Sulfuric Acid → Diethyl (2-chloro-4,5-difluorobenzoyl)propanedioate

Beteiligte Stoffe

Reaktionsschritte

To 6.34 g of magnesium turnings, 13 cc of absolute ethanol and 1.2 ml of carbon tetrachloride were added, and the mixture was stirred. After the initiation of the reaction, a solution comprising 39.9 g of diethyl malonate, 22 cc of absolute ethanol and 75 cc of toluene was dropwise added thereto at a temperature of from 50° to 70° C. After the dropwise addition, the mixture was stirred for two hours. Then, the reaction solution was cooled to -10° to -5° C., and a solution comprising 50 g of 2-chloro-4,5-difluorobenzoyl chloride and 15 ml of toluene was dropwise added thereto. Then, the mixture was stirred for two hours. A dilute sulfuric acid aqueous solution cooled with ice was added thereto, and the content was dissolved, subjected to phase separation and extracted three times with 60 cc of toluene. The organic phase was washed with water, then dried over anhydrous magnesium sulfate and concentrated to obtain 79.2 g of the desired product as a slightly yellow oily substance.

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