6134-66-3

141-97-9

6134-66-3

The general procedure for the synthesis of ethyl 2,2-dichloro-3-oxobutanoate from ethyl acetoacetate was as follows: a mixture of 2.5 mmol NH4Cl, 5.0 mmol ethyl acetoacetate and 10.0 mL acetonitrile was stirred for 5 minutes. Subsequently, 7.5 mmol DCDMH was added in five portions over 1 hour and the reaction mixture was stirred at 35°C for 12 hours. After completion of the reaction, the solvent was removed by distillation under reduced pressure. To the residue was added 20 mL of ethyl acetate, followed by washing the ethyl acetate layer twice with water (20 mL) and drying with anhydrous Na2SO4. After drying, the mixture was filtered and the solvent was removed under reduced pressure. Finally, the residue was purified by silica gel column chromatography (eluent ratio of petroleum ether/ethyl acetate=20/1, v/v) to afford the target product ethyl 2,2-dichloro-3-oxobutanoate.