Compound, Semiconductor Layer Comprising Compound and Organic Electronic Device

Abstract

The present invention relates to a compound represented by Formula (I) wherein M is Cu, Zn, Al, Hf; or Formula (V).

##STR00001##

Claims

1-16. (canceled)

17. A compound selected from the group comprising: Formula (I): ##STR00082## wherein M is Cu, Zn, Al, Hf; L is a charge-neutral ligand, which coordinates to the metal M; n is an integer selected from 2, 3 or 4, which corresponds to the oxidation number of M; m is an integer selected from 0 to 2; R.sup.1 is independently selected from substituted or unsubstituted C.sub.6 to C.sub.24 aryl and substituted or unsubstituted C.sub.2 to C.sub.24 heteroaryl group comprising at least 6 ring-forming atoms, wherein at least one substituent is selected from F, CN, substituted or unsubstituted C.sub.1 to C.sub.12 alkyl, partially or fully fluorinated C.sub.1 to C.sub.12 alkyl, substituted or unsubstituted C.sub.6 to C.sub.18 aryl, and substituted or unsubstituted C.sub.2 to C.sub.18 heteroaryl, wherein the substituents of the substituted or unsubstituted C.sub.1 to C.sub.12 alkyl, substituted or unsubstituted C.sub.6 to C.sub.18 aryl, and substituted or unsubstituted C.sub.2 to C.sub.18 heteroaryl are selected from halogen, F, CN, C.sub.1 to C.sub.6 alkyl, CF.sub.3; wherein at least one substituent is selected from partially or fully fluorinated C.sub.1 to C.sub.12 alkyl, or CN; R.sup.2 is selected from CN, C.sub.1 to C.sub.4 alkyl, partially or perfluorinated C.sub.1 to C.sub.4 alkyl, or F; R.sup.3 is independently selected from substituted C.sub.1 to C.sub.12 alkyl, substituted or unsubstituted C.sub.6 to C.sub.24 aryl, and substituted or unsubstituted C.sub.2 to C.sub.24 heteroaryl group comprising at least 6 ring-forming atoms, wherein at least one substituent is selected from F, CN, substituted or unsubstituted C.sub.1 to C.sub.12 alkyl, partially or fully fluorinated C.sub.1 to C.sub.12 alkyl, substituted or unsubstituted C.sub.6 to C.sub.18 aryl, and substituted or unsubstituted C.sub.2 to C.sub.18 heteroaryl, wherein the substituents of the substituted or unsubstituted C.sub.1 to C.sub.12 alkyl, substituted or unsubstituted C.sub.6 to C.sub.18 aryl, and substituted or unsubstituted C.sub.2 to C.sub.18 heteroaryl are selected from F, CN, C.sub.1 to C.sub.6 alkyl, CF.sub.3; or Formula (V): ##STR00083## wherein R.sup.1 is selected from formula D69 ##STR00084## R.sup.2 is selected from CN, C.sub.1 to C.sub.4 alkyl, partially or perfluorinated C.sub.1 to C.sub.4 alkyl, or F; R.sup.3 is independently selected from substituted C.sub.1 to C.sub.12 alkyl, wherein at least one substituent is selected from F, CN, substituted or unsubstituted C.sub.1 to C.sub.12 alkyl, partially or fully fluorinated C.sub.1 to C.sub.12 alkyl, substituted or unsubstituted C.sub.6 to C.sub.18 aryl, and substituted or unsubstituted C.sub.2 to C.sub.18 heteroaryl, wherein the substituents of the substituted or unsubstituted C.sub.1 to C.sub.12 alkyl, substituted or unsubstituted C.sub.6 to C.sub.18 aryl, and substituted or unsubstituted C.sub.2 to C.sub.18 heteroaryl are selected from F, CN, C.sub.1 to C.sub.6 alkyl, CF.sub.3.

18. The compound represented by Formula (I) according to claim 17, wherein the compounds A1 to A12 are excluded: ##STR00085## ##STR00086## ##STR00087##

19. The compound represented by Formula (I) according to claim 17, wherein R.sup.2 is selected from CN, CH.sub.3, CF.sub.3, C.sub.2F.sub.5, C.sub.3F.sub.7 or F.

20. The compound represented by Formula (I) according to claim 17, wherein a R.sup.1 and/or R.sup.3 is selected from a substituted C.sub.6 to C.sub.24 aryl or substituted C.sub.2 to C.sub.24 heteroaryl group, wherein at least one substituent or at least two substituents of the substituted C.sub.6 to C.sub.24 aryl or substituted C.sub.2 to C.sub.24 heteroaryl group is selected from CN or partially or fully fluorinated C.sub.1 to C.sub.12 alkyl, partially or fully fluorinated C.sub.1 to C.sub.4 alkyl.

21. The compound represented by Formula (I) according to claim 17, wherein the compound of formula (I) comprises a group selected from the group comprising at least one CF.sub.3 group, at least two CF.sub.3 groups, at least three CF.sub.3 groups, at least four CF.sub.3 groups, at least two CF.sub.3 groups, at least one C.sub.2F.sub.5, at least two CF.sub.3 groups, at least one group selected from CN, F or CH.sub.3.

22. The compound represented by Formula (I) according to claim 17, wherein at least one of R.sup.1 and R.sup.3 is selected from the group comprising a substituted or unsubstituted C.sub.6 to C.sub.24 aryl, a substituted C.sub.2 to C.sub.24 heteroaryl group comprising at least 6 ring-forming atoms, a group of the following Formulas D1 to D71: ##STR00088## ##STR00089## ##STR00090## ##STR00091## ##STR00092## ##STR00093## ##STR00094## ##STR00095## ##STR00096## wherein the * denotes the binding position.

