A kind of tetraphenyl ethene-3,4-dihydropyrimidine-2-ketone compound and its preparation method and application

Abstract

The application discloses a tetraphenyl ethene-3,4-dihydropyrimidine-2-ketone compound and a preparation method and application thereof, and the compound has the following structural formula: The application ingeniously proposes a compound with novel structure, and the compound not only has strong fluorescence characteristics, but also can exhibit significant responsiveness to multiple stimulations such as mechanical force, acid and alkali and light, thereby bringing new breakthroughs and opportunities for research in the fields of chemistry and material science.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluorescent materials, in particular to a tetraphenyl ethene-3,4-dihydropyrimidine-2-ketone compound, a preparation method and application thereof. BACKGROUND

[0002] In the field of chemistry and materials science, compounds with multiple stimuli responses have attracted much attention due to their unique properties. Such compounds can exhibit significant property changes under different external stimuli, such as light, heat, electricity, pH changes, etc., thus showing great application potential in the fields of sensors, drug delivery, optoelectronic devices, etc. In order to achieve multiple stimuli responses of the compounds, researchers often introduce different functional groups to achieve this goal.

[0003] Among the many functional groups, nitrogen heterocycles are widely used in the design of multiple stimuli response compounds due to their unique chemical properties. Nitrogen heterocycles can endow compounds with excellent electron transport performance and reactivity, thus achieving rapid response to external stimuli. However, in addition to nitrogen heterocycles, the introduction of other functional groups such as amino, carboxyl and hydroxyl groups is also important, as they can endow the compounds with different physical and chemical properties, thus expanding the application range of the compounds.

[0004] In the process of exploring new multiple stimuli response compounds, 3,4-dihydropyrimidine-2(1H)-ketone (DHPM) compounds with imine groups have gradually attracted the interest of researchers. Such compounds have shown good biological activity and pharmacological value in the field of drug research and development, especially in the development of anticancer drugs. However, in the molecular design of AIE (aggregation-induced emission) compounds, DHPM compounds are rarely reported.

[0005] The imine group of DHPM compounds is basic and can undergo protonation reaction with acids, thus realizing the acid-base responsiveness of the compounds. Therefore, if the molecular structure is designed skillfully, combining tetraphenyl ethene with 3,4-dihydropyrimidine-2(1H)-ketone (DHPM) compounds, it is expected to prepare a new type of tetraphenyl ethene-3,4-dihydropyrimidine-2(1H)-ketone (DHPM) compound. This new compound not only may have AIE properties, but also can exhibit multiple stimuli response through the protonation reaction of the imine group, bringing new opportunities for the development of sensors, drug delivery, optoelectronic devices, etc. SUMMARY

[0006] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a tetraphenyl ethene-3,4-dihydropyrimidine-2-ketone compound, which not only has good AIE effect, but also has multiple stimuli response.

[0007] The application also provides a preparation method of the compound.

[0008] The application also provides an application of the compound.

[0009] According to one aspect of the application, a tetraphenylethylene-3,4-dihydropyrimidin-2-one compound is provided, which has the following structural formula:

[0010]

[0011] According to a preferred embodiment of the application, at least the following advantages are provided: the application ingeniously provides a novel compound with strong fluorescence characteristics and significant responsiveness to mechanical force, acid-base and light stimuli. The design of the compound ingeniously combines tetraphenylethylene (TPE) with 3,4-dihydropyrimidin-2(1H)-one (DHPM) compounds, thereby endowing it with unique physical and chemical properties. For example, under the action of mechanical force, the compound exhibits pressure-induced fluorescence color change characteristics. When subjected to external mechanical pressure, the fluorescence color of the compound changes significantly from blue to green, which is obvious and easy to observe. This pressure-induced fluorescence color change phenomenon not only provides new possibilities for mechanical sensors, but also brings new perspectives to the research in the field of material science. Secondly, the compound is also sensitive to acid-base stimuli. When subjected to acid stimulation, the fluorescence emission wavelength of the compound shows a significant 18nm blue shift due to the inhibition of intramolecular ICT (intramolecular charge transfer) process. This acid-base responsiveness makes the compound have potential application value in pH sensors and drug delivery systems. In addition, the compound also has the property of photochromism. When the TPE-DHPM compound is sufficiently ground and then subjected to acid vapor fumigation, its fluorescence color will change under external light. This photochromic property not only increases the functional diversity of the compound, but also provides new material options for optoelectronic devices and optical storage. More importantly, under the external multiple stimuli, the compound can exhibit four different fluorescence color changes: deep blue, blue, green and yellow. This multiple stimulus responsiveness makes the compound have broad application prospects in the fields of sensors, smart materials, etc. By precisely controlling the external stimulus conditions, the fluorescence color of the compound can be precisely controlled, thereby realizing the detection and response to different environmental or biological signals. Therefore, the TPE-DHPM compound provided by the application has strong fluorescence characteristics and multiple stimulus responsiveness, which brings new breakthroughs and opportunities to the research in the fields of chemistry and material science.

