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Switchable Multicomponent Cyclization Reactions to Access Fluoroalkylated Dihydropyrimidines and Pyrimidines under Solvent-Free Conditions

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Chinese Journal of chemistry 2024年第12期42卷 1394-1398页

作者： Wanqing Zuo Zhizhen Zhu Yu Cheng Lingling Zuo Xiao Geng Zhifang Li Lei Wang College of Material chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistry and Material TechnologyMinistryof EducationHangzhouNormal UniversityHangzhouZhejiang311121China Advanced Research institute and School of Pharmaceutical Sciences Taizhou UniversityJiaojiangZhejiang 318000China state Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Comprehensive Summary The development of switchable solvent-free multicomponent reactions to build high-value-added products is an important demand for organic ***,we detailed the successful implementation of a switchable strategy for the construction of diverse 4-fluoroalkyl-1,4-dihydropyrimidines and 4-fluoroalkyl-pyrimidines via a solvent/additive-free[3+2+1]annulation,starting from readily available enamines,trifluoroacetaldehyde hydrate or 1-ethoxy-2,2-difluoroethanol and amidines *** reaction conforms to the concept of green synthesis,and provides a new avenue to access valuable fluorinated heterocycles.

关键词： Fluorine chemistry Multicomponent reactions Environmental chemistry Heterocycles Enaminones Amidines

Phase-transfer-shuttle generated in situ enables novel S1-type fluorination of sulfonium ylide with hydrofluoric acid

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Science China chemistry 2024年

作者： Yisa Xiao Rui Wang Zhaoxuan Xu Qunchao Zhao Renyi Pang Tao Dong Long Lu Qilong Shen Key Laboratory of Fluorine and Nitrogen chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy Sciences Chinese Academy of Sciences

The development of a nucleophilic fluorination protocol using hydrofluoric acid as the fluoride source represents a long-sought goal in the field of organofluorine chemistry. We report herein the realization of such a reaction that employed alkyl-substituted sulfonium ylides as the substrates. The key to the success of the protocol was attributed to two factors: First, as a Br?nsted base,the ylide was able to be protonated by HFaq, thus serving as a phase-transfer shuttle generated in situ to bring F-from aqueous phase to the organic phase promoting desolvation of fluoride ion. Second, after protonation, a sulfonium salt, a good leaving group, was generated and subsequent attacked by the fluoride to afford the alkyl fluoride. Mechanistic investigation indicates that the reaction occurs via an SN1 pathway. Because of the nature of the cationic intermediate in the reaction, two attractive rearrangement-fluorination approaches including 1,2-aryl migration fluorination and ring-expansion fluorination were disclosed.

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Palladium(Ⅱ)-Catalyzed Markovnikov Hydroalkynylation of Unactivated Terminal Alkenes

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Chinese Journal of chemistry 2024年第1期42卷 29-34页

作者： Chuanqi Hou Pinhong Chen Guosheng Liu Sstate Key Laboratory of Organometallic chemistry and Shanghai Hongkong Joint Laboratory in Chemical SynthesisCenter for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China Chang-Kung Chuang institute East China Normal UniversityShanghai 200062China

Alkynes are versatile synthons in organic synthesis,as well as important structural moieties in bioactive ***,transition metal-catalyzed hydroalkynylation of alkenes has been developed with reactive alkenes and alkenes bearing directing ***,the regioselective hydroalkynylation of simple alkenes is still ***,we have developed a palladium-catalyzed Markovnikov hydroalkynylation of unactivated terminal alkenes,which provides an efficient approach for the synthesis of branched alkynyl compounds under mild *** reaction features excellent functional group tolerance,good reaction yields and excellent ***,the asymmetric hydroalkynylation reaction has also been achieved with moderate enantioselectivity by introducing a sterically bulky chiral Pyox ligand.

