反应详情

Under nitrogen, acetic anhydride (25 mL, 265 mmol) was added to a solution of the ketal (11) (4.5 g, 13.06 mmol) in dry pyridine (25 mL, 310 mmol). The reaction was stirred overnight at room temperature in the dark. After that time, methanol (50 mL) was added and solvents removed in vacuo. The treatment with methanol was repeated and the residue obtained crystallized from methanol to give the pure 3-acetate (12) (4.85 g, 96%).

1. customsolvents removed in vacuo
2. customthe residue obtained
3. customcrystallized from methanol