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Highly dispersed palladium nanoparticles were synthesized in the presence of immobilized ionic liquid on mesoporous silica SBA-15. PdNPs(2.4 nm)_me-Im@SBA-15 catalyst was prepared by the reduction using NaBH4 as the reducing agent with controlled feed rate and has been investigated as ligand-free catalyst for Suzuki–Miyaura cross-coupling reaction at room temperature in aqueous solution under air. PdNPs catalyst was also prepared in situ from PdCl4_me-Im@SBA-15 during the reaction and demonstrated high activity and stability towards nitrobenzene hydrogenation at high temperature. Both catalysts were reusable at least for four recycle processes without significant loss in activity with simple procedure. The catalysts were characterized by TEM, EXAFS, FTIR and XPS. Keywords: Palladium nanoparticle, Ionic liquid, SBA-15, Suzuki–Miyaura cross-coupling, Hydrogenation

A series of gold nanoparticles (AuNPs) with controllable size were prepared from immobilized gold-containing ionic liquid on SBA-15 (AuCl_me-Im@SBA-15) at room temperature. AuNPs size and shape could be controlled inside porous SBA-15 in the presence of immobilized 1-methyl-3-(3-trimethoxysilyl- propyl)-imidazolium chloride by controlling a concentration and a feed rate of a reducing agent NaBH 4 . The smallest AuNPs with the average size of 1.6 nm was obtained at a fixed feed rate of 0.2 ml/min with 4 mM NaBH 4 . The transformation of AuNPs shape from spherical to capsule-like NPs was observed at low feed rate of 0.04 ml/min. The prepared AuNPs catalysts were characterized by TEM, XPS, FTIR, and XRD. The catalyst with the smallest NPs, AuNP(1.6 nm)_me-Im@SBA-15, exhibited the highest catalytic performance in p -nitrophenol hydrogenation reaction at room temperature. Moreover this catalyst was reusable up to four recycle processes.

Supported metal nanoparticles hold great promise in heterogeneous catalysis as active and reusable catalysts for various organic transformations. Preparation methods of metal nanoparticles with excellent control over size, shape, and morphology on supports has significantly advanced to improve the performances of the resulting catalysts. Here, we aim to discuss the development of supported metal nanoparticles on mesoporous silica SBA-15 in the presence of immobilized ionic liquids mostly based on examples from the previously reported results. This review highlights the preparation methods for size-controlled syntheses and the immobilization of metal nanoparticles on solid supports, especially SBA-15 by various techniques.

A novel and simple method for the synthesis of aromatic linear polyester amides has been developed by the carbonylation–polycondensation reaction of aromatic diiodides and aminohydroxy compounds in the presence of ImmPd-IL@SBA-15 catalytic system. Polyester amides with moderate intrinsic viscosity were synthesized in excellent yields using the ImmPd-IL@SBA-15 catalyst and represents efficient heterogeneous and phosphine-free approach for the synthesis of various linear polyester amide derivatives. The ImmPd-IL@SBA-15 catalyst solves the basic problem of catalyst recovery and furnishes good to excellent yield of desired product within short reaction time. The recycled catalyst was characterized using the XPS and TEM analysis. The catalyst was recycled four times without significant loss in activity. Catalytic polyester amide synthesis