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A facile synthesis of a new class of reactive porous materials is reported: hierarchically porous hydrogen silsesquioxane (HSiO1.5, HSQ) monoliths with well-defined macropores and mesopores. The HSQ monoliths are prepared via sol-gel accompanied by phase separation in a mild condition, and contain micrometer-sized co-continuous macropores and high specific surface area reaching up to 800 m2 g−1 because of the small mesopores. A total preservation of Si-H, which is always an issue of HSQ materials, is confirmed by 29Si solid-state NMR. The HSQ monolith has then been subjected to reduction of noble metal ions to their corresponding metal nanoparticles in simple aqueous solutions under an ambient condition. The nanoparticles produced in this manner are immobilized on the HSQ monolith and are characterized by X-ray diffraction (XRD) and high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). Both the bare HSQ and nanoparticles-embedded HSQ are promising as heterogeneous catalysts, exhibiting reusability and recyclability. [ABSTRACT FROM AUTHOR]

We report here a new and efficient route to symmetrical disiloxanes from their corresponding alkoxysilanes using Meerwein's reagent as mediator and potassium carbonate as additive under mild reaction conditions in acetonitrile. Our methodology is very simple, economic, and high yielding. We have also proposed a reaction mechanism with the plausible silyloxonium intermediates. [ABSTRACT FROM AUTHOR]

We developed a new facile method to fluorosilanes from alkoxysilanes using Meerwein's reagent. Our protocol afforded fluorosilanes in excellent yields in various organic solvents including acetonitrile under mild reaction conditions at room temperature. We also proposed a reaction mechanism with the probable silyloxonium intermediates. [ABSTRACT FROM AUTHOR]

Three chiral phosphine ligands containing an allylsilyl group at the terminus of the side chain were prepared and immobilized on a silica gel surface by use of the allylsilane modification method. The silica-supported chiral phosphine ligands were used for rhodium-catalyzed hydrogenation and palladium-catalyzed allylic alkylation and showed high enantioselectivity. [Copyright &y& Elsevier]

Three allyl groups on silicon are essential for the successful 1,4-addition reaction to α,β-unsaturated ketones and esters. [ABSTRACT FROM AUTHOR]