Preparation of a cyanostyrene derivative and its application in information encryption and fingerprint recognition

Abstract

This application relates to the fields of organic light-emitting materials and information security technology, and more specifically, to the preparation of a cyanostylene derivative and its application in information encryption and fingerprint recognition. First, an oxaspirocyclic-bridged cyanostylene derivative, SDCS, was designed and synthesized. The cyanostylene groups at both ends of the molecule provide the fluorophore, while the oxaspirocyclic ring provides the rigid, twisted framework bridging the cyanostylene groups. Driven by supramolecular self-assembly, this single-component SDCS exhibits a time-dependent color change in fluorescence from orange to green over time in a CH3CN / H2O system; the higher the water content, the slower the color change rate. Utilizing this characteristic, SDCS can be applied to time-dependent information encryption and erasure, improving the security level of information storage. Furthermore, the dynamic fluorescence color of SDCS can be fixed by a solid matrix, achieving the characteristic of a single-component substance displaying two fixed fluorescence colors. Phosphors prepared using this feature can be used for single-component dual-color fingerprint imaging.

Description

Technical Field

[0001] This application relates to the fields of organic light-emitting materials and information security technology, and more specifically, it relates to the preparation of a cyano-styrene derivative and its application in information encryption and fingerprint recognition. Background Technology

[0002] Innovations in organic light-emitting materials are of great significance for the development of technologies such as bioimaging, information security, and optoelectronic devices. Dynamic control of molecular luminescence, especially time-dependent methods, has brought new opportunities for the development of advanced light-emitting materials. Supramolecular self-assembly provides an effective method for regulating the luminescence behavior of organic molecules. However, the luminescence changes during self-assembly of these systems typically occur over a very short timeframe, limiting their practical applications.

[0003] Therefore, developing dynamic luminescence based on single-component self-assembly on a controlled timescale remains a challenge. If organic molecules can exist in an initial kinetic state and then spontaneously transition to a thermodynamically stable state over time, it becomes possible to obtain time-dependent fluorescent materials. By immobilizing time-varying fluorescent materials within a solid matrix and preventing changes in assembly morphology, dual-color fluorescence of single-component molecules can be achieved. These characteristics can be leveraged to enable multifunctional applications of single-component fluorophores, such as time-dependent high-security information encryption and dual-color fingerprint imaging. Summary of the Invention

[0004] This disclosure provides a method for preparing a cyanostyl styrene derivative and its application in information encryption and fingerprint recognition. The synthesized molecule SDCS exhibits time-dependent fluorescence color change in the CH3CN / H2O system, with the fluorescence color changing from orange to green over time. Furthermore, its color change rate is negatively correlated with water content; that is, the higher the water content, the slower the color change rate. This characteristic can be applied to time-dependent information encryption and erasure, significantly improving the security level of data storage.

[0005] In a first aspect, this disclosure provides a cyanostrene derivative, wherein the derivative is synthesized into compound SDCS via a three-step reaction. The cyanostrene groups at both ends provide fluorophores for the molecule, and the oxaspirocyclic ring serves as a rigid, twisted framework bridging the cyanostrene. The structure of the compound SDCS is shown in formula (I).

[0006]

[0007] Preferably, the compound SDCS is prepared by dehydration condensation of compound a and compound b, and the reaction equation is as follows:

[0008]

[0009] The compound a is The compound b is The reaction conditions were as follows: under N2 atmosphere, compounds a and b were added to a flask, dissolved in 20 mL of EtOH, and the mixture was stirred at room temperature for 24 h until the reaction was complete. The mixture was then filtered to obtain a filter cake, which was dissolved in DCM, rotary evaporated, and dried under vacuum to obtain an orange solid SDCS.

[0010] Preferably, the SDCS molecules are ultrasonically transformed into orange fluorescent nanospheres in the CH3CN / H2O system. The orange fluorescent nanospheres exhibit time-dependent color-changing properties, with the fluorescence color changing from orange to green, and the structure of the orange fluorescent nanospheres changing from nanospheres to nanosheets.

