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Rhodium-Catalyzed Asymmetric Transfer Hydrogenation of Heterocyclic Diaryl Ketones:Facile Access to Key Intermediate of Baloxavir

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Chinese Journal of Chemistry 2024年第1期42卷 43-47页

作者： Li Wang Renwei Xiao Jingyuan Song Long-Sheng Zheng Qiwei Lang Gen-Qiang Chen Xumu Zhang shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis Department of Chemistryand Medi-PingshanSouthern University of Science and TechnologyShenzhenGuangdong 518000China Academy for Advanced Interdisciplinary Studies Southern Universityof Science and TechnologyShenzhenGuangdong 518000China Chemistry and Chemical Engineering Guangdong Laboratory ShantouGuangdong 515031China

Transition metal-catalyzed asymmetric transfer hydrogenation has been proven to be a powerful approach for the synthesis of chiral ***,a highly efficient and enantioselective transfer hydrogenation of dibenzoheptaheterocyclic ketones catalyzed by an arene-tethered TsDPEN-based Rh(ll)catalyst has been successfully developed,and a variety of dibenzoheptaheterocyclic ketones were reduced by a 1/1 mixture of formic acid and DBU(1,8-diazabicyclo[5.4.0]undec-7-ene)with high yields and *** this method,the asymmetric reduction of 7,8-difluorodibenzo[b,e]thiepin-11(6H)-one has been realized,providing the key intermediate of baloxavir marboxil with>99% yield and>99% ee at a substrate/catalyst molar ratio of 1000.

关键词： Asymmetric transfer hydrogenation Baloxavir Chiral alcohol Enantioselectivity Heterocyclic diaryl ketone Rhodium(Ⅱ)

Association analysis of an anti-obesity mechanism and key ripened Pu-erh tea bioactive components by mimicking human general tea drinking

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Food science and Human Wellness 2024年

作者： Junyu Liu Zhengyang Song Haihong Chen Wen Zeng Guirong Han Wei Li Bing Xu Yuan Lu Canyang Zhang Zhenglian Xue Bin Lü Chong Zhang Song Yang Yi Wang Xinhui Xing Institute of Biomedical Health technology and Engineering Shenzhen Bay Laboratory MOE Key Laboratory for Industrial Biocatalysis Centre for Synthetic and Systems Biology Department of Chemical Engineering Tsinghua University shenzhen International Graduate School Tsinghua University Shandong Province Key Laboratory of Applied Mycology Qingdao International Center on Microbes Utilizing Biogas School of Life sciences Qingdao Agricultural University Anhui University of technology Yunnan Shujian Tea Co. Ltd.

Pu-erh tea， a traditional Chinese beverage， performs an anti-obesity function， but the correlation between its components and efficacy remains unknown. Here， we screened two Pu-erh teas with significant anti-obesity efficacies from 11 teas. In vitro experiments revealed that lipid accumulation in L02 cells and lipid synthesis in 3T3-L1 cells were significantly better inhibited by Tea-B than Tea-A. Further in vivo experiments using model mice revealed that the differences in chemical components generated two pathways in the anti-obesity efficacy and mechanism of Pu-erh teas. Tea-A changes the histomorphology of brown adipose tissue (BAT) and increases the abundance of Coriobacteriaceae＿UCG＿002 and cyclic AMP in guts through high chemical contents of cyclopentasiloxane， decamethyl， tridecane and 1，2，3-trimethoxybenzene， eventually increasing BAT activation and fat browning gene expression; the high content of hexadecane and 1，2-dimethoxy-benzene in Tea-B reduces white adipose tissue (WAT) accumulation and the process of fatty liver， increases the abundance of Odoribacter and sphinganine 1-phosphate， inhibits the expression of lipid synthesis and transport genes. These mechanistic findings on the association of the representative bioactive components in Pu-erh teas with the anti-obesity phenotypes， gut microbes， gut metabolite structure and anti-obesity pathways， which were obtained for the first time， provide foundations for developing functional Pu-erh tea.

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Construction of a Metallacyclopentadiene Ring through the Attack of Carbanions to M≡C Bond Followed by C—H Activation

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Chinese Journal of Chemistry 2024年第3期42卷 235-242页

作者： Chun Tang Shengjie Zhang Zhengyu Lu Qian Li Ming Luo Dafa Chen Haiping Xia State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringCollaborative Innovation Center of Chemistry for Energy MaterialsXiamen UniversityXiamenFujian361005 China shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong518055 China

Metallacyclopentadienes are important metallacycles and regarded as intermediates in many reactions,therefore,new methods to achieve them are *** this study,a formal[3+2]method,through the reactions of an osmapentalyne with benzyl carbanions,was *** reactions underwent a nucleophilic attack of carbanions to the Os≡C bond,followed by C—H activation to form the five-membered osmacyclopentadiene *** of the reactions were carried out at room temperature,the substituents on the aromatic rings of benzyl carbanions are diverse,and the resulting products contain an Os—H bond,representing a novel type of 10C-carbolong *** work provides a new convenient route to construct metallacyclopentadienes,which is expected to further promote the development of such a type of substances.

