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The precise regulation of single‐atom catalysts (SACs) with the desired local chemical environment is vital to elucidate the relationship between the SACs structure and the catalytic performance. The debate on the effect of the local coordination environment is quite complicated even for the SACs with the same composition and chemical nature, calling for increased attention on the regulation of the second coordination shell. For oxide‐supported SACs, it remains a significant challenge to precisely manipulate the second coordination shell of single atoms supported on oxides due to the structural robustness of oxides. Here, Ir single atoms were anchored on NiO supports via different bonding strategies, resulting in the diverse Ir−O−Ni coordination numbers for Ir sites. Specifically, Ir1/NiO, Ir1−NiO, and Ir1@NiO SACs with increasing Ir−O−Ni coordination numbers of 3, 4, and 5 were synthesized, respectively. We found that the activity of the three samples towards oxygen evolution reaction (OER) exhibited a volcano‐shaped relationship with the Ir−O−Ni coordination number, with Ir1−NiO showing the lowest overpotential of 225 mV at 10 mA cm−2. Mechanism investigations indicate that the moderate coordination number of Ir−O−Ni in Ir1−NiO creates the higher occupied Ir dz2 orbital, weakening the adsorption strength for *OOH intermediates and thereby enhancing the OER activity. [ABSTRACT FROM AUTHOR]

Persistent challenges in hydroformylation of olefins include controlling regioselectivity, particularly for short aliphatic olefins and conducting reactions under ambient conditions. We report here the synthesis of monophosphine–Rh complexes on a typical chelated diphosphine ligand mediated by a Zr‐MOF through isolating a pair of phosphorus atoms. We demonstrate that single‐crystal X‐ray diffraction can elucidate the structural transformation of the Rh catalyst during olefin hydroformylation, providing valuable information on active site reconstruction during catalysis. The Rh‐MOF catalyst demonstrates excellent catalytic and recyclable performance in the hydroformylation of short aliphatic olefins with linear to branched ratios of up to 99 : 1. Due to the framework's capacity to adsorb and concentrate gases, the catalytic reactions occur under room temperature and pressure, eliminating the need for the high temperature and pressures typically required in homogeneous systems. This study show that Zr–MOF can be a unique platform for synthesizing unusual catalytic species that cannot exist in solutions for meaningful chemical transformations and elucidate valuable structural information pertaining to metal‐based catalysis. [ABSTRACT FROM AUTHOR]

Supramolecular assembly frameworks (SAFs) represent a new category of porous materials, utilizing non‐covalent interactions, setting them apart from metal–organic frameworks (MOFs) and covalent organic frameworks (COFs). This category includes but is not restricted to hydrogen‐bonded organic frameworks and supramolecular organic frameworks. SAFs stand out for their outstanding porosity, crystallinity, and stability, alongside unique dissolution‐recrystallization dynamics that enable significant structural and functional modifications. Crucially, their non‐covalent assembly strategies allow for a balanced manipulation of porosity, symmetry, crystallinity, and dimensions, facilitating the creation of advanced crystalline porous materials unattainable through conventional covalent or coordination bond synthesis. Despite their considerable promise in overcoming several limitations inherent to MOFs and COFs, particularly in terms of solution‐processability, SAFs have received relatively little attention in recent literature. This Minireview aims to shed light on standout SAFs, exploring their design principles, synthesis strategies, and characterization methods. It emphasizes their distinctive features and the broad spectrum of potential applications across various domains, aiming to catalyze further development and practical application within the scientific community. [ABSTRACT FROM AUTHOR]

