阅读说明：本技术 具有aie效应的二氰基亚甲基-4h-吡喃分子、构建方法及应用 (dicyanomethylene-4H-pyran molecule with AIE effect, construction method and application ) 是由 刘培念 李登远 王恒 李世文 王婕 于 2021-08-04 设计创作，主要内容包括：本发明提供了基于DM的具有AIE效应的荧光团F1-F5以及Cu～(2+)荧光探针FP1,基于二氰基亚甲基-4H-吡喃(DM)的衍生物常表现为荧光淬灭效应,本发明通过对其官能团化,公开了五种具有聚集诱导发光(AIE)性质的荧光团(F1-F5),及以F1为基础的铜离子荧光探针(FP1)的制备方法和应用。本发明将作为识别基团的三联吡啶与F1偶联生成了荧光探针FP1。在含水量为90％的THF-H-(2)O的混合溶液中,探针FP1表现出较强的荧光发射,加入含有Cu～(2+)的水溶液时,三联吡啶与之络合,导致荧光淬灭。该探针在水溶液中Cu～(2+)的检测方面具有一定的应用价值。(The present invention provides DM-based fluorophores F1-F5 with AIE effect and Cu 2+ The invention discloses a fluorescent probe FP1, a derivative based on dicyanomethylene-4H-pyran (DM) usually shows a fluorescence quenching effect, five fluorophores (F1-F5) with aggregation-induced emission (AIE) properties by functionalizing the fluorescent probe FP1, and a preparation method and application of a copper ion fluorescent probe (FP1) based on F1. In the invention, a terpyridine serving as a recognition group is coupled with F1 to generate a fluorescent probe FP 1. THF-H at a water content of 90% 2 In the mixed solution of O, the probe FP1 shows stronger fluorescence emission, and Cu is added 2+ In the case of aqueous solution of (A), terpyridine is complexed with the terpyridineAnd combined, resulting in fluorescence quenching. The probe is Cu in an aqueous solution 2+ The detection aspect of (2) has certain application value.)

1. DM-based fluorophore F1-F5 with AIE Effect, and Cu²⁺Fluorescent probe FP1, characterized by: the structural formulas of the DM, the F1-F5 and the FP1 are shown as the following formula 1:

2. the DM-based fluorophore of claim 1 having AIE effect F1-F5, and Cu²⁺The preparation method of the fluorescent probe FP1 is characterized by comprising the following steps:

a) dissolving DM, p- (trimethylsilylethynyl) benzaldehyde and sodium methoxide in absolute methanol under the condition of argon;

b) heating the obtained solution to 70-85 ℃, and reacting for 3-12 h;

c) pouring the reaction liquid into ice water after the reaction is finished, adding dilute hydrochloric acid until the pH of the solution is 4, extracting and combining the solution for multiple times by using DCM, drying the solution, distilling the solution under reduced pressure to obtain a solid, and separating the solid by column chromatography to obtain F1;

d) repeating the steps a) b) c), respectively replacing p- (trimethylsilylethynyl) benzaldehyde with p-vinylbenzaldehyde and benzaldehyde, respectively, to obtain F2 and F3;

e) in Ar gas environment, adding o-iodobenzyl alcohol, PdCl₂(PPh₃)₂Dissolving CuI in redistilled triethylamine and redistilled tetrahydrofuran, adding F1 after a few minutes, stirring at room temperature, and monitoring the reaction process by TLC;

f) after the reaction is completed, adding proper amount of saturated NH₄Quenching the reaction by using a Cl solution, extracting and combining the solution for multiple times by using DCM, drying the solution, removing the solvent by reduced pressure distillation, and carrying out column chromatography separation to obtain F4;

g) repeating the steps e) and F), and replacing o-iodobenzyl alcohol with o-methoxy methyl iodobenzene to prepare F5;

h) dissolving p-iodobenzaldehyde and 2-acetylpyridine in ethanol, and stirring until the solid is completely dissolved;

i) adding strong base and ammonia water into the mixed solution obtained in the step h), stirring and refluxing for 24h, cooling to room temperature after complete reaction, performing suction filtration to obtain a solid, and then using anhydrous Et₂O washing for several times to obtain an intermediate product I-Py shown in the following formula 2:

j) under the condition of argon, the intermediate I-Py and PdCl obtained in the step I)₂(PPh₃)₂Dissolving CuI in triethylamine, adding F1 after a few minutes, and reacting at room temperature; after the reaction is completed, adding proper amount of saturated NH₄And (3) quenching the reaction by using a Cl solution, adding DCM for multiple times of extraction, removing the solvent by reduced pressure distillation, and carrying out column chromatography separation by using aluminum trioxide to obtain an orange solid, namely FP 1.

