Preparation method of bis (4-tert-butylphenyl) iodonium trifluoromethane sulfonate

Abstract

The invention belongs to the technical field of organic chemistry, and particularly relates to a preparation method of bis (4-tert-butylphenyl) iodonium trifluoromethane sulfonate, which comprises the following steps: by taking tert-butylbenzene as an initial raw material, carrying out substitution reaction with potassium iodate and concentrated sulfuric acid, and then carrying out ion exchange with potassium trifluoromethane sulfonate, thereby obtaining the bis (4-tert-butylphenyl) iodonium trifluoromethane sulfonate. The bis (4-tert-butylphenyl) iodonium trifluoromethane sulfonate is obtained; the process steps are simple, and the prepared bis (4-tert-butylphenyl) iodonium trifluoromethane sulfonate product is high in purity, high in yield and suitable for industrial application.

Description

Technical Field

[0001] The invention belongs to the technical field of organic chemistry, and particularly relates to a method for preparing bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate. Background Art

[0002] As a new type of photoacid generator monomer, bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate has shown wide application potential in optoelectronic materials and other fields. Its high-purity product has high thermal stability, specific absorption wavelength and stable acid generation performance, which is very suitable for the synthesis of optoelectronic materials and has professional applications in the field of high-end chemical industry.

[0003] However, the methods for preparing this compound in the prior art have many challenges, such as the violent exothermic reaction process using benzene and iodine sulfate as raw materials, the large number of isomers, the high price of iodine sulfate and the unsuitability for industrial production.

[0004] Therefore, the current problem that needs to be solved is how to prepare high-yield, high-purity bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate with low cost and simple process. This requires in-depth study of the reaction mechanism, optimization of the reaction path, selection of suitable catalysts and solvents, and attention to the application of green chemistry and sustainable development concepts. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for preparing bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate. Tert-butylbenzene is used as a starting material, and a substitution reaction is carried out with potassium iodate and concentrated sulfuric acid, and then ion exchange is carried out with potassium trifluoromethanesulfonate to obtain bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate. The process steps of the present invention are simple, and the prepared bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate product has high purity and high yield, thereby meeting the current industrial demand for high-purity bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate.

[0006] The technical solution of the present invention is:

[0007] A method for preparing bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate, wherein the overall reaction formula of the preparation method is as follows:

[0008]

[0009] Specifically, the preparation method of bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate provided by the present invention mainly comprises the following steps:

[0010] S1. Add potassium iodate, acetic anhydride and acetic acid to a three-necked flask, slowly add concentrated sulfuric acid at 0-10°C while stirring, stir for 30 minutes after the addition is complete, then continue to add tert-butyltoluene to the material in the three-necked flask, and keep the reaction warm for 10 hours;

[0011] Afterwards, 20 mL of water was added to quench the reaction, the aqueous phase was separated, and the aqueous phase was extracted with benzene 2-3 times. The extracted aqueous phase was cooled to room temperature, crystallized, and filtered to obtain a white powder intermediate Ⅰ;

[0012] S2. Take the intermediate I obtained in S1 and water in a flask, stir under nitrogen protection, heat and keep warm to dissolve, then add the sodium chloride solution dropwise to the material in the flask while stirring, continue stirring for 2 hours after the addition is completed, filter and obtain a white solid;

[0013] Add an alcohol solvent to the white solid and heat it to 50-100°C to dissolve it and then cool it down to crystallize to obtain a white powder intermediate II;

[0014] S3. Add intermediate II obtained in S2 and methanol into a flask, stir, raise the temperature to 60°C and keep under reflux, add potassium trifluoromethanesulfonate aqueous solution dropwise, then cool to room temperature and react for 2h;

[0015] After the reaction is completed, the precipitate is filtered off, methyl tert-butyl ether is added to the filtrate, and the mixture is filtered off and dried in vacuo to obtain the white target product, bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate.

[0016] Among them, the substitution reaction of S1 is carried out at a low temperature of 0 to 10°C. After investigation, it was found that too high a temperature will increase the impurities. Therefore, the reaction temperature needs to be controlled at 0 to 10°C, which not only avoids the increase in cost caused by the temperature increase, but also can obtain good reaction effects.

[0017] Preferably, in S1, the molar ratio of tert-butyltoluene: potassium iodate: acetic anhydride: acetic acid: concentrated sulfuric acid is 1: 1.5-1.7: 1.3-1.5: 2.1-2.5: 0.7-0.9.

[0018] Preferably, in S2, the mass ratio of intermediate I to water is 1:5; the concentration of sodium chloride solution is 40wt%; the mass ratio of intermediate I: sodium chloride solution is 1:1.5; and the vacuum degree during filtration is 0.05MPa.

[0019] Preferably, in S2, the alcohol solvent is methanol, and the mass ratio of the white solid to the alcohol solvent is 1:2.1-5.0.

[0020] Preferably, in S3, the mass fraction of the potassium trifluoromethanesulfonate aqueous solution is 99%; the molar ratio of intermediate II to potassium trifluoromethanesulfonate is 1:1.0-1.3; and the mass ratio of intermediate II to methanol is 1:10.0-16.0.

