Copper(I)-Catalyzed Three-Component Click/Alkynylation: One-Pot Synthesis of 5‑Alkynyl-1,2,3-triazoles

A copper­(I)-catalyzed
tandem CuAAC/alkynylation reaction of various
alkynes, organic azides, and bromoalkynes to provide rapid access
to 5-alkynyl-1,2,3-triazoles has been developed. The reaction proceeded
via a copper-catalyzed alkyne azide cycloaddition followed by interception
of the in situ formed cuprate–triazole intermediate with bromoalkyne.
This reaction offers a new method to afford fully substituted triazoles
in high yields with complete regioselectivity under mild reaction
conditions.