An organic porphyrin compound, a preparation method and application thereof

Abstract

The application discloses an organic porphyrin compound and a preparation method and application thereof, the porphyrin compound has a structure as shown in a general formula (I), and aromatic amine groups are introduced on 1 and 2 carbon atoms of a porphyrin skeleton through C-N coupling reaction.By introducing the aromatic amine groups on the porphyrin skeleton, the application limits the rotation of the aromatic ring, greatly improves the luminous efficiency of the compound, and adopts cheap copper single elements or copper compounds as catalysts, so that the compound synthesis cost is low, the preparation method is simple, and the application has a good commercial application prospect in the field of electroluminescent devices.

Description

Technical Field

[0001] This invention relates to the field of organic light-emitting materials, specifically to a novel organic pyrrole compound, its preparation method, and its application. Background Technology

[0002] Organic light-emitting diodes (OLEDs) are widely used in display and lighting fields due to their advantages such as low power consumption, high efficiency, fast response speed, and wide viewing angle. For example, they are used as displays in electronic devices such as mobile phones, tablets, and televisions. Currently, most commercially available OLED devices use phosphorescent transition metal complexes as their luminescent materials. However, due to the use of precious metal elements, the preparation cost of these materials is high, and phosphorescent transition metal complexes are difficult to achieve high-efficiency, high-purity blue emission, which to some extent limits the development of inexpensive and high-efficiency OLED devices. Thermally activated delayed fluorescence (TADF) materials, as third-generation OLED luminescent materials, can effectively utilize triplet excitons and achieve efficient electroluminescence, just like phosphorescent materials. Furthermore, these materials are simple to synthesize and have low preparation costs. In addition, TADF compounds are also widely used in organic photovoltaic cells, organic light-emitting field-effect transistors, organic lasers, and organic sensors.

[0003] Pyrrole cores, as strong electron donors, have wide applications and development in the field of optoelectronic materials. These materials usually exhibit fluorescence emission characteristics, but fluorescent materials cannot effectively utilize electrogenerated triplet excitons in organic optoelectronic devices, resulting in low efficiency of related devices (such as OLED devices). Summary of the Invention

[0004] Objectives of the invention: The first objective of this invention is to provide a novel organic pyrrole compound with low cost and high luminescence efficiency; the second objective of this invention is to provide a method for preparing the organic pyrrole compound, which is simple to operate, has low raw material cost, and high synthesis efficiency; the third objective of this invention is to provide applications of the organic pyrrole compound.

[0005] Technical solution: To achieve the above objectives, the present invention provides an organic pyrrole compound represented by the following general formula (I):

[0006]

[0007] Among them, Ar 1 and Ar 2 It is either not replaced or replaced by one or more E 1 The substituted heteroaromatic ring group containing at least one N, said E 1 Selected from H, F, Cl, Br, I, D, CN, NO2, CF3, OE 2 Si(E) 2 3. N(E)2 2. B(E) 2 2. One of the following: a straight-chain alkane group, a cycloalkane group, or an aromatic hydrocarbon group, and a substituted or unsubstituted aromatic cycloalloy or heteroaromatic group containing 5 to 10 ring atoms, wherein E 2 It is one of H, D, an aliphatic alkane group containing 1 to 10 carbon atoms, an aromatic hydrocarbon group, and a substituted or unsubstituted aromatic cyclic group or heteroaromatic group containing 5 to 10 ring atoms; Ar 3 For not being replaced or by one or more E 3 The substituted benzene ring, the E 3 Selected from H, F, Cl, Br, I, D, and alkyl chains (straight or branched) containing 1 to 18 carbons.

[0008] Preferably, the Ar 1 and Ar 2 Choose any one of the following general formulas C1 to C5:

[0009]

[0010] Wherein, R1 and R2 represent the benzene ring surrounded by one or more H, F, Cl, Br, I, D, CN, NO2, CF3, B(OR) atoms. 2 )2、Si(R 2 3. Straight-chain alkane groups, alkane ether groups, alkane thioether groups or branched-chain alkane groups or cycloalkane groups containing 1 to 10 carbon atoms, alkane ether groups or alkane thioether groups containing 3 to 10 carbon atoms, aryl substitutions containing 6 to 10 carbon atoms; dashed lines indicate connections in the form of single bonds.

[0011] The organic pyrrole compound has the following structural formula:

[0012]

[0013] The present invention also includes a method for preparing the said organic pyrrole compound, comprising the following steps:

[0014]

[0015] A brominated pyrrole compound reacts with one or more secondary aromatic amines via a coupling reaction catalyzed by elemental copper or copper compounds to generate an organic pyrrole compound (I), which is then purified by column chromatography to obtain the pure product.

