Photoinitiator and preparation method thereof

Abstract

The invention relates to the field of organic photocuring materials, in particular to a photoinitiator and a preparation method thereof. The photoinitiator provides an innovative glycosyl-quaternary ammonium salt dual modification strategy based on the TPO-L photoinitiator, in the molecular structure of the TPO-L photoinitiator, a glycosyl modification unit and a quaternary ammonium salt group are introduced at the same time, water solubility and biocompatibility are improved through a glycosyl part, the antibacterial performance is remarkably improved through the quaternary ammonium salt group, the migration rate of the initiator is reduced, and the photoinitiator has the advantages that the photoinitiator can be used for preparing the antibacterial agent. A synergistic effect is formed, and the comprehensive performance of the photoinitiator is comprehensively optimized.

Description

Technical Field

[0001] The present invention relates to the field of organic photocurable materials, and particularly relates to a photoinitiator and a preparation method thereof. Background Art

[0002] Photoinitiators play an important role in waterborne photocuring applications such as ultraviolet (UV) curable coatings, inks, 3D printing, etc. Methyl-substituted benzoyl phenylphosphonate (TPO-L) photoinitiators are widely used in various photocuring systems due to their efficient light absorption characteristics and initiation ability. However, TPO-L itself has strong hydrophobicity, low solubility in waterborne systems, and poor dispersibility, resulting in insufficient photoinitiation efficiency and limiting its application scope in waterborne photocuring systems. At the same time, TPO-L and some of its derivatives have a relatively high mobility in the cured coating, presenting certain biosafety hazards and being difficult to meet the application requirements of high-safety fields such as medical materials and food packaging.

[0003] In response to the above problems, the existing technologies mainly focus on introducing hydrophilic groups or using glycosylation modification strategies to improve the water solubility of TPO-L and other photoinitiators. For example, there have been studies on glycosylation modification of small molecule photoinitiators such as Irgacure 2959 [Liska, R., Knaus, S., Gruber, H. et al. Carbohydrate modified photoinitiators. Surface Coatings International 83, 297–303 (2000). https: / / doi.org / 10.1007 / BF02692730] to enhance their water solubility and biocompatibility; the macromolecular initiator Alg-2959 [Huang X, Zhang Y, Li F, et al. Highly efficient alginate-based macromolecular photoinitiator for crosslinking and toughening gelatin hydrogels. J Polym Sci. 2020; 58: 1439–1449. https: / / doi.org / 10.1002 / pol.20200138] reported in the literature also improved the water dispersibility and low mobility performance of the material through the hydrophilicity of alginate. The application of these technical routes has indeed solved the problems of water solubility and mobility to a certain extent.

[0004] However, the existing glycosylated photoinitiators and their macromolecular modification systems still have the following disadvantages and deficiencies: (1) The photoinitiation efficiency is still limited: Although the glycosyl-modified photoinitiator has certain hydrophilicity, its photopolymerization rate in aqueous systems is usually still low, unable to meet the industrial requirements of high-efficiency and rapid curing. (2) Lack of antibacterial function: Neither glycosyl modification nor Alg-2959 modification involves or can significantly enhance antibacterial activity, unable to meet the strict requirements for antibacterial properties in medical dressings, food packaging, etc. (3) There is still insufficient control over the migration rate: Some macromolecular modified photoinitiators still have a migration risk of >1%, unable to fully meet the low migration rate requirements in sensitive environments (such as food contact materials). (4) The improvement of biocompatibility is limited: Although glycosylation can improve biocompatibility, in practical applications with multiple additives and complex formulations, the overall biological safety and environmental friendliness of the system still need to be further improved. SUMMARY OF THE INVENTION

[0005] In view of the above-mentioned deficiencies of existing photoinitiators, the present invention provides a photoinitiator and its preparation method.

[0006] The technical solution of the present invention is achieved as follows: A photoinitiator is provided, and its general molecular structure formula is as follows:

[0007] Wherein, R is a glycosyl group, X⁻ is an anion, and R1, R2, and R3 are the same or different C1–C8 straight-chain or branched-chain alkyl groups, benzyl groups, hydroxyalkyl groups, or substituted benzyl groups.

[0008] In a preferred embodiment of the present invention, the glycosyl group is a monosaccharide, disaccharide, or polysaccharide, and the monosaccharide is glucose, arabinose, galactose, or xylose.

[0009] In a preferred embodiment of the present invention, R is selected from one of the following groups: .

[0010] In a preferred embodiment of the present invention, X⁻ is a halogen anion, sulfonate ion, carboxylate ion, or other inorganic acid root ion.

[0011] In a preferred embodiment of the present invention, the molecular formula of the photoinitiator is selected from the following:

[0012]

[0013]

[0014] .

[0015] On the other hand, the present invention also provides a method for preparing a photoinitiator, and the preparation process is as follows:

[0016] Specifically, it includes the following steps: S1. Add NaI to the solvent in which TPO-L is dissolved, and carry out a de-ethylation reaction to generate compound 2. The purified compound 2 is reacted with bromoethane to generate intermediate 3; S2. React the purified intermediate 3 with bromo-peracetylated sugar 4 under the condition of a basic catalyst, and purify to obtain a peracetylated glycosyl-substituted TPO-L derivative 5; S3. After dissolving the obtained peracetylated glycosyl-substituted TPO-L derivative 5, add an appropriate amount of acidic ion exchange resin to hydrolyze and remove the acetyl protecting group to obtain a glycosyl-modified TPO-L derivative 6; S4. React the obtained glycosyl-modified TPO-L derivative 6 with N-bromosuccinimide to generate a bromine-containing derivative 7; S5. React the obtained bromine-containing derivative 7 with a trisubstituted amine, and purify to obtain a derivative 8 containing a quaternary ammonium salt and a glycosyl substitution.

[0017] In a preferred embodiment of the present invention, the obtained derivative 8 containing a quaternary ammonium salt and a glycosyl substitution is further subjected to ion exchange with an ammonium salt containing an anion in an aqueous solution to obtain a target compound T containing an anion.

[0018] Specifically, in a preferred embodiment of the present invention, the synthesis method is as follows: The first step: Dissolve TPO-L in an appropriate solvent, add NaI (1 equivalent), and stir and react at an appropriate temperature. This reaction is carried out at 65 °C. After the reaction is completed, a yellow precipitate is formed. The precipitate is collected by filtration and washed with an appropriate amount of n-hexane to remove unreacted substances. The washed product is dried under vacuum at 60 °C for 24 hours to obtain an intermediate. The yield of this step reaches 90.1%. The obtained intermediate is directly used for the next reaction.

[0019] The second step: Mix compound 2 and bromoethane (1 equivalent) in an appropriate ratio in acetone and stir and react overnight at room temperature. After the reaction is completed, the product is separated by column chromatography to obtain the key intermediate 3, and washed with an appropriate solvent to ensure purity.

[0020] Step 3: Dissolve intermediate 3 and bromo-peracetylated sugar (1 equivalent) in acetone according to the equivalent ratio, add potassium carbonate (1 equivalent) as a basic catalyst, and continue stirring the reaction at room temperature until the reaction is complete. After the reaction is completed, dissolve the reactants in dichloromethane by solvent extraction, and wash with pure water to remove impurities such as bromides. Then, perform drying treatment with anhydrous sodium sulfate, and finally concentrate the solution. In the concentrated solution, further separate and purify by dichloromethane / petroleum ether column chromatography to obtain a peracetylated glycosyl-substituted TPO-L derivative.

[0021] Step 4: Dissolve the obtained peracetylated glycosyl-substituted TPO-L derivative in dichloromethane, add an appropriate amount of acidic ion exchange resin, and stir overnight. This reaction hydrolyzes the acetyl protecting group and removes the protecting group. After the reaction is completed, remove the ion exchange resin by filtration to obtain the target product, namely the glycosyl-modified TPO-L photoinitiator.