Covalent polymerization of organic molecules into crystalline one‐dimensional (1D) polymers is effective for achieving desired thermal, optical, and electrical properties, yet it remains a persistent synthetic challenge for their inherent tendency to adopt amorphous or semicrystalline phases. Here we report a strategy to synthesize crystalline 1D covalent organic frameworks (COFs) composing quasi‐conjugated chains with benzoxazine linkages via the one‐pot Mannich reaction. Through [4+2] and [2+2] type Mannich condensation reactions, we fabricated stoichiometric and sub‐stoichiometric 1D covalent polymeric chains, respectively, using doubly and singly linked benzoxazine rings. The validity of their crystal structures has been directly visualized through state‐of‐the‐art cryogenic low‐dose electron microscopy techniques. Post‐synthetic functionalizations of them with a chiral MacMillan catalyst produce crystalline organic photocatalysts that demonstrated excellent catalytic and recyclable performance in light‐driven asymmetric alkylation of aldehydes, affording up to 94 % enantiomeric excess [ABSTRACT FROM AUTHOR]

During multivalent ions insertion processes, intense electrostatic interaction between charge carriers and host makes the high‐performance reversible Al3+ storage remains an elusive target. On account of the strong electrostatic repulsion and poor robustness, Prussian Blue analogues (PBAs) suffer severely from the inevitable and large strain and phase change during reversible Al3+ insertion. Herein, we demonstrate an entropy‐driven strategy to realize ultralong life aqueous Al‐ion batteries (AIBs) based on medium entropy PBAs (ME‐PBAs) host. By multiple redox active centers introduction, the intrinsic poor conductivity can be enhanced simultaneously, resulting in outstanding capabilities of electrochemical Al3+ storage. Meanwhile, the co‐occupation at metal sites in PBA frameworks can also increase the M−N bond intensity, which is beneficial for constraining the phase change during consecutive Al3+ reversible insertion, to realize an extended lifespan over 10,000 cycles. Based on the calculation at different operation states, the fluctuation of ME‐PBA lattice parameters is only 1.2 %. Assembled with MoO3 anodes, the full cells can also deliver outstanding electrochemical properties. The findings highlight that, the entropy regulation strategy could uncover the isochronous constraint on both strain and phase transition for long‐term reversible Al3+ storage, providing a promising design for advanced electrode materials for aqueous multivalent ions batteries. [ABSTRACT FROM AUTHOR]

Bridged benzazepine scaffolds, possessing unique structural and physicochemical activities, are widespread in various natural products and drugs. The construction of these skeletons often requires elaborate synthetic effort with low efficiency. Herein, we develop a simple and divergent approach for constructing various bridged benzazepines by a photocatalytic intermolecular dearomatization of naphthalene derivatives with readily available α‐amino acids. The bridged motif is created via a cascade sequence involving photocatalytic 1,4‐hydroaminoalkylation, alkene isomerization and cyclization. Interestingly, the diastereoselectivity can be regulated through different reaction modes in the cyclization step. Moreover, aminohydroxylation and its further bromination have also been demonstrated to access highly functionalized bridged benzazepines. Preliminary mechanistic studies have been performed to get insights into the mechanism. This method provides a divergent synthetic approach for construction of highly functionalized bridged benzazepines, which have been otherwise difficult to access. [ABSTRACT FROM AUTHOR]

Construction of supramolecular structures with internal functionalities is a promising approach to build enzyme‐like cavities. The endo‐functionalized [Pd12L24] and [Pd2L4] coordination cages represent the most successful systems in this regard. However, these systems mainly contain one type of endo‐moiety. We herein provide a solution for the controlled endo‐functionalization of [Pd2L4] cages. Site‐selective introduction of the endo‐functional group was achieved through the formation of heteroleptic [Pd2(LA)2(LB)(LC)] cages. Using two orthogonal steric control elements is the key for the selective formation of the hetero‐assemblies. We demonstrated the construction of two hetero‐cages with a single internal functional group as well as a hetero‐cage with two distinct endohedral functionalities. The endo‐functionalized hetero‐cages bound sulfonate guests with fast‐exchange dynamics. This strategy provides a new solution for the controlled endo‐functionalization of supramolecular cavities. [ABSTRACT FROM AUTHOR]

