Sodium hydride → HCID 67755178, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 4.75 g of ethyl 3-amino-4,4,4-trifluorocrotonate in 50 ml of anhydrous toluene was added dropwise to a solution prepared by suspending 1.14 g of sodium hydride (purity: 55%) in 110 ml of dimethylformamide. Said dropwise addition was conducted at 0° C. under stirring over a period of 15 minutes. The resulting mixture was further stirred at 0° C. for 15 minutes. Then the reaction mixture was cooled to -30° C., and a solution of 6.9 g of 4-chloro-2-fluoro-5-methoxycarbonylmethylthiophenyl isocyanate in 50 ml of anhydrous toluene was added dropwise thereto. The resulting reaction mixture was returned to room temperature and stirred for 2 hours. After distilling off the solvent, the residual solution was added with ethyl acetate, washed twice with a solution of 20 ml of 2N hydrochloric acid and 500 ml of water, washed with a saturated sodium chloride aqueous solution, and dried over anhydrous sodium sulfate, and then ethyl acetate was distilled off to obtain a crude product. This crude product was preliminarily purified by silica gel column chromatography using CHCl3 as developing solvent and then purified by silica gel column chromatography using ethyl acetate/hexane (3:1) as developing solvent to obtain 1.5 g of the objective compound as viscous oil.

Provenance & Evidence