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CCS Chemistry 2023年第10期5卷 2277-2289页

作者： Xiaolin Li Wei Hao Niannian Yi Yan-Mei He Qing-Hua Fan Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

Asymmetric hydrogenation of all-carbon aromatics is still a long-standing challenge in the area of asymmetric catalysis.To date,asymmetric(transfer)hydrogenation of naphthols and phenols remains unexplored.Here,we describe a new strategy for such asymmetric transformation via a bimetallic cooperative heterogeneous and homogeneous catalysis.By using HCOONa as the hydrogen source,various naphthols and phenols were partially hydrogenated in HFIP catalyzed by commercial Pd/C catalyst to give ketone intermediates.Further adding the second chiral Ru-tethered-TsDPEN catalyst and MeOH realized the asymmetric reduction of the resulting ketones in a one-pot manner,furnishing chiral alcohols with good to excellent enantioselectivity(up to 99%ee).The use of HFIP is crucial for suppressing ketone over-reduction via heterogeneous catalysis.More importantly,tandem asymmetric transfer hydrogenation of naphthols was also achieved by tuning the volume ratio of mixed HFIP/MeOH solvent,affording chiral 1,2,3,4-tetrahyronaphthols with excellent enantioselectivity but relatively low yield and limited substrate scope.

关键词： enantioselective hydrogenation arenols bimetallic catalysis heterogeneous catalysis homogeneous catalysis

Recent Applications of homogeneous catalysis in Electrochemical Organic Synthesis

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CCS Chemistry 2022年第4期4卷 1120-1152页

作者： Xu Cheng Aiwen Lei Tian-Sheng Mei Hai-Chao Xu Kun Xu Chengchu Zeng School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210023 College of Chemistry and Molecular Sciences Institute for Advanced Studies(IAS)Wuhan UniversityWuhan 430072 State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032 State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005 Faculty of Environment and Life Beijing University of TechnologyBeijing 100124

Although the combination of electrochemistry and homogeneous catalysis has proven to be a powerful strategy for achieving a diverse array of novel transformations,some challenges such as controlling the diffusion of catalyst-related species and the instability of catalysts at electrodes remain to be overcome.Herein,we review recent advances in electrochemical homogeneous catalysis,focusing on electrochemical noble-transition-metal catalysis,photoelectrochemical catalysis,and electrochemical enantioselective catalysis.The topics discussed include:(1)how the noblemetal catalystworks in the presence of cathodic hydrogen evolution,(2)how the photocatalyst gets enhanced redox property,and(3)how the enantioselectivity is regulated in a catalytic electrochemical reaction.

关键词： electrochemistry homogeneous catalysis transition-metal catalysis electrophotocatalysis enantioselective catalysis

Combinations of electron and proton donors in transition-metal complex mediated nitrogen reduction reactions

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Science China Chemistry 2024年第7期67卷 2136-2154页

作者： Delong Han Li Yang Hao Huang Priyanka Chakraborty Shashikant U.Dighe Kuo-Wei Huang KAUST catalysis Center and Division of Physical Science and Engineering King Abdullah University of Science and TechnologyThuwal 23955Saudi Arabia Agency for Science Technologyand ResearchInstitute of Materials Research and Engineering and Institute of Sustainability for ChemicalsEnergy and EnvironmentSingapore 138634Singapore

Nitrogen fixation is a complex process involving the transfer of six electrons and protons.Diverging from the conventional Haber-Bosch process,which relies on hydrogen(H_(2))to provide both electrons and protons to reduce nitrogen(N_(2)),homogeneous transition metal complex-catalyzed N_(2)reduction reactions(NRR)employ an array of electron and proton donors or even electron donors combined with silanes.As the synthesis of diverse catalytic progress,the categories of donors have seen rapid expansion.However,existing literature only provides summaries regarding the metal,ligands,and mechanism.Despite the significance of electron and proton donor combinations in nitrogen reduction reactions,no literature has thoroughly reviewed this aspect.Therefore,we hereby compiled a comprehensive list of commonly used reagents in N_(2)reduction and classified them according to their specific donor combinations.This review presents clear and organized information about these combinations,along with a summary of their general performance trend in NRR with related catalysts.Finally,we conclude the discussion by highlighting key points for researchers to consider when selecting catalysts and donor combinations,with the ultimate goal of advancing the field of nitrogen fixation.

