4-Bromo-1-methylpyrazole

4-Bromo-1-methylpyrazole is a colourless or light yellow liquid at room temperature and pressure. It can be used as an intermediate in organic synthesis. It has good solubility in common organic solvents such as ethyl acetate, dichloromethane, dimethyl sulfoxide, and N, N-dimethylformamide but poor solubility in water.

The conventional synthesis method of 4-Bromo-1-methylpyrazole starts from methyl pyrazole and uses NBS to brominate the carbon atom at position 4 in pyrazole using water as a solvent to obtain the target product. This synthetic route is fast and simple, with high yield and convenient post-processing. It is worth noting that the boiling point of this compound is not high, and low-temperature concentration should be paid attention to during post-processing. In addition, there is also a synthetic method using liquid bromine and hydrobromic acid aqueous solution as bromination reagents.