Organic electronic device comprising an organic semiconductor layer and a device
11795186 · 2023-10-24
Assignee
Inventors
Cpc classification
H10K85/6572
ELECTRICITY
C07F9/65128
CHEMISTRY; METALLURGY
C07F9/6561
CHEMISTRY; METALLURGY
H10K85/6574
ELECTRICITY
C07F9/65583
CHEMISTRY; METALLURGY
International classification
C07F9/6512
CHEMISTRY; METALLURGY
C07F9/6558
CHEMISTRY; METALLURGY
C07F9/6561
CHEMISTRY; METALLURGY
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 X is selected from O, S or Se; Ar.sup.1 is selected from unsubstituted or substituted C.sub.2 to C.sub.60 heteroarylene, and wherein the substituted C.sub.2 to C.sub.60 heteroarylene comprises at least about one to about six substituents, wherein the substituent of the substituted C.sub.2 to C.sub.60 heteroarylene are independently selected from C.sub.1 to C.sub.12 alkyl, C.sub.1 to C.sub.12 alkoxy, CN, OH, halogen, C.sub.6 to C.sub.36 arylene, or C.sub.2 to C.sub.25 heteroarylene; n is 1 or 2; L.sup.1 is selected from a single bond, C.sub.1 to C.sub.4 alkyl, substituted or unsubstituted C.sub.6 to C.sub.36 arylene, wherein the substituent of substituted C.sub.6 to C.sub.36 arylene is selected from C.sub.1 to C.sub.12 alkyl, C.sub.6 to C.sub.18 arylene; L.sup.2 is selected from a single bond or C.sub.1 to C.sub.6 alkyl; 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; wherein the compound of formula 1 comprises at least about 4 of C.sub.6-arylene rings and a molecular mass of at least about 400 g/mol to about 1800 g/mol. ##STR00001##
Claims
1. Organic electronic device comprising at least one organic semiconductor layer, wherein the at least one organic semiconductor layer comprises a compound of formula 1: ##STR00116## wherein X is selected from O, S or Se; Ar.sup.1 is selected from unsubstituted or substituted C.sub.2 to C.sub.60 heteroarylene, and wherein the substituted C.sub.2 to C.sub.60 heteroarylene comprises at least about one to about six substituents, wherein the substituent of the substituted C.sub.2 to C.sub.60 heteroarylene are independently selected from C.sub.1 to C.sub.12 alkyl, C.sub.1 to C.sub.12 alkoxy, CN, OH, halogen, C.sub.6 to C.sub.36 arylene, or C.sub.2 to C.sub.25 heteroarylene; n is 1 or 2; L.sup.1 is selected from a single bond, C.sub.1 to C.sub.4 alkyl, substituted or unsubstituted C.sub.6 to C.sub.36 arylene, wherein the substituent of substituted C.sub.6 to C.sub.36 arylene is selected from C.sub.1 to C.sub.12 alkyl, C.sub.6 to C.sub.18 arylene; L.sup.2 is selected from a single bond or C.sub.1 to C.sub.6 alkyl, 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, wherein the compound of formula 1 comprises: at least about 4 of C.sub.6-arylene rings, a molecular mass of at least about 400 g/mol to about 1800 g/mol; wherein Ar.sup.1 comprises at least one N-heteroaryl group selected from the group comprising a triazine, quinazoline, quinoline, benzimidazole, benzothiazole, benzo[4,5]thieno[3,2-d]pyrimidine, pyrimidine and pyridine.
2. The organic electronic device according to claim 1, wherein the compound of formula 1 comprises at least about 4 to about 12 C.sub.6-arylene rings, or at least about 4 to about 12 condensed C.sub.6-arylene rings.
3. The organic electronic device according to claim 1, wherein L.sup.1 bonds via a single bond directly on a heteroarylene group of Ar.sup.1.