3. The method of claim 2, wherein: the molar ratio of the DM, the p- (trimethylsilylethynyl) benzaldehyde and the sodium methoxide in the step a) is 1: 1.2: 6; the solution heating temperature is 70 ℃, and the reaction time is 3 h.

4. The method of claim 2, wherein: in the steps c) and f), DCM is added for extraction for three times, and after products are combined, anhydrous Na is added₂SO₄And (5) drying.

5. The method of claim 2, wherein: step e) F1, o-iodobenzyl alcohol, PdCl₂(PPh₃)₂The molar ratio of CuI is 1:1.3:0.04: 0.04;

the molar ratio of the p-iodobenzaldehyde to the 2-acetylpyridine in the step h) is 1: 2.

6. The method of claim 2, wherein: the strong base used in the step i) is potassium hydroxide, and the molar weight of the potassium hydroxide is 1.2 times of that of the p-iodobenzaldehyde; the ammonia water has a concentration of 25% and the same amount as ethanol, and is slowly added into the solution in small amount for multiple times.

7. The method of claim 2, wherein: the molar ratio of the intermediate I-Py to the F1 in the step j) is 1:1.1, and PdCl is used₂(PPh₃)₂And CuI were both 1% mmol.

8. The method of claim 2, wherein: the column chromatography eluting agent in the step c) is dichloromethane and petroleum ether with the volume ratio of 1: 1; the column chromatography eluting agent used in the step f) is dichloromethane and petroleum ether, and the volume ratio is 2: 1; the column chromatography eluent used in the step j) is dichloromethane and methanol, and the volume ratio is 100: 1.

9. Use of the fluorophore F1-F5 according to claim 1 in the preparation of a detection reagent based on the AIE effect.

10. Preparation of Cu with fluorescent probe FP1 according to claim 1²⁺The application of the detection reagent.

Technical Field

The invention belongs to the technical field of organic synthesis, and particularly relates to five compounds with AIE effect, a synthesis method and a fluorescent probe for detecting metal ions. In particular to the construction of a fluorescent skeleton (F1-F5) based on DM and the construction and application of a fluorescent probe (FP1) taking terpyridine as a recognition group.

Background

Cu²⁺Can be used as a component of partial enzyme or as a catalyst to participate in enzymatic biochemical reaction, plays an important role in a plurality of physiological processes, and is one of trace elements necessary for life activities. The long-term copper deficiency can affect the normal work of the body, especially the neutrophil and macrophage, and further can cause the patient to suffer from leukemia; and excessive Cu²⁺The toxicity is greatly enriched in vivo, and the senile dementia and other nervous system diseases can be caused.

The copper pollution sources mainly include the exploitation, subsequent processing and the like of copper-zinc ores. The production waste continues to contaminate the soil and water systems under the action of weathering, acidification and rainfall. Cu²⁺Is a common pollutant affecting fishery development, and the toxicity threatens the survival of many aquatic organisms. Irrigating farmlands with copper-containing wastewater can cause copper to accumulate in soil and crops and finally enter human food circulation, thereby bringing threat to human health.

Cu²⁺Conventional detection includes atomic absorption (emission) spectroscopy, capillary electrophoresis, and the like. However, these broad-spectrum detection methods usually require expensive and heavy instruments, are not suitable for on-site detection and on-line tracking and monitoring, generally require long time for separation detection, and have low flexibility and cost performance. Therefore, a rapid, simple and reliable Cu is designed and developed²⁺Detection methods are imperative.

The derivatives of dicyanomethylene-4H-pyran (DM) are susceptible to intramolecular ultra-fast charge transfer (ICT) processes due to their typical donor-pi-acceptor (D-pi-a) structure. But the application is limited due to the strong surface accumulation which is often shown as the quenching effect of the aggregated fluorescence. If it can be functionalized, it may be possible to reduce the stacking effect and to achieve aggregation-induced emission (AIE).

Disclosure of Invention

The present invention was made in view of the above problems, and provides DM-based fluorophores F1-F5 having AIE effect and Cu²⁺Fluorescent probe FP1, and its preparation method and application.