Nucleic acid (NA) computation has been widely developed in the past years to solve kinds of logic and mathematic issues in both information technologies and biomedical analysis. However, the difficulty to integrate non‐NA molecules limits its power as a universal platform for molecular computation. Here, we report a versatile prototype of hybridized computation integrated with both nucleic acids and non‐NA molecules. Employing the conformationally controlled ligand converters, we demonstrate that non‐NA molecules, including both small molecules and proteins, can be computed as nucleic acid strands to construct the circuitry with increased complexity and scalability, and can be even programmed to solve arithmetical calculations within the computational nucleic acid system. This study opens a new door for molecular computation in which all‐NA circuits can be expanded with integration of various ligands, and meanwhile, ligands can be precisely programmed by the nuclei acid computation. [ABSTRACT FROM AUTHOR]

Chiral imidodiphosphates (IDPs) have emerged as strong Brønsted acid catalysts for many enantioselective processes. However, the dynamic transformation between O,O‐syn and O,O‐anti conformers typically results in low enantioselectivity. Here we demonstrate that topologies of metal‐organic frameworks (MOFs) can be exploited to control IDP conformations and local chiral microenvironments for enantioselective catalysis. Two porous Dy‐MOFs with different topologies are obtained from an enantiopure 1,1′‐biphenol IDP‐based tetracarboxylate ligand. While the ligand adopts a 4‐ or 3‐connected (c) binding mode, all IDPs are rigidified to get only a single O,O‐syn conformation and display greatly enhanced Brønsted acidity relative to the free IDP. The MOF with the 4‐c IDP that has a relatively less compact shape than the 3‐c IDP can be an efficient and recyclable heterogeneous Brønsted acid catalysing the challenging asymmetric O,O‐acetalization reaction with up to 96 % enantiomeric excess. [ABSTRACT FROM AUTHOR]

A versatile terpene synthase (LcTPS2) producing unconventional macrocyclic terpenoids was characterized from Leucosceptrum canum. Engineered Escherichia coli and Nicotiana benthamiana expressing LcTPS2 produced six 18‐/14‐membered sesterterpenoids including five new ones and two 14‐membered diterpenoids. These products represent the first macrocyclic sesterterpenoids from plants and the largest sesterterpenoid ring system identified to date. Two variants F516A and F516G producing approximately 3.3‐ and 2.5‐fold, respectively, more sesterterpenoids than the wild‐type enzyme were engineered. Both 18‐ and 14‐membered ring sesterterpenoids displayed significant inhibitory activity on the IL‐2 and IFN‐γ production of T cells probably via inhibition of the MAPK pathway. The findings will contribute to the development of efficient biocatalysts to create bioactive macrocyclic sesterterpenoids, and also herald a new potential in the well‐trodden territory of plant terpenoid biosynthesis. [ABSTRACT FROM AUTHOR]

Electroreduction of CO2 to CO is a promising approach for the cycling use of CO2, while it still suffers from impractical current density and durability. Here we report a single‐atom nanozyme (Ni−N5−C) that achieves industrial‐scale performance for CO2‐to‐CO conversion with a Faradaic efficiency (FE) exceeded 97 % over −0.8–−2.4 V vs. RHE. The current density at −2.4 V vs. RHE reached a maximum of 1.23 A cm−2 (turnover frequency of 69.7 s−1) with an FE of 99.6 %. No obvious degradation was observed over 100 hours of continuous operation. Compared with the planar Ni−N4 site, the square‐pyramidal Ni−N5 site has an increase and a decrease in the dz2 ${{{\rm d}}_{{z}^{2}}}$ and dxz/yz orbital energy levels, respectively, as revealed by density functional theory calculations. Thus, the Ni−N5 catalytic site is more superior to activate CO2 molecule and reduce the energy barriers as well as promote the CO desorption, thus boosting the kinetic activation process and catalytic activity. [ABSTRACT FROM AUTHOR]

