694-31-5

1,5-Dimethylpyrazole is widely used in food, health products, cosmetics and other fields.

Researchers have reported the alkylation of 3(5)-methylpyrazole with methyl iodide and dimethylcarbonate. However, these methods employ expensive reagents and low yields, and the technology is complex. For practical purposes, a better option is to use dimethylsulfate (DMS) in an alkaline medium as the alkylation agent. Isomers of 1,3-dimethylpyrazole and 1,5-dimethylpyrazole are obtained in a 20% aqueous solution of NaOH at 70°C. The yield of the 60 : 40 mixture of the isomers1,3-dimethylpyrazole and 1,5-dimethylpyrazole is 85%[1].

[1] V. V. Rusak. “Extracting 1,3-dimethylpyrazole and 1,5-dimethylpyrazole from binary industrial mixtures.” Coke and Chemistry 58 7 (2015): 275–278.