反应详情

温度

0 °C

To a solution containing 1.94 mmol of the compound obtained in Step 1 in 20 ml of anhydrous dichloromethane, maintained at 0° C. under argon, there are added 9.71 mmol of trifluoroacetic anhydride. After reacting for 3 days at ambient temperature, the reaction mixture is concentrated under reduced pressure. The residue is taken up in a mixture of dichloromethane and aqueous NaHCO3 solution. After extraction with dichloromethane, the combined organic phases are treated in conventional manner. Chromatography of the residue over silica gel (dichloromethane) allows the expected product to be isolated, the latter being subsequently recrystallised from ethyl ether.

1. concentrationthe reaction mixture is concentrated under reduced pressure
2. additionThe residue is taken up in a mixture of dichloromethane and aqueous NaHCO3 solution
3. extractionAfter extraction with dichloromethane
4. additionthe combined organic phases are treated in conventional manner
5. customto be isolated
6. customthe latter being subsequently recrystallised from ethyl ether