反应详情

温度

0 °C

To a solution containing 6.3 g of 3-benzyl-2,4-pentanedione in 50 ml of dichloromethane was gradually added 5.3 g of bromine in 20 ml of dichloromethane under cooling (0°-5° C.). The solution was stirred for 10 min. at 0° C. and the solvent evaporated in vacuo. The residue was dissolved in 100 ml of pyridine and refluxed for 30 min. Pyridine was evaporated in vacuo, the residue was dissolved in dichloromethane and washed first with 6M hydrochloric acid and then with 2.6M NaOH. The solvent was evaporated and the residue distilled in vacuo. Bp 186°-188° C./16 mm, yield 1.2 g.

1. temperatureunder cooling (0°-5° C.)
2. customthe solvent evaporated in vacuo
3. dissolutionThe residue was dissolved in 100 ml of pyridine
4. temperaturerefluxed for 30 min
5. customPyridine was evaporated in vacuo
6. dissolutionthe residue was dissolved in dichloromethane
7. washwashed first with 6M hydrochloric acid
8. customThe solvent was evaporated
9. distillationthe residue distilled in vacuo