反应详情

温度

-20 °C

2-Methyl-1,3-dithiane (1.50 g, 11.2 mmol) was dissolved in THF (50 mL), followed by cooling to −20° C. Then, n-butyllithium (1.58 M solution in hexane, 7 mL, 11.1 mmol) was added dropwise and the mixture was stirred for two hours. Ethyl trifluoroacetate (1.4 mL, 11.8 mmol) was added, and the mixture was heated to room temperature and stirred for 20 hours. Aqueous ammonium chloride solution was added to the reaction solution, followed by extraction with ethyl acetate. Then, the organic layer was washed with brine and dried over anhydrous sodium sulfate. Following concentration under reduced pressure, the residue was purified by silica gel column chromatography (elution solvent: hexane/ethyl acetate=100/0, 95/5, 85/15) to obtain 1.09 g of the title compound as a pale yellow solid (42%).

1. temperaturethe mixture was heated to room temperature
2. stirringstirred for 20 hours
3. extractionfollowed by extraction with ethyl acetate
4. washThen, the organic layer was washed with brine
5. dry with materialdried over anhydrous sodium sulfate
6. concentrationconcentration under reduced pressure
7. customthe residue was purified by silica gel column chromatography (elution solvent: hexane/ethyl acetate=100/0, 95/5, 85/15)