Cu-Catalyzed Site-Selective and Enantioselective Ring Opening of Cyclic Diaryliodoniums with 1,2,3-Triazoles.

A Cu-catalyzed enantioselective ring-opening/triazolylation reaction is reported. The reaction shows excellent chemoselectivity regarding the three different nitrogen atoms of 1,2,3-triazoles. The optically enriched axially chiral aryl iodides thus obtained were readily derivatized to different types of chiral phosphine ligands and their corresponding copper or palladium complexes.