反应详情

5-Aminoisoquinoline-3-carboxylic acid (25 g) is added to methanol (2 liters). The mixture is heated to the reflux temperature and a stream of dry hydrogen chloride is bubbled through for 3 hours. The mixture is heated under reflux for a further 3 hours and then concentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) at 60° C. The residue is dissolved in water (200 cc) and the solution is washed with ethyl acetate (2×100 cc). The aqueous solution is rendered alkaline to pH 9 by adding potassium carbonate. The precipitate formed is filtered off, washed with water and dried to yield 5-amino-3-methoxycarbonylisoquinoline (20.3 g).

1. temperatureThe mixture is heated to the reflux temperature
2. customa stream of dry hydrogen chloride is bubbled through for 3 hours
3. temperatureThe mixture is heated
4. temperatureunder reflux for a further 3 hours
5. concentrationconcentrated to dryness under reduced pressure (20 mm Hg; 2.7 kPa) at 60° C
6. dissolutionThe residue is dissolved in water (200 cc)
7. washthe solution is washed with ethyl acetate (2×100 cc)
8. additionby adding potassium carbonate
9. customThe precipitate formed
10. filtrationis filtered off
11. washwashed with water
12. customdried