In order to achieve the purpose, the invention adopts the following technical scheme:

in a first aspect of the invention, there is provided a DM-based fluorophore having an AIE effect F1-F5, and Cu²⁺The fluorescent probe FP1 has the structural formula shown in formula 1, wherein DM, F1-F5 and FP1 are as follows:

in a second aspect of the invention, a preparation method of the above F1-F5 and FP1 is provided, which comprises the following steps:

a) dissolving DM, p- (trimethylsilylethynyl) benzaldehyde and sodium methoxide in absolute methanol under the condition of argon;

b) heating the obtained solution to 70-85 ℃, and reacting for 3-12 h;

c) pouring the reaction liquid into ice water after the reaction is finished, adding dilute hydrochloric acid until the pH of the solution is 4, extracting and combining the solution for multiple times by using DCM, drying the solution, distilling the solution under reduced pressure to obtain a solid, and separating the solid by column chromatography to obtain F1;

d) repeating the steps a) b) c), respectively replacing p- (trimethylsilylethynyl) benzaldehyde with p-vinylbenzaldehyde and benzaldehyde, respectively, to obtain F2 and F3;

e) in Ar gas environment, adding o-iodobenzyl alcohol, PdCl₂(PPh₃)₂Dissolving CuI in redistilled triethylamine and redistilled tetrahydrofuran, adding F1 after a few minutes, stirring at room temperature, and monitoring the reaction process by TLC;

f) after the reaction is completed, adding proper amount of saturated NH₄Quenching the reaction by using a Cl solution, extracting and combining the solution for multiple times by using DCM, drying the solution, removing the solvent by reduced pressure distillation, and carrying out column chromatography separation to obtain F4;

g) repeating the steps e) and F), and replacing o-iodobenzyl alcohol with o-methoxy methyl iodobenzene to prepare F5;

h) dissolving p-iodobenzaldehyde and 2-acetylpyridine in ethanol, and stirring until the solid is completely dissolved;

i) adding strong base and ammonia water into the mixed solution obtained in the step h), stirring and refluxing for 24h, cooling to room temperature after complete reaction, performing suction filtration to obtain a solid, and then using anhydrous Et₂O washing for several times to obtain an intermediate product I-Py shown in the following formula 2:

j) under the condition of argon, the intermediate I-Py and PdCl obtained in the step I)₂(PPh₃)₂Dissolving CuI in triethylamine, adding F1 after a few minutes, and reacting at room temperature; after the reaction is completed, adding proper amount of saturated NH₄And (3) quenching the reaction by using a Cl solution, adding DCM for multiple times of extraction, removing the solvent by reduced pressure distillation, and carrying out column chromatography separation by using aluminum trioxide to obtain an orange solid, namely FP 1.

Preferably, the molar ratio of the DM to the (trimethylsilylethynyl) benzaldehyde and the sodium methoxide in the step a) is 1: 1.2: 6; the solution heating temperature is 70 ℃, and the reaction time is 3 h.

Preferably, in step c) and step f), DCM is added for extraction three times, and after the products are combined, anhydrous Na is added₂SO₄And (5) drying.

Preferably, F1, o-iodobenzyl alcohol and PdCl in step e)₂(PPh₃)₂And the molar ratio of CuI is 1:1.3:0.04: 0.04;

preferably, the molar ratio of the p-iodobenzaldehyde to the 2-acetylpyridine in the step h) is 1: 2.

preferably, the strong base used in step i) is potassium hydroxide, and the molar amount of the potassium hydroxide is 1.2 times of that of the p-iodobenzaldehyde; the ammonia water has a concentration of 25% and the same amount as ethanol, and is slowly added into the solution in small amount for multiple times.

Preferably, the molar ratio of the intermediate I-Py to F1 in step j) is 1:1.1, PdCl₂(PPh₃)₂And CuI were both 1% mmol.

Preferably, the column chromatography eluent in the step c) is dichloromethane and petroleum ether, and the volume ratio of the dichloromethane to the petroleum ether is 1: 1; the column chromatography eluting agent used in the step f) is dichloromethane and petroleum ether, and the volume ratio is 2: 1. the column chromatography eluent used in the step j) is dichloromethane and methanol, and the volume ratio is 100: 1.

the synthetic route of the fluorescent probe FP1 disclosed by the invention is as follows:

the third aspect of the invention provides the application of the fluorophore F1-F5 and the fluorescent probe FP1, and specifically comprises the application of the fluorophore F1-F5 in the preparation of an AIE effect-based detection reagent, and the application of the fluorescent probe FP1 in the preparation of Cu²⁺The FP1 is selectively complexed with copper ions, so that the reagent can be applied to detecting the copper ions in the environment.

The mechanism of the invention is as follows:

dicyanomethylene-4H-pyran (DM) is excellent in photophysical properties: the emission wavelength can be adjusted, the fluorescence quantum yield is high, the light stability is good, and the like, but when most derivatives of the derivatives are aggregated in a solution, pi-pi stacking interaction between aromatic ring molecules of adjacent luminophores is strong, and after the aggregates are excited, the excited state of the aggregates is usually decayed or relaxed back to the ground state through a non-radiative channel, so that the aggregation fluorescence quenching (ACQ) phenomenon of different degrees can be caused. The present invention obtains the fluorophore F1-F5 at F by modifying DM_w90% of THF-H₂And O is mixed in the solution. Except F3, the fluorescent probe FP1 is obtained by connecting F1 with a recognition group terpyridine²⁺After selective complexation, fluorescence quenching is performed, so that the method can be used for Cu in solution²⁺Selective detection of (2).

