Boron-containing solid-liquid double-state fluorescent polymer material with solvent polarity responsiveness

Abstract

The invention discloses a boron-containing solid-liquid double-state fluorescent polymer material with solvent polarity responsiveness. The boron-containing solid-liquid double-state fluorescent polymer material with solvent polarity responsiveness can emit light in both solid and liquid states, and after the polymer is dissolved in organic solvents with different polarities, the solution fluorescence can be subjected to red shift along with the increase of the polarity of the solvents and can be subjected to red shift from cyan blue to yellow green. The invention also provides a preparation method of the boron-containing solid-liquid double-state fluorescent high polymer material with solvent polarity responsiveness, the synthesis method is simple in process, convenient to operate and low in cost, the application of the material in the field of fluorescence detection is greatly widened, and the material has a good application prospect on the basis of the unique and sensitive fluorescence response characteristic of the material to the solvent polarity. The fluorescent probe shows relatively important application potential in the fields of fluorescence sensing, chemical detection, microenvironment probes and the like, and is expected to be widely applied to the leading edge directions of environment monitoring, biomedical detection and the like.

Description

Technical Field

[0001] This invention belongs to the field of functional polymer materials technology, specifically relating to a boron-containing solid-liquid dual-state fluorescent polymer material with solvent polarity responsiveness. This material exhibits fluorescence properties in both solid and solution states and can be used for chemical sensing and environmental detection. Background Technology

[0002] Stimulus-responsive materials are a class of functional molecules or polymers that can generate response signals to changes in the external environment. Their responses can manifest as changes in optical properties, electronic characteristics, or mechanical properties. Among these, fluorescent materials that respond to chemical environments (such as pH, solvents, and ions) have attracted considerable attention due to their significant application potential in fields such as chemical sensing, environmental monitoring, and biological probes. Currently, although there are numerous reports on fluorescent materials that respond to single stimuli (such as acids and bases), research on material systems exhibiting sensitive and reversible fluorescence responses to the key physicochemical parameter of solvent polarity remains relatively limited. In particular, smart materials that can emit light efficiently in both solid and solution states, and whose fluorescence wavelengths exhibit a continuous and significant redshift with solvent polarity, have become a worthy research direction for further exploration in this field due to their irreplaceable advantages in recognition and detection, and microenvironment probes. Summary of the Invention

[0003] The present invention aims to provide a boron-containing solid-liquid dual-state fluorescent polymer material with solvent polarity responsiveness and its preparation method. The polymer material emits fluorescence in both solid and liquid states, and its solution fluorescence exhibits a highly sensitive response to solvent polarity, characterized by a significant and continuous redshift in fluorescence emission wavelength as solvent polarity increases. This material demonstrates the advantages of obvious and easily observable fluorescence signal changes, providing a new approach for developing novel chemical sensing and detection materials.

[0004] The objective of this invention is achieved through the following solution: On the one hand, this invention provides a boron-containing solid-liquid dual-state fluorescent polymer material with solvent polarity responsiveness, the structural formula of which is: ; Where: m is 5-50; n is 5-50; o is 5-50.

[0005] On the other hand, the present invention also provides a method for preparing the above-mentioned solvent-polar responsive boron-containing solid-liquid dual-state fluorescent polymer material, comprising the following preparation process:

[0006]

[0007] Step 1: In a reaction tube containing magnesium shavings under nitrogen protection, add monomer 4,4'-dichlorobenzophenone. The apparatus is evacuated and purged with nitrogen three times. Under nitrogen atmosphere, add trimethyl borate and dry tetrahydrofuran using a syringe. Stir magnetically at 60°C for 24 hours. Extract the organic phase with dichloromethane, add anhydrous magnesium sulfate, dry, and remove the solvent by rotary evaporation. Precipitate in petroleum ether and dry under vacuum to obtain a white solid powder, namely hyperbranched polydiphenylboronic acid. Step 2: In a nitrogen-protected reaction tube, add hyperbranched polydiphenylboronic acid I and 8-hydroxyquinoline. The apparatus is evacuated and purged with nitrogen three times. Under a nitrogen atmosphere, dry dichloromethane is added using a syringe. The reaction is magnetically stirred at room temperature for 24 hours. The organic phase is extracted with dichloromethane, dried with anhydrous magnesium sulfate, and the solvent is removed by rotary evaporation. The precipitate is precipitated in petroleum ether and dried under vacuum to obtain a yellow solid powder, which is the 8-hydroxyquinoline coordinated hyperbranched polydiphenylboronic acid polymer. The structural formula of hyperbranched polydiphenylboronic acid is:

[0008] The structural formula of monomer 4,4'-dichlorobenzophenone:

[0009] The structural formula of trimethyl borate monomer: .

[0010] The structural formula of the 8-hydroxyquinoline-coordinated hyperbranched polydiphenylboronic acid polymer:

[0011] Furthermore, the boron-containing solid-liquid dual-state fluorescent polymer with solvent polarity responsiveness is characterized in that: under 365nm ultraviolet light irradiation, the fluorescent polymer emits green fluorescence in the solid state with an emission wavelength of 495nm, and emits fluorescence of different colors depending on the solvent polarity in the dilute solution state, thus exhibiting dual-state luminescence properties in both solid and liquid states.

