Sulfuric Acid → Diethyl (3-chloro-2,4-difluorobenzoyl)malonate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

3.9 g (0.16 mol) of magnesium are initially introduced into 8.6 ml of ethanol and the reaction is started with carbon tetrachloride. A solution of 23.1 g (0.144 mol) of diethyl malonate in 16.3 ml of ethanol is added dropwise at an internal temperature of 50-60° C. such that this temperature is maintained. The mixture is then subsequently stirred at 60° C. for one hour. Thereafter, a solution of 31.3 g (0.148 mol) of 3-chloro-2,4-difluorobenzoyl chloride in 16 ml of toluene is added dropwise at -10 to -5° C. and the mixture is subsequently stirred at 0° C. for one hour and then overnight, while warming to room temperature. The reaction mixture is poured onto ice-water, acidified with 10 ml of concentrated sulphuric acid and extracted with toluene. The extract is washed with saturated sodium chloride solution and the solvent is removed in vacuo. Crude yield: 49.9 g

Herkunft & Nachweise