反应详情

温度

60 °C

1.25 g (0.05 mol) of sodium hydride (2.5 g of a 50% commercial suspension in paraffin, previously washed twice with benzene) are suspended in 50 ml of anhydrous N,N-dimethylformamide. A solution of 4.95 g (0.05 mol) of 2-piperidinone in 20 ml of N,N-dimethylformamide is added dropwise to the suspension. The mixture is then heated to 60° C. until no more gas is evolved, whereafter it is cooled. A solution of 8.25 g (0.05 mol) of 3-bromodihydro-2(3H)-furanone in 20 ml of anhydrous N,N-dimethylformamide is added dropwise while keeping the temperature at 5° to 10° C. The mixture is then stirred at 60° C. for 5 hours. N,N-Dimethylformamide is evaporated off under reduced pressure. The residue is taken up in chloroform and the insoluble matter filtered off on Norit. The filtrate is again evaporated and 9.8 g of a heavy syrup are obtained. Mass spectrum: M+. at 183 m/e.

1. temperatureis cooled
2. customat 5° to 10° C
3. customN,N-Dimethylformamide is evaporated off under reduced pressure
4. filtrationthe insoluble matter filtered off on Norit
5. customThe filtrate is again evaporated