4. The organic electronic device according to claim 1, wherein in formula 1: X is selected from 0 or S; Ar.sup.1 is selected from unsubstituted or substituted C.sub.3 to C.sub.51 heteroarylene, and wherein the substituted C.sub.3 to C.sub.51 heteroarylene comprises at least one to three substituents, wherein the substituent of the substituted C.sub.3 to C.sub.51 heteroarylene are independently selected from C.sub.1 to C.sub.12 alkyl, CN, C.sub.6 to C.sub.36 arylene or C.sub.2 to C.sub.25 heteroarylene; n is 1 or 2; L.sup.1 is selected from unsubstituted C.sub.6 to C.sub.36 arylene, wherein L.sup.1 comprises at least one to six aromatic-6-member rings; L.sup.2 is selected from a single bond or C.sub.1 to C.sub.6 alkyl, R.sup.1, R.sup.2 are independently selected from unsubstituted C.sub.1 to C.sub.4 alkyl.
5. The organic electronic device according to claim 1, wherein Ar.sup.1 has the chemical structure B1 to B12: ##STR00117## ##STR00118## wherein Ar.sup.1 is bonded at “*” to L.sup.1 via a single bond; and wherein W, Y, Z are independently selected from N, S, O, CH or CR.sup.3, wherein at least one of W, Y, Z is selected from N, S or O, or at least W and Y are N; E.sup.1 is selected from N—Ar.sup.2, O or S; R.sup.3 and R.sup.4 are independently selected from H, C.sub.1 to C.sub.16 alkyl, or Ar.sup.2; Ar.sup.2 is independently selected from substituted or unsubstituted C.sub.6 to C.sub.36 arylene, C.sub.2 to C.sub.25 heteroarylene, wherein in structure B3 and structure B5 at least two ring atoms of the arylene or heteroarylene of Ar.sup.2 forms with E.sup.1 at least a five member ring, and wherein the substituent of the substituted C.sub.6 to C.sub.36 arylene and of the substituted C.sub.2 to C.sub.25 heteroarylene are selected from C.sub.1 to C.sub.12 alkyl and C.sub.1 to C.sub.12 alkoxy.
6. The organic electronic device according to claim 1, wherein for n=2 the compound has the chemical formula 2: ##STR00119##
7. The organic electronic device according to claim 1, wherein Ar.sup.1 is selected from at least one of the following: at least about 1 to about 5 heteroarylenes selected from 5 or 6 member rings, or about 1 to about 3 heteroarylenes selected from 5 or 6 member rings, or one 6 member heteroarylene ring; at least about 1 to 12 arylenes selected from 5 or 6 member rings, or at least about 2 to 10 arylenes selected from 5 or 6 member rings, or at least about 2 to 8 arylenes selected from 6 member rings or about 3 to about 6 arylenes selected from 6 member rings; at least 1 to 6 condensed 5 or 6 member rings of arylenes or heteroarylenes, or about 2 to about 4 condensed 5 or 6 member rings of arylenes or heteroarylenes, or 2 to about 4 condensed 5 or 6 member arylenes and one 5 or 6 member heteroarylene.
8. The organic electronic device according to claim 1, wherein Ar.sup.1 comprise at least about one group, or about one to about 4 groups, selected from phenyl, biphenyl, terpyhenyl, quarterphenyl, naphthyl, phenanthryl, dibenzofuranyl, dibenzothiophenyl, or a group selected from chemical structures D1 to D7: ##STR00120## ##STR00121## wherein Ar.sup.1 is bonded at“*” to Li, so that between Ar.sup.1 and L.sup.1 a single bond is formed; and wherein R.sup.5 and R.sup.6 are independently selected from C.sub.1 to C.sub.16 alkyl, or Ar.sup.2; and Ar.sup.4 and Ar.sup.5 are independently selected from C.sub.1 to C.sub.16 alkyl or substituted or unsubstituted C.sub.6 to C.sub.36 arylene, C.sub.2 to C.sub.25 heteroarylene, wherein the substituent of the substituted C.sub.6 to C.sub.36 arylene, C.sub.2 to C.sub.25 heteroarylene is selected from C.sub.1 to C.sub.12 alkyl, C.sub.1 to C.sub.12 alkoxy; and Ar.sup.6 is selected from H or phenyl.
