A copper(I) isonitrile complex as a heterogeneous catalyst for azide-alkyne cycloaddition in water.

A structurally well-defined copper(I) isonitrile complex is shown to be an efficient, heterogeneous catalyst for the Huisgen azide-alkyne 1,3-dipolar cycloaddition under mild conditions in water. Notably, this catalyst can also be utilized in a three-component reaction of halides, sodium azide and alkynes to form 1,4-disubstituted 1,2,3-triazoles in high yields. Furthermore, it can be readily recovered by precipitation and filtration and recycled for at least five runs without significant loss of activity.