Organic Semiconductor Layer, Organic Electronic Device Comprising the Same and Compounds Therefor

Abstract

The present invention relates to an organic semiconductor layer and an organic electronic device comprising the same, wherein the organic electronic device comprises an anode, a cathode and at least one organic semiconductor layer, wherein the at least one organic semiconductor layer comprises: —a metal dopant, and —a compound represented by the following formula (I):

##STR00001##

Claims

1. Organic electronic device comprising an anode, a cathode and at least one organic semiconductor layer, wherein the at least one organic semiconductor layer comprises: a metal dopant, and a compound represented by the following formula (I): ##STR00144## wherein, Ar.sup.1 and Ar.sup.2 are same or different and independently selected from hydrogen, substituted or unsubstituted C.sub.6 to C.sub.36 aryl, substituted or unsubstituted C.sub.3 to C.sub.36 heteroaryl, wherein, at least one of the Ar.sup.1 and Ar.sup.2 group comprises a substituted or unsubstituted C.sub.3 to C.sub.36 heteroaryl; L is a single bond, a substituted or unsubstituted C.sub.6 to C.sub.18 arylene, a substituted or unsubstituted C.sub.3 to C.sub.18 heteroarylene; Ar.sup.3 is a substituted or unsubstituted heteroarylene selected from a substituted C.sub.4 N-heteroarylene, a substituted or unsubstituted C.sub.12 to C.sub.25 heteroarylene comprising at least three fused rings and one hetero atom selected from O, S or N, a substituted pyrazinylene, a substituted pyrimidinylene, a substituted or unsubstituted acridinylene, a substituted or unsubstituted benzoacridinylene, a substituted or unsubstituted dibenzoacridinylene, a substituted or unsubstituted dibenzofuranylene, a substituted or unsubstituted carbazolylene, a substituted or unsubstituted benzoquinolinylene, a substituted or unsubstituted phenanthridinylene, a substituted or unsubstituted dinaphthofuranylene or a substituted or unsubstituted dinaphthothiophenylene; Ar.sup.4 is a group independently selected from H, a substituted or unsubstituted C.sub.6 to C.sub.18 aryl, a substituted or unsubstituted C.sub.3 to C.sub.20 heteroaryl; n is 0, 1, 2, 3 or 4; wherein the substituents of L, Ar.sup.1, Ar.sup.2, Ar.sup.3, Ar.sup.4 and/or N are independently selected from: C.sub.6 to C.sub.18 aryl, C.sub.3 to C.sub.20 heteroaryl, C.sub.1 to C.sub.16 alkyl, C.sub.1 to C.sub.16 alkoxy, C.sub.3 to C.sub.16 branched alkyl, C.sub.3 to C.sub.16 cyclic alkyl, C.sub.3 to C.sub.16 branched alkoxy, C.sub.3 to C.sub.16 cyclic alkoxy, partially or perfluorinated C.sub.1 to C.sub.16 alkyl, partially or perfluorinated C.sub.1 to C.sub.16 alkoxy, partially or perdeuterated C.sub.1 to C.sub.16 alkyl, partially or perdeuterated C.sub.1 to C.sub.16 alkoxy, —PX.sup.3(R.sup.2).sub.2, D, F or CN; R.sup.1 and R.sup.2 are independently selected from C.sub.6 to C.sub.12 aryl, C.sub.3 to C.sub.12 heteroaryl, C.sub.1 to C.sub.16 alkyl, C.sub.1 to C.sub.16 alkoxy, partially or perfluorinated C.sub.1 to C.sub.16 alkyl, partially or perfluorinated C.sub.1 to C.sub.16 alkoxy, partially or perdeuterated C.sub.1 to C.sub.16 alkyl, partially or perdeuterated C.sub.1 to C.sub.16 alkoxy and two R.sup.1 can be linked together to form a ring X.sup.3 is selected from S or O.

2. The organic electronic device according to claim 1, wherein L is a substituted or unsubstituted C.sub.6 to C.sub.18 arylene or a substituted or unsubstituted C.sub.3 to C.sub.18 heteroarylene selected from: a substituted or unsubstituted phenylene, a substituted or unsubstituted biphenylene, a substituted or unsubstituted terphenylene, a substituted or unsubstituted anthracenylene, a substituted or unsubstituted dibenzofuranylene, a substituted or unsubstituted dibenzothiophenylene, a substituted or unsubstituted carbazolylene, a substituted or unsubstituted pyridinylene, a substituted or unsubstituted phenylpyridinylene, or a substituted or unsubstituted quinolinylene; wherein the substituents of L, Ar.sup.1, Ar.sup.2, Ar.sup.3, Ar.sup.4 and/or N are independently selected from: C.sub.6 to C.sub.18 aryl, C.sub.3 to C.sub.20 heteroaryl, C.sub.1 to C.sub.16 alkyl, C.sub.1 to C.sub.16 alkoxy, C.sub.3 to C.sub.16 branched alkyl, C.sub.3 to C.sub.16 cyclic alkyl, C.sub.3 to C.sub.16 branched alkoxy, C.sub.3 to C.sub.16 cyclic alkoxy, partially or perfluorinated C.sub.1 to C.sub.16 alkyl, partially or perfluorinated C.sub.1 to C.sub.16 alkoxy, partially or perdeuterated C.sub.1 to C.sub.16 alkyl, partially or perdeuterated C.sub.1 to C.sub.16 alkoxy, —PX.sup.3(R.sup.2).sub.2, D, F or CN; R.sup.1 and R.sup.2 are independently selected from C.sub.6 to C.sub.12 aryl, C.sub.3 to C.sub.12 heteroaryl, C.sub.1 to C.sub.16 alkyl, C.sub.1 to C.sub.16 alkoxy, partially or perfluorinated C.sub.1 to C.sub.16 alkyl, partially or perfluorinated C.sub.1 to C.sub.16 alkoxy, partially or perdeuterated C.sub.1 to C.sub.16 alkyl, partially or perdeuterated C.sub.1 to C.sub.16 alkoxy and two R.sup.1 can be linked together to form a ring X.sup.3 is selected from S or O.

