Methyl iodide → 4-Bromo-1,3,5-trimethylpyrazole

Reaction equation

[Br:1][C:2]1[C:3]([CH3:8])=[N:4][NH:5][C:6]=1[CH3:7].[H-].[Na+].[H][H].IC.[C:15](=O)([O-])O.[Na+]>CN(C)C=O>[Br:1][C:2]1[C:3]([CH3:8])=[N:4][N:5]([CH3:15])[C:6]=1[CH3:7]

Participants

Reactant 5

HCID 6328Methyl iodide

HCID 24758Sodium hydride

HCID 769374-bromo-3,5-dimethyl-1H-pyrazole

HCID 516892Sodium Bicarbonate

HCID 178418361HCID 178418361, compound

Product 1

HCID 5191814-Bromo-1,3,5-trimethylpyrazole

Reagents, catalysts & solvents 1

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.