ORGANIC MOLECULES FOR OPTOELECTRONIC DEVICES

Abstract

The disclosure relates to an organic molecule, in particular for the application in optoelectronic devices. According to the disclosure, the organic molecule has a structure represented by Formula I:

##STR00001##

In Formula 1, R.sup.I, R.sup.II, R.sup.III, R.sup.IV, R.sup.V, R.sup.VI, R.sup.VII, R.sup.VIII, R.sup.IX, R.sup.X and R.sup.XI are each independently selected from the group consisting of: hydrogen, deuterium, halogen, C.sub.1-C.sub.12-alkyl, wherein optionally one or more hydrogen atoms are each independently substituted by R.sup.5, C.sub.6-C.sub.18-aryl, wherein optionally one or more hydrogen atoms are each independently substituted by R.sup.5, and C.sub.3-C.sub.15-heteroaryl. R.sup.5 is independently selected from the group consisting of: hydrogen, deuterium, C.sub.1-C.sub.12-alkyl, and C.sub.6-C.sub.18aryl, wherein optionally one or more hydrogen atoms are each independently substituted by C.sub.1-C.sub.5-alkyl substituents; T, V, W, and X are each independently selected from the group consisting of: C.sub.1-C.sub.12-alkyl, and C.sub.6-C.sub.18-aryl, wherein optionally one or more hydrogen atoms are each independently substituted by C.sub.1-C.sub.5-alkyl substituents.

Claims

1. An organic molecule, comprising a structure represented by Formula I: ##STR00053## Formula I wherein in Formula I, R.sup.I, R.sup.II, R.sup.III, R.sup.IV, R.sup.V, R.sup.VI, R.sup.VII, R.sup.VIII, R.sup.IX, R.sup.X and R.sup.XI are each independently selected from the group consisting of: hydrogen, deuterium, halogen, C.sub.1-C.sub.12-alkyl, C.sub.6-C.sub.18-aryl, C.sub.3-C.sub.15-heteroaryl, and combinations thereof, wherein optionally one or more hydrogen atoms of C.sub.1-C.sub.12-alkyl, C.sub.6-C.sub.18-aryl, and C.sub.3-C.sub.15-heteroaryl are each independently substituted by R.sup.5, wherein R.sup.5 is at each occurrence independently selected from the group consisting of: hydrogen, deuterium, C.sub.1-C.sub.12-alkyl, C.sub.6-C.sub.18-aryl, and combinations thereof, wherein optionally one or more hydrogen atoms of C.sub.1-C.sub.12-alkyl and C.sub.6-C.sub.18-aryl are each independently substituted by C.sub.1-C.sub.5-alkyl substituents and wherein T, V, W, and X are each independently selected from the group consisting of: C.sub.1-C.sub.12-alkyl, C.sub.6-C.sub.18-aryl, and combinations thereof, and wherein optionally one or more hydrogen atoms of C.sub.1-C.sub.12-alkyl and C.sub.6-C.sub.18-aryl are each independently substituted by C.sub.1-C.sub.5-alkyl substituents.

2. The organic molecule according to claim 1, wherein T, V, W, and/or X is each independently selected from the group consisting of: .sup.tBu, Ph, and combinations thereof, and wherein Ph is optionally substituted with one or more substituents independently selected from the group consisting of Me, .sup.iPr and .sup.tBu.

3. The organic molecule according to claim 1, comprising a structure represented by Formula I-1 or Formula I-2: ##STR00054##

4. The organic molecule according to claim 1, wherein R.sup.I, R.sup.II, R.sup.III, R.sup.IV, R.sup.V, R.sup.VI, R.sup.VII, R.sup.VIII, R.sup.IX, R.sup.X and R.sup.XI are each independently selected from the group consisting of: hydrogen, deuterium, halogen, C.sub.1-C.sub.12-alkyl, C.sub.6-C.sub.18-aryl, C.sub.3-C.sub.15-heteroaryl, and combinations thereof wherein optionally one or more hydrogen atoms of C.sub.1-C.sub.12-alkyl, C.sub.6-C.sub.18-aryl, C.sub.3-C.sub.15-heteroaryl are each independently substituted by C.sub.1-C.sub.6-alkyl substituents, or C.sub.6-C.sub.18-aryl substituents.

