A simple, efficient thermally promoted protocol for Huisgen-click reaction catalyzed by CuSO4·5H2O in water

A thermally promoted and CuSO4-catalyzed new version of the Huisgen-click reaction is presented in this Letter. Notably, this protocol was suitable not only for the reactions between organic azides and alkynes, but also for one-pot three-component reactions among alkyl halides, NaN3, and alkynes.