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Heterogeneous microporous acid (sulfonic acid) and base (benzylamine) catalysts with high surface areas were synthesized using simple aromatic compounds through one-step external cross-linking reaction. The direct induction and control of catalytic sites were achieved by functionalized monomers using an appropriate amount of acid/base monomers. This strategy provides an easy approach to produce highly stable and acid/base functionalized microporous organic polymers. The structure and composition of the catalysts were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen sorption, Fourier transform infrared spectroscopy (FT-IR), solid-state 13 C cross polarization magic angle spinning (CP/MAS) NMR, thermogravimetric analysis (TGA), and element mapping analysis. The stable porous skeleton and the accurate manipulation of the catalyst structure allowed us to use the obtained polymers as compatible and efficient acid/base co-catalysts for one-pot cascade reactions. We demonstrated the use of these microporous heterogeneous catalysts for the cascade deacetalization/Henry and deacetalization/Knoevenagel reactions. The results demonstrated that preparing microporous materials from simple aromatic compounds through one-step external cross-linking reaction is indeed a cost-effective and easy-to-handle method to produce functionalized heterogeneous catalysts. The microporous heterogeneous catalysts produced by this method are highly stable and the amount of catalytically active sites can easily be controlled to form a catalytic system with two antagonistic centers. [ABSTRACT FROM AUTHOR]

• Hypercrosslinked polymers with abundant CO 2 chemisorption sites were prepared. • Moderate chemisorption effect on CO 2 with high Qst value of 34.7 kJ/mol. • The porous catalysts exhibit excellent CO 2 chemical conversion efficiency. • The porous catalysts show good stability for the cycloaddition reaction. The weak physical adsorption of CO 2 in porous organic polymers (POPs) leads to the low utilization of CO 2 in catalysis, calling for the need to develop materials to ensure higher adsorption of CO 2 to achieve high conversion efficiency. In this regard, hydrazine (HZ) was successfully introduced into metalloporphyrin-based hypercrosslinked polymers (HCPs) by post-modification to create abundant CO 2 chemisorption sites in structures for efficient adsorption (Qst value up to 34.7 kJ/mol) and chemical conversion of CO 2 under ambient conditions. The HZ-modified material (HCP-TPP-Co-HZ) exhibits high catalytic performance for different molecular sizes of epoxide substrates with excellent yields (reaching 98 % of propylene oxide), much superior than that of HCP-TPP-Co-SO 3 H (64 %), which can be ascribed to the abundant chemisorption sites for CO 2 reactants. Moreover, HCP-TPP-Co-HZ has good stability and shows excellent recycling performance (more than 5 times) for the coupling of CO 2 with substituted epoxides at room temperature and atmospheric pressure. This strategy to introduce amine groups as CO 2 chemisorption sites has been demonstrated to be a new pathway for the design of efficient HCPs catalysts for chemical conversion of CO 2. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) is one of the best candidates to replace current petroleum energy resources due to its rich abundance and clean combustion. However, the storage of H2 presents a major challenge. There are two methods for storing H2 fuel, chemical and physical, both of which have some advantages and disadvantages. In physical storage, highly porous organic polymers are of particular interest, since they are low cost, easy to scale up, metal-free, and environmentally friendly. In this review, highly porous polymers for H2 fuel storage are examined from five perspectives: (a) brief comparison of H2 storage in highly porous polymers and other storage media; (b) theoretical considerations of the physical storage of H2 molecules in porous polymers; (c) H2 storage in different classes of highly porous organic polymers; (d) characterization of microporosity in these polymers; and (e) future developments for highly porous organic polymers for H2 fuel storage. These topics will provide an introductory overview of highly porous organic polymers in H2 fuel storage. [ABSTRACT FROM AUTHOR]