Preparation method and application of castor oil-based multicolor fluorescent compound

Abstract

The present invention discloses a method for preparing a castor oil-based multicolor fluorescent compound and its application. Unconventional chromophores such as ester bonds with π electrons and amine groups with lone pairs of (n) electrons form high-concentration clusters through a large number of intramolecular and intermolecular hydrogen bonds, thereby causing electron cloud overlap and conformational rigidification. This behavior minimizes non-radiative energy loss and maximizes their radiative transition probability. And its Fe 3+ It has a sensitive fluorescence quenching effect and can be used to detect residual iron ions in water. The raw materials for the production process are easily available, the operation is simple, and the conditions are mild.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer material preparation, and specifically is a preparation method and application of castor oil-based multicolor fluorescent compounds Background Art

[0002] Traditional dyes or fluorescent molecules, such as oxadiazole and its derivatives, triazole and its derivatives, rhodamine and its derivatives, coumarin derivatives, etc., have a conjugated planar structure and strong intermolecular forces between molecules. The intramolecular electron transition dipole moment phenomenon generated by them leads to fluorescence quenching when they are in an aggregated state.

[0003] However, it has now been found that many chromophore-free synthetic compounds and natural biopolymers emit abnormal luminescence in an aggregated state, which is well-known as aggregation-induced emission (AIE). Academician Tang Benzhong pioneered the investigation and interpretation of AIE and further developed the spatial conjugation (TSC) mechanism. This mechanism suggests that at low concentrations, electron clouds are unlikely to overlap, resulting in weak or no emission. In contrast, unconventional chromophores with π and lone pairs (n) of electrons form clusters at high concentrations through a large number of intramolecular and intermolecular hydrogen bonds, resulting in electron cloud overlap and conformational rigidification. This behavior minimizes non-radiative energy losses and maximizes the probability of their radiative transitions. AIE materials have a very broad application prospect in the fields of three-dimensional high-density information storage, three-dimensional imaging of organisms, fluorescent labeling, fluorescent probes, etc. However, the molecules related to AIE are usually complex in structure design, poor in solubility, and mainly based on petroleum-based raw materials. The preparation of multicolor fluorescent compounds with readily available raw materials from bio-based sources, simple operation, and mild conditions is still a technical problem. Summary of the invention

[0004] Technical problem to be solved: The present invention provides a method for preparing and applying a castor oil-based multicolor fluorescent compound. Unconventional chromophores such as ester bonds with π electrons and amine groups with lone pairs of (n) electrons form high-concentration clusters through a large number of intramolecular and intermolecular hydrogen bonds, thereby causing electron cloud overlap and conformational rigidification. This type of compound has good solubility and processability and can be used to detect Fe in water. 3+ .

[0005] Technical solution: A method for preparing a castor oil-based multicolor fluorescent compound, comprising the following steps:

[0006] (1) Synthesis of castor oil allyl ester: Castor oil, an acid binder, an inhibitor and a solvent are added to a reaction vessel, and an allyl chloride compound is added dropwise at 0 to 5° C. After the addition is completed, the mixture is reacted at room temperature for 4 to 8 hours. After the reaction is completed, the mixture is washed with deionized water until the pH is neutral, and the organic phase is collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain an oily liquid castor oil allyl ester;

[0007] (2) Synthesis of castor oil-based polyamines: Castor oil allyl ester and primary amine compounds are added to a reaction vessel, a solvent and a catalyst are added, and the mixture is reacted under magnetic stirring at room temperature for 12 to 72 hours. After rotary evaporation, deionized water is added to wash the mixture until the pH is neutral. The organic phase is collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain a castor oil-based polyfluorescent compound.

[0008] In step (1), the allyl chloride compound is acryloyl chloride, methacryloyl chloride, diallylcarbamoyl chloride or 10-undecenoyl chloride.

[0009] In step (1), the molar ratio of the hydroxyl group of castor oil to the acyl chloride group of the allyl acyl chloride compound is 1:2 to 2.5.

[0010] In step (1), the acid binding agent is triethylamine; the polymerization inhibitor is hydroquinone; and the solvent is ethyl acetate or tetrahydrofuran.

[0011] In step (1), the molar ratio of the allyl chloride compound to the acid binding agent is 1:1-1.2; and the amount of the acid binding agent is 0.2 wt.%.

