反应详情

To a solution of 155 (4.0 g, 10 mmol) in methanol (30 mL) was added potassium carbonate (704 mg, 5.1 mmol). The resulting solution was stirred for 2 hours at room temperature, before the reaction was quenched by the addition of water (20 mL), which was then extracted with dichloromethane (3×20 mL). The combined organic layer was washed with brine (2×10 mL), dried over sodium sulfate, filtered and concentrated under vacuum. The crude residue was purified by flash column chromatography with 1%-5% methanol in dichloromethane to afford the title compound as a white solid (2.6 g, 88%). (ES, m/z): [M+H]+ 289.0; 1H NMR (300 MHz, CDCl3) δ 6.34 (d, J=6.0 Hz, 1H), 4.37-4.32 (m, 1H), 4.11-4.05 (m, 1H), 3.94-3.82 (m, 2H), 3.61-3.54 (m, 1H), 3.36-3.23 (m, 1H), 3.08 (s, 6H), 1.46 (s, 6H).

1. customwas quenched by the addition of water (20 mL), which
2. extractionwas then extracted with dichloromethane (3×20 mL)
3. washThe combined organic layer was washed with brine (2×10 mL)
4. dry with materialdried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated under vacuum
7. customThe crude residue was purified by flash column chromatography with 1%-5% methanol in dichloromethane