Copper(I)-Catalyzed Three-Component Click/Alkynylation: One-Pot Synthesis of 5-Alkynyl-1,2,3-triazoles
Weiguo Wang1, Fang Wei1, Yudao Ma1
1Key Lab for Colloid and Interface Chemistry of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University , Jinan 250100, PR China.
Abstract:
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.
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