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Porous organic frameworks (POFs) are emerging as an important class of porous materials. The absence of functional groups in POFs, however, renders them relatively nonspecific as porous materials for applications such as in heterogeneous chiral catalysis. Although pre- and post-synthetic modifications have been developed for the functionalization of POFs, the introduction of functional groups into POFs remains a great challenge. Herein we have advanced a facile and versatile strategy to uniformly incorporate targeted functional groups into defect porous organic frameworks (dPOFs) by one-pot copolymerization of low-connected functional and primitive multi-connected building blocks. Based on this strategy, four proline-functionalized dPOFs were readily synthesized and developed as new platforms for heterogeneous chiral organocatalysis. The as-prepared dPOFs show higher catalytic activity and superior enantioselectivity than that of their homogeneous counterpart l -proline in the catalytic direct aldol reaction between 4-nitrobenzaldehyde and acetone, and could be reused at least five times without significant loss of catalytic activity and enantioselectivity. [ABSTRACT FROM AUTHOR]

The use of water as reaction medium in the heterogeneous activation of C–H bonds has numerous advantages in terms of environmental benign, safety and cost efficiency impact. However, it is severely hampered because the reactants are difficult to dissolve in water and contact with the active sites of heterogeneous catalysts. Herein, we choose perfluoroalkane-functionalized mesoporous metal-organic framework (MOF) NU-1000 as a hydrophobic platform to encapsulate ultrafine palladium nanoparticles (Pd NPs) for C–H activation in water. The resultant Pd NPs stabilized by the perfluoroalkane exhibited high activity and regioselectivity in the direct C–H arylation of indoles in water. The introduction of perfluoroalkane chains into the mesoporous pores of NU-1000 provides hydrophobic surfaces to facilitate access of the reactants to the active sites to guarantee the high activity. [ABSTRACT FROM AUTHOR]