Hydrazine hydrate (1:1) → 3-(3,4-dimethoxyphenyl)-4,4-dimethyl-1H-pyrazol-5(4H)-one

Participants

Reaction Steps

192 g of methyl 3-(3,4-dimethoxyphenyl)-2,2-dimethyl-3-oxopropanoate (compound D1) is dissolved in 600 ml of ethanol, 145 ml hydrazine hydrate is added and the mixture is heated under reflux for 17 h. The mixture is concentrated in vacuo, resuspended in 400 ml of ethanol and concentrated again. The solids are refluxed for 60 min in 400 ml of ethanol, cooled to RT and filtered. The product is washed with 50 ml of ethanol followed by 100 ml of diethyl ether and dried in vacuo at 50° C.

Provenance & Evidence