Pyridine → HCID 22013556, compound

Participants

Reaction Conditions

Reaction Steps

1.82 g of 3-(3-fluoro-5-chloro-2-pyridyl)-4-methyl-5-carbamoyl-1-methyl-[1H]-pyrazole (Example H44) are suspended in 20 ml of dioxane. First 1.65 ml of pyridine and then 1.44 ml of trifluoroacetic anhydride are added, while cooling in an ice-bath. 5 minutes later, the cooling bath is removed and the mixture is stirred at 22° C. for 1 hour. The brown-red solution is diluted with diethyl ether and washed with one molar hydrochloric acid and then with brine. After drying over sodium sulfate and filtering, the filtrate is concentrated directly together with twice the amount of silica gel. After application of this silica gel to a flash column, the column is eluted with n-hexane/ethyl acetate 4/1. 1.60 g of the desired title compound are obtained as a beige solid of melting point 144-146° C.

Provenance & Evidence