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• Gold (1 wt.%) was loaded on several carbon materials by two different methods. • Activated carbon, carbon xerogel, microdiamonds, nanodiamonds and graphite were used. • Materials were used for the microwave-assisted solvent-free phenylethanol oxidation. • The highest acetophenone yield (99.9%) was obtained for Au loaded on microdiamonds. • This catalyst was able to maintain higher activity up to several recyclability cycles. Gold (1 wt.%) was loaded on several carbon materials, namely, polymer based carbon xerogel, activated carbon, microdiamonds, nanodiamonds, graphite and silicon carbide by double impregnation and sol immobilisation. The obtained catalysts were characterised by N 2 adsorption at -196 ºC, high-resolution transmission electron microscopy, high-angle annular dark-field imaging (Z-contrast), temperature programmed desorption, atomic absorption spectroscopy and X-ray photoelectron spectroscopy. The obtained materials were tested on the microwave-assisted solvent-free oxidation of 1-phenylethanol by tert -butyl hydroperoxide (TBHP) to produce acetophenone. The results showed that the catalytic activity was influenced by several factors, namely, the nature of the support, reaction time and temperature, amount of catalyst, presence of additives, among others. The best values for acetophenone yield (99.9%) were obtained with Au deposited on microdiamonds by the colloidal method. Catalyst recyclability was tested up to six consecutive cycles at the optimized conditions for each catalyst, and it was found that Au on microdiamonds, prepared by the colloidal method, also maintained higher activity after several reaction cycles as compared to the other carbon supports. [ABSTRACT FROM AUTHOR]

Reaction of cadmium acetate hydrate with sodium 2-[2-(4,4-dimethyl-2,6-dioxocyclohexylidene)hydrazinyl]terephthalate (Na 2 HL), in the presence of imidazole (im), leads to the polymeric species [Cd(im) 3 (µ,η-HL-1κOO′:2κO″O‴)] n ( 1 ) that is characterized by IR spectroscopy, elemental analysis, UV–Vis absorption spectroscopy and X-ray diffraction analysis. Complex 1 was successfully tested as catalyst for the peroxidative oxidation of alcohols (1-phenylethanol and cyclohexanol) to the corresponding ketones under microwave irradiation, with no added solvent and under mild conditions. The use of tert -butylhydroperoxide as oxidant, of TEMPO as additive, and a temperature of 80 °C leads in 1 h to a yield of acetophenone (from 1-phenylethanol) of nearly 70% or to a cyclohexanone yield (from cyclohexanol) of 66%. A comparison between the catalytic activity of 1 with those (also studied in this work) shown by Cu(II) complexes bearing the same or related hydrazo ligand is presented. [ABSTRACT FROM AUTHOR]