Iron oxide modified with pyridyl‐triazole ligand for stabilization of gold nanoparticles: An efficient heterogeneous catalyst for A3 coupling reaction in water

Fe₃O₄ nanoparticles were modified with pyridyl‐triazole ligand and the new magnetic solid was applied for the stabilization of very small and uniform gold nanoparticles. The resulting magnetic material, Fe₃O₄@PT@Au, was characterized using various methods. These gold nanoparticles on a magnetic support were applied as an efficient heterogeneous catalyst for the three‐component reaction of amines, aldehydes and alkynes (A³ coupling) in neat water with 0.01 mol% Au loading. Using magnetic separation, this catalyst could be recycled for seven consecutive runs with very small decrease in activity. Characterization of the reused catalyst did not show appreciable structural modification.