23. The compound represented by Formula (I) according to claim 17, wherein the compound represented by Formula I is selected from the following Formulas E1 to E20: ##STR00097## ##STR00098## ##STR00099## ##STR00100## ##STR00101## ##STR00102## ##STR00103## and more preferred wherein M is Cu(II) or AK(III), more preferred Cu(II).

24. The compound represented by Formula (I) according to claim 17, wherein the compound represented by Formula I is selected from the following Formulas G1 to G8: ##STR00104## ##STR00105## ##STR00106##

25. The compound represented by Formula (I) according to claim 17, wherein L is selected from the group comprising H.sub.2O, C.sub.2 to C.sub.40 mono-or multi-dentate ethers and C.sub.2 to C.sub.40 thioethers, C.sub.2 to C.sub.40 amines, C.sub.2 to C.sub.40 phosphine, C.sub.2 to C.sub.20 alkyl nitrile, C.sub.2 to C.sub.40 aryl nitrile, a compound according to Formula (II); ##STR00107## wherein R.sup.6 and R.sup.7 are independently selected from C.sub.1 to C.sub.20 alkyl, C.sub.1 to C.sub.20 heteroalkyl, C.sub.6 to C.sub.20 aryl, heteroaryl with 5 to 20 ring-forming atoms, halogenated or perhalogenated C.sub.1 to C.sub.20 alkyl, halogenated or perhalogenated C.sub.1 to C.sub.20 heteroalkyl, halogenated or perhalogenated C.sub.6 to C.sub.20 aryl, halogenated or perhalogenated heteroaryl with 5 to 20 ring-forming atoms, at least one R.sup.6 and R.sup.7 are bridged and form a 5 to 20 member ring, two R.sup.6 are bridged and form a 5 to 40 member ring, two R.sup.7 are bridged and form a 5 to 40 member ring, two R.sup.6 are bridged and form a 5 to 40 member ring comprising an unsubstituted or C.sub.1 to C.sub.12 substituted phenanthroline, two R.sup.6 are bridged and form a 5 to 40 member ring comprising an unsubstituted or C.sub.1 to C.sub.12 substituted phenanthroline.

26. The compound represented by Formula (I) according to claim 17, wherein n=2 or 3.

27. The compound represented by Formula (I) according to claim 17, wherein m is an integer selected from 0 or 1.

28. The compound represented by Formula (I) according to claim 17, wherein at least one of R.sup.1 and R.sup.3 are selected from a substituted C.sub.2 to C.sub.24 heteroaryl group comprising at least 6 ring-forming atoms, wherein the C.sub.2 to C.sub.24 heteroaryl group comprising at least 6 ring-forming atoms is selected from pyridyl, pyrimidinyl, pyrazinyl, triazinyl.

29. The compound represented by Formula (V) according to claim 17, wherein the compound of formula (V) is selected from formulas L1 to L8: ##STR00108## ##STR00109## ##STR00110## and more preferred the compound of formula (V) is selected from formulas L1 to L6.

30. A semiconductor material comprising at least one compound of Formula (I) or Formula (V) according to claim 17.

31. A semiconductor material according to claim 30, wherein the semiconductor material comprises in addition a matrix material selected from the group of at least one covalent matrix compound or of at least one substantially covalent matrix compound.

32. An organic electronic device comprising a compound selected from the group of Formula (I) or Formula (V) according to claim 17, wherein the organic electronic device is selected from devices comrising a light emitting device, thin film transistor, a battery, a display device, a photovoltaic cell, a part of a display device or lighting device.

33. An organic electronic device comprising a semiconductor material according to claim 30, wherein the organic electronic device is selected from devices comprising a light emitting device, thin film transistor, a battery, a display device, a photovoltaic cell, part of a display device or lighting device.

Description

DESCRIPTION OF THE DRAWINGS

[0436] The aforementioned components, as well as the claimed components and the components to be used in accordance with the invention in the described embodiments, are not subject to any special exceptions with respect to their size, shape, material selection and technical concept such that the selection criteria known in the pertinent field can be applied without limitations.

[0437] Additional details, characteristics and advantages of the object of the invention are disclosed in the dependent claims and the following description of the respective figures which in an exemplary fashion show preferred embodiment according to the invention. Any embodiment does not necessarily represent the full scope of the invention, however, and reference is made therefore to the claims and herein for interpreting the scope of the invention. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are intended to provide further explanation of the present invention as claimed.

[0438] FIG. 1 is a schematic sectional view of an organic electronic device, according to an exemplary embodiment of the present invention;

[0439] FIG. 2 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention;

[0440] FIG. 3 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention.

[0441] FIG. 4 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention;

[0442] FIG. 5 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention.

[0443] FIG. 6 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention.

[0444] FIG. 1 is a schematic sectional view of an organic electronic device 101, according to an exemplary embodiment of the present invention. The organic electronic device 101 includes a substrate (110), an anode layer (120), a hole injection layer comprising a metal complex according to formula (I) (130), a photoactive layer (PAL) (151) and a cathode layer (190).

[0445] FIG. 2 is a schematic sectional view of an organic light-emitting diode (OLED) 100, according to an exemplary embodiment of the present invention. The OLED 100 includes a substrate (110), an anode layer (120), a hole injection layer comprising a metal complex according to formula (I) (130), an emission layer (EML) (150) and a cathode layer (190).

[0446] FIG. 3 is a schematic sectional view of an organic light-emitting diode (OLED) 100, according to an exemplary embodiment of the present invention. The OLED 100 includes a substrate (110), an anode layer (120), a hole injection layer comprising a metal complex according to formula (I) (130), a hole transport layer (HTL) (140), an emission layer (EML) (150), an electron transport layer (ETL) (160) and a cathode layer (190).

