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Stereochemical editing:Catalytic racemization of secondary alcohols and amines

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Chinese Chemical Letters 2024年第5期35卷 17-31页

作者： Jun Zhang Zhiyao Zheng Can Zhu department of chemistry Fudan UniversityShanghai 200438China department of organic chemistry Arrhenius LaboratoryStockholm UniversityStockholm 10691Sweden

Chiral alcohols and amines are important structural units widely existing in pharmaceuticals,agrochemicals,and food *** kinetic resolution(DKR)is an efficient strategy to deliver optically active alcohols and amines from their *** the development of DKR method,racemization catalyst plays as a crucial element with the requirement of compatibility with the kinetic resolution(KR)*** this paper,recent advance in the catalytic racemization of secondary alcohols and amines is summarized based on different types of racemizing intermediates,which are redox racemization via ketone/imine intermediates,racemization via radical intermediates,and racemization via carbocation *** racemization of secondary alcohols and amines is also enclosed.

关键词： Racemization Secondary alcohols Amines Kinetic resolution Dynamic kinetic resolution

Cobalt(Ⅲ)hydride HAT mediated enantioselective intramolecular hydroamination access to chiral pyrrolidines

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Science China chemistry 2024年第6期67卷 2002-2008页

作者： Qi Meng Tao Qin Huanran Miao Ge Zhang Qian Zhang Jilin Province Key Laboratory of organic Functional Molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun130024China State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Enantioenriched pyrrolidines and derivatives are ubiquitous substructures in compounds of importance to medicinal and biological ***,we report an efficient cobalt-catalyzed intramolecular asymmetric hydroamination reaction that produces chiral pyrrolidines with good to excellent yield and *** with previously reported radicalinvolved methodologies for enantioenriched pyrrolidines,these conditions feature two elegant versatilities,enabling(1)the use of cobalt-catalyzed hydrogen atom transfer(HAT)to generate organocobalt intermediates that bring radical reaction to organometallic chemistry,and(2)enantioselective intramolecular C-N bond forging through an S_(N)2-like displacement involving dynamic kinetic resolution(DKR).This approach provides a new alternative and efficient methodology for enantioselective radical-involved C-N bond construction that can be used in the synthesis of both chiral pyrrolidines and homologous nitrogen heterocycles.

关键词： asymmetric catalysis radical hydroamination cobalt catalysis hydrogen atom transfer

Synthesis of uniform two-dimensional MoS_(2) films via thermal evaporation

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Nano Research 2024年第4期17卷 3217-3223页

作者： Xue-Wei Lu Zhewei Li Chen-Kai Yang Weijia Mou Liying Jiao Key Laboratory of organic Optoelectronics and Molecular Engineering of the Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China

Two-dimensional(2D)molybdenum disulfide(MoS_(2))holds great potential for various applications such as electronic devices,catalysis,lubrication,anti-corrosion and so *** evaporation is a versatile thin film deposition technique,however,the conventional thermal evaporation techniques face challenges in producing uniform thin films of MoS_(2) due to its high melting temperature of 1375℃.As a result,only thick and rough MoS_(2) films can be obtained using these *** address this issue,we have designed a vacuum thermal evaporation system specifically for large-scale preparation of MoS_(2) thin *** using K2MoS4 as the precursor,we achieved reliable deposition of uniform polycrystalline MoS_(2) thin films with a size of 50 mm×50 mm and controllable thickness ranging from 0.8 to 2.4 *** approach also allows for patterned deposition of MoS_(2) using shadow masks and sequential deposition of MoS_(2) and tungsten disulfide(WS_(2)),similar to conventional thermal evaporation ***,we have demonstrated the potential applications of the obtained MoS_(2) thin films in field effect transistors(FETs),memristors and electrocatalysts for hydrogen evolution reaction(HER).

