Materials for organic electroluminescent devices

Abstract

The present invention relates to compounds which are suitable for use in electronic devices, and to electronic devices, in particular organic electroluminescent devices, comprising these compounds. The compounds have a dibenzofuran, dibenzothiophene or a fluorene group substituted in the 1-position, either directly or through a linking group, to a carbon atom of a heteroaromatic group with one or two nitrogen atoms in a bicyclic 6/6 core, or to a carbon or nitrogen atom of a heteroaromatic group with two nitrogen atoms in a bicyclic 5/6 core and is further substituted with a group selected from dibenzofuran, dibenzothiophene, fluorene or carbazole.

Claims

1. An oligomer, polymer or dendrimer containing one or more of the compounds according to Formula (1) or (2): ##STR00703## where: X is oxygen, sulfur or CZ.sub.1Z.sub.2; Y is oxygen, sulfur, CZ.sub.1Z.sub.2 or NAr.sub.1; Z.sub.1 and Z.sub.2 are on each occurrence, identically or differently, H, D, F, a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 C atoms or a straight-chain alkenyl or alkynyl group having 2 to 40 C atoms or a branched or cyclic alkyl, alkenyl, alkynyl, alkoxy or thioalkoxy group having 3 to 40 C atoms, each of which may be substituted by one or more radicals R.sub.5, where one or more, non-adjacent CH.sub.2 groups may be replaced by (R.sub.5)C═C(R.sub.5), C≡C, Si(R.sub.5).sub.2, Ge(R.sub.5).sub.2, Sn(R.sub.5).sub.2, C═O, C═S, C═Se, C═N(R.sub.5), P(═O)(R.sub.5), SO, SO.sub.2, N(R.sub.5).sub.2, O, S or CON(R.sub.5).sub.2 and where one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO.sub.2, or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sub.5, or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R.sub.5, where Z.sub.1 and Z.sub.2 may be connected together to form a spiro ring system; R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is on each occurrence, identically or differently, selected from the group consisting of H, D, F, Cl, Br, I, CN, Si(R.sub.5).sub.3, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl with 3-40 C atoms which may be substituted by one or more radicals R.sub.5, wherein each one or more non-adjacent CH.sub.2 groups by may be replaced Si(R.sub.5).sub.2, C═NR.sub.5, P(═O)(R.sub.5), SO, SO.sub.2, NR.sub.5, O, S or CONR.sub.5 and where one or more H atoms may be replaced by D, F, Cl, Br or I, an aromatic or heteroaromatic ring system having 6 to 40 carbon atoms which may be substituted by one or more radicals R.sub.5, an aryloxy group having 5 to 60 aromatic ring atoms which may be substituted by one or more radicals R.sub.5, or an aralkyl group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R.sub.5, where two or more adjacent substituents R.sub.1, R.sub.2, R.sub.3 and R.sub.4 can form a mono- or poly-cyclic, aliphatic, aromatic or heteroaromatic ring system with one another and which may be substituted with one or more radicals R.sub.5; R.sub.5 is selected from the group consisting of H, D, F, an aliphatic hydrocarbon radical having 1 to 20 carbon atoms or an aromatic or heteroaromatic ring system having 5 to 30 C atoms; Ar.sub.1 is an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, which may be substituted by one or more radicals R.sub.5 and where optionally two or more adjacent substituents R.sub.5 can form a mono- or polycyclic, aliphatic, aromatic or heteroaromatic ring system with one another; a, b, c are on each occurrence, identically or differently, are 0, 1, 2 or 3, where a is not 3 in Formula (2), and d is independently 0, 1, 2, 3 or 4; L.sub.1 and L.sub.2 are on each occurrence, identically or differently, a direct bond or an aromatic or heteroaromatic ring system having 5-30 aromatic ring atoms, which may be substituted by one or more non-aromatic radicals R.sub.5; A is a heterocyclic group selected from the group of Formula A.sub.1, ##STR00704## where only one or two of B are nitrogen atoms and the others are carbon atoms, R.sub.1 and R.sub.2 are as previously defined, e is 0, 1, 2 or 3, f is 0, 1, 2, 3 or 4, and wherein A.sub.1 is connected to the remainder of the compound through a carbon atom; or A is a heterocyclic group selected from the group of Formula A2 or A3: ##STR00705## where R.sub.1, R.sub.2, e and f are as previously defined; and Ar.sub.2 is an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, which may be substituted by one or more radicals R.sub.5 and where optionally two or more adjacent substituents R.sub.5 can form a mono- or polycyclic, aliphatic, aromatic or heteroaromatic ring system with one another; or A is a heterocyclic group according to A.sub.4: ##STR00706## where R.sub.2, e and f are as previously defined; and R.sub.6 is the same as R.sub.1 but excluding H or D, where one or more bonds from the compound to the polymer, oligomer or dendrimer are present instead of substituents at one or more positions.

2. The oligomer, polymer or dendrimer according to claim 1, wherein A.sub.1 is according to formula W: ##STR00707## where only one or two of Q are nitrogen atoms and the others are carbon atoms.

3. The oligomer, polymer or dendrimer according to claim 1, wherein X is oxygen and Y is NAr.sub.1.

4. The oligomer, polymer or dendrimer according to claim 1, wherein c is 0, d is 0 or 2 and when d is 2, the two R.sub.4 groups are adjacent and form a monocyclic- or polycyclic, aromatic or heteroaromatic annulated ring system.

