Materials for organic electroluminescence devices

Abstract

The invention relates to pyrimidine derivatives according to formula (I), ##STR00001##
and to organic electroluminescent devices comprising said pyrimidine derivatives as electron transport material.

Claims

1. A compound of formula (1), ##STR00156## wherein: Pym is selected from the group consisting of formula (2) and formula (3), ##STR00157## wherein the dashed bond indicates the bond to the anthracene; Ar is selected from one group of formulae (9) to (25) ##STR00158## ##STR00159## ##STR00160## ##STR00161## wherein the dashed bond is the position of the link to the anthracene of the compound of formula (1); R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, R.sup.9, R.sup.10, R.sup.11, and R.sup.12 are, identically or differently on each occurrence, H, D, F, Cl, Br, I, CHO, N(R.sup.13).sub.2, N(Ar.sup.1).sub.2, B(Ar.sup.1).sub.2, Si(R.sup.13).sub.2, Si(Ar.sup.1).sub.2, C(═O)Ar.sup.1, P(═O)(Ar.sup.1).sub.2, S(═O)Ar.sup.1, S(═O).sub.2Ar.sup.1, CR.sup.13═CR.sup.13Ar.sup.1, CN, NO.sub.2, Si(R.sup.13).sub.3, B(OR.sup.13).sub.2, B(R.sup.3).sub.2, B(N(R.sup.3).sub.2).sub.2, OSO.sub.2R.sup.13, a straight-chain alkyl, alkenyl, alkynyl, alkoxy or thioalkoxy group having 1 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 is optionally substituted by one or more radicals R.sup.13, wherein one or more non-adjacent CH.sub.2 groups are optionally replaced by R.sup.13C═CR.sup.13, C≡C, Si(R.sup.13).sub.2, Ge(R.sup.13).sub.2, Sn(R.sup.13).sub.2, C═O, C═S, C═Se, C═NR.sup.13, P(═O)(R.sup.3), SO, SO.sub.2, NR.sup.13, O, S, or CONR.sup.13, and wherein one or more H atoms are optionally replaced by D, F, Cl, Br, I, CN, NO.sub.2, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms optionally substituted by one or more radicals R.sup.13, an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms optionally substituted by one or more radicals R.sup.13, or a combination of these systems; Ar.sup.1 is, identically or differently on each occurrence, an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms optionally substituted by one or more radicals R.sup.13; wherein two radicals Ar.sup.1 bonded to the same nitrogen, phosphorus, silicon or boron atom are optionally linked to one another by a single bond or a bridge selected from the group consisting of B(R.sup.13), C(R.sup.13).sub.2, Si(R.sup.13).sub.2, C═O, C═NR.sup.13, C═C(R.sup.13).sub.2, O, S, S═O, SO.sub.2, N(R.sup.13), P(R.sup.13), and P(═O)R.sup.13; and R.sup.13 is, identically or differently on each occurrence, H, D, or an aliphatic, aromatic, and/or heteroaromatic hydrocarbon radical having 1 to 20 C atoms, wherein one or more H atoms are optionally replaced by D or F; and wherein two or more adjacent substituents R.sup.13 optionally define a mono- or polycyclic, aliphatic or aromatic ring system.

2. The compound of claim 1, wherein said compound is selected from the group consisting of formulae (4), (5), and (6): ##STR00162##

3. The compound of claim 2, wherein said compound is selected from the group consisting of formulae (4a), (5a), and (6a): ##STR00163##

4. The compound of claim 1, wherein Ar is selected from the group consisting of formulae (9a), (10a), (12a), (14a), and (16a) ##STR00164## ##STR00165##

5. The compound of claim 1, wherein the radicals R.sup.1 to R.sup.12 are, identically or differently on each occurrence, selected from the group consisting of H, D, F, N(Ar.sup.1).sub.2, C(═O)Ar.sup.1, P(═O)(Ar.sup.1).sub.2, S(═O)Ar.sup.1, S(═O).sub.2Ar.sup.1, CN, Si(R.sup.13).sub.3, a straight-chain alkyl group having 1 to 10 C atoms, and a branched or cyclic alkyl group having 3 to 10 C atoms, each of which is optionally substituted by one or more radicals R.sup.13, wherein one or more non-adjacent CH.sub.2 groups are optionally replaced by R.sup.13C═CR.sup.13, and wherein one or more H atoms are optionally replaced by D, F, or an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms optionally substituted by one or more radicals R.sup.13.

