue R 1<, where R 1< and R 2< are chosen the same or differently from H, D, F, C(=O)R 5< , CN, Si(R 5< ) 3 , N(R 5< ) 2 , 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; where two or more residues R 3< orR4< 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 can each be substituted with one or more R5< residues; and wherein one or more CH2 groups in the aforementioned alkyl, alkoxy, alkenyl, and alkynyl groups can 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 the other variables occurring are defined as above and preferably correspond to their preferred embodiments specified above.

[0037] A preferred embodiment of formula (1-2) corresponds to the following formula (I-2A) Formel (I-2A) where the following applies to the variables that occur: The free positions on the benzene rings can each be substituted with a residue R 1<, and the other variables occurring are defined as above and preferably correspond to their preferred embodiments specified above.

[0038] Preferred embodiments of formula (1-2) correspond to the following formulas (I-2-1) to (I-2-3) Formel (I-2-1) Formel (I-2-2) Formel (I-2-3) where the following applies to the variables that occur: Y is selected from C(R 1< ) 2 , Si(R 1< ) 2 , NR 1< , O, and S, preferably from C(R 1< ) 2 , NR 1< , O, and S; the free positions on the benzene rings can each be substituted with a residue R 1<, and the other variables occurring are defined as above and preferably correspond to their preferred embodiments specified above.

[0039] Preferred embodiments of formula (I-2A) correspond to the following formulas (I-2A-1) to (I-2A-3) Formel (I-2A-1) Formel (I-2A-2) Formel (I-2A-3) where the following applies to the variables that occur: The free positions on the benzene rings can each be substituted with a residue R 1<, and the other variables occurring are defined as above and preferably correspond to their preferred embodiments specified above.

[0040] Preferred specific compounds according to formula (I) are shown in the following table, where compounds that do not meet the claim are marked with #: 1# 2# 3# 4# 5# 6# 7# 8# 9# 10# 11# 12# 13# 14# 15# 16# 17# 18# 19# 20# 21# 22# 23# 24# 25# 26# 27# 28# 29# 30# 31# 32# 33# 34# 35# 36 37 38 39 40 41 42# 43 44 45 46 47 48# 49 50 51 52# 53# 54# 55# 56# 57# 58# 59# 60# 61# 62# 63# 64# 65# 66 67 68 69 70 71 72 73 74 75 76# 77# 78# 79# 80# 81# 82 83 84 85 86 87 88# 89# 90# 91# 92# 93# 94# 95 96 97# 98# 99# 100# 101 102 103 104 105 106 107 108 109 110 111 112# 113# 114 115 116 117 118 119 120# 121 122 123 124 125 126# 127 128 129

[0041] The compounds according to formula (I) can be prepared using known reactions of organic chemistry, in particular using metal-catalyzed coupling reactions such as Suzuki coupling and Buchwald coupling.

[0042] A preferred method for preparing the compounds according to formula (I) is explained in more detail below (Scheme 1). A person skilled in the art may modify and adapt this method as necessary, within the scope of their general knowledge of organic synthetic chemistry.

[0043] According to Scheme 1, in a first step, a biphenyl derivative substituted with two reactive groups X and Y, where group X is in the ortho position to bond between the two phenyl groups, is reacted in a Suzuki reaction with an aromatic or heteroaromatic ring system Ar substituted with a boronic acid group. The Ar ring system is introduced at the position of reactive group Y. In a second step, the resulting intermediate is reacted with an amine compound of the formula HNAr₂ in a Buchwald coupling reaction. The -NAr₂ group is introduced at the position of reactive group X, so that it is in the ortho position to bond between the two phenyl groups. X, Y = reactive groups, preferably Cl, Br, I or other reactive groups such as triflate, tosylate; Ar = aromatic or heteroaromatic ring system; R = organic residue

[0044] The resulting connection can be further modified if necessary.

[0045] The subject matter of the present application is thus a process for the preparation of a compound of formula (I), characterized in that in a first step i) a biphenyl derivative substituted with reactive groups X and Y, wherein group X is in the ortho position for bonding between the two phenyl groups, is reacted with an aromatic or heteroaromatic ring system substituted with a boronic acid group, such that the aromatic or heteroaromatic ring system is introduced in the position of group Y, and that in a second step ii) the intermediate obtained in step i) is reacted with a compound of formula HNAr 2, wherein Ar is selected from aromatic and heteroaromatic ring systems, wherein in this reaction the group -NAr 2 is introduced in the position of group X.

[0046] Preferably, the reaction of step i) is a Suzuki coupling reaction. Preferably, the reaction of step ii) is a Buchwald coupling reaction.

[0047] The intermediate formed in step i) preferably corresponds to a formula (I-Int-1) where Z1< is chosen from CR1< and N, either the same or different in each occurrence, where Z1< is equal to C if a group Ar1< or T is bonded to it; Ar1< is an aromatic ring system with 6 to 30 aromatic ring atoms, either the same or different in each occurrence, which may be substituted with one or more R2< residues; T is chosen from C(R1<)2, Si(R1<)2, NR1<, O, and S; mist is equal to 0 or 1; i is equal to 0, 1, 2, 3, 4, or 5; k is equal to 0, 1, 2, 3, or 4; wherein the sum of k and i is at least equal to 1 and the other variables appearing are defined as above, and wherein X is a reactive group, preferably Cl, Br, I or a triflate or tosylate group, particularly preferably Cl or Br.

