Green bio‐based synthesis of Fe₂O₃@SiO₂‐IL/Ag hollow spheres and their catalytic utility for ultrasonic‐assisted synthesis of propargylamines and benzo[b]furans

A novel magnetic hybrid system containing nano‐magnetic Fe 2 O 3 hollow spheres, silica shell, [pmim]Cl ionic liquid and silver nanoparticles was synthesized and characterized. The silver nanoparticles were prepared via biosynthesis using Achillea millefolium flower as reducing and stabilizing agent. The hybrid system was successfully used as an efficient and reusable catalyst for promoting green ultrasonic‐assisted A 3 and KA 2 coupling...