One-Pot Synthesis of Polycyclic Spirooxindoles via Montmorillonite K10-Catalyzed C–H Functionalization of Cyclic Amines

A method for pot and atom economic synthesis of polycyclic spirooxindoles through α-C–H functionalization of cyclic amines has been developed. This highly efficient three-component [3+2] cycloaddition reaction was catalyzed by recyclable montmorillonite K10 and only water was produced as a byproduct.