Methylhydrazine → HCID 178498595, compound

Participants

Reaction Conditions

Reaction Steps

A diethyl ether solution (35 ml) of dimethyl acetylenedicarboxylate (5.0 g, 35 mmol) was cooled with a freezing medium (salt & ice). To this solution, a diethyl ether solution (15 ml) of methyl hydrazine (0.63 ml, 35 mmol) was added dropwise while maintaining the temperature at 0° C. or less. After completion of dropwise addition, the solution was stirred at 0° C. for one hour. The insoluble matter precipitated was obtained by filtration and washed with diethyl ether. The filter cake was heated to 130° C. for 30 minutes and cooled to room temperature. Methanol was added to the cake, which was concentrated under reduced pressure. Ethyl acetate was added to the obtained residue and the residue was concentrated under reduced pressure. Ethyl acetate was added to the residue and the insoluble matter precipitated was obtained by filtration, washed with ethyl acetate, and dried to obtain methyl 5-hydroxy-1-methyl-1H-pyrazole-3-carboxylate (3.26 g) as light yellow powder.

Provenance & Evidence