Tandem catalysts can divide the reaction into distinct steps by local multiple sites and thus are attractive to trigger CO2RR to C2+ products. However, the evolution of catalysts generally exists during CO2RR, thus a closer investigation of the reconstitution, interplay, and active origin of dual components in tandem catalysts is warranted. Here, taking AgI−CuO as a conceptual tandem catalyst, we uncovered the interaction of two phases during the electrochemical reconstruction. Multiple operando techniques unraveled that in situ iodine ions leaching from AgI restrained the entire reduction of CuO to acquire stable active Cu0/Cu+ species during the CO2RR. This way, the residual iodine species of the Ag matrix accelerated CO generation and iodine‐induced Cu0/Cu+ promotes C−C coupling. This self‐adaptive dual‐optimization endowed our catalysts with an excellent C2+ Faradaic efficiency of 68.9 %. Material operando changes in this work offer a new approach for manipulating active species towards enhancing C2+ products. [ABSTRACT FROM AUTHOR]

Pd‐based molecular square Pd4L4 and triangle Pd3L3 represent the molecular ancestors of metal‐coordination polyhedra that have been an integral part of the field for the last 30 years. Conventional solution‐based reactions between cis‐protected Pd ions and 2,2′‐bipyridine exclusively give Pd4L4 and/or Pd3L3 as the sole products. We herein show that, under solvent‐free mechanochemical conditions, the self‐assembly energy landscape can be thermodynamically manipulated to form an elusive cyclic dimer Pd2L2 for the first time. In the absence of solvent, Pd2L2 is indefinitely stable in the solid‐state, but converts rapidly to its thermodynamic products Pd3L3 and Pd4L4 in solution, confirming Pd2L2 as a short‐lived kinetic species in the solution‐based self‐assembly process. Our results highlight how mechanochemistry grants access to a vastly different chemical space than available under conventional solution conditions. This provides a unique opportunity to isolate elusive species in self‐assembly processes that are too reactive to both "see" and "capture". [ABSTRACT FROM AUTHOR]

Pd‐based molecular square Pd4L4 and triangle Pd3L3 represent the molecular ancestors of metal‐coordination polyhedra that have been an integral part of the field for the last 30 years. Conventional solution‐based reactions between cis‐protected Pd ions and 2,2′‐bipyridine exclusively give Pd4L4 and/or Pd3L3 as the sole products. We herein show that, under solvent‐free mechanochemical conditions, the self‐assembly energy landscape can be thermodynamically manipulated to form an elusive cyclic dimer Pd2L2 for the first time. In the absence of solvent, Pd2L2 is indefinitely stable in the solid‐state, but converts rapidly to its thermodynamic products Pd3L3 and Pd4L4 in solution, confirming Pd2L2 as a short‐lived kinetic species in the solution‐based self‐assembly process. Our results highlight how mechanochemistry grants access to a vastly different chemical space than available under conventional solution conditions. This provides a unique opportunity to isolate elusive species in self‐assembly processes that are too reactive to both "see" and "capture". [ABSTRACT FROM AUTHOR]

The direct functionalization of inert C(sp3)−H bonds under environmentally benign catalytic conditions remains a challenging task in synthetic chemistry. Here, we report an organocatalytic remote C(sp3)−H acylation of amides and cascade cyclization through a radical‐mediated 1,5‐hydrogen atom transfer mechanism using N‐heterocyclic carbene as the catalyst. Notably, a diversity of nitrogen‐containing substrates, including simple linear aliphatic carbamates and ortho‐alkyl benzamides, can be successfully applied to this organocatalytic system. With the established protocol, over 120 examples of functionalized δ‐amino ketones and isoquinolinones with diverse substituents were easily synthesized in up to 99 % yield under mild conditions. The robustness and generality of the organocatalytic strategy were further highlighted by the successful acylation of unactivated C(sp3)−H bonds and late‐stage modification of pharmaceutical molecules. Then, the asymmetric control of the radical reaction was attempted and proven feasible by using a newly designed chiral thiazolium catalyst, and moderate enantioselectivity was obtained at the current stage. Preliminary mechanistic investigations including several control reactions, KIE experiments, and computational studies shed light on the organocatalytic radical reaction mechanism. [ABSTRACT FROM AUTHOR]