关键词： Palladium catalysis Alkynylpalladation Unactivated terminal alkenes Markovnikov hydroalkynylation

Effect of Hyperconjugation on Photovoltaic Performance in Pseduo-2D Perylene Diimide Derivatives

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Chinese Journal of chemistry 2024年第7期42卷 725-730页

作者： Zhilong He Yuwen Hong Guangyu Li Tong Shan Yi Zhang Hongliang Zhong Schoolof chemistry and Chemical Engineering Shanghai Key Lab of Electrical Insulation and Thermal AgingShanghai Jiao Tong UniversityShanghai200230China Shanghai institute of organic chemistry Chinese Academy of SciencesShanghai 200032China Shenzhen Research institute Shanghai Jiao Tong UniversityShenzhenGuangdong 518057China

Theπ-πinteraction is acknowledged as the predominant factor to determine the molecular packing in organic photovoltaic materials,while other non-covalent intermolecular interactions especially theσ-πhyperconjugation are often ***,a perylene diimide(PDI)derivative named FIDT-PDI is designed and synthesized to shed light into the effect of hyperconjugation on the molecular packing and further the photovoltaic *** NMR and 2D NOE NMR demonstrate the formation of intermolecularσ-πhyperconjugation between the C—H bond of the PDI moiety in one molecule and the phenyl sidechain in another molecule of *** from theσ-πhyperconjugation,FIDT-PDI with twisted backbone reversely exhibits more ordered packing and stronger crystallinity compared with another PDI derivative FIDTT-PDI which has better planarity,consequently achieving superior PCE and higher carrier *** contribution is the first paradigm to unravel the structure-property relationship betweenσ-πhyper-conjugation of conjugated materials and corresponding photovoltaic performance.

关键词： Hyperconjugation Weak intermolecular interactions Conformation organic solar cells Nonfullerene acceptor Perylene diimide

Removal of Microcystin-LR in lake water sample by hydrophilic mesoporous silica composites under high-throughput MALDI-TOF MS detection platform

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Chinese Chemical Letters 2024年第5期35卷 380-385页

作者： Wantong Zhang Zixing Xu Guofei Dai Zhijian Li Chunhui Deng Department of chemistry Institute of Metabolism&Integrate Biology(IMIB)Fudan UniversityShanghai 200433China Jiangxi Key Laboratory of organic chemistry Jiangxi Science and Technology Normal UniversityNanchang 330013China Jiangxi Academy of Water Science and Engineering Nanchang 330029China

Microcystins(MCs),a family of cyclic heptapeptide cyanotoxins,exists in aquatic environment where cyanobacterial bloom happens,which will accumulate in aquatic organisms and transfer through the food chain to higher trophic levels,posing a health risk to both animals and human *** various MCs,Microcystin-LR(MC-LR)is worthiest studied for its strong toxicity,ubiquity and *** in this work,iminodiacetic acid(IDA)decorated magnetic mesoporous silica(mSiO_(2))nanocomposites(Fe_(3)O_(4)@mSiO_(2)-IDA)were facilely synthesized which possessed the merits of large surface area(188.21 m^(2)/g),accessible porosity(2.66 nm),excellent hydrophilicity and rapid responsiveness to magnetic *** the composites were successfully employed to the removal process of Microcystin-LR in real water samples followed by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS)analysis,achieving the removal efficiency above 92.5%even after ten recycles of the *** provided a potential method for removing MC-LR in aqueous environment with high effectiveness,lower costs and less secondary contamination.

关键词： Microcystin-LR Mesoporous silica Magnetic composites MALDI-TOF MS analysis

Synergistic asymmetric diarylation of tethered alkenes via C–H functionalization of simple(hetero)arenes

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Science China chemistry 2024年第8期67卷 2710-2718页

作者： Jian Yao Can Zhao Lili Shao Xiaohong Huo Xiaoming Wang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

By virtue of the atom-and step-economy, utilization of simple arenes as a supplant of pre-prepared aryl metal species or aryl halides for the synthesis of arylated chiral molecules has attracted great attention from the synthetic community. While transition-metal-catalyzed enantioselective diarylation of tethered alkenes has been employed to prepare important chiral cyclic compounds, the direct use of simple arenes as aryl precursors is still underdeveloped, probably due to the difficulties in the effective control of the reactivity, site-selectivity and/or enantioselectivity. Herein we report an asymmetric Pd/Ag dual metal catalytic system for the non-directed, site-and enantioselective domino Heck/intermolecular C–H functionalization of *** studies showed that Pd and Ag act in cooperation in the catalysis and the chiral bisphosphine ligand plays a bifunctional role, i.e., assisting the silver species in the cleavage of the aryl C–H bond, while inducing the enantioselectivity on direct complexation with palladium. This method provides an efficient approach to the corresponding chiral oxindoles with good enantiomeric excesses from a broad scope of arenes, including fluoroarenes, heteroarenes and several complex products derived from medicines or natural products.

