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Spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation

National Science Review 2024年第2期11卷 155-167页

作者： Peng He Meng-Yang Hu Jin-Hong Li Tian-Zhang Qiao Yi-Lin Lu Shou-Fei Zhu Frontiers Science Center for New organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the Earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. Deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

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Exfoliation,functionalization and antibacterial activity of transition metal dichalcogenides

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Tungsten 2024年第1期6卷 1-16页

作者： Avijit Mondal Mrinmoy De Department of organic chemistry Indian Institute of ScienceBengaluru 560012India

Due to the growing resistance of available drugs to bacterial infection and the slow development of antibiotics,there is a continuous need to design and develop new antibacterial *** interest to develop transition metal dichalcogenides(TMDs)based antibacterial agents has significantly increased in recent *** research interest is driven by their interesting properties such as metallic and semiconducting nature of different phases,electronic confinement,large surface to volume ratio,the possibility of surface functionalization,and their potential application as a material in biomedical *** synthetic strategies have been developed to synthesize monolayered TMDs and their functionalization with different bioactive *** have given a lot of effort to establish the structure-activity correlation between different TMDs and their antibacterial ***,we have reviewed various exfoliation strategies for TMDs,different methods for their functionalization,and the antibacterial activity of different TMDs.

关键词： Transition metal dichalcogenides(TMD) Functionalization Antibacterial activity Antibacterial mechanism

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The chlorine evolution reaction promoted by organocatalysts with amide functional groups

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Science China chemistry 2024年第3期67卷 749-750页

作者： Lan Zhao Liang-Nian He State Key Laboratory and institute of Elemento-organic chemistry College of ChemistryNankai UniversityTianjin 300071China

Since the nineteenth century, the chlor-alkali process entails the electrochemical oxidation of sodium chloride solutions to Cl_(2) by the chlorine evolution reaction(CER) and the simultaneous production of sodium hyd... 详细信息

关键词： chlorine hydroxide promoted

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Copper-catalyzed asymmetric dearomatizing amination of 2-naphthols:Csp^(2)–N coupling via 1,3-reductive elimination

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Science China chemistry 2024年第8期67卷 2694-2700页

作者： Aying Yihuo Maoping Pu Zheng Tan Jibang Liao Jiuqi Tan Qi-Lin Zhou Xiaohua Liu Xiaoming Feng Key Laboratory of Green chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064China Key Laboratory and institute of Elemento-organic chemistry College of Chemistry Frontiers Science Centerfor New Organic MatterNankai UniversityTianjin300071China

An efficient catalytic asymmetric dearomatizing amination of 2-naphthols and phenols catalyzed by N,N′-dioxide-copper(I)complex as a chiral catalyst was presented.A variety of optically activeβ-naphthalenone compounds with a nitrogen-containing quaternary carbon stereocenter were obtained with high yield and enantioselectivity under mild reaction *** studies indicated that this Csp^(2)–N dearomatizing coupling proceeds via 1,3-reductive elimination of phenolate-Cu~Ⅲ-amino intermediate in five-membered ring transition *** origin of enantioselectivity has also been elucidated based on density functional theory calculations.

关键词： asymmetric catalysis amination dearomatization copper catalysis coupling reaction

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Dielectric Constant Calculation of Poly(vinylidene fluoride)Based on Finite Field and Density Functional Theory

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Chinese Journal of Polymer Science 2024年第5期42卷 655-662,I0009页

作者： Yong-Zhi Lin Lu-Kun Feng Ya-Dong Li Chao-Fan Chang Cai-Zhen Zhu Ming-Liang Wang Jian Xu College of chemistry and Environmental Engineering Shenzhen UniversityShenzhen518055China Chengdu institute of organic chemistry Chinese Academy of SciencesChengdu610041China

In this study,we proposed a novel method that integrates density functional theory(DFT)with the finite field method to accurately estimate the polarizability and dielectric constant of *** approach effectively accounts for the influence of electronic and geometric conformation changed on the dielectric *** validated our method using polyethylene(PE)and polytetrafluoroethylene(PTFE)as benchmark materials,and found that it reliably predicted their dielectric ***,we explored the impact of conformation variations in poly(vinylidene fluoride)(PVDF)on its dielectric constant and *** resulting dielectric constants ofα-andγ-PVDF(3.0)showed excellent agreement with crystalline PVDF in *** findings illuminate the relationship between PVDF’s structural properties and its electrical behavior,offering valuable insights for material design and applications.

关键词： Dielectric constant PVDF Finite field DFT

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Asymmetric side-chain engineering of organic semiconductor for ultrasensitive gas sensing

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Chinese Chemical Letters 2024年第3期35卷 428-433页

作者： Xiaoying Ma Xiaojuan Dai Lanyi Xiang Jiajun Chang Danfeng Zhi Haozhen Zhao Zhenjie Ni Ye Zou Xike Gao Fengjiao Zhang School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Laboratory of organic Solids Institute of ChemistryChinese Academy of SciencesBeijing 100190China Key Laboratory of Synthetic and Self-Assembly chemistry for organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Binzhou institute of Technology Binzhou 256606China

Molecular structure of organic semiconductor plays a critical role in determining the performance and functionality of organic electronic devices,by optimizing the electrical,optical and physicochemical *** alkyl chains are fundamental units in tailering the solubility and assemblability,among which the asymmetric properties have been reported as key element for controlling the packing motifs and intrinsic charge ***,we expanded the scope of molecular asymmetry dependent sensing features based on a new series of naphthalene diimides(NDI)-based derivatives substituted with a same branching alkyl chain but various linear-shaped alkyl chains(Cn-).A clear molecular stacking change,from head-to-head bilayer to head-to-tail monolayer packing model,is observed based on the features of anisotropic molecular interactions with the change in the chain *** importantly,a unique LUMO level shift of 0.17 eV is validated for NDI-PhC4,providing a record sensitivity up to 150%to 0.01 ppb ammonia,due to the desired molecular reactivity and device amplification *** results indicate that asymmetric side-chain engineering opens a route for breath healthcare.

