MATERIALS FOR ORGANIC ELECTROLUMINESCENT DEVICES

Abstract

The present invention relates to organic electroluminescent devices comprising a sterically hindered fluorescent perylene emitter compound and a sensitizer compound and to sterically hindered fluorescent perylene emitter compounds.

Claims

1. Electronic device comprising anode, cathode and at least one organic layer comprising a sterically hindered fluorescent perylene emitter compound, characterised in that the fluorescent perylene emitter compound is represented by the general following formula (I) and in that the organic layer or a layer adjacent to the organic layer on the anode or cathode side comprises a sensitizer compound selected from a compound that exhibits delayed fluorescence or a phosphorescent compound, ##STR00191## wherein R.sup.1 to R.sup.12 are each selected, identically or differently, from H, a straight-chain alkyl or alkoxy group having 3 to 20 carbon atoms, a branched or cyclic alkyl or alkoxy group having 3 to 20 carbon atoms, an alkenyl or alkynyl group having 3 to 20 carbon atoms, an aralkyl group, preferably having 7 to 60 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.20 and where one or more CH.sub.2 groups in the above-mentioned groups may be replaced by Si(R.sup.20).sub.2, Ge(R.sup.20).sub.2, Sn(R.sup.20).sub.2, C═O, C═S, C═Se, C═NR.sup.20, P(═O)(R.sup.20), SO, SO.sub.2, NR.sup.20, —O—, —S—, —COO— or —CONR.sup.20— and where one or more H atoms in the above-mentioned groups may be replaced by D, F, Cl, Br, I, CN or NO.sub.2, or an aromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.20; R.sup.20 is on each occurrence, identically or differently, selected from H, D, F, or a straight-chain alkyl group having 1 to 40 carbon atoms, or a branched or cyclic alkyl group having 3 to 40 carbon atoms, or an alkenyl or alkynyl group having 2 to 40 carbon atoms, or an aralkyl group having 7 to 40 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.21 or an aromatic ring system having 5 to 40 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.21, where two or more radicals R.sup.20 may be joined to form an aromatic ring system or a (poly)cyclic alkyl group, which may in each case be substituted by one or more radicals R.sup.21; R.sup.21 is on each occurrence, identically or differently, selected from H, D, F, or a straight-chain alkyl group having 1 to 20 carbon atoms, or a branched or cyclic alkyl group having 3 to 20 carbon atoms, or an alkenyl or alkynyl group having 2 to 20 carbon atoms, or an aromatic ring system having 5 to 30 aromatic ring atoms, where two or more radicals R.sup.21 may be joined to form an aromatic ring system or a (poly)cyclic alkyl group; with the proviso that at least two, preferably three, more preferably four, of radicals R.sup.1 to R.sup.12, which are not located at the same benzene ring of the perylene basic skeleton, are other than H.

2. Electronic device according to claim 1, characterized in that the compound of formula (I) represents a compound of general formula (II) ##STR00192## wherein R.sup.2, R.sup.5, R.sup.8, R.sup.11 are each selected, identically or differently, from a straight-chain alkyl or alkoxy group having 3 to 20 carbon atoms, a branched or cyclic alkyl or alkoxy group having 3 to 20 carbon atoms, an alkenyl or alkynyl group having 3 to 20 carbon atoms, an aralkyl group, preferably having 7 to 60 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.20 and where one or more CH.sub.2 groups in the above-mentioned groups may be replaced by Si(R.sup.20).sub.2, Ge(R.sup.20).sub.2, Sn(R.sup.20).sub.2, C═O, C═S, C═Se, C═NR.sup.20, P(═O)(R.sup.20), SO, SO.sub.2, NR.sup.20, —O—, —S—, —COO— or —CONR.sup.20— and where one or more H atoms in the above-mentioned groups may be replaced by D, F, Cl, Br, I, CN or NO.sub.2, or an aromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.20; R.sup.20 is on each occurrence, identically or differently, selected from H, D, F, or a straight-chain alkyl group having 1 to 40 carbon atoms, or a branched or cyclic alkyl group having 3 to 40 carbon atoms, or an alkenyl or alkynyl group having 2 to 40 carbon atoms, or an aralkyl group having 7 to 40 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.21, or an aromatic ring system having 5 to 40 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.21, where two or more radicals R.sup.20 may be joined to form an aromatic ring system or a (poly)cyclic alkyl group, which may in each case be substituted by one or more radicals R.sup.21; R.sup.21 is on each occurrence, identically or differently, selected from H, D, F, or a straight-chain alkyl group having 1 to 20 carbon atoms, or a branched or cyclic alkyl group having 3 to 20 carbon atoms, or an alkenyl or alkynyl group having 2 to 20 carbon atoms, or an aromatic ring system having 5 to 40 aromatic ring atoms, where two or more radicals R.sup.21 may be joined to form an aromatic ring system or a (poly)cyclic alkyl group.

