Nitrogen → 1-Methyl-1H-pyrazole-3-sulfonyl chloride

The N-methylpyrazole sulfonyl chloride was prepared by adding N-methylpyrazole to chilled (0° C.) chlorosulfonic acid. The reaction mixture was allowed to warm to room temperature and the heated to 100° C. overnight under a stream of N2. The reaction mixture was then cooled to room temperature and chilled to 0° C. To this solution was added thionyl chloride (2.5 eq.) and the reaction was stirred at room temperature for 30 min, then warmed to 70° C. for two hours. The reaction was cooled to room temperature and then chilled in an ice bath. Water and ice were slowly added to the reaction mixture to precipitate a white solid which was collected by filtration. The desired sulfonyl chloride was washed with cold water and hexane. The title compound was prepared using Method 15 and was isolated as a white, hygroscopic solid, mp=>200° C.

1. temperatureThe reaction mixture was then cooled to room temperature
2. temperaturechilled to 0° C
3. temperaturewarmed to 70° C. for two hours
4. temperatureThe reaction was cooled to room temperature
5. temperaturechilled in an ice bath
6. customto precipitate a white solid which
7. filtrationwas collected by filtration
8. washThe desired sulfonyl chloride was washed with cold water and hexane
9. customwas isolated as a white, hygroscopic solid, mp=>200° C.

ORD record

ord-8eae3f22cb7c44bf90c96e2b47a08204

Source dataset

uspto-grants-2002_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06492421B1