[0012] According to another aspect of the application, a preparation method of the compound is provided, which comprises the following steps:

[0013] The tetraphenyl ethene-3,4-dihydropyrimidin-2-one compound is prepared by reacting 1,1,2-triphenyl-2-(4-formaldehyde phenyl) ethylene (TPEA) with urea and acetylacetone under a protective atmosphere.

[0014] The preparation method according to the preferred embodiment of the present application has at least the following beneficial effects: the present application introduces DHPM by the Biginelli reaction to synthesize the TPE-DHPM compound, and the preparation method is simple in operation and has good industrial application prospect.

[0015] In some embodiments of the present application, the protective atmosphere is nitrogen or inert gas atmosphere.

[0016] In some embodiments of the present application, the reaction is carried out under catalytic conditions, and the catalyst used in the catalysis includes magnesium chloride and an acid selected from the group consisting of glacial acetic acid, sulfuric acid and hydrochloric acid.

[0017] In some embodiments of the present application, the reaction temperature is 75-85 DEG C. For example, the temperature is 78 DEG C.

[0018] In some embodiments of the present application, the reaction time is 20-28 h. For example, the reaction time is 24 h.

[0019] In some embodiments of the present application, the reaction is carried out in solution, and the solvent used in the solution is ethanol.

[0020] In some embodiments of the present application, the preparation method further includes a post-treatment step, and the post-treatment step specifically includes collecting the reaction product and washing the reaction product with ethanol.

[0021] According to still another aspect of the present application, a tetraphenyl ethene-3,4-dihydropyrimidin-2-one compound single crystal is provided, and the single crystal belongs to monoclinic system and has non-central symmetric P21 space group.

[0022] According to still another aspect of the present application, a preparation method of the single crystal is provided, and the preparation method includes the following steps:

[0023] The single crystal is obtained from a mixed solution of THF and methanol by solvent evaporation method, and the volume ratio of THF to methanol in the mixed solution is 1:1-1:2.

[0024] The single crystal of the tetraphenyl ethene-3,4-dihydropyrimidin-2-one compound can emit blue light (λ em = 458 nm) by solvent evaporation method.

[0025] According to still another aspect of the present application, the application of the compound in preparing fluorescent materials is provided.

[0026] According to another aspect of the present application, the compound is applied in the field of detection or anti-counterfeiting.

[0027] In some embodiments of the present application, the detection includes at least one of the following detection contents:

[0028] 1) acidic substance;

[0029] 2) basic substance;

[0030] 3) product defect;

[0031] 4) stress.

[0032] In some embodiments of the present application, the detection includes the following steps: applying the detection content to the compound, irradiating the compound by a UV light source as an excitation light source, and observing the fluorescence change.

[0033] In some embodiments of the present application, the detection method can be applied to the surface or the inside of the product to be detected without complex operations such as photopolymerization, and the detection method has the advantages of simple operation, high detection efficiency, batch full automation, and good industrial application prospect.

[0034] In some preferred embodiments of the present application, the application includes at least one of coating, dipping, and fumigation. The detection content is applied to the surface of the product to be detected by coating, dipping, or fumigation, and the operation is simple.

[0035] In some preferred embodiments of the present application, the wavelength of the UV light source is 320-405 nm; preferably 345-385 nm; and more preferably 365 nm.