[0048] The combination of the formula HNAr 2, which is used in step ii), preferably corresponds to a formula (I-Int-2) where the variables involved are defined as above.

[0049] The compounds of formula (I) described above, especially those substituted with reactive leaving groups such as bromine, iodine, chlorine, boronic acid, or boronic esters, can be used as monomers to generate 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 undergoing cycloaddition, such as a 1,3-dipolar cycloaddition, like dienes or azides, carboxylic acid derivatives, alcohols, and silanes.

[0050] A further aspect of the invention is therefore oligomers, polymers, or dendrimers containing one or more compounds according to formula (I), wherein the bond(s) to the polymer, oligomer, or dendrimer can be located at any position substituted with R< 3< or R< 4< in formula (I). Depending on the linkage of the compound according to formula (I), 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. For the purposes of this invention, a polymer 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 linearly linked structures, the units according to formula (I) can be directly linked to one another, or they can be linked via a bivalent group, for example, a substituted or unsubstituted alkylene group, a heteroatom, or a bivalent aromatic or heteroaromatic group. In branched and dendritic structures, for example, three or more units according to formula (I) can be linked via a trivalent or higher-valent group, for example, a trivalent or higher-valent aromatic or heteroaromatic group, to form a branched or dendritic oligomer or polymer.

[0051] The same preferences apply to the repeating units according to formula (I) in oligomers, dendrimers and polymers as described above for compounds according to formula (I).

[0052] 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 (e.g., according to EP 842208 or WO 2000 / 22026), spirobifluorenes (e.g., according to EP 707020, EP 894107 or WO 2006 / 061181), paraphenylenes (e.g., according to WO 1992 / 18552), carbazoles (e.g., according to WO 2004 / 070772 or WO 2004 / 113468), thiophenes (e.g., according to EP 1028136), dihydrophenanthrenes (e.g., according to WO 2005 / 014689 or WO 2007 / 006383), cis- and trans-indenofluorenes (e.g., according to WO 2004 / 041901 or WO 2004 / 113412), ketones (e.g., according to WO 2005 / 040302), phenanthrenes (e.g., according to WO 2005 / 104264 or WO 2007 / 017066), or several of these units. The polymers, oligomers, and dendrimers usually contain further units, for example, emitting (fluorescent or phosphorescent) units, such as vinyltriarylamines (e.g.,according to WO 2007 / 068325) or phosphorescent metal complexes (e.g. according to WO 2006 / 003000), and / or charge transport units, in particular those based on triarylamines.

[0053] 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 repeat units of formula (I) 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 Suzuki polymerization, the Yamamoto polymerization, the Stille polymerization, and the Hartwig-Buchwald polymerization.

[0054] 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, α-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 ether, triethylene glycol butyl 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.

[0055] The invention therefore further relates to a formulation, in particular a solution, dispersion or emulsion, containing at least one compound according to formula (I) and at least one solvent, preferably an organic solvent. How such solutions can be prepared is known to those skilled in the art and is described, for example, in WO 2002 / 072714, WO 2003 / 019694 and the literature cited therein.

[0056] The compounds according to the invention are suitable for use in electronic devices, in particular in organic electroluminescent devices (OLEDs). Depending on the substitution, the compounds are used in different functions and layers.

[0057] A further object of the invention is therefore the use of the 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).

[0058] As already explained above, a further object of the invention is an electronic device comprising at least one connection according to formula (I). The electronic device is preferably selected from the devices mentioned above.

[0059] Particularly preferred is an organic electroluminescent device (OLED) comprising an anode, cathode and at least one emitting layer, characterized in that at least one organic layer, which may be an emitting layer, a hole-transporting layer or another layer, contains at least one compound according to formula (I).

[0060] In addition to the cathode, anode, and emitting layer, the organic electroluminescent 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 (IDMC 2003, Taiwan; Session 21 OLED (5), T. Matsumoto, T. Nakada, J. Endo, K. Mori, N. Kawamura, A. Yokoi, J. Kido, Multiphoton Organic EL Device Having Charge Generation Layer) and / or organic or inorganic p / n junctions.

[0061] The sequence of layers of the organic electroluminescent device containing the compound of formula (I) is preferably as follows: anode-hole injection layer-hole transport layer-optionally further hole transport layer(s)-optionally electron blocking layer-emitting layer-optionally hole blocking layer-electron transport layer-electron injection layer-cathode. Additional layers may also be present in the OLED.

[0062] 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 the three layers exhibit blue, green, and orange or red emission (for the basic structure, see, e.g., WO 2005 / 011013).The compounds according to the invention are preferably present in a hole transport layer, hole injection layer, electron blocking layer, emitting layer, hole-blocking layer and / or electron transporting layer, particularly preferably in an emitting layer as a matrix material, in a hole-blocking layer and / or in an electron transport layer.

[0063] According to the invention, it is preferred if the compound according to formula (I) is used in an electronic device containing one or more phosphorescent emitting compounds. The compound can be contained in different layers, preferably in a hole transport layer, an electron blocking layer, a hole injection layer, an emitting layer, a hole blocking layer, and / or an electron transport layer. In this case, it is particularly preferred to be contained in an electron blocking layer or in an emitting layer in combination with a phosphorescent emitting compound.

