Benzimidazole quaternary ammonium salt and preparation method and application thereof
By synthesizing benzimidazole quaternary ammonium salt compounds, the problem of traditional fungicides pollute the environment is solved, and new fungicides with high efficiency and low toxicity are provided, which are used in coatings with anti-mildew and antibacterial and water treatment.
Patent Information
- Application Number
- CN202411599085.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-11
- Publication Date
- 2025-08-05
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
During the sterilization process, traditional fungicides will release toxic substances, pollute the environment and make it difficult to degrade, and destroy the ecological balance of microorganisms.
The preparation method of benzimidazole quaternary ammonium salt is used to synthesize benzimidazole quaternary ammonium salt through condensation, cyclization and reduction reactions, and is used for bactericide applications.
It has achieved efficient sterilization, low toxicity, good degradability, and low environmental pollution. It is suitable for coating anti-mildew and antibacterial and water treatment fields.
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Abstract
Description
Technical Field
[0001] The invention belongs to the field of sterilization, and particularly relates to a benzimidazole quaternary ammonium salt, a synthesis method and an application thereof. Background Art
[0002] Traditional fungicides are mainly oxidizing and non-oxidizing types. During the sterilization process, traditional fungicides often decompose and release toxic substances, polluting the environment. In addition, traditional fungicides are often difficult to degrade and will exist in the natural environment for a long time, destroying the ecological balance of microorganisms.
[0003] In view of the drawbacks of traditional fungicides, people have begun to focus on developing new fungicides. The present invention relates to a benzimidazole quaternary ammonium salt, which has the characteristics of good fungicidal effect, low toxicity, degradability, and low environmental pollution. It can be widely used in coating anti-mildew and antibacterial, water treatment and medical fields. Summary of the Invention
[0004] The present invention aims to solve the above-mentioned technical problems and provides a novel benzimidazole quaternary ammonium salt compound, a preparation method thereof and an application thereof.
[0005] The purpose of the present invention can be achieved through the following technical solutions:
[0006] Benzimidazole quaternary ammonium salt compound, its structural formula is as follows:
[0007]
[0008] A preparation method of the above-mentioned benzimidazole quaternary ammonium salt compound, the synthetic route of the method is as follows:
[0009]
[0010] The method of preparing a benzimidazole quaternary ammonium salt compound comprises the following steps:
[0011] (1) N-methyl-2-nitroaniline and 4-vinylbenzoic acid are condensed in a polar aprotic solvent with a condensing agent to obtain intermediate I;
[0012] (2) Under acidic conditions, intermediate I reacts with a reducing agent to obtain intermediate II;
[0013] (3) Intermediate II is heated with iodomethane in a polar aprotic solvent to obtain a benzimidazole quaternary ammonium salt.
[0014] In the above preparation method: the polar aprotic solvent in step (1) is DMF or DMSO, and the condensing agent is EDCI.
[0015] In the above preparation method, the molar ratio of the condensing agent in step (1), (1) N-methyl-2-nitroaniline and 4-vinylbenzoic acid is 1-2:1-2:1-2.
[0016] In the above preparation method: the acid described in step (2) is glacial acetic acid, and the volume mass ratio of the glacial acetic acid to the intermediate I is 80-120 mL:8-12 g.
[0017] In the above preparation method, the reducing agent in step (2) is zinc powder, the reaction temperature is reflux temperature, and the molar ratio of zinc powder to intermediate I is 3 to 8:1.
[0018] In the above preparation method: the polar aprotic solvent in step (3) is acetonitrile and tetrahydrofuran, and the reaction temperature is the solvent reflux temperature.
[0019] In the above preparation method: the molar ratio of the intermediate II described in step (3) to methyl iodide is 1:1-5.