关键词： Metallacyclopentadiene Carbolong chemistry Osmium C–H activation Nucleophilic addition

MOF-mediated synthesis of novel PtFeCoNiMn high-entropy nanoalloy as bifunctional oxygen electrocatalysts for zinc-air battery

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Nano Research 2024年第6期17卷 5288-5297页

作者： Mingkuan Xie Xin Xiao Duojie Wu Cheng Zhen Chunsheng Wu Wenjuan Wang Hao Nian Fayan Li Meng Danny Gu Qiang Xu shenzhen Key Laboratory of Micro/Nano-Porous Functional Materials(SKLPM) Shenzhen 518055China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China Department of Materials science and Engineering Southern University of Science and TechnologyShenzhen 518055China SUSTech-Kyoto University Advanced Energy Materials Joint innovation Laboratory(SKAEM-JIL) Shenzhen 518055China Key University Laboratory of Highly Efficient Utilization of Solar Energy and Sustainable Development of Guangdong Southern University of Science and TechnologyShenzhen 518055China Eastern Institute for Advanced Study Eastern Institute of TechnologyNingbo 315200China

High-entropy alloy(HEA)-based materials are expected to be promising oxygen electrocatalysts due to their exceptional *** electronic structure regulation of HEAs plays a pivotal role in enhancing their elctrocatalytic ***,PtFeCoNiMn nanoparticles(NPs)with subtle lattice distortions are constructed on metal-organic framework-derived nitrogen-doped carbon by an ultra-rapid Joule heating *** to the modulated electronic structure and the inherent cocktail effect of HEAs,the as-synthesized PtFeCoNiMn/NC exhibits superior bifunctional electrocatalytic performance with a positive half-wave potential of 0.863 V *** hydrogen electrode(RHE)for oxygen reduction reaction and a low overpotential of 357 mV at 10 mA·cm^(-2)for oxygen evolution *** assembled quasi-solid-state zinc-air battery using PtFeCoNiMn/NC as air electrode shows a high peak power density of 192.16 mW·cm^(-2),low charge−discharge voltage gap,and excellent durability over 500 cycles at 5 mA·cm^(-2).This work demonstrates an effective route for rational design of bifunctional nanostructured HEA electrocatalysts with favorable electronic structures,and opens up a fascinating directions for energy storage and conversion,and beyond.

关键词： oxygen reduction reaction oxygen evolution reaction high-entropy nano-alloy zinc-air battery

Laser-assisted grinding of RB-SiC composites:Laser ablation behavior and mechanism

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Chinese Journal of Aeronautics 2024年第1期37卷 362-376页

作者： Zhigang DONG Wenchao SUN Xintong CAI Feng YANG Yan BAO Renke KANG Dongjiang WU Guangyi MA Fangyong NIU Key Laboratory for Precision and Non-traditional Machining technology of the Ministry of Education School of Mechanical EngineeringDalian University of TechnologyDalian 116024China

Laser ablation is an important process during Laser-Assisted Grinding(LAG)of hard and brittle *** realize controllable material removal during laser ablation of RB-SiC composites,ablation experiments under different Laser Energy Density(LAED)and LAG experiments are *** rules and mechanism of physical phase,ablation morphology and crack characteristics caused by laser irradiation are *** forces of LAG and Conventional Grinding(CG)are *** results show that ablation surface changes from slight oxidation to obvious material removal with LAED increasing,and ablation depth increases *** ablation products change from submicron SiO_(2)particles to nanoscale particles and *** LAED promotes SiC decomposition and sublimation,which leads to the increase of C *** SiC phase forms corrugated shape in recast layer and columnar shape in Heat Affected Zone(HAZ)at 56 J/mm^(2).The cold and heat cycle leads to formation of fishbone *** ablation specimen under 30 J/mm^(2),the grinding force can be reduced by a maximum of 39%and brittle damage region is *** material removal and microcrack generated will significantly reduce the hardness and improve machinability,which can promote grinding efficiency.

关键词： RB-SiC Laser Ceramic Composites Grinding

Electron-transporting boron-doped polycyclic aromatic hydrocarbons:Facile synthesis and heteroatom doping positions-modulated optoelectronic properties

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Chinese Chemical Letters 2024年第4期35卷 447-451页

作者： Tingting Huang Zhuanlong Ding Hao Liu Ping-An Chen Longfeng Zhao Yuanyuan Hu Yifan Yao Kun Yang Zebing Zeng Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China shenzhen Research Institute of Hunan University Shenzhen 518000China Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education and Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices School of Physics and Electronics Hunan UniversityChangsha 410082China

While heteroatom doping serves as a powerful strategy for devising novel polycyclic aromatic hydrocarbons(PAHs), the further fine-tuning of optoelectronic properties via the precisely altering of doping patterns remains a challenge. Herein, by changing the doping positions of heteroatoms in a diindenopyrene skeleton, we report two isomeric boron, sulfur-embedded PAHs, named Anti-B_(2)S_(2) and Syn-B_(2)S_(2), as electron transporting semiconductors. Detailed structure-property relationship studies revealed that the varied heteroatom positions not only change their physicochemical properties, but also largely affect their solid-state packing modes and Lewis base-triggered photophysical responses. With their low-lying frontier molecular orbital levels, n-type characteristics with electron mobilities up to 1.5 × 10^(-3)cm^(2)V^(-1)s^(-1)were achieved in solution-processed organic field-effect transistors. Our work revealed the critical role of controlling heteroatom doping patterns for designing advanced PAHs.

