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Palladium-catalyzed multi components oxy-aminofluorination and aminofluorination of gem-difluoroalkenes

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Chinese Chemical Letters 2024年第2期35卷 420-425页

作者： Fen Wu Xin Li Junbiao Chang Dachang Bai state key laboratory of Antiviral Drugs NMPA Key Laboratory for Research and Evaluation of Innovative DrugKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringPingyuan LaboratoryHenan Normal UniversityXinxiang 453007China state key laboratory of organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Organofluorine compounds are widely used in the realm of drug discovery and material science.Herein,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes with N-fluorobenzenesulfonimide(NFSI),in which NFSI was used as the nitrogen source and oxidant.The reaction provides an efficient and straightforward synthesis route of a series ofα-trifluoromethyl benzylic amines.Notably,three/four components oxy-aminofluorination processes were realized to giveα-trifluoromethyl benzylic ether with a terminal amino group,which proceed through C(sp^(3))-O bond cleavage of easily available ether and simultaneous introduced a fluorine,an amino and an oxy substituent in one pot with excellent regioselectivity.The divergent reactivity not only included the incorporation of one ether molecular,but also much more challenged two ether insertion with excellent selectivity through succession C(sp^(3))-O bonds cleavage.This protocol allows for concise synthesis of high value amines with fluoroalkyl-substituents and selectively transformation of easily available ethers by high-valent palladium catalysis.

关键词： Palladium Multi components Aminofluorination Oxy-aminofluorination C(sp^(3))-O bond cleavage

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 chemistry.Herein,we report an efficient cobalt-catalyzed intramolecular asymmetric hydroamination reaction that produces chiral pyrrolidines with good to excellent yield and enantiocontrol.Compared 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

Catalytic conversion of mixed polyolefins under mild atmospheric pressure

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The Innovation 2024年第2期5卷 98-106页

作者： Binzhi Zhao Hui Tan Jie Yang Xiaohui Zhang Zidi Yu Hanli Sun Jialiang Wei Xinyi Zhao Yufeng Zhang Lili Chen Dali Yang Jin Deng Yao Fu Zheng Huang Ning Jiao state key laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Beijing National laboratory for Molecular sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China The Institute for Advanced Studies Wuhan UniversityWuhan 430072China Hefei National laboratory for Physical sciences at the Microscale CAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyiChEMUniversity of Science and Technology of ChinaHefei 230026China state key laboratory of organometallic chemistry Chinese Academy of SciencesShanghai 200032China

The chemical recycling of polyolefin presents a considerable challenge,especially as upcycling methods struggle with the reality that plastic wastes typically consist of mixtures of polyethylene(PE),polystyrene(PS),and polypropylene(PP).We report a catalytic aerobic oxidative approach for polyolefins upcycling with the corresponding carboxylic acids as the product.This method encompasses three key innovations.First,it operates under atmospheric pressure and mild conditions,using O_(2) or air as the oxidant.Second,it is compatible with high-density polyethylene,low-density polyethylene,PS,PP,and their blends.Third,it uses an economical and recoverable metal catalyst.It has been demonstrated that this approach can efficiently degrade mixed wastes of plastic bags,bottles,masks,and foam boxes.

关键词： mixed Catalytic oxidative

Selective control of secondary alcohols upgrading using Ir-catalyzed cross-coupling strategy

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Science China chemistry 2024年第3期67卷 914-921页

作者： Siqi Yang Zeye Lu Jiale Ji Qingshu Zheng Tao Tu Shanghai key laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China Frontiers Science Center for Transformative Molecules School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China state key laboratory of organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The selective coupling of alcohols is a fascinating yet challenging approach for upgrading alcohols. Herein, we accomplished the controlled production of β-disubstituted ketones or upgraded secondary alcohols via the Ir-catalyzed cross-coupling of secondary alcohols in excellent yields with broad substrate scopes. This selective control was achieved by using an in-situ generated monoNHC-Ir or a tris-NHC-Ir complex as the catalysts, respectively. Mechanistic studies revealed that the delicate balance between dehydrogenation and hydrogenation abilities of these bifunctional catalysts is crucial for achieving different selectivity. The tris-NHC-Ir complex effectively facilitated dehydrogenation of alcohols and hydrogenation of intermediates, leading to the desired upgraded secondary alcohols. Conversely, the high dehydrogenation ability of the mono-NHC-Ir complex promoted the conversion of formed secondary alcohols back to ketones.

关键词： cross-coupling hydrogen-borrowing NHC-Ir complexes selectivity control upgrading of alcohols

Modularized viromimetic polymer nanoparticle vaccines(VPNVaxs) to elicit durable and effective humoral immune responses

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National Science Review 2024年第3期11卷 200-214页

作者： Zichao Huang Xinyu Zhuang Liping Liu Jiayu Zhao Sheng Ma Xinghui Si Zhenyi Zhu Fan Wu Ningyi Jin Mingyao Tian Wantong Song Xuesi Chen key laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences School of Applied chemistry and Engineering University of Science and Technology of China Changchun Veterinary Research Institute Chinese Academy of Agricultural Sciences Jilin Biomedical Polymers Engineering laboratory state key laboratory of Polymer Physics and chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Virus-like particle(VLP) vaccines had shown great potential during the COVID-19 pandemic, and was thought to be the next generation of antiviral vaccine technology due to viromimetic structures. However,the time-consuming and complicated processes in establishing a current recombinant-protein–based VLP vaccine has limited its quick launch to the out-bursting pandemic. To simplify and optimize VLP vaccine design, we herein report a kind of viromimetic polymer nanoparticle vaccine(VPNVax), with subunit receptor-binding domain(RBD) proteins conjugated to the surface of polyethylene glycol-b-polylactic acid(PEG-b-PLA) nanoparticles for vaccination against SARS-CoV-2. The preparation of VPNVax based on synthetic polymer particle and chemical post-conjugation makes it possible to rapidly replace the antigens and construct matched vaccines at the emergence of different viruses. Using this modular preparation system, we identified that VPNVax with surface protein coverage of 20%–25% had the best immunostimulatory activity, which could keep high levels of specific antibody titers over 5 months and induce virus neutralizing activity when combined with an aluminum adjuvant. Moreover, the polymer nano-vectors could be armed with more immune-adjuvant functions by loading immunostimulant agents or chemical chirality design. This VPNVax platform provides a novel kind of rapidly producing and efficient vaccine against different variants of SARS-CoV-2 as well as other viral pandemics.

关键词： vaccine polymer nanomaterials SARS-CoV-2

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 chemistry.Whereas corresponding conversions toward intrinsically low reactive enamide remains an ongoing challenging.We herein report a copper-catalyzed conjugate addition of allenes toβ-substituted alkenyl amides,one of the most challenging Michael acceptors.The 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 organometallics.Hence,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

Efficient capture of difluorocarbene by pyridinium 1,4-zwitterionic thiolates:A concise synthesis of difluoromethylene-containing 1,4-thiazine derivatives

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Chinese Chemical Letters 2024年第4期35卷 367-370页

作者： Zhiwei Chen Heyun Sheng Xue Li Menghan Chen Xin Li Qiuling Song Institute of Next Generation Matter Transformation College of Materials Science&Engineering and College of Chemical Engineering at Huaqiao UniversityXiamen 361021China Fujian University key laboratory of Molecule Synthesis and Function Discovery College of ChemistryFuzhou UniversityFuzhou 350108China state key laboratory of organometallic chemistry and key laboratory of Organofluorine chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

A practical method for the construction of difluoromethylene-containing 1,4-thiazine moieties using readily available diethyl bromodifluoromethanephosphonate(BrCF_(2)PO(OEt)_(2))as difluorocarbene precusor has been developed.This transformation features the efficient capture of difluorocarbene by pyridinium 1,4-zwitterionic thiolates.A series of structurally novel and functionalized difluoromethylene-containing 1,4-thiazine derivatives were thus synthesized in good yields.

关键词： Difluoromethylene Pyridinium 1 4-zwitterionic thiolates 1 4-Thiazine derivatives

Polyethylene to gasoline via a self-supplied hydrogen strategy

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Science China chemistry 2024年

作者： Yong Tang state key laboratory of organometallic chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

Polyethylenes (PEs) are one of the most widely used plastics in almost every aspect of modern life and are produced on a huge scale (a market volume of 110.13 million metric tons worldwide in 2022)[1]. A large portion of the PEs are used once and discarded as waste, which caused severe problems such as plastic pollution as well as a waste of the fossoil resource.

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Palladium(Ⅱ)-Catalyzed Markovnikov Hydroalkynylation of Unactivated Terminal Alkenes

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Chinese Journal of chemistry 2024年第1期42卷 29-34页

作者： Chuanqi Hou Pinhong Chen Guosheng Liu Sstate key laboratory of organometallic chemistry and Shanghai Hongkong Joint Laboratory in Chemical SynthesisCenter for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China Chang-Kung Chuang Institute East China Normal UniversityShanghai 200062China

Alkynes are versatile synthons in organic synthesis,as well as important structural moieties in bioactive molecules.Recently,transition metal-catalyzed hydroalkynylation of alkenes has been developed with reactive alkenes and alkenes bearing directing groups.However,the regioselective hydroalkynylation of simple alkenes is still challenging.Herein,we have developed a palladium-catalyzed Markovnikov hydroalkynylation of unactivated terminal alkenes,which provides an efficient approach for the synthesis of branched alkynyl compounds under mild conditions.This reaction features excellent functional group tolerance,good reaction yields and excellent regioselectivity.Moreover,the asymmetric hydroalkynylation reaction has also been achieved with moderate enantioselectivity by introducing a sterically bulky chiral Pyox ligand.

关键词： Palladium catalysis Alkynylpalladation Unactivated terminal alkenes Markovnikov hydroalkynylation