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

Temperature

-5 °C

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.

1. additionWhen addition
2. temperatureThe suspension is then cooled to -78° C
3. temperaturewarmed to -35° C.
4. extractionThis solution is extracted with dichloromethane
5. washthe extracts are washed with water, 5% aqueous sodium bicarbonate, dilute hydrochloric acid, and water
6. dry with materialThe organic phase is dried over magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated

ORD record

ord-53e3acdcb7bd42348d5f3e1ae186d821

Source dataset

uspto-grants-1989_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04885386