Pyrene derivatives, their preparation methods and applications

Abstract

This invention belongs to the field of heterocyclic compound technology, specifically relating to a pyrene derivative and its preparation method and application. The preparation method of the pyrene derivative includes the following steps: (1) adding 10-(6-bromopyrene-1-yl)-10H-phenthiazide, tetra(triphenylphosphine)palladium and potassium carbonate aqueous solution to an organic solution containing 4-(diphenylamino)phenylboronic acid and stirring to carry out a condensation reaction to obtain a pyrene derivative solution; (2) diluting the pyrene derivative solution and washing it, separating the phases to obtain an organic phase and an aqueous phase, extracting the organic phase from the aqueous phase, combining the organic phases and drying them to obtain an organic phase containing the pyrene derivative; (3) pre-distilling, chromatography and rotary evaporation of the organic phase containing the pyrene derivative to obtain the pyrene derivative. This invention changes the electron cloud arrangement in the pyrene derivative by introducing different groups into the asymmetric structure of the pyrene derivative, thereby changing the fluorescence properties, which has important applications in fingerprint fluorescence imaging.

Description

Technical Field

[0001] This invention belongs to the field of heterocyclic compound technology, specifically relating to a pyrene derivative, its preparation method, and its application. Background Technology

[0002] Fingerprints, as microscopic topological imprints left when an individual comes into contact with an object's surface, contain highly specific identity information. Latent fingerprints refer to the invisible patterns left when a finger touches an object's surface, usually formed by secretions such as sweat and sebum. The direction of fingerprint ridges, bifurcation angles, and the distribution patterns of detail features are recognized in forensic medicine as reliable evidence of individual identification and have significant judicial value. With the development of functional materials science, improving the accuracy and on-site applicability of fingerprint identification has become an important direction for fingerprint development. It is necessary to develop development techniques that combine high sensitivity, high selectivity, and good practicality. Existing fingerprint development methods often face problems such as insufficient contrast, loss of detail, and severe background interference when processing non-permeable surfaces or complex texture substrates, especially with limited ability to identify low-quality, trace residual fingerprints.

[0003] Aggregation-induced fluorescence technology can form high-resolution fingerprint patterns within 30 seconds and has advantages such as being non-toxic and applicable to multiple scenarios. Although fluorescent probes have made some progress in improving sensitivity, most materials have defects such as low quantum efficiency, poor environmental stability, or complex synthesis processes and high costs, which limit their application.

[0004] Pyrene derivatives are compounds formed by chemical modification of pyrene molecules. They possess unique optical and electronic properties and material application value, making their application in fingerprint development significant. Currently, commonly used methods for synthesizing pyrene derivatives focus on 1,3-asymmetric synthesis, 2,7-asymmetric synthesis, and 1,3 and 6,8-asymmetric synthesis. 1,6-asymmetric synthesis has been rarely studied in the preparation of pyrene derivatives because the two active sites (1 and 6) have identical activity, and it is difficult to synthesize them by introducing different substituents at each site.

[0005] Chinese patent CN113214277A discloses a pyrene-thiophene derivative and its preparation method. A pyrene-thiophene derivative is provided, the structure of which is shown in formula (I).

[0006]

[0007] The patent also provides a method for preparing a pyrene thiophene derivative, comprising: reacting 4-bromo-7-(pyridin-1-yl)benzo[c][1,2,5]thiadiazole with the compound shown in formula (II) via a substitution reaction to obtain the compound shown in formula (I).

[0008]

[0009] The compound in this patent has a maximum solid luminescence efficiency of 26.3%, which is poor and unstable when applied to fingerprint development.

[0010] Chinese patent CN118961665A discloses the application of an asymmetric pyrene derivative in fingerprint extraction. This asymmetric substituted pyrene derivative, used as a fluorescent probe, can capture stained fingerprints on smooth or rough surfaces using a high-definition camera under ultraviolet light excitation and generate high-resolution images. However, the pyrene derivative prepared in this patent has poor fluorescence efficiency.