关键词： Polycyclic aromatic hydrocarbon Optoelectronic properties Heteroatom doping n-Type organic semiconductors Structure–property relationship

Nitrogen incorporated oxygen vacancy enriched MnCo_(2)O_(x)/BiVO_(4) photoanodes for efficient and stable photoelectrochemical water splitting

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Nano Research 2024年第3期17卷 1140-1150页

作者： Liangcheng Xu Yingjuan Zhang Boyan Liu Xin Wang Gangqiang Zhu Lianzhou Wang Songcan Wang Wei Huang Frontiers science Center for Flexible Electronics Xi’an Institute of Flexible Electronics(IFE)Northwestern Polytechnical University127 West Youyi RoadXi’an 710072China School of Physics and Information technology Shaanxi Normal UniversityXi’an 710062China Nanomaterials Centre Australian Institute for Bioengineering and Nanotechnology and School of Chemical EngineeringThe University of QueenslandBrisbaneQueensland 4072Australia Research&Development Institute of Northwestern Polytechnical University in shenzhen Sanhang Science&Technology BuildingNo.45thGaoxin South 9th RoadNanshan DistrictShenzhen 518063China

Oxygen vacancies in oxygen evolution cocatalysts(OECs)can significantly improve the photoelectrochemical(PEC)water splitting performance of ***,OECs with abundant oxygen vacancies have a poor stability when exposing to the highly-oxidizing photogenerated ***,we partly fill oxygen vacancies in a MnCo_(2)O_(x) OEC with N atoms by a combined electrodeposition and sol-gel method,which dramatically improves both photocurrent density and stability of a BiVO_(4) *** optimized N filled oxygen vacancy-rich MnCo_(2)O_(x)/BiVO_(4) photoanode(3 at.%of N)exhibits an outstanding photocurrent density of 6.5 mA·cm^(-2) at 1.23 VRHE under AM 1.5 G illumination(100 mW·cm^(-2)),and an excellent stability of over 150 *** characterizations and theoretical calculations demonstrate that N atoms stabilize the defect structure and modulate the surface electron distribution,which significantly enhances the stability and further increases the photocurrent ***,other heteroatoms such as carbon,phosphorus,and sulfur are confirmed to have similar effects on improving PEC water splitting performance of photoanodes.

关键词： water splitting oxygen evolution bismuth vanadate(BiVO_(4)) filling oxygen vacancies cocatalysts

Visible and selective gel assembly via covalent click chemistry

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SmartMat 2024年第2期5卷 137-144页

作者： Yinglin Zheng Zhihai Ke School of science and Engineering The Chinese University of Hong KongShenzhenChina

This study marks the birth of visible and selective click covalent *** is achieved by amplifying orthogonal alkyne−azide click chemistry through interfacial multisite interactions between azide/alkyne functionalized polymer *** assembly of hydrogels via host−guest chemistry or noncovalent interactions such as electrostatic interactions has been *** macroscopic supramolecular assembly,here we report visible and selective“click”covalent assembly of hydrogels at the ***-like hydrogels modified with alkyne and azide groups,respectively,can click together via the formation of covalent *** concentration-dependent assembly and selective covalent assembly have been ***,macroscopic gel assembly clearly elucidates click preferences and component selectivity not observed in the solution reactions of competing monomers.

关键词： click chemistry hydrogel selective covalent assembly

Catalytic enantioselective N-silylation of sulfoximine

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Chinese Chemical Letters 2024年第4期35卷 352-356页

作者： Xingfen Huang Jiefeng Zhu Chuan He shenzhen Grubbs Institute and Department of Chemistry Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China Key Laboratory of Organosilicon Chemistry and Material technology of Ministry of Education Hangzhou Normal UniversityHangzhou 311121China

A rhodium/diphosphine-catalyzed asymmetric cross-dehydrogenative coupling between sulfoximines and dihydrosilanes has been achieved. This is the first report on the enantioselective N-silylation of sulfoximines. The protocol gives access to a variety of Si-stereogenic N-silylated sulfoximines in decent yield(up to 99%) with excellent stereoselectivity(up to 99%), featuring high atom economy, and a cleaner manner with H2as the sole byproduct. The obtained bis-Si-stereogenic monohydrosilane product can be further converted into the corresponding chiral polymer with pendant sulfoximine groups.

关键词： N-Silylation of sulfoximine Chiral silylamine Si-stereogenic silanes Si-CADC Asymmetric catalysis