Organic electronic device comprising an organic semiconductor layer

Abstract

The present invention relates to a compound of formula 1 and an organic electronic device comprising an organic semiconductor layer, wherein at least one organic semiconductor layer comprises a compound of formula (1), wherein L.sup.1 has the formula (2) and L.sup.2 has the formula (3), wherein L.sup.1 and L.sup.2 are bonded at “*” via a single bond independently to the same or different arylene groups or heteroarylenes group of Ar.sup.1; and wherein X.sup.1, X.sup.2 are independently selected from O, S and Se; Ar.sup.1 is selected from substituted or unsubstituted C.sub.20 to C.sub.52 arylene or C.sub.14 to C.sub.64 heteroarylene, wherein the substituent of the substituted C.sub.20 to C.sub.52 arylene or C.sub.14 to C.sub.64 heteroarylene are independently selected from C.sub.1 to C.sub.12 alkyl, C.sub.1 to C.sub.12 alkoxy, CN, halogen, OH, C.sub.6 to C.sub.25 aryl and C.sub.2 to C.sub.21 heteroaryl; R.sup.1, R.sup.2 are independently selected from substituted or unsubstituted C.sub.1 to C.sub.16 alkyl, wherein the substituent of substituted C.sub.1 to C.sub.16 alkyl is selected from C.sub.6 to C.sub.18 arylene or C.sub.2 to C.sub.12 heteroarylene; R.sup.3, R.sup.4 are independently selected from substituted or unsubstituted C.sub.1 to C.sub.16 alkyl, substituted or unsubstituted C.sub.6 to C.sub.18 arylene, C.sub.2 to C.sub.20 heteroarylene, wherein the substituent of substituted C.sub.1 to C.sub.16 alkyl, the substituent of the substituted C.sub.6 to C.sub.18 arylene, C.sub.2 to C.sub.20 heteroarylene are independently selected from C.sub.6 to C.sub.18 arylene or C.sub.2 to C.sub.12 heteroarylene; n is selected from 1 to 5, wherein n is an integer number.

Claims

1. Organic electronic device comprising an organic semiconductor layer, wherein at least one organic semiconductor layer comprises a compound of formula 1:
L.sup.1-Ar.sup.1L.sup.2].sub.n   (1), wherein L.sup.1 has the formula 2: ##STR00153##  and L.sup.2 has the formula 3: ##STR00154##  wherein L.sup.1 and L.sup.2 are bonded at “*” via a single bond independently to the same or different arylene groups or heteroarylene groups of Ar.sup.1; and wherein X.sup.1, X.sup.2 are independently selected from O, S and Se; Ar.sup.1 is selected from substituted or unsubstituted C.sub.20 to C.sub.52 arylene or C.sub.14 to C.sub.64 heteroarylene, wherein the substituent of the substituted C.sub.20 to C.sub.52 arylene or C.sub.14 to C.sub.64 heteroarylene are independently selected from C.sub.1 to C.sub.12 alkyl, C.sub.1 to C.sub.12 alkoxy, CN, halogen, OH, C.sub.6 to C.sub.25 aryl and C.sub.2 to C.sub.21 heteroaryl; R.sup.1, R.sup.2 are independently selected from substituted or unsubstituted C.sub.1 to C.sub.16 alkyl, wherein the substituent of substituted C.sub.1 to C.sub.16 alkyl is selected from C.sub.6 to C.sub.18 arylene or C.sub.2 to C.sub.12 heteroarylene; R.sup.3, R.sup.4 are independently selected from substituted or unsubstituted C.sub.1 to C.sub.16 alkyl, substituted or unsubstituted C.sub.6 to C.sub.18 arylene, C.sub.2 to C.sub.20 heteroarylene, wherein the substituent of substituted C.sub.1 to C.sub.16 alkyl, the substituent of the substituted C.sub.6 to C.sub.18 arylene, C.sub.2 to C.sub.20 heteroarylene are independently selected from C.sub.6 to C.sub.18 arylene or C.sub.2 to C.sub.12 heteroarylene; n is selected from 1 to 5, wherein n is an integer number.

2. The organic electronic device according to claim 1, wherein the compound of formula 1 is represented by formula 4: ##STR00155## wherein X.sup.1, X.sup.2 are independently selected from O, S and Se; Ar.sup.1 is selected from substituted or unsubstituted C.sub.20 to C.sub.52 arylene or C.sub.14 to C.sub.64 heteroarylene, wherein the substituent of the substituted C.sub.20 to C.sub.52 arylene or C.sub.14 to C.sub.64 heteroarylene are independently selected from C.sub.1 to C.sub.12 alkyl, C.sub.1 to C.sub.12 alkoxy, CN, halogen, OH, C.sub.6 to C.sub.25 aryl and C.sub.2 to C.sub.21 heteroaryl; R.sup.1, R.sup.2 are independently selected from substituted or unsubstituted C.sub.1 to C.sub.16 alkyl, wherein the substituent of substituted C.sub.1 to C.sub.16 alkyl is selected from C.sub.6 to C.sub.18 arylene or C.sub.2 to C.sub.12 heteroarylene; R.sup.3, R.sup.4 are independently selected from substituted or unsubstituted C.sub.6 to C.sub.18 arylene, C.sub.2 to C.sub.20 heteroarylene and C.sub.1 to C.sub.16 alkyl, wherein the substituent of the substituted C.sub.6 to C.sub.18 arylene, C.sub.2 to C.sub.20 heteroarylene and C.sub.1 to C.sub.16 alkyl is selected from C.sub.6 to C.sub.18 arylene or C.sub.2 to C.sub.12 heteroarylene; n is selected from 1 to 5, wherein n is an integer number; wherein the compound of formula 4 comprises at least about 4 of C.sub.6 arylene rings.

3. The organic electronic device according to claim 1, wherein the compound of formula 1 comprises about 4 of C.sub.6 arylene groups to about 12 of C.sub.6 arylene groups.

4. The organic electronic device according to claim 1, wherein the compound of formula 1 has a dipole moment of about ≥0 and about ≤3 Debye.

5. The organic electronic device according to claim 1, wherein Ar.sup.1 has the formula 5: ##STR00156## wherein L.sup.3 and L.sup.4 are bonded at “*” via a single bond to L.sup.1 and L.sup.2, Ar.sup.2 is selected from C.sub.10 to C.sub.42 arylene or C.sub.2 to C.sub.54 heteroarylene, L.sup.3, L.sup.4 are independently selected from phenylene, biphenylene, fluoren-di-yl or a direct bond, m is selected from 1 to 5, wherein m is an integer number.

6. The organic electronic device according to claim 1, wherein Ar.sup.1 has the formula 6: ##STR00157## wherein Ar.sup.3 is bonded at “*” via a single bond to L.sup.1 and L.sup.2, Ar.sup.3 is selected from C.sub.6 to C.sub.25 arylene or 9-phenylcarbazol-di-yl, Ar.sup.4 is selected from substituted or unsubstituted C.sub.10 to C.sub.24 arylene or C.sub.2 to C.sub.28 heteroarylene, wherein the substituents on C.sub.10 to C.sub.24 arylene or C.sub.2 to C.sub.28 heteroarylene are independently selected from C.sub.1 to C.sub.12 alkyl, C.sub.1 to C.sub.12 alkoxy, CN, halogen, OH, C.sub.6 to C.sub.25 aryl and C.sub.2 to C.sub.21 heteroaryl.

7. The organic electronic device according to claim 1, wherein n is selected from about 1 to about 3, wherein n is an integer number.

8. The organic electronic device according to claim 1, wherein R.sup.1, R.sup.2 are selected from C.sub.1 to C.sub.16 alkyl, and R.sup.3, R.sup.4 are selected from C.sub.6 to C.sub.18 aryl.

9. The organic electronic device according to claim 1, wherein X.sup.1 and X.sup.2 are selected the same, or X.sup.1 and X.sup.2 are O.

10. The organic electronic device according to claim 1, wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently selected from C.sub.1 to C.sub.16 alkyl, or R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are selected the same.

