反应详情

A solution of the intermediate from step B (8.6 g, 36.5 mmol) in toluene (40 mL), THF (20 mL) and 10% H2SO4 in water (25 mL) was stirred at reflux overnight. After cooling to room temperature, the organic layer was separated, washed with brine, dried over MgSO4 and concentrated. Flash chromatography on silica gel eluting with 5% and then 10% EtOAc in hexanes provided the title compound (6.0 g, 86%) as an oil. MS calculated (M+H)+ 193, found 193.

1. temperatureat reflux overnight
2. customthe organic layer was separated
3. washwashed with brine
4. dry with materialdried over MgSO4
5. concentrationconcentrated