A catalytically active tetrameric cubane-like complex [Co-4(III)(mu(3)-O)(4)(mu-O2CCH3)(4)(py)(4)] (1) has been prepared, structurally characterised by single crystal X-ray diffraction, and immobilised on a porous organomodified silica, which is amorphous in nature. The resulting supported reagent has been found to promote the efficient and selective oxidation of benzylic alcohols and cyclohexanols with TBHP as the oxidant. The catalyst can be reused without any significant loss of activity. (c) 2007 Elsevier B.V All rights reserved.