11. The organic electronic device according to claim 1, wherein X.sup.1, X.sup.2 are O; Ar.sup.1 is selected from unsubstituted C.sub.20 to C.sub.52 arylene or unsubstituted C.sub.14 to C.sub.64 heteroarylene; R.sup.1, R.sup.2, R.sup.3, R.sup.4 are independently selected from unsubstituted C.sub.1 to C.sub.6 alkyl; n is selected from 1 to 3, wherein n is an integer number.

12. The organic electronic device according to claim 1, wherein the compound of formula 1 is free of heteroarylene groups or comprises at least about 1 to about 3 heteroarylene groups.

13. The organic electronic device according to claim 1, wherein Ar.sup.1, R.sup.1, R.sup.2, R.sup.3, R.sup.4, or a combination thereof comprises at least one heteroarylene group selected from the group consisting of triazine, quinazoline, quinoline, benzimidazole, benzothiazole, benzo[4,5]thieno[3,2-d]pyrimidine, pyrimidine, and pyridine.

14. The organic electronic device according to claim 1, wherein L.sup.1 and L.sup.2 are bonded at “*” via a single bond to the same arylene group or different arylene groups of Ar.sup.1.

15. The organic electronic device according to claim 1, wherein the compound of formula 1 is selected from the group of K1 to K42: ##STR00158## ##STR00159## ##STR00160## ##STR00161## ##STR00162## ##STR00163## ##STR00164## ##STR00165## ##STR00166## ##STR00167## ##STR00168## ##STR00169## ##STR00170##

16. The organic electronic device according to claim 1, wherein the organic semiconductor layer is arranged between a photoactive layer and a cathode layer, or the organic semiconductor layer is an electron transport layer.

17. The organic electronic device according to claim 1, wherein the at least one organic semiconductor layer further comprises at least one alkali halide or alkali organic complex.

18. The organic electronic device according to claim 1, (i) wherein the organic electronic device further comprises at least one anode layer, at least one cathode layer and at least one emission layer, or (ii) wherein the organic electronic device further comprises at least one emission layer and at least one cathode layer, wherein the at least one organic semiconductor layer is arranged between the at least one emission layer and the at least one cathode layer.

19. The organic electronic device according to claim 1, further comprising an electron injection layer and a cathode layer, wherein the electron injection layer is arranged between the at least one organic semiconductor layer and the cathode layer, wherein the electron injection layer comprises at least one metal and/or a metal halide or metal organic complex.

20. A process of preparing an organic electronic device according to claim 1, wherein an electron injection layer is formed by (i) a step of transferring into the gas phase a metal composition comprising a first metal selected from an alkali metal and a second metal selected from Mg, Zn, Hg, Cd and Te and a step of deposing the alkali metal on the at least one organic semiconductor layer according; or (ii) a step of transferring into the gas phase a rare earth metal and an alkali metal halide and a step of deposing the rare earth metal and alkali halide on the at least one organic semiconductor layer.

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

22. A compound having the formula 1:
L.sup.1-Ar.sup.1L.sup.2].sub.n   (1), wherein L.sup.1 has the formula 2: ##STR00171##  and L.sup.2 has the formula 3: ##STR00172##  wherein L.sup.1 and L.sup.2 are bonded at “*” via a single bond independently to the same or different arylene groups or heteroarylenes group of Ar.sup.1; and wherein X.sup.1, X.sup.2 are independently selected from O, S and Se; Ar.sup.1 is selected from substituted or unsubstituted C.sub.20 to C.sub.52 arylene or C.sub.14 to C.sub.64 heteroarylene, wherein the substituent of the substituted C.sub.20 to C.sub.52 arylene or C.sub.14 to C.sub.64 heteroarylene are independently selected from C.sub.1 to C.sub.12 alkyl, C.sub.1 to C.sub.12 alkoxy, CN, halogen, OH, C.sub.6 to C.sub.25 aryl and C.sub.2 to C.sub.21 heteroaryl; R.sub.1, R.sup.2 are independently selected from substituted or unsubstituted C.sub.1 to C.sub.16 alkyl, wherein the substituent of substituted C.sub.1 to C.sub.16 alkyl is selected from C.sub.6 to C.sub.18 arylene or C.sub.2 to C.sub.12 heteroarylene; R.sup.3, R.sup.4 are independently selected from substituted or unsubstituted C.sub.1 to C.sub.16 alkyl, substituted or unsubstituted C.sub.6 to C.sub.18 arylene, C.sub.2 to C.sub.20 heteroarylene, wherein the substituent of substituted C.sub.1 to C.sub.16 alkyl, the substituent of the substituted C.sub.6 to C.sub.18 arylene, C.sub.2 to C.sub.20 heteroarylene are independently selected from C.sub.6 to C.sub.18 arylene or C.sub.2 to C.sub.12 heteroarylene; n is selected from 1 to 5, wherein n is an integer number; wherein when Ar.sup.1 is the substituted or unsubstituted C.sub.14 to C.sub.64 heteroarylene, (i) the substituted or unsubstituted C.sub.14 to C.sub.64 heteroarylene includes at least one heteroatom selected from the group consisting of N, O, B, Si, P, and Se, or (ii) n is selected from 2 to 5.

23. An organic semiconductor layer comprising a compound of formula 1:
L.sup.1-Ar.sup.1L.sup.2].sub.n   (1), wherein L.sup.1 has the formula 2: ##STR00173##  and L.sup.2 has the formula 3: ##STR00174##  wherein L.sup.1 and L.sup.2 are bonded at “*” via a single bond independently to the same or different arylene groups or heteroarylene groups of Ar.sup.1; and wherein X.sup.1, X.sup.2 are independently selected from O, S and Se; Ar.sup.1 is selected from substituted or unsubstituted C.sub.20 to C.sub.52 arylene or C.sub.14 to C.sub.64 heteroarylene, wherein the substituent of the substituted C.sub.20 to C.sub.52 arylene or C.sub.14 to C.sub.64 heteroarylene are independently selected from C.sub.1 to C.sub.12 alkyl, C.sub.1 to C.sub.12 alkoxy, CN, halogen, OH, C.sub.6 to C.sub.25 aryl and C.sub.2 to C.sub.21 heteroaryl; R.sup.1, R.sup.2 are independently selected from substituted or unsubstituted C.sub.1 to C.sub.16 alkyl, wherein the substituent of substituted C.sub.1 to C.sub.16 alkyl is selected from C.sub.6 to C.sub.18 arylene or C.sub.2 to C.sub.12 heteroarylene; R.sup.3, R.sup.4 are independently selected from substituted or unsubstituted C.sub.1 to C.sub.16 alkyl, substituted or unsubstituted C.sub.6 to C.sub.18 arylene, C.sub.2 to C.sub.20 heteroarylene, wherein the substituent of substituted C.sub.1 to C.sub.16 alkyl, the substituent of the substituted C.sub.6 to C.sub.18 arylene, C.sub.2 to C.sub.20 heteroarylene are independently selected from C.sub.6 to C.sub.18 arylene or C.sub.2 to C.sub.12 heteroarylene; n is selected from 1 to 5, wherein n is an integer number.

24. An organic semiconductor layer comprising a compound of formula 4: ##STR00175## wherein X.sup.1, X.sup.2 are independently selected from O, S and Se; Ar.sup.1 is selected from substituted or unsubstituted C.sub.20 to C.sub.52 arylene or C.sub.14 to C.sub.64 heteroarylene, wherein the substituent of the substituted C.sub.20 to C.sub.52 arylene or C.sub.14 to C.sub.64 heteroarylene are independently selected from C.sub.1 to C.sub.12 alkyl, C.sub.1 to C.sub.12 alkoxy, CN, halogen, OH, C.sub.6 to C.sub.25 aryl and C.sub.2 to C.sub.21 heteroaryl; R.sup.1, R.sup.2 are independently selected from substituted or unsubstituted C.sub.1 to C.sub.16 alkyl, wherein the substituent of substituted C.sub.1 to C.sub.16 alkyl is selected from C.sub.6 to C.sub.18 arylene or C.sub.2 to C.sub.12 heteroarylene; R.sup.3, R.sup.4 are independently selected from substituted or unsubstituted C.sub.6 to C.sub.18 arylene, C.sub.2 to C.sub.20 heteroarylene and C.sub.1 to C.sub.16 alkyl, wherein the substituent of the substituted C.sub.6 to C.sub.18 arylene, C.sub.2 to Cao heteroarylene and C.sub.1 to C.sub.16 alkyl is selected from C.sub.6 to Cis arylene or C.sub.2 to C.sub.12 heteroarylene; n is selected from 1 to 5, wherein n is an integer number; wherein the compound of formula 4 comprises at least about 4 of C.sub.6 arylene rings.