[0016] The present invention also includes the use of the organic pyrrole compound in organic electronic devices, wherein the organic electronic devices are organic light-emitting diodes, organic photovoltaic cells, organic light-emitting cells, organic field-effect transistors, organic light-emitting field-effect transistors, organic lasers, or organic sensors.

[0017] The amount of the organic pyrrole compound added is 10%.

[0018] The present invention also includes an organic electronic device comprising the aforementioned organic pyrrole compound.

[0019] The amount of the organic pyrrole compound added is 10%.

[0020] This invention starts from the molecular design strategy of thermally activated delayed fluorescence materials. By introducing strong electron-donating aromatic amine groups on the 1st and 2nd carbon atoms of the pyrrole skeleton, a space charge transfer channel from aromatic amine to cyano group is constructed and efficient thermally activated delayed fluorescence emission is achieved.

[0021] Beneficial effects: Compared with the prior art, the advantages of the present invention are: (1) By introducing aromatic amine groups on the pyrrole skeleton, the rotation of the aromatic ring is restricted, which greatly improves the luminescence efficiency of the compound; (2) The present invention uses inexpensive copper element or copper compound as catalyst, the compound synthesis cost is low, the preparation method is simple, and it has good commercial application prospects in the field of electroluminescent devices. Attached Figure Description

[0022] Figure 1 Absorption and emission spectra of the compound obtained in Example 1 in toluene solvent;

[0023] Figure 2 Emission spectrum of the compound obtained in Example 1 in a thin film;

[0024] Figure 3 Mass spectra of the compounds obtained in Example 1;

[0025] Figure 4 The 1H NMR spectrum of the compound obtained in Example 1;

[0026] Figure 5 Mass spectra of the compounds obtained in Example 2;

[0027] Figure 6 Mass spectra of the compounds obtained in Example 3;

[0028] Figure 7 Mass spectra of the compounds obtained in Example 4;

[0029] Figure 8 General structural formula of organic pyrrole compounds. Detailed Implementation

[0030] The technical solution of the present invention will be further described below, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0031] Example 1: Synthesis of Organic Pyrrole Compound 1

[0032] (1) Synthesis of precursor compound CN-1:

[0033] Weigh p-cyanoaniline (2.36 g, 20 mmol) and p-tert-butylbenzaldehyde (3.24 g, 20 mmol) into a dry two-necked flask. Add 10 mL of acetic acid and 10 mL of toluene. Heat and stir at 50 °C for 1 hour. Add ferric p-toluenesulfonate (683.3 mg, 1.2 mmol), and then slowly add 2,3-butanedione (860.1 mg, 10 mmol) using a syringe. Stir the reaction mixture at 50 °C overnight. After the reaction is complete, cool the reaction solution to room temperature, filter using a Buchner funnel, and wash the residue with acetic acid. The residue is the target compound CN-1. The yield is 62%. 1 H NMR (400MHz, CDCl3) δ=7.65 (d, J=8.6Hz, 4H), 7.36 (d, J=8.6Hz, 5H), 7.30 (d, J=8.4Hz, 7H), 7.12 (d, J=8.4Hz, 4H), 6.44 (s, 2H), 1.32 (s, 18H). MS calculated for C 40 N4H 36 :572.76.Found:572.56.

[0034]

[0035] (2) Synthesis of the precursor compound CN-Br:

[0036] The precursor compound CN-1 (57.3 mg, 0.1 mmol) was weighed into a dry two-necked flask, and 5 mL of dichloromethane was added. A dichloromethane solution of NBS (35.6 mg, 5 mL) was slowly added dropwise. The reaction mixture was stirred at room temperature for 15 minutes, and the color of the reaction solution turned red. The reaction solution was extracted with dichloromethane solvent and deionized water (3 × 50 mL). The organic phase was collected, and the solvent was removed by rotary evaporation. The target compound CN-Br was purified by column chromatography using petroleum ether and dichloromethane (volume ratio 2:1). The yield was 82%. 1 H NMR (400MHz, CDCl3) δ=7.61 (d, J=8.7Hz, 4H), 7.36 (d, J=8.8Hz, 4H), 7.30 (d, J=8.6Hz, 4H), 7.09 (d, J=8.7Hz, 4H), 1.30 (s, 18H). MS calculated for C 40 H 34 Br2N4:730.6.Found:730.1.

