We report the selective oxidation of glucose to gluconic acid under mild conditions and show that if a basic support is used then the reaction can be carried out without the addition of sacrificial base or pH control. The use of sol-immobilisation prepared catalysts supported on magnesium oxide facilitates the use of ambient air as an oxidant source. These mild conditions resulted in an excellent selectivity towards gluconic acid. Different heat treatments result in an improvement in the activity of the catalyst, these improvements are discussed in terms of XRD, DRIFTD and TEM analysis of the catalysts, despite significant particle growth and phase segregation occurring during the thermal treatments.

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In this work we expand on our previous studies on the oxidation of cyclic alkenes using supported gold nanoparticles together with catalytic amounts of peroxides. We demonstrate that various sized cyclic alkenes can be oxidised by this catalyst, under green conditions, without solvent and using air as the oxidant gas. The effect of support, preparation method and choice of metal have been investigated, we demonstrate that supported gold is superior to palladium or a gold palladium alloy, we show that oxides provide the best support for these gold catalysts and the preparation methods that afford the smallest particles are the most active. We show that the reactivity of the cyclic alkenes is related to the ring size with the smaller rings more reactive than the larger rings at the same temperature.The selectivity to the epoxide is dependent on the size of the cyclic alkene ring. In particular, the epoxide selectivity is very low for rings containing fewer than seven carbon atoms. We discuss the origins of this selectivity effect, using DFT calculations to investigate the effect of ring strain on the intermediates and reaction products.

We report the solvent‐free oxidation of 1‐hexene with air by using supported gold catalysts with a catalytic amount of tert‐butyl hydroperoxide (TBHP) as initiator. We confirm that gold supported on graphite is an effective catalyst for such oxidations and that graphite was the preferred support. Preparation of catalysts using modified sol‐immobilisation was found to be effective, particularly when the PVA stabiliser was removed by a solvent treatment prior to the reaction.