25. The organic electronic device according to claim 1, wherein Ar.sup.1, R.sup.1, R.sup.2, R.sup.3, R.sup.4, or a combination thereof comprises at least one heteroarylene group selected from triazine or pyrimidine.

Description

DESCRIPTION OF THE DRAWINGS

(1) 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:

(2) FIG. 1 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention with an emission layer, one electron transport layer and an electron injection layer;

(3) FIG. 2 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention with an emission layer and two electron transport layers;

(4) FIG. 3 is a schematic sectional view of an OLED, according to an exemplary embodiment of the present invention with an emission layer and three electron transport layers;

(5) FIG. 4 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention with an emission layer and one electron transport layer;

(6) FIG. 5 is a schematic sectional view of an organic light-emitting diode (OLED), according to an exemplary embodiment of the present invention with an emission layer and two electron transport layers;

(7) FIG. 6 is a schematic sectional view of an OLED, according to an exemplary embodiment of the present invention with an emission layer and three electron transport layers.

(8) Reference will now be made in detail to the exemplary aspects, 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, by referring to the figures.

(9) 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.

(10) The term “contacting sandwiched” refers to an arrangement of three layers whereby the layer in the middle is in direct contact with the two adjacent layers.

(11) The organic light emitting diodes according to an embodiment of the present invention may include a hole transport region; an emission layer; and a first electron transport layer comprising a compound according to formula 1 or 4.

(12) FIG. 1 is a schematic sectional view of an organic light-emitting diode 100, according to an exemplary embodiment of the present invention. The OLED 100 comprises an emission layer 150, an electron transport layer (ETL) 161 and an electron injection layer 180, whereby the first electron transport layer 161 is disposed directly on the emission layer 150 and the electron injection layer 180 is disposed directly on the first electron transport layer 161.

(13) FIG. 2 is a schematic sectional view of an organic light-emitting diode 100, according to an exemplary embodiment of the present invention. The OLED 100 comprises an emission layer 150 and an electron transport layer stack (ETL) 160 comprising a first electron transport layer 161 and a second electron transport layer 162, whereby the second electron transport layer 162 is disposed directly on the first electron transport layer 161.

(14) FIG. 3 is a schematic sectional view of an organic light-emitting diode 100, according to an exemplary embodiment of the present invention. The OLED 100 comprises an emission layer 150 and an electron transport layer stack (ETL) 160 comprising a first electron transport layer 161, a second electron transport layer 162, and a third electron transport layer 163, whereby the second electron transport layer 162 is disposed directly on the first electron transport layer 161 and the third electron transport layer 163 is disposed directly on the first electron transport layer 162.

(15) FIG. 4 is a schematic sectional view of an organic light-emitting diode 100, according to an exemplary embodiment of the present invention. The OLED 100 comprises a substrate 110, a first anode electrode 120, a hole injection layer (HIL) 130, a hole transport layer (HTL) 140, an emission layer (EML) 150, one first electron transport layer (ETL) 161, an electron injection layer (EIL) 180, and a cathode electrode 190. The first electron transport layer (ETL) 161 comprises a compound of formula 1 or 4 and optionally an alkali halide or alkali organic complex. The electron transport layer (ETL) 161 is formed directly on the EML 150.

(16) FIG. 5 is a schematic sectional view of an organic light-emitting diode 100, according to an exemplary embodiment of the present invention. The OLED 100 comprises a substrate 110, a first anode electrode 120, a hole injection layer (HIL) 130, a hole transport layer (HTL) 140, an emission layer (EML) 150, an electron transport layer stack (ETL) 160, an electron injection layer (EIL) 180, and a cathode electrode 190. The electron transport layer (ETL) 160 comprises a first electron transport layer 161 and a second electron transport layer 162, wherein the first electron transport layer is arranged near to the anode (120) and the second electron transport layer is arranged near to the cathode (190). The first and/or the second electron transport layer comprise a compound of formula 1 or 4 and optionally an alkali halide or alkali organic complex.

(17) FIG. 6 is a schematic sectional view of an organic light-emitting diode 100, according to an exemplary embodiment of the present invention. The OLED 100 comprises a substrate 110, a first anode electrode 120, a hole injection layer (HIL) 130, a hole transport layer (HTL) 140, an emission layer (EML) 150, an electron transport layer stack (ETL) 160, an electron injection layer (EIL) 180, and a second cathode electrode 190. The electron transport layer stack (ETL) 160 comprises a first electron transport layer 161, a second electron transport layer 162 and a third electron transport layer 163. The first electron transport layer 161 is formed directly on the emission layer (EML) 150. The first, second and/or third electron transport layer comprise a compound of formula 1 or 4 and optionally an alkali halide or alkali organic complex.

(18) A substrate may be further disposed under the anode 120 or on the cathode 190. The substrate may be a substrate that is used in a general organic light emitting diode and may be a glass substrate or a transparent plastic substrate with strong mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water resistance.

(19) The hole injection layer 130 may improve interface properties between ITO as an anode and an organic material used for the hole transport layer 140, and may be applied on a non-planarized ITO and thus may planarize the surface of the ITO. For example, the hole injection layer 130 may include a material having particularly desirable conductivity between a work function of ITO and HOMO of the hole transport layer 140, in order to adjust a difference a work function of ITO as an anode and HOMO of the hole transport layer 140.

(20) When the hole transport region comprises a hole injection layer 130, the hole injection layer may be formed on the anode 120 by any of a variety of methods, for example, vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) method, or the like.

(21) When hole injection layer is formed using vacuum deposition, vacuum deposition conditions may vary depending on the material that is used to form the hole injection layer, and the desired structure and thermal properties of the hole injection layer to be formed and for example, vacuum deposition may be performed at a temperature of about 100° C. to about 500° C., a pressure of about 10.sup.−8 torr to about 10.sup.−3 torr, and a deposition rate of about 0.01 to about 100 Å/sec, but the deposition conditions are not limited thereto.

(22) When the hole injection layer is formed using spin coating, the coating conditions may vary depending on the material that is used to form the hole injection layer, and the desired structure and thermal properties of the hole injection layer to be formed. For example, the coating rate may be in the range of about 2000 rpm to about 5000 rpm, and a temperature at which heat treatment is performed to remove a solvent after coating may be in a range of about 80° C. to about 200° C., but the coating conditions are not limited thereto.

(23) Conditions for forming the hole transport layer and the electron blocking layer may be defined based on the above-described formation conditions for the hole injection layer.

(24) A thickness of the hole transport region may be from about 100 Å to about 10000 Å, for example, about 100 Å to about 1000 Å. When the hole transport region comprises the hole injection layer and the hole transport layer, a thickness of the hole injection layer may be from about 100 Å to about 10,000 Å, for example about 100 Å to about 1000 Å and a thickness of the hole transport layer may be from about 50 Å to about 2,000 Å, for example about 100 Å to about 1500 Å. When the thicknesses of the hole transport region, the HIL, and the HTL are within these ranges, satisfactory hole transport characteristics may be obtained without a substantial increase in operating voltage.

(25) A thickness of the emission layer may be about 100 Å to about 1000 Å, for example about 200 Å to about 600 Å. When the thickness of the emission layer is within these ranges, the emission layer may have improved emission characteristics without a substantial increase in operating voltage.

(26) Next, an electron transport region is disposed on the emission layer.

(27) The electron transport region may include at least one of a second electron transport layer, a first electron transport layer, and an electron injection layer.

(28) The thickness of the electron transport layer may be from about 20 Å to about 1000 Å, for example about 30 Å to about 300 Å. When the thickness of the electron transport layer is within these ranges, the electron transport layer may have improved electron transport auxiliary ability without a substantial increase in operating voltage.

(29) A thickness of the electron transport layer may be about 100 Å to about 1000 Å, for example about 150 Å to about 500 Å. When the thickness of the electron transport layer is within these ranges, the electron transport layer may have satisfactory electron transporting ability without a substantial increase in operating voltage.

