Benzene 1, 8-naphthalene imide derivative and application thereof in phosphorescent information encryption

Abstract

A preparation method of the acene 1, 8-naphthalimide derivative comprises the steps that acene 1, 8-naphthalimide is added into a dichloromethane solvent, p-bromobenzoic acid, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and 4-dimethylaminopyridine are sequentially added, stirring is carried out, and the acene 1, 8-naphthalimide derivative is obtained. Fully stirring and reacting the reaction mixture at 40-50 DEG C for 10-12 hours to obtain a reaction solution 2; and carrying out ice water quenching, suction filtration, extraction, drying and rotary evaporation on the reaction liquid 2 to obtain a solid product, and carrying out column chromatography purification to obtain the compound acene 1, 8-naphthalimide derivative. The preparation method of the phosphorescent material is simple and convenient, compared with a noble metal phosphorescent system, the cost is low, the synthesis method of the guest phosphorescent dye is simple, the yield is high, the phosphorescent effect is obvious, and the phosphorescent phenomenon is stable, so that the application potential in the fields of phosphorescent anti-counterfeiting and the like is huge.

Description

Technical Field

[0001] The present invention relates to the technical field of phosphorescent materials, in particular to an organic phosphorescent material and a preparation method thereof, as well as applications in the field of phosphorescent anti-counterfeiting. Background Art

[0002] In organic phosphorescence, the luminescence of compounds is significantly reduced by molecular self-oscillation and spin, and is also quenched by the presence of oxygen. Therefore, host-guest doping has become a major approach to producing organic phosphorescent materials. The host in the host-guest doping can be small organic molecules (such as phthalamide) or polymers (such as polymethyl methacrylate and polyvinyl alcohol). Organic room-temperature phosphorescent materials are showing increasingly broad application prospects in fields such as chemical sensing, bioimaging, and anti-counterfeiting.

[0003] Early phosphorescent materials primarily achieved phosphorescence through the doping of precious metals. This was associated with high costs, complex production methods, high toxicity, and environmental non-compliance, significantly limiting their application. Therefore, it is imperative to develop phosphorescent materials that are simple to synthesize, have low toxicity, are economical and environmentally friendly, and have good adaptability. Summary of the Invention

[0004] The present invention aims to overcome the above technical difficulties by providing a 1,8-naphthoacene lactimide derivative and its application in phosphorescent information encryption. When doped with a host compound, the dye can produce an orange phosphorescent afterglow of up to 2.2 seconds. Furthermore, the phosphorescent material is readily available and has low manufacturing costs, showing great potential in areas such as phosphorescent anti-counterfeiting. The specific technical solution is as follows:

[0005] A 1,8-naphtholactam derivative, the structural formula of the derivative is

[0006]

[0007] The preparation method of the 1,8-naphtholactam derivative comprises the following steps:

[0008] (1) Add o-bromobenzaldehyde, 2-indolone, and potassium hydroxide to dimethyl sulfoxide solvent at room temperature, heat the reaction mixture to 120-140°C, and stir well under nitrogen for 2-4 hours to obtain reaction solution 1;

[0009] (2) extracting the reaction solution 1 in step (1), drying it, and rotary evaporating it to obtain a solid product;

[0010] (3) purifying the solid product in step (2) by column chromatography to obtain 1,8-naphtholactamone;

[0011] (4) adding the 1,8-naphthoacene lactimide in step (3) to a dichloromethane solvent, and sequentially adding p-bromobenzoic acid, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, and 4-dimethylaminopyridine, and stirring the reaction mixture at 40-50° C. for 10-12 h to obtain a reaction solution 2;

[0012] (5) quenching the reaction solution 2 in step (4) with ice water, filtering, extracting, drying, and rotary evaporation to obtain a solid product;

[0013] (6) Purify the solid product in step (5) by column chromatography to obtain compound DB-Br.

[0014] In the step (1), the molar ratio of o-bromobenzaldehyde, 2-indolone and potassium hydroxide (KOH) is 1:1.5-3:2-3.