5. The organic molecule according to claim 1, wherein R.sup.I, R.sup.II, R.sup.III, R.sup.IV, R.sup.V, R.sup.VI, R.sup.VII, R.sup.VIII, R.sup.IX, R.sup.X and R.sup.XI are each independently selected from the group consisting of: hydrogen, deuterium, halogen, Me, .sup.iPr, .sup.tBu, Ph, carbazole and combinations thereof, wherein Ph is optionally substituted with one or more substituents independently selected from the group consisting of Me, .sup.iPr, .sup.tBu, cyclohexyl and Ph, and wherein carbazole is optionally substituted with one or more substituents independently selected from the group consisting of Me, .sup.iPr, .sup.tBu, cyclohexyl and Ph.

6. The organic molecule according to claim 1, wherein the organic molecule comprises a structure selected from the group consisting of Formula Ia to Formula In: ##STR00055## ##STR00056## ##STR00057## ##STR00058##

7. The organic molecule according to claim 1, comprising a structure selected from the group consisting of Formula IIa to Formula IIn: ##STR00059## ##STR00060## ##STR00061## ##STR00062##

8. The organic molecule according to claim 1, wherein R.sup.XI is selected from the group consisting of: hydrogen, deuterium, halogen, Me, .sup.iPr, .sup.tBu, Ph carbazole, and combinations thereof, and wherein Ph is optionally substituted with one or more substituents independently selected from the group consisting of Me, .sup.iPr, .sup.tBu, cyclohexyl and Ph, and wherein carbazole is optionally substituted with one or more substituents independently selected from the group consisting of Me, .sup.iPr, .sup.tBu, cyclohexyl and Ph.

9. The organic molecule according to claim 1, wherein R.sup.XI is selected from the group consisting of: hydrogen, deuterium, Me, .sup.iPro, .sup.tBu, cyclohexyl, Ph, carbazole, and combinations thereof, and wherein carbazole is optionally substituted with one or more substituents independently selected from the group consisting of .sup.tBu and Ph.

10. The organic molecule according to claim 1, wherein R.sup.XI is hydrogen or Me.

11. An optoelectronic device comprising the organic molecule according to claim 1, wherein the optoelectronic device is one or more selected from the group consisting of: organic light-emitting diodes (OLEDs), light-emitting electrochemical cells, OLED-sensors, organic diodes, organic solar cells, organic transistors, organic field-effect transistors, organic lasers, and down-conversion elements.

12. A composition, comprising: (a) the organic molecule according to claim 1, as a first emitter and/or a first host, and (b) a second emitter and/or a second host material, which differs from the organic molecule, and (c) optionally, a dye and/or a solvent.

13. An optoelectronic device, comprising the composition according to claim 12, wherein the optoelectronic device is one or more selected from the group consisting of organic light-emitting diodes (OLEDS), light-emitting electrochemical cells, OLED-sensors, organic diodes, organic solar cells, organic transistors, organic field-effect transistors, organic lasers, and down-conversion elements.

14. The optoelectronic device according to claim 11, comprising: a substrate, an anode and a cathode facing each other, wherein the anode or the cathode is disposed on the substrate, and a light-emitting layer, which is between the anode and the cathode and which comprises the organic molecule.

15. A method for producing an optoelectronic device, the method comprising depositing the organic molecule according to claim 1 by a vacuum evaporation method or from a solution.

16. The optoelectronic device according to claim 13, comprising: a substrate, an anode and a cathode facing each other, wherein the anode or the cathode is disposed on the substrate, and a light-emitting layer, which is between the anode and the cathode and which comprises the composition.

17. A method for producing an optoelectronic device, the method comprising depositing the composition according to claim 12 by a vacuum evaporation method or from a solution.

Description

EXAMPLES

[0190] ##STR00013## ##STR00014##

##STR00015##

[0191] E1 (1.00 equivalent), aniline (E2 2.20 equivalents), tris(dibenzylideneacetone)dipalladium Pd.sub.2(dba).sub.3 (0.01 equivalents, CAS: 51364-51-3), tri-tert-butyl-phosphine P(.sup.tBu).sub.3 (0.04 equivalents, CAS: 13716-12-6) and sodium tert-butoxide NaO.sup.tBu (4.20 equivalents, CAS: 865-48-5) are stirred under nitrogen atmosphere in toluene at 90° C. After cooling down to room temperature (rt) the reaction mixture is extracted with toluene and brine and the phases are separated. The combined organic layers are dried over MgSO.sub.4 and then the solvent is removed under reduced pressure. The crude product obtained is purified by recrystallization or column chromatography and 11 is obtained as a solid.