[0022] Step 5: Dissolve the glycosyl-modified TPO-L derivative (Compound 6) in an appropriate amount of chloroform, slowly add an equimolar amount of N-bromosuccinimide (NBS), and stir the reaction at room temperature to generate a bromine-containing derivative (Compound 7). After the reaction is completed, confirm the completion of the reaction by TLC detection, and remove the solvent by rotary evaporation. The crude product can be further separated and purified by dichloromethane / petroleum ether column chromatography to obtain a high-purity bromine-containing derivative (Compound 7).

[0023] Step 6: Dissolve the obtained bromine- and glycosyl-substituted derivative (Compound 7) in anhydrous ethanol, add an equivalent amount of a trisubstituted amine (such as tributylamine, dimethyl-benzylamine, etc.), and stir the reaction at room temperature overnight. After the reaction is completed, remove the solvent by rotary evaporation to obtain a preliminary quaternary ammonium salt- and glycosyl-substituted derivative (Compound 8).

[0024] Step 7 (Ion exchange): Dissolve Compound 8 in an appropriate amount of aqueous solution, add various ammonium salt solutions (such as ammonium chloride, ammonium iodide, etc.) for ion exchange reaction to generate the target compound T with different anions. After the ion exchange is completed, remove the water by freeze-drying or rotary evaporation to obtain a pure product of the target compound T.

[0025] The compound prepared by the present invention can be used as a photoinitiator in the fields of green environmental protection materials, medical coatings, degradable coatings, drug delivery systems, etc.

[0026] The beneficial effects are as follows: The present invention first proposes a molecular design strategy for glycosyl-quaternary ammonium salt dual-modified methyl-substituted benzoyl phenylphosphonate photoinitiators, giving full play to the synergistic effect of glycosyl modification and the introduction of quaternary ammonium salts, bringing the following important technological breakthroughs: (1) Synergistic innovation of dual modification Glycosyl modification unit: It can improve the solubility and dispersibility of photoinitiators in aqueous photocuring systems, and significantly improve their water solubility and biocompatibility.

[0027] Quaternary ammonium salt group: It endows the photoinitiator with good antibacterial activity. At the same time, through cation exchangeability, it effectively reduces the migration rate of the photoinitiator, and improves the application safety of the photoinitiator in high-safety fields such as medical treatment and food contact.

[0028] The synergy of the two: It breaks through the limitation that a single modified initiator in the prior art is difficult to balance water solubility, photoinitiation efficiency, low migration and antibacterial properties, and realizes the synergistic improvement of multi-dimensional properties such as water solubility, photoinitiation efficiency, low migration rate and antibacterial properties.

[0029] (2)Construction and diversity of representative compounds A variety of representative compounds are provided. The diversity of these representative compounds in structure and function meets the specific application requirements in different fields (such as medical dressings, food packaging, environmental protection coatings, etc.), and significantly improves the scalability and applicability of photoinitiators.

[0030] (3)Excellent multi-dimensional properties Six-dimensional performance indexes of the photoinitiator efficiency, water solubility, curing rate, optical quality of the film layer, migration rate, antibacterial activity and biocompatibility of the representative compounds were systematically evaluated.

[0031] The performance data shows that the photoinitiator of the present invention exhibits rapid curing (curing within 56 s), high photoinitiator efficiency (>76%), low migration rate (<1%), antibacterial zone diameter of 6-7 mm, and cell proliferation rate >95% in the aqueous photocuring system, far superior to the control products such as commercially available TPO-L and Alg-2959 reported in the literature. Specific implementation mode

[0032] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0033] The present invention will be further described in detail below in conjunction with embodiments.

[0034] Based on the compound synthesis, the present invention tests the performance of the glycosyl-quaternary ammonium salt bifunctional modified methyl-substituted benzoyl phenylphosphonate photoinitiator through the following evaluation methods: 1 Water solubility test The synthesized photoinitiator samples (10 mg each) were separately added to 10 mL of deionized water. After ultrasonic-assisted dispersion for 10 min, they were allowed to stand for 1 h. After filtration through a 0.45 μm filter membrane, the absorbance was measured using a UV-visible spectrophotometer, and the water solubility was calculated by combining with the standard curve. The average value was taken from three parallel experiments.

[0035] 2 Photoinitiating efficiency test In a typical waterborne acrylate photocuring formulation (hydroxyethyl acrylate: polyurethane acrylate = 1:1, containing 1.0 wt% photoinitiator), the photoinitiator was uniformly mixed and spin-coated on a KBr sheet (thickness about 20 μm). Irradiation was carried out using 365 nm ultraviolet light (50 mW / cm²), and the infrared spectral changes of the C = C double bond were recorded in real time (RT-FTIR). The double bond conversion rate (DBC) at 60 s and the maximum reaction rate were calculated, and the average value was taken from three parallel experiments.

[0036] 3 UV curing effect test The same formulation was spin-coated on a PET film (thickness 30 μm), irradiated using 365 nm ultraviolet light (50 mW / cm²), the time required for complete curing was recorded, and the optical quality of the film layer was observed, including the flatness and uniformity of the film surface, etc.

[0037] 4 Migration test Cured film pieces (1×1 cm) were prepared and immersed in deionized water at 37°C for 7 days (changing the water daily). The concentration of the migrated substance was analyzed by UV-Vis, and the migration rate was calculated. The average value was taken from three parallel experiments.

[0038] 5 Antibacterial performance test Staphylococcus aureus and Escherichia coli were separately inoculated on agar plates, and cured photoinitiator film pieces (diameter 6 mm) were placed on the surface of the culture medium. After culturing at 37°C for 24 h, the diameter of the inhibition zone was measured, and the average value was taken from three parallel experiments.

[0039] 6 Biocompatibility test L929 cells were inoculated in 96-well plates. After culturing for 24 h, the film pieces were added and culturing was continued for 24 h. The relative cell proliferation rate was determined using the CCK-8 method, and the average value was taken from three parallel experiments.

[0040] Through the above multi-dimensional performance tests, the present invention verified the comprehensive advantages of the glycyl-quaternary ammonium salt bifunctional modified methyl-substituted benzoyl phenylphosphonate photoinitiators in terms of water solubility, photoinitiating efficiency, antibacterial activity, low migration and biocompatibility, etc., demonstrating the broad prospects and practical application value of the materials of the present invention in waterborne photocuring applications.

[0041] Example 1: Synthesis of TPO-L photoinitiator B-1 modified with β-D-glucosyl and tri-n-butyl quaternary ammonium salt

[0042] Dissolve TPO-L (B-1-1, molecular weight 316.12, 10 g, 31.61 mmol) in 50 mL of acetone, and add NaI (B-1-2, 10 g, 31.61 mmol). The reaction is stirred at 65 °C for 15 minutes, and then continue to stir until complete. After the reaction, a yellow precipitate is formed. The precipitate is collected by filtration and washed twice with 10 mL of n-hexane to remove unreacted substances. The washed product is dried in vacuo at 60 °C for 24 hours to obtain the intermediate B-1-2.

