Perylene diimide-TEMPO photosensitizer molecule as well as preparation method and application thereof

Abstract

The invention discloses a perylene diimide-TEMPO photosensitizer molecule as well as a preparation method and application thereof, and belongs to the technical field of functional materials. Based on a perylene diimide chromophore and a TEMPO free radical, a novel heavy-atom-free perylene diimide-TEMPO photosensitizer based on a free radical promotion intersystem crossing mechanism is designed and synthesized; compared with a traditional photosensitizer, the photosensitizer does not contain heavy atoms, has the advantages of being low in toxicity, simple in synthesis method, low in price and the like, can efficiently generate singlet oxygen and has long triplet service life. Besides, the triplet photosensitizer molecule can be used as a photoinitiator, has excellent free radical polymerization initiation performance under a xenon lamp, is good in photobleaching performance and can be applied to free radical photocuring of a deep system.

Description

Technical Field

[0001] The present invention belongs to the field of organic functional molecule synthesis, and in particular to a preparation method and application of a heavy atom-free perylene diimide-TEMPO photosensitizer that can efficiently generate singlet oxygen and has free radical photopolymerization ability. Background Art

[0002] Triplet photosensitizers are molecules that, upon photoexcitation, can transition from a singlet excited state to a triplet excited state through intersystem crossing. Triplet photosensitizers with long excited-state lifetimes and high excited-state energy levels can fully exploit their excited-state properties through electron transfer or energy transfer. They are widely used in photodynamic therapy, photocatalytic organic reactions, photopolymerization, organic photovoltaics, and photohydrogen production from water, playing a vital role in the development of biomedicine and energy utilization.

[0003] Because intersystem crossing from the singlet to triplet state is spin-forbidden, conventional triplet photosensitizers often leverage heavy atom effects to overcome this energy transition limitation. By introducing transition metals such as ruthenium, platinum, and iridium, or halogen atoms such as bromine and iodine, they promote intersystem crossing to achieve triplet excited states (e.g., the paper "In Vitro Demonstration of the Heavy-Atom Effect for Photodynamic Therapy," DOI: 10.1021 / ja047649e). Given the high cost and synthesis costs of these photosensitizers, as well as their potential for biotoxicity, the development of highly efficient, heavy-atom-free triplet photosensitizers is crucial.

[0004] 2,2,6,6-Tetramethylpiperidinyl oxide (TEMPO) is a type of free radical that can exist stably in air. When free radicals such as TEMPO are introduced into the chromophore, the electron spin-spin exchange interaction between the free radical and the chromophore can convert the spin-forbidden S1→T1 intersystem crossing process into a spin-allowed 2 (RS) → 2The chromophore undergoes a triplet-like (RT) conversion process, thereby promoting the generation of a triplet state (e.g., Radical-Enhanced Intersystem Crossing in New Bodipy Derivatives and Application for Efficient Triplet−Triplet Annihilation Upconversion, J. Am. Chem. Soc., 2017, 139, 7831−7842. DOI: 10.1021 / jacs.7b02063). Utilizing this mechanism of free radical-promoted intersystem crossing can overcome the drawbacks of traditional triplet photosensitizers, such as high cost, difficult synthesis, and high toxicity, and may serve as a new approach for designing heavy-atom-free triplet photosensitizers. To achieve optimal applications in photodynamic therapy and photopolymerization, a good triplet photosensitizer should exhibit efficient intersystem crossing, the ability to efficiently generate singlet oxygen, strong visible light absorption, and a long triplet lifetime. However, there are currently few types of triplet photosensitizers designed based on this mechanism, the triplet yield of the photosensitizers is low, and the lifetime is short, which limits their application in related fields.

[0005] Therefore, the development of heavy atom-free triplet photosensitizers with high singlet oxygen yield, strong visible light absorption ability, and long triplet lifetime based on the free radical-promoted intersystem crossing mechanism has become an issue that urgently needs to be studied and solved. Summary of the Invention

[0006] Perylene diimide (PBI) possesses a highly conjugated planar structure, exhibits strong absorption in the visible light region, is stable, and is easily derivatized, making it a class of dye molecules with unique photophysical properties. To address the shortcomings of current heavy-atom-free photosensitizers designed using free radical-promoted intersystem crossing mechanisms, this invention utilizes perylene diimide as a chromophore, linking it to TEMPO radicals at various sites and lengths to create a series of perylene diimide-TEMPO radical molecules. These molecules, based on free radical induction, promote efficient intersystem crossing of the chromophore, generating long-lived triplet excited states. The molecules contain no heavy atoms and can be used as a novel photosensitizer in visible-light-stimulated free radical photopolymerization.