[0447] FIG. 4 is a schematic sectional view of an organic light-emitting diode (OLED) 100, according to an exemplary embodiment of the present invention. The OLED 100 includes a substrate (110), an anode layer (120), a hole injection layer comprising a metal complex according to formula (I) (130), a hole transport layer (HTL) (140), an electron blocking layer (EBL) (145), an emission layer (EML) (150), a hole blocking layer (HBL) (155), an electron transport layer (ETL) (160), an optional electron injection layer (EIL) (180), and a cathode layer (190).

[0448] FIG. 5 is a schematic sectional view of an organic light-emitting diode (OLED) 100, according to an exemplary embodiment of the present invention. The OLED 100 includes a substrate (110), an anode layer (120) that comprises a first anode sub-layer (121) and a second anode sub-layer (122), a hole injection layer comprising a metal complex according to formula (I) (130), a hole transport layer (HTL) (140), an electron blocking layer (EBL) (145), an emission layer (EML) (150), a hole blocking layer (EBL) (155), an electron transport layer (ETL) (160) and a cathode layer (190).

[0449] FIG. 6 is a schematic sectional view of an organic light-emitting diode (OLED) 100, according to an exemplary embodiment of the present invention. The OLED 100 includes a substrate (110), an anode layer (120) that comprises a first anode sub-layer (121), a second anode sub-layer (122) and a third anode sub-layer (123), a hole injection layer comprising a metal complex according to formula (I) (130), a hole transport layer (HTL) (140), an electron blocking layer (EBL) (145), an emission layer (EML) (150), a hole blocking layer (EBL) (155), an electron transport layer (ETL) (160) and a cathode layer (190). The layers are disposed exactly in the order as mentioned before.

[0450] In the description above the method of manufacture an organic electronic device 101 of the present invention is for example started with a substrate (110) onto which an anode layer (120) is formed, on the anode layer (120), a hole injection layer comprising a metal complex according to formula (I) (130), a photoactive layer (151) and a cathode electrode 190 are formed, exactly in that order or exactly the other way around.

[0451] In the description above the method of manufacture an OLED of the present invention is started with a substrate (110) onto which an anode layer (120) is formed, on the anode layer (120), a hole injection layer comprising a metal complex according to formula (I) (130), optional a hole transport layer (140), optional an electron blocking layer (145), an emission layer (150), optional a hole blocking layer (155), optional an electron transport layer (160), optional an electron injection layer (180), and a cathode electrode 190 are formed, exactly in that order or exactly the other way around.

[0452] The semiconductor layer comprising a metal complex according to formula (I) (130) can be a hole injection layer.

[0453] While not shown in FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5 and FIG. 6, a capping layer and/or a sealing layer may further be formed on the cathode electrodes 190, in order to seal the OLEDs 100. In addition, various other modifications may be applied thereto.

[0454] Hereinafter, one or more exemplary embodiments of the present invention will be described in detail with, reference to the following examples. However, these examples are not intended to limit the purpose and scope of the one or more exemplary embodiments of the present invention.

LUMO Levels of Compounds of Formula (I)

[0455] The LUMO levels of the compounds of formula (I) are calculated with the program package TURBOMOLE V6.5 (TURBOMOLE GmbH, Litzenhardtstrasse 19, 76135 Karlsruhe, Germany).

[0456] The energies of the LUMO are obtained from a geometry optimization at the TPSSh/Def2-SVP level of the theory with inclusion of solvent effects via the COSMO (COnductor-like Screening MOdel) model with a dielectric constant (?) set to be equal to 3. For M=Hf, the basis set Def-SV(P) was used instead. All the calculations were performed with TURBOMOLE. If more than one conformation is viable, the conformation with the lowest total energy is selected. If more than one spin state is viable, the spin state with the lowest total energy is selected.

HOMO and LUMO Levels of the Matrix Compound, Compound of Formula (III) or a Compound of Formula (IV)

[0457] The HOMO and LUMO levels of the matrix compound, compound of formula (III) or a compound of formula (IV) are calculated with the program package TURBOMOLE V6.5 (TURBOMOLE GmbH, Litzenhardtstrasse 19, 76135 Karlsruhe, Germany). The optimized geometries and the HOMO and LUMO energy levels of the molecular structures are determined by applying the hybrid functional B3LYP with a 6-31G* basis set in the gas phase. If more than one conformation is viable, the conformation with the lowest total energy is selected. If calculated by this method, the HOMO level of N2,N2,N2,N2,N7,N7,N7,N7-octakis(4-methoxyphenyl)-9,9-spirobi[fluorene]-2,2,7,7-tetraamine is ?4.27 eV.

Melting Point T.SUB.m

[0458] The melting point T.sub.m is determined as peak temperatures from the DSC curves of the above TGA-DSC measurement or from separate DSC measurements (Mettler Toledo DSC822e, heating of samples from room temperature to completeness of melting with heating rate 10 K/min under a stream of pure nitrogen. Sample amounts of 4 to 6 mg are placed in a 40 ?L Mettler Toledo aluminum pan with lid, a <1 mm hole is pierced into the lid).

Decomposition Temperature T.SUB.dec

[0459] The decomposition temperature T.sub.dec is measured by loading a sample of 9 to 11 mg into a Mettler Toledo 100 ?L aluminum pan without lid under nitrogen in a Mettler Toledo TGA-DSC 1 machine. The following heating program was used: 25? C. isothermal for 3 min; 25? C. to 600? C. with 10 K/min. The decomposition temperature was determined based on the onset of the decomposition in TGA.