[0011] Chinese patent CN120097867A discloses the application of a mechanochromic pyrene derivative in latent fingerprint fluorescence imaging and extraction. This mechanochromic pyrene derivative, through its unique fluorescence response characteristics, can selectively bind to fingerprint residue under ultraviolet light excitation, enabling latent fingerprints to form high-contrast fluorescence images on smooth or rough surfaces (such as glass, metal, and plastic), and is compatible with conventional camera equipment for rapid acquisition. The pyrene derivative prepared in this patent has relatively low fluorescence intensity. Summary of the Invention

[0012] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a pyrene derivative, which can improve the luminescence efficiency by using different groups to replace the 1 and 6 positions to prepare an asymmetric structure; the present invention also provides its preparation method and application.

[0013] The technical solution adopted by this invention to solve its technical problem is:

[0014] The pyrene derivative of this invention has the following structural formula:

[0015] .

[0016] in:

[0017] The method for preparing the pyrene derivative includes the following steps:

[0018] (1) Under a nitrogen atmosphere, 10-(6-bromopyrene-1-yl)-10H-phenthiazide, tetra(triphenylphosphine)palladium and potassium carbonate aqueous solution were added to an organic solution containing 4-(diphenylamino)phenylboronic acid and stirred to carry out a condensation reaction to obtain a pyrene derivative solution; wherein, the organic solution containing 4-(diphenylamino)phenylboronic acid was obtained by mixing 4-(diphenylamino)phenylboronic acid and an organic solvent;

[0019] (2) After diluting the pyrene derivative solution, wash it and separate the phases to obtain an organic phase and an aqueous phase. Extract the organic phase from the aqueous phase, combine the organic phases and dry them to obtain an organic phase containing the pyrene derivative.

[0020] (3) The organic phase containing pyrene derivatives was initially distilled, chromatographically analyzed and then rotary evaporated to obtain pyrene derivatives.

[0021] In step (1), the molar ratio of 4-(diphenylamino)phenylboronic acid, 10-(6-bromopyrene-1-yl)-10H-phenthiazine and tetra(triphenylphosphine)palladium is 40-50:20-25:1.

[0022] In step (1), the organic solvent is toluene or ethanol, the concentration of potassium carbonate aqueous solution is 1-3 mol / L, and the ratio of organic solvent, potassium carbonate aqueous solution and 4-(diphenylamino)phenylboronic acid is 65-75:18-27:1; the organic solvent and potassium carbonate aqueous solution are in mL, and 4-(diphenylamino)phenylboronic acid is in g.

[0023] In step (1), the stirring is reflux, the condensation reaction temperature is 100-110℃, and the condensation reaction time is 16-32h.

[0024] In step (2), dilution is performed using deionized water, with a volume ratio of deionized water to the organic solvent in step (1) of 1:4.4-6.3. Washing is performed using a saturated sodium chloride solution, with a volume ratio of saturated sodium chloride solution to the organic solvent in step (1) of 1:4.4-6.3. Extraction is performed using an extractant, which is toluene or ethanol, and the extraction is performed 1-2 times. Drying is performed using anhydrous magnesium sulfate.

[0025] In step (3), the preliminary distillation is vacuum distillation with a pressure of 1-2 kPa and a distillation time of 10-20 min. The chromatography is performed using dichloromethane and petroleum ether as eluents with a volume ratio of 1:3-5, a rotary evaporation temperature of 50-60℃, and a rotary evaporation time of 10-20 min.

[0026] The pyrene derivatives described herein are used in fingerprint extraction.

[0027] The process involves mixing and stirring a pyrene derivative with neutral alumina to produce fingerprint powder, then attaching the fingerprint powder to a carrier containing potential fingerprints, followed by irradiation with ultraviolet light and extraction.

[0028] The mass ratio of the pyrene derivative to neutral alumina is 1:45-55. The extraction method involves photographing and preserving fingerprints irradiated with ultraviolet light, with an ultraviolet wavelength of 365nm and an illumination angle of 30-45°.

