Triethylamine → ethyl 5-amino-1-ethyl-1H-pyrazole-4-carboxylate

Beteiligte Stoffe

Reaktionsschritte

Triethylamine (19.6 ml, 144 mmol) was added cautiously to a solution of ethyl (ethoxymethylene)cyanoacetate (10.1 g, 60 mmol) and ethyl hydrazine oxalate (9.9 g, 66 mmol) in ethanol (200 ml). The mixture was heated at reflux for 24 h then concentrated in vacuo. The residue was redissolved in EtOAc, washed with 5% KHCO3 solution then brine, dried and concentrated in vacuo. The residue was purified by flash chromatography on silica gel (eluant; 25% pet. ether:75% EtOAc) to yield the title compound (8.8 g, 80%).

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