Sublimation Temperature

[0460] Under nitrogen in a glovebox, 0.5 to 5 g compound are loaded into the evaporation source of a sublimation apparatus. The sublimation apparatus consist of an inner glass tube consisting of bulbs with a diameter of 3 cm which are placed inside a glass tube with a diameter of 3.5 cm. The sublimation apparatus is placed inside a tube oven (Creaphys DSU 05/2.1). The sublimation apparatus is evacuated via a membrane pump (Pfeiffer Vacuum MVP 055-3C) and a turbo pump (Pfeiffer Vacuum THM071 YP). The pressure is measured between the sublimation apparatus and the turbo pump using a pressure gauge (Pfeiffer Vacuum PKR 251). When the pressure has been reduced to 10?5 mbar, the temperature is increased in increments of 10 to 30 K till the compound starts to be deposited in the harvesting zone of the sublimation apparatus. The temperature is further increased in increments of 10 to 30 K till a sublimation rate is achieved where the compound in the source is visibly depleted over 30 min to 1 hour and a substantial amount of compound has accumulated in the harvesting zone. The sublimation temperature, also named Tsubl, is the temperature inside the sublimation apparatus at which the compound is deposited in the harvesting zone at a visible rate and is measured in degree Celsius.

Rate Onset Temperature

[0461] The rate onset temperature (TRO) is determined by loading 100 mg compound into a VTE source. As VTE source a point source for organic materials may be used as supplied by Kurt J. Lesker Company (www.lesker.com) or CreaPhys GmbH (http://www.creaphys.com). The VTE source is heated at a constant rate of 15 K/min at a pressure of less than 10?5 mbar and the temperature inside the source measured with a thermocouple. Evaporation of the compound is detected with a QCM detector which detects deposition of the compound on the quartz crystal of the detector. The deposition rate on the quartz crystal is measured in Angstrom per second. To determine the rate onset temperature, the deposition rate is plotted against the VTE source temperature. The rate onset is the temperature at which noticeable deposition on the QCM detector occurs. For accurate results, the VTE source is heated and cooled three time and only results from the second and third run are used to determine the rate onset temperature.

[0462] To achieve good control over the evaporation rate of an organic compound, the rate onset temperature may be in the range of 200 to 255? C. If the rate onset temperature is below 200? C. the evaporation may be too rapid and therefore difficult to control. If the rate onset temperature is above 255? C. the evaporation rate may be too low which may result in low tact time and decomposition of the organic compound in VTE source may occur due to prolonged exposure to elevated temperatures.

[0463] The rate onset temperature is an indirect measure of the volatility of a compound. The higher the rate onset temperature the lower is the volatility of a compound.

General Method for Preparation of the Ink Formulation

[0464] To prepare the ink formulation, under inert atmosphere the compounds were weighed into vials. Then, the solvent was added. The mixture was stirred at 60? C. for 10 min. After cooling to room temperature, an aliquot of benzonitrile solutions was added to the anisole solution to obtain a solution with a ratio of 5:1 of anisole to benzonitrile solution. The resulting solution was stirred again for at least 10 min at room temperature. The resulting ink formulation had a solid content of 3 wt.-%.

EXPERIMENTAL DATA

Synthesis Examples

[0465] Compounds of formula (I) may be prepared by known methods or as described below.

Synthesis of 1,3-bis(3,5-bis(trifluoromethyl)phenyl)propane-1,3-dione

[0466] ##STR00054##

[0467] To a suspension of NaH (2.34 g, 100 mmol) in 100 ml THF was added dropwise 1-(3,5-bis(trifluoromethyl)phenyl)ethan-1-one (10 g, 39 mmol) and methyl 3,5-bis(trifluoromethyl)benzoate (11.7 g, 43 mmol) dissolved together in 50 ml THF. The resulting mixture was refluxed for 30 h. The reaction mixture was cooled to RT and ice-cold 10% HCl (200 ml) was added during rapidly stirring. Et.sub.2O was added (250 ml) and organic phase was separated, washed with water and dried over Na.sub.2SO.sub.4, concentrated. Crude product was triturated in hexane with traces of Et.sub.2O for 3 h, filtered, washed with hexane and dried. Yield 13.4 g (69%).

Synthesis of 2-(3,5-bis(trifluoromethyl)benzoyl)-3-(3,5-bis(trifluoromethyl)phenyl)-3-oxopropanenitrile

[0468] ##STR00055##

[0469] To a solution of 17.37 g (35 mmol) of 1,3-bis(3,5-bis(trifluoromethyl)phenyl)propane-1,3-dione and K.sub.2CO.sub.3 (7.26 g, 52.5 mmol) in THF-water was added p-Tolylsulfonylcyanid (9.51 g, 52.5 mmol) in one portion and the resulting mixture was stirred at RT for 3 h. The reaction mixture was cooled to 0? C., acidified with aq. 2M HCl, and extracted 2?500 ml of ethyl acetate. The combined organic phases were dried over MgSO4 and concentrated. Crude product was triturated in mixture of 100 ml hexane and 10 ml ethyl acetate for 1 h. Solid precipitate was filtered and washed with hexane. Filtrate was purified by chromatography on silica gel (DCM/Ethyl acetate/Hexane). Fractions with product were concentrated followed by acidic extraction (aq. 2M HCl/ethyl acetate). The combined organic phases were dried over MgSO4 and concentrated. Product was triturated in 20% Et.sub.2O in hexane for 2 h, solid was filtered, washed with hexane, and dried. Yield 9.52 g (52%).

Synthesis of bis(((Z)-1,3-bis(3,5-bis(trifluoromethyl)phenyl)-2-cyano-3-oxoprop-1-en-1-yl)oxy)copper (MC-1)

[0470] ##STR00056##

[0471] 2.42 g (4.64 mmol) of 2-(3,5-bis(trifluoromethyl)benzoyl)-3-(3,5-bis(trifluoromethyl)phenyl)-3-oxopropanenitrile were dissolved in 40 ml methanol and solution of 0.46 g (2.32 mmol) copper(II) acetate monohydrate in 30 ml methanol and 20 ml water was added. The mixture was stirred at room temperature overnight. The precipitate was filtered off, washed with water and dried in high vacuum. 2.29 g (89%) product was obtained as a green powder.

