MCM-41-supported cis-diaquabis(6,6′-dichloro-2,2′-bipyridine) ruthenium(II) complex. Immobilisation, characterisation and catalytic activities

Abstract

cis-[Ru^II(6,6′-Cl₂bpy)₂(OH₂)₂](CF₃SO₃)₂ (6,6′-Cl₂bpy=6,6′-dichloro-2,2′-bipyridine) was immobilised into the mesoporous molecular sieve MCM-41 by a simple and direct method and the highest loading of cis-[Ru^II(6,6′-Cl₂bpy)₂(OH₂)₂](CF₃SO₃)₂ achieved was 8.4 wt%. The supported ruthenium complex, designated as Ru/MCM-41, has been characterised by elemental analyses, N₂ adsorption isotherm, X-ray diffraction (XRD), thermogravimetric and differential thermal analyses (TG-DTA), UV-visible and FT-Raman spectroscopies. XRD spectra showed that the immobilised cis-[Ru^II(6,6′-Cl₂bpy)₂(OH₂)₂](CF₃SO₃)₂ was not in a crystalline form and the MCM-41 structure was retained. Preliminary studies revealed that the Ru/MCM-41 materials catalysed the oxidation of alkanes by tert-butylhydroperoxide (TBHP) with high turnover. High catalytic activity has been obtained with low ruthenium loading catalysts.