5. The oligomer, polymer or dendrimer according to claim 1, wherein the compound is according to any one of Formulae (11) to (18); ##STR00708## where the symbols and indices are defined as in claim 1.

6. The oligomer, polymer or dendrimer according to claim 1, wherein the compound contains no condensed aryl or heteroaryl groups in which more than two six-membered rings are condensed directly onto one another.

7. A formulation comprising the oligomer, polymer or dendrimer according to claim 1 and at least one solvent.

8. An electronic device comprising the oligomer, polymer or dendrimer according to claim 1.

9. The electronic device according to claim 8, wherein the device is selected from the group consisting of organic electroluminescent devices, organic integrated circuits, organic field-effect transistors, organic thin-film transistors, organic light-emitting transistors, organic solar cells, dye-sensitised organic solar cells, organic optical detectors, organic photoreceptors, organic field-quench devices, light-emitting electrochemical cells, organic laser diodes and organic plasmon emitting devices.

10. An organic electroluminescent device which comprises the oligomer, polymer or dendrimer according to claim 1 is employed as matrix material for phosphorescent or fluorescent emitters and/or in an electron-blocking or exciton-blocking layer and/or in a hole-transport layer and/or in a hole-blocking layer and/or in a hole-blocking or electron-transport layer.

11. The oligomer, polymer or dendrimer according to claim 2, wherein one Q is nitrogen so that W group is according to A.sub.1-a or A.sub.1-b or where two Q are nitrogen so that W is according to any of A.sub.1-c, A.sub.1-d and A.sub.1-e: ##STR00709## R.sub.1 and R.sub.2, is on each occurrence, identically or differently, selected from the group consisting of H, D, F, Cl, Br, I, CN, Si(R.sub.5).sub.3, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl with 3-40 C atoms which may be substituted by one or more radicals R.sub.5, wherein each one or more non-adjacent CH.sub.2 groups by may be replaced Si(R.sub.5).sub.2, C═NR.sub.5, P(═O)(R.sub.5), SO, SO.sub.2, NR.sub.5, O, S or CONR.sub.5 and where one or more H atoms may be replaced by D, F, Cl, Br or I, an aromatic or heteroaromatic ring system having 6 to 40 carbon atoms which may be substituted by one or more radicals R.sub.5, an aryloxy group having 5 to 60 aromatic ring atoms which may be substituted by one or more radicals R.sub.5, or an aralkyl group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R.sub.5, where two or more adjacent substituents R.sub.1 and R.sub.2 can form a mono- or polycyclic, aliphatic, aromatic or heteroaromatic ring system with one another and which may be substituted with one or more radicals R.sub.5; R.sub.5 is selected from the group consisting of H, D, F, an aliphatic hydrocarbon radical having 1 to 20 carbon atoms or an aromatic or heteroaromatic ring system having 5 to 30 C atoms; e is 0, 1, 2 or 3; f is 0, 1, 2, 3 or 4; h is 0, 1 or 2; and i is 0 or 1.

12. The oligomer, polymer or dendrimer according to claim 11, wherein W group is A.sub.1-a or A.sub.1-b.

13. The oligomer, polymer or dendrimer according to claim 11, wherein W group is A.sub.1-c or A.sub.1-d.

14. The oligomer, polymer or dendrimer according to claim 11, wherein W group is A.sub.1-e.

15. A compound according to Formula (1) or (2): ##STR00710## where: X is oxygen, sulfur or CZ.sub.1Z.sub.2; Y is oxygen, sulfur, CZ.sub.1Z.sub.2 or NAr.sub.1; Z.sub.1 and Z.sub.2 are on each occurrence, identically or differently, H, D, F, a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 C atoms or a straight-chain alkenyl or alkynyl group having 2 to 40 C atoms or a branched or cyclic alkyl, alkenyl, alkynyl, alkoxy or thioalkoxy group having 3 to 40 C atoms, each of which may be substituted by one or more radicals R.sub.5, where one or more, non-adjacent CH.sub.2 groups may be replaced by (R.sub.5)C═C(R.sub.5), C≡C, Si(R.sub.5).sub.2, Ge(R.sub.5).sub.2, Sn(R.sub.5).sub.2, C═O, C═S, C═Se, C═N(R.sub.5), P(═O)(R.sub.5), SO, SO.sub.2, N(R.sub.5).sub.2, O, S or CON(R.sub.5).sub.2 and where one or more H atoms may be replaced by D, F, Cl, Br, I, CN or NO.sub.2, or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sub.5, or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R.sub.5, where Z.sub.1 and Z.sub.2 may be connected together to form a spiro ring system; R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is on each occurrence, identically or differently, selected from the group consisting of H, D, F, Cl, Br, I, CN, Si(R.sub.5).sub.3, a straight-chain alkyl, alkoxy or thioalkyl group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkyl with 3-40 C atoms which may be substituted by one or more radicals R.sub.5, wherein each one or more non-adjacent CH.sub.2 groups by may be replaced Si(R.sub.5).sub.2, C═NR.sub.5, P(═O)(R.sub.5), SO, SO.sub.2, NR.sub.5, O, S or CONR.sub.5 and where one or more H atoms may be replaced by D, F, Cl, Br or I, an aromatic or heteroaromatic ring system having 6 to 40 carbon atoms which may be substituted by one or more radicals R.sub.5, an aryloxy group having 5 to 60 aromatic ring atoms which may be substituted by one or more radicals R.sub.5, or an aralkyl group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R.sub.5, where two or more adjacent substituents R.sub.1, R.sub.2, R.sub.3 and R.sub.4 can form a mono- or poly-cyclic, aliphatic, aromatic or heteroaromatic ring system with one another and which may be substituted with one or more radicals R.sub.5; R.sub.5 is selected from the group consisting of H, D, F, an aliphatic hydrocarbon radical having 1 to 20 carbon atoms or an aromatic or heteroaromatic ring system having 5 to 30 C atoms; Ar.sub.1 is an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, which may be substituted by one or more radicals R.sub.5 and where optionally two or more adjacent substituents R.sub.5 can form a mono- or polycyclic, aliphatic, aromatic or heteroaromatic ring system with one another; a, b, c are on each occurrence, identically or differently, are 0, 1, 2 or 3, where a is not 3 in Formula (2), and is independently 0, 1, 2, 3 or 4; L.sub.1 and L.sub.2 are on each occurrence, identically or differently, a direct bond or an aromatic or heteroaromatic ring system having 5-30 aromatic ring atoms, which may be substituted by one or more non-aromatic radicals R.sub.5; A is a heterocyclic group selected from the group of Formula A.sub.2 or A.sub.3: ##STR00711## where R.sub.1, R.sub.2, e and f are as previously defined; and Ar.sub.2 is an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, which may be substituted by one or more radicals R.sub.5 and where optionally two or more adjacent substituents R.sub.5 can form a mono- or polycyclic, aliphatic, aromatic or heteroaromatic ring system with one another; or A is a heterocyclic group according to A.sub.4: ##STR00712## e is 0, 1, 2 or 3 and f is 0, 1, 2, 3 or 4 and R.sub.6 is the same as R.sub.1 but excluding H or D.

