反应详情

HCl gas was bubbled for 30 min through a soln of 20c (800 mg, 2.1 mmol) in EtOAc (10 mL) while the flask was maintained in an ice bath. The resulting solution was subsequently stirred at room temperature for 30 min, and the volatiles were removed under reduced pressure. The white solid thus obtained was recrystallized from 50% isopropyl alcohol-hexanes to provide the hydrochlorides of 21c as a white powder (80%). Elemental analysis: Calc: C=61.12, H=8.1, N=7.5; Fnd: C=59.96, H=Elemental analysis: Gale: C=61.12, H=8.1, N=7.5; Fnd: C=59.96, H=7.95, N=6.86.

1. temperaturewas maintained in an ice bath
2. customthe volatiles were removed under reduced pressure
3. customThe white solid thus obtained
4. customwas recrystallized from 50% isopropyl alcohol-hexanes