In addition, FP1 in the invention detects Cu²⁺In the method, the dosage of the organic solvent THF is small (about 10%), and other common anions and cations in the solution have little influence on the detection of copper ions.

Drawings

FIG. 1 shows F1 (10. mu.M) at gradient F_wUltraviolet absorption spectra in the mixed solution;

FIG. 2 shows F1 (10. mu.M) at gradient F_wFluorescence emission spectra in mixed solution;

FIG. 3 shows F2(10 μ M) at gradient F_wUltraviolet absorption spectra in the mixed solution;

FIG. 4 shows F2(10 μ M) at gradient F_wFluorescence emission spectra in mixed solution;

FIG. 5 shows F3(10 μ M) at gradient F_wUltraviolet absorption spectra in the mixed solution;

FIG. 6 shows F3(10 μ M) at gradient F_wFluorescence emission spectra in mixed solution;

FIG. 7 shows F4(10 μ M) at gradient F_wUltraviolet absorption spectra in the mixed solution;

FIG. 8 shows F4(10 μ M) at gradient F_wFluorescence emission spectra in mixed solution;

FIG. 9 shows F5(10 μ M) at gradient F_wUltraviolet absorption spectra in the mixed solution;

FIG. 10 shows F5(10 μ M) at gradient F_wFluorescence emission spectra in mixed solution;

FIG. 11 shows FP1(10 μ M) at gradient f_wUltraviolet absorption spectra in the mixed solution;

FIG. 12 shows FP1 (10. mu.M) at gradient f_wFluorescence emission spectra in mixed solution;

FIG. 13 shows FP1(10 μ M) at f after addition of various cations_w90% of THF-H₂Fluorescence emission spectra in O mixed solution;

FIG. 14 shows FP1 (10. mu.M) at f after addition of various anions_w90% of THF-H₂Fluorescence emission spectra in O mixed solution;

FIG. 15 shows FP1(10 μ M) at f after addition of gradient equivalents of copper ions_w90% of THF-H₂Fluorescence emission spectra in O mixed solution;

FIG. 16 is a graph showing the change in fluorescence intensity of FP1 (10. mu.M) at 612nm after addition of gradient equivalent copper ions;

FIG. 17 shows Cu at 612nm²⁺Concentration and amount of fluorescence change (F)₀-F) of the relationship curve.

Detailed Description

The following is a detailed description of embodiments of the invention. The embodiment is implemented on the premise of the technical scheme of the invention, and a detailed implementation mode and a specific operation process are given, but the protection scope of the invention is not limited to the following embodiment.

Various modifications to the precise description of the invention will be readily apparent to those skilled in the art from the information contained herein without departing from the spirit and scope of the appended claims. It is to be understood that the scope of the invention is not limited to the procedures, properties, or components defined, as these embodiments, as well as others described, are intended to be merely illustrative of particular aspects of the invention. Indeed, various modifications of the embodiments of the invention which are obvious to those skilled in the art or related fields are intended to be covered by the scope of the appended claims.

For a better understanding of the invention, and not as a limitation on the scope thereof, all numbers expressing quantities, percentages, and other numerical values used in this application are to be understood as being modified in all instances by the term "about". Accordingly, unless expressly indicated otherwise, the numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained. At the very least, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

A DM-based fluorophore of this example, F1-F5 with AIE Effect, fluorescence quenching Cu²⁺The chemical structural formula of the fluorescent probe FP1 is shown in formula 1.

Fluorophore F1-F5, fluorescence quenching type Cu²⁺The fluorescent probe FP1 was synthesized by the following steps:

preparation of F1: a dry 100mL Schleck bottle was taken, and DM (2.0mmol,416mg), p- (trimethylsilylethynyl) benzaldehyde (2.4mmol,485.5mg), and sodium methoxide (12.0mmol,648.1mg) were added under Ar gas protection, 12mL of anhydrous methanol was added after purging once, and the mixture was heated to 70 ℃ for reaction for 3 hours. TLC monitored the progress of the reaction, and after completion of the reaction, the reaction mixture was poured into ice water, diluted hydrochloric acid was added to a solution pH of 4, and the solution was extracted with DCM (3 × 30mL), and after combining, anhydrous Na was added₂SO₄Drying, distilling under reduced pressure to obtain solid, and separating by column chromatography. Developing agent PE: DCM ═ 1:1. 501mg of a yellow solid are obtained in 77% yield.

