反应详情

30 g (0.26 mol) of indole were dissolved in a solution of potassium hydroxide (77.6 g, 1.38 mol) in methanol (692 ml). 4-piperidone monohydrate hydrochloride (102.3 g, 0.66 mol) was added in one portion and the mixture was heated to reflux for 5 h. Potassium chloride precipitated upon cooling at room temperature and it was filtered off. The liquid phase was concentrated until only one third of the liquid remained in the round-bottom flask. The solid formed during the concentration of the liquid phase was filtered and washed thoroughly with ethanol and, finally, with ethyl ether. 31.9 g (63% of yield) of the final product were obtained.

1. temperaturethe mixture was heated
2. temperatureto reflux for 5 h
3. customPotassium chloride precipitated
4. filtrationit was filtered off
5. concentrationThe liquid phase was concentrated until only one third of the liquid
6. customThe solid formed during the concentration of the liquid phase
7. filtrationwas filtered
8. washwashed thoroughly with ethanol