反应详情

A mixture of Fe powder (2.38 g, 42.5 mmol), NH4Cl (2.27 g, 42.5 mmol) and (R)-2,2-dimethyl-4-((3-nitrophenoxy)methyl)-1,3-dioxolane 104 (1.80 g, 7.09 mmol) in isopropanol (30 mL)/H2O (10 mL) was heated at reflux for 18 h. The crude material was filtered through a pad of Celite and the filtrate was concentrated under reduced pressure. The resulting aqueous layer was extracted with dichloromethane (3×15 mL). The combined organic layers were dried with Na2SO4, and concentrated under reduced pressure to afford 105 (1.25 g, 76% yield). The acetonide protecting group could be removed after coupling with the appropriate aniline by treatment with EtOH/3 N HCl (4:1) at reflux for 12 h.

1. temperaturewas heated
2. temperatureat reflux for 18 h
3. filtrationThe crude material was filtered through a pad of Celite
4. concentrationthe filtrate was concentrated under reduced pressure
5. extractionThe resulting aqueous layer was extracted with dichloromethane (3×15 mL)
6. dry with materialThe combined organic layers were dried with Na2SO4
7. concentrationconcentrated under reduced pressure