[0007] The present invention provides a perylene diimide-TEMPO photosensitizer that can efficiently generate singlet oxygen and has photopolymerization ability. The general molecular structure formula is as follows:

[0008]

[0009] Among them, R1 is ; R2 is or ; m, n are integers of 8-10; X is hydrogen;

[0010] Alternatively, R1 and R2 are each independently selected from or ; m, n are integers of 8-10; the general formula contains at least one substituent X, X is or ; q1 and q2 are integers from 1 to 5.

[0011] Furthermore, R1 is ; R2 is , m and n are integers of 8-10; X is hydrogen.

[0012] Preferably, m is 10 and n is 8.

[0013] Furthermore, R1 and R2 are ; m, n are integers of 8-10; the general formula includes one or two substituents X, X is ; q1 and q2 are integers from 1 to 5.

[0014] Preferably, m is 10, n is 8, and q1 is 1.

[0015] Preferably, the compound structure is:

[0016] or or or or .

[0017] The second object of the present invention is to provide a method for preparing the triplet photosensitizer, comprising the following general synthetic steps:

[0018] S1: Under nitrogen protection, a mixture of raw materials PBI, different amino derivatives and imidazole was stirred at 160 ° C for 6 hours to obtain intermediates;

[0019] S2: Under nitrogen protection, The intermediate reacts with liquid bromine in chloroform solvent for 48 hours at room temperature to obtain a bilateral bromine-substituted intermediate. and unilateral bromine-substituted intermediates .

[0020] S3: Bilateral bromination of intermediates under nitrogen protection or unilateral bromine substituted intermediate With intermediates The dry 1,4-dioxane and methanol mixture were reacted at 100 °C for 36 hours to generate a bilaterally substituted product. or unilateral substitution products .

[0021] In the steps, A-X1 and A-X2 can be independently selected from any one of formula (2);

[0022] In the steps, BX can be independently selected from any one of formula (3)

[0023] The third object of the present invention is to provide the use of a perylene diimide-TEMPO free radical type heavy atom-free photosensitizer in photopolymerization.

[0024] Furthermore, the photopolymerizable composition includes a polymerizable monomer, a photosensitizer, and a photoinitiator;

[0025] The photosensitizer is the compound according to any one of claims 1 to 6, and the weight of the photosensitizer accounts for 0.06 wt% to 0.10 wt% of the weight of the photopolymerizable composition.

[0026] The photoinitiator further includes a second photoinitiator, or a second photoinitiator and an additive;

[0027] The second photoinitiator includes at least one of a benzophenone photoinitiator, an α-hydroxyketone photoinitiator, an α-aminoketone photoinitiator, a dimethylaminobenzophenone photoinitiator, a thioxanthone photoinitiator, a xanthone photoinitiator, a biimidazole photoinitiator, a triazine photoinitiator, and an acyl oxime photoinitiator;

[0028] The additives include at least one of a colorant, an alkali-soluble resin, an adhesion promoter, a surfactant, and a dispersant.

[0029] Compared with the prior art, the advantages of this patent application are:

[0030] 1. The photosensitizer designed and synthesized by this patent has a simple molecular structure, few synthetic steps, does not contain heavy atoms such as transition metals and halogens, and has low toxicity and good biocompatibility;

[0031] 2. The photosensitizer molecule described in the present invention is based on a perylene diimide chromophore and has strong light absorption in the visible light band. By changing the distance and connection position between the chromophore and the free radical, the intersystem crossing and triplet quantum yield are regulated, thereby increasing the singlet oxygen yield and extending the triplet lifetime.

[0032] 3. The present invention proposes a novel heavy-atom-free perylene diimide-TEMPO photosensitizer based on the perylene diimide chromophore and TEMPO free radical, which is designed and synthesized based on the free radical-promoted intersystem crossing mechanism. Compared with traditional photosensitizers, it has the advantages of low toxicity, simple synthesis method, low price, etc., and can efficiently generate singlet oxygen ( 1 O2), and has a long triplet lifetime;

[0033] 4. The photosensitizer molecules designed and synthesized in this patent can be used as photoinitiators and have high initiation efficiency under xenon lamps;

[0034] 5. The photosensitizer molecules designed and synthesized in this patent have good photobleaching performance and can be used for photocuring of deep systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Schematic diagram of the infrared spectrum of compound 5-1;

[0036] Figure 2 This is the MALDI-TOF high-resolution accurate mass calibration characterization diagram of compound 5-1.