16. The compound according to claim 15, wherein X is oxygen and Y is NAr.sub.1.

17. The compound according to claim 15, wherein L.sub.1 is a direct bond or a phenylene group.

18. The compound according to claim 15, wherein L.sub.2 is a direct bond or a phenylene group.

19. The compound according to claim 15, wherein whenever X or Y is CZ.sub.1Z.sub.2, Z.sub.1 and Z.sub.2 are identical alkyl groups of 1-10 carbon atoms or aryl groups of between 6-30 carbon atoms.

20. The compound according to claim 15, wherein c is 0, d is 0 or 2 and when d is 2, the two R.sub.4 groups are adjacent and form a monocyclic- or polycyclic, aromatic or heteroaromatic annulated ring system.

21. The compound according to claim 15, wherein the compound contains no condensed aryl or heteroaryl groups in which more than two six-membered rings are condensed directly onto one another.

22. An oligomer, polymer or dendrimer containing one or more of the compounds according to claim 15, where one or more bonds from the compound to the polymer, oligomer or dendrimer are present instead of substituents at one or more positions.

23. A formulation comprising at least one compound according to claim 15 and at least one solvent.

24. An electronic device comprising the compound according to claim 15.

25. The electronic device according to claim 24, wherein the device is selected from the group consisting of organic electroluminescent devices, organic integrated circuits, organic field-effect transistors, organic thin-film transistors, organic light-emitting transistors, organic solar cells, dye-sensitised organic solar cells, organic optical detectors, organic photoreceptors, organic field-quench devices, light-emitting electrochemical cells, organic laser diodes and organic plasmon emitting devices.

26. An organic electroluminescent device which comprises the compound according to claim 15 is employed as matrix material for phosphorescent or fluorescent emitters and/or in an electron-blocking or exciton-blocking layer and/or in a hole-transport layer and/or in a hole-blocking layer and/or in a hole-blocking or electron-transport layer.

Description

EXAMPLES

(1) The following syntheses are carried out, unless indicated otherwise, under a protective-gas atmosphere in dried solvents. The solvents and reagents can be purchased from ALDRICH or ABCR. The numbers indicated in the case of the starting materials which are not commercially available are the corresponding CAS numbers.

(2) Generally, there are two general processes for forming compounds of formulae (1) or (2). The first (illustrated in Scheme 2) is where an intermediate with a group containing X (i.e. dibenzofuran, dibenzothiophene or a fluorene group) and the group containing Y (i.e. dibenzofuran, dibenzothiophene, fluorene or carbazole) is obtained by a C—C coupling, such as Suzuki, Negishi, Yamamoto, Grignard-Cross, Stille, Hartwig-Buchwald or Ullmann, between the two groups. The heterocyclic A (or L.sub.1-A) group is added to this intermediate by subsequent functionization (i.e. halogenation, followed by formation of a boron containing group) and another C—C coupling reaction with A (or L.sub.1-A) compound. In the case where A is a benzotriazole attached via nitrogen, the coupling reaction is by any known C—N coupling reactions including both a nucleophilic aromatic substitution reaction or a Pd-catalysed coupling reaction. Alternatively, a second process (illustrated in Schemes 1 and 3) is where the A (or L.sub.1-A) group is attached to the group containing X by any of same methods described above. The resulting intermediate is then functionized by any of the methods described for the first process, and the group containing Y is then added to the intermediate by a C—C coupling reaction. For example, some of the compounds of the invention may be made by the following synthetic schemes:

(3) ##STR00328##

(4) ##STR00329##

(5) ##STR00330##

Synthesis Examples

a) 4-bromo-9-methyl-9-phenyl-9H-fluorene

(6) ##STR00331##

(7) 30 g (94 mmol) of 2,2′-dibromobiphenyl are dissolved in 200 ml of dried THF in a flask which has been dried by heating. The reaction mixture is cooled to −78° C. 37.7 ml of a 2.5 M solution of n-butyllithium in hexane (94 mmol) are slowly added dropwise (duration: about 1 h) at this temperature. The batch is stirred at −70° C. for a further 1 h. 11.1 ml of acetophenone (94 mmol) are subsequently dissolved in 100 ml of THF and added dropwise at −70° C. When the addition is complete, the reaction mixture is slowly warmed to room temperature, quenched using NH.sub.4Cl and subsequently evaporated in a rotary evaporator. 300 ml of acetic acid are carefully added to the evaporated solution, and 50 ml of fuming HCl are subsequently added. The batch is heated to 75° C. and kept there for 6 h, during which a white solid precipitates out.

b) 4-bromo-9,9-diphenyl-9H-fluorene

(8) ##STR00332##

(9) 37 g (152 mmol) of 2,2′-dibromobiphenyl are dissolved in 300 ml of dried THF in a flask which has been dried by heating. The reaction mixture is cooled to −78° C. 75 ml of a 15% solution of n-butyllithium in hexane (119 mmol) are slowly added dropwise (duration: about 1 hour) at this temperature. The batch is stirred at −70° C. for a further 1 h. 21.8 g of benzophenone (119 mmol) are subsequently dissolved in 100 ml of THF and added dropwise at −70° C. When the addition is complete, the reaction mixture is slowly warmed to room temperature, quenched using NH.sub.4Cl and subsequently evaporated in a rotary evaporator. 510 ml of acetic acid are carefully added to the evaporated solution, and 100 ml of fuming HCl are subsequently added. The batch is heated to 75° C. and kept at this temperature for 4 h, during which a white solid precipitates out. The batch is then cooled to room temperature, and the solid which has precipitated out is filtered off with suction and rinsed with methanol. The residue is dried at 40° C. in vacuo. The yield is 33.2 g (83 mmol) (70% of theory).

(10) The following brominated compounds b1-b3 were prepared analogously:

(11) TABLE-US-00002 Reactant 1 Reactant 2 Product Yield b1 78% b2 70% b3 0 82%

c) 6-Bromo-2-fluoro-2′-methoxy-biphenyl

(12) ##STR00342##

(13) 200 g (664 mmol) of 1-bromo-3-fluoro-2-iodobenzene, 101 g (664 mmol) of 2-methoxyphenylboronic acid and 137.5 g (997 mmol) of sodium tetraborate are dissolved in 1000 ml of THF and 600 ml of water and degassed. 9.3 g (13.3 mmol) of bis(triphenylphosphine)palladium(II) chloride and 1 g (20 mmol) of hydrazinium hydroxide are added. The reaction mixture is subsequently stirred at 70° C. for 48 h under a protective-gas atmosphere. The cooled solution is diluted with toluene, washed a number of times with water, dried and evaporated. The product is purified by column chromatography on silica gel with toluene/heptane (1:2). Yield: 155 g (553 mmol), 83% of theory.

(14) The following compound c1 was prepared analogously:

(15) TABLE-US-00003 Reactant 1 Reactant 2 Product Yield c1 77%

d) 6′-bromo-2′-fluoro-biphenyl-2-ol

(16) ##STR00346##

(17) 112 g (418 mmol) of 6-bromo-2-fluoro-2′-methoxybiphenyl are dissolved in 2 l of dichloromethane and cooled to 5° C. 41.01 ml (431 mmol) of boron tribromide are added dropwise to this solution over the course of 90 min., and stirring is continued overnight. Water is subsequently slowly added to the mixture, and the organic phase is washed three times with water, dried over Na.sub.2SO.sub.4, evaporated in a rotary evaporator and purified by chromatography. Yield: 104 g (397 mmol), 98% of theory.

(18) The following compound d1 was prepared analogously:

(19) TABLE-US-00004 Reactant Product Yield d1 92%

e) 1-Bromo-dibenzofuran

(20) ##STR00349##

(21) 111 g (416 mmol) of 6′-bromo-2′-fluorobiphenyl-2-ol are dissolved in 2 I of SeccoSolv® DMF (max 0.003% of H.sub.2O) and cooled to 5° C. 20 g (449 mmol) of sodium hydride (60% suspension in paraffin oil) are added in portions to this solution, and the mixture is stirred for a further 20 min. after the addition is complete and then heated at 100° C. for 45 min. After cooling, 500 ml of ethanol are slowly added to the mixture, which is then evaporated to dryness in a rotary evaporator and purified by chromatography. Yield: 90 g (367 mmol), 88.5% of theory.

(22) The following compound e1 was prepared analogously:

(23) TABLE-US-00005 Reactant Product Yield e1 0 81%

f) 1-bromo-8-iodo-dibenzofuran

(24) ##STR00352##

(25) 20 g (80 mmol) of dibenzofuran-1-boronic acid, 2.06 g (40.1 mmol) of iodine, 3.13 g (17.8 mmol) of iodic acid, 80 ml of acetic acid, 5 ml of sulfuric acid, 5 ml of water and 2 ml of chloroform are stirred at 65° for 3 hours. After cooling, water is added to the mixture, and the solid which has precipitated out is filtered off with suction and washed three times with water. The residue is recrystallised from toluene and from dichloromethane/heptane. The yield is 25.6 g (68 mmol), corresponding to 85% of theory.