关键词： dinitrogen reduction reaction reducing donor combination transition metal complexes homogeneous catalysis

Recent Advances in Catalytic Carbonylation Reactions in Alternative Reaction Media

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Chinese Journal of Chemistry 2024年第4期42卷 406-429页

作者： Csaba Árvai László T.Mika Department of Chemical and Environmental Process Engineering Faculty of Chemical Technology and BiotechnologyBudapest University of Technology and EconomicsMűegyetem rkp.3H-1111 BudapestHungary

Since the discovery of the hydroformylation(oxo-synthesis or Roelen reaction)and the Reppe-reaction,the transition metal-catalyzed carbonylation reactions,providing versatile,facile,and even atom-economic methods for the selective incorporation of C=O functionality to various skeletons,have gained tremendous importance in synthetic organic chemistry from laboratories to industrial applications.The carbonylation of carbon-carbon multiple bonds,aromatic halides,triflates,etc.,in the presence of various nucleophiles has led the way to produce aldehydes,carboxylic acids,esters,amides,etc.,in the fine chemical industry.However,these protocols usually proceed in conventional,fossil-based,and usually toxic reaction environments.Thus,several attempts have been directed to developing efficient carbonylation methods in alternative,less harmful,non-fossil-based and even in renewable reaction media.In this review,we overview the recent applications of alternative solvents such as water,biomass-based alcohols,γ-valerolactone(GVL),2-methyltetrahydrofuran(2-MeTHF),ionic liquids(ILs),deep eutectic solvents(DES),alkyl levulinates,limonene,α-pinene,and dimethyl carbonate as well as fluorous media to improve efficiency,safety and environmentally benign nature of carbonylation protocols.

关键词： Carbonylation catalysis Solvents Green chemistry Carbon monoxide Transition metals homogeneous catalysis Palladium

Palladium Complexes with N,O-Bidentate Ligands Based on N-Oxide Units from Cyclic Secondary Amines:Synthesis and Catalytic Application in Mizoroki-Heck Reaction

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Chinese Journal of Chemistry 2024年第3期42卷 294-300页

作者： Xuefeng Jia Yanyan Wen Changhui He Xianqiang Huang Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education School of Chemistry and Materials ScienceShanxi Normal UniversityTaiyuanShanxi030032 China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry & Chemical EngineeringLiaocheng UniversityLiaochengShandong252059 China

Palladium-catalyzed Mizoroki-Heck reaction is a powerful and efficient method for construction of Csp2–Csp2 bonds.Herein,four palladium complexes(I—IV)with N,O-bidentate ligands(L1—L4)based on N-oxide units from cyclic secondary amines were easily synthesized and successfully applied in Mizoroki-Heck reaction of aryl bromides with electron-deficient olefins.X-ray diffraction analyses indicated the palladium(II)atom of II took the distorted square planar geometry and was four-coordinated by nitrogen and oxygen atoms from two ligands(L2).Two free chloride ions were presented as counter anions in complex II.But the palladium(II)center of IV was coordinated by nitrogen and oxygen atoms from one ligand(L4)as well as two chlorine atoms,which exhibited the nearly square-planar geometry.The study on catalytic properties of palladium complexes revealed that complex II exhibited high activity superior to the other complexes.The coupling reactions of a series of aryl bromides and olefin derivatives proceeded in the presence of 2—5 mol%palladium complex II,giving the desired products in good to excellent yields.The advantages of this method such as good compatibility of functional groups,high yields,and short reaction times made it more attractive for constructing Csp2–Csp2 bonds in the synthesis of functional molecules and materials.