3. Electronic device according to claim 1 or 2, characterized in that R.sup.2, R.sup.5, R.sup.8, R.sup.11 are each selected, identically or differently, from a straight-chain, branched or cyclic alkyl group having 4 to 10 carbon atoms, a straight-chain, branched or cyclic alkoxy group having 3 to 10 carbon atoms, an aralkyl group having 7 to 30 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.20 and where one or more H atoms in the above-mentioned groups may be replaced by D, F, Cl or CN, or an aromatic ring system having 6 to 30 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.20; R.sup.20 is on each occurrence, identically or differently, selected from D, F, or a straight-chain alkyl group having 1 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.21, or an aromatic ring system having 5 to 30 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.21, where two or more radicals R.sup.20 may be joined to form an aromatic ring system or a (poly)cyclic alkyl group, which may in each case be substituted by one or more radicals R.sup.21; R.sup.21 is on each occurrence, identically or differently, selected from H, D, F, or a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, or an alkenyl or alkynyl group having 2 to 10 carbon atoms, or an aromatic ring system having 5 to 30 aromatic ring atoms, where two or more radicals R.sup.21 may be joined to form an aromatic ring system or a (poly)cyclic alkyl group.

4. Electronic device according to any one of claims 1 to 3, characterized in that R.sup.2, R.sup.5, R.sup.8, R.sup.11 are each selected, identically or differently, from branched or cyclic alkyl groups represented by the general following formula (R-a) ##STR00193## wherein R.sup.22, R.sup.23, R.sup.24 are at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.25, and where two of radicals R.sup.22, R.sup.23, R.sup.24 or all radicals R.sup.22, R.sup.23, R.sup.24 may be joined to form a (poly)cyclic alkyl group, which may be substituted by one or more radicals R.sup.25; R.sup.25 is at each occurrence, identically or differently, selected from a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms; with the proviso that at each occurrence at least one of radicals R.sup.22, R.sup.23 and R.sup.24 is other than H, with the proviso that at each occurrence all of radicals R.sup.22, R.sup.23 and R.sup.24 together have at least 4 carbon atoms and with the proviso that at each occurrence, if two of radicals R.sup.22, R.sup.23, R.sup.24 are H, the remaining radical is not a straight-chain; or from branched or cyclic alkoxy groups represented by the general following formula (R-b) ##STR00194## wherein R.sup.26, R.sup.27, R.sup.28 are at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.25 as defined above, and where two of radicals R.sup.26, R.sup.27, R.sup.28 or all radicals R.sup.26, R.sup.27, R.sup.28 may be joined to form a (poly)cyclic alkyl group, which may be substituted by one or more radicals R.sup.25 as defined above; with the proviso that at each occurrence only one of radicals R.sup.26, R.sup.27 and R.sup.28 may be H; or from aralkyl groups represented by the general following formula (R-c) ##STR00195## wherein R.sup.29, R.sup.30, R.sup.31 are at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.32, or an aromatic ring system having 6 to 30 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.32, and where two or all of radicals R.sup.29, R.sup.30, R.sup.31 may be joined to form a (poly)cyclic alkyl group or an aromatic ring system, each of which may be substituted by one or more radicals R.sup.32; R.sup.32 is at each occurrence, identically or differently, selected from a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, or an aromatic ring system having 6 to 24 aromatic ring atoms; with the proviso that at each occurrence at least one of radicals R.sup.29, R.sup.30 and R.sup.31 is other than H and that at each occurrence at least one of radicals R.sup.29, R.sup.30 and R.sup.31 is or contains an aromatic ring system having at least 6 aromatic ring atoms; or from aromatic ring systems represented by the general following formula (R-d) ##STR00196## wherein R.sup.40 to R.sup.44 is at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.32, or an aromatic ring system having 6 to 30 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.32, and where two or more of radicals R.sup.40 to R.sup.44 may be joined to form a (poly)cyclic alkyl group or an aromatic ring system, each of which may be substituted by one or more radicals R.sup.32 as defined above.