关键词： organic thin film transistor Asymmetric side chain Gas sensing Molecular stacking Energy level manipulating

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Cobalt(Ⅲ)hydride HAT mediated enantioselective intramolecular hydroamination access to chiral pyrrolidines

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Science China chemistry 2024年第6期67卷 2002-2008页

作者： Qi Meng Tao Qin Huanran Miao Ge Zhang Qian Zhang Jilin Province Key Laboratory of organic Functional Molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun130024China State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Enantioenriched pyrrolidines and derivatives are ubiquitous substructures in compounds of importance to medicinal and biological ***,we report an efficient cobalt-catalyzed intramolecular asymmetric hydroamination reaction that produces chiral pyrrolidines with good to excellent yield and *** with previously reported radicalinvolved methodologies for enantioenriched pyrrolidines,these conditions feature two elegant versatilities,enabling(1)the use of cobalt-catalyzed hydrogen atom transfer(HAT)to generate organocobalt intermediates that bring radical reaction to organometallic chemistry,and(2)enantioselective intramolecular C-N bond forging through an S_(N)2-like displacement involving dynamic kinetic resolution(DKR).This approach provides a new alternative and efficient methodology for enantioselective radical-involved C-N bond construction that can be used in the synthesis of both chiral pyrrolidines and homologous nitrogen heterocycles.

关键词： asymmetric catalysis radical hydroamination cobalt catalysis hydrogen atom transfer

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Polyethylene to gasoline via a self-supplied hydrogen strategy

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Science China chemistry 2024年第10期67卷 3187-3188页

作者： Yong Tang State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Polyethylenes(PEs)are one of the most widely used plastics in almost every aspect of modern life and are produced on a huge scale(a market volume of 110.13 million metric tons worldwide in 2022)[1].A large portion of the PEs are used once and discarded as waste,which caused severe problems such as plastic pollution as well as a waste of the fossoil resource.

关键词： pollution plastics strategy

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High-speed flexible near-infrared organic photodiode for optical communication

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National Science Review 2024年第03期11卷 227-238页

作者： Yu Zhu Hongbin Chen Ruiman Han Hao Qin Zhaoyang Yao Hang Liu Yanfeng Ma Xiangjian Wan Guanghui Li Yongsheng Chen The centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer Materials Institute of Polymer ChemistryTianjin Key Laboratory of Functional Polymer Materials College of Chemistry and Renewable Energy Conversion and Storage Center(RECAST) Nankai University State Key Laboratory of Elemento-organic chemistry Nankai University

Optical communication is a particularly compelling technology for tackling the speed and capacity bottlenecks in data communication in modern society. Currently, the silicon photodetector plays a dominant role in high-speed optical communication across the visible-near-infrared spectrum. However, its intrinsic rigid structure, high working bias and low responsivity essentially limit its application in next-generation flexible optoelectronic devices. Herein, we report a narrow-bandgap non-fullerene acceptor（NFA） with a remarkable π-extension in the direction of both central and end units（CH17） with respect to the Y6 series, which demonstrates a more effective and compact 3D molecular packing, leading to lower trap states and energetic disorders in the photoactive film. Consequently, the optimized solution-processed organic photodetector（OPD） with CH17 exhibits a remarkable response time of 91 ns（λ = 880 nm） due to the high charge mobility and low parasitic capacitance, exceeding the values of most commercial Si photodiodes and all NFA-based OPDs operating in self-powered mode. More significantly, the flexible OPD exhibits negligible performance attenuation（<1%） after bending for 500 cycles, and maintains 96% of its initial performance even after 550 h of indoor exposure. Furthermore, the high-speed OPD demonstrates a high data transmission rate of 80 MHz with a bit error rate of 3.5 × 10-4, meaning it has great potential in next-generation high-speed flexible optical communication systems.

关键词： flexible organic photodetector high-speed NIR organic photodetector optical communication light fidelity narrow-bandgap non-fullerene acceptors

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Iridium-Catalyzed Asymmetric Hydrogenation of Dialkyl Imines

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CCS chemistry 2024年第4期6卷 905-911页

作者： Zheng Wang Xin-Yi Yang Yue Xu Qi-Lin Zhou State Key Laboratory and institute of Elemento-organic chemistry College of ChemistryFrontiers Science Center for New Organic MatterNankai UniversityTianjin 300071

Asymmetric hydrogenation of dialkyl imines to chiral amines is difficult because the two alkyls of imines are so similar in spatial and electronic structure that chiral catalysts are difficult to distinguish between *** this study,we described an asymmetric hydrogenation of dialkyl imines by a chiral iridium catalyst containing spiro phosphine-amine-phosphine *** precisely adjusting the chiral pocket of catalyst,a highly efficient catalyst was *** this catalyst,a variety of dialkyl imines were hydrogenated to chiral amines with high yield and enantioselectivity.

关键词： spiro PNP ligand iridium catalyst enantioselective hydrogenation dialkyl imines chiral amines

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