A pure organic luminophore with aggregation-induced electrochemiluminescence assembled from terpyridine fragments and a synthesis method thereof

Abstract

The application discloses a kind of pure organic luminophore with aggregation-induced electrochemiluminescence assembled by terpyridine fragment and synthesis method thereof, chemical structural formula is: The pure organic luminophore I and II one is synthesized by terpyridine fragment assembled pure organic luminophore using dialdehyde substituent compound, 2-acetylpyridine and ammonia water under the action of potassium tert-butoxide.The pure organic luminophore I and II another is synthesized by terpyridine fragment assembled pure organic luminophore using boronic acid or boron ester substituent compound and halogen substituent compound under the action of palladium catalyst, inorganic base.The pure organic luminophore III is synthesized by terpyridine fragment assembled pure organic luminophore using peroxide oxidation pure organic luminophore I.The pure organic luminophore of the application has strong aggregation-induced electrochemiluminescence, can be applied to sensor, organic light emitting semiconductor and other fields, and has wide application prospect.

Description

Technical Field

[0001] The present invention relates to the field of aggregation-induced electrochemiluminescence, and in particular to a pure organic luminescent body with aggregation-induced electrochemiluminescence assembled from terpyridine fragments and a synthesis method thereof. Background Art

[0002] 2,2':6',2"-terpyridine (also known as terpyridine) and its derivatives are a widely studied class of ligands in coordination chemistry. Due to their unique electrochemical and photophysical properties, they have been widely used in various optoelectronic fields, including photochemical nanodevices, luminescent sensors, cancer cell therapy, and molecular catalysis. The concept of aggregation-induced electrochemiluminescence (AIECL) has attracted widespread attention since it was first proposed by Cola et al. in 2017. However, research on organic materials with AIECL is still in its infancy. Therefore, the development of pure organic luminescent materials assembled from terpyridine fragments with AIECL properties is of great significance. The structural formula of terpyridine is as follows:

[0003] Summary of the Invention

[0004] To this end, the present invention provides a pure organic luminescent body with aggregation-induced electrochemiluminescence assembled from terpyridine fragments.

[0005] In the first aspect of the present invention, there are provided pure organic luminophores I, II and III assembled from terpyridine fragments and having aggregation-induced electrochemiluminescence, the chemical structures of which are as follows:

[0006] ;

[0007] in,

[0008] n is an integer from 1 to 20;

[0009] R 1 、R 2 、R 3 and R 4 Each is independently hydrogen, fluorine, chlorine, bromine, iodine, cyano, nitro, aldehyde, C6-C 18 Aryloxycarbonyl, C6-C 18 Arylthiocarbonyl, C6-C 18 Arylaminocarbonyl, C6-C 18 Aryl, C6-C 18 Arylsulfonyl, C6-C 18 Arylaminosulfonyl, C6-C 18 Heterocyclic aryloxycarbonyl, C6-C 18 Heterocyclic arylthiocarbonyl, C6-C18 heteroaromatic aminocarbonyl, C6-C 18 heteroaromatic, C6-C 18 heteroaromatic sulfonyl or C6-C 18 heteroaromatic aminosulfonyl;

[0010] The pure organic luminophore I does not include n = 1 and 3, R 1 , R 2 , R 3 and R 4 each independently is hydrogen.

[0011] In a second aspect of the present application, a method for preparing the pure organic luminophores I and II as described in the present application is provided, which comprises: synthesizing the pure organic luminophores I and II by the following condensation reaction:

[0012]

[0013]

[0014] The starting material 1 or 2, respectively, is subjected to condensation reaction with reagent 2-acetylpyridine and ammonia water to generate the pure organic luminophore I or II, respectively;

[0015] The condensation reaction is carried out in an organic solvent under the action of an organic strong base.

[0016] In a third aspect of the present application, another method for preparing the pure organic luminophores I and II as described in the present application is provided, which comprises: synthesizing the pure organic luminophores I and II by the following coupling reaction:

[0017]

[0018]

[0019] The starting material 3 is subjected to coupling reaction with reagent 4 or 5, respectively, to generate the pure organic luminophore I or II, respectively; wherein L1 is fluorine, chlorine, bromine or iodine, and L2 is boronic acid or boron ester; or L1 is boronic acid or boron ester, and L2 is fluorine, chlorine, bromine or iodine;

[0020] The coupling reaction is carried out in an organic solvent and water under the action of a palladium catalyst and an inorganic base under inert conditions; the temperature of the coupling reaction is 80-160°C.