5. Electronic device according to any one of claims 1 to 4, characterized in that R.sup.2, R.sup.5, R.sup.8, R.sup.11 are identical.

6. Electronic device according to any one of claims 1 to 5, characterized in that the compound of formula (I) represents a compound of general formulae (III) or (IV) ##STR00197## wherein R.sup.40, R.sup.42, R.sup.44 are at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.32, or an aromatic ring system having 6 to 30 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.32; where R.sup.32 is as defined in claim 4; with the proviso that at least one of R.sup.40, R.sup.42, R.sup.44 is other than H; or ##STR00198## wherein R.sup.41, R.sup.43 are at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.32, or an aromatic ring system having 6 to 30 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.32; where R.sup.32 is as defined in claim 4; with the proviso that at least one of R.sup.41, R.sup.43 is other than H.

7. Electronic device according to any one of claims 1 to 6, characterized in that R.sup.42 is at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.32; R.sup.40, R.sup.44 are at each occurrence, identically or differently, selected from an aromatic ring system having 6 to 30 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.32; where R.sup.32 is as defined in claim 4.

8. Electronic device according to any one of claims 1 to 6, characterized in that R.sup.40, R.sup.42, R.sup.44 are at each occurrence, identically or differently, selected from an aromatic ring system having 6 to 30 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.32; where R.sup.32 is as defined in claim 4.

9. Electronic device according to any one of claims 1 to 8, characterized in that the compound of formula (I) represents any one of a compound of general formulae (IIIa), (IIIb) or (IIIc) ##STR00199## wherein in each of formulae (IIIa), (IIIb) and (IIIc) the phenyl groups indicated with —R.sup.32 are unsubstituted or substituted with one or more radicals R.sup.32; R.sup.42 and R.sup.44 are at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.32; where R.sup.32 is as defined in claim 4.

10. Electronic device according to any one of claims 1 to 6, characterized in that R.sup.42 is at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, or an aromatic ring system having 6 to 30 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.32; R.sup.40, R.sup.44 are at each occurrence identically selected from a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, which may in each case be substituted by one or more radicals R.sup.32; and R.sup.32 is as defined in claim 4.

11. Electronic device according to any one of claims 1 to 10, characterized in that the organic layer comprises the sterically hindered fluorescent emitter compound and the sensitizer compound, said organic layer preferably being the emitting layer.

12. Electronic device according to any one of claims 1 to 11, characterized in that the organic layer comprises the sterically hindered fluorescent emitter compound, the sensitizer compound and at least one organic functional material selected from the group consisting of HTM, HIM, HBM, p-dopant, ETM, EIM, EBM, n-dopant, fluorescent emitter, phosphorescent emitter, delayed fluorescent material, matrix material, host material, wide band gap material, quantum material (preferably quantum dot), said organic layer preferably being the emitting layer.

13. Compound of the formula (III) or (IV) as defined in claim 6, characterised in that the radicals R.sup.40, R.sup.42, R.sup.44 and R.sup.41, R.sup.43 are defined as follows: R.sup.40 to R.sup.44 are at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.32, or an aromatic ring system having 6 to 24 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.32; and R.sup.32 is at each occurrence, identically or differently, selected from a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched or cyclic alkyl group having 3 to 10 carbon atoms, or an aromatic ring system having 6 to 24 aromatic ring atoms.

14. Compound according to claim 13, characterised in that the radicals R.sup.40, R.sup.42, R.sup.44 are defined as follows: R.sup.42 is at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched alkyl group having 3 to 10 carbon atoms; R.sup.40, R.sup.44 are at each occurrence, identically or differently, selected from an aromatic ring system having 6 to 24 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.32; R.sup.32 is at each occurrence, identically or differently, selected from a straight-chain alkyl group having 1 to 6 carbon atoms, or a branched alkyl group having 3 to 6 carbon atoms.

15. Compound according to claim 13, characterised in that the radicals R.sup.40, R.sup.42, R.sup.44 are defined as follows: R.sup.40, R.sup.42, R.sup.44 are at each occurrence, identically or differently, selected from an aromatic ring system having 6 to 24 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.32; R.sup.32 is at each occurrence, identically or differently, selected from a straight-chain alkyl group having 1 to 6 carbon atoms, or a branched alkyl group having 3 to 6 carbon atoms.