[0064] The term phosphorescent emitting compounds 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, such as a quintet state.

[0065] Suitable phosphorescent emitting compounds (= triplet emitters) are, in particular, compounds that emit light, preferably in the visible range, upon suitable excitation and also contain at least one atom with an atomic number greater than 20, preferably greater than 38 and less than 84, and especially 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 emitting compounds, especially those containing iridium, platinum, or copper. For the purposes of the present invention, all luminescent iridium, platinum, or copper complexes are considered phosphorescent emitting compounds.

[0066] Examples of the emitting compounds described above can be found in applications WO 00 / 70655, WO 01 / 41512, WO 02 / 02714, WO 02 / 15645, EP 1191613, EP 1191612, EP 1191614, WO 05 / 033244, WO 05 / 019373 and US 2005 / 0258742. In general, all phosphorescent complexes used in phosphorescent OLEDs according to the prior art and known to those skilled in the art in the field of organic electroluminescent devices are suitable. Furthermore, those skilled in the art can use other phosphorescent complexes in combination with the compounds according to formula (I) in organic electroluminescent devices without any inventive step. Further examples are listed in the following table:

[0067] In a preferred embodiment of the invention, the compounds according to formula (I) are used as a hole-transporting material. The compounds are then preferably present in a hole-transporting layer. Preferred embodiments of hole-transporting layers are hole transport layers, electron blocking layers, and hole injection layers. It is particularly preferred that at least one compound of formula (I) is present in the electron blocking layer of the device.

[0068] A hole transport layer according to the present application is a layer with a hole transporting function, which is located between the anode and the emitting layer. In particular, it is a hole transporting layer that is neither a hole injection layer nor an electron blocking layer.

[0069] Hole injection layers and electron blocking layers are understood, within the meaning of the present application, as special embodiments of hole-transporting layers. In the case of multiple hole-transporting layers between the anode and the emitting layer, a hole injection layer is a hole-transporting layer that is directly adjacent to the anode or separated from it only by a single coating of the anode. In the case of multiple hole-transporting layers between the anode and the emitting layer, an electron blocking layer is the hole-transporting layer that is directly adjacent to the emitting layer on the anode side.Preferably, the OLED according to the invention comprises two, three or four hole-transporting layers between the anode and the emitting layer, of which preferably at least one contains a compound according to formula (I), and particularly preferably exactly one or two contain a compound according to formula (I).

[0070] If the compound according to formula (I) is used as a hole transport material in a hole transport layer, a hole injection layer or an electron blocking layer, the compound can be used as a pure material, i.e. in a proportion of 100%, in the hole transport layer, or it can be used in combination with one or more other compounds.

[0071] According to a preferred embodiment, a hole-transporting layer containing the compound of formula (I) additionally contains one or more further hole-transporting compounds. These further hole-transporting compounds are preferably selected from triarylamine compounds, particularly preferably from mono-triarylamine compounds. Most preferably, they are selected from the preferred embodiments of hole-transporting materials specified below. In the described preferred embodiment, the compound of formula (I) and the one or more further hole-transporting compounds are preferably each present in a proportion of at least 20%, particularly preferably each present in a proportion of at least 30%.

[0072] 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.

[0073] Particularly preferred embodiments of p-dodends are the compounds disclosed in WO 2011 / 073149, EP 1968131, EP 2276085, EP 2213662, EP 1722602, EP 2045848, DE 102007031220, US 8044390, US 8057712, WO 2009 / 003455, WO 2010 / 094378, WO 2011 / 120709, US 2010 / 0096600, WO 2012 / 095143 and DE 102012209523.

[0074] 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, MoOs, 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.

[0075] The p-doping agents are preferentially distributed in a largely uniform manner within the p-doped layers. This can be achieved, for example, by co-evaporation of the p-doping agent and the hole transport material matrix.

[0076] 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)

[0077] In a further preferred embodiment of the invention, the compound according to formula (I) is used as a hole transport material in combination with a hexaazatriphenylene derivative, as described in US 2007 / 0092755, in an OLED. It is particularly preferred that the hexaazatriphenylene derivative is used in a separate layer.

[0078] In a preferred embodiment of the present invention, the compound of formula (I) is used in an emitting layer as a matrix material in combination with one or more emitting compounds, preferably phosphorescent emitting compounds.

[0079] 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.%.

[0080] 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.%.

[0081] 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.

[0082] 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 hole-transporting properties and the other material is a material with electron-transporting properties. The compound of formula (I) preferably represents the matrix material with hole-transporting properties. Accordingly, if 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, which has electron-transporting properties.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. More detailed information on mixed-matrix systems is contained, inter alia, in application WO 2010 / 108579, the corresponding technical teaching of which is incorporated here.

[0083] 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.

[0084] The mixed-matrix systems can comprise one or more emitting compounds, preferably one or more phosphorescent emitting compounds. In general, mixed-matrix systems are preferably used in phosphorescent organic electroluminescence devices.

[0085] Particularly suitable matrix materials, which can be used in combination with the compounds according to the invention as matrix components of a mixed matrix system, are selected from the preferred matrix materials for phosphorescent emitting compounds listed below, including in particular those which have electron-transporting properties.

[0086] The following are preferred embodiments for the various functional materials of the electronic device.

