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Metal-organic frameworks (MOFs) have great prospects as adsorbents for industrial gas purification, but often suffer from issues of water stability and competitive water adsorption. Herein, we present a hydrolytically stable MOF that could selectively capture and recover trace SO 2 from flue gas, and exhibits remarkable recyclability in the breakthrough experiments under wet flue-gas conditions, due to its excellent resistance to the corrosion of SO 2 and the water-derived capillary forces. More strikingly, its SO 2 capture efficiency is barely influenced by the increasing humidity, even if the pore filling with water is reached. Mechanistic studies demonstrate that the delicate pore structure with diverse pore dimensions and chemistry leads to different adsorption kinetics and thermodynamics as well as segregated adsorption domains of SO 2 and H 2 O. Significantly, this non-competitive adsorption mechanism enables simultaneous desulfurization and dehydration by a single adsorbent, opening an avenue toward cost-effective and simplified processing flowcharts for flue gas purification., (© 2024 Wiley-VCH GmbH.)

The adsorptive separation of molecules with very similar physical properties is always a challenging task. Reported herein is the design and tailoring of zeolite adsorbent for the precise discrimination and separation of CO 2 -C 2 H 2 mixture through the pronounced trapdoor effect. Typically, Sr exchanged K-type clinoptilolite, namely Sr/K-HEU, is developed as a robust zeolite adsorbent for inverse CO 2 -C 2 H 2 separation, showing the-state-of-the-art dynamic CO 2 /C 2 H 2 selectivity of 48.0 and sustainable CO 2 dynamic uptake of 0.96 mmol/g at the same time. The perfect recyclability and the intrinsic low-cost nature of Sr/K-HEU make it a promising candidate for practical applications. Three-dimensional electron diffraction determines the precise structure of Sr/K-HEU and density functional theory calculations reveal the intricate interplay between guest molecules and the gate-keeping extraframework cations. Briefly, extraframework Sr 2+ cations from the ten-membered rings of HEU zeolites act as the molecular trapdoor, allowing the entry of CO 2 molecules while excluding C 2 H 2 . This work presents a new example of molecular trapdoor in zeolite and its successful application in the challenging inverse CO 2 -C 2 H 2 separation, which not only expands the scope of molecular trapdoor concept but also improves current understanding on the nature of molecular trapdoor., (© 2024 Wiley-VCH GmbH.)

Porous Organic Cages (POCs) have gathered a lot of attention in sorts of fields. Previous studies often focused on the functionalization of their intrinsic porosity, while the utilization of the extrinsic porosity has been seldom reported. To date, the rational construction of functionalized extrinsic porosity in POCs is a serious challenge, which still relies on trial and error. Inspired by hydrophobic proteins, in the contribution, a POC (namely NKPOC-DS) is obtained with hydrophobic "intermolecular pocket" as extrinsic porosity constructed through the assembly of disulfide bonds with hydrophobic groups, facilitating strong supramolecular interactions as confirmed by Electrostatic Potential (ESP) maps and single-crystal X-ray diffraction analysis. Notably, NKPOC-DS exhibits a unique C 2 H 6 -selective "breathing behaviour" due to the presence of softness in its extrinsic porosity, which does not extend to other gases such as C 2 H 4 , CH 4 , CO 2 , N 2 , and H 2 . Such specific recognition of C 2 H 6 thus provides NKPOC-DS with the ability to preferentially adsorb C 2 H 6 from a C 2 H 6 /C 2 H 4 mixture. The innovative approach of biomimicry in the design of functional POCs provides new insights into manipulating the packing of cages, paving the way for potential applications in guest recognition and adsorption separations., (© 2024 Wiley-VCH GmbH.)

Infrared (IR) transparent polymer materials prepared by inverse vulcanization, as a promising candidate to replace inorganic materials, are new materials for constructing key devices in IR optics. However, it is difficult to achieve a balance between infrared optical and thermal properties in polymers due to the intrinsic infrared absorption of organic materials. Herein, our strategy is to construct a high boiling point symmetrical molecular norbornadiene derivative cross-linking agent (DMMD) which can be inverse vulcanized with molten sulfur, and obtain Poly (S-r-DMMD) with different sulfur content by controlling the feed ratio of sulfur. With the rigid core and low IR activity in DMMD, the prepared polymers exhibit tunable thermal properties (T g : 98.3-119.8 °C) and high IR transmittance (medium-wave infrared region (MWIR): 42.9-52.6 %; long-wave infrared region (LWIR): 1.5-5.29 %). In addition, Poly (S-r-DMMD) can be used to prepare large-size free-standing Fresnel lenses for IR imaging by simple hot-pressing, which provides flexibility in the design and production of IR fine lenses. This study provides a novel strategy for balancing the thermal and optical properties of IR transparent polymer materials, while providing relevant references for balancing the IR optical and thermal properties of polymer materials., (© 2024 Wiley-VCH GmbH.)

