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Directly Knitted Ruthenium Pincer Complexes with Enhanced Activity as Recyclable Single-Site Catalysts for Hydrogenation of CO_(2)to Methanol

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CCS Chemistry 2023年第7期5卷 1602-1611页

作者： Daheng Wen Jiangbo Chen qingshu zheng Siqi Yang Tao Tu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438 State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032 Green Catalysis Center and College of Chemistry Zhengzhou UniversityZhengzhou 450001

Considering the importance of the valorization of CO_(2),a number of phosphine-containing ruthenium pincer complexes have been successfully heterogenized using a“direct knitting”strategy without any *** resulting porous organometallic polymers(POMPs)with high specific-surface areas,hierarchical pores,and uniformly dispersed Ru single-sites exhibited outstanding catalytic activity toward the N-formylation of diverse amines with CO_(2).Besides excellent turnover number(TON,5×10^(5))and turnover frequency(TOF,5592 h-1),the obtained formamides were readily hydrogenated to methanol with the same ***,an amine-assisted direct hydrogenation system of CO_(2)to methanol was established by POMPs with higher activity and TON(1.46×10^(4))than their molecular precursors,shedding light on the direct valorization of CO_(2)and carbon neutral recycling.

关键词： direct knitting hydrogenation of CO_(2) porous organometallic polymers ruthenium pincer complexes single-site catalyst

Metallo-aerogels derived from chitosan with encapsulated metal nanoparticles as robust,efficient and selective nanocatalysts towards reduction of nitroarenes

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Nano Research 2021年第1期14卷 59-65页

作者： Yajing Shen qingshu zheng Jianhong Liu Tao Tu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan University2005 Songhu RoadShanghai 200438China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China College of Chemistry and Molecular Engineering Zhengzhou University100 Kexue avenueZhengzhou 450001China

A series of robust metallo-aerogels are readily fabricated by pyrolysis of xerogels derived from chitosan-metal(M=Fe,Co,Ni)*** to the strong coordination between metal ions and the functional groups(NH2 and OH)of chitosan,metallo-aerogels consisting of encapsulated metal-nanoparticles(MNPs)by graphite shells were obtained,as supported by various characterizations including high-resolution transmission electron microscope(HR-TEM),X-ray diffraction(XRD),and *** resulting metalloaerogels could be functioned as highly stable,efficient and selective nanocatalysts towards the hydrogenation of nitroarenes to amines at low catalyst loading(1.2 mol.%-2.4 mol.%).Remarkably,the metallo-aerogels could be reused for more than 30 runs without obvious loss of activity and *** distinguished performances were attributed to the graphitic shells formed during the pyrolysis,which hampered the possible aggregation of MNPs,prevented metal leaching and increased their stability.

关键词： metallo-aerogels nanocatalysts nitroarenes reduction pyrolysis

Hydrogen-bond-assisted transition-metal-free catalytic transformation of amides to esters

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Science China Chemistry 2021年第1期64卷 66-71页

作者： Changyu Huang Jinpeng Li Jiaquan Wang qingshu zheng Zhenhua Li Tao Tu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Green Catalysis Center and College of Chemistry Zhengzhou UniversityZhengzhou 450001China

The amide C-N cleavage has drawn a broad interest in synthetic chemistry,biological process and pharmaceutical ***-metal,luxury ligand or excess base were always vital to the ***,we developed a transition-metalfree hydrogen-bond-assisted esterification of amides with only catalytic amount of *** proposed crucial role of hydrogen bonding for assisting esterification was control experiments,density functional theory(DFT)calculations and kinetic *** broad substrate scopes and excellent functional groups tolerance,this base-catalyzed protocol complements the conventional transition-metal-catalyzed esterification of amides and provides a new pathway to catalytic cleavage of amide C–N bonds for organic synthesis and pharmaceutical industry.

关键词： amides C–N bond cleavage esterification hydrogen bonding transition-metal-free catalysis

Highly efficient NHC-iridium-catalyzedβ-methylation of alcohols with methanol at low catalyst loadings

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Science China Chemistry 2021年第8期64卷 1361-1366页

作者： Zeye Lu qingshu zheng Guangkuo Zeng Yunyan Kuang James H.Clark Tao Tu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai200438China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China Green Catalysis Center and College of Chemistry Zhengzhou UniversityZhengzhou450001China Green Chemistry Centre of Excellence University of YorkYorkYO 105DDUK

The methylation of alcohols is of great importance since a broad number of bioactive and pharmaceutical alcohols contain methyl ***,a highly efficientβ-methylation of primary and secondary alcohols with methanol has been achieved by using bis-N-heterocyclic carbene iridium(bis-NHC-Ir)*** substrate scope and up to quantitative yields were achieved at low catalyst loadings with only hydrogen and water as *** protocol was readily extended to theβ-alkylation of alcohols with several primary *** experiments,along with DFT calculations and crystallographic studies,revealed that the ligand effect is critical to their excellent catalytic performance,shedding light on more challenging Guerbet reactions with simple alcohols.

