Niobium-containing silica materials obtained by deposition via liquid-phase grafting or dry impregnation of niobocene(iv) dichloride are active and selective catalysts in the epoxidation of alkenes in the presence of aqueous hydrogen peroxide. The generation of the catalytically-active Nb species was followed step-by-step, and investigated using a combined DR-UV-Vis, NIR, Raman, XRD, XANES and EXAFS analyses. At the end of the grafting procedure, the nature of the surface active species can be described as an oxo-Nb(v) site, tripodally grafted onto the silica surface in close proximity to other Nb(v) centres. The liquid-phase methodology provides a better dispersion of the metal sites onto the siliceous support than the dry-impregnation approach. The niobium-silica catalysts were then tested in the epoxidation of cyclohexene and 1-methylcyclohexene, as model substrates.

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CO‐vering gold: An organometallic approach to the synthesis of CO‐protected Au–Fe nanoparticles led to solutions of colloids with hydrodynamic diameters between 4 and 300 nm, from which [Au21{Fe(CO)4}10]5− (picture: metal frame; Au yellow, Fe green), [Au22{Fe(CO)4}12]6−, [Au28{Fe(CO)3}4{Fe(CO)4}10]8−, and [Au34{Fe(CO)3}6{Fe(CO)4}8]8− were isolated. Their X‐ray structures resemble those of gold–thiolate clusters.

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Small-sized Pt-nanoparticles (NPs) of 1.5 nm, generated by metal vapor synthesis, and supported onto Ketjenblack proved to be the first example of a heterogeneous monometallic Pt−NP-based catalyst, which was stabilized by ethylene during conversion of glycerol to lactate (LA). A LA chemoselectivity of 95% was obtained in three consecutive catalytic runs.