(26) The following compounds were prepared analogously:

(27) TABLE-US-00006 Reactant Product Yield f1 [65642-94-6] 81% f2 84% f3 78%

g) 3-(1-bromo-dibenzothiophene-3-yl)-9-phenyl-9H-carbazole

(28) ##STR00359##

(29) 22 g (66 mmol) of 1,3-dibromodibenzothiophene, 17 g (664 mmol) of 2-N-phenylcarbazole-3-boronic acid and 13.7 g (100 mmol) of sodium tetraborate are dissolved in 100 ml of THF and 60 ml of water and degassed. 0. g (1.3 mmol) of bis(triphenylphosphine)palladium(II) chloride and 1 g (20 mmol) of hydrazinium hydroxide are added. The reaction mixture is subsequently stirred at 70° C. for 48 h under a protective-gas atmosphere. The cooled solution is diluted with toluene, washed a number of times with water, dried and evaporated. The product is purified by column chromatography on silica gel with toluene/heptane (1:2). Yield: 13.2 g (26 mmol), 40% of theory.

(30) The following compounds were prepared analogously:

(31) TABLE-US-00007 Reactant 1 Reactant 2 Product Yield g1 0 [1225467-30-0] [854952-58-2] 27% g2 [1225467-28-6] 24% [854952-58-2] g3 [854952-58-2] 31% [1453088-13-5]

h) dibenzofuran-1-boronic acid

(32) ##STR00369##

(33) 180 g (728 mmol) of 1-bromodibenzofuran are dissolved in 1500 ml of dry THF and cooled to −78° C. 305 ml (764 mmol/2.5 M in hexane) of n-butyllithium are added over the course of about 5 min. at this temperature, and the mixture is subsequently stirred at −78° C. for a further 2.5 h. 151 g (1456 mmol) of trimethyl borate are added as rapidly as possible at this temperature, and the reaction is slowly allowed to come to room temperature (about 18 h). The reaction solution is washed with water, and the solid which has precipitated out and the organic phase are dried azeotropically with toluene. The crude product is washed by stirring with toluene/methylene chloride at about 40° C. and filtered off with suction. Yield: 146 g (690 mmol), 95% of theory.

(34) The following compounds were prepared analogously:

(35) TABLE-US-00008 Reactant Product Yield h1 0 81% h2 73% [65642-94-6] h3 78% h4 81% h5 86% h6 0 83% h7 85% h8 80% h9 83% h10 82% h11 0 81%

j) 2-Dibenzofuran-1-yl-4-phenyl-quinazoline

(36) ##STR00392##

(37) 23 g (110.0 mmol) of dibenzofuran-1-boronic acid, 29.5 g (110.0 mmol) of 2-chloro-4-phenyl-quinazoline and 26 g (210.0 mmol) of sodium carbonate are suspended in 500 ml of ethylene glycol diamine ether and 500 ml of water. 913 mg (3.0 mmol) of tri-o-tolylphosphine and then 112 mg (0.5 mmol) of palladium(II) acetate are added to this suspension, and the reaction mixture is heated under reflux for 16 h. After cooling, the organic phase is separated off, filtered through silica gel, washed three times with 200 ml of water and subsequently evaporated to dryness. The residue is recrystallised from toluene and from dichloromethane/heptane. The yield is 32 g (86 mmol), corresponding to 80% of theory.

(38) The following compounds were prepared analogously:

(39) TABLE-US-00009 Reactant 1 Reactant 2 Product Yield j1 [29874-83-7] 78% j2 [6484-25-9] 70% j3 00 [1292317-90-8] 01 71% j4 02 03 [29874-83-7] 04 77% j5 05 06 [6484-25-9] 07 76% j6 08 09 [29874-83-7] 0 74% j7 [29874-83-7] 75% j8 [6484-25-9] 71% j9 [29874-83-7] 64% j10 0 [29874-83-7] 59% j11 [760212-40-6] 67% j12 71% [30169-34-7]

i) 2-(8-bromo-dibenzofuran-1-yl)-4-phenyl-quinazoline

(40) ##STR00429##

(41) 70.6 g (190.0 mmol) of 2-dibenzofuran-1-yl-4-phenylquinazoline are suspended in 2000 ml of acetic acid (100%) and 2000 ml of sulfuric acid (95-98%). 34 g (190 mmol) of NBS are added in portions to this suspension, and the mixture is stirred in the dark for 2 hours. Water/ice are then added, and the solid is separated off and rinsed with ethanol. The residue is recrystallised from toluene. The yield is 59 g (130 mmol), corresponding to 69% of theory.

(42) In the case of the thiophene derivatives, nitrobenzene is employed instead of sulfuric acid and elemental bromine is employed instead of NBS.

(43) The following compounds were prepared analogously:

(44) TABLE-US-00010 Reactant Product Yield i1 0 70% i2 73% i3 71% i4 62% i5 60% i6 0 65% i7 69%

k) 9-Phenyl-3-[9-(4-phenyl-quinazolin-2-yl)-dibenzofuran-2-yl]-9H-carbazole

(45) ##STR00444##

(46) 70.3 g (156 mmol) of 2-(8-bromodibenzofuran-1-yl)-4-phenylquinazoline, 50 g (172 mmol) of N-phenylcarbazole-3-boronic acid and 36 g (340 mmol) of sodium carbonate are suspended in 1000 ml of ethylene glycol diamine ether and 280 ml of water. 1.8 g (1.5 mmol) of tetrakis(triphenylphosphine)-palladium(0) are added to this suspension, and the reaction mixture is heated under reflux for 16 h. After cooling, the organic phase is separated off, filtered through silica gel, washed three times with 200 ml of water and subsequently evaporated to dryness. The product is purified by column chromatography on silica gel with toluene/heptane (1:2) and finally sublimed in a high vacuum (p=5×10.sup.−7 mbar) (purity 99.9%). The yield is 68 g (112 mmol), corresponding to 72% of theory.