[0087] 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 understood to be 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. Other preferred emitting compounds are indenofluorenamines or diamines, for example according to WO 2006 / 108497 or WO 2006 / 122630, benzoindenofluorenamines or diamines, for example according to WO 2008 / 006449, and dibenzoindenofluorenamines or diamines, for example according to WO 2007 / 140847, as well as the indenofluorene derivatives with fused aryl groups disclosed in WO 2010 / 012328. Also preferred are the pyrene arylamines disclosed in WO 2012 / 048780 and WO 2013 / 185871.Also preferred are the benzoindenofluorene amines disclosed in WO 2014 / 037077, the benzofluorene amines disclosed in WO 2014 / 106522, the extended benzoindenofluorenes disclosed in WO 2014 / 111269 and in the unpublished application EP 15182993.4, the phenoxazines disclosed in the unpublished applications EP 15181178.3 and EP 15181177.5, and the fluorene derivatives disclosed in WO 2016 / 150544, which are combined with furan units or with thiophene units.

[0088] Materials from various classes of substances are suitable as matrix materials, preferably for fluorescent emitting compounds. Preferred matrix materials are selected from the classes of oligoarylenes (e.g., 2,2',7,7'-tetraphenylspirobifluorene according to EP 676461 or dinaphthylanthracene), in particular oligoarylenes containing fused aromatic groups, oligoarylene vinylenes (e.g., DPVBi or Spiro-DPVBi according to EP 676461), polypodal metal complexes (e.g., according to WO 2004 / 081017), hole-conducting compounds (e.g., according to WO 2004 / 058911), electron-conducting compounds, in particular ketones, phosphine oxides, sulfoxides, etc. (e.g., according to WO 2005 / 084081 and WO 2005 / 084082), and atropisomers (e.g., according to WO 2006 / 048268). the boronic acid derivatives (e.g. according to WO 2006 / 117052) or the benzanthracenes (e.g. according to WO 2008 / 145239).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. Most 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 is understood to be a compound in which at least three aryl groups are bonded together.Preferred are still the anthracene derivatives disclosed in WO 2006 / 097208, WO 2006 / 131192, WO 2007 / 065550, WO 2007 / 110129, WO 2007 / 065678, WO 2008 / 145239, WO 2009 / 100925, WO 2011 / 054442, and EP 1553154, the pyrene compounds disclosed in EP 1749809, EP 1905754 and US 2012 / 0187826, the benzanthracenyl anthracene compounds disclosed in WO 2015 / 158409, the indeno-benzofurans disclosed in the unpublished application EP 15180777.3, and the Phenanthryl-anthracenes disclosed in the as yet unpublished application EP 15182962.9.

[0089] Preferred matrix materials for phosphorescent emitting compounds, besides the compounds of formula (I), are aromatic ketones, aromatic phosphine oxides or aromatic sulfoxides or sulfones, e.g. according to WO 2004 / 013080, WO 2004 / 093207, WO 2006 / 005627 or WO 2010 / 006680, triarylamines, carbazole derivatives, e.g. CBP (N,N-biscarbazolylbiphenyl) or the carbazole derivatives disclosed in WO 2005 / 039246, US 2005 / 0069729, JP 2004 / 288381, EP 1205527 or WO 2008 / 086851, indolocarbazole derivatives, e.g. B. according to WO 2007 / 063754 or WO 2008 / 056746, indenocarbazole derivatives, e.g. according to WO 2010 / 136109, WO 2011 / 000455 or WO 2013 / 041176, azacarbazole derivatives, e.g. according to EP 1617710, EP 1617711, EP 1731584, JP 2005 / 347160, bipolar matrix materials, e.g. according to WO 2007 / 137725, silanes, e.g. according to WO 2005 / 111172, azaborols or boron esters, e.g. according to WO 2006 / 117052, triazine derivatives, e.g. B. according to WO 2010 / 015306, WO 2007 / 063754 or WO 2008 / 056746, zinc complexes, e.g.according to EP 652273 or WO 2009 / 062578, diazasilol or tetraazasilol derivatives, e.g. according to WO 2010 / 054729, diazaphosphol derivatives, e.g. according to WO 2010 / 054730, bridged carbazole derivatives, e.g. according to US 2009 / 0136779, WO 2010 / 050778, WO 2011 / 042107, WO 2011 / 088877 or WO 2012 / 143080, triphenylene derivatives, e.g. according to WO 2012 / 048781, or lactams, e.g. according to WO 2011 / 116865 or WO 2011 / 137951.

[0090] Suitable charge transport materials, such as those that can be used in the hole injection or hole transport layer or electron blocking layer or in the electron transport layer of the electronic device according to the invention, are, in addition to the compounds of formula (I), 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.