[0020] In the technical solution of the present invention, the compound is used as a fungicide. DETAILED DESCRIPTION
[0021] The present invention will be further described below with reference to the following examples, but the scope of protection of the present invention is not limited thereto: Example 1
[0022] 4-Vinylbenzoic acid (9.74 g, 65.72 mmol) was dissolved in 50 ml of DMF and cooled to 0-5°C. EDCI (9.01 g, 78.87 mmol) was added in portions. After stirring for 1 h, N-methyl-2-nitroaniline (10 g, 65.72 mmol) was added in portions. After the addition was complete, the mixture was stirred at room temperature for 12 h. 500 ml of water was added and the mixture was extracted three times with 100 ml of ethyl acetate. The ethyl acetate layer was collected, dried, and spin-dried to give 15.10 g of a yellow oil (Intermediate I) with a purity of 95.3% and a yield of 85.00%.
[0023] 1 H NMR(500MHz,Chloroform-d)δ8.04(m,1H),7.90–7.83(m,3H),7.77(1H),7.50– 7.44(m,2H),7.08(m,1H),6.70(m,1H),5.58(m,1H),5.50(m,1H),3.48(s,3H).
[0024] Intermediate I (10 g, 35.42 mmol) was dissolved in 100 mL of glacial acetic acid, and zinc powder (11.58 g, 177.12 mmol) was added. The mixture was heated under reflux for 2 h. After the reaction was detected to be complete, the mixture was filtered and the filtrate was evaporated to dryness. 1 N sodium hydroxide solution was added to adjust the mixture to alkalinity, filtered, and dried to obtain 6.22 g of light yellow crystals (Intermediate II) with a purity of 98.2% and a yield of 75%. 1 H NMR (500MHz, Chloroform-d) δ7.84–7.76(m,2H),7.78–7.70(m,1H),7.47–7.40(m,3H),7.36–7.26(m,2H),6.70(m,1H),5.53(m,2H),3.97(s,3H).
[0025] Intermediate II (10 g, 42.68 mmol) was dissolved in 30 ml of acetonitrile, and iodomethane (18.17 g, 128.04 mmol) was added. The mixture was heated under reflux for 4 h. After the reaction was completed, the temperature was lowered and the solvent was evaporated to dryness to obtain 13.81 g of light yellow crystals with a purity of 99.3% and a yield of 86.00%.
[0026] 1 H NMR (500MHz, Chloroform-d) δ7.71–7.62(m,1H),7.55–7.47(m,1H),7.47–7.41(m,1H),5.49(m,1H),3.14(s,3H).
[0027] Example 2
[0028] 4-Vinylbenzoic acid (9.74 g, 65.72 mmol) was dissolved in 50 ml of DMSO and cooled to 0-5°C. EDCI (9.01 g, 78.87 mmol) was added portionwise and stirred for 1 h. N-methyl-2-nitroaniline (10 g, 65.72 mmol) was then added portionwise. After the addition was complete, the mixture was stirred at room temperature for 12 h. 500 ml of water was added and the mixture was extracted three times with 100 ml of ethyl acetate. The ethyl acetate layer was collected, dried, and spin-dried to give 16.5 g of a yellow oil (Intermediate I) with a purity of 96.5% and a yield of 92.88%.
[0029] 1 H NMR(500MHz,Chloroform-d)δ8.04(m,1H),7.90–7.83(m,3H),7.77(1H),7.50– 7.44(m,2H),7.08(m,1H),6.70(m,1H),5.58(m,1H),5.50(m,1H),3.48(s,3H).
[0030] The preparation of intermediate II is the same as in Example 1.
[0031] The preparation of the benzimidazole quaternary ammonium salt compound was the same as in Example 1, with a yield of 89.7% and a purity of 97.5%.
[0032] 1 H NMR (500MHz, Chloroform-d) δ7.71–7.62(m,1H),7.55–7.47(m,1H),7.47–7.41(m,1H),5.49(m,1H),3.14(s,3H).
[0033] Example 3
[0034] The preparation of intermediate I and intermediate II is the same as in Example 1.
