Sodium hydride → HCID 14302346, compound

Participants

Reaction Steps

A 60% dispersion of sodium hydride in mineral oil (12.8 g) was added to tetrahydrofuran (400 ml) and the mixture cooled with stirring using an ice bath. tert-Butyl cyanoacetate (22.8 g) was added dropwise over a 20 minute period with continued ice bath cooling such that the temperature remained below 10° C. 2,3,4,5-Tetrafluorobenzoyl chloride (34 g) was then added dropwise over a one hour period while maintaining the temperature between -5° C. and 0° C. using an ice-acetone bath. The cooling bath was removed and stirring continued for another 30 minutes while the mixture was warmed to room temperature. The mixture was concentrated to dryness under reduced pressure. Water (1.5 liter) and toluene (100 ml) were added with stirring. The layers were separated and the aqueous layer extracted again with toluene (100 ml). The aqueous layer was acidified to pH 1 using 36% hydrochloric acid. The crystals were collected and washed with excess water and dried under vacuum at room temperature to give tert-butyl 2-cyano-3-oxo-3-(2,3,4,5-tetrafluorophenyl)propionate (47 g, 93%), mp 90°-92° C.

Provenance & Evidence