Tethering of Cu(II) Schiff base metal complex on mesoporous material MCM-41: catalyst for Ullmann-type coupling reactions

The siloxane-functioned Cu(II) complex derived from 3-aminopropyltrimethoxysilane, terephthaldehyde and 2-aminophenol was anchored on hexagonal mesoporous silica MCM-41. The MCM-41 and its Schiff base MCM-41 complex was characterized by FTIR, small-angle X-ray diffraction, SEM-EDX, N₂ adsorption and desorption analysis and TGA. The synthesized Cu-Schiff base MCM-41 catalyst has been successfully applied as a catalyst for Ullmann-type coupling reaction of the aryl halides with aryl halides, phenols, amines and N-heterocyclic amines. In the coupling reaction the yields of the products were good and the catalyst was recovered by simple filtration method and can be reused.