反应详情

Under nitrogen atmosphere, methanol (678 mL), trimethyl orthoformate (796 g, 7.50 mol), and (±)-10-camphorsulfonic acid [(±)-CSA] (11.6 g, 0.050 mol, 2 mol %) were added to 1-(5-bromo-3-tert-butyl-4-hydroxyphenyl)ethanone (678 g, 2.50 mol), followed by stirring. After stirring for 2.7 hours, N,N-dimethylformamide (1.7 L) was added and this was cooled on ice. Furthermore, methyl iodide (700 g) was added followed by potassium carbonate (518 g), and this was stirred at room temperature. After stirring for 5.5 hours, water (4750 mL) and n-heptane (4750 mL) were added and the solution was separated. The organic layer was washed with water (2370 mL), and then sodium sulfate (120.2 g) was added. After stirring, the mixture was filtered by suction, and rinsed with n-heptane (250 mL). The filtrate was evaporated (50° C.) to obtain 808 g of the subject compound as a brown oily substance (yield: 98%, HPLC purity: 96.8%).

1. stirringAfter stirring for 2.7 hours
2. temperaturethis was cooled on ice
3. stirringthis was stirred at room temperature
4. stirringAfter stirring for 5.5 hours
5. customthe solution was separated
6. washThe organic layer was washed with water (2370 mL)
7. additionsodium sulfate (120.2 g) was added
8. stirringAfter stirring
9. filtrationthe mixture was filtered by suction
10. washrinsed with n-heptane (250 mL)
11. customThe filtrate was evaporated (50° C.)