Silica-based organic–inorganic hybrid materials prepared from chiral precursors

New organic–inorganic hybrid silica-based materials containing chiral moieties have been prepared by sol–gel hydrolysis–condensation of tartaramide enantiomer precursors. The new chiral precursors were characterized by means of FTIR, 13C, 29Si and 1H NMR, specific rotation and elemental analysis. Their hydrolysis led to the formation of hybrid materials containing an organic (chiral)–inorganic (silica) network. The obtained chiral xerogels were studied using 13C and 29Si CP MAS NMR spectra, which indicated the insertion of the chiral precursors into the inorganic network, as well as condensation degrees higher than 73%. XRD was also applied in order to analyse the xerogel's organization, indicating that the catalyst played a fundamental role in the kinetics of these hybrid materials.

RésuméDe nouveaux matériaux hybrides organique–inorganique nanostructurés comportant des unités chirales ont été préparés par voie sol–gel à partir de dérivés du tartaramide. Les xérogels chiraux obtenus montrent l'insertion de l'unité organique chirale au sein du matériau. Les diagrammes de diffraction des RX mettent clairement en évidence l'influence des paramètres cinétiques sur l'organisation des solides.