Chiral sulfones are recurrent motifs in pharmaceuticals and bioactive molecules. Although chemical methods have been developed to afford α- or β- chiral sulfones, these protocols rely heavily on the pre-synthesis of structurally complicated starting materials and chiral metal complexes. Herein, we described a photoenzymatic approach for the radical-mediated stereoselective hydrosulfonylation. Engineered variants of ene reductases provide efficient biocatalysts for this transformation, enabling to achieve a series of β-chiral sulfonyl compounds with high yields (up to 92 %) and excellent e.r. values (up to 99 : 1)., (© 2023 Wiley-VCH GmbH.)

All-solid-state Z-Scheme photocatalysts have attracted significant attention due to their great potential for solar fuel production. However, delicately coupling two individual semiconductors with a charge shuttle by a material strategy remains a challenge. Herein, we demonstrate a new protocol of natural Z-Scheme heterostructures by strategically engineering the component and interfacial structure of red mud bauxite waste. Advanced characterizations elucidated that the hydrogen-induced formation of metallic Fe enabled the effective Z-Scheme electron transfer from γ-Fe 2 O 3 to TiO 2 , leading to the significantly boosted spatial separation of photo-generated carriers for overall water splitting. To the best of our knowledge, it is the first Z-Scheme heterojunction based on natural minerals for solar fuel production. Thus our work provides a new avenue toward the utilization of natural minerals for advanced catalysis applications., (© 2023 Wiley-VCH GmbH.)

Solid-state lithium-metal batteries are considered as the next generation of high-energy-density batteries. However, their solid electrolytes suffer from low ionic conductivity, poor interface performance, and high production costs, restricting their commercial application. Herein, a low-cost cellulose acetate-based quasi-solid composite polymer electrolyte (C-CLA QPE) was developed with a high Li +  transference number (tLi+) of 0.85 and excellent interface stability. The prepared LiFePO 4  (LFP)|C-CLA QPE|Li batteries exhibited excellent cycle performance with a capacity retention of 97.7% after 1200 cycles at 1 C and 25℃. The experimental results and Density Function Theory (DFT) simulation revealed that the partially esterified side groups in the CLA matrix contribute to the migration of Li +  and enhance electrochemical stability. This work provides a promising strategy for fabricating cost-effective, stable polymer electrolytes for solid-state lithium batteries., (© 2023 Wiley-VCH GmbH.)

Lanthanide metal-organic frameworks (Ln-MOFs) are promising for luminescence detection of volatile organic compound (VOC) vapors, but usually suffer from the silent or quenched Ln 3+ emission. Herein, we report a new dual-emissive Eu-MOF composed of the coordinatively unsaturated Eu 9 clusters that afford abundant open metal sites to form a confined "binding pocket" to facilitate the preconcentration and recognition of VOCs. Single-crystal structural analyses reveal that specific analytes can replace the OH oscillators in the first coordination sphere of Eu 3+ and form a unique hydrogen-bonding second-sphere adduct tying adjacent Eu 9 clusters together to minimize their nonradiative vibrational decay. With the promoted Eu 3+ luminescence, the MOF realizes real-time in situ visual sensing of THF vapor (<1 s) and shows a quantitative ratiometric response to the vapor pressure with a limit of detection down to 17.33 Pa. Also, it represents a top-performing ratiometric luminescent thermometer., (© 2022 Wiley-VCH GmbH.)

Carbene insertion reactions initiated with diazo compounds have been widely used to develop unnatural enzymatic reactions. However, alternative functionalization of diazo compounds in enzymatic processes has been unexploited. Herein, we describe a photoenzymatic strategy for radical-mediated stereoselective hydroalkylation with diazo compounds. This method generates carbon-centered radicals through an ene reductase catalyzed photoinduced electron transfer process from diazo compounds, enabling the synthesis of γ-stereogenic carbonyl compounds in good yields and stereoselectivities. This study further expands the possible reaction patterns in photo-biocatalysis and offers a new approach to solving the selectivity challenges of radical-mediated reactions., (© 2022 Wiley-VCH GmbH.)

