Ethyl chloroformate → HCID 19791291, compound

Participants

Reaction Steps

Sodium hydride (240 mg, 6.00 mmol as a 60 percent slurry in mineral oil) was extracted 3 times with 2 mL portions of dry hexane under an inert atmosphere and then 15 mL of tetrahydrofuran was added and the mixture cooled by stirring in an ice bath. 4-(5-Chloro-2-pyridinyl)-4,5-dihydro-3-(4-fluorophenyl)-N-(4-trifluoromethoxyphenyl)-1H-pyrazole-1-carboxamide (958 mg, 2.00 mmol) was then added in one portion and the mixture allowed to react for 30 min. Ethyl chloro-formate (0.573 mL, 6.00 mmol) was then added with cooling and stirring and the mixture allowed to react at 0°-10° C. for 30 min. The resulting mixture was partitioned between saturated aqueous ammonium chloride and ether. The ethereal phase was dried over magnesium sulfate, and then concentrated by evaporation under reduced pressure. The residue was triturated with 20 mL of ether, refrigerated for about 1 hr, and then recovered by filtration. It was then recrystallized from a mixture of hexane and acetone to obtain 660 mg of the title compound as white crystals melting at 159.5°-161° C. (60 percent yield)

Provenance & Evidence