[0037] Figure 3 Schematic diagram of the infrared spectrum of compound 6-1;

[0038] Figure 4 This is the MALDI-TOF high-resolution accurate mass calibration characterization diagram of compound 6-1.

[0039] Figure 5 This is a graph showing the change in DPBF absorption peak intensity versus irradiation time in the presence of compound 5-1.

[0040] Figure 6 This is a graph showing the change in DPBF absorption peak intensity versus irradiation time in the presence of compound 6-1.

[0041] Figure 7 is the UV-visible absorption spectrum of compound 5-1.

[0042] Figure 8 This is the nanosecond transient absorption spectrum of compound 5-1.

[0043] Figure 9 This is the triplet lifetime decay curve of compound 5-1.

[0044] Figure 10 is the UV-visible absorption spectrum of compound 6-1.

[0045] Figure 11 This is the nanosecond transient absorption spectrum of compound 6-1.

[0046] Figure 12This is the triplet lifetime decay curve of compound 6-1.

[0047] Figure 13 This is the photobleaching curve of compound 5-1.

[0048] Figure 14 This is the photobleaching curve of compound 6-1.

[0049] Figure 15 This is a diagram of monomer polymerization initiated by compound 5-1.

[0050] Figure 16 This is a diagram of monomer polymerization initiated by compound 6-1. DETAILED DESCRIPTION

[0051] The present invention will be further described below with reference to the examples, but the present invention is not limited to the following examples.

[0052] Example 1

[0053] The synthesis of triplet photosensitizer material formula (5-1) is carried out according to the following reaction equation:

[0054]

[0055] The synthesis of Intermediate I follows the following protocol: Under nitrogen, a mixture of 3,4,9,10-perylenetetracarboxylic dianhydride (4.0 g, 10.2 mmol), imidazole (20.0 g, 294 mmol), and 2-octyldodecylamine (7.6 mL, 42.0 mmol) was heated and stirred at 160 °C for 6 hours. After completion, the reaction was cooled to room temperature, brine (200 mL) was added, and the reaction mixture was extracted with dichloromethane. The organic layer was then dried over anhydrous sodium sulfate and concentrated by rotary evaporation. The crude product was purified by column chromatography using silica gel with a dichloromethane:n-hexane (volume ratio 2:3) as the eluent to afford Intermediate I (8.6 g, 90% yield) as a red solid.

[0056] The synthesis of Intermediate II follows: Under nitrogen, a mixture of Intermediate I (2.0 g, 3.3 mmol), liquid bromine (9.0 mL, 180.0 mmol), and chloroform (50 mL) was stirred at room temperature for 48 hours. After completion of the reaction, the organic layer was washed with a saturated aqueous sodium thiosulfate solution. Subsequently, the organic layer was dried over anhydrous sodium sulfate and concentrated to obtain an organic phase. The crude product was purified by column chromatography using silica gel with a dichloromethane:n-hexane (volume ratio 2:3) as the eluent to obtain Intermediate II (0.67 g, 31% yield) as a red solid.

[0057] The synthesis of Intermediate III was as follows: Tetraisopropyl titanate (3.07 g, 10.8 mmol) was added dropwise to 4-oxo-TEMPO (1.53 g, 9 mmol) and stirred for 20 minutes. N-tert-Butyloxycarbonyl-1,2-ethylenediamine (2.92 g, 18 mmol) was then added portionwise, and the reaction mixture was stirred for 3 hours. The mixture was diluted with 500 mL of methanol before sodium cyanoborohydride (0.57 g, 9 mmol) was added. The resulting solution was stirred for 24 hours. After the reaction, water was added to precipitate a white precipitate, which was filtered and washed with ethyl acetate. The combined organic layers were washed with brine. The organic layer was dried over anhydrous sodium sulfate and concentrated by distillation under reduced pressure. The crude product was purified by column chromatography using silica gel with ethyl acetate / triethylamine / n-hexane (volume ratio 7:0.1:3) as the eluent. Intermediate III was obtained as a white oil (0.88 g, 31% yield).

