反应详情

温度

90 °C

Sulfuric acid (200 mL) was heated to 40° C. Then, compound 57 (18.47 g, 32.12 mmol) was added in portions. The mixture was heated to 90° C. and kept at this temperature for 1.5-2 h (TLC monitoring, eluent: CH2Cl2-ethyl acetate, 4:1). The resulting mixture was poured onto ice. The grey precipitate was filtered off, washed on a filter with a mixture of CHCl3-MeOH (4:1). The remaining precipitate (on a filter) was recrystallized with DMF, washed with CH3CN and ether. Yield of pure 58: 2.2 g (14%).

1. additionThe resulting mixture was poured onto ice
2. filtrationThe grey precipitate was filtered off
3. washwashed on
4. filtrationa filter with a mixture of CHCl3-MeOH (4:1)
5. filtrationThe remaining precipitate (on a filter)
6. customwas recrystallized with DMF
7. washwashed with CH3CN and ether