9. The organic electronic device according to claim 1, wherein Ar.sup.1 is selected from the chemical structures F1 to F31, and is connected with L.sup.1 at “*” via a single bond: ##STR00122## ##STR00123## ##STR00124## ##STR00125## ##STR00126## ##STR00127## ##STR00128## ##STR00129##
10. The organic electronic device according to claim 1, wherein for the comp according to chemical formula 1: ##STR00130## wherein L.sup.1 is selected from the group of structures G1 to G13, wherein L.sup.1 is connected via a single bond to L.sup.2 at “.sup.*1”, and L.sup.1 is connected via a single bond to Ar.sup.1 at “.sup.*2”: a) for n=1 ##STR00131## ##STR00132## or b) for n=2 ##STR00133## wherein Ar.sup.7 is selected from C.sub.10 to C.sub.16 aryl, and R.sup.5 and R.sup.6 are independently selected from C.sub.1 to C.sub.16 alkyl, substituted or unsubstituted C.sub.6 to C.sub.36 arylene, or substituted or unsubstituted C.sub.2 to C.sub.25 heteroarylene.
11. The organic electronic device according to claim 1, wherein for the compound according to chemical formula 1: ##STR00134## X is O; R.sup.1, R.sup.2 are C.sub.1 to C.sub.4 alkyl; L.sup.1 is selected from a group of G1 to G13; L.sup.2 is a single bond; Ar.sup.1 is from a group of F1 to F31; n is 1 or 2; and wherein Ar.sup.1 is bonded at “*” to L.sup.1 via a single bond, L.sup.1 is connected via a single bond to L.sup.2 at “.sup.*1”, and L.sup.1 is connected via a single bond to Ar.sup.1 at “.sup.*2”; ##STR00135## ##STR00136## ##STR00137## ##STR00138## ##STR00139## ##STR00140## ##STR00141## ##STR00142## ##STR00143## ##STR00144## ##STR00145## ##STR00146## wherein R.sup.5 and R.sup.6 are independently selected from C.sub.1 to C.sub.16 alkyl, substituted or unsubstituted C.sub.6 to C.sub.36 arylene, or substituted or unsubstituted C.sub.2 to C.sub.25 heteroarylene, and wherein Ar.sup.7 is selected from C.sub.10 to C.sub.16 aryl.
12. Organic electronic device comprising at least one organic semiconductor layer, wherein the at least one organic semiconductor layer comprises a compound selected from the group of H1 to H60: ##STR00147## ##STR00148## ##STR00149## ##STR00150## ##STR00151## ##STR00152## ##STR00153## ##STR00154## ##STR00155## ##STR00156##
13. The organic electronic device according to claim 1, wherein the at least one organic semiconductor layer fulfils at least one of the following: is essentially non-emissive or non-emissive, free of covalently bound metal, free of ionically bound metal, wherein the metal is selected from the group consisting of group III to VI, rare earth and transition metal.
14. The organic electronic device according to claim 1, wherein the at least one organic semiconductor layer is arranged between a photoactive layer and a cathode layer, or between an emission layer or light-absorbing layer and the cathode layer, or the at least one organic semiconductor layer is an electron transport layer.
15. 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.
16. The organic electronic device according to claim 1, wherein the electronic device comprises the at least one organic semiconductor layer, at least one anode layer, at least one cathode layer and at least one emission layer, or the at least one organic semiconductor layer is arranged between the emission layer and the cathode layer.
17. 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.
