Homogeneous-like solid base catalysts based on pyridine-functionalized swelling porous polymers

Reported here is the synthesis of pyridine-functionalized porous polymers, which are designed as homogeneous-like base catalysts. These highly porous catalysts have adjustable pyridine contents, high BET surface area (312–649 m2/g), large pore volume (0.5–2.0 cm3/g) and rapid swelling property, thus they efficiently combined the advantage of both homogeneous and heterogeneous catalysts. The exposure degree of active sites in our homogeneous-like catalysts has been evaluated by Cu2+ adsorption, giving similar capacity with homogeneously dissolved poly-4-vinylpyridine. In the Knoevenagel condensation, these materials exhibit excellent activity and stability compared with Mg–Al hydrotalcite and magnesia as well as homogeneous base catalyst of poly-4-vinylpyridine.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► Pyridine-functionalized swelling porous polymers as homogeneous-like base catalysts. ► Combination of the advantages of both homogeneous and heterogeneous catalysts. ► These catalysts exhibit good activity and stability in the Knoevenagel condensation.