6. The compound of claim 1, wherein the radicals R.sup.9, R.sup.10 and R.sup.11 are, identically or differently on each occurrence, H or an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms optionally substituted by one or more radicals R.sup.13.

7. An electronic device comprising at least one compound of claim 1.

8. The electronic device of claim 7, wherein said electronic 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, organic dye-sensitised solar cells, organic optical detectors, organic photoreceptors, organic field-quench devices, light-emitting electrochemical cells, organic laser diodes, and organic plasmon emitting devices.

9. The electronic device of claim 8, wherein said compound is employed in an electron-transport layer, and/or in an electron-injection layer, and/or in a hole-blocking layer, and/or as matrix material for fluorescent emitters in an emitting layer.

10. The electronic device of claim 9, wherein said compound is employed in an electron-transport layer or in an electron-injection layer in a mixture with a further electron-transport or electron-injection material.

11. A mixture comprising at least one compound of claim 1 and at least one organic alkali-metal compound.

12. A formulation comprising at least one compound of claim 1 and at least one solvent.

13. The compound of claim 1, wherein Ar is selected from one of formulae (12) to (19).

14. A process for preparing the compound of claim 1, comprising reacting an anthracene derivative substituted by a boronic acid group or a boronic acid ester group with a pyrimidine derivative substituted by a reactive leaving group.

15. The electronic device of claim 7, wherein said electronic device is an electroluminescent device.

16. The electronic device of claim 10, wherein said further electron-transport or electron-injection material comprises an organic alkali-metal compound.

17. A compound of formula (4a), formula (5a), or formula (6a), ##STR00166## wherein the dashed bond indicates the bond to the anthracene; Ar is selected from one group of formulae (9) to (25) ##STR00167## ##STR00168## ##STR00169## ##STR00170## wherein the dashed bond is the position of the link to the anthracene of the compound of formula (1); R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, R.sup.9, R.sup.10, R.sup.11, and R.sup.12 are, identically or differently on each occurrence, H, D, F, N(Ar.sup.1).sub.2, C(═O)Ar.sup.1, P(═O)(Ar.sup.1).sub.2, S(═O)Ar.sup.1, S(═O).sub.2Ar.sup.1, CN, Si(R.sup.13).sub.3, a straight-chain alkyl group having 1 to 10 C atoms, and a branched or cyclic alkyl group having 3 to 10 C atoms, each of which is optionally substituted by one or more radicals R.sup.13, wherein one or more non-adjacent CH.sub.2 groups are optionally replaced by R.sup.13C═CR.sup.13, and wherein one or more H atoms are optionally replaced by D, F or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms optionally substituted by one or more radicals R.sup.13, an aryloxy or heteroaryloxy group having 5 to 30 aromatic ring atoms optionally substituted by one or more radicals R.sup.13; Ar.sup.1 is, identically or differently on each occurrence, an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms optionally substituted by one or more radicals R.sup.13; wherein two radicals Ar.sup.1 bonded to the same nitrogen, phosphorus, silicon or boron atom are optionally linked to one another by a single bond or a bridge selected from the group consisting of B(R.sup.13), C(R.sup.13).sub.2, Si(R.sup.13).sub.2, C═O, C═NR.sup.13, C═C(R.sup.13).sub.2, O, S, S═O, SO.sub.2, N(R.sup.13), P(R.sup.13), and P(═O)R.sup.13; and R.sup.13 is, identically or differently on each occurrence, 1H, D, or an aliphatic, aromatic, and/or heteroaromatic hydrocarbon radical having 1 to 20 C atoms, wherein one or more H atoms are optionally replaced by D or F; and wherein two or more adjacent substituents R.sup.13 optionally define a mono- or polycyclic, aliphatic or aromatic ring system.