关键词： thermal evaporation molybdenum disulfide two-dimensional memristors hydrogen evolution reaction

Electric-field-controlled highly regioselective thiocyanation of N-containing heterocycles

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Science China chemistry 2024年第4期67卷 1263-1269页

作者： Ming Gong Qian Wu Jung Keun Kim Mengmeng Huang Yabo Li Yangjie Wu Jong Seung Kim Henan Key Laboratory of Chemical Biology and organic chemistry Key Laboratory of Applied Chemistry of Henan UniversitiesCollege of ChemistryZhengzhou UniversityZhengzhou 450052China department of chemistry Korea UniversitySeoul 02841Korea

Achieving highly regioselective synthesis in organic chemistry is challenging due to the uncontrollable orientation between reacting *** electric fields(EEFs)can influence the reactivity and selectivity of the substrate by causing directional ***,scalable and efficient techniques for using EEFs as“smart catalysts”have been lacking,hindering their *** this study,we present a novel method for modifying the regioselectivity of quinoxaline-2(1H)-ones by functionalizing their C7-position using the electric double layer(EDL)*** approach led to moderate to good yields of the corresponding C7-thiocyanation *** calculations and control experiments demonstrated that EEFs could reverse the regioselectivity of quinoxaline-2(1H)-ones,allowing the C7-thiocyanation to proceed via a radical reaction ***,the resulting 7-thiocyano-1-methylquinoxaline-2(1H)-ones exhibited promising AIE *** work showcases a promising strategy for achieving highly regioselective functionalization by aligning the electric field with the desired reaction/bond axis.

关键词： electric fields reaction-axis rule electric double layer C7-thiocyanation C-S bond formation

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Recent advances in the synthesis and application of N-heterocyclic carbene-based molecular cages

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Science China chemistry 2024年第5期67卷 1510-1523页

作者： Qiongjie Chai Lixin Duan Yanzhe Ma Tianheng Hou Tao Tu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

N-Heterocyclic carbene(NHC)-based cages have emerged as a prominent and dynamic research area within the research field of chemistry. Leveraging the distinctive electronic and steric properties of NHC ligands, the design, synthesis, and application of these corresponding cages have garnered substantial scholarly interest. In recent years, we have witnessed the successful fabrication of diverse NHC-based cages through a range of synthetic methodologies, which hold significant potential for applications in molecular recognition and catalysis. In this review, we delve into the foundational synthetic strategies that underlie the creation of NHC-based cages, employing approaches encompassing metal–NHC chelation, coordination assembly,and covalent bonding. Additionally, we compile the diverse applications of these cages within catalytic processes and molecular recognition. Lastly, we shed light on the current limitations of synthesis and outline future trends in the development of NHCbased cages.

关键词： N-heterocyclic carbene molecular cages supramolecular chemistry synthetic strategies applications

Copper-catalyzed conjugate addition of allene-derived nucleophiles to alkenyl-substituted carboxamides

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Chinese Chemical Letters 2024年第3期35卷 239-242页

作者： Bin Fu Yue Zhao Xiuping Yuan Yanfei Li Jianjun Yin Simin Wang Tao Xiong Qian Zhang Jilin Province Key Laboratory of organic Functional Molecular Design&Synthesis 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 Environmental Engineering Changchun University of Science and TechnologyChangchun 130012China

Catalytic Michael addition reaction represents a fundamental importance in organic synthetic *** corresponding conversions toward intrinsically low reactive enamide remains an ongoing *** herein report a copper-catalyzed conjugate addition of allenes toβ-substituted alkenyl amides,one of the most challenging Michael *** present method utilizes readily available allenes as the latent carbon-based nucleophiles and simple,commonβ-substituted alkenyl amides as starting materials,unlike previous methods that usually preinstall an activating group to improve the reactivity of amide or uses highly reactive stoichiometric quantities of ***,this approach shows good functional group compatibility and can be implemented under mild reaction conditions with excellent level of chemo-and regioselectivities.