Preparation of F2: a dry 100mL Schleck flask was taken and the compound DM (0.5mmol,104mg), p-vinylbenzaldehyde (0.55mmol,73mg) were dissolved in 2mL of anhydrous acetonitrile under Ar gas, 0.05mL of piperidine was added and the mixture was heated to 85 ℃ and stirred for 12 h. TLC monitored the progress of the reaction, after completion of the reaction, MeCN was distilled off under reduced pressure and column chromatography separated to give 150mg of a yellow solid in 93% yield with PE as a developing solvent, DCM 2: 1.

Preparation of F3: a dry 100mL Schleck bottle was taken and the compound DM (0.5mmol,104mg), benzaldehyde (0.55mmol,58mg) were dissolved in 2mL of anhydrous acetonitrile under Ar gas, 0.05mL of piperidine was added and the mixture was heated to 85 ℃ and stirred for 12 h. The reaction progress was monitored by TLC, after completion of the reaction, the solvent was distilled off under reduced pressure and column chromatography gave 48mg of a yellow solid in 32% yield with the developing solvent PE: DCM ═ 2: 1.

Preparation of F4: a dry 50mL Schleck bottle was charged with o-iodobenzyl alcohol (1.47mmol,345mg), PdCl in Ar₂(PPh₃)₂(0.045mmol,32mg), CuI (0.045mmol,8mg), 15mL redistilled triethylamine, 10mL redistilled THF. After 5min F1(1.13mmol,363mg) was added, stirred at room temperature for 12h and the progress of the reaction was monitored by TLC. After the reaction is completed, adding proper amount of saturated NH₄The reaction was quenched with Cl solution, extracted with DCM (3X 30mL), combined and added with anhydrous Na₂SO₄After drying and removal of the solvent by distillation under the reduced pressure, column chromatography separation gave 410mg of a pink solid. Developing solvent DCM, PE 2: 1. The yield was 85%.

Preparation of F5: taking a dry 25mL Schleck bottle, in Ar gas atmosphere, o-iodomethyl anisole (0.12mmol,30mg), PdCl was added₂(PPh₃)₂(0.004mmol,3mg), CuI (0.004mmol,1mg), 5mL redistilled triethylamine, 5mL redistilled THF. After 5min F1(0.1mmol,32mg) was added and the reaction was allowed to proceed at room temperature for 12h and monitored by TLC. After confirming the completion of the reaction, an appropriate amount of saturated NH was added₄The reaction was quenched with Cl solution, extracted with DCM (3X 30mL), combined and added with anhydrous Na₂SO₄Drying, distilling under reduced pressure to remove the solvent, and separating by column chromatography to obtain orange solid 24mg and developing agent DCM: PE ═ 1:1. The yield was 55%.

Preparation of intermediate I-Py: a dry 250mL three-necked flask was charged with p-iodobenzaldehyde (10.0mmol,1.16g), 2-acetylpyridine (20mmol,1.22g), 50mL ethanol was added and stirred until the solid was completely dissolved, KOH (12.0mmol,0.78g), 50mL aqueous ammonia (25%) were added to the solution in small portions, slowly, stirred at reflux for 24h, and the progress of the reaction was monitored by TLC. After the reaction was complete, the flask was cooled to room temperature, the suspension was filtered off with suction and then dehydrated Et was used₂O three times to give 1.235g of a pale yellow solid, 57% yield.

Synthesis of Probe FP 1: a dry 50mL Schleck bottle was taken and added with I-Py (0.34mmol,147.0mg), PdCl under Ar gas₂(PPh₃)₂(0.01mmol,8mg), CuI (0.01mmol,2mg), 10mL of redistilled triethylamine, 10mL of anhydrous THF. After 5min, F1(0.28mmol,90mg) was added and the reaction was carried out at room temperature for 12h, and the progress of the reaction was monitored by TLC. After the reaction is completed, adding proper amount of saturated NH₄The reaction was quenched with Cl solution, extracted with DCM (3X 30mL), combined and taken over anhydrous Na₂SO₄Drying, removing the solvent by distillation under the reduced pressure, and separating by column chromatography using aluminum trioxide to give 126mg of an orange solid. Developing solvent DCM: MeOH: 100: 1. The yield was 72%.

