反应详情

To concentrated sulfuric acid (200 ml) at -10° C. was added portionwise 1,2,3,5,6,10b-hexahydropyrrolo[2,1-a]isoquinoline (20.5 g, 118 mmol) over 2 h. After addition was complete, potassium nitrate (1 1.6 g, 0.115 mol) was added portionwise over 3 h. The reaction mixture was stirred for an additional 3 h and then poured onto ice and made basic with concentrated ammonium hydroxide. The product was extracted twice with dichloromethane. The dried (magnesium sulfate) organic phase was concentrated to give a red oil which was immediately dissolved in isopropanol (200 ml) and made acidic with saturated isopropanol-HCl. The resulting precipitate was collected to give a tan solid (18.9 g). Recrystallization from 95% ethanol (100 ml) afforded the title compound as an off-white solid (11.5 g, 62%), m.p. 243-5° C. This was converted to the free base by dissolving in water, making basic with dilute base, and extracting with dichloromethane to give 96% recovery of the product.

1. additionAfter addition
2. additionpoured onto ice
3. extractionThe product was extracted twice with dichloromethane
4. dry with materialThe dried (magnesium sulfate) organic phase
5. concentrationwas concentrated
6. customto give a red oil which
7. customThe resulting precipitate was collected