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CCS Chemistry 2023年第5期5卷 1163-1175页

作者： Jun-Yan Wu Bin-Rui Mo Jin-Dong Yang Jin-Pei Cheng Department of Chemistry Tsinghua UniversityBeijing 100084 College of Chemistry Nankai UniversityTianjin 300071 Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192

Electronic and bonding situations at reaction centers are often detected by the remote substituent effect.For nonorganometallic reactions,this effect is conventionally described by the well-known Hammett-type substituent constants.However,for most transition metal(TM)-involved systems,no analogous numeral descriptors reflecting the intrinsic differences between metallic and nonmetallic bonding have been rigorously established till present.Herein,we report a Pd(II)–O bond heterolysis energyΔG_(het)(Pd–O)study of the archetypal palladium complexes to represent the thermodynamics of the essential bond-breaking step in Pd-mediated transformations.Meanwhile we furnish the new substituent constantsσPd^(+)s and therefrom facilitate linear free-energy relationship(LFER)analysis for Pd-catalyzed reactions.Indeed,this led us to find an unexpected electron-donating ability of Pd(II)cation,which provided a gifted experimental support,with the aid of computation,to attribute the frustrating observation of a much scattered curvature in theΔG_(het)(Pd–O)-σ+correlation to the electrondonating capacity of the cationic palladium through back-donation of its d-electrons.Applications of LFER analysis withσPd^(+)to predict the redox behavior of the palladium complex and in a kinetics vs.thermodynamicsmechanistic study of transmetalation added further credence to their applicability to TM systems.

关键词： bond dissociation energy Substituent effects palladium complexes thermodynamics structure–reactivity relationship

Aldol Condensation and Michael Addition of 4,4-Dimethyl- cyclohexane-l,3-dione and Aromatic Aldehydes, Unconventional Substituent effects

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Chinese Journal of Chemistry 2011年第11期29卷 2355-2360页

作者： Kaya, Muharrem Chemistry Department Faculty of Arts and Science Dumlupmar University 43100 Kutahya Turkey

By the cyclization of 4,4-dimethylcyclohexane-1,3-dione with different aromatic aldehydes, the xanthene regio- isomers were obtained. The diversity of xanthene isomers could be determined. The electronic and steric ef... 详细信息

关键词： aldol reaction Michael addition xanthene regioselectivity Substituent effects X-ray diffraction

Substituent effects on the stretching vibration of C=C bridge bond in diphenylpropylenes

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Substituent effects on the stretching vibration of C=C bridg...

Substituent effects on the imine derivatives:A theoretical research from quantum chemistry computation and correlation analysis

中国化学会·第十三届全国物理有机化学学术会议

作者： Linyan Wang Chaotun Cao Chenzhong Cao School of Materials Science and Engineering Hunan University of Science and Technology School of Chemistry and Chemical Engineering Hunan University of Science and Technology

The 38 samples of 1,2’-diphenylpropylenes XArC(Me)=CHArY(XSMBY) were synthesized,and their infrared absorption spectra were recorded.Based on the stretching vibration frequencies v of C=C bridge bond of XSMBYs,an optimality equation quantifying the v values of XSMBYs was obtained(shown as Eq.1).Eq.1 indicates that the Hammett polar constants of X and Y,the excited-state substituent constants of X and Y,and the substituent cross-interaction effect between side-group Me and X are important for the quantitative regression analysis of the vvalues of XSMBYs.The substituent cross-interaction effect between side-group Me and X was expressed by ω,andω=[σ(Me)-σ(X)]=[-0.17-σ(X)].The plot of the v values calculated by Eq.1 versus the experimental ones for XSMBYs was made,as shown in Fig.1.

关键词： Diphenylpropylenes Substituent effects Stretching vibration frequencies substituent cross-interaction effect

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Substituent effects on the imine derivatives:A theoretical r...

Palladium Complexes with N,O-Bidentate Ligands Based on N-Oxide Units from Cyclic Secondary Amines:Synthesis and Catalytic Application in Mizoroki-Heck Reaction

第九届全国计算（机）化学学术会议

作者： Ning-Bew Wong Department of Biology and Chemistry City University of Hong KongKowloonHong gong

The substituent(R=F,OH,OCF3,OCH3,CN,CHO,NH2,NO,CH3,CF3, PH2,SH,SiH3)effects on methanimine(CH2=NH)were investigated using B3LYP and G3 calculations,together with correlation analysis.The results indicate that the charge variation on the C=N bond atoms can be characterized by resonance constants and electronegativities of substituent groups.The FCP(Fractional bond Critical Point) derived from AIM(Atoms in molecules)computation displays a good correlation with the group electronegativity and the AIM charge.The isodesmic reaction study suggests that the electropositive groups would stabilize the N-substituted imines while the highly electronegative substituents along with strong p-donating character would obviously stabilize C-substituted imine derivatives.On the basis of NBO(Nature Bond Orbital)results,the variation of the trans/cis inversion barriers can be attributed to the hyperconjugation of the inverting nitrogen lone pair into the adjacent s(C-R) orbital in the transition state and displays strong dependence upon the electronegativity of substituent groups.

