An aie-type luminescent material and a preparation method thereof

Abstract

The application selects [Ir(OMe)cod]2, tris(pentafluorophenyl)phosphine as a catalyst, dissolves pinacol borate in 1,4-dioxane, and reacts with various perylene imide cores to prepare borate-p-quinone site imide derivatives with four active sites, then links the borate-p-quinone site imide derivatives through a one-step palladium catalytic coupling reaction to prepare a series of optoelectronic materials with high symmetry and intramolecular twist. Through the determination of the fluorescent properties of the material, it can be known that the material prepared by the application has the advantages of red light emission wavelength, high fluorescent quantum yield and the like. The n-type PDI optoelectronic material developed by the application has a relatively simple synthesis method, and the reaction condition is not harsh, thereby providing a new way for the development of n-type optoelectronic materials.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic light-emitting materials, and particularly relates to an AIE type light-emitting material and a preparation method thereof. BACKGROUND

[0002] Perylene imides and their derivatives (PDI) have been widely used as an excellent n-type optoelectronic material in organic field effect transistors (OFETs), OPVs, organic redox flow batteries, organic photodetectors, and many other applications. PDI plays a prominent role in important processes such as charge transport, energy transport, singlet fission, and photoinduced electron transfer in the core of these organic materials. For many applications of PDI, it is beneficial to have the core of PDI away from planarity. For example, a nonplanar, twisted core greatly improves the performance of solar cell devices and provides a rich design theme for nonfullerene electron acceptors in optoelectronic devices. The present application describes a new twisted structure of PDI, which reduces the energy of the HOMO-LUMO transition, and the curved PDI core reduces the energy of the LUMO. This mode of molecular twisting provides a previously unexplored singlet and triplet energy PDI.

[0003] The present application introduces the triphenylamine and its derivative groups modified by carbazole, thiophene, etc. into the four bent structures of PDI, which not only effectively improves the twist of the molecule in the molecular structure, but also has a strong improvement on the molar extinction coefficient, fluorescence quantum efficiency, etc. of the material. Through the study of the influence of the structure and energy level of the donor and acceptor on the fluorescence performance of the material, the design idea of the n-type optoelectronic material is expanded, which has important significance for the development of higher performance optoelectronic materials. Based on this, the present application provides an AIE type light-emitting material and a preparation method thereof. SUMMARY

[0004] The purpose of the present application is to provide an AIE type light-emitting material, and a novel n-type intramolecular twisted PDI molecule is constructed, and the prepared fluorescent material has good fluorescence light stability and high fluorescence quantum yield.

[0005] An AIE type light-emitting material has the following structural formula:

[0006]

[0007] Among them,

[0008] R1 is selected from one or two of , , ,

[0009] R2 is selected from , ​, , one or more of the following:

[0010] A preparation method of an AIE type light-emitting material, steps comprising: using [Ir(OMe)cod]2 and tris(pentafluorophenyl)phosphine as a catalyst to dissolve pinacol borate in 1,4-dioxane and perform a first step reaction with a perylene imide nucleus to prepare a borate- perylene imide derivative with four active sites of ortho carbonyl sites, and then linking the borate- perylene imide derivative with a triphenylamine derivative through a one-step palladium catalytic coupling reaction to obtain the red light organic light-emitting material.

[0011] Further, the first step reaction is to slowly warm to 100-120 DEG C and keep for 60-80 h.

[0012] Further, the catalyst in the coupling reaction is tetrakis(triphenylphosphine)palladium.

[0013] Further, the coupling reaction needs to be carried out under oxygen-free DMSO conditions.

[0014] Further, the coupling reaction condition is 80-100 DEG C for 60-80 h.

[0015] Further, the triphenylamine derivative includes a thiophene triphenylamine derivative and / or a carbazole triphenylamine derivative.