[0043] Mix B-1-2 (intermediate 31.61 mmol) with bromoethane (1 equivalent, 5.0 g, 31.61 mmol) in acetone and stir the reaction overnight at room temperature. After the reaction, it is separated by column chromatography to obtain the key intermediate B-1-3. HRMS (ESI⁺) Calcd for C18H21O4P [M+H]⁺: 332.1189, Found: 332.1192 Dissolve B-1-3 (10 g, 30.12 mmol) and 1-bromo-2, 3, 4, 6-tetra-O-acetyl-α-D-glucose (B-1-4, 10 g, 30.12 mmol) in a 1:1 equivalent ratio in 50 mL of acetone, add potassium carbonate (1 equivalent, 4.3 g, 31.61 mmol) as a catalyst, and stir the reaction at room temperature for 12 hours. After the reaction is completed, the reactants are dissolved in dichloromethane by solvent extraction and washed with deionized water to remove impurities. It is dried using anhydrous sodium sulfate and finally further separated and purified by dichloromethane / petroleum ether column chromatography to obtain B-1-5 (2, 3, 4, 6-tetra-O-acetyl-α-D-glucose-substituted TPO-L derivative). Yield 85%. 1 H NMR(500 MHz, Chloroform) δ7.49–7.13 (m, 1H), 6.80(s,1H), 6.05–5.72 (m,1H), 5.32 (dd, J = 5.5, 2.6 Hz, 1H), 4.68 (ddd, J = 22.9,11.9, 8.4Hz, 1H), 4.16 (dd, J = 24.1, 12.5Hz, 1H), 3.90 (dd, J= 24.6, 12.5Hz, 1H), 3.68–3.42 (m, 1H), 2.27 (s, 1H), 2.22 (s, 1H), 2.03 (d, J = 10.1Hz, 2H). HRMS(ESI⁺) Calcd for C31H37O13P [M+H]⁺: 648.2013, Found: 648.2009 The obtained B-1-5 (6.48 g, 10 mmol) was dissolved in 10 mL of anhydrous dichloromethane, and an appropriate amount of acidic ion exchange resin was added to remove the acetyl protecting group. Under nitrogen protection, the reaction solution was stirred overnight at room temperature. After the reaction was completed, the ion exchange resin was removed by filtration to obtain the target product B-1 (β-D-glucosyl modified TPO-L photoinitiator). The dichloromethane in the filtered solution was removed by solvent evaporation, and the residue was washed several times with cold diethyl ether to collect the white solid product B-1-6. The final product was a white solid with a yield of 82%. 1 H NMR (500MHz) δ 6.80 (s, 1H), 5.70 (s, 1H), 5.07 (d, J = 14.6Hz, 1H), 4.28 (dd, J = 14.7, 7.1Hz, 1H), 4.02 (t, J = 7.0 Hz, 1H), 3.84–3.33 (m, 4H), 2.43 (s, 1H), 2.27 (s, 2H), 2.22 (s, 3H), 1.86(d, J = 18.5Hz, 1H). HRMS (ESI⁺) Calcd for C23H29O9P [M+H]⁺: 480.1523, Found: 480.1519 The β-D-glucosyl modified TPO-L derivative (B-1-6, 0.05 mol, 24.71 g) was dissolved in an appropriate amount of chloroform and stirred evenly. An equimolar amount of N-bromosuccinimide (NBS, 0.05 mol, 8.90 g) was slowly added, and the reaction was stirred at room temperature. The progress of the reaction was monitored by thin layer chromatography (TLC) until the reaction was complete. After the reaction was completed, the solvent was removed by rotary evaporation to obtain the crude product. The crude product was purified by column chromatography using dichloromethane / petroleum ether as the eluent to obtain a high-purity bromine- and glycosyl-substituted derivative (B-1-7, molecular weight 573.37 g / mol). 11H NMR (500 MHz, Chloroform) δ 7.54–7.17 (m, 5H), 6.95 (s, 2H), 5.76 (s, 1H), 5.52 (d, J J = 6.6 Hz, 1H), 4.66 (s, 2H), 4.32–4.00 (m, 2H), 3.92–3.18 (m, 8H), 2.23 (s, 1H), 2.22 (s, 6H), 2.15 (s, 1H), 1.25 (s, 1H). The purified B-1-7 (0.05 mol, 28.67 g) was dissolved in an appropriate amount of absolute ethanol and stirred evenly. Tri-n-butylamine (0.05 mol, 9.26 g) in an equimolar amount was added to the solution, and the mixture was stirred at room temperature overnight. After the reaction was completed, the ethanol solvent was removed by rotary evaporation to obtain a crude product. The crude product was dissolved in warm ethanol, allowed to stand and cool to room temperature, and then placed in an ice bath to promote crystal precipitation. The crystals were collected by vacuum filtration and washed with cold ethanol to obtain the target compound: the TPO-L photoinitiator B-1 modified with β-D-glucosyl and tri-n-butyl quaternary ammonium salt, which appeared as a white or light yellow solid. 1 1H NMR (500 MHz, Chloroform) δ 7.50–7.08 (m, 5H), 6.83 (s, 2H), 6.08 (s, 1H), 5.11 (d, J J = 4.8 Hz, 1H), 4.98 (s, 2H), 4.28–3.25 (m, 16H), 2.30 (s, 1H), 2.22 (s, 6H), 1.93–1.70 (m, 6H), 1.55 (s, 1H), 1.38 (s, 1H), 1.34–1.11 (m, 6H), 0.89 (dd, J J = 13.4, 12.8 Hz, 9H). Example 2: Synthesis of the TPO-L photoinitiator B-2 modified with β-D-glucosyl, di-n-butyl and isobutyl quaternary ammonium salt

[0044] The bromine-containing and β-D-glucosyl-substituted derivative (B-1-7, molecular weight 573.37 g / mol, 0.05 mol, 28.67 g) obtained in Example 1 was dissolved in an appropriate amount of absolute ethanol and stirred evenly. Di-n-butyl-isobutylamine B-2-1 (molecular weight 185.21 g / mol, 0.05 mol, 9.26 g) in an equimolar amount was added to this solution, and the mixture was stirred at room temperature overnight.

[0045] After the reaction was completed, the ethanol solvent was removed by rotary evaporation to obtain the crude product. The crude product was dissolved in warm ethanol, allowed to stand and cool to room temperature, and then placed in an ice bath to promote crystal precipitation. The crystals were collected by vacuum filtration and washed with cold ethanol to obtain the target compound: TPO-L photoinitiator B-2 modified with β-D-glucosyl and di-n-butyl-isobutyl quaternary ammonium salt. 1 H NMR(500MHz, Chloroform) δ7.58–7.16 (m, 5H), 6.83 (s, 2H), 5.42–5.13 (m, 1H),4.93 (s, 2H), 4.25–3.93 (m, 2H), 3.92–3.06 (m, 14H), 2.66–2.35 (m, 2H), 2.24(d, J = 19.2Hz, 7H), 2.02 (s, 1H), 1.91–1.69 (m, 4H), 1.53 (s, 1H), 1.39–1.08(m, 4H), 1.02–0.72 (m, 12H). Example 3: Synthesis of TPO-L photoinitiator B-3 modified with β-D-glucosyl and dimethyl and benzyl quaternary ammonium salt

[0046] The bromine-containing and β-D-glucosyl-substituted derivative (B-1-7, molecular weight 573.37 g / mol, 0.05 mol, 28.67 g) obtained in Example 1 was dissolved in an appropriate amount of anhydrous ethanol and stirred evenly. An equimolar amount of dimethyl-benzylamine (B-3-1) (molecular weight 135.10 g / mol, 0.05 mol, 6.76 g) was added to this solution, and the mixture was stirred at room temperature overnight.

[0047] After the reaction was completed, the ethanol solvent was removed by rotary evaporation to obtain the crude product. The crude product was dissolved in warm ethanol, allowed to stand and cool to room temperature, and then placed in an ice bath to promote crystal precipitation. The crystals were collected by vacuum filtration and washed with cold ethanol to obtain the target compound: TPO-L photoinitiator B-3 modified with β-D-glucosyl and dimethyl-benzyl quaternary ammonium salt. 1 H NMR(500MHz, Chloroform) δ7.45–7.25 (m, 5H), 7.25–7.11 (m, 5H), 6.82 (s, 2H),5.07 (d, J= 12.6Hz, 1H), 4.86 (s, 2H), 4.66 (s, 2H), 4.16–3.81 (m, 3H), 3.79–3.35 (m, 7H), 3.27 (s, 6H), 2.46 (d, J = 17.6Hz, 2H), 2.27 (s, 1H), 2.22 (s,6H), 1.35 (s, 1H). Example 4: Synthesis of TPO-L photoinitiator B-4 modified with β-D-glucosyl, dibutyl, and benzyl quaternary ammonium salt

[0048] Dissolve the bromine-containing and β-D-glucosyl-substituted derivative (B-1-7, molecular weight 573.37 g / mol, 0.05 mol, 28.67 g) obtained in Example 1 in an appropriate amount of absolute ethanol and stir evenly. Add an equimolar amount of dibutyl-benzylamine (B-4-1, molecular weight 219.20 g / mol, 0.05 mol, 10.96 g) to this solution and stir the reaction overnight at room temperature.

