反应 #2347

反应方程式

sodium carbonate

hydrogen bromide

3-benzylbutyrolactone

ethanol

water

→

ethyl 4-benzyl-3-bromobutyrate

反应条件

后处理

1. 1
   萃取The mixture was extracted with ethyl acetate
2. 2
   其他the organic layer filterd through phase separating paper
3. 3
   其他evaporated

实验过程

A solution of RS 3-benzylbutyrolactone (1.14 g) in ethanol (20 ml) was stirred at 5° C. and gassed for 4 hours with a slow stream of hydrogen bromide. The solution was kept at 5° C. for 20 hours and water (70 ml) added followed by sodium carbonate to neutralise the acid. The mixture was extracted with ethyl acetate and the organic layer filterd through phase separating paper and evaporated to give ethyl 4-benzyl-3-bromobutyrate as an oil; NMR(CDCl3) δ 7.24(5H,m), 4.13(2H,q); 3.45(2H,m), 2.62(2H,d), 2.44(3H,m), 1.25(3H,t); m/e 285(M+H)+.

来源