4-methylpyridine diterminated benzene diimide and hexafluorosilicate eutectic supramolecule as well as preparation method and application of 4-methylpyridine diterminated benzene diimide and hexafluorosilicate eutectic supramolecule

Abstract

The invention provides a 4-methylpyridine diterminated benzene diimide and hexafluorosilicate eutectic supramolecule as well as a preparation method and application thereof, and belongs to the technical field of p-phenylenediamine fluorescence detection. The preparation method comprises the following steps: mixing 4-methylpyridine diterminated benzene diimide and hexafluorosilicate in a mixed solvent, and then carrying out solvothermal reaction to obtain the 4-methylpyridine diterminated benzene diimide and hexafluorosilicate eutectic supramolecule. The 4-methylpyridine two-end group benzene diimide and hexafluorosilicate eutectic supramolecule encounters p-phenylenediamine molecules, p-phenylenediamine and benzene diimide generate hydrogen-bond interaction under the synergistic effect of hexafluorosilicate, the characteristic of quenching benzene diimide fluorescence is achieved, and the eutectic supramolecule can be used as a fluorescence detection p-phenylenediamine reagent, can be used for fluorescence detection of p-phenylenediamine, can be used for fluorescence detection of p-phenylenediamine, and can be used for fluorescence detection of p-phenylenediamine. The operation is simple and the detection effect is good.

Description

Technical Field

[0001] The invention relates to the technical field of p-phenylenediamine fluorescence detection, and in particular to a 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule, and a preparation method and application thereof. Background Art

[0002] As an organic environmental pollutant, p-phenylenediamine is highly toxic. It enters the human body through inhalation, ingestion, and skin penetration, forming highly nucleophilic oxidation products that interact with DNA and increase the probability of cell canceration, causing serious damage to the nervous system, blood system, liver, etc., leading to cancers of the lymphatic system, urinary system, skin, breast, thyroid and liver. P-phenylenediamine is also a strong sensitizer. Long-term contact will cause toxic metabolism to deposit in the body, causing contact dermatitis and eczema, which is harmful to human health. P-phenylenediamine is widely used in industrial production such as rubber, dyes, detergents and defense, such as anti-aging agents for synthetic rubber, azo dyes, hair dyes, hair dyes, etc. Due to its low cost and good coloring effect, p-phenylenediamine is often used in hair dyes. About 70% of hair dyes are added with p-phenylenediamine. P-phenylenediamine compounds are one of the items that must be monitored in industrial wastewater such as textiles, dyes, and pharmaceuticals.

[0003] At present, the main methods for detecting p-phenylenediamine include spectrophotometry, liquid chromatography, gas chromatography, electrochemical methods, etc. The above methods have problems such as environmental pollution, cumbersome operation, and high cost. Fluorescence detection methods have attracted the attention of detection researchers due to their simple operation, high efficiency and sensitivity, good selectivity, and low detection limit. Fluorescence detection reagents refer to those with characteristic fluorescence in the ultraviolet-visible light region, and the fluorescence properties change with changes in the external environment. Therefore, it is of great significance to study a eutectic supramolecular compound for detecting p-phenylenediamine. Summary of the invention

[0004] The object of the present invention is to provide a 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule and a preparation method and application thereof, so as to solve the problem of complicated operation and high cost of p-phenylenediamine detection in the prior art.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The invention provides a method for preparing a 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule, comprising the following steps: mixing the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate in a mixed solvent, and then performing a solvent thermal reaction to obtain the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule.

[0007] Preferably, the hexafluorosilicate comprises sodium hexafluorosilicate, ammonium hexafluorosilicate or potassium hexafluorosilicate.

[0008] Preferably, the mixed solvent comprises chloroform and ethanol, wherein the volume ratio of chloroform to ethanol is 3 to 10:2.

[0009] Preferably, the molar volume ratio of the 4-methylpyridine di-terminal phthalimide, hexafluorosilicate and mixed solvent is 0.08-0.12 mmol: 0.08-0.20 mmol: 8-12 mL.

[0010] Preferably, the temperature of the solvent thermal reaction is 80-90° C. and the time is 48-78 hours.

[0011] Preferably, the mixture obtained by mixing 4-methylpyridine di-terminal phthalimide and hexafluorosilicate in a mixed solvent is adjusted to a pH value of 4 to 5 before the solvothermal reaction is carried out.

[0012] The present invention provides a eutectic supramolecule of the above-mentioned 4-methylpyridine di-terminal phthalimide and hexafluorosilicate.

[0013] The present invention provides an application of the above-mentioned 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule in fluorescence detection of p-phenylenediamine.

[0014] Beneficial effects of the present invention:

[0015] (1) When the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecules of the present invention encounter p-phenylenediamine molecules, under the synergistic effect of hexafluorosilicate, p-phenylenediamine and phthalimide produce hydrogen bonding, which has the characteristic of quenching the fluorescence of phthalimide. The eutectic supramolecules of the present invention can be used as a reagent for fluorescence detection of p-phenylenediamine, which is simple to operate and has a good detection effect.

