Tandem Synthesis of 3‑Chloro-4-iodoisoxazoles from 1‑Copper(I) Alkynes, Dichloroformaldoxime, and Molecular Iodine

A tandem synthesis for structurally novel 3-chloro-4-iodoisoxazoles was developed by simply mixing 1-copper­(I) alkynes, dichloro­formaldoxime, and molecular iodine together. The combination of 1-copper­(I) alkyne and molecular iodine was well used as a synthetic equivalent of 1-iodoalkyne without the need for tedious preparation, purification, and storage of 1-iodoalkyne.