Thiamine supported on core-shell silica magnetic nanoparticles: a highly efficient and recyclable organocatalyst for the silylation of hydroxyl groups

摘要

A green and highly efficient silylation of hydroxyl groups with hexamethyldisilazane using biodegradable thiamine-functionalized Fe3O4@SiO2 magnetic nanoparticles is described. The thiamine-functionalized silica-supported magnetic (Fe3O4@SiO2@VB1) nanocatalyst was characterized successfully by infrared spectroscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy, powder X-ray diffraction and thermogravimetric analysis. Thiamine hydrochloride as well as anchored thiamine on the surface of magnetic nanoparticles has a higher catalytic activity for the protection of alcohols and phenols under mild reaction condition and short reaction times. Furthermore, the nanocatalyst could be recovered using an external magnet and reused with almost consistent activity.