##STR00016##

[0192] I1 (1.00 equivalents), E3 (2.10 equivalents), tris(dibenzylideneacetone)dipalladium Pd.sub.2(dba).sub.3 (0.01 equivalents; CAS: 51364-51-3), tri-tert-butyl-phosphine P(.sup.tBu).sub.3 (0.04 equivalents, CAS: 13716-12-6) and sodium tert-butoxide NaO.sup.tBu (4.00 equivalents, CAS: 865-48-5) are stirred under nitrogen atmosphere in toluene at 110° C. After cooling down to room temperature (rt), the reaction mixture is extracted with toluene and brine and the phases are separated. The combined organic layers are dried over MgSO.sub.4 and then the solvent is removed under reduced pressure. The crude product obtained is purified by recrystallization or column chromatography and I2 is obtained as a solid.

##STR00017##

[0193] I2 (1.00 equivalent) is stirred under nitrogen atmosphere in .sup.tBu-benzene at 40° C. Tert-butyllithium (.sup.tBuLi, 2.20 equivalents, CAS 594-19-4) is added dropwise and the reaction is heated to 50° C. The lithiation is quenched by slowly adding trimethyl borate (6 equivalents, CAS 121-43-7) at room temperature. After heating the reaction mixture to 60° C. for 2 h, the reaction mixture is cooled down to room temperature. Water is added and the mixture is stirred for another 2 h. After extraction with ethyl acetate, the organic phase is dried over MgSO.sub.4 and the solvent is removed under reduced pressure. The crude product obtained is purified by recrystallization or column chromatography and 13 is obtained as a solid.

##STR00018##

[0194] I3 (1.00 equivalent) is stirred und nitrogen atmosphere in chlorobenzene. N,N-diisopropylethylamine (10.0 equivalents, CAS 7087-68-5) and aluminum chloride (AlCl.sub.3, 10.0 equivalents, CAS 7446-70-0) are added and the reaction mixture is heated to 120° C. After 60 min, N,N-Diisopropylethylamine (5.00 equivalents, CAS 7087-68-5) and aluminum chloride (AlCl.sub.3, 5.00 equivalents, CAS 7446-70-0) are added and the reaction mixture is stirred for 1.5 h. After cooling down to room temperature, the reaction mixture is extracted between DCM and water. The organic phase is dried over MgSO.sub.4 and the solvent is removed under reduced pressure. The crude product P1 can be further purified by recrystallization or column chromatography.

##STR00019##

[0195] Under nitrogen atmosphere E4 (1.00 equivalent), E5 (1.50 equivalents), tris(dibenzylideneacetone)-dipalladium(0) (0.005 equivalents, CAS 51364-51-3), 2-dicyclohexylphosphino-2′,4′,6′-tri-isopropyl-1,1′-biphenyl (0.02 equivalents, X-Phos, CAS 564483-18-7) and tribasic potassium phosphate (2.00 equivalents, CAS 7778-53-2) were suspended in toluene/water (4:1 by volume). The mixture was heated to 110° C. until completion of the reaction. After cooling down to room temperature, the phases were separated and the aqueous phase extracted with ethyl acetate. The combined organic layers were stirred at rt for 15 min with a 1:1:1 mixture of Charcoal/Celite® (kieselgur)/MgSO.sub.4, filtered and concentrated. The crude product was purified by recrystallization to yield E2.

Cyclic Voltammetry

[0196] Cyclic voltammograms are measured from solutions having concentration of 10.sup.−3 mol/L of the organic molecules in dichloromethane or a suitable solvent and a suitable supporting electrolyte (e.g. 0.1 mol/L of tetrabutylammonium hexafluorophosphate). The measurements are conducted at room temperature under nitrogen atmosphere with a three-electrode assembly (Working and counter electrodes: Pt wire, reference electrode: Pt wire) and calibrated using FeCp.sub.2/FeCp.sub.2.sup.+ as internal standard. The HOMO data was corrected using ferrocene as internal standard against a saturated calomel electrode (SCE).