[0049] After the reaction is completed, remove the ethanol solvent by rotary evaporation to obtain a crude product. Dissolve the crude product in warm ethanol, let it stand and cool to room temperature, and then place it in an ice bath to promote crystal precipitation. Collect the crystals by vacuum filtration and wash them with cold ethanol to obtain the target compound: TPO-L photoinitiator B-4 modified with β-D-glucosyl and dibutyl-benzyl quaternary ammonium salt, which appears as a white or light yellow solid. 1 H NMR (500MHz, Chloroform) δ7.50–7.09 (m, 10H), 6.83 (s,2H), 5.19 (d, J = 12.8Hz, 1H), 4.84 (s, 1H), 4.73 (s, 2H), 4.53 (s, 2H), 4.34–3.95 (m, 2H), 3.96–3.22 (m, 13H), 2.22 (s, 6H), 2.01–1.54 (m, 5H), 1.47–1.10(m, 5H), 1.03–0.60 (m, 6H). Example 5: Synthesis of TPO-L photoinitiator A-5 modified with β-D-galactosyl and tributyl quaternary ammonium salt

[0050]

[0051] B-1-3 (10 g, 30.12 mmol) and 1-bromo-2, 3, 4, 6-tetra-O-acetyl-α-D-galactose (B-5-1, 10 g, 24.39 mmol) were dissolved in 50 mL of acetone in a 1:1 equivalent ratio, and potassium carbonate (1 equivalent, 4.3 g, 31.61 mmol) was added as a catalyst. The reaction mixture was stirred at room temperature for 12 hours. After the reaction was completed, the reaction progress was monitored by thin-layer chromatography (TLC) to confirm complete conversion. After the reaction ended, it was cooled to room temperature, and the reaction solution was poured into ice water. The pH of the solution was adjusted to approximately 3 with 1 M hydrochloric acid to precipitate the solid product. The precipitated solid was collected by filtration and washed with deionized water until neutral to remove excess hydrochloric acid and solvents. The solid intermediate after the reaction was dissolved in dichloromethane, dried over anhydrous sodium sulfate, and further filtered. Then the solution was concentrated to dryness. Purification by dichloromethane / petroleum ether column chromatography gave B-5-2 (2, 3, 4, 6-tetra-O-acetyl-α-D-galactose-substituted TPO-L derivative) with a yield of 80%. 1 HNMR (500MHz, Chloroform) δ7.45–7.17 (m, 5H), 6.80 (s, 2H), 6.03–5.77 (m, 2H), 5.32 (dd, J =5.6, 2.5Hz,1H), 4.68 (ddd, J =22.8, 11.9, 8.2Hz, 2H), 4.16 (dd, J =24.1, 12.5Hz, 1H), 3.90(dd, J =24.6, 12.5Hz, 1H), 3.69–3.48 (m, 4H), 2.27 (s, 3H), 2.22 (s, 6H), 2.03(d, J = 10.1Hz, 12H).HRMS (ESI⁺)CalcdforC32H39O13P[M+H]⁺:662.2153, Found:662.2149. 6.62 g of B-5-2 was dissolved in 10 mL of anhydrous dichloromethane, and an appropriate amount of acidic ion exchange resin was added to remove the acetyl protecting groups. Under nitrogen protection, the reaction solution was stirred at room temperature overnight. After the reaction was completed, the ion exchange resin was removed by filtration to obtain the target product B-5-3 (β-D-galactosyl-modified TPO-L photoinitiator). The filtered solution was evaporated to remove dichloromethane, and then washed with cold ether several times to collect the white solid product B-2. The final product was a white solid with a yield of 75%. 11H NMR (500 MHz, Chloroform) δ 7.47–7.18 (m, 5H), 6.80 (s, 2H), 5.50 (s, 1H), 4.66 (d, J J = 15.2 Hz, 1H), 4.07 (dd, J J = 16.7, 15.3 Hz, 1H), 3.82–3.49 (m, 7H), 3.44 (dd, J J = 24.7, 10.3 Hz, 1H), 3.24 (dt, J J = 18.6, 10.4 Hz, 1H), 2.27 (s, 3H), 2.22 (s, 6H), 2.13 (s, 1H), 2.03 (s, 1H), 1.92 (s, 1H). HRMS (ESI⁺) Calcd for C24H31O9P [M+H]⁺: 494.1785, Found: 494.1779. The β-D-galactosyl-modified TPO-L derivative (B-5-3, molecular weight 494.17 g / mol, 0.05 mol, 24.71 g) was dissolved in an appropriate amount of chloroform and stirred evenly. An equimolar amount of N-bromosuccinimide (NBS, molecular weight 177.98 g / mol, 0.05 mol, 8.90 g) was slowly added, and the reaction was stirred at room temperature. The reaction progress was monitored by thin-layer chromatography (TLC) until the reaction was confirmed to be complete. After the reaction, the chloroform solvent was removed by rotary evaporation to obtain a crude product. The crude product was separated and purified by column chromatography using dichloromethane / petroleum ether as the eluent to obtain a high-purity bromine- and β-D-galactosyl-substituted derivative (B-5-4, molecular weight 573.37 g / mol). 1H NMR (500 MHz, Chloroform) δ 7.46–7.20 (m, 5H), 6.95 (s, 2H), 4.84 (s, 2H), 4.47 (d, J = 14.3 Hz, 1H), 4.11 (dd, J = 16.5, 14.4 Hz, 1H), 3.97 (dd, J = 18.9, 17.1 Hz, 1H), 3.78–3.12 (m, 8H), 2.22 (s, 6H), 2.10 (s, 1H), 1.78 (d, J = 12.6 Hz, 2H), 1.61 (s, 1H). Dissolve the purified B-5-4 (molecular weight 573.37 g / mol, 0.05 mol, 28.67 g) in an appropriate amount of absolute ethanol and stir evenly. Add an equimolar amount of tributylamine (B-5-5, molecular weight 185.21 g / mol, 0.05 mol, 9.26 g) to the solution and stir the reaction overnight at room temperature. After the reaction is completed, rotary evaporate to remove the ethanol solvent to obtain the crude product. Dissolve the crude product in warm ethanol, let it stand and cool to room temperature, and then place it in an ice bath to promote crystal precipitation. Collect the crystals by vacuum filtration and wash them with cold ethanol to obtain the target product: TPO-L photoinitiator A-5 modified with β-D-galactosyl and tri-n-butyl quaternary ammonium salt, presented as a white or light yellow solid. 1 HNMR (500MHz, Chloroform) δ7.47–7.17 (m, 5H),6.83 (s, 2H), 4.92 (s, 2H), 4.56 (d, J = 15.4Hz, 1H), 4.04 (dd, J = 17.4, 15.4Hz,1H), 3.87–3.03 (m, 15H), 2.22 (s, 6H), 2.01 (d, J = 10.4Hz, 2H), 1.82 (dq, J =30.5, 15.3Hz, 7H), 1.45–1.14 (m, 6H), 1.02 (s, 1H), 0.89 (dd, J = 13.4, 12.8Hz,9H). Example 6: Synthesis of TPO-L photoinitiator B-6 modified with β-D-galactosyl, di-n-butyl and isobutyl quaternary ammonium salt

[0052] Dissolve the bromine-containing and β-D-galactosyl-substituted derivative (B-5-4, molecular weight 573.37 g / mol, 0.05 mol, 28.67 g) obtained in Example 5 in an appropriate amount of absolute ethanol and stir evenly. Add an equimolar amount of di-n-butyl-isobutylamine B-6-1 (molecular weight 185.21 g / mol, 0.05 mol, 9.26 g) to this solution and stir the reaction overnight at room temperature.