关键词： Palladium complexes N,O-Bidentate ligands N-Oxide units Mizoroki-Heck reaction Aryl bromide Electron-deficient olefins C—C coupling homogeneous catalysis Substituent effects

Dangling Ligand Enables an Iron Hexa-Coordinated Molecular Catalyst for Water Oxidation by Photocatalysis

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CCS Chemistry 2024年第3期6卷 623-630页

作者： Bing Yang Qi Liu Xiang-Zhu Wei Tao Lei Qing-Qing Yang Xu-Zhe Wang Jing-Xin Jian Xin Jiang Chen-Ho Tung Li-Zhu Wu Key Laboratory of Photochemical Conversion and Optoelectronic Materials New Cornerstone Science LaboratoryTechnical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190 School of Future Technology University of Chinese Academy of SciencesBeijing 100049

Photocatalytic water oxidation reaction by transition metal complexes remains a challenge because of their poor stability under irradiation,especially for earth-abundant metal catalysts.In this regard,ironbased water oxidation catalysts are prone to hydrolysis and/or dissociate the ligands to form nanoparticles under a real catalytic condition.Herein,we describe a unique hexa-coordinated catalyst 1[Fe^(II)(Py_(3)tacn)Cl_(2)]and its reference 2[Fe^(II)(PhPy_(2)tacn)Cl_(2)]with a dangling pyridyl ligand and a phenyl group,respectively.We anticipated that the dynamically open and close coordination behaviors of the pyridyl ligand enabled balance of the reactivity and stability of catalyst 1.To our delight,the“open form”of catalyst 1 provided a free coordination site,and the“close form”guaranteed its molecular integrity,resulting in a water oxidation reaction with high efficiency and robustness.The turnover number and turnover frequency values of 2332 and 60 s^(−1)are the highest known to date among iron-based homogeneous water oxidation systems under visible light irradiation.

关键词： water oxidation photocatalysis homogeneous catalysis iron complexes dangling ligand intermediates characterization

Photodegradable polar-functionalized polyethylenes

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National Science Review 2023年第7期10卷 124-133页

作者： Chaoqun Wang Jian Xia Yuxing Zhang Xiaoqiang Hu Zhongbao Jian State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences School of Applied Chemistry and Engineering University of Science and Technology of China

The degradation of plastics has attracted much attention from the global community.Polyethylenes(PEs),as the most abundant synthetic plastics,are most frequently studied.PE is non-degradable and non-polar because of the sole presence of the pure hydrocarbon components.Concurrent incorporation of both in-chain cleavable and functional groups into the PE chain is an effective pathway to overcome the non-degradable and non-polar issue;however,the method for achieving this pathway remains elusive.Here,we report a strictly non-alternating(>99%) terpolymerization of ethylene with CO and fundamental polar monomers via a coordination-insertion mechanism using late transition metal catalysts,which effectively prevents the formation of undesired chelates originating from both co-monomers under a low CO concentration.High-molecular-weight linear PEs with both in-chain isolated keto(>99%) and main-chain functional groups are prepared.The incorporation of key low-content isolated keto groups makes PEs photodegradable while retaining their desirable bulk material properties,and the introduction of polar functional groups considerably improves their surface properties.

关键词： degradable plastic homogeneous catalysis C1 chemistry non-alternating copolymerization polyolefin

New Mechanistic Insights on homogeneous catalysis ＆Bio-catalysis from Multi-Scale Simulations

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New Mechanistic Insights on Homogeneous Catalysis ＆Bio-Cata...