3. The organic electronic device according to claim 1, wherein Ar.sup.4 is a substituted or unsubstituted C.sub.6 to C.sub.18 aryl or a substituted or unsubstituted C.sub.3 to C.sub.20 heteroaryl selected from: an unsubstituted phenyl, an unsubstituted biphenyl, an unsubstituted naphthyl, an unsubstituted anthracenyl, an unsubstituted phenanthridinyl, an unsubstituted pyridyl, an unsubstituted quinolinyl, an unsubstituted pryrimidyl, or having the formula (II) or (III), ##STR00145## wherein the group of formula (II) and (III) are substituted or unsubstituted and X.sup.2 is selected from NH, NR.sup.2, S, O, CH.sub.2, CHR.sup.2, CR.sup.1R.sup.2 or C(R.sup.2).sub.2; wherein the substituents of L, Ar.sup.1, Ar.sup.2, Ar.sup.3, Ar.sup.4 and/or N are independently selected from: C.sub.6 to C.sub.18 aryl, C.sub.3 to C.sub.20 heteroaryl, C.sub.1 to C.sub.16 alkyl, C.sub.1 to C.sub.16 alkoxy, C.sub.3 to C.sub.16 branched alkyl, C.sub.3 to C.sub.16 cyclic alkyl, C.sub.3 to C.sub.16 branched alkoxy, C.sub.3 to C.sub.16 cyclic alkoxy, partially or perfluorinated C.sub.1 to C.sub.16 alkyl, partially or perfluorinated C.sub.1 to C.sub.16 alkoxy, partially or perdeuterated C.sub.1 to C.sub.16 alkyl, partially or perdeuterated C.sub.1 to C.sub.16 alkoxy, —PX.sup.3(R.sup.2).sub.2, D, F or CN; R.sup.1 and R.sup.2 are independently selected from C.sub.6 to C.sub.12 aryl, C.sub.3 to C.sub.12 heteroaryl, C.sub.1 to C.sub.16 alkyl, C.sub.1 to C.sub.16 alkoxy, partially or perfluorinated C.sub.1 to C.sub.16 alkyl, partially or perfluorinated C.sub.1 to C.sub.16 alkoxy, partially or perdeuterated C.sub.1 to C.sub.16 alkyl, partially or perdeuterated C.sub.1 to C.sub.16 alkoxy and two R.sup.1 can be linked together to form a ring X.sup.3 is selected from S or O.

4. The organic electronic device according to claim 1, wherein Ar.sup.1 and Ar.sup.2 are independently selected from a hydrogen, phenyl, pyridyl, phenyl pyridyl or quinolinyl group.

5. The organic electronic device according to claim 1, wherein L is a single bond or is selected from an unsubstituted phenylene, an unsubstituted biphenylene, an unsubstituted terphenylene, an unsubstituted anthracenylene, an unsubstituted dibenzofuranylene, an unsubstituted dibenzothiophenylene, an unsubstituted an unsubstituted pyridinylene, a substituted or unsubstituted phenylpyridinylene.

6. The organic electronic device according to claim 1, wherein Ar.sup.3 is a group selected from a substituted pyrazinylene, a substituted pyrimidinylene, an unsubstituted benzoacridinylene or an unsubstituted dibenzoacridinylene.

7. The organic electronic device according to claim 1, wherein Ar.sup.4 is a group selected from H, an unsubstituted phenyl, an unsubstituted biphenyl, an unsubstituted pyridyl, an unsubstituted naphthyl, an unsubstituted dibenzofuranyl, an unsubstituted benzofuranyl, an unsubstituted dibenzothiophenyl, an unsubstituted benzothiophenyl.

8. The organic electronic device according to claim 1, wherein the metal dopant is a metal selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals Li, Na, Cs, Mg, Ca, Sr, Sm, and Yb.

9. The organic electronic device according to claim 1, wherein L is independently selected from B1 to B21: ##STR00146## ##STR00147## ##STR00148## wherein the asterisk symbol “*” represents the binding position of L.

10. The organic electronic device according to claim 1, wherein the metal of the metal dopant has an electronegativity of about ≥0.7 to about ≤1.3 according to Pauling scale.

11. An organic electronic device according to claim 1, wherein Ar.sup.3 is independently selected from E1 to E9: ##STR00149## ##STR00150## wherein the asterisk symbol “*” represents the binding position of Ar.sup.3 to L and if n=1, 2, 3 or 4 Ar.sup.4 bonds to a carbon of Ar.sup.3 excluding the binding position of Ar.sup.3 to L.

12. An organic electronic device according to claim 1, wherein Ar.sup.4 is independently selected from hydrogen or F1 to F13: ##STR00151## ##STR00152## wherein the asterisk symbol “*” represents the binding position of Ar.sup.4 to Ar.sup.3, and Ar.sup.4 bonds to a carbon of Ar.sup.3 excluding the binding position of Ar.sup.3 to L.