[0011] Preferably, the test concentration of the CH3CN / H2O system is 10–200 μM, and the excitation wavelength of the CH3CN / H2O system is 310–380 nm.

[0012] Preferably, the preparation method of compound a includes the following steps: reacting p-hydroxyphenylacetonitrile and benzaldehyde at room temperature under NaOH / EtOH alkaline conditions to obtain the intermediate product 2-(4-hydroxyphenyl)-3-phenylacrylonitrile, then adding hexamethylenetetramine, using TFA / AcOH as solvent, and heating under reflux under nitrogen protection to prepare the compound a.

[0013] In the preparation of compound a, the molar ratio of p-hydroxyphenylacetonitrile, sodium hydroxide, and benzaldehyde is 1:2 to 2.5:1 to 1.5; the molar ratio of the prepared product to the hexamethylenetetramine is 1:1.2 to 1.7.

[0014] Preferably, the preparation method of compound b includes the following steps: adding 2-nitrobenzaldehyde, pentaerythritol and p-TsOH together into a toluene solution, heating and refluxing to obtain o-nitrophenyloxaspirocyclic ring, and then reducing it by heating and refluxing in methanol with hydrazine hydrate and Pd / C to prepare o-aminophenyloxaspirocyclic ring;

[0015] In the preparation of compound b, the molar ratio of 2-nitrobenzaldehyde, pentaerythritol and p-TsOH is 2:0.8-1.2:0.01-0.08.

[0016] Preferably, the molar ratio of compound a to compound b is 2:0.9 to 1.3.

[0017] Furthermore, in the preparation of compound SDCS, the reaction vessel needs to be connected to a water separator. The water separator is filled with dry molecular sieves to remove the water generated during the reaction, and finally an orange-yellow solid, namely compound SDCS, is obtained.

[0018] The compound SDCS prepared in this invention exhibits strong fluorescence emission at 584 nm. In a mixed solution of acetonitrile and water, the fluorescence intensity increases with increasing water content, demonstrating good AIEE properties. The emission intensity reaches its highest value when the water content is 90%, where water is a poor solvent and acetonitrile is a good solvent. The AIEE properties are shown in the attached figure. Figure 5 As shown.

[0019] This invention provides the time-dependent color-changing characteristics of the compound SDCS. When a solution of SDCS with a water content of 60% is prepared and left for 24 hours, the fluorescence of the solution changes from orange to green compared to the solution just prepared. The color-changing rate is negatively correlated with the water content, that is, the higher the water content, the slower the color-changing rate.

[0020] Secondly, this disclosure provides an application of a cyanostyrene derivative, which is used in information encryption and erasure, including the following steps:

[0021] Step 1: Prepare solutions of the compound SDCS with water contents of 50-60% and 62-67% respectively, with a concentration of 10 μM;

[0022] Step 2: Encrypt the two solutions with binary code information in a multi-well plate, and record and analyze the data at 0h, 6h, and 10h respectively;

[0023] Step 3: All sample spots show orange fluorescence at 0h; after 6h, some sample spots show green fluorescence, at which point the binary information can be read; after 10h, all sample spots turn green fluorescence, and the information is erased.

[0024] Furthermore, in step 1, the SDCS solution is a freshly prepared solution with a water content of 60% and 65%.

[0025] Furthermore, in step 2, the three types of information are "Blank code I", "CZU", and "Blank code II".

[0026] Preferably, the material after information encryption and erasure is recycled by evaporation, and the material after information encryption and erasure is restored to its original state by adding CH3CN / H2O mixed solvent.

[0027] Preferably, the two fluorescent colors of the SDCS are fixed using a solid matrix, and the prepared fluorescent powder is applied in dual-color latent fingerprint imaging, comprising the following steps:

[0028] S1: Prepare the compound SDCS into a solution with a water content of 60% and a concentration of 20 μM, and then let it stand for 24 h;

[0029] S2: The freshly prepared SDCS solution and the SDCS solution after standing for 24 hours are concentrated and dried to produce powders with different fluorescence emissions;

[0030] S3: Sprinkle the powder onto the latent fingerprint;

[0031] S4: Record and analyze fingerprint images.

