Heterothiometallic W(Mo)/S/Cu clusters were developed as novel copper(I) catalysts.
W(Mo)/S/Cu clusters can stabilize copper(I) ions and improve their solubility.
[NH4]2[WS4Cu4I4] is a robust and efficient catalyst for CuAAC reactions.
20">CuAAC reactions were performed under polar solvent or solvent-free conditions.