Methyl chloroformate → HCID 59355573, compound

Participants

Reaction Steps

5-Bromo-2-(3-chloro-pyridin-2-yl)-2H-pyrazole-3-carboxylic acid [6-chloro-2-(N′-ethyl-hydrazinocarbonyl)-4-methyl-pyridin-3-yl]-amide (10-a) (320 mg) was dissolved in pyridine (4 mL), methyl chloroformate (190 μL) was added and the reaction mixture was stirred at room temperature. After 30 min, 1 h and 1.5 h, methyl chloroformate (each 95 μL) was added. After 1 h stirring at room temperature, the reaction mixture was quenched with water and 3× co-evaporated with toluene. The residue was dissolved in water and ethyl acetate, the layers were separated and the aqueous layer was extracted 2× with ethyl acetate. The combined organic layer was washed with brine, dried over magnesium sulfate and concentrated in vacuum. The residue was purified by column chromatography (silica 60, hexane/ethyl acetate=2:1, Rf=0.10) to afford 308 mg of the title compound (10) of the present invention of the formula

Provenance & Evidence