[0015] In the step (4), the molar ratio of 1,8-naphthoacene lactimide, p-bromobenzoic acid, 4-dimethylaminopyridine (DMAP), and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCI) is 1:1.5-3:1.5-3:3-5.

[0016] In some preferred embodiments, the reaction temperature of step (1) is 120° C. and the reaction time is 4 hours, and the reaction temperature of step (4) is 50° C. and the reaction time is 12 hours.

[0017] The present invention also provides a use of the 1,8-naphtholactim derivative in fluorescent anti-counterfeiting materials.

[0018] The present invention also provides a phosphorescent anti-counterfeiting material, which comprises the 1,8-naphtholactimide derivative and polymethyl methacrylate, wherein the structural formula of the polymethyl methacrylate is The average molecular weight is about 10,000-15,000.

[0019] The mass ratio of the 1,8-naphtholactimide derivative to the polymethyl methacrylate is 1:100 to 5:100.

[0020] In some preferred embodiments, the mass ratio of 1,8-naphtholactimide derivative to polymethyl methacrylate is 1:100, 2:100, 3:100, 4:100, or 5:100.

[0021] The preparation method of the phosphorescent anti-counterfeiting material is to add 1,8-naphtholactimide derivative and polymethyl methacrylate into a solvent according to a mass ratio, mix them evenly under stirring conditions, transfer the mixture into a latex centroid-shaped groove mold, and volatilize the solvent at room temperature.

[0022] On the other hand, the phosphorescent anti-counterfeiting material is used in phosphorescent information encryption.

[0023] The beneficial effects of the present invention are as follows:

[0024] (1) The present invention introduces heavy atoms into the guest, resulting in a significant phosphorescent effect, stable phosphorescence, and reusability. (2) The present invention's p-bromobenzoylcyanocarbazole derivative, after being doped with the host compound, exhibits an orange phosphorescence afterglow time of up to 2.2 seconds. Compared to earlier phosphorescent materials, the present invention exhibits reduced toxicity, a simpler preparation method, lower material costs, and significantly reduced harm to the human body and the environment. It has great potential in areas such as phosphorescent anti-counterfeiting.

[0025] (3) The present invention is based on the luminescence mechanism of phosphorescent materials. It constructs a rigid structure within the molecule through 1,8-naphthocyanine, and introduces heavy atoms through p-bromobenzoic acid to cause electronic energy level crossing, thereby enhancing the spin-orbit coupling effect, thereby accelerating the intersystem crossing (ISC) rate from the singlet state (S1) to the triplet state (T1); at the same time, the rigid structure of polymethyl methacrylate outside the molecule is used to reduce the self-vibration and spin degree, and reduce the presence of oxygen in the doping system, thereby promoting its ISC effect and achieving a better room temperature phosphorescence afterglow effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is the DB-Br hydrogen spectrum of the compound obtained in Example 1.

[0027] Figure 2 This is the room temperature phosphorescence afterglow image of the guest compound DB-Br doped at a ratio of 1% in Example 3.

[0028] Figure 3 This is the room temperature phosphorescence afterglow image of the guest compound DB-Br doped at a ratio of 5% in Example 4. DETAILED DESCRIPTION

[0029] The present invention is further described below with reference to the following examples. However, the scope of protection claimed in the present invention is not limited to the scope described in the examples.

[0030] Example 1

[0031] Preparation of 1,8-naphthoacene lactimide:

[0032]

[0033] (1) At room temperature, o-bromobenzaldehyde (2.784 mL, 24 mmol), 2-indolone (4,788 g, 36 mmol), and potassium hydroxide (3.5 g, 62 mmol) were added to a reaction flask containing dimethyl sulfoxide (DMSO) solvent. The reaction mixture was stirred at 120°C under nitrogen for 4 h to obtain reaction solution 1.

