A method for synthesizing aromatic acyl chloride

Abstract

The present invention relates to the technical field of organic synthesis, and discloses a method for synthesizing aromatic acyl chloride. In the present invention, carboxyl-modified quaternized cardanol is added to a reaction kettle at room temperature, and then anhydrous aluminum trichloride and benzotrichloride are added. Then, the temperature is slowly raised to 70-75 °C. After the reaction stops generating bubbles, the temperature is further raised to 105-110 °C and the reaction is carried out for 1-2 hours. After the reaction is completed, the reaction solution is transferred to a distillation flask and distilled to obtain aromatic acyl chloride. The aromatic acyl chloride of the present invention solves the problems of high energy consumption or introduction of other organic solvents, and at the same time has good antibacterial effects.

Description

Technical Field

[0001] The present invention relates to the technical field of organic synthesis, and specifically to a method for synthesizing aromatic acyl chloride. Background Art

[0002] There are many existing processes for producing aromatic acyl chloride. Some directly use acyl chloride reagents, including phosgene, thionyl chloride, sulfonyl chloride, triphosgene, etc., and some use the chlorination hydrolysis process. Some of the acyl chloride reagents are highly toxic gases, and some are corrosive gases, which require extremely strict equipment and processes. For the existing processes, the biggest problem is that aromatic acids are all solids, and they need to be heated and melted or dissolved in a solvent during the acyl chlorination stage or the chlorination stage, either consuming heat or introducing new organic solvents, which have some impact on the product. Summary of the Invention

[0003] (I) Technical Problems to be Solved

[0004] In view of the deficiencies of the prior art, the present invention provides a method for synthesizing aromatic acyl chloride, which solves the problems of high energy consumption or introducing other organic solvents, and at the same time has a good antibacterial effect.

[0005] (II) Technical Solutions

[0006] To achieve the above object, the present invention provides the following technical solutions: A method for synthesizing aromatic acyl chloride, and the method for synthesizing aromatic acyl chloride is as follows:

[0007] Step 1: Add 3-pentadecylphenol to 6 - 10 mL of 1,2-dibromoethane, then add potassium hydroxide, and react at 68 - 75 °C. After completion, column chromatography separation is carried out to obtain 3-pentadecylphenoxyethyl bromide;

[0008] Step 2: Add 4-((dimethylamino)methyl)phenol, phthalic anhydride, and p-toluenesulfonic acid catalyst to N,N-dimethylformamide solvent, stir and disperse, and carry out an esterification reaction for 8 - 12 h. After the reaction, cool, wash, and dry to obtain Intermediate 1;

[0009] Step 3: Add Intermediate 1 and 3-pentadecylphenoxyethyl bromide to N,N-dimethylformamide solvent, stir and mix, and react at 75 - 90 °C. After completion, carry out vacuum distillation, wash, and dry to obtain carboxyl-modified quaternized cardanol;

[0010] Step 4: At room temperature, add carboxyl-modified quaternized cardanol to the reaction kettle, then add anhydrous aluminum trichloride and benzotrichloride, and then slowly heat up to 70 - 75 °C. After the reaction stops generating bubbles, heat up to 105 - 110 °C and react for 1 - 2 hours. After the reaction is completed, transfer the reaction solution to a distillation flask and distill to obtain aromatic acyl chloride.

[0011] Further, in the first step, the mass ratio of 3-pentadecylphenol to potassium hydroxide is 1.8 - 2.3 g : 0.55 - 0.6 g.

[0012] Further, in the first step, the reaction time is 4 - 7 h.

[0013] Further, in the second step, the mass ratio of 4-((dimethylamino)methyl)phenol, phthalic anhydride, and p-toluenesulfonic acid catalyst is 2.11 - 2.34 g : 1 - 1.12 g : 0.22 - 0.24 g.

[0014] Further, in the second step, the reaction temperature is 100 - 110 °C.

[0015] Further, in the third step, the mass ratio of intermediate 1 to 3-pentadecylphenoxyethyl bromide is 1.31 - 1.4 g : 2.3 - 2.6 g.

[0016] Further, in the third step, the reaction time is 6 - 8 h.

[0017] Further, in the fourth step, the mass ratio of carboxyl group-modified quaternized cardanol, anhydrous aluminum trichloride, and benzotrichloride is 1 g : 0.03 - 0.032 g : 0.8 - 1.1 g.

[0018] (III) Beneficial technical effects

[0019] In the present invention, carboxyl group-modified quaternized cardanol is added to a reaction kettle, then anhydrous aluminum trichloride and benzotrichloride are added, and then the temperature is slowly raised. After the reaction stops generating bubbles, the temperature is raised for further reaction. After the reaction is completed, the reaction solution is transferred to a distillation flask and distilled to obtain an aromatic acyl chloride.