[0012] In step (2), the primary amino compound is any one of diethylenetriamine, pentamethylenediamine, aniline, 2-furylmethylamine, cyclopentylamine, ethylamine, tert-butylamine, dopamine, and methyl-levodopamine.

[0013] In step (2), the catalyst is anhydrous ferric chloride, anhydrous aluminum chloride, N-bromosuccinimide or sodium methoxide, and the solvent is tetrahydrofuran, ethyl acetate or dichloromethane.

[0014] In step (2), the molar ratio of allyl group to primary amine group in the castor oil allyl ester is 1:1-2; and the amount of catalyst added is 0.2wt.%.

[0015] The castor oil-based multicolor fluorescent compound prepared by the preparation method is effective in detecting Fe in water. 3+ Application in.

[0016] Beneficial effects: At present, there is no report on the synthesis method of preparing multicolor fluorescent compounds using castor oil as raw material in China. This invention is the first to do so. Unconventional chromophores such as ester bonds with π electrons and amine groups with lone pairs of (n) electrons form high-concentration clusters through a large number of intramolecular and intermolecular hydrogen bonds, thereby causing electron cloud overlap and conformational rigidity. This behavior minimizes non-radiative energy loss and maximizes their radiative transition probability. And its effect on Fe 3+The invention has a sensitive fluorescence quenching effect, and the compound has good solubility and processability, and can be used to detect residual iron ions in water. The product of the invention has excellent photophysical properties, with an optimal excitation wavelength of 425nm and a maximum multicolor fluorescence emission wavelength of 515nm. The invention uses castor oil as a raw material, has abundant raw material sources, low production costs, and conforms to the concepts of green environmental protection and sustainable development; in addition, the synthesis process is simple, operability is strong, and it is easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the light emitting principle of the present invention;

[0018] Figure 2 This is the NMR spectrum of the castor oil-based multicolor fluorescent compound obtained in Example 1 of the present invention;

[0019] Figure 3 Fluorescence emission spectra of the castor oil-based multicolor fluorescent compound obtained in Example 1 under different excitation lights;

[0020] Figure 4 This is the fluorescence emission spectrum of the castor oil-based multicolor fluorescent compound obtained in Example 1 of the present invention at 425 nm. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, rather than all embodiments.

[0022] A method for preparing a castor oil-based multicolor fluorescent compound is prepared by the following steps: (1) Synthesis of castor oil allyl ester: Castor oil, an acid binder, an inhibitor and a solvent are added to a four-necked flask, and an allyl chloride compound is added dropwise at 0-5°C. After the addition is completed, the mixture is reacted at room temperature for 4-8 hours. The molar ratio of the hydroxyl group to the acyl chloride group of castor oil is 1:(2-2.5). The molar ratio of the allyl chloride compound to the acid binder is 1:(1-1.2). The amount of the inhibitor added is 0.2wt.%. After the reaction is completed, the mixture is washed with deionized water until the pH is neutral, the organic phase is collected, the water is removed with anhydrous magnesium sulfate, and suction filtered to obtain an oily liquid castor oil allyl ester. (2) Synthesis of castor oil-based polyamine: Castor oil allyl ester and primary amine compound are added to a conical flask, and a solvent and 0.2 wt.% catalyst are added. The molar ratio of allyl group to primary amine group in the castor oil allyl ester is 1:(1-2). The reaction is carried out under magnetic stirring at room temperature for 12-72 hours. After rotary evaporation, deionized water is added to wash until the pH is neutral, and the organic phase is collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain a castor oil-based multicolor fluorescent compound.

[0023] Preferably, in step (1), the allyl chloride compound is acryloyl chloride, methacryloyl chloride, diallylcarbamoyl chloride or 10-undecenoyl chloride, and the molar ratio of the hydroxyl group of castor oil to the acyl chloride group of the allyl chloride compound is 1:2.2.

[0024] Preferably, in step (1), the acid-binding agent is triethylamine, and the molar ratio of the allyl chloride compound to the acid-binding agent is 1:1.1. The polymerization inhibitor is hydroquinone, and the dosage is 0.2 wt.%. The solvent is ethyl acetate or tetrahydrofuran.