13. The organic electronic device according to claim 1, wherein the compound of formula (I) are selected from G1 to G36: ##STR00153## ##STR00154## ##STR00155## ##STR00156## ##STR00157## ##STR00158## ##STR00159## ##STR00160## ##STR00161## ##STR00162## ##STR00163## ##STR00164##

14. The organic electronic device according to claim 1, wherein the organic electronic device further comprises at least one emission layer and the organic semiconductor layer is arranged between the at least one emission layer and the cathode.

15. The organic electronic device according to claim 1, wherein the electronic device is a light emitting device, thin film transistor, a battery, a display device, or a photovoltaic cell.

16. A compound represented by the following formula (I): ##STR00165## wherein, Ar.sup.1 and Ar.sup.2 are same or different and independently selected from hydrogen, substituted or unsubstituted C.sub.6 to C.sub.36 aryl, substituted or unsubstituted C.sub.3 to C.sub.36 heteroaryl, wherein, at least one of the Ar.sup.1 and Ar.sup.2 group comprises a substituted or unsubstituted C.sub.3 to C.sub.36 heteroaryl; L is a single bond, a substituted or unsubstituted C.sub.6 to C.sub.18 arylene, a substituted or unsubstituted C.sub.3 to C.sub.18 heteroarylene; Ar.sup.3 is a substituted or unsubstituted heteroarylene selected from substituted pyrazinylene, substituted or unsubstituted dibenzoacridinylene; Ar.sup.4 is a group independently selected from H, a substituted or unsubstituted C.sub.6 to C.sub.18 aryl, a substituted or unsubstituted C.sub.3 to C.sub.20 heteroaryl, preferably the substituted or unsubstituted C.sub.6 to C.sub.18 aryl or the substituted or unsubstituted C.sub.3 to C.sub.20 heteroaryl is selected from an unsubstituted phenyl, an unsubstituted biphenyl, an unsubstituted naphthyl, unsubstituted anthracenyl, an unsubstituted phenanthridinyl, an unsubstituted pyridyl, an unsubstituted quinolinyl, an unsubstituted pryrimidyl, or having the formula (II) or (III), ##STR00166## wherein the group of formula (II) and (III) are substituted or unsubstituted and X.sup.2 is selected from NH, NR.sup.2, S, O, CH.sub.2, CHR.sup.2, CR.sup.1R.sup.2 or C(R.sup.2).sub.2; n is 0, 1, 2, 3 or 4; wherein the substituents of L, Ar.sup.1, Ar.sup.2, Ar.sup.3, Ar.sup.4 and/or N are independently selected from: C.sub.6 to C.sub.18 aryl, C.sub.3 to C.sub.20 heteroaryl, C.sub.1 to C.sub.16 alkyl, C.sub.1 to C.sub.16 alkoxy, C.sub.3 to C.sub.16 branched alkyl, C.sub.3 to C.sub.16 cyclic alkyl, C.sub.3 to C.sub.16 branched alkoxy, C.sub.3 to C.sub.16 cyclic alkoxy, partially or perfluorinated C.sub.1 to C.sub.16 alkyl, partially or perfluorinated C.sub.1 to C.sub.16 alkoxy, partially or perdeuterated C.sub.1 to C.sub.16 alkyl, partially or perdeuterated C.sub.1 to C.sub.16 alkoxy, —PX.sup.3(R.sup.2).sub.2, D, F or CN; R.sup.1 and R.sup.2 are independently selected from C.sub.6 to C.sub.12 aryl, C.sub.3 to C.sub.12 heteroaryl, C.sub.1 to C.sub.16 alkyl, C.sub.1 to C.sub.16 alkoxy, partially or perfluorinated C.sub.1 to C.sub.16 alkyl, partially or perfluorinated C.sub.1 to C.sub.16 alkoxy, partially or perdeuterated C.sub.1 to C.sub.16 alkyl, partially or perdeuterated C.sub.1 to C.sub.16 alkoxy and two R.sup.1 can be linked together to form a ring X.sup.3 is selected from S or O.

17. Compound according to claim 16, wherein L is selected from an unsubstituted phenylene or an unsubstituted biphenylene.

18. The organic electronic device according to claim 1, wherein the metal of the metal dopant has an electronegativity of about ≥0.9 to about ≤1.2 according to Pauling scale.

19. The organic electronic device according to claim 1, wherein the metal of the metal dopant has an electronegativity of about ≥1 to about ≤1.1 according to Pauling scale.

20. The organic electronic device according to claim 14 wherein the electronic device is a light emitting device, thin film transistor, a battery, a display device, or a photovoltaic cell.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0557] These and/or other aspects and advantages of the present invention will become apparent and more readily appreciated from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawings, of which:

[0558] FIG. 1 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention;

[0559] FIG. 2 is a schematic sectional view of an OLED, according to an exemplary embodiment of the present invention.

[0560] FIG. 3 is a schematic sectional view of a tandem OLED comprising a charge generation layer, according to an exemplary embodiment of the present invention.

[0561] FIG. 4 is a schematic sectional view of a tandem OLED comprising a charge generation layer, according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION

[0562] Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The exemplary embodiments are described below, in order to explain the aspects of the present invention, by referring to the figures.

[0563] Herein, when a first element is referred to as being formed or disposed “on” a second element, the first element can be disposed directly on the second element, or one or more other elements may be disposed there between. When a first element is referred to as being formed or disposed “directly on” a second element, no other elements are disposed there between.

[0564] FIG. 1 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 120, a hole injection layer (HIL) 130, a hole transport layer (HTL) 140, an emission layer (EML) 150, an electron transport layer (ETL) 160, an electron injection layer (EIL) 180 and a cathode 190. The electron transport layer (ETL) 160 comprises or consists of the compound of Formula (I) and a metal dopant.