[0058] The synthesis of Intermediate IV follows the following protocol: To a solution of Intermediate III (0.88 g, 2.8 mmol) in dichloromethane, an excess of trifluoroacetic acid (0.32 g, 28 mmol) was added and the mixture was allowed to react at room temperature for 4 hours. Subsequently, the solvent was removed by distillation under reduced pressure. The resulting oil was soaked in a mixture of methanol and dichloromethane (1:400 by volume), and anhydrous potassium carbonate (2 g) was added and stirred overnight. After filtration through celite, the filtrate was collected and the solvent removed by distillation under reduced pressure. This afforded Intermediate IV as a white oil (0.55 g, 98% yield).

[0059] The synthesis of triplet photosensitizer material (5-1) was as follows: Under nitrogen, PBI-Br (102.9 mg, 0.1 mmol) was added to a dry 1,4-dioxane solution. A dry methanol solution containing TEMPO (214.3 mg, 1 mmol) was then added via syringe. The volume ratio of 1,4-dioxane to methanol was 1:1. The reaction mixture was incubated at 100 °C for 36 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with dichloromethane (3 × 15 mL). The combined organic phases were washed with brine (2 × 10 mL) and then dried over anhydrous sodium sulfate. After drying the organic phase over anhydrous sodium sulfate, the solvent was concentrated by distillation under reduced pressure. The crude product was purified by column chromatography using a silica gel column with a dichloromethane:n-hexane (volume ratio 2:3) as the eluent to obtain a blue solid (65.1 mg, 56% yield).

[0060] Example 2

[0061] The synthesis of triplet photosensitizer material formula (6-1) is carried out according to the following reaction equation:

[0062]

[0063] The synthesis of triplet photosensitizer material (6-1) follows: Under nitrogen, a mixture of 3,4,9,10-perylenetetracarboxylic dianhydride (196.2 mg, 0.5 mmol), imidazole (952 mg, 14 mmol), 2-octyldodecylamine (0.38 mL, 42.0 mmol), and 4-amino-TEMPO (85.6 mg, 0.5 mmol) was stirred at 160 °C for 6 hours. After the reaction, the mixture was cooled to room temperature, and dichloromethane was added. The organic layer was washed with brine (3 × 200 mL), collected, and the organic solvent dried over anhydrous sodium sulfate. The crude product was concentrated by vacuum distillation and purified by column chromatography using silica gel and dichloromethane as the eluent to obtain a red solid (123.8 mg, 30% yield).

[0064] Example 4

[0065] The target molecule was characterized by infrared spectroscopy and matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry to obtain accurate information about the target molecule's structure. The specific results are as follows:

[0066] For formula (5-1), the infrared spectrum is shown below 1, 3305 Absorption peak corresponding to stretching vibration, indicating the presence of secondary amines in the structure ( ). 2920 and 2849 It is typical stretching vibration, related to the saturation of long-chain alkyl groups (sp 3 ) vibrations. 1729 It is the stretching vibration of carbonyl (C=O) and is located at 1730 Around 1688, which is consistent with the absorption characteristics of imide carbonyl. and 1648 It is the vibration of the aromatic ring C=C skeleton. 1510 and 1455 It is the skeletal vibration of C=C and C=N bonds in aromatic systems. 1378 、1347 , 1272 Belong to Bending vibration or vibration with CH2 and CH3 in alkyl side chains. 1178 and 1107 Corresponding to Stretching vibration. 804 and 747 Belong to aromatic ring Bending vibration.

[0067]

[0068] For formula (5-1), MALDI-TOF high-resolution accurate mass calibration is shown in 2 below. The target molecular formula is The theoretical mass-to-charge ratio is 1162.8663, the measured mass-to-charge ratio is 1162.8618, and the relative error is 3.9034%.

[0069] For formula (6-1), the infrared spectrum is shown below 3, 2918 and 2853 The absorption peak usually represents stretching vibrations, especially with methyl groups ( ) and methylene (-CH2) groups. 1730 It is the carbonyl (C=O) stretching vibration peak. 1600 The absorption peak is related to the C=C stretching vibration of the aromatic ring. 1241 and 1050 Absorption peak represents Stretching vibration. 1430 The absorption peak is Bending vibration peak. 1162 and 1119 Belong to aromatic ring Bending vibration.