关键词： hydrogen-borrowing ligand effect iridium N-heterocyclic carbene methylation

Visual recognition of melamine in milk via selective metallo-hydrogel formation

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Chinese Chemical Letters 2019年第12期30卷 2266-2270页

作者： Xiaoling Bao Jianhong Liu qingshu zheng Wei Pei Yimei Yang Yanyun Dai Tao Tu Institute of Quality Inspection of Food and Cosmetics Shanghai Institute of Quality Inspection and Technical ResearchShanghai 200233China Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China

A series of novel six-coordinated terpyridine zinc complexes,containing ammonium salts and thymine fragment at the two terminals,have been designed and synthesized,which can function as highly sensitive visualized sensors for melamine detection via selective metallo-hydrogel *** fully characterization by various techniques,the complementary triple-hydrogen-bonding between the thymine fragment and melamine,as well as π-π stacking interactions may be responsible for the selective metallo-hydrogel *** light of the possible interference aroused by milk ingredients(proteins,peptides and amino acids) and legal/illegal additives(urine,sugars and vitamins),a series of control experiments are therefore *** our delight,this visual recognition is highly selective,no gelation was observed with the selected milk ingredients or ***,this new developed protocol enables convenient and highly selective visual recognition of melamine at a concentration as low as 10 ppm in raw milk without any tedious pretreatment.

关键词： Hydrogen-bonding interaction Pincer zinc complex Melamine Metallo-hydrogel Visual recognition

Colorimetric recognition of melamine in milk using novel pincer zinc complex stabilized gold nanoparticles

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Chinese Chemical Letters 2021年第10期32卷 3023-3026页

作者： Xiaoling Bao Jianhong Liu qingshu zheng Lixin Duan Yuzhu Zhang Junlong Qian Tao Tu Institute of Quality Inspection of Food and Cosmetics Shanghai Institute of Quality Inspection and Technical ResearchShanghai 200233China Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200232China College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhou 450001China

A convenient colorimetric approach for visual detection of melamine in raw milk was realized by using gold nanoparticles(AuNPs)stabilized by an unsymmetrical terpyridyl zinc complex with a thymine fragment at one terminal and a quaternary ammonium salt at the *** without pre-addition of melamine or relative additives,obvious color change from red to blue was observed by naked eye in the presence of trace amount of melamine,which was attributed to the alternation of aggregation state of AuNPs caused by the selective binding between the thymine fragment and melamine via triple hydrogenbonding ***,the detection limit for melamine was as low as 2.4 ppb,providing a highly sensitive and efficient approach for the visual detection of melamine.

关键词： Colorimetric recognition Gold nanoparticles Hydrogen-bonding interactions Pincer zinc complex Melamine

Robust NHC-palladacycles-catalyzed Suzuki-Miyaura cross-coupling of amides via C-N activation

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Green Synthesis and Catalysis 2020年第1期1卷 75-78页

作者： Qinyue Deng qingshu zheng Bin Zuo Tao Tu Department of Chemistry Fudan UniversityShanghai 200438China College of Science University of Shanghai for Science and TechnologyShanghai 200093China

Robust NHC-palladacycles(NHC¼N-heterocyclic carbene)were synthesized and exhibited high catalytic activity towards SuzukiMiyaura cross-coupling reactions between inactive amides with N-acetyl/benzyl substituents and aryl boronic acids,producing diverse ketones in good to excellent *** unprecedented and practical palladacycles-catalyzed SuzukiMiyaura cross-coupling of amides with boronic acids via selective C-N bond activation was attributed to the strongσ-donor and weakπ-acceptor properties of acenaphthoimidazolylidene,which may highlight their potential in other challenging coupling transformations involving inactive amides.

关键词： Aryl boronic acids C-N activation Inactive amides NHC-Palladacycle SuzukiMiyaura cross-coupling

配位组装构筑的磁性核壳复合材料促进CO_(2)高值催化转化

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Chinese Journal of Catalysis 2023年第5期48卷 258-266页

作者：李金鹏陈洁郑庆舒屠波涂涛复旦大学化学系上海市分子催化和功能材料重点实验室上海200438 中国科学院上海有机所有机金属化学国家重点实验室上海200032 郑州大学化学学院绿色催化中心河南郑州450001

自负载策略作为一种理想的分子催化剂负载方法引起了研究者的广泛关注.该制备策略会得到无定型的块状固体催化材料,导致大量活性催化中心被包埋在材料基体内部,使得反应底物难以靠近催化中心,从而降低了材料的催化效率.形貌调控被认为... 详细信息

