Facile one-pot approach to the synthesis of chiral periodic mesoporous organosilicas SBA-15-type materials

The synthesis of a chiral PMO SBA-15-type material from 100% purely organic monomers, 1,2-bis(triethoxysilyl)ethane and bis-silylated chiral ligands, by an easy one-pot methodology has been studied. Furthermore, these chiral periodic mesoporous solid materials with an incorporation as high as 50 mol% of dimethyl tartrate-derived chiral auxiliary precursor (Sharpless ligand) have been synthesized, without any reduction in the textural properties with reference to the ordering of the material. FTIR and NMR solid-state techniques confirm the presence of the chiral organic precursor in the SBA-15-type material framework. The thioanisole asymmetric oxidation reaction has been used to validate the heterogeneously synthesized catalyst activity, achieving moderate enantiomeric excess (ee) and satisfactory yield to sulfoxide up to 30% and 71%, respectively, corroborating the inclusion of the chiral tartrate moiety into the inorganic silica framework.

Graphical abstractFacile and unprecedented one-pot approach to the synthesis of chiral PMO SBA-15-like material based on a tartrate derivative chiral precursor and on a non-chiral bis-organosilane.Figure optionsDownload full-size imageDownload high-quality image (68 K)Download as PowerPoint slide