[0053] After the reaction was completed, the ethanol solvent was removed by rotary evaporation to obtain the crude product. The crude product was dissolved in warm ethanol, allowed to stand and cool to room temperature, and then placed in an ice bath to promote crystal precipitation. The crystals were collected by vacuum filtration and washed with cold ethanol to obtain the target compound: TPO-L photoinitiator B-6 modified with β-D-galactosyl, di-n-butyl, and isobutyl quaternary ammonium salt. 1 HNMR(500MHz, Chloroform) δ7.56–7.09 (m, 5H), 6.82 (s, 2H), 4.74 (s, 2H), 4.55 (d, J = 15.4Hz, 1H), 4.25–3.03 (m, 16H), 2.53–2.25 (m, 1H), 2.22 (s, 6H), 2.01 (d, J = 10.4Hz, 2H), 1.93–1.63 (m, 5H), 1.48–1.12 (m, 4H), 0.93 (dt, J = 26.1,18.7Hz, 13H). Example 7: Synthesis of TPO-L photoinitiator B-7 modified with β-D-galactosyl, dimethyl, and benzyl quaternary ammonium salt

[0054] The bromine-containing and β-D-galactosyl-substituted derivative (B-5-4, molecular weight 573.37 g / mol, 0.05 mol, 28.67 g) obtained in Example 5 was dissolved in an appropriate amount of anhydrous ethanol and stirred evenly. An equimolar amount of dimethyl-benzylamine (B-7-1) (molecular weight 135.10 g / mol, 0.05 mol, 6.76 g) was added to this solution, and the mixture was stirred at room temperature overnight.

[0055] After the reaction was completed, the ethanol solvent was removed by rotary evaporation to obtain the crude product. The crude product was dissolved in warm ethanol, allowed to stand and cool to room temperature, and then placed in an ice bath to promote crystal precipitation. The crystals were collected by vacuum filtration and washed with cold ethanol to obtain the target compound: TPO-L photoinitiator B-7 modified with β-D-galactosyl, dimethyl, and benzyl quaternary ammonium salt. 1 H NMR(500MHz, Chloroform) δ 7.55–7.08 (m, 5H), 6.83 (s, 1H), 5.02 (d, J = 15.4Hz,1H), 4.61 (s, 2H), 4.23 (dd, J = 16.9, 15.6Hz, 1H), 3.91 (dd, J= 18.9, 17.1Hz, 1H), 3.79–3.36 (m, 4H), 3.33–3.09 (m, 3H), 2.22 (s, 3H), 2.13 (s, 1H), 1.75–1.11 (m, 2H). Example 8: Synthesis of TPO-L photoinitiator B-8 modified with β-D-galactosyl, dibutyl, and benzyl quaternary ammonium salt

[0056] Dissolve the bromine-containing and β-D-galactosyl-substituted derivative (B-5-4, molecular weight 573.37 g / mol, 0.05 mol, 28.67 g) obtained in Example 5 in an appropriate amount of absolute ethanol and stir evenly. Add equimolar dibutyl-benzylamine (B-8-1, molecular weight 219.20 g / mol, 0.05 mol, 10.96 g) to this solution and stir the reaction overnight at room temperature.

[0057] After the reaction is completed, remove the ethanol solvent by rotary evaporation to obtain a crude product. Dissolve the crude product in warm ethanol, let it stand and cool to room temperature, and then place it in an ice bath to promote crystal precipitation. Collect the crystals by vacuum filtration and wash them with cold ethanol to obtain the target compound: TPO-L photoinitiator B-8 modified with β-D-galactosyl, dibutyl, and benzyl quaternary ammonium salt, which appears as a white or light yellow solid. 1 H NMR (500MHz, Chloroform) δ7.63–7.02 (m, 10H), 6.82 (s,2H), 4.79 (s, 2H), 4.70 (s, 2H), 4.57 (d, J = 15.4Hz, 1H), 4.04 (dd, J = 17.3,15.4Hz, 1H), 3.89–2.95 (m, 13H), 2.22 (s, 6H), 2.01 (d, J = 10.4Hz, 2H), 1.81(dq, J = 30.5, 15.3Hz, 5H), 1.44–1.13 (m, 4H), 1.02 (s, 1H), 0.89 (dd, J = 13.4,12.8Hz, 6H). Example 9: Synthesis of TPO-L photoinitiator B-9 modified with β-D-xylosyl and tributyl quaternary ammonium salt

[0058] B-1-3 (10 g, 30.12 mmol) and 1-bromo-2, 3, 4-tri-O-acetyl-α-D-xylose (B-9-1, 10 g, 29.59 mmol) were dissolved in 50 mL of acetone in an equivalent ratio of 1:1. Potassium carbonate (1 equivalent, 4.3 g, 31.61 mmol) was added as a catalyst, and the reaction mixture was stirred at room temperature for 12 hours. After the reaction was completed, the reaction progress was monitored by thin-layer chromatography (TLC) to confirm complete conversion. After the reaction, the reaction mixture was cooled to room temperature, poured into ice water, and the pH of the solution was adjusted to ≈3 with 1 M hydrochloric acid to precipitate the solid product. The precipitated solid was collected by filtration, washed with deionized water until neutral to remove excess hydrochloric acid and solvent.

[0059] The solid intermediate after the reaction was dissolved in dichloromethane, dried over anhydrous sodium sulfate, and further filtered. Then the solution was concentrated to dryness. Purification by dichloromethane / petroleum ether column chromatography gave B-9-2 (2, 3, 4-tri-O-acetyl-α-D-xylose-substituted TPO-L derivative) with a yield of 80%. 1 HNMR (500MHz, Chloroform) δ7.41–7.11 (m, 5H),6.78 (s, 2H), 5.54–5.38 (m, 1H), 5.35 (d, J = 9.6Hz, 1H), 5.25 (td, J = 5.2,3.6Hz, 1H), 5.00 (dd, J = 10.3, 3.7Hz, 1H), 3.99 (dd, J = 24.8, 5.2Hz, 1H), 3.80–3.44 (m, 5H), 2.26 (s, 3H), 2.21 (s, 6H), 2.01 (s, 9H). HRMS (ESI⁺)CalcdforC29H35O11P[M+H]⁺:590.1993, Found:590.1991. 5.90 g of B-9-2 was dissolved in 10 mL of anhydrous dichloromethane, and an appropriate amount of acidic ion exchange resin was added to remove the acetyl protecting group. Under nitrogen protection, the reaction solution was stirred at room temperature overnight. After the reaction was completed, the ion exchange resin was removed by filtration to obtain the target product B-3 (β-D-xylosyl-modified TPO-L photoinitiator). The filtered solution was evaporated to remove dichloromethane, and then washed with cold ether several times to collect the white solid product B-9-3. The final product was a white solid with a yield of 75%. 1HNMR (500 MHz, Chloroform) δ 7.47–7.15 (m, 5H), 6.80 (s, 2H), 5.08 (d, J J = 7.2 Hz, 1H), 4.17–3.78 (m, 5H), 3.70–3.52 (m, 4H), 3.28 (dd, J J = 24.7, 4.9 Hz, 1H), 2.27 (s, 3H), 2.22 (s, 6H), 2.15 (s, 1H), 1.73 (s, 1H). HRMS (ESI⁺) Calcd for C23H29O8P [M + H]⁺: 464.1673, Found: 464.1669. The β-D-xylosyl-modified TPO-L derivative (B-9-3, molecular weight 464.16 g / mol, 0.05 mol, 23.21 g) was dissolved in an appropriate amount of chloroform and stirred evenly. An equimolar amount of N-bromosuccinimide (NBS, molecular weight 177.98 g / mol, 0.05 mol, 8.90 g) was slowly added, and the reaction was stirred at room temperature. The reaction progress was monitored by thin-layer chromatography (TLC) until the reaction was confirmed to be complete. After the reaction, the chloroform solvent was removed by rotary evaporation to obtain the crude product. The crude product was separated and purified by column chromatography using dichloromethane / petroleum ether as the eluent to obtain high-purity bromine-containing and β-D-xylosyl-substituted TPO-L (B-9-4, molecular weight 543.35 g / mol). 1 HNMR (500 MHz, Chloroform) δ 7.48–7.14 (m, 5H), 6.95 (s, 2H), 4.75 (s, 2H), 4.39 (d, J J = 7.1 Hz, 1H), 4.17 (dd, J J = 9.7, 7.2 Hz, 1H), 3.98 (q, J J = 5.3 Hz, 1H), 3.85 (ddd, J J = 30.2, 17.3, 5.2 Hz, 2H), 3.66–3.45 (m, 4H), 3.34 (dd, J J = 24.8, 5.4 Hz, 1H), 3.09 (s, 1H), 2.47 (s, 1H), 2.22 (s, 6H), 1.49 (s, 1H). The purified B-9-4 (molecular weight 543.35 g / mol, 0.05 mol, 27.17 g) was dissolved in an appropriate amount of absolute ethanol and stirred evenly. An equimolar amount of tributylamine (B-9-5, molecular weight 185.21 g / mol, 0.05 mol, 9.26 g) was added to the solution, and the mixture was stirred at room temperature overnight. After the reaction was completed, the ethanol solvent was removed by rotary evaporation to obtain a crude product. The crude product was dissolved in warm ethanol, allowed to stand and cool to room temperature, and then placed in an ice bath to promote crystal precipitation. The crystals were collected by vacuum filtration and washed with cold ethanol to obtain the target product: the TPO-L photoinitiator B-9 modified with β-D-xylosyl and tri-n-butyl quaternary ammonium salt, which appeared as a white or light yellow solid. 1 HNMR (500MHz, Chloroform) δ7.52–7.21 (m,5H), 6.82 (s, 2H), 5.14 (d, J = 7.1Hz, 1H), 4.75 (s, 2H), 4.34–3.74 (m, 4H),3.72–3.21 (m, 11H), 2.98 (s, 1H), 2.24 (d, J = 20.0Hz, 7H), 1.91–1.65 (m, 6H),1.43 (s, 1H), 1.36–1.03 (m, 6H), 0.89 (dd, J = 13.4, 12.8Hz, 9H). Example 10: Synthesis of the TPO-L photoinitiator B-10 modified with β-D-xylosyl, di-n-butyl and isobutyl quaternary ammonium salt

