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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

3.9 g (0.16 mol) of magnesium are introduced into 8.6 ml of ethanol, and the reaction is started up using 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. in such a manner that the temperature is maintained. The mixture is subsequently stirred for one hour at 60° C. A solution of 31.3 g (0.148 mol) of 3-chloro-2,4-difluorobenzoyl chloride in 16 ml of toluene is then added dropwise at -10° to -5° C., and stirring is continued for one hour at 0° C. and subsequently overnight while the mixture comes to room temperature. The reaction mixture is poured into ice-water, acidified using 10 ml of concentrated sulphuric acid and extracted using toluene. The toluene phase is washed using saturated sodium chloride solution, and the solvent is removed in vacuo.

Herkunft & Nachweise