Hydrazine hydrate (1:1) → N-(4-chloro-2-(1-cyclopropylethylcarbamoyl)phenyl)-5-oxopyrazolidine-3-carboxamide

Participants

Reaction Steps

3.58 g of hydrazine monohydrate was dropwise added to a mixed liquid comprising 25 g of methyl 4-(4-chloro-2-(1-cyclopropylethylcarbamoyl)phenylamino)-4-oxoisocrotonate and 250 ml of ethanol, followed by reflux with heating. After stirring for 5.5 hours, the reaction liquid was stood to cool. The precipitated crystals were subjected to suction filtration. The crystals collected after the filtration were washed with ethyl acetate and then with hexane and air dried to obtain 13 g of the desired product.

Provenance & Evidence