Synthesis of Organoalkoxysilanes: Versatile Organic–Inorganic Building Blocks

Organic–inorganic building blocks are an important class of hybrid materials due to the synergistic versatility of organic compounds with the robust properties of inorganic materials. Currently, the growing interest in silica hybrid materials to modify the physical and chemical properties of the silica network has led to an increasing interest in organoalkoxysilanes. A general formula of R-[Si-(OR’)3]n, with OR’ as a hydrolysable alkoxy group and R acting as the organic functional group (n ≥ 1), has led to precursors for many molecules. By introducing adequate organic moieties (R), organoalkoxysilanes effectively engage in surface and matrix modification of silica-based materials with smart-responsive units, coupling agents, targeting moieties, bioactive moieties etc., opening promising applications, specifically biomedical ones. Several synthetic procedures have been established to introduce the alkoxysilane moieties, including hydrosilylation, coupling reactions, and addition reactions to isocyanates. Herein, we review synthetic routes to organoalkoxysilanes and the relationship between structural features to design appropriate organoalkoxysilanes for specific applications.