自负载策略作为一种理想的分子催化剂负载方法引起了研究者的广泛关注.该制备策略会得到无定型的块状固体催化材料,导致大量活性催化中心被包埋在材料基体内部,使得反应底物难以靠近催化中心,从而降低了材料的催化效率.形貌调控被认为是增强固体催化材料活性和相应功能的有效策略之一.其中,球状形貌的磁性四氧化三铁纳米颗粒(Fe_(3)O_(4)NPs)因其比表面积较大、来源广泛和较好的磁响应性能而被广泛应用.在已知文献中,催化剂往往是通过后修饰策略进行负载的,但由于负载位点随机、配位模式不明确以及金属易流失等原因,相应负载催化材料的催化活性大大降低.利用配位组装策略对磁性纳米颗粒进行包覆是当前制备球状核壳型自负载复合催化材料的可行方法之一.考虑到三维材料具有多孔结构和更大的比表面积,有利于气体吸附和传质传热,因此可以作为磁性纳米颗粒理想的包覆材料.本文利用四齿咪唑盐和金属(铱或钯)前体,通过原位配位组装包覆策略对Fe_(3)O_(4)NPs直接进行包覆,制备了一系列磁性核壳结构复合型自负载固体分子催化材料.扫描电子显微镜和透射电子显微镜结果表明,此类复合材料呈现出明显的球状核壳结构,其中氮杂环卡宾金属配位聚合物均匀地包覆在磁性Fe_(3)O_(4)NPs表面.能量色散X射线光谱和球差电镜结果表明,金属均匀分散在整个复合材料基质中.X射线光电子能谱显示,包覆后金属的配位环境与相应均相催化剂没有明显改变.N_(2)和CO_(2)吸附结果表明,本文催化材料相比于相应的无定型自负载催化材料具有更大的比表面积和更高的CO_(2)吸附能力.利用CO_(2)加氢和脱氢反应对复合材料的催化性能进行测试,均显示出优于相应均相催化剂和自负载催化材料的催化活性.其中,在CO_(2)加氢制备甲酸的反应中,得到较好的多相催化体系转化数(1.69×10^(6)TON).此外,在甲酸铵脱氢反应中,催化材料可以通过磁性回收循环使用超过11次.进一步对Fe_(3)O_(4)NPs和无定型自负载催化材料的简单物理混合物进行了活性测试,发现只能得到与无定型自负载催化材料类似的催化效果,表明球状核壳结构对复合材料催化性能具有提升作用.综上,本文不仅通过包覆策略实现了催化材料的形貌调控,而且提升了自负载固体分子催化材料的催化性能,为CO_(2)高值化和氢气的存储和释放提供了可能.

关键词： CO_(2)高值化配位组装形貌调控 N-杂环卡宾化合物磁性催化材料

Plate tectonics in the Archean:Observations versus interpretations

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Science China Earth Sciences 2024年第1期67卷 1-30页

作者： YongFei zheng School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Crust-Mantle Materials and Environment Chinese Academy of SciencesHefei 230026China Center of Excellence for Comparative Planetology Chinese Academy of SciencesHefei 230026China

Plate tectonics theory,established in the 1960s,has been successful in explaining many geological phenomena,processes and events that occurred in the ***,the theory has often struggled to provide a coherent framework in interpreting geological records in continental interior and Precambrian *** dealing with the relationship between plate tectonics and continental geology,continental interior tectonics was often separated from continental margin tectonics in the inheritance and development of their structure and *** separation led to the illusion that the plate tectonics theory is not applicable to Precambrian geology,particularly in explaining the fundamental geological characteristics of Archean *** this illusion does not mean that the Archean continental crust did not originate from a regime of plate tectonics,it led to the development of alternative tectonic models,often involving vertical movements under a regime of stagnant lid tectonics,including not only endogenous processes such as gravitational sagduction,mantle plumes and heat pipes but also exogenous processes such as bolide *** vertical processes were not unique to the Archean but persisted into the *** result from mantle poloidal convection at different depths,not specific to any particular *** the plate tectonics theory from the traditional kinematic model in the 20th century to a holistic kinematic-dynamic model in the 21st century and systematically examining the vertical transport of matter and energy at plate margins,it is evident that plate tectonics can explain the common geological characteristics of Archean cratons,such as lithological associations,structural patterns and metamorphic *** deciphering the structure and composition of convergent plate margins as well as their dynamics,the formation and evolution of continental crust since the Archean can be divided into ancient plate tectonics in the Preca

关键词： Plate tectonics Archean geology Continental origin Crustal reworking Plate interior Plate margin