18. A compound of formula 1 according to claim 1, wherein Ar.sup.1 that is selected from substituted or unsubstituted dibenzo[c,h]acridine, benzo[c]acridine, carbazole, indolo[3,2-a]carbazole, 1,3,5,2,4,6-triazatriphosphinine, and the following compounds are excluded: ##STR00157##
19. The organic electronic device according to claim 3, wherein L.sup.1 bonds via a single bond directly on a heteroarylene group of Ar.sup.1 and wherein the heteroarylene group comprises about 1 to about 3 N-atoms.
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:
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(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.
(12)
(13)
(14)
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(17)
(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 a 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. However, the present disclosure is not limited to the following examples.
(37) Preparation of Compounds of Formula 1
(38) Compounds of formula 1 may be prepared according to Route A, B, C and/or D.
(39) ##STR00091##
(40) ##STR00092##
(41) ##STR00093##
(42) ##STR00094##
(3′-bromo-[1,1′-biphenyl]-3-yl)dimethylphosphine Oxide
(43) ##STR00095##
(44) A flask was flushed with nitrogen and charged with 3,3′-dibromo-1,1′-biphenyl (50 g, 160 mmol), dimethylphosphine oxide (12.51 g, 160 mmol), Pd.sub.2(dba).sub.3 (2.93 g, 3.21 mmol), and xantphos (5.56 g, 9.62 mmol). A mixture of deaerated dioxane/THF (2:1, 480 mL) and trimethylamine (26 mL) were added and the reaction mixture was heated to reflux under a nitrogen atmosphere for 20 h. Subsequently, all volatiles have been removed in vacuo, the residue was dissolved in dichloromethane and washed with water three times. The organic phase was extracted with an aqueous sodium diethylcarbamodithioate solution three times and again with water two times. After drying over MgSO.sub.4, the organic phase was concentrated and the product was isolated by column chromatography (silica, dichloromethane to dichloromethane/methanol 99:1) to yield 18.5 g (37%) product. m/z=309 ([M].sup.+).
Dimethyl(3′-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-[1,1′-biphenyl]-3-yl)phosphine Oxide
(45) ##STR00096##
(46) A flask was flushed with nitrogen and charged with (3′-bromo-[1,1′-biphenyl]-3-yl)dimethylphosphine oxide (18.45 g, 59.7 mmol), 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane) (16.67 g, 65.6 mmol), Pd(dppf)Cl.sub.2 (0.87 g, 1.2 mmol), and potassium acetate (17.6 g, 179 mmol). Dry and deaerated DMF (185 mL) was added and the reaction mixture was heated to 80° C. under a nitrogen atmosphere for 20 h. Subsequently, all volatiles have been removed in vacuo, the residue was suspended in dichloromethane and washed with water three times. After drying over MgSO.sub.4, the organic phase was concentrated and filtered over a pad of Florisil. After rinsing with dichloromethane followed by dichloromethane/methanol 96:4, the filtrate was evaporated to dryness. The residue was triturated with MTBE and the resulting precipitate was collected by suction filtration and washed with additional MTBE to yield 13.6 g (64%) product. m/z=356 ([M].sup.+).
2-chloro-4-phenyl-6-(3-(9-phenyl-9H-fluoren-9-yl)phenyl)-1,3,5-triazine
(47) ##STR00097##
(48) A flask was flushed with nitrogen and charged with 2,4-dichloro-6-phenyl-1,3,5-triazine (18.0 g, 79.4 mmol), 4,4,5,5-tetramethyl-2-(3-(9-phenyl-9H-fluoren-9-yl)phenyl)-1,3,2-dioxaborolane (30 g, 67.5 mol), Pd(PPh.sub.3).sub.4(4.6 g, 3.98 mmol), and K.sub.2CO.sub.3 (27.5 g, 199 mmol). A mixture of deaerated toluene/THF/water (1:1:1, 660 mL) was added and the reaction mixture was heated to 65° C. under a nitrogen atmosphere for 6 h. Subsequently, all volatiles have been removed in vacuo, the residue was suspended in dichloromethane and washed with water three times. After drying over MgSO.sub.4, the organic phase was concentrated to a minimal amount and precipitation was induced by addition of acetonitrile. The precipitate was collected by suction filtration and washed with additional acetonitrile. Further purification was achieved by trituration with hot ethyl acetate. After suction filtration at room temperature and washing with additional ethyl acetate, 10 g (30%) product, m/z=508 ([M].sup.+).