[0012] Furthermore, the boron-containing solid-liquid dual-state fluorescent polymer with solvent polarity responsiveness is characterized in that: after the fluorescent polymer is dissolved in organic solvents of different polarities, the fluorescence of the solution will red-shift as the solvent polarity increases, and can shift from cyan-blue to yellow-green.

[0013] Compared with the prior art, the present invention has the following advantages and beneficial effects: The boron-containing solid-liquid dual-state fluorescent polymer material involved in this invention has a novel chemical structure and exhibits stable fluorescence properties in both solid and liquid states. This material displays a highly sensitive response to solvent polarity; its fluorescence emission wavelength undergoes a significant and continuous redshift with increasing solvent polarity, offering advantages such as high responsiveness, obvious fluorescence signal changes, and ease of identification and observation. Attached Figure Description

[0014] Figure 1 This is the 1H NMR spectrum of the hyperbranched polydiphenylboronic acid synthesized in this invention; Figure 2 The 1H NMR spectrum of the 8-hydroxyquinoline-coordinated hyperbranched polydiphenylboronic acid polymer synthesized in this invention; Figure 3 The GPC curve of the hyperbranched polydiphenylboronic acid synthesized in this invention is shown below. Figure 4 The GPC curve of the 8-hydroxyquinoline-coordinated hyperbranched polydiphenylboronic acid polymer synthesized in this invention is shown below. Figure 5 This is a schematic diagram of the solid and solution fluorescence of the 8-hydroxyquinoline-coordinated hyperbranched polydiphenylboronic acid polymer in Example 2 of the present invention; Figure 6 This is a schematic diagram illustrating the fluorescence response behavior of the 8-hydroxyquinoline-coordinated hyperbranched polydiphenylboronic acid polymer in different polar solvents in Example 3 of the present invention. Detailed Implementation

[0015] This invention discloses a boron-containing hyperbranched fluorescent polymer material and a method for preparing the composite material formed by coordination with 8-hydroxyquinoline. The synthetic route uses dichlorobenzophenone, trimethyl borate, and magnesium as main raw materials. Hyperbranched polydiphenylboronic acid with a hyperbranched structure is constructed via a one-pot method, followed by a coordination reaction with 8-hydroxyquinoline to obtain the final product. This preparation process is simple and efficient, and the obtained product has a well-defined structure and excellent fluorescence properties. The obtained composite material emits fluorescence in both solid and solution states, and its solution fluorescence exhibits a sensitive response to solvent polarity, showing a continuous redshift in fluorescence emission wavelength with increasing solvent polarity. This demonstrates promising application prospects in the fields of chemical sensing and molecular recognition. See the following examples for details.

[0016] Example 1 A boron-containing solid-liquid dual-state fluorescent polymer compound exhibiting solvent polarity responsiveness has the following structural formula:

[0017] Where: m is 5-50; n is 5-50; o is 5-50.

[0018] The preparation method of the above-mentioned boron-containing solid-liquid dual-state fluorescent polymer compound with solvent polarity responsiveness includes the following preparation process:

[0019]

[0020] Step 1: Using 4,4'-dichlorobenzophenone and trimethyl borate as starting materials, 3.98 mmol (1000.46 mg) of 4,4'-dichlorobenzophenone was added to a reaction tube containing 9.56 mmol (231.38 mg) of magnesium shavings under nitrogen protection. Under a nitrogen atmosphere, 4 mL of dry tetrahydrofuran and 0.192 mmol (206.9 mg) of trimethyl borate were added using a syringe. The reaction was magnetically stirred at 60 °C for 24 hours. The organic phase was extracted with dichloromethane, dried with anhydrous magnesium sulfate, and the solvent was removed by rotary evaporation. The precipitate was precipitated in 60 mL of petroleum ether and dried under vacuum to obtain a white solid powder, namely hyperbranched polydiphenylboronic acid. The NMR spectrum is attached. Figure 1 The gel permeation chromatogram is shown in the attached figure. Figure 3 As shown; Step 2: In a nitrogen-protected reaction tube, add 500.33 mg of hyperbranched polydiphenylboronic acid and 478.55 mg of 8-hydroxyquinoline obtained in Step 1. The reaction tube is evacuated and purged with nitrogen three times. Under a nitrogen atmosphere, add 2 mL of dry dichloromethane using a syringe. Stir magnetically at room temperature for 24 hours. Extract the organic phase with dichloromethane, add anhydrous magnesium sulfate, dry, and then remove the solvent by rotary evaporation. Precipitate in petroleum ether and dry under vacuum to obtain a yellow solid powder, which is the 8-hydroxyquinoline-coordinated hyperbranched polydiphenylboronic acid polymer. The NMR spectrum is attached. Figure 2 The gel permeation chromatogram is shown in the attached figure. Figure 4 As shown; The structural formula of hyperbranched polydiphenylboronic acid is:

[0021] The structural formula of monomer 4,4'-dichlorobenzophenone:

[0022] The structural formula of trimethyl borate monomer:

[0023] The structural formula of the 8-hydroxyquinoline-coordinated hyperbranched polydiphenylboronic acid polymer: .