[0036] According to another aspect of the present application, a material includes the compound;

[0037] The material can be used to prepare at least one of the following products:

[0038] 1) toy;

[0039] 2) shape memory material;

[0040] 3) impact-resistant protective material;

[0041] 4) force sensor material;

[0042] 5) mechanical probe material;

[0043] 6) optical switch material;

[0044] 7) anti-counterfeiting material;

[0045] 8) flexible electronic product;

[0046] 9) Intelligent packaging materials;

[0047] 10) Acid-base testing materials.

[0048] According to the application of a preferred embodiment of the present invention, there are at least the following beneficial effects: the compound of the present invention has strong aggregated fluorescence. At the same time, under the stimulation of external force or acid, its fluorescence emission wavelength will undergo a red shift and the fluorescence color will change. It has good application prospects in the fields of acid and stress detection and anti-counterfeiting.

[0049] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments with reference to the following drawings, in which:

[0051] Figure 1 This is a preparation route for the compound of Example 1 of the present invention.

[0052] Figure 2 The product obtained in Example 1 of the present invention 1 HNMR (deuterated chloroform).

[0053] Figure 3 The product obtained in Example 1 of the present invention 13 CNMR (deuterated chloroform).

[0054] Figure 4 Emission and absorption spectra of the product prepared in Example 1 of the present invention corresponding to different water contents in a tetrahydrofuran solution / water mixture: a) Fluorescence spectrum, the inset is a fluorescence photograph under 365 nm UV light irradiation (bottom); b) UV-visible spectrum (concentration: 10 μM).

[0055] Figure 5 a) is the crystal structure of TPE-DHPM prepared in Example 2 of the present invention; b) is the fluorescence spectrum of the compound TPE-DHPM prepared in Example 1 after grinding and fumigation;

[0056] Figure 6 These are the PL spectra and fluorescence microscope photos of the product obtained in Example 1 of the present invention under external stimulation: a) is the initial powder; b) is the powder after grinding.

[0057] Figure 7 The original sample of the product prepared in Example 1 of the present invention a) is treated with hydrochloric acid vapor and then irradiated with ultraviolet light; b) TPE-DHPM (10-5 UV-Vis absorption spectrum of the dichloromethane solution of M) after exposure to UV light at 365 nm after addition of HCl.

[0058] Figure 8 are the analytical data of the single crystal prepared in Example 2 of the present application: a) 1B single crystal packing model simulation diagram; b) 1B single crystal weak interaction analysis object labeling diagram; c) 1B single crystal photocyclization reaction distance measurement result diagram. DETAILED DESCRIPTION

[0059] The concept and the technical effects produced by the present application will be described below in conjunction with the examples, so as to fully understand the purpose, features and effects of the present application. Obviously, the described examples are only a part of the examples of the present application, but not all the examples. Based on the examples of the present application, other examples obtained by those skilled in the art without creative labor are within the protection scope of the present application. The test methods used in the examples are conventional methods unless otherwise specified. The materials, reagents, etc. used in the examples are commercially available unless otherwise specified. The same parameters are used in the same way in each example unless otherwise specified. The examples described below are exemplary and are used to explain the present application, and cannot be understood as limiting the present application.

[0060] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the exemplary description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0061] Some of the raw materials used in the following examples and comparative examples are shown in Table 1 below:

[0062] Table 1

[0063]

[0064] The instrument information used in the following examples and comparative examples is shown in Table 2 below:

[0065] Table 2

[0066]

[0067] The methods and main parameter information used in the test characterization process are as follows:

[0068] Compound 1H-NMR and 13 C-NMR was measured on a Bruker AVANCE NEO 500 spectrometer with deuterated chloroform as solvent, tetramethylsilane (TMS) as internal standard, to test the chemical structure of the compound.

[0069] Fluorescence spectrum and ultraviolet-visible absorption spectrum were used to analyze the photophysical properties of the compound. The excitation and emission slits of the fluorescence spectrum for AIE performance test were 10 nm and 15 nm, and the rest were 3 nm and 5 nm.

[0070] X-ray diffractometer with Cu Kα (λ = 0.1541 nm) as light source, test voltage 40 kV, 40 mA, was used to characterize the aggregate structure of the compound.

[0071] Steady-state / transient combined fluorescence spectrometer and calibrated integrating sphere tested the fluorescence quantum efficiency of the compound.