2-([1,1′-biphenyl]-4-yl)-4-chloro-6-(9,9-diphenyl-9H-fluoren-4-yl)-1,3,5-triazine
(49) ##STR00098##
(50) Following the procedure described above using 2-([1,1′-biphenyl]-4-yl)-4,6-dichloro-1,3,5-triazine (25.5 g, 84.4 mmol), 2-(9,9-diphenyl-9H-fluoren-4-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (30 g, 67.5 mmol), Pd(dppf)Cl.sub.2 (3.09 g, 4.2 mmol), K.sub.2CO.sub.3 (29.1 g, 211 mmol), toluene/THF/water (1:1:1, 700 mL), and 3 h reaction time, 17.4 g (35%) product.
2-chloro-4-(3-chlorophenyl)-6-phenyl-1,3,5-triazine
(51) ##STR00099##
(52) Following the procedure described above using 2,4-dichloro-6-phenyl-1,3,5-triazine (35 g, 155 mmol), (3-chlorophenyl)boronic acid (19.4 g, 123.9 mmol), Pd(PPh.sub.3).sub.4(8.94 g, 7.7 mmol), K.sub.2CO.sub.3 (53.5 g, 387 mmol), toluene/THF/water (1:1:1, 1300 mL), and 3 h reaction time, 10.5 g (28%) product.
dimethyl(3′-(4-phenyl-6-(3-(9-phenyl-9H-fluoren-9-yl)phenyl)-1,3,5-triazin-2-yl)-[1,1′-biphenyl]-3-yl)phosphine Oxide
(53) ##STR00100##
(54) A flask was flushed with nitrogen and charged with 2-chloro-4-phenyl-6-(3-(9-phenyl-9H-fluoren-9-yl)phenyl)-1,3,5-triazine (5.43 g, 10.7 mmol), dimethyl(3′-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-[1,1′-biphenyl]-3-yl)phosphine oxide (4.0 g, 11.2 mmol), Pd(PPh.sub.3).sub.4(0.25 g, 0.21 mmol), and K.sub.2CO.sub.3 (2.95 g, 21.4 mmol). A mixture of deaerated THF/water (2:1, 53 mL) was added and the reaction mixture was heated to reflux under a nitrogen atmosphere for 18 h. After cooling down to room temperature, dichloromethane was added, the aqueous phase was removed and the organic phase was washed with water three times. Subsequently, the organic phase was extracted with an aqueous sodium diethylcarbamodithioate solution three times and again with water two times. After drying over MgSO.sub.4, the organic phase was concentrated to a minimal amount and precipitation was induced by addition of cyclohexane. The precipitate was collected by suction filtration and washed with additional cyclohexane. Further purification was achieved by column chromatography (silica, dichloromethane to dichloromethane/methanol 98:2) to yield 5.6 g (75%) product. m/z=724 ([M+Na].sup.+).
Dimethyl(3-(4-phenyl-6-(3-(9-phenyl-9H-fluoren-9-yl)phenyl)-1,3,5-triazin-2-yl)phenyl)phosphine Oxide
(55) ##STR00101##
(56) Following the procedure described above using 2-chloro-4-phenyl-6-(3-(9-phenyl-9H-fluoren-9-yl)phenyl)-1,3,5-triazine (4.3 g, 8.5 mmol), dimethyl(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)phosphine oxide (2.5 g, 8.9 mmol), Pd(dppf)Cl.sub.2 (0.12 g, 0.17 mmol), K.sub.2CO.sub.3 (2.34 g, 16.9 mmol), and THF/water (2:1, 42 mL), 4.95 g (93%) product. m/z=648 ([M+Na].sup.+).