(30) In addition, the electron transport region may include an electron injection layer (EIL) that may facilitate injection of electrons from the anode.

(31) The electron injection layer is disposed on an electron transport layer and may play a role of facilitating an electron injection from a cathode and ultimately improving power efficiency and be formed by using any material used in a related art without a particular limit, for example, LiF, Liq, NaCl, CsF, Li.sub.2O, BaO, Yb and the like.

(32) The electron injection layer may include at least one selected from LiF, NaCl, CsF, Li.sub.2O, and BaO.

(33) A thickness of the EIL may be from about 1 Å to about 100 Å, or about 3 Å to about 90 Å. When the thickness of the electron injection layer is within these ranges, the electron injection layer may have satisfactory electron injection ability without a substantial increase in operating voltage.

(34) The anode can be disposed on the organic layer. A material for the anode may be a metal, an alloy, or an electrically conductive compound that have a low work function, or a combination thereof. Specific examples of the material for the anode 150 may be lithium (Li, magnesium (Mg), aluminum (Al), aluminum-lithium (Al-LI, calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), etc. In order to manufacture a top-emission light-emitting device, the anode 150 may be formed as a light-transmissive electrode from, for example, indium tin oxide ITO) or indium zinc oxide IZO).

(35) According to another aspect of the invention, a method of manufacturing an organic electroluminescent device is provided, wherein on an anode electrode (120) the other layers of hole injection layer (130), hole transport layer (140), optional an electron blocking layer, an emission layer (130), first electron transport layer (161), second electron transport layer (162), electron injection layer (180), and a cathode (190), are deposited in that order; or the layers are deposited the other way around, starting with the cathode (190).

(36) Hereinafter, the embodiments are illustrated in more detail with reference to examples.

(37) However, the present disclosure is not limited to the following examples.

(38) Preparation of Compounds of Formula 1

(39) Compound of formula 1 may be prepared as described below.

Synthesis of Dialkylphosphine Oxide

(40) ##STR00042##

(41) Dialkyphosphine oxides were prepared using a known procedure (Hays, R. H., The Journal of Organic Chemistry 1968 33 (10), 3690-3694)

(42) Diethyl phosphonate (0.95 eq) is added to an ice cooled Grignard solution in THF (3 eq.) at such a rate that a temperature of the reaction mixture is maintained at 20-30° C. After stirring at room temperature for 1 h the mixture is hydrolyzed by mixing it with an ice-cold saturated aqueous solution of potassium carbonate (3 eq.). Precipitated magnesium carbonate is removed by filtration and washed several time with ethanol. Combined filtrates are concentrated in vacuum to give a crude material, which could be further purified by distillation or re-crystallization from an appropriate solvent.

(43) TABLE-US-00001 TABLE 1 Following compounds could be prepared using this procedure Starting compound Product Yield/MS data Methylmagnesium chloride Dimethylphosphine oxide 70.8%/78[M].sup.+

(44) Standard Procedure for Coupling of Dialkylphosphine Oxide with Arylhalides

(45) ##STR00043##

(46) Schleck flask is charged with arylhalide (1 eq), dialkylphoshine oxide (1 eq. per halide atom) and sealed with a rubber septum. Atmosphere is replaced by Argon and the starting compounds are dissolved in anhydrous dioxane or suspended in dioxane-THF mixture (1:1 vol.) In a separate vial, a mixture of tris(dibenzylideneacetone)dipalladium (0.5 mol %), Xantphos (1 mol %) and triethylamine (1.17 eq per halide atom) is dissolved in anhydrous dioxane (75 ml/mmol) at 24° C. for 10 min. This catalyst solution is added to the mixture of phosphine oxide and aryl halide and the reaction mixture was stirred for 8-24 h at 60° C.

(47) Work Up Procedure 1: A precipitated solid (trimethylamine salt) is separated by filtration through sintered glass filter (Pore size 4), washed two times with dioxane, combined filtrates are evaporated to a dryness under reduced pressure using a rotary evaporator. The residue is dissolved in water, pH is set to alkaline (˜14) using aqueous potassium hydroxide solution. Resulting yellow turbid aqueous layer is sequentially extracted with hexane and diethyl ether. Combined organic layers are extracted with ˜0.5M aqueous KOH solution, aqueous phases are combined, acidified by hydrochloric acid and extracted with dichloromethane. Combined extracts are washed with saturated sodium hydrocarbonate solution, brine and dried over magnesium sulfate. Solvent is removed under reduced pressure, residue is triturated with hexane, white crystalline precipitate is collected by vacuum filtration, washed with hexane and dried.

(48) Work Up Procedure 2: Reaction mixture is diluted with water, precipitated material is collected by suction using a sintered glass filter (pore 4), washed with water, methanol and dried. Crude product could be further purified by re-crystallization or trituration with appropriate solvents. Final purification is achieved by sublimation in a high vacuum.

(49) TABLE-US-00002 TABLE 2 Following compounds could be prepared using this procedure Starting compound(s) Product/(work-up procedure) Yield/MS data 1-bromo-4-iodobenzene, (4-bromophenyl)dimethylphosphine 75%/232 [M].sup.+ dimethylphosphine oxide oxide/ (1) 1-bromo-3-iodobenzene, (3-bromophenyl)dimethylphosphine 70.8%/232 [M].sup.+   dimethylphosphine oxide oxide/ (1) 0

(50) Standard Procedure for the Synthesis of Boronic Ester

(51) ##STR00052##

(52) Schleck flask is charged with arylhalide (1 eq), 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane) (1.3 eq. per halide atom), potassium acetate (3 eq) and [1,1′-Bis(diphenylphosphino)ferrocene]dichloropalladium(II) (Pd(dffp)Cl.sub.2, 0.03 eq) and sealed with a rubber septum. Atmosphere is replaced by Argon and anhydrous dioxane is added via double tipped cannula. The mixture is stirred at 60° C. for 6-48 h, the progress of the reaction is monitored by TLC.

(53) Work-Up Procedure 1: All volatiles are removed under reduced pressure, residue is triturated with toluene, insoluble anorganic salts are removed by filtration, filtrate is evaporated to dryness and triturated with methyl-tert.-butyl ether. Pale-brown crystalline precipitate is collected by vacuum filtration, washed with hexane and dried.

(54) Work-Up Procedure 2: Precipitate is collected by suction filtration, washed with water, methanol and dried in vacuum at 40° C. yielding the crude product, which is then purified by column chromatography or re-crystallization or trituration with an appropriate solvent.

(55) TABLE-US-00003 TABLE 3 Following compounds could be prepared using this procedure Starting compound(s) Product/(work-up procedure) Yield/MS data 57%/280 [M].sup.+ 69%/280 [M].sup.+ 0

(56) Standard Procedures for Suzuki-Miyaura Coupling

(57) ##STR00067##

(58) A three neck round bottom flask, equipped with dropping funnel, reflux condenser and magnetic stir bar is charged with an arylhalide (1 eq) and corresponding boronic ester or acid (1.25 eq. per halogen atom in arylhalide), the flask is sealed with a rubber septum, evacuated and back-filled with argon (2 times). Anhydrous dioxane (4 ml/mmol of arylhalide) is added through the septum using a double-tipped needle. Separately, a solution of potassium carbonate (2M in water) is prepared and degassed with N2 for 30 min. The solution is added to the reaction mixture through the septum using a double-tipped needle, followed by the addition of the tetrakis(triphenylphosphin)palladium(0) (3 mol %) under a positive nitrogen pressure. Nitrogen purged reflux condenser is attached to the flask and the reaction mixture is stirred at 90° C. for 12 h. The mixture is allowed to cool down to the room temperature, a precipitate is collected by filtration, washed with water, methanol, dried in vacuum at 40° C. to give a crude product, which is further purified by re-crystallization or trituration with appropriate solvents. Final purification is achieved by sublimation in a high vacuum.

