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Synthesis of 2-methylpyrazine from cyclocondensation of ethylene diamine and propylene glycol over promoted copper catalyst

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Chinese Chemical Letters 2008年第6期19卷 752-755页

作者： Fang Li Jing Wei Chu Yuan Yuan Zhang Ye Qiang Chen Shi Zhong Luo Department of Chemical Engineering Sichuan University Chengdu 610065 China College of Materials Science and Chemical Engineering Zhejiang University Hangzhou 310027 China

The 2-methylpyrazine was synthesized by catalytic reaction of ethylene diamine and propylene glycol at 380 ℃. The alumina supported copper catalysts with promoter were prepared by impregnation method, characterized by ICP-AES, BET and TPR. The results demonstrated that the dehydrogenation was improved by addition of chromium promoter. The selectivity of 2-methylpyrazine reached 84.75%, while the conversions of reactants were also enhanced.

关键词： 2-Methylpyrazine copper catalyst Dehydrogenation Ethylene diamine Propylene glycol Promoter

Remote copper-catalyzed enantioselective substitution of yne-thiophene carbonates

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Science China Chemistry 2024年第4期67卷 1175-1180页

作者： Hao-Dong Qian Xiang Li Tingrui Yin Wei-Feng Qian Chunhui Zhao Cuiju Zhu Hao Xu CCNU-uOttawa Joint Research Centre Key Laboratory of Pesticides&Chemical Biology of Ministry of EducationInternational Joint Research Center for Intelligent Biosensing Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhan 430079China

Here,we describe a strategy for the copper-catalyzed asymmetric heteroarylation of yne-thiophene carbonates with indoles via remote *** key to the success of this strategy lies in the design of the alkynyl group at the ortho-position of the heterocycle thiophene,enabling the formation of a triarylmethane moiety via very remote ***,the concept of remote copper-catalyzed asymmetric transformation extends not only to yne-allylic esters but also to yne-aryl *** reaction readily provides a diverse array of chiral triarylmethanes with high efficiency,enantioselectivity,and excellent functional group ***,facile follow-up transformations underscore their potential utility in the synthesis of various enantioenriched building *** mechanistic studies support the plausibility of the remote substitution pathway.

关键词： remote substitution copper catalyst asymmetric catalysis triaryl methanes

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Methanol steam reforming for hydrogen production driven by an atomically precise Cu catalyst

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Green Energy & Environment 2024年第07期9卷 1079-1084页

作者： Weigang Hu Haoqi Liu Yuankun Zhang Jiawei Ji Guangjun Li Xiao Cai Xu Liu Wen Wu Xu Weiping Ding Yan Zhu School of Chemistry and Chemical Engineering Nanjing University School of Physical Science and Technology Ningbo University

Plasmon-induced hot-electron transfer from metal nanostructures is being intensely pursed in current photocatalytic research,however it remains elusive whether molecular-like metal clusters with excitonic behavior can be used as light-harvesting materials in solar energy utilization such as photocatalytic methanol steam *** this work,we report an atomically precise Cu13cluster protected by dual ligands of thiolate and phosphine that can be viewed as the assembly of one top Cu atom and three *** Cu13H10（SR）3（PR’3）7(SR=2,4-dichlorobenzenethiol,PR’3=P（4-FC6H4）3) cluster can give rise to highly efficient light-driven activity for methanol steam reforming toward H2production.

关键词： Nanocluster Photocatalysis Methanol steam reforming Atomically precise copper catalyst

POLYKETONE FROM ETHYLENE WITH CARBON MONOXIDE CATALYZED BY NOVEL catalyst SYSTEMS BASED ON copper WITH BIDENTATE PHOSPHORUS CHELATING LIGANDS

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Chinese Journal of Polymer Science 2003年第4期21卷 479-482页

作者：彭国卿 Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Copolymerization of ethylene with carbon monoxide was pertormed with Cu catalyst systems. Novel catalystsystems based on Cu (Cu(CH_3COO)_2/ligand/acid) were firstly reported for the copolymerization of ethylene with carbonmonoxide, in which the ligand was a bidentate phosphorus chelating ligand. The experimental results showed that this kindof Cu catalyst system exhibited high activity. When DPPP (1, 3-bis(diphenylphosphine)propane) and CH_3COOH were usedas ligand and acid, the corresponding catalyst system had the best activity of 108.1 g copolymer/(gCu·h). The novel Cu catalyst system had the advantages of high stability and low cost.

