Modular Synthesis of Fully Substituted 5-Allyl-Triazoles via a Copper(I)-Catalyzed Interrupted Click/Allylation Cascade Reaction

A series of fully substituted 5-allyl-1,2,3-triazoles was prepared via a copper(I)-catalyzed click/allylation cascade reaction of various alkynes, azides, and allyl bromides. The key step in this process is the interception of the in situ-formed cuprate-triazole intermediate with allyl bromide. Furthermore, this reaction offers an effective strategy for the generation of fully substituted triazoles, involving the formation of C(sp2)-C(sp3) bonds in high yields with complete regioselectivity under mild reaction conditions.