[0565] Instead of a single electron transport layer 160, optional an electron transport layer stack (ETL) can be used. The electron transport layer stack (ETL) comprises a first electron transport layer and a second electron transport layer, wherein the first electron transport layer is arranged near to EML and the second electron transport layer is arranged near to the cathode (190). The first and/or the second electron transport layer comprise the compound of Formula (I) and a metal dopant according to the invention.

[0566] FIG. 2 is a schematic sectional view of an OLED 100, according to another exemplary embodiment of the present invention. FIG. 2 differs from FIG. 1 in that the OLED 100 of FIG. 2 comprises an electron blocking layer (EBL) 145 and a hole blocking layer (HBL) 155. Referring to FIG. 2 the OLED 100 includes a substrate 110, an anode 120, a hole injection layer (HIL) 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 electron injection layer (EIL) 180 and a cathode electrode 190. The electron transport layer (ETL) 160 and/or the electron injection layer (EIL) 180 comprise or consist of the compound of Formula (I) and metal dopant.

[0567] In the description above the method of manufacture an OLED 100 of the present invention is started with a substrate 110 onto which an anode 120 is formed, on the anode electrode 120, an hole injection layer 130, hole transport layer 140, optional an electron blocking layer 145, an emission layer 150, optional a hole blocking layer 155, optional at least one electron transport layer 160, optional at least one electron injection layer 180, and a cathode 190 are formed, in that order or the other way around.

[0568] FIG. 3 is a schematic sectional view of an OLED 200, according to another exemplary embodiment of the present invention. FIG. 3 differs from FIG. 2 in that the OLED 100 of FIG. 3 further comprises a charge generation layer and a second hole transport layer (HTL) 141. Referring to FIG. 3 the OLED 200 includes a substrate 110, an anode 120, a first hole injection layer (HIL) 130, a first hole transport layer (HTL) 140, a first electron blocking layer (EBL) 145, a first emission layer (EML) 150, a first hole blocking layer (HBL) 155, a first electron transport layer (ETL) 160, an n-type charge generation layer (n-type CGL) 185 which may comprise compound of Formula (I) and a metal dopant, a p-type charge generation layer (p-type GCL) 135, a second hole transport layer (HTL) 141 and a cathode 190. The electron transport layers (ETL) 160 and 161 and/or the electron injection layer (EIL) 180 and/or the n-type charge generation layer (n-type CGL) 185 comprise or consist of the compound of Formula (I) and a metal dopant.

[0569] FIG. 4 is a schematic sectional view of a tandem OLED 200, according to another exemplary embodiment of the present invention. FIG. 4 differs from FIG. 2 in that the OLED 100 of FIG. 3 further comprises a charge generation layer and a second emission layer. Referring to FIG. 4 the OLED 200 includes a substrate 110, an anode 120, a first hole injection layer (HIL) 130, a first hole transport layer (HTL) 140, a first electron blocking layer (EBL) 145, a first emission layer (EML) 150, a first hole blocking layer (HBL) 155, a first electron transport layer (ETL) 160, an n-type charge generation layer (n-type CGL) 185 which may comprise compound of Formula (I) and a metal dopant, a p-type charge generation layer (p-type GCL) 135, a second hole transport layer (HTL) 141, a second electron blocking layer (EBL) 146, a second emission layer (EML) 151, a second hole blocking layer (EBL) 156, a second electron transport layer (ETL) 161, a second electron injection layer (EIL) 181 and a cathode 190. The electron transport layers (ETL) 160 and 161 and/or the electron injection layer (EIL) 180 and/or the n-type charge generation layer (n-type CGL) 185 comprise or consist of the compound of Formula (I) and a metal dopant.

[0570] In the description above the method of manufacture an OLED 200 of the present invention is started with a substrate 110 onto which an anode 120 is formed, on the anode electrode 120, a first hole injection layer 130, first hole transport layer 140, optional a first electron blocking layer 145, a first emission layer 150, optional a first hole blocking layer 155, optional at least one first electron transport layer 160, an n-type CGL 185, a p-type CGL 135, a second hole transport layer 141, optional a second electron blocking layer 146, a second emission layer 151, an optional second hole blocking layer 156, an optional at least one second electron transport layer 161, an optional a second electron injection layer (EIL) 181 and a cathode 190 are formed, in that order or the other way around.

EMBODIMENTS

[0571] Hereinafter, the embodiments are illustrated in more detail with reference to examples. However, the present disclosure is not limited to the following examples. Reference will now be made in detail to the exemplary aspects.

Preparation of Compounds of Formula (I)

General Procedure 1 for the Synthesis of Compound of Formula (I)

[0572] ##STR00095##

[0573] To synthesize compound of Formula (I) a flask was flushed with nitrogen and charged with reagent 1 (1.1 equiv.), reagent 2 (1 equiv.), K.sub.2CO.sub.3 (2 equiv.) dissolved in deaerated water), [1,1′-Bis(diphenylphosphino)ferrocene]dichloropalladium(II) (2 mol %). A deaerated mixture of toluene and ethanol (5:1) was added and the reaction mixture was heated to reflux under a nitrogen atmosphere while monitoring with TLC. After cooling down to room temperature, the resulting precipitate was isolated by suction filtration and washed with water (100 mL) and methanol (30 mL). For further purification the crude product was then dissolved in dichloromethane and filtered through a pad of silicagel. After rinsing with additional dichloromethane, the filtrate was concentrated under reduced pressure and precipitated from methanol (150 mL). The resulting precipitate was recrystallized from 100 mL toluene. The formed precipitate was collected by suction filtration and washed with small portion of toluene to give compound of Formula (I). An additional crop is isolated by precipitation by concentration of the toluene mother liquor Final purification was achieved by sublimation.