[0091] Preferably, the OLED according to the invention comprises two or more different hole-transporting layers. The compound of formula (I) can be used in one, several, or all of the hole-transporting layers. According to a preferred embodiment, the compound of formula (I) is used in exactly one or exactly two hole-transporting layers, and other compounds, preferably aromatic amine compounds, are used in the other hole-transporting layers. Further compounds that, in addition to the compounds of formula (I), are preferably used in hole-transporting layers of the OLEDs according to the invention are, in particular, indenofluorenamine derivatives (e.g., according to WO 06 / 122630 or WO 06 / 100896), the amine derivatives disclosed in EP 1661888, hexaazatriphenylene derivatives (e.g., according to WO 01 / 049806), amine derivatives with fused aromatics (e.g.,according to US 5,061,569), the amine derivatives disclosed in WO 95 / 09147, monobenzoindenofluorenamines (e.g. according to WO 08 / 006449), dibenzoindenofluorenamines (e.g. according to WO 07 / 140847), spirobifluorene amines (e.g. according to WO 2012 / 034627 or WO 2013 / 120577), fluorene amines (e.g. according to WO 2014 / 015937, WO 2014 / 015938, WO 2014 / 015935 and WO 2015 / 082056), spiro-dibenzopyran amines (e.g. according to WO 2013 / 083216), dihydroacridine derivatives (e.g. according to WO 2012 / 150001), spirodibenzofurans and spirodibenzothiophenes, e.g. according to WO 2015 / 022051 and the unpublished applications PCT / EP2015 / 002475 and PCT / EP2016 / 000084, phenanthrene diarylamines, e.g. according to WO 2015 / 131976, spiro-tribenzotropolones, e.g. according to the unpublished application PCT / EP2015 / 002225, spirobifluorenes with meta-phenyldiamine groups, e.g. according to the unpublished application PCT / EP2015 / 002112, spiro-bisacridines, e.g. according to WO 2015 / 158411, xanthene diarylamines, e.g.according to WO 2014 / 072017, and 9,10-dihydroanthracene spiro compounds with diarylamine groups according to WO 2015 / 086108.

[0092] Suitable materials for the electron transport layer include all materials that are used as electron transport materials in electron transport layers according to the prior art. In particular, suitable materials include 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. Further suitable materials are derivatives of the aforementioned compounds as disclosed in JP 2000 / 053957, WO 2003 / 060956, WO 2004 / 028217, WO 2004 / 080975, and WO 2010 / 072300.

[0093] 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.

[0094] 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.

[0095] The device is structured accordingly (depending on the application), contacted, and finally sealed to exclude damaging effects from water and air.

[0096] 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.

[0097] 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).

[0098] 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.

[0099] 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.

[0100] 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 (e.g., light therapy). Beispiele A) Synthesebeispiele Synthesis of the compound Biphenyl-4-yl-(9-phenyl-9H-carbazol-2-yl)-[1,1';3',1"]terphenyl-2-yl-amine* (1-1) and of compounds (1-2) to (1-22)

[0101] * Reference connection Synthesis of intermediate I-1: 2-Bromo-[1,1';3',1"]-terphenyl

[0102] 14.3 g (117 mmol) of phenylboronic acid, 40 g (111.4 mmol) of 2-bromo-3'-iodobiphenyl, and 84 mL of an aqueous 2 MK₂CO₃ solution (168 mmol) are suspended in 400 mL of toluene. 1.2 g (1.2 mmol) of tetrakis(triphenyl)phosphine palladium(0) is added to this suspension. The reaction mixture is heated under reflux for 16 h. After cooling, the organic phase is separated, filtered through silica gel, washed three times with 150 mL of water, and then concentrated to dryness. Filtration of the crude product through silica gel with heptane / acetic acid ester yields 29 g (85%) of 2-bromo-[1,1';3',1"]terphenyl.

[0103] Similarly, the following connections are established: Reagent 1 Reagent 2 product I-2 I-3 I-4 I-5 I-6 I-7 I-8 I-9 I-10 I-11 I-12 Synthesis of intermediate I-13: 5-chloro-9,9-dimethyl-2-phenylfluorene

[0104] Intermediate Stage II-1

[0105] 8.3 g of phenylboronic acid (68 mmol) and 20 g of dibromocarboxylic acid derivative (68 mmol) are suspended in 400 mL of toluene, 160 mL of ethanol, and 80 mL of water. 14.4 g of sodium carbonate are added. The solution is degassed and saturated with nitrogen. It is then treated with 0.79 g (0.68 mmol) of Pd(Ph₃P)₄. The reaction mixture is heated for 4 h under a protective atmosphere (80°C). The mixture is then separated between toluene and water, the organic phase is washed three times with water, and dried and rotated over Na₂SO₄. After filtration of the crude product through silica gel with heptane / ethyl acetate, the remaining residue is recrystallized from ethanol. The yield is 11.0 g (55% of theory).

[0106] 5.9 g of 2-chlorophenylboronic acid (38 mmol) and 11 g of the bromine derivative (38 mmol) are suspended in 200 mL of toluene and 70 mL of water. 7.2 g of sodium carbonate (67.6 mmol) are added. The solution is degassed and saturated with N₂. It is then treated with 140 mg (0.15 mmol) of Pd₂(dba)₃ and 250 mg of SPhos (0.3 mmol). The reaction mixture is heated to boiling for 12 h under a protective atmosphere. The mixture is then separated between toluene and water, the organic phase is washed three times with water, and dried and rotated over Na₂SO₄.

[0107] After filtration of the crude product over silica gel with toluene, the remaining residue is recrystallized from EtOH. The yield is 10.4 g (85% of theory).

