Sodium hydride → Ethyl 3-(p-chlorobenzoyl)-benzyl malonate

Participants

Reaction Steps

A solution of 28 g of ethyl malonate in 28 ml of dimethylformamide was added to a suspension of 8.4 g of sodium hydride in 260 ml of dimethylformamide at a temperature of 10° to 15°C and the temperature was allowed to return to room temperature. After evolution of 3.9 liters of hydrogen, the resulting solution was poured into a suspension of 52.5 g of 3-bromomethyl-4'-chlorobenzophenone (French BSM No. 8440 M) in 400 ml of dimethylformamide at 24°C. The mixture was stirred for 2 hours and was then evaporated to dryness under reduced pressure. The residue was taken up in 500 ml of water and 75 ml of isopropyl ether and the organic phase was decanted. The aqueous phase was extracted with isopropyl ether and the combined organic phases were dried over sodium sulfate, treated with activated carbon, filtered and evaporated to dryness under reduced pressure. The residue was dissolved in 63 ml of isopropyl ether with agitation, was iced and crystallization was started. After being iced overnight, the mixture was vacuum filtered and the precipitate was washed with isopropyl ether. The mother liquors were evaporated to dryness to obtain 48.7 g of ethyl 3-(p-chlorobenzoyl)-benzyl malonate which was used as is for the next step.

Provenance & Evidence