反应详情

A solution of 3E (980 mg, 1.94 mmol) in TFA (2 mL) and CH2Cl2 (2 mL) was stirred at RT for 2 h. After this time, no starting material was detected by LC-MS. The reaction was concentrated under reduced pressure. The resulting residue was diluted with EtOAc (30 mL) and washed with saturated aqueous NaHCO3. The aqueous layer was extracted with EtOAc (30 mL×3). The combined organic layers were washed with saturated NaCl, dried over Na2SO4, filtered and concentrated. The resulting residue was purified by silica gel (40 g) column chromatography eluting with a gradient of EtOAc (30-100%) in hexane to give the title compound as a white solid (470 mg, 65%). LC/MS (method A): retention time=2.72 min, (M+H)+=374.

1. concentrationThe reaction was concentrated under reduced pressure
2. additionThe resulting residue was diluted with EtOAc (30 mL)
3. washwashed with saturated aqueous NaHCO3
4. extractionThe aqueous layer was extracted with EtOAc (30 mL×3)
5. washThe combined organic layers were washed with saturated NaCl
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated
9. customThe resulting residue was purified by silica gel (40 g) column chromatography
10. washeluting with a gradient of EtOAc (30-100%) in hexane