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Influence of intramolecular substitution reaction of square planar carbonyl rhodium(Ⅰ)cationic complex on its stability

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chinese Science Bulletin 1999年第13期44卷 1195-1198页

作者： jiang Hua, pan Pinglai and YUAN Guoqinginstitute of chemistry, chinese academy of sciences , beijing 100080, china Corresponding author institute of Chemictry Chinese Academy of Sciences Beging China

Two cis-dicarbonyl rhodium complexes containing uncoordinated donors have been synthesized, and their IR and XPS data and the influence of their intramolecular substitution reaction on their stabilities have been reported. The intramolecular substitution reaction is reversible. Under the condition of heating and without the protection of CO, the uncoordinated donors substitute the terminal carbonyls on the rhodium to form tetradentated complex. So the rhodium complex will not decompose for the drop of the terminal carbonyls and its stability is enhanced. In atmosphere of CO, it recovers to bidentate complex.

关键词： rhodium complex intramolecular substitution stability.

Synthesis and Effect of Cation Binding on Photophysical Properties of 1,8-Anthraceno-18-Crown-5

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chinese Chemical Letters 1999年第12期10卷 0-0,0-0页

作者： Hua jiang Hui Jun XU Pei Jie XIA qing Fu ZHOU(Laboratory of Photochemistry, institute of Photographic chemistry,chinese academy of sciences, beijing 100101) chinese Acad Sci Inst Photog Chem Lab Photochem Beijing 100101 Peoples R China

A new type of anthracene crown ether 1, 8-anthraceno-18-crown-5 has been synthesizedand the photophysical properties upon complexation with alkali and alkaline-earth metal canonswere investigated. The fiuorescence quantum yield and lifetime are appreciably enhanced, and thestability constant Ks were determined by fluorometric titration. It was found that the magnitude ofKs is controlled by the size and charge density of the complexed canons.

关键词： Crown ether photophysical property canon-binding.

SYNTHESIS OF LADDERLIKE POLYHYDROXYPROPYLSILSESQUIOXANE

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chinese Journal of Polymer Science 2000年第5期18卷 453-457页

作者： Huai-zhong pan Chun-qing Liu Zhong Jin Ming Cao Jian-hua Luo Ping Xie Rong-ben Zhang Yu-hui Lin Neal Tai-sheng Chung Center for Molecular Science, institute of chemistry, chinese academy of sciences, beijing 100080, china institute of Materials Research and Engineering, Singapore 117602, Singapore chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China Inst Mat Res & Engn Singapore 117602 Singapore

Ladderlike polyhydroxypropylsilsesquioxane (HO-T) was synthesized by alcoholysis of ladderlike poly(3-propionyloxy-propyl)silsesquioxane. The HO-T was characterized by GPC, IR, NMR, DSC, TGA and X-ray diffraction methods. Through hydrogen-bonding interaction, ladderlike polymer (HO-T) can form a supramolecular complex with somewhat regular structure.

关键词： ladderlike polyhydroxypropylsilsesquioxane hydrogen-bond interaction supermolecular complex

Preparation and Structure-Property Regulation Mechanism of Reversible Thermochromic Polydiacetylene

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chinese Journal of Polymer Science 2024年第8期42卷 1111-1121页

作者： Zhi-qing Ge Shuo Yan Zu-Xiong pan Shan Lei Xuan-Zhi Mao Chu Zhao Mo-Zhen Wang Xue-Wu Ge Key Laboratory of Precision and Intelligent chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Marshall Laboratory of Biomedical Engineering International Cancer CenterLaboratory of Evolutionary Theranostics(LET)School of Biomedical EngineeringShenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China Shanghai institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of chinese academy of sciences Beijing 100049China