18. The compound of claim 17, wherein the radicals R.sup.9, R.sup.10 and R.sup.11 are, identically or differently on each occurrence, H or an aromatic or heteroaromatic ring system having 5 to 24 aromatic ring atoms optionally substituted by one or more radicals R.sup.13.

19. An electronic device comprising at least one compound of claim 18, wherein said electronic 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, organic dye-sensitised solar cells, organic optical detectors, organic photoreceptors, organic field-quench devices, light-emitting electrochemical cells, organic laser diodes, and organic plasmon emitting devices, and wherein said at least one compound is included in an electron-transport layer, an electron-injection layer, in a hole-blocking layer, and/or as a matrix material for fluorescent emitters in an emitting layer.

20. The electronic device of claim 19, wherein the at least one compound is present in an electron-transport layer or in an electron-injection layer with a another electron-transport or electron-injection material, and the electronic device is an organo electroluminescent device.

21. The compound of claim 17, wherein Ar is selected from the group consisting of formulae (9a), (10a), (12a), (14a), and (16a) ##STR00171## ##STR00172##

22. A compound of formula (1) ##STR00173## wherein: Pym is selected from the group consisting of formula (2) and formula (3), ##STR00174## wherein the dashed bond indicates the bond to the anthracene; Ar is selected from the group consisting of formulae (9a), (10a), and (16a) ##STR00175## wherein the dashed bond is the position of the link to the anthracene of the compound of formula (1); R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, R.sup.9, R.sup.10, R.sup.11, and R.sup.12 are, identically or differently on each occurrence, H, D, F, Cl, Br, I, CHO, N(R.sup.13).sub.2, N(Ar.sup.1).sub.2, B(Ar.sup.1).sub.2, Si(R.sup.13).sub.2, Si(Ar.sup.1).sub.2, C(═O)Ar.sup.1, P(═O)(Ar.sup.1).sub.2, S(═O)Ar.sup.1, S(═O).sub.2Ar.sup.1, CR.sup.13═CR.sup.13Ar.sup.1, CN, NO.sub.2, Si(R.sup.13).sub.3, B(OR.sup.13).sub.2, B(R.sup.13).sub.2, B(N(R.sup.13).sub.2).sub.2, OSO.sub.2R.sup.13, a straight-chain alkyl, alkenyl, alkynyl, alkoxy or thioalkoxy group having 1 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 is optionally substituted by one or more radicals R.sup.13, wherein one or more non-adjacent CH.sub.2 groups are optionally replaced by R.sup.13C═CR.sup.13, C≡C, Si(R.sup.13).sub.2, Ge(R.sup.13).sub.2, Sn(R.sup.13).sub.2, C═O, C═S, C═Se, C═NR.sup.13, P(═O)(R.sup.13), SO, SO.sub.2, NR.sup.13, O, S, or CONR.sup.13, and wherein one or more H atoms are optionally replaced by D, F, Cl, Br, I, CN, NO.sub.2, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms optionally substituted by one or more radicals R.sup.13, an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms optionally substituted by one or more radicals R.sup.13, or a combination of these systems; and wherein two or more adjacent substituents R.sup.1 to R.sup.12 optionally define a mono- or polycyclic, aliphatic or aromatic ring system; Ar.sup.1 is, identically or differently on each occurrence, an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms optionally substituted by one or more radicals R.sup.13; wherein two radicals Ar.sup.1 bonded to the same nitrogen, phosphorus, silicon or boron atom are optionally linked to one another by a single bond or a bridge selected from the group consisting of B(R.sup.13), C(R.sup.13).sub.2, Si(R.sup.13).sub.2, C═O, C═NR.sup.13, C═C(R.sup.13).sub.2, O, S, S═O, SO.sub.2, N(R.sup.13), P(R.sup.13), and P(═O)R.sup.13; and R.sup.13 is, identically or differently on each occurrence, H, D, or an aliphatic, aromatic, and/or heteroaromatic hydrocarbon radical having 1 to 20 C atoms, wherein one or more H atoms are optionally replaced by D or F; and wherein two or more adjacent substituents R.sup.13 optionally define a mono- or polycyclic, aliphatic or aromatic ring system.

