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Towards climate neutrality for household energy consumption

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National Science Review 2022年第7期9卷 12-12页

作者： Ortwin Renn institute for advanced Sustainability studies

The Paris Agreement,reinforced by the 2021 conference in Glasgow,obliges all nations that have signed the agreements to reduce the release of greenhouse gases to zero within the next few decades.China’ s central government has made two signature commitments on climate,pledging that the country’ s carbon dioxide emissions will peak before 2030,and the country will achieve carbon neutrality before 2060,

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Reversing Conventional Site-Selectivity:Electrochemically Driven C(sp^(2))-H/C(sp^(3))-H Coupling with H_(2)Evolution

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CCS Chemistry 2023年第5期5卷 1086-1095页

作者： Xuelian Zheng Pan Peng Cheng Huang Qingquan Lu The Institute for Advanced Studies Wuhan UniversityWuhan 430072

Sustainable and site-selective C–H functionalization is still a challenge because of the comparable properties of bonds of the same type.Here,an electrochemical C(sp^(2))–H/C(sp^(3))–H coupling with aryl iodides is reported for the first time.The C(sp^(2))–H bond outperformed the much weaker C(sp^(2))–I bond participating in C(sp^(2))–H/C(sp^(3))–H coupling.This protocol features mild reaction conditions,good functional group tolerance,and scalability.Crosscoupling products with C–I bonds are versatile moieties for further synthetic manipulation,that can undergo Suzuki,Sonogashira,Ullmann-Ma,Catellani,Heck reactions,and so on to introduce new functional groups into target molecules with good yields.Mechanistic investigations showed that the site selectivity of the reaction is enabled by an iodineassisted[3,3]-sigmatropic rearrangement,and the interaction of hypervalent iodine generated in situ with an enolate is the rate-determining step.

关键词： electrosynthesis electrooxidation C–H functionalization oxidative coupling alkylation

Integrating aryl chlorides into nickel-catalyzed 1,1-difunctionalization of alkenes

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Chinese Chemical Letters 2022年第12期33卷 5096-5100页

作者： Caocao Sun Guoyin Yin The Institute for Advanced Studies Wuhan UniversityWuhan 430072China

Difunctionalization of alkenes have developed into an important type of reactions for rapidly and efficiently assemble complex molecules.While extensive advancements have been achieved by the assistance of transition metal catalysis,the employment of cheap,abundant aryl chlorides as coupling partner is still a challenging task in this field.Herein,we report our first achievement in 1,1-difunctionalization of alkenes with aryl chlorides as coupling partners.The success is predominantly ascribed to the judicious selection of 1,2-diamine ligand.This study provides an efficient protocol for the synthesis of secondary benzyl boronates from easily accessible feedstock chemicals.Furthermore,the distinguished features of this method include excellent 1,1-regio-and chemoselectivity,good functional group tolerance and easily-operational catalytic reaction conditions.

关键词： Aryl chlorides Difunctionalization of alkenes Regioselectivity Nickel catalysis

Plant polyploidy and evolution

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Journal of Integrative Plant Biology 2019年第1期61卷 4-6页

作者： Gai Huang Yu-Xian Zhu institute for advanced studies Wuhan University

Polyploidy refers to two or more complete sets of chromosomes that are combined within a nucleus,and includes both autopolyploidy and allopolyploidy(Otto 2007).Polyploidy is a recurring theme in the evolutionary history of plants and it has been considered an important mechanism for speciation and also for adaptability to changing environments(Shimizu-Inatsugi et al.2017).In nature,about one-third of flowering plants are polyploids,and a great majority of them are allopolyploids.There are many cultivated allopolyploid species,such as cotton,Brassica and potato,the possible evolutionary history of which can be inferred with high certainty.

关键词： Polyploidy history

Assessment of groundwater potential using multi-criteria decision analysis and geoelectrical surveying

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Geo-Spatial Information Science 2022年第4期25卷 600-618页

作者： Marzieh Shabani Zohreh Masoumi Abolfazl Rezaei Department of Earth Sciences Institute for Advanced Studies in Basic Sciences(IASBS)ZanjanIran Center for Research in Climate Change and Global Warming(CRCC) Institute for Advanced Studies in Basic Sciences(IASBS)ZanjanIran

A precise map of the dispersion of the groundwater potential across each watershed can help decision-makers to exert optimal water management in each region.In this research,the potential of groundwater resources in both the Zanjanrood Catchment and the Tarom Region,located in the northwest of Iran,has been studied.Seven effective criteria including slope,land-use,drainage density,spring density,lithology,lineament density,and rainfall are considered.Criteria were first weighted using the Analytical Hierarchical Process(AHP)method and then overlaid by the Technique for Order Preferences by Similarity to Ideal(TOPSIS)model.Finally,the spatial zoning map of groundwater potential was obtained in four categories.A sensitivity analysis was performed to determine the influence of each criterion on the obtained map.The model was verified using both the spatial distribution of the high-discharged production wells and the geophysical-based geoelectric field surveys.The results indicate that the high-discharged wells(>40 l/s)in both regions are dispersed predominantly in the very good zone and,in several cases,in the good zone.Besides,the results from the two-dimensional models of resistivity and induced polarization of geoelectrical field survey are inappropriate agreement with those from the TOPSIS method.Notably,there is no suitable potential zone of groundwater in the surrounding highlands to be used in the future for drinking purposes since the highlands water supply is a strategic supply for drinking.The strategies employed in this study,the results of GIS modeling,and the geoelectrical analysis can be considered for sustainable development of similar arid and semi-arid areas since groundwater is considered as the main supplier of water in such regions.

