3-Chloro-2-hydrazinylpyridine → methyl 1-(3-chloropyridin-2-yl)-5-hydroxy-3-(hydroxymethyl)-4,5-dihydro-1H-pyrazole-5-carboxylate

Participants

Reaction Conditions

Reaction Steps

The mixture of methyl 3-(2,2-dimethyl-1,3-dioxolan-4-ylidene)-2-oxopropanoate (20 g, 0.1 mol) and 2-hydrazino-3-chloropyridine (14.3 g, 0.1 mol) in 40 ml of isopropanol was stirred for 18 hours at 35° C. The precipitate was filtered off and washed with 15 ml of isopropanol. This gave 24.2 g (85%) of the product as a pale yellow solid with a melting point of 113° C.

Provenance & Evidence