(59) TABLE-US-00004 TABLE 4 Following compounds could be prepared using this procedure Starting compound Product Yield/MS data 60.2%/482[M].sup.+ 0 73.3%/ 482[M].sup.+ 39.6%/ 634[M].sup.+ 57.7%/ 634[M].sup.+ 0 0 00 01 02 03 04 05 06 07 08 09 0

Synthesis of ((6-(3′-(diphenylphosphoryl)-[1,1′-biphenyl]-3-yl)-1,3,5-triazine-2,4-diyl)bis([1,1′-biphenyl]-3′,3-diyl))bis(dimethylphosphine oxide)

(60) ##STR00116## ##STR00117##

Step1: 2-(3-bromophenyl)-4,6-dichloro-1,3,5-triazine

(61) ##STR00118##

(62) A 3-necked, 250 mL round bottom flask equipped with a magnetic stirrer, septum, nitrogen inlet, and addition funnel, is charged with magnesium turnings (1.2 g, 0.049 mol). The flask is sealed and the atmosphere is replaced by nitrogen. Anhydrous diethyl ether (50 mL) is added, followed by an addition of 1,2 dibromoethane (0.187 g, 1 mmol). The mixture is stirred at RT until the evolution of ethylene is stopped. The addition funnel is charged with 1,4-dibromobenzene (11.4 g, 0.048 mol),dissolved in 50 mL of anhydrous. The solution is added to the reaction mixture at the rate to maintain a gentle reflux. Ones the addition is complete, the mixture is allowed to reflux for additional 30 minutes,

(63) A 3-necked, 250 mL round bottom flask equipped with a magnetic stirrer, thermocouple, nitrogen inlet, and a septum is charged with cyanuric chloride (0.048 mol, 8.85 g). The atmosphere is replaced by nitrogen, an anhydrous THF (50 ml) is added, and the solution is cooled to −20° C. Grignard solution is added through the septum using double tipped needle with a rate to maintain the reaction temperature below −15° C. The reaction is stirred for 1 hour and warmed to 0° C. whereupon it is quenched with cold saturated ammonium chloride and partitioned between ethyl acetate and dilute sodium chloride solution. The organic layer is separated, dried over magnesium sulfate, filtered and evaporated to yield crude product that could be used directly, without further purification, in subsequent reactions.

Step2: 2-(3-bromophenyl)-4,6-bis(3-chlorophenyl)-1,3,5-triazine

(64) ##STR00119##

(65) The title compound is prepared from 2-(3-bromophenyl)-4,6-dichloro-1,3,5-triazine (10 g, 0.033 mol) and (3-chlorophenyl)boronic acid (2.2 eq, 11.35 g) using standard protocol for Suzuki-Miyaura coupling, described above. A crude product is purified by recrystallization from DFM.

Step3: (3′-(4,6-bis(3-chlorophenyl)-1,3,5-triazin-2-yl)-[1,1′-biphenyl]-3-yl)diphenylphosphine oxide

(66) ##STR00120##

(67) The title compound is prepared from 2-(3-bromophenyl)-4,6-bis(3-chlorophenyl)-1,3,5-triazine (10 g, 0.022 mol) and diphenyl(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)phosphine oxide (1 eq, 8.84 g) using standard protocol for Suzuki-Miyaura coupling, described above.

Step4: ((6-(3′-(diphenylphosphoryl)-[1,1′-biphenyl]-3-yl)-1,3,5-triazine-2,4-diyl)bis([1,1′-biphenyl]-3′,3-diyl))bis(dimethylphosphine oxide)

(68) ##STR00121##

(69) The title compound is prepared from (3′-(4,6-bis(3-chlorophenyl)-1,3,5-triazin-2-yl)-[1,1′-biphenyl]-3-yl)diphenylphosphine oxide (10 g, 0.015 mol) and dimethyl(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)phosphine oxide (2.2 eq, 9.24 g) using standard protocol for Suzuki-Miyaura coupling, described above.

Synthesis of (9-(3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-9H-carbazole-2,7-diyl)bis(dimethylphosphine oxide)

(70) ##STR00122##

Step1: (9H-carbazole-2,7-diyl)bis(dimethylphosphine oxide)

(71) ##STR00123##

(72) The title compound is prepared from 2,7-dibromo-9H-carbazole (32.5 g, 0.1 mol) and dimethylphosphine oxide (2.2 eq, 17.17 g) using standard protocol for dialkylphosphine coupling reaction.

Step2: (9-(3-bromophenyl)-9H-carbazole-2,7-diyl)bis(dimethylphosphine oxide)

(73) ##STR00124##

(74) A 3-neck, 250 mL round bottom flask equipped with a magnetic stirrer, nitrogen inlet, and reflux condenser, is charged with (9H-carbazole-2,7-diyl)bis(dimethylphosphine oxide) (20 g, 0.063 mol), 1-bromo-3-iodobenzene (1.5 eq. 26.58 g), copper(I)iodide (20 mol %, 12.6 mmol, 2.4 g), 1,10-phenanthroline (20 mol %, 12.6 mmol, 2.27 g) and DMF (170 ml). The flask is sealed, the atmosphere is replaced by nitrogen, reaction mixture is stirred at reflux condition for 24 h.

(75) After cooling down to RT, the reaction mixture is partitioned between water (500 ml) and methylene chloride (200 ml). Organic phase is separated, washed with water, brine, dried over magnesium sulfate, filtered through a short pad of SiO2, and evaporated to dryness. Oily residue solidify upon trituration with hexane, the solid is collected by suction filtration, washed with hexane and dried in vacuum to yield the title product.

Step3: (9-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-9H-carbazole-2,7-diyl)bis(dimethylphosphine oxide)

(76) ##STR00125##

(77) (9-(3-bromophenyl)-9H-carbazole-2,7-diyl)bis(dimethylphosphine oxide) (15 g, 31.6 mmol) is converted to the corresponding boronic ester using the standard protocol, described above.

Step4: (9-(3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-9H-carbazole-2,7-diyl) bis(dimethylphosphine oxide)

(78) ##STR00126##

(79) The title compound is prepared from 2-chloro-4,6-diphenyl-1,3,5-triazine (5 g, 18.7 mmol) and (9-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-9H-carbazole-2,7-diyl)bis(dimethylphosphine oxide) (1 eq, 18.7 mmol, 9.74 g) using standard protocol for Suzuki-Miyaura coupling, described above.

Synthesis of (9-phenyl-9-(3-(4-([1,1′-biphenyl]-4-yl)-6-phenyl-1,3,5-triazinyl)phenyl)-9H-fluorene-2,7-diyl)bis(dimethylphosphine oxide)

(80) ##STR00127##

Step1. 2,7-dibromo-9-(3-chlorophenyl)-9-phenyl-9H-fluorene

(81) ##STR00128##

(82) A 3-necked, 250 mL round bottom flask equipped with a magnetic stirrer, thermometer, addition funnel, sealed with a rubber septum, and nitrogen inlet, is charged with 4,4′-dibromo-2-iodo-1,1′-biphenyl (43.8 g, 0.1 mol). The flask is sealed and the atmosphere is replaced by nitrogen. The solid is dissolved in anhydrous THF (100 mL) and the solution is cooled to −78° C. Addition funnel is charged with n-butyl lithium solution (2.5M in hexane, 1 eq. 40 ml). The solution is added to the reaction mixture dropwise at −78° C., the funnel is washed with small amount of anhydrous THF. Ones the addition is complete, the mixture is allowed to react for additional 30 minutes at −78° C., then addition funnel is charged with (3-chlorophenyl)(phenyl)-methanone (1 eq, 0.1 mol, 21.7 g), dissolved in 100 ml of anhydrous THF. This solution is added to reaction mixture dropwise at −78° C., reaction is stirred for additional 30 min at −78° C., then allowed to reach the room temperature overnight.

(83) The solvent is evaporated at reduced pressure, the residue is dissolved in glacial acetic acid (150 ml). Concentrated hydrochloric acid solution (32%, 16 ml) is added, he mixture was heated to reflux for 3.5 h and stirred overnight at room temperature. Obtained suspension is diluted with water, extracted with DCM. Combined organic extracts are washed with water, dried over magnesium sulfate and evaporated to a dryness yielding a crude product. Final purification is achieved by recrystallization from isopropanol (700 ml).

Step2: (9-(3-chlorophenyl)-9-phenyl-9H-fluorene-2,7-diyl)bis(dimethylphosphine oxide)

(84) ##STR00129##

(85) The title compound is prepared from 2,7-dibromo-9-(3-chlorophenyl)-9-phenyl-9H-fluorene (30 g, 58.8 mmol) using the standard procedure, described above. Purification of the final compound is achieved by re-crystallization from chlorobenzene.