Description

EXAMPLES

Example 1: Synthesis of 5-(10-benzo[a]anthracen-4-ylanthracen-9-yl)-pyrimidine

a) 4-Anthracen-9-ylbenzo[a]anthracene

(1) ##STR00133##

(2) 49.7 g (184 mmol) of 9-bromoanthracene, 50 g (184 mmol) of 2-benzo[a]-anthraceneboronic acid and 88.9 g (386 mmol) of K.sub.3PO.sub.4 are suspended in 900 ml of toluene, 180 ml of 1,4-dioxane and 1100 ml of water. 0.42 g (2 mmol) of Pd(OAc).sub.2 and 11 ml of a 1 M tri-tert-butylphosphine solution are added to this suspension. The reaction mixture is heated under reflux for 16 h. After cooling, the reaction mixture is filtered through silica gel, and the organic phase is separated off, washed three times with 200 ml of water and subsequently evaporated to dryness. The residue is recrystallised from toluene. Yield 48 g, 65% of theory.

b) 4-(10-Bromoanthracen-9-yl)benzo[a]anthracene

(3) ##STR00134##

(4) 30.9 g (76.4 mmol) of 4-anthracen-9-ylbenzo[a]anthracene are initially introduced in 500 ml of chloroform, and 1.2 g (7.6 mmol) of iron(III) chloride are added. A solution of 15.6 g (87.86 mmol) of NBS in 20 ml of chloroform is subsequently added dropwise at 0° C. with exclusion of light, and the mixture is stirred at this temperature for a further 2 h. 150 ml of water are subsequently added to the mixture, which is then extracted with ethyl acetate. The organic phase is dried over MgSO.sub.4, and the solvents are removed in vacuo. The product is recrystallised from toluene. Yield: 20.4 g, 55% of theory, purity according to HPLC about 98%.

c) 5-(10-Benzo[a]anthracen-4-ylanthracen-9-yl)pyrimidine

(5) ##STR00135##

(6) 5-Pyrimidineboronic acid is prepared analogously to Org. Biomol. Chem., 2004, 2, 852. 20 g (41.4 mmol) of 10-(bromoanthracen-9-yl)benzo[a]-anthracene and 7.2 g (57.9 mmol) of 5-pyrimidineboronic acid are suspended in 600 ml of ethylene glycol dimethyl ether and 150 ml of EtOH. 200 ml of a 0.5 M Na.sub.2CO.sub.3 solution are added to the reaction mixture. 500 mg (0.414 mmol) of Pd(PPh.sub.3).sub.4 are added to this suspension, and the mixture is heated under reflux for 12 h. After cooling, the precipitated solid is filtered off with suction, washed with water and ethanol and dried. The residue is extracted with hot toluene, recrystallised from toluene and finally sublimed in a high vacuum. The purity is 99.9%. Yield: 10 g, 50% of theory.

Example 2: Synthesis of 2-(10-benzo[a]anthracen-4-ylanthracen-9-yl)-5-phenylpyrimidine

a) 2-Anthracen-9-yl-5-phenylpyrimidine

(7) ##STR00136##

(8) 36.1 g (140.4 mmol) of 9-bromoanthracene are dissolved in 600 ml of dry THF and cooled to −78° C. At this temperature, 66.4 ml (165.9 mmol/2.5 M in hexane) of n-butyllithium are added over the course of about 20 min., and the mixture is subsequently stirred at −78° C. for a further 2.5 h. 45.1 ml (191.4 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).