(3′-(4-([1,1′-biphenyl]-4-yl)-6-(9,9-diphenyl-9H-fluoren-4-yl)-1,3,5-triazin-2-yl)-[1,1′-biphenyl]-3-yl)dimethylphosphine Oxide
(57) ##STR00102##
(58) Following the procedure described above using 2-([1,1′-biphenyl]-4-yl)-4-chloro-6-(9,9-diphenyl-9H-fluoren-4-yl)-1,3,5-triazine (5.73 g, 9.8 mmol), dimethyl(3′-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-[1,1′-biphenyl]-3-yl)phosphine oxide (3.67 g, 10.3 mmol), Pd(PPh.sub.3).sub.4(0.23 g, 0.2 mmol), K.sub.2CO.sub.3 (2.71 g, 19.6 mmol), and THF/water (2:1, 63 mL), 5.6 g (73%) product. m/z=800 ([M+Na].sup.+).
2-(3-chlorophenyl)-4-(9,9-diphenyl-9H-fluoren-4-yl)-6-phenyl-1,3,5-triazine
(59) ##STR00103##
(60) Following the procedure described above using 2-chloro-4-(3-chlorophenyl)-6-phenyl-1,3,5-triazine (5.05 g, 16.7 mmol), 2-(9,9-diphenyl-9H-fluoren-4-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (7.8 g, 17.6 mmol), Pd(PPh.sub.3).sub.4(0.39 g, 0.33 mmol), K.sub.2CO.sub.3 (4.6 g, 33.4 mmol), and THF/water (2:1, 84 mL), 8.2 g (84%) product.
4-yl)-6-phenyl-1,3,5-triazin-2-yl)-[1,1′-biphenyl]-3-yl)dimethylphosphine Oxide
(61) ##STR00104##
(62) A flask was flushed with nitrogen and charged with 2-(3-chlorophenyl)-4-(9,9-diphenyl-9H-fluoren-4-yl)-6-phenyl-1,3,5-triazine (4 g, 6.9 mmol), dimethyl(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)phosphine oxide (2.88 g, 10.3 mmol), chloro(crotyl)(2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl)palladium(II) (0.083 g, 0.13 mmol), and K.sub.3PO.sub.4 (2.9 g, 13.7 mmol). A mixture of deaerated THF/water (4:1, 50 mL) was added and the reaction mixture was heated to 45° C. under a nitrogen atmosphere for 2 h. After cooling down to room temperature, dichloromethane was added, the aqueous phase was removed and the organic phase was washed with water three times. Subsequently, the organic phase was extracted with an aqueous sodium diethylcarbamodithioate solution three times and again with water two times. After drying over MgSO.sub.4, the organic phase was evaporated to dryness. Purification of the crude product was achieved by column chromatography (silica, dichloromethane to dichloromethane/methanol 99:1) followed by precipitation from a concentrated dichloromethane solution by addition of methanol to yield 4.0 g (83%) product, m/z=724 ([M+Na].sup.+).
2-(3-(anthracen-9-yl)phenyl)-4,6-diphenyl-1,3,5-triazine
(63) ##STR00105##
(64) A flask was flushed with nitrogen and charged with 2-(3-bromophenyl)-4,6-diphenyl-1,3,5-triazine (50 g, 129 mmol), anthracen-9-ylboronic acid (31.5 g, 142 mmol), Pd(dppf)Cl.sub.2 (0.47 g, 0.64 mmol), and K.sub.2CO.sub.3 (35.6 g, 258 mmol). A mixture of deaerated toluene/ethanol (3:1, 670 mL) and deaerated water (130 mL) was added and the reaction mixture was heated to reflux under a nitrogen atmosphere for 18 h. After cooling down to room temperature, the precipitate was collected by suction filtration and washed with toluene, ethanol, and, subsequently, with water until the aqueous phase was pH neutral. After washing with methanol and drying, 56.4 g (90%) product were obtained.