[0037]

[0038] (3) Synthesis of organic pyrrole compound 1:

[0039] Precursor compound CN-Br (36.5 mg, 0.05 mmol), 3,6-di-tert-butylcarbazole (29.3 mg, 0.105 mmol), copper powder (20.0 mg, 0.315 mmol), and potassium carbonate (29.0 mg, 0.21 mmol) were placed in a 25 mL double-necked flask. 10 mL of dry o-dichlorobenzene solvent was added under a nitrogen atmosphere, and the mixture was heated and stirred at 180 °C for 3 days. The reaction was monitored by thin-layer chromatography. The reaction was stopped after the reactants were consumed, and the reaction solution was cooled to room temperature. The o-dichlorobenzene solvent was removed by rotary evaporation. The target compound CN-Cz, or organopyrrole compound 1, was obtained by column chromatography, with petroleum ether and dichloromethane (volume ratio 2:1) as the eluent. The product was a white powder with a yield of 42%. 1 H NMR (400MHz, CDCl3) δ = 8.00 (m, 4H), 7.22 (m, 4H), 6.96-6.88 (m, 8H), 6.76 (d, J =8.7Hz, 4H), 6.70 (d, J = 8.6Hz, 4H), 6.53 (d, J = 8.7Hz, 4H), 1.48-1.40 (m, 54H). MS calculated for C 80 H 82 N6: 1127.58. Found: 1127.9.

[0040]

[0041] Example 2: Synthesis of Organic Pyrrole Compound 2

[0042] (1) and (2) are the same as in Example 1.

[0043] (3) Synthesis of organic pyrrole compound 2:

[0044] Precursor compound CN-Br (36.5 mg, 0.05 mmol), phenoxazine (27.5 mg, 0.15 mmol), copper powder (20.0 mg, 0.315 mmol), and potassium carbonate (29.0 mg, 0.21 mmol) were placed in a 25 mL double-necked flask. 5 mL of dry o-dichlorobenzene was added under a nitrogen atmosphere, and the mixture was stirred at 180 °C for 2 days. The reaction was monitored by thin-layer chromatography. The reaction was stopped after the reactants were consumed, and the reaction solution was cooled to room temperature. The o-dichlorobenzene solvent was removed by rotary evaporation. The target compound 2, or organopyrrole compound 2, was obtained by column chromatography, with petroleum ether and dichloromethane (volume ratio 2:1) as the eluent. The product was a white powder with a yield of 53%. MS calculated for C64 H 50 N6O2: 934.40. Found: 934.77.

[0045]

[0046] Example 3: Synthesis of Organic Pyrrole Compound 3

[0047] (1) and (2) are the same as in Example 1.

[0048] (3) Synthesis of organic pyrrole compound 3:

[0049] Precursor compound CN-Br (36.5 mg, 0.05 mmol), diphenylamine (25.4 mg, 0.15 mmol), copper powder (20.0 mg, 0.315 mmol), and potassium carbonate (29.0 mg, 0.21 mmol) were placed in a 25 mL double-necked flask. 5 mL of dry o-dichlorobenzene was added under a nitrogen atmosphere, and the mixture was stirred at 180 °C for 2 days. The reaction was monitored by thin-layer chromatography. The reaction was stopped after the reactants were consumed, and the reaction solution was cooled to room temperature. The o-dichlorobenzene solvent was removed by rotary evaporation. The target compound 3, an organopyrrole compound 3, was obtained by column chromatography, with petroleum ether and dichloromethane (volume ratio 1:1) as the eluent. The product was a white powder with a yield of 45%. MS calculated for C 64 H 54 N6: 907.12. Found: 907.79.

[0050]

[0051] Example 4: Synthesis of Organic Pyrrole Compound 4

[0052] (1) and (2) are the same as in Example 1.

[0053] (3) Synthesis of organic pyrrole compound 4:

[0054]

[0055] Precursor compound CN-Br (36.5 mg, 0.05 mmol), phenothiazine (29.9 mg, 0.15 mmol), copper powder (20.0 mg, 0.315 mmol), and potassium carbonate (29.0 mg, 0.21 mmol) were placed in a 25 mL double-necked flask. 5 mL of dry o-dichlorobenzene was added under a nitrogen atmosphere, and the mixture was stirred at 180 °C for 2 days. The reaction was monitored by thin-layer chromatography. The reaction was stopped after the reactants were consumed, and the reaction solution was cooled to room temperature. The o-dichlorobenzene solvent was removed by rotary evaporation. The target compound 4, or organopyrrole compound 4, was obtained by column chromatography, with petroleum ether and dichloromethane (volume ratio 2:1) as the eluent. The product was a white powder with a yield of 39%. MS calculated for C 64 H 50 N6S2:967.27.Found:967.70.

[0056] Example 5: Synthesis of organic pyrrole compound 5

[0057] (1) and (2) are the same as in Example 1.