[0016] The beneficial effects of the present application are:

[0017] The present application is based on a conventional perylene imide nucleus as a light-emitting main body, and by introducing a reaction site on the four carbons adjacent to the carbonyl group, a highly symmetrical n-type light-emitting nucleus is constructed, which is different from the related PDI optoelectronic materials in the prior art. At present, most of such materials are based on 1,7 modification, while the present application breaks through the conventional molecular design and first introduces carbazole triphenylamine and its derivatives at the four highly symmetrical positions adjacent to the carbonyl group. A new type of PDI optoelectronic material with intramolecular twist structure is constructed with carbazole triphenylamine derivative as the energy donor, perylene imide nucleus group as the energy acceptor. By changing the energy level of the energy acceptor to adjust the donor-acceptor energy level difference, the structural relationship between the structure and the fluorescence performance is studied, and high-efficiency n-type PDI optoelectronic material is developed.

[0018] The application provides a highly symmetrical n-type PDI photoelectric material and a synthesis method thereof, which mainly realizes the activation of four carbonyl ortho carbon atoms, introduces pinacol borate or bromine at the position, and then introduces triphenylamine carbazole, thiophene and other derivatives into the main PDI light-emitting core through a palladium-catalyzed coupling reaction, so as to construct an n-type PDI photoelectric material with an intramolecular energy donor-acceptor structure. Meanwhile, the introduction of a large group causes a large internal planar torsion of the molecule, so that the original intention of material design is realized. The synthesis of the photoelectric material mainly includes the preparation of a carbazole triphenylamine precursor, the preparation of a multi-site active PDI core, and the preparation of a target material through a palladium-catalyzed coupling reaction. The material structure is novel, and the synthesis method is relatively simple. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0020] Figure 1 The infrared spectrum of the probe molecule BSA-OJ.

[0021] Figure 2 The ultraviolet absorption spectrum of the probe molecule BSA-OJ in dichloromethane solution.

[0022] Figure 3 The fluorescence emission spectrum of the probe molecule BSA-OJ in dichloromethane solution. EMBODIMENT

[0023] The technical solutions of the present application will be described below in conjunction with the drawings. Obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0024] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other. EMBODIMENT

[0025] Step 1: Preparation of active PDI core at carbonyl ortho position

[0026]

[0027] Compound PDI-2 (3 g, 11 mmol), [lr(OMe)cod]2 (0.12 g, 0.2 mmol), tris(pentafluorophenyl)phosphine (0.4 g, 0.8 mmol), pinacolboronate (12 g, 48 mmol) were dissolved in 100 mL of 1,4-dioxane under nitrogen protection, then slowly warmed to 110 o C for 72 h, the reaction progress was tracked by HPLC, after the reaction was completed, the solvent in the reaction mixture was removed by rotary evaporator, the residue was quickly filtered by silica gel plug with dichloromethane as eluent, then the solvent was removed again, PDI-B2 4.0 g was obtained by recrystallization in dichloromethane / MeOH, yield: 65 %.

[0028] 1 H NMR (300 MHz, CDCl3): δ 1 H NMR (300 MHz, CDCl3): δ 8.52 (s, 4H),5.04-4.76 (m, 2H), 2.32-2.06 (m, 4H), 1.42-1.32 (m, 4H), 1.24-1.28 (m, 12H),1.2(s, 48H), 0.94 (t, J = 7.5 Hz, 12H).

[0029] Step 2: Construction of the molecule

[0030]

[0031] Compound PDI-B2 (3.0 g, 2.7 mmol), 4-bromotriphenylamine (3.9 g, 12 mmol), tetrakis(triphenylphosphine)palladium (0.4 g, 0.35 mmol) and potassium carbonate (1.6 g, 12 mmol) were dissolved in DMSO (100 mL) under nitrogen protection, the system was vacuumed for 15 minutes, replaced with nitrogen for 10 minutes, and the cycle was repeated three times, then the system was warmed to 90 °C for 72 h. After the reaction was completed, the reaction mixture was cooled to room temperature, poured into ice water (100 mL), the pH was adjusted to acidic, filtered and dried, column chromatography gave PDI-SA 5.2 g as a dark red solid, yield: 67 %.

