Réaction #2898

Équation de réaction

iodomethane

4-Bromo-3,5-dimethylpyrazole

sodium hydride

sodium hydrogen carbonate

hydrogen

→

title compound

4-Bromo-1,3,5-trimethylpyrazole

Solvants

dimethylformamide

dimethylformamide

Conditions de réaction

Traitement

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

Mode opératoire

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