关键词： copper catalyst Copolymerization Ethylene Carbon monoxide Polyketone

Generation and transformation ofα-oxy carbene intermediates enabled by copper-catalyzed carbonylation

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Green Carbon 2024年第1期2卷 70-80页

作者： Yang Yuan Xiao-Feng Wu Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of Sciences116023 DalianLiaoningChina Leibniz-Institut für Katalyse e.V. Albert-Einstein-Straße 29a18059 RostockGermany

Since the Fischer-Tropsch reaction was discovered by Otto Roelen in 1938,transition metal-catalyzed carbo-nylation reactions come in as one of the most important methods for preparing carbonyl-containing and carbon chain-increased *** a result,the field of carbonylation research has received considerable attention over the past decades and continues to *** the continuous development of carbonylation and the in-depth study of the mechanism,more mechanistic details and variations have been revealed,which provide more possibilities for organic ***,copper catalysis has been introduced to the carbonylative functio-nalization of alkenes,thus enabling the rapid assembly of functionalized carbonyl compounds from simple starting *** this Account,we summarize the new findings in the Cu-catalyzed borocarbonylation of alkenes based on the generation and transformation ofα-oxy carbene *** believe that the results presented in this Account will further inspire the design of new carbonylation reactions.

关键词： Carbonylation copper catalyst Carbene Carbon monoxide Domino reaction

气固界面聚合反应制备晶圆级均匀超薄二维有机薄膜

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Science China Materials 2022年第6期65卷 1577-1585页

作者：姚文乾杨贺张卿菘施龙献孙健哲郭云龙江浪武斌刘云圻 Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China Sino-Danish Center for Education and Research Sino-Danish CollegeUniversity of Chinese Academy of SciencesBeijing 100049China

本文介绍了一种利用气固界面聚合反应制备大面积均匀超薄二维有机分子薄膜的新进展.通常有机分子薄膜的制备多借助于溶液法、旋涂法等技术,所制备的薄膜尺寸、均匀性和厚度可控性较差.传统的化学气相沉积法在大面积石墨烯、氮化硼、过... 详细信息

本文介绍了一种利用气固界面聚合反应制备大面积均匀超薄二维有机分子薄膜的新进展.通常有机分子薄膜的制备多借助于溶液法、旋涂法等技术,所制备的薄膜尺寸、均匀性和厚度可控性较差.传统的化学气相沉积法在大面积石墨烯、氮化硼、过渡金属硫族化合物等二维材料的制备方面应用广泛,但在有机分子薄膜制备领域却鲜有报道.本文中,我们展示了一种基于化学气相沉积生长连续、均匀、超薄(2-5 nm)的晶圆级多晶有机薄膜的一般方法.该方法基于铜表面催化的一系列含溴π-共轭小分子的聚合,其中局部表面聚合和有机分子内部π-π相互作用决定了薄膜的尺寸和均匀性,研究表明薄膜的生长形貌和速度与铜晶面的类型密切相关,基于此在Cu(111)表面获得了更为均匀的薄膜.通过另外两种有机小分子薄膜的制备有效地证明了该方法的可拓展性.该方法为基于难溶性有机小分子可控制备大面积原子厚度薄膜和相关异质结构,如有机膜/石墨烯,及其他功能材料和器件提供了新空间.

关键词： organic films interface chemical vapor deposition copper catalyst debromination

揭示和调控二氧化碳电还原中甲烷与二碳产物的线性关系

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Science Bulletin 2022年第10期67卷 1042-1048,M0004页

作者：刘坤豪杨超韦瑞麟马星宇彭陈刘铮铮陈杨屾严雅琴阚淼阳耀月郑耿锋 Laboratory of Advanced Materials Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFaculty of Chemistry and Materials ScienceFudan UniversityShanghai 200438China College of Chemistry and Environmental Protection Engineering Southwest Minzu UniversityChengdu 610041China

尽管许多催化剂已经被报道用于电化学转换二氧化碳(CO_(2))到甲烷(CH_(4))或者二碳(C_(2))产物,然而目前对各种产物之间的关联的研究仍然不够深入,这阻碍着催化剂设计的进一步发展.本文通过研究商品化铜粉(Cu)作为CO_(2)电还原的阴极催... 详细信息

