反応 #51637

反応方程式

acetic anhydride

ketal

17,17-Ethylenedioxy-2-methoxyestra-1,3,5(10)-trien-3-ol

pyridine

→

3-acetate

収率 96.1%

17,17-Ethylenedioxy-2-methoxyestra-1,3,5(10)-trien-3-ol Acetate

収率 96.1%

溶媒

methanol

反応条件

後処理

1. 1
   その他solvents removed in vacuo
2. 2
   その他the residue obtained
3. 3
   その他crystallized from methanol

実験手順

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%).

出典