Covalent attachment of a biomimetic Ru-(terpy)(bpy) complex on silica surface: Catalytic potential

The Ru-containing modified silica [Ru-II(terpy)(4'Mebpy/4CONH(CH2)(3)SiO3/2)Cl](+)m center dot zSiO(2) has been prepared by covalent attachment on silica surface of biomimetic [Ru-II(terpy)(4-CO2H-4'-Mebpy)Cl](+). complex through the formation of a pseudo-peptide bond. The catalytic ability of bio-derived silica for alkene oxidation with (HOOBu)-Bu-t has been evaluated exhibiting significant efficiency and, in some cases, showing increased activity compared vs. the corresponding 'net' [Ru-II(terpy)(4-CO2H-4'-Mebpy)Cl](+) complex. The data supported that the covalently attached ruthenium complex preserves the catalytic behaviour of the 'net' ruthenium complex indicating that the presented grafting process was successful. (C) 2012 Elsevier Ltd. All rights reserved.