Synthesis of 2-(3,5-bis(trifluoromethyl)-[1,1-biphenyl]-4-carbonyl)-4,4,5,5,5-pentafluoro-3-oxopentanenitrile

[0472] ##STR00057##

[0473] To a solution of 16.7 g (35 mmol) of 1-(3,5-bis(trifluoromethyl)-[1,1-biphenyl]-4-yl)-4,4,5,5,5-pentafluoropentane-1,3-dione and K.sub.2CO.sub.3 (7.26 g, 52.5 mmol) in THF-water was added p-Tolylsulfonylcyanid (9.51 g, 52.5 mmol) in one portion and the resulting mixture was stirred at RT for 20 h. THF was removed and 300 ml water and 300 ml DCM were added and stirred in ice/water bath for 30 min. White solid was filtered and washed with 2?300 ml water and 2?300 ml DCM and dried. Crude material was suspended in 100 ml DCM and 60 ml 1M HCl for 30 min, Layers were separated. Organic phase was washed with 30 ml of 1M HCl. Combined aq. phases were washed with 100 ml DCM. Combined organic phases were washed with 100 ml water, dried over MgSO.sub.4 and concentrated at 40? C. 100 ml hexane was added and stirred with 5 ml DCM in ice/water bath for 1 h. Solid was filtered, washed with cold hexane and dried. 14.27 g (yield 81%).

Synthesis of bis(((Z)-1-(3,5-bis(trifluoromethyl)-[1,1-biphenyl]-4-yl)-2-cyano-4,4,5,5,5-pentafluoro-3-oxopent-1-en-1-yl)oxy)copper (MC-2)

[0474] ##STR00058##

[0475] 5.0 g (9.94mmol) of 2-(3,5-bis(trifluoromethyl)-[1,1-biphenyl]-4-carbonyl)-4,4,5,5,5-pentafluoro-3-oxopentanenitrile were dissolved in 50 ml methanol and 0.99 g (4.97mmol) copper(II) acetate monohydrate and 20 ml water were added. The mixture was stirred at room temperature overnight. The precipitate was filtered off, washed with water and dried in high vacuum. The crude product was crystallized from chloroform/ethyl acetate to obtain 3.60 g (68%) product as a green solid.

Synthesis of N-methoxy-N-methyl-2-(trifluoromethyl)isonicotinamide

[0476] ##STR00059##

[0477] Flask was charged with 2-(trifluoromethyl)isonicotinic acid (20.1 g, 100 mmol), dichloromethane (100 ml) and CDI (19.4 g, 120 mmol) was added within 10 min. RM (reaction mixture) was stirred at r.t. for 1.5 h. Then, N,O-dimethyl hydroxylamine hydrochloride (14.6 g, 150mmol) was added and reaction mixture was stirred at r.t. for 17 h (overnight). Reaction was quenched with 1 M sol. of NaOH (50 mL) and extracted with dichloromethane (2?100 mL). Combined organic layers were washed with water, brine and solvent was evaporated in vacuo to give colorless oil (20.5 g, yield 87%).

Synthesis of 1-(2-(trifluoromethyl)pyridin-4-yl)propan-1-one

[0478] ##STR00060##

[0479] Flask was charged with N-methoxy-N-methyl-2-(trifluoromethyl)isonicotinamide (20.3 g, 87 mmol), evacuated and filled with Ar. THF was added and RM was cooled to ?79? C. Then, EtMgBr (3M in THF, 130 mmol)) was added dropwise within 15 min. The reaction mixture was stirred at ?79? C. for 1 h and then 0? C. for 2 h. Upon completion, the reaction mixture was poured into sol. of NH.sub.4Cl and extracted with Et.sub.2O. Obtained red oil was purified by column chromatography (hexane-ethyl acetate) to give product as yellow liquid (13.2, yield 74%).

Synthesis of 2-methyl-1,3-bis(2-(trifluoromethyl)pyridin-4-yl)propane-1,3-dione

[0480] ##STR00061##

[0481] A flask was charged with 1-(2-(trifluoromethyl)pyridin-4-yl)propan-1-one (10.2 g, 50 mmol), evacuated and filled with Ar. THF was added, reaction mixture was cooled to 0? C. and NaH (2.4 g, 100 mmol) was added. Reaction mixture was stirred for 30 min. and 2,2,2-trifluoroethyl trifluoroacetate (5.9 g, 30 mmol) was added dropwise within 20 min and mixture was stirred at 0? C. for 30 min. Upon completion reaction was quenched at 0? C. by diluted HCl and extracted with Et.sub.2O, combined organic layers were washed with water, brine, dried over Na.sub.2SO.sub.4 and solvent was evaporated in vacuo. The residue was purified by column chromatography (Hexane, ethyl acetate). Obtained yellow solid was triturated with 20 mL of Et.sub.2O, filtrated off and washed with cold Et.sub.2O. Colorless product was obtained 4.42 g (47%).

Synthesis of bis(((Z)-2-methyl-3-oxo-1,3-bis(2-(trifluoromethyl)pyridin-4-yl)prop-1-en-1-yl)oxy)copper (MC-3)

[0482] ##STR00062##

[0483] 2.50 g (6.64 mmol) of 2-methyl-1,3-bis(2-(trifluoromethyl)pyridin-4-yl)propane-1,3-dione were dissolved in 25ml methanol and 0.66 g (3.32mmol) copper (II) acetate monohydrate and 10 ml water were added. The mixture was stirred at room temperature overnight. The precipitate was filtered off, washed with water and dried in high vacuum. The crude product was stirred in 200 mL hot ethyl acetate, filtered off and dried in high vacuum to obtain 1.97 g (73%) product as a green solid.

