Allyl-Assisted, Cu(I)-Catalyzed Azide-Alkyne Cycloaddition/Allylation Reaction: Assembly of the [1,2,3]Triazolo-4,5,6,7-tetrahydropyridine Core Structure.

We report a Cu(I)-catalyzed azide-alkyne-allyl halide three-component reaction for a one-pot synthesis of 1,4-disubstituted 5-allyl-1,2,3-triazoles. The allyl moiety provides not only the electrophile but also a coordinating ligand to Cu, which is essential for the reaction to occur under mild conditions. A concise synthesis of a potential drug candidate 1 is realized based on this key reaction.