General Procedure 2 for the Synthesis of Compound of Formula (I)

[0574] ##STR00096##

[0575] To synthesize compound of Formula (I) a flask was flushed with nitrogen and charged with reagent (1) (1.1 equiv.), 4′-chloro-2,2′:6′,2″-terpyridine (2) (1 equiv.), K.sub.2CO.sub.3 (2 equiv.) dissolved in deaerated water), [1,1′-Bis(diphenylphosphino)ferrocene]dichloropalladium(II) (2 mol %). A deaerated mixture of toluene and ethanol (5:1) was added and the reaction mixture was heated to reflux under a nitrogen atmosphere while monitoring with TLC. After cooling down to room temperature, the resulting precipitate was isolated by suction filtration and washed with water (100 mL) and methanol (30 mL). For further purification the crude product was then dissolved in dichloromethane and filtered through a pad of silicagel. After rinsing with additional dichloromethane, the filtrate was concentrated under reduced pressure and precipitated from methanol (150 mL). The resulting precipitate was recrystallized from 100 mL toluene. The formed precipitate was collected by suction filtration and washed with small portion of toluene to give compound of Formula (I). An additional crop is isolated by precipitation by concentration of the toluene mother liquor Final purification was achieved by sublimation.

General Procedure 3 for the Synthesis of Compound of Formula (I)

[0576] ##STR00097##

[0577] To synthesize compound of Formula (I) a flask was flushed with nitrogen and charged with reagent (1) (1.1 equiv.), Reagent 2 (1 equiv.), K.sub.2CO.sub.3 (2 equiv.) dissolved in deaerated water), [1,1′-Bis(diphenylphosphino)ferrocene]dichloropalladium(II) (2 mol %). A deaerated mixture of toluene and ethanol (5:1) was added and the reaction mixture was heated to reflux under a nitrogen atmosphere while monitoring with TLC. After cooling down to room temperature, the resulting precipitate was isolated by suction filtration and washed with water (100 mL) and methanol (30 mL). For further purification the crude product was then dissolved in dichloromethane and filtered through a pad of silicagel. After rinsing with additional dichloromethane, the filtrate was concentrated under reduced pressure and precipitated from methanol (150 mL). The resulting precipitate was recrystallized from 100 mL toluene. The formed precipitate was collected by suction filtration and washed with small portion of toluene to give compound of Formula (I). An additional crop is isolated by precipitation by concentration of the toluene mother liquor Final purification was achieved by sublimation.

General Procedure 4 for the Synthesis of Compound of Formula (I)

[0578] ##STR00098##

[0579] To synthesize compound of Formula (I) a flask was flushed with nitrogen and charged with reagent (1) (1.1 equiv.), Reagent 2 (1 equiv.), K.sub.2CO.sub.3 (2 equiv.) dissolved in deaerated water), [1,1′-Bis(diphenylphosphino)ferrocene]dichloropalladium(II) (2 mol %). A deaerated mixture of toluene and ethanol (5:1) was added and the reaction mixture was heated to reflux under a nitrogen atmosphere while monitoring with TLC. After cooling down to room temperature, the resulting precipitate was isolated by suction filtration and washed with water (100 mL) and methanol (30 mL). For further purification the crude product was then dissolved in dichloromethane and filtered through a pad of silicagel. After rinsing with additional dichloromethane, the filtrate was concentrated under reduced pressure and precipitated from methanol (150 mL). The resulting precipitate was recrystallized from 100 mL toluene. The formed precipitate was collected by suction filtration and washed with small portion of toluene to give compound of Formula (I). An additional crop is isolated by precipitation by concentration of the toluene mother liquor Final purification was achieved by sublimation.

Building Block Preparation

Synthesis of 2,3,5-triphenyl-6-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)pyrazine

[0580] ##STR00099##

[0581] A flask was flushed with nitrogen and charged with 2-(4-bromophenyl)-3,5,6-triphenylpyrazine (15.0 g, 32.4 mmol), bis(pinacolato)diboron (9.04 g, 35.6 mmol), Pd(dppf)Cl2 (0.71 g, 0.97 mmol), and potassium acetate (9.5 g, 97.2 mmol). Dry and deaerated DMF (90 mL) was added and the reaction mixture was heated to 100° C. under a nitrogen atmosphere overnight. Subsequently, all volatiles were removed in vacuo, water (400 mL) and dichloromethane (1 L) were added and the organic phase was washed with water (3×400 mL). After drying over MgSO4, the organic phase was filtered through a pad of silica gel. After rinsing with additional dichloromethane (1 L), the filtrate was concentrated under reduced pressure to a minimal volume. Methanol (350 mL) was added and the suspension was left stirring at room temperature overnight. The solid was collected by suction filtration to yield 15.9 g (96%) of 2,3,5-triphenyl-6-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)pyrazine after drying.

Synthesis of 2,3,5-triphenyl-6-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)pyrazine

[0582] ##STR00100##

[0583] A flask was charged with 1-(3-bromophenyl)-2-phenylethane-1,2-dione (36.6 g, 126.5 mmol), 1,2-diphenylethane-1,2-diamine (38.7 g, 182.1 mmol), and acetic acid (320) mL. The mixture was heated to 75° C. for 24 h. Subsequently, the reaction mixture was concentrated under reduced pressure to approx. 100 mL and then carefully poured into sat. aq. K.sub.2CO.sub.3 (700 mL). After extraction with dichloromethane three times, the combined organic phases were washed with brine, dried over MgSO4, and concentrated under reduced pressure. The crude product was purified by column chromatography (silica, n-hexane/dichloromethane 8:2) and trituration with n-hexane to afford 38.8 g (66%) of 2,3,5-triphenyl-6-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)pyrazineafter drying.