[0034] (2) extracting the reaction solution 1 in step (1), drying it, and rotary evaporating it to obtain a solid product;

[0035] (3) Purifying the solid product in step (2) by column chromatography to obtain the compound 1,8-naphtholactam;

[0036] Example 2

[0037] Preparation of DB-Br:

[0038]

[0039] (1) To a reaction flask containing dichloromethane (DCM) at room temperature, 1,8-naphthoacene lactimide (1.1 g, 5 mmol), p-bromobenzoic acid (1.5 g, 7.5 mmol), N,N-dicyclohexylcarbodiimide (3.10 g, 15 mmol), and 1-hydroxybenzotriazole (1.49 g, 11 mmol) were added in sequence. The reaction mixture was stirred at 50°C for 12 h to obtain reaction solution 1.

[0040] (2) TLC detection of the solid product in step (1) revealed no target product;

[0041] Example 3

[0042] Preparation of DB-Br:

[0043]

[0044] (1) To a reaction flask containing dichloromethane (DCM) at room temperature, 1,8-naphthoacene lactimide (1.1 g, 5 mmol), p-bromobenzoic acid (1.5 g, 7.5 mmol), N,N-dicyclohexylcarbodiimide (DCC) (3.10 g, 15 mmol), and 4-dimethylaminopyridine (DMAP) (1.53 g, 11 mmol) were added in sequence. The reaction mixture was stirred at 50°C for 12 h to obtain reaction solution 1.

[0045] (2) TLC detection of the solid product in step (1) revealed no target product;

[0046] Example 4

[0047] Preparation of DB-Br:

[0048]

[0049] (1) To a reaction flask containing dichloromethane (DCM) at room temperature, 1,8-naphthoacene lactimide (1.1 g, 5 mmol), p-bromobenzoic acid (1.5 g, 7.5 mmol), 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCI) (2.87 g, 15 mmol), and 4-dimethylaminopyridine (1.53 g, 11 mmol) were added in sequence. The reaction mixture was stirred at 50°C for 12 h to obtain reaction solution 1.

[0050] (2) quenching the reaction solution 1 in step (1) with ice water, filtering, extracting, drying, and rotary evaporation to obtain a solid product;

[0051] (3) Purifying the solid product in step (2) by column chromatography to obtain the guest compound DB-Br;

[0052] Example 5

[0053] Preparation of DB-Br:

[0054]

[0055] (1) To a reaction flask containing dichloromethane (DCM) at room temperature, 1,8-naphthoacene lactimide (1.1 g, 5 mmol), p-bromobenzoic acid (1.5 g, 7.5 mmol), N,N-dicyclohexylcarbodiimide (DCC) (3.10 g, 15 mmol), and 4-dimethylaminopyridine (DMAP) (1.53 g, 11 mmol) were added in sequence. The reaction mixture was stirred at 50°C for 12 h to obtain reaction solution 1.

[0056] (2) TLC detection of the solid product in step (1) revealed no target product;

[0057] Table 1 Effect of different catalysts on reaction results in Examples 2 to 5

[0058] Catalyst 1 Catalyst 2 Target compound Example 2 DCC HOBT Unable to obtain Example 3 DCC DMAP Unable to obtain Example 4 EDCI DMAP available Example 5 EDCI HOBT Unable to obtain

[0059] As can be seen from Table 1, the target guest compound DB-Br can be obtained by using the EDCI and DMAP catalytic reaction of Example 2.

[0060] Example 6

[0061] The prepared powdered guest compound DB-Br exhibited blue fluorescence under 365nm UV light. After irradiating the doped solid with 365nm UV light for 5 seconds, the guest compound DB-Br showed no visible room temperature phosphorescence afterglow.

[0062] Example 7

[0063] The purchased host compound polymethyl methacrylate (PMMA) showed no fluorescence under 365nm UV light. When the doped solid was irradiated with 365nm UV light for 5 seconds, the pure compound showed no obvious room temperature phosphorescence afterglow at room temperature.

