Supported gold nanoparticles catalyze the unprecedented insertion of a silylborane into the C−O bond of oxetanes and unactivated epoxides, forming γor β-silyloxy boronates in good to excellent yields. In the silaboration process the boron moiety is acting as a nucleophile and the silyl as an electrophile. No external additives or ligands are required, while the catalytic system is recyclable and reusable.

In the presence of Au/TiO2 (1 mol %), terminal alkynes react quantitatively with stoichiometric amounts of the unactivated digermane Me3Ge-GeMe3, forming exclusively cis-1,2-digermylated alkenes. We also establish the Au/TiO2-catalyzed hydrogermylation of terminal allenes with Et3GeH, which exhibits a highly regioselective mode of addition on the more substituted double bond forming vinylgermanes. Additionally, we provide preliminary results regarding the Pd nanoparticle-catalyzed C–C coupling of 1,2-digermyl alkenes with aryl iodides.

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Diethylsilane (Et2SiH2), a simple and readily available dihydrosilane, that exhibits superior reactivity, as compared to monohydrosilanes, in a series of reductive transformations catalyzed by recyclable and reusable Au nanoparticles (1 mol‐%) supported on TiO2. It reduces aldehydes or ketones almost instantaneously at ambient conditions. It can be used in a one pot rapid reductive amination procedure, in which premixing of aldehyde and amine is required prior to the addition of the reducing agent and the catalyst, even in a protic solvent. An unprecedented method for the synthesis of N‐arylisoindolines is also shown in the reductive amination between o‐phthalaldehyde and anilines. In this transformation, it is proposed that the intermediate N,2‐diphenylisoindolin‐1‐imines are reduced stepwise to the isoindolines. Finally, Et2SiH2 readily reduces amides into amines in excellent yields and shorter reaction times relative to previously known analogous nano Au(0)‐catalyzed protocols.

Gold nanoparticles supported on TiO 2 (1 mol%) catalyze the reduction of a series of functionalized quinolines into 1,2,3,4-tetrahydroquinolines using hydrosilanes/ethanol (hydride/proton) as the reductant system. A typical reaction requires 4 molar equivalents of phenyldimethylsilane (reductant of choice), 4 molar equivalents of ethanol as a reagent and heating to 70 o C under solvent free conditions. The isolated yields are moderate to excellent and in certain cases the reaction rate is exceedingly fast. Mechanistic analysis revealed the stereoselective addition of two hydrides (from hydrosilane) on positions C2 and C4 of the quinoline ring and two protons (from ethanol) on positions C3 and the nitrogen atom.