[0020] The bromine in 3-pentadecylphenol and 1,2-bromoethane reacts to introduce bromine, thus obtaining 3-pentadecylphenoxyethyl bromide; the phenolic hydroxyl group in 4-((dimethylamino)methyl)phenol reacts with the acid anhydride in phthalic anhydride to generate a carboxyl group and introduce a tertiary amino group, thus obtaining intermediate 1; the tertiary amino group in intermediate 1 reacts with the bromine in 3-pentadecylphenoxyethyl bromide, thus obtaining carboxyl group-modified quaternized cardanol.

[0021] In the present invention, benzotrichloride is used as an acyl chloride reagent to react with the corresponding carboxyl group-modified quaternized cardanol aromatic acid under the catalysis of a Lewis acid, which can well solve the problems of high energy consumption or introduction of other organic solvents. At the same time, the quaternary ammonium salt contained in the aromatic acyl chloride has a good antibacterial effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is the structural formula of 3-pentadecylphenoxyethyl bromide. Detailed implementation mode Example 1

[0023] Step 1: Add 1.8 g of 3-pentadecylphenol to 6 mL of 1,2-dibromoethane, then add 0.55 g of potassium hydroxide, react at 68 °C for 4 h, and after completion, perform column chromatography separation to obtain 3-pentadecylphenoxyethyl bromide;

[0024] Step 2: Add 2.11 g of 4-((dimethylamino)methyl)phenol, 1 g of phthalic anhydride, and 0.22 g of p-toluenesulfonic acid catalyst to 30 mL of N,N-dimethylformamide solvent, stir and disperse, carry out an esterification reaction, react at 100 °C for 8 h, cool after the reaction, wash and dry to obtain Intermediate 1;

[0025] Step 3: Add 1.31 g of Intermediate 1 and 2.3 g of 3-pentadecylphenoxyethyl bromide to 35 mL of N,N-dimethylformamide solvent, stir and mix, react at 75 °C for 6 h, after completion, perform vacuum distillation, wash, and dry to obtain carboxyl-modified quaternized cardanol;

[0026] Step 4: At room temperature, add 1 g of carboxyl-modified quaternized cardanol to the reaction kettle, then add 0.03 g of anhydrous aluminum trichloride and 0.8 g of benzotrichloride, and then slowly heat up to 70 °C. After the reaction stops generating bubbles, heat up to 105 °C and react for 1 hour. After the reaction is completed, transfer the reaction solution to a distillation flask, distill to obtain aromatic acyl chloride. Example 2

[0027] Step 1: Add 2.3 g of 3-pentadecylphenol to 10 mL of 1,2-dibromoethane, then add 0.6 g of potassium hydroxide, react at 75 °C for 7 h, and after completion, perform column chromatography separation to obtain 3-pentadecylphenoxyethyl bromide;

[0028] Step 2: Add 2.34 g of 4-((dimethylamino)methyl)phenol, 1.12 g of phthalic anhydride, and 0.24 g of p-toluenesulfonic acid catalyst to 50 mL of N,N-dimethylformamide solvent, stir and disperse, carry out an esterification reaction, react at 110 °C for 12 h, cool after the reaction, wash and dry to obtain Intermediate 1;

[0029] Step 3: Add 1.4 g of Intermediate 1 and 2.6 g of 3-pentadecylphenoxyethyl bromide to 45 mL of N,N-dimethylformamide solvent, stir and mix, react at 90 °C for 8 h, after completion, perform vacuum distillation, wash, and dry to obtain carboxyl-modified quaternized cardanol;

[0030] Step 4: At room temperature, add 1 g of carboxyl-modified quaternized cardanol to the reaction kettle, then add 0.032 g of anhydrous aluminum trichloride and 1.1 g of benzotrichloride, and then slowly heat up to 75 °C. After the reaction stops generating bubbles, heat up to 110 °C and react for 2 hours. After the reaction is completed, transfer the reaction solution to a distillation flask and distill to obtain aromatic acyl chloride. Example 3

[0031] Step 1: Add 2.1 g of 3-pentadecylphenol to 8 mL of 1,2-dibromoethane, then add 0.58 g of potassium hydroxide, and react at 72 °C for 6 h. After completion, perform column chromatography separation to obtain 3-pentadecylphenoxyethyl bromide;

[0032] Step 2: Add 2.24 g of 4-((dimethylamino)methyl)phenol, 1.11 g of phthalic anhydride, and 0.23 g of p-toluenesulfonic acid catalyst to 40 mL of N,N-dimethylformamide solvent, stir and disperse, and carry out an esterification reaction. React at 105 °C for 10 h. After the reaction, cool, wash, and dry to obtain Intermediate 1;