2-(3-(10-bromoanthracen-9-yl)phenyl)-4,6-diphenyl-1,3,5-triazine
(65) ##STR00106##
(66) A flask was charged with 2-(3-(anthracen-9-yl)phenyl)-4,6-diphenyl-1,3,5-triazine (55 g, 113 mmol), NBS (24.2 g, 136 mmol), and chloroform (770 mL). The mixture was heated to 60° C. for 48 h. After cooling down to room temperature, the reaction mixture was extracted with water and dried over MgSO.sub.4. The organic phase was concentrated and n-hexane was added. The resulting precipitate was collected by suction filtration, washed with additional n-hexane and dried. 60.4 g (94.5%) product.
(3-(10-(3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)anthracen-9-yl)phenyl)dimethylphosphine Oxide
(67) ##STR00107##
(68) A flask was flushed with nitrogen and charged with 2-(3-(10-bromoanthracen-9-yl)phenyl)-4,6-diphenyl-1,3,5-triazine (15 g, 26.6 mmol), dimethyl(3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)phosphine oxide (8.2 g, 29.2 mmol), Pd(dppf)Cl.sub.2 (0.1 g, 0.13 mmol), and K.sub.2CO.sub.3 (7.3 g, 53 mmol). A mixture of deaerated toluene/ethanol (3:1, 300 mL) and deaerated water (30 mL) was added and the reaction mixture was heated to reflux under a nitrogen atmosphere for 18 h. All volatiles were removed in vacuo and the residue was dissolved in dichloromethane/water. The organic phase was additionally washed with water three times and then filtered over a pad of Florisil. The filtrate was concentrated and n-hexane was added. The resulting precipitate was purified by gel filtration (silica, chloroform to chloroform/methanol 97:3) to obtain 7.31 g (41%) product, m/z=660 ([M+Na].sup.+).
(4-(10-(3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)anthracen-9-yl)phenyl)dimethylphosphine Oxide
(69) ##STR00108##
(70) Following the procedure described above using dimethyl(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)phosphine oxide, 6.80 g (41%) product, m/z=660 ([M+Na].sup.+).
(71) General Procedure for Fabrication of Organic Electronic Devices
(72) Electron-only devices and OLEDs were prepared to demonstrate the technical benefit utilizing the compounds of formula 1 in an organic electronic device.
(73) Electron-Only Devices
(74) For electron-only devices (EOD), see Table 1 and 2, 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.
(75) Then, MgAg alloy (90:10 vol.-%) was deposited on the anode electrode to form a layer with a thickness of 30 nm.
(76) Then, LiQ was deposited on the MgAg layer to form a layer with a thickness of 1 nm.
(77) Then, an organic semiconductor layer was deposited on the LiQ layer to form an organic semiconductor layer with a thickness of 36 nm.
(78) In examples 1 to 6 (Table 1), the organic semiconductor layer consisted of compound of formula 1. In comparative example 1, MX1 [(3′-(4,6-diphenyl-1,3,5-triazin-2-yl)-[1,1′-biphenyl]-3-yl)diphenylphosphine oxide] was used instead, see Table 1.
(79) In example 7 (Table 2), 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 2.
(80) Then, LiQ was deposited to form a layer with a thickness of 1 nm.
(81) Then, MgAg alloy (90:10 vol.-%) was deposited on the LiQ layer to form a cathode electrode with a thickness of 30 nm.
(82) Bottom Emission Devices with an Evaporated Emission Layer
(83) For bottom emission devices—Example 8 and comparative example 3, 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.
(84) 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.
(85) Then, the organic semiconductor layer is formed by deposing a matrix compound and an alkali organic complex according to example 8 and comparative example 3 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 composition of the organic semiconductor layer can be seen in Table 3. In example 8 the matrix compound is a compound of formula 1. The thickness of the organic semiconductor layer is 36 nm.
