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One striking feature of enzyme is its controllable ability to trap substrates via synergistic or cooperative binding in the enzymatic pocket, which renders the shape‐selectivity of product by the confined spatial environment. The success of shape‐selective catalysis relies on the ability of enzyme to tune the thermodynamics and kinetics for chemical reactions. In emulation of enzyme's ability, we showcase herein a targeting strategy with the substrate being anchored on the internal pore wall of metal‐organic frameworks (MOFs), taking full advantage of the sterically kinetic control to achieve shape‐selectivity for the reactions. For this purpose, a series of binding site‐accessible metal metalloporphyrin‐frameworks (MMPFs) have been investigated to shed light on the nature of enzyme‐mimic catalysis. They exhibit a different density of binding sites that are well arranged into the nanospace with corresponding distances of opposite binding sites. Such a structural specificity results in a facile switch in selectivity from an exclusive formation of the thermodynamically stable product to the kinetic product. Thus, the proposed targeting strategy, based on the combination of porous materials and binding events, paves a new way to develop highly efficient heterogeneous catalysts for shifting selectivity. [ABSTRACT FROM AUTHOR]

Tuning catalytic centers in heterogeneous catalyst, both in a chemical and a spatial manner, is a powerful approach to improve the stability and the efficiency of catalysts. While the chemical aspects are largely understood, the spatial interactions around active sites, comprised of non‐covalent interactions, are difficult to maintain and challenging to study. Herein, the unique properties of covalent organic frameworks (COFs) are utilized to establish an ideal reaction environment for the hydrolysis of cellobiose and other common disaccharides in mild, metal‐free, and neutral aqueous conditions. The chosen COF, HCl‐PSA‐IM‐COF‐OMe ("HCl" for hydrochloric acid, "PSA" for propyl sulfonic acid, "IM" for imidazole, and "OMe" for methoxy), is modified to be ultra‐stable in aqueous conditions and possesses sulfonic acid groups for general acid catalysis and for enhanced hydrogen bonding with reactants as well as intraporous chloride anions for oxocarbenium intermediate stabilization. In addition, the system also relies on the differences in adsorptive binding behavior, Kads, of the reactants and the products to the functionalized framework and benefits from a separate physical, kinetic process to boost the catalytic cycle. Due to its stability in aqueous conditions, HCl‐PSA‐IM‐COF‐OMe can be recycled and maintains its hydrolytic properties for five cycles before regeneration is needed. [ABSTRACT FROM AUTHOR]

Asymmetric hydrogenation, a seminal strategy for the synthesis of chiral molecules, remains largely unmet in terms of activation by non‐metal sites of heterogeneous catalysts. Herein, as demonstrated by combined computational and experimental studies, we present a general strategy for integrating rationally designed molecular chiral frustrated Lewis pair (CFLP) with porous metal–organic framework (MOF) to construct the catalyst CFLP@MOF that can efficiently promote the asymmetric hydrogenation in a heterogeneous manner, which for the first time extends the concept of chiral frustrated Lewis pair from homogeneous system to heterogeneous catalysis. Significantly, the developed CFLP@MOF, inherits the merits of both homogeneous and heterogeneous catalysts, with high activity/enantio‐selectivity and excellent recyclability/regenerability. Our work not only advances CFLP@MOF as a new platform for heterogeneous asymmetric hydrogenation, but also opens a new avenue for the design and preparation of advanced catalysts for asymmetric catalysis. [ABSTRACT FROM AUTHOR]

Biomimetic metal‐organic frameworks have attracted great attention as they can be used as bio‐inspired models, allowing us to gain important insights into how large biological molecules function as catalysts. In this work, we report the synthesis and utilization of such a metal‐metalloporphyrin framework (MMPF) that is constructed from a custom‐designed ligand as an efficient halogen bond donor catalyst for Diels–Alder reactions under ambient conditions. The implementation of fabricated halogen bonding capsule as binding pocket with high‐density C−Br bonds enabled the use of halogen bonding to facilitate organic transformations in their three‐dimensional cavities. Through combined experimental and computational studies, we showed that the substrate molecules diffuse through the pores of the MMPF, establishing a host‐guest system via the C−Br⋅⋅⋅π interaction. The formation of halogen bonds is a plausible explanation for the observed boosted catalytic efficiency in Diels–Alder reactions. Moreover, the unique capability of MMPF highlights new opportunities in using artificial non‐covalent binding pockets as highly tunable and selective catalytic materials. [ABSTRACT FROM AUTHOR]

Frustrated Lewis pairs (FLPs) have recently been advanced as efficient metal‐free catalysts for catalytic hydrogenation, but their performance in chemoselective hydrogenation, particularly in heterogeneous systems, has not yet been achieved. Herein, we demonstrate that, via tailoring the pore environment within metal–organic frameworks (MOFs), FLPs not only can be stabilized but also can develop interesting performance in the chemoselective hydrogenation of α,β‐unsaturated organic compounds, which cannot be achieved with FLPs in a homogeneous system. Using hydrogen gas under moderate pressure, the FLP anchored within a MOF that features open metal sites and hydroxy groups on the pore walls can serve as a highly efficient heterogeneous catalyst to selectively reduce the imine bond in α,β‐unsaturated imine substrates to afford unsaturated amine compounds. [ABSTRACT FROM AUTHOR]

Direct use of atmospheric CO2 as a C1 source to synthesize high-value chemicals through environmentally benign processes is of great interest, yet challenging. Porous heterogeneous catalysts that are capable of simultaneously capturing and converting CO2 are promising candidates for such applications. Herein, a family of organic ionic polymers with nanoporous structure, large surface area, strong affinity for CO2, and very high density of catalytic active sites (halide ions) was synthesized through the free-radical polymerization of vinylfunctionalized quaternary phosphonium salts. The resultant porous ionic polymers (PIPs) exhibit excellent activities in the cycloaddition of epoxides with atmospheric CO2, outperforming the corresponding soluble phosphonium salt analogues and ranking among the highest of known metal-free catalytic systems. The high CO2 uptake capacity of the PIPs facilitates the enrichment of CO2 molecules around the catalytic centers, thereby benefiting its conversion. We have demonstrated for the first time that atmospheric CO2 can be directly converted to cyclic carbonates at room temperature using a heterogeneous catalytic system under metal-solvent free conditions. Moreover, the catalysts proved to be robust and fully recyclable, demonstrating promising potential for practical utilization for the chemical fixation of CO2. Our work thereby paves a way to the advance of PIPs as a new type of platform for capture and conversion of CO2. [ABSTRACT FROM AUTHOR]