(47) The following compounds were prepared analogously:

(48) TABLE-US-00011 Reactant 1 Reactant 2 Product Yield k1 60% k2 0 65% k4 53% k5 58% k6 52% k7 0 69% k8 67% k9 69% k10 0 55% k11 69% k12 71% k13 0 74% k14 67% k15 65% k16 82% k17 0 51% k18 62% k19 77% k20 00 01 64% k21 02 03 04 72% k22 05 06 07 66% k23 08 09 0 75% k24 78% k25 70% k26 76% k27 0 70% k28 74% k29 73% k30 0 72% k31 69%

l) 8-(9-phenyl-9H-carbazol-3-yl)-dibenzofuran-1-boronic acid

(49) ##STR00535##

(50) 20 g (182 mmol) of 3-(9-bromodibenzofuran-2-yl)-9-phenyl-9H-carbazole are dissolved in 400 ml of dry THF and cooled to −78° C. 77 ml (190 mmol/2.5 M in hexane) of n-butyllithium are added over the course of about 5 min. at this temperature, and the mixture is subsequently stirred at −78° C. for a further 2.5 h. 38 g (365 mmol) of trimethyl borate are added as rapidly as possible at this temperature, and the reaction is slowly allowed to come to RT (about 18 h). The reaction solution is washed with water, and the solid which has precipitated out and the organic phase are dried azeotropically with toluene. The crude product is washed by stirring with toluene/methylene chloride at about 40° C. and filtered off with suction. Yield: 16.7 g (690 mmol), 90% of theory.

(51) The following compounds were prepared analogously:

(52) TABLE-US-00012 Reactant Product Yield l1 81% l2 84% l3 0 78% l4 77% l5 72% l6 77% l7 75% l8 0 70% l9 71%

m) 3-[9-(4-biphenyl-4-yl-quinazolin-2-yl)-dibenzofuran-2-yl]-9-phenyl-9H-carbazole

(53) ##STR00554##

(54) 49.8 g (110.0 mmol) of 8-(9-phenyl-9H-carbazol-3-yl)dibenzofuran-1-boronic acid, 34 g (110.0 mmol) of 4-biphenyl-4-yl-2-chloroquinazoline and 26 g (210.0 mmol) of sodium carbonate are suspended in 500 ml of ethylene glycol diamine ether and 500 ml of water. 913 mg (3.0 mmol) of tri-o-tolylphosphine and then 112 mg (0.5 mmol) of palladium(II) acetate are added to this suspension, and the reaction mixture is heated under reflux for 16 h. After cooling, the organic phase is separated off, filtered through silica gel, washed three times with 200 ml of water and subsequently evaporated to dryness. The product is purified by column chromatography on silica gel with toluene/heptane (1:2) and finally sublimed in a high vacuum (p=5×10.sup.−7 mbar) (purity 99.9%). The yield is 60 g (87 mmol), corresponding to 80% of theory.

(55) The following compounds were prepared analogously:

(56) TABLE-US-00013 Reactant 1 Reactant 2 Product Yield m1 78% m2 0 76% m3 72% m4 69% m5 81% m6 0 88% m7 79% m8 75% m9 0 83% m10 76% m11 71% m12 0 80% m13 75% m14 74% m15 73% m16 00 01 02 69% m17 03 04 05 59% m18 06 07 08 73% m19 09 0 78% m20 70% m21 73% m22 0 67% m23 68% m24 76% m25 79% m26 0 77% m27 78% m30 75% m31 0 76% m32 78% m33 73%

n) 3-(9-benzimidazol-1-yl-dibenzofuran-2-yl)-9-phenyl-9H-carbazole

(57) ##STR00648##

(58) 10 g (84.7 mmol) of benzimidazole, 42 g (127.4 mmol) of CsCO.sub.3, 2.4 g (14.7 mmol) of CuI and 30.7 g (63 mmol) of 3-(9-bromodibenzofuran-2-yl)-9-phenyl-9H-carbazole are suspended in 100 ml of degassed DMF under a protective gas, and the reaction mixture is heated under reflux at 120° C. for 40 h. After cooling, the solvent is removed in vacuo, the residue is dissolved in dichloromethane, and water is added. The organic phase is then separated off and filtered through silica gel. The yield is 28 g (53 mmol), corresponding to 87% of theory.

(59) The following compounds are prepared analogously:

(60) TABLE-US-00014 Reactant 1 Reactant 2 Product Yield n1 0 80% n2 83% n3 79% n4 0 86%

o) 9-phenyl-3-[9-(2-phenyl-benzimidazol-1-yl)-dibenzofuran-2-yl]-9H-carbazole

(61) ##STR00661##

(62) 26 g (50 mmol) of 3-(9-benzimidazol-1-yldibenzofuran-2-yl)-9-phenyl-9H-carbazole, 560 mg (25 mmol) of Pd(OAc).sub.2, 19.3 g (118 mmol) of CuI and 20.8 g (100 mmol) of iodobenzene are suspended in 300 ml of degassed DMF under a protective gas, and the reaction mixture is heated under reflux at 140° C. for 24 h. After cooling, the solvent is removed in vacuo, the residue is dissolved in dichloromethane, and water is added. The organic phase is then separated off and filtered through silica gel. The product is purified by column chromatography on silica gel with toluene/heptane (1:2) and finally sublimed in a high vacuum (p=5×10.sup.−7 mbar) (purity 99.9%). The yield is 17.8 g (30 mmol), corresponding to 60% of theory.