[0021] In a fourth aspect of the present application, a method for preparing the pure organic luminophore III as described in the present application is provided, which comprises: synthesizing the pure organic luminophore III by the following oxidation reaction:

[0022]

[0023] Pure organic luminescent body I is oxidized with a peroxide reagent to generate pure organic luminescent body III;

[0024] The oxidation reaction is carried out in an organic solvent.

[0025] Compared with the prior art, the beneficial technical effects of the present invention are:

[0026] The present invention designed and synthesized a pure organic luminescent body assembled from terpyridine fragments, and successfully used it in the field of aggregation-induced electrochemiluminescence, all of which showed strong aggregation-induced electrochemiluminescence signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 : Electrochemiluminescence intensity diagram of 1,4-bis(2,2',6',2''-terpyridin-4'-yl)-2,5-difluorobenzene (i.e., pure organic light-emitting compound Ia), 2,5-bis(2,2',6',2''-terpyridin-4'-yl)pyridine (i.e., pure organic light-emitting compound IIa) and 1,4-bis(1,1',1''-trioxo-2,2',6',2''-terpyridin-4'-yl)benzene (i.e., pure organic light-emitting compound IIIa) in the aggregated state. DETAILED DESCRIPTION

[0028] Unless otherwise specified, the reagents involved in the following examples are commercial products and are of chemical grade purity. In order to more clearly explain the technical problems and technical solutions solved by the present invention, the specific examples described below further illustrate the present invention in detail. The specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0029] Example 1

[0030] Preparation of pure organic luminescent material Ia

[0031]

[0032] To a 25 mL round-bottom flask were added 0.0425 g of 2,5-difluoroterephthalaldehyde, 0.224 mL of 2-acetylpyridine, 0.1625 g of potassium tert-butoxide, 1.75 mL of aqueous ammonia solution, and 2.5 mL of anhydrous ethanol. The reaction was stirred at room temperature for 24 hours. The solid was collected by filtration, washed three times with water, recrystallized from chloroform and ethanol, and dried to obtain 0.0403 g of a white solid (i.e., pure organic light-emitting compound Ia) with a yield of 28%.

[0033] HRMS (ESI) m / z calcd for C 36 H 22 F2N6 ([M+H] +): 577.1947; found: 577.1947.

[0034] Example 2

[0035] Preparation of pure organic luminescent material Ia

[0036]

[0037] To a 50 mL Schlenk flask were added 0.0504 g of 2,5-difluoroterephthaloboric acid, 0.0312 g of 4-bromo-2,2',6',2''-terpyridine, 0.083 g of K2CO3, 0.012 g of Pd(PPh3)4, 10 mL of tetrahydrofuran, and 1 mL of water. Under nitrogen protection, the reaction was stirred at 95°C for 24 hours. The temperature was cooled to room temperature and the solvent was removed by concentration. Chloroform was added to the residue, which was heated to dissolve and filtered. The filtrate was concentrated to remove the solvent and recrystallized from chloroform and methanol. The reaction was dried to obtain 0.0202 g of a white solid (i.e., pure organic light-emitting compound Ia) with a yield of 35%.

[0038] HRMS (ESI) m / z calcd for C 36 H 22 F2N6 ([M+H] + ): 577.1947; found: 577.1947.

[0039] Example 3

[0040] Preparation of pure organic luminescent material IIa

[0041]

[0042] In a 25 mL round-bottom flask, 0.027 g of 2,5-dialdehyde pyridine, 0.180 mL of 2-acetyl pyridine, 0.130 g of potassium tert-butoxide, 1.4 mL of aqueous ammonia solution, and 2.0 mL of anhydrous ethanol were added. The reaction was stirred at room temperature for 24 hours. The solid was collected by filtration, washed three times with water, recrystallized from chloroform / methanol, and dried to obtain 0.118 g of a yellow solid (i.e., pure organic light-emitting compound IIa) with a yield of 64%.

[0043] HRMS (ESI) m / z calcd for C 35 H 23 N7 ([M+H] + ): 542.2088; found: 542.2084.

[0044] Example 4

[0045] Preparation of pure organic luminescent material IIa

[0046]

[0047] To a 50 mL Schlenk tube were added 0.071 g of 1,4-dibromopyridine, 0.269 g of 4-pinacol borate-2,2',6',2''-terpyridine, 0.248 g of K2CO3, 0.035 g of Pd(PPh3)4, 12 mL of THF, and 1.2 mL of water. Under nitrogen protection, the reaction was stirred at 85°C for 48 hours. The temperature was then lowered to room temperature, the catalyst was removed by filtration, and the solvent was concentrated to obtain a white solid. The solid was recrystallized from chloroform / methanol and dried to obtain 99 mg of a white powder (i.e., pure organic light emitter IIa) with a yield of 61%.