(9) 30 g (127.6 mmol) of 2-bromo-5-phenylpyrimidine are dissolved in a degassed mixture of 800 ml of toluene and 68 ml of tetraethylammonium hydroxide, and 4.4 g (3.83 mmol) of Pd(PPh.sub.3).sub.4 are added. The 9-boronoanthracene solution is added dropwise thereto. The reaction mixture is heated under reflux for 8 h. After cooling, dichloromethane is added, the water phase is separated off, and the organic phase is concentrated by azeotropic distillation with toluene. The reaction product is recrystallised from toluene, giving 35 g (82%) of 2-anthracen-9-yl-5-phenylpyrimidine.

b) 2-(10-Bromoanthracen-9-yl)-5-phenylpyrimidine

(10) ##STR00137##

(11) 35 g (105.3 mmol) of 2-anthracen-9-yl-5-phenylpyrimidine are initially introduced in 500 ml of chloroform. A solution of 20.7 g (115.8 mmol) of NBS in 500 ml of chloroform is subsequently added dropwise at 0° C. with exclusion of light, and the mixture is stirred at this temperature for a further 4 h. 150 ml of water are subsequently added to the mixture, which is then extracted with ethyl acetate. The organic phase is dried over MgSO.sub.4, and the solvents are removed in vacuo. The product is recrystallised from toluene. Yield: 32.5 g, 75% of theory, purity according to HPLC about 98%.

c) 2-(10-Benzo[a]anthracen-4-ylanthracen-9-yl)-5-phenylpyrimidine

(12) ##STR00138##

(13) 30 g (72.94 mmol) of 2-(10-bromoanthracen-9-yl)-5-phenylpyrimidine, 21.8 g (80.24 mmol) of 2-benzo[a]anthraceneboronic acid and 32 g (153 mmol) of K.sub.3PO.sub.4 are suspended in 600 ml of toluene, 150 ml of 1,4-dioxane and 150 ml of water. 2.1 g (1.82 mmol) of Pd(PPh.sub.3).sub.4 are added to this suspension. The reaction mixture is heated under reflux for 16 h. After cooling, dichloromethane is added to the reaction mixture, the water phase is separated off, and the organic phase is concentrated by azeotropic distillation with toluene and subsequently evaporated to dryness. The residue is recrystallised from toluene and finally sublimed in a high vacuum. The purity is 99.9%. Yield: 20 g, 50% of theory.

Example 3: Synthesis of 5-(10-phenanthren-3-ylanthracen-9-yl)-2-pyridin-2-ylpyrimidine

a) 5-Bromo-2-pyridin-2-ylpyrimidine

(14) ##STR00139##

(15) 14.6 ml (150 mmol) of 2-bromopyridine are dissolved in 700 ml of dry THF and cooled to −78° C. At this temperature, 66.0 ml (165 mmol/2.5 M in hexane) of n-BuLi are added over the course of about 20 min., and the mixture is subsequently stirred at −78° C. for a further 2.5 h. 44.8 ml (165 mmol) of tributyltin chloride are added as rapidly as possible at this temperature, and the reaction is slowly allowed to come to room temperature (about 18 h). 150 ml of NH.sub.4Cl solution are subsequently added to the reaction mixture, which is then extracted with ethyl acetate. The organic phase is dried over MgSO.sub.4, and the solvents are removed in vacuo. Yield: 44 g of 2-(tributyltin)pyridine, 80% of theory.