[0035] Intermediate II (10 g, 42.68 mmol) was dissolved in 30 ml of tetrahydrofuran, and iodomethane (18.17 g, 128.04 mmol) was added. The mixture was heated under reflux for 4 h. After the reaction was completed, the temperature was lowered and the solvent was evaporated to obtain 12.8 g of light yellow crystals with a purity of 97.2% and a yield of 82.58%. 1 H NMR (500 MHz, Chloroform-d) δ7.71–7.62 (m, 1H), 7.55–7.47 (m, 1H), 7.47–7.41 (m, 1H), 5.49 (m, 1H), 3.14 (s, 3H). Performance test
[0036] Sterilization test: According to the Technical Specifications for Disinfection, 1-methyl-2-(4-vinylphenyl)-1H-benzo[d]imidazole and Example 1 were subjected to sterilization test.
[0037] Table 1 Results of bactericidal experiments with 1-methyl-2-(4-vinylphenyl)-1H-benzo[d]imidazole
[0038]
[0039] It can be seen from Table 1 that 1-methyl-2-(4-vinylphenyl)-1H-benzo[d]imidazole has almost no bactericidal effect on pathogenic microorganisms.
[0040] Table 2 Example 1 sterilization test results
[0041]
[0042] Example 4
[0043] According to the "Technical Specifications for Disinfection", 1-methyl-2-(4-vinylphenyl)-1H-benzo[d]imidazole and Example 1 were tested for skin irritation.
[0044] Table 3 Skin irritation test results of 1-methyl-2-(4-vinylphenyl)-1H-benzo[d]imidazole and Example 1
[0045]
[0046] Conclusion: As shown in Table 3, the irritation intensity of the quaternary ammonium salt prepared by the present invention is mild irritation.
[0047] Example 5
[0048] According to the "Technical Specifications for Disinfection", 1-methyl-2-(4-vinylphenyl)-1H-benzo[d]imidazole and Example 1 were tested for skin allergic reactions.
[0049] Table 4 Results of skin allergy test on 1-methyl-2-(4-vinylphenyl)-1H-benzo[d]imidazole and Example 1
[0050]
[0051] Example 6
[0052] Table 5 Inactivation Experimental Results of 1-Methyl-2-(4-vinylphenyl)-1H-benzo[d]imidazole and Example 1 on Novel Coronavirus Infection According to the WS / T "Laboratory Evaluation Standard for Disinfection Effect of Novel Coronavirus Infection", the inactivation rate of novel coronavirus infection is shown in the table below.
[0053]
Claims
1. A benzimidazole quaternary ammonium salt compound, characterized in that: Its structural formula is shown below:
2. A method for preparing the benzimidazole quaternary ammonium salt compound according to claim 1, wherein:
3. The preparation method according to claim 2, wherein: The method comprises the following steps: (1) N-methyl-2-nitroaniline and 4-vinylbenzoic acid are condensed in a polar aprotic solvent with a condensing agent to obtain intermediate I; (2) Under acidic conditions, intermediate I reacts with a reducing agent to obtain intermediate II; (3) Intermediate II is heated with iodomethane in a polar aprotic solvent to obtain a benzimidazole quaternary ammonium salt.
4. The preparation method according to claim 3, wherein: The polar aprotic solvent in step (1) is DMF or DMSO, the condensing agent is EDCI, and the reaction temperature is 0-5°C.
5. The preparation method according to claim 4, characterized in that: The molar ratio of the condensing agent, N-methyl-2-nitroaniline and 4-vinylbenzoic acid in step (1) is 1-2:1-2:1-2.
6. The preparation method according to claim 3, wherein: The acid in step (2) is glacial acetic acid, and the volume mass ratio of the glacial acetic acid to the intermediate I is 80-120 mL: 8-14 g.
7. The preparation method according to claim 3, characterized in that: The reducing agent in step (2) is zinc powder, the reaction temperature is reflux temperature, and the molar ratio of the zinc powder to the intermediate I is 3 to 8:
1.
8. The preparation method according to claim 3, wherein: The polar aprotic solvents in step (3) are acetonitrile and tetrahydrofuran, and the reaction temperature is the solvent reflux temperature.
9. The preparation method according to claim 3, wherein: The molar ratio of the intermediate II in step (3) to methyl iodide is 1:1-5.
10. Use of the compound according to claim 1 as a fungicide.