反应详情

4 M solution of trifluoroacetic acid in dichloromethane (5.1 mL, 20.78 mmol, 40 eq) was added at 0° C. to 244d) (0.29 g, 0.51 mmol, 1 eq) in dichloromethane (10 mL). The reaction mixture was then stirred for 3 h at room temperature. The solvent was removed under vacuum and the residue was co-distilled twice with dichloromethane, diluted with dichloromethane (50 mL) and washed with saturated potassium carbonate solution (2×20 mL) and brine (20 mL). The organic layer was dried over sodium sulfate, concentrated and finally chromatographed by preparative HPLC. White solid. Yield: 0.200 g (84% by theory)

1. customThe solvent was removed under vacuum
2. additiondiluted with dichloromethane (50 mL)
3. washwashed with saturated potassium carbonate solution (2×20 mL) and brine (20 mL)
4. dry with materialThe organic layer was dried over sodium sulfate
5. concentrationconcentrated
6. customfinally chromatographed by preparative HPLC