Triethylamine → 3-(1-ethyl-5-oxo-2,5-dihydro-1H-pyrazol-3-yl)benzonitrile

Participants

Reaction Conditions

Reaction Steps

Ethyl hydrazine oxalate (15.6 g, 104 mmol, 1.50 equiv) was added to a solution of ethyl 3-(3-cyanophenyl)-3-oxopropanoate (15.0 g, 69.1 mmol, 1 equiv) and triethylamine (14.4 mL, 104 mmol, 1.50 equiv) in ethanol (345 mL). The reaction mixture was heated to 80° C. for 70 min, then was removed from heat an concentrated to ˜¼ volume by rotary evaporation. The residue was partitioned between ethyl acetate and water. The organic layer was washed with saturated aqueous sodium chloride solution, and the washed solution was dried over sodium sulfate. The dried solution was filtered, and the filtrate was concentrated to afford 3-(1-ethyl-5-oxo-2,5-dihydro-1H-pyrazol-3-yl)benzonitrile as a light-yellow solid (18.1 g) of sufficient purity to use in the next step without further purification. Calcd (M+1)+: 214.1. Found: 214.1.

Provenance & Evidence