关键词： Spatial Information System(GIS) Remote Sensing(RS) groundwater potential TOPSIS geoelectrical field survey sustainable development

Precise electro-reduction of alkyl halides for radical defluorinative alkylation

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Science China Chemistry 2022年第4期65卷 762-770页

作者： Xingxiu Yan Shengchun Wang Zhao Liu Yujie Luo Pengjie Wang Wenyan Shi Xiaotian Qi Zhiliang Huang Aiwen Lei institute for advanced studies(IAS)and College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China

Reported here is a precise electro-reduction strategy for radical defluorinative alkylation towards the synthesis of gem-difluoroalkenes from α-trifluoromethylstyrenes. According to the redox-potential difference of the radical precursors, direct or indirect electrolysis is respectively adopted to realize the precise reduction. An easy-to-handle, catalyst-and metal-free condition is developed for the reduction of alkyl radical precursors that are generally easier to be reduced than α-trifluoromethylstyrenes,while a novel electro-Ni-catalytic system is established for the electro-reduction of alkyl bromides or chlorides towards the electrochemical synthesis of gem-difluoroalkenes. The merit of this protocol is exhibited by its mild conditions, wide substrate scope, and scalable preparation. Mechanistic studies and DFT calculations proved that the coordination of α-trifluoromethylstyrenes to Ni-catalyst prevents the direct reduction of the alkene and, in turn, promotes the activation of alkyl bromide through halogen atom transfer mechanism.

关键词： electro-reductive cross-coupling gem-difluoroalkenes radical defluorinative alkylation electro/nickel catalysis C-C bonds formation

Diversity-Oriented Synthesis of Flavones and Isoflavones via Palladium/Norbornene Cooperative Catalysis

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Chinese Journal of Chemistry 2022年第6期40卷 675-680页

作者： Yuanyuan Ma Qianwen Gao Lan Zhou Shanshan Liu Hong-Gang Cheng Qianghui Zhou institute for advanced studies Wuhan UniversityWuhanHubei 430072ChinaSauvage Center for Molecular SciencesCollege of Chemistry and Molecular Sciences at Wuhan UniversityWuhanHubei 430072China institute for advanced studies Wuhan UniversityWuhanHubei 430072China

Flavones and isoflavones are recognized as privileged heterocyclic scaffolds for the preparation of bioactive compounds.Efficient methods to access these heterocycles are in urgent need.Herein,we report diversity-oriented synthesis of flavones and isoflavones from 3-iodochromones via palladium/norbornene cooperative catalysis.The success of this research relies on the use of a unique bridge-head ester modified norbornene derivative as the mediator.Salient features of this include readily available starting materi-als regarding 3-iodochromones,ortho-C-H arylating and alkylating reagents and ipso-terminating reagents,broad substrate scope,good chemoselectivity,good step-economy and scalability.A large number of structurally diversified flavones,isoflavones and 2,3-diarylated chromones can be quickly prepared in a predictable manner.As showcased by the efficient formal synthesis of um-bralisib,this chemistry can be treated as another valuable addition to the toolbox of medicinal chemists.

关键词： Diversity-oriented synthesis Oxygen heterocycle Palladium Norbornene C-H activation

Electrooxidation-Induced C(sp^(3))-H/C(sp^(2))-H Radical-Radical Cross-Coupling between Xanthanes and Electron-Rich Arenes

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Chinese Journal of Chemistry 2022年第12期40卷 1422-1428页

作者： Yuwei Liang Linbin Niu Xing-An Liang Shengchun Wang Pengjie Wang Aiwen Lei College of Chemistry and Molecular Sciences Institute for Advanced Studies(IAS)Wuhan UniversityWuhanHubei 430072China

The arylation of C(sp^(3))-H bonds has been a priority research topic in organic synthesis.Minsici reactions have been the powerful methods for C(sp^(3))-C(sp^(2))bonds formation.Despite its mature development,the scopes of arenes are usually suitable for elec-tron-deficient heterocyclic compounds,rather than electron-rich arenes.Herein,we report an electrooxidation-induced alkylation of electron-rich arenes with H_(2) evolution under exogenous oxidant-free conditions,avoiding the utilization of metal catalysts.This pro-tocol is well performed with various electron-rich aniline derivatives and nitrogen-containing heterocyclic compounds.We anticipate that this electro-oxidative C(sp^(3))-H arylation represents an important expansion for the classic arenes alkylation,thereby proving an attractive strategy for the developments of radical cross-coupling chemistry.

关键词： Electrochemistry C-H activation C-C coupling C(sp^(2))-H alkylation Electron-rich arenes

Multi objective prediction and optimization of control parameters in the milling of aluminium hybrid metal matrix composites using ANN and Taguchi-grey relational analysis

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Defence Technology（防务技术） 2019年第4期15卷 545-556页

作者： S.Ajith Arul Daniel R.Pugazhenthi R.Kumar S.Vijayananth Department of Mechanical Engineering Vels Institute of ScienceTechnology and Advanced Studies

This study aims to optimize the input parameters such as mass fraction and particle size of SiC along with depth of cut,feed and cutting speed in the milling of Al5059/SiC/MoS2.The hybrid metal matrix composites are generally fabricated by reinforcing of different sizes(10,20,40 μm)of SiC with aluminium at a different levels(5%,10%& 15%)whereas the MoS2 addition is fixed as 2%.The effect of each control factor on response variables are analyzed through Taguchi S/N ratio method.Also,the most significant method for prediction of response parameters is satisfied by ANN model than the regression model.Analysis of variance(ANOVA)results envisage that mass fraction of SiC,feed rate is the most domineering factor on response variable.

关键词： Silicon carbide Temperature Surface roughness Cutting forces Artificial neural network Grey relational analysis