(16) 30 g (108.6 mmol) of 2-(tributyltin)pyridine are suspended in 600 ml of xylene, and 31 g (108.6 mmol) of 2-iodo-5-bromopyrimidine are added. 3.8 g (5.43 mmol) of Pd(PPh.sub.3).sub.2Cl.sub.2 and 2.85 g (10.86 mmol) of triphenyl-phosphine are added to this suspension. The reaction mixture is heated under reflux for 16 h. After cooling, dichloromethane is added to the reaction mixture, the water phase is separated off, and the organic phase is concentrated by azeotropic distillation with toluene and subsequently evaporated to dryness. The residue is recrystallised from toluene. Yield: 20 g, 78% of theory.

b) 5-Anthracen-9-yl-2-pyridin-2-ylpyrimidine

(17) ##STR00140##

(18) 20.6 g (80 mmol) of 9-bromoanthracene are dissolved in 400 ml of dry THF and cooled to −78° C. At this temperature, 36.8 ml (92 mmol/2.5 M in hexane) of n-BuLi are added over the course of about 20 min., and the mixture is subsequently stirred at −78° C. for a further 2.5 h. 26.4 ml (112 mmol) of triisopropyl borate are added as rapidly as possible t this temperature, and the reaction is slowly allowed to come to room temperature (about 18 h).

(19) 18.9 g (80 mmol) of 5-bromo-2-pyridin-2-ylpyrimidine are dissolved in a degassed mixture of 400 ml of toluene and 42 ml of tetraethylammonium hydroxide (20%), and 2.77 g (2.4 mmol) of Pd(PPh.sub.3).sub.4 are added. The 9-boronoanthracene solution is added dropwise thereto. The reaction mixture is heated under reflux for 8 h. After cooling, dichloromethane is added, the water phase is separated off, and the organic phase is concentrated by azeotropic distillation with toluene. The reaction product is recrystallised from toluene, giving 23 g (85%) of 5-anthracen-9-yl-2-pyridin-2-ylpyrimidine.

c) 5-(10-Bromoanthracen-9-yl)-2-pyridin-2-ylpyrimidine

(20) ##STR00141##

(21) 20 g (68 mmol) of 5-anthracen-9-yl-2-pyridin-2-ylpyrimidine are initially introduced in 300 ml of chloroform. A solution of 13.31 g (74.8 mmol) of NBS in 200 ml of chloroform is subsequently added dropwise at 0° C. with exclusion of light, and the mixture is stirred at this temperature for a further 4 h. 150 ml of water are subsequently added to the mixture, which is then extracted with ethyl acetate. The organic phase is dried over MgSO.sub.4, and the solvents are removed in vacuo. The product is recrystallised from toluene. Yield: 22.4 g, 80% of theory, purity according to HPLC about 98%.

d) 5-(10-Phenanthren-3-ylanthracen-9-yl)-2-pyridin-2-ylpyrimidine

(22) ##STR00142##

(23) 20 g (77.8 mmol) of 3-bromophenanthrene are dissolved in 400 ml of dry THF and cooled to −78° C. At this temperature, 40.5 ml (101.1 mmol/2.5 M in hexane) of n-BuLi are added over the course of about 20 min., and the mixture is subsequently stirred at −78° C. for a further 2.5 h. 28.7 ml (124.4 mmol) of triisopropyl borate are added as rapidly as possible at this temperature, and the reaction is slowly allowed to come to room temperature (about 18 h). 100 ml of NH.sub.4Cl solution are subsequently added to the reaction mixture, which is then extracted with ethyl acetate. The organic phase is dried over MgSO.sub.4, and the solvents are removed in vacuo. Yield: 14 g of 3-phenanthreneboronic acid, 80% of theory.

(24) 22 g (53.36 mmol) of 5-(10-bromoanthracen-9-yl)-2-pyridin-2-ylpyrimidine, 13 g (58.7 mmol) of 3-phenanthreneboronic acid and 23.8 g (112 mmol) of K.sub.3PO.sub.4 are suspended in 200 ml of toluene, 200 ml of 1,4-dioxane and 120 ml of water. 1.85 g (1.6 mmol) of Pd(PPh.sub.3).sub.4 are added to this suspension. The reaction mixture is heated under reflux for 16 h. After cooling, dichloromethane is added to the reaction mixture, the water phase is separated off, and the organic phase is concentrated by azeotropic distillation with toluene and subsequently evaporated to dryness. The residue is recrystallised from toluene and finally sublimed in a high vacuum. The purity is 99.9%. Yield: 16 g, 60% of theory.

