反应详情

3,5-Dimethylanisole (3 g, 22.026 mmol) was initially introduced into methylene chloride (60 ml) and the mixture was cooled, and a solution of chlorosulfuric acid (7.3 ml, 110.13 mmol) in methylene chloride (60 ml) was slowly added dropwise at 0° C. After stirring in a cooling bath for 10 min, the reaction solution was added dropwise to 300 ml of ice-water, the phases were separated, the aqueous phase was extracted with methylene chloride (60 ml) and the combined organic phases were washed with saturated sodium chloride solution (50 ml), dried over sodium sulfate and concentrated in vacuo. During this operation, pentafluorophenol (4.05 g, 22.026 mmol) was dissolved in methylene chloride (50 ml) and triethylamine (6.1 ml, 44.053 mmol) and the solution was stirred for 30 min. The freshly prepared sulfonyl chloride, concentrated on a rotary evaporator, was dissolved in methylene chloride (50 ml) and the solution was slowly added dropwise. After the mixture had been stirred at room temperature for 1 h, saturated sodium bicarbonate solution (40 ml) was added, the phases were separated and the organic phase was washed with saturated sodium chloride solution (40 ml), dried over sodium sulfate and concentrated in vacuo. The crude product was purified by column chromatography (silica gel) with hexane/diethyl ether/methylene chloride (20:1:2). Yield: 6.06 g (71%)

1. temperaturethe mixture was cooled
2. customthe phases were separated
3. extractionthe aqueous phase was extracted with methylene chloride (60 ml)
4. washthe combined organic phases were washed with saturated sodium chloride solution (50 ml)
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated in vacuo
7. concentrationThe freshly prepared sulfonyl chloride, concentrated on a rotary evaporator
8. dissolutionwas dissolved in methylene chloride (50 ml)
9. additionthe solution was slowly added dropwise
10. stirringAfter the mixture had been stirred at room temperature for 1 h
11. additionsaturated sodium bicarbonate solution (40 ml) was added
12. customthe phases were separated
13. washthe organic phase was washed with saturated sodium chloride solution (40 ml)
14. dry with materialdried over sodium sulfate
15. concentrationconcentrated in vacuo
16. customThe crude product was purified by column chromatography (silica gel) with hexane/diethyl ether/methylene chloride (20:1:2)