[0029] The reaction equation for preparing pyrene derivatives according to this invention is as follows:

[0030]

[0031] This invention utilizes a one-pot mixed reaction of 4-(diphenylamino)phenylboronic acid, 10-(6-bromopyrene-1-yl)-10H-phenthiazine, and tetra(triphenylphosphine)palladium to achieve stepwise functionalization. Phenthiazine and triphenylamine groups are introduced onto the pyrene compound as electron-donating and electron-withdrawing groups, respectively. Both phenthiazine and triphenylamine groups, being stereochemical structures, act synergistically around the pyrene compound, further enhancing steric hindrance and forming a "steric barrier." This effectively prevents the molecules from forming tight π-π packing in the solid or aggregated state, resulting in a more uniform and stable pyrene derivative. The synergistic effect of the phenthiazine and triphenylamine groups on the pyrene derivative can influence the intensity of intramolecular charge transfer, thereby controlling the absorption and emission wavelengths of the material. This achieves coverage from blue light to red light and even near-infrared light, significantly improving the luminescence effect. During the reaction, potassium carbonate aqueous solution provides an alkaline environment to activate 4-(diphenylamino)phenylboronic acid, while tetra(triphenylphosphine)palladium acts as a catalyst to promote the reaction. The reaction of 10-(6-bromopyrene-1-yl)-10H-phenthiazide with the active group on 4-(diphenylamino)phenylboronic acid generates a target product with an asymmetric structure, achieving electronic interaction along the long axis of the pyrene nucleus. This allows for more efficient and significant regulation of the photophysical properties of pyrene derivatives, exhibiting a more pronounced regulatory effect compared to asymmetric structures along the short axis. This is of great significance for the synthesis of pyrene-based full-color luminescent materials. Due to the significant fluorescence effect of pyrene-based derivatives, no large amount needs to be added to the prepared fingerprint powder to achieve the development of latent fingerprints. Neutral alumina is chemically stable, and the pyrene derivatives are well dispersed within it. Therefore, a small amount of neutral alumina can highlight the luminescent effect of the pyrene-based derivatives. The fingerprint powder prepared at the mass ratio of pyrene-based derivatives to neutral alumina of 1:45-55, as set in this invention, can effectively extract fingerprints while controlling costs. After grinding, the obtained pyrene-based derivatives undergo mechanical discoloration under ultraviolet light irradiation, producing changes in fluorescence color and intensity.

[0032] The beneficial effects of this invention are:

[0033] This invention introduces different groups into the asymmetric structure of pyrene derivatives, thereby changing the electron cloud arrangement in the pyrene derivatives and thus achieving changes in fluorescence properties. The asymmetric mechanochromic pyrene derivatives expand the types of substances used in traditional fingerprint imaging and have important applications in fingerprint fluorescence imaging.

[0034] This invention uses 4-(diphenylamino)phenylboronic acid and 10-(6-bromopyrene-1-yl)-10H-phenthiazide as raw materials. The raw materials are inexpensive and readily available, the intermediates are simple to prepare and have stable properties, do not require special storage conditions, and have low cost. The prepared mechanochromic pyrene derivative provides a new substance for fingerprint extraction. The reaction conditions are relatively mild, the operation is simple, the overall synthetic route is simple, the yield is high, the pollution is low, and there is no need for complicated purification steps, making it easier to prepare and apply in industrial applications.

[0035] The mechanochromic pyrene derivative prepared in this invention not only exhibits reversible fluorescence response characteristics under mechanical stimulation, but also reacts efficiently with fingerprint lipid components under ultraviolet light excitation, significantly enhancing the fluorescence contrast and image clarity of ridge structures. Particularly noteworthy is the high fluorescence quantum yield of this pyrene derivative, which greatly improves the detection capability of weak fingerprint signals. It is suitable for latent fingerprint visualization on non-permeable and complex textured surfaces, significantly improving fingerprint imaging brightness. The solid-state luminescence efficiency of the pyrene derivative can reach over 56%.