(63) The following compounds were prepared analogously:

(64) TABLE-US-00015 Reactant 1 Reactant 2 Product Yield o1 55% o2 53%  % o3 0 47% o4 44% o5 51%

(65) Fabrication of OLEDs

(66) The following examples V1-V7 and E1-E11 (see Table 1 and 2) show data for various OLEDs.

(67) Substrate pre-treatment of examples V1-7 and E1-E1a: Glass plates with structured ITO (50 nm, indium tin oxide) form the substrates on which the OLEDs are processed. Before evaporation of the OLED materials, the substrates are pre-baked for 15 minutes at 250° C., followed by an O.sub.2 plasma treatment for 130 seconds.

(68) The OLEDs have in principle the following layer structure: substrate/optional hole-injection layer (HIL)/hole-transport layer (HTL)/optional interlayer (IL)/electron-blocking layer (EBL)/emission layer (EML)/optional hole-blocking layer (HBL)/electron-transport layer (ETL)/optional electron-injection layer (EIL) and finally a cathode. The cathode is formed by an aluminium layer with a thickness of 100 nm. The exact layer structure (and layer thickness) is denoted in Table 1. The materials used for the OLED fabrication are presented in Table 3.

(69) All materials are applied by thermal vapour deposition in a vacuum chamber. The emission layer here always consists of at least one matrix material (host material) and an emitting dopant (emitter), which is admixed with the matrix material or matrix materials in a certain proportion by volume by co-evaporation. An expression such as IC1:M1:TEG1 (55%:35%:10%) here means that material IC1 is present in the layer in a proportion by volume of 55%, M1 is present in the layer in a proportion of 35% and TEG1 is present in the layer in a proportion of 10%. Analogously, the electron-transport layer may also consist of a mixture of two materials.

(70) The OLEDs are characterised by standard methods. For this purpose, the electroluminescence spectra, the current efficiency (CE1000, measured in cd/A at 1000 cd/m.sup.2), the luminous efficacy (LE1000, measured in lm/W at 1000 cd/m.sup.2), the external quantum efficiency (EQE1000, measured in % at 1000 cd/m.sup.2) and the voltage (U1000, measured at 1000 cd/m.sup.2 in V) are determined from current/voltage/luminance characteristic lines (IUL characteristic lines) assuming a Lambertian emission profile. The electroluminescence (EL) spectra are recorded at a luminous density of 10.sup.3 (1000) cd/m.sup.2 and the CIE 1931 x and y coordinates are then calculated from the EL spectrum.

(71) For selected experiments, the lifetime is determined. The lifetime is defined as the time after which the luminous density has dropped to a certain proportion from a certain initial luminous density L.sub.1 when the OLED is driven at a constant current. The starting condition L.sub.0; j.sub.0=4000 cd/m.sup.2 and L.sub.1=70% in Table 2 indicates that the in column LT denoted lifetime corresponds to the time in hours (h) needed to fade the OLED from a starting luminous density of 4000 cd/m.sup.2 to 2800 cd/m.sup.2. Accordingly, the lifetime of the starting condition L.sub.0; j.sub.0=20 mA/cm.sup.2, L.sub.1=80% is the time needed to fade the OLED operated at the constant current of 20 mA/cm.sup.2 to 80% of the initial luminous density.

(72) The device data of various OLEDs is summarized in Table 2. The examples V1-V7 are comparison examples according to the state-of-the-art using comparison compounds XXCE1 to XXCE7. The examples E1-E11 show data of inventive OLEDs using inventive examples Inv-1 to Inv-11.