[0025] Preferably, in step (2), the molar ratio of allyl group to primary amine group in the castor oil allyl ester is 1:1.5. The primary amine compound is any one of diethylenetriamine, pentamethylenediamine, aniline, 2-furylmethylamine, cyclopentylamine, ethylamine and tert-butylamine.

[0026] Preferably, in step (2), the catalyst is anhydrous ferric chloride, anhydrous aluminum chloride, N-bromosuccinimide (NBS) or sodium methoxide, and the added amount is 0.2 wt.%, and the solvent is tetrahydrofuran, ethyl acetate or dichloromethane.

[0027] The castor oil-based multicolor fluorescent compound prepared by the above synthesis method.

[0028] The above castor oil-based multicolor fluorescent compound is useful for detecting Fe in water. 3+ Application in.

[0029] Example 1

[0030] (1) Synthesis of castor oil allyl ester: 100 g of castor oil, 36 g of triethylamine, 0.22 g of hydroquinone and 300 ml of ethyl acetate were added to a four-necked flask, and 29.1 g of acryloyl chloride was added dropwise at 0°C. After the addition was completed, the mixture was reacted at room temperature for 6 h. After the reaction was completed, the mixture was washed with deionized water until the pH was neutral, the organic phase was collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain an oily liquid acrylated castor oil.

[0031] (2) Synthesis of castor oil-based multicolor fluorescent compound: 10 g of acrylated castor oil and 4.4 g of diethylenetriamine were added to a conical flask, and 0.003 g of anhydrous ferric chloride was added, and the mixture was stirred under magnetic stirring at room temperature for 24 hours. After rotary evaporation, deionized water was added to wash until the pH was neutral, and the organic phase was collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain diethylenetriamine castor oil-based fluorescent compound I.

[0032] (3) Application of castor oil-based multicolor fluorescent compounds in detecting Fe in water 3+ Application: Add 1 mol / l to 1×10 -15 mol / l Fe3+ The solution was sonicated for 30 s. The photoluminescence (excitation and emission) spectra were studied on an Agilent Cary Eclipse fluorescence spectrometer. The widths of the excitation and emission slits were 5 nm and 10 nm, respectively. The measurements were performed with a quartz cell with a 2 mm path under the excitation of a xenon discharge lamp and a scanning wavelength rate of 1200 nm / min. The incident light of 425 nm for different Fe 3+ Fluorescence spectrum of the solution. 3+ The concentration reaches 10 -8 mol / l, the fluorescence intensity decreased sensitively; when Fe 3+ The concentration reaches 10 -3 mol / l, the fluorescence is almost completely quenched.

[0033] Example 2

[0034] (1) Synthesis of castor oil allyl ester: 100 g of castor oil, 36 g of triethylamine, 0.22 g of hydroquinone and 300 ml of ethyl acetate were added to a four-necked flask, and 29.1 g of acryloyl chloride was added dropwise at 0°C. After the addition was completed, the mixture was reacted at room temperature for 6 h. After the reaction was completed, the mixture was washed with deionized water until the pH was neutral, the organic phase was collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain an oily liquid acrylated castor oil.

[0035] (2) Synthesis of castor oil-based multicolor fluorescent compound: 10 g of acrylated castor oil and 4.15 g of furfurylamine were added to a conical flask, and 0.003 g of anhydrous ferric chloride was added. The mixture was stirred under magnetic stirring at room temperature for 24 hours. After rotary evaporation, deionized water was added to wash until the pH was neutral. The organic phase was collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain a castor oil-based multicolor fluorescent compound.

[0036] (3) Application of castor oil-based multicolor fluorescent compounds in detecting Fe in water 3+ Application: Add 1 mol / l to 1×10 -15 mol / l Fe 3+ The solution was sonicated for 30 s. The photoluminescence (excitation and emission) spectra were studied on an Agilent Cary Eclipse fluorescence spectrometer. The widths of the excitation and emission slits were 5 nm and 10 nm, respectively. The measurements were performed with a quartz cell with a 2 mm path under the excitation of a xenon discharge lamp, and the scanning wavelength rate was 1200 nm / min. The fluorescence spectra of the solution were obtained without degassing. The incident light at 425 nm for different Fe 3+ Fluorescence spectrum of the solution. 3+ The concentration reaches 10 -6 mol / l, the fluorescence intensity decreased; when Fe3+ The concentration reaches 10 -1 mol / l, the fluorescence is almost completely quenched.

