Reaction #2898

Reaction equation

iodomethane

4-Bromo-3,5-dimethylpyrazole

sodium hydride

sodium hydrogen carbonate

hydrogen

→

title compound

4-Bromo-1,3,5-trimethylpyrazole

Solvents

dimethylformamide

dimethylformamide

Conditions

Workup

1. 1
   workup.ADDITIONwas added
2. 2
   Otherevaporation under high vacuum
3. 3
   Otherthe residue was purified by column chromatography

Procedure

4-Bromo-3,5-dimethylpyrazole (10 g) in dry dimethylformamide (50 ml) was added to a stirred suspension of sodium hydride (1.8 g) in dry dimethylformamide at 0° C. When the evolution of hydrogen was complete, iodomethane (8.9 g) was added dropwise. The mixture was allowed to warm to room temperature and after 30 minutes saturated aqueous sodium hydrogen carbonate (5 ml) was added. Following evaporation under high vacuum, the residue was purified by column chromatography to give the title compound.

Source