[0058] (3) Synthesis of organic pyrrole compound 5:

[0059]

[0060] Precursor compound CN-Br (36.5 mg, 0.05 mmol), 9,10-dihydro-9,9-dimethylacridine (31.4 mg, 0.15 mmol), copper powder (20.0 mg, 0.315 mmol), and potassium carbonate (29.0 mg, 0.21 mmol) were placed in a 25 mL double-necked flask. 5 mL of dry o-dichlorobenzene was added under a nitrogen atmosphere, and the mixture was stirred at 180 °C for 2 days. The reaction was monitored by thin-layer chromatography. The reaction was stopped after the reactants were consumed, and the reaction solution was cooled to room temperature. The o-dichlorobenzene solvent was removed by rotary evaporation. The target compound 5, or organopyrrole compound 5, was obtained by column chromatography, with petroleum ether and dichloromethane (volume ratio 3:1) as the eluent. The product was a white powder with a yield of 55%.

[0061] Example 6: Test of photophysical properties of organic pyrrole compound 1.

[0062] 1 mg of organic pyrrole compound 1 and 100 mg of polystyrene (PS) or polymethyl methacrylate (PMMA) were dissolved in dichloromethane and a thin film was prepared by slow evaporation. The emission spectra of pyrrole compound 1 in toluene and the thin film were measured using an Edinburgh steady-state / transient fluorescence spectrometer FS5, and the absorption spectrum of pyrrole compound 1 in toluene was measured using a Hitachi UV-Vis spectrophotometer U-3900. Figure 1 and Figure 2 As shown, compound 1 has an emission peak at 425 nm in toluene, at 432 nm in PS film, and at 453 nm in PMMA film, classifying it as a blue light-emitting material.

[0063] Example 7: Fabrication and Characterization of OLED Devices

[0064] The fabrication steps for an OLED device with ITO / PEDOT:PSS (40nm) / EML (60nm) / TmPyPB (5nm) / TPBi (30nm) / LiF (2nm) / Al (100nm) / cathode are as follows:

[0065] (1) Use an aqueous solution of 5% Decon90 cleaning solution to sonicate for 30 minutes, then sonicate several times with deionized water, then sonicate with acetone and ethanol and dry with nitrogen gas flow; treat under ultraviolet ozone cleaner for 20 minutes to clean the ITO surface and improve the power function of the ITO electrode.

[0066] (2) A PEDOT:PSS (CLEVIOS P VP AI4083) solution was spin-coated onto an ITO substrate that had been treated with oxygen plasma to obtain a 40 nm thin film, which was then annealed in air at 150 °C for 20 minutes.

[0067] (3) Dissolve TCTA and organic pyrrole compounds (1-5) in chlorobenzene at a ratio of 90:10, and the concentration of the solution is 20 mg / mL. Spin coat this solution in a glove box to obtain a 60 nm film, and then anneal at 120 °C for 10 minutes.

[0068] (4) The annealed device was placed in a vacuum evaporation chamber, and 5nm TmPyPB, 30nm TPBi, 2nm LiF, and 100nm Al were deposited sequentially to complete the fabrication of the light-emitting device. The maximum external quantum efficiencies of the OLED devices prepared by organic pyrrole compounds 1-5 were measured to be 2.4%, 3.6%, 3.8%, 5.1%, and 4.2%, respectively. Further optimization, such as optimization of device structure, hole injection / transport layer, electron injection / transport layer, and combination optimization of host materials, will further improve the performance of the device, especially efficiency, driving voltage, and lifetime.

Claims

1. An organic azapyrrole compound, characterized by, The organic pyrrolo compound has the following structural formula:

2. A method of preparing the organic pyrrole compound according to claim 1, characterized by, The method comprises the following steps: a bromo-pyrrolo compound is coupled with a secondary aromatic amine under the catalysis of copper or a copper compound to generate an organic pyrrolo compound (I), and a synthesis route is as follows: The secondary aromatic amine is The structure of the organic azole compound (I) is shown in claim 1.

3. The organic pyrrolo compound of claim 1 is applied in an organic electronic device.

4. Use according to claim 3, characterized in that: The organic electronic device is an organic light-emitting diode, an organic photovoltaic cell, an organic light-emitting cell, an organic field effect transistor, an organic light-emitting field effect transistor, an organic laser or an organic sensor.

5. Use according to claim 3, characterized in that, The addition amount of the organic pyrrolo compound is 10%.

6. An organic electronic device, characterized in that The organic electronic device comprises the organic pyrrolo compound of claim 1.

7. Organic electronic device according to claim 6, characterized in that The addition amount of the organic pyrrolo compound is 10%.

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