Multifunctional yolk–shell microspheres are synthesized through a combined interfacial sol–gel coating and surfactant-templating co-assembly method and are demonstrated as efficient and easily recyclable nanocatalysts for catalytic epoxidation of styrene.

A mesoporous silica (SBA-15)-supported pyrimidine-substituted N-heterocyclic carbene iridium complex was prepared and used as a catalyst for both environmentally friendly N-alkylation of amines and b-alkylation of secondary alcohols with primary alcohols. The structure of the supported iridium catalyst was characterized by Fourier transform infrared (FT-IR), 13 C and 29 Si solid-state nuclear magnetic resonance (NMR), small-angle X-ray scattering (SAXS), transmission electron microscopy (TEM), iridium K-edge X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopic analyses which demonstrated that the coordination environment of the iridium centre and the 3-dimensional-hexagonal pore structure of SBA-15 were retained after the immobilization. The catalyst was found to be highly efficient for both kinds of reaction on a wide range of substrates under mild conditions. Moreover, the sup-ported iridium catalyst was obviously superior to the unsupported one in the N-alkylation of aniline and b-alkylation of 1-phenylethanol with benzyl alcohol as substrate, which indicated that not only the iridium complex moiety but also the support material contributed to the catalytic activity of the supported iridium catalyst in these reactions. The supported iridium catalyst can be easily recycled by simple washing without chemical treatment, and exhibited excellent recycling performance without notable decrease in catalytic efficiency even after twelve test cycles for N-alkylation of aniline with benzyl alcohol, nine cycles for N-alkylation of different amines with different alcohols, and eight cycles for b-alkylation of 1phenylethanol with benzyl alcohol, respectively.

An efficient arylation of electron-poor arenes has been developed without the addition of external ligands or in the presence of a catalytic monoprotected amino acid which assisted the reaction to proceed under mild conditions. The meta-selectivity was observed under both conditions.

Multifunctional microspheres with core-shell structures consisting of a core of nonporous carbon-protected magnetite particles, a transition layer of active Pd (or Pt) nanoparticles, and an outer shell of ordered mesoporous silica with perpendicularly aligned pore channels were synthesized based on colloid and interface chemistry. As a magnetically separable catalyst system, such microspheres hold a good potential in liquid phase catalysis.