[0070] For formula (6-1), MALDI-TOF high-resolution accurate mass calibration is shown in Figure 4. The target molecular formula is The theoretical mass-to-charge ratio is 824.5002, and the measured mass-to-charge ratio is 824.4958.

[0071] It should be noted that other compounds claimed in this application can be obtained by referring to the preparation methods of the above-mentioned embodiments, so they are not listed here one by one.

[0072] Example 5

[0073] The generation of singlet oxygen in the photosensitizer material in the molecular structure shown in formula (5-1) and formula (6-1) is monitored using the singlet oxygen scavenger 1,3-diphenylisobenzofuran (DPBF), including the following steps:

[0074] Prepare a toluene solution of photosensitizer with a concentration of mol / L, as mother solution A.

[0075] Prepare a chloroform solution of DPBF with a concentration of mol / L, as mother solution B.

[0076] Take mother liquor A and add it to 3 mL of toluene solution so that its absorbance at 532 nm is about 0.2, then add mother liquor B so that its absorbance at 414 nm is about 1.0 to obtain a mixed solution of mother liquor A and mother liquor B.

[0077] Under light-proof conditions, the mixed solution was irradiated with 532 nm light, and the decrease in the DPBF absorption peak intensity at different irradiation time intervals was monitored to detect the singlet oxygen generation state.

[0078] As shown in Figure 5 below, the perylene diimide-radical photosensitizer material (5-1) generates singlet oxygen in a toluene solution. At different irradiation times (0 seconds, 60 seconds, 120 seconds, 180 seconds, 240 seconds, 300 seconds, 360 seconds, 420 seconds, and 480 seconds), the DPBF absorption peak intensity changes linearly with irradiation time, and the DPBF absorption peak intensity gradually decreases with increasing irradiation time. Specifically, the DPBF absorption peak intensity decreases from 1.03267 to 0.85661 within 480 seconds, indicating that Formula (5-1) is a triplet photosensitizer that can efficiently generate singlet oxygen.

[0079] As shown in Figure 6 below, the perylene diimide-radical photosensitizer material (6-1) generates singlet oxygen in a toluene solution. At different irradiation times (0 seconds, 40 seconds, 80 seconds, 120 seconds, 160 seconds, 200 seconds, 240 seconds, and 280 seconds), the DPBF absorption peak intensity changes linearly with irradiation time, and the DPBF absorption peak intensity gradually decreases with increasing irradiation time. Specifically, the DPBF absorption peak intensity decreases from 1.04134 to 0.88345 within 280 seconds, indicating that Formula (6-1) is a triplet photosensitizer that can efficiently generate singlet oxygen.

[0080] Example 6

[0081] Triplet property test of perylene diimide-free radical photosensitizer material:

[0082] Nanosecond transient absorption spectroscopy measurements were performed using a nanosecond laser flash photolysis instrument (LP 980). The excitation light source was a tunable nanosecond laser (Surelite I-10) with an excitation wavelength range of 210 nm–2400 nm and a laser energy of approximately 15 mJ per pulse (500 nm). The measurement signal was digitized using a Tektronix TDS 3012B oscilloscope, and the data was recorded and processed using L900 software. During nanosecond transient absorption spectroscopy measurements, the sample must be kept under a nitrogen atmosphere to prevent oxygen quenching of the triplet state. Therefore, high-purity nitrogen was bubbled through the solution for approximately 15 minutes before the measurement.

[0083] The UV-visible absorption spectrum of the photosensitizer formula (5-1) in toluene solvent is shown in Figure 7. Based on the UV-visible absorption spectrum of the photosensitizer in toluene solvent, the test concentration for the nanosecond transient absorption spectroscopy test is determined to be M, the excitation wavelength is 610 nm. The nanosecond transient absorption spectrum of the photosensitizer in deoxygenated toluene solution at room temperature is shown in Figure 8. Excited state absorption peaks were observed within the 50 nm range, attributable to the transition from the first triplet excited state of the amino-substituted PBI moiety to a higher-energy triplet excited state. The decay curve of the transient species was measured at 520 nm, as shown in Figure 9. Equation (5-1) exhibits a long triplet lifetime, which, after fitting, is 7.6 μs.

