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Updated: Jun 2, 2026

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Heterogeneous organocatalysis at work: functionalization of hollow periodic mesoporous organosilica spheres with
Jiao Yi Shi1, Chang An Wang, Zhi Jun Li
1State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, PR China.
Abstract:
We report a new method for the synthesis of hollow-structured phenylene-bridged periodic mesoporous organosilica (PMO) spheres with a uniform particle size of 100-200 nm using α-Fe(2)O(3) as a hard template. Based on this method, the hollow-structured phenylene PMO could be easily functionalized with MacMillan catalyst (H-PhPMO-Mac) by a co-condensation process and a "click chemistry" post-modification. The synthesized H-PhPMO-Mac catalyst has been found to exhibit high catalytic activity (98% yield, 81% enantiomeric excess (ee) for endo and 81% ee for exo) in asymmetric Diels-Alder reactions with water as solvent. The catalyst could be reused for at least seven runs without a significant loss of catalytic activity. Our results have also indicated that hollow-structured PMO spheres exhibit higher catalytic efficiency than solid (non-hollow) PMO spheres, and that catalysts prepared by the co-condensation process and "click chemistry" post-modification exhibit higher catalytic efficiency than those prepared by a grafting method.
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