尽管许多催化剂已经被报道用于电化学转换二氧化碳(CO_(2))到甲烷(CH_(4))或者二碳(C_(2))产物,然而目前对各种产物之间的关联的研究仍然不够深入,这阻碍着催化剂设计的进一步发展.本文通过研究商品化铜粉(Cu)作为CO_(2)电还原的阴极催化剂,发现一氧化碳中间体(*CO)在催化剂表面的覆盖度在较大的电位区间内会保持基本不变,且在这个电位区间内,CH_(4)与C_(2)产物的分电流密度呈线性关系,这一结论得到了理论动力学分析的支持.由于*CHO中间体分子是产生CH_(4)(*CHO→CH_(4))与C_(2)产物(*CHO+*CO→C_(2))的共同中间体,我们进一步猜想该线性关系是普遍存在的,且可以通过调节催化剂表面的吸附氢(*H)或者一氧化碳(*CO)的覆盖度,以分别促进CH_(4)或者C_(2)产物的生成,并改变线性关系的斜率.为了验证该猜想,本文合成了碳包覆的铜(Cu@C)催化剂,其中碳层可增加催化剂表面的*H覆盖度从而提高CH_(4)的产生,最高的CH_(4)法拉第效率(FE_(CH_(4)))达到52%,相应的分电流密度为±337 m A cm±2.另一方面,合成了银掺杂的铜催化剂,其中掺杂的银用以产生CO,以进一步提高催化剂表面的*CO覆盖度.该催化剂二氧化碳电还原的选择性变成了C_(2)产物为主,最高C_(2)产物的法拉第效率(FE_(CH_(4)))达到79%,相应的分电流密度为±421 m A cm±2.不仅如此,在这两种催化剂上,CH_(4)与C_(2)产物的分电流密度仍然保持良好的线性关系.本文工作揭示了CH_(4)与C_(2)产物产率的线性关系,以及反应中间分子的调控策略,为电催化二氧化碳还原为不同的产物提供了参考.

关键词： Electrochemical CO_(2)reduction copper catalyst Reaction pathway CO coverage Linear correlation

Effect of tungsten oxide on ceria nanorods to support copper species as CO oxidation catalysts

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Journal of Rare Earths 2021年第1期39卷 43-50,I0002页

作者： Yu'nan Li Lin Gan Rui Si Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials and School of Material Science and EngineeringHubei UniversityWuhan 430062China Zhangjiang Laboratory Shanghai Synchrotron Radiation FacilityShanghai 201204China

In this work,tungsten oxide with different concentrations(0,0.4 at%,2.0 at%and 3.2 at%)was introduced to the ceria nanorods via a deposition-precipitation(DP)approach,and copper species of ca.10 at%were sequentially anchored onto the modified ceria support by a similar DP *** aim of the study was to investigate the effect of the amount of tungsten oxide(0,0.4 at%,2.0 at%,and 3.2 at%)modifier on the copper-ceria catalysts for CO oxidation reaction and shed light on the structure-activity *** the aids of multiple characterization techniques including N2 adsorption,high-resolution transmission electron microscopy(HRTEM),powder X-ray diffraction(XRD),X-ray absorption fine structure(XAFS),and temperature-programmed reduction by hydrogen(H2-TPR)in combination with the catalytic performance for CO oxidation reaction,it is found that the copper-ceria samples maintain the crystal structure of the fluorite fcc CeO2 phase with the same nanorod-like morphology with the introduction of tungsten oxide,while the textural properties(the surface area,pore volume and pore size)of ceria support and copper-ceria catalysts are changed,and the oxidation states of copper and tungsten are kept the same as Cu2+and W6+before and after the reaction,but the introduction of tungsten oxide(WO3)significantly changes the metal-support interaction(transfer the CuOx clusters to Cu-[Ox]-Ce species),which delivers to impair the catalytic activity of copper-ceria catalysts for CO oxidation reaction.

关键词： copper catalyst Ceria Tungsten oxide CO oxidation Structure-activity relationship Rare earths

Environmental Friendly Azide-Alkyne Cycloaddition Reaction of Azides, Alkynes, and Organic Halides or Epoxides in Water： Efficient ＂Click＂ Synthesis of 1,2,3-Triazole Derivatives by Cu catalyst

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Chinese Journal of Chemistry 2012年第3期30卷 644-650页

作者：刘建明刘慕文岳园园姚美焕卓克垒 Key Laboratory of Green Chemical Media and Reactions(Ministry of Education) School of Chemistry and Environmental ScienceHenan Normal UniversityXinxiangHenan 453007China

An efficient click synthesis of 1,2,3-triazole derivatives from benzyl halides or alkyl halides, epoxides, terminal alkynes, and sodium azides in the presence of copper salts and relative benzimidazole salts have been developed. This procedure eliminates the need to handle potentially organic azides, which are generated in situ. A broad spec- trum of substrates can participate in the process effectively to produce the desired products in good yields.

关键词： copper catalyst benzimidazole salts 1,2,3-triazole derivatives click chemistry cycloaddition