The development of mild, efficient, and enantioselective methods for preparing chiral fluorinated compounds has been a long-standing challenge. Herein, we report a promiscuous cyclohexanone monooxygenase (CHMO) for the photoinduced synthesis of chiral α-fluoroketones via enantioselective reductive dehalogenation of α,α-halofluoroketones. Wild-type CHMO from Acinetobacter sp. possesses this promiscuous ability innately; however, the yield and stereoselectivity are low. A structure-guided rational design of CHMO improved the yield and stereoselectivity remarkably. Mechanistic studies and molecular simulations demonstrated that this photoinduced CHMO catalyzes the reductive dehalogenation via a novel electron transfer (ET)/proton transfer (PT) mechanism, distinct from that of previously reported reductases with similar promiscuity. This methodology was expanded to various substrates, and desirable chiral α-fluoroketones were obtained in high yields (up to 99 %) and e.r. values (up to 99:1)., (© 2022 Wiley-VCH GmbH.)

The elusive plumbylone {[Si II (Xant)Si II ]Pb 0 } 3 stabilized by the bis(silylene)xanthene chelating ligand 1, [Si II (Xant)Si II =PhC(NtBu) 2 Si(Xant)Si(NtBu) 2 CPh], and its isolable carbonyl iron complex {[Si II (Xant)Si II ]Pb 0 Fe(CO) 4 } 4 are reported. The compounds 3 and 4 were obtained stepwise via reduction of the lead(II) dibromide complex {[Si II (Xant)Si II ]PbBr 2 } 2, prepared from the bis(silylene)xanthene 1 and PbBr 2 , employing potassium naphthalenide and K 2 Fe(CO) 4 , respectively. While the genuine plumbylone 3 is rather labile even at -60 °C, its Pb 0 →Fe(CO) 4 complex 4 turned out to be relatively stable and bottleable. However, solutions of 4 decompose readily to elemental Pb and {[Si II (Xant)Si II ]Fe(CO) 3 } 5 at 80 °C. Reaction of 4 with [Rh(CO) 2 Cl] 2 leads to the formation of the unusual dimeric [(OC) 2 RhPb(Cl)Fe(CO) 4 ] complex 6 with trimetallic Rh-Pb-Fe bonds. The molecular and electronic structures of 3 and 4 were established by Density Functional Theory (DFT) calculations., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Developing universal stimuli-responsive materials capable of emitting a broad spectrum of colors is highly desirable. Herein, we deliberately grafted a conformation-adaptable organic chromophore into the established coordination space of a flexible metal-organic framework (MOF). In terms of the coupled structural transformations and the space confinement, the chromophore in the MOF matrix underwent well-regulated conformational changes under physical and chemical stimuli, simultaneously displaying thermo-, piezo-, and solvato-fluoro-chromism with color tunability over the visible range. Owing to the resilient nature and the reduced dimensionality of the selected coordination space, all three color modulations behaved in a sensitive and self-reversible manner, each following a linear correlation of the emission maximum with stimulus. Single-crystal X-ray diffraction of the variable-temperature structures and solvent-inclusion crystals elucidated the intricate color varying mechanisms., (© 2022 Wiley-VCH GmbH.)

The monoatomic zero-valent tin complex (stannylone) {[Si II (Xant)Si II ]Sn 0 } 5 stabilized by a bis(silylene)xanthene ligand, [Si II (Xant)Si II =PhC(NtBu) 2 Si(Xant)Si(NtBu) 2 CPh], and its bis-tetracarbonyliron complex {[Si II (Xant)Si II ]Sn 0 [Fe(CO) 4 ] 2 } 4 are reported. The stannylone 5 bearing a two-coordinate zero-valent tin atom is synthesized by reduction of the precursor 4 with potassium graphite. Compound 4 results from the Sn II halide precursor {[Si II (Xant)Si II ]Sn II Cl}Cl 2 or {[Si II (Xant)Si II ]SnBr 2 } 3 through reductive salt-metathesis reaction with K 2 Fe(CO) 4 . According to density functional theory (DFT) calculations, the highest occupied molecular orbital (HOMO) and HOMO-1 of 5 correspond to a π-type lone pair with delocalization into both adjacent vacant orbitals of the Si II atoms and a σ-type lone pair at the Sn 0 center, respectively, indicating genuine stannylone character., (© 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Due to the high risk of heart disease caused by the intake of trans fatty acids, a method to eliminate trans fatty acids from foods has become a critical issue. Herein, we engineered fatty acid photo-decarboxylase from Chlorella variabilis (CvFAP) to selectively catalyze the decarboxylation of trans fatty acids to yield readily-removed hydrocarbons and carbon dioxide, while cis fatty acids remained unchanged. An efficient protein engineering based on FRISM strategy was implemented to intensify the electronic interaction between the residues and the double bond of the substrate that stabilized the binding of elaidic acid in the channel. For the model compounds, oleic acid and elaidic acid, the best mutant, V453E, showed a one-thousand-fold improvement in the trans-over-cis (ToC) selectivity compared with wild type (WT). As the first report of the direct biocatalytic decarboxylation resolution of trans/cis fatty acids, this work offers a safe, facile, and eco-friendly process to eliminate trans fatty acids from edible oils., (© 2021 Wiley-VCH GmbH.)