[0060] The bromine-containing and β-D-xylosyl-substituted TPO-L (B-9-4, molecular weight 543.35 g / mol, 0.05 mol, 27.17 g) obtained in Example 9 was dissolved in an appropriate amount of absolute ethanol and stirred evenly. An equimolar amount of di-n-butyl-isobutylamine (B-10-1, molecular weight 185.21 g / mol, 0.05 mol, 9.26 g) was added to the solution, and the mixture was stirred at room temperature overnight.

[0061] After the reaction was completed, the ethanol solvent was removed by rotary evaporation to obtain a crude product. The crude product was dissolved in warm ethanol, allowed to stand and cool to room temperature, and then placed in an ice bath to promote crystal precipitation. The crystals were collected by vacuum filtration and washed with cold ethanol to obtain the target product: the TPO-L photoinitiator B-10 modified with β-D-xylosyl and di-n-butyl-isobutyl quaternary ammonium salt. 11H NMR (500 MHz, Chloroform) δ 7.54–7.18 (m, 5H), 6.83 (s, 2H), 5.06 (d, J J = 12.1 Hz, 1H), 4.73 (s, 2H), 4.28–3.00 (m, 16H), 2.87 (s, 1H), 2.38 (dtd, J J = 22.8, 12.7, 2.7 Hz, 1H), 2.20 (d, J J = 19.6 Hz, 7H), 1.82 (p, J J = 15.3 Hz, 4H), 1.39–1.08 (m, 4H), 1.08–0.64 (m, 12H). Example 11: Synthesis of TPO-L photoinitiator B-11 modified with β-D-xylosyl and dimethyl and benzyl quaternary ammonium salt

[0062] The bromine-containing and β-D-xylosyl-substituted TPO-L (B-9-4, molecular weight 543.35 g / mol, 0.05 mol, 27.17 g) obtained in Example 9 was dissolved in an appropriate amount of absolute ethanol and stirred evenly. To this solution was added an equimolar amount of dimethyl-benzylamine (B-11-1, molecular weight 135.10 g / mol, 0.05 mol, 6.76 g), and the mixture was stirred at room temperature overnight.

[0063] After the reaction was completed, the ethanol solvent was removed by rotary evaporation to obtain a crude product. The crude product was dissolved in warm ethanol, allowed to stand and cool to room temperature, and then placed in an ice bath to promote crystal precipitation. The crystals were collected by vacuum filtration and washed with cold ethanol to obtain the target compound: TPO-L photoinitiator B-11 modified with β-D-xylosyl and dimethyl-benzyl quaternary ammonium salt, which appeared as a white or light yellow solid. 1H NMR (500 MHz, Chloroform) δ 7.57–7.13 (m, 10H), 6.83 (s, 2H), 5.33 (d, J = 9.0 Hz, 1H), 4.65 (s, 2H), 4.61 (s, 2H), 4.22–3.16 (m, 15H), 2.54 (d, J = 34.8 Hz, 2H), 2.22 (s, 6H), 1.78 (s, 1H). Example 12: Synthesis of TPO-L photoinitiator B-12 modified with β-D-xylosyl and di-n-butyl and benzyl quaternary ammonium salt

[0064] Dissolve the bromine-containing and β-D-xylosyl-substituted TPO-L (B-9-4, molecular weight 543.35 g / mol, 0.05 mol, 27.17 g) obtained in Example 9 in an appropriate amount of absolute ethanol and stir evenly. Add equimolar di-n-butyl-benzylamine (B-8-1, molecular weight 219.20 g / mol, 0.05 mol, 10.96 g) to this solution and stir the reaction overnight at room temperature.

[0065] After the reaction is completed, remove the ethanol solvent by rotary evaporation to obtain a crude product. Dissolve the crude product in warm ethanol, let it stand and cool to room temperature, and then place it in an ice bath to promote crystal precipitation. Collect the crystals by vacuum filtration and wash them with cold ethanol to obtain the target product: the TPO-L photoinitiator B-12 modified with β-D-xylosyl and di-n-butyl-benzyl quaternary ammonium salt, which appears as a white or light yellow solid. 1HNMR (500MHz, Chloroform) δ7.58–7.04 (m, 10H), 6.83 (s, 2H),5.35 (d, J = 8.9Hz, 1H), 4.71 (s, 2H), 4.62 (s, 2H), 4.22–3.24 (m, 13H), 2.50(d, J = 26.6Hz, 2H), 2.22 (s, 6H), 2.02–1.57 (m, 5H), 1.41–1.10 (m, 4H), 0.89(t, J = 13.1Hz, 6H). Example 13: Synthesis of the TPO-L photoinitiator B-13 modified with β-D-arabinofuranosyl and tri-n-butyl quaternary ammonium salt

