反应详情

To a mixture of the product from Step F above (16 g, 51 mmol) in dichloromethane (60 mL) was added trifluoroacetic acid (30 mL) and the resultant solution was stirred at room temperature for 0.5 h. The solution was evaporated under reduced pressure and the residue was dissolved in dichloromethane. The mixture was neutralized by the slow addition of a solution of saturated sodium bicarbonate and the organic layer was removed. The aqueous layer was extracted with four portions of dichloromethane and the combined organic layers were dried over sodium sulfate and concentrated under reduced pressure to afford the title compound. 1H NMR (400 MHz, CDCl3) δ 8.81 (s, 1H), 7.78 (s, 1H), 7.30 (s, 1H), 4.63 (s, 2H), 3.90 (s, 2H).

1. customThe solution was evaporated under reduced pressure
2. dissolutionthe residue was dissolved in dichloromethane
3. additionThe mixture was neutralized by the slow addition of a solution of saturated sodium bicarbonate
4. customthe organic layer was removed
5. extractionThe aqueous layer was extracted with four portions of dichloromethane
6. dry with materialthe combined organic layers were dried over sodium sulfate
7. concentrationconcentrated under reduced pressure