Functional and Mixed Ligand Silicon Alkoxides for More Facile Hydrolysis

Functional and Mixed Ligand Silicon Alkoxides for More Facile Hydrolysis 

Alkyl alkoxysilanes undergo quick hydrolysis and polycondensation in acidic medium. This has been exploited in combination with self-assembly of long-chain alkyl trialkoxysilanes driven by hydrophobic interactions that opened prospects for surfectant- and template-free synthesis of ordered mesoporous silicas. This approach has been developed strongly by Shimojima and Kuroda [24]. 

The most significant effect in improving the reactivity of alkoxysilanes is achieved by introduction of chelating ligands. It is associated with the increase 

The synthesis of most often used glycol derivatives is carried out on long-term reflux with removal of the released aliphatic alcohol by distillation [20]. The resulting silicon glycolates are quite sensitive to moisture and are hydrolyzed by neutral water without any need of protolytic catalysis. 

The anionic forms of polyol complexes (derived from alcohob bearing three or more OH groups) are stabilized thermodynamically and are not prone to hydrolysis in aqueous solutions. They can easily be obtained at room temperature via interaction of sodium silicate with polyols, for example, sorbitol [26]. Formation of polyol complexes has been identified as possible mechanism in uptake and transport of silica for formation of endoskeletons in marine single-cell organisms such as diatoms. 

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