Nitrosylsulfuric acid in the synthesis of 5-chloroisoxazoles from 1,1-dichlorocyclopropanes

R4NHal/NOHSO4: A Usable System for Halogenation of Isoxazoles, Pyrazoles, and Beyond

“…One of the routes for the construction of five-membered N , O -heterocyclic scaffolds, isoxazolines, or isoxazoles is nitrosation of cyclopropanes. − Recently, we have shown that nitrosylsulfuric acid can be successfully used in the synthesis of 3,5-diarylisoxazoles from the corresponding 1,2-diarylcyclopropanes. , We envisioned the scenario depicted in Scheme…”