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Deciphering the role of ultra-low-loaded rhodium in NiFe-MIL-53 for superior oxygen evolution reaction

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Journal of Energy Chemistry 2025年第1期100卷 77-86页

作者： Jinzhi Jia Jinhua Zhang Kailu Guo Lanyue Zhang Gening Du Hao You Junfeng Huang Mudong Tu Hua Li Yong Peng Wei Dou Cailing Xu State key laboratory of Applied organic Chemistry College of Chemistry and Chemical EngineeringSchool of Materials and EnergyLanzhou UniversityLanzhou 730000GansuChina College of Chemistry and Chemical Engineering Luoyang Normal UniversityLuoyang 471934HenanChina

Designing highly active and stable electrocatalysts of oxygen evolution reaction(OER)is one of the crucial *** this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium(Rh@NiFe-MIL-53),is successfully prepared via the hydrothermal ***-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active *** importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe(OH)_(2)after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@***,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center(εd),accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining ***,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity(240 mV)with a small Tafel slope of 48.2 mV dec^(-1)and long-term durability(over1270 h at 10 m A cm^(-2)and 110 h at 200 mA cm^(-2)).This work presents a new perspective on designing highly efficient OER electrocatalysts.

关键词： NiFe-MIL-53 Rh Electrochemical reconstruction Catalytic mechanism Oxygen evolution reaction

Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

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Science China Chemistry 2025年第1期68卷 12-14页

作者： Wei-Lei Zhou Siwei Wang Yong Chen College of Chemistry and Materials Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional MoleculesInnovation Team of Optical Functional Molecular DevicesInner Mongolia Minzu UniversityTongliao 028000China College of Chemistry Nankai UniversityTianjin 300071China

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties^([1]).Particularly,two-dimensional(2D)materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry^([2,3]).

关键词： bonds purely dimensional

Enantioselective copper-catalyzed dearomative borylative cyclization of indoles and mechanistic insights

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Science China Chemistry 2025年第2期68卷 670-678页

作者： Yanfei Li Xuetao Li Zheng Zhang Yiliang Zhang Xiuping Yuan Jianjun Yin Simin Wang Wei Guan Qian Zhang Tao Xiong Jilin Province key laboratory of organic functional Molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun 130024China Institute of functional Material Chemistry Department of ChemistryNortheast Normal UniversityChangchun 130024China State key laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Chemical Engineering Harbin Normal UniversityHarbin 150025China

Alicyclic nitrogen heterocycles,such as enantioenriched polycyclic fused[1,2-a]indoline derivatives,are widespread in natural products,agrochemicals and pharmaceutical *** methods predominantly rely on the recent emerging Heck-type catalytic asymmetric dearomatization(CADA)protocol,wherein noble palladium catalysts commonly necessitate the form arylPd species-triggered these *** contrast,a more sustainable base metal catalysis paradigm through alkyl metal species disrupting the aromaticity,that is,the utilization of challenging asymmetric Csp3–Csp3 bond formation entry to such important chiral densely functionalized polycyclic molecular scaffolds,remains an elusive ***,we report the first copper-catalyzed dearomative borylative cyclization of indoles under mild reaction conditions,affording an array of valuable Bpin-containing pyrrolo-fused[1,2-a]indolines bearing four consecutive stereogenic centers with excellent enantioand *** synthetic potential was documented via an array of useful *** functional theory(DFT)calculation studies elucidated the origin of the chemo-,regio-,enantio-and diastereoselectivities of this conversion.

关键词： copper catalysis dearomatization borylative cyclization indoles DFT calculations

Cyano migration-mediated radical-polar crossover cyclopropanation

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Science China Chemistry 2025年第1期68卷 241-248页

作者： Ziqiang Wang Yasu Chen Jie Li Chen Zhu key laboratory of organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Frontiers Science Center for Transformative molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai 200240China

We report a novel cyano migration-mediated radical-polar crossover process,whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently *** transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic *** studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution,leading to the formation of the cyclopropane derivatives.

关键词： cyclopropanation cyano migration radical-polar crossover radical reactions

Enantioselective reductive conjugate alkenylation ofα,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De He Yun-Lei Luo Qiu-Quan Pan Qi-Wei Yao Xing-Zhong Shu State key laboratory of Applied organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis,yet their asymmetric variant remains ***,asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–*** manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl *** method facilitates the enantioselective addition of keto alkenyl groups toα,β-enones,resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access *** use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

Controlled cationic ring-opening polymerization of L-lactide by organic ion pair:novel approach to isotactic-rich and crystalline polylactide

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Science China Chemistry 2025年第1期68卷 394-402页

作者： Zhiqiang Ding Mingqian Wang Zijing Zhou Bin Wang Yuesheng Li Tianjin key laboratory of Composite&functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China