[0033] Step 3: Add 1.35 g of Intermediate 1 and 2.5 g of 3-pentadecylphenoxyethyl bromide to 40 mL of N,N-dimethylformamide solvent, stir and mix, and react at 80 °C for 7 h. After completion, perform vacuum distillation, wash, and dry to obtain carboxyl-modified quaternized cardanol;

[0034] Step 4: At room temperature, add 1 g of carboxyl-modified quaternized cardanol to the reaction kettle, then add 0.031 g of anhydrous aluminum trichloride and 0.9 g of benzotrichloride, and then slowly heat up to 72 °C. After the reaction stops generating bubbles, heat up to 108 °C and react for 2 hours. After the reaction is completed, transfer the reaction solution to a distillation flask and distill to obtain aromatic acyl chloride. Example 4

[0035] Step 1: Add 1.8 g of 3-pentadecylphenol to 6 mL of 1,2-dibromoethane, then add 0.55 g of potassium hydroxide, and react at 68 °C for 4 h. After completion, perform column chromatography separation to obtain 3-pentadecylphenoxyethyl bromide;

[0036] Step 2: Add 2.11 g of 4-((dimethylamino)methyl)phenol, 1 g of phthalic anhydride, and 0.22 g of p-toluenesulfonic acid catalyst to 30 mL of N,N-dimethylformamide solvent, stir and disperse, and carry out an esterification reaction. React at 100 °C for 8 h. After the reaction, cool, wash, and dry to obtain Intermediate 1;

[0037] Step 3: Add 1.4 g of Intermediate 1 and 2.6 g of 3-pentadecylphenoxyethyl bromide to 45 mL of N,N-dimethylformamide solvent, stir and mix, react at 90 °C for 8 h, then perform vacuum distillation after completion, wash, and dry to obtain carboxyl-modified quaternary ammonium cardanol;

[0038] Step 4: At room temperature, add 1 g of carboxyl-modified quaternary ammonium cardanol to the reaction kettle, then add 0.031 g of anhydrous aluminum trichloride and 0.9 g of benzotrichloride, and then slowly heat up to 72 °C. After the reaction stops generating bubbles, further heat up to 108 °C and react for 2 hours. After the reaction is completed, transfer the reaction solution to a distillation flask, distill to obtain aromatic acyl chloride. Example 5

[0039] Step 1: Add 2.3 g of 3-pentadecylphenol to 10 mL of 1,2-dibromoethane, then add 0.6 g of potassium hydroxide, react at 75 °C for 7 h, and after completion, perform column chromatography separation to obtain 3-pentadecylphenoxyethyl bromide;

[0040] Step 2: Add 2.34 g of 4-((dimethylamino)methyl)phenol, 1.12 g of phthalic anhydride, and 0.24 g of p-toluenesulfonic acid catalyst to 50 mL of N,N-dimethylformamide solvent, stir and disperse, carry out esterification reaction, react at 110 °C for 12 h, cool after the reaction, wash and dry to obtain Intermediate 1;

[0041] Step 3: Add 1.35 g of Intermediate 1 and 2.5 g of 3-pentadecylphenoxyethyl bromide to 40 mL of N,N-dimethylformamide solvent, stir and mix, react at 80 °C for 7 h, then perform vacuum distillation after completion, wash, and dry to obtain carboxyl-modified quaternary ammonium cardanol;

[0042] Step 4: At room temperature, add 1 g of carboxyl-modified quaternary ammonium cardanol to the reaction kettle, then add 0.03 g of anhydrous aluminum trichloride and 0.8 g of benzotrichloride, and then slowly heat up to 70 °C. After the reaction stops generating bubbles, further heat up to 105 °C and react for 1 hour. After the reaction is completed, transfer the reaction solution to a distillation flask, distill to obtain aromatic acyl chloride. Example 6

[0043] Step 1: Add 2.1 g of 3-pentadecylphenol to 8 mL of 1,2-dibromoethane, then add 0.58 g of potassium hydroxide, react at 72 °C for 6 h, and after completion, perform column chromatography separation to obtain 3-pentadecylphenoxyethyl bromide;

[0044] Step 2: Add 2.11 g of 4-((dimethylamino)methyl)phenol, 1 g of phthalic anhydride, and 0.22 g of p-toluenesulfonic acid catalyst into 30 mL of N,N-dimethylformamide solvent, stir and disperse, and carry out the esterification reaction. React at 100 °C for 8 h. After the reaction, cool, wash, and dry to obtain Intermediate 1;

[0045] Step 3: Add 1.4 g of Intermediate 1 and 2.6 g of 3-pentadecylphenoxyethyl bromide into 45 mL of N,N-dimethylformamide solvent, stir and mix, and react at 90 °C for 8 h. After completion, carry out vacuum distillation, wash, and dry to obtain carboxyl-modified quaternized cardanol;

[0046] Step 4: At room temperature, add 1 g of carboxyl-modified quaternized cardanol into the reaction kettle, then add 0.032 g of anhydrous aluminum trichloride and 1.1 g of benzotrichloride, and then slowly heat up to 75 °C. After the reaction stops generating bubbles, heat up to 110 °C and react for 2 hours. After the reaction is completed, transfer the reaction solution to a distillation flask, distill to obtain the aromatic acyl chloride.