Representative Synthesis of 4′-(3-(3,5,6-triphenylpyrazin-2-yl)phenyl)-2,2′:6′,2″-terpyridine

[0584] ##STR00101##

[0585] To synthesize 4′-(3-(3,5,6-triphenylpyrazin-2-yl)phenyl)-2,2′:6′,2″-terpyridine (compound MX2) a flask was flushed with nitrogen and charged with 2,3,5-triphenyl-6-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)pyrazine (1) (17.0 g, 33.0 mmol), 4′-chloro-2,2′:6′,2″-terpyridine (2) (8.1 g, 30.0 mmol), K.sub.2CO.sub.3 (8.29 g, 60 mmol, dissolved in 30 mL deaerated water), [1,1′-Bis(diphenylphosphino)ferrocene]dichloropalladium(II) (0.44 g, 0.6 mmol). A deaerated mixture of toluene and ethanol (5:1, 180 mL) was added and the reaction mixture was heated to reflux under a nitrogen atmosphere while monitoring with TLC. After cooling down to room temperature, the resulting precipitate was isolated by suction filtration and washed with water (100 mL) and methanol (30 mL). For further purification the crude product was then dissolved in dichloromethane and filtered through a pad of silicagel. After rinsing with additional dichloromethane, the filtrate was concentrated under reduced pressure and precipitated from methanol (150 mL). The resulting precipitate was recrystallized from 100 mL toluene. The formed precipitate was collected by suction filtration and washed with small portion of toluene to give 7.8 g of compound 1. An additional crop is isolated by precipitation by concentration of the toluene mother liquor. Combined 11.6 g of Compound G18 were obtained after drying. Final purification was achieved by sublimation. HPLC: 99.96%, m/z=616 ([M+H]+).

Synthesis of 7-(3-([2,2′-bipyridin]-6-yl)phenyl)dibenzo[c,h]acridine

[0586] ##STR00102##

[0587] To synthesize 7-(3-([2,2′-bipyridin]-6-yl)phenyl)dibenzo[c,h]acridine (compound 1) a flask was flushed with nitrogen and charged with 7-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)dibenzo[c,h]acridine (30 g, 62.3 mmol), 6-bromo-2,2′-bipyridine (16.1 g, 68.5 mmol), K3PO4 (31.8 g, 150 mmol, dissolved in 75 mL deaerated water), chloro(crotyl)(2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl)palladium(II) (0.76 g, 1.24 mmol). Deaerated THF (310 mL) was added and the reaction mixture was heated to 60° C. under a nitrogen atmosphere while monitoring with TLC. After cooling down to room temperature the solvent was distilled of. The resulting solid was extracted with CHCl3/H2O. The CHCl3 solution was dried over MgSO4 and filtered through a pad of florisil, additional rinsing is done with THF. The THF-solution is concentrated under reduced pressure. The precipitate is collected by suction filtration. After drying 12.5 g of G11 were obtained. Final purification was achieved by sublimation. HPLC 100%; m/z=510.2 ([M+H]+).

[0588] Further examples (compound G1-G3 and G12) were obtained by following this exemplary protocol, varying reagent 1, using the reagents and conditions and purification adaption as given in the Table 1 below:

TABLE-US-00001 TABLE 1 Solvent Amount (Yield) Compund Regent 1 Catalyst Base Temp. Further purification method HPLC [00103] [00104] 1798781-99-3 7778-53-2 THF/H2O 7/2 60° C. product precipitates, crude treated with Pd(dba)2/PtBu3 in Xylene at reflux for 24h, then filtered through SiO2, rinse CH2Cl2/MeOH, organic phase concentrated & precip. 7,1 g (58%) 100% m/z = 562 [M + H].sup.+ [00105] [00106] 1798781-99-3 7778-53-2 THF/H2O 4/1 60° C. product precipitates, soxhlet extraction (chlorobenzene), crystallization from chlorobenzene 18,2 g (67%) 100% m/z = 587 [M + H].sup.+ [00107] [00108] 1798781-99-3 7778-53-2 THF/H2O 4/1 60° C. product precipitates, soxhlet extraction (chlorobenzene), crystallization from chlorobenzene 8,5 g (63%) 100% m/z = 587 [M + H].sup.+ [00109] [00110] 1798781-99-3 7778-53-2 dioxane/H2O 10/1 60° C. product precipitates, filtration through SiO2 (CHCl3), concentrated and precipitation with iso-propylacetate 30 g (84%) 100% m/z = 616 [M + H].sup.+

[0589] In Table 2 below the properties of inventive compounds of Formula (I) are listed.

TABLE-US-00002 TABLE 2 Properties of inventive compounds of Formula (1) Diplole Tg Tro HOMO LUMO moment Referred to as: Structure mp (° C.) (° C.) (° C.) (eV) (eV) (Debye) G1 [00111] 287 148 250 −5.70 −1.79 0.47 G2 [00112] 343 156 — −5.66 −1.82 2.03 G3 [00113] 339 156 288 −5.60 −2.02 4.0 G11 [00114] 236 109 208 −5.48 −1.59 — G12 [00115] 280 131 238 −5.79 −1.71 1.91 G18 [00116] — 118 225 −5.64 −1.64 1.61
General procedure 1 the for Fabrication of OLEDs

[0590] For bottom emission devices, Examples 1 to 4 and comparative examples 1 to 2, a glass substrate was cut to a size of 150 mm×150 mm×0.7 mm, ultrasonically cleaned with isopropyl alcohol for 5 minutes and then with pure water for 5 minutes, and cleaned again with UV ozone for 30 minutes, to prepare a first electrode. 90 nm ITO were deposited on the glass substrate at a pressure of 10.sup.−5 to 10.sup.−7 mbar to form the anode.