F1-F5, I-Py and PF1 are subjected to nuclear magnetic and mass spectrometry respectively, and the test results are as follows:

F1:¹H NMR(400MHz,CDCl₃,25℃)：δ8.93(d,J＝8.4Hz,1H),7.76(t,J＝7.6Hz,1H),7.61(d,J＝16.0Hz,1H),7.57(s,5H),7.47(t,J＝8.1Hz,1H),6.90(s,1H),6.84(d,J＝15.9Hz,1H),3.23(s,1H).¹³C NMR(151MHz,CDCl₃,25℃)：δ157.0,152.7,152.3,137.7,134.9,134.8,132.8,127.7,126.1,125.9,124.1,119.8,118.6,117.8,116.6,107.4,83.1,79.7.HRMS(EI,TOF):calcd for C₂₂H₁₂N₂O⁺[M]⁺:320.0944,found:320.0949.

F2:¹H NMR(400MHz,CDCl₃,25℃)：δ8.92(d,J＝8.4,Hz,1H),7.75(t,J＝7.8Hz,1H),7.62(d,J＝16.0Hz,1H),7.57(d,J＝8.3Hz,3H),7.50-7.43(m,3H),6.88(s,1H),6.82(d,J＝16.0Hz,1H),6.75(dd,J＝17.6,10.9Hz,1H),5.86(d,J＝17.6Hz,1H),5.37(d,J＝10.8Hz,1H).¹³C NMR(101MHz,CDCl₃,25℃)：δ157.5,152.9,152.4,139.9,138.5,136.1,134.8,134.1,132.5,128.4,127.0,126.1,125.9,118.7,118.5,117.9,116.9,115.8,107.1,107.0,62.9.HRMS(EI,TOF):calcd for C₂₂H₁₄N₂O⁺[M]⁺:322.1101,found:322.1109.

F3:¹H NMR(400MHz,CDCl₃,25℃)：δ8.93(d,J＝8.4Hz,1H),7.76(t,J＝7.0Hz,1H),7.65(d,J＝16.0Hz,1H),7.62-7.56(m,3H),7.50-7.40(m,4H),6.89(s,1H),6.84(d,J＝16.0Hz,1H).¹³C NMR(151MHz,CDCl₃,25℃)：δ157.5,153.0,152.4,139.0,134.8,134.7,130.7,129.3,128.1,126.1,125.9,118.8,117.9,116.9,115.8,107.1,107.0,63.0.HRMS(EI,TOF):calcd for C₂₀H₁₂N₂O⁺[M]⁺:296.0944,found:296.0949.

F4:¹H NMR(400MHz,CDCl₃,25℃)：δ8.93(d,J＝8.4Hz,1H),7.77(t,J＝7.6Hz,1H),7.60(m,7H),7.52(d,J＝7.6Hz,1H),7.48(t,J＝7.5Hz,1H),7.41(t,J＝7.1Hz,1H),7.32(t,J＝7.6Hz,1H),6.91(s,1H),6.87(d,J＝16.0Hz,1H),4.95(d,J＝6.3Hz,2H),2.03(t,J＝6.4Hz,1H).¹³C NMR(151MHz,CDCl₃,25℃)：157.2,152.5,137.9,134.9,132.5,132.4,129.3,128.1,127.8,127.5,126.2,126.0,121.1,119.7,118.8,118.0,115.7,107.5,89.6,64.1.HRMS(EI,TOF):calcd for C₂₉H₁₈N₂O₂ ⁺[M]⁺:426.1363,found:426.1367.

F5:¹H NMR(400MHz,CDCl₃,25℃)：δ8.93(d,J＝8.2Hz,1H),7.76(t,J＝7.9Hz,1H),7.65-7.54(m,7H),7.53-7.44(m,2H),7.39(t,J＝7.3Hz,1H),7.30(t,J＝7.5Hz,1H),6.91(s,1H),6.85(d,J＝16.0Hz,1H),4.72(s,2H),3.50(s,3H).¹³C NMR(101MHz,CDCl₃,25℃)：δ157.2,152.9,152.4,140.2,138.0,134.9,132.3,127.0,127.8,127.6,126.2,126.0,125.5,118.8,118.0,116.8,115.8,90.0,72.8,58.8.HRMS(EI,TOF):calcd for C₃₀H₂₀N₂O₂ ⁺[M]⁺:440.1519,found:440.1527.

I-Py：¹H NMR(400MHz,CDCl₃,25℃)：δ8.73(d,J＝3.5Hz,2H),8.69(s,2H),8.67(d,J＝8.0Hz,2H),7.88(td,J＝7.7,1.6Hz,2H),7.84(d,J＝8.4Hz,2H),7.64(d,J＝8.4Hz,2H),7.37(d,J＝5.4Hz,1H),7.35(d,J＝5.0Hz,1H).

