Aerosol‐Spraying Synthesis of Periodic Mesoporous Organometalsilica Spheres with Chamber Cavities as Active and Reusable Catalysts in Aqueous Organic Reactions

Abstract

Organometal-bridged periodic mesoporous catalysts with uniform spheres containing cavities in chambers were synthesized by rapid aerosol-spray assisted co-condensation between organometallic silane and tetraethoxysilane (TEOS) in the presence of cetyltrimethyl ammonium bromide (CTAB) and NaCl double templates. The as-prepared M -PPh 2 -PMO(H) catalysts ( M = Pd 2 + , Rh + and Ru 2 + ) were used in various water-medium organic reactions with the aim of diminishing environmental pollution from organic solvents. These catalysts exhibited high catalytic activities and selectivities owing to the high surface area, the uniform distribution of active sites, the ordered mesoporous channels and especially, the cavities as microreactors which facilitated the diffusion and adsorption of organic reactants. Meanwhile, they also displayed strong durability and could be used repeatedly owing to the organometals incorporated into silica walls and the presence of chamber cavities which could effectively protect the ordered mesoporous structure from damage and also inhibit the leaching of active sites.

An imidazolium-based organopalladium-functionalized organic–inorganic hybrid silica promotes one-pot tandem Suzuki cross coupling–reduction of haloacetophenones and arylboronic acids

“…On the basis of the obtained heterogeneous catalyst 3, the Suzuki cross-coupling of 4-iodoacetophenone and phenylboronic acid to 1-(biphenyl-4-yl) ethanone, followed by the reduction of 1-(biphenyl-4-yl) ethanone to 1-(biphenyl-4-yl) ethanol were investigated at first [18][19][33][34][35][36][33][34][35][36][37][38][39]. According to the reported method [18], several bases were screened based on the same reaction solvent and reaction temperature in the literature.…”

Facile Synthesis of Yolk-Shell-Structured Triple-Hybridized Periodic Mesoporous Organosilica Nanoparticles for Biomedicine

“…However, the Si‐O‐Si frameworks of mesoporous silica still have some limitations and drawbacks in the biobehaviors and performance, and their medical translation is still a big challenge. The periodic mesoporous organosilicas (PMOs) prepared by using bridged silsesquioxane with the type of (R′O) 3 Si‐R‐Si(R′O) 3 as precursors provide organic groups homogeneously incorporated frameworks . The organic groups incorporated in the frameworks can greatly change the properties of mesoporous siliceous nanoparticles and endow them with better performance in biomedical applications .…”

Periodic Mesoporous Organosilicas: from simple to complex bridges; a comprehensive overview of functions, morphologies and applications

“…Thus, different bis-and tris-silylated phosphine complex precursors with different metals, i.e., Pd(II), Rh(I), Ru(II) and Au(I), were co-condensed with TEOS, BTEB and/or 4,4 0 -bis(triethoxysilyl)biphenyl. 201,202,255,256 These materials exhibited similar activities to the homogeneous complexes and could be recycled repeatedly due to their resistance to leaching. Moreover, they were usually more active than similar grafted materials since the grafting method could lead to pore blockage.…”

“…Rh, Pd and Ru have been incorporated by complexation with the phenylphosphino ethylsilane (69). 201 Several other precursors containing different metals have been synthesized, to be co-condensed simple silanes or bis-silanes. A few typical examples, with references, are shown in Table 13.…”