反应详情

A suspension of the product of step A (0.4 g, 1.6 mmol) and KMnO4 (0.502 g, 3.2 mmol) in dioxane (15 ml) was refluxed for 2 h with stirring. The solution was filtered through silica gel bead and washed with EtOAc (30 ml). The solvent was evaporated to dryness to give the title compound (0.35 g, 81.6%), as white solid. 1H-NMR (CDCl3) 7.30-7.58 (m, 5H); 7.76 (d, 1H, J=8.15 Hz); 8.11 (d, 2H, J=8.03 Hz).

1. temperaturewas refluxed for 2 h
2. filtrationThe solution was filtered through silica gel bead
3. washwashed with EtOAc (30 ml)
4. customThe solvent was evaporated to dryness