Catalytic Arylalkylation of Alkenyl Amines at Remote Sites via Directed Nickel catalysis

第十三届全国量子化学会议

作者：钟龙华 Department of Chemistry South University of Science and Technology of China

Computational chemistry has played an important role in elucidating mechanisms of metal-mediated organic and enzymatic reactions（including the origins of chemo-, regio-, and stereo-selectivities）. Some of our recent studies revealed new mechanistic insights on several metal-mediated organic and enzymatic reactions(e.g. Ru-catalyzed unusual trans-addition hydrofunctionalization（Wu-Trost mechanism）, Ni-catalyzed selective C-O activation, heme dioxygenases（TDO） and Ni-dependent lactate racemase（LarA）.1-2 These examples not only explain the experimental observations, but also some of our predictions were subsequently verified experimentally.

关键词： homogeneous catalysis bio-catalysis reaction mechanism multi-scale simulations

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Chinese Journal of Chemistry 2023年第6期41卷 631-636页

作者： Jian Han Yinheng Tang Jie Huang Chun Luo Lanlan Zhang Wenyi Li Chao Wang College of Chemistry and Materials Science Hengyang Normal UniversityKey Laboratory of Functional Metal-Organic Compounds of Hunan ProvinceKey Laboratory of Functional Organometallic Materials of Hunan Province UniversitiesHengyangHunan 421008China Tianjn Key Laboratory of Structure and Performance for Functional Molecules College of ChemistryTianjin Normal UniversityTianjin 300387China Jiangsu Key Laboratory of Advanced Organic Materials Schoolof Chemistryand Chemical EngineeringNanjing University NanjingJiangsu 210023China

Directing group-assisted, transition metal-catalyzed three-component difunctionalization of alkenes has emerged as a powerful tool to drive molecular complexity. However, this strategy generally works with the substrates bearing directing groups in close proximity to the alkene moieties, due to the preference for formation of kinetically stable five-membered metallacycles. Herein, we have disclosed a complementary strategy to accomplish a nickel-catalyzed remote arylalkylation of alkenyl amines with excellent regioselectivity and diastereofidelity, involving rare six- or seven-membered metallacycles. This general protocol is compatible with a series of δ- and ε-alkenyl amines, providing corresponding valuable δ,ε- and ε,ζ-difunctionalized aliphatic amines that would be difficult to synthesize. The coordination of the bidentate picolinamide auxiliary and the facile oxidative addition of alkyl halides to Ni(I) species are the key to the success of the developed remote olefin dicarbofunctionalization.

关键词： Nickel homogeneous catalysis Arylalkylation Amines Picolinamide Synthetic methodology Boron

Manganese-Catalyzed Anti-Markovnikov Hydroarylation of Enamides:Modular Synthesis of Arylethylamines

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Chinese Journal of Chemistry 2022年第13期40卷 1546-1552页

作者： Yjie He Chaoyu Du Jian Han Jie Han Chengjian Zhu Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu 210023China Green catalysis Center College of Chemistry and Molecular EngineeringZhengzhou UniversityZhengzhouHenan 45000iChina Advanced Catalytic Engineering Research Center of the Ministry of Education Hunan UniversityChangshaHunan 410082China

The arylethylamine framework is a prevalent motif in a great range of biologically important organic compounds.One intractable task for frontline drug discovery is to find structurally new medicine candidates instead of opioid,based on the construction of a rich chemical space of arylethylamine motif In this report,a practical protocol for the synthesis of arylethylamine functionality common in pharmaceutical chemicals has been developed.It proceeds by Mn-catalyzed anti-Markovnikov hydroarylation of electron-rich enamides under mild conditions without the use of ligands.In spite of mismatched electronic effects during the manganese-mediated migratory insertion process,both terminal and internal enamides can be regioselectively hydroarylated with various aryl boronic acids in 15 min.Also,the successful hydroalkenylation of enamides with alkenyl boronic acids in air atmosphere affords an elegant route to synthetically useful β-alkenylated amines in satisfactory yields.The synthetic robustness and practicality of the reaction reveal its simple operation,short reaction time,viability on a gram-scale and its value in late-stage modification of complex molecules.

关键词： Alkenes Anti-Markovnikov homogeneous catalysis Amines Difunctionalization