Step3: (9-phenyl-9-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-9H-fluorene-2,7-diyl)bis(dimethylphosphine oxide)

(86) ##STR00130##

(87) (9-(3-chlorophenyl)-9-phenyl-9H-fluorene-2,7-diyl)bis(dimethylphosphine oxide) (20 g, 39.6 mmol) is converted to the corresponding boronic ester using the standard protocol, described above.

Step4: (9-phenyl-9-(3-(4-([1,1′-biphenyl]-4-yl)-6-phenyl-1,3,5-triazinyl)phenyl)-9H-fluorene-2,7-diyl)bis(dimethylphosphine oxide)

(88) ##STR00131##

(89) The title compound was prepared from (9-phenyl-9-(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-9H-fluorene-2,7-diyl)bis(dimethylphosphine oxide) (16.5 g, 27.7 mmol) and 2-([1,1′-biphenyl]-4-yl)-4-chloro-6-phenyl-1,3,5-triazine (1 eq, 27.7 mmol, 9.52 g) using standard protocol for Suzuki-Miyaura coupling.

(5-(4-(4-(4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazin-2-yl)phenyl)naphthalen-1-yl)-1,3-phenylene)bis(dimethylphosphine oxide)

(90) ##STR00132## ##STR00133##

Step1: (5-chloro-1,3-phenylene)bis(dimethylphosphine oxide)

(91) ##STR00134##

(92) The title compound is obtained from 1,3-dibromo-5-chlorobenzene (54.07 g, 0.2 mol) and dimethylphosphine oxide (2 eq. 0.4 mol, 31.22 g) using the standard procedure for coupling of dialkylphosphine oxide

Step2: (5-(4,4,5,5-tetramethyl-, 3,2-dioxaborolan-2-yl)-1,3-phenylene)bis(dimethylphosphine oxide)

(93) ##STR00135##

(94) (5-chloro-1,3-phenylene)bis(dimethylphosphine oxide) (34.4 g, 0.13 mol) is converted to the title compound using standard protocol, described above.

Step3: (5-(4-bromonaphthalen-1-yl)-1,3-phenylene)bis(dimethylphosphine oxide)

(95) ##STR00136##

(96) The title compound is prepared from (5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,3 phenylene)bis(dimethylphosphine oxide) (28.7 g, 8.06 mmol) and 1-bromo-4-iodonaphthalene (1 eq. 8.06 mmol, 26.8 g) using standard protocol for Suzuki-Miyaura coupling

Step4 (5-(4-(4-chlorophenyl)naphthalen-1-yl)-1,3-phenylene)bis(dimethylphosphine oxide)

(97) ##STR00137##

(98) The title compound is prepared from (5-(4-bromonaphthalen-1-yl)-1,3-phenylene) bis(dimethylphosphine oxide) (30 g, 6.89 mmol) and (4-chlorophenyl)boronic acid (1 eq. 6.89 mmol, 10.78 g) using standard protocol for Suzuki-Miyaura coupling

Step5: (5-(4-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)naphthalen-1-yl)-1,3-phenylene)bis(dimethylphosphine oxide)

(99) ##STR00138##

(100) (5-(4-(4-chlorophenyl)naphthalen-1-yl)-1,3-phenylene)bis(dimethylphosphine oxide) (25.7 g, 5.5 mmol) is converted to corresponding boronic ester using the standard procedure, described above.

Step 6: (5-(4-(4-(4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazin-2-yl)phenyl)naphthalen-1-yl)-1,3-phenylene)bis(dimethylphosphine oxide)

(101) ##STR00139##

(102) The title compound is prepared from (5-(4-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)naphthalen-1-yl)-1,3-phenylene)bis(dimethylphosphine oxide) (12 g, 2.15 mmol) and 2-chloro-4-(dibenzo[b,d]furan-3-yl)-6-phenyl-1,3,5-triazine (1 eq. 2.15 mmol, 7.69) using standard protocol for Suzuki-Miyaura coupling

Synthesis of (5-(4-(4-(4-(dibenzo[b,d]furan-3-yl)quinazolin-2-yl)phenyl)naphthalen-1-yl)-1,3-phenylene)bis(dimethylphosphine oxide)

(103) ##STR00140##

Step1: 2-chloro-4-(dibenzo[b,d]furan-3-yl)quinazoline

(104) ##STR00141##

(105) The title compound is prepared from 2,4-dichloroquinazoline (25 g, 0.126 mol) and dibenzo[b,d]furan-3-ylboronic acid (1 eq. 0.126 mol, 26.6 g) using standard protocol for Suzuki-Miyaura coupling

Step2: (5-(4-(4-(4-(dibenzo[b, d]furan-3-yl)quinazolin-2-yl)phenyl)naphthalen-1-yl)-1,3-phenylene)bis(dimethylphosphine oxide)

(106) ##STR00142##

(107) The title compound is prepared from (5-(4-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)naphthalen-1-yl)-1,3-phenylene)bis(dimethylphosphine oxide) (12 g, 2.15 mmol) and 2-chloro-4-(dibenzo[b,d]furan-3-yl)quinazoline (1 eq. 2.15 mmol, 7.1 g) using standard protocol for Suzuki-Miyaura coupling.

Synthesis of (5′-(4-([1,1′-biphenyl]-3-yl)-6-(dibenzo[b,d]furan-3-yl)-1,3,5-triazin-2-yl)-[1,1′:3′,1″-terphenyl]-3,3″-diyl)bis(dimethylphosphine oxide)

(108) ##STR00143##

Step1: (5′-chloro-[1,1′:3′,1″-terphenyl]-3,3″-diyl)bis(dimethylphosphine oxide)

(109) ##STR00144##

(110) The title compound is prepared from 1,3-dibromo-5-chlorobenzene (54.07 g, 0.2 mol) and dimethyl(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)phosphine oxide (2 eq. 0.4 mol, 112.04 g) using standard protocol for Suzuki-Miyaura coupling

Step2: (5′-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-[1,1′:3′,1″-terphenyl]-3,3″-diyl)bis(dimethylphosphine oxide)

(111) ##STR00145##

(112) (5′-chloro-[1,1′:3′,1″-terphenyl]-3,3″-diyl)bis(dimethylphosphine oxide) (54 g, 0.13 mol) is converted to the boronic ester using the procedure, described above.

Step3: (5′-(4-([1,1′-biphenyl]-3-yl)-6-(dibenzo[b, d]furan-3-yl)-1,3,5-triazin-2-yl)-[1,1′:3′,1″-terphenyl]-3,3″-diyl)bis(dimethylphosphine oxide)

(113) ##STR00146##

(114) The title compound is prepared from (5′-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-[1,1′: 3′,1″-terphenyl]-3,3″-diyl)bis(dimethylphosphine oxide) (10 g, 19.7 mmol) and 2-([1,1′-biphenyl]-3-yl)-4-chloro-6-(dibenzo[b,d]furan-3-yl)-1,3,5-triazine (1 eq. 19.7 mol, 8.54 g) using standard protocol for Suzuki-Miyaura coupling

Synthesis of (5′-(4-(dibenzo[b,d]thiophen-2-yl)-6-(dibenzo[b,d]thiophen-3-yl)pyrimidin-2-yl)-[1,1′:3′,1″-terphenyl]-3,3″-diyl)bis(dimethylphosphine oxide)

(115) ##STR00147##

(116) The title compound is prepared from (5′-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-[1,1′:3′,1″-terphenyl]-3,3″-diyl)bis(dimethylphosphine oxide) (10 g, 19.7 mmol) and 2-chloro-4,6-bis(dibenzo[b,d]thiophen-3-yl)pyrimidine (1 eq. 19.7 mol, 9.43 g) using standard protocol for Suzuki-Miyaura coupling

(117) General Procedure for Fabrication of Organic Electronic Devices

(118) Electron-only devices and OLEDs were prepared to demonstrate the technical benefit utilizing the compounds of formula 1 in an organic electronic device.

