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Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China chemistry 2025年

作者： Shuai Zhang Pei-Zhi Liu Yan-Bo Li Qi Zhang Jun-Zhao Xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang Qian Peng Liang Yin Key Laboratory of Fluorine and Nitrogen chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-organic chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy chemistry 2025年第1期100卷 760-769页

作者： Lin Peng Yu Bai Hang Li Meixiu Qu Zhenhua Wang Kening Sun Advanced research institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

Lithium-sulfur （Li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （LiPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes Li2S dissolution and nucleation ***,the Li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： Lithium sulfur batteries

Photoinduced radical sulfur dioxide insertion with asymmetric cyclization of alkenes: accessing β-chiral sulfones bearing S-stereocentric cyclic sulfinamides

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Science China chemistry 2025年第01期 257-263页

作者： Jiapian Huang Chenxin Wang Xu Wang Xiaoyu Zhou Wei Xiao Jie Wu School of Pharmaceutical and Chemical Engineering & institute for Advanced Studies Taizhou University State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of chemistry and Chemical Engineering Henan Normal University

The generation of various β-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is described. This method features a broad substrate scope and excellent stereospecificity. Computational studies reveal that the dispersion interaction between sulfinyl group and CH2SO2Ph group plays a crucial role in the stereoselectivity control.

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Photosynthetic reaction pathways of natural and artificial systems

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Science China chemistry 2025年

作者： Shixing Lei Liting Bi Lingxuan Chen Zhanting Li Jia Tian State Key Laboratory of Organometallic chemistry and Shanghai Hong Kong Joint Laboratory in Chemical Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences

Photosynthesis converts solar energy into chemical energy through highly coordinated photosynthetic *** by natural systems,artificial photosynthesis aims to develop an efficient,sustainable,and cost-effective pathway for solar-tochemical *** review examines natural photosynthetic pathways,including retinal/rhodopsin-,bacteriochlorophyll-,and chlorophyll-based systems,highlighting their key components and ***,we outline reaction pathways in artificial photosynthetic systems constructed via heterogeneous,homogeneous,self-assembly,and semi-artificial strategies,focusing on water splitting,carbon fixation,and nitrogen ***,we offer insights into future directions for artificial photosynthesis,emphasizing the importance of using self-assembly strategies and the potential of using primitive phototrophic microorganisms as models.

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Enantioselective β-alkenylation of α,β-unsaturated aldehydes via chiral biphosphine ligand modified dirhodium(II) catalysis

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Science China chemistry 2025年

作者： Guangli Xu Hongda Chen Xiaoming Wang State Key Laboratory of Organometallic chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences School of chemistry and Materials Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences School of chemistry and Chemical Engineering Henan Normal University

Dirhodium(II) complexes have achieved great success in organic synthesis,and fine-tuning their catalytic properties with various bridging ligands is well-investigated in carbene ***,combining dirhodium(II) with a sophisticated ligand as a catalyst in other reactions is still extremely challenging,especially for the asymmetric synthesis of valuable chiral ***,we report a dirhodium(II)/(S)-MeO-BIPHEP catalytic system for the challenging asymmetric β-alkenylation of α,β-unsaturated aldehydes,affording the corresponding chiral conjugate addition products in good yields with high enantioselectivities.A couple of drug-derived substrates were also compatible with the protocol,which has been successfully used to prepare biologically relevant pyranochromene *** mechanistic studies suggested that the dirhodium core might remain intact over the catalytic cycle,and the chiral diphosphine ligand plays a key role in this novel reactivity and determining the high enantioselectivities of the asymmetric conjugate addition.

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High-performance poly(aromatic pyridine) copolymers with crown ether moieties for high temperature polymer electrolyte membrane fuel cells

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Science China chemistry 2025年

作者： Qian Wang Songhao Zhao Yunpeng Guo Wei Wei Lele Wang Jingshuai Yang Department of chemistry College of Sciences Northeastern University institute of Metal research Chinese Academy of Sciences

This study concentrates on the development of high temperature polymer electrolyte membranes（HT-PEMs）, which are essential components for HT-PEM fuel cells（HT-PEMFCs）. Although the phosphoric acid（PA）-doped polybenzimidazole（PBI） has been regarded as the successful HT-PEM, this system still suffers from several challenges, including the use of carcinogenic monomers, complex synthesis procedures, and poor solubility in organic solvents. To develop more cost-effective, readily synthesized and high-performance alternatives, this study employs a simply superacid-catalyzed Friedel-Crafts reaction to synthesize a series of poly（triphenyl-co-dibenzo-18-crown-6 pyridine） copolymers, denoted as P(TPx%-co-CEy%), using ptriphenyl, dibenzo-18-crown-6 and 4-acetylpyridine as monomers. The copolymerized hydrophilic and bulky crown ether unites introduce large free volumes and multiple interaction sites with PA molecules, as elucidated by theoretical *** microphase separation structures are formed as confirmed by atomic force microscope（AFM）, transmission electron microscopy（TEM） and small-angle X-ray scattering（SAXS）. Thus P(TPx%-co-CEy%) membranes exhibit excellent PA absorption and proton conduction abilities. For example, after immersing in 85 wt% PA at 30 °C, the P(TP91%-co-CE9%) membrane achieves a PA doping content of 205% and a high conductivity of 0.138 S cm-1at 180 °C, while maintaining a tensile strength of 7.5 MPa at room temperature. Without humidification and backpressure, the peak power density of an H2-O2cell equipped with P(TP91%-co-CE9%)/205%PA reaches nearly 1200 mW cm-2, representing one of the highest performances reported for PA-doped HT-PEMs to date. This work demonstrates the enormous potential of poly（triphenyl-co-crown ether pyridine） membranes in the HT-PEMFC applications.