[0036] Furthermore, the pyrene derivatives prepared in this invention possess excellent solid-state fluorescence efficiency and good surface adaptability, effectively highlighting secondary details of fingerprints, such as island structures and short ridges. Some tertiary microstructures, such as sweat pore distribution, can also be effectively highlighted, significantly overcoming the limitations of traditional methods in low-quality fingerprint identification. This technical approach not only provides a new functional material basis for rapid and high-fidelity visualization of trace evidence at the scene, but also significantly improves the efficiency and reliability of fingerprint identification, possessing important application value and promotion significance. Attached Figure Description

[0037] Figure 1 These are the fluorescence emission spectra of the pyrene derivatives prepared in Example 1 of this invention in different solvents;

[0038] Figure 2 This is the 1H NMR spectrum of the pyrene derivative prepared in Example 1 of this invention;

[0039] Figure 3 This is a fingerprint effect image extracted in Embodiment 1 of the present invention. Detailed Implementation

[0040] The present invention will be further described below with reference to embodiments.

[0041] Example 1

[0042] The preparation method of pyrene derivatives includes the following steps:

[0043] (1) Under a nitrogen atmosphere, 2.39 g of 10-(6-bromopyrene-1-yl)-10H-phenthiazide, 0.289 g of tetrakis(triphenylphosphine)palladium and 64 mL of 2 mol / L potassium carbonate aqueous solution were added to an organic solution containing 4-(diphenylamino)phenylboronic acid and stirred under reflux at 101 °C for 24 h to carry out a condensation reaction, thereby obtaining a pyrene derivative solution; the organic solution containing 4-(diphenylamino)phenylboronic acid was obtained by mixing 3.44 g of 4-(diphenylamino)phenylboronic acid and 250 mL of toluene;

[0044] (2) The pyrene derivative solution was diluted with 40 ml of deionized water and then washed with 40 ml of saturated sodium chloride solution to wash the impurities in the organic matter into the aqueous phase. The phases were separated to obtain an organic phase and an aqueous phase. The organic phase in the aqueous phase was then extracted with toluene twice. The organic phases were combined and dried with anhydrous magnesium sulfate to obtain an organic phase containing pyrene derivatives.

[0045] (3) The organic phase containing the pyrene derivative was subjected to vacuum distillation at 1 kPa for 15 min, followed by gradient elution chromatography using dichloromethane and petroleum ether at a volume ratio of 1:4. The pyrene derivative was then obtained by rotary evaporation at 55 °C for 15 min. The pyrene derivative was a yellow-green solid. The fluorescence emission spectra of the pyrene derivative in different solvents are shown below. Figure 1 As shown, the proton NMR spectrum is as follows: Figure 2 As shown, the luminous efficiency is 57.3%;

[0046] Application of pyrene derivatives in fingerprint extraction:

[0047] Fingerprint powder was prepared by mixing 1g of pyrene derivative and 50g of neutral alumina. The fingerprint powder was then applied to non-fluorescent paper containing potential fingerprints. The paper was subsequently irradiated with 365nm ultraviolet light and photographed at a 30° lighting angle. The resulting fingerprint image on the non-fluorescent paper is shown below. Figure 3 As shown.

[0048] Example 2

[0049] The preparation method of pyrene derivatives includes the following steps:

[0050] (1) Under a nitrogen atmosphere, 2.51 g of 10-(6-bromopyrene-1-yl)-10H-phenthiazide, 0.31 g of tetrakis(triphenylphosphine)palladium and 80 mL of 3 mol / L potassium carbonate aqueous solution were added to an organic solution containing 4-(diphenylamino)phenylboronic acid and stirred under reflux at 108 °C for 32 h to carry out a condensation reaction, thereby obtaining a pyrene derivative solution; the organic solution containing 4-(diphenylamino)phenylboronic acid was obtained by mixing 3.6 g of 4-(diphenylamino)phenylboronic acid and 235 mL of toluene;

[0051] (2) The pyrene derivative solution was diluted with 50 ml of deionized water and then washed with 50 ml of saturated sodium chloride solution to wash the impurities in the organic matter into the aqueous phase. The phases were separated to obtain the organic phase and the aqueous phase. The organic phase in the aqueous phase was then extracted with toluene twice. The organic phases were combined and dried with anhydrous magnesium sulfate to obtain the organic phase containing the pyrene derivative.