[0084] The UV-visible absorption spectrum of the photosensitizer formula (6-1) in toluene solvent is shown in Figure 10. Based on the UV-visible absorption spectrum of the photosensitizer in toluene solvent, the test concentration for the nanosecond transient absorption spectroscopy test is determined to be M, with an excitation wavelength of 530 nm. The nanosecond transient absorption spectrum of the photosensitizer in deoxygenated toluene solution at room temperature is shown in Figure 11. Excited state absorption peaks were observed in the 565 nm range and are typical of the transition from the first triplet excited state of unsubstituted PBI to a higher-energy triplet excited state. The decay curve of the transient species was measured at 520 nm, as shown in 12 below. Equation (6-1) indicates a long triplet lifetime, which is fitted to a value of 5.0 μs.

[0085] Both photosensitizers represented by Equations (5-1) and (6-1) can efficiently undergo intersystem crossing to generate triplet states. This is due to the electron spin exchange between the free radical and the chromophore triplet state. In addition, the triplet state lifetime of the PBI-TEMPO photosensitizer is more than ten times longer than that of heavy atom-substituted PBI, indicating that free radical-based triplet photosensitizers do not quench the triplet state lifetime, demonstrating the reliability of designing efficient heavy atom-free photosensitizer molecules based on this mechanism.

[0086] It should be noted that other compounds claimed in this application can be obtained by referring to the experimental methods of the above-mentioned embodiments, so they are not listed here one by one.

[0087] Example 6

[0088] The mixture of the polymerizable component and the photoinitiator system of the present invention was heated by a 35 W xenon lamp (white light intensity: 80 mW / cm 2 ) to conduct photobleaching test (steady-state photolysis test). The experimental equipment is Shimadzu, Japan UV-visible absorption spectrometer, solvent is dichloromethane, coinitiator is tris (3-chloro-4-methylphenyl) hexyl borate tetrabutylammonium (NB). Test method is:

[0089] Under light-proof conditions, dichloromethane solutions of formula (5-1) were prepared with concentrations of M, and a dichloromethane solution of formula (6-1) with a concentration of M. And respectively add tris (3-chloro-4-methylphenyl) hexyl borate tetrabutylammonium to it so that its concentration is also M. After preparing the sample solution, bubble high-purity nitrogen gas through it for approximately 15 minutes. Use a UV absorption spectrometer to scan the absorption spectra of the sample before and after exposure to light for different times. The photobleaching curves for Equation (5-1) are shown in Figure 13, and those for Equation (6-1) are shown in Figure 14.

[0090] As the illumination time increases, the absorption peak intensity of the material gradually decreases, indicating that Formula (5-1) and Formula (6-1) have excellent photobleaching properties, which is very rare in chromophore-free radical photosensitizer materials.

[0091] Example 7

[0092] The mixture of the polymerizable component and the photoinitiator system of the present invention was heated by a 35 W xenon lamp (white light intensity: 80 mW / cm 2 ) for light-curing polymerization.

[0093] Furthermore, the total weight of the photopolymerizable composition is 100 wt %, and the weight of the photosensitizer accounts for 0.06 wt % to 0.10 wt % of the weight of the photopolymerizable composition.

[0094] Furthermore, the photoinitiator further includes a second photoinitiator and / or additives.

[0095] Furthermore, the second photoinitiator includes at least one of a benzophenone photoinitiator, an α-hydroxyketone photoinitiator, an α-aminoketone photoinitiator, a dimethylaminobenzophenone photoinitiator, a thioxanthone photoinitiator, a xanthone photoinitiator, a biimidazole photoinitiator, a triazine photoinitiator, and an acyl oxime photoinitiator.

[0096] The additives include at least one of a colorant, an alkali-soluble resin, an adhesion promoter, a surfactant, and a dispersant.

[0097] In the photopolymerization experiments, 0 wt%, 0.06 wt%, 0.08 wt%, and 0.10 wt% of the perylene diimide-radical photosensitizer material (Formula (5-1) or Formula (6-1)) were respectively combined with 0.5 wt% of tetrabutylammonium tris(3-chloro-4-methylphenyl)hexylborate (NB) to form a co-initiator system. The system was dispensed into four small sample bottles, dissolved in 0.12 mL of toluene solution, and then 1 mL of trimethylolpropane triacrylate (TMPTA) monomer was added. The system was protected from light, deoxygenated, and mixed thoroughly. The samples were irradiated with a 35 W xenon lamp, and the time it took for the monomer to fully cure was recorded.