[0024] Example 2 The boron-containing solid-liquid dual-state fluorescent polymer material (8-hydroxyquinoline-coordinated hyperbranched polydiphenylboronic acid polymer) obtained in Example 1 was placed on a glass slide and photographed under 365 nm ultraviolet light. A bright green fluorescence was clearly observed. Simultaneously, the material was dissolved in DMF to prepare a 0.5 mg / mL solution, which was placed in a quartz cuvette and photographed under the same ultraviolet light conditions. The solution also emitted a clear yellow-green fluorescence. This set of comparative experimental photographic evidence fully confirms that the material possesses excellent fluorescence emission characteristics in both solid and solution states, as shown in the attached figure. Figure 5 As shown.

[0025] Example 3 The boron-containing solid-liquid dual-state fluorescent polymer (8-hydroxyquinoline-coordinated hyperbranched polydiphenylboronic acid polymer) obtained in Example 1 was dissolved in dichloromethane, tetrahydrofuran, pyridine, N-dimethylformamide, and dimethyl sulfoxide, respectively, to prepare a series of solutions with a concentration of 0.5 mg / mL. These solutions were placed in quartz cuvettes and photographed under 365 nm UV light. It was observed that as the solvent polarity increased from dichloromethane to dimethyl sulfoxide, the fluorescence of the solution exhibited a regular color change from cyan to yellow-green from left to right, with a significant red shift in the fluorescence emission wavelength. (See attached image.) Figure 6 As shown.

Claims

1. A boron-containing solid-liquid dual-state fluorescent polymer with solvent polarity responsiveness, characterized in that: The structure of the boron-containing solid-liquid dual-state fluorescent high polymer is as follows: ； wherein m is 5-50; n is 5-50; and o is 5-50.

2. The boron-containing solid-liquid two-state fluorescent polymer having solvent polarity responsiveness according to claim 1, wherein: ###0002### Under the irradiation of a 365 nm ultraviolet lamp, the boron-containing solid-liquid dual-state fluorescent high polymer emits green fluorescence in a solid state, and emits fluorescence of different colors in a dilute solution state according to the polarity of the solvent, and has the dual-state luminescence property of emitting light in both the solid state and the solution state.

3. The boron-containing solid-liquid dual-state fluorescent polymer with solvent polarity responsiveness as described in claim 1, characterized in that: After the boron-containing solid-liquid dual-state fluorescent high polymer is dissolved in organic solvents of different polarities, the solution fluorescence red-shifts with the increase of the solvent polarity, and can red-shift from cyan to yellow-green.

4. A preparation method of the boron-containing solid-liquid dual-state fluorescent high polymer with solvent polarity responsiveness according to any one of claims 1-3, comprising the following steps: ； ； Step 1: reacting 4,4'-dichlorobenzophenone and trimethyl borate with magnesium shavings in anhydrous tetrahydrofuran to obtain hyperbranched polydiphenyl borate; Step 2: reacting the hyperbranched polydiphenyl borate obtained in Step 1 with 8-hydroxyquinoline in dichloromethane, and precipitating the reaction product in petroleum ether to obtain 8-hydroxyquinoline-coordinated hyperbranched polydiphenyl borate polymer; wherein the structure of the hyperbranched polydiphenyl borate is as follows: ； the structure of the monomer 4,4'-dichlorobenzophenone is as follows: ； the structure of the monomer trimethyl borate is as follows: ； the structure of the 8-hydroxyquinoline-coordinated hyperbranched polydiphenyl borate polymer is as follows: 。 5. The method for preparing boron-containing solid-liquid state fluorescent polymer having solvent polarity responsiveness according to claim 4, characterized in that: and specifically comprising the following steps: Step 1: adding the monomer 4,4'-dichlorobenzophenone into a reaction tube containing magnesium shavings under nitrogen protection, vacuumizing and filling nitrogen for 3 times, adding trimethyl borate and dry tetrahydrofuran into the reaction tube by using a syringe under nitrogen atmosphere, magnetically stirring at 60°C for 24 hours, extracting the organic phase with dichloromethane, drying by adding anhydrous magnesium sulfate, and removing the solvent by rotary evaporation, precipitating in petroleum ether, and vacuum drying to obtain white solid powder, i.e. hyperbranched polydiphenyl borate; Step 2: adding the hyperbranched polydiphenyl borate prepared in Step 1 and 8-hydroxyquinoline into a reaction tube under nitrogen protection, vacuumizing and filling nitrogen for 3 times, adding dry dichloromethane into the reaction tube by using a syringe under nitrogen atmosphere, magnetically stirring at room temperature for 24 hours, extracting the organic phase with dichloromethane, drying by adding anhydrous magnesium sulfate, and removing the solvent by rotary evaporation, precipitating in petroleum ether, and vacuum drying to obtain yellow solid powder, i.e. 8-hydroxyquinoline-coordinated hyperbranched polydiphenyl borate.

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