[0032] 1H NMR (300 MHz, CDCl3): δ 8.52 (s, 4H), 7.50-7.24(m, 16H), 7.20-7.14(m, 16H), 7.08-7.20(m, 24H), 5.02-4.76 (m, 2H), 2.32-2.06 (m, 4H), 1.42-1.32(m, 4H), 0.94 (t, J = 7.5 Hz, 12H).. Example

[0033] The synthetic method in Example 2 is similar to that in Example 1, and the preparation of bromothiophene triphenylamine derivative is added in Example 2: the main method is to use 2-thiophene boronic acid and tribromoaniline as raw materials, tetrakis(triphenylphosphine)palladium as catalyst, and react under alkaline conditions at 85 ℃ for 24 h to prepare thiophene-modified tribromo triphenylamine.

[0034] Step 1: Preparation of bromothiophene triphenylamine derivative

[0035]

[0036] Under nitrogen protection, a mixture of compound SF-1 (4.0 g, 8.2 mmol), 2-thiophene boronic acid (2.6 g, 20 mmol), tetrakis(triphenylphosphine)palladium (0.2 g, 0.17 mmol) and potassium carbonate (3.3 g, 24 mmol) was dissolved in DMSO (100 mL), the system was vacuumed for 10 minutes, replaced with nitrogen for 10 minutes, and the cycle was repeated three times, and then the system was heated to 85 ℃ for 24 h. After the reaction was completed, the reaction mixture was cooled to room temperature, poured into ice water (100 mL), filtered and dried, and column chromatography gave dark yellow solid SF-2 2.4 g, yield: 62%.

[0037] 1 H NMR (300 MHz, CDCl3): δ 7.72-7.70 (m, 2H),7.40-7.38(m, 8H), 7.13-6.99(m, 8H)。

[0038] Step 2: Preparation of active PDI core with carbonyl ortho position

[0039]

[0040] PDI-B3 was prepared in reference example 1 step 2, yield: 70 %.

[0041] 1H NMR (CDC13, ppm): δ 8.52 (s, 4H), 5.04-4.76 (m, 2H), 2.32-2.06 (m,8H), 2.02-1.82 (m, 8H), 1.35-1.30 (m, 8H), 1.2(s, 48H), 0.94 (t, J = 7.5 Hz,12H)..

[0042] Step 3: Construction of the molecule

[0043]

[0044] Compound PDI-B3 (3.0 g, 2.6 mmol), 4-bromo triphenylamine (7.6 g, 16 mmol), tetrakis triphenylphosphine palladium (0.4 g, 0.35 mmol) and potassium carbonate (2.2 g, 16 mmol) were dissolved in DMSO (100 mL) under nitrogen protection, the system was vacuumed for 15 minutes, replaced with nitrogen for 10 minutes, and the cycle was repeated three times, then the system was heated to 90 °C for 72 h. After the reaction was completed, the reaction mixture was cooled to room temperature, poured into ice water (100 mL), adjusted to pH acidic, filtered and dried, and column chromatography gave a dark red solid PDI-SF 3.5 g, yield: 60%. δ 8.50 (s, 4H), 7.72-7.70 (m, 8H), 7.50-7.24 (m, 16H) 7.40-7.38 (m, 32H),, 7.20-7.14 (m, 16H), 5.02-4.76 (m, 2H), 2.32-2.06 (m, 8H), 1.42-1.32 (m, 8H), 1.35-1.30 (m, 8H), 0.94 (t, J = 7.5 Hz, 12H). Example

[0045] The synthesis of Example 3 was similar to Example 1, except that the brominated triphenylamine derivative used in Example 3 was commercially available.

[0046]

[0047] PDI-OJ was prepared in Step 3 of Reference Example 2 as a green solid with a yield of 56 %.

