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rhodium-catalyzed formal[4+3]annulation reaction of N-methoxybenzamides with gem–difluorocyclopropenes:A combination of experimental and theoretical studies

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Chinese Chemical Letters 2022年第6期33卷 2987-2992页

作者： Yimiao He Limei Tian Xuexue Chang Zeming Qu Yanmin Huang Chusheng Huang Qing Sun Honggen Wang Guangxi Key Laboratory of Natural Polymer Chemistry and Physics College of Chemistry and MaterialsNanning Normal UniversityNanning 530001China Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China School of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhou 510006China

A rhodium-catalyzed[4+3]cycloaddition reaction between N-methoxybenzamides and gem–difluorocyclopropenes is described.The reaction offers a mild and efficient approach towards the synthesis of fluorinated 2 H-azepin-2-ones with broad substrate scope.A consecutive HOAc-assisted C–N bond formation and fluorine elimination are involved as key steps for success as illustrated by detailed DFT studies.

关键词： gem-Difluorocyclopropene Fluorinated 2H-azepin-2-one C-H functionalization Oxidizing directing group rhodium [4+3]Annulation

rhodium-Catalyzed Direct C-H Alkenylation of Indoles with Alkenyl Borates

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Chinese Journal of Chemistry 2021年第10期39卷 2823-2828页

作者： Ze-Tian Wang Zi-Ang Zheng Peng-Jie Li Chun-Ni Zhou Shao-Jun Cai Biao Xiao Liang Wang Key Laboratory of Optoelectronic Chemical Materials and Devices Ministry of EducationSchool of Chemical and Environmental EngineeringJianghan University8 Sanjiaohu RoadWuhanHubei430056 China

Main observation and conclusion A new Rh(Ⅲ)-catalyzed direct C—H alkenylation of 2,3-unsubstitued indoles with alkenyl borates through C—H activation followed by transmetallation was described.This protocol provides an efficient method for the synthesis of terminal C2-alkenylindoles under mild conditions,and also shows broad substrate scope and high functional group tolerance with respect to both components.Furthermore,the C2-alkenylated indole can be easily transformed into carboline derivative,which is an important polycyclic indole moiety in natural products and drug molecules.

关键词： rhodium C-H activation Terminal alkenylindoles Alkenyl borates Nitrogen heterocycles

rhodium(Ⅱ)-Catalyzed [4+3] Cyclization of Triazoles with Indole Derivatives and Its Application in the Total Synthesis of (±)-Aurantioclavine

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Chinese Journal of Chemistry 2021年第5期39卷 1145-1152页

作者： Shengguo Duan Bing Xue Hui Meng Zihang Ye Ze-Feng Xu Chuan-Ying Li Department of Chemistry Zhejiang Sci-Tech UniversityHangzhouZhejiang 310018China

An efficient rhodium(Ⅱ)-catalyzed[4+3]cyclization reaction of 1-sulfonyl-1,2-3-triazoles and indoles was developed.Azepino[5,4,3-ccflindoles,which are widely distributed in ergot alkaloids with various biological activities,could be obtained in good to excellent yields.In addition,the total synthesis of(±)-aurantioclavine was completed in four steps from the known compound 1a adopting this[4+3]cyclization as a key step.

关键词： Triazoles rhodium Alkaloids Cyclization Aurantioclavine

rhodium(Ⅰ)-Catalyzed Enantioselective C(sp^(3))-H Functionalization via Carbene-Induced Asymmetric Intermolecular C-H Insertion

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Chinese Journal of Chemistry 2021年第7期39卷 1911-1915页

作者： Bo Liu Ming-Hua Xu Shenzhen Grubbs Institute and Department of Chemistry Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and Technology1088 Xueyuan BoulevardShenzhenGuangdong518055 China Shanghai Institute of Materia Medica Chinese Academy of Sciences555 Zuchongzhi RoadShanghai201203 China

Main observation and conclusion Transition-metal-catalyzed C-H insertion of metal-carbene represents an excellent and powerful approach for C-H functionalization.However,despite remarkable advances in metal-carbene chemistry,transition metal catalysts that are capable of enantioselective intermolecular carbene C-H insertion are mainly constrained to dirhodium(Ⅱ)and iridium(Ⅲ)-based complexes.

关键词： Asymmetric catalysis C-H functionalization carbene C-H insertion rhodium

rhodium(Ⅲ)-Catalyzed C-H Vinylation of Arenes:Access to Functionalized Styrenes

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Chinese Journal of Chemistry 2018年第12期36卷 1143-1146页

作者： Jun Zhou Xin Li Gang Liao Bing-Feng Shi Department of Chemistry Zhejiang UniversityHangzhouZhejiang 310027China School of Chemistry and Biological EngineeringChangsha University of Science &TechnologyChangshaHunan 410114China

An effective method has been developed for Rh(III)‐catalyzed direct vinylation of arenes to give functionalized styrenes, using vinyltriethoxysilane as a convenient and inexpensive vinyl source. A wide variety of substrates, including 1‐aryl‐2‐pyrrolidinones, anilines, benzamides and ketones, were compatible with this reaction. Moreover, this method can be applied to the two‐step synthesis of functionalized indoles. Mechanistic investigation reveals that the reaction probably proceeds through an oxidative Heck/desilylation pathway. An effective Rh(III)‐catalyzed direct vinylation of arenes has been developed for the synthesis of functionalized styrenes, using vinyltriethoxysilane as a convenient and inexpensive vinyl source. The reaction is compatible with a wide range of directing groups and various functional groups. [ABSTRACT FROM AUTHOR]

关键词： C—C coupling C—H activation elimination Heck reaction olefination rhodium

rhodium(Ⅲ)-catalyzed intermolecular cyclization of anilines with sulfoxonium ylides toward indoles

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Chinese Chemical Letters 2019年第7期30卷 1374-1378页

作者： Zhihao Shen Chao Pi Xiuling Cui Yangjie Wu Department of Chemistry Henan Key Laboratory of Chemical Biology and Organic Chemistry Key Laboratory of Applied Chemistry of Henan UniversitiesZhengzhou University

rhodium(Ⅲ)-catalyzed synthesis of indole derivatives has been realized via cascade reaction of C -H alkylation/nucleophilic cyclization starting from readily available N-phenylpyridin-2-amines and sulfoxonium ylides. Notably, this transformation could smoothly proceed with high yields, good regioselectivity, and feature broad group tolerance and under redox-neutral condition to avoid external oxidant. The titled products are potentially important building blocks in the organic synthesis through various chemical transformations.

关键词： rhodium Cyclization Aniline Sulfoxonium ylide Indole

rhodium-catalyzed oxidative homologation of N-pyrimidyl indolines with alkynes via dual C—H activation: Facile synthesis of benzo[g] indolines

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Chinese Chemical Letters 2018年第6期29卷 907-910页

作者： Lianhui Wang Dan Xiong Lianghua Jie Chudan Yu Xiuling Cui Engineering Research Center of Molecular Medicine Ministry of Education Key Laboratory of Fujian Molecular Medicine Key Laboratory of Xiamen Marine and Gene Drugs School of Biomedical Sciences Huaqiao University

We herein report a highly regioselective rhodium-catalyzed C6-and C7—H bond functionalization of indolines with alkynes by using 2-pyrimidine as a directing group. Moreover, NH-free benzo[g]indole unit could be obtai... 详细信息

关键词： rhodium Indoline Alkyne Benzo[g]indoline C—H activation

Synthesis of palladium-rhodium bimetallic nanoparticles for formic acid dehydrogenation

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Journal of Energy Chemistry 2021年第1期30卷 301-309,I0010页

作者： Ilaria Barlocco Sofia Capelli Elisa Zanella Xiaowei Chen Juan JDelgado Alberto Roldan Nikolaos Dimitratos Alberto Villa Dipartimento di Chimica Universitàdegli Studi di MilanoMilan I-20133Italy Departamento de Ciencia de los Materiales Ingeniería Metalúrgica y Química InorgánicaFacultad de CienciasUniversidad de CádizCampus Río San PedroPuerto Real(Cádiz)E-11510Spain School of Chemistry Cardiff UniversityMain BuildingPark PlaceCF103AT CardiffUnited Kingdom Dipartimento di Chimica Industriale e dei Materiali Alma Mater Studiorum Universitàdi BolognaViale Risorgimento 4I-40136 BolognaItaly

Herein,we report for the first time the synthesis of preformed bimetallic Pd-Rh nanoparticles with different Pd:Rh ratios(nominal molar ratio:80-20,60-40,40-60,20-80) and the corresponding Pd and Rh monometallic ones by sol immobilization using polyvinyl alcohol(PVA) as protecting agent and NaBH4 as reducing agent,using carbon nanofibers with high graphitization degree(HHT) as the desired support.The synthesized catalysts were characterized by means of Transmission Electron Microscopy(TEM) and inductively coupled plasma optical emission spectroscopy(ICP-OES).TEM shows that the average particle size of the Pd-Rh nanoparticles is the range of 3-4 nm,with the presence of few large agglomerated nanoparticles.For bimetallic catalysts,EDX-STEM analysis of individual nanoparticles demonstrated the presence of random-alloyed nanoparticles even in all cases Rh content is lower than the nominal one(calculated Pd:Rh molar ratio:90-10,69-31,49-51,40-60).The catalytic performance of the Pd-Rh catalysts was evaluated in the liquid phase dehydrogenation of formic acid to H2.It was found that Pd-Rh molar ratio strongly influences the catalytic performance.Pd-rich catalysts were more active than Rh-rich ones,with the highest activity observed for Pd90:Rh10(1792 h^(-1)),whereas Pd69:Rh31(921 h^(-1)) resulted the most stable during recycling tests.Finally,Pd90:Rh10 was chosen as a representative sample for the liquid-phase hydrogenation of muconic acid using formic acid as hydrogen donor,showing good yield to adipic acid.

关键词： Palladium rhodium Alloy Formic acid Hydrogen Muconic acid

Synthesis of 2-aminothiazoles via rhodium-catalyzed carbenoid insertion/annulation of sulfoxonium ylides with thioureas

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Chinese Chemical Letters 2021年第8期32卷 2555-2558页

作者： Yuncan Chen Shan Lv Ruizhi Lai Yingying Xu Xin Huang Jianglian Li Guanghui Lv Yong Wu Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China Department of Pharmacy Taihe HospitalHubei University of MedicineShiyan 442000China

Sulfoxonium ylides as carbene precursors couple smoothly with thioureas in the presence of 5 mol% of rhodium(Ⅱ) acetate dimmer via carbenoid insertion to afford the corresponding 2-aminothiazoles with high chemoselectivity,providing a facile and efficient approach to access a variety of 2-aminothiazole derivatives with good functional groups tolerance.

关键词： 2-Aminothiazoles Carbene rhodium Sulfoxonium ylides Annulation