反应详情

Acetic acid (56.8 ml) and sulfuric acid (11.8 ml) are added to 1-benzyl-4-cyanomethyl-piperidine-4-carbonitrile (27.2 g, 0.114 mmol) at ambient temperature. The reaction mixture is stirred at 125 C.° for 1 h, cooled down to the room temperature and added to saturated NaOH aq. to adjust to pH 6.0. The mixture is extracted with dichloromethane. The combined extracts are washed with H2O and brine, dried over sodium sulfate and evaporated down to give 8-benzyl-2,8-diaza-spiro[4.5]decane-1,3-dione (three steps yield: 81.8%).

1. extractionThe mixture is extracted with dichloromethane
2. washThe combined extracts are washed with H2O and brine
3. dry with materialdried over sodium sulfate
4. customevaporated down