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Stable copper boron–imidazolate cage as Cu-riched enzyme for highly efficient electrocatalytic CO2 reduction to ethylene

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Science China chemistry 2025年

作者： Jun-Qiang Chen Qiao-Hong Li Qin-Long Hong Ping Shao Hai-Xia Zhang Jian Zhang State Key Laboratory of Structural chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Single-atom catalyst has garnered widespread attention to mimic mature enzymes due to its well-defined atomic structure and coordination environments. However, since the carbon–carbon（C–C） coupling reactions require synergistic catalysis of multiple sites, single-atom catalysts suffer from insufficient active sites and unclear reaction mechanisms. Controlling the reaction intermediates in a precisely targeted pocket through careful metal–organic cage design is therefore crucial. Here, we prepare a tetrahedral [Cu6L4]-type boron–imidazolate cage integrating highly active Cu sites and optimized cavity, which exhibits enzyme like specific catalytic performance in electrochemical CO2reduction reaction（CO2RR） to enhance the selectivity of *** analyses and computational calculations suggest that the single Cu site together with neighboring boron–imidazolate ligands provides suitably synergistic effects that enable the energetically favorable formation of an *COCHO intermediate, a key step determining selectivity. As a result, the [Cu6L4]-type cage of BIC-145 achieves a Faradaic efficiency of 28% for C2H4maintaining an average current density of -3.54 mA cm-2over a 5-hour electrolysis period. This work represents the first example for studying single-metal site catalysts with ultra-low coordination numbers through the rational design of metal–organic cages.

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Record-breaking bifunctional oxygen electrocatalyst accomplished by a data-driven approach for zinc-air batteries

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Journal of Energy chemistry 2025年第1期100卷 144-145页

作者： Deviprasath Chinnadurai Zhi Wei Seh institute of Materials research and Engineering (IMRE) Agency for Science Technology and Research (A*STAR)

Rechargeable zinc-air batteries(ZABs) have recently drawn great attention in energy research due to their high theoretical capacity,low costs, and inherently safe nature [1–3]. However, the sluggish cathode reactions necessitate the development of bifunctional oxygen electrocatalysts with lower ΔE indicator values. The ΔE indicator is commonly employed to quantitatively evaluate the electrocatalytic activity of a bifunctional oxygen electrocatalyst,representing the overall overpotential from oxygen reduction reaction(ORR) to oxygen evolution reaction(OER).

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Enhancing anion conductivity in a highly alkali-stable eta topologic Cu(Ⅰ) framework via strong electrostatic repulsion

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Science China chemistry 2025年

作者： Xiaolu Wang Shaohui Guo Chao Suo Fuqiang Zhang Junhao Wang Wenjing Wang Daqiang Yuan Linfeng Liang Xianming Zhang College of chemistry Taiyuan University of Technology institute of Crystalline Materials Shanxi University School of chemistry and Materials Science Shanxi Normal University State Key Laboratory of Structural chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Metal-organic frameworks （MOFs） based on anion exchange membranes （AEMs） have garnered considerable interest,particularly for their potential to enhance ion conductivity by pre-introducing anions into *** approach is recognized as straightforward and effective for improving ion ***,developing high-performance AEMs is limited by the inherent instability and low resistance of *** study presents a novel 1,3,5-triazineμ3-bridged neutral Cu（I） framework,designated SXU-120 （where SXU represents Shanxi University）.This framework is synthesized using melamine,a widely available industrial product,as the starting material,achieving a high space-time yield exceeding 1.1 kg *** organic ligands and metal ions in SXU-120 are 3-connected,forming a rare eta topology with the point symbol 8～***-120 exhibits exceptional stability,even in a 10 M KOH solution,due to its high density of uncoordinated–NH2and carbonyl ***,the framework’s unique one-dimensional channels,characterized by their electronegativity,interact electrostatically with OH-ions,thereby accelerating OH-ion transfer along these ***,the OH-conductivity of this material reaches an impressive 0.49 S cm-1at 90°C under full humidity for 100 h,representing the highest OH-conductivity reported for MOF-based conductors to *** properties make SXU-120 a promising candidate for efficient AEM materials in next-generation industrial applications.

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