反应详情

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 filtered 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)+.

1. extractionThe mixture was extracted with ethyl acetate
2. filtrationthe organic layer filtered through phase
3. customseparating paper
4. customevaporated