(119) Electron-Only Devices

(120) For electron-only devices (EOD), see Table 5 and 6, a glass substrate was cut to a size of 50 mm×50 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. 100 nm Ag were deposited as anode on the glass at a pressure of 10.sup.−5 to 10.sup.−7 mbar.

(121) Then, MgAg alloy (90:10 vol.-%) was deposited on the anode electrode to form a layer with a thickness of 30 nm.

(122) Then, LiQ was deposited on the MgAg layer to form a layer with a thickness of 1 nm.

(123) Then, an organic semiconductor layer was deposited on the LiQ layer to form an organic semiconductor layer with a thickness of 36 nm.

(124) In examples 1 to 4 (Table 5), the organic semiconductor layer consisted of compound of formula 1. In comparative example 1, MX1 [anthracene-9,10-diylbis(4,1-phenylene))bis(diphenyl-phosphine oxide), CAS 1257261-60-1] was used instead, see Table 5.

(125) In examples 5 to 8 (Table 6), the organic semiconductor layer comprised 70 vol.-% compound of formula 1 and 30 vol.-% alkali organic complex. In comparative example 1, MX1 was used in place of compound of formula 1, see Table 6.

(126) Then, LiQ was deposited to form a layer with a thickness of 1 nm.

(127) Then, MgAg alloy (90:10 vol.-%) was deposited on the LiQ layer to form a cathode electrode with a thickness of 30 nm.

(128) Bottom Emission Devices with an Evaporated Emission Layer

(129) For bottom emission devices—Examples 9 to 12 and comparative example 3 in Table 7, a 15 Ω/cm.sup.2 glass substrate with 90 nm ITO (available from Corning Co.) was cut to a size of 50 mm×50 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.

(130) Then, 97 vol.-% of Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine (CAS 1242056-42-3) and 3 vol.-% of 2,2′,2″-(cyclopropane-1,2,3-triylidene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) was vacuum deposited on the ITO electrode, to form a HIL having a thickness of 10 nm. 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 120 nm. 97 vol.-% of 2-(10-phenyl-9-anthracenyl)-benzo[b]naphtho[2,3-d]furan (CAS 1627916-48-6) as a host and 3 vol.-% of NUBD370 (Sun Fine Chemicals) as a dopant were deposited on the HTL, to form a blue-emitting EML with a thickness of 20 nm.

(131) Then, the electron transport layer is formed directly on the EML. In examples 9 to 12, the electron transport layer is formed by deposing the compound of formula 1 from a first deposition source and the alkali organic complex from a second deposition source directly on the EML. In comparative example 3, MX1 is deposed on the EML. The alkali organic complex is LI-1 (Lithium tetra(1H-pyrazol-1-yl)borate). The thickness of the electron transport layer is 36 nm.

(132) Then, the cathode electrode layer is formed by evaporating aluminum at ultra-high vacuum of 10.sup.−7 bar and deposing the cathode layer directly on the organic semiconductor layer. A thermal single co-evaporation is performed with a rate of 0, 1 to 10 nm/s (0.01 to 1 Å/s) in order to generate a homogeneous cathode electrode. The thickness of the cathode electrode layer is 100 nm.

(133) Bottom Emission Devices with a Solution-Processed Emission Layer

(134) For bottom emission devices, a 15 Ω/cm.sup.2 glass substrate with 90 nm ITO (available from Corning Co.) was cut to a size of 50 mm×50 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.

(135) Then, PEDOT:PSS (Clevios P VP AI 4083) is spin-coated directly on top of the first electrode to form a 55 nm thick HIL. The HIL is baked on hotplate at 150° C. for 5 min. Then, a light-emitting polymer, for example MEH-PPV, is spin-coated directly on top of the HIL to form a 40 nm thick EML. The EML is baked on a hotplate at 80° C. for 10 min. The device is transferred to an evaporation chamber and the following layers are deposited in high vacuum.

(136) The compound of formula 1 and an alkali organic complex are deposed directly on top of the EML to form the organic semiconductor layer with a thickness of 4 nm. A cathode electrode layer is formed by deposing a 100 nm thick layer of aluminum directly on top of the organic semiconductor layer.

(137) Pn Junction Device as Model for an OLED Comprising at Least Two Emission Layers

(138) The fabrication of OLEDs comprising at least two emission layers is time-consuming and expensive. Therefore, the effectiveness of the organic semiconductor layer of the present invention in a pn junction was tested without emission layers. In this arrangement, the organic semiconductor layer functions as n-type charge generation layer (CGL) and is arranged between the anode electrode and the cathode electrode and is in direct contact with the p-type CGL.

(139) For pn junction devices, a 15 Ω/cm.sup.2 glass substrate with 90 nm ITO (available from Corning Co.) was cut to a size of 50 mm×50 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.

(140) Then, 97 vol.-% of Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine (CAS 1242056-42-3) and 3 vol.-% of 2,2′,2″-(cyclopropane-1,2,3-triylidene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) was vacuum deposited on the ITO electrode, to form a HIL having a thickness of 10 nm. Then 2,4-diphenyl-6-(3′-(triphenylen-2-yl)-[1,1′-biphenyl]-3-yl)-1,3,5-triazine (CAS 1638271-85-8) was vacuum deposited on the HIL, to form an electron blocking layer (EBL) having a thickness of 130 nm.

(141) Then, the organic semiconductor layer is formed by deposing a matrix compound and metal organic complex by deposing the matrix compound from a first deposition source and rare earth metal dopant from a second deposition source directly on the EBL.

(142) Then, the p-type CGL is formed by deposing the host and p-type dopant directly onto the organic semiconductor layer. 97 vol.-% of Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine, referred to as HT-1, and 3 vol.-% of 2,2′,2″-(cyclopropane-1,2,3-triylidene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile), referred to as Dopant 1, was vacuum deposited to form a p-type CGL having a thickness of 10 nm.

(143) Then, a layer of 30 nm Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine is deposed directly on the p-type CGL to form a hole blocking layer (HBL).

(144) Then, the cathode electrode layer is formed by evaporating aluminum at ultra-high vacuum of 10.sup.−7 bar and deposing the aluminum layer directly on the organic semiconductor layer. A thermal single co-evaporation of one or several metals is performed with a rate of 0, 1 to 10 nm/s (0.01 to 1 Å/s) in order to generate a homogeneous cathode electrode. The thickness of the cathode electrode layer is 100 nm.

(145) Top Emission Devices with an Evaporated Emission Layer

(146) For top emission devices—Examples 13 to 21 in Table 8, a glass substrate was cut to a size of 50 mm×50 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 the substrate. 100 nm Ag was deposited on the substrate to form a first electrode.

(147) 92 vol.-% of Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine (CAS 1242056-42-3) and 8 vol.-% of 2,2′,2″-(cyclopropane-1,2,3-triylidene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) was vacuum deposited on the first electrode, to form a HIL having a thickness of 10 nm. 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 121 nm (Examples 13 to 20) or 118 nm (Example 21). 97 vol.-% H09 (Sun Fine Chemicals) as a host and 3 vol.-% BD200 (Sun Fine Chemicals) as a fluorescent blue emitting dopant were deposited on the HTL, to form a blue-emitting EML with a thickness of 20 nm. 2,4-diphenyl-6-(4′,5′,6′-triphenyl-[1,1′:2′,1″:3″,1′″:3′″,1″″-quinquephenyl]-3″″-yl)-1,3,5-triazine was deposited directly on the EML to form a hole blocking layer (HBL) with a thickness of 5 nm.

(148) The electron transport layer (ETL) is formed directly on the HBL. In examples 13, 15, 17, 19 and 21, the ETL is formed by deposing compound of formula 1 directly on the EML. In examples 14, 16, 18 and 20, the electron transport layer is formed by deposing the compound of formula 1 from a first deposition source and the alkali organic complex from a second deposition source directly on the EML. The alkali organic complex is LI-1 (Lithium tetra(1H-pyrazol-1-yl)borate). The composition and thickness of the ETL can be seen in Table 8.

(149) In examples 13 and 14 the cathode electrode layer is formed directly on the ETL.

