反应详情

To a solution of Example 249A (7.4 g, 26.0 mmol) in CH2Cl2 (20 mL) was added trifluoroacetic acid (20.0 mL, 260 mmol) slowly at 0° C. The reaction mixture was stirred at room temperature for 3 hours, and then concentrated under vacuum. The residue was diluted with ethyl acetate (100 mL) and neutralized with saturated aqueous NaHCO3 solution. The layers were separated and the aqueous phase was extracted with ethyl acetate (5×100 mL). The combined organic extracts were dried (Na2SO4), filtered and concentrated to afford the title compound. MS (ESI+) m/z 185 (M+H)+

1. concentrationconcentrated under vacuum
2. additionThe residue was diluted with ethyl acetate (100 mL)
3. customThe layers were separated
4. extractionthe aqueous phase was extracted with ethyl acetate (5×100 mL)
5. dry with materialThe combined organic extracts were dried (Na2SO4)
6. filtrationfiltered
7. concentrationconcentrated