反应详情

A solution of 3-methylisoquinoline (5.4 g, 0.038 mol) in concentrated sulfuric acid (30 ml) was cautiously added to a solution of potassium nitrate (4.25 g, 1.1 eq) in concentrated sulfuric acid (23 ml) whilst maintaining the temperature below 4° C. (ice bath). Stirring was continued for 2 h and then temperature raised to ambient. Reaction was further stirred for 3 h and then poured into ice-water slurry (500 ml). Neutralisation using solid potassium carbonate afforded a yellow solid which was filtered and washed with water. The crude product was dissolved in ethanol (200 ml), filtered and concentrated under reduced pressure to afford the title compound as a yellow solid.

1. temperaturewhilst maintaining the temperature below 4° C. (ice bath)
2. temperaturetemperature raised to ambient
3. customReaction
4. stirringwas further stirred for 3 h
5. customafforded a yellow solid which
6. filtrationwas filtered
7. washwashed with water
8. dissolutionThe crude product was dissolved in ethanol (200 ml)
9. filtrationfiltered
10. concentrationconcentrated under reduced pressure