Density Functional Theory Calculation

[0197] Molecular structures are optimized employing the BP86 functional and the resolution of identity approach (RI). Excitation energies are calculated using the (BP86) optimized structures employing Time-Dependent DFT (TD-DFT) methods. Orbital and excited state energies are calculated with the B3LYP functional. Def2-SVP basis sets and a m4-grid for numerical integration are used. The Turbomole program package is used for all calculations.

Photophysical Measurements

[0198] Sample pretreatment: Spin-coating

[0199] Apparatus: Spin150, SPS euro.

[0200] The sample concentration is 10 mg/ml, dissolved in a suitable solvent.

[0201] Program: 1) 3 s at 400 U/min; 2) 20 s at 1000 U/min at 1000 Upm/s; 3) 10 s at 4000 U/min at 1000 Upm/s. After coating, the films are dried at 70° C. for 1 min.

Photoluminescence Spectroscopy and Time-Correlated Single-Photon Counting (TCSPC)

[0202] Steady-state emission spectroscopy is measured by a Horiba Scientific, Modell FluoroMax-4 equipped with a 150 W Xenon-Arc lamp, excitation- and emissions monochromators and a Hamamatsu R928 photomultiplier and a time-correlated single-photon counting option. Emissions and excitation spectra are corrected using standard correction fits.

[0203] Excited state lifetimes are determined employing the same system using the TCSPC method with FM-2013 equipment and a Horiba Yvon TCSPC hub.

[0204] Excitation sources:

[0205] NanoLED 370 (wavelength: 371 nm, puls duration: 1.1 ns)

[0206] NanoLED 290 (wavelength: 294 nm, puls duration: <1 ns)

[0207] SpectraLED 310 (wavelength: 314 nm)

[0208] SpectraLED 355 (wavelength: 355 nm).

[0209] Data analysis (exponential fit) is done using the software suite DataStation and DAS6 analysis software. The fit is specified using the chi-squared-test.

Photoluminescence Quantum Yield Measurements

[0210] For photoluminescence quantum yield (PLQY) measurements an Absolute PL Quantum Yield Measurement C9920-03G system (Hamamatsu Photonics) is used. Quantum yields and CIE coordinates are determined using the software U6039-05 version 3.6.0.

[0211] Emission maxima are given in nm, quantum yields ϕ in % and CIE coordinates as x,y values.

[0212] PLOY is determined using the following protocol:

[0213] Quality assurance: Anthracene in ethanol (known concentration) is used as reference

[0214] Excitation wavelength: the absorption maximum of the organic molecule is determined and the molecule is excited using this wavelength

[0215] Measurement

[0216] Quantum yields are measured, for sample, of solutions or films under nitrogen atmosphere. The yield is calculated using the equation:

[00001]${\Phi }_{PL}=\frac{n_{\mathrm{photon}},\mathrm{emited}}{n_{\mathrm{photon}},\mathrm{absorbed}}=\frac{\int \frac{\lambda }{\mathrm{hc}}\left[{\mathrm{Int}}_{\mathrm{emitted}}^{\mathrm{sample}}\left(\lambda \right)-{\mathrm{Int}}_{\mathrm{absorbed}}^{\mathrm{sample}}\left(\lambda \right)\right]d\lambda }{\int \frac{\lambda }{\mathrm{hc}}\left[{\mathrm{Int}}_{\mathrm{emitted}}^{\mathrm{reference}}\left(\lambda \right)-{\mathrm{Int}}_{\mathrm{absorbed}}^{\mathrm{reference}}\left(\lambda \right)\right]d\lambda }$

[0217] wherein n.sub.photon denotes the photon count and Int. denotes the intensity.

Production and Characterization of Optoelectronic Devices

[0218] Optoelectronic devices, in particular OLED devices, including organic molecules according to the disclosure can be produced via vacuum-deposition methods. If a layer contains more than one compound, the weight-percentage of one or more compounds is given in %. The total weight-percentage values amount to 100%, thus if a value is not given, the fraction of this compound equals to the difference between the given values and 100%.

[0219] The not fully optimized OLEDs are characterized using standard methods and measuring electroluminescence spectra, the external quantum efficiency (in %) in dependency on the intensity, calculated using the light detected by the photodiode, and the current. The OLED device lifetime is extracted from the change of the luminance during operation at constant current density. The LT50 value corresponds to the time, where the measured luminance decreased to 50% of the initial luminance, analogously LT80 corresponds to the time point, at which the measured luminance decreased to 80% of the initial luminance, LT 95 to the time point, at which the measured luminance decreased to 95% of the initial luminance etc.

