Copper-Catalyzed Huisgen 1,3-Dipolar Cycloaddition under Oxidative Conditions: Polymer-Assisted Assembly of 4‑Acyl-1-Substituted-1,2,3-Triazoles
journal contributionposted on 05.07.2013, 00:00 by Paula M. Diz, Alberto Coelho, Abdelaziz El Maatougui, Jhonny Azuaje, Olga Caamaño, Álvaro Gil, Eddy Sotelo
We herein document the first example of a reliable copper-catalyzed Huisgen 1,3-dipolar cycloaddition under oxidative conditions. The combined use of two polymer-supported reagents (polystyrene-1,5,7-triazabicyclo[4,4,0]dec-5-ene/Cu and polystyrene-2-iodoxybenzamide) overcomes the thermodynamic instability of copper(I) species toward oxidation, enabling the reliable Cu-catalyzed Huisgen 1,3-dipolar cycloadditions in the presence of an oxidant agent. This polymer-assisted pathway, not feasible under conventional homogeneous conditions, provides a direct assembly of 4-acyl-1-substituted-1,2,3-triazoles, contributing to expand the reliability and scope of Cu(I)-catalyzed alkyne–azide cycloaddition.