[0037] Example 3

[0038] (1) Synthesis of castor oil allyl ester: 100 g of castor oil, 36 g of triethylamine, 0.22 g of hydroquinone and 300 ml of ethyl acetate were added to a four-necked flask, and 36.96 g of methacryloyl chloride was added dropwise at 0°C. After the addition was completed, the mixture was reacted at room temperature for 6 h. After the reaction was completed, the mixture was washed with deionized water until the pH was neutral, the organic phase was collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain oily liquid castor oil allyl ester.

[0039] (2) Synthesis of castor oil-based multicolor fluorescent compound: 10 g of castor oil allyl ester and 3.66 g of diethylenetriamine were added to a conical flask, and 0.003 g of anhydrous ferric chloride was added. The mixture was stirred under magnetic stirring at room temperature for 24 hours. After rotary evaporation, deionized water was added to wash until the pH was neutral. The organic phase was collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain diethylenetriamine castor oil-based fluorescent compound II.

[0040] (3) Application of castor oil-based multicolor fluorescent compounds in detecting Fe in water 3+ Application: Add 1 mol / l to 1×10 -15 mol / l Fe 3+ The solution was sonicated for 30 s. The photoluminescence (excitation and emission) spectra were studied on an Agilent Cary Eclipse fluorescence spectrometer. The widths of the excitation and emission slits were 5 nm and 10 nm, respectively. The measurements were performed with a quartz cell with a 2 mm path under the excitation of a xenon discharge lamp, and the scanning wavelength rate was 1200 nm / min. The fluorescence spectra of the solution were obtained without degassing. The incident light at 425 nm for different Fe 3+ Fluorescence spectrum of the solution. 3+ The concentration reaches 10 -7 mol / l, the fluorescence intensity decreased sensitively; when Fe 3+ The concentration reaches 10 -2 mol / l, the fluorescence is almost completely quenched.

[0041] Example 4

[0042] (1) Synthesis of castor oil allyl ester: 100 g of castor oil, 36 g of triethylamine, 0.22 g of hydroquinone and 300 ml of ethyl acetate were added to a four-necked flask, and 39.96 g of methacryloyl chloride was added dropwise at 0°C. After the addition was completed, the mixture was reacted at room temperature for 6 h. After the reaction was completed, the mixture was washed with deionized water until the pH was neutral, the organic phase was collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain oily liquid castor oil allyl ester.

[0043] (2) Synthesis of castor oil-based multicolor fluorescent compound: 10 g of castor oil allyl ester and 3.3 g of aniline were added to a conical flask, and 0.003 g of anhydrous ferric chloride was added. The mixture was stirred under magnetic stirring at room temperature for 24 hours. After rotary evaporation, deionized water was added to wash until the pH was neutral. The organic phase was collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain a castor oil-based multicolor fluorescent compound.

[0044] (3) Application of castor oil-based multicolor fluorescent compounds in detecting Fe in water 3+ Application: Add 1 mol / l to 1×10 -15 mol / l Fe 3+ The solution was sonicated for 30 s. The photoluminescence (excitation and emission) spectra were studied on an Agilent Cary Eclipse fluorescence spectrometer. The widths of the excitation and emission slits were 5 nm and 10 nm, respectively. The measurements were performed with a quartz cell with a 2 mm path under the excitation of a xenon discharge lamp, and the scanning wavelength rate was 1200 nm / min. The fluorescence spectra of the solution were obtained without degassing. The incident light at 425 nm for different Fe 3+ Fluorescence spectrum of the solution. 3+ The concentration reaches 10 -9 mol / l, the fluorescence intensity decreased sensitively; when Fe 3+ The concentration reaches 10 -3 mol / l, the fluorescence is almost completely quenched.

[0045] Example 5

[0046] (1) Synthesis of castor oil allyl ester: 100 g of castor oil, 36 g of triethylamine, 0.22 g of hydroquinone and 300 ml of ethyl acetate were added to a four-necked flask, and 56.42 g of diallylcarbamoyl chloride was added dropwise at 0°C. After the addition was completed, the mixture was reacted at room temperature for 6 h. After the reaction was completed, the mixture was washed with deionized water until the pH was neutral, the organic phase was collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain oily liquid castor oil allyl ester.