PF1：¹H NMR(400MHz,CDCl₃,25℃)：δ8.92(d,J＝7.8Hz,1H),8.75(d,J＝7.1Hz,4H),8.69(d,J＝8.0Hz,2H),7.95-7.88(m,4H),7.75(t,J＝7.7Hz,1H),7.69(d,J＝8.3Hz,2H),7.61(m,5H),7.56(d,J＝7.6Hz,1H),7.47(td,J＝8.2Hz,1H),7.39(d,J＝4.9Hz,1H),7.37(d,J＝5.3Hz,1H),6.89(s,1H),6.85(d,J＝15.9Hz,1H).¹³C NMR(151MHz,CDCl₃,25℃)：δ157.4,156.4,153.1,152.6,149.6,149.5,138.9,138.2,137.3,135.1,134.8,132.7,132.6,128.2,127.7,126.4,126.2,125.6,124.3,123.9,121.7,119.8,119.0,118.2,117.0,115.9,107.6,92.3,90.8,63.6.HRMS(ESI,TOF):calcd for C₄₃H₂₆N₅O⁺[M+H]⁺:628.2132,found:628.2139.

in conclusion, the nuclear magnetism and mass spectrum test results can confirm that the target compound is successfully prepared by the method.

The ultraviolet absorption and fluorescence emission spectrum tests are respectively carried out on F1-F5 and PF 1: THF was used as a solvent, and the appropriate amount of F1 was dissolved in a 25mL volumetric flask. Taking a proper amount of mother liquor, and adding THF-H₂O is solvent, the water content is 0%, 10%, 30%, 50%, 60%, 70%, 80% and 90% in sequence, and the materials are respectively prepared into 1 × 10 in a 25mL volumetric flask^-5M, in a solution to be tested.

F2-F5 and PF1 to-be-tested solutions are prepared as above.

According to FIGS. 1, 3 and 5, the specific gravity (f) of water in the mixed solvent is varied_w) The ultraviolet absorption changes obviously when the ultraviolet absorption increases continuously. f. of_wWhen the concentration is less than or equal to 70 percent, the ultraviolet-visible absorption spectra of all the compounds are very similar, the fine structure of electron pi-pi transition is shown between the wavelength of 400-500nm, and the two main peaks are respectively 420nm and 440 nm. As fw increases, the fine structure disappears and the uv absorption appears blue-shifted to different degrees. Ultraviolet absorption peaks of the compounds F1, F2 and F3 are 395nm, 321nm and 318nm respectively.

Fluorescence emission spectra of fluorophores F1-F3 with 420nm as excitation wavelength. According to FIGS. 2, 4 and 6, f_wWhen the content is more than or equal to 70%, fluorescence appears. When fw is 90%, F1 appears aggregation and sedimentation, solid is separated out on the wall of the volumetric flask, and the fluorescence intensity is reduced to some extent; f. of_wAt 80%, the fluorescence intensity of F1 reached a maximum. The fluorescence intensity in purer THF increased 58-fold;

fluorescence emission spectra of fluorophore F1-F3 with 420nm as excitation wavelength, with F_wThe fluorescence emission of F1 and F2 is increased and obviously mutated. f. of_wWhen the concentration is 90%, F1 is subjected to aggregation and sedimentation, solid is separated out from the wall of the volumetric flask, and the fluorescence intensity is reduced to some extent; f. of_wAt 80%, the fluorescence intensity of F1 reached a maximum. F2 and F3 are both at F_wWhen 90% was reached, the fluorescence intensity increased to the maximum. Exclusion of F1 at F_wThe interference data which is precipitated when the concentration is 90% is gradually transferred from pure THF solution to THF-H₂F1 fluorescence intensity is F in O mixed solution_wThe fluorescence intensity is increased by 58 times compared with that in pure water when 80 percent reaches the maximum; f2 the fluorescence intensity of which is lower than that of F_wAt 90%, the maximum autofluorescence was reached, with a 73-fold increase in pure THF, with AIE properties most pronounced in the three compounds. F3 lowest fluorescence intensity, F_wThe maximum value of the fluorescence intensity was 90%, but the intensity was only about 10% of the intensity of F2 in the same state. Total fluorescence enhancement degree F2>F1>F3, F1, F2 and F3 emission peaks are respectively as follows: 594nm, 566nm, 569 nm. The F1 fluorescence emission was most red-shifted and the intensity was highest.

