反应详情

A solution of the ester of Step A (3.9 g, 15.2 mmol) in tetrahydrofuran (50 mL) was treated with 1 N sodium hydroxide (31 mL, 31 mmol) and then heated at reflux overnight. After cooling, the reaction mixture was concentrated in vacuo. The residue was acidified with 2N hydrochloric acid to give a white solid which was collected by filtration and dried under vacuum to provide the title compound (3.4 g, 98.0%) as a white solid, m.p. 250-254° C.

1. temperatureheated
2. temperatureat reflux overnight
3. temperatureAfter cooling
4. concentrationthe reaction mixture was concentrated in vacuo
5. customto give a white solid which
6. filtrationwas collected by filtration
7. customdried under vacuum