Ethyl trimethylsilyl malonate → Ethyl 3-[2,4-dichloro-5-(2-chloro-4,6-difluorophenylamino)phenyl]-3-oxopropionate

Participants

Reaction Conditions

Reaction Steps

1.4 ml of a 1.6 M solution of butyllithium in hexane was added to a solution of 3.47 g (17.0 mmol) of ethyl trimethylsilyl malonate in 45 ml of diethyl ether at −75° C. in such a way that the temperature did not rise above −60° C. The mixture was then stirred at −75° C. for 30 minutes. The 2,4-dichloro-5-(2-chloro-4,6-difluorophenylamino)benzoyl chloride was dissolved in 45 ml of dimethoxyethane and added dropwise in 40 minutes. The mixture was slowly warmed to 10° C. and stirred at this temperature for 2.5 hours. The reaction mixture was diluted with ethyl acetate and washed twice each with 250 ml portions of water and saturated sodium bicarbonate solution. The organic phase was dried and concentrated. 3.88 g of the crude mixture were obtained and were reacted without further purification in the next stage.

Provenance & Evidence