Triethylamine → 5-nitro-1H-pyrazole-3-carboxylic acid [2-(4-chloro-phenyl)-ethyl]-amide

Participants

Reaction Steps

To a solution of 5-nitro-1H-pyrazole-3-carboxylic acid (200 mg, 1.3 mmol, 1 eq) in tetrahydrofuran (5 mL) were added triethylamine (350 μL, 1.9 mmol, 1.5 eq), hydroxybenzotriazole (HOBT) (257 mg, 1.27 mmol, 1 eq), 2-(4-chloro-phenyl)-ethylamine (180 μL, 1.27 mmol, 1 eq) and EDCI (364 mg, 1.9 mmol, 1.5 eq). The mixture was stirred at room temperature during 20 h. Water (10 mL) was then added and the aqueous phase was extracted with ethyl acetate (2×15 mL). The organic layers were dried over magnesium sulfate, filtered and evaporated in vacuo. The crude residue was purified by flash chromatography using cyclohexane and ethyl acetate (100/0) to (50/50) to afford 5-nitro-1H-pyrazole-3-carboxylic acid [2-(4-chloro-phenyl)-ethyl]-amide as white solid (160 mg, 43% yield).

Provenance & Evidence