Novel layered zeolitic organic−inorganic materials (MWW-BTEB) have been synthesized by intercalation and stabilization of arylic silsesquioxane molecules between inorganic zeolitic MWW layers. The organic linkers are conformed by two condensed silyl-arylic groups from disilane molecules, such as 1,4-bis(triethoxysilyl)benzene (BTEB), which react with the external silanol groups of the zeolitic layers. The hybrids contain micropores within the inorganic layers and a well-defined mesoporous system in between the organic linkers. An amination post-treatment introduces basic groups in the organic linkers close to the acid sites present in the structural inorganic counterpart. Through this methodology it has been possible to prepare bifunctional acid−base catalysts where the acid sites are of zeolitic nature located in the inorganic building blocks and the basic sites are part of the organic structure. The resultant materials can act as bifunctional catalysts for performing a two-step cascade reaction that involves the catalytic conversion of benzaldehyde dimethylacetal into benzylidene malononitrile.

Non-ordered porous hybrid materials with different distribution of pore sizes have been synthesized from organic-inorganic bridged silsesquioxane precursors using an NH 4 F catalyzed sol-gel route. This methodology has allowed to obtain high surface area porous materials in absence of structural directing agents or surfactant molecules. A variety of organic linkers, such as benzene, disulfide, diamine, ethane and ethylene groups, were incorporated within the framework, and the effective integration was confirmed by elemental and thermogravimetrical analyses, Raman and NMR spectroscopies. The pore dimensions of the hybrids could be modified, within the mesoporous range, with the NH 4 F synthesis and the characteristics of the organic linker. Basic catalytic active sites have been introduced in the organic linkers of the hybrid porous materials that are active and selective for Knoevenagel condensations, showing the possibility to heterogenize organic catalysts while preserving their activity and selectivity by means of these porous organic-inorganic hybrids.

A family of hybrid mesoporous materials with high temperature stability was obtained by the suitable covalent combination of two types of siloxane precursors. Specifically, cubic T(8) polyhedral oligomeric (POSS) and aryl bridged silsesquioxane monomers (1,4-bis(triethoxysilyl)benzene, BTEB) play the role of nanobuilders. An optimal molar ratio of the two precursors (5-25 mol% of total silicon content from the BTEB disilane) generated a homogenous, highly accessible, and well-defined mesoporous material with hexagonal symmetry and narrow pore-size distribution. Physicochemical, textural, and spectroscopic analysis corroborated the effective integration and preservation of the two different nanoprecursors, thereby confirming the framework of the mesoporous hybrid materials. A post-synthesis amination treatment allowed the effective incorporation of amino groups onto the aryl linkers, thereby obtaining a stable and recyclable basic catalyst for use in C-C bond-formation processes.