Halogenation of Pyrazoles Using N‐Halosuccinimides in CCl₄ and in Water

Abstract

Reaction of pyrazoles with N‐halosuccinimides (NXS, X=Br, Cl) in either CCl₄ or water gave 4‐halopyrazoles in excellent yields. The reaction was carried out under mild conditions and did not require any catalysts or special precautions. The reaction provides an efficient method for 4‐C halogenation of pyrazoles.

Keywords:

• carbon tetrachloride
• halogenation
• N‐halosuccinimides
• pyrazoles
• water

Acknowledgment

We thank the Natural Science Fund of Anhui Province, China, for financial support.