[0052] (3) The organic phase containing the pyrene derivative was subjected to vacuum distillation at 1 kPa for 20 min, and gradient elution chromatography was performed using dichloromethane and petroleum ether at a volume ratio of 1:3. After rotary evaporation at 50 °C for 20 min, the pyrene derivative was obtained. The pyrene derivative was a yellow-green solid with a luminescence efficiency of 56.8%.

[0053] Application of pyrene derivatives in fingerprint extraction:

[0054] Fingerprint powder was prepared by mixing 1g of pyrene derivative and 45g of neutral alumina. The fingerprint powder was then applied to non-fluorescent paper containing potential fingerprints, and the paper was then irradiated with ultraviolet light at a wavelength of 365nm and photographed at a 45° lighting angle.

[0055] Example 3

[0056] The preparation method of pyrene derivatives includes the following steps:

[0057] (1) Under a nitrogen atmosphere, 2.43 g of 10-(6-bromopyrene-1-yl)-10H-phenthiazide, 0.35 g of tetrakis(triphenylphosphine)palladium and 95 mL of 1 mol / L potassium carbonate aqueous solution were added to an organic solution containing 4-(diphenylamino)phenylboronic acid and stirred under reflux at 110 °C for 16 h to carry out a condensation reaction, thereby obtaining a pyrene derivative solution; the organic solution containing 4-(diphenylamino)phenylboronic acid was obtained by mixing 3.57 g of 4-(diphenylamino)phenylboronic acid and 265 mL of toluene;

[0058] (2) The pyrene derivative solution was diluted with 60 ml of deionized water and then washed with 60 ml of saturated sodium chloride solution to wash the impurities in the organic matter into the aqueous phase. The phases were separated to obtain the organic phase and the aqueous phase. The organic phase in the aqueous phase was then extracted with toluene three times. The organic phases were combined and dried with anhydrous magnesium sulfate to obtain the organic phase containing the pyrene derivative.

[0059] (3) The organic phase containing the pyrene derivative was subjected to vacuum distillation at 2 kPa for 10 min, and gradient elution chromatography was performed using dichloromethane and petroleum ether at a volume ratio of 1:5. After rotary evaporation at 60 °C for 10 min, the pyrene derivative was obtained. The pyrene derivative was a yellow-green solid with a luminescence efficiency of 57.1%.

[0060] Application of pyrene derivatives in fingerprint extraction:

[0061] Fingerprint powder was prepared by mixing 1g of pyrene derivative and 55g of neutral alumina. The fingerprint powder was then applied to non-fluorescent paper containing potential fingerprints, and the paper was then irradiated with ultraviolet light at a wavelength of 365nm and photographed at a 40° lighting angle.

[0062] Comparative Example 1

[0063] The pyrene derivative obtained by using the preparation steps of Example 1 in Chinese Patent CN118961665A has a solid-state luminescence efficiency of 21%.

[0064] Comparative Example 2

[0065] The mechanically color-changing pyrene derivative obtained by using the preparation steps of the synthesis of 4-pyrene-2-hydroxybenzaldehyde as an example in the embodiment of Chinese patent CN120097867A has a solid-state luminescence efficiency of 32%.

[0066] Comparative Example 3

[0067] In step (1), potassium carbonate aqueous solution is not used, and the remaining steps are as in Example 1; the fluorescence efficiency of the obtained pyrene derivative is 30.75%, and the fingerprint development effect is poor when fingerprint extraction is performed.

