One-pot three-component synthesis of 1,4,5-trisubstituted 5-iodo-1,2,3-triazoles from 1-copper(i) alkyne, azide and molecular iodine

Abstract

Copper(I)-catalyzed cycloaddition of 1-iodoalkyne and azide has proven to be the most efficient method for the synthesis of 1,4,5-trisubstituted 5-iodo-1,2,3-triazoles, but pre-made 1-iodoalkyne is required. We find that the combination of 1-copper(I) alkyne and molecular iodine can serve as a synthetic equivalent of 1-iodoalkyne. Thus, the desired 5-iodo-1,2,3-triazole can be synthesized by simply mixing this combination and an azide together without the tedious synthesis of the corresponding 1-iodoalkyne.