关键词： Substituent effects Imine derivatives Quantumn chemistry computation Correlation analysis

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Chinese Journal of Chemistry 2024年第3期42卷 294-300页

作者： Xuefeng Jia Yanyan Wen Changhui He Xianqiang Huang Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education School of Chemistry and Materials ScienceShanxi Normal UniversityTaiyuanShanxi030032 China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry & Chemical EngineeringLiaocheng UniversityLiaochengShandong252059 China

Palladium-catalyzed Mizoroki-Heck reaction is a powerful and efficient method for construction of Csp2–Csp2 bonds.Herein,four palladium complexes(I—IV)with N,O-bidentate ligands(L1—L4)based on N-oxide units from cyclic secondary amines were easily synthesized and successfully applied in Mizoroki-Heck reaction of aryl bromides with electron-deficient olefins.X-ray diffraction analyses indicated the palladium(II)atom of II took the distorted square planar geometry and was four-coordinated by nitrogen and oxygen atoms from two ligands(L2).Two free chloride ions were presented as counter anions in complex II.But the palladium(II)center of IV was coordinated by nitrogen and oxygen atoms from one ligand(L4)as well as two chlorine atoms,which exhibited the nearly square-planar geometry.The study on catalytic properties of palladium complexes revealed that complex II exhibited high activity superior to the other complexes.The coupling reactions of a series of aryl bromides and olefin derivatives proceeded in the presence of 2—5 mol%palladium complex II,giving the desired products in good to excellent yields.The advantages of this method such as good compatibility of functional groups,high yields,and short reaction times made it more attractive for constructing Csp2–Csp2 bonds in the synthesis of functional molecules and materials.

关键词： Palladium complexes N,O-Bidentate ligands N-Oxide units Mizoroki-Heck reaction Aryl bromide Electron-deficient olefins C—C coupling Homogeneous catalysis Substituent effects

Copper Nitrate-Mediated Selective Bond Cleavage of Alkynes:Diverse Synthesis of Isoxazoles

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Chinese Journal of Chemistry 2023年第23期41卷 3299-3304页

作者： Jianan Liu Kaijing Zhou Shaobo Sun Mingchun Gao Bin Xu Department of Chemistry Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong)Shanghai Engineering Research Center of Organ RepairInnovative Drug Research CenterSchool of MedicineShanghai UniversityShanghai200444 China Qianweichang College Shanghai UniversityShanghai200444 China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032 China

An unprecedented copper nitrate-mediated bond cleavage of alkynes was developed for the modular synthesis of isoxazoles,where either C—S bond or C≡C triple bond was cleaved selectively.substituents attached to the C≡C triple bonds could differentiate the chemical bonds cleavage and reaction pathways disparately.Various transformations of products illustrate promising applications of the given protocols.

关键词： Alkynes Bond cleavage Copper nitrate Cyclization Isoxazoles Molecular diversity N-Heterocycles Substituent effects

A-DA’D-A Type Pentacyclic Small Molecule Acceptors to Exceed 16.5%Efficiency by Heteroatom Effect at the Outer Side Chain

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Chinese Journal of Chemistry 2023年第15期41卷 1815-1822页

作者： Shaofeng Zhu Changzhou Shi Qingya Wei Can Zhu Jie Ren Jianghua Li Lei Meng Yongfang Li Jun Yuan Yingping Zou State Key Laboratory of Powder Metallurgy College of Chemistry and Chemical EngineeringCentral South UniversityChangshaHunan 410083China Beiing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China. MOE Key Laboratory of Macromolecular Synthesis and Functionalization International Research Center for X PolymersDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhouZhejiang 310027China

Comprehensive Summary In this work,we adopt a“heteroatom side-chains”modification strategy to modify the thiophene units in A-DA'D-A(acceptor-donor-acceptor’-donor-acceptor)type pentacyclic SMAs(small molecule acceptors),that is,introducing branched alkyl chain at theβ-position of thiophene instead of straight alkyl chain,and then introducing oxygen atom at the third-position on the basis of branched chain.Two new pentacyclic SMAs(BZ4F-EH and BZ4F-OEH)were synthesized,and the influence of the heteroatom side-chains on photoelectric properties of A-DA'D-A type pentacyclic SMAs was systematically studied.Compared with our previously reported BZ4F(Y26),BZ4F-EH shows slightly blue-shifted absorption,while BZ4F-OEH has obvious red-shifted absorption.As a result,BZ4F-OEH-based binary device achieved a high power conversion efficiency(PCE)of 16.56%with a fill factor(FF)of 79.3%,which is the highest efficiency of pentacyclic SMAs to date.

