反应详情

Diethyl methylmalonate and N,N'-dimethylhydrazine are heated under reflux for 170 hours in methanol in the presence of sodium methylate under an atmosphere of nitrogen. 3-Hydroxy-1,2,4-trimethyl-5-pyrazolone is obtained in the form of colorless crystals which, after recrystallization from ethyl acetate, melt at 87°-89° C.