Example 4: Production of OLEDs

(25) OLEDs according to the invention and OLEDs in accordance with the prior art are produced by a general process in accordance with WO 2004/058911, which is adapted to the circumstances described here (layer-thickness variation, materials used).

(26) The results for various OLEDs are presented in OLED Examples 1-23 below (see Tables 1 and 2). Glass plates coated with structured ITO (indium tin oxide) in a thickness of 50 nm form the substrates to which the OLEDs are applied. The OLEDs basically have the following layer structure: substrate ITO/hole-transport layer (HTL, 140 nm)/interlayer (IL, 5 nm)/electron-blocking layer (EBL, 20 nm)/emission layer (EML (H1+x % of D1), z nm)/electron-transport layer (ETL, y nm)/optional electron-injection layer (EIL, x nm) and finally a cathode. The cathode is formed by an aluminium layer with a thickness of 100 nm. The precise structure of the OLEDs is shown in Table 1. The materials used for the production of the OLEDs are shown in Table 3.

(27) 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 materials in a certain proportion by volume by coevaporation. An expression such as H1:D1 (95%:5%) here means that material H1 is present in the layer in a proportion by volume of 95% and D1 is present in the layer in a proportion by volume of 5%. Analogously, the electron-transport layer may also consist of a mixture of two materials.

(28) The OLEDs are characterised by standard methods. For this purpose, the electroluminescence spectra, current-voltage-luminance characteristic lines (IUL characteristic lines) and the lifetime are measured. The lifetime is defined as the time after which the luminous density has dropped to a certain proportion from a certain initial luminous density I.sub.0. The expression LD50 means that the said lifetime is the time by which the luminous density has dropped to 0.5.Math.I.sub.0 (to 50%), from 6000 cd/m.sup.2 to 3000 cd/m.sup.2 in the examples for blue (y<0.25) and from 4000 cd/m.sup.2 to 2000 cd/m.sup.2 in the other examples. The current efficiency (cd/A) and the power efficiency (lm/W) are calculated from the IUL characteristic lines.

(29) The compounds according to the invention can be employed, inter alia, as electron-transport material in an electron-transport layer (ETL) for fluorescent and phosphorescent OLEDs. Compounds ETL2, ETL3 and ETL4 according to the invention are used here. Compounds ETL1 and ETL5 are used as comparison in accordance with the prior art. The results for the OLEDs are summarized in Table 2. Examples 1-5 and 21-23 show OLEDs comprising materials in accordance with the prior art and serve as comparative examples. The OLEDs according to Examples 6-20 according to the invention exhibit the advantages on use of compounds of the formula (1) according to the invention.

(30) The use of compounds according to the invention enables, compared with the prior art, improvements to be achieved in the operating voltage, the efficiency and the lifetime of the components.

(31) Compared with the reference components, the electrical characteristic data are better in all cases. With an otherwise identical layer structure, the components according to the invention exhibit improved performance data.

