Hydrochloric Acid → Ethyl 3-(3-chloro-2,4,5-trifluorophenyl)-3-oxopropanoate

Participants

Reaction Conditions

Reaction Steps

To a mixture of 2.64 g (20 mmol) of malonic acid monoethyl ester, 0.10 g (catalytic amount) of dipyridyl, and 50 ml of dry tetrahydrofuran at -30° C. is added 13 ml of n-butyllithium (1.55 M, 20.2 mmol) at a rapid rate. When addition is complete, the solution is warmed to -5° C., and another 13 ml of n-butyllithium (1.55 M, 20.2 mmol) is added dropwise until a pale pink color persists for ten minutes. The suspension is then cooled to -78° C. To this mixture is added a solution of 2.3 g (10 mmol) of 3-chloro-2,4,5-trifluorobenzoyl chloride in 3 ml of dry tetrahydrofuran. The reaction mixture is stirred at -78° C. for one hour, then warmed to -35° C. and poured into a mixture of ice (50 g) and 6 N hydrochloric acid (4 ml). This solution is extracted with dichloromethane, and the extracts are washed with water, 5% aqueous sodium bicarbonate, dilute hydrochloric acid, and water. The organic phase is dried over magnesium sulfate, filtered, and concentrated to give 2.5 g of the title compound as an orange solid.

Provenance & Evidence