[0048] HRMS (ESI) m / z calcd for C 35 H 23 N7 ([M+H] + ): 542.2088; found: 542.2084.

[0049] Example 5

[0050] Preparation of pure organic light-emitting compound IIIa

[0051]

[0052] To a 50 mL round-bottom flask filled with 15 mL of chloroform, add 0.27 g of 1,4-bis(2,2',6',2''-terpyridin-4'-yl)benzene and stir in an ice-water bath. Then, continuously add 0.604 g of 3-chloroperoxybenzoic acid. Stirring is continued for 30 minutes while cooling in an ice-water bath, after which the ice-water bath is removed. The reaction mixture is allowed to react at room temperature for 53 hours, filtered, and the solid washed with ethanol and ethyl acetate and dried under vacuum to yield 0.087 g of a white solid (pure organic light-emitting compound IIIa) in a 27% yield.

[0053] HRMS (ESI) m / z calcd for C 36 H 24 N6O6 ([M+H] + ): 637.1831; found: 637.1828.

[0054] Example 6

[0055] A bare glassy carbon electrode (GCE) was polished with 1.0 μm and 0.3 μm alumina powders, then rinsed with distilled water and dried at room temperature. Subsequently, 10 μL of a 5 mM solution of pure organic luminophore Ia, IIa, or IIIa was dropped onto the GCE and allowed to dry naturally in the dark, yielding a modified GCE electrode.

[0056] 3 mL of 0.2 M PBS (pH 8.0) solution containing 0.1 M potassium chloride and 20 mM tri-n-propylamine was used as the electrolyte. Then, on an electrochemiluminescence (ECL) analysis system, the modified GCE electrode was used as the working electrode, the Ag / AgCl (containing saturated KCl solution) electrode was used as the reference electrode, and the platinum wire electrode was used as the counter electrode. The voltage was set to 1.1–1.7 V, and the scan rate was set to 0.1 V s. -1 , the photomultiplier tube high voltage is 750 V, the amplification level is 4, and electrochemiluminescence measurement is performed. Pure organic luminophores Ia, IIa or IIIa all show strong aggregation-induced electrochemiluminescence, such as Figure 1 shown.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any changes, equivalent replacements and improvements made within the principles and spirit of the present invention are included in the scope of protection of the present invention.

Claims

1. A pure organic light emitting body assembled from terpyridine fragments, characterized in that: The chemical structure of the pure organic light-emitting body is as follows: ； in, n is 1; R 1 、R 2 、R 3 and R 4 are each independently hydrogen, fluorine, chlorine, bromine, or iodine; The pure organic light emitting body I does not include n = 1, R 1 、R 2 、R 3 and R 4 For hydrogen.

2. The method for synthesizing a pure organic light emitting body according to claim 1, characterized in that , the method of pure organic light-emitting bodies I and II, the method comprising: synthesizing pure organic light-emitting bodies I and II by the following condensation reaction: ； ； Raw material 1 or 2 is used to generate pure organic luminescent material I or II through condensation reaction with reagent 2-acetylpyridine and ammonia water; The condensation reaction is carried out in an organic solvent under the action of a strong organic base.

3. The method for synthesizing a pure organic light emitting body according to claim 1, characterized in that , the method of pure organic luminescent bodies I and II, the method comprising: synthesizing pure organic luminescent bodies I and II by the following coupling reaction: ； ； Raw material 3 is coupled with reagent 4 or 5 to generate pure organic light-emitting body I or II, respectively; wherein L1 is fluorine, chlorine, bromine or iodine, and L2 is boric acid or boron ester; or L1 is boric acid or boron ester, and L2 is fluorine, chlorine, bromine or iodine; The coupling reaction is carried out in an organic solvent and water under inert conditions with the action of a palladium catalyst and an inorganic base; the coupling reaction temperature is 80-160°C.

4. The method for synthesizing a pure organic light emitting body according to claim 1, characterized in that , the method of the pure organic light emitting body III, the method comprising: synthesizing the pure organic light emitting body III by the following oxidation reaction: ； Pure organic luminescent body I is oxidized with a peroxide reagent to generate pure organic luminescent body III; The oxidation reaction is carried out in an organic solvent.

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