(150) In examples 15 to 21, an electron injection layer (EIL) is formed directly on the ETL, followed by the cathode electrode layer. The composition of the material loaded into the VTE sources and the thickness of the deposited layer can be seen in Table 8. Zn:Na alloy is evaporated from one VTE source, see examples 17 to 20. Yb and KI are evaporated from two VTE sources, see example 21

(151) The cathode electrode layer is formed by evaporating the cathode material at ultra-high vacuum of 10.sup.−7 bar and deposing the cathode layer directly on the ETL or EIL. A thermal single co-evaporation or sputtering process of one or several metals is performed with a rate of 0, 1 to 10 nm/s (0.01 to 1 Å/s) in order to generate a homogeneous cathode electrode. In examples 13 to 20, the cathode electrode is formed from 11 nm Ag:Mg (85:15 vol.-%). In example 21, the cathode electrode is formed from 11 nm Ag. Biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine was vacuum deposited on the cathode electrode, to form a capping layer having a thickness of 60 nm (Examples 13 to 21) or 75 nm (Example 21).

(152) The device is protected from ambient conditions by encapsulation of the device with a glass slide. Thereby, a cavity is formed, which comprises a getter material for further protection.

(153) To assess the performance of the inventive examples compared to the prior art, the current efficiency is measured under ambient conditions (20° C.). Current voltage measurements are performed using a Keithley 2400 source meter, and recorded in V. At 10 mA/cm.sup.2 for bottom emission and 10 mA/cm.sup.2 for top emission devices, a calibrated spectrometer CAS140 from Instrument Systems is used for measurement of CIE coordinates and brightness in Candela. Lifetime LT of bottom emission device is measured at ambient conditions (20° C.) and 10 mA/cm.sup.2, using a Keithley 2400 source meter, and recorded in hours. Lifetime LT of top emission device is measured at ambient conditions (20° C.) and 8 mA/cm.sup.2. 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.

(154) In pn junction devices, the operating voltage is determined at 10 mA/cm.sup.2 as described for OLEDs above.

Technical Effect of the Invention

(155) In Table 5 are shown the dipole moment, glass transition temperature Tg, rate onset temperature T.sub.RO of compound of formula 1 (examples 1 to 4) and of comparative example 1. Additionally, the operating voltage of electron-only devices at 10 mA/cm.sup.2 comprising an organic semiconductor layer consisting of compound of formula 1 is shown. Operating voltage in electron-only devices provides an indirect indication of conductivity. The lower the operating voltage the higher the conductivity.

(156) In comparative example 1, MX1 has a dipole moment of 3.52 Debye and a rate onset temperature of 308° C. The operating voltage is high at 2.4 V.

(157) In example 1, the dipole moment is 0.24 Debye, the rate onset temperature is reduced at 279° C. and the operating voltage is reduced significantly to 0.1 V.

(158) In examples 2 to 4, the dipole moment is between 0.01 and 0.1 Debye, the rate onset temperature is between 286 and 354° C. and the operating voltage is very low in all examples.

(159) In summary, compound of formula 1 may have very high conductivity and a significant reduction in operating voltage may be achieved. The glass transition temperature and rate onset temperature are within the range acceptable for mass production of organic semiconductor layers.

(160) TABLE-US-00005 TABLE 5 Dipole moment (calculated with B3LYP_Gaussian/6-31G), glass transition temperature, rate onset temperature and operating voltage in electron-only devices Operating voltage at Dipole 10 moment Tg T.sub.RO mA/cm.sup.2 Name Formula [Debye] [° C.] [° C.] [V] Comp. example 1 MX1 3.52 — 308 2.4 Example 1 MX2 0.24 — 279 0.1 Example 2 MX3 0 0.01 — 286 0.6 Example 3 MX4 0.10 201 354 0.3 Example 4 MX5 0.08 141 298 0.5

(161) In Table 6 are shown operating voltages of an organic semiconductor layer comprising a compound of formula 1 (examples 5 to 8) and alkali organic complex. The alkali organic complex is LI-1 (Lithium tetra(1H-pyrazol-1-yl)borate).

(162) In comparative example 2, the operating voltage is very high at 0.95 V. In examples 5 to 8, the operating voltage is reduced significantly to 0.3 to 0.5 V. Thereby, the beneficial effect of high conductivity of compound of formula 1 is observed also in an organic semiconductor layer comprising further an alkali organic complex.

(163) TABLE-US-00006 TABLE 6 Electron-only devices of an organic semiconductor layer comprising a compound of formula 1 and an alkali organic complex Operating vol.-% voltage vol.-% Alkali alkali at 10 Compound of compound of organic organic mA/cm.sup.2 formula 1 formula 1 complex complex (V) Comparative MX1 70 LI-1 30 0.95 example 2 Example 5 MX2 70 LI-1 30 0.3 Example 6 MX3 70 LI-1 30 0.3 Example 7 MX4 70 LI-1 30 0.5 Example 8 MX5 70 LI-1 30 0.3

(164) In Table 7, see below, data for bottom emission OLEDs are shown. In examples 9 to 12, the first electron transport layer comprises compound of formula 1 and alkali organic complex LI-1. In comparative example 3, the first electron transport layer comprises MX1 and alkali organic complex LI-1. As can be seen in Table 7, the operating voltage is reduced significantly in examples 9 to 12 compared to comparative example 3. Additionally, in example 10 to 12, the cd/A efficiency is improved.

(165) In summary, a beneficial effect of compound of formula ion operating voltage is observed when used in the first or second electron transport layer.

(166) In Table 8, data for top emission OLEDs are shown. In example 13 and 14, the electron transport layer comprises a compound of formula 1. The operating voltage is low at 3.7 and 4.05 V, respectively, and the cd/A efficiency is very high at 9.5 and 7.3 cd/A, respectively.

(167) The operating voltage is reduced further when an EIL is arranged between the electron transport layer comprising compound of formula 1 and the cathode electrode, see examples 15 to 21. Particularly low operating voltage can be achieved when a metal composition comprising Na and Zn is evaporated from one VTE source to form an EIL, see examples 17 to 21. A similar beneficial effect can be achieved, when Yb and KI are evaporated together from two VTE sources to form an EIL, see Example 21.

(168) TABLE-US-00007 TABLE 7 Bottom emission OLED performance of a first electron transport layer comprising a compound of formula 1 and an alkali organic complex vol.- % Operating Compound vol.- % Alkali alkali voltage at cd/A efficiency of compound of organic organic Thickness 10 at 10 formula 1 formula 1 complex complex ETL1 / nm mA/cm.sup.2 (V) mA/cm.sup.2 (cd/A) Comparative MX1 70 LI-1 30 36 4.25 5.9 example 3 Example 9 MX2 70 LI-1 30 36 3.6 5.85 Example 10 MX3 70 LI-1 30 36 3.6 6.1 Example 11 MX4 70 LI-1 30 36 3.9 6.3 Example 12 MX5 70 LI-1 30 36 3.6 6.25

(169) TABLE-US-00008 TABLE 8 Top emission OLED performance of an electron transport layer comprising a compound of formula 1 vol.- % Operating cd/A Compound compound voltage at efficiency of of vol.- % Thickness Thickness Thickness 10 mA/cm.sup.2 at 10 mA/cm.sup.2 formula 1 formula 1 Dopant Dopant ETL/nm EIL1 EIL1/nm EIL2 EIL2 (V) (cd/A) Example 13 MX2 100 — 0 31 — 0 — 0 3.7 9.5 Example 14 MX2 70 LI-1 30 31 — 0 — 0 4.05 7.3 Example 15 MX2 100 — 0 31 Yb 2 — 0 4 7.2 Example 16 MX2 70 LI-1 30 31 Yb 2 — 0 3.6 9.1 Example 17 MX2 100 — 0 31 Zn:Na 3 Yb 2 3.4 8.5 (97.4:2.6 wt.- %) Example 18 MX2 70 LI-1 30 31 Zn:Na 3 Yb 2 3.4 8.9 (97.4:2.6 wt.- %) Example 19 MX2 100 — 0 31 Zn:Na 3 — 0 3.4 9.0 (97.4:2.6 wt.- %) Example 20 MX2 70 LI-1 30 31 Zn:Na 3 — 0 3.4 8.7 (97.4:2.6 wt.- %) Example 21 MX2 100 — 0 31 Yb:KI 2 — 0 3.45 6.9 (50:50 vol.- %)

(170) 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.