To improve the water solubility of F1, hydroxyl is introduced into the system to obtain F4, and the hydroxyl of F4 is methylatedF5 was obtained. The ultraviolet spectra of F4 and F5 are substantially the same. f. of_wWhen the absorption spectrum is less than or equal to 70 percent, the ultraviolet-visible absorption spectra of F4 and F5 also show the fine structure of electron pi-pi transition between the wavelength of 400 and 500nm, and the absorption peaks are respectively as follows: 425nm and 448nm (FIGS. 7 and 9). Fluorescence emission spectrum was measured at 448nm as excitation wavelength, with f_wGradually increasing, gradually increasing fluorescence intensity, F4, F5 showing strong AIE effect, F4 emission red shift to 619nm, F_wAt 90%, the fluorescence intensity increased 149-fold compared to pure THF. Methoxy is a good electron-donating group, so f_wAt 90%, the peak of fluorescence emission was 659nm, which is clearly red-shifted compared to F4, and the fluorescence intensity was increased 92-fold compared to pure THF (fig. 8 and 10).

f_wWhen the concentration is less than 70 percent, a group of peaks of the ultraviolet-visible absorption spectrum of FP1 between the wavelength of 400-500nm are formed by electron pi-pi transition, and a fine structure appears, and the two main peaks are 426nm and 450nm respectively. With f_wGradually blurring the fine structure and red-shifting the uv absorption (fig. 11). FP1 fluorescence emission spectrum was tested with 426nm as excitation wavelength. In the following f_wWhen the peak value is increased to 70%, a fluorescence emission peak appears at 605nm, the fluorescence property of the solution is changed suddenly, the fluorescence intensity reaches the maximum in the solution with fw being 90%, the enhancement is 48 times compared with that in the pure THF solution, and the Stokes shift is 179nm (figure 12).

Selective assay of Probe FP 1:

we select f_w90% of THF-H₂O mixed solvent to characterize the ion selectivity of FP 1. Taking a proper amount of CuCl₂、SnCl₂、MnCl₂、FeCl₃、CoCl₂、NiCl₂、ZnCl₂、MgCl₂、CaCl₂、KCl、AgNO₃、CrCl₄NaCl solid dissolved in H₂In the mixed solvent of O-THF (9:1), the preparation concentration is 3X 10^-2Cu of M²⁺、Sn²⁺、Mn²⁺、Fe³⁺、Co²⁺、Ni²⁺、Zn²⁺、Mg²⁺、Ca²⁺、K⁺、Ag⁺、Cr⁴⁺、Na⁺10mL of the solution. Taking a proper amount of FP1 to be detectedAnd (3) dripping 2-3 drops of the salt solution into the quartz cuvette, and testing after uniformly mixing.

The fluorescence spectrum of the above mixed solution was measured at an excitation wavelength of 446 nm. Containing Cu²⁺The fluorescence emission of the liquid to be detected is almost 0, while the fluorescence intensity of the solution containing other metal ions is still higher, and although the intensity is reduced to different degrees, the influence can be ignored. FP1 can be implemented for Cu²⁺Selective detection (fig. 13).

To the solution to be tested of FP1, 1.5 times equivalent of cupric chloride was added, followed by addition of 10 times equivalent of another anionic solution. A fluorescence emission spectrum was obtained. When a large amount of F is present in the solvent^-、CI^-、Br^-、SO₄ ^2-、NO₃ ^2-、H₂PO₄ ^-There was no significant recovery of FP1 fluorescence emission, so the above common anions had no effect on copper ion detection in aqueous solution (fig. 14).

We chose 426nm as the excitation wavelength to study FP1 fluorescence intensity and Cu²⁺The relationship of concentration. THF-H for preparing copper chloride₂O(f_w90%) at a concentration of 1.0 mM. Respectively taking 3mL of FP1 solution to be tested and 3-42 mu L of Cu²⁺The solution was mixed well and left to stand for 5min, and the fluorescence emission spectrum was measured (FIG. 15).

With Cu²⁺The equivalent weight is increased, and the fluorescence emission intensity of FP1 is decreased. Cu added with fluorescence intensity as ordinate²⁺The equivalent of (2) is plotted on the abscissa, and a relationship curve between the two is obtained (FIG. 16). It can be seen that when 1.0 equivalent of Cu is added²⁺When the fluorescence of FP1 was almost completely quenched, the fluorescence emission intensity of FP1 hardly changed any more when the excess copper ion solution was added. Therefore, the complex ratio of the probe to the copper ions should be 1:1.

The emission wavelength is 612nm, and correspondingly different equivalent weights of Cu are added²⁺Fluorescence intensity of (I) with no addition of Cu²⁺Fluorescence intensity of (1)₀The difference value of (A) is the ordinate, the copper ion concentration is the abscissa, the first order relation curve (figure 17) can be obtained, the linear correlation coefficient is 0.9776, the standard deviation is 71279, the slope of the curve is 2.2810¹¹. The detection limit given by the international union of theory and applied chemistry is equal to 3 sigma/k, so that the detection limit of FP1 on copper ions is 2.1 multiplied by 10^-6M。