The thermochromic mechanism and the structure-property regulation principle of reversible thermochromic polydiacetylene(PDA)materials have always been a challenging *** this work,a series of diacetylene monomers(m-PCDA)containing phenyl and amide or carboxyl groups were synthesized from 10,12-pentacosadiynoic acid(PCDA)through the esterification or amidation *** effects of the number and the distribution of the functional groups in m-PCDA molecules on their solid-state polymerization capability,and the thermochromic mechanism of their corresponding polymers(m-PDA)were investigated and discussed in *** results show that the m-PCDA monomers containing both benzene ring and groups that can form hydrogen bonding interactions have strong intermolecular interaction,and are easy to carry out the solid phase polymerization under 254-nm UV irradiation to obtain the corresponding new thermochromic m-PDA *** thermochromic behavior of m-PDA depends on its melting *** initial color-change temperature(blue to red)is determined by the onset melting tem perature,and the temperature range in which reversible color recovery can be achieved by repeat heating-cooling treatment is determined by its melting *** to the proposed thermochromic mechanism of PDA,various new PDA materials with precise thermochromic temperatu res and reversible thermochromic temperature ra nges can be designed and synthesized through the appropriate introduction of benzene ring and groups that can form hydrogen bonding interactions into the molecular structure of linear diacetylene *** work provides a perspective to the precise molecular structure design and the property regulation of the reversible thermochromic PDA materials.

关键词： Polydiacetylene Thermochromism Hydrogen bonding Chemical modification

Synthesis of a Soluble Diacetylene with Phenylimidazole Ring

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Chemical Research in chinese Universities 2000年第4期16卷 324-327页

作者： WANG jiang-hong, CAO Ya-an, CAO Chang-sheng, SHI Yan-hui SHONG qing, WANG Li-jun and YAO Jian-nian (institute of Photographic chemistry, chinese academy of sciences, beijing 100101, P. R. china Department of chemistry, Jilin University, Changchun 130023, chinese Acad Sci Inst Photog Chem Beijing 100101 Peoples R China Jilin Univ Dept Chem Changchun 130023 Peoples R China chinese Acad Sci Changchun Inst Opt Fine Mech & Phys Changchun 130021 Peoples R China chinese Acad Sci Lab Excited State Proc Changchun 130021 Peoples R China

6-(2-Methyl-4-phenyl)-N-imidazole-2, 4-hexadiyn-1-ol was synthesized in a good yield by asymmetric coupling, and the corresponding intermediates were also prepared. The diacetylene monomer could be dissolved in common organic solvents. In addition, all kinds of conditions were also discussed effectively improving the formation of the diacetylene monomer.

关键词： Asymmetric coupling Phenylimidazole Ring Polydiacetylene

Multiomics analyses of two Leonurus species illuminate leonurine biosynthesis and its evolution

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Molecular Plant 2024年第1期17卷 158-177页

作者： Peng Li Meng-Xiao Yan pan Liu Dan-Jie Yang Ze-Kun He Yun Gao Yan jiang Yu Kong Xin Zhong Sheng Wu Jun Yang Hong-Xia Wang Yan-Bo Huang Le Wang Xiao-Ya Chen Yong-Hong Hu qing Zhao Ping Xu shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChineseAcademy of SciencesShanghaiChina College of Life sciences Shanghai Normal UniversityShanghai 200234China State Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina University of the chinese academy of sciences Beijing 100049China The Research Center of Chiral Drugs Innovation Research Institute of Traditional Chinese MedicineShanghai University of Traditional Chinese Medicine1200 Cailun RoadShanghai 201203China College of chemistry and Chemical Engineering Shanghai University of Engineering ScienceShanghai 201620China

The Lamiaceae family is renowned for its terpenoid-based medicinal components,but Leonurus,which has traditional medicinal uses,stands out for its alkaloid-rich ***,the principal active compound found in Leonurus,has demonstrated promising effects in reducing blood lipids and treating ***,the biosynthetic pathway of leonurine remains largely ***,we present the chromosome-level genome sequence assemblies of Leonurus japonicus,known for its high leonurine production,and Leonurus sibiricus,characterized by very limited leonurine *** integrating genomics,RNA sequencing,metabolomics,and enzyme activity assay data,we constructed the leonurine biosynthesis pathway and identified the arginine decarboxylase(ADC),uridine diphosphate glucosyltransferase(UGT),and serine carboxypeptidase-like(SCPL)acyltransferase enzymes that catalyze key reactions in this *** analyses revealed that the UGT–SCPL gene cluster evolved by gene duplication in the ancestor of Leonurus and neofunctionalization of SCPL in ***,which contributed to the accumulation of leonurine specifically in ***,our comprehensive study illuminates leonurine biosynthesis and its evolution in Leonurus.

