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The development of porous materials with flexible‐robust characteristics shows some unique advantages to target high performance for gas separation, but remains a daunting challenge to achieve so far. Herein, we report a carboxyl‐based hydrogen‐bonded organic framework (ZJU‐HOF‐8a) with flexible‐robust porosity for efficient purification of natural gas. ZJU‐HOF‐8a features a four‐fold interpenetrated structure with dia topology, wherein abundant supramolecular entanglements are formed between the adjacent subnetworks through weak intermolecular hydrogen bonds. This structural configuration could not only stabilize the whole framework to establish the permanent porosity, but also enable the framework to show some flexibility due to its weak intermolecular interactions (so‐called flexible‐robust framework). The flexible‐robust porosity of ZJU‐HOF‐8a was exclusively confirmed by gas sorption isotherms and single‐crystal X‐ray diffraction studies, showing that the flexible pore pockets can be opened by C3H8 and n‐C4H10 molecules rather by C2H6 and CH4. This leads to notably higher C3H8 and n‐C4H10 uptakes with enhanced selectivities than C2H6 over CH4 under ambient conditions, affording one of the highest n‐C4H10/CH4 selectivities. The gas‐loaded single‐crystal structures coupled with theoretical simulations reveal that the loading of n‐C4H10 can induce an obvious framework expansion along with pore pocket opening to improve n‐C4H10 uptake and selectivity, while not for C2H6 adsorption. This work suggests an effective strategy of designing flexible‐robust HOFs for improving gas separation properties. [ABSTRACT FROM AUTHOR]

Organic molecules bearing chiral sulfur stereocenters exert a great impact on asymmetric catalysis and synthesis, chiral drugs, and chiral materials. Compared with acyclic ones, the catalytic asymmetric synthesis of thio‐heterocycles has largely lagged behind due to the lack of efficient synthetic strategies. Here we establish the first modular platform to access chiral thio‐oxazolidinones via Pd‐catalyzed asymmetric [3+2] annulations of vinylethylene carbonates with sulfinylanilines. This protocol is featured by readily available starting materials, and high enantio‐ and diastereoselectivity. In particular, an unusual effect of a non‐chiral supporting ligand on the diastereoselectivity was observed. Possible reaction mechanisms and stereocontrol models were proposed. [ABSTRACT FROM AUTHOR]

Developing porous materials for C3H6/C3H8 separation faces the challenge of merging excellent separation performance with high stability and easy scalability of synthesis. Herein, we report a robust Hofmann clathrate material (ZJU‐75a), featuring high‐density strong binding sites to achieve all the above requirements. ZJU‐75a adsorbs large amount of C3H6 with a record high storage density of 0.818 g mL−1, and concurrently shows high C3H6/C3H8 selectivity (54.2) at 296 K and 1 bar. Single‐crystal structure analysis unveil that the high‐density binding sites in ZJU‐75a not only provide much stronger interactions with C3H6 but also enable the dense packing of C3H6. Breakthrough experiments on gas mixtures afford both high separation factor of 14.7 and large C3H6 uptake (2.79 mmol g−1). This material is highly stable and can be easily produced at kilogram‐scale using a green synthesis method, making it as a benchmark material to address major challenges for industrial C3H6/C3H8 separation. [ABSTRACT FROM AUTHOR]

Ring‐opening transformations of donor‐acceptor (D‐A) cyclopropanes enable the rapid assembly of complex molecules. However, the enantioselective formation of chiral quaternary stereocenters using substrates bearing two different acceptors remains a challenge. Herein, we describe the first palladium‐catalyzed highly diastereo‐ and enantioselective (3+2) cycloaddition of vinyl cyclopropanes bearing two different electron‐withdrawing groups, a subset of D‐A cyclopropanes. The key to the success of this reaction is the remote stereoinduction through hydrogen bond from chiral ligands, which thereby addressed the aforementioned challenge. A variety of chiral five‐membered heterocycles were produced in good yields and with high stereoselectivity (up to 99 % yields, 99 : 1 er and >19 : 1 dr). In‐depth mechanistic investigations, including control experiments and theoretical calculations, revealed the origin of the stereoselectivity and the importance of H‐bonding in stereocontrol. [ABSTRACT FROM AUTHOR]

Developing porous materials to overcome the trade‐off between adsorption capacity and selectivity for C2H2/CO2 separation remains a challenge. Herein, we report a stable HKUST‐1‐like MOF (ZJU‐50a), featuring large cages decorated with high density of supramolecular binding sites to achieve both high C2H2 storage and selectivity. ZJU‐50a exhibits one of the highest C2H2 storage capacity (192 cm3 g−1) and concurrently high C2H2/CO2 selectivity (12) at 298 K and 1 bar. Single‐crystal X‐ray diffraction studies on gas‐loaded ZJU‐50a crystal unveil that the incorporated supramolecular binding sites can selectively take up C2H2 molecule but not CO2 to result in both high C2H2 storage and selectivity. Breakthrough experiments validated its separation performance for C2H2/CO2 mixtures, providing a high C2H2 recovery capacity of 84.2 L kg−1 with 99.5 % purity. This study suggests a novel strategy of engineering supramolecular binding sites into MOFs to overcome the trade‐off for this separation. [ABSTRACT FROM AUTHOR]

Porous materials for C2H2/CO2 separation mostly suffer from high regeneration energy, poor stability, or high cost that largely dampen their industrial implementation. A desired adsorbent should have an optimal balance between excellent separation performance, high stability, and low cost. We herein report a stable, low‐cost, and easily scaled‐up aluminum MOF (CAU‐10‐H) for highly efficient C2H2/CO2 separation. The suitable pore confinement in CAU‐10‐H can not only provide multipoint binding interactions with C2H2 but also enable the dense packing of C2H2 inside the pores. This material exhibits one of the highest C2H2 storage densities of 392 g L−1 and highly selective adsorption of C2H2 over CO2 at ambient conditions, achieved by a low C2H2 adsorption enthalpy (27 kJ mol−1). Breakthrough experiments confirm its exceptional separation performance for C2H2/CO2 mixtures, affording both large C2H2 uptake of 3.3 mmol g−1 and high separation factor of 3.4. CAU‐10‐H achieves the benchmark balance between separation performance, stability, and cost for C2H2/CO2 separation. [ABSTRACT FROM AUTHOR]

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Abstract: A room‐temperature, visible‐light‐driven N‐centered iminyl radical‐mediated and redox‐neutral C−C single bond cleavage/radical addition cascade reaction of oxime esters and unsaturated systems has been accomplished. The strategy tolerates a wide range of O‐acyl oximes and unsaturated systems, such as alkenes, silyl enol ethers, alkynes, and isonitrile, enabling highly selective formation of various chemical bonds. This method thus provides an efficient approach to various diversely substituted cyano‐containing alkenes, ketones, carbocycles, and heterocycles. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)