16. Compound according to any one of claims 13 to 15, characterized in that the compound of formula (III) represents any one of a compound of general formulae (IIId), (IIIe) or (IIIf) ##STR00200## in each of formulae (IIId), (IIIe) and (IIIf) the phenyl groups indicated with —R.sup.32 are unsubstituted or substituted with one or more radicals R.sup.32; R.sup.42 and R.sup.44 are at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched alkyl group having 3 to 10 carbon atoms, where the above-mentioned groups may each be substituted by one or more radicals R.sup.32; and R.sup.32 is at each occurrence, identically or differently, selected from a straight-chain alkyl group having 1 to 6 carbon atoms, or a branched alkyl group having 3 to 6 carbon atoms.

17. Compound according to claim 13, characterised in that the radicals R.sup.40, R.sup.42, R.sup.44 are defined as follows: R.sup.42 is at each occurrence, identically or differently, selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched alkyl group having 3 to 10 carbon atoms, or an aromatic ring system having 6 to 24 aromatic ring atoms, which may in each case be substituted by one or more radicals R.sup.32; R.sup.40, R.sup.44 are at each occurrence, identically or differently, selected from a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched alkyl group having 3 to 10 carbon atoms, which may in each case be substituted by one or more radicals R.sup.32; and R.sup.32 is at each occurrence, identically or differently, selected from a straight-chain alkyl group having 1 to 6 carbon atoms, or a branched alkyl group having 3 to 6 carbon atoms.

18. Compound according to claim 17, characterised in that the radicals R.sup.40, R.sup.42, R.sup.44 are defined as follows: R.sup.42 is at each occurrence identically selected from H, a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched alkyl group having 3 to 10 carbon atoms, R.sup.40, R.sup.44 are at each occurrence identically selected from a straight-chain alkyl group having 1 to 10 carbon atoms, or a branched alkyl group having 3 to 10 carbon atoms.

19. Composition comprising a compound according to one or more of claims 13 to 18 and at least one organic or inorganic functional material selected from the group consisting of HTM, HIM, HBM, p-dopant, ETM, EIM, EBM, n-dopant, fluorescent emitter, phosphorescent emitter, delayed fluorescent material, matrix material, host material, wide band gap material, quantum material (preferably quantum dot).

20. Formulation comprising at least one compound according to any one of claims 13 to 18 or a composition according to claim 19 and at least one solvent.

21. Process for the preparation of the compounds of the formula (III) according to any one of claims 13 to 18, characterised in that at least the following step a) is carried out: a) Organometallic coupling under Suzuki conditions between the 1-C, 5-C, 8-C and 11-C atoms of the perylene basic skeleton and a substituted or unsubstituted aromatic group Ar having 6 to 24 aromatic ring atoms, which is employed as starting material Ar—X, where X is any desired suitable leaving group, preferably selected from a halide, a boronic acid, a boronic ester, a tosylate or a triflate.

22. Use of a compound according to any one of claims 13 to 18, or a composition according to claim 19, or a formulation according to claim 20 in an electronic device, preferably in an organic electroluminescent device.

23. Electronic device comprising a composition according to claim 19, or a formulation according to claim 20, or a compound according to any one of claims 13 to 18.

24. Electronic device according to any of claims 1 to 12 or 23, which is preferably an organic electroluminescent device selected from 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 photo-receptors, organic field-quench devices (OFQDs), organic light-emitting electrochemical cells (OLECs, LECs, LEECs), organic laser diodes (O-lasers) and organic light emitting diodes (OLEDs).

Description

A) SYNTHESES EXAMPLES

[0189] ##STR00173##

Synthesis of Triflate Coupling Partner:

[0190] ##STR00174##

Example Synthesis of Triflate Coupling Partner

3-chloro-4′-methyl-[1,1′-biphenyl]-2-ol

[0191] ##STR00175##

[0192] Under an argon atmosphere, an oven dried flask is equipped with 2-bromo-6-chlorophenol (100.0 g, 0.48 mol, 1.0 equiv.), 4-methylphenyl-boronic acid (65.3 g, 0.48 mol, 1.0 equiv.), potassium carbonate (200.0 g, 1.45 mol, 3.0 equiv.) and bis(tri-tert-butylphosphine)palladium(0) (5.1 g, 0.01 mmol, 0.02 equiv). Toluene (1500 mL) and water (500 mL) are added and the reaction mixture is refluxed for 24 h. The organic phase is separated and concentrated. The crude product is purified by column chromatography. The desired product is obtained as a white solid (100.6 g, 0.46, 96%).

