反应详情

To a solution of the product from Step C (1.30 g, 4.50 mmol) and triethylamine (1.36 g, 13.5 mmol) in anhydrous THF (30 mL) at ambient temperature was added methanesulfonic anhydride (1.18 g, 6.75 mmol). After stirring for 30 min, morpholine (5 mL) was added; this mixture was stirred at ambient temperature for 18 h and then heated at reflux for 1 h. The volatiles were evaporated and a saturated aqueous solution of sodium bicarbonate (100 mL) was added. The mixture was extracted with ethyl acetate (2×100 mL) and the combined extracts were dried (MgSO4) and evaporated to give a viscous oil which was purified by column chromatography (silica, 30 to 50% ethyl acetate/hexane) to give a viscous oil (1.51 g, 94%).

1. stirringthis mixture was stirred at ambient temperature for 18 h
2. temperatureheated
3. temperatureat reflux for 1 h
4. customThe volatiles were evaporated
5. additiona saturated aqueous solution of sodium bicarbonate (100 mL) was added
6. extractionThe mixture was extracted with ethyl acetate (2×100 mL)
7. dry with materialthe combined extracts were dried (MgSO4)
8. customevaporated
9. customto give a viscous oil which
10. customwas purified by column chromatography (silica, 30 to 50% ethyl acetate/hexane)