反应详情

To a solution of 4-bromo-benzaldehyde (5 g) and ethyl cyanoacetate (2.9 mL) in toluene (50 mL) was added piperidine (0.046 mL), and the mixture was stirred at reflux for 2 h with a Dean-Stark separator. The mixture was cooled to rt, stirred overnight and toluene was evaporated in vacuo. The crude residue was crystallized from EtOAc to yield the title compound (6.77 g, 90%) as a light yellow solid, MS (EI): m/z=279 ([M]+, 1Br).

1. temperatureat reflux for 2 h with a Dean-Stark separator
2. stirringstirred overnight
3. customtoluene was evaporated in vacuo
4. customThe crude residue was crystallized from EtOAc