Gold nanoparticles (Au-NPs) have been prepared using N-heterocyclic thiones (NHTs) as ligand stabilisers. These Au-NPs have been shown to be very stable, even in air, and have been characterized by a combination of several techniques (TEM, HR-TEM, STEM-HAADF, EDX, DLS, elemental analysis and H NMR). These nanoparticles are active in the catalytic reduction of nitroarenes to anilines.

Small Pt nanoparticles (1.3–1.7 nm) stabilized by N-heterocyclic thiones are efficient catalysts in the mono- and di-hydroboration of alkynes.

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The oxidation of sulfides to sulfoxides and sulfones provides valuable sulfur-containing chemical compounds that are used in the pharmaceutical agrochemical industry. Although some tungsten catalytic systems have been applied to sulfide oxidation, the most desirable heterogeneous catalytic protocols have not been described. The copper, nickel and zinc tungstates powders obtained by the polymeric precursor method and the evaluation of their catalytic activity in thioanisole oxidation were investigated. Thioanisole was oxidized by hydrogen peroxide to sulfoxides and sulfones and the presence of catalyst accelerates the conversion. Of the three catalysts, copper tungstate was the most efficient in the conversion process followed by nickel tungstate and finally zinc tungstate. The copper tungstate has higher hydrogen consumption, indicating a higher oxygen content on the surface and the ability to increase surface mobility, which increases the conversion and selectivity of the process. The addition of 0.1 mL of hydrogen peroxide enhanced the conversion and increased the amount of sulfone produced. The ideal reaction time was 12 hours and the optimum temperature was 75 °C.

Summary Copolymers are polymers consisting of different repeat units and their production is usually motivated by the changing of polymers properties. An important application are the transportation of drugs within the organism with the aim of controlling the release of the substance. The synthesis of these new copolymers is based on simple semi‐synthesis and low cost. The synthetic routes are based on the interaction of the graft copolymer (PMMA‐g‐PEG) with a variety of reagents such as acetic anhydride, acetic acid, methyl iodide, sulfuric acid and hydrochloric acid. The products from these reactions of esterification, methylation, acetylation and halogenation will be characterized by Fourier‐transforminfrared spectroscopy (FTIR). The use of this technique allowed us to detect the main absorption bands related to the CO bonds, C‐Cl, R‐COOR and CO, thus confirming the efficiency of modification reactions of the graft copolymer chain.

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