The reliable design and prediction of enzyme promiscuity to access transformations not observed in nature remains a long-standing challenge. Herein, we present the first example of an intramolecular stereoselective Stetter reaction catalyzed by benzaldehyde lyase, guided by the rational structure screening of various ThDP-dependent enzymes using molecular dynamics (MD) simulations. After optimization, high productivity (up to 99 %) and stereoselectivity (up to 99:1 e.r.) for this novel enzyme function was achieved., (© 2021 Wiley-VCH GmbH.)

A cyclic (R 2 SnAu) 3 anion (3 - , R 2 Sn=2,2,5,5-tetrakis(trimethylsilyl)-1-stannacyclopentane-1,1-diyl) has been synthesized as a stable blue salt with K + (THF) 6 through the reaction of stable dialkylstannylene 1 with R' 3 PAuCl (R'=Et, Ph) followed by the reduction with KC 8 . Crystallographic and NMR analysis shows that the six-membered (SnAu) 3 ring of 3 - is planar and highly symmetric with an equal distance of six Au-Sn bonds. A UV/Vis spectrum of 3 - in hexane reveals an intense absorption maximum at 598 nm. While cyclic Au 3 - with four valence electrons is known as unstable anti-aromatic anion, 3 - with three divalent tin ligands is stable σ aromatic anion with an unprecedented Möbius orbital array as predicted by the perturbation MO and CCSD analysis of 3 - ., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Cyclohexanone monooxygenases (CHMOs) show very high catalytic specificity for natural Baeyer-Villiger (BV) reactions and promiscuous reduction reactions have not been reported to date. Wild-type CHMO from Acinetobacter sp. NCIMB 9871 was found to possess an innate, promiscuous ability to reduce an aromatic α-keto ester, but with poor yield and stereoselectivity. Structure-guided, site-directed mutagenesis drastically improved the catalytic carbonyl-reduction activity (yield up to 99 %) and stereoselectivity (ee up to 99 %), thereby converting this CHMO into a ketoreductase, which can reduce a range of differently substituted aromatic α-keto esters. The improved, promiscuous reduction activity of the mutant enzyme in comparison to the wild-type enzyme results from a decrease in the distance between the carbonyl moiety of the substrate and the hydrogen atom on N5 of the reduced flavin adenine dinucleotide (FAD) cofactor, as confirmed using docking and molecular dynamics simulations., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Although great achievements have been made in the synthesis of giant lanthanide clusters, novel structural models are still scarce. Herein, we report a giant lanthanide cluster Dy 76 , constructed from [Dy 3 (μ 3 -OH) 4 ] and [Dy 5 (μ 4 -O)(μ 3 -OH) 8 ] building blocks. As the largest known Dy cluster, the structure of Dy 76 can be seen as arising from the fusion of two Dy 48 clusters; these clusters can be isolated under various synthetic conditions and were characterized by single-crystal X-ray diffraction. This new, fused structural model of the pillar motif has not been found in Ln clusters. Furthermore, the successful conversion of Dy 76 back into Dy 48 in a retrosynthetic manner supports the proposed fusion formation mechanism of Dy 76 . Electrospray ionization mass spectrometry (ESI-MS) analysis suggests that the metal cluster skeleton of Dy 76 shows good stability in various solvents. This work not only reveals a new structural type of Ln clusters but also provides insight into the novel fusion assembly process., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Chiral α-functionalized carboxylic acids are valuable precursors for a variety of medicines and natural products. Herein, we described an engineered fatty acid photodecarboxylase (CvFAP)-catalyzed kinetic resolution of α-amino acids and α-hydroxy acids, which provides the unreacted R-configured substrates with high yields and excellent stereoselectivity (ee up to 99 %). This efficient light-driven process requires neither NADPH recycling nor prior preparation of esters, which were required in previous biocatalytic approaches. The structure-guided engineering strategy is based on the scanning of large amino acids at hotspots to narrow the substrate binding tunnel. To the best of our knowledge, this is the first example of asymmetric catalysis by an engineered CvFAP., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We herein report a new coordination network that deforms in a