Hydrotalcite-supported gold nanoparticles (Au/HT) were found to be a highly efficient heterogeneous catalyst for the aerobic oxidation of alcohols under mild reaction conditions (40 8C, in air). This catalyst system does not require any additives and is applicable to a wide range of alcohols, including less reactive cyclohexanol derivatives. This Au/HT catalyst could also function in the oxidation of 1-phenylethanol under neat conditions; the turnover number (TON) and turnover frequency (TOF) reached 200,000 and 8,300 h À1 , respectively. These values are among the highest values compared to those of other reported catalyst systems at high conversion. Moreover, the Au/HT can be recovered by simple filtration and reused without any loss of its activity and selectivity.

Hydroxyapatite-supported gold nanoparticles (AuHAP) can act as highly efficient and reusable catalysts for the oxidation of diverse silanes into silanols in water; this is the first catalytic methodology for the selective synthesis of aliphatic silanols using water under organic-solvent-free conditions.

The oxidative lactonization of various diols using molecular oxygen as a primary oxidant can be efficiently catalyzed by hydrotalcite-supported Au nanoparticles (Au/HT). For instance, lactonization of 1,4-butanediol gave g-butyrolactone with an excellent turnover number of 1400. After lactonization, the Au/HT can be recovered by simple filtration and reused without any loss of its activity and selectivity.

A picky catalyst: Hydrotalcite‐supported gold nanoparticles (Au/HT) efficiently catalyze the deoxygenation of epoxides to alkenes using molecular hydrogen as an ideal reductant. Various epoxides have been deoxygenated to the corresponding alkenes (see picture) with over 99 % selectivity. The high selectivity is based on the concerted effect between basic sites of HT and the gold nanoparticles.

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