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Modular Total Synthesis of (-)-Palmyrolide A and (+)-(5S,7S)-Palmyrolide A via Ring-Closing Metathesis and alkene Isomerization

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Chinese Journal of Chemistry 2021年第1期39卷 69-74页

作者： Yecai Lai Wei-Min Dai Laboratory of Advanced Catalysis and Synthesis Department of Chemistry and Hong Kong Branch of the Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina Baiyunshan Pharmaceutical General Factory Guang-zhou Baiyunshan Pharmaceutical Holdings Co.Ltd.Guangzhou 510515China

A pentamodule assembly approach has been established for total synthesis of the naturally occurring(-)-palmyrolide A and(+)-5,7-epi-palmyrolide *** using the racemic tert-butyl carbinol-containing alkyl iodide,the two diastereoisomeric macrolides could be obtained from the same sequence of reactions,demonstrating the flexibility of the multimodule assembly strategy for diverted total synthesis.

关键词： alkene B-Alky Suzuki-Miyaura cross-coupling Modular total synthesis Cross coupling Ring-closing metathesis

Convenient one-pot synthesis of functionalized cyclopentene via Sm/TMSCl/t-BuOH system mediated hydrodimerization cyclization of gem-diactivated alkene

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Chinese Journal of Chemistry 1999年第4期17卷 398-403,3页

作者：王磊张永敏 Department of Chemistry Zhejiang University at Xi-Xi Campus Hangzhou Zhejiang 310028 China

Functionalized cyclopentenes could be prepared through Sm/TMSCl/t-BuOH mediated hydrodimerization cyclization of gem-diactivated alkene in one-pot at room temperature. The trans- or trans, transform isomer is in the m... 详细信息

关键词： cyclopentene alkene Sm/TMSCl/t-BuOH system hydrodimerization cyclization

Controlling the Reactivity of IBA-N_(3)by Switching Halogen Salts:Providing a Universal Strategy for Haloazidation of alkenes

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Chinese Journal of Chemistry 2024年第16期42卷 1839-1845页

作者： Chen-Xi Xia Xin-Lei Sun Jinfeng Zhang Yue Ren Yan Yu Kuai Wang Ling-Guo Meng Key Laboratory of Green and Precise Synthetic Chemistry and Applications Ministry of Education/School of Chemistry and Materials ScienceHuaibeiNormal UniversityHuaibeiAnhui 235000China

Although various routes have been reported for haloazidation,unavoidable problems exist,such as environmentally unfriendly monomer halogen,the need for in situ generation of unstable halogen azides(XN3),applicability to one type of haloazidation and inability to precisely control ***,we developed a universal strategy for haloazidation of alkenes through controlling the reactivity of IBA-N_(3) by switching halogen salts,allowing for the synthesis of a diversity of halogen azide *** studies have shown that by tuning the reactivity of IBA-N_(3) via switching halogen salts,different intermediates can be controllably produced to achieve regioselectivityand chemoselectivity in thehaloazidationof alkenes.

关键词： Haloazidation alkene IBA-N_(3) Halogen salts Difunctionalization Selectivity Radicals Synthetic methods

Recent Advances in Cobalt-Catalyzed Regio-or Stereoselective Hydrofunctionalization of alkenes and Alkynes

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CCS Chemistry 2024年第5期6卷 1130-1156页

作者： Yan Li Xi Lu Yao Fu Hefei National Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026 Key Laboratory of Precision and Intelligent Chemistry Department of Applied ChemistrySchool of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026

Hydrofunctionalization of alkenes and alkynes is increasingly important in preparing and modifying carbon-centered organic molecules such as pharmaceuticals,agrochemicals,andmaterial *** development of transition-metal-catalysts has revolutionized the hydrofunctionalization of unsaturated hydrocarbons,greatly improving the synthetic efficiency and selectivity of these *** recent years,notable progress has been achieved in low-cost metal-catalyzed alkene and alkyne hydrofunctionalization reactions following the utilization of traditional precious metal catalysts,including palladium,platinum,and ***-abundant cobalt catalysts,which are low in toxicity and exhibit unique reactivity and selectivity,are widely implemented in academic and industrial *** this review,we highlight recent examples of cobalt-catalyzed hydrofunctionalization of alkenes and alkynes to provide an overview of hydrofunctionalization methods,particularly hydroalkylation *** reactions greatly expand the scope and utility of cobalt-catalyzed couplings of carbon—carbon *** also highlight the mechanistic considerations and selective determinants *** hope our discussion will be informative for future developments in cobalt catalysis and hydrofunctionalization reactions.

关键词： hydrofunctionalization cobalt-catalysis alkene alkyne regioselectivity stereoselectivity

Safe Hydroformylation of Aliphatic alkene in a Flow Reactor

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International Journal of Organic Chemistry 2018年第1期8卷 135-141页

作者： Hisashi Masui Eiki Honda Sakura Niitsu Mitsuru Shoji Takashi Takahashi Department of Pharmaceutical Sciences Yokohama University of Pharmacy Yokohama Japan

Despite hydroformylation being a very efficient method for the transformation of alkenes, it is not commonly employed in laboratories owing to the flammable/toxic nature of hydrogen and carbon monoxide gases and the necessity of high-pressure equipment in a batch system. Flow chemistry often raises the safety profiles against high-pressure and toxic gases because the diameter of the flow reactor is small. Herein, we show that aliphatic alkenes can be safely hydroformylated in a flow reactor. In our flow method, although the target hydroformylated product was obtained in a low yield (19%), toxic gases were safely treated using a flow reactor. Better yields could possibly be achieved by recycling of the unreacted alkene.

关键词： Hydroformylation Flow Synthesis alkene Carbon Monoxide Aldehyde

Chemoselective epoxidation of electron-deficient olefins with molecular oxygen via conjugated olefins epoxidation and BHT hydroxylation

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Science China Chemistry 2024年第9期67卷 3012-3018页

作者： Jia Nie Huanfeng Jiang Chuanle Zhu School of Chemistry and Chemical Engineering Key Lab of Functional Molecular Engineering of Guangdong ProvinceSouth China University of TechnologyGuangzhou 510640China Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing South China University of TechnologyGuangzhou 510640China

The chemoselective epoxidation of electron-deficient olefins in the presence of electron-rich alkene moieties is *** chemoselective epoxidation strategy undergoes a conjugated olefin epoxidation and BHT hydroxylation process to give various useful oxiranes in high yields,especially for the 2-substituted ***,this protocol features mild conditions,is transition-metal free,operationally simple,and gram-scalable,and tolerates diverse functional *** candidate HSD-16 is synthesized smoothly by this *** studies indicate molecular oxygen is the terminal oxidant and the O-source of the oxiranes.

关键词： chemoselective epoxidation alkene fluorine molecular oxygen

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Pd-catalyzed diastereoselective 1,1-diarylation of 1,1-disubstituted alkenes enabling the modular synthesis of 1,1,2,2-tetraarylethanes

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Science China Chemistry 2023年第12期66卷 3539-3545页

作者： Chengxi Zhang Yang Xi Jingping Qu Yifeng Chen Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science&TechnologyShanghai 200237China

The highly diastereoselective dicarbofunctionalization of substituted olefins still remains a daunting challenge in synthetic ***,we report a Pd-catalyzed diastereoselective 1,1-diarylation of 1,1-diarylethylene with chelation group free to enable the modular synthesis of smart material candidates,1,1,2,2-tetraarylethanes(TAEs),which represent the first protocol by assembling four different aryl groups into ethane *** mechanistic experiments suggest that the crucial Pd–H species generated in situ do not disengage from the alkene intermediate during the reaction.

关键词： 1,1,2,2-tetraarylethane palladium cross-coupling reaction alkene multicomponent reactions

Electrochemistry enabled selective vicinal fluorosulfenylation and fluorosulfoxidation of alkenes

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Chinese Chemical Letters 2022年第4期33卷 2009-2014页

作者： Yi Yu Yimin Jiang Shaofen Wu Zhaojiang Shi Jinnan Wu Yaofeng Yuan Keyin Ye Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou 350108china State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen 361005china

Both sulfur and fluorine play important roles in organic synthesis, the life science, and materials *** direct incorporation of these elements into organic scaffolds with precise control of the oxidation states of sulfur moieties is of great significance. Herein, we report the highly selective electrochemical vicinal fluorosulfenylation and fluorosulfoxidation reactions of alkenes, which were enabled by the unique ability of electrochemistry to dial in the potentials on demand. Preliminary mechanistic investigations revealed that the fluorosulfenylation reaction proceeded through a radical-polar crossover mechanism involving a key episulfonium ion intermediate. Subsequent electrochemical oxidation of fluorosulfides to fluorosulfoxides were readily achieved under a higher applied potential with the adventitious H;O in the reaction mixture.

关键词： alkene Chemoselectivity Electrochemistry Fluorine Sulfur

Enantioselective NiH-Catalyzed Reductive Hydrofunctionalization of alkenes

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Chinese Journal of Chemistry 2022年第5期40卷 651-661页

作者： Yuli He Jian Chen Xiaoli Jiang Shaolin Zhu State Key Laboratory of Coordination Chemistry Chemistry and Biomedicine Innovation Center(ChemBIC)Jiangsu Key Laboratory ofAdvanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210093 China

Enantioselective NiH-catalyzed reductive hydrofunctionalization of olefins has attracted much attention in recent *** simple chiral ligands,a wide array of functionalized olefins and electrophiles can undergo diverse transformations to afford hydrofunctionalized products,regio-and *** processes avoid the prior preparation of organometallic reagents,and can construct a stereogenic center at a carbon originating either from the olefin or from the *** review discusses the background,major progress and mechanistic investigations in this reaction.

关键词： Asymmetric catalysis Nicke catalysis Nickel hydride Hydrofunctionalization alkene