(86) 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 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 with a thickness of 5 to 1000 nm. The thickness of the cathode electrode layer is 100 nm.
(87) Bottom Emission Devices with a Solution-Processed Emission Layer
(88) 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.
(89) 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.
(90) 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.
(91) Pn Junction Device as Model for an OLED Comprising at Least Two Emission Layers
(92) 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.
(93) 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.
(94) 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.
(95) 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.
(96) 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.
(97) 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).
(98) 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 with a thickness of 5 to 1000 nm. The thickness of the cathode electrode layer is 100 nm.
(99) 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.
(100) 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.
(101) In bottom emission devices, the emission is predominately Lambertian and quantified in percent external quantum efficiency (EQE). To determine the efficiency EQE in % the light output of the device is measured using a calibrated photodiode at 10 mA/cm2.
(102) In pn junction devices, the operating voltage is determined at 10 mA/cm.sup.2 as described for OLEDs above.
(103) Technical Effect of the Invention
(104) In Table 1 are shown the dipole moment, glass transition temperature Tg, rate onset temperature T.sub.RO of compound of formula 1 (examples 1 to 6) 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 measure of conductivity. The lower the operating voltage the higher the conductivity.
(105) In comparative example 1, MX1 has a glass transition temperature of 87° C. rate onset temperature of 234° C. The operating voltage is high at 1.8 V.
(106) In example 1, the glass transition temperature is improved to 120° C., the rate onset temperature is 229° C. and the operating voltage is reduced significantly to 1.4 V.
(107) In examples 2 to 6, the glass transition temperature is between 123 and 167° C., the rate onset temperature is between 229 and 294° C. and the operating voltage is significantly lower than in the comparative example.
(108) 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.
(109) TABLE-US-00001 TABLE 1 Glass transition temperature, rate onset temperature and operating voltage in electron-only devices Tg T.sub.RO Operating voltage Name Formula [° C.] [° C.] at 10 mA/cm.sup.2 [V] Comparative example 1 MX1
(110) In Table 2 are shown operating voltages of an organic semiconductor layer comprising a compound of formula 1 and alkali organic complex. The alkali organic complex is LI-1 (Lithium tetra(1H-pyrazol-1-yl)borate).
(111) In comparative example 2, the operating voltage is high at 0.5 V. In example 7, the operating voltage is reduced significantly to 0.3 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.
(112) TABLE-US-00002 TABLE 2 Electron-only devices of an organic semiconductor layer comprising a compound of formula 1 and an alkali organic complex. Table 2 vol.-% Alkali vol.-% alkali Operating Compound of compound of organic organic voltage at 10 mA/cm.sup.2 formula 1 formula 1 complex complex (V) Comparative MX1 70 LI-1 30 0.5 example 2 Example 7 MX5 70 LI-1 30 0.3
(113) In Table 3 are shown data for bottom emission OLEDs. In example 8, 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 3, the operating voltage is reduced significantly in example 8 compared to comparative example 3. Additionally, the lifetime is increased. Long lifetime is important for long-term stability of the organic electronic device.
(114) In summary, a beneficial effect of compound of formula ion operating voltage and lifetime is observed when used in the electron transport layer.
(115) TABLE-US-00003 TABLE 3 OLED performance of a first electron transport layer comprising a compound of formula 1 and an alkali organic complex Compound vol.-% Alkali vol.-% alkali LT97 at of compound of organic organic Thickness Operating voltage cd/A efficiency at 10 mA/cm.sup.2 formula 1 formula 1 complex complex ETL1/nm at 10 mA/cm.sup.2 (V) 10 mA/cm.sup.2 (cd/A) [h] Comparative MX1 70 LI-1 30 36 3.7 6.1 133 example 3 Example 8 MX5 70 LI-1 30 36 3.5 5.9 171
(116) 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.