[0066] Dissolve B-1-3 (10 g, 30.12 mmol) and 1-bromo-2, 3, 4-tri-O-acetyl-α-D-arabinose (B-13-1, 10 g, 29.59 mmol) in a 1:1 equivalent ratio in 50 mL of acetone, add potassium carbonate (1 equivalent, 4.3 g, 31.61 mmol) as a catalyst, and stir the reaction at room temperature for 12 hours. After the reaction is completed, monitor the reaction progress by thin-layer chromatography (TLC) to confirm that the reaction has been completely converted. After the reaction is completed, cool to room temperature, pour the reaction solution into ice water, adjust the pH of the solution to ≈3 with 1M hydrochloric acid, and precipitate the solid product. Collect the precipitated solid by filtration and wash it with deionized water until neutral to remove excess hydrochloric acid and solvent. 1 HNMR (500MHz, Chloroform) δ7.64–7.03 (m, 5H), 6.83 (s,2H), 5.31 (d,J = 11.5 Hz, 1H), 4.89 (s, 2H), 4.38–3.74 (m, 4H), 3.67–3.17 (m, 12H), 2.22 (s, 6H), 2.09 (s, 1H), 1.82 (p, J = 15.4 Hz, 6H), 1.54 (s, 1H), 1.36–1.06 (m, 6H), 0.89 (dd, J = 13.4, 12.7 Hz, 9H). The solid intermediate after the reaction was dissolved in dichloromethane, dried over anhydrous sodium sulfate, further filtered, and then the solution was concentrated to dryness. It was purified by column chromatography of dichloromethane / petroleum ether to obtain B-13-2 (TPO-L derivative substituted with 2, 3, 4-tri-O-acetyl-α-D-arabinose), with a yield of 80%. 1 1H NMR (500 MHz, Chloroform) δ 7.42–7.07 (m, 5H), 6.79 (s, 2H), 5.44 (s, 1H), 5.33 (d, J = 28.5 Hz, 2H), 4.92 (s, 1H), 3.94 (s, 1H), 3.60 (t, J = 22.2 Hz, 5H), 2.27 (s, 3H), 2.22 (s, 6H), 2.02 (s, 9H). HRMS (ESI⁺) Calcd for C29H35O11P [M + H]⁺: 590.1993, Found: 590.1991. 5.90 g of B-13-3 was dissolved in 10 mL of anhydrous dichloromethane, and an appropriate amount of acidic ion exchange resin was added to remove the acetyl protecting group. Under nitrogen protection, the reaction solution was stirred overnight at room temperature. After the reaction was completed, the ion exchange resin was removed by filtration to obtain the target product B-4 (β-D-arabinose-modified TPO-L photoinitiator). The dichloromethane in the filtered solution was removed by solvent evaporation, and it was washed several times with cold ether, and the white solid product B-4 was collected. The final product was a white solid, with a yield of 75%. 1HNMR (500 MHz, Chloroform) δ 7.50–7.12 (m, 5H), 6.80 (s, 2H), 5.02 (s, 1H), 4.09 (s, 1H), 4.01–3.73 (m, 4H), 3.70–3.37 (m, 5H), 2.27 (s, 3H), 2.22 (s, 6H), 1.51 (s, 1H), 1.39 (s, 1H). HRMS (ESI⁺) Calcd for C23H29O8P [M+H]⁺: 464.1673, Found: 464.1671. The β-D-arabinofuranosyl-modified TPO-L derivative (B-13-3, molecular weight 464.16 g / mol, 0.05 mol, 23.21 g) was dissolved in an appropriate amount of chloroform and stirred evenly. An equimolar amount of N-bromosuccinimide (NBS, molecular weight 177.98 g / mol, 0.05 mol, 8.90 g) was slowly added, and the reaction was stirred at room temperature. The reaction progress was monitored by thin-layer chromatography (TLC) until the reaction was confirmed to be complete. After the reaction, the chloroform solvent was removed by rotary evaporation to obtain the crude product. The crude product was separated and purified by column chromatography using dichloromethane / petroleum ether as the eluent to obtain high-purity bromine-containing and β-D-arabinofuranosyl-substituted TPO-L (B-13-4, molecular weight 543.35 g / mol). 1 HNMR (500 MHz, Chloroform) δ 7.53–7.15 (m, 5H), 6.95 (s, 2H), 4.87 (s, 2H), 4.82 (d, J = 6.6 Hz, 1H), 4.10–3.24 (m, 9H), 2.40–1.98 (m, 8H), 1.51 (s, 1H). The purified B-13-4 (molecular weight 543.35 g / mol, 0.05 mol, 27.17 g) was dissolved in an appropriate amount of absolute ethanol and stirred evenly. An equimolar amount of tributylamine (B-13-5, molecular weight 185.21 g / mol, 0.05 mol, 9.26 g) was added to this solution, and the mixture was stirred at room temperature overnight. After the reaction was completed, the ethanol solvent was removed by rotary evaporation to obtain a crude product. The crude product was dissolved in warm ethanol, allowed to stand and cool to room temperature, and then placed in an ice bath to promote crystal precipitation. The crystals were collected by vacuum filtration and washed with cold ethanol to obtain the target product: the TPO-L photoinitiator B-13 modified with β-D-arabinofuranosyl and tri-n-butyl quaternary ammonium salt, which appeared as a white or light yellow solid. 1HNMR (500MHz, Chloroform) δ7.64–7.03(m, 5H), 6.83 (s, 2H), 5.31 (d, J = 11.5Hz, 1H), 4.89 (s, 2H), 4.38–3.74 (m,4H), 3.67–3.17 (m, 12H), 2.22 (s, 6H), 2.09 (s, 1H), 1.82 (p, J = 15.4Hz,6H), 1.54 (s, 1H), 1.36–1.06 (m, 6H), 0.89 (dd, J = 13.4, 12.7Hz, 9H). Example 14: Synthesis of the TPO-L photoinitiator B-14 modified with β-D-arabinofuranosyl and di-n-butyl and isobutyl quaternary ammonium salt

[0067] The bromine-containing and β-D-arabinofuranosyl-substituted TPO-L (B-13-4, molecular weight 543.35 g / mol, 0.05 mol, 27.17 g) obtained in Example 9 was dissolved in an appropriate amount of absolute ethanol and stirred evenly. An equimolar amount of di-n-butyl-isobutylamine (B-14-1, molecular weight 185.21 g / mol, 0.05 mol, 9.26 g) was added to this solution, and the mixture was stirred at room temperature overnight.

[0068] After the reaction was completed, the ethanol solvent was removed by rotary evaporation to obtain a crude product. The crude product was dissolved in warm ethanol, allowed to stand and cool to room temperature, and then placed in an ice bath to promote crystal precipitation. The crystals were collected by vacuum filtration and washed with cold ethanol to obtain the target product: the TPO-L photoinitiator B-14 modified with β-D-arabinofuranosyl and di-n-butyl and isobutyl quaternary ammonium salt. 1HNMR (500 MHz, Chloroform) δ 7.57–7.05 (m, 5H), 6.83 (s, 2H), 4.86 (d, J = 6.8 Hz, 1H), 4.75 (s, 2H), 4.21–3.03 (m, 15H), 2.93 (s, 1H), 2.39 (ddt, J = 15.4, 12.7, 6.4 Hz, 1H), 2.19 (d, J = 26.0 Hz, 7H), 1.83 (p, J = 15.3 Hz, 4H), 1.42–0.71 (m, 17H). Example 15: Synthesis of TPO-L Photoinitiator B-15 Modified with β-D-Arabinofuranosyl and Dimethyl and Benzyl Quaternary Ammonium Salt

[0069] Dissolve the bromine-containing and β-D-arabinofuranosyl-substituted TPO-L (B-13-4, molecular weight 543.35 g / mol, 0.05 mol, 27.17 g) obtained in Example 9 in an appropriate amount of absolute ethanol and stir evenly. Add an equimolar amount of dimethyl-benzylamine (B-15-1, molecular weight 135.10 g / mol, 0.05 mol, 6.76 g) to this solution and stir the reaction overnight at room temperature.

[0070] After the reaction is completed, remove the ethanol solvent by rotary evaporation to obtain a crude product. Dissolve the crude product in warm ethanol, let it stand and cool to room temperature, and then place it in an ice bath to promote crystal precipitation. Collect the crystals by vacuum filtration and wash them with cold ethanol to obtain the target compound: TPO-L photoinitiator B-15 modified with β-D-arabinofuranosyl and dimethyl and benzyl quaternary ammonium salt. 1 HNMR (500 MHz, Chloroform) δ 7.45–7.07 (m, 10H), 6.83 (s, 2H), 5.32 (d, J = 9.0 Hz, 1H), 4.65 (s, 2H), 4.61 (s, 2H), 4.10 (dd, J = 13.1, 9.0 Hz, 1H), 3.94 (ddd, J = 19.2, 10.4, 3.8 Hz, 2H), 3.77 (dd, J = 24.8, 7.6 Hz, 1H), 3.59 (s, 4H), 3.50 (dd, J= 24.8, 7.6Hz, 1H), 3.30 (s, 6H), 2.58 (s, 1H), 2.51 (s, 1H), 2.22 (s, 6H), 1.78 (s, 1H). Example 16: Synthesis of TPO-L Photoinitiator B-16 Modified with β-D-Arabinofuranosyl and Di-n-butyl and Benzyl Quaternary Ammonium Salt

[0071] Dissolve the bromine-containing and β-D-arabinofuranosyl-substituted TPO-L (B-13-4, molecular weight 543.35 g / mol, 0.05 mol, 27.17 g) obtained in Example 9 in an appropriate amount of absolute ethanol and stir evenly. Add equimolar di-n-butyl-benzylamine (B-16-1, molecular weight 219.20 g / mol, 0.05 mol, 10.96 g) to this solution and stir the reaction overnight at room temperature.