关键词： Organic solar cells Small molecule acceptors A-DA'D-A type structure Heteroatom side chains Substituent effects

Molecular Uniting Set Identified Characteristic(MUSIC)of Organic Optoelectronic Material

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Chinese Journal of Chemistry 2022年第19期40卷 2356-2370页

作者： Arui Huang Qianqian Li Zhen Li Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Sauvage Center for Molecular SciencesDepartment of ChemistryWuhan UniversityWuhanHubei430072 China Institute of Molecular Aggregation Science Tianjin UniversityTianjin300072 China

Researchers investigated the organic optoelectronic materials and facilitated their development in organic light-emitting diodes(OLEDs),chemo-and biosensors,organic solar cells,data storage,and anticounterfeiting devices.Atoms make up molecules through chemical bonds,and molecular aggregates are formed through weak intermolecular interactions.The opto-electronic performance of these materials depends on not only the properties of the well-designed molecules with specific function groups,but also their aggregate states.The molecular aggregates in the form of nanoparticles can be applied in biological imaging,and films can be applied to photovoltaic and photodeformable devices,in which,the alignment of optoelectronic molecules can be either an ordered crystalline or an amorphous state.Generally,the crystalline materials could be deeply investigated by single crystal/powder X-ray diffraction analysis,which could provide the accurate information about molecular conformations,interactions and packing characteristics.It afforded a convenient way to investigate the possible relationship between molecular aggregates and opto-electronic properties.Among various opto-electronic materials,organic room temperature phosphorescence(RTP)materials exhibit the extremely sensitive luminescence property to molecular aggregates,even the dynamic properties can be detected by the tiny change of molecular aggregates.Thus,we selected the organic RTP emission as the output information of molecular aggregates,and afforded typical examples to find the possible relation between RTP effect and molecular packing.Accordingly,molecular packing can be adjusted by the external force as light,mechanical force,temperature,electric field,and so on,as well as the molecular structures as the building blocks,and the systematic investigation in the dynamic and static aggregation structures is of great value to the design of various optoelectronic materials.This review discusses the relationship among molecular structures,aggregation behaviors and corres

关键词： Aggregation Structure-activity relationships Room temperature phosphorescence Organic opto-electronic material Substituent effects

Positional Electronic effects in Iminopyridine-N-oxide Nickel Catalyzed Ethylene Polymerization

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Chinese Journal of Chemistry 2021年第6期39卷 1683-1689页

作者： Mingjun Chi Ao Chen Wenmin Pang Chen Tan Changle Chen CAS Key Laboratory of Soft Matter Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefeiAnhui 230026China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefeiAnhui 230026China

A series of dibenzhydryl-based iminopyridine-N-oxide ligands bearing a range of electron-donating or-withdrawing substituents(OMe,H;and NO_(2))and corresponding nickel pre-catalysts are prepared and characterized.The substituents are installed at different positions on the ligand structure,including 4-position of the pyridine-N-oxide moiety(position X)and 4-position of the aniline moiety(position Y).These nickel pre-catalysts are highly active in ethylene polymerization with the addition of very little amount of aluminum cocatalysts,leading to the formation of polyethylenes with molecular weights of well above one million.Electron-donating substituents make the catalysts sensitive to polymerization temperature.In contrast,the catalysts bearing electron-withdrawing NO_(2) substituents show relatively steady performances at different temperatures.Most importantly,we demonstrate that different substituents and different positions both play important roles in determining the properties of nickel catalysts.This provides an alternative strategy for the future design of high-performance polymerization catalyst.

关键词： Ethylene Polymerization Nickel lminopyridine-N-oxide Substituent effects

New Quinoxaline-Based Blue Emitters: Molecular Structures, Aggregation-Induced Enhanced Emission Characteristics and OLED Application

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Chinese Journal of Chemistry 2021年第8期39卷 2154-2162页

作者： Xiaoyu Mao Fuli Xie Xiaohui Wang Qingsong Wang Zhipeng Qiu Mark R.J.Elsegood Jie Bai Xing Feng Carl Redshaw Yanping Huo Jian-Yong Hu Qing Chen Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter School of Material and EnergyGuangdong University of TechnologyGuangzhouGuangdong 510006China Shaanxi Key Laboratory for Advanced Energy Devices School of Materials Science and EngineeringShaanxi Normal UniversityXi'anShaanxi 710119China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhouGuangdong 510006China Chemistry Department Loughborough UniversityLoughboroughLE113TUUK Department of Chemistry University of HullCottingham RoadHullYorkshire HU67RXUK Chinese Research Academy of Environmental Sciences No.8DayangfangBeiyuanBeijingChina

Three new deep blue light emitters,bearing quinoxaline with different substituents(biphenyl/pyrene)at the 1-or 2-position,were synthesized by a Pd-catalysed coupling reaction in high yields,and were fully characterize... 详细信息

关键词： Quinoxaline Pyrene Aggregation-induced emission Solid-state structures Substituent effects