[0484] Further compounds according to the invention may be prepared by the methods described above or by methods known in the art.

General Procedure for Fabrication of OLEDs

[0485] General Procedure for Fabrication of Organic Electronic Devices Comprising a Semiconductor Layer Comprising a Metal Complex and a Matrix Compound wherein the Semiconductor Layer is Deposited in Vacuum

[0486] For inventive examples 1-1 to 1-7 and comparative examples 1-1 to 1-4 in Table 2 a glass substrate with an anode layer comprising a first anode sub-layer of 120 nm Ag, a second anode sub-layer of 8 nm ITO and a third anode sub-layer of 10 nm ITO was cut to a size of 50 mm?50 mm?0.7 mm, ultrasonically washed with water for 60 minutes and then with isopropanol for 20 minutes. The liquid film was removed in a nitrogen stream, followed by plasma treatment to prepare the anode layer. The plasma treatment was performed in an atmosphere comprising 97.6 vol.-% nitrogen and 2.4 vol.-% oxygen.

[0487] Then, the metal complex and the matrix compound were co-deposited in vacuum on the anode layer, to form a hole injection layer (HIL) having a thickness of 10 nm. The composition of the hole injection layer can be seen in Table 2. The formulae of the metal complexes can be seen in Table 1.

[0488] Then, the matrix compound was vacuum deposited on the HIL, to form a HTL having a thickness of 123 nm. The compound of formula (II) in the HTL is selected the same as the matrix compound in the HIL. The matrix compound can be seen in Table 2.

[0489] Then N-(4-(dibenzo[b,d]furan-4-yl)phenyl)-N-(4-(9-phenyl-9H-fluoren-9-yl)phenyl)-[1,1-biphenyl]-4-amine (CAS 1824678-59-2) was vacuum deposited on the HTL, to form an electron blocking layer (EBL) having a thickness of 5 nm.

[0490] Then 97 vol.-% H09 as EML host and 3 vol.-% BD200 (Sun Fine Chemicals, Korea) as fluorescent blue emitter dopant were deposited on the EBL, to form a blue-emitting first emission layer (EML) with a thickness of 20 nm.

[0491] Then a hole blocking layer was formed with a thickness of 5 nm by depositing 2-(3-(9,9-dimethyl-9H-fluoren-2-yl)-[1,1-biphenyl]-3-yl)-4,6-diphenyl-1,3,5-triazine on the emission layer EML.

[0492] Then the electron transporting layer having a thickness of 31 nm was formed on the hole blocking layer by depositing 50 wt.-% 4-(4-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)naphthalen-1-yl)-[1,1-biphenyl]-4-carbonitrile and 50 wt.-% of LiQ.

[0493] Then Ag:Mg (90:10 vol.-%) was evaporated at a rate of 0.01 to 1 ?/s at 10.sup.?7 mbar to form a cathode layer with a thickness of 13 nm on the electron transporting layer.

[0494] Then, K1 was deposited on the cathode layer to form a capping layer with a thickness of 75 nm.

[0495] The OLED stack is protected from ambient conditions by encapsulation of the device with a glass slide. Thereby, a cavity is formed, which includes a getter material for further protection.

General Method for Preparation of the Ink Formulation

[0496] To prepare the ink formulation, under inert atmosphere the compounds were weighed into vials. Then, the solvent was added. The mixture was stirred at 60? C. for 10 min. After cooling to room temperature, an aliquot of benzonitrile solutions was added to the anisole solution to obtain a solution with a ratio of 5:1 of anisole to benzonitrile solution. The resulting solution was stirred again for at least 10 min at room temperature. The resulting ink formulation had a solid content of 3 wt.-%.

Ink Formulation for Inventive Example 2-1

[0497] The ink formulation for example 2-1 has the following composition: 10 wt.-% MC-2: K1 in anisole:benzonitrile (5:1). To prepare the ink, solutions of 15 mg MC-2 in 0.8 ml benzonitrile and 139 mg K1 in 4.2 ml anisole were prepared as described above. 0.8 ml benzonitrile solution was added to the anisole solution and stirred as described above.

Ink Formulation for Inventive Example 2-2

[0498] The ink formulation for example 2-2 has the following composition: 10 wt.-% MC-3: K1 in anisole:benzonitrile (5:1). To prepare the ink, solutions of 15 mg MC-3 in 0.8 ml benzonitrile and 139 mg K1 in 4.2 ml anisole were prepared as described above. 0.8 ml benzonitrile solution was added to the anisole solution and stirred as described above.

General Procedure for Fabrication of Electronic Devices Comprising a Semiconductor Layer Comprising a Metal Complex and a Matrix Compound wherein the Semiconductor Layer is Deposited from Solution

[0499] For bottom-emission OLEDs, see Examples 2-1 and 2-2 in Table 3, a 15 ?/cm.sup.2 glass substrate with 90 nm ITO (available from Corning Co.) with the dimensions 150 mm?150 mm?0.7 mm was ultrasonically washed with isopropyl alcohol for 5 minutes and then with pure water for 5 minutes and dried at elevated temperature.

[0500] To form the hole injection layer having a thickness of 45 nm on the anode layer, the substrate is placed on a spin-coater with ITO side facing upwards and fixed with vacuum. 5 ml of ink formulation is applied with a syringe with filter (PTFE0.45 ?m) on the substrate. Spin-coating parameter are 850 rpm (3 sec ramp-up from zero to maximum speed) for 30 sec. The resulting film is dried at 60? C. for 1 minute on a hotplate. Next step is the cleaning of the substrate around the active area (to ensure a good encapsulation process after evaporation). An additional bake-out at 100? C. for 10 minutes on a hotplate is done. The composition of the hole injection layer can be seen in Table 3. The formulae of the metal complexes can be seen in Table 1.

[0501] Then, the substrate is transferred to a vacuum chamber.

