Ethanol → Ethyl 5-amino-3-(2-hydroxyethoxy)-1H-pyrazole-4-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-[(cyano)(ethoxycarbonyl)vinyl]-1,3-dioxolane (2.0 g) in ethanol (20 mL) was added hydrazine hydrochloride (748 mg) and sodium acetate (1.34 g) and the mixture was stirred at 80° C. (external temperature) for 1 hour. After cooling to room temperature, the reaction mixture was filtered through Cerite and the filtrate was concentrated in vacuo. The resultant crude product was purified by a column chromatography on silica gel (solvent; chloroform/methanol=100/0 to 85/15) to give 3-amino-4-ethoxycarbonyl-5-(2-hydroxy)ethoxypyrazole (2.01 g, yield: 86%) as a pale pink solid.

Provenance & Evidence