[0068] Comparative Examples 1 and 2 show that the asymmetric structure in the prior art has low fluorescence efficiency. Comparative Example 3 and Example 1 show that without the use of potassium carbonate aqueous solution, an alkaline environment cannot be provided to promote the reaction, resulting in a lower fluorescence efficiency of the obtained substance.

Claims

1. A pyrenyl derivative, characterized by, The structural formula is as follows: 。 2. A method of preparing the pyrene-based derivative of claim 1, characterized by, The method comprises the following steps: (1) under a nitrogen atmosphere, 10-(6-bromopyrene-1-yl)-10H-phenothiazine, tetrakis(triphenylphosphine)palladium and an aqueous potassium carbonate solution are added to an organic solution containing 4-(diphenylamino)phenyl boronic acid to perform a condensation reaction by stirring, to obtain a pyrene derivative solution; wherein the organic solution containing 4-(diphenylamino)phenyl boronic acid is obtained by mixing 4-(diphenylamino)phenyl boronic acid and an organic solvent; (2) the pyrene derivative solution is diluted, washed, separated into organic and aqueous phases, and the organic phase in the aqueous phase is extracted; the organic phases are combined and dried to obtain an organic phase containing the pyrene derivative; (3) the organic phase containing the pyrene derivative is subjected to preliminary distillation, chromatography and re-evaporation to obtain the pyrene derivative.

3. The method for preparing the pyrene derivative according to claim 2, characterized in that, In step (1), the molar ratio of 4-(diphenylamino)phenyl boronic acid, 10-(6-bromopyrene-1-yl)-10H-phenothiazine and tetrakis(triphenylphosphine)palladium is 40-50:20-25:

1.

4. Use of a pyrene derivative according to claim 2, characterized in that, In step (1), the organic solvent is toluene or ethanol, the concentration of the aqueous potassium carbonate solution is 1-3 mol / L, and the ratio of the organic solvent, the aqueous potassium carbonate solution and 4-(diphenylamino)phenyl boronic acid is 65-75:18-27:1; the organic solvent and the aqueous potassium carbonate solution are measured in mL, and 4-(diphenylamino)phenyl boronic acid is measured in g.

5. The method for preparing the pyrene derivative according to claim 2, characterized in that, In step (1), the stirring is reflux stirring, the condensation reaction temperature is 100-110 DEG C, and the condensation reaction time is 16-32 h.

6. The method for preparing the pyrene derivative according to claim 2, characterized in that, In step (2), the dilution is performed by dilution with deionized water, the volume ratio of deionized water to the organic solvent in step (1) is 1:4.4-6.3, the washing is performed by washing with a saturated sodium chloride solution, the volume ratio of the saturated sodium chloride solution to the organic solvent in step (1) is 1:4.4-6.3, the extraction is performed by extraction with an extraction agent, the extraction agent is toluene or ethanol, the extraction is performed 1-2 times, and the drying is performed by drying with anhydrous magnesium sulfate.

7. The method for preparing the pyrene derivative according to claim 2, characterized in that, In step (3), the preliminary distillation is performed by reduced pressure distillation, the preliminary distillation pressure is 1-2 kPa, the preliminary distillation time is 10-20 min, the chromatography is performed by using dichloromethane and petroleum ether as eluents, the volume ratio of dichloromethane to petroleum ether is 1:3-5, the rotary evaporation temperature is 50-60 DEG C, and the rotary evaporation time is 10-20 min.

8. Use of a pyrene derivative according to claim 1, characterized in that The pyrene derivative is applied to fingerprint extraction.

9. Use of a pyrene derivative according to claim 8, characterized in that, The pyrene derivative and neutral alumina are mixed and stirred to prepare fingerprint powder, the fingerprint powder is attached to a carrier containing latent fingerprints, and then the carrier is irradiated with ultraviolet light and extracted.

10. Use of a pyrene derivative according to claim 9, characterized in that, The mass ratio of the pyrene derivative to the neutral alumina is 1:45-55, and the extraction is performed by taking a photo of the fingerprints irradiated by the ultraviolet light.

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