[0502] Then, Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine was vacuum deposited on the HIL, to form a first HTL having a thickness of 89 nm.

[0503] Then N,N-di([1,1-biphenyl]-4-yl)-3-(9H-carbazol-9-yl)-[1,1-biphenyl]-4-amine (CAS 1464822-27-2) was vacuum deposited on the HTL, to form an electron blocking layer (EBL) having a thickness of 5 nm.

[0504] Then 97 vol.-% H09 (Sun Fine Chemicals, Korea) as EML host and 3 vol.-% BD200 (Sun Fine Chemicals, Korea) as fluorescent blue dopant were deposited on the EBL, to form a first blue-emitting emission layer (EML) with a thickness of 20 nm.

[0505] Then a hole blocking layer is formed with a thickness of 5 nm by depositing 2-(3-(9,9-dimethyl-9H-fluoren-2-yl)-[1,1-biphenyl]-3-yl)-4,6-diphenyl-1,3,5-triazine on the emission layer.

[0506] Then, the electron transporting layer having a thickness of 31 nm is formed on the hole blocking layer by depositing 4-(4-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)naphthalen-1-yl)-[1,1-biphenyl]-4-carbonitrile and LiQ in a ratio of 50:50 vol.-%.

[0507] Then, an electron injection layer is formed having a thickness of 2 nm by depositing Yb onto the electron transport layer.

[0508] Then, Al is evaporated at a rate of 0.01 to 1 ?/s at 10?7 mbar to form a cathode layer with a thickness of 100 nm onto the electron injection layer.

[0509] The OLED stack is protected from ambient conditions by encapsulation of the device with a glass slide. Thereby, a cavity is formed, which includes a getter material for further protection.

[0510] To assess the performance of the inventive examples compared to the prior art, the current efficiency is measured at 20? C. The current-voltage characteristic is determined using a Keithley 2635 source measure unit, by sourcing a voltage in V and measuring the current in mA flowing through the device under test. The voltage applied to the device is varied in steps of 0.1V in the range between 0V and 10V. Likewise, the luminance-voltage characteristics and CIE coordinates are determined by measuring the luminance in cd/m.sup.2 using an Instrument Systems CAS-140CT array spectrometer (calibrated by Deutsche Akkreditierungsstelle (DAkkS)) for each of the voltage values. The cd/A efficiency at 10 mA/cm.sup.2 is determined by interpolating the luminance-voltage and current-voltage characteristics, respectively.

[0511] In bottom emission devices, the emission is predominately Lambertian and quantified in percent external quantum efficiency (EQE). The light is emitted through the anode layer. To determine the efficiency EQE in % the light output of the device is measured using a calibrated photodiode at 10 mA/cm2.

[0512] In top emission devices, the emission is forward directed through the cathode layer, non-Lambertian and also highly dependent on the mirco-cavity. Therefore, the efficiency EQE will be higher compared to bottom emission devices. To determine the efficiency EQE in % the light output of the device is measured using a calibrated photodiode at 10 mA/cm.sup.2.

[0513] Lifetime LT of the device is measured at ambient conditions (20? C.) and 30 mA/cm.sup.2, using a Keithley 2400 source meter, and recorded in hours.

[0514] The brightness of the device is measured using a calibrated photo diode. The lifetime LT is defined as the time till the brightness of the device is reduced to 97% of its initial value.

[0515] To determine the voltage stability over time U (100 h)-(1 h), a current density of at 30 mA/cm.sup.2 was applied to the device. The operating voltage was measured after 1 hour and after 100 hours, followed by calculation of the voltage stability for the time period of 1 hour to 100 hours. A low value for U (100 h)-(1 h) denotes a low increase in operating voltage over time and thereby improved voltage stability.

Technical Effect of the invention

[0516] In Table 1a are shown LUMO levels of compounds of formula (I) and comparative compound CC-7.

TABLE-US-00001 TABLE 1a Compound of formula (I) Example Name Chemical formula LUMO (eV) Comparative compound 7 CC-7 [00063] ?3.92 (?) Inventive compound 1 MC-1 [00064] ?4.55 (?) Inventive compound 2 MC-2 [00065] ?4.68 (?) Inventive compound 3 MC-3 [00066] ?3.92 (?) Inventive compound 4 MC-4 [00067] ?3.47 Inventive compound 5 MC-5 [00068] ?3.89 Inventive compound 6 MC-6 [00069] ?3.96 Inventive compound 7 MC-7 [00070] ?4.78 (?) Inventive compound 8 MC-8 [00071] ?5.03 (?) Inventive compound 9 MC-9 [00072] ?3.76 Inventive compound 10 MC-10 [00073] ?4.02 Inventive compound 11 MC-11 [00074] ?4.23 Inventive compound 12 MC-12 [00075] ?4.57 Inventive compound 13 MC-13 [00076] ?4.33 Inventive compound 14 MC-14 [00077] ?4.61

[0517] As can be seen in Table 1a, the LUMO levels of compounds of formula (I) are in a range similar to comparative compound CC-7, see MC-3 to MC-5 and MC-9, or further away from vacuum level compared to comparative compound CC-7, see MC-1, MC-2, MC-6 to MC-8 and MC-10 to MC-14.

[0518] Without being bound by theory, a LUMO level??3.9 eV may enable particularly efficient injection into adjacent layers comprising compounds with a HOMO level further away from vacuum level. In Table 1b are shown physical properties for inventive compounds 1 to 3 and comparative compounds 1 to 7.

[0519] As can be seen in Table 1b, thermal properties (T.sub.m, T.sub.dec, T.sub.subl, T.sub.RO) and/or the solubility in benzonitrile are improved over comparative examples.

Improved thermal properties may result in improved performance of organic electronic devices prepared via vacuum thermal evaporation.
Improved solubility in benzonitrile may result in improved manufacturing and/or performance of organic electronic devices prepared via deposition from solution.

