反应详情

温度

100 °C

To a solution of benzyl crotonate (4.0 g, 22.73 mmol) in anhydrous carbon tetrachloride (20 ml) was added N-bromosuccinimide (4.045 g, 22.7 mmol). The resulting suspension was refluxed at 100° C. under nitrogen for 20 minutes. After cooling to room temperature, the solid was removed by filtration. The filtrate was evaporated under reduced pressure to dryness. The oily residue was separated on a flash column (silica, F 4×40 cm), packed with hexane. The column was eluted with 4 liters of 4% ethyl acetate. The desired product was obtained as an oil (510 mg, 9% yield). Rf: 0.4 (10% ether/hexane) 1H NMR (CDCl3): δppm 3.99 (2H, dd, J1=7.4 Hz, J2=1.3 Hz), 5.19 (2H, s), 6.07 (1H, dt, J1=15.3 Hz, J2=1.1 Hz), 7.04 (1H, m), 7.36 (5H, m). 13C NMR (CDCl3): δppm 29.0 (t), 66.5 (t), 124.2 (d), 128.2 (d), 128.3 (d), 128.5 (d), 135.8 (s), 142.2 (d), 165.2 (s).

1. temperatureAfter cooling to room temperature
2. customthe solid was removed by filtration
3. customThe filtrate was evaporated under reduced pressure to dryness
4. customThe oily residue was separated on a flash column (silica, F 4×40 cm)
5. washThe column was eluted with 4 liters of 4% ethyl acetate