smooth and reversible manner under either thermal or pressure stimulation. Concomitantly, the organic fluorophores coordinatively bound to the channel in a face-to-face arrangement respond to this structural deformation by finely adapting their conformation and arrangement. As a result, the material exhibits a remarkable dual-stimuli-responsive luminescence shift across almost the entire visible region: The emission color of the crystal gradually changes from cyan to green upon heating and then to red upon pressure compression. Furthermore, each stage exhibits a linear dependence of both the emission maximum and intensity on the stimulus and is fully reversible., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The simplest aminosulfinyl radical H 2 NSO has been generated in the gas phase through flash vacuum pyrolysis of CF 3 S(O)NH 2 at approximately 1000 K. Upon UV light irradiation (365 nm), 1,3-H migration occurs in H 2 NSO and furnishes an elusive N-amidyl radical HNSOH in syn and anti conformations in cryogenic matrices (N 2 or Ar, 15 K). Further 266 nm laser irradiation results in dissociation of HNSOH to H 2 O and SN and concomitant reformation of H 2 NSO in trace amount. The identification of H 2 NSO, syn-HNSOH, and anti-HNSOH by matrix-isolation IR spectroscopy is supported by high-level quantum chemical computations., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Chemical reactions involving quantum mechanical tunneling (QMT) increasingly attract the attention of scientists. In contrast to the hydrogen-tunneling as frequently observed in chemistry and biology, tunneling solely by heavy atoms is rare. Herein, we report heavy-atom tunneling in trifluoroacetyl nitrene, CF 3 C(O)N. The carbonyl nitrene CF 3 C(O)N in the triplet ground state was generated in cryogenic matrices by laser (193 or 266 nm) photolysis of CF 3 C(O)N 3 and characterized by IR and EPR spectroscopy. In contrast to the theoretically predicted activation barriers (>10 kcal mol -1 ), CF 3 C(O)N undergoes rapid rearrangement into CF 3 NCO with half-life times of less than 10 min and unprecedentedly large 14 N/ 15 N kinetic isotope effects (1.18-1.33) in solid Ar, Ne, and N 2 matrices even at 2.8 K. The tunneling disappearance of CF 3 C(O)N becomes much slower in the chemically active toluene and in 2-methyltetrahydrofuran at 5 K., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Neutral five-atomic cumulenes formally consisting of two pseudohalogens (e.g., NCO, NNN, NSO) by sharing the central nitrogen atom are exotic species that have been barely studied. Through flash vacuum pyrolysis of CF 3 S(O)NCO at ca. 1200 K, sulfinyl isocyanate, bearing resonance structures of O=C-N=S=O and O=C=N-S=O, has been generated in the gas phase and subsequently characterized in cryogenic matrices (Ar and N 2 ). Its reversible conformational (syn and anti) interconversion and photodecomposition were observed., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We herein report a rigid nested metal-organic framework (MOF) featuring a unique thermoresponsive gating adsorption behavior, which, in contrast to any known flexibility modes for stimuli-responsive MOFs, depends on the thermal motion of the extra-framework counterions. In addition, this MOF also exhibits adsorption selectivity of CO 2 over N 2 , H 2 , and Ar at 273 K, thus enabling a strategic separation and encapsulation of CO 2 ., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Metal-organic frameworks (MOFs) are shown to be good examples of a new class of crystalline porous materials for guest encapsulation. Since the encapsulation/release of guest molecules in MOF hosts is a reversible process in nature, how to prevent the leaching of guests from the open pores with minimal and nondestructive modifications of the structure is a critical issue. To address this issue, we herein propose a novel strategy of encapsulating guests by introducing size-matching organic ligands as bolts to lock the pores of the MOFs through deliberately anchoring onto the open metal sites in the pores. Our proposed strategy provides a mechanical way to prevent the leaching of guests and thereby has less dependence on the specific chemical environment of the hosts, thus making it applicable for a wide variety of existing MOFs once the size-matching ligands are employed., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)