[0520] In Table 2 are shown data for top emission organic electronic devices fabricated by co-deposition from vacuum of metal complex and matrix compound.

[0521] In comparative examples 1-1 to 1-4, two metal complexes known in the art are tested at two different doping concentrations.

[0522] As can be seen in Table 2, in comparative examples 1-1 to 1-4 the operating voltage is between 3.67 and 3.78 V, the external quantum efficiency EQE is between 12.9 and 13.91% and the voltage stability over time is between 0.85 and 1.28 V.

[0523] In inventive example 1-1, the semiconductor layer comprises a compound of formula (I) MC-1. MC-1 comprises a group R.sup.2 selected from CN. As can be seen in Table 2, the EQE is improved to 14.32% and operating voltage stability over time is improved to 0.46 V.

[0524] In inventive examples 1-2, the semiconductor layer comprises 15 vol.-% MC-1. As can be seen in Table 2, EQE and operating voltage stability over time remain improved over comparative examples 1-1 to 1-4.

[0525] In inventive examples 1-3 to 1-7, the semiconductor layer comprises compounds of formula (1) at a range of doping concentrations and matrix compounds with a range of HOMO levels. As can be seen in Table 2, EQE and operating voltage stability over time are improved over comparative examples 1-1 to 1-4.

[0526] In Table 3 are shown data for bottom emission organic electronic devices fabricated by co-deposition from solution of compound of formula (I) and a matrix compound.

[0527] As can be seen in Table 3, good performance of organic electronic devices is obtained.

[0528] A high efficiency and/or improved operating voltage stability over time are important for the performance and long-term stability of organic electronic devices.

TABLE-US-00002 TABLE 1 Properties of comparative compounds 1 to 7 and compounds of Formula (I) Sublimation Rate onset Solubility in temperature temperature benzonitrile Tm Tdec Tsubl T.sub.RO [mg/ml at Example Name Formula [? C.] [? C.] [? C.] [? C.] 20? C.] Comparative CC-1 Cu(acac)2 284 (dec) >280 110-120 <100 N.D..sup.1) compound 1 Comparative CC-2 Cu(tfac)2 201 >185 95-100 <100 N.D. compound 2 Comparative CC-3 Bi(tfac)3 131 >100 decomposition <100 N.D. compound 3 Comparative CC-4 Bi(hfac)3 N.D. N.D. decomposition <100 N.D. compound 4 Comparative CC-5 Bi(fod)3 Not obs. >200 120 <100 N.D. compound 5 Comparative CC-6 La(fod).sub.3 Not obs. >260 170 101 N.D. compound 6 Comparative compound 7 CC-7 [00078] 223 >300 245 170 <<10 Inventive compound 1 MC-1 [00079] 312 >319 261 204 N.D. Inventive compound 2 MC-2 [00080] 256 >330 decomposition N.D. >10 Inventive compound 3 MC-3 [00081] 302 >300 decomposition N.D. 10 mg/ml.sup.2) .sup.1)N.D. = not determined. .sup.2)at 60? C.

TABLE-US-00003 TABLE 2 Performance of an organic electronic device comprising a metal complex prepared via vacuum thermal evaporation Percentage metal Percentage matrix U(100 h) ? complex in HOMO level compound in U at 10 EQE at 10 U(1 h) Metal semiconductor Matrix of matrix semiconductor mA/cm.sup.2 mA/cm.sup.2 (30 mA/cm.sup.2) complex layer [vol.-%] compound compound [eV] layer [vol.-%] [V] [%] [V] Comparative CC-6 5 K1 ?4.68 95 3.67 12.99 0.85 example 1-1 Comparative CC-7 6 K1 ?4.68 94 3.8 13.91 1.24 example 1-2 Comparative CC-6 9 K1 ?4.68 91 3.65 12.90 0.89 example 1-3 Comparative CC-7 10 K1 ?4.68 90 3.78 13.81 1.28 example 1-4 Inventive MC-1 10 K1 ?4.68 90 3.75 14.32 0.46 example 1-1 Inventive MC-1 15 K1 ?4.68 85 3.73 14.36 0.47 example 1-2 Inventive MC-1 18 K16 ?4.73 82 3.81 15.42 0.07 example 1-3 Inventive MC-1 22 K16 ?4.73 78 3.8 15.44 0.06 example 1-4 Inventive MC-1 15 K2 ?4.85 85 3.75 14.73 0.06 example 1-5 Inventive MC-1 21 K2 ?4.85 79 3.74 14.72 0.03 example 1-6 Inventive MC-1 25 K2 ?4.85 75 3.73 14.71 0.02 example 1-7

TABLE-US-00004 TABLE 3 Performance of an device comprising a metal complex prepared via deposition from solution Percentage metal Percentage matrix complex in compound in U at 10 EQE at 10 Metal semiconductor Matrix semiconductor mA/cm.sup.2 mA/cm.sup.2 complex layer [vol.-%] compound layer [vol.-%] [V] [%] Inventive example 2-1 MC-2 10 K1 90 3.83 13.06 Inventive example 2-2 MC-3 10 K1 90 3.85 13.41

[0529] The particular combinations of elements and features in the above detailed embodiments are exemplary only; the interchanging and substitution of these teachings with other teachings in this and the patents/applications incorporated by reference are also expressly contemplated. As those skilled in the art will recognize, variations, modifications, and other implementations of what is described herein can occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention as claimed. Accordingly, the foregoing description is by way of example only and is not intended as limiting. In the claims, the word comprising does not exclude other elements or steps, and the indefinite article a or an does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. The invention's scope is defined in the following claims and the equivalents thereto. Furthermore, reference signs used in the description and claims do not limit the scope of the invention as claimed.