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Asymmetric Access of γ-Amino Acids and γ-Amino Phosphonic Acid Derivatives via copper-Catalyzed Enantioselective and Regioselective Hydroamination

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CCS Chemistry 2022年第6期4卷 1901-1911页

作者： Zhiping Yang Qingwei Du Yanxin Jiang Jun(Joelle) Wang Harbin Institute of Technology Harbin 150001 Department of Chemistry Southern University of Science and Technology(SUSTech)Shenzhen 518055 Department of Chemistry Hong Kong Baptist UniversityKowloonHong Kong 999077

γ-Aminobutyric acid is a major inhibitory neurotransmitter in the mammalian central nervous system that plays a substantial role in brain disorders.γ-Amino phosphonic acid is a unique surrogate of both natural and unnatural γ-amino acid.Because of their unique biological activity,γ-amino acid and γ-amino phosphonic acid derivatives have attracted considerable attention.However,an efficient and straightforward method for constructing chiral γ-substituted-γ-amino acid and γ-amino phosphonic acid derivatives remains a long-standing challenge.Herein,a highly efficient,versatile,and universal Cucatalyzed asymmetric hydroamination of cinnamyl esters,cinnamyl phosphonates,and cinnamyl phosphine oxides is presented for accessing γ-amino acid andγ-amino phosphonic acid derivatives in good yields with high levels of enantiocontrol and regioselectivity.

关键词： asymmetric catalysis copper hydroamination γ-amino acid amino phosphine

Electrochemical Approaches to CO_(2) Conversion on copper-Based Catalysts

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Accounts of Materials Research 2023年第3期4卷 212-222页

作者： Gong Zhang Lulu Li Zhi-Jian Zhao Tuo Wang Jinlong Gong School of Chemical Engineering and Technology Key Laboratory for Green Chemical Technology of Ministry of EducationTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China

CONSPECTUS:As one of the essential pathways to carbon neutrality or carbon negativity,the electrochemical reduction of CO_(2) offers tremendous prospects for platform chemicals and fuel production.copper(Cu)is currently the only metal material that is able to reduce CO_(2) to multicarbon(C2+)products.Despite the fact that copper-based materials have been investigated for decades,we still confront numerous challenges on the path to the fundamental understanding and large-scale deployment of copper-based electrocatalysts for CO_(2) reduction.For fundamental investigations,it remains a variety of open questions about the CO_(2) reduction mechanisms.The convoluted C−C coupling pathways and product bifurcation processes confuse the design of efficient catalysts.The active sites of copper-based catalysts remain ambiguous due to surface reconstruction.As for theoretical calculations,the construction of electrolyte−electrode models and the investigation of solvation effects are premature for obtaining confident conclusions.In addition,simple and easily scalable techniques for catalyst synthesis still need to be continuously developed.For practical applications,the CO_(2) electrolyzer with copper-based materials must be operated with high current densities,high Faradaic efficiencies,high energetic efficiencies,high single-pass conversion rates(high product concentration),and long stability.Nevertheless,due to the intricate nature of electrochemical systems,a high-performance copper-based electrocatalyst alone is not sufficient to meet all of the above commercialization requirements.Therefore,reactor design involving mass transfer enhancement calls for more research input.Based on the above background and the urgency of the net-zero goal,we initiated our research on CO_(2) electrolysis using copper-based materials with an emphasis on active site identification and mass transfer enhancement.This Account describes our contribution to the field of C_(2+)products formation.We first discuss the synthesis of copper-based materia

关键词： stability catalyst copper

Shape-Controlled Synthesis of copper Nanocrystals for Plasmonic,Biomedical,and Electrocatalytic Applications

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Accounts of Materials Research 2022年第11期3卷 1137-1148页

作者： Zhiheng Lyu Yuxin Shang Younan Xia School of Chemistry and Biochemistry Georgia Institute of TechnologyAtlantaGeorgia 30332United States The Wallace H.Coulter Department of Biomedical Engineering Georgia Institute of Technology and Emory UniversityAtlantaGeorgia 30332United States School of Chemical and Biomolecular Engineering Georgia Institute of TechnologyAtlantaGeorgia 30332United States

CONSPECTUS:As a metal that can occur in nature in the elemental form,copper(Cu)has been used by humans since ca.8000 BC.With most properties matching those of Ag and Au,Cu has played a more significant role in commercial applications owing to its much higher(the 25th among all elements)abundance in Earth’s crust and thus more affordable price.In addition to its common use as a conductor of heat and electricity,it is a constituent of various metal alloys for hardware,coins,strain gauges,and thermocouples.