[0016] (2) The 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular synthesis yield of the present invention is high and the cost is low, and it has good application prospects in textiles, pharmaceuticals, dyes, rubber, chemicals, and environmental separation and detection of p-phenylenediamine.

[0017] (3) The aqueous solution of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular of the present invention is used as a fluorescence detection reagent for p-phenylenediamine, and has a fluorescence emission peak at 375 nm. The minimum concentration of p-phenylenediamine that can be detected by fluorescence is 10 -6 mol / L. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The single crystal structure diagram of the eutectic supramolecular of 4-methylpyridine di-terminal phthalimide and hexafluorosilicate of the present invention;

[0019] Figure 2This is a one-dimensional ladder chain supramolecular structure diagram of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular of the present invention;

[0020] Figure 3 The fluorescence emission spectra of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule in Example 1 in aqueous p-phenylenediamine solutions of different concentrations;

[0021] Figure 4 The ultraviolet absorption spectra of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule in Example 1 in aqueous p-phenylenediamine solutions of different concentrations. DETAILED DESCRIPTION

[0022] The invention provides a method for preparing a 4-methylpyridine di-terminal phthalimide (N,N′-bis(4-pyridylmethyl)-pyromellitic diimide) and hexafluorosilicate eutectic supramolecule, comprising the following steps: mixing the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate in a mixed solvent, and then performing a solvent thermal reaction to obtain the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule.

[0023] In the present invention, the hexafluorosilicate comprises sodium hexafluorosilicate, ammonium hexafluorosilicate or potassium hexafluorosilicate, preferably sodium hexafluorosilicate or ammonium hexafluorosilicate, and more preferably ammonium hexafluorosilicate.

[0024] In the present invention, the mixed solvent comprises chloroform and ethanol, wherein the volume ratio of chloroform to ethanol is 3 to 10:2, preferably 3 to 8:2, and more preferably 3 to 5:2.

[0025] In the present invention, the molar volume ratio of the 4-methylpyridine di-terminal phthalimide, hexafluorosilicate and mixed solvent is 0.08-0.12 mmol: 0.08-0.20 mmol: 8-12 mL, preferably 0.09-0.11 mmol: 0.09-0.17 mmol: 9-11 mL, and more preferably 0.10 mmol: 0.15-0.17 mmol: 10 mL.

[0026] In the present invention, the temperature of the solvothermal reaction is 80 to 90° C., preferably 85 to 90° C., and the time is 48 to 78 hours, preferably 60 to 76 hours, and more preferably 68 to 72 hours.

[0027] In the present invention, the mixture obtained by mixing 4-methylpyridine di-terminal phthalimide and hexafluorosilicate in a mixed solvent is adjusted to a pH value of 4 to 5 before the solvothermal reaction is carried out.

[0028] The present invention provides a eutectic supramolecule of the above-mentioned 4-methylpyridine di-terminal phthalimide and hexafluorosilicate.

[0029] The single crystal structure of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular of the present invention is as follows: Figure 1 As shown, its single crystal data is shown in Table 1:

[0030] Table 1 Single crystal data of 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular

[0031]

[0032]

[0033] The 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular of the present invention, adjacent 4-methylpyridine di-terminal phthalimide forms a one-dimensional ladder chain supramolecular structure through hydrogen bonding between pyridine rings and hexafluorosilicate. The structure is shown in the figure Figure 2 shown.

[0034] The present invention provides an application of the above-mentioned 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule in fluorescence detection of p-phenylenediamine.

[0035] The 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular is used as a fluorescence detection reagent for fluorescence detection of p-phenylenediamine in an aqueous solution.

[0036] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0037] In the examples, the diameter of the qualitative filter paper is 15.0 cm and is purchased from Fushun Minzheng Filter Paper Factory.

[0038] Example 1

[0039] 0.1mmol 4-methylpyridine di-terminal phthalimide and 0.15mmol ammonium hexafluorosilicate were placed in a 20mL reactor filled with 10mL of a mixed solvent (the volume ratio of chloroform and ethanol was 7:3), and a solvothermal reaction was carried out at 90°C for 72h. The reaction product was filtered with a qualitative filter paper, and the crystals were washed once with distilled water to obtain a eutectic supramolecule of 4-methylpyridine di-terminal phthalimide and hexafluorosilicate.

[0040] The mass of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule in this example is 209 mg, and the yield is 52.5%.

[0041] The elemental analysis of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular in this example showed that 22 H 16 N4O4F6Si, the theoretical calculated values ​​are C: 48.71%, H: 2.97%, N: 10.33%, the experimental values ​​are C: 48.56%, H: 3.21%, N: 10.12%; infrared spectrum: IR (KBr, cm -1 ): 3442vs, 2925w, 2854w, 1773m, 1722s, 1622m, 1385vs, 1343m, 1306, 1121m, 943w, 918w, 796w, 727w, 632w.

