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-Fe2O3 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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