关键词： asymmetric Pd/Ag dual metal catalytic system simple arenes C–H functionalization bifunctional role chiral oxindoles

Unusual Single Electron Transfer Reactions between Alkenes and Iodine Electrophiles

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Chinese Journal of chemistry 2024年第5期42卷 471-477页

作者： Zhengzhao Lou Jingyu Hu Chuanfa Ni Xiu Wang Jinbo Hu Key Laboratory of Organofluorine chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Ling Ling RoadShanghai200032 China School of Physical Science and Technology ShanghaiTech University100 Haike RoadShanghai201210 China

The electrophilic addition to an alkene with an electrophile has been widely studied and applied in organic *** organic chemistry textbook describes the classical reaction between an alkene and an iodine electrophile(such as elemental iodine and N-iodosuccinimide(NIS))as a typical ionic reaction,in which an iodonium ion is formed and then attacked by a ***,in this article,we report a new and unusual reaction mode between an alkene and NIS;that is,a single electron transfer(SET)process occurs between these two reactants by forming an electron-donor acceptor *** only does this unusual single electron transfer reaction between an alkene and NIS add fundamentally important knowledge to organic chemistry,it also provides a valuable synthetic method as the new SET reaction mode with opposite regioselectivity as compared with the traditional ionic mode.

关键词： Electrophilic addition Radical ions Reaction mechanisms Alkenes Fluorine

Synthesis and Modulation of Low-Dimensional Transition Metal Chalcogenide Materials via Atomic Substitution

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Nano-Micro Letters 2024年第9期16卷 49-94页

作者： Xuan Wang Akang Chen XinLei Wu Jiatao Zhang Jichen Dong Leining Zhang Key Laboratory of Cluster Science Ministry of Education of ChinaBeijing Key Laboratory of Photoelectronic and Electrophonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081People’s Republic of China Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of Chemistry Chinese Academy of SciencesBeijing 100190People’s Republic of China

In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk *** controllable synthesis and manipulation of these materials are crucial for tailoring their properties and unlocking their full potential in various *** this context,the atomic substitution method has emerged as a favorable *** involves the replacement of specific atoms within TMC structures with other elements and possesses the capability to regulate the compositions finely,crystal structures,and inherent properties of the resulting *** this review,we present a comprehensive overview on various strategies of atomic substitution employed in the synthesis of zero-dimensional,one-dimensional and two-dimensional TMC *** effects of substituting elements,substitution ratios,and substitution positions on the structures and morphologies of resulting material are *** enhanced electrocatalytic performance and photovoltaic properties of the obtained materials are also provided,emphasizing the role of atomic substitution in achieving these ***,challenges and future prospects in the field of atomic substitution for fabricating low-dimensional TMC materials are summarized.

关键词： Transition metal chalcogenides Atomic substitution Ion exchange Low-dimensional materials Controllable synthesis

Catalytic C-H activation-initiated transdiannulation:An oxygen transfer route to ring-fluorinated tricyclic γ-lactones

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Chinese Chemical Letters 2024年第9期35卷 145-149页

作者： Qiuyun Li Yannan Zhu Yining Wang Gang Qi Wen-Juan Hao Kelu Yan Bo Jiang School of chemistry and Chemical Engineering Yancheng Institute of TechnologyYancheng 224051China School of chemistry&Materials Science Jiangsu Normal UniversityXuzhou 221116China Key Laboratory of Life-organic Analysis of Shandong Province School of Chemistry and Chemical EngineeringQufu Normal UniversityQufu 273165China

Catalytic C–H activation-initiated annulation reactions have emerged as a versatile strategy for the efficient construction of diverse ring structural units and complex cyclic molecules in synthetic ***,we describe a new Rh(Ⅲ)-catalyzed C–H activation-initiated transdiannulation reaction of N,Ndimethyl enaminones with gem-difluorocyclopropenes in the presence of H_(2)O,enabling a facile and oxygen transfer access to ring-fluorinated tricyclicγ-lactones with a 6-5 ring-junction tetrasubstituted *** approach features bond-forming/annulation efficiency,good functional group tolerance and complete regioselectivity,which may include a complex process consisting of Rh(Ⅲ)-catalyzed C(sp2)–H activation,cyclic alkene insertion,defluorinated ring-opening of gem-difluorocyclopropane,intramolecular oxygen transfer,intramolecular cyclization and oxidative hydration.

关键词： C-H bond activation Enaminones Transannulation Oxygen transfer Regioselectivity