关键词： alloys copper gauge

Ceramic-copper substrate technology introduction

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China Welding 2022年第2期31卷 56-64页

作者：赵清清孙文韬 WLP&TPAK department Shenzhen STS Microelectronics Co-LtdShenzhen 518000China Quality department Shenzhen STS Microelectronics Co-LtdShenzhen 518000China

Ceramic-copper substrate is used to achieve the combination between copper and ceramic(Al_(2)O_(3) or AlN)under high temperatures by bonding or brazing process,then through dedicate lamination–etching technology to develop the designed layout in copper surface,finally parts go with plating and singulation process for surface treatment before shipping to the end-user.Ceramic-copper substrate has perfect performance in terms of insulation,thermal conductivity,solderability,and adhesion strength.Besides,the copper on surface can afford huge current due to the fact that ceramic has good reliability and thermal-cycling performance.According to technical visit and audit to suppliers’manufacturing process and based on several years’experience of mass production for electric vehicle power module package,this article introduces two mainstream ceramic-copper substrate processing methods currently on the market:direct bond copper(DBC)and active metal brazing(AMB)which can be widely used for the intelligent power module and electric vehicle power module,also introduces the major failure mode during application and analyzes the root cause for each failure mode,clarifies key incoming monitoring method,like crosshatch,silver plating thickness measurement and blister test.This article also clarifies the Incoming Quality Control system,which can provide guidance to process engineer during the application.

关键词： copper ceramic bonding/brazing power module

Adsorption Isotherm Study of Activated Fruit Peels for copper Removal

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Journal of Harbin Institute of Technology(New Series) 2022年第3期29卷 93-100页

作者： S.Y.Tai L.L.Fong M.K.Chan P.K.Bullar Centre for Water Research Faculty of EngineeringBuilt Environment and Information TechnologySEGi University Sdn BhdPetaling Jaya 47810SelangorMalaysia

Heavy metal polluted water threatens the integrity of ecosystem.The use of agricultural waste as adsorbent becomes popular due to its biodegradability and availability.However,limited research works has been done to process agricultural waste for heavy metal adsorption purpose.The objective of this study is to propose a new approach to treat banana peel using ZnCl_(2) prior to alkali and acid treatment and explore the potential of dragon fruit peels as the adsorbent for Cu^(2+)adsorption.Seven adsorption isotherm was adopted to identify the adsorption mechanism and four statistical parameters were calculated for model verification purpose.The experiment was conducted by dispersing ZnCl_(2) treated and untreated adsorbents into Cu^(2+) solution.Results showed that ZnCl_(2) treated adsorbents performed better in terms of Cu^(2+) removal compared with untreated adsorbents due to higher surface area for Cu^(2+) adsorption.The treated banana peel(Act.-B)performed approximately 30%better than the treated dragon fruit peel(Act.-D)due to the presence of hydroxyl and carboxyl groups.The equilibrium adsorptive capacity of Act.-B was 1872.8 mg Cu^(2+)/g and the experimental data fitted Freundlich isotherm well with R^(2)=0.9978,0.0161 of residual sum of error(SSE),0.0068 of χ^(2),and 0.0567 of root mean square error(RMSE)values.This suggests non⁃linear adsorption and multilayer adsorption on heterogenous surfaces.Thus,it is recommended to further improve the surface properties of Act.-B by steam pyrolysis and surface modification.

关键词： banana peel adsorbents dragon fruit peel adsorbents copper FTIR isotherm

Alternative copper-Based Single-Atom Nanozyme with Superior Multienzyme Activities and NIR-II Responsiveness to Fight against Deep Tissue Infections

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Research 2023年第3期6卷 409-421页

作者： Jiaxiang Bai Yonghai Feng Wenming Li Zerui Cheng Jessica MRosenholm Huilin Yang Guoqing Pan Hongbo Zhang Dechun Geng Department of Orthopedic Surgery Orthopedic InstituteThe First Affiliated HospitalMedical CollegeSoochow UniversitySuzhouJiangsu 215006P.R.China Institute for Advanced Materials School of Materials Science and EngineeringJiangsu UniversityZhenjiangJiangsu 212013P.R.China Pharmaceutical Sciences Laboratory Faculty of Science and EngineeringÅbo Akademi UniversityTurku 20520Finland Turku Bioscience Centre University of Turku andÅbo Akademi UniversityTurku 20520Finland