关键词： CuH catalysis Allenes Unsaturated amide Conjugate addition Regioselectivity

Radical Arbuzov Reaction

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CCS chemistry 2024年第5期6卷 1312-1323页

作者： Linxiang Chai Jian Wang Jimin Yang Junyue Yin Zhuyong Zhang Yulu Cheng Lin Zhu Xiao-Song Xue Chaozhong Li department of chemistry University of Science and Technology of ChinaHefeiAnhui 230026 Shanghai Institute of organic chemistry Chinese Academy of SciencesShanghai 200032

The Arbuzov reaction(also known as the Michaelis–Arbuzov reaction)is one of the most fundamental transformations in organic chemistry and has been extensively used for the synthesis of organophosphorus compounds for over a ***,the reaction generally requires an elevated temperature and is applicable mainly to primary alkyl halides with poor functional group *** report herein a radical alternative to the conventional nucleophilic substitution ***,new radical phosphonylation reagents,9-fluorenyl o-phenylene phosphite and benzhydryl o-phenylene phosphite,have been developed for this *** photoredox-catalyzed reaction of a wide range of alkyl bromides or iodides with 9-fluorenyl(or benzhydryl)o-phenylene phosphite followed by workup with methanol(or ethanol)provides the corresponding dimethyl(or diethyl)alkylphosphonates in satisfactory yields at room temperature under mild *** method is applicable to primary,secondary,and even tertiary alkyl iodides and bromides and exhibits an excellent functional group tolerance,thereby enabling the late-stage modification of complex molecules and rapid synthesis of phosphonate-containing natural products and drug molecules.A mechanism involving the formation and subsequentβ-scission of phosphoranyl radicals is proposed.

关键词： Arbuzov reaction radicals phosphonylation photoredox catalysis alkyl halides

Advanced organic electrode materials for aqueous rechargeable batteries

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Science China chemistry 2024年第1期67卷 137-164页

作者： Gaojing Yang Yaxun Zhu Qi Zhao Zhimeng Hao Yong Lu Qing Zhao Jun Chen Frontiers Science Center for New organic Matter Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)College of ChemistryNankai UniversityTianjin 300071China

organic electrode materials take advantages of potentially sustainable production and structural tunability compared with present commercial inorganic electrode ***,their applications in traditional rechargeable batteries with nonaqueous electrolytes suffer from the premature failure and safety *** comparison,aqueous rechargeable batteries based on organic electrode materials have received extensive attentions in recent years for low-cost and sustainable energy storage systems due to their inherent *** review aims to provide a comprehensive summary on the recent progress in advanced organic electrode materials for aqueous rechargeable *** start from the overview of working principles and general design strategies of organic electrode materials in aqueous rechargeable *** the research advances of organic electrode materials in various aqueous rechargeable batteries are highlighted in terms of charge carriers(monovalent ions,multivalent ions,and anions).We emphasized the characteristics of organic electrode materials in various charge ***,the critical challenges and future efforts of aqueous organic rechargeable batteries are *** organic electrode materials with better electronic conductivity and fast reaction kinetics are still needed to build advanced aqueous batteries for commercial applications.

关键词： organic electrode materials aqueous batteries organic batteries rechargeable batteries

Ni-catalyzed highly regio- and stereo-selective diborylative cyclization of 1,6-enynes with diboron reagent

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Science China chemistry 2024年第3期67卷 981-989页

作者： Qitao Guan Zhen Shen Yiqiang Tian Genping Huang Chun Zhang Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic ScienceDepartment of ChemistrySchool of SciencesTianjin UniversityTianjin 300072China State Key Laboratory of Elemento-organic chemistry Nankai UniversityTianjin 300071China

The Ni-catalyzed highly selective diborylative cyclization of 1,6-enynes with diboron reagent has been developed. When pinB-Bdan was used, multiple types of boron-containing functional groups could be installed into organic molecule with great chemoselectivity and regioselectivity though this reaction. Meanwhile, if B_2pai_2 was employed, the asymmetric diborylative cyclization could be well induced by using strategy of dynamic kinetic resolution. Importantly, the above reactions could afford desired product with 100% atomic economy, and could be compatible with different series of substituents. The studies of further transformation well illustrated that different type products could serve diverse synthetic strategy. Notably, the reaction mechanism was intensively studied by density functional theory(DFT) calculations, which could reveal the mechanism of regio- and enantio-selective control.

关键词： nickel-catalyzed organoboron cyclization regioselectivity enantioselectivity