[0098] The changes in the sample of Formula (5-1) before and after irradiation with a 35 W xenon lamp are shown below 15. As can be seen from the figure, without the addition of the perylene diimide-radical photosensitizer material, that is, at 0 wt% of Formula (5-1), the monomer cannot be cured. When 0.06 wt% of Formula (5-1) is added, the monomer is fully cured in 240 seconds. When 0.08 wt% of Formula (5-1) is added, the monomer is fully cured in 85 seconds. When 0.10 wt% of Formula (5-1) is added, the monomer is fully cured in 150 seconds.

[0099] The changes in the sample of Formula (6-1) before and after irradiation with a 35 W xenon lamp are shown below 16. As can be seen from the figure, when no perylene diimide-radical photosensitizer material is added, that is, when Formula (6-1) is present at 0 wt%, the monomer cannot be cured. When 0.06 wt% of Formula (6-1) is added, the monomer is fully cured in 25 seconds. When 0.08 wt% of Formula (6-1) is added, the monomer is fully cured in 20 seconds. When 0.10 wt% of Formula (6-1) is added, the monomer is fully cured in 32 seconds.

[0100] In summary, the present application provides a method for synthesizing a perylene diimide-TEMPO photosensitizer based on a free radical-induced chromophore that efficiently generates singlet oxygen. The method is simple to prepare, has a high yield, does not contain heavy atoms, and both the synthesis steps and the product are non-toxic, in line with the concept of green chemistry. The perylene diimide-TEMPO photosensitizer can efficiently generate triplet states and has a triplet lifetime of up to microseconds. More importantly, the photosensitizer exhibits good performance in photopolymerization and achieves the purpose of polymerization under white light. Therefore, the present application has certain practical and economic value in terms of synthesizing photosensitizers and photopolymerization.

[0101] Of course, the above embodiments of the present invention are merely examples for illustrating the present invention and are not intended to limit the specific implementation methods of the present invention. Those skilled in the art will appreciate that other variations or modifications can be made based on the above examples. It is not possible to provide detailed examples of all implementation methods here. Any obvious variations or modifications arising from the technical solutions of the present invention remain within the scope of protection of the present invention.

Claims

1. A perylene diimide-TEMPO compound, characterized in that: The structure of the compound is shown in general formula (1): ； Among them, R1 is ; R2 is or ; m, n are integers of 8-10; X is hydrogen; Alternatively, R1 and R2 are each independently selected from or ; m, n are integers of 8-10; the general formula contains at least one substituent X, X is or ; q1 and q2 are integers from 1 to 5.

2. The compound according to claim 1, characterized in that: R1 is ; R2 is , m and n are integers of 8-10; X is hydrogen.

3. The compound according to claim 2, characterized in that: m is 10 and n is 8.

4. The compound according to claim 1, characterized in that: R1 and R2 are ; m, n are integers of 8-10; the general formula includes one or two substituents X, X is ; q1 and q2 are integers from 1 to 5.

5. The compound according to claim 4, characterized in that: m is 10, n is 8; q1 is 1.

6. The compound according to claim 1, characterized in that: or or or or or .

7. The use of the compound according to any one of claims 1 to 6, characterized in that: The compound is used as a reagent for generating singlet oxygen.

8. The use of the compound according to any one of claims 1 to 6, characterized in that: Application of the compound in photopolymerization or photocatalysis.

9. The use according to claim 8, characterized in that The application of the compound in photopolymerization is specifically as follows: The photopolymerizable composition comprises a polymerizable monomer, a photosensitizer and a photoinitiator; The photosensitizer is the compound according to any one of claims 1 to 6, and the weight of the photosensitizer accounts for 0.06 wt% to 0.10 wt% of the weight of the photopolymerizable composition.

10. The use according to claim 9, characterized in that The photoinitiator further includes a second photoinitiator, or a second photoinitiator and an additive; The second photoinitiator includes at least one of a benzophenone photoinitiator, an α-hydroxyketone photoinitiator, an α-aminoketone photoinitiator, a dimethylaminobenzophenone photoinitiator, a thioxanthone photoinitiator, a xanthone photoinitiator, a biimidazole photoinitiator, a triazine photoinitiator, and an acyl oxime photoinitiator; The additives include at least one of a colorant, an alkali-soluble resin, an adhesion promoter, a surfactant, and a dispersant.

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