关键词： Lamiaceae Leonurus japonicus Leonurus sibiricus genome sequence alkaloids leonurine gene cluster biosynthetic pathway evolution

Optimizing high-coordination shell of Co-based single-atom catalysts for efficient ORR and zinc-air batteries

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Journal of Energy chemistry 2024年第8期95卷 306-314,I0007页

作者： Yugang Qi qing Liang Kexin Song Xinyan Zhou Meiqi Liu Wenwen Li Fuxi Liu Zhou jiang Xu Zou Zhongjun Chen Wei Zhang Weitao Zheng Key Laboratory of Automobile Materials MOE School of Materials Science&Engineering Electron Microscopy Centerand International Center of Future ScienceJilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy MaterialsJilin UniversityChangchun 130012JilinChina institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Atom-level modulation of the coordination environment for single-atom catalysts(SACs)is considered as an effective strategy for elevating the catalytic *** the MNxsite,breaking the symmetrical geometry and charge distribution by introducing relatively weak electronegative atoms into the first/second shell is an efficient way,but it remains challenging for elucidating the underlying mechanism of ***,a practical strategy was reported to rationally design single cobalt atoms coordinated with both phosphorus and nitrogen atoms in a hierarchically porous carbon derived from metal-organic frameworks.X-ray absorption spectrum reveals that atomically dispersed Co sites are coordinated with four N atoms in the first shell and varying numbers of P atoms in the second shell(denoted as Co-N/P-C).The prepared catalyst exhibits excellent oxygen reduction reaction(ORR)activity as well as zinc-air battery *** introduction of P atoms in the Co-SACs weakens the interaction between Co and N,significantly promoting the adsorption process of ^(*)OOH,resulting in the acceleration of reaction kinetics and reduction of thermodynamic barrier,responsible for the increased intrinsic *** discovery provides insights into an ultimate design of single-atom catalysts with adjustable electrocatalytic activities for efficient electrochemical energy conversion.

关键词： Electrocatalytic Oxygen reduction reaction Single atom catalyst Shell coordination optimization

A Minor New Diterpenoid Alkaloids from the Roots of Delphinium Souliei Franch

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chinese Chemical Letters 1999年第12期10卷 0-0页

作者： Lan HE Yuan jiang pan Bo Gang LI Yao Zu CHEN(1Department of chemistry, beijing Normal University, beijing, 100085)(2 Department of chemistry, Zhejiang University, Hangzhou 310027)(3The Chengdu institute of Biology, chinese academy of sciences, Chengdu beijing Normal Univ Dept Chem Beijing 100085 Peoples R China Zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China chinese Acad Sci Chengdu Inst Biol Chengdu 610041 Peoples R China

A minor new diterpenoid alkaloid, soulidine, was isolated from the roots of DelphiniumSouliei Franch, its structure was established on the basis of spectral evidences.

关键词： DeIPhinium souliei new deterpenoid alkaloid soulidine spectral data.

Dangling Ligand Enables an Iron Hexa-Coordinated Molecular Catalyst for Water Oxidation by Photocatalysis

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CCS chemistry 2024年第3期6卷 623-630页

作者： Bing Yang Qi Liu Xiang-Zhu Wei Tao Lei qing-qing Yang Xu-Zhe Wang Jing-Xin Jian Xin jiang Chen-Ho Tung Li-Zhu Wu Key Laboratory of Photochemical Conversion and Optoelectronic Materials New Cornerstone Science LaboratoryTechnical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190 School of Future Technology University of Chinese Academy of SciencesBeijing 100049

Photocatalytic water oxidation reaction by transition metal complexes remains a challenge because of their poor stability under irradiation,especially for earth-abundant metal *** this regard,ironbased water oxidation catalysts are prone to hydrolysis and/or dissociate the ligands to form nanoparticles under a real catalytic ***,we describe a unique hexa-coordinated catalyst 1[Fe^(II)(Py_(3)tacn)Cl_(2)]and its reference 2[Fe^(II)(PhPy_(2)tacn)Cl_(2)]with a dangling pyridyl ligand and a phenyl group,*** anticipated that the dynamically open and close coordination behaviors of the pyridyl ligand enabled balance of the reactivity and stability of catalyst *** our delight,the“open form”of catalyst 1 provided a free coordination site,and the“close form”guaranteed its molecular integrity,resulting in a water oxidation reaction with high efficiency and *** turnover number and turnover frequency values of 2332 and 60 s^(−1)are the highest known to date among iron-based homogeneous water oxidation systems under visible light irradiation.

关键词： water oxidation photocatalysis homogeneous catalysis iron complexes dangling ligand intermediates characterization