The emergence of porous organic polymers (POPs) has provided great opportunities for new applications in heterogeneous catalysis owing to their unprecedented intrinsic structural features such as high surface areas, extraordinary framework stabilities and chemically adjustable compositions. In this tutorial review, representative recent developments in the POPs-based catalysts with hierarchically porous structures are presented. Various strategies for the syntheses of hierarchically porous polymers including hard-templating, soft-templating and template-free approaches and the design of catalytically active porous polymers including post-modification, co-polymerization and self-polymerization have been discussed. In addition, their catalytic properties are compared. Finally, we emphasize the importance of the synthesis of hierarchically porous polymer based heterogeneous catalysts using sustainable routes under template-free and metal-free conditions.

A series of diphosphine ligand constructed porous polymers with stable and flexible frameworks have been successfully synthesized under the solvothermal conditions from polymerizing the corresponding vinyl-functionalized diphosphine monomers. These insoluble porous polymers can be swollen by a wide range of organic solvents, showing similar behavior to those of soluble analogues. Rather than just as immobilizing homogeneous catalysts, these porous polymers supported with Rh species demonstrate even better catalytic performance in the hydroformylations than the analogue homogeneous catalysts. The sample extraordinary performance could be attributed to the combination of high ligand concentration and flexible framework of the porous polymers. Meanwhile, they can be easily separated and recycled from the reaction systems without losing any activity and selectivity. This excellent catalytic performance and easy recycling heterogeneous catalyst property make them be very attractive. These diphosphine ligand constructed porous polymers may provide new platforms for the hydroformylation of olefins in the future.

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Porous organic polymers (POPs), which feature high surface areas and designable pore walls, have attracted much attention recently as a result of combining the advantages of both heterogeneous and homogeneous catalysts. Because of the diversity of chemical reactions, one could design polymer frameworks with unique functionalities used as active sites and ligands in catalysis. In the view of green chemistry, this perspective is focused mainly on rational preparation of the porous organic polymers under metal-free conditions and their applications in heterogeneous catalysis. It is observed that many POP-based heterogeneous catalysts demonstrate superior catalytic properties, even better than the homogeneous counterparts. The strategies for designing highly efficient heterogeneous catalysts are briefly assessed.