[0108] Similarly, the following connections are established: Reagent 1 Boronic acid 1 Boronic acid 2 product II-2 II-3 ii-4 Intermediate Level I-13

[0109] 10.4 g (32.2 mmol) of intermediate II-1 are dissolved in 100 mL of dried THF in a heated flask. The solution is saturated with N₂. The clear solution is cooled to -5°C, and then 32.2 mL (96.7 mmol) of a 3M methylmagnesium chloride solution are added. The reaction mixture is slowly warmed to room temperature and then quenched with ammonium chloride. The mixture is then divided between ethyl acetate and water, the organic phase is washed three times with water, dried over Na₂SO₄, and rotated. The rotated solution is dissolved in toluene and mixed with 8 g of Amberlyst 15. The mixture is heated to 110°C and held at this temperature for 4 h.

[0110] A white solid precipitates out. The mixture is then cooled to room temperature, the precipitated solid is filtered off, and the mixture is washed with heptane. The residue is dried under vacuum at 40°C. After filtration of the crude product through silica gel with a 1:1 heptane:ethyl acetate solution, 9.3 g (90% of the theoretical yield) of the product is obtained.

[0111] Similarly, the following connections are established: Reagent 1 Reagent 2 product I-13 MeMgCl I-14 PhLi I-15 MeMgBr I-16 MeMgCl 1-17 Synthesis of biphenyl-4-yl-(9-phenyl-9H-carbazol-2-yl)-[1,1';3',1"]terphenyl-2-yl-amine) (compound 1-1) and compounds (1-2) to (1-14)

[0112] 16.2 g of biphenyl-4-yl-(9-phenyl-9H-carbazol-2-yl)amine (48.5 mmol) and 15 g of 2-bromo-[1,1';3',1"]-terphenyl (48.5 mmol) are dissolved in 300 mL of toluene. The solution is degassed and saturated with N₂. It is then treated with 1.94 mL (1.94 mmol) of a 1 M tri-tert-butylphosphine solution and 0.89 g (0.97 mmol) of Pd₂(dba)₃. Subsequently, 7.0 g of sodium tert-butoxide (72.8 mmol) are added. The reaction mixture is heated to boiling for 5 h under a protective atmosphere. The mixture is then dispersed between toluene and water, the organic phase is washed three times with water, dried over Na₂SO₄, and rotated. After filtration of the crude product over silica gel with The remaining residue of heptane / toluene is recrystallized with toluene. The residue, 22.3 g (72% of the theoretical value), is then sublimed under high vacuum.

[0113] Similarly, the following connections are established: Reagent 1 Reagent 2 product 1-2* 1-3* 1-4 1-5 1-6 1-7 1-8* 1-9* 1-10* 1-11* 1-12* 1-13* 1-14 1-15* 1-16* 1-17 1-18 1-19* 1-20* 1-21* 1-22* * Reference connection B) Device Examples

[0114] Example OLEDs are manufactured according to the following general specification:

[0115] Glass platelets coated with a 50 nm thick layer of structured ITO (indium tin oxide) serve as substrates. The following layer structure is applied to this: hole injection layer (HIL) / hole transport layer (HTL) / electron blocking layer (EBL) / emission layer (EML) / electron transport layer (ETL) / electron injection layer (EIL) / cathode. The cathode consists of a 100 nm thick aluminum layer. The materials used in the corresponding layers of the example OLEDs are listed in Table 1, and the chemical structures of these materials are given in Table 3.

[0116] The materials are deposited in a vacuum chamber using thermal vapor deposition. The emission layer always consists of two matrix materials (hosts) and an emitting dopant (emitter), which is added to the matrix materials in a specific volume fraction through co-evaporation. The percentages given for the materials are therefore to be understood as volume percent. The same applies to layers other than the emission layer. These can also contain two or more materials.

[0117] The OLEDs are characterized according to standard procedures. For this, the electroluminescence spectra and the external quantum efficiency (EQE, measured in %) are determined as a function of luminance, calculated from current / voltage / luminance characteristic curves (IUL curves). Lambertian emission characteristics are assumed. Furthermore, the operating voltage (U, in V) is determined.

[0118] EQE @ 1000 cd / m² represents the external quantum efficiency at an operating luminance of 1000 cd / m². EQE @ 10 mA / cm² represents the external quantum efficiency at a current density of 10 mA / cm². Use of the compounds in the EBL of green phosphorescent OLEDs

[0119] OLED examples V1 to E12 have the layer structure shown in Table 1a, with one of the compounds 1-1*, 1-2*, 1-3*, 1-4, 1-6, 1-7, 1-10*, 1-14, 1-15*, 1-16*, 1-17 and 1-18 present in the EBL (reference compounds are marked with *).

[0120] In all cases, good results are achieved with the OLEDs regarding operating voltage and EQE (Table 2a). Furthermore, the OLEDs according to the invention exhibit a good lifetime.