[0072] X-ray single crystal diffractometer was used to collect crystal data, and X-ray was generated by Cu-Kα The structure was solved by direct method, and the full matrix least squares method was refined using SHELXTL package. Among them, the anisotropic refinement was carried out for non-hydrogen atoms.

[0073] Scanning electron microscope was used to observe the microstructure of the fiber membrane, and the operating voltage was 15 kV.

[0074] TPEA can be self-made (referring to the literature Iminoboronate-based peptide cyclization that responds to pH, oxidation, and small molecule modulators [J]. Journal of the American Chemical Society, 2016, 138 (7): 2098-2101. Preparation), and can also be purchased with cas number 1289218-74-1.

[0075] Under nitrogen protection, add BTPE (3.35 g, 10 mmol) and 4-FPBA (1.5 g, 10 mmol), add 20 mL THF, heat the mixture to 90 °C until the raw material is dissolved. Add 0.5 mmol TBAB and 18 mL aqueous solution containing 0.036 mol potassium carbonate, stir the mixture in the three-necked flask for 30 min. Then add Pd(PPh3)4(0.12 g, 0.1 mmol), track the reaction by thin layer chromatography until the raw material disappears. After cooling to room temperature (25 °C), mix the prepared reaction solution in the three-necked flask with a mixture of water and ethyl acetate (volume ratio 1:3) and extract three times, collect the organic solution. After drying with anhydrous sodium sulfate, obtain the solid product by rotary evaporator. Purify the crude product on a silica gel chromatographic column with a mixture of DCM and n-hexane (volume ratio 1:2) to obtain pure solid product TPEA (3.23 g, yield 89%).

[0076]

[0077] Repeat the above operation several times, mix the prepared product, and use it for the preparation of the product in the following examples.

[0078] Example 1

[0079] In this example, a tetraphenylethene-3,4-dihydropyrimidine-2-one compound TPE-DHPM is prepared. Its synthesis route is shown in Figure 1 Specific process: add TPEA (0.50 g, 1.38 mmol) to 30 mL anhydrous ethanol and heat and stir. After TPEA is fully dissolved, add catalyst anhydrous magnesium chloride (0.015 g, 0.138 mmol) and glacial acetic acid (9 mL, 30% ethanol) and continue to stir at 78 °C for 10 min, add urea (0.13 g, 2.08 mmol) and acetylacetone (0.138 g, 1.38 mmol) to the three-necked flask, and react for 24 h. After filtration, wash the filter residue with ethanol repeatedly 3 times to obtain white powder (0.4 g, 80%).

[0080] 1 H NMR (500 MHz, Chloroform-d) δ 8.01 (s, 1H), 7.14 - 6.94 (m, 18H), 5.58 (d, J = 2.5 Hz, 1H), 5.32 (d, J = 2.8 Hz, 1H), 2.32 (s, 3H), 2.03 (s, 3H). 13C NMR (151 MHz, CDC13) δ 194.35, 151.93, 148.13, 143.11, 142.23, 140.61, 140.24, 130.77, 130.61, 127.84, 127.79, 126.60, 126.51, 126.04, 109.13, 53.60, 30.11, 19.65.

[0081] NMR characterization data are shown in Figures 2-3

[0082] Example 2

[0083] In this example, a single crystal of a tetraphenylethene-3,4-dihydropyrimidine-2- ketone compound TPE-DHPM was prepared. At room temperature, a single crystal with blue light emission (λ em = 458 nm) was obtained by solvent evaporation method from THF / methanol (volume ratio of 1:1 or 1:2, 1:1 was used in this example).

[0084] Test Example

[0085] In this test example, the performance of the tetraphenylethene-3,4-dihydropyrimidine-2-ketone compound and its single crystal prepared in the example were tested. Among them:

[0086] 1. AIE performance test

[0087] The emission and absorption spectra of compound TPE-DHPM in different water content tetrahydrofuran / water mixed solutions are shown in Figure 4 From Figure 4 it can be seen that the fluorescence intensity of compound TPE-DHPM in tetrahydrofuran / water mixed solution with water content less than 80% is weak and changes little with the change of water content. When the water content of the system is greater than or equal to 80%, the fluorescence intensity of TPE-DHPM begins to increase; when the water content is 90%, the fluorescence intensity is about 100 times stronger than in pure tetrahydrofuran. At the same time, in the ultraviolet-visible absorption spectrum, when the water content is less than 80%, there is basically no change in the long wave direction. When the water content is greater than or equal to 80%, the long wave direction of the ultraviolet-visible absorption spectrum appears tailing phenomenon, which is caused by Mie effect. It can be seen that the change trend of the fluorescence spectrum and the ultraviolet-visible absorption spectrum of TPE-DHPM compound in different water content systems is consistent.

[0088] 2. Test of mechanochromic performance

[0089] Due to the highly twisted spatial structure of tetraphenylethene, the molecular packing is relatively loose (as shown in Figure 5 a)), which is easy to be stimulated by the outside world, thereby changing its packing mode. From Figure 5 ​The initial powder of TPE-DHPM shows blue fluorescence emission (λ em = 470 nm), and after grinding the initial powder, the fluorescence color changes from initial light blue to green, and the fluorescence maximum emission wavelength also red shifts from 470 nm in the initial state to 493 nm, with a red shift of 23 nm. The fluorescence color of the ground sample can be restored to the initial state after dichloromethane vapor fumigation, indicating that the mechanochromic properties of TPE-DHPM are reversible.

[0090] 3. Acid-base stimulus-responsive properties

[0091] Because of the imine group on the TPE-DHPM compound, we studied its acid stimulus response. At 25°C, a small amount of hydrochloric acid solution or ammonia water was placed in a closed desiccator (hydrochloric acid aqueous solution was used, with a HCl content of 36% to 38%; the base solution used ammonia water, with a NH3 content of 25% to 28%. Take 10 to 15 ml of hydrochloric acid or ammonia solution and place it in a desiccator of about 6.28 liters, at room temperature (about 25°C) and wait for about 30 minutes, the container can be filled with acid or base vapor), after the acid and ammonia vapor filled the desiccator, the sample was placed in a petri dish and placed in the desiccator, a 365 nm UV lamp was used to observe the fluorescence change, and the response time was recorded.

[0092] As shown in Figure 6 After the initial powder of TPE-DHPM was fumigated with hydrochloric acid vapor, its fluorescence color changed significantly: from the initial light blue fluorescence to deep blue fluorescence, and the emission wavelength also blue shifted from the initial 474 nm to 456 nm, indicating that the solid powder of TPE-DHPM has obvious acid stimulus response. Subsequently, the Pristine-HCl powder was fumigated with ammonia vapor, and the sample returned to the initial state. This is due to the protonation to deprotonation transition of the imine group of the TPE-DHPM compound. To explore whether the acid-base stimulus response behavior can be adjusted by changing the intermolecular packing mode, we studied the acid stimulus response of the ground sample. As shown in Figure 6 The hydrochloric acid vapor can also significantly change the fluorescence emission of the ground sample, with a blue shift of the emission wavelength from 493 nm to 473 nm, and the sample can return to the initial state after deprotonation with ammonia vapor. The blue shift of the fluorescence emission wavelength after hydrochloric acid fumigation is mainly because TPE-DHPM is a D-A structure, with an ICT effect from TPE to DHPM. After protonation, the lone pair electrons of the imine group on the DHPM unit are occupied, changing from electron-donating to electron-withdrawing, which blocks the generation of the ICT effect, resulting in a blue shift of the fluorescence after HCl fumigation.

[0093] 4. Test of photochromic properties

[0094] After fully grinding the powder, fumigating it with hydrochloric acid vapor, and irradiating it under ultraviolet light (~4s), the fluorescence color changed from green to yellow. Once the ultraviolet light was turned off, in a dark environment, after more than ten hours, the yellow fluorescence gradually faded to the original green. However, no photochromic phenomenon was observed in the pristine powder after being fumigated with hydrochloric acid vapor (such as Figure 7 However, photochromism generally occurs in the crystalline state rather than the amorphous state. In order to further study the photochromic properties of the fully ground powder after hydrochloric acid vapor fumigation, the UV-visible spectrum test was performed (as shown in FIG. Figure 7 It was found that after UV irradiation, a strong absorption band appeared in the visible light region, and the conjugation degree of the molecule increased.

[0095] 5) Single crystal

[0096] Crystal 1B belongs to the monoclinic system and has a non-centrosymmetric P21 space group. At the same time, the double bonds in the TPE skeleton are disordered, and the benzene rings on TPE present a highly distorted conformation (such as Figure 5 As shown in (a), the twisted TPE unit increases the steric hindrance, making the molecules relatively loosely packed, and no π...π interaction is observed. In the 1B crystal, two adjacent 1B molecules are stacked in parallel in a head-to-head manner along the c-axis ( Figure 8 As shown in a). Figure 8 As shown in b), there are 7 intermolecular interactions on the TPE backbone, and on the DHPM unit, CN┄O CH┄O and CH┄π There are 15 kinds of interaction forces between 22 molecules (as shown in Table 3).

[0097] Table 3

[0098]

[0099] As can be seen from Table 3, there are multiple intermolecular interactions between each molecule and its neighboring molecules, which make it form a more rigid molecular conformation. The distance between the possible photocyclization reaction sites of the TPE-DHPM compound is (like Figure 8 c), and the distance between the reported photocyclization reaction sites of TPE or triphenylethylene derivatives ( to ) similar. However, the photochromic property was not observed in the crystalline state, which can be attributed to the strong intermolecular interaction, making the molecular conformation more rigid, and the conformational adjustment of the photocyclization reaction is inhibited. When fully ground to the state of scraping, the crystalline order of the TPE-DHPM compound is transformed into amorphous state, the intermolecular interaction is destroyed, and at the same time, the molecular slip may be accompanied, so the internal rotation of the benzene ring on the TPE unit becomes possible, and the energy barrier of the formation of the photochromic intermediate is reduced due to the shortening of the bond length after protonation, resulting in the appearance of the photochromic phenomenon.

[0100] In summary, the TPE-DHPM compound is synthesized according to the scheme of the present application, which can respond to mechanical force, acid-base and light. The pressure-induced fluorescence color change under mechanical force is obvious, from the initial blue fluorescence to green fluorescence. When acid stimulation response is performed, the fluorescence emission wavelength shows a blue shift of 18 nm due to the inhibition of ICT. After the TPE-DHPM compound is fully ground, the photochromic property is exhibited after acid vapor fumigation. Under multiple external stimuli, the fluorescence color changes from deep blue, blue, green and yellow.

[0101] The above has made a detailed description of the embodiments of the present application, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge range possessed by those skilled in the art without departing from the purpose of the present application.

Claims

1. A tetraphenylstilbene-3,4-dihydropyrimidin-2-one compound, characterized by: The compound has the following structural formula: 。 2. The method of claim 1, wherein: The method comprises the following steps: The tetraphenyl ethene-3,4-dihydropyrimidine-2-ketone compound is prepared by reacting 1,1,2-triphenyl-2-(4-formaldehyde phenyl) ethylene with urea and acetylacetone under a protective atmosphere; the reaction comprises the following conditions: 1) the protective atmosphere is nitrogen or inert gas atmosphere; 2) the reaction is carried out under catalytic conditions, the catalyst used in the catalysis is magnesium chloride and acid, and the acid is selected from the group consisting of glacial acetic acid, sulfuric acid and hydrochloric acid; 3) the temperature of the reaction is 75-85 DEG C; 4) the reaction time is 20-28 h; 5) the reaction is carried out in a solution state, and the solution state uses ethanol as a solvent.

3. The application of the compound of claim 1 in preparing fluorescent materials.

4. Use of a compound according to claim 1 in the field of detection, characterized in that: The detection comprises at least one of the following detection contents: 1) acidic substance; 2) alkaline substance; 3) product defect; 4) stress.

5. Use according to claim 4, characterized in that: The detection comprises the following steps: applying the detection content to the compound, irradiating the compound by using an ultraviolet light source as an excitation light source, and observing the fluorescence change; the application comprises at least one of coating, dipping and fumigation; and the wavelength of the ultraviolet light source is 320-405 nm.

6. Use according to claim 5, characterized in that: The wavelength of the ultraviolet light source is 345-385 nm.

7. Use according to claim 5, characterized in that: The wavelength of the ultraviolet light source is 365 nm.

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