[0042] Example 2

[0043] 0.11mmol 4-methylpyridine di-terminal phthalimide and 0.09mmol ammonium hexafluorosilicate were placed in a 20mL reactor filled with 10mL of a mixed solvent (the volume ratio of chloroform and ethanol was 7:3), and the solvent thermal reaction was carried out at 90°C for 72h. The reaction product was filtered with a qualitative filter paper, and the crystals were washed once with distilled water to obtain a eutectic supramolecule of 4-methylpyridine di-terminal phthalimide and hexafluorosilicate.

[0044] The mass of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule in this example is 205 mg, and the yield is 51.5%.

[0045] Example 3

[0046] 0.1 mmol 4-methylpyridine di-terminal phthalimide and 0.17 mmol ammonium hexafluorosilicate were placed in a 20 mL reactor filled with 10 mL of a mixed solvent (the volume ratio of chloroform and ethanol was 8:2), the pH value was adjusted to 5.0, and the solvent thermal reaction was carried out at 85°C for 72 h. The reaction product was filtered with a qualitative filter paper, and the crystals were washed once with distilled water to obtain a 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule.

[0047] The mass of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule in this example is 230 mg, and the yield is 57.8%.

[0048] 1.0 μmol of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular solution of Example 1 was placed in 100 mL of water, and the solution was stirred at 25° C. for 20 min to obtain a 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular aqueous solution, which was used as a fluorescence detection reagent for p-phenylenediamine. -6 ~4×10 -5mol / L aqueous p-phenylenediamine solution (the concentration of p-phenylenediamine is 0.1×10 -5 mol / L、0.2×10 -5 mol / L、0.4×10 - 5 mol / L、0.6×10 -5 mol / L、0.8×10 -5 mol / L、1.0×10 -5 mol / L、1.2×10 -5 mol / L、1.6×10 -5 mol / L、2.0×10 -5 mol / L、4.0×10 -5 mol / L), and the fluorescence emission spectrum of the test solution. The fluorescence emission spectrum of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular after adding p-phenylenediamine in Example 1 is as follows Figure 3 As shown. Figure 3 It can be seen that it emits fluorescence under 285nm excitation light, and the maximum emission wavelength is at 375nm; under the synergistic effect of hexafluorosilicate, 4-methylpyridine di-terminal phthalimide forms a hydrogen bond with p-phenylenediamine, quenching the fluorescence emission spectrum of 4-methylpyridine di-terminal phthalimide. The minimum concentration of p-phenylenediamine that can be detected by fluorescence is 10 -6 The ultraviolet absorption spectra of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular added with different concentrations of p-phenylenediamine in Example 1 are shown in the figure below. Figure 4 As shown. Figure 4 It can be seen that when the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular is immersed in an aqueous solution containing p-phenylenediamine, the ultraviolet absorption peak at 320nm gradually weakens. Based on this principle, the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular of the present invention can be used for fluorescent detection of p-phenylenediamine in aqueous solution, and the operation is simple.

[0049] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecular, characterized in that: The method comprises the following steps: mixing 4-methylpyridine di-terminal phthalimide and hexafluorosilicate in a mixed solvent, and then performing a solvent thermal reaction to obtain a eutectic supramolecular of 4-methylpyridine di-terminal phthalimide and hexafluorosilicate.

2. The method for preparing the eutectic supramolecule of 4-methylpyridine di-terminal phthalimide and hexafluorosilicate according to claim 1, characterized in that: The hexafluorosilicate includes sodium hexafluorosilicate, ammonium hexafluorosilicate or potassium hexafluorosilicate.

3. The method for preparing the eutectic supramolecule of 4-methylpyridine di-terminal phthalimide and hexafluorosilicate according to claim 1 or 2, characterized in that: The mixed solvent comprises chloroform and ethanol, wherein the volume ratio of chloroform to ethanol is 3 to 10:

2.

4. The method for preparing the eutectic supramolecule of 4-methylpyridine di-terminal phthalimide and hexafluorosilicate according to claim 3, characterized in that: The molar volume ratio of the 4-methylpyridine di-terminal phthalimide, hexafluorosilicate and mixed solvent is 0.08-0.12 mmol: 0.08-0.20 mmol: 8-12 mL.

5. The method for preparing the eutectic supramolecule of 4-methylpyridine di-terminal phthalimide and hexafluorosilicate according to claim 1, 2 or 4, characterized in that: The temperature of the solvent thermal reaction is 80-90° C. and the time is 48-78 hours.

6. The method for preparing the eutectic supramolecule of 4-methylpyridine di-terminal phthalimide and hexafluorosilicate according to claim 5, characterized in that: The pH value of the mixture obtained by mixing 4-methylpyridine di-terminal phthalimide and hexafluorosilicate in a mixed solvent is adjusted to 4-5 before the solvent thermal reaction is carried out.

7. The eutectic supramolecule of 4-methylpyridine di-terminal phthalimide and hexafluorosilicate prepared by the method for preparing the eutectic supramolecule of 4-methylpyridine di-terminal phthalimide and hexafluorosilicate according to any one of claims 1 to 6.

8. Use of the 4-methylpyridine di-terminal phthalimide and hexafluorosilicate eutectic supramolecule according to claim 7 in fluorescence detection of p-phenylenediamine.

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