[0047] (2) Synthesis of castor oil-based multicolor fluorescent compound: 10 g of castor oil allyl ester and 3.56 g of diethylenetriamine were added to a conical flask, and 0.1 g of anhydrous ferric chloride was added. The mixture was stirred under magnetic stirring at room temperature for 24 hours. After rotary evaporation, deionized water was added to wash until the pH was neutral. The organic phase was collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain diethylenetriamine castor oil-based fluorescent compound III.

[0048] (3) Application of castor oil-based multicolor fluorescent compounds in detecting Fe in water 3+ Application: Add 1 mol / l to 1×10 -15 mol / l Fe 3+ The solution was sonicated for 30 s. The photoluminescence (excitation and emission) spectra were studied on an Agilent Cary Eclipse fluorescence spectrometer. The widths of the excitation and emission slits were 5 nm and 10 nm, respectively. The measurements were performed with a quartz cell with a 2 mm path under the excitation of a xenon discharge lamp, and the scanning wavelength rate was 1200 nm / min. The fluorescence spectra of the solution were obtained without degassing. The incident light at 425 nm for different Fe 3+ Fluorescence spectrum of the solution. 3+ The concentration reaches 10 -10 mol / l, the fluorescence intensity decreased sensitively; when Fe 3+ The concentration reaches 10 -2 mol / l, the fluorescence is almost completely quenched.

[0049] The above examples are only for illustrating the technical concept and features of the present invention, and are only intended to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a castor oil-based multicolor fluorescent compound, characterized in that: The following steps are involved: (1) Synthesis of castor oil allyl ester: Castor oil, an acid binder, an inhibitor and a solvent are added to a reaction vessel, and an allyl chloride compound is added dropwise at 0-5°C. After the addition is completed, the mixture is reacted at room temperature for 4-8 hours. After the reaction is completed, the mixture is washed with deionized water until the pH value is neutral. The organic phase is collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain an oily liquid castor oil allyl ester. The allyl chloride compound is acryloyl chloride, methacryloyl chloride, or diallylcarbamoyl chloride. (2) Synthesis of castor oil-based polyamines: Castor oil allyl ester and primary amine compounds are added to a reaction vessel, and a solvent and a catalyst are added. The mixture is reacted under magnetic stirring at room temperature for 12 to 72 hours. After rotary evaporation, deionized water is added to wash the mixture until the pH is neutral. The organic phase is collected, dehydrated with anhydrous magnesium sulfate, and filtered to obtain a castor oil-based polyfluorescent compound. The primary amine compound is any one of diethylenetriamine, pentamethylenediamine, aniline, 2-furylmethylamine, cyclopentylamine, ethylamine, tert-butylamine, and dopamine. The catalyst is anhydrous ferric chloride or anhydrous aluminum chloride.

2. The method for preparing the castor oil-based multicolor fluorescent compound according to claim 1, characterized in that: In step (1), the molar ratio of the hydroxyl group of castor oil to the acyl chloride group of the allyl acyl chloride compound is 1:2-2.

5.

3. The method for preparing the castor oil-based multicolor fluorescent compound according to claim 1, characterized in that: In step (1), the acid binding agent is triethylamine; the polymerization inhibitor is hydroquinone; and the solvent is ethyl acetate or tetrahydrofuran.

4. The method for preparing the castor oil-based multicolor fluorescent compound according to claim 1, characterized in that: In step (1), the molar ratio of the allyl chloride compound to the acid binding agent is 1:1-1.2; and the amount of the acid binding agent is 0.2 wt.%.

5. The method for preparing the castor oil-based multicolor fluorescent compound according to claim 1, characterized in that: In step (2), the solvent is tetrahydrofuran, ethyl acetate or dichloromethane.

6. The method for preparing the castor oil-based multicolor fluorescent compound according to claim 1, characterized in that: In step (2), the molar ratio of allyl group to primary amine group in the castor oil allyl ester is 1:1-2; and the amount of catalyst added is 0.2 wt.%.

7. The castor oil-based multicolor fluorescent compound prepared by any one of the preparation methods of claims 1 to 6 is used to detect Fe in water. 3+ Application in.

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