[0591] Then, 92 vol.-% Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine (CAS 1242056-42-3) with 8 vol.-% 2,2′,2″-(cyclopropane-1,2,3-triylidene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) was vacuum deposited on the anode, to form a HIL having a thickness of 10 nm.

[0592] 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 HTL having a thickness of 128 nm.

[0593] Then N,N-bis(4-(dibenzo[b,d]furan-4-yl)phenyl)-[1,1′:4′,1″-terphenyl]-4-amine (CAS 1198399-61-9) was vacuum deposited on the HTL, to form an electron blocking layer (EBL) having a thickness of 5 nm.

[0594] Then 97 vol.-% H09 (Sun Fine Chemicals, South Korea) as EML host and 3 vol.-% BD200 (Sun Fine Chemicals, South Korea) as fluorescent blue dopant were deposited on the EBL, to form a blue-emitting EML with a thickness of 20 nm.

[0595] Then the 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.

[0596] Then, the electron transporting layer is formed on the hole blocking layer according to Examples 1 to 4 and comparative examples 1 to 2 with a the thickness of 31 nm. The electron transport layer comprises 99 wt.-% matrix compound of Formula 1 and 1 wt.-% of Li as metal dopant or electron transport layer comprises 97 wt.-% matrix compound of Formula 1 and 3 wt.-% of Yb, see Table 3.

[0597] Al is evaporated at a rate of 0.01 to 1 Å/s at 10.sup.−7 mbar to form a cathode with a thickness of 100 nm.

[0598] 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 Procedure 2 for the Fabrication of OLEDs

[0599] For bottom emission devices, Examples 4 to 8 and comparative examples 3 to 5, a glass substrate was cut to a size of 150 mm×150 mm×0.7 mm, ultrasonically cleaned with isopropyl alcohol for 5 minutes and then with pure water for 5 minutes, and cleaned again with UV ozone for 30 minutes, to prepare a first electrode. 90 nm ITO were deposited on the glass substrate at a pressure of 10.sup.−5 to 10.sup.−7 mbar to form the anode.

[0600] Then, 97 vol.-% Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine (CAS 1242056-42-3) with 3 vol.-% 2,2′,2″-(cyclopropane-1,2,3-triylidene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) was vacuum deposited on the anode, to form a HIL having a thickness of 10 nm.

[0601] 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 128 nm.

[0602] Then N,N-bis(4-(dibenzo[b,d]furan-4-yl)phenyl)-[1,1′:4′,1″-terphenyl]-4-amine (CAS 1198399-61-9) was vacuum deposited on the HTL, to form an electron blocking layer (EBL) having a thickness of 5 nm.

[0603] Then 97 vol.-% H09 (Sun Fine Chemicals, South Korea) as EML host and 3 vol.-% BD200 (Sun Fine Chemicals, South Korea) as fluorescent blue dopant were deposited on the EBL, to form a first blue-emitting EML with a thickness of 20 nm.

[0604] Then the first 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.

[0605] Then, the electron transporting layer having a thickness of 25 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. The electron transport layer (ETL) comprises 50 wt.-% matrix compound and 50 wt.-% of LiQ.

[0606] Then the n-CGL was formed on ETL with a thickness of 15 nm. The n-CGL comprises 99 wt.-% matrix compound of Formula 1 and 1 wt.-% of Li as metal dopant or electron transport layer comprises 97 wt.-% matrix compound of Formula 1 and 3 wt.-% of Yb, see Table 4. Then the p-CGL was formed on n-CGL with a thickness of 10 nm on n-CGL by depositing Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl) -[4-(9-phenyl-9H-carbazol-3-yl) phenyl]-amine.

[0607] 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 p-CGL, to form a second HTL having a thickness of 10 nm.

[0608] Al is evaporated at a rate of 0.01 to 1 Å/s at 10.sup.−7 mbar to form a cathode with a thickness of 100 nm.

[0609] 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.

[0610] 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.

[0611] Lifetime LT of the device is measured at ambient conditions (20° C.) and 30 mA/cm.sup.2, using a Keithley 2400 sourcemeter, and recorded in hours.

[0612] 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.

[0613] In Table 3 is shown the performance of an organic electronic device comprising an electron transport layer comprising a compound of Formula (I) and a metal dopant.

[0614] In comparative example 1, compound ETM-1 was used as matrix compound:

##STR00117##

[0615] Compound ETM-1 is free of a terpyridyl-group. The organic semiconductor layer comprises 99 vol.-% ETM-1 and 1 vol.-% Li. The operating voltage at 15 mA/cm.sup.2 is 8.4 V and the cd/A efficiency is 3.3 cd/A.

[0616] In comparative example 2, compound ETM-1 was used as matrix compound:

##STR00118##

[0617] Compound ETM-1 is free of a terpyridyl-group. The ETL comprises 97 vol.-% ETM-2 and 3 vol.-% Yb. The operating voltage at 15 mA/cm.sup.2 is 6.3 V and the cd/A efficiency is 3.0 cd/A.

[0618] In Example 1, the ETL comprises 99 vol.-% compound of Formula (I) of G1

##STR00119##

and 1 vol.-% Li. The operating voltage at 15 mA/cm.sup.2 is 3.7 V and the cd/A efficiency is 8.5 cd/A.