[0121] OLEDs with comparable performance data as shown in Table 2a can also be obtained using compounds with N-bound carbazole, such as compound 1-13. Table 1a: Structure of OLEDs Example. HIL HTL EBL EML HBL ETL Urgent V1 HTM: F4TCNQ(5%) 20 nm HTM 215 nm HTMV1 10 nm H1 (59%): H2(29%): TEG(12%) 30 nm ETM 10 nm ETM:LiQ(50%) 30 nm LiQ 1 nm E1 so so 1-1 so so so so 10 nm E2 so so 1-2 so so so so 10 nm E3 so so 1-3 so so so so 10 nm E4 so so 1-4 so so so so 10 nm E5 so so 1-6 so so so so 10 nm E6 so so 1-7 so so so so 10 nm E7 so so 1-10 so so so so 10 nm E8 so so 1-14 so so so so 10 nm E9 so so 1-15 so so so so 10 nm E10 so so 1-16 so so so so 10 nm E11 so so 1-17 so so so so 10 nm E12 so so 1-18 so so so so 10 nm Table 2a: Data of the OLEDs Example U @ 1000 cd / m²< EQE @ 1000 cd / m² [V] % V1 3.3 15.2 E1 3.0 17.2 E2 3.1 19.1 E3 3.1 17.4 E4 3.0 17.1 E5 3.4 16.6 E6 3.0 17.1 E7 3.2 18.8 E8 3.2 16.3 E9 3.1 17.9 E10 3.2 18.5 E11 2.9 17.3 E12 2.9 17.4 Use of the compounds in the HIL and HTL of blue fluorescent OLEDs

[0122] OLED examples E13 to E15 have the layer structure shown in Table 1b, with one of the compounds 1-15, 1-17 and 1-18 present in the hole-transporting layers HIL and HTL.

[0123] In all cases, the OLEDs achieve good results with regard to operating voltage and EQE (Table 2b). Furthermore, the OLEDs exhibit a good lifespan. Table 1b: Structure of OLEDs Example. HIL HTL EBL EML ETL Urgent Thickness / nm Thickness / nm Thickness / nm Thickness / nm Thickness / nm Thickness / nm E13 1-15: F4TCNQ (5%) 1-15 EBL 10 nm H:SEB(5%) 20 nm ETM:LiQ(50%) 30 nm LiQ 1 nm 20 nm 180 nm E14 1-17: F4TCNQ (5%) 1-17 so so so so 20 nm 180 nm E15 1-18: F4TCNQ (5%) 1-18 so so so so 20 nm 180 nm Table 2b: OLED data U @ 10 mA / cm 2< EQE @ 10 mA / cm² [V] [%] E13 4.8 9.0 E14 4.5 8.1 E15 4.4 8.5 Use of the compounds in the EBL of blue fluorescent OLEDs

[0124] OLED examples E16 and E17 have the layer structure shown in Table 1c, wherein one of the compounds 1-15 and 1-16 according to the invention is present in the EBL in each case.

[0125] In all cases, the OLEDs achieve good results with regard to operating voltage and EQE (Table 2c). Furthermore, the OLEDs exhibit a good lifespan. Table 1c: Structure of OLEDs Example. HIL HTL EBL EML ETL Urgent Thickness / nm Thickness / nm Thickness / nm Thickness / nm Thickness / nm Thickness / nm E-16 HTM: F4TCNQ (5%) HTM 180 nm 1-15 H:SEB(5%) 20 nm ETM:LiQ(50%) 30 nm LiQ 1 nm 20 nm 10 nm E-17 so so 1-16 so so so 10 nm Table 2c: OLED data U @ 10 mA / cm 2< EQE @ 10 mA / cm² [V] [%] E-16 3.8 8.5 E-17 3.8 9.3 Table 3: Structures of the materials F4TCNQ HTM H1 H2 TEG ETM EBL H SEB LiQ HTMV1 1-1 1-2 1-3 1-4 1-6 1-7 1-10 1-14 1-15 1-16 1-17 1-18

Claims

1. Compound of the formula (I) where the sub-unit of the formula (I) is selected from the following structures: formula (I-A-45) formula (I-A-46)formula (I-A-47) formula (I-A-49)formula (I-A-50)formula (I-A-51) formula (I-A-53)formula (I-A-54) formula (I-A-55)formula (I-A-57) formula (I-A-58)formula (I-A-59)formula (I-A-60) formula (I-A-62)formula (I-A-63) formula (I-A-64)formula (I-A-66) formula (I-A-67)formula (I-A-68)formula (I-A-69) formula (I-A-71)formula (I-A-72) formula (I-A-73)formula (I-A-75) formula (I-A-76)formula (I-A-77)formula (I-A-78) formula (I-A-80)formula (I-A-81) formula (I-A-82)formula (I-A-84) formula (I-A-85)formula (I-A-86)formula (I-A-87) formula (I-A-88)formula (I-A-90) formula (I-A-91)formula (I-A-93) formula (I-A-94)formula (I-A-95)formula (I-A-96) formula (I-A-109)formula (I-A-111) formula (I-A-112)formula (I-A-113)formula (I-A-114) formula (I-A-115)formula (I-A-116) formula (I-A-118)formula (I-A-119) formula (I-A-121)formula (I-A-122) where the dashed line represents the bond to the N atom in formula (I), and where the following applies to the variables occurring: Ar2 corresponds to a formula (A) or (B) Z2 is on each occurrence, identically or differently, CR3 or N, where Z2 is equal to C if a group L1 is bonded thereto; L1 is a single bond, or an aromatic ring system having 6 to 30 aromatic ring atoms, which may be substituted by one or more radicals R3, or a heteroaromatic ring system having 5 to 30 aromatic ring atoms, which may be substituted by one or more radicals R3; Ar3 corresponds to a formula (A), a formula (B), or is an aromatic ring system having 6 to 30 aromatic ring atoms, which may be substituted by one or more radicals R4, or a heteroaromatic ring system having 5 to 30 aromatic ring atoms, which may be substituted by one or more radicals R4; R3, R4 are selected on each occurrence, identically or differently, from H, D, F, 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 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; where two or more radicals R3 and R4, respectively, may be linked to one another and may form a ring; where the said alkyl, alkoxy, alkenyl and alkynyl groups and the said aromatic ring systems and heteroaromatic ring systems may in each case be substituted by one or more radicals R5; and where one or more CH2 groups in the said alkyl, alkoxy, alkenyl and alkynyl groups may be replaced 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 selected on each occurrence, identically or differently, from H, D, F, C(=O)R6, CN, Si(R6)3, N(R6)2, 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; where two or more radicals R5 may be linked to one another and may form a ring; where the said alkyl, alkoxy, alkenyl and alkynyl groups and the said aromatic ring systems and heteroaromatic ring systems may in each case be substituted by one or more radicals R6; and where one or more CH2 groups in the said alkyl, alkoxy, alkenyl and alkynyl groups may be replaced 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 selected on each occurrence, identically or differently, from H, D, F, 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; where two or more radicals R6 may be linked to one another and may form a ring; and where the said alkyl, alkoxy, alkenyl and alkynyl groups, aromatic ring systems and heteroaromatic ring systems may be substituted by F or CN.