(32) TABLE-US-00003 TABLE 1 Structure of the OLEDs Ex. EML ETL EIL  1 H1:D1 ETL1 EIL1 (comp.) (95%:5%)  20 nm 3 nm 30 nm  2 H1:D1 ETL1:EIL1 — (comp.) (95%:5%)  (50%:50%) 30 nm 20 nm  3 H2:D2 ETL1 EIL2 (comp.) (85%:15%) 30 nm 1 nm 40 nm  4 H2:D2 ETL1 EIL1 (comp.) (85%:15%) 30 nm 3 nm 40 nm  5 H2:D2 ETL1:EIL1 — (comp.) (85%:15%) (50%:50%) 40 nm 30 nm  6 H1:D1 ETL2 EIL1 (95%:5%)  20 nm 3 nm 30 nm  7 H1:D1 ETL3 EIL1 (95%:5%)  20 nm 3 nm 30 nm  8 H1:D1 ETL4 EIL1 (95%:5%)  20 nm 3 nm 30 nm  9 H1:D1 ETL2:EIL1 (95%:5%)  (50%:50%) 30 nm 20 nm 10 H1:D1 ETL3:EIL1 (95%:5%)  (50%:50%) 30 nm 20 nm 11 H1:D1 ETL4:EIL1 (95%:5%)  (50%:50%) 30 nm 20 nm 12 H1:D1 ETL2:EIL1 (95%:5%)  (30%:70%) 30 nm 20 nm 13 H2:D2 ETL2 EIL2 (85%:15%) 20 nm 1 nm 40 nm 14 H2:D2 ETL3 EIL2 (85%:15%) 20 nm 1 nm 40 nm 15 H2:D2 ETL4 EIL2 (85%:15%) 20 nm 1 nm 40 nm 16 H2:D2 ETL2:EIL1 (85%:15%) (50:50) 40 nm 20 nm 17 H2:D2 ETL3:EIL1 (85%:15%) (50%:50%) 40 nm 20 nm 18 H2:D2 ETL4:EIL1 (85%:15%) (50%:50%) 40 nm 20 nm 19 H2:D2 ETL2 EIL1 (85%:15%) 20 nm 3 nm 40 nm 20 H2:D2 ETL4 EIL1 (85%:15%) 20 nm 3 nm 40 nm 21 H2:D2 ETL5:EIL1 — (comp.) (85%:15%) (50%:50%) 40 nm 30 nm 22 H2:D2 ETL5 EIL2 (comp.) (85%:15%) 30 nm 1 nm 40 nm 23 H2:D2 ETL5 EIL1 (comp.) (85%:15%) 30 nm 3 nm 40 nm

(33) TABLE-US-00004 TABLE 2 Results for the OLEDs Voltage [V] Efficiency LD50 for [cd/A] at CIE x/y at I = 6000 Ex. 1000 cd/m.sup.2 1000 cd/m.sup.2 1000 cd/m.sup.2 cd/m.sup.2  1 4.9 6.6 0.14 0.15 250 (comp.)  6 4.3 7.0 0.14 0.14 290  7 4.6 6.9 0.14 0.15 270  8 4.4 7.2 0.14 0.14 310  2 5.1 6.9 0.14 0.15 300 (comp.)  9 4.4 8.4 0.14 0.14 330 10 4.8 8.3 0.14 0.15 320 11 4.6 8.1 0.14 0.14 370 12 4.6 7.9 0.14 0.14 350  3 3.7 46.3 0.33 0.62 900 (comp.) 22 3.9 43.4 0.33 0.61 800 (comp.) 13 3.4 49.1 0.33 0.62 1900 14 3.6 48.5 0.33 0.62 1700 15 3.5 48.7 0.33 0.62 2100  4 4.1 43.3 0.33 0.62 1070 (comp.) 23 4.3 41.2 0.33 0.61 950 (comp.) 19 3.9 45.1 0.33 0.62 1450 20 3.5 50.3 0.33 0.62 1600  5 3.6 44.5 0.33 0.62 1100 (comp.) 21 3.8 41.3 0.33 0.62 900 (comp.) 16 3.4 49.2 0.33 0.62 2100 17 3.5 47.2 0.33 0.62 1700 18 3.3 53.7 0.33 0.62 3100

(34) TABLE-US-00005 TABLE 3 Structural formulae of the materials used   IL   HTL   EBL   ETL1 (comparison)   EIL1   H1   D1 0   H2   D2   ETL2   ETL3   ETL4   ETL5 (comparison) LiF is used as EIL2.