3′,5′-dimethyl-3-(4-methylphenyl)-[1,1′-biphenyl]-2-ol

[0193] ##STR00176##

[0194] Under an argon atmosphere, an oven dried flask is equipped with 3-chloro-4′-methyl-[1,1′-biphenyl]-2-ol (100.0 g, 0.46 mol, 1.0 equiv.), 3,5-dimethylphenyl-boronic acid (149.98, 67.0 g, 1.0 equiv.), potassium carbonate (193.5 g, 1.38 mmol, 3.0 equiv.) and chloro[(tricyclohexylphosphine)-2-(2′-aminobiphenyl)]palladium(II) (5.9 g, 0.01 mmol, 0.02 equiv). Toluene (1500 mL) and water (500 mL) are added and the reaction mixture is refluxed for 24 h. The organic phase is separated and concentrated. The crude product is purified by column chromatography. The desired product is obtained as a white solid (119.4 g, 0.41 mol, 90%)

3′,5′-dimethyl-3-(4-methylphenyl)-[1,1′-biphenyl]-2-yl trifluoromethanesulfonate

[0195] ##STR00177##

[0196] Under an argon atmosphere, an oven dried flask is equipped with 3′,5′-dimethyl-3-(4-methylphenyl)-[1,1′-biphenyl]-2-ol (110 g, 0.38 mol, 1.0 equiv.) in DCM (1000 mL). The mixture is cooled to 0° C. Pyridine (60. g, 61.3 mL, 0.76 mol, 2.0 equiv.) is added. Then trifluoromethanesulfonic anhydride (130.0 g, 77.5 mL, 0.46 mol, 1.2 equiv.) in DCM (300 mL) is added slowly. The reaction mixture is allowed to warm to rt overnight. The reaction mixture is washed with 3 M hydrochloric acid (400 mL) and saturated sodium hydrogen carbonate solution (400 mL). The organic phase is concentrated. The crude product is purified by recrystallization from methanol. The desired product is obtained as white solid (143.0 g, 0.34 mol, 90%).

2,5,8,11-Tetrakis(2,6-dimethyl-phenyl)-perylene

[0197] ##STR00178##

[0198] Under an argon atmosphere, an oven dried flask is equipped with a magnetic stir bar, 2,5,8,11-tetra-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-perylene (40.0 g, 52.9 mmol, 1.0 equiv.), 2-Bromo-1,3-dimethyl-benzene (293.7 g, 212.8 mL, 1587.0 mmol, 30.0 equiv.) and cesium carbonate (137.9 g, 423.2 mmol, 8.0 equiv.). Toluene (2000 mL) is then added and the reaction mixture is degassed with Ar. Tetrakis(triphenylphoshine)palladium (6.11 g, 5.3 mmol, 0.1 equiv.) is then added and the reaction mixture is stirred with heating to reflux for 72 h. The resulting precipitate is filtered off, and methanol (1000 ml) is added to the filtrate. The resulting precipitate is collected and the combined precipitates are purified by hot extraction, recrystallization and sublimation. The desired product is thus isolated as a yellow solid (4.5 g, 6.73 mmol, 12.7%)

2,5,8,11-Tetrakis(2,6-diphenyl-phenyl)-perylene

[0199] ##STR00179##

[0200] Under an argon atmosphere, an oven dried flask is equipped with a magnetic stir bar, 2,5,8,11-tetra-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-perylene (38.0 g, 50.3 mmol, 1.0 equiv.), 3-phenyl-[1,1′-biphenyl]-2-yl-trifluoromethanesulfonate (95.1 g, 251.3 mmol, 5.0 equiv.) and sodium metaborate tetrahydrate (69.3 g, 502.5 mmol, 10.0 equiv.). THF (1500 mL) and water (500 mL) are then added and the reaction mixture is degassed with Ar. Tetrakis(triphenylphoshine)palladium (5.81 g, 5.0 mmol, 0.1 equiv.) is then added and the reaction mixture is stirred with heating to reflux for 72 h. The reaction mixture is cooled to RT and the organic phase is collected and concentrated. The crude product is purified by hot extraction, recrystallization and sublimation. The desired product is thus isolated as a yellow solid (6.8 g, 5.8 mmol, 11.6%).