[0032] Furthermore, in step S1, the SDCS solutions are the freshly prepared solution and the SDCS solution after being left for 24 hours, both of which have a water content of 60%.

[0033] Furthermore, in step S4, the software used to analyze the fingerprint image is ImageJ.

[0034] In summary, this application has the following beneficial effects:

[0035] 1. The compounds synthesized in this application have simple synthesis methods, inexpensive and readily available raw materials, and low molecular preparation costs;

[0036] 2. The SDCS molecule synthesized in this application has a time-dependent fluorescence color change characteristic in the CH3CN / H2O system. The fluorescence color changes from orange to green over time. In addition, its color change rate is negatively correlated with the water content, that is, the higher the water content, the slower the color change rate. This characteristic can be applied to time-dependent information encryption and erasure, which greatly improves the security level of data storage.

[0037] 3. The dynamic fluorescence properties of the SDCS in this application can be maintained in a solid matrix, thus enabling two stable fluorescence emissions of a single component. Utilizing this property, dual-color fluorescence imaging of latent fingerprints can be achieved, thereby obtaining more fingerprint information.

[0038] 4. The time-dependent color-changing supramolecular fluorescent material prepared in this application is of great significance for the future development of multi-channel applications of single-component organic light-emitting materials.

[0039] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit the scope of protection of this disclosure. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the technical solution of this application;

[0041] Figure 2 This is the 1H NMR spectrum of the compound SDCS in this application;

[0042] Figure 3 This is the carbon NMR spectrum of the compound SDCS in this application;

[0043] Figure 4 This is the high-resolution mass spectrum of the compound SDCS;

[0044] Figure 5 This is the fluorescence spectrum of the AIEE effect of the compound SDCS in this application;

[0045] Figure 6 This is the fluorescence spectrum of the time-dependent color change characteristics of the compound SDCS in this application;

[0046] Figure 7 These are fluorescence images of the time-dependent color change characteristics of the compound SDCS under different water contents in this application;

[0047] Figure 8 This application describes the use of the compound SDCS in information encryption and erasure.

[0048] Figure 9 This application describes the use of the compound SDCS in dual-color fingerprint imaging. Detailed Implementation

[0049] The following detailed description of this application is provided in conjunction with the embodiments. It should be noted that: unless otherwise specified, the conditions in the following embodiments are performed under conventional conditions or conditions recommended by the manufacturer. Unless otherwise specified, the raw materials used in the following embodiments are all from commercially available sources.

[0050] Example

[0051] Example 1

[0052] Preparation of compound SDCS:

[0053] Under a nitrogen atmosphere, compound a (0.26 g, 0.75 mmol) and compound b (0.38 g, 1.5 mmol) were added to a 100 mL three-necked flask and dissolved in 20 mL of EtOH. The mixture was stirred at room temperature for 24 h. After the reaction was complete, the mixture was filtered, and the filter cake was dissolved with DCM, rotary evaporated, and dried under vacuum to obtain an orange solid SDCS (0.44 g, 74%).

[0054] The 1H NMR spectrum of compound SDCS is attached. Figure 2 As shown: 1H NMR (300MHz, DMSO-d6, 298K): δ (ppm) = 13.46 (s, 2H, -OH), 9.05 (s, 2H, -CH = N), 8.11 (s, 2H, -CH = C), 7.9 8-7.87(m,8H,Ar-H),7.67-7.65(d,J=7.5Hz,2H,Ar-H),7.54-7.46(m,10H,Ar-H),7.39-7.34(m,2H,Ar -H),7.17-7.14(d,J=8.7Hz,2H,Ar-H),5.80(s,2H,-CH),4.62-4.58(d,J=11.4Hz,2H,-CH2-),3.99-3. 95(d,J=11.4Hz,2H,-CH2-), 3.89-3.86(d,J=11.1Hz,2H,-CH2-), 3.73-3.70(d,J=11.7Hz,2H,-CH2-).