[0619] In Example 2, the ETL comprises 97 vol.-% compound of Formula (I) of G1

##STR00120##

and 3 vol.-% Yb. The operating voltage at 15 mA/cm.sup.2 is 4.6 V and the cd/A efficiency is 4.8 cd/A.

[0620] In Example 3, the ETL comprises 99 vol.-% compound of Formula (I) of MX2

##STR00121##

and 1 vol.-% Li. The operating voltage at 15 mA/cm.sup.2 is 3.8 V and the cd/A efficiency is 7.8 cd/A.

[0621] In Example 4, the ETL comprises 97 vol.-% compound of Formula (I) of G12

##STR00122##

and 3 vol.-% Yb. The operating voltage at 15 mA/cm.sup.2 is 4.6 V and the cd/A efficiency is 4.5 cd/A.

[0622] In Table 3 it is shown the performance of an organic electronic device comprising an n-CGL comprising a compound of Formula (I) and a metal dopant.

[0623] In comparative example 3, compound ETM-1 was used as matrix compound:

##STR00123##

[0624] Compound ETM-1 is free of a terpyridyl-group. The n-CGL comprises 99 vol.-% ETM-1 and 1 vol.-% Li. The operating voltage at 15 mA/cm.sup.2 is 8.4 V and the cd/A efficiency is -cd/A.

[0625] In comparative example 4, compound ETM-2 was used as matrix compound:

##STR00124##

[0626] Compound ETM-2 is free of a terpyridyl-group. The n-CGL comprises 99 vol.-% ETM-1 and 1 vol.-% Li. The operating voltage at 15 mA/cm.sup.2 is 8.4 V and the cd/A efficiency is -cd/A.

[0627] In comparative example 5, compound ETM-2 was used as matrix compound:

##STR00125##

[0628] Compound ETM-2 is free of a terpyridyl-group. The n-CGL comprises 97 vol.-% ETM-2 and 3 vol.-% Yb. The operating voltage at 15 mA/cm.sup.2 is 6.3 V and the cd/A efficiency is 7.3 cd/A.

[0629] In comparative example 5, compound ETM-1 was used as matrix compound:

##STR00126##

[0630] Compound ETM-1 is free of a terpyridyl-group. The ETL comprises 97 vol.-% ETM-2 and 3 vol.-% Yb. The operating voltage at 15 mA/cm.sup.2 is 6.3 V and the cd/A efficiency is 3.0 cd/A.

[0631] In Example 5, the n-CGL comprises 99 vol.-% compound of Formula (I) of G1

##STR00127##

and 1 vol.-% Li. The operating voltage at 15 mA/cm.sup.2 is 5.2 V and the cd/A efficiency is 6.8 cd/A.

[0632] In Example 6, the n-CGL comprises 97 vol.-% compound of Formula (I) of G1

##STR00128##

and 3 vol.-% Yb. The operating voltage at 15 mA/cm.sup.2 is 5.1 V and the cd/A efficiency is 6.7 cd/A.

[0633] In Example 7, the n-CGL comprises 99 vol.-% compound of Formula (I) of G12

##STR00129##

and 1 vol.-% Li. The operating voltage at 15 mA/cm.sup.2 is 5.2 V and the cd/A efficiency is 6.8 cd/A.

[0634] In Example 8, the n-CGL comprises 97 vol.-% compound of Formula (I) of G12

##STR00130##

and 3 vol.-% Yb. The operating voltage at 15 mA/cm.sup.2 is 5.1 V and the cd/A efficiency is 6.9 cd/A.

[0635] Therefore, it can be seen the material for ETL (Example 1-4) and n-CGL (Example 5-8) can secure low driving voltage and high efficiency of an organic electronic device, when used in an organic electronic device.

TABLE-US-00003 TABLE 3 Performance of an organic electronic device comprising an electron transport layer comprising a compound of Formula (1) and a metal dopant Con- Con- Thickness Operating centration centration electron voltage of matrix of Metal transport at 15 compound in Metal dopant layer mA/cm.sup.2 Example Matrix compound ETL (vol.-%) dopant (vol.-%) (nm) (V) Example 1 (Comparative) [00131] 99 Li 1 31 8.4 Example 2 (Comparative) [00132] 97 Yb 3 31 6.3 Example 1 [00133] 99 Li 1 31 3.7 Example 2 [00134] 97 Yb 3 31 4.6 Example 3 [00135] 99 Li 1 31 3.8 Example 4 [00136] 97 Yb 3 31 4.6

TABLE-US-00004 TABLE 4 Performance of an organic electronic device comprising an n-CGL comprising a compound of Formula (1) and a metal dopant Concentration Thickness Operating n-CGL Metal of Metal n-CGL voltage at 15 Example Matrix compound (vol.-%) dopant dopant (vol.-%) (nm) mA/cm.sup.2 (V) Example 3 Comparative [00137] 99 Li 1 15 11.9 Example 4 Comparative [00138] 99 Li 1 15 10.4 Example 5 Comparative [00139] 97 Yb 3 15  9.8 Example 5 [00140] 99 Li 1 15  5.2 Example 6 [00141] 97 Yb 3 15  5.1 Example 7 [00142] 99 Li 1 15  5.2 Example 8 [00143] 97 Yb 3 15  5.1

[0636] In summary, low operating voltage and improved lifetime may be achieved when the organic semiconductor layer comprises a compound of Formula (I) and metal dopant.

[0637] While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Therefore, the aforementioned embodiments should be understood to be exemplary but not limiting the present invention in any way.