[0021] The invention involves using tert-butyltoluene as a starting material, chemically reacting the tert-butyltoluene with potassium iodate and concentrated sulfuric acid, and then performing an ion exchange reaction to finally generate the target product bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate.

[0022] Compared with the prior art, the present invention has the following advantages and effects:

[0023] (1) The yield of bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate prepared by the preparation method of the present invention is high, the yield of each step of the reaction is more than 80%, and the final yield is also greater than 80%, which is 15 percentage points higher than the total yield of bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate prepared by the prior art; the purity of the final product can reach 99.7%, which meets the current demand for high-purity bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate;

[0024] (2) The present invention uses tert-butylbenzene as a starting material to prepare high-purity bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate, which provides a new idea for the preparation of bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate. In the first step of the substitution reaction, acetic anhydride is used as a dehydrating agent to ensure the reaction efficiency.

[0025] (3) The preparation method provided by the present invention has the advantages that the temperature conditions of the entire reaction process are easy to control, the method is simple and easy to implement, there are few intermediate impurity products, the preparation cost is saved and the purity of the product is improved, and it is suitable for industrial application. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate prepared in Example 1 1 HNMR spectrum;

[0027] Figure 2 The bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate prepared in Example 1 13 CNMR spectrum;

[0028] Figure 3 The bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate prepared in Example 1 19 FNMR spectrum. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the present invention, the present invention is further described in conjunction with specific implementation methods.

[0030] 1.1 Experimental reagents and raw materials

[0031]

[0032]

[0033] Example 1

[0034] A method for preparing bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate, characterized in that the overall reaction formula of the preparation method is as follows:

[0035]

[0036] The preparation method comprises the following steps:

[0037] (1) Substitution reaction

[0038] After adding 6g of potassium iodide, 2.7g of acetic anhydride and 2.5g of acetic acid into a three-necked flask, stir at 0°C, and slowly add 1.8g of concentrated sulfuric acid using a constant pressure dropping funnel. After the addition is complete, stir for 30min, and then continue to add 2.5g of tert-butylbenzene to the reaction system. After complete addition, keep the reaction at 0°C for 10h;

[0039] After the reaction was completed by HPLC, 20 mL of water was added to quench the reaction, the aqueous phase was separated by a separatory funnel, and extracted with benzene 2-3 times. No impurities and raw material residues were detected by HPLC, and the aqueous phase was cooled to 20°C to precipitate crystals to obtain intermediate I, i.e., 3.5 g of bis(4-tert-butylphenyl)iodonium chloride, with a yield of 80.1%.

[0040] (2) Ion exchange reaction

[0041] Add 5g (10.2mmol) of the intermediate I obtained in step (1) and 30g of water to a flask, stir under nitrogen protection, heat and keep warm to dissolve, weigh 0.9g (15.3mmol) of sodium chloride, dissolve in water and then drop into the flask, stir rapidly, and a white solid is generated. After the addition is complete, stir for 2h, filter the resulting reaction solution to obtain a solid, add 20mL of methanol to the resulting solid, heat to 80°C, dissolve, cool and crystallize, and vacuum dry the resulting solid for 12h to obtain 3.6g of intermediate II, with a yield of 84.0%. HPLC detection shows a purity of 99.7%.

[0042] 1 H NMR (400MHz, DMSO) δ8.19-8.12(m,4H),7.59-7.51(m,4H),1.26(s,18H). 13CNMR(101MHz,DMSO)δ155.72(s),135.43(s),129.35(s),113.32(s),35.39(s),31.19(s).

[0043] (3) Ion exchange reaction

[0044] Add 5 g (11.66 mmol) of intermediate II obtained in step (2) and 100 mL of methanol into a flask, stir, heat to 60°C and keep under reflux, add 2.21 g (12.83 mmol) of trifluoromethanesulfonic acid aqueous solution dropwise, cool to room temperature after complete addition, and react for 2 h;

[0045] After the reaction, the precipitate was filtered off, and 150 mL of methyl tert-butyl ether was added to the filtrate to produce a white precipitate. After filtration, the precipitate was vacuum dried at 40° C. to obtain 5.13 g of bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate with a yield of 81.2%. The purity was 99.7% as determined by HPLC.

[0046] It was determined that the yield of the first step substitution reaction was 80.1%, the yield of the second step ion exchange reaction was 84.0%, and the yield of the third step ion exchange reaction was 81.2%.

[0047] like Figure 1 , Figure 2 , Figure 3 As shown, the structural information of bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate obtained in this example is as follows:

[0048] 1 H NMR (400MHz, DMSO) δ8.19-8.13(m,4H),7.58-7.52(m,4H),1.26(s,18H). 13 CNMR(101MHz,DMSO)δ155.72(s),135.44(s),129.35(s),113.32(s),35.39(s),31.20(s). 19 FNMR (376MHz, DMSO) δ-77.73 (s).

[0049] Example 2

[0050] A method for preparing bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate, the method comprising the following steps:

[0051] (1) Substitution reaction

[0052] Add 6g potassium iodide, 2.7g acetic anhydride, 1.8g concentrated sulfuric acid and 2.5g acetic acid into a three-necked flask, stir at room temperature for 30min, and add 2.5g tert-butylbenzene to the reaction system using a constant pressure dropping funnel. After the addition is complete, keep the reaction warm for 10h.

