Preparation of Bifunctional Mesoporous Silica Nanoparticles by Orthogonal Click Reactions and Their Application in Cooperative Catalysis

Abstract

The synthesis of bifunctional mesoporous silica nanoparticles is described. Two chemically orthogonal functionalities are incorporated into mesoporous silica by co-condensation of tetraethoxysilane with two orthogonally functionalized triethoxyalkylsilanes. Post-functionalization is achieved by orthogonal surface chemistry. A thiol-ene reaction, Cu-catalyzed 1,3-dipolar alkyne/azide cycloaddition, and a radical nitroxide exchange reaction are used as orthogonal processes to install two functionalities at the surface that differ in reactivity. Preparation of mesoporous silica nanoparticles bearing acidic and basic sites by this approach is discussed. Particles are analyzed by solid state NMR spectroscopy, elemental analysis, infrared-spectroscopy, and scanning electron microscopy. As a first application, these particles are successfully used as cooperative catalysts in the Henry reaction.

Sulfonic acid functionalized mesoporous SBA-15 as catalyst for styrene carbonate synthesis from CO2 and styrene oxide at moderate reaction conditions

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Careful investigation of the hydrosilylation of olefins at poly(ethylene glycol) chain ends and development of a new silyl hydride to avoid side reactions

“…For example, the Karstedt catalyst‐catalyzed hydrosilylation reaction is one of the key reactions to prepare various functional poly(ethylene glycol)s (PEGs). Due to high biocompatibility and low toxicity, PEG‐derived functional polymers have been widely employed as core components in many biorelated materials, surface modifications microcontact printing, and polymer electrolytes …”

Preparation of Functional Alternating Polymer Brushes and Their Orthogonal Surface Modification through Microcontact Printing

“…Therefore, the chemicalm odificationo fg lass and silicon surfaces is of great interest form any applicationsi nm aterials science ando ther research fields. [1] Surfacem odification is ah ighly valuablea pproach to improveh ydrophilicity, [2,3] reactivity, [4] catalytic activity, [5] or biological compatibility, [6] rendering the chemically modified materials uitable for medical applications. [8] Polymer brushes are highly important in the field of surface modification owing to the abilityo ft he brush materialt oc hange surface properties significantly.F or example, it is possible to tune the wettability [9] or the protein [10] and cell [11] adsorption behavior through such am odification.…”