2. Compound according to Claim 1, characterised in that Ar2 is selected from groups of the following formulae Ar2-1Ar2-2Ar2-3 Ar2-4Ar2-5Ar2-6 Ar2-7Ar2-8Ar2-9 Ar2-10Ar2-11Ar2-12 Ar2-13Ar2-14Ar2-15 Ar2-16Ar2-17Ar2-18 Ar2-19Ar2-20Ar2-21 Ar2-22Ar2-23Ar2-24 Ar2-25Ar2-26Ar2-27 Ar2-28Ar2-29Ar2-30 Ar2-31Ar2-32Ar2-33 Ar2-34Ar2-35Ar2-36 Ar2-37Ar2-38Ar2-39 Ar2-40Ar2-41Ar2-42 Ar2-43Ar2-44Ar2-45 Ar2-46Ar2-47Ar2-48 Ar2-49Ar2-50Ar2-51 Ar2-52Ar2-53Ar2-54 Ar2-55Ar2-56Ar2-57 Ar2-58Ar2-59Ar2-60 Ar2-61Ar2-62Ar2-63 Ar2-64Ar2-65Ar2-66 Ar2-67Ar2-68Ar2-69 Ar2-70Ar2-71Ar2-72 Ar2-73Ar2-74Ar2-75 Ar2-763. Compound according to Claim 1 or 2, characterised in that Ar3 is selected from phenyl, biphenyl, terphenyl, fluorenyl, fluorenyl-phenyl, naphthyl, naphthyl-phenyl, spirobifluorenyl, spirobifluorenyl-phenyl, pyridyl, pyrimidyl, triazinyl, dibenzofuranyl, dibenzofuranyl-phenyl, benzo-fused dibenzofuranyl, dibenzothiophenyl, dibenzothiophenyl-phenyl, benzo-fused dibenzothiophenyl, carbazolyl, carbazolyl-phenyl and benzo-fused carbazolyl, and combinations of two, three or four of these groups, where the said groups may in each case be substituted by one or more radicals R4.

4. Compound according to one or more of Claims 1 to 3, characterised in that R3 and R4 are selected on each occurrence, identically or differently, from H, D, F, CN, Si(R5)3, N(R5)2, 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; where the said alkyl groups, the said aromatic ring systems and the said heteroaromatic ring systems may in each case be substituted by one or more radicals R5; and where one or more CH2 groups in the said alkyl groups may be replaced by -C≡C-, -R5C=CR5-, Si(R5)2, C=O, C=NR5, -NR5-, -O-, -S-, -C(=O)O- or -C(=O)NR5-.

5. Process for the preparation of a compound according to one or more of Claims 1 to 4, characterised in that, in a first step i), a biphenyl derivative which is substituted by reactive groups X and Y, where group X is present in the ortho position to the bond between the two phenyl groups, is reacted with an aromatic or heteroaromatic ring system which is substituted by a boronic acid group, so that the aromatic or heteroaromatic ring system is introduced in the position of group Y, and in that, in a second step ii), the intermediate obtained in step i) is reacted with a compound of the formula HNAr2, where Ar is selected from aromatic ring systems and heteroaromatic ring systems, where the group -NAr2 is introduced in the position of group X in this reaction.

6. Oligomer, polymer or dendrimer containing one or more compounds according to one or more of Claims 1 to 4, where the bond(s) to the polymer, oligomer or dendrimer can be localised at any desired positions in formula (I) that are substituted by R3 or R4.

7. Formulation comprising at least one compound according to one or more of Claims 1 to 4 and at least one solvent.

8. Electronic device containing at least one compound according to one or more of Claims 1 to 4.

9. Electronic device according to Claim 8, characterised in that it is an organic electroluminescent device comprising anode, cathode and at least one emitting layer, where at least one organic layer of the device, which can be an emitting layer or a hole-transporting layer, comprises the at least one compound.

10. Device according to Claim 9, characterised in that it comprises at least one electron-blocking layer which comprises at least one compound of the formula (I).

11. Use of a compound according to one or more of Claims 1 to 4 in an electronic device.