[0064] Example 8

[0065] The prepared guest compound DB-Br and the host compound (PMMA) were thoroughly stirred in chloroform at a mass ratio of 1:100 (i.e., the mass ratio of the guest compound was 1%). The mixture was transferred to a specific membrane mold and the solvent was evaporated at room temperature. After that, it was irradiated with a 365nm ultraviolet lamp to show orange fluorescence (see Figure 2 When the doped model is irradiated with 365nm UV light for 10s, the doped solid has an obvious orange room temperature phosphorescence afterglow phenomenon at room temperature (see Figure 2 (Figure 0.1s, 1s, 1.5s, and 1.8s in the figure), the time is about 1.8s.

[0066] Example 9

[0067] The prepared guest compound DB-Br and the host compound (PMMA) were thoroughly stirred in chloroform at a mass ratio of 5:100 (i.e., the mass ratio of the guest compound was 5%). The mixture was transferred to a specific membrane mold and the solvent was evaporated at room temperature. After that, it was irradiated with a 365nm ultraviolet lamp to show orange fluorescence (see Figure 2 When the doped model is irradiated with 365nm UV light for 10s, the doped solid has an obvious orange room temperature phosphorescence afterglow phenomenon at room temperature (see Figure 3 (Figure 0.1s, 1s, 1.5s, 2s, 2.2s in the figure), the time is about 2.2s.

[0068] When the amount of the guest compound DB-Br is increased by 4 times compared with Example 3, the intensity of the phosphorescence afterglow is greatly increased.

Claims

1. A 1,8-naphtholactam derivative, characterized in that: The structural formula of the derivative is 2. The method for preparing 1,8-naphtholactam derivatives according to claim 1, characterized in that: The steps include: (1) Add o-bromobenzaldehyde, 2-indolone, and potassium hydroxide to dimethyl sulfoxide solvent at room temperature, heat the reaction mixture to 120-140°C, and stir well under nitrogen for 2-4 hours to obtain reaction solution 1; (2) extracting the reaction solution 1 in step (1), drying it, and rotary evaporating it to obtain a solid product; (3) purifying the solid product in step (2) by column chromatography to obtain 1,8-naphtholactamone; (4) adding the 1,8-naphthoacene lactimide in step (3) to a dichloromethane solvent, and sequentially adding p-bromobenzoic acid, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, and 4-dimethylaminopyridine, and stirring the reaction mixture at 40-50° C. for 10-12 h to obtain a reaction solution 2; (5) quenching the reaction solution 2 in step (4) with ice water, filtering, extracting, drying, and rotary evaporation to obtain a solid product; (6) The solid product in step (5) is purified by column chromatography to obtain compound DB-Br, i.e.

3. The preparation method according to claim 2, characterized in that In the step (1), the molar ratio of o-bromobenzaldehyde, 2-indolone and potassium hydroxide (KOH) is 1:1.5-3:2-3.

4. The preparation method according to claim 2, characterized in that In the step (4), the molar ratio of 1,8-naphthoacene lactimide, p-bromobenzoic acid, 4-dimethylaminopyridine (DMAP), and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCI) is 1:1.5-3:1.5-3:3-5.

5. The preparation method according to claim 2, characterized in that The reaction temperature of step (1) is 120° C. and the reaction time is 4 hours. The reaction temperature of step (4) is 50° C. and the reaction time is 12 hours.

6. Use of the 1,8-naphtholactimide derivative according to claim 1 in fluorescent anti-counterfeiting materials.

7. A phosphorescent anti-counterfeiting material, characterized in that: The phosphorescent anti-counterfeiting material comprises the 1,8-naphtholactimide derivative according to claim 1 and polymethyl methacrylate, the structural formula of which is The average molecular weight is about 10,000-15,000.

8. The phosphorescent anti-counterfeiting material according to claim 7, characterized in that: The mass ratio of the 1,8-naphtholactimide derivative to the polymethyl methacrylate is 1:100 to 5:

100.

9. The phosphorescent anti-counterfeiting material according to claim 8, characterized in that: The mass ratios of 1,8-naphtholactam derivative and polymethyl methacrylate are 1:100, 2:100, 3:100, 4:100 and 5:

100.

10. Use of the phosphorescent anti-counterfeiting material according to any one of claims 7 to 9 in phosphorescent information encryption.

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