B) FABRICATION OF OLEDS

[0201] Glass plates coated with structured ITO (50 nm, indium tin oxide) are wet-cleaned (dishwasher, Merck Extran cleaner). The substrates are then treated with UV/ozone for 15 minutes. A 20 nm PEDOT:PSS layer is then spin-coated onto the substrates (2800 U/min). The substrates are dried again for 10 minutes on the hot plate at 180° C. After the fabrication, the OLEDs are encapsulated for protection against oxygen and water vapor. The exact layer structure of the OLEDs (organic light emitting diodes) can be found in the examples. The materials used to prepare the OLEDs are shown in Table 2.

[0202] All materials are thermally evaporated in a vacuum chamber. In this case, the emission layer(s) always consist(s) of at least one matrix material (host material), a phosphorescent sensitizer (PS) and a fluorescent emitter (FE). Sensitizer and fluorescent emitter (FE) are added to the host material (H) by co-evaporation in a certain volume fraction. An indication such as H-01:PS-01(5%):FE-01(3%) means that the material H-01 is present in a volume fraction of 92%, PS-01 is present in a volume fraction of 5% and FE-01 is present in a volume fraction of 3% in the layer. Similarly, the electron transport layer may consist of a mixture of two materials.

[0203] The OLEDs are characterised by standard methods. For this purpose, the electroluminescence spectra are recorded, the current efficiency (measured in cd/A) and the external quantum efficiency (EQE, measured in percent) as a function of the luminous density assuming Lambert emission characteristics are calculated from current/voltage/luminous density characteristic lines (IUL characteristic lines). The indication U100 indicates the voltage required for a luminance of 100 cd/m.sup.2. EQE100 refers to the external quantum efficiency at an operating luminance of 100 cd/m.sup.2.

[0204] The phosphorescent sensitizers used are the compounds PS-01 and PS-02. The fluorescent emitters used are the compounds FE-01, FE-02 and FE-03.

[0205] OLEDs with Blue Emission:

[0206] OLEDs consist of the following layer sequence, which is applied to the substrate after the PEDOT:PSS-treatment:

[0207] 20 nm HTM:pD (95%:5%), 30 nm HTM, 10 nm H-02, 25 nm H-01:PS:FE, 10 nm H-01, 20 nm ETM:LiQ (50%:50%), aluminum (100 nm).

[0208] Table 1 below lists the results for various combinations of host, sensitizer and fluorescent emitter. The EQE and voltage at 100 cd/in.sup.2 are given for the respective experiments.

TABLE-US-00003 TABLE 1 Experiments with blue emitting OLEDs EQE100 U100 Exp. Host Sensitizer FE [%] [V] 1 H-01 PS-01 (15%) FE-01 10.16 3.78 (1%) 2 H-01 PS-01 (15%) FE-01 6.77 3.91 (2%) 3 H-01 PS-01 (15%) FE-01 5.34 4 (3%) 4 H-01 PS-01 (15%) FE-02 9.32 3.89 (2%) 5 H-01 PS-01 (15%) FE-02 7.7 4.06 (3%) 6 H-01 PS-01 (15%) FE-03 19.67 3.63 (1%) 7 H-01 PS-01 (15%) FE-03 17.93 3.67 (2%) 8 H-01 PS-01 (15%) FE-03 14.77 3.68 (3%) 9 H-01 PS-02 (5%)  FE-01 13 3.33 (1%) 10 H-01 PS-02 (5%)  FE-01 9.5 3.37 (2%) 11 H-01 PS-02 (5%)  FE-01 8.4 3.4 (3%) 12 H-01 PS-02 (5%)  FE-02 12.3 3.28 (2%) 13 H-01 PS-02 (5%)  FE-02 11.2 3.28 (3%) 14 H-01 PS-02 (5%)  FE-03 18.7 3.23 (1%) 15 H-01 PS-02 (5%)  FE-03 15.8 3.24 (2%) 16 H-01 PS-02 (5%)  FE-03 13.5 3.28 (3%)

Results

[0209] Table 1 shows that blue-emitting OLEDs comprising FE-TM, FE-02 and FE-03 as fluorescent emitters in an emission layer containing a phosphorescent sensitizer are performant in terms of efficiency (EQE) and operating voltage (U100). More particularly, blue emitting OLEDs comprising FE-02 and FE-03, especially FE-03, achieve excellent results in terms of efficiency, while the operating voltage is relatively low.

TABLE-US-00004 TABLE 2 Structures of the OLED materials [00180] HTM [00181] p-D [00182] ETM [00183] LiQ [00184] H-01 [00185] H-02 [00186] PS-01 [00187] PS-02 [00188] FE-01 [00189] FE-02 [00190] FE-03