Living/controlled cationic ring-opening polymerization(ROP)of L-lactide is a promising approach to isotactic-rich and crystalline poly(L-lactide).In contrast with the unsubstituted lactones,L-LA can not be polymerized by organic Lewis acids or carbenium ions,and the state of the art in this field is the cationic ROP of L-LA catalyzed by BrФnsted acid/alcohol system via activated monomer ***,we reported the first example of controlled cationic ROP of L-LA by using Meerweintype ion pair[Me_(3)O]^(+)[B(C_(6)F_(5))_(4)]^(-)as the catalyst.[Me_(3)O]^(+)[B(C_(6)F_(5))_(4)]^(-)promoted rapid L-LA cationic polymerization in the absence of alcohol,producing isotactic-rich and crystalline PLLA without transesterification and epimerization side *** activated chain end mechanism,involving twice S_(N)2 substitution and configuration-inversion(S→R→S)with the assistance of released Me_(2)O,was proposed and further verified by density functional theory and control *** work expands the catalytic toolbox of isotactic-rich and crystalline polylactide *** represents a unique example of cationic-controlled polymerization of L-LA catalyzed by an organic ion pair.

关键词： organic ion pair controlled cationic ring-opening polymerization activated chain end mechanism isotactic-rich poly-lactide

Synergistic BrΦnsted/Lewis acid catalyzed atroposelective synthesis of aryl-β-naphthol

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Chinese Chemical Letters 2025年第1期36卷 293-298页

作者： Jiajun Lu Zhehui Liao Tongxiang Cao Shifa Zhu key laboratory of functional Molecular Engineering of Guang-dong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China School of Chemistry and Chemical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China State key laboratory of Elemento-organic Chemistry Nankai UniversityTianjin 300071China

Axially chiral binaphthol have achieved great success in asymmetric *** toα-binaphthol,axially chiral aryl-β-naphthol are far less ***,we report a method of asymmetric catalysis to constructβ-naphthol with up to 99%yield,95.5:4.5 enantiomeric ratio,using alkynyl esters as precursors and chiral phosphonic acid(CPA)/Lewis acid as *** steps involve oxygen transfer and de novo arene formation to set up the chiral ***,this methodology provides a versatile platform for structurally divergent synthesis of atroposelectiveβ-naphthol analogs,which are widely found in bioactive molecules and asymmetric catalysts.

关键词： Synergistic catalysis Atropisomerism Aryl-β-naphthol Enantioselectivity Tandem reaction

One-step synthesis of nanowoven ball-like NiS-WS_(2) for high-efficiency hydrogen evolution

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Chinese Chemical Letters 2025年第1期36卷 627-631页

作者： Lanfang Wang Jiangnan Lv Yujia Li Yanqing Hao Wenjiao Liu Hui Zhang Xiaohong Xu key laboratory of Magnetic molecules and Magnetic Information Materials of Ministry of Education School of Chemical and Material ScienceShanxi Normal UniversityTaiyuan 030032China

Exploring transition metal sulfide electrocatalysts with high-efficiency for hydrogen evolution reaction(HER)is essential to produce H_(2) fuel through water ***,novel nickel tungsten sulfide heterojunction(NiS-WS_(2))with a nanowoven ball-like structure were directed synthetized by a facile hydrothermal *** hierarchical Ni S-WS_(2) exhibited excellent HER activity with a relatively small overpotential of 142 and 137 m V at 10 m A/cm^(2) in 0.5 mol/L H_(2)SO_(4) and 1 mol/L KOH,which is much better than that of single NiS and WS_(2).The impressive performance of NiS-WS_(2) heterojunction is owed to the collective synergy of special morphological and more exposed active sites between the crystal interfacial of NiS and WS_(2).In addition,the hierarchical NiS-WS_(2) can facilitate the transport of charge/mass by optimized electronic structure,which further improves the HER activity of *** outcomes provide a simple method to prospect towards the design and application of heterostructures as efficient electrocatalysts,shedding some light on the development of functional materials in energy chemistry.

关键词： Nanowoven ball-like Hierarchical NiS-WS_(2) Hydrogen evolution reaction Synergy

Transition-metal-free isofunctional reaction of α,β-unsaturated ketones/nitriles

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Science China Chemistry 2025年第2期68卷 499-504页

作者： Runyou Ye Jialin Ming Qinyue Tao Tian-Yu Gao Jian-Heng Ye Da-Gang Yu Xiangge Zhou key laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China Inner Mongolia key laboratory of Fine organic Synthesis Inner Mongolia UniversityHohhot 010021China

Isofunctional reactions involving the cleavage of carbon-carbon double bonds(C=C)hold an important position in organic synthesis,as they allow for the restructuring of alkene carbon chains and enable the exchange of functional groups without introducing exogenous ***,these reactions are primarily divided into C=C/C=C metathesis and C=C/C=O metathesis,with most relying on the use of transition metal *** report herein a C=C/CH_(2) metathesis reaction that obviates the need for transition metals and directing groups,and is characterized by economic and straightforward *** reaction not only facilitates the replacement of nitriles with ketones,but also enables the replacement of ketones with nitriles,demonstrating great universality.

关键词： isofunctional reaction transition-metal-free C=C cleavage base-promoted Michael addition