反应详情

20 mL of water and 20 mL of concentrated hydrochloric acid were added to the product of Example 38 (2.5 g, 8 mmol), then it was reacted at 80° C. for 17 hours, after that, the reaction solution was concentrated and recrystallized with isopropanol and isopropyl ether to give the target 1.9 g, yield: 90%. The HNMR spectrum data is the same as that in Example 7.

1. customit was reacted at 80° C. for 17 hours
2. concentrationafter that, the reaction solution was concentrated
3. customrecrystallized with isopropanol and isopropyl ether
4. customto give the target 1.9 g, yield: 90%