Preparation of Iron-Containing Schiff Base and Ionic Liquid Based Bifunctional Periodic Mesoporous Organosilica and Its Application in the Synthesis of 3,4-Dihydropyrimidinones

A novel iron-containing Schiff base and ionic liquid based bifunctional periodic mesoporous organosilica (Fe@SBIL-BPMO) was prepared, characterized, and its catalytic application was developed. The SBIL-BPMO was first prepared by the grafting of 3-aminopropyltrimethoxysilane on an ionic-liquid-based PMO followed by treatment with 2-hydroxybenzaldehyde in toluene at reflux. This material was then reacted with Fe(NO3)(3)9H(2)O to afford the Fe@BPMO-SBIL nanocatalyst. The catalyst was characterized by thermogravimetric analysis, nitrogen sorption experiments, diffuse reflectance FTIR spectroscopy, low-angle powder XRD, and TEM. The Fe@SBIL-BPMO catalyst was successfully applied in the one-pot synthesis of 3,4-dihydropyrimidinone/thione derivatives under solvent-free reactions. The stability, reactivity, and reusability of the catalyst under the reaction conditions have also been investigated.