[0048] 1H NMR (CDC13, ppm): δ 8.52 (s, 4H), 7.37-7.55 (m, 16H), 7.18-6.78 (m, 32H), 5.02-4.76 (m, 2H), 3.82 (s, 24H), 1.35-1.30 (m, 4H),, 1.42-1.32 (m, 4H), 1.24-1.28 (m, 12H), 0.94 (t, J = 7.5 Hz, 12H). Example

[0049] The synthesis of Example 4 was similar to Example 1 except that the bromo-pyridine triphenylamine derivative needed to be prepared. This was done by dissolving the pyridine-modified triphenylamine derivative in dry THF and slowly adding a solution of NBS in DMF dropwise at room temperature. The reaction was stirred at room temperature overnight to give the product.

[0050] Step 1: Preparation of bromo-pyridine triphenylamine derivative

[0051]

[0052] Compound BD-1 (6.0 g, 15 mmol) was dissolved in dry THF and a solution of NBS (0.9 g, 15 mmol) in DMF was added slowly dropwise at room temperature. The reaction was stirred at room temperature overnight to give a light yellow solid 6.8 g, yield: 95 %.

[0053] 1 H NMR (CDC13, ppm): δ 8.62-8.60 (d, J = 6 Hz, 4H), 8.02-8.00 (d, J = 6 Hz, 4H), 7.55-7.37 (m, 8H), 7.07-7.09 (m, 4H).

[0054] Step 2: Assembly of the molecule

[0055]

[0056] BSA-BD was prepared as a green solid in 65 % yield according to the procedure described in Reference Example 2, Step 3.

[0057] 1H NMR (CDCl3, ppm): δ 8.62-8.60(d, J=6Hz, 8H), 8.56 (s, 4H), 8.02-8.00(d, J=6Hz, 8H), 7.37-7.55(m, 16H), 7.18-6.78(m, 32H), 5.02-4.76 (m, 2H),1.35-1.30 (m, 8H), 0.94 (t, J = 7.5 Hz, 12H)。

[0058] The materials prepared in Examples 1-4 were subjected to fluorescence and ultraviolet spectrum tests: the materials were prepared into thin laminated sheets, and the ultraviolet absorption spectrometer and fluorescence spectrometer were used to determine the absorption spectrum and emission spectrum of the materials respectively, and the fluorescence quantum yield was calculated, and the spectral data of the corresponding molecules are shown in Table 1 below.

[0059] Table 1 Fluorescence spectral properties of dyes in dichloromethane solution

[0060] Compound Maximum absorption λ 波长 nm ]]> Maximum emission λ 波长 nm ]]> Fluorescence quantum efficiency % Solid fluorescence quantum efficiency % Example 1 BSA-SA 584 695 60 30% Example 2 BSA-SF 585 688 75 42% Example 3 BSA-OJ 588 692 68 35% Example 4 BSA-BD 582 690 72 40%

[0061] From the data in Table 1, it can be seen that the comprehensive performance of Example 2 is the best. The reaction conditions designed by the present application are mild, the reaction is efficient, the operation is simple, the applicability is wide, and the present application provides a new idea for enriching and developing AIE optoelectronic materials.

[0062] Finally, it should be noted that the above examples are only used to illustrate the present application and not to limit the technical solutions described in the present application; those skilled in the art should understand that the present application can still be modified or replaced equivalently; and all technical solutions and improvements that do not deviate from the spirit and scope of the present application should be covered in the scope of the claims of the present application.

Claims

1. An AIE-type luminescent material, characterized in that, The structural formula is one or more of the following: 、 、 、 。 2. The method of claim 1, wherein the step of The application relates to a red light-emitting material and a preparation method thereof. The first step reaction is slowly heated to 100-120 DEG C and kept for 60-80 h.

3. The method for preparing an AIE-type luminescent material according to claim 2, characterized in that, The coupling reaction needs to be carried out under the condition of oxygen-free DMSO.

4. The method for preparing an AIE-type luminescent material according to claim 2, characterized in that, The coupling reaction condition is 80-100 DEG C for 60-80 h.

5. The method for preparing an AIE-type luminescent material according to claim 2, characterized in that, ​ 6. The method for preparing an AIE-type luminescent material according to claim 2, characterized in that, ​

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