[0220] Accelerated lifetime measurements are performed (e.g. applying increased current densities). For example, LT80 values at 500 cd/m.sup.2 are determined using the following equation:

[00002]$\mathrm{LT}80\left(500\frac{\mathrm{cd}}{m^2}\right)=\mathrm{LT}80\left(L_0\right){\left(\frac{L_0}{500\frac{\mathrm{cd}}{m^2}}\right)}^{1.6}$

[0221] wherein L.sub.0 denotes the initial luminance at the applied current density.

[0222] The values correspond to the average of several pixels (typically two to eight), and the standard deviation between these pixels is given.

[0223] HPLC-MS

[0224] HPLC-MS analysis is performed on an HPLC by Agilent (1100 series) with MS-detector (Thermo LTQ XL).

[0225] For example, a typical HPLC method is as follows: a reverse phase column 4.6 mm×150 mm, particle size 3.5 μm from Agilent (ZORBAX Eclipse Plus 95 Å C18, 4.6×150 mm, 3.5 μm HPLC column) is used in the HPLC. The HPLC-MS measurements are performed at room temperature (rt) following gradients

TABLE-US-00001 Flow rate [ml/min] Time [min] A[%] B[%] C[%] 2.5 0 40 50 10 2.5 5 40 50 10 2.5 25 10 20 70 2.5 35 10 20 70 2.5 35.01 40 50 10 2.5 40.01 40 50 10 2.5 41.01 40 50 10

[0226] using the following solvent mixtures:

TABLE-US-00002 Solvent A: H2O (90%) MeCN (10%) Solvent B: H2O (10%) MeCN (90%) Solvent C: THF (50%) MeCN (50%)

[0227] An injection volume of 5 μL from a solution with a concentration of 0.5 mg/mL of the analyte is taken for the measurements.

[0228] Ionization of the probe is performed using an atmospheric pressure chemical ionization (APCI) source either in positive (APCI+) or negative (APCI−) ionization mode.

Example 1

[0229] ##STR00020##

[0230] Example 1 was synthesized according to

[0231] AAV5 (44% yield) using 4-tert-butyl-3-chloroaniline (CAS 52756-36-2) as E4 and phenylboronic acid (CAS 98-80-6) as E5;

[0232] AAV1 (52% yield) using 4-chloro-3,5-dibromotoluene (CAS 202925-05-1) as E1;

[0233] AAV2 (69% yield) using 1-bromo-3,5-di-tert-butylbenzene (CAS 22385-77-9) as E3;

[0234] AAV3 (26% yield) and

[0235] AAV4 (15% yield).

[0236] MS (HPLC-MS), m/z (retention time): 924.4 (8.75 min)

[0237] The emission maximum of example 1 (2% by weight in PMMA) is at 461 nm, the full width at half maximum (FWHM) is 0.16 eV, and the CIEy coordinate is 0.11. The photoluminescence quantum yield (PLQY) is 77%.

Example D1

[0238] Example 1 was tested in the OLED D1, which was fabricated with the following layer structure:

TABLE-US-00003 Layer # Thickness D1 9 100 nm Al 8  2 nm Liq 7  11 nm NBPhen 6  20 nm MAT1 5  20 nm MAT2 (98%):Example 1 (2%) 4  10 nm MAT3 3  50 nm MAT4 2  7 nm HAT-CN 1  50 nm ITO Substrate Glass [00021][00022][00023][00024]

[0239] OLED D1 yielded an external quantum efficiency (EQE) at 1000 cd/m.sup.2 of 11.1%. The emission maximum is at 465 nm with a FWHM of 28 nm at 3.7 V. The corresponding CIEx value is 0.13 and the CIEy value is 0.10. A LT95-value at 1200 cd/m.sup.2 of 12 h was determined.

Additional Examples of Organic Molecules of the Disclosure

[0240] ##STR00025## ##STR00026## ##STR00027## ##STR00028## ##STR00029## ##STR00030## ##STR00031## ##STR00032## ##STR00033## ##STR00034## ##STR00035## ##STR00036## ##STR00037## ##STR00038## ##STR00039## ##STR00040## ##STR00041## ##STR00042## ##STR00043## ##STR00044## ##STR00045## ##STR00046## ##STR00047## ##STR00048## ##STR00049## ##STR00050## ##STR00051## ##STR00052##