[0055] The carbon NMR spectrum of compound SDCS is attached. Figure 3 As shown: 13 C NMR (101MHz, DMSO-d6, 298K): δ (ppm) = 162.92, 161.36, 145.44, 140.91, 133.85, 131.65, 130.43, 130.34, 130.13, 130 .07,128.96,128.91,126.90,126.38,124.89,119.63,118.23,117.87,117.85,109.57,98.24,70.26,69.57,32.02.

[0056] High-resolution mass spectra of compound SDCS, such as Figure 4 As shown: HRMS(ESI)m / z:[SDCS+H] + calcd for[C 51 H 41 N4O6] + =805.3021; ​​found 805.3007.

[0057] Based on the above experimental characterization, the structure of compound SDCS was determined to be:

[0058]

[0059] Example 2

[0060] AIEE properties of compound SDCS:

[0061] An aqueous solution of compound SDCS was prepared at a test concentration of 10 μM, using acetonitrile as a good solvent and water as a poor solvent. The fluorescence intensity in the figure gradually increases with increasing water content, as shown in the attached diagram. Figure 5 As shown.

[0062] Example 3

[0063] Time-dependent color-changing properties of compound SDCS:

[0064] A 10 μM solution of SDCS compound with a water content of 60% was prepared. After standing for 24 hours, the fluorescence of this solution showed a blue shift compared to the freshly prepared solution, with the fluorescence color changing from orange to green, as shown in the attached figure. Figure 6 As shown; furthermore, its color change rate is negatively correlated with water content, that is, the higher the water content, the slower the color change rate, as shown in the attached figure. Figure 7 As shown.

[0065] Example 4

[0066] Applications of the compound SDCS in dynamic information encryption and erasure:

[0067] Step 1: Weigh 1.6 mg of compound SDCS into a 10 mL volumetric flask, add deionized water to make up to 10 mL, and prepare a 0.2 mM stock solution;

[0068] Step 2: Transfer 200 μL of the mother liquor of compound SDCS into a 4 mL centrifuge tube using a pipette, add 1400 μL of acetonitrile and 2400 μL of water in sequence, and sonicate for 3 min to form aqueous phase dispersed nanoparticles with a water content of 60%.

[0069] Step 3: Transfer 200 μL of the mother liquor of compound SDCS into a 4 mL centrifuge tube using a pipette, add 1200 μL of acetonitrile and 2600 μL of water in sequence, and sonicate for 3 min to form aqueously dispersed nanoparticles with a water content of 65%.

[0070] Step 4: The two water content SDCS solutions prepared above are binary encoded in a multi-well plate, and fluorescence images are recorded at 0h, 6h, and 10h under a 365nm UV lamp. At 0h, "Blank code I" is displayed; at 6h, the binary code "CZU" is displayed; and at 10h, "Blank code II" is displayed. Information encryption and erasure are achieved, as shown in the attached diagram. Figure 8 As shown. In this embodiment, the ultrasonic instrument used is a commonly used laboratory ultrasonic cleaner with a frequency of 40kHz.

[0071] Example 5

[0072] Application of compound SDCS in latent fingerprint imaging:

[0073] Step 1: Transfer 400 μL of the mother liquor of the above compound SDCS to a 4 mL centrifuge tube using a pipette, add 1200 μL of acetonitrile and 2400 μL of water in sequence, and sonicate for 3 min to form aqueous phase dispersed nanoparticles. Prepare a total of 20 mL of fresh solution and SDCS solution after standing for 24 h.

[0074] Step 2: Concentrate both 20 mL SDCS solutions to 5 mL, with SDCS concentration at 20 μM and water content at 60%. Then, add 1 g of thoroughly ground montmorillonite to the 5 mL concentrate and remove the solvent under vacuum. Vacuum dry the resulting solid powder for 4 hours and store it in a desiccator for later use. All materials used for fingerprint deposition are also vacuum dried for 4 hours and then stored in a desiccator.