[0053] After the reaction was completed by HPLC, 20 mL of water was added to quench the reaction, the aqueous phase was separated by a separatory funnel, and extracted with dichloromethane three times. HPLC detected that there were no impurities and raw material residues, and the aqueous phase was cooled to precipitate crystals to obtain 3.2 g of off-white powder intermediate I with a yield of 74.4%. The chemical structure was confirmed by H NMR spectrum, which was consistent with Example 1 (1).

[0054] (2) Ion exchange reaction

[0055] Add 5 g (10.2 mol) of the intermediate I obtained in step (1) and 60 g of water into a flask and stir at 60°C until completely dissolved. Weigh 0.9 g (15.3 mmol) of sodium chloride, dissolve it in water and add it dropwise to the intermediate I while introducing nitrogen protection. The reaction temperature is gradually raised to 100°C, kept at 100°C and stirred for 2 hours, cooled and crystallized, and the precipitated solid is filtered. 35 mL of anhydrous methanol is added to the solid, the temperature is raised to 60°C to dissolve, and then the temperature is slowly lowered for recrystallization. The precipitated solid is filtered and dried to obtain 3.5 g of white powder intermediate II with a yield of 82%. The chemical structure is confirmed by H NMR spectrum, which is consistent with Example 1 (2).

[0056] (3) Ion exchange reaction

[0057] Add 5g (11.66mmol) of the intermediate II obtained in step (2), 10mL of 100mL of water, 60mL of methanol, and dropwise add 2.19g (11.66mmol) of trifluoromethanesulfonic acid aqueous solution into a flask. Then heat to reflux, stir for 5 hours under reflux, cool to 0°C, a white solid precipitates, filter the precipitate, add 150mL of methyl tert-butyl ether to the filtrate, produce a white precipitate, filter and vacuum dry at 40°C, and obtain 5.1g of a white solid, with a yield of 81.2%. The chemical structure is confirmed by H NMR, which is consistent with Example 1 (3).

[0058] In summary, the preparation method of bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate provided by the present invention optimizes the reaction steps, so that the temperature of the entire preparation process is easy to control, the method is simple, the impurities are small, the cost is reduced, the purity is improved, and it is very suitable for industrial application.

[0059] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent changes and modifications made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A method for preparing bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate, characterized in that: The preparation method comprises the following steps: S1. Add potassium iodate, acetic anhydride and acetic acid to a three-necked flask, slowly add concentrated sulfuric acid at 0-10°C while stirring, stir for 30 minutes after the addition is complete, then continue to add tert-butyltoluene to the material in the three-necked flask, and keep the reaction warm for 10 hours; Afterwards, 20 mL of water was added to quench the reaction, the aqueous phase was separated, and the aqueous phase was extracted with benzene 2-3 times. The extracted aqueous phase was cooled to room temperature, crystallized, and filtered to obtain a white powder intermediate Ⅰ; S2. Take the intermediate I obtained in S1 and water in a flask, stir under nitrogen protection, heat and keep warm to dissolve, then add the sodium chloride solution dropwise to the material in the flask while stirring, continue stirring for 2 hours after the addition is completed, filter and obtain a white solid; Add an alcohol solvent to the white solid and heat it to 50-100°C to dissolve it and then cool it down to crystallize to obtain a white powder intermediate II; S3. Add intermediate II obtained in S2 and methanol into a flask, stir, raise the temperature to 60°C and keep under reflux, add potassium trifluoromethanesulfonate aqueous solution dropwise, then cool to room temperature and react for 2h; After the reaction is completed, the precipitate is filtered off, methyl tert-butyl ether is added to the filtrate, and the mixture is filtered off and dried in vacuo to obtain the white target product, bis(4-tert-butylphenyl)iodonium trifluoromethanesulfonate.

2. The preparation method according to claim 1, characterized in that The overall reaction formula of the preparation method is as follows: 。 3. The preparation method according to claim 1, characterized in that: In S1, the molar ratio of tert-butyltoluene: potassium iodate: acetic anhydride: acetic acid: concentrated sulfuric acid is 1: 1.5-1.7: 1.3-1.5: 2.1-2.5: 0.7-0.

9.

4. The preparation method according to claim 1, characterized in that: In S2, the mass ratio of intermediate I to water is 1:5; the concentration of sodium chloride solution is 40wt%; the mass ratio of intermediate I: sodium chloride solution is 1:1.5; and the vacuum degree during filtration is 0.05MPa.

5. The preparation method according to claim 1, characterized in that: In S2, the alcohol solvent is methanol, and the mass ratio of the white solid to the alcohol solvent is 1:2.1-3.

0.

6. The preparation method according to claim 1, characterized in that: In S3, the mass fraction of potassium trifluoromethanesulfonate aqueous solution is 99%; the molar ratio of intermediate II to potassium trifluoromethanesulfonate is 1:1.0-1.3; and the mass ratio of intermediate II to methanol is 1:5.1-8.5.

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