(73) TABLE-US-00016 TABLE 1 OLED structure No. HTL IL EBL EML HBL ETL V1 SpMA1 — — XXCE1:TER4 — ST2:LiQ 140 nm (95%:5%) 40 nm (50%:50%) 35 nm V2 SpA1 HATCN SpMA1 IC1:TEG1 XXCE2 ST2:LiQ  70 nm 5 nm 110 nm (90%:10%) 30 nm 10 nm (50%:50%) 30 nm V3 SpA1 HATCN SpMA1 IC1:TEG1 XXCE3 ST2:LiQ  70 nm 5 nm 110 nm (90%:10%) 30 nm 10 nm (50%:50%) 30 nm V4 SpMA1 — — XXCE4:TER4 — ST2:LiQ 140 nm (95%:5%) 40 nm (50%:50%) 35 nm V5 SpMA1 — — XXCE5:TER4 — ST2:LiQ 140 nm (95%:5%) 40 nm (50%:50%) 35 nm V6 SpMA1 — — XXCE6:TER4 — ST2:LiQ 140 nm (95%:5%) 40 nm (50%:50%) 35 nm V7 SpMA1 — — IC1:TER4 XXCE7 ST2:LiQ 140 nm (95%:5%) 40 nm 10 nm (50%:50%) 25 nm E1 SpMA1 — — Inv-1:TER4 — ST2:LiQ 140 nm (95%:5%) 40 nm (50%:50%) 35 nm E2 SpMA1 — — Inv-2:TER4 — ST2:LiQ 140 nm (95%:5%) 40 nm (50%:50%) 35 nm E3 SpMA1 — — Inv-3:TEG1:TER4 ST2:LiQ 140 nm (80%:15%:5%) 40 nm (50%:50%) 35 nm E4 SpMA1 — — Inv-4:SpMA1:TER4 ST2:LiQ 140 nm (65%:30%:5%) 40 nm (50%:50%) 35 nm E5 SpMA1 — — Inv-5:TEG1:TER4 ST2:LiQ 140 nm (85%:10%:5%) 40 nm (50%:50%) 35 nm E6 SpMA1 — — Inv-6:TER4 — ST2:LiQ 140 nm (97%:3%) 40 nm (50%:50%) 35 nm E7 SpMA1 — — Inv-7:TEG1:TER4 ST2:LiQ 140 nm (85%:10%:5%) 40 nm (50%:50%) 35 nm E8 SpMA1 — — Inv-8:TER4 — ST2:LiQ 140 nm (95%:5%) 40 nm (50%:50%) 35 nm E9 SpA1 HATCN SpMA1 IC1:TEG1 Inv-9 ST2:LiQ  70 nm 5 nm 110 nm (90%:10%) 30 nm 10 nm (50%:50%) 30 nm E10 SpA1 HATCN SpMA1 IC1:TEG1 — Inv-10:LiQ  70 nm 5 nm 110 nm (90%:10%) 30 nm (50%:50%) 30 nm E11 SpMA1 — — Inv-11:TER4 IC1 ST2:LiQ 140 nm (97%:3%) 40 nm 10 nm (50%:50%) 25 nm

(74) TABLE-US-00017 TABLE 2 OLED device data U1000 CE1000 LE1000 EQE CIE x/y at LT Example (V) (cd/A) (lm/W) 1000 10.sup.3 cd/m.sup.2 L.sub.0; j.sub.0 L.sub.1 % (h) V1 4.8 16.1 10.5 14.4% 0.67/0.33 20 mA/cm.sup.2 80 740 V2 3.5 61 55 17.3% 0.33/0.62 20 mA/cm.sup.2 80 120 V3 3.3 63 60 17.5% 0.32/0.63 20 mA/cm.sup.2 80 125 V4 4.7 16.6 11.1 14.7% 0.67/0.33 20 mA/cm.sup.2 80 870 V5 4.5 16.9 11.8 14.9% 0.66/0.34 20 mA/cm.sup.2 80 820 V6 4.8 16.7 10.9 14.6% 0.66/0.34 20 mA/cm.sup.2 80 770 V7 4.8 16.8 11.0 14.7% 0.66/0.33 20 mA/cm.sup.2 80 1010 E1 4.7 16.7 11.2 14.8% 0.67/0.33 20 mA/cm.sup.2 80 1120 E2 4.6 16.8 11.5 14.9% 0.67/0.33 20 mA/cm.sup.2 80 900 E3 4.2 19.6 14.7 17.8% 0.67/0.33 20 mA/cm.sup.2 80 1330 E4 4.4 17.4 12.4 15.6% 0.67/0.33 20 mA/cm.sup.2 80 1170 E5 4.3 19.5 14.2 17.0% 0.66/0.34 20 mA/cm.sup.2 80 1240 E6 4.6 17.0 11.6 15.0% 0.67/0.33 20 mA/cm.sup.2 80 1090 E7 4.3 19.1 14.0 16.9% 0.67/0.33 20 mA/cm.sup.2 80 1140 E8 4.7 16.5 11.0 14.6% 0.67/0.33 20 mA/cm.sup.2 80 1020 E9 3.5 63 57 17.1% 0.33/0.63 20 mA/cm.sup.2 80 135 E10 3.6 64 56 17.2% 0.33/0.63 20 mA/cm.sup.2 80 115 E11 4.6 17.3 11.8 15.1% 0.66/0.34 20 mA/cm.sup.2 80 1100

(75) TABLE-US-00018 TABLE 3 Structures of OLED Materials 0 XXCE1 (comp) XXCE2 (comp) XXCE3 (comp) XXCE4 (comp) XXCE5 (comp) 0 XXCE6 (comp) XXCE7 Inv-1 Inv-2 Inv-3 Inv-4 Inv-5 Inv-6 Inv-7 Inv-8 00 Inv-9 01 Inv-10 02 Inv-11

(76) As can been seen in Table 2, OLEDs containing the compounds of the invention provide improved performance, without regard to whether it is located in the light-emitting layer as a host (i.e. E1-E8), in a hole-blocking layer (i.e. E9) or in an electron-transporting layer (i.e. E10). For example, inventive OLEDs E1, E2, E6 and E8, using inventive compounds as a host for a red phosphorescent emitter, are the same as comparative OLEDs V1 and V4-6 but have improved lifetime. In particular, comparison compound XXCE4 (V4), which has a diazine heterocycle in the 2-position, has a LT of 870 h. However, E1, which is identical to V4 except for using the inventive compound Inv-1, which is identical for XXCE4 except that the diazine is located in the 1-position, has a LT of 1120 h, for an improvement of 29%. Likewise, E9, where an inventive compound is used as a host for a green phosphorescent emitter, shows better lifetime than V2 and V3. Even better results are seen when an inventive compound is used in more than one layer (i.e. E11) is compared to a comparative (i.e. V7) without the inventive compound.