In recent years, research efforts in the field of ordered mesoporous materials are shifting towards either hybrid materials, containing both inorganic (typically silica) and organic functionalities, or towards variants that do not contain silica at all. Promising examples of hybrid materials are periodic mesoporous organosilicas (PMOs); examples of non-siliceous mesoporous materials are carbons, polymers and metal oxides. They can be further tuned to obtain structures with a wide range of functional groups, and are candidates for applications in adsorption, catalysis, sensoring, microelectronics and several other applications.

Various symmetrically and asymmetrically substituted N-heterocyclic carbene (NHC) ligands bearing aliphatic nitrogen-containing side groups have been synthesised. In our attempts to isolate the corresponding second-generation Grubbs catalysts, we were unsuccessful when using the symmetrical aliphatic NHC ligands. For the asymmetrical ligands bearing an aliphatic moiety on one side and an aromatic mesityl group on the other side, substitution of a phosphine ligand was achieved. The performance of a so-formed series of Ru-based metathesis initiators has been evaluated for the ring-opening metathesis polymerisation (ROMP) of cycloocta-1,5-diene and the ring-closing metathesis (RCM) of diethyl diallylmalonate.

A novel synthesis of diastereoselective pure periodic mesoporous ethenylene-silicas is presented, using (a) the homemade E-diastereoisomer of bis(triethoxysilyl)ethene, (b) a more efficient extraction procedure of the template P123 and (c) an ultra-fast synthesis procedure.

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A new family of periodic mesoporous organosilicas with 100% E-configured ethenylene-bridges and controllable pore systems is presented. 2D hexagonally ordered hybrid nanocomposites consisting of cylindrical pores are obtained, of which some are filled with solid material. The architectural composition of these hybrid materials can be accurately controlled by fine-tuning the reaction conditions; that is, there is a unique correlation between the reaction mixture acidity and the amount of confined mesopores. This correlation is related to the filling of the pores with solid material whereby the length of the pore channels can be tailored. Hereby the mesophase either shifts toward long-ranged 2D hexagonally ordered open cylinders or toward 3D hexagonally ordered interconnected spheres. The synthesis of these organic−inorganic hybrid composites is straightforward via the direct condensation of E-1,2-bis(triethoxysilyl)ethene, in the presence of pluronic P123. The true nature of these periodic mesoporous organosilicas is disclosed by means of nitrogen gas physisorption, nonlocal density functional theory, SAXS, TEM, and electron-tomography.