N,N- Dialkylcarbamato complexes as precursores for the chemical implantation of metal cations on a silica support. Part II . Platinum(II) and its further reduction to platinum nanoparticles

Implantation of platinum(II) on a commercial silica has been carried out under mild conditions by using N,N-dialkylcarbamato complexes as reactive precursors, in a biphasic liquid/solid system, carbon dioxide and secondary amine being released during the reaction with the acidic silanol groups of the support. Information about the coordination sphere of the silica-supported platinum(II) has been obtained by IR, XPS, solid-state NMR spectroscopy and WAXS measurements, which agree with chemical evidence. Reduction, either thermal or with dihydrogen, produces platinum nanoparticles, which were studied by conventional techniques and shown to be catalytically active in the hydrogenation of cyclohexene.