[0072] After the reaction is completed, remove the ethanol solvent by rotary evaporation to obtain a crude product. Dissolve the crude product in warm ethanol, let it stand and cool to room temperature, and then place it in an ice bath to promote crystal precipitation. Collect the crystals by vacuum filtration and wash them with cold ethanol to obtain the target product: TPO-L photoinitiator B-16 modified with β-D-arabinofuranosyl and di-n-butyl and benzyl quaternary ammonium salt. 1HNMR (500 MHz, Chloroform) δ7.42–7.01 (m, 10H), 6.82 (s, 2H), 5.13 (d, J = 6.8Hz, 1H), 4.77 (s, 2H), 4.69 (s, 2H), 3.92 (dddd, J = 22.4, 18.1, 11.2, 5.9Hz, 4H), 3.64–3.53 (m, 4H), 3.44 (dt, J = 30.3, 10.1Hz, 5H), 2.81 (s, 1H), 2.24 (d, J = 18.5Hz, 7H), 1.81 (p, J = 15.3Hz, 4H), 1.41 (s, 1H), 1.36–1.05 (m, 4H), 0.89 (dd, J = 13.4, 12.8Hz, 6H). Example 17: Performance Evaluation To systematically verify the comprehensive performance of the glycosyl-quaternary ammonium salt bifunctional modified TPO-L photoinitiator of the present invention, representative compounds B-1 to B-16 were selected and compared with commercially available Irgacure2959, TPO-L and the reported Alg-2959 in the literature as controls. The specific experimental procedures and data are as follows.

[0073] Water solubility test Add 10 mg of each photoinitiator sample to 10 mL of deionized water, sonicate for 10 min, and then let it stand for 1 h. Filter (using a 0.45 μm filter membrane), measure the absorbance with a UV-visible spectrophotometer, and calculate the water solubility by combining with the standard curve. Repeat the experiment 3 times and take the average value.

[0074]

[0075] The water solubility of the experimental group was all above 3.0 mg / mL, significantly higher than that of commercially available Irgacure 2959 (0.5 mg / mL), TPO-L (<0.1 mg / mL), and literature-reported Alg-2959 (3.5 mg / mL), showing good water solubility and being suitable for waterborne photocuring applications.

[0076] Photoinitiator efficiency test Uniformly mix 1.0 wt% photoinitiator into a waterborne acrylate formulation (hydroxyethyl acrylate: polyurethane acrylate = 1:1), and spin-coat it on a KBr wafer (20 μm). Irradiate with 365 nm ultraviolet light (50 mW / cm²), record the change of C = C double bonds in the FTIR spectrum in real time, calculate the DBC and the maximum reaction rate at 60 s, repeat the experiment 3 times, and take the average value.

[0077]

[0078] The initiation efficiency of the experimental group was above 70%, and the maximum reaction rate was in the range of 0.024 - 0.028 s⁻¹, significantly better than that of the control group (Irgacure 2959 was only 53%, Alg-2959 was only 66%, and TPO-L was 48.2%), indicating that it had a faster reaction rate and higher efficiency.

[0079] UV curing effect test Spin-coat the photoinitiator formulation on a quartz wafer, irradiate with 365 nm ultraviolet light, record the complete curing time, and evaluate the film layer flatness by optical microscopy and naked eye observation.

[0080]

[0081] The complete curing time of the experimental group from B-1 to B-16 was all within 56 s, and the optical quality of the film layer was excellent (flat and defect-free), better than that of commercially available Irgacure 2959 (60 s, surface uneven), TPO-L (86 s, film layer with shrinkage holes and edge warping), and Alg-2959 (45 s, slight ripples).

[0082] Migration rate test Soak the film in deionized water at 37°C for 7 days, measure the migratory substances by UV-Vis, and calculate the migration rate.

[0083]

[0084] The migration rates of B-1 to B-16 are all lower than 1%, significantly lower than those of the commercially available and literature control groups (6.5% and 4.8%), with better low-migration characteristics, and are suitable for the food / medical fields.

[0085] Antibacterial activity test Place the cured film on the surface of the Staphylococcus aureus and Escherichia coli culture media, and culture at 37°C for 24 hours, and measure the diameter of the inhibition zone (mm).

[0086]

[0087] The diameters of the inhibition zones of the samples of B-1 to B-16 are all greater than 6 mm, showing good antibacterial properties; the antibacterial activities of the control groups Irgacure2959 and TPO-L are 0, and that of Alg-2959 is only 12 mm, which is significantly lower than that of the samples of the present invention.

[0088] Biocompatibility test Co-culture L929 cells with the film for 24 hours, and measure the cell proliferation rate (%) by the CCK-8 method.

[0089]

[0090] The cell proliferation rates of B-1 to B-16 are all above 95%, significantly superior to those of the commercially available Irgacure2959 (62%), TPO-L (64.2%) and the literature Alg-2959 (76%), showing excellent biocompatibility and meeting the requirements of medical and biological applications.

[0091] Through a detailed evaluation of six dimensions including water solubility, photoinitiating efficiency and maximum reaction rate, complete curing time and film layer optical quality, migration rate, antibacterial activity and biocompatibility, B-1 to B-16 show the following outstanding advantages: Water solubility: all are between 3.1 and 3.6 mg / mL, superior to the control. Photoinitiating efficiency (DBC) and rate: all >76%, much higher than those of commercially available and literature products. Curing speed and film layer quality: rapid curing within 56 s, and the film layer is flat and smooth. Low migration: <1%, suitable for food and medical packaging. Antibacterial property: the diameter of the inhibition zone reaches 6-7 mm, with antibacterial function. Biocompatibility: >95%, very suitable for fields with high safety requirements.

[0092] The glycosyl-quaternary ammonium salt dual-modified TPO-L photoinitiator of the present invention is superior to the control group in multiple performance dimensions and shows good comprehensive application potential.

[0093] The polymer structures listed above are only partial representatives, and other photoinitiator molecules with the same concept are within the scope of this patent protection.

[0094] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A photoinitiator, characterized in that, The general molecular structure formula is as follows: Wherein, R is a glycosyl group, X⁻ is an anion, and R1, R2, and R3 are the same or different C1–C8 straight-chain or branched-chain alkyl groups, benzyl groups, hydroxyalkyl groups, or substituted benzyl groups.

2. The photoinitiator according to claim 1, characterized in that, The glycosyl group is a monosaccharide, disaccharide, or polysaccharide, and the monosaccharide is glucose, arabinose, galactose, or xylose.

3. The photoinitiator according to claim 1, wherein R is selected from one of the following groups: 。 4. The photoinitiator according to claim 1, wherein X⁻ is a halogen anion, sulfonate ion, carboxylate ion, or other inorganic acid root ion.

5. The photoinitiator according to claim 1, wherein Selected from the following: 。 6. A preparation method of a photoinitiator, characterized in that, The preparation process is as follows: Specifically, it includes the following steps: S1. Add NaI to the solvent dissolving TPO-L, and perform a de-ethylation reaction to generate compound 2. The purified compound 2 reacts with bromoethane to generate intermediate 3; S2. React the purified intermediate 3 with bromo-peracetylated sugar 4 under the condition of a basic catalyst, and purify to obtain a peracetylated glycosyl-substituted TPO-L derivative 5; S3. After dissolving the obtained peracetylated glycosyl-substituted TPO-L derivative 5, add an appropriate amount of acidic ion exchange resin to hydrolyze and remove the acetyl protecting group to obtain a glycosyl-modified TPO-L derivative 6; S4. React the obtained glycosyl-modified TPO-L derivative 6 with N-bromosuccinimide to generate a bromine-containing derivative 7; S5. React the obtained bromine-containing derivative 7 with a trisubstituted amine, and purify to obtain a quaternary ammonium salt and glycosyl-substituted derivative 8.

7. The preparation method of the photoinitiator according to claim 6, characterized in that, It also includes the following anion exchange process: The obtained quaternary ammonium salt and glycosyl-substituted derivative 8 is further subjected to ion exchange with an ammonium salt containing an anion in an aqueous solution to obtain a target compound T containing an anion.

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