[0047] Comparative Example 1

[0048] The difference between this comparative example and Example 6 is that benzoic acid is used instead of carboxyl-modified quaternized cardanol.

[0049] Dissolve the aromatic acyl chloride and cast it into a film to make a thin slice with a radius of 1 cm; then use an inoculation loop to transfer bacteria into a sterile culture medium for cultivation to make a bacterial suspension with a concentration of 106 CFU / mL. Then transfer 0.5 mL of the bacterial suspension and drop it into a petri dish containing beef extract peptone medium, shake evenly, add the thin slice, and cultivate in a constant temperature incubator. After culturing for 48 h, measure the diameter of the antibacterial zone.

[0050] Table 1: Antibacterial test.

[0051] Project Escherichia coli (mm) Staphylococcus aureus (mm) Example 1 14.32 14.24 Example 2 15.16 14.36 Example 3 14.49 14.12 Example 4 15.11 14.66 Example 5 14.69 14.58 Example 6 14.57 14.39 Comparative Example 1 0 0

[0052] As can be seen from Table 1, the aromatic acyl chlorides of Examples 1-6 of the present invention have better antibacterial effects compared with Comparative Example 1.

[0053] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and changes can be made according to the content of this specification. These embodiments are selected and specifically described in this specification to better explain the principle and practical application of the present invention, so that those skilled in the art can well understand and utilize the present invention.

Claims

1. A method for synthesizing an aromatic acyl chloride, characterized in that, The synthesis method of the aromatic acyl chloride is as follows: Step 1: Add 3-pentadecylphenol to 6 - 10 mL of 1,2-dibromoethane, then add potassium hydroxide, and react at 68 - 75 °C. After completion, separate by column chromatography to obtain 3-pentadecylphenoxyethyl bromide; Step 2: Add 4-((dimethylamino)methyl)phenol, phthalic anhydride, and p-toluenesulfonic acid catalyst to N,N-dimethylformamide solvent, stir and disperse, and carry out an esterification reaction for 8 - 12 h. After the reaction, cool, wash, and dry to obtain Intermediate 1; Step 3: Add Intermediate 1 and 3-pentadecylphenoxyethyl bromide to N,N-dimethylformamide solvent, stir and mix, and react at 75 - 90 °C. After completion, carry out vacuum distillation, wash, and dry to obtain carboxyl-modified quaternized cardanol; Step 4: At room temperature, add carboxyl-modified quaternized cardanol to the reaction kettle, then add anhydrous aluminum trichloride and benzotrichloride, and slowly heat up to 70 - 75 °C. After the reaction stops generating bubbles, heat up to 105 - 110 °C and react for 1 - 2 hours. After the reaction is completed, transfer the reaction solution to a distillation flask and distill to obtain the aromatic acyl chloride; The reaction temperature in Step 2 is 100 - 110 °C; In Step 4, the mass ratio of carboxyl-modified quaternized cardanol, anhydrous aluminum trichloride, and benzotrichloride is 1 g : 0.03 - 0.032 g : 0.8 - 1.1 g.

2. The synthesis method of the aromatic acyl chloride according to claim 1, wherein In Step 1, the mass ratio of 3-pentadecylphenol to potassium hydroxide is 1.8 - 2.3 g : 0.55 - 0.6 g.

3. The synthesis method of the aromatic acyl chloride according to claim 1, characterized in that, The reaction time in Step 1 is 4 - 7 h.

4. The synthesis method of the aromatic acyl chloride according to claim 1, wherein In Step 2, the mass ratio of 4-((dimethylamino)methyl)phenol, phthalic anhydride, and p-toluenesulfonic acid catalyst is 2.11 - 2.34 g : 1 - 1.12 g : 0.22 - 0.24 g.

5. The synthesis method of the aromatic acyl chloride according to claim 1, characterized in that, In Step 3, the mass ratio of Intermediate 1 to 3-pentadecylphenoxyethyl bromide is 1.31 - 1.4 g : 2.3 - 2.6 g.

6. The synthetic method of the aromatic acyl chloride according to claim 1, wherein The reaction time in Step 3 is 6 - 8 h.

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