[0075] Volunteers touched their foreheads with their fingers and then gently touched the glass substrate, leaving latent fingerprints that were barely visible to the naked eye. Fluorescent fingerprint powder was then evenly sprinkled onto the latent fingerprints, and excess powder was gently blown away with a bulb syringe. The fingerprints were then placed under a 365nm ultraviolet lamp, producing very clear images. The fingerprint photographs were recorded. Both fluorescent fingerprint powders demonstrated high-resolution imaging, clearly generating primary, secondary, and tertiary fingerprint information, as shown in the attached image. Figure 9 As shown.

[0076] The above description is merely an exemplary embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A cyanostyrene derivative, characterized in that, The derivative is a compound SDCS; the structure of the compound SDCS is shown in formula (I):

2. The method for preparing a cyano-styrene derivative according to claim 1, characterized in that, The compound SDCS is prepared by dehydration condensation of compound a and compound b, and the reaction equation is as follows:

3. The method for preparing a cyanostyrene derivative according to claim 2, characterized in that, The preparation method of compound a includes the following steps: reacting p-hydroxyphenylacetonitrile and benzaldehyde at room temperature under NaOH / EtOH alkaline conditions to obtain the intermediate product 2-(4-hydroxyphenyl)-3-phenylacrylonitrile, then adding hexamethylenetetramine, using TFA / AcOH as solvent, and heating under reflux under nitrogen protection to prepare the compound a. In the preparation of compound a, the molar ratio of p-hydroxyphenylacetonitrile, sodium hydroxide, and benzaldehyde is 1:2 to 2.5:1 to 1.5; the molar ratio of the prepared product to the hexamethylenetetramine is 1:1.2 to 1.

7.

4. The method for preparing a cyanostyrene derivative according to claim 2, characterized in that, The preparation method of compound b includes the following steps: 2-nitrobenzaldehyde, pentaerythritol and p-TsOH are added to toluene solution and heated under reflux to obtain o-nitrophenyloxaspirocyclic ring, which is then reduced by heating under reflux in methanol with hydrazine hydrate and Pd / C to prepare o-aminophenyloxaspirocyclic ring; In the preparation of compound b, the molar ratio of 2-nitrobenzaldehyde, pentaerythritol and p-TsOH is 2:0.8-1.2:0.01-0.

08.

5. The method for preparing a cyanostyrene derivative according to claim 2, characterized in that, The molar ratio of compound a to compound b is 2:0.9 to 1.

3.

6. The application of the cyanostyrene derivative according to claim 1 or the cyanostyrene derivative prepared by any one of claims 2-5, characterized in that, The cyanostyrene derivative is used in information encryption and erasure, including the following steps: Step 1: Prepare solutions of the compound SDCS with water contents of 50-60% and 62-67% respectively, with a concentration of 10 μM; Step 2: Encrypt the two solutions with binary code information in a multi-well plate, and record and analyze the data at 0h, 6h, and 10h respectively; Step 3: All sample spots show orange fluorescence at 0h; after 6h, some sample spots show green fluorescence, at which point the binary information can be read; after 10h, all sample spots turn green fluorescence, and the information is erased.

7. The application of the cyanostyrene derivative according to claim 6, characterized in that, The material after information encryption and erasure is recycled through evaporation, and the material after information encryption and erasure is restored to its original state by adding CH3CN / H2O mixed solvent.

8. The application of the cyanostyrene derivative according to claim 7, characterized in that, The two fluorescent colors of the SDCS are fixed using a solid matrix, and the prepared fluorescent powder is applied to dual-color latent fingerprint imaging, comprising the following steps: S1: Prepare the compound SDCS into a solution with a water content of 60% and a concentration of 20 μM, and then let it stand for 24 h; S2: The freshly prepared SDCS solution and the SDCS solution after standing for 24 hours are concentrated and dried to produce powders with different fluorescence emissions; S3: Sprinkle the powder onto the latent fingerprint; S4: Record and analyze fingerprint images.

Images