反应详情

温度

30 °C

To a stirred mixture of compound 16 (10.0 g, 36.3 mmol) and KNO3 (5.51 g, 54.5 mmol) in DCM (1000 mL) was added dropwise 98% H2SO4 (145.4 g, 1.45 mol) at 0° C. The mixture was stirred at 30° C. for 4 days. The H2SO4 layer was then separated and poured into ice-water (50 g) and then extracted with DCM (100 mL×3). The combined organic layers were washed with water, aqueous NaHCO3 solution and brine, then dried over MgSO4 and concentrated in vacuo. The residue was purified via column chromatography on silica gel (Petroleum ether/EtOAc 20:1→10:1→5:1→3:1) to give compound 17 as a yellow solid. 1H NMR (CDCl3; 400 MHz) δ 8.05 (s), δ 7.74 (s), δ 7.61 (s), δ 7.32 (s), δ 5.32 (s), δ 3.91 (s), δ 3.92 (s), δ 1.62 (s), δ 1.59 (s), δ 1.42 (s), δ 1.38 (s).

1. customThe H2SO4 layer was then separated
2. additionpoured into ice-water (50 g)
3. extractionextracted with DCM (100 mL×3)
4. washThe combined organic layers were washed with water, aqueous NaHCO3 solution and brine
5. dry with materialdried over MgSO4
6. concentrationconcentrated in vacuo
7. customThe residue was purified via column chromatography on silica gel (Petroleum ether/EtOAc 20:1→10:1→5:1→3:1)