Nanozymes are considered to represent a new era of antibacterial agents,while their antibacterial efficiency is limited by the increasing tissue depth of infection.To address this issue,here,we report a copper and silk fibroin(Cu-SF)complex strategy to synthesize alternative copper single-atom nanozymes(SAzymes)with atomically dispersed copper sites anchored on ultrathin 2D porous N-doped carbon nanosheets(CuN_(x)-CNS)and tunable N coordination numbers in the CuN_(x) sites(x=2 or 4).The CuN_(x)-CNS SAzymes inherently possess triple peroxidase(POD)-,catalase(CAT)-,and oxidase(OXD)-like activities,facilitating the conversion of H_(2)O_(2)and O_(2)into reactive oxygen species(ROS)through parallel POD-and OXD-like or cascaded CAT-and OXD-like reactions.Compared to CuN_(2)-CNS,tailoring the N coordination number from 2 to 4 endows the SAzyme(CuN_(4)-CNS)with higher multienzyme activities due to its superior electron structure and lower energy barrier.Meanwhile,CuN_(x)-CNS display strong absorption in the second near-infrared(NIR-II)biowindow with deeper tissue penetration,offering NIR-II-responsive enhanced ROS generation and photothermal treatment in deep tissues.The in vitro and in vivo results demonstrate that the optimal CuN_(4)-CNS can effectively inhibit multidrug-resistant bacteria and eliminate stubborn biofilms,thus exhibiting high therapeutic efficacy in both superficial skin wound and deep implant-related biofilm infections.

关键词： copper offering eliminate

A copper-iodide cluster microcube-based X-ray scintillator

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Light(Science & Applications) 2023年第11期12卷 2261-2263页

作者： Jian Qiu Xiaogang Liu Joint School of the National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New City350207 FuzhouChina Department of Chemistry National University of SingaporeSingapore 117543Singapore Institute of Materials Research and Engineering Agency for ScienceTechnology and ResearchSingapore 138634Singapore

Newly developed copper-iodide cluster microcubes offer a solution to the issues commonly faced by powder scintillation screens.These problems include inadequate scintillation performance and significant light scattering,resulting in poor image quality.With the advent of monodisperse copper-iodide cluster microparticle scintillators,efficient and long-term stable scintillation is achieved,while ensuring biocompatibility.Moreover,they enable highresolution static and dynamic X-ray imaging,providing high image quality.

关键词： cluster copper disperse

copper-Catalyzed Modular Access to N-Fused Polycyclic Indoles and 5-Aroyl-pyrrol-2-ones via Intramolecular N-H/C-H Annulation with Alkynes:Scope and Mechanism Probes

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Chinese Journal of Chemistry 2020年第12期38卷 1545-1552页

作者： Yan-Hua Liu Hong Song Chi Zhang Yue-Jin Liu Bing-Feng Shi Department of Chemistry Zhejiang UniversityHangzhouZhejiang 310027China

of main observation and concusion copper-catalyzed intramolecular N-H/C-H annulation with alkynes has been developed.A vaniety ofdensely functionalized heterocycles,such as pyrrolo[1,2-a]indoles,indolo[1,2-c]quinazolin-2-ones,oxazolo[3,4-o]indoles,and imidazo[1.5-o]indoles,eresynthesized in an atom-and step-economical manner,owing to the high modularized feature of aniline moiety te linker moiety,as well as the alkynemoiety.By simply changing the oxidant from di-tert-butyl peroxide(DTBP)to 2,2,6.6-tetramethylpiperidine-1-oxyl(TEMPo)the reacton could readily betransformed to the aminooxygenation pathway,which grabs one oxygen atom from the TEMPO to generate 5-aroy'-pyrrol-2-ones.Mechanistic experi-ments indicate that viny radical is involved in this reaction and an amidyl-radical-initiated radical cascade might be responsible for this transformation.

关键词： moiety copper radical

copper Catalyzed Asymmetric [4＋2] Annulations of D-A Cyclobutanes with Aldehydes

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Chinese Journal of Chemistry 2018年第1期36卷 47-50页

作者： Jiang-Lin Hu Li Zhou Lijia Wang Zuowei Xie Yong Tang The State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China Shanghai-Hong Kong Joint Laboratory in Chemical Synthesis Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling RoadShanghai 200032 China Collaborative Innovation Center of Chemical Science and Engineering Tianjin China

copper catalyzed enantioselective [4＋2] annulations of D-A cyclobutanes and aldehydes have been developed. In the presence of a side arm modified chiral bisoxazoline （SaBOX） ligand, the [4＋2] annulations proceeded smoothly with a broad substrate scope. 22 examples were studied, leading to the corresponding products with various functional groups in 41%-99% yields with 〉99/1 dr and 90%-96% ee. The resulting